|Version 5 (modified by simonmar, 3 years ago)|
The Garbage Collector
GC algorithms supported:
- Copying GC
- Parallel GC?
- Marking? (for compaction or sweeping)
- Sweeping? (for mark-region GC)
The GC is designed to be flexible, supporting lots of ways to tune its behaviour. Here's an overview of the techniques we use:
- Generational GC, with a runtime-selectable number of generations (+RTS -G<n> -RTS, where n >= 1). Currently it is a traditional generational collector where each collection collects a particular generation and all younger generations. Generalizing this such that any subset of generations can be collected is a possible future extension.
- The heap grows on demand. This is straightforwardly implemented by basing the whole storage manager on a block allocator.
- Aging: objects can be aged within a generation, to avoid premature promotion. See Commentary/Rts/Storage/GC/Aging.
- The heap collection policy is runtime-tunable. You select how large a generation gets before it is collected using the +RTS -F<n> -RTS option, where <n> is a factor of the generation's size the last time it was collected. The default value is 2, that is a generation is allowed to double in size before being collected.
GC data structures
The main data structure is generation, which contains:
- a pointer to a list of blocks
- a pointer to a list of blocks containing large objects
- a list of threads in this generation
- the "remembered set", a list of blocks containing pointers to objects in this generation that point to objects in younger generations
and various other administrative fields (see includes/rts/storage/GC.h for the details).
Generations are kept in the array generations, indexed by the generation number.
A nursery is a list of blocks into which the mutator allocates new (small) objects. For resaons of locality, we want to re-use the list of blocks for the nursery after each GC, so we keep the nursery blocks rather than freeing and re-allocating a new nursery after GC.
The struct nursery contains only two fields
- the list of blocks in this nursery
- the number of blocks in the above list
In the threaded RTS, there is one nursery per Capability, as each Capability allocates independently into its own allocation area. Nurseries are therefore stored in an array nurseries, indexed by Capability number.
The blocks of the nursery notionally logically to generation 0, although they are not kept on the list generations.blocks. The reason is that we want to keep the actual nursery blocks separate from any blocks containing live data in generation 0. Generation 0 may contain live data for two reasons:
- objects live in the nursery are not promoted to generation 1 immediately, instead they are aged, first being copied to generation 0, and then being promoted to generation 1 in the next GC cycle if they are still alive.
- If there is only one generation (generation 0), then live objects in generation 0 are retained in generation 0 after a GC.


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Vulvovaginitis, vulvitis, and vaginitis are general terms that refer to the inflammation of the vagina and/or vulva (the external genital organs of a woman).These conditions can be caused by bacterial, fungal, or parasitic infections. Also, vulvovaginitis can be caused by low estrogen levels (called "atrophic vaginitis") or any type of allergic or irritation response from things such as spermicidal products, condoms, soaps, and bubble bath.
In general, vulvovaginitis causes vaginal discharge, irritation, and itching. One of the most common reasons why women visit their doctor is because of a change in vaginal discharge. It is completely normal for a woman to have a vaginal discharge, the amount and consistency of which varies during the course of the menstrual cycle. Each of the three most common types of vulvovaginitis will be described separately.
Bacterial vaginosis is the most common cause of vaginitis during the childbearing years. Forty percent to 50% of vaginitis cases are caused by bacterial vaginosis. The occurrence of bacterial vaginosis is difficult to determine but studies have proposed that 10% to 41% of
Bacterial vaginosis is not caused by a particular organism but is a change in the balance of normal vaginal bacteria. Ninety percent of the bacteria found in a healthy vagina belong to the Lactobacillus family. For unknown reasons, there is a shift in the bacterial population that results in overgrowth of other bacteria. Patients suffering from bacterial vaginosis have very high numbers of bacteria such as Gardnerella vaginalis, Mycoplasmahominis, Bacteroides species, and Mobiluncus species. These bacteria can be found at numbers 100 to 1000 times greater than found in the healthy vagina. In contrast, Lactobacillus bacteria are in very low numbers or completely absent from the vagina of women with bacterial vaginosis.
Author Info: Belinda Rowland PhD, The Gale Group Inc., Gale, Detroit, Gale Encyclopedia of Medicine, 2002This feature is for informational purposes only and should not be used to replace the care and information received from your healthcare provider. Please consult a healthcare professional with any health concerns you may have.
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Steel is one of the world’s most important engineering and construction materials, and increasingly a material of choice in commercial and residential applications.
Although no one is certain when it was first used, a British inventor named Henry Bessemer is credited with creating the first technique by which steel
could be mass-produced. Today, the metal is produced by adding a small amount of carbon to iron ore, and removing impurities, such as sulfur and phosphorous. Small amounts of alloying metals, such as nickel, manganese, chromium and vanadium may also be added.
Facts About Steel
- There are currently more than 3,500 different grades, most of which have been developed within the last few decades. The Eiffel Tower, if it were built using modern varieties of steel, would require only one-third as much steel as was used in 1889 when it was constructed.
- The recent economic boom in China and India has caused a massive increase in it’s demand.
- China is the world’s top producer, followed by Japan, Russia, and the United States, respectively.
The physical properties of steel offer significant advantages over concrete, wood, and other building materials. Here are some of these advantages:
- It is highly recyclable. In the United States, more steel is recycled than plastic, glass and aluminum combined, making it the most recycled material nationally. The reason for this is threefold: first, by virtue of its magnetic properties, steel can be easily separated from the waste stream. Second, recycling saves the steel industry an enormous amount of energy — enough to power 18 million homes for one year, according to the Steel Recycling Institute. Third, recycled steel loses none of its properties, making the recycling process simple and efficient.
- It’s use saves trees. A typical 2,000-square-foot house, which requires 26,700 board feet to build, would require the use of 102 trees, according to the the Idaho Forest Products Commission.
- More windows can be integrated in structures of steel construction, due to elevated mechanical properties of the metal. Windows reduce energy consumption and increase the comfort of building occupants.
- Steel has the highest strength-to-weight ratio of any comparable construction material, making it among the most durable.
- Steel conforms to any aesthetic. The availability of finishes, facades and other wall claddings allows builders to craft steel structures in any fashion.
- There is an unlimited production capacity. Steel’s main ingredient – iron – is one of the most common metals in the earth’s crust. The United States’ structural steel industry has the capacity to produce 6 million tons of structural steel per year, which is comfortably more than what will be needed in the foreseeable future.
- Steel is economical due to its enhanced quality and reduced costs owing to off-site fabrication and rapid construction.
- Steel is non-combustible, which allows for lower insurance costs.
Steel in Residential Construction
Steel has long been a staple in commercial construction, but the material has seen recent use in residences, as well. Increasing lumber prices and a need to conserve timber products, as well as design elements such as resistance to termites, are fueling the transition to steel in the residential construction market. In addition, steel offers excellent earthquake, fire- and wind-resistance. Steel ceiling joists can span greater distances than wooden ones, allowing for a broader range of design possibilities for builders and architects. A disadvantage, however, is that steel readily conducts heat and cold, which may degrade a home’s energy efficiency. Contractors can mitigate this potential by wrapping steel framing in insulation board, as well as by placing insulation batts between the studs. Also, noise due to thermal expansion and contraction, as well as that produced by heavy rain, may cause irritation for occupants. Steel is often used in houses in the following applications:
- rebar within concrete foundations;
- floor joists, floor bearers and columns used to raise houses off the ground;
- wall framing; and
- battens, trusses and roof sheeting.
FYI, steel is an excellent building material for residences as well as commercial buildings.
If you are really interested in building with steel, framing with steel has obvious advantages over wood. Yet building with steel requires skills that can present challenges to the wood-frame builder or framer.
The following book explains the secrets of steel framing techniques for building homes — whether pre-engineered or built by stick framing. It shows, in step-by-step instructions how to build with steel. It shows you the techniques, tools and materials — even how to estimate steel-framing costs.
You’ll find instructions for designing for steel, tools and fasteners you’ll need, foundations and anchoring, installing floor joists, standing walls, rafters and rood trusses, specialty framing, stick framing and panelization, thermal considerations, nonbearing walls, attaching exterior finished, working with subcontractors, what to expect during inspections and more.
Includes access to a FREE download with manhours, material, and labor prices, and an estimating program for estimating steel framing costs, along with steel framing details.


You just heard you have a math test on Friday — the same day as your big history test and weekly quiz on Spanish verbs. Are they crazy? How will you get all your studying done?
Don't panic. There are some secrets to good studying. These 5 study tips can help you take tests with confidence.
1. Start Studying in School
Studying for tests and quizzes actually starts way before you even know you'll have a test. Good study techniques begin in the classroom as you take notes. Note-taking is a way of remembering what you were taught or what you've read about.
Some keys to note-taking are to write down facts that a teacher mentions or writes on the board during class. If you miss something, ask your teacher to go over the facts with you after class.
Keep your notes organized by subject and making sure they're easy to read and review. This may mean that you need to recopy some notes at home or during a free period while the class is still fresh in your mind.
Unfortunately, most schools don't have classes that teach you how to take notes. When it comes to taking good notes, it can take some experimenting to figure out what works, so don't give up.
When you sit down to study, think about how much time you want to devote to each topic. This will keep you from getting overwhelmed.
If it's Monday, and you've got three tests on Friday, figure out how much time you need for studying between now and then. Then figure out how long each subject will take. For example, a weekly Spanish verb test probably won't be as intense as a big history test. So you won't need to set aside as much study time for the Spanish test — and if you break it up into a short amount every night, that's even better.
Another study technique is called "chunking" — breaking large topics down into chunks. Let's say you have a history test on World War II. Instead of thinking about studying all of World War II (which could overwhelm even an expert), try breaking your study sessions into 2-year chunks or studying the material by specific battles.
Most people can concentrate well for about 45 minutes. After that you'll probably want to take a short break. If you find yourself getting distracted and thinking about other things as you study, pull your attention back. Remind yourself that when your 45 minutes of studying are up, you can take a 15-minute break.
Many teachers tell students ahead of time what the format of an exam will be. This can help you tailor how you study. For example, if you know you're going to have multiple-choice questions on World War II, you'll know to focus on studying facts and details. But if the exam will contain essay questions, you'll want to think about which topics are most likely to be covered. Then come up with several possible essay topics and use your notes, books, and other reference sources to figure out how you might answer questions on those topics.
As you study, review your notes and any special information from your textbook. Read things over several times if you need to, and write down any phrases or thoughts that will help you remember main ideas or concepts.
When trying to memorize dates, names, or other factual information, keep in mind that it usually takes a number of tries to remember something correctly. That's one reason why it's a good idea to start studying well in advance of a test. Use special memory triggers that the teacher may have suggested or ones that you invent yourself.
In the case of math or science problems or equations, do some practice problems. Pay special attention to anything the teacher seemed to stress in class. (This is where good note-taking comes in handy!)
Some people find it helps to teach what they're studying aloud to an imaginary student. Or work with a study partner and take turns teaching aloud. Another study technique is making flashcards that summarize some of the important facts or concepts. You can then use these to review for a test.
It's tempting to put off studying until the last minute (also known as procrastination). Unfortunately, by the time students get to high school there's so much going on that there's usually no room for procrastination.
If you're a procrastinator (and who isn't sometimes?), one of the best ways to overcome it is by staying organized. After you've written test dates and project due dates on a calendar, it's hard to ignore them. And sitting down to organize and plan your work really highlights how much time things take. Organization makes it harder to procrastinate.
Sometimes people put off studying because they feel overwhelmed by the fact that they're behind on things or they just feel really disorganized. Don't let this happen to you. Keep your notes organized, stay on top of required readings, and follow the other study tips mentioned earlier to stay focused and in control. Your teachers will give you plenty of notice on important tests so you have enough time to study for the type of exam you'll be taking.
But what if you're feeling overwhelmed by all the stuff you have to do? Are classes or extracurricular activities limiting your time to study properly? Ask your teachers for help prioritizing. You may need to involve the people in charge of your activities — such as your coach or music or drama teacher — in working out a solution.
Don't wait until the last minute to talk to your teachers, though, or you'll just look like a procrastinator! And don't be afraid to ask for help. Teachers respect students who are thoughtful and interested in learning and doing well.
Sometimes it can be useful to go over things with people who are studying for the same test: You can make sure that your notes are correct and that you understand the subject. Study groups are also helpful because you can work together to come up with ways to remember concepts and then test one another.
For some people who are easily distracted, though, study groups spell disaster because they get off the topic. When you're with a bunch of friends or classmates, you may spend more time hanging out than actually studying. One way to ensure quiet and focus when studying with a group is to study in the library. You'll be forced to keep things more low-key than if you're at someone's kitchen table.
In the end, it comes down to what works best for you. If you like to study alone and feel most confident doing it that way, that's great. If you think you'd like to work in a group, try it out — just be aware of the drawbacks.
When you've finished studying, you should feel like you can approach the test or quiz with confidence — not necessarily that you will get 100% of the answers correct, but that you have a good understanding of the information.
Most of all, don't panic if you can't remember some facts the night before the test. Even if you've spent all evening studying, the brain needs time to digest all that information. You'll be surprised by what comes back to you after sleeping.


Inductively Coupled Plasma-Mass Spectrometry
Inductively Coupled Plasma-Mass Spectrometry (ICP) is a powerful technique of chemical characterization capable of simultaneously measuring up to 50 different trace elements, sometimes at concentrations as low as several parts per billion. The ICP-MS functions by passing small amounts of material into a plasma, a super-heated gas, which ionizes the sample material. The plasma itself operates at around 8000 degrees C, a temperature greater than the surface of the sun. This ionized sample is then sent through a series of powerful magnets called a mass spectrometer, which separates sample ions on the basis of their mass/charge ratio. These ions are then measured by a detector to establish sample composition.
Sample can be introduced into the ICP-MS either as a vaporized solid, or as a liquid. One such method is Laser Ablation, in which a pulsed laser is used to remove small amounts of sample material, which is then swept into the plasma via a Helium carrier gas. Alternatively, samples can be dissolved in solution and sent into the plasma in liquid form. Depending on sample composition, this may involve dissolving the sample in strong acids, assited by high heat and pressure produced by bombarding the sample with microwaves. Our Inductively Coupled Plasma Mass Spectrometry (ICP-MS) Laboratory operates around a high sensitivity Varian quadrupole ICP-MS and a New Wave UP213 laser ablation system for solid sample introduction. Additionally, the ICP-MS laboratory houses a Milestone microwave digestion system for sample dissolution and liquid sample introduction.
The EAF ICP-MS laboratory. The Varian ICP-MS is connected to our adaptable chamber UP266 laser ablation system, with a ceramic vessel from the north coast of Papua New Guinea positioned for analysis.
Laser Ablation is particularly valuable due to its ability to target specific components of samples. For ceramics, it is possible to target paste, paints, temper, slips, and glazes separately. In one study performed by museum scientists, the glazes on Chinese Blue and White porcelains and Celadon wares were analyzed chemically by LA-ICP-MS. This study demonstrated that the majority of such ceramics found at archaeological sites in western India and eastern Africa were produced by Chinese kilns, and were not imitation wares produced at Middle Eastern or southeast Asian kilns. Other projects have studied production and exchange of ceramics from Belgian Neolithic sites, proto-historical and historical archaeological sites in the Phillippines, Chinese Neolithic sites, ceramics on the northern coast of Papua New Guinea, and archaeological ceramics from throughout the central Andes. Likewise, LA-ICP-MS can be used to analyze metal and corrosion products separately on metal artifacts, eliminating problems that have plagued bulk characterization studies of archaeological metals. LA-ICP-MS is also highly useful for rapidly characterzing obsidian and artificial glasses. The EAF has large ongoing projects applying LA-ICP-MS to characterize glass beads traded in the Indian Ocean, and obsidian from archaeological sites in the western Pacific, Andes, and Belize.
The EAF also houses a modified adaptable chamber New Wave UP266 laser ablation system developed in collaboration with Dr. Richard Cox at the University of Quebec at Chicoutimi, Canada. This adaptable chamber laser ablation system is the first of its kind applied in a museum setting, having only been employed in experimental industrial systems previously. As such, it equips the Field Museum with unique, virtually non-destructive, high precision, multi-element analysis for large objects that cannot be destructively subsampled, such as complete ceramic vessels. Ongoing projects using the adaptable chamber to analyze collections objects include analysis of glass objects from the Sumerian city of Kish, and analysis of ceramics from the western Pacific.


UCIL identified two Uranium blocks named Killung and Rangam in West Khasi hills district of Meghalaya, with total reserves of 9.22 million tones with rated capacity of 0.375 MTPA. The project has acquired 351 ha of land for the establishment of mines, processing plant, DCDA plant (for H2SO4 plant), township and other facilities.
Both mining blocks will produce 9.22 million tones of Uranium ore and 62 million tones of waste materials (overburden) in 24 years. The Killung block is divided into Killung A and Killung B and Rangam block will mine separately as a single block. The executive summary is silent on whether all blocks will be operated simultaneously or will operate in stages. However, it seems that both blocks will be mined simultaneously because there are wide various in uranium percentage in the ores of Killung A and Killung B and Rangam.
Location wise project is very sensitive because project is located in hilly terrain and receives very high rainfall. Further, project site is an important watershed of various tributaries and rivers. Therefore, estimation of silt load and erosion potential of an area is crucial, however the executive summary has failed to address this significant issue.
Executive summary is silent on quantity and quality of tailing wastes, the report states that tailing waste will be stored initially in tailing pond adjacent to plant and disposed off in mined out area along with overburden. This will commenced from the fifth year. According to the executive summary, processing plant and tailing ponds are located in the watershed of Mawkhan River, which is a tributary of Wah Phodthra River. Hence a potential risk of surface water contamination is high. Moreover, executive summary is competently silent on the impacts of project on the watershed and also failed to highlight the safeguard strategies. The executive summary is also silent on quality, quantity and mode of disposal of wastewater from the process plant.
Executive summary has failed to provide information on the land use pattern of acquired land and landuse pattern in buffer zone such as forest cover, agricultural land, wasteland etc.
The proposed uranium ore handling and its management seem very poor. The crusher will crush ore at the mine pit; crushed ore will be transported continuously to the processing plant by the dumper after covering a distance of 5.5 km. Further, the crushed ore is proposed to store in open at the processing plant. Hence, high radiation risk could be anticipated through air borne particles. Further, multiple handling of ore, coupled with dumper transportation and open storage would likely to increase the risk of air and water contamination.
The background level of gamma radiation at the proposed site is comparatively higher with respect to global average 0.9mSv.y-1. According to the executive summary, the radon level around the proposed site was 60 to 91 Bqm-3 and in the village area it ranges from 6.7 to 23.8 Bqm-3, which is comparatively less with respect to prescribed range (workplace range 600 to 1500 Bqm-3, dwelling range 200 to 600 Bqm-3) given by ICRP. The hilly terrain coupled with high rainfall clearly indicates that entire area is highly vulnerable to pollution. It can be anticipated that both silt and radioactive substances would contaminate the exiting rivers in the area once the mines and plant begins to operate at full rated capacity. It could be anticipated that background concentration of radioactive substances would likely to increase in future because of site sensitivity and poor proposed solid waste management (mine i.e. overburden, ore processing plant i.e. tailing waste). The natural river would be worst impacted by overburden and tailing pond because tailing pond and ore processing plant is proposed in the watershed of the river.
The executive summary states that the background concentration of uranium in surface water is low but failed to provide the background concentration level. The report has referred AMD data on the background concentration, which was conducted during 1990 –1998. As per AMD data, background level of Uranium was in the range of< 0.1 to 1.1 mg. m-3 and radium-226 in the range 15 to 115 Bqm-3.
The executive summary is silent on flora and fauna status in the study area and failed to provide information on biodiversity such as presence of scheduled listed species, forest cover area and forest density. According to forest department, fauna in West Khasi district is characterize by the presence of elephants, apes, monkeys, deer, sambar, tigers, wild boars, bears, leopards. It clearly shows that schedule I listed animals exist in the region but executive summary failed to provide any information on flora and fauna characteristic in the study areas.
Executive summary is silent on the overburden management; the report states that around 39 ha of land are earmarked for the initial dumping of overburden materials. It seems that at the initial stage of mining, external dumping will be undertaken. If this is the scenario, then high siltation risk, increase of radioactive contaminants in the surface water could be anticipated. The risk probability would be of high magnitude because mine lease areas provides water to Umshopphnew and Wahphodthra rivers, both these rivers finally drains in Kynshi River. The report also states that mine will generate 2.5 million tones of overburden per year but failed to provide basic information like commencement of backfilling and mine reclamation.
The plant will also generate large quantity of solid waste from the process, DCDA plant, ETP plant. But no information is available on the characteristic, quantity and mode of solid wastes disposal.


Large circular ear ornaments were popular personal adornments of prominent ancient Peruvian lords and a symbol of their status and wealth. The weight of the frontal, which could reach widths of more than four inches, was counterbalanced by a long tubular shaft that went through the distended hole in the earlobe. Particularly impressive are those earflares with colorful mosaics. On this pair, bird-headed (or masked) winged runners, worked in turquoise, sodalite, and spondylus shell, hold bags in their outstretched hands. Their eyes and beaks are sheathed in gold. They may be depictions of mythological messengers.


Cure for eczema comes closer to realityPublished On: Thu, Nov 24th, 2011 | Skin care | By BioNews
An effective cure for inflammatory skin conditions like eczema is a step closer to reality, researchers say.
Scientists have found that a strain of yeast implicated in skin conditions like eczema, can be killed by certain peptides and could provide a new treatment for these debilitating skin conditions.
20 percent of children in the UK suffer from atopic eczema and whilst this usually clears up in adolescence, 7 percent of adults will continue to suffer throughout their lifetime.
Furthermore, this type of eczema, characterized by dry, itchy, flaking skin, is increasing in prevalence. Whilst the cause of eczema remains unknown, one known trigger factor is the yeast Malassezia sympodialis.
This strain of yeast is one of the most common skin yeasts in both healthy individuals and those suffering from eczema. The skin barrier is more fragile and often broken in those suffering from such skin conditions, and this allows the yeast to cause infection, which then further exacerbates the condition.
Scientists at Karolinska Institute in Sweden looked for a way to kill Malassezia sympodialis without harming healthy human cells.
The researchers looked at the effect on the yeast of 21 peptides that had either; cell-penetrating or antimicrobial properties.
Cell-penetrating peptides are often investigated as drug delivery vectors and are able to cross the cell membrane, although the exact mechanism for this is unknown.
Antimicrobial peptides, on the other hand, are natural antibiotics and kill many different types of microbe including some bacteria, fungi and viruses.
Tina Holm and her colleagues added these different peptides types to separate yeast colonies and assessed the toxicity of each peptide type to the yeast.
They found that six of the 21 peptides they tested, successfully killed the yeast without damaging the membrane of keratinocytes, human skin cells.
“Many questions remain to be solved before these peptides can be used in humans,” Holm said.
“However, the appealing combination of being toxic to the yeast at low concentrations whilst sparing human cells makes them very promising as antifungal agents.”
“We hope that these peptides in the future can be used to ease the symptoms of patients suffering from atopic eczema and significantly increase their quality of life,” she added.
The study was recently published in the Society for Applied Microbiology’s journal, Letters in Applied Microbiology.


The samurai dominated Japanese society for 700 years, and the vision of this class permeates Japanese culture. Ever present is the samurai's sword — as a tool, a companion, and a symbol.
The samurai sword is both a technical marvel and a significant cultural object. As a technology, it involves a large system of craftsmen, distinct stages of and for the materials, and a long apprenticeship to develop the necessary skills. Culturally, the sword is surrounded by a history of legend, prescribed behaviors, and complex status relationships. Like a many-faceted diamond, a close examination of this one tool can give us a wide perspective on Japanese culture.
To study the relationship between the samurai and his sword, we will study the whole of samurai history. The role the sword has played has changed over time, but so have the times brought out different aspects of that many-layered relationship. The sword makes the samurai, makes him its wielder as much as he makes it his weapon.
How was the technology of the sword appropriate to the samurai, and what roles did it play? We will spend considerable time exploring the psyche of the samurai, particularly with respect to Zen anti-ideology. How is Zen reflected in the samurai and in his sword? We will also follow Japanese history as it revolves around samurai. By what fire is the samurai's identity forged, and what of today's society can its gleaming edge cut apart?
|SES # ||TOPICS ||READINGS ||QUESTIONS |
|1 ||Introduction to Japan || |
Storry, Richard. Fig. 1-2 and "The Silent Warrior." The Way of the Samurai. London, England: Orbis Books, 1978, pp. 7-17. ISBN: 9780856134043.
Suzuki, Daisetz. "Zen and Swordsmanship I." Chapter V in Zen and Japanese Culture. Princeton, NJ: Princeton University Press, 1970, pp. 89-93. ISBN: 9780691017709.
|2 ||The katana || Kapp, Leon, Hiroko Kapp, and Yoshindo Yoshihara. "A Craft Reborn," and "The Sword." The Craft of the Japanese Sword. New York, NY: Kodansha International, 1987, pp. 17-27, 53-55 and 61-94. ISBN: 9780870117985. ||(PDF) |
|3 ||The samurai's cultural origins || |
Tsunoda, Ryusaku, William T. Bary, and Donald Keene. Sources of Japanese Tradition, Vol. I: From Earliest Times to 1600. New York, NY: Columbia University Press, 1964.
Please read one of:
- pp. 21-26
- pp. 14-17 and 27-29
- pp. 17-18, 29-30 and 274-276
Beaseley, W. G. "Buddhism and Shinto." In The Japanese Experience: A Short History of Japan. Berkeley, CA: University of California Press, 2000, pp. 42-47. ISBN: 9780520225602.
Storry, Richard. "The Samurai Emerges." The Way of the Samurai. London, England: Orbis Books, 1978, pp. 18-41. ISBN: 9780856134043.
|4 ||The code of the samurai || |
Heike Monogatari [The Tale of the Heike]. Translated by Kitagawa Hiroshi and Bruce T. Tsuchida. Tokyo, Japan: University of Tokyo Press, 1975. Chapter 1, p. 5; Chapter 9, pp. 519-523; Chapter 11, pp. 676-689. ISBN 1: 9780860081883 and ISBN 2: 9780860081890.
Tsunemoto, Tamamoto. Hagakure: The Book of the Samurai. Vol. I. Tokyo, Japan: Hokuseido Press, 1980, sections 2-5, 9 and 12, pp. 35-40. ISBN: 9780893461690.
|5 ||Zen and the samurai ||Please read one of: |
- Hoffman, Yoel. "The Haiku," "Death Poems and Zen Buddhism," and poems by Kozan Ichikyo, Suzuki Shosan, Taigen Sofu, Takuan Soho, Zoso Royo, and Bashō. Japanese Death Poems. Rutland, VT: C. E. Tuttle, 1986, pp. 22-27, 65-76, 108, 117-19, 129 and 143. ISBN: 9780804831796.
- Storry, Richard. "Zen and the Sword." The Way of the Samurai. London, England: Orbis Books, 1978, pp. 43-61. ISBN: 9780856134043.
- Suzuki, Daisetz. "What is Zen?" and "Zen and the Samurai." Chapters I, IV in Zen and Japanese Culture. Princeton, NJ: Princeton University Press, 1970, pp. 7-15 and 70-85. ISBN: 9780691017709.
|6 ||Civil war and unification || |
Yoshikawa, Eiji. Taiko. New York, NY: Kodansha International, 1992, pp. 653-663. ISBN: 9784770015709.
Please read one of:
- Beaseley, W. G. "The Unifiers." Chapter 7 in The Japanese Experience: A Short History of Japan. Berkeley, CA: University of California Press, 2000, pp. 116-127. ISBN: 9780520225602.
- Berry, Mary Elizabeth. "The Sword Hunt." and "Freezing the Social Order." Chapter 5 in Hideyoshi. Cambridge, MA: Council on East Asian Studies at Harvard University, 1989, pp. 102-111. ISBN: 9780674390263.
|7 ||Giving up the gun || Perrin, Noel. Chapters 1-4 in Giving Up the Gun: Japan's Reversion to the Sword. Boston, MA: D. R. Gordine, 1988. ISBN: 9780879237738. ||(PDF) |
|8 ||The Tokugawa state || |
Storry, Richard. "The Armed Mandarins." The Way of the Samurai. London, England: Orbis Books, 1978, pp. 63-77. ISBN: 9780856134043.
Sadler, A. L. "The Legacy of Ieyasu." In The Maker of Modern Japan: The Life of Shogun Tokugawa. Rutland, VT: C. E. Tuttle, 1978, pp. 387-398. ISBN: 9780804812979.
The lab for this module is to do blacksmithing (forging) in the MIT forge. After a demonstration, students sign up for four times to work on projects they choose themselves — from small household items to attempts at Samurai swords (the latter is discouraged, though, as it takes about six months to complete). The MIT crest features a blacksmith, because MIT is dedicated to the intricacies of practice, but few students have a chance to get so close to such a concrete engineering problem. Forging is delicate work, requiring both skill and an understanding of the chemistry of iron. We hope that after this lab, students have a greater appreciation for the "learning" necessary for, and part of, "doing."


Two hundred years ago this week, during the War of 1812, an Ohio fort was front and center as American forces battled the British for control of Lake Erie and the region around it. If the British and their allies had prevailed, places like Toledo, Sandusky, Vermilion, Lorain, Cleveland and Conneaut might be on maps of Canada today.
This weekend in Perrysburg, historic Fort Meigs observes the 200th anniversary of the bloodiest day of fighting there during the three-year War of 1812 -- May 5, 1813, the First Siege of Fort Meigs. More...
Visit the fort this Friday, May 3, through Sunday, May 5, 2013, and meet hundreds of War of 1812 re-enactors from the United States and Canada portraying those who fought there. Explore authentic 1812-era military camps and see battle re-enactments, fife and drum concerts, musket and cannon firings and more.


Statistical modeling could help us understand cosmic accelerationDecember 24th, 2010 in Physics / General Physics
(PhysOrg.com) -- While it is generally accepted by scientists that the universe is expanding at an accelerated rate, there are questions about why this should be so. For years, scientists have been trying to determine the cause of this behavior. One of the theories is that dark energy could be the cause of cosmic acceleration.
In order to test theories of dark energy, a group at Los Alamos National Laboratory in New Mexico and the University of California Santa Cruz came up with a technique designed to test different models of dark energy. We are trying to investigate what could be behind the accelerated expansion of the universe, Katrin Heitmann, one of the Los Alamos scientists tells PhysOrg.com. Our technique is based on data, and can be used to evaluate different models.
Heitmann and her collaborators created their method based on Gaussian process modeling; the implementation was led by Tracy Holsclaw from UC Santa Cruz. Were using statistical methods rather than trying to come up with different models. Our process takes data from different sources and then uses it to look for certain deviations from what we assume in a cosmological constant. The groups work can be seen in Physical Review Letters: Nonparametric Dark Energy Reconstruction from Supernova Data.
Many scientists think that dark energy is driving the accelerated expansion of the universe, Heitmann says. If this is the case, it is possible to characterize it via its equation of state w(z). The redshift evolution of the equation of state parameter w(z) would show some indication of a dynamical origin of dark energy.
Heitmann points out that in such a case, there could be an infinite number of models. We cant test all those models, she says, so we have to do an inverse problem. We have data and we can characterize the underlying cause of the accelerated expansion. It assumes that w is a smoothly varying function, and a dynamical dark energy theory would fit that. We can use data and analyze it to see if we can find indications that dark energy really is behind accelerated expansion.
The Los Alamos and University of California, Santa Cruz team first tested their statistical technique on simulated data in order see whether the method was reliable. After we saw that it was, Heitmann says, we tried it on currently available supernova data.
So far, their analysis has not revealed that a dynamical dark energy is behind the accelerated expansion (the cosmological constant is a very special case of dark energy and is still in agreement with the data), but Heitmann doesnt think that means that the door is closed on dynamical dark energy theories as the cause of acceleration in the expanding universe. The data so far is limited, and better data is coming in every day, she says. Additionally, the group hopes to include other data in their statistical analyses. Our technique allows for the input of data from cosmic microwave background and baryon acoustic oscillations as well, and thats what we want to add in next.
If this technique does identify a dynamical dark energy as the reason behind accelerated expansion of the universe, it could mean revisiting the basics of what we know about the workings of the universe. If we do find the time dependence that supports the idea of dark energy as this mechanism, then we can go back to the theory approach. We would have an idea of which models could better explain universes expansion history and ultimately develop a self-consistent theory with no ad hoc assumptions.
More information: Tracy Holsclaw, Ujjaini Alam, Bruno Sansó, Herbert Lee, Katrin Heitmann, Salman Halbib, and David Higdon, Nonparametric Dark Energy Reconstruction from Supernova Data, Physical Review Letters (2010). Available online: link.aps.org/doi/10.1103/PhysRevLett.105.241302
Copyright 2010 PhysOrg.com.
All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com.
"Statistical modeling could help us understand cosmic acceleration." December 24th, 2010. http://phys.org/news/2010-12-statistical-cosmic.html


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Giuseppe Peano's parents worked on a farm and Giuseppe was born in the farmhouse 'Tetto Galant' about 5 km from Cuneo. He attended the village school in Spinetta then he moved up to the school in Cuneo, making the 5km journey there and back on foot every day. His parents bought a house in Cuneo but his father continued to work the fields at Tetto Galant with the help of a brother and sister of Giuseppe, while his mother stayed in Cuneo with Giuseppe and his older brother.
Giuseppe's mother had a brother who was a priest and lawyer in Turin and, when he realised that Giuseppe was a very talented child, he took him to Turin in 1870 for his secondary schooling and to prepare him for university studies. Giuseppe took exams at Ginnasio Cavour in 1873 and then was a pupil at Liceo Cavour from where he graduated in 1876 and, in that year, he entered the University of Turin.
Among Peano's teachers in his first year at the University of Turin was D'Ovidio who taught him analytic geometry and algebra. In his second year he was taught calculus by Angelo Genocchi and descriptive geometry by Giuseppe Bruno. Peano continued to study pure mathematics in his third year and found that he was the only student to do so. The others had continued their studies at the Engineering School which Peano himself had originally intended to do. In his third year Francesco Faà di Bruno taught him analysis and D'Ovidio taught geometry. Among his teachers in his final year were again D'Ovidio with a further geometry course and Francesco Siacci with a mechanics course. On 29 September 1880 Peano graduated as doctor of mathematics.
Peano joined the staff at the University of Turin in 1880, being appointed as assistant to D'Ovidio. He published his first mathematical paper in 1880 and a further three papers the following year. Peano was appointed assistant to Genocchi for 1881-82 and it was in 1882 that Peano made a discovery that would be typical of his style for many years, he discovered an error in a standard definition.
Genocchi was by this time quite old and in relatively poor health and Peano took over some of his teaching. Peano was about to teach the students about the area of a curved surface when he realised that the definition in Serret's book, which was the standard text for the course, was incorrect. Peano immediately told Genocchi of his discovery to be told that Genocchi already knew. Genocchi had been informed the previous year by Schwarz who seems to have been the first to find Serret's error.
In 1884 there was published a text based on Genocchi's lectures at Turin. This book Course in Infinitesimal Calculus although based on Genocchi's lectures was edited by Peano and indeed it has much in it written by Peano himself. The book itself states on the title page that it is:-
... published with additions by Dr Giuseppe Peano.
Genocchi seemed somewhat unhappy that the work came out under his name for he wrote:-
... the volume contains important additions, some modifications, and various annotations, which are placed first. So that nothing will be attributed to me which is not mine, I must declare that I have had no part in the compilation of the aforementioned book and that everything is due to that outstanding young man Dr Giuseppe Peano ...
Peano received his qualification to be a university professor in December 1884 and he continued to teach further courses, some for Genocchi whose health had not recovered sufficiently to allow him to return to the University.
In 1886 Peano proved that if f (x, y) is continuous then the first order differential equation dy/dx = f (x, y) has a solution. The existence of solutions with stronger hypothesis on f had been given earlier by Cauchy and then Lipschitz. Four years later Peano showed that the solutions were not unique, giving as an example the differential equation dy/dx = 3y2/3 , with y(0) = 0.
In addition to his teaching at the University of Turin, Peano began lecturing at the Military Academy in Turin in 1886. The following year he discovered, and published, a method for solving systems of linear differential equations using successive approximations. However Émile Picard had independently discovered this method and had credited Schwarz with discovering the method first. In 1888 Peano published the book Geometrical Calculus which begins with a chapter on mathematical logic. This was his first work on the topic that would play a major role in his research over the next few years and it was based on the work of Schröder, Boole and Charles Peirce. A more significant feature of the book is that in it Peano sets out with great clarity the ideas of Grassmann which certainly were set out in a rather obscure way by Grassmann himself. This book contains the first definition of a vector space given with a remarkably modern notation and style and, although it was not appreciated by many at the time, this is surely a quite remarkable achievement by Peano.
In 1889 Peano published his famous axioms, called Peano axioms, which defined the natural numbers in terms of sets. These were published in a pamphlet Arithmetices principia, nova methodo exposita which, according to  were:-
... at once a landmark in the history of mathematical logic and of the foundations of mathematics.
The pamphlet was written in Latin and nobody has been able to give a good reason for this, other than :-
... it appears to be an act of sheer romanticism, perhaps the unique romantic act in his scientific career.
Genocchi died in 1889 and Peano expected to be appointed to fill his chair. He wrote to Casorati, who he believed to be part of the appointing committee, for information only to discover that there was a delay due to the difficulty of finding enough members to act on the committee. Casorati had been approached but his health was not up to the task. Before the appointment could be made Peano published another stunning result.
He invented 'space-filling' curves in 1890, these are continuous surjective mappings from [0,1] onto the unit square. Hilbert, in 1891, described similar space-filling curves. It had been thought that such curves could not exist. Cantor had shown that there is a bijection between the interval [0,1] and the unit square but, shortly after, Netto had proved that such a bijection cannot be continuous. Peano's continuous space-filling curves cannot be 1-1 of course, otherwise Netto's theorem would be contradicted. Hausdorff wrote of Peano's result in Grundzüge der Mengenlehre in 1914:-
This is one of the most remarkable facts of set theory.
In December 1890 Peano's wait to be appointed to Genocchi's chair was over when, after the usual competition, Peano was offered the post. In 1891 Peano founded Rivista di matematica, a journal devoted mainly to logic and the foundations of mathematics. The first paper in the first part is a ten page article by Peano summarising his work on mathematical logic up to that time.
Peano had a great skill in seeing that theorems were incorrect by spotting exceptions. Others were not so happy to have these errors pointed out and one such was his colleague Corrado Segre. When Corrado Segre submitted an article to Rivista di matematica Peano pointed out that some of the theorems in the article had exceptions. Segre was not prepared to just correct the theorems by adding conditions that ruled out the exceptions but defended his work saying that the moment of discovery was more important than a rigorous formulation. Of course this was so against Peano's rigorous approach to mathematics that he argued strongly:-
I believe it new in the history of mathematics that authors knowingly use in their research propositions for which exceptions are known, or for which they have no proof...
It was not only Corrado Segre who suffered from Peano's outstanding ability to spot lack of rigour. Of course it was the precision of his thinking, using the exactness of his mathematical logic, that gave Peano this clarity of thought. Peano pointed out an error in a proof by Hermann Laurent in 1892 and, in the same year, reviewed a book by Veronese ending the review with the comment:-
We could continue at length enumerating the absurdities that the author has piled up. But these errors, the lack of precision and rigour throughout the book take all value away from it.
From around 1892, Peano embarked on a new and extremely ambitious project, namely the Formulario Mathematico. He explained in the March 1892 part of Rivista di matematica his thinking:-
Of the greatest usefulness would be the publication of collections of all the theorems now known that refer to given branches of the mathematical sciences ... Such a collection, which would be long and difficult in ordinary language, is made noticeably easier by using the notation of mathematical logic ...
In many ways this grand idea marks the end of Peano's extraordinary creative work. It was a project that was greeted with enthusiasm by a few and with little interest by most. Peano began trying to convert all those around him to believe in the importance of this project and this had the effect of annoying them. However Peano and his close associates, including his assistants, Vailati, Burali-Forti, Pieri and Fano soon became deeply involved with the work.
When describing a new edition of the Formulario Mathematico in 1896 Peano writes:-
Each professor will be able to adopt this Formulario as a textbook, for it ought to contain all theorems and all methods. His teaching will be reduced to showing how to read the formulas, and to indicating to the students the theorems that he wishes to explain in his course.
When the calculus volume of the Formulario was published Peano, as he had indicated, began to use it for his teaching. This was the disaster that one would expect. Peano, who was a good teacher when he began his lecturing career, became unacceptable to both his students and his colleagues by the style of his teaching. One of his students, who was actually a great admirer of Peano, wrote:-
But we students knew that this instruction was above our heads. We understood that such a subtle analysis of concepts, such a minute criticism of the definitions used by other authors, was not adapted for beginners, and especially was not useful for engineering students. We disliked having to give time and effort to the "symbols" that in later years we might never use.
The Military Academy ended his contract to teach there in 1901 and although many of his colleagues at the university would have also liked to stop his teaching there, nothing was possible under the way that the university was set up. The professor was a law unto himself in his own subject and Peano was not prepared to listen to his colleagues when they tried to encourage him to return to his old style of teaching. The Formulario Mathematico project was completed in 1908 and one has to admire what Peano achieved but although the work contained a mine of information it was little used.
However, perhaps Peano's greatest triumph came in 1900. In that year there were two congresses held in Paris. The first was the International Congress of Philosophy which opened in Paris on 1 August. It was a triumph for Peano and Russell, who attended the Congress, wrote in his autobiography:-
The Congress was the turning point of my intellectual life, because there I met Peano. I already knew him by name and had seen some of his work, but had not taken the trouble to master his notation. In discussions at the Congress I observed that he was always more precise than anyone else, and that he invariably got the better of any argument on which he embarked. As the days went by, I decided that this must be owing to his mathematical logic. ... It became clear to me that his notation afforded an instrument of logical analysis such as I had been seeking for years ...
The day after the Philosophy Congress ended the Second International Congress of Mathematicians began. Peano remained in Paris for this Congress and listened to Hilbert's talk setting out ten of the 23 problems which appeared in his paper aimed at giving the agenda for the next century. Peano was particularly interested in the second problem which asked if the axioms of arithmetic could be proved consistent.
Even before the Formulario Mathematico project was completed Peano was putting in place the next major project of his life. In 1903 Peano expressed interest in finding a universal, or international, language and proposed an artificial language "Latino sine flexione" based on Latin but stripped of all grammar. He compiled the vocabulary by taking words from English, French, German and Latin. In fact the final edition of the Formulario Mathematico was written in Latino sine flexione which is another reason the work was so little used.
Peano's career was therefore rather strangely divided into two periods. The period up to 1900 is one where he showed great originality and a remarkable feel for topics which would be important in the development of mathematics. His achievements were outstanding and he had a modern style quite out of place in his own time. However this feel for what was important seemed to leave him and after 1900 he worked with great enthusiasm on two projects of great difficulty which were enormous undertakings but proved quite unimportant in the development of mathematics.
Of his personality Kennedy writes in :-
... I am fascinated by his gentle personality, his ability to attract lifelong disciples, his tolerance of human weakness, his perennial optimism. ... Peano may not only be classified as a 19th century mathematician and logician, but because of his originality and influence, must be judged one of the great scientists of that century.
Although Peano is a founder of mathematical logic, the German mathematical philosopher Gottlob Frege is today considered the father of mathematical logic.
Article by: J J O'Connor and E F Robertson
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How to find a missing number in a sequence
- Determine if the order of numbers is ascending (getting larger in value) or descending (becoming smaller
- Find the difference between numbers that are next to each other.
- Use the difference between numbers to find the missing number.
Example: Find the missing number: 15, 13, ?, 9
- The order of numbers is going down or descending.
- The difference between numbers is 15 - 13 = 2
- Since the order is descending subtract 2 from 13. The missing number may be 11.
- The missing number is 11 since it is 2 more than the last number 9.


Keynes at the Border?
Wednesday, April 15, 2009
A common fallacy holds that imposing taxes on imports and rebating taxes on exports would stimulate the economy.
A common fallacy holds that border tax adjustments—imposing taxes on imports and rebating taxes on exports—would enhance American exports and reduce imports. The reasoning behind this mistake is simple enough. A border adjustment seems to provide a subsidy to exporters and to levy a tariff on importers. Border adjustment proponents, noting that international trade rules allow nations to border adjust consumption taxes such as European-style value added taxes, urge the adoption of a consumption tax in the United States so that we can border adjust and enhance our trade competitiveness.
Yet, such an argument ignores an essential truth about imports and exports: over the long term, exports and imports must be equal. We can think of a country like a household. Purchases are paid for from the proceeds of sales, and sales are made for the purpose of additional purchases. In the long run, purchases and sales must be equal. A nation’s trade policy works the same way. Over a nation’s history, the value of exports in current dollars must equal the value of imports in present value. Any attempt to permanently increase exports and decrease imports is futile.
What would actually happen if we border adjusted imports and exports is that exchange rate movements would offset the trade effects and the dollar would appreciate. The key variable is the real exchange rate, which determines the terms at which a country buys and sells. (For the United States, the real exchange rate is the value of the dollar in terms of foreign currency—the nominal exchange rate—multiplied by the U.S. price level and divided by the foreign price level.) The real exchange rate adjusts to keep the present discounted value of exports and imports equal. The adoption of a border adjustment by the United States would trigger an increase in the real exchange rate that would offset the perceived boost to exports and the perceived restraint on imports.
The argument for border tax adjustments ignores an essential truth about imports and exports.
Imagine, for the moment, that one euro and one dollar have the same value under the current trade regime. If a firm in the United States wanted to import one euro’s worth of German chocolate, the cost of the chocolate to the importer would be one dollar.
Now, let’s imagine that we institute a 25 percent border adjustment. The cost of the chocolate to the importer would increase to €1.33 (25 percent of 1.33 is 0.33). At the same time, the dollar would appreciate to €1.33; conversely, one euro would be worth 75 cents. At the new exchange rate, the €1.33 chocolate would still cost the importer one dollar, so there would be no net increase in cost.
The same dynamics would be at play in the case where the United States is an exporter. Imagine that a German importer wants to buy one dollar worth of Florida oranges, which would cost one euro under the current trade regime. Under the border adjustment, the United States would rebate the American exporter 25 percent, so the cost to the German importer would decrease to 75 cents. Because the dollar would appreciate to €1.33, however, the cost to the German importer would still be one euro. There would be no competitive advantage for U.S. exports.
These examples reveal that the impact on overall trade flows would be neutral.
Even if a border adjustment could permanently increase exports and reduce imports, the impact of the change would be disastrous for an economy. In that case, the United States would send more goods and services, produced by our own labor and resources, abroad while receiving fewer goods and services in return. Because imports are the gain from trade while exports are the cost of trade, a permanent increase in net exports would reduce our standard of living. Although attractive at face value, the desire to permanently increase exports and reduce imports reflects the misguided view known as mercantilism, the doctrine that Adam Smith condemned so forcefully in 1776.
Even if a border adjustment could permanently increase exports and reduce imports, the impact would be disastrous for an economy.
Ironically, a border adjustment would result in a one-time wealth transfer from American to foreign asset holders. A border adjustment would tax the consumption of Americans financed by their holdings of foreign assets and would exempt from the tax base the consumption of foreigners financed by their holdings of American assets. Consequently, the value of foreign assets held by Americans would decline while the value of American assets held by foreigners would appreciate.
The popularity of Keynesian stimulus during the current recession has led to a renewed interest in border adjustments as a way to stimulate aggregate demand. But a border adjustment would not produce permanent changes in trade patterns. In addition, the desire to provide a permanent boost to the economy through a border adjustment constitutes a misunderstanding of Keynesianism. Sound Keynesian policies seek to make output more stable throughout the business cycle by increasing aggregate demand in a downturn and restraining demand during an upturn; they do not permanently boost aggregate demand in a futile effort to permanently raise output.
Supporters of consumption taxation in the United States often rely on misperceptions about border adjustments in order to make their case. There are compelling reasons to adopt a consumption tax in the United States, including simplification and enhanced capital accumulation. The ability to border adjust is immaterial. The border adjustment fallacy should not obscure the real case for consumption taxation.
Alan Viard is resident scholar at the American Enterprise Institute. He was a senior economist at the Federal Reserve Bank of Dallas and an assistant professor of economics at Ohio State University. He has also worked for the Treasury Department’s Office of Tax Analysis, the White House’s Council of Economic Advisers, and the Joint Committee on Taxation of the U.S. Congress. This article was adapted by Amy Roden, a research assistant at AEI, and Scott Ganz, AEI’s program manager for economic policy studies, from a longer paper.
FURTHER READING: Viard recently released Tax Policy Lessons from the 2000s (AEI Press, 2009), a collection of essays which explore the role taxes play in setting policy and their effect on businesses' financial and investment decisions. Findings were discussed at this AEI event.
Image by Darren Wamboldt/the Bergman Group.


WEST LAFAYETTE, Ind. - Even large amounts of manufactured nanoparticles, also known as Buckyballs, don't faze microscopic organisms that are charged with cleaning up the environment, according to Purdue University researchers.
In the first published study to examine Buckyball toxicity on microbes that break down organic substances in wastewater, the scientists used an amount of the nanoparticles on the microbes that was equivalent to pouring 10 pounds of talcum powder on a person. Because high amounts of even normally safe compounds, such as talcum powder, can be toxic, the microbes' resiliency to high Buckyball levels was an important finding, the Purdue investigators said.
The experiment on Buckyballs, which are carbon molecules C60, also led the scientists to develop a better method to determine the impact of nanoparticles on the microbial community.
"It's important to look at the entire microbial community when nanomaterials are introduced because the microbes are all interdependent for survival and growth," said Leila Nyberg, a doctoral student in the School of Civil Engineering and the study's lead author. "If we see a minor change in these microorganisms it could negatively impact ecosystems."
The microbes used in the study live without oxygen and also exist in subsurface soil and the stomachs of ruminant animals, such as cows and goats, where they aid digestion.
"We found no effect by any amount of C60 on the structure or the function of the microbial community over a short time," Nyberg said. "Based on what we know about the properties of C60, this is a realistic model of what would happen if high concentrations of nanoparticles were released into the environment."
The third naturally occurring pure carbon molecule known, Buckyballs are nano-sized, multiple-sided structures that look like soccer balls.
Nyberg and her colleagues Ron Turco and Larry Nies, professors of agronomy and ci
|Contact: Susan A. Steeves|


Shoumita Dasgupta, Ph.D.
Associate Professor of Medicine, Biomedical Genetics
Director of Graduate Studies, Program in Genetics and Genomics
Medical Genetics Course Manager, Boston University School of Medicine
Ph.D. University of California, San Francisco
M.S. University of California, San Francisco
B.S. Massachusetts Institute of Technology
Stanley L. Robbins Award for Excellence in Teaching
The popular press has called the twentieth century “The Century of the Gene.” During this time, genetics came forward as a central discipline in biology, first with the rediscovery of the work of Gregor Mendel at the turn of the century, later with the elucidation of the structure of DNA by Jim Watson and Francis Crick, and more recently with the development of recombinant DNA technologies by Paul Berg and Herb Boyer. These scientific events revolutionized the way we thought about biological problems. Mendel’s contributions led scientists to probe the genetic basis of inheritance while Watson and Crick helped to define the molecular nature of this inheritance. Berg and Boyer developed the tools that allowed scientists to manipulate these molecules of inheritance to more deeply understand their functions. Each of these events has had far-reaching consequences because of the explosion of scientific inquiry it both allowed and inspired.
Currently, scientists of the twenty-first century are poised at the brink of another genetic revolution, this time triggered by the genome projects of organisms from microbes to humans. With the availability of this data, it has become obvious that current computational tools alone are inadequate to fully mine this immense data set. Although the power of current genomic strategies is tremendous, they are not sufficient to determine gene function. Consequently, scientists are seeking to ascertain gene function using two main approaches. First, there is a great effort underway to create new technologies and computational tools to allow for large scale molecular analyses of complex systems. Secondly, these strategies are utilized alongside methods that take advantage of the powerful role of model organisms in helping to determine gene function, an important focus of the Genetics and Genomics department. This global perspective on the intricate networks that govern the machinery of life is causing a shift in the traditional paradigm of identifying the impact of individual genes on any given process. Instead, the revised concept that no gene acts in isolation is more easily explored with these new genomic and bioinformatics tools.
The aim of our program in establishing graduate coursework in Genetics and Genomics is to teach our students to apply the approaches of classical genetics and modern genomics to investigations of the heritable basis of numerous biological traits, the relationships among genes, the regulation of their expression, and the elaborate mechanisms involved in supporting complex biological processes. We want our students to be adept at utilizing hypothesis-driven methods as well as discovery-oriented experimental design styles to explore these problems. The combination of these two tactics will allow our students to systematically and broadly make important contributions to many disciplines of biology. Moreover, it is our goal that our students will also be trained to function as active members of the scientific community who can clearly communicate ideas, critically evaluate biomedical research, and mentor others in scientific scholarship. Towards this end, we offer an array of courses and training opportunities that comprise the Graduate Program in Genetics and Genomics. “Principles of Genetics and Genomics” is a core course that focuses on the use of genetic methods in model organisms for understanding complex biological processes. This course focuses on the ability to use genetic systems to probe these problems, and therefore heavily explores the experimental aspects of these investigations. In addition, we discuss the impact of the genome sequences on the practice of modern science. In this regard, the course will be aimed towards first year PhD students in the biological sciences, but the course is open to anyone wishing to study genetic approaches to biological research. In addition, we use a case study approach to investigate the rich variety of scientific insights gained through genetic studies. As such, it is a core course that serves a diverse, interdisciplinary group of students in many fields from genetics and genomics to bioinformatics to immunology, and many others. Further details on this course and our other exciting courses for graduate and medical students can be found on the course website. This course is one of the foundations for our Graduate Program in Genetics and Genomics, which is designed to bring these same approaches to an entire coordinated curriculum. Our Graduate Program aims to bridge the disciplines of experimental biosciences with computational and genomic approaches. The program consists of laboratory rotations, advanced coursework, and journal clubs in the first year. Subsequently, graduate students will focus on their thesis research, qualifying exams, and a teaching requirement. Additional information on our graduate program can be found on the graduate program website.
The pace of genetic advances during the last century has been unparalleled scientifically, and these discoveries have already made and are poised to make an incredible impact on the practice of medicine. Currently, OMIM (Online Mendelian Inheritance in Man) lists thousands of identified disease genes, and likewise GeneTests lists thousands of diseases for which there are molecular tests. In this course we explore the precise molecular determinants of medical conditions and of human phenotypic variation that are being elucidated on a daily basis. Clearly, a detailed understanding of the genetic basis of human disease will lead to more precise molecular assays and diagnostics, better-targeted treatments, and more efficient treatment plans overall. Moreover, these developments will certainly affect all clinical specialties of the medical field since genetic components have a clear influence on a wide variety of human traits and conditions, from height and developmental birth defects to cancer susceptibility and neurological degeneration. We consider how these rapid advances can be utilized appropriately in a clinical environment as well as what ethical, legal, and societal implications all of these developments hold. This course is offered to first year medical students.


Henry Franklin Battles/ Susan (Monks) Battles
Submitted by: Archie (Bud) and Doris Battles, grandson and wife.
The Henry Franklin Battles and Susan Monks families presumably came from Alabama and settled around Cameron, Indian Territory. Henry Franklin Battles born 12-23-1851, enrolled at Doaksville, Indian Territory and died 2-6-1936 at Gowen, OK. His father was G.W. Battles. Susan (Monks) Battles born 12-23-1856 to F.M. and Susan Monks. She was enrolled in Garris County and died 7-25-1937 at Ashland, OK. It is presumed that around Cameron, Indian Territory is where Henry and Susan met, married and started raising their family of four boys. From there, they moved to Wilburton where they had one girl and two more boys.
They farmed and the children went to a small school southwest of Wilburton. They named it the Battles School. Later, some of the boys went to Jones Academy. Later on, they were enrolled on the Choctaw Rolls and was allotted land around Ashland, Indian Territory. They moved to their land where they farmed and horse raced. Their children had all met, married and had children by this time. All of the grandchildren moved, with most of them going to Salt Plains, Van Horne and Ashland. Their children were:
- William E. born 12-28-1872 and died 1-2-1950. His first wife was named Martha then he married Emma Shaw;
- Finis Marion born 8-19-1878 and died 1-18-1958. He married Maggie Dunlap on 4-29-1906;
- John Marim born 5-22-1881 and died 1-21-1970. His first wife was Cemie Patrick then Annie May Chester;
- George Washington born 8-21-1887 and died 4-5-1962. He married Ola Mae Christian, 10-20-1907;
- Erma E.L. born 12-24-1888 and died 2-26-1975. She married Jim Carter;
- James (Jimmie) Ernest born 8-7-1893 and died 7-27-1974. He married Walsie Akin in 1912;
- Lester born 12-24-1896 and died 12-19-1965. His first wife was Nellie Parnell then he married Mandy Owensby;
- Pearl Clementine. Clementine was married to #3 son, John. Children of George Washington Battles and Minnie Ola (Christian) Battles are:
Venita Jewell (Battles) Collie, born 11-13-1908 at Ashland. She married Jim Colie and there were no children;
Oran, born 8-13-1910 at Ashland. His first wife was Birtha ? and they had one son, Charles; Tollie (Dutch), born 6-20-1920 at Ashland and died 12-4-1953. He married Alice? And they had four children:
Mary Jo, Richard, Samuel and Linda; Archie Monroe (Bud), born 7-14-1914 at Wardville. He married Willie Doris Lenox, 12-30-1937 and they had two sons;
Kenneth Hoyt and Walter Roy. Kenneth was born 12-3-1939 and married Mary Alice Hogan. Walker Roy was born 11-24-1942. His first wife was Wilma Sturgeion then he married Gwen Pola Gormly.
Olen, born 11-22-1916 at Ashland. His wife was Joan; Henry Franklin (Dink), born 8-4-1914 at Ashland and died 3-11-1942. He had no children; Lucille, born 12-30-1920 at Ashland. She married Loyd Faris and they had two children, Shirley and Keith; Jake, born 4-19-1923 at Gowen. His wife’s name was Jean and they had two girls and one boy; Pauline, born 6-23-1928 at Wardville. She married J.B. Dave and they had one child, Pamela; George Washington, Jr. (Sam), born 7-15-1930 at Ashland. His wife’s name was Wanda and they had two children, Machala and Rodney. All of the children were born in Oklahoma within a few miles of each other.


WHAT YOU SHOULD KNOW:
Alcohol intoxication is a harmful physical condition caused when you drink more alcohol than your body can handle. It is also called ethanol poisoning, or being drunk.
AFTER YOU LEAVE:
You may be given medicine to manage the signs and symptoms of alcohol intoxication. Take your medicine as directed. Contact your primary healthcare provider if you think your medicine is not helping or if you have side effects. Tell him if you are allergic to any medicine. Keep a list of the medicines, vitamins, and herbs you take. Include the amounts, and when and why you take them. Bring the list or the pill bottles to follow-up visits. Keep the list with you in case of emergency.
Follow up with your primary healthcare provider as directed:
Write down your questions so you remember to ask them during your visits.
Limit or avoid alcohol:
Men should not have more than 2 drinks per day. Women should not have more than 1 drink per day. A drink is 12 ounces of beer, 5 ounces of wine, or 1½ ounces of liquor.
Do not drive or operate machines when you drink alcohol:
Make sure you always have someone to drive you when you drink alcohol.
Learn ways to manage stress. Deep breathing, meditation, and listening to music may help you cope with stressful events. Talk to your caregiver about other ways to manage stress.
For more information:
- Alcoholics Anonymous
Web Address: http://www.alcoholics-anonymous.org.
Contact your primary healthcare provider if:
- You need help to stop drinking alcohol.
- You have trouble with work or school because you drink too much alcohol.
- You have physical or verbal fights because of alcohol.
- You have questions or concerns about your condition or care.
Seek care immediately or call 911 if:
- You have sudden trouble breathing or chest pain.
- You have a seizure.
- You feel sad enough to harm yourself or others.
- You have hallucinations (you see or hear things that are not real).
- You cannot stop vomiting.
- You were in an accident because of alcohol.
© 2013 Truven Health Analytics Inc. Information is for End User's use only and may not be sold, redistributed or otherwise used for commercial purposes. All illustrations and images included in CareNotes® are the copyrighted property of the Blausen Databases or Truven Health Analytics.
The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.


Sea ice is frozen seawater that floats on the ocean surface. Blanketing millions of square kilometers, sea ice forms and melts with the polar seasons, affecting both human activity and biological habitat. In the Arctic, some sea ice persists year after year, whereas almost all Southern Ocean or Antarctic sea ice is "seasonal ice," meaning it melts away and reforms annually. While both Arctic and Antarctic ice are of vital importance to the marine mammals and birds for which they are habitats, sea ice in the Arctic appears to play a more crucial role in regulating climate.
Because they are composed of ice originating from glaciers, icebergs are not considered sea ice. Most of the icebergs infesting North Atlantic shipping lanes originate from Greenland glaciers.
Global Sea Ice Extent and Concentration: What sensors on satellites are telling us about sea ice
Sea ice regulates exchanges of heat, moisture and salinity in the polar oceans. It insulates the relatively warm ocean water from the cold polar atmosphere except where cracks, or leads, in the ice allow exchange of heat and water vapor from ocean to atmosphere in winter. The number of leads determines where and how much heat and water are lost to the atmosphere, which may affect local cloud cover and precipitation.
The seasonal sea ice cycle affects both human activities and biological habitats. For example, companies shipping raw materials such as oil or coal out of the Arctic must work quickly during periods of low ice concentration, navigating their ships towards openings in the ice and away from treacherous multi-year ice that has accumulated over several years. Many arctic mammals, such as polar bears, seals, and walruses, depend on the sea ice for their habitat. These species hunt, feed, and breed on the ice. Studies of polar bear populations indicate that declining sea ice is likely to decrease polar bear numbers, perhaps substantially (Stirling and Parkinson 2006).
Ice thickness, its spatial extent, and the fraction of open water within the ice pack can vary rapidly and profoundly in response to weather and climate. Sea ice typically covers about 14 to 16 million square kilometers in late winter in the Arctic and 17 to 20 million square kilometers in the Antarctic Southern Ocean. The seasonal decrease is much larger in the Antarctic, with only about three to four million square kilometers remaining at summer's end, compared to approximately seven to nine million square kilometers in the Arctic. These maps provide examples of late winter and late summer ice cover in the two hemispheres.
Monitoring sea ice
Passive microwave satellite data represent the best method to monitor sea ice because of the ability to show data through most clouds and during darkness. Passive microwave data allow scientists to monitor the inter-annual variations and trends in sea ice cover. Observations of polar oceans derived from these instruments are essential for tracking the ice edge, estimating sea ice concentrations, and classifying sea ice types. In addition to the practical use of this information for shipping and transport, these data add to the meteorological knowledge base required for better understanding climate.
Decline in Arctic sea ice extent
Passive microwave satellite data reveal that, since 1979, winter Arctic ice extent has decreased about 3.6 percent per decade (Meier et al. 2006). Antarctic ice extent is increasing (Cavalieri et al. 2003), but the trend is small.
Satellite data from the SMMR and SSM/I instruments have been combined with earlier observations from ice charts and other sources to yield a time series of Arctic ice extent from the early 1900s onward. While the pre-satellite records are not as reliable, their trends are in good general agreement with the satellite record and indicate that Arctic sea ice extent has been declining since at least the early 1950s.
In recent years, satellite data have indicated an even more dramatic reduction in regional ice cover. In September 2002, sea ice in the Arctic reached a record minimum (Serreze et al. 2003), 4 percent lower than any previous September since 1978, and 14 percent lower than the 1979-2000 mean. In the past, a low ice year would be followed by a rebound to near-normal conditions, but 2002 was followed by two more low-ice years, both of which almost matched the 2002 record. Taking these three years into account, the September ice extent trend for 1979-2004 declined by 7.7 percent per decade (Stroeve et al. 2005). The year 2005 set a new record, dropping the estimated decline in end-of-summer Arctic sea ice to approximately 8 percent per decade. Although sea ice did not set a new record low in 2006, it did fall below normal for the fifth consecutive year. In 2007, sea ice broke all prior satellite records, reaching a record low a month before the end of melt season. Through 2007, the September decline trend is now over 10 percent per decade. (For current sea ice trends, visit NSIDC's Sea Ice Index Cryospheric Climate Indicators.)
Combined with record low summertime extent, Arctic sea ice exhibited a new pattern of poor winter recovery. In the past, a low-ice year would be followed by a rebound to near-normal conditions, but 2002 was followed by two more low-ice years, both of which almost matched the 2002 record (see Arctic Sea Ice Decline Continues). Although wintertime recovery of Arctic sea ice improved somewhat after 2006, wintertime extents have remained well below the long-term average.
Decline in Arctic Sea Ice Thickness
Sea ice thickness has likewise shown substantial decline in recent decades (Rothrock et al. 1999). Using data from submarine cruises, Rothrock and collaborators determined that the mean ice draft at the end of the melt season in the Arctic has decreased by about 1.3 meters between the 1950s and the 1990s.
Estimates based on measurements taken by NASA's ICESat laser altimeter, first-year ice that formed after the autumn of 2007 had a mean thickness of 1.6 meters. The ice formed relatively late in the autumn of 2007, and NSIDC researchers had actually anticipated this first-year ice to be thinner, but it nearly equaled the thickness of 2006 and 2007. Snow accumulation on sea ice helps insulate the ice from frigid air overhead, so sparse snowfall during the winter of 2007-2008 might have actually accelerated the sea ice's growth.
Greenhouse gases emitted through human activities and the resulting increase in global mean temperatures are the most likely underlying cause of the sea ice decline, but the direct cause is a complicated combination of factors resulting from the warming, and from climate variability. The Arctic Oscillation (AO) is a see-saw pattern of alternating atmospheric pressure at polar and mid-latitudes. The positive phase produces a strong polar vortex, with the mid-latitude jet stream shifted northward. The negative phase produces the opposite conditions. From the 1950s to the 1980s, the AO flipped between positive and negative phases, but it entered a strong positive pattern between 1989 and 1995. So the acceleration in the sea ice decline since the mid 1990s may have been partly triggered by the strongly positive AO mode during the preceding years (Rigor et al. 2002 and Rigor and Wallace 2004) that flushed older, thicker ice out of the Arctic, but other factors also played a role.
Since the mid-1990s, the AO has largely been a neutral or negative phase, and the late 1990s and early 2000s brought a weakening of the Beaufort Gyre. However, the longevity of ice in the gyre began to change as a result of warming along the Alaskan and Siberian coasts. In the past, sea ice in this gyre could remain in the Arctic for many years, thickening over time. Beginning in the late 1990s, sea ice began melting in the southern arm of the gyre, thanks to warmer air temperatures and more extensive summer melt north of Alaska and Siberia. Moreover, ice movement out of the Arctic through Fram Strait continued at a high rate despite the change in the AO. Thus warming conditions and wind patterns have been the main drivers of the steeper decline since the late 1990s. Sea ice may not be able to recover under the current persistently warm conditions, and a tipping point may have been passed where the Arctic will eventually be ice-free during at least part of the summer (Lindsay and Zhang 2005).
Examination of the long-term satellite record dating back to 1979 and earlier records dating back to the 1950s indicate that spring melt seasons have started earlier and continued for a longer period throughout the year (Serreze et al. 2007). Even more disquieting, comparison of actual Arctic sea ice decline to IPCC AR4 projections show that observed ice loss is faster than any of the IPCC AR4 models have predicted (Stroeve et al. 2007).
Disclaimer: This article is taken wholly from, or contains information that was originally published by, the National Snow and Ice Data Center. Topic editors and authors for the Encyclopedia of Earth may have edited its content or added new information. The use of information from the National Snow and Ice Data Center should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content.


This release is available in French.
Your blood and the level of a hormone in your spit could reveal if you're on the point of burnout, according to research undertaken by Dr. Sonia Lupien and Robert-Paul Juster of the Centre for Studies on Human Stress of Louis-H. Lafontaine Hospital and the University of Montreal. In addition to professional and personal suffering, burnout puts distressed workers at further risk of physical and psychological problems if ignored. This is significant, as burnout, clinical depression, or anxiety related to the workplace affects at least 10% of North Americans and Europeans, according to estimates prepared by the International Labor Organization.
"We hypothesized that healthy workers with chronic stress and with mild burnout symptoms would have worse physiological dysregulations and lower cortisol levels – a profile consistent with burnout," Juster explained. Cortisol is a stress hormone involved in our bodies stress response and naturally as part of our body's daily rhythm. Cortisol levels are often high in people suffering from depression, while it tends to be low in cases of burnout. Too much cortisol can be as bad as too little when it comes to both mental and physical health.
Chronic stress and misbalanced cortisol levels can exert a kind of domino effect on connected biological systems. The term "allostatic load" represents the physiological problems or 'wear and tear' that ensue in these different systems related to risks for diabetes, cardiovascular disease, and immune problems. By looking at various factors such as insulin, sugar, cholesterol, blood pressure, and inflammation, an allostatic load index can be constructed and then used to detect problems before they occur. "The strength of the allostatic load model is its flexible inclusion of numerous biological systems that get strained by chronic stress. Complementary use of saliva samples and validated questionnaires allows us to go beyond measuring susceptibilities to, say, metabolic syndromes or heart problems, but also into the realm of mental health," Juster said.
The results of this first pilot study were obtained by testing thirty middle-aged participants. In addition to undergoing routine blood measures that assessed allostatic load, participants were instructed to collect saliva at home and during a laboratory paradigm. They also filled out questionnaires related to their current stress levels as well as symptoms of depression and burnout.
This research is part of a greater effort to develop personalized medicine in this field. Personalized medicine targets the customization of treatment according to the needs of the individual. "In an effort to advance person-centered approaches in prevention and treatment strategies, we have to investigate the biopsychosocial signatures of specific diseases," Lupien said. "For conditions like burnout where we have no consensus on diagnostic criteria and where there is overlap with symptoms of depression, it is essential to use multiple methods of analysis. One potential signature of burnout appears to be fatigued production of the stress hormone cortisol and dysregulations of the physiological systems that interact with this stress hormone."
Critically, people with burnout are often treated with anti-depressant medications that lower cortisol levels. If cortisol is already lower than it should be, this course of treatment could represent a therapeutic mistake. "The use of an allostatic load index gives researchers and clinicians a window to see how chronic stress is straining the person. In the future, we need studies that track people over time to determine whether this profile of low cortisol and physiological dysregulations is indeed burnout's autograph. If so, science will be one step closer to helping distressed workers before they burn out," Juster noted.
The research was published in Psychoneuroendocrinology and received funding from the Canadian Institutes of Health Research. Dr. Sonia Lupien is Scientific Director of Fernand-Seguin Research Centre of Louis–H. Lafontaine Hospital and is an associate professor with the Department of Psychiatry at Université de Montréal. Dr. Lupien is the Founder and Director of the Centre for Studies on Human Stress. She also holds a Senior Investigator Chair on Sex, Gender and Mental Health from the Canadian Institute of Gender and Health (IGH). Juster is affiliated with the Fernand-Seguin Research Centre of Louis-H. Lafontaine Hospital and the Centre for Studies on Human Stress. He's a Ph.D. candidate in the Department of Neurology and Neurosurgery at McGill University.
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.


By the HELP Committee and Havre Public Schools
Summer can be a risky time for teens. More teens try marijuana for the first time in June and July than any other time of the year, according to a new report from the Substance Abuse and Mental Health Services Administration. Each day in June and July, more than 6,300 youths try marijuana for the first time. That's 40 percent more per day than during the rest of the year. The number of new underage drinkers and cigarette smokers also jumps during the summer months.
The increase in new marijuana use is likely due to teens having more unsupervised and unstructured time in the summer. Research shows that unmonitored teens are four times more likely to use marijuana or engage in other risky behaviors.
"Youth marijuana use has declined by 11 percent over the past two years. Despite the good news, the battle of reducing teen drug use is not yet over," said John P. Walters, director of the Office of National Drug Control Policy. "Kids may equate summer with freedom, but for parents, it's when they need to be even more involved in their teens' lives. By keeping teens busy, knowing who they're with and making sure they're supervised, parents can help prevent their teen's summer from going to pot."
And marijuana is more harmful than some parents think. Marijuana can be addictive and lead to a host of health, social and behavioral problems at a crucial time in kids' lives - when their bodies and brains are still developing. Marijuana use damages lungs, impairs learning and decreases motivation. Kids who use marijuana in early adolescence are more likely to engage in risky behaviors, such as delinquency, engaging in sexual activity, driving while high, or riding with someone who is under the influence of drugs or alcohol. They are also more likely to perceive drugs as not harmful and to have more friends who exhibit deviant behavior.
Havre kids are at greatest risk between 11 and 16 years of age.
Each year, Havre Public Schools administers the Youth Risk Behavior Surveillance assessment to students at the high school, alternative school and middle school.
Four of the assessment questions address marijuana use. While these questions do not address which season of the year marijuana was used, students are asked "How old were you when you tried marijuana for the first time?" Nearly 16 percent of respondents were 11 or 12 years old when they used marijuana for the first time. Just over 19 percent of respondents were 13 or 14 years old. More than 15 percent were 15 or 16 years old. At 17 years of age, the incidence of first-time marijuana use dropped to 2 percent.
Canterbury Consultive Services of Helena administers the YRBS assessment. In its executive summary, the Canterbury researchers asserted that "frequency of alcohol and drug abuse risk behaviors as reported by Havre Middle School respondents were generally consistent with statewide respondents with little variation over the four-year reporting period." However, the frequency of these same behaviors "as reported by Havre High School respondents were consistently higher than statewide respondents. With the exception of alcohol and cocaine, reported usage apparently increased during the four-year reporting period."
Sadly, these findings show that, in general, Havre kids experiment with some risky behaviors at a younger age and continue these risky behaviors throughout their youth at a higher rate than other Montana children. This should prompt parents to maintain close ties with and supervision of their children throughout adolescence, even though adolescent children desire, seek and need increasing freedom. It can be a tough balancing act for any parent.
So how can you stop your teen's summer from going to pot? Here is a drug-free checklist:
Set rules. Have you set clear rules and let your teen know that marijuana use is unacceptable?
Set limits with clear consequences for breaking them. Be sure to balance this with praise and rewards for good behavior.
Understand and communicate. Have you talked to your teen in the past month about the harmful physical, mental and social effects of marijuana and other illicit drugs on young users?
Young people who learn about the risks of drugs at home are up to 50 percent less likely to try drugs than their peers who learn nothing from their parents. Look for teachable moments in everyday life to keep the conversation ongoing.
Monitor your teen's activities and behaviors. Have you checked to see where your teen is, who he is with, and what he is doing?
Teens who are not regularly monitored by their parents are four times more likely to use drugs. Check up on your teens to make sure they are where they say they are.
Make sure you stay involved in your teen's life Have you talked to your teen's coach, employer and friends lately?
Stay in touch with the adult supervisors of your child (camp counselors, coaches, employers) and have them inform you of any changes in your teen. Parents of teens with summer jobs still need to know how their teens are spending disposable income, what type of workplace setting they are in, and who they are working with.
Engage your teen in summer activities. Have you helped plan activities to keep your teen busy?
Teens who report they are "often bored" are 50 percent more likely to smoke, drink, get drunk and use illegal drugs than teens who aren't. Teens who are involved in constructive and adult-supervised activities are less likely to use drugs.
Other adults who influence teens, such as camp counselors, coaches, physicians and employers, can and do play a vital role in keeping teens drug-free during the summer. These adults are well-positioned to reach teens with marijuana-prevention messages, and, just by being role models or mentors, they help prevent drug use.
Have you planned a family activity with your teen in the coming weeks, such as going to the movies, taking a walk or sharing a meal?
Teens who spend time, talk and have a close relationship with their parents are much less likely to drink, take drugs or have sex. Two-thirds of youth ages 13 to 17 say fear of upsetting their parents or losing the respect of family and friends is one of the main reasons they don't smoke marijuana or use other drugs. This proves that parents are still the most powerful influence on their teen when it comes to drugs.
The HELP Committee and Boys & Girls Club of the Hi-Line is committed to supporting a drug-free lifestyle for everyone in the community. For more information on this or related topics, call 265-6206.