new stem cell approach for blindness successful in mice ( w / video ) cells which have re - formed the light sensitive layer of the retina are shown in green. ( medical xpress ) — blind mice can see again, after oxford university researchers transplanted developing cells into their eyes and found they could re - form the entire light - sensitive layer of the retina. videos show the nocturnal mice, which once didn ' t notice the difference between light and dark at all, now run from the light and prefer to be in the dark – just like mice with normal vision. the researchers say the approach has relevance for treating patients with retinitis pigmentosa, a condition in which the light - sensing cells in the retina gradually die leading to progressive blindness. the study was led by professor robert maclaren in the nuffield department of clinical neurosciences at the university of oxford, together with dr mandeep singh, an eye surgeon from the national university hospital of singapore who is currently undertaking phd studies in oxford. the findings are published online in the journal pnas. the researchers worked with mice that are blind due to complete loss of the light - sensing photoreceptor cells in their retinas. this is the most relevant mouse model for treating patients who are blind from retinitis pigmentosa. this video is not supported by your browser at this time. after two weeks, the researchers showed the cells transplanted into the eye had re - formed a full light - detecting layer on the retina and the mice could see. the cells used were mouse ' precursor ' cells that are on an initial path towards developing into retinal cells. a pupil constriction test showed that, of the 12 mice that received the cell transplant, 10 showed improved pupil constriction in response to light. this shows that the retinas of the mice were sensing the light once more, and this was being transmitted down the optic nerve to the brain. dr singh says : ' we found that if enough cells are transplanted together, they not only become light sensing but they also regenerate the connections required for meaningful vision. ' professor maclaren explains : ' stem cells have been trialled in patients to replace the pigmented lining of the retina, but this new research shows that the light - sensing layer might also be replaced in a similar way. the light - sensing cells have a highly complex structure and we observed that they can resume function as a layer and restore connections after transplantation into the completely blind retina


research shows that the light - sensing layer might also be replaced in a similar way. the light - sensing cells have a highly complex structure and we observed that they can resume function as a layer and restore connections after transplantation into the completely blind retina. ' in looking forward towards potential cell treatments for blindness in humans, professor maclaren explains that they would like to use induced pluripotent stem cells, or ips cells. these are stem cells that have been generated from the patient ' s own cells, such as skin or blood cells, and can then be directed to form precursors of the retina cells. professor maclaren says that this has been achieved by others : ' all the steps are there for doing this in patients in the future. ' the next step is to find a reliable source of cells in patients that can provide the stem cells for use in such transplants, he says. while these are more long - term developments to work towards, professor maclaren says ' our study shows what we could achieve with a cell - based approach. ' ' we have shown the transplanted cells survive, they become light - sensitive, and they connect and reform the wiring to the rest of the retina to restore vision, ' he says. ' the ability to reconstruct the entire light sensitive layer of the retina using cell transplantation is the ultimate goal of the stem cell treatments for blindness we are all working towards. ' more information : www. pnas. org / conte … 110. abstract journal reference : proceedings of the national academy of sciences provided by oxford university - stem cells improve visual function in blind mice oct 01, 2012 | not rated yet | 0 - photoreceptor transplant restores vision in mice apr 18, 2012 | not rated yet | 0 - pig stem cell transplants : the key to future research into retina treatment apr 13, 2011 | not rated yet | 0 - sections of retinas regenerated and visual function increased with stem cells from skin may 16, 2011 | not rated yet | 0 - gene therapy restores vision to mice with retinal degeneration oct 16, 2008 | not rated yet | 0 - motion perception revisited : high phi effect challenges established motion perception assumptions apr 23, 2013 | 3 / 5 ( 2 ) | 2 - anything you can do i can do better : neuromolecular foundations of the superiority illusion ( update ) apr 02, 2013 | 4. 5 / 5 ( 11 ) | 5 - the visual system as


/ 5 ( 2 ) | 2 - anything you can do i can do better : neuromolecular foundations of the superiority illusion ( update ) apr 02, 2013 | 4. 5 / 5 ( 11 ) | 5 - the visual system as economist : neural resource allocation in visual adaptation mar 30, 2013 | 5 / 5 ( 2 ) | 9 - separate lives : neuronal and organismal lifespans decoupled mar 27, 2013 | 4. 9 / 5 ( 8 ) | 0 - sizing things up : the evolutionary neurobiology of scale invariance feb 28, 2013 | 4. 8 / 5 ( 10 ) | 14 is this plasma ( picture in thread ) 1 hour ago http : / / postimg. org / image / d530nwobf / basic physics understanding. could someone explain? 3 hours ago i ' m trying to get a grip on some classic physics by watching a stanford lecture. i ' ve made it through the first one, and now in the second one all... change in flux of a transformer 3 hours ago hello, as i understand, a simple transformer works by using the input ac in the primary coil to generate magnetic field in the iron core, which... electric field between parallel plate capacitor 4 hours ago if you have an infinite non - conducting plate, the electric field just outside is equal to sigma / 2 * epsilon. the electric field just outside a... why angle of projectile has 2 solutions? 5 hours ago i have the final answer of : sin2 ( theta ) = 0. 871 why does ( theta ) = 30. 3 deg or ( theta ) = 59. 7 deg i get why this could be physically, but... how much negative charge do i accumulate by touching the earth? 6 hours ago the earth carries a negative electric charge of roughly 500 thousand coulombs ( according to different sources i ' ve seen ). if i touch the earth i... - more from physics forums - classical physics more news stories ( healthday ) — glucosamine supplements that millions of americans take to help treat hip and knee osteoarthritis may have an unexpected side effect : they may increase risk for developing glaucoma, a small... ophthalmology 23 hours ago | not rated yet | 0 prostaglandin analogues ( pgas ), drugs which lower intraocular pressure, are often the first line of treatment for people with


short stature is a height that is smaller than the average height for a person ' s age, sex, and racial group. it is specifically height that is in the third percentile. short stature is generally broken down into three subgroups :. - familial short stature — parents are short - constitutional delay and development — child is small for age but growing at normal rate, will reach an adult height similar to parents - caused by chronic disease — such as malnutrition, genetic disorders, heart problems, or growth hormone deficiency are just a few that can affect growth treatment will be needed to reach full height potential contact a doctor if you notice a significant decrease in your child ' s growth rate or if your child has stopped growing. familial and constitutional delay are due to the child ' s genetic make - up. if both parents are shorter than average, the child will most likely have short stature. the child may also have delayed puberty. this may cause temporary short stature, but normal height will eventually be reached. medical conditions that may contribute to short stature, include : - malnourishment — most common cause of growth failure and is generally associated with poverty - genetic disorders such as skeletal dysplasias, turner syndrome, down ’ s syndrome, silver russell syndrome - endocrine disorders such as hypothyroidism or growth hormone deficiency - congenital heart disease - kidney diseases - liver failure - sickle cell anemia — a blood disorder - disorders of the stomach or intestines such as inflammatory bowel disease - lung conditions such as cystic fibrosis, severe asthma, chronic obstructive pulmonary disease - use of ssri ’ s medications ( may be used to treat attention deficit disorder or obsesive compulsive disorder ) factors that may increase the risk of short stature include : - having family members with short stature - poor diet - certain diseases and drugs taken by a pregnant woman will increase risk to the newborn child symptoms vary depending on the type of condition. children with familial short stature do not have any disease - related symptoms. they will often reach a height similar to that of their parents. children who have delayed puberty, late bloomers, will often have a close relative with the same delay. these children will also eventually catch up to their peers in height. symptoms that may indicate a medical condition include : - stopped or dramatically slowed growth ( below the third percentile as determined by your doctor ) - weight loss or gain ( more than five pounds in


children will also eventually catch up to their peers in height. symptoms that may indicate a medical condition include : - stopped or dramatically slowed growth ( below the third percentile as determined by your doctor ) - weight loss or gain ( more than five pounds in a month ) - poor nutrition - loss of appetite - chronic abdominal pain and diarrhea - persistent fever - chronic headaches and / or vomiting - delayed puberty ( no spotting by age 15 for a girl or no enlargement of the testes by age 14 - 15 for a boy ) - obstructed sleep apnea your child ’ s doctor will ask about symptoms and medical history. a physical exam will be done. your child ' s height, weight, and body proportion will be measured. the skull and facial features will also be examined. some tests may be done to diagnose or exclude contributing conditions. these tests may include : - bone age : an x - ray to determine the chronological age of your child ’ s bones - to check for hypothyroidism – low levels of thyroid hormone - to check growth hormone levels – an important factor in growth - to check for signs of conditions that may cause short stature like respiratory problems, malnutrition, and liver disease - a complete blood count to check for blood diseases - a genetic exam to detect chromosomal abnormalities and to exclude turner syndrome ( a common cause of short stature in girls ) - urinalysis — examination of urine to look for conditions like kidney disease children with familial short stature do not require treatment. for others, treatment will focus on the cause of short stature. treatments can vary greatly but may include medication or nutritional changes. medication that may be used to treat associated conditions include : - thyroid hormone replacement therapy — may be used in children with hypothyroidism - growth hormone replacement — may be used in children with growth hormone deficiency, prader willi syndrome, or turner syndrome if a medication is associated with short stature your doctor may stop the medication. make sure to talk to your doctor before stopping any medication. malnutrition can contribute to short stature. it may be due to a lack of proper food or other conditions like gastrointestinal problems. in either case, a change in diet may help. talk to your doctor or dietitian to help make effective changes to your child ' s diet. short stature cannot be prevented in children who have a familial short stature or those who have a chronic disease. in some cases, you


butterfly wing scale digital image gallery false acraea butterfly the brilliant orange, red and black patterns of the false acraea butterfly mimic those of other species in order to provide protection from predators, yet, cannot protect them from man. the species ranges from the republic of cameroon and gabon, east across central africa through the congo, and into western uganda. however, the habitat of the false acraea has greatly suffered from many years of war and the local butterfly populations may be shrinking. false acraea butterflies are scientifically described as pseudacraea clarki and are members of the family nymphalidae. the adults have a highly modified front pair of legs, which are no longer utilized for walking. rather, the brush - like legs act as sensory organs used to taste plants as potential egg hosts and larval food sources. sexual dimorphism is highly pronounced in the false acraea species. the males display burnt oranges and reds, but the larger females are more golden and are highlighted by numerous black spots. entymologists are not certain whether the mimicry displayed by the false acraea butterfly is batesian or mullerian. batesian mimicry, in which one species is harmful and the other is harmless, is named for henry walter bates, an english biologist who studied tropical butterflies in the 1850 ' s. mullerian mimicry, named for fritz muller, a german zoologist who worked in the amazon about thirty years after bates, refers to several unpalatable species that share a similar warning pattern. the feeding habits of false acraea caterpillars have often caused them to be regarded as agricultural pests. the larvae feed on several different host plants, such as star apples, red - milkwoods, satin leaf, golden leaf, balata, and bully trees. the fruit of the balata and star apple trees are sold commercially in africa. since the caterpillars are herbivores of the economically important fruit trees, they are often treated with toxic insecticides. additional problems for the species include over - collecting, destruction of habitat due to agricultural conversion of forests, and the aftermath of many years of war. false acraea swallowtail butterfly images in brightfield illumination fur on wing - this high magnification brightfield image features an area of a false acraea wing that is largely devoid of scales. instead, straight pin - like fur is the dominant feature. wing scales and membrane - in the lower right hand corner of this photomicrograph several tapered


the great “ what if ” : jfk and the withdrawal of troops from vietnam see also marc selverstone ' s op - ed in the boston globe on march 9, 2006, available here. arguably, the most vexing of all the great questions of the vietnam era is : “ what if ” president john f. kennedy had not been cut down by an assassin ' s bullet and had lived out his term - - and perhaps a subsequent one - - as president of the united states? would he have made good on an expressed desire to withdraw america troops from vietnam and turn the fighting over to the south vietnamese? these questions are hardly academic ; as a recent op - ed in the new york times by theodore sorensen and arthur schlesinger jr. put it, their one - time boss, president kennedy, had devised a coordinated exit strategy that america ' s current president would do well to emulate. thanks to an extraordinary collection of documents - - the secret tape recordings that president kennedy made during his time in the white house - - we have some sense of what kennedy did - - and didn ' t - - plan to do with respect to vietnam. although available to the public for over a decade, these tapes remain largely unexplored. this is due partly to the many challenges of the transcription process, including the identification of numerous and hard - to - hear voices, the placement of microphones relative to kennedy and his aides, and the quality of the audio itself. yet several key tapes are largely intelligible and reveal the outlines of what is clearly a withdrawal plan, laid out by secretary of defense robert s. mcnamara and chairman of the joint chiefs maxwell d. taylor, in a series of recorded meetings from october 1963. as conceived, the plan would have removed most u. s. troops from vietnam by the end of 1964 and virtually all of them by 1965. to kick - start that process, the defense department was prepared to recall 1, 000 soldiers by the end of 1963. you can listen to some of the related clips below. press the “ listen ” button at the bottom right of the multimedia clip. - jfk on withdrawing 1, 000 troops from vietnam i - jfk on withdrawing 1, 000 troops from vietnam ii - jfk on withdrawing 1, 000 troops from vietnam iii - more clips and exhibits related to the vietnam conflict are available here.


| baldwin, james ( 1924 - 1987 ) | commissioned by harper ’ s magazine to write on the civil rights movement, baldwin first became acquainted with martin luther king during a trip through the south in 1957. baldwin ’ s exposure to king and southern racism had a profound influence on his writing and helped deepen his lifelong commitment to social justice. in a 1960 letter to king baldwin wrote : ‘ ‘ i am one of the millions, to be found all over the world but more especially here, in this sorely troubled country, who thank god for you ’ ’ ( papers 5 : 461 ). the oldest of nine children, james baldwin was born on 2 august 1924. at a young age, baldwin showed promise as an exceptional orator and writer, and at age 14 he became a child preacher at harlem ’ s fireside pentecostal assembly, only to reject the ministry three years later. in 1942 he graduated from the politically progressive de witt clinton high school in the bronx, marking the end of his formal education. after the 1961 publication of baldwin ’ s nobody knows my name, a collection of essays exploring race relations in the united states, king wrote the author, offering the following words of appreciation : ‘ ‘ your analysis of the problem is always creative and penetrating. your honesty and courage in telling the truth to white americans, even if it hurts, is most impressive ’ ’ ( king, 26 september 1961 ). although sometimes critical of king ’ s nonviolent methods, baldwin remained an influential voice for civil rights reform. baldwin attended the 1963 march on washington, and his most powerful collection of essays, the fire next time, which predicted a dangerous race war if relations did not improve in the united states, was published following the march. in december 1987 james baldwin died of stomach cancer in his home in southern france. baldwin, ‘ ‘ the dangerous road before martin luther king, ’ ’ harper ’ s magazine ( february 1961 ) : 33 – 42. baldwin, the fire next time, 1963. baldwin to king, 26 may 1960, in papers 5 : 460 – 461. king to baldwin, 26 september 1961, mlkp - mbu. weatherby, james baldwin, 1989.


the influence of sherlock holmes ( and john watson ) from a fan ’ s perspective the way sherlock holmes is personified ( in books, movies, and television series ), it seems so that no piece of writing will do him any justice. and yet, somehow, he finds doctor john watson, who captures his life and his work perfectly, or as close to perfect as one can get to capturing the likeness of sherlock holmes. sir arthur conan doyle would have never anticipated the sheer amount of impact that his stories have made. the tale of holmes and watson is one that will be told over and over again, passed down from generation to generation through worn, well - loved volumes and books, or through the form of bedtime stories from parent to child. the canon and the fandom ever since the publication of sir arthur conan doyle ’ s most well - known work, there have been fans who hanged on every word ever written about the detective and yearned for more. and “ more ” they got. the fans and followers of sherlock holmes evolved and grew alongside technology and media. in fact, sherlock holmes is the most portrayed movie character, as listed in the guinness book of world records. but, before there was the silver screen and before there was television, there were plays. not only did these plays portray sherlock holmes in the flesh for the fans to enjoy, the plays also acted as a cornerstone for holmesian movies and television series to come. it was ( and still is ) fans and devoted followers of sir arthur conan doyle that has made these adaptations of sherlock holmes possible. the fandom, or fan - base, of sherlock holmes is enormous, as the existence of holmes fans extends from 1887, when the first novel was published, to present day. fandom, when defined by the online etymology dictionary, derives from the word fan and the suffix – dom, and means “ the realm of avid enthusiasts. ” the fandom includes any input to the original canon that is produced by fans : artwork, fiction, plays, ideas, quotes, architecture, and so on and so forth. the fandom derives so much from its canon, or the works of an author that has been authenticated. in this case, the canon of sherlock holmes is all four novels and fifty - six short stories that has been written by sir arthur conan doyle. at the same time, the fandom has put in an incredible amount of contribution into the world of sherlock holmes. the depiction of sherlock holmes as a tall man with a coat, a pipe, and a deersta


written by sir arthur conan doyle. at the same time, the fandom has put in an incredible amount of contribution into the world of sherlock holmes. the depiction of sherlock holmes as a tall man with a coat, a pipe, and a deerstalker was illustrated by a fan. sherlock holmes, when written by sir arthur conan doyle, had never said, “ elementary, my dear watson, ” but the fandom has accepted this as a quote from our beloved detective. “ holmesian ” is a word coined up by the fandom, meaning “ relating to the stories of sherlock holmes. ” there are also holmesian studies in certain universities and colleges, as well as holmesian architecture. this word can also mean a devoted sherlock fan, and is interchangeable with “ sherlockian ; ” although, the latter term is mostly used by american sherlock holmes fan, as well as the fandom of bbc ’ s sherlock. movements have also been spurred by the sherlock holmes fandom, both in victorian and present times. when “ his last bow ” was published in 1893, readers were devastated to learn that the world ’ s only consulting detective had been killed off by sir arthur conan doyle. to mourn the death of sherlock holmes, men and women, respectively, wore black armbands and veils. this reaction was so great that the creator of sherlock holmes had to bring back the well - loved detective, which he had not at all intended to do. similarly, after the finale of the second season of bbc ’ s sherlock was aired, the believe in sherlock ( # believeinsherlock ) movement began. “ i believe in sherlock ” and “ moriarty was real ” are being written everywhere and numerous creative artworks are being created to show support for sherlock holmes. the actions of devoted fans of sherlock holmes show how much the stories and characters mean to them, so much so that said stories and characters have evolved into something more and found a place in culture today, the past, and, quite possibly, the future. | < prev | | next > |


by beverly bell, alexis erkert, and deepa panchang may 23, 2013 over the past few weeks in this article series, we ’ ve heard firsthand from haitian garment workers about low wages, sexual abuse, labor rights violations, and work - related injuries they suffered in sweatshops. meanwhile, the world has watched the death toll in last month ’ s factory collapse in bangladesh creep to above 1, 100. global activists have joined the calls of protesting workers, ramping up pressure on clothing retailers against the regular mistreatment and deaths of workers. slowly, the public is realizing that exploitation within the garment assembly industry is not the exception, it ’ s the rule. today, we take a deep dive into the economics of this sector in haiti to look at how it has come to be, and at what alternative pathways might look like. haiti presidential palace in discussions among foreigners about working conditions and wages in the assembly industry, we often hear, “ but haitians need jobs. wouldn ’ t things be worse without them? ” the question creates a false choice between no job and a grinding, exploitative job. looking at the factors that led to low factory wages in the first place helps expose the myth. western governments and their international financial institution ( ifi ) partners have played an active role in creating the dearth of options that exists for haitian workers. for example, trade policies from the 1980s onward caused the decimation of the haitian agricultural sector. out - of - work farmers fled on masse to cities, and many had no better option but a factory job. foreign policies imposed on the haitian government have also contributed to a near - complete lack of public services and a weak, dependent domestic economy, which ramp up desperation ; desperation, in turn, forced workers to accept the low wages. the offshore assembly model creates a race to the bottom. in it, businesses circle the globe seeking the lowest cost of production – which involves the lowest health and safety standards and suppressed union organizing. as factories move to the next country, they create dirt - poor workers. despite this, governments, the un, and the ifis tout the garment assembly industry as a path to development in global south countries. the un places the expansion of free trade zones ( groupings of export - producing factories that enjoy tax exemptions and fewer safety, health, and environment regulations ) toward the center of its development road map for haiti. a 2009 report it commissioned argued that haiti ’ s duty - free, quota - free preferential access to the american


factories that enjoy tax exemptions and fewer safety, health, and environment regulations ) toward the center of its development road map for haiti. a 2009 report it commissioned argued that haiti ’ s duty - free, quota - free preferential access to the american market, combined with low labor costs and a lack of protectionist policies, makes the country “ the world ’ s safest production location for garments. ” weeks after the earthquake, that paper ’ s author, oxford university economics professor paul collier, likened the catastrophic moment to 19th century development of the us west, with its “ investment booms, financed by enthusiastic outsiders. the earthquake could usher in such a boom in haiti. ” apparently sharing this view, four months after the earthquake the us congress extended us trade preferences for assembled garments to haiti in a law that was portrayed as a relief measure. also since the earthquake, the us and other global players came up with $ 224 million to subsidize the development of a new free trade zone in northern haiti, caracol. developers, who displaced 366 farmers from arable farmland for the project, promised more than 20, 000 jobs. in actuality, fewer than 1, 500 people are employed in the park ; and after paying for transportation and meals, workers reportedly end each day with an average of us $ 1. 36. more free - trade zones are in the offing. for all the funding and attention the sector has received, the 24 factories currently making garments for export to the us employ very few people : 25, 924, or approximately 0. 5 % of the working - age population. no matter the numbers, the industry ’ s contribution to the national economy is false development, said economist camille chalmers with the platform to advocate alternative development in haiti. “ almost all of the primary materials used in manufacturing come from outside. when they say that haiti exports hundreds of millions of dollars in products, a lot of that goes to [ foreign companies to ] pay for the inputs like cloth and equipment. once assembled, the goods aren ’ t consumed in haiti but are shipped abroad. the government doesn ’ t even benefit from taxes or tariffs. haiti ’ s only role is as a stopover in the production process, where cheap labor keeps profit margins high. ” haiti does need work opportunities, as any cash - desperate person there will tell you. but not at any price or under any conditions. former factory worker ghislene delone said, “ it can ’ t be based on the exploitation of people. we need to be treated like


to start, let us recall the basics of the power of two choices, or multiple - choice hashing. in the standard setting, we are hashing n elements into a hash table with n buckets. normally, we would hash each item once to determine its bucket ; this gives a maximum load, or largest number of elements in any bucket, of about log n / log log n. ( all the results i state hold with high probability, so i ' ll avoid repeating the phrase. ) suppose instead we use two hash functions, giving two choices of locations for each element. elements are sequentially placed in the least loaded of their two buckets. when we do a lookup, we ' ll now have to look in two places for the item. in return, the maximum load now falls to about log log n / log 2 - - we ' ve got an extra log in there! ( with d > 2 choices, the maximum load would be log log n / log d, just a constant factor better than d = 2. ) results of this type are due to azar, broder, karlin, and upfal, in their paper balanced allocations. ( there was some earlier work with a similar result by karp, luby, and meyer auf der heide. ) in the course of these results, the question arose as to whether one could do better if placing the elements offline. that is, if you had all n elements and their hashes in advance, could you place each element in one of their bucket choices and achieve a better load than the o ( log log n ) obtained by the sequential placement? the answer turns out to be yes. the best placement only has a constant maximum load. another way to think of this is to say that if we place the elements sequentially, but retain the power to move them later, as long as each element ends up at one of its bucket choices, we could get down to constant maximum load. the idea of cuckoo hashing is that such movements can actually be done online quite efficiently. cuckoo hashing is, essentially, multiple - choice hashing plus moves, and it appears very effective. let us consider an extreme case, analyzed in the original cuckoo hashing paper by pagh and rodler. ( if my description is unsatisfactory, there is a good explanation already on wikipedia! ) each bucket can contain just 1 item, and we will have n buckets, split into two subtables of size n / 2. each


. ( if my description is unsatisfactory, there is a good explanation already on wikipedia! ) each bucket can contain just 1 item, and we will have n buckets, split into two subtables of size n / 2. each element has one choice of bucket in each subtable, where the choices are given by independent hash functions. each hashed element resides at one of its two choices. a lookup therefore always requires at most two accesses into the hash table. what to do, however, on an insertion - - what if both spaces for an item are already full? when we insert a new item, we put it in the first subtable. if another item is already there, we kick it out, and make it move to the second subtable. if another item is already there, we kick it out, and make it move back to the first table, and so on. this is where the name cuckoo hashing comes from ; as the wikipedia article says, the name derives from the behavior of some species of cuckoo, where the mother bird pushes eggs out of another bird ' s nest to lay her own. pagh and rodler prove that if the number of elements inserted is at most ( 1 / 2 - epsilon ) n for some constant epsilon, then this process finishes in constant expected time! in other words, one can achieve memory utilization of up to 50 percent of capacity, with guaranteed constant lookup time and average constant insertion time. further variants significantly improve the memory utilization that can be achieved. specifically, allowing more than two choices of location helps ( more choices of where to go ), as does having more than one item per bucket ( more choices of what to move ). memory utilization of over 90 percent is easily possible in practice. this paper and this one have more information. that summarizes the theoretical background, and hopefully convinces you that the idea of cuckoo hashing is a good one. in the next post, we ' ll look at why you might want to implement cuckoo hashing in hardware, and what obstacles lie therein.


recent " the sky is falling " news stories have dealt with the fall from orbit of the mir space station rather than neo impacts. the press and public are clearly interested in the risk of falling objects, but sometimes risks are perceived in ways that are quite different from the hazard as calculated numerically. the following is a very rough estimate of risks, in " order of magnitude " terms only. it is intended to be illustrative, but certainly not precise. by risk i mean the chance or probability that any individual will be killed as a result of either a spacecraft atmospheric entry or the impact of a neo. let ' s start with the risk of death as a result of being struck by a piece of mir on the assumption that the fragments could land anywhere on earth. suppose 1000 large metal fragments survive to hit the ground, and that if you are within 1 meter of the impact point you will be killed. thus 1000 square meters are at risk, out of a total surface area of the earth of about 100 trillion ( 10 * * 14 ) square meters ( not counting the polar regions ). this is one part in 100 billion of the earth ' s surface, and that is the risk to each individual. multiplying by the earth ' s population of 6 billion, we get a chance of about 1 in 20 that one person on earth would be killed. in fact, the mir atmospheric entry was far from random. it was steered to an impact point in the mid - pacific ocean. unless you lived in that part of the world, the risk to you was zero ( not allowing for an uncertainty in how well this controlled entry would be executed ). since the total population of the pacific is only a few million, the chance that someone would be killed was less than 1 in 20, 000. the folks who sold the russians a $ 200 million insurance policy were very unlikely to have to pay off any claims. for comparison, consider the annual risk of dying as a result of an neo collision with the earth. a number of studies ( e. g., the paper that clark chapman and i published in nature in 1994 ) have shown that this risk is dominated by near earth asteroids of about 2 km diameter. there is a roughly 1 in a million chance of such an impact each year, with estimated death of 1 - 2 billion people. thus the annual risk to each of us of from neo impacts is about 1 in a few million, or more than 10, 000 times greater than the risk from an uncontrolled mir entry. ( note


death of 1 - 2 billion people. thus the annual risk to each of us of from neo impacts is about 1 in a few million, or more than 10, 000 times greater than the risk from an uncontrolled mir entry. ( note : this is a conservative estimate ; many would argue for a neo - impact risk that is higher by an order of magnitude. ) we see from these simple calculations that the risk ( per year ) to each of us from asteroid impact is thousands of times greater than from an uncontrolled mir entry, and millions of times greater than from a controlled mir dive into the pacific. yet no one is taking out insurance policies to protect from cosmic impacts, and this risk receives less news coverage than the demise of mir. why the disparity? for one thing, the death of mir was a known event that provided a good story, while we have no specific prediction of any neo impact. for another, mir was a human - built object over which we had some control ( and responsibility ), while an neo impact is considered an " act of god ". but i suspect that the difference also reflects the fact that very few reporters tried to make a quantitative comparison of these risks. if they had, the results might have surprised them!


aug 1, 2006 nanoetching makes leds brighter researchers in the us claim to have made a resonant cavity led ( rcled ) seven times brighter over a 130 nm bandwidth by etching circular bragg gratings into the device structure ( applied physics letters 89 033105 ). the technique could have applications in displays as well as medical imaging - in particular, say the researchers, optical coherence tomography ( oct ). " we have demonstrated a 7. 5x enhancement of light extraction from a rcled, which in turn has an enhancement factor of 2. 7x over a conventional led, " mark su, lead author of the paper, told optics. org. " whereas only around 2 % of the light generated within a conventional led can be collected, we estimate that we harvested 41 % of the light generated within the led. " a resonant cavity is a way to improve the light extraction of a regular led by placing a mirror below the active layer. however, even in this configuration, most of the emitted light is waveguided below the semiconductor surface and lost. " we used a cavity defined by a circular bragg grating to diffract the guided waves into waves which can be extracted - resulting in the improved light extraction, " explained su. the team, based at the national institute for standards and technology ( nist ), made an infrared - emitting led composed of gallium arsenide packed with quantum dots of indium gallium arsenide. the grating was etched by electron - beam lithography. according to the researchers, the technique is immediately applicable to infrared leds and could have applications in areas such as biomedical imaging ; in particular, oct that requires bright sources with a wide bandwidth. " present - day broadband oct sources have many undesirable properties, such as cost, bulkiness, and problems with the shape of the spectrum they output. so there is room for improvement, " said su. the team believes that nanophotonic structures could also benefit high performance leds for applications such as projectors and displays. " for the visible part of the spectrum, bright leds incorporating design features such as circular bragg gratings could enable energy - efficient projection tvs, or even a new generation of miniature portable projectors, " said su. su adds that the present - day visible sources that could be replaced by led technology are devices like mercury arc lamps and halogen bulbs, which are power - hungry, hot, bulky, burn out and are


january 27, 2012 at 7 : 08 am ( environmental crisis, saving endangered animals + plants, saving oceans / waterways, saving water / waterways, sea life, working together ) tags : africa, antarctica, black pepper, business, faroe islands, fish, mackerel, scottish adjacent waters boundaries order 1999 a school of jack mackerel in the southern pacific. stocks of the fish, rich in oily protein, have declined from 30 million due to a feeding frenzy in the last two decades. jack mackerel, feeds a hungry africa. people eat it unaware of the shortage of this staple fish ; much of it is reduced to feed for aquaculture and pigs. it can take more than five kilograms, more than 11 pounds, of jack mackerel to raise a single kilogram of farmed salmon. the world ’ s largest trawlers, after depleting other oceans, now head south toward the edge of antarctica to compete for what is left. industrial fleets bound only by voluntary restraints compete in what amounts to a free - for - all in no man ’ s water at the bottom of the world. from 2006 through 2011, scientists estimate, jack mackerel stocks declined 63 percent. greed knows no bounds until the ocean balance is totally reduced and thousands of species disappear and people starve. excerpts courtesy of nytimes. com http : / / tinyurl. com / 8yfea6u january 17, 2012 at 7 : 18 pm ( ancient animals, saving endangered animals + plants, saving oceans / waterways, saving water / waterways, sea life, working together ) tags : animals in crisis, beauty of nature, saving endangered animals & plants, saving the biodiversity of planet, working together humpback whale shows amazing appreciation after being freed from nets thanks for this great video. it makes my heart sing and my energy rise. for more ways to raise energy visit. thanks great whale conservancy and utube. com january 17, 2012 at 5 : 18 am ( ancient animals, apes, good news, mammals, primates, saving endangered animals + plants ) tags : beauty of nature, endangered / threatened animals, saving endangered animals & plants, saving the biodiversity of planet on the last day of his vacation this man had an encounter with a troop of mountain gorillas in bwindi national park, uganda unlike most will ever have. january 4, 2012 at 11 : 17 pm ( ancient animals, endangered animals and plants, nature ' s wonders, sea life, working together ) tags :


troop of mountain gorillas in bwindi national park, uganda unlike most will ever have. january 4, 2012 at 11 : 17 pm ( ancient animals, endangered animals and plants, nature ' s wonders, sea life, working together ) tags : animal rights, animals in crisis, beauty of nature, canada, canadian government, endangered / threatened animals, european union, good news, harp seal, international fund for animal welfare, russia, saving endangered animals & plants, saving the biodiversity of planet, seal hunting, sheryl fink, working together international fund for animal welfare ( ifaw ) ’ s seal team director, sheryl fink, has just let me know that russia has banned the import and seal pups slaughtered for fashion export of harp seal skins. this is a huge victory as the canadian government estimates that russia receives 90 % of canada ’ s exports of seal skins. ifaw supporters have worked so hard to help us close down the markets for seal products around the world. next goal end to canada ’ s commercial harp seal hunt. mother nature and her seals thanks everyone for their continued support and for saving their skins for them ( the seals ) to wear. for more seal info image courtesy of nc library january 2, 2012 at 6 : 52 pm ( ancient animals, animal cruelity, good news, mammals, saving oceans / waterways, sea life, working together ) tags : imperial japanese navy, my steve irwin, paul watson, sea shepherd, sea shepherd conservation society, united states, whale wars, whaling in japan eco - activists using drones to protect whales in the antarctic seas the japanese whalers are relentless so whale protectors have taken to the air to save hundreds of whales – remote - controlled drone every morning for the past week, a battery - powered drone with a range of 300km ( 190 miles ) has been launched from the mv steve irwin. this ship is trying to frustrate the whalers into leaving their annual japanese whale hunts in the waters off antarctica. “ we first found the japanese fleet when they were 28 nautical miles away, ” said paul watson, founder of the sea shepherd conservation society, an international marine wildlife protection group based in the united states. watson has 88 crew on three ships, two of which are equipped with spotter drones. with these drones steve watson hopes to finally end the japanese hunt and bringing publicity to the cause in whale wars, the discovery channel documentary series that tracks the hunts : “ our goal is to bankrupt them and destroy them economically. now that we can track them, it is getting


watson hopes to finally end the japanese hunt and bringing publicity to the cause in whale wars, the discovery channel documentary series that tracks the hunts : “ our goal is to bankrupt them and destroy them economically. now that we can track them, it is getting easier. ”. for under £500, the drone used by sea shepherd can run for hundreds of hours. it was given to sea shepherd by bayshore recycling, a new jersey - based solid waste recycling company committed to environmental protection. in addition to paying for the drone at an estimated cost of £10, 000, bayshore also paid for pilot training to run the remote control equipment. it is expected that drones will be used much more frequently to protect mother nature ’ s most endangered species on land and sea. “ everyone here at bayshore is thrilled with the sea shepherd ’ s news of not only saving the lives of many whales, but knowing our drone will continue to track the japanese whaling fleet in this chase, ” said elena bagarozza, marketing co - ordinator at bayshore. watson expects drones will be used to patrol environmentally sensitive areas ranging from the galapagos islands to other famed wildlife areas, including south africa ’ s kruger national park by the sea shepherd crew and other environmental groups. it is very durable handling winds up to 40 knots, waterproofed and has multiple security backups so that if it has problems or low battery it automatically returns to base. excerpts courtesy of guardian. co. uk / environment image courtesy of guardian. co. uk / bveiga


our state geography in a snap : interesting places reprinted with permission from the north carolina department of public instruction website. related entries : cape hatteras lighthouse ; currituck beach lighthouse ; lake mattamuskeet ; nc museum of history ; nc museum of natural sciences ; nc places named for governors ; oakdale cemetery ( wilmington, nc ) ; oak island lighthouse ; roadside attractions ; state transportation signs north carolina is the nation ' s variety vacation land, ranking eighth in the nation for visitation. recreational opportunities abound throughout the state. boating, swimming, saltwater fishing, and most other water sports are enjoyed along the north carolina coast. the mountains offer scenic beauty and a variety of activities, including hiking, golfing, whitewater rafting, and skiing. horseback riding, boating, fishing and golfing are popular activities in the piedmont region. north carolina is recognized worldwide for its more than 450 golf courses located throughout the state. recreation areas in north carolina include the great smoky mountain national park, the blue ridge parkway, cape hatteras and cape lookout national forests, and 36 state parks and recreation areas. park facilities include more than 60 public campgrounds. in addition, north carolina has more than 300 private camping facilities. the north carolina zoological park, the nation ' s first state operated national - habitat zoo, is located in asheboro. other attractions include the carowinds theme park and the charlotte motor speedway. some of the state ' s most popular cultural attractions include the north carolina museum of art, the north carolina museum of natural history, the american dance festival, " the lost colony " outdoor drama, the north carolina symphony and the north carolina maritime museum in carteret county. historic sites include the wright brothers national memorial, restored old salem village, the carl sandburg and thomas wolfe homes, tryon palace, biltmore house and gardens, roanoke island, cape hatteras lighthouse, duke university museum of art, and the woolworth ' s building in greensboro, the location where, in 1960, four black students from north carolina a & t university seated themselves at a " whites only " counter. " social studies : : elementary resouces : : student sampler : : geography, " north carolina department of public instruction website. http : / / www. ncpublicschools. org / curriculum / socialstudies / elementary / studentsampler / 20geography # location ( accessed march 27, 2012 ). " hawksbill mountain, north carolina - december 30, 2008 ". photo courtesy of


the formation of counties was one of the first matters attended to by the lords proprietors after they received their charter in 1663 from king charles ii for the vast tract of land in america he called the province of carolina. in 1664 the proprietors formed " all that parte of the province which lyeth on the north east side or starboard side entering of the river chowan now named by us albemarle river together with the islands and isletts within tenn leagues thereof " into a county that they named albemarle county for george monck, the duke of albemarle, himself one of the proprietors. this was the site of the first permanent settlement in carolina. they then divided the new county into four precincts : currituck, perquimans, pasquotank, and chowan. albemarle county was subsequently enlarged, and in 1696 the area south of albemarle sound was removed from albemarle and made into a new county, named bath, which in turn was divided into the precincts of beaufort, hyde, craven and carteret. the primary reason for establishing counties ( or precincts ) was to provide local seats of government where citizens could record documents, such as deeds or wills, and participate in court proceedings. at the same time, the sheriff was provided with a home base from which to fulfill his basic responsibilities of collecting taxes and maintaining law and order. by 1738 albemarle and bath counties had been dissolved and the 14 precincts then in existence became counties, a designation that has remained since the seventeenth century. throughout the remainder of the colonial period, as settlement spread westward and population increased, older counties were divided and new ones formed. with statehood came an even greater rate of growth, and by 1800 the number had risen to 59 counties covering all of the state. in many cases, the dividing of counties caused heated political controversy, as eastern counties were often divided to maintain that region ' s majority in the state legislature against expanding representation from the piedmont and mountain regions. shifts in population continued throughout the nineteenth century and into the twentieth century, resulting in even more counties. larger counties were divided, and those in turn were sometimes divided yet again, until the seemingly magical figure of 100 was reached in 1911. ( for a time, the number of counties was actually greater than 100, but some of these were ceded to tennessee in 1789 and others were absorbed into other counties or never fully developed. ) the number remained at 100, although in 1933 the


1911. ( for a time, the number of counties was actually greater than 100, but some of these were ceded to tennessee in 1789 and others were absorbed into other counties or never fully developed. ) the number remained at 100, although in 1933 the general assembly authorized the consolidation of existing counties subject to approval of the electorate. this could have resulted for the first time in a decrease from the 100 county figure, but as of the early 2000s there had been no such consolidations. initially, county government and judicial matters were in the hands of justices of the peace, who formed a body known as the court of pleas and quarter sessions. the justices were appointed by the governor, with strong input from the members of the colonial assembly from the affected county, leaving the average citizen with no say as to who would run the government of the county in which he lived. at first the court of pleas and quarter sessions met wherever it was convenient to assemble a quorum, usually in a private home. a 1722 act of the assembly instructed the justices to pick a site for a permanent seat of government for each precinct, where they were to buy an acre of land and build a courthouse. whether in the early precinct days, or after the name of the local government entity was changed from precinct to county, the justices had the support of a sheriff for law enforcement, as well as a clerk of court and a register of deeds. of the three, both the clerk of court and the register of deeds needed to remain in their offices in the courthouse, which left only the sheriff free to travel about the county. accordingly, he was also designated tax collector, a position sheriffs continued to hold until the latter part of the twentieth century. the general system of county government of the early colonial period, with the appointed members of the court of pleas and quarter sessions running things, was carried over into statehood, and little changed until the adoption of the north carolina constitution of 1868. the system called for by the new constitution, known as the township and county commissioner plan, gave control of county government to five commissioners, to be elected at large by the county ' s voters. in addition, each county was divided into townships whose residents elected two justices to serve as the township ' s governing body, as well as a three - member school committee and a constable. the new system significantly reduced the general assembly ' s control of county government, since the legislators no longer appointed the justices of the peace who made up the county court. the township and county commissioner plan, patterned after one previously adopted


committee and a constable. the new system significantly reduced the general assembly ' s control of county government, since the legislators no longer appointed the justices of the peace who made up the county court. the township and county commissioner plan, patterned after one previously adopted in pennsylvania, did not prove universally popular in north carolina and lasted less than a decade. at a constitutional convention in 1875, the general assembly was authorized to change the system, and in the session of 1877 townships were reduced to little more than geographic and administrative subdivisions of the counties. this seriously reduced the authority of county commissioners. the modern system of county government, in which an elected board of commissioners is responsible for managing a county ' s affairs, including setting the rate and collecting taxes and determining where funds should be expended, dates to the early twentieth century. periodically after that, the general assembly conferred additional authority and responsibility on the county commissioners, until at the end of the century they had been provided with such a wide range of " home - rule " statutes that many counties found it impossible to run their greatly expanded business without professional help. this led to the adoption by many counties of the county manager plan. under this plan, commissioners employ a county manager to serve as a sort of chief executive of the county business - in some instances, the largest business in the county - with the manager having certain independent authority, including that of hiring and firing employees. as with other matters, the state determines what sources the counties may tap for income. traditionally, the real estate tax has been the primary revenue source for north carolina counties. however, especially in the last half of the twentieth century, counties were able to prevail on the general assembly to let them collect from a variety of other sources, among those favored being local sales taxes, land transfer taxes, meals taxes, and occupancy taxes. a. fleming bell, ed., county government in north carolina ( 3rd ed., 1989 ). david leroy corbitt, the formation of the north carolina counties, 1663 - 1943 ( 1969 ). 1 january 2006 | stick, david


when bo dubose was younger, he spent many a weekend following his father around civil war battle sites in search of artifacts. they were quite good at it, amassing what is believed to be the largest private collection of its kind, which includes more than 7, 500 union and confederate objects. i have heard bo talk about his impressive collection on several occasions, about spending holidays driving from historic site to historic site, his father studying civil war military journals in search of arms caches with remarkable success. their collection has been the backbone of the atlanta history center in buckhead since it opened. we ’ d all love to have bo ’ s skill and good fortune hunting for artifacts, but most of us were equipped only with metal detectors and our imaginations. our backyard off west wesley road in buckhead yielded the occasional buried metal toy or coin, nothing of any historic significance. our grandparents ’ backyard on brighton road in brookwood hills was another story. perhaps my cousins and my brothers were aware, but i did know that land on which our grandparents mary adair and buster bird ’ s house sat was in close proximity to the first strike that began the battle of peachtree creek. confederate soldiers had retreated past peachtree creek when the general of those armies, joseph johnson, was essentially fired for constantly — what else? — retreating. union troops were marching south toward atlanta, constantly trying to outflank the retreating rebels. the confederate brain trust in richmond wanted a change, assigning the more aggressive gen. john hood the task of defending the most important city in the south during the war. the result was inevitable. on july 20, 1864, hood tried to catch the yankees crossing peachtree creek, unaware. an offensive that was supposed to begin at 1 p. m. didn ’ t get under way until closer to 4. those three hours and miscommunications sent the soldiers into the teeth of an army that was prepared to defend itself. the battle raged on from howell mill to brookwood hills along present - day collier road. there was a lot of confusion, and huge losses on the confederate side. there were some minor successes for the rebels, but the union lines essentially held and repelled the attack. atlanta wouldn ’ t fall until sept. 2, 1864, but the battle is seen as the beginning of the end for the confederacy. at the time of the battle, this area was to the north of the city and was densely forested. to see the photos from before and after is to get a sense of the devastating impact of


layer 2 switching - layer 2 switching is hardware based, it uses the host ' s media access control ( mac ) address. - switches use application specific integrated circuits ( asic ) to build and maintain filter tables. - switches tend to be faster than routers, because they don ' t look at the logical address ( network layer headers ), they instead use the hardware address defined at the data link ( mac ) layer to decide whether to forward or discard the frame. - layer 2 switching is so efficient because it doesn ' t modify the data packet only the frame encapsulating the packet ; this also causes it to be less error prone. - uses layer 2 switching for network connectivity and network segmentation ( each port is a separate collision domain ). - be careful how you segment your network, ensure that the users spend 80 % of their time on their local segment, and all the segments of a switch are still in the same broadcast domain. use routers to split up broadcast domains. benefits of lan switches ( layer 2 services ) an individual layer 2 switch might offer some or all of the following benefits : - bandwidth - - - lan switches provide excellent performance for individual users by allocating dedicated bandwidth to each switch port ( for example, each network segment ). this technique is known as microsegmenting. - vlans - - - lan switches can group individual ports into logical switched workgroups called vlans, thereby restricting the broadcast domain to designated vlan member ports. vlans are also known as switched domains and autonomous switching domains. communication between vlans requires a router. - automated packet recognition and translation - - - cisco ' s unique automatic packet recognition and translation ( apart ) technology recognizes and converts a variety of ethernet protocol formats into industry - standard cddi / fddi formats. with no changes needed in either client or server end stations the catalyst solution can provide an easy migration to 100 - mbps server access while preserving the user ' s investment in existing shared 10base - t lans. three functions of layer 2 switching - address learning - layer 2 switches retain, in their filter tables, the source hardware address and port interface it was received on. - forward / filter decisions - when a frame is received, the switch looks at the destination hardware address and finds the interface it is on in the filter table. if the address is unknown, the frame is broadcast on all interfaces except the one it was received on. - loop avoidance - if multiple connections between switches exist for redundancy


destination hardware address and finds the interface it is on in the filter table. if the address is unknown, the frame is broadcast on all interfaces except the one it was received on. - loop avoidance - if multiple connections between switches exist for redundancy, network loops can occur. spanning tree protocol is used to stop loops while still allowing redundancy. spanning tree protocol stp is a layer 2 link management protocol that provides path redundancy while preventing undesirable loops in the network. for an ethernet network to function properly, only one active path must exist at layer 2 between two stations. stp operation is transparent to end stations, which do not detect whether they are connected to a single lan segment or a switched lan of multiple segments. the catalyst series switches use stp ( ieee 802. 1d bridge protocol ) on all ethernet virtual lans ( vlans ). when you create fault - tolerant internetworks, you must have a loop - free path between all nodes in a network. in stp, an algorithm calculates the best loop - free path throughout a catalyst - switched network. the switches send and receive spanning - tree packets at regular intervals ( 2 seconds ). the switches do not forward the packets, but use the packets to identify a loop - free path. the default configuration has stp enabled for all vlans. multiple active paths between stations cause loops in the network. if a loop exists in the network, you might receive duplicate messages. when loops occur, some switches see stations on both sides of the switch. this condition confuses the forwarding algorithm and allows duplicate frames to be forwarded. to provide path redundancy, stp defines a tree that spans all switches in an extended network. stp forces certain redundant data paths into a standby ( blocked ) state. if one network segment in the stp becomes unreachable, or if stp costs change, the spanning - tree algorithm reconfigures the spanning - tree topology and reestablishes the link by activating the standby path. - defined as ieee 802. 1d - it first elects a root bridge ( only 1 per network ), root bridge ports are called designated ports which operate as forwarding - state ports. forwarding - state ports can send and receive traffic. other switches in your network are nonroot bridges. - the nonroot bridge ' s port with the fastest link to the root bridge is called the root port, and it sends and receives traffic. - ports


ports can send and receive traffic. other switches in your network are nonroot bridges. - the nonroot bridge ' s port with the fastest link to the root bridge is called the root port, and it sends and receives traffic. - ports that have the lowest cost to the root bridge are called designated ports. the other ports on the bridge are considered non designated and will not send or receive traffic, ( blocking mode ). - switches or bridges running stp, exchange information with what are called bridge protocol data units ( bpdu ). bpdus send configuration information using multicast frames, bpdus are also used to send the bridge id of each device to other devices. the bridge id is used to determine the root bridge in the network and to determine the root port. the bridge id is 8 bytes long, includes priority and mac address. the default priority of devices using ieee stp is 32, 768 ( 215 ). - to determine the root bridge the priority and the mac addresses are combined, if priority is the same, the mac address is used to determine the who has the lowest id, which determines who will be the root bridge. - path cost is used to determine which ports will be used to communicate with the root bridge ( designated ports ). stp cost is the total accumulated path cost based on the bandwidth of the links. the slower the link the higher the cost. spanning tree protocol port states - blocking - doesn ' t forward any frames, but still listens to bpdus. ports default to blocking when the switch powers on. used to prevent network loops. if a blocked port is to become the designated port, it will first enter listening state to ensure that it won ' t create a loop once it goes into forwarding state. - listening - listens to bpdus to ensure no loops occur on the network before passing data frames. - learning - learns mac addresses and builds filter table, doesn ' t forward frames. - forwarding - sends and receives all data on the bridge ports. a forwarding port has been determined to have the lowest cost to the root bridge. lan switching modes - store and forward - the entire frame is copied into its buffer and computes the cyclic redundancy check ( crc ). since it copies the entire frame, latency varies with frame length. if the frame has a crc error, is too short ( < 64 bytes ), or is too long ( > 1518 bytes ) it is discarded. if no error, the destination address ( mac ) is


a bolivian tribe living between santa cruz de la sierra and cochabamba in the wooded regions and plains adjoining the mountains, on the eastern slopes of the andes, close to the rio beni and rio marmore. they are tall, and the women are very handsome. they have oval countenances, aquiline noses, very dark eyes, while their skin is almost as white as that of the spaniards. the yuracare are excellent hunters and make good warriors ; they were of a roving disposition, but the jesuits of the paraguayan reductions succeeded in establishing a mission among them, which flourished until the suppression of the society. the standard of morality among the yuracare was very low. the marriage bond was readily dissolved, but polygamy was not practised. they were distributed in families, living without any form of government. men and women were separated at meals, but there was no subordination between husband and wife or relatives, though the parents were generally treated as slaves by the children. they were an extremely superstitious race, but they adored neither nature nor a superior being. they believed in the immortality of the soul but had no idea of future rewards or punishments. the dead, who were mourned for a long period, were buried with their bows and arrows, as they were supposed to have gone to a delightful region under the earth, where the woods abounded with peccaries and the hunting never failed. the yuracare live entirely by hunting ; they consider it lawful to commit suicide, and practice duelling, which is carried out according to rules laid down by public authority. they make it a rule never to advise their children, leaving them to form their own standard of conduct. reclus, universal geography ed. keane, xviii ( london, 378 - 9 ). apa citation. ( 1912 ). yuracare indians. in the catholic encyclopedia. new york : robert appleton company. http : / / www. newadvent. org / cathen / 15738c. htm mla citation. " yuracare indians. " the catholic encyclopedia. vol. 15. new york : robert appleton company, 1912. < http : / / www. newadvent. org / cathen / 15738c. htm >. transcription. this article was transcribed for new advent by michael t. barrett. ecclesiastical approbation. nihil obstat. october 1, 1912. remy lafort, s. t. d., censor. imp


their study, " cdk9 / cyclin t1 expression during normal lymphoid differentiation and malignant transformation, " appears in the journal of pathology ( volume 203, issue 4 ). lymphomas are generally difficult to diagnose since no single test currently exists to sufficiently establish their presence. clinical practice often revolves around a pathologist looking for changes in normal lymph node architecture and cell characteristics through a series of tests, such as blood tests, x - rays, computerized tomography ( ct ) scans, magnetic resonance imaging ( mri ) and bone marrow biopsy. " there are many types and subtypes of lymphoma, some of which are easy to detect, but many that are very difficult to identify, " says antonio giordano, m. d., ph. d., director of the sbarro institute at temple and one of the study ' s principal investigators. the researchers found that by taking a sample of blood and doing immunohistochemical analysis for the expression of cdk9 and cyclin t1, they were able to accurately pinpoint the type of lymphoma - - hodgkins or non - hodgkins - - as well as its stage of advancement. non - hodgkins lymphoma is the sixth - most common cancer in the united states. " basically, this new method is a very powerful tool in determining the presence of cancer by analyzing these two molecules in the lymphoid tissue, " explains giordano, an internationally recognized researcher in the genetics of cancer and gene therapy. " the change of levels of cdk9 and cyclin t1 in lymphoid cells shows a correlation with activity of the cancer. t contact : preston m. moretz


new anticancer drugs are usually developed specially for the job, but occasionally they are borrowed from another field of medicine, and applied speculatively in cancer. tamoxifen was designed as an anti - oestrogen, based on the observation that at least a third of breast cancers depend on female sex hormones such as oestrogen for survival. tamoxifen has shown to be an exceptionally effective molecule in cancer treatment ; it was never planned to be a preventive agent, but so it has proved to be! it is now licensed to be used to prevent breast cancer in certain women at high risk of the disease. contrast this with raloxifene, a drug first developed to treat osteoporosis in women. a selective benzothiophene oestrogen receptor modulator ( serm ), raloxifene binds to oestrogen receptors as a mixed oestrogen and anti - oestrogen effect. it functions as an oestrogen sometimes ( in bones and on lipid metabolism ) and as an anti - oestrogen in other target tissues ( endometrium and breast ). so, it has the potential for producing some of oestrogen ' s beneficial effects without producing its adverse effects. in a trial of its use in osteoporosis, it appeared to have another completely different effect, namely prevention of new hormone dependant breast cancers. results from the more ( the multiple outcomes of raloxifene evaluation ) study of 7, 705 women that were randomised to raloxifene or placebo demonstrated that among postmenopausal women with osteoporosis, the risk of invasive breast cancer was decreased by 76 % during three years of treatment with raloxifene. stronger evidence on the safety and efficacy of raloxifene is awaited from the star trial. this trial includes almost 20, 000 postmenopausal women in the us who are at increased risk of breast cancer to determine whether raloxifene is as e contact : ebcc - 5 press office federation of european cancer societies


the documents are in an ultra - high resolution format and reveal details previously invisible to the naked eye. - the ancient text to the dead sea scrolls are now available online. - the scrolls are the oldest known biblical manuscripts in existence. - they are considered by many to be the most significant arhcheological find of the 20th century. five of the main dead sea scrolls, containing some of the oldest - known surviving biblical texts, were put online as part of a joint project between the israel museum and google. the project gives the public access to ultra high - resolution images of the ancient scrolls in a format which is easily searchable, with the magnified text revealing details previously invisible to the naked eye, a museum statement said. so far, five of the scrolls have been digitised as part of the $ 3. 5 - million project which uses space - age technology to produce the clearest renderings yet of the ancient texts : the great isaiah scroll, the community rule scroll, the commentary on habbakuk, the temple scroll and the war scroll. by visiting http : / / dss. collections. imj. org. il / web users can view all of the text, as well as a translation tool and other background information on the documents, the museum said. " we are privileged to house in the israel museum ' s shrine of the book the best preserved and most complete dead sea scrolls ever discovered, " israel museum director james snyder said in a statement, describing them as of " paramount importance " for the world ' s monotheistic religions. " now, through our partnership with google, we are able to bring these treasures to the broadest possible public. " the 900 biblical and other manuscripts, comprising some 30, 000 fragments, were discovered between 1947 and 1956 in the qumran caves above the dead sea and photographed in their entirety with infra - red technology in the 1950s. the parchment and papyrus scrolls contain hebrew, greek and aramaic writing, and include several of the earliest - known texts from the bible, including the oldest surviving copy of the ten commandments. the oldest of the documents dates to the third century bc and the most recent to about 70 ad, when roman troops destroyed the second jewish temple in jerusalem. the artifacts are housed at the israel museum in jerusalem, where the larger pieces are shown at the dimly lit shrine of the book on a rotational basis in order to minimise damage from exposure. when not on show, they are kept in a dark, climate - controlled storeroom in conditions similar to those


some u. s. states are feeling the heat of climate change more than others, finds a new analysis of temperature increases over the past 100 years. the state that saw the highest temperature increase was rhode island, followed by massachusetts, new jersey, arizona and maine. scientists from climate central, a research and public outreach organization, suggest natural climate variability along with atmospheric aerosols ( that block incoming solar radiation ) both play roles in the findings. for each state in the continental u. s., scientists from climate central calculated averages of the daily high and low temperatures from national climatic data center ’ s u. s. historical climatology network of weather stations. then, they determined how much the average daily temperatures changed each decade over the past 100 years. the top 10 fastest - warming states in descending order : - rhode island - new jersey the 10 slowest - warming states : - south carolina - west virginia overall, the scientists found that the pace of warming increased dramatically starting in the 1970s, with every state showing a rise in overall temperatures over the past 40 years. this bump coincides with the time when the effect of greenhouse gases began to overwhelm the other natural and human influences on climate at the global and continental scales, the researchers said. so they split up their data into two groupings : from 1912 to the present and from 1970 to the present. over the past 100 years, the top 10 fastest warming states warmed 60 times faster than the bottom 10 states, or 0. 26 degrees f ( 0. 14 degrees c ) per decade vs. 0. 004 f ( 0. 002 c ) per decade. since 1970, the speed of warming across the lower 48 states more than tripled, increasing from 0. 127 f ( 0. 071 c ) per decade over the 100 - year period to 0. 435 f ( 0. 242 c ) per decade since 1970. the gap between the fastest - and slowest - warming states also shrunk after 1970, with the top 10 states heating up twice as fast as the bottom 10 states. regional trends were also found, with states in the southwest, northeast, upper midwest and northern rockies showing the fastest warming, while states in the southeast and midwest regions tended to warm much slower. this region of slow warming has been termed " the warming hole " by some ; past research showed that aerosol pollutants emitted into the atmosphere over the past 60 years from industrial and power plants in the eastern u. s. would create a cooling pattern similar to this warming hole


by lee crockett the united states has the largest exclusive economic zone ( eez ) in the world, containing 3. 4 million square miles [ 8. 8 million square kilometers ] of ocean and 90, 000 miles [ 145, 000 kilometers ] of coastline. [ i ] throughout this vast underwater realm, fish play an essential role in the interconnected web of life on which we depend. in fact, they are one of america ’ s most valuable natural resources, adding billions to the u. s. economy and supporting millions of jobs through fishing and recreation. unfortunately, overfishing — taking fish from our oceans faster than they can reproduce — has plagued u. s. oceans for decades and continues today. this squanders valuable fish populations and weakens ocean ecosystems, making them more vulnerable to problems like pollution, natural disturbances and climate change. the good news is that we have a strong law in place in the united states governing how fish are managed in federal waters, and serious efforts are underway to end overfishing and rebuild depleted populations. the pew environment group supports these goals through our work at the federal and regional levels of government, where decisions are made about these invaluable marine resources. “ with so much at stake, it ’ s critical that as many americans as possible be actively engaged in this discussion. ” fishermen, conservationists and scientists have actively debated how best to manage our ocean fish populations for decades. but with so much at stake, it ’ s critical that as many americans as possible be actively engaged in this discussion. the “ overfishing 101 ” blog series aims to do just that by providing a new outlet, in which we hope to open up the discussion to the larger public, cut through the rhetoric and encourage more people to participate in marine fish conservation. in coming posts, i will cover the basic state of our nation ’ s ocean fish populations, explore policies that can help safeguard them for future generations and dispel some myths about how current u. s. fisheries policy is made. in addition, the series will feature insights from independent experts and partners working with pew, as well as interactive web content, such as videos and other online resources related to ocean fish and fishing. more about us the federal fisheries policy project leads efforts to ensure that congress and the national marine fisheries service effectively implement the law to end overfishing, rebuild depleted fish populations and protect ocean ecosystems. the campaign works closely with scientists, policy makers, fishery managers, fishermen and conservation organizations throughout the country to promote adequate funding and support current


national marine fisheries service effectively implement the law to end overfishing, rebuild depleted fish populations and protect ocean ecosystems. the campaign works closely with scientists, policy makers, fishery managers, fishermen and conservation organizations throughout the country to promote adequate funding and support current fish conservation mandates. to find out how you can help, go to : www. pewenvironment. org lee crockett joined the pew environment group in june 2007 as director of federal fisheries policy. before that, he was executive director of the marine fish conservation network, the largest national coalition dedicated exclusively to promoting the sustainable management of ocean fish. previously, he was a fishery biologist with the national marine fisheries service, leading agency efforts to protect essential fish habitat. he also served as a staff member of the house committee on merchant marine and fisheries, working on a variety of fisheries, environmental and boating safety issues. crockett holds a bachelor ’ s degree in biology and a master ’ s degree in biological oceanography from the university of connecticut. before college, he served in the u. s. coast guard. this series of posts authored by lee crockett — head of pew environment group federal fisheries policy and a life - long angler — explores the importance of sustainable fisheries management to the u. s. the series marks the 35th anniversary of the passage of america ’ s primary fisheries management law ( magnuson - stevens fishery conservation and management act ) coming up next month ( april 13 ). the views expressed in this post are those of lee crockett and / or pew environment, and not necessarily those of the national geographic society. we welcome other viewpoints and comments, but reserve the right to edit or delete abusive or objectionable content. footnote : [ i ] http : / / coastalmap. marine. usgs. gov / gisdata / basemaps / boundaries / eez / noaa / useez _ noaa. htm


turner to monet nothing happens here, it seems. a field of snow is marked by some trees on the top, a road at the right, clouds, and the intimation of lightening on the horizon. a few vertical scratches indicate grass poking through a crust of snow. but what intensity of observation! the paint wiped around the hill makes the viewer think about the colour white, how it can be made yellow, grey or blue. the trees are nothing but black blobs marking edges, while snow - filled clouds animate the scene, pushed across the sky by winter wind. in his short career, bastien - lepage was famous for naturalistic depictions of peasants, especially girls working in the fields ; robust and alive, their figures dominate the scene. 1 his land was always under cultivation, sowing or harvest. here the landscape is beyond human use, made fallow by the season, by the ruthless power of winter. for bastien - lepage, the fecundity of agriculture represented france recovering its pride and productivity after the disastrous military defeat by prussia in 1870. in this work the small village of damvillers is enshrouded in snow and ice, under a watery sky, but there is a hint of light and hope that prefigures a change of weather and, eventually, of season. because he was neither academician nor impressionist, bastien - lepage has been neglected in the analysis of the culture wars that raged in the nineteenth century between conservatives and radicals. even an apparently subjectless painting like snow effect, damvillers may seem progressive because it lacks detail, finish, incident and preferably a moral, all demanded by the academy. but the artist ’ s observations are not only of the moment, like monet ’ s haystacks, midday. the hill is eternal, not simply created by the light in which it is observed : the effects may be fleeting, but the land remains, permanent and solid, underneath the snow. 1 see, for example, season of october : the potato gatherers 1878 in the collection of the national gallery of vicitoria, melbourne.


having diabetes doesn ' t mean that you have to give up all of the foods you like or buy special ' diabetic ' foods. it just means that you should try to follow a balanced meal plan. why it ' s important to eat healthy with diabetes eating healthy will give you more energy to do all the things you want and need to do in your busy life. if you eat too many carbohydrates or too much rich food, your blood sugar levels can go up quickly. this can make you feel tired or sluggish. following a healthy eating plan helps you manage your blood sugar levels and your weight. salt and cholesterol eating foods high in saturated fat, trans fat or cholesterol can lead to high fat and cholesterol levels. this can cause fat and cholesterol to stick to the insides of blood vessels. when that happens, the blood vessels can become narrowed over time. so avoiding fats helps to lower risk of health complications. the benefits of healthy eating there are many benefits of eating healthy foods : - reaching and staying at a weight that ' s good for your body - keeping your blood sugar and cholesterol under control - preventing heart and blood vessel disease the glycemic index foods with a high glycemic index can spike your blood sugar levels. choosing foods with a low glycemic index raise your glycemic index slower - so you should eat them more often.


the diagram illustrates the formula : 1 + 3 + 5 +... + ( 2n - 1 ) = n² use the diagram to show that any odd number is the difference of two squares. in 15 years ' time my age will be the square of my age 15 years ago. can you work out my age, and when i had other special birthdays? libby jared helped to set up nrich and this is one of her favourite problems. it ' s a problem suitable for a wide age range and best a basic introduction to magic squares can be found here. magic squares have intrigued people for thousands of years and in ancient times they were thought to be connected with the supernatural and hence, magical. today, we might still think of them as being magical, for the sum of each row, column and diagonal is a constant, the magic constant. the squares intrigued me when i found that their construction was far from easy. for the simple 3x3, that is order 3 magic square, trial and improvement quickly does the job ; but for higher than order 4 magic squares a method is necessary. the problem of construction is twofold. an algorithm which works for odd order squares will not work for even order squares without the further addition of another algorithm. at least, i know of no method which will work for both odd and even orders, other than trial and improvement computer programs. for the purposes of this article, i will be considering only magic squares that are constructed using consecutive integers from 1 to n 2, where n is the number of integers on one side of the square. odd magic squares are fairly easily constructed using the either the siamese ( sometimes called de la loubere ' s, or the staircase method ), the lozenge, or the de meziriac ' s methods. the first two methods are described in some detail on the web site : " eric ' s treasure trove of mathematics ' '. either way use " magic squares ' ' in the search engine on that site. de meziriac ' s method can be found on page 76 in the book " mathematical games and puzzles ' ', by trevor rice and published by b. t batsford limited, london. another way, which i prefer ( but then that was the way i learned to construct odd order squares ), is the extended pyramid method or diagonals. this method consists of three steps : the same pyramid method can be used for any odd order magic square as shown below for the 5x5 square in figure 2.


learned to construct odd order squares ), is the extended pyramid method or diagonals. this method consists of three steps : the same pyramid method can be used for any odd order magic square as shown below for the 5x5 square in figure 2. we can use some properties of magic squares to construct more squares from the manufactured squares above ; e. g. this will be the subject of the next article published in september. constructing the even order magic squares does present more of a challenge. there are many different ways, which can be studied through " eric ' s treasure trove of mathematics ' ' ; at least as a starting point. all the methods i have seen in the literature are rather complicated, in that they require the use of two or more algorithms. there are claims for a simple method for the construction of even order magic squares, but i have yet to find such a method. however, the following method, which i have developed, uses but one algorithm and will work for any even sided square. i call it the " paired exchange method ". the theory behind the paired method is fairly straightforward. consider the first and last column of a n x n magic square where n is even. starting by placing the integers in order across the rows of the square ( see figure 3 ), the difference between the first and last number in any row will be n - 1. since there are n rows in the square, there will be a total difference of n ( n - 1 ) between the first and last column of the square. to balance the total for the first and last columns we must exchange pairs of numbers between the first and last columns and each exchanged pair must be from the same row, so as not to change the sum total of the row. how many times must we exchange pairs to equalise the columns? when a pair is exchanged in a row the difference between the columns changes by 2 ( n - 1 ). if t is the number of times pairs must be exchanged, then a similar argument can be made for the 2 nd and the next to last columns, since the only change in the above formulae will be to substitute ( n - 3 ) for ( n - 1 ). the resulting t stays the same. in like manner, all columns paired from the centre line of the square can be made to be equal, and since the numbers in the original square are consecutive integers, all the columns will be equal to the magic constant for the n by n magic square. of course, columns are just rows seen from


line of the square can be made to be equal, and since the numbers in the original square are consecutive integers, all the columns will be equal to the magic constant for the n by n magic square. of course, columns are just rows seen from a different viewpoint, hence in a like manner all rows can be made to equal the magic constant. now let ' s look at a few examples. consider the 4 by 4 magic square. t is now equal to 2. the choice of pairs to exchange is limited if we want the sum of the numbers on the diagonals to equal the magic constant. the pairs must be on the diagonals. by reflecting in the centre lines x and then y we achieve the same as a single reflection in the lines y = x and y = - x. or to state it another way, we exchange the numbers with their opposite numbers equidistant from the centre along the diagonals ( see figure 3 ). we have exchanged two pairs in each row and column of the square and the results is a magic square. the 6 by 6 magic square is constructed in the same manner, but here t = 3, hence we have much more freedom in our choice of pairs for each column and row. we exchange all the pairs on the diagonal, which is equivalent to exchanging two pairs from each pair of rows and columns, so we must now exchange one more pair from each pair of rows and columns to equalise them. one such choice in the construction of a 6 by 6 magic square is shown in figures 4, 5 and 6 below. exchange the pairs in the diagonals. here we equalise the rows before the columns, the opposite order to that discussed in the text. it can be done in any order. exchange the pairs in the columns. exchange the pairs in the rows. how many other choices we have is possible to calculate, but i will leave that for another time. in the meantime try making a 7 by 7 magic square, or a 8 by 8, or a 10 by 10, or.... the next article in the series is magic squares ii.


check your avocado nutrition iq you love hass avocados for their decadent creamy texture, great taste and versatility, but do you know about the additional benefits hass avocados can provide when incorporated into your daily diet? test your avocado nutrition knowledge and see how you score. you are on question number : the avocado is virtually the only fruit that has monounsaturated fat. monounsaturated fats are one of two types of fats that the avocado contributes to your daily diet that are considered as " good fats ". what is the other type of fat? hint : according to the american heart association, good fats are those that can lower bad cholesterol levels and are beneficial when consumed in moderation. how many calories are in a 1 - ounce serving of avocado? avocados are included in fruits & veggies - more matters® consumer educational program to promote increased consumption of fruits and vegetables for good health because they are : how much cholesterol and sodium is in a 1 - oz serving of avocado? why are avocados considered to act as a " nutrient booster " when eaten with other foods avocados are a good way to get more lutein in the diet. lutein may help maintain the health of what body part? a 1 - oz serving of avocado contains which of the following? thank you for taking our quiz! we hope that you enjoyed our avocado nutrition knowledge quiz. you scored x out of x! sign - up for our free recipe newsletter to get hass avocado recipes, entertaining tips and more nutrition facts each month.


bioethics 101 provides a systematic, five - lesson introductory course to support educators in incorporating bioethics into the classroom through the use of sequential, day - to - day lesson plans. this curriculum is designed to help science teachers in guiding their students to analyze issues using scientific facts, ethical principles, and reasoned judgment. these lessons represent a " best of " compilation from our popular ethics primer. through the use of case studies, ethical principles, decision - making frameworks and stakeholder role - play, students are fully supported in learning how to justify an answer to an ethical question. if you ’ ve been looking for a structured way to introduce bioethics into your classroom, this resource is for you! in order for us to measure how our curriculum resources are being used, please take a moment to contact us and let us know the class or classes in which you ' re using our lessons. we also welcome feedback about our bioethics 101 curriculum. we will not share your contact information with anyone. complete lesson plans lesson 1 - - introduction to bioethics nwabr _ bioethics _ 101 _ lesson1. pdf lesson 2 - - principles of bioethics nwabr _ bioethics _ 101 _ lesson2 _ 0. pdf lesson 3 - - finding the stakeholders nwabr _ bioethics _ 101 _ lesson3. pdf lesson 4 - - making a strong justification nwabr _ bioethics _ 101 _ lesson4. pdf lesson 5 - - putting it all together nwabr _ bioethics _ 101 _ lesson5. pdf this page is coming soon!


ohio coastal design manual promote better projects along the coast that balance the use of lake erie as a shared natural resource along with the property owners ’ need for lakefront erosion protection and the benefit of access to the lake. the odnr office of coastal management has prepared the print and online versions of the coastal design manual to promote better projects along the ohio shore of lake erie including maumee bay and sandusky bay. the manual demonstrates how structures along the shore of lake erie are designed and how coastal engineering principles are best applied to achieve a balance between landowners ’ needs for erosion control and lake access and the need to protect our lake ’ s natural resources. - general vicinity map - identification of adjoining and nearby property owners - history of the site - site conditions and existing structures - the coastal erosion area designation and erosion at the site - geology of the upland - site drainage - characteristics of the shore - types of coastal habitat - habitat considerations - nearshore bathymetry - performance of nearby structures - site wave climate - horizontal and vertical datums - existing site conditions and structures - determination of the parcel boundaries for the site - depicting the littoral partitions between adjoiners for the site - survey products for projects the under regulatory authority of odnr - metes and bounds descriptions - plat of survey for the submerged lands lease parcel - surveyor ’ s role during project construction - post construction survey - design water levels - design wave height run - up and overtopping of structures - changes to the littoral system - effects on adjacent or nearby properties - impact of design on habitat - other design considerations in the general arrangement of structures - design drawings, design specifications and supporting information - suggested standards for engineering and surveying drawings - suggested standards for engineering methods and design calculations - suggested standards for material specifications - suggested standards for supporting information - 4. 1 general design guidelines for erosion control structures - protection against wave - based erosion - protection against upland erosion - 4. 2 armor stone revetment design - armor material - armor layer - crest elevation - filter layer function - filter layer design - 4. 3 seawalls - general considerations - design components - wall & cap height - run - up & overtopping - sliding & overturning - overturning safety factor - pre - cast concrete block seawall design - block seawall structural design - steel frame crib design - 4. 4 construction, inspection & maintenance - inspection and monitoring - maintenance and repair 4. 5 design examples the ohio department of natural resources ( odnr ) office of coastal


revised code section 1506. 40 ). documents ( metes and bounds descriptions and plats ) required to enter into a submerged lands lease with the state of ohio must be prepared and sealed by a professional surveyor licensed by the state of ohio. professional engineers ( pe ) and professional surveyors ( ps ) are licensed by the state of ohio only after demonstrating technical knowledge and actual engineering / surveying experience. the act of signing and sealing a design drawing by an engineer or surveyor is a statement certifying that the work has been prepared with direct supervisory control and according to the best professional standards. it is an assurance to both the property owner and to the agency that receives the drawings that the work has adhered to appropriate design standards, is protective of the public welfare, and safeguards life, health and property. many property owners are familiar with building houses and other structures on land, where contractors “ pull ” permits from the local building authority without the need for sealed plans from a pe. this process is supported by a system of very protective and conservative building codes and inspections that ensure buildings are both well designed and constructed with appropriate setbacks from property boundaries. no similar system of codes and inspections exists for structures built along the shore of lake erie. the design of coastal structures is not always as straight - forward as complying with plumbing or electrical codes. many sites have complex geology, drainage issues, structural conditions, and / or wave climates that require careful consideration, planning and design. failure of an erosion control structure, even over a period of years, may result in loss of additional upland, may threaten existing buildings, and can result in damage to adjacent properties. the repair of a failed structure may be as expensive as the original construction. the planning of a project also requires a field survey. the surveyor is best suited to provide the critical site information needed by the pe for design. this includes existing site contours, the location, dimensions and elevations of structures, and the offshore bathymetry. a surveyor is needed to determine the boundary of the upland parcel and the partition lines for littoral rights extending into the lake. if a submerged lands lease is needed, a ps prepares a metes and bounds description and plat. these products can only be prepared by an ohio registered ps. references, resources and other design manuals in most cases, important references are noted as part of the discussion in a given chapter. design equations, charts and tables included in this manual have been drawn from numerous sources and reflect ocm ’ s understanding of the state of the