User:Wasabe3543

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Nothin' to see here.

I'm a man, and I'm torn between vengeance and fashion

Deadly cuteness

cutesie patootsie!!!!!11

OMG so cutesie!!!!!11

Stealth cutesies!!!!11

Conservation status

Koalas at the Lone Pine Koala Sanctuary, Queensland

The Koala was hunted almost to extinction in the early 20th century, largely for its fur. In recent years, some colonies have been hard hit by disease, especially chlamydia. The Koala requires large areas of healthy, connected forest and will travel long distances along tree corridors in search of new territory and mates. The ever-increasing human population of the coastal parts of the continent continues to cut these corridors by agricultural and residential development, forestry and road-building, marooning Koala colonies in decreasing areas of bush. The Australian Koala Foundation has mapped 40,000 sq.km. of land for Koala habitat and claims it has strong evidence to suggest wild Koala populations are in serious decline throughout the species natural range. Although the species covers a massive area, only 'pieces' of Koala habitat remain. These pieces need to be managed, protected and restored in a coordinated way. Presently, many are being lost to weeds, cleared for agriculture, or carved up by developers. Other threats come from logging, poor management, attacks from feral and domestic animals, disease and roads.

In contrast to the situation on much of the mainland, where populations are declining, the Koalas of many island and isolated populations have reached what some have described as "plague" proportions. On Kangaroo Island in South Australia, Koalas introduced some 90 years ago have thrived in the absence of predators and competition. Combined with an inability to migrate to new areas, this has caused the Koala populations to become unsustainable and threaten the Island's unique ecology. In particular, species of Manna Gum, native to the island, are being stripped by Koalas at a rate faster than they can regenerate, endangering local birds and invertebrates that rely on them, and causing the extinction of at least one isolated population of manna. Koala numbers are estimated at over 30,000, with ecologists suggesting that the Island can sustain 10,000 at most. Although culling has been suggested as a means to reduce Koala numbers, with the South Australian Government seriously considering such in 1996, this has met with fierce opposition both domestically and internationally, and the species remains protected. The popularity of the Koala has made the possibility of a cull politically improbable, with any negative perception likely to impact tourism and a government's electability. In place of a cull, sterilisation and translocation programmes have had only limited success in reducing numbers thus far, and remain expensive. There is evidence that Koalas relocated to the mainland have difficulty establishing themselves in the different circumstances. A mooted alternative to the complex sterilisation method, wherein the animal must first be captured, are hormonal implants that can be injected via darts.

The Koala inhabits four Australian states. Under state legislation, the species is listed as:

• Queensland - Common, or "Least Concern Wildlife" throughout the state, except in the relatively small South East Queensland Bioregion, where it is listed as Vulnerable.^[9]
• New South Wales - listed at a state scale as vulnerable, but varying regionally from "secure" to "locally extinct".^[10]
• South Australia - classified as Rare.^[11]
• Victoria - The koala population in Victoria is considered "large and thriving".^[12]

A review of the species national conservation status concluded that the koala are not threatened at a national scale, with a population that numbers in the hundreds of thousands.^[13] This was the third review undertaken by the federal government that came to this conclusion. The IUCN lists the species as "Lower Risk / Near Threatened".^[2]

As with most native Australian animals, the Koala cannot legally be kept as a pet in Australia without a permit.^[14]

Ecology and behaviour

Koala eating eucalyptus leaves

The Koala lives almost entirely on eucalypt leaves. This is likely to be an evolutionary adaptation that takes advantage of an otherwise unfilled ecological niche, since eucalypt leaves are low in protein, high in indigestible substances, and contain phenolic and terpene compounds that are toxic to most species. Like wombats and sloths, the Koala has a very low metabolic rate for a mammal and rests motionless for about 19 hours a day, sleeping most of that time. Koalas that are disturbed are known to be violent, their teeth and claws capable of providing considerable injury to humans; special handling requirements are as such applicable.^[7] Handling of koalas has been a source of political contention due to these risks, which can also cause harm to the koala as well. ^[8]Koalas spend about three of their five active hours eating. Feeding occurs at any time of day, but usually at night. An average Koala eats 500 grams of eucalypt leaves each day, chewing them in its powerful jaws to a very fine paste before swallowing. The liver deactivates the toxic components ready for excretion, and the hind gut (especially the caecum) is greatly enlarged to extract the maximum amount of nutrient from the poor quality diet. Much of this is done through bacterial fermentation: when young are being weaned, the mother passes unusually soft faeces, called pap, which is rich in these bacteria, thus passing these essential digestive aids on to her offspring. The Koala will eat the leaves of a wide range of eucalypts, and occasionally even some non-eucalypt species, but it has firm preferences for particular varieties. These preferences vary from one region to another: in the south Manna Gum, Blue Gum and Swamp Gum are favoured; Grey Gum and Tallowwood are important in the north, and the ubiquitous River Red Gum of the isolated seasonal swamps and watercourses that meander across the dry inland plains allows the Koala to exist in surprisingly arid areas. Many factors determine which of the 800 species of eucalypt trees the Koala eats. Among trees of their favourite species, however, the major factor that determines which individual trees the Koala chooses is the concentration of a group of phenolic toxins called formylated phloroglucinol compounds.

Life cycle

Females reach maturity at 2 to 3 years of age, males at 3 to 4 years. If healthy, a female Koala can produce one young each year for about 12 years. Gestation is 35 days; twins are very rare. Mating normally occurs between December and March, the Southern Hemisphere's summer.

A baby Koala is referred to as a joey and is hairless, blind, and earless. At birth the joey, only a quarter of an inch long, crawls into the downward-facing pouch on the mother's belly (which is closed by a drawstring-like muscle that the mother can tighten at will) and attaches itself to one of the two teats. Koalas retain the rearward-facing pouch of their terrestrial vomaboid ancestors. Young remain hidden in the pouch for about six months, only feeding on milk. During this time they grow ears, eyes, and fur. The joey then begins to explore outside of the pouch. At about this stage it begins to consume small quantities of the semi-liquid form of the mother’s excrement called "pap" in order to inoculate its gut with the microbes necessary to digest eucalypt leaves.^{[citation needed]} The baby Koala will remain with the mother for another six months or so, riding on her back, and feeding on both milk and eucalypt leaves until weaning is complete at about 12 months of age. Young females disperse to nearby areas at that time; young males often stay in the mother's home range until they are two or three years old.

Names

The word "koala" comes from the Dharuk word gula.^[3] Closely related words appear in other Australian Aboriginal languages, including:

• The Ngunnawal of the Canberra region also call it gula.
• In the Blue Mountains of New South Wales, Aborigines called Koalas by the word Cullawines.
• In the Murray Region, Aborigines called Koalas by the word Karbors.
• Other Aboriginal names for Koalas include: Bangaroos, Koolewongs, Narnagoons and Cholos. ^[4].

It is commonly said that the common name 'Koala' is an Aboriginal word meaning "no drink" although there is no evidence to support this. Koalas do drink water, but only rarely, due to their diet consisting of eucalypt leaves, which contain sufficient water to obviate the need for the Koala to descend to ground level to drink.

Early European settlers to Australia called the Koala the Native Bear, and the Koala is still sometimes called the Koala Bear, but it is not a member of the bear family. It is not even a placental mammal (which most mammals are) - it is a marsupial. The Koala's scientific name (Phascolarctos cinereus) comes from the Greek: phaskolos meaning "pouch" and; arktos meaning "bear". The cinereus epithet is Latin and means "ash-coloured".

Qualcomm suffers setback in patent duel

Beginning of book

The book begins at the home of Lucius Malfoy, with Snape and a Ministry official, Yaxley, informing Lord Voldemort of the date Harry Potter intends to leave the Dursleys' house. Voldemort borrows Lucius' wand, because his own is ineffective against Harry's wand (due to the wands sharing twin cores ). Voldemort plans to kill Harry when he is being moved to a new safe place, which must happen when he turns seventeen and his safety with the Dursleys expires. Yaxley claims that Harry will be moved on the 30th, when he turns seventeen; however, Snape disagrees, saying that he will be moved a week earlier.

Snape's claim is true; Harry is leaving before he turns 17. On the night he is to leave the Dursleys' home, he reads an obituary of Albus Dumbledore, written by Dumbledore's friend Elphias "Dogbreath" Doge. Harry learns about Dumbledore's family including his brother Aberforth and sister Ariana through a stinging article by Rita Skeeter examining the family's convoluted history, and he regrets not having asked Dumbledore more about his past.

With the Dursleys escorted to safety by a pair of wizards, the Order of the Phoenix arrives to sneak Harry out of his house. Despite an attempted decoy involving six younger members of the Order of the Phoenix taking a Polyjuice potion to make themselves look like him, Harry, accompanied by Hagrid, is correctly identified by his "trademark" disarming spell (as he dislikes hurting people) and attacked by Voldemort and his Death Eaters. Harry's wand, surprisingly, still reacts with Voldemort's new, borrowed wand, destroying it. Hedwig, Harry's owl, is killed by a stray Killing Curse. After narrowly escaping, Harry and the Order eventually reach the Weasley residence, The Burrow. George Weasley has lost an ear due to the Sectumsempra curse cast by Snape, and Alastor Moody had been killed by Voldemort himself. Reacting to Voldemort's anger at his escape, Harry has a vision of the Dark Lord interrogating Ollivander the wand maker over why his borrowed wand still reacted with Harry's.

A few days later, the Minister of Magic arrives at The Burrow to give Harry, Ron, and Hermione bequests from Dumbledore's will. Ron is given Dumbledore's Deluminator (or "Put-Outer"), with the power to capture lights, Hermione receives a book of children's stories written in Ancient Runes, and Harry inherits Godric Gryffindor's sword and the first Snitch that Harry had ever caught. The Ministry withholds the sword after investigating all the items. The three try to discover the purpose of the bequests without success; Harry only manages to find an inscription on the Snitch: "I open at the close."

Near the end of Bill Weasley and Fleur Delacour's wedding reception, news comes that Voldemort has taken over the Ministry of Magic, and that Rufus Scrimgeour is dead, replaced by Pius Thicknesse, who is Imperiused. The Death Eaters attack again, trying to capture the now disguised Potter. The three flee the wedding, first to a Muggle café, but after being attacked by Death Eaters again, to 12 Grimmauld Place, the former home of the Black family. There, the three realize that Regulus Arcturus Black was the R.A.B. who removed the locket from the lake, dying in the attempt. However, the house elf Kreacher, after some persuasion, tells them that Mundungus Fletcher has stolen the locket from the house. Fletcher is caught by Kreacher and unwillingly reveals that he has passed it on to Dolores Umbridge as a bribe to keep him from being arrested.

Pre-Nanotechnology

Humans have unwittingly employed nanotechnology for thousands of years, for example in making steel and in vulcanizing rubber. Both of these processes rely on the properties of stochastically-formed atomic ensembles mere nanometers in size, and are distinguished from chemistry in that they don't rely on the properties of individual molecules. But the development of the body of concepts now subsumed under the term nanotechnology has been slower.

The first mention of some of the distinguishing concepts in nanotechnology (but predating use of that name) was in 1867 by James Clerk Maxwell when he proposed as a thought experiment a tiny entity known as Maxwell's Demon able to handle individual molecules.

In the 1920's, Irving Langmuir and Katharine B. Blodgett introduced the concept of a monolayer, a layer of material one molecule thick. Langmuir won a Nobel Prize in chemistry for his work

Further reading

• Geoffrey Hunt and Michael Mehta (2006), Nanotechnology: Risk, Ethics and Law. London: Earthscan Books.
• Hari Singh Nalwa (2004), Encyclopedia of Nanoscience and Nanotechnology (10-Volume Set), American Scientific Publishers. ISBN 1-58883-001-2
• Michael Rieth and Wolfram Schommers (2006), Handbook of Theoretical and Computational Nanotechnology (10-Volume Set), American Scientific Publishers. ISBN 1-58883-042-X
• Yuliang Zhao and Hari Singh Nalwa (2007), Nanotoxicology, American Scientific Publishers. ISBN 1-58883-088-8
• Hari Singh Nalwa and Thomas Webster (2007), Cancer Nanotechnology, American Scientific Publishers. ISBN 1-58883-071-3

• Roger Smith, Nanotechnology: A Brief Technology Analysis, CTOnet.org, 2004. [34]
• Arius Tolstoshev, Nanotechnology: Assessing the Environmental Risks for Australia, Earth Policy Centre, September 2006. [35]
• Hunt, G & Mehta, M (eds) Nanotechnology: Risk, Ethics & Law. Earthscan, London 2006.
• Friends of the Earth, "Nanotechnology, sunscreens and cosmetics: Small ingredients, big risks", 2006. [36]

Royal Navy Discoveries

Over the next three years, Dr. Donald's team conducted literally hundreds of exposures on human volunteers (remember, there was a war on). This series of studies formed the basis of what we know about CNS oxygen toxicity, namely:

Oxtox - What Is It?

Oxygen toxicity is a time duration phenomenon: that is, both time and partial pressure play a role. If an oxygen partial pressure of 2 ata is breathed for a few minutes, there would probably not be any problem. But, breathing it for an hour, might cause problems. This is why oxygen exposure limits are given as partial pressure/time limits. As the partial pressure gets higher, the recommended exposure time gets shorter.

What kind of problems might breathing a high oxygen partial pressure cause? It is the lungs and the brain which are the target organs of major concern in diving oxygen toxicity. Oxygen toxicity in the lungs (pulmonary oxygen toxicity) is like getting a bad case of the flu, but it will rarely cause permanent damage. The most common situation in which pulmonary oxygen toxicity might occur is during very long recompression treatments.

Oxygen toxicity of the brain, commonly referred to as central nervous system (CNS) oxygen toxicity, is different. It can occur during actual diving, and when it does, it can ruin your day - and possibly more. Some symptoms of CNS oxygen toxicity include flashing lights in front of the eyes, tunnel vision, loud ringing or roaring in the ear (tinnitus), confusion, lethargy, a feeling of nausea or vertigo, areas of numbness or tingling, and muscular twitching, especially of the lips.

These CNS symptoms are inconvenient, and a warning to change to a breathing gas with a lower oxygen partial pressure as soon as possible, but do not put the diver at risk of injury at this point. The big daddy of CNS symptoms does, however. It is the full-blown grand mal convulsion. During a convulsion, a diver will thrash about, perhaps bang his head into something hard, or if underwater, may lose his mouthpiece. The result can be trauma or drowning.

The good news is that convulsions are rare; the bad news is that all the inconvenient CNS symptoms noted above do not always provide warning of an impending convulsion. In some cases, a convulsion may occur without any warning at all. One more piece of good news: the convulsion in and of itself is not harmful, so if you don't crack your head or drown, you should have no permanent damage.

By now you're probably asking where these dire descriptions are leading.

To a better understanding, we hope, of diving on nitrox. As air-breathing sport divers need to know about decompression sickness (DCS), divers using high oxygen in nitrogen mixtures (nitrox) need to know about oxygen toxicity. (To read more about nitrox, see Alert Diver, January/February 1996, p.32.)

Both decompression sickness and oxygen toxicity are rare occurrences; they can be made rarer with good diving practices. With DCS, it's using your table or computer conservatively and keeping the ascent rate down. With oxtox, it's paying attention to the partial pressure and the amount of exposure time.

The main thing we're discussing here is CNS oxygen toxicity, because this is the most dangerous kind. Lung oxygen toxicity is unlikely to be a problem for recreational divers, so it will be mentioned only in passing.

Remember Partial Pressure?

The partial pressure of a gas is a measure of the number of molecules in a given volume - the molecular concentration. The physiological effects of a gas are due mainly to its partial pressure, no matter what the total pressure is.

If a gas has only one component, say 100-percent oxygen, the partial pressure and the pressure are the same. If there is a gas mix, then the partial pressure is the gas fraction times the total pressure. A 50 percent oxygen-in-nitrogen mix has an oxygen partial pressure (pO2) of 1.0 atmosphere absolute (ata) at a depth of 33 feet / 10 meters where the total pressure is 2 ata.

At this depth the 50 percent oxygen would have the same physiological effect as 100 percent oxygen at the surface. Breathing a 100 percent oxygen mix at a depth of 33 feet / 10 meters (2 ata total pressure) would be equivalent to breathing the 50 percent mix at 132 feet / 40 meters (4 ata total pressure).

DAN Medical Services

DAN makes it easy for you to find answers to your diving medical questions. However, the complexities surrounding most medical issues demand personal attention. Therefore, the information presented here should always be used in conjunction with advice from your personal diving physician.

For non-emergency medical questions, you can talk to a DAN Medic by calling +1-919-684-2948 (Monday through Friday, 9am to 5pm EST). If you prefer to submit your question via e-mail, you can send it directly to a DAN Medic.

If you believe that you might have signs or symptoms of decompression illness, please call DAN's Diving Emergency Hotline IMMEDIATELY at +1-919-684-8111 or +1-919-684-4326 (collect). This hotline is staffed 24 hours a day, 365 days per year.

DAN Services, Inc. is a for-profit, wholly-owned subsidiary of Divers Alert Network (DAN), a non-profit 501(c)(3) corporation. DAN's mission is to provide emergency medical advice and assistance for underwater diving and aquatic injuries, to work to prevent injuries, and to promote diving and aquatic safety, research and education. DAN Services, Inc. was formed to assist DAN in fulfilling its mission.

As a for-profit subsidiary, DAN Services, Inc. pays taxes and provides additional benefits to its members such as its Insurance Services. These, and other programs, generate income through royalties and licensing agreements that help DAN fund continuing research in recreational dive safety.

DAN Services, Inc. is a licensed insurance agency and Third Party Administrator (TPA) that sells a variety of insurance products to members of Divers Alert Network (DAN) within the United States. It also contracts with other Insurance Companies to provide those insurance products that DAN members have requested.

There is a growing body of scientific evidence which demonstrates the potential for some nanomaterials to be toxic to humans or the environment [3], [4], [5]. The smaller a particle, the greater its surface area to volume ratio and the higher its chemical reactivity and biological activity. The greater chemical reactivity of nanomaterials results in increased production of reactive oxygen species (ROS), including free radicals [6]. ROS production has been found in a diverse range of nanomaterials including carbon fullerenes, carbon nanotubes and nanoparticle metal oxides. ROS and free radical production is one of the primary mechanisms of nanoparticle toxicity; it may result in oxidative stress, inflammation, and consequent damage to proteins, membranes and DNA [7].

The extremely small size of nanomaterials also means that they are much more readily taken up by the human body than larger sized particles. Nanomaterials are able to cross biological membranes and access cells, tissues and organs that larger-sized particles normally cannot [8]. Nanomaterials can gain access to the blood stream following inhalation [9] or ingestion [10]. At least some nanomaterials can penetrate the skin [11]; even larger microparticles may penetrate skin when it is flexed [12]. Broken skin is an ineffective particle barrier [13], suggesting that acne, eczema, shaving wounds or severe sunburn may enable skin uptake of nanomaterials more readily. Once in the blood stream, nanomaterials can be transported around the body and are taken up by organs and tissues including the brain, heart, liver, kidneys, spleen, bone marrow and nervous system [14]. Nanomaterials have proved toxic to human tissue and cell cultures, resulting in increased oxidative stress, inflammatory cytokine production and cell death [15]. Unlike larger particles, nanomaterials may be taken up by cell mitochondria [16] and the cell nucleus [17], [18]. Studies demonstrate the potential for nanomaterials to cause DNA mutation [19] and induce major structural damage to mitochondria, even resulting in cell death [20], [21].

Size is therefore a key factor in determining the potential toxicity of a particle. However it is not the only important factor. Other properties of nanomaterials that influence toxicity include: chemical composition, shape, surface structure, surface charge, aggregation and solubility [22], and the presence or absence of functional groups of other chemicals [23]. The large number of variables influencing toxicity means that it is difficult to generalise about health risks associated with exposure to nanomaterials – each new nanomaterial must be assessed individually and all material properties must be taken into account.

In its seminal 2004 report Nanoscience and Nanotechnologies: Opportunities and Uncertainties, the United Kingdom's Royal Society recommended that nanomaterials be regulated as new chemicals, that research laboratories and factories treat nanomaterials "as if they were hazardous", that release of nanomaterials into the environment be avoided as far as possible, and that products containing nanomaterials be subject to new safety testing requirements prior to their commercial release. Yet regulations world-wide still fail to distinguish between materials in their nanoscale and bulk form. This means that nanomaterials remain effectively unregulated; there is no regulatory requirement for nanomaterials to face new health and safety testing or environmental impact assessment prior to their use in commercial products, if these materials have already been approved in bulk form.

The health risks of nanomaterials are of particular concern for workers who may face occupational exposure to nanomaterials at higher levels, and on a more routine basis, than the general public.

Although there has been much hype about the potential applications of nanotechnology, most current commercialized applications are limited to the use of "first generation" passive nanomaterials. These include titanium dioxide nanoparticles in sunscreen, cosmetics and some food products; silver nanoparticles in food packaging, clothing, disinfectants and household appliances; zinc oxide nanoparticles in sunscreens and cosmetics, surface coatings, paints and outdoor furniture varnishes; and cerium oxide nanoparticles as a fuel catalyst. The Woodrow Wilson Center for International Scholars' Project on Emerging Nanotechnologies hosts an inventory of consumer products which now contain nanomaterials.

However further applications which require actual manipulation or arrangement of nanoscale components await further research. Though technologies currently branded with the term 'nano' are sometimes little related to and fall far short of the most ambitious and transformative technological goals of the sort in molecular manufacturing proposals, the term still connotes such ideas. Thus there may be a danger that a "nano bubble" will form, or is forming already, from the use of the term by scientists and entrepreneurs to garner funding, regardless of interest in the transformative possibilities of more ambitious and far-sighted work.

The National Science Foundation (a major source of funding for nanotechnology in the United States) funded researcher David Berube to study the field of nanotechnology. His findings are published in the monograph “Nano-Hype: The Truth Behind the Nanotechnology Buzz". This published study (with a foreword by Mihail Roco, head of the NNI) concludes that much of what is sold as “nanotechnology” is in fact a recasting of straightforward materials science, which is leading to a “nanotech industry built solely on selling nanotubes, nanowires, and the like” which will “end up with a few suppliers selling low margin products in huge volumes."

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Summary

As nanotechnology is a very broad term, there are many disparate but sometimes overlapping subfields that could fall under its umbrella. The following avenues of research could be considered subfields of nanotechnology. Note that these categories are fairly nebulous and a single subfield may overlap many of them, especially as the field of nanotechnology continues to mature.