- weak drug regulatory control and enforcement ; - scarcity and / or erratic supply of basic medicines ; - unregulated markets and distribution chains ; - high drug prices and / or - significant price differentials. at national level, governments, law enforcement agencies, heath professionals, the pharmaceutical industry, importers, distributors, and consumer organizations should adopt a shared responsibility in the fight against counterfeit drugs. cooperation between countries, especially trading partners is very useful for combating counterfeiting. cooperation should include the timely and appropriate exchange of information and the harmonization of measures to prevent the spread of counterfeit medicines. the world health organization has developed and published guidelines, guidelines for the development of measures to combat counterfeit medicines. these guidelines provide advice on measures that should be taken by the various stakeholders and interested parties to combat counterfeiting of medicines. governments and all stakeholders are encouraged to adapt or adopt these guidelines in their fight against counterfeiting of medicines. - guidelines for the development of measures to combat counterfeit medicines - rapid alert system for counterfeit medicines communication and advocacy - creating public awareness patients and consumers are the primary victims of counterfeit medicines. in order to protect them from the harmful effects of counterfeit medicines it is necessary to provide them with appropriate information and education on the consequences of counterfeit medicines. patients and consumers expect to get advice from national authorities, health - care providers, health professionals and others from where they should buy or get their medicines ; what measures they should take in case they come across such medicines or are affected by the use of such medicines. ministries of health, national medicines regulators, health professional associations, nongovernmental organizations and other stakeholders have the responsibility to participate in campaign activities targeting patients and consumers to promote awareness of the problem of counterfeit medicines. posters, brochures, radio and television programmes are useful means for disseminating messages and advice.


click the picture above to see three larger pictures show birthplace location | previous | | ( alphabetically ) | | next | | biographies index | | version for printing | lipman bers, always known as lipa, was born into a jewish family. his parents isaac bers and bertha weinberg were teachers, his mother being head at an elementary school in riga where teaching was in yiddish while his father was head at the yiddish high school in riga. born in 1914, lipa ' s early years were much affected by the political and military events taking place in russia. latvia had been under russian imperial rule since the 18th century so world war i meant that there were evacuations from riga. the russian revolution which began in october 1917 caused fighting between the red army and the white army and for the next couple of years various parts of russia came first under the control of one faction then of the other. lipa ' s family went to petrograd, the name that st petersburg had been given in 1914 when there was strong anti - german feeling in russia, but lipa was too young to understand the difficulties that his parents went through at this time. at the end of world war i in 1918, latvia regained its independence although this was to be short - lived. lipa spent some time back in riga, but he also spent time in berlin. his mother took him to berlin while she was training at the psychoanalytic institute. during his schooling mathematics became his favourite subject and he decided that it was the subject he wanted to study at university. he studied at the university of zurich, then returned to riga and studied at the university there. at this time europe was a place of extreme politics and, in 1934, latvia became ruled by a dictator. lipa was a political activist, a social democrat who argued strongly for human rights. he was at this time a soap - box orator putting his views across strongly both in speeches and in writing for an underground newspaper. strongly opposed to dictators and strongly advocating democracy it was clear that his criticism of the latvian dictator could not be ignored by the authorities. a warrant was issued for his arrest and, just in time, he escaped to prague. his girl friend mary kagan followed him to prague where they married on 15 may 1938. there were a number of reasons why bers chose to go to prague at this time. firstly he had to escape from latvia, secondly prague was in a democratic country, and thirdly his aunt lived there so he could obtain permission to study at the charles university


a number of reasons why bers chose to go to prague at this time. firstly he had to escape from latvia, secondly prague was in a democratic country, and thirdly his aunt lived there so he could obtain permission to study at the charles university without having to find a job to support himself. one should also not underestimate the fact that by this stage his mathematical preferences were very much in place and karl loewner in prague looked the ideal supervisor. indeed bers did obtain his doctorate which was awarded in 1938 from the charles university of prague where he wrote a thesis on potential theory under karl loewner ' s supervision. at the time bers was rather unhappy with loewner : - lipa spoke of feeling neglected, perhaps even not encouraged, by loewner and said that only in retrospect did he understand loewner ' s teaching method. he gave to each of his students the amount of support needed... it is obvious that lipa did not appear too needy to loewner. in 1938 czechoslovakia became an impossible country for someone of jewish background. equally dangerous was the fact that bers had no homeland since he was a wanted man in latvia, and was a left wing academic. with little choice but to escape again, bers fled to paris where his daughter ruth was born. however, the war followed him and soon the nazi armies began occupying france. bers applied for a visa to the usa and, while waiting to obtain permission, he wrote two papers on green ' s functions and integral representations. just days before paris surrendered to the advancing armies, bers and his family moved from paris to a part of france not yet under attack from the advancing german armies. at last he received the news that he was waiting for, the issue of american visas for his family. in 1940 bers and his family arrived in the united states and joined his mother who was already in new york. there was of course a flood of well qualified academics arriving in the united states fleeing from the nazis and there was a great scarcity of posts, even for the most brilliant, so he was unemployed until 1942, living with other unemployed refugees in new york. during this time he continued his mathematical researches. after this he was appointed research instructor at brown university where, as part of work relevant to the war effort, he studied two - dimensional subsonic fluid flow. this was important at that time since aircraft wings were being designed for planes with jet engines capable of high speeds. between 1945 and 1949 bers worked at


as part of work relevant to the war effort, he studied two - dimensional subsonic fluid flow. this was important at that time since aircraft wings were being designed for planes with jet engines capable of high speeds. between 1945 and 1949 bers worked at syracuse university, first at assistant professor, later as associate professor. gelbart wanted to build up the department at syracuse and attracting both bers and loewner was an excellent move. here bers began work on the problem of removability of singularities of non - linear elliptic equations. his major results in this area were announced by him at the international congress of mathematicians in 1950 and his paper isolated singularities of minimal surfaces was published in the annals of mathematics in 1951. courant writes : - the nonparametric differential equation of minimal surfaces may be considered the most accessible significant example revealing typical qualities of solutions of non - linear partial differential equations. with a view to such a general objective, [ bers ] has studied singularities, branch - points and behaviour in the large of minimal surfaces. abikoff writes in that this paper is : -... a magnificent synthesis of complex analytic techniques which relate the different parameterisations of minimal surfaces to the representations of the potential function for subsonic flow and thereby achieves the extension across the singularity. bers then became a member of the institute for advanced study at princeton where he began work on teichmuller theory, pseudoanalytic functions, quasiconformal mappings and kleinian groups. he was set in the right direction by an inequality he found in a paper of lavrentev who attributed the inequality to ahlfors. in a lecture he gave in 1986 bers explained what happened next : - i was in princeton at the time. ahlfors came to princeton and announced a talk on quasiconformal mappings. he spoke at the university so i went there and sure enough, he proved this theorem. so i came up to him after the talk and asked him " where did you publish it? ", and he said " i didn ' t ". " so why did lavrentev credit you with it? " ahlfors said " he probably thought i must know it and was too lazy to look it up in the literature ". when bers met lavrentev three years later he asked him the same questions and, indeed, ahlfors had been correct in guessing why lavrentev had credited him. bers continued in his 1986 lecture :


the literature ". when bers met lavrentev three years later he asked him the same questions and, indeed, ahlfors had been correct in guessing why lavrentev had credited him. bers continued in his 1986 lecture : - i immediately decided that, first of all, if quasiconformal mappings lead to such powerful and beautiful results and, secondly, if it is done in this gentlemanly spirit - where you don ' t fight over priority - this is something that i should spend the rest of my life studying. it is ironic, given bers strong political views on human rights, that he should find that teichmuller, a fervent nazi, had already made stunning contributions. in one of his papers on teichmuller theory, bers quotes plutarch : - it does not of necessity follow that, if the work delights you with its grace, the one who wrought it is worthy of your esteem. in 1951 bers went to the courant institute in new york, where he was a full professor, and remained there for 13 years. during this time he wrote a number of important books and surveys on his work. he published theory of pseudo - analytic functions in 1953 which protter, in a review, described as follows : - the theory of pseudo - analytic functions was first announced by [ bers ] in two notes. these lecture notes not only contain proofs and extensions of the results previously announced but give a self - contained and comprehensive treatment of the subject. the author sets as his goal the development of a function theory for solutions of linear, elliptic, second order partial differential equations in two independent variables ( or systems of two first - order equations ). one of the chief stumbling blocks in such a task is the fact that the notion of derivative is a hereditary property for analytic functions while this is clearly not the case for solutions of general second order elliptic equations. another classic text was mathematical aspects of subsonic and transonic gas dynamics published in 1958 : - it should be said, even though this is taken for granted by everybody in the case of professor bers, that the survey is masterly in its elegance and clarity. in 1958 bers address the international congress of mathematicians in edinburgh, scotland, where he lectured on spaces of riemann surfaces and announced a new proof of the measurable riemann mapping theorem. in his talk bers summarised recent work on the classical problem of moduli for compact riemann surfaces and sketched a proof of the te


on spaces of riemann surfaces and announced a new proof of the measurable riemann mapping theorem. in his talk bers summarised recent work on the classical problem of moduli for compact riemann surfaces and sketched a proof of the teichmuller theorem characterizing extremal quasiconformal mappings. he showed that the teichmuller space for surfaces of genus g is a ( 6g - 6 ) - cell, and showed how to construct the natural complex analytic structure for the teichmuller space. bers was a guggenheim fellow in 1959 - 60, and a fulbright fellow in the same academic year. from 1959 until he left the courant institute in 1964, bers was chairman of the graduate department of mathematics. in 1964 bers went to columbia university where he was to remain until he retired in 1984. he was chairman of the department from 1972 to 1975. he was appointed davies professor of mathematics in 1972, becoming emeritus davies professor of mathematics in 1982. during this period bers was visiting miller research professor at the university of california at berkeley in 1968. tilla weinstein describes in bers as a lecturer : - lipa ' s courses were irresistible. he laced his lectures with humorous asides and tasty tidbits of mathematical gossip. he presented intricate proofs with impeccable clarity, pausing dramatically at the few most critical steps, giving us a chance to think for ourselves and to worry that he might not know what to do next. then, just as the silence got uncomfortable, he would describe the single most elegant way to complete the argument. jane gilman describes bers ' character : - underneath the force of bers ' personality and vivacity was the force of his mathematics. his mathematics had a clarity and beauty that went beyond the actual results. he had a special gift for conceptualising things and placing them in the larger context. in bers life is summed up by abikoff as follows : - lipa possessed a joy of life and an optimism that is difficult to find at this time and that is sorely missed. those of us who experienced it directly have felt an obligation to pass it on. that, in addition to the beauty of his own work, is lipa ' s enduring gift to us. we have yet to say something about bers ' great passion for human rights. in fact this was anything but a sideline in his life and one could consider that he devoted himself full - time to both his mathematical work and to his work as


. we have yet to say something about bers ' great passion for human rights. in fact this was anything but a sideline in his life and one could consider that he devoted himself full - time to both his mathematical work and to his work as a social reformer. perhaps his views are most clearly expressed by quoting from an address he gave in 1984 when awarded an honorary degree by the state university of new york at stony brook : - by becoming a human rights activist... you do take upon yourself certain difficult obligations.... i believe that only a truly even - handed approach can lead to an honest, morally convincing, and effective human rights policy. a human rights activist who hates and fears communism must also care about the human rights of latin american leftists. a human rights activist who sympathises with the revolutionary movement in latin america must also be concerned about human rights abuses in cuba and nicaragua. a devout muslim must also care about human rights of the bahai in iran and of the small jewish community in syria, while a jew devoted to israel must also worry about the human rights of palestinian arabs. and we american citizens must be particularly sensitive to human rights violations for which our government is directly or indirectly responsible, as well as to the human rights violations that occur in our own country, as they do. bers received many honours for his contributions in addition to those we have mentioned above. he was elected to the american academy of arts and sciences, to the finnish academy of sciences, and to the american philosophical society. he served the american mathematical society in several capacities, particularly as vice - president ( 1963 - 65 ) and as president ( 1975 - 77 ). the american mathematical society awarded him their steele prize in 1975. he received the new york mayor ' s award in science and technology in 1985. he was an honorary life member of the new york academy of sciences, and of the london mathematical society. article by : j j o ' connor and e f robertson click on this link to see a list of the glossary entries for this page list of references ( 5 books / articles ) | | some quotations ( 3 ) | | mathematicians born in the same country | | honours awarded to lipman bers | ( click below for those honoured in this way ) | ams colloquium lecturer | | 1971 | | ams steele prize | | 1975 | | american maths society president | | 1975 - 1976 | | lms honorary member | | 1984 | other web sites | previous | | ( alphabetically


x2 / 3 + y2 / 3 = a2 / 3 x = a cos3 ( t ), y = a sin3 ( t ) click below to see one of the associated curves. | definitions of the associated curves | | evolute | | involute 1 | | involute 2 | | inverse curve wrt origin | | inverse wrt another circle | | pedal curve wrt origin | | pedal wrt another point | | negative pedal curve wrt origin | | negative pedal wrt another point | | caustic wrt horizontal rays | | caustic curve wrt another point | the astroid only acquired its present name in 1836 in a book published in vienna. it has been known by various names in the literature, even after 1836, including cubocycloid and paracycle. the length of the astroid is 6a and its area is 3πa2 / 8. the gradient of the tangent t from the point with parameter p is - tan ( p ). the equation of this tangent t is x sin ( p ) + y cos ( p ) = a sin ( 2p ) / 2 let t cut the x - axis and the y - axis at x and y respectively. then the length xy is a constant and is equal to a. it can be formed by rolling a circle of radius a / 4 on the inside of a circle of radius a. it can also be formed as the envelope produced when a line segment is moved with each end on one of a pair of perpendicular axes. it is therefore a glissette. other web site : | main index | | famous curves index | | previous curve | | next curve | | history topics index | | birthplace maps | | mathematicians of the day | | anniversaries for the year | | societies, honours, etc | | search form | the url of this page is :


the machete blades turned red with heat in the fire that the rubber workers built on a liberia plantation, thomas unnasch remembers from a visit in the 1980s. this was how the men tried to quell the intense itchiness that comes with river blindness, a rare tropical disease. " you can imagine how bad the itching must be, that running a red - hot machete up and down your back would be a relief, but it was, " said unnasch, whose laboratory works on diagnostic tests for the disease. about 18 million people have river blindness worldwide, according to the world health organization, but more than 99 % of cases of this disease are found in africa. it goes by the technical name " onchocerciasis, " and it spreads through small black flies that breed in fast - flowing, highly oxygenated waters. when an infected fly bites a person, it drops worm larvae in the skin, which can then grow and reproduce in the body. unlike malaria, river blindness is not fatal, but it causes a " miserable life, " said moses katabarwa, senior epidemiologist for the atlanta - based carter center ' s river blindness program, which has been leading an effort to eliminate the disease in the americas and several african countries. some strains cause blindness, while others come with more severe skin disease. with time, generally all strains of the disease can lead to rough " lizard " skin, depigmented " leopard skin " and hanging groins. another big problem among patients is itching, which happens when the worms die inside a person. in southwest uganda, the locals call the disease " obukamba, " referring to the symptoms of distorted skin appearance and itchiness, katabarwa said. in western uganda, he said, " the fly is called ' embwa fly ' or dog fly, for it bites like a dog! " there is no vaccine for river blindness, but there is a drug, called ivermectin that paralyzes and kills the offspring of adult worms, according to the mayo clinic. it may also slow the reproduction of adult female worms, so there are fewer of them in the skin, blood and eyes. the pharmaceutical company merck has been donating the treatment, under the brand name mectizan, since 1985. great strides have been made against this disease. in the americas, it was eliminated in colombia in 2007 and in ecuador in 2009.


attention deficit hyperactivity disorder or adhd is a common childhood illness. people who are affected can have trouble with paying attention, sitting still and controlling their impulses. there are three types of adhd. the most common type of adhd is when people have difficulties with both attention and hyperactivity. this is called adhd combined type. some people only have difficulty with attention and organization. this is adhd inattentive subtype or attention deficit disorder ( add ). other people have only the hyperactive and impulsive symptoms. this is adhd hyperactive subtype. it is a health condition involving biologically active substances in the brain. studies show that adhd may affect certain areas of the brain that allow us to solve problems, plan ahead, understand others ' actions, and control our impulses. many children and adults are easily distracted at times or have trouble finishing tasks. if you suspect that your child has adhd, it is important to have your child evaluated by his or her doctor. in order for your child ’ s doctor to diagnose your child with adhd, the behaviors must appear before age 7 and continue for at least six months. the symptoms must also create impairment in at least two areas of the child ' s life - in the classroom, on the playground, at home, in the community, or in social settings. many children have difficulties with their attention but attention problems are not always cue to adhd. for example, stressful life events and other childhood conditions such as problems with schoolwork caused by a learning disability or anxiety and depression can interfere with attention. according to the national institute of mental health, adhd occurs in an estimated 3 to 5 percent of preschool and school - age children. therefore, in a class of 25 to 30 children, it is likely that at least one student will have this condition. adhd begins in childhood, but it often lasts into adulthood. several studies done in recent years estimate that 30 to 65 percent of children with adhd continue to have symptoms into adolescence and adulthood. no one knows exactly what causes adhd. there appears to be a combination of causes, including genetics and environmental influences several different factors could increase a child ' s likelihood of having the disorder, such as gender, family history, prenatal risks, environmental toxins and physical differences in the brain seem to be involved. a child with adhd often shows some of the following : difficulties with attention : - trouble paying attention - inattention to details and makes careless mistakes - easily distracted -


risks, environmental toxins and physical differences in the brain seem to be involved. a child with adhd often shows some of the following : difficulties with attention : - trouble paying attention - inattention to details and makes careless mistakes - easily distracted - losing things such as school supplies - forgetting to turn in homework - trouble finishing class work and homework - trouble listening - trouble following multiple adult commands - difficulty playing quietly - inability to stay seated - running or climbing excessively - always " on the go " - talks too much and interrupts or intrudes on others - blurts out answers the good news is that effective treatment is available. the first step is to have a careful and thorough evaluation with your child ’ s primary care doctor or with a qualified mental health professional. with the right treatment, children with adhd can improve their ability to pay attention and control their behavior. the right care can help them grow, learn, and feel better about themselves. medications : most children with adhd benefit from taking medication. medications do not cure adhd. medications can help a child control his or her symptoms on the day that the pills are taken. medications for adhd are well established and effective. there are two main types : stimulant and non - stimulant medications. stimulants include methylphenidate, and amphetamine salts. non - stimulant medications include atomoxetine. for more information about the medications used to treat adhd, please see the parent med guide. before medication treatment begins, your child ' s doctor should discuss the benefits and the possible side effects of these medications. your child ’ s doctor should continue to monitor your child for improvement and side effects. a majority of children who benefit from medication for adhd will continue to benefit from it as teenagers. in fact, many adults with adhd also find that medication can be helpful. therapy and other support : a psychiatrist or other qualified mental health professional can help a child with adhd. the psychotherapy should focus on helping parents provide structure and positive reinforcement for good behavior. in addition, individual therapy can help children gain a better self - image. the therapist can help the child identify his or her strengths and build on them. therapy can also help a child with adhd cope with daily problems, pay better attention, and learn to control aggression. a therapist may use one or more of the following approaches : behavior therapy, talk therapy, social skills training, family support groups. sometimes children and parents wonder when children can stop taking


with daily problems, pay better attention, and learn to control aggression. a therapist may use one or more of the following approaches : behavior therapy, talk therapy, social skills training, family support groups. sometimes children and parents wonder when children can stop taking adhd medication. if you have questions about stopping adhd medication, consult your doctor. many children diagnosed with adhd will continue to have problems with one or more symptoms of this condition later in life. in these cases, adhd medication can be taken into adulthood to help control their symptoms. for others, the symptoms of adhd lessen over time as they begin to " outgrow " adhd or learn to compensate for their behavioral symptoms. the symptom most apt to lessen over time is hyperactivity. some signs that your child may be ready to reduce or stop adhd medication are : - your child has been symptom - free for more than a year while on medication, - your child is doing better and better, but the dosage has stayed the same, - your child ' s behavior is appropriate despite missing a dose or two, - or your child has developed a newfound ability to concentrate. the choice to stop taking adhd medication should be discussed with the prescribing doctor, teachers, family members, and your child. you may find that your child needs extra support from teachers and family members to reinforce good behavior once the medication is stopped. without treatment, a child with adhd may fall behind in school and have trouble with friendships. family life may also suffer. untreated adhd can increase strain between parents and children. parents often blame themselves when they can ' t communicate with their child. the sense of losing control can be very frustrating. teenagers with adhd are at increased risk for driving accidents. adults with untreated adhd have higher rates of divorce and job loss, compared with the general population. luckily, safe and effective treatments are available which can help children and adults help control the symptoms of adhd and prevent the unwanted consequences.


weights linked to lower diabetes risk weight gains weight training, and not just cardio workouts, is linked to a lower risk of developing type 2 diabetes, according to a us study. " we all know that aerobic exercise is beneficial for diabetes - many studies have looked at that - but no studies have looked at weight training, " says study leader frank hu, at the harvard school of public health. " this study suggests that weight training is important for diabetes, and probably as important as aerobic training. " hu and his colleagues, whose report was published in the archives of internal medicine, used data on more than 32, 000 male health professionals, who answered questionnaires every two years from 1990 to 2008. on average, four out of 1000 men developed type 2 diabetes every year, the researchers found. the risk of getting the blood sugar disorder was only half as high for men who did cardio, or aerobic, workouts - say brisk walking, jogging or playing tennis - at least 150 minutes a week, as for those who didn ' t do any cardio exercise. men who did weight training for 150 minutes or more had a risk reduction of a third compared to those who never lifted weights, independently of whether or not they did aerobic exercise. exercise is beneficial whereas weight training increases muscle mass and can reduce abdominal obesity, it tends not to cut overall body mass, says hu. the results don ' t prove that working out staves off diabetes, because many men who stay fit may also be healthier in other ways, but the researchers did their best to account for such potential differences, including age, smoking and diet. " i think the benefits of weight training are real, " says hu. " any type of exercise is beneficial for diabetes prevention, but weight training can be incorporated with aerobic exercise to get the best results. " along with an appropriate diet, exercise is also important for people who already have type 2 diabetes and can help control high blood sugar, he adds.


arctic meltdown not caused by nature rapid loss of arctic sea ice - 80 per cent has disappeared since 1980 - is not caused by natural cycles such as changes in the earth ' s orbit around the sun, says dr karl. the situation is getting rather messy with regard to the ice melting in the arctic. now the volume of the ice varies throughout the year, rising to its peak after midwinter, and falling to its minimum after midsummer, usually in the month of september. over most of the last 1, 400 years, the volume of ice remaining each september has stayed pretty constant. but since 1980, we have lost 80 per cent of that ice. now one thing to appreciate is that over the last 4. 7 billion years, there have been many natural cycles in the climate — both heating and cooling. what ' s happening today in the arctic is not a cycle caused by nature, but something that we humans did by burning fossil fuels and dumping slightly over one trillion tonnes of carbon into the atmosphere over the last century. so what are these natural cycles? there are many many of them, but let ' s just look at the milankovitch cycles. these cycles relate to the earth and its orbit around the sun. there are three main milankovitch cycles. they each affect how much solar radiation lands on the earth, and whether it lands on ice, land or water, and when it lands. the first milankovitch cycle is that the orbit of the earth changes from mostly circular to slightly elliptical. it does this on a predominantly 100, 000 - year cycle. when the earth is close to the sun it receives more heat energy, and when it is further away it gets less. at the moment the orbit of the earth is about halfway between " nearly circular " and " slightly elliptical ". so the change in the distance to the sun in each calendar year is currently about 5. 1 million kilometres, which translates to about 6. 8 per cent difference in incoming solar radiation. but when the orbit of the earth is at its most elliptical, there will be a 23 per cent difference in how much solar radiation lands on the earth. the second milankovitch cycle affecting the solar radiation landing on our planet is the tilt of the north - south spin axis compared to the plane of the orbit of the earth around the sun. this tilt rocks gently between 22. 1 degrees and 24. 5 degrees from the vertical. this cycle has a period of about 41, 000 years. at the moment we are roughly halfway in the middle — we '


of the earth around the sun. this tilt rocks gently between 22. 1 degrees and 24. 5 degrees from the vertical. this cycle has a period of about 41, 000 years. at the moment we are roughly halfway in the middle — we ' re about 23. 44 degrees from the vertical and heading down to 22. 1 degrees. as we head to the minimum around the year 11, 800, the trend is that the summers in each hemisphere will get less solar radiation, while the winters will get more, and there will be a slight overall cooling. the third milankovitch cycle that affects how much solar radiation lands on our planet is a little more tricky to understand. it ' s called ' precession '. as our earth orbits the sun, the north - south spin axis does more than just rock gently between 22. 1 degrees and 24. 5 degrees. it also — very slowly, just like a giant spinning top — sweeps out a complete 360 degrees circle, and it takes about 26, 000 years to do this. so on january 4, when the earth is at its closest to the sun, it ' s the south pole ( yep, the antarctic ) that points towards the sun. so at the moment, everything else being equal, it ' s the southern hemisphere that has a warmer summer because it ' s getting more solar radiation, but six months later it will have a colder winter. and correspondingly, the northern hemisphere will have a warmer winter and a cooler summer. but of course, " everything else " is not equal. there ' s more land in the northern hemisphere but more ocean in a southern hemisphere. the arctic is ice that is floating on water and surrounded by land. the antarctic is the opposite — ice that is sitting on land and surrounded by water. you begin to see how complicated it all is. we have had, in this current cycle, repeated ice ages on earth over the last three - million years. during an ice age, the ice can be three kilometres thick and cover practically all of canada. it can spread through most of siberia and europe and reach almost to where london is today. of course, the water to make this ice comes out of the ocean, and so in the past, the ocean level has dropped by some 125 metres. from three million years ago to one million years ago, the ice advanced and retreated on a 41, 000 - year cycle. but from one million years ago until the present, the ice has advanced and retreated on a 100, 000 - year cycle. what


black holes growing faster than expected black hole find existing theories on the relationship between the size of a galaxy and its central black hole are wrong according to a new australian study. the discovery by dr nicholas scott and professor alister graham, from melbourne ' s swinburne university of technology, found smaller galaxies have far smaller black holes than previously estimated. central black holes, millions to billions of times more massive than the sun, reside in the core of most galaxies, and are thought to be integral to galactic formation and evolution. however astronomers are still trying to understand this relationship. scott and graham combined data from observatories in chile, hawaii and the hubble space telescope, to develop a data base listing the masses of 77 galaxies and their central supermassive black holes. the astronomers determined the mass of each central black hole by measuring how fast stars are orbiting it. existing theories suggest a direct ratio between the mass of a galaxy and that of its central black hole. " this ratio worked for larger galaxies, but with improved technology we ' re now able to examine far smaller galaxies and the current theories don ' t hold up, " says scott. in a paper to be published in the astrophysical journal, they found that for each ten - fold decrease in a galaxy ' s mass, there was a one hundred - fold decrease in its central black hole mass. " that was a surprising result which we hadn ' t been anticipating, " says scott. the study also found that smaller galaxies have far denser stellar populations near their centres than larger galaxies. according to scott, this also means the central black holes in smaller galaxies grow much faster than their larger counterparts. black holes grow by merging with other black holes when their galaxies collide. " when large galaxies merge they double in size and so do their central black holes, " says scott. " but when small galaxies merge their central black holes quadruple in size because of the greater densities of nearby stars to feed on. " somewhere in between the findings also solve the long standing problem of missing intermediate mass black holes. for decades, scientists have been searching for something in between stellar mass black holes formed when the largest stars die, and supermassive black holes at the centre of galaxies. " if the central black holes in smaller galaxies have lower mass than originally thought, they may represent the intermediate mass black hole population astronomers have been hunting for, " says graham. " intermediate sized black holes are between ten thousand and a few hundred thousand times the mass of the sun, and we think we '


hoodoos may be seismic gurus hoodoo prediction towering chimney - like sedimentary rock spires known as hoodoos may provide an indication of an area ' s past earthquake activity. the research by scientists including dr rasool anooshehpoor, from the united states nuclear regulatory commission, may provide scientists with a new tool to test the accuracy of current hazard models. hoodoo formations are often found in desert regions, and are common in north america, the middle east and northern africa. they are caused by the uneven weathering of different layers of sedimentary rocks, that leave boulders or thin caps of hard rock perched on softer rock. by knowing the strengths of different types of sedimentary layers, scientists can determine the amount of stress needed to cause those rocks to fracture. the united states geological survey ( usgs ) use seismic hazard models to predict the type of ground motion likely to occur in an area during a seismic event. but, according to anooshehpoor, these models lack long term data. " existing hazard maps use models based on scant data going back a hundred years or so, " says anooshehpoor. " but earthquakes have return periods lasting hundreds or thousands of years, so there is nothing to test these hazard models against. " the researchers examined two unfractured hoodoos within a few kilometres of the garlock fault, which is an active strike - slip fault zone in california ' s red rock canyon. their findings are reported in the bulletin of the seismological society of america. " although we can ' t put a precise age on hoodoos because of their erosion characteristics, we can use them to provide physical limits on the level of ground shaking that could potentially have occurred in the area, " says anooshehpoor. the researchers developed a three - dimensional model of each hoodoo and determined the most likely place where each spire would fail in an earthquake. they then tested rock samples similar to the hoodoo pillars to measure their tensile strength and compared their results with previously published data. usgs records suggest at least one large magnitude earthquake occurred along the fault in the last 550 years, resulting in seven metres of slip, yet the hoodoos are still standing. this finding is consistent with a median level of ground motion associated with the large quakes in this region, says anooshehpoor. " if an earthquake occurred with a higher level of ground motion, the hoodoos would have collapsed, " he says. " nobody can predict earthquakes


now, it is common knowledge these days that hitler ' s final great offensive in the last years of wwii was the ardennes offensive of 1944 / 45, also known as the battle of the bulge. what was not appreciated at the time by the allied high command was just how desperately short of vital supplies the third reich armies actually were. the ardennes offensive was hitler ' s bold attempt to capture and hold the allied army ' s massive supply of brussels sprouts, vital - of course - for the full functioning of any army. german intelligence were aware that the american army was - in particular - massing huge quantities of the vital brussels sprouts just behind their frontlines in preparedness for their own massive push - and - of course - in time for christmas. the german ' s audacious plan would have succeeded if the allies had not quickly worked out that it was their stockpiles of brussels sprouts that were under immediate threat. the bold plan put forward by the allied generals was a heavy gamble, but it paid off. they ordered their front - line chefs to begin boiling their entire stocks of brussels sprouts, and - most importantly - to keep them boiling well past a state of fully preparedness. so, when the weather altered and the wind direction changed, it blew the smell of over - cooked brussels sprouts straight into the faces of the advancing germans. then the reich troops knew that they would not be able to replenish their stocks of brussels sprouts and any sprouts that they did capture from the allied frontline kitchens would be overcooked to the point of inedibility. later in this series, we will discuss the major strategic role that brussels sprouts have played in world history, such as hadrian building a wall to protect the roman empire ' s most northern supplies of brussels sprouts from the northern barbarians, thus thwarting the barbarian ' s fiendish plan to deep - fry the roman ' s entire stockpiles of sprouts. then there was, also, napoleon ' s retreat from moscow when his over - long supply line of brussels sprouts direct from france broke down. even when his troops could get sprouts, they were of poor quality - dry, wizened and frozen solid. of course, this led to a massive collapse of morale. eventually, the lack of good quality sprouts forced a massive retreat where thousands of french troops died from a pitiful lack of sprouts. and, of course,


books yellow, red, and green and blue, all true, or just as good as true, and here ' s the blue book just for you! hard is the path from a to z, and puzzling to a curly head, yet leads to books — green, yellow and red. for every child should understand that letters from the first were planned to guide us into fairy land so labour at your alphabet, for by that learning shall you get to lands where fairies may be met. and going where this pathway goes, you too, at last, may find, who knows? the garden of the singing rose. as to whether there are really any fairies or not, that is a difficult question. the editor never saw any himself, but he knew several people who have seen them - in the highlands - and heard their music. if ever you are in nether lochaber, go to the fairy hill, and you may hear the music your - self, as grown - up people have done, but you must go on a fine day. this book has been especially re - published to raise funds for : the great ormond street hospital children ’ s charity by buying this book you will be donating to this great charity that does so much good for ill children and which also enables families to stay together in times of crisis. and what better way to help children than to buy a book of fairy tales. some have not been seen in print or heard for over a century. 33 % of the publisher ’ s profit from the sale of this book will be donated to the gosh children ’ s charity. yesterdays books for todays charities little red riding hood once upon a time there lived in a certain village a little country girl, the prettiest creature was ever seen. her mother was excessively fond of her ; and her grandmother doted on her still more. this good woman had made for her a little red riding - hood ; which became the girl so extremely well that everybody called her little red riding - hood. one day her mother, having made some custards, said to her : " go, my dear, and see how thy grandmamma does, for i hear she has been very ill ; carry her a custard, and this little pot of butter. " little red riding - hood set out immediately to go to her grandmother, who lived in another village. as she was going through the wood, she met with gaffer wolf, who had a very great mind to eat her up, but he dared


" little red riding - hood set out immediately to go to her grandmother, who lived in another village. as she was going through the wood, she met with gaffer wolf, who had a very great mind to eat her up, but he dared not, because of some faggot - makers hard by in the forest. he asked her whither she was going. the poor child, who did not know that it was dangerous to stay and hear a wolf talk, said to him : " i am going to see my grandmamma and carry her a custard and a little pot of butter from my mamma. " " does she live far off? " said the wolf. " oh! aye, " answered little red riding - hood ; " it is beyond that mill you see there, at the first house in the village. " " well, " said the wolf, " and i ' ll go and see her too. i ' ll go this way and you go that, and we shall see who will be there soonest. " the wolf began to run as fast as he could, taking the nearest way, and the little girl went by that farthest about, diverting herself in gathering nuts, running after butterflies, and making nosegays of such little flowers as she met with. the wolf was not long before he got to the old woman ' s house. he knocked at the door — tap, tap. " your grandchild, little red riding - hood, " replied the wolf, counterfeiting her voice ; " who has brought you a custard and a little pot of butter sent you by mamma. " the good grandmother, who was in bed, because she was somewhat ill, cried out : " pull the bobbin, and the latch will go up. " the wolf pulled the bobbin, and the door opened, and then presently he fell upon the good woman and ate her up in a moment, for it was above three days that he had not touched a bit. he then shut the door and went into the grandmother ' s bed, expecting little red riding - hood, who came some time afterward and knocked at the door — tap, tap. little red riding - hood, hearing the big voice of the wolf, was at first afraid ; but believing her grandmother had got a cold and was hoarse, answered : " ’ tis your grandchild, little red riding - hood, who has brought you a custard and a little pot of butter mamma sends you.


at first afraid ; but believing her grandmother had got a cold and was hoarse, answered : " ’ tis your grandchild, little red riding - hood, who has brought you a custard and a little pot of butter mamma sends you. " the wolf cried out to her, softening his voice as much as he could : " pull the bobbin, and the latch will go up. " little red riding - hood pulled the bobbin, and the door opened. the wolf, seeing her come in, said to her, hiding himself under the bed - clothes : " put the custard and the little pot of butter upon the stool, and come and lie down with me. " little red riding - hood undressed herself and went into bed, where, being greatly amazed to see how her grandmother looked in her night - clothes, she said to her : " grandmamma, what great arms you have got! " " that is the better to hug thee, my dear. " " grandmamma, what great legs you have got! " " that is to run the better, my child. " " grandmamma, what great ears you have got! " " that is to hear the better, my child. " " grandmamma, what great eyes you have got! " " it is to see the better, my child. " " grandmamma, what great teeth you have got! " " that is to eat thee up. " and, saying these words, this wicked wolf fell upon little red riding - hood, and tried to start eating her. red riding hood screamed “ someone help me! ” over and over again. the woodcutter, who was felling trees nearby, heard red riding hood ’ s screams for help and ran to the cottage. he burst in to find the wolf trying to eat red riding hood. he swung his axe, and with one blow killed the bad wolf for which red riding hood was ever so grateful. great book! really interesting read! was great to see a published version of jewish tales! arrived very quickly too - great service! a thrilling book about a chase across the us! a great story, my son loved it! quick and convenient delivery! stories of the famous spice route across asia! great to see a volume of phillipine folklore stories in print, only one i ' ve found on the web! we deliver to destinations all over the world, and here at abela, we have some of the best rates in the book industry. we charge shipping dependant


what exactly does " desecration " mean? is it just flag burning — or does it also include smearing the flag with dirt? how about dropping it on the ground? and why should law enforcement get to decide who to arrest for such desecration? free expression and the right to dissent are among the core principles which the american flag represents. the first amendment must be protected most when it comes to unpopular speech. failure to do so fails the very notion of freedom of expression. our democracy is strong because we tolerate all peaceful forms of expression, no matter how uncomfortable they make us feel, or how much we disagree. if we take away the right to dissent - no matter how unpopular - what freedom will be sacrificed next? make a difference your support helps the aclu defend free speech and a broad range of civil liberties. burn the flag or burn the constitution? ( 2011 blog ) : sadly, congress is once again considering an amendment to the u. s. constitution banning desecration of the american flag and, in doing so, testing our political leaders ' willingness to defend what is arguably one of america ' s most sacred principles — protecting political speech. flag amendment defeated, first amendment stands unscathed ( 2003 ) : on june 27, 2006, the senate voted down the proposed flag desecration amendment by the slimmest margin ever. the vote was 66 - 34, just one vote short of the two - thirds needed to approve a constitutional amendment. reasons to oppose the flag desecration amendment ( 2004 resource ) : talking points on opposing the flag desecration amendment background on the flag desecration amendment ( 2004 resource ) fight for the flag - resources ( 2006 resource )


first, an object is placed on the platform of the printer upon – a petrie dish for example. then the printer must check the height of the object to make sure everything is calibrated correctly. mr. carvalho placed a paper card on the platform of the 3d - bioplotter to demonstrate how the machine works. mr. carvalho then talked us through the printing process. to begin, a liquefied material – in this case a silicone paste – is pressed through a needle - like tip by applying air pressure. the needle moves in all three dimensions which means it is able to create a three dimensional object. the printer is called ‘ bioplotter ’ because the unique aspect of this machine is its use of biomaterials to make implants or other objects for biomedical application. some of the implants which are made using the 3d bioplotter are intended to dissolve in the body. the materials which are used in this application include plla, plga, and silicone. implants made with thermoplastics – as they are mostly water and co2 – are removed by the body naturally in around a week or two. other materials, such as ceramic paste, may also be used to print implants. the implants printed using ceramic paste do not dissolve. instead, the body uses this material to create new bone. this actually speeds up the process of the body ’ s regeneration. the 3dbioplotter also prints hydrogels – such as collagen or alginate. these materials can have human cells actually added to them. thus human cells may be printed directly with this machine. every thursday is # 3dthursday here at adafruit! the diy 3d printing community has thrilled us at adafruit with its passion and dedication to making solid objects from digital models. recently, we have noticed that our community integrating electronics projects into 3d printed enclosures, brackets, and sculptures, so each thursday we celebrate and highlight these bold pioneers! have you take considered building a 3d project around an arduino or other microcontroller? how about printing a bracket to mount your raspberry pi to the back of your hd monitor? and don ’ t forget the countless el wire and led projects that are possible when you are modeling your projects! the adafruit learning system has dozens of great tools to get you well on your way to creating incredible works of engineering, interactive art, and design with your 3d printer! if you have a cool


re - inventing the planned city monday, march 12, 2012 tau and mit launch pilot project to re - think 50 ' s era " new towns " a bird ' s - eye view of kiryat gat in response to population growth, many " new towns " or planned cities were built around the world in the 1950s. but according to dr. tali hatuka, head of tel aviv university ' s laboratory for contemporary urban design ( lcud ) at the department of geography and the human environment, these cities are a poor fit for modern lifestyles — and it ' s time to innovate. tau has launched a pilot project, in collaboration with a team from the massachusetts institute of technology led by prof. eran ben - joseph, to revitalize this aging model. last month, a team of five tau and 11 mit graduate students visited kiryat gat, a mid - sized town in the south of israel. home to branches of industrial giants hewlett - packard company and intel, kiryat gat was chosen as a " laboratory " for re - designing outmoded planned civic spaces. based on smart technologies, improved transportation, use of the city ' s natural surroundings, and a reconsideration of the current use of city space, the team ' s action plan is designed to help kiryat gat emerge as a new, technologically - advanced planned city — a prototype that could be applied to similar urban communities. planning a future for the mid - sized city the project, jointly funded by tau ' s vice president for research and mit ' s misti global seed funds, will create a new planning model that could reshape the future of kiryat gat and similar cities across the world which are often overlooked in academia and practical planning. " our goal is to put a spotlight on these kinds of towns and suggest innovative ways of dealing with their problems, " says tau student roni bar. mit ' s alice shay, who visited israel for the first time for the project, believes that kiryat gat, a city that massive urbanization has left behind, is an ideal place for the team to make a change. " the city is at a catalyst point — an exciting moment where good governance and energy will give it the capacity to implement some of these new projects. " to tackle the design and planning challenges of the city, the team of students focused on four themes : the " mobile city, " which looked at transport and accessibility ; the " mediated city,


it the capacity to implement some of these new projects. " to tackle the design and planning challenges of the city, the team of students focused on four themes : the " mobile city, " which looked at transport and accessibility ; the " mediated city, " dealing with technological infrastructure ; the " compact city, " which reconsidered the use of urban space and population growth ; and the " natural city, " which integrated environmental features into the urban landscape. finding common ground ultimately, the team ’ s goal is to create a more flexible city model that encourages residents and workers to be a more active part of the urban fabric of the city, said dr. hatuka. the current arrangement of dedicated industrial, residential, and core zones is out of step with a 21st century lifestyle, in which people work, live, and spend their leisure time in the same environment. " much of the past discourse about the design of sustainable communities and ' eco - cities ' has been premised on using previously undeveloped land, " says prof. ben - joseph. " in contrast, this project focuses on the ' retrofitting ' of an existing environment — a more likely approach, given the extent of the world ' s already - built infrastructure. " the students from tau and mit have become a truly cohesive team, and their diversity of background helps challenge cultural preconceptions, bar says. " they ask many questions that help us to rethink things we took for granted. " shay agrees. " tali and eran have created an incredible collaboration, encouraging us all to exchange ideas. our contexts are different but there is a common urban design language. " the team estimates that they will be able to present the updated model of the city early next year. the next step is further exploring the project ' s key themes at a march meeting at mit. and while the project has provided an exceptional educational experience for all involved, ideas are already leaping off the page and into the city ' s urban fabric. " in the next two months, the mayor of kiryat gat would like to push this model forward and implement the initial steps that we have offered, " says an enthusiastic dr. hatuka.


elderly people are at increased risk of food - borne illness because as they age, their immune systems become weaker. in fact, the website for the centers for disease control estimates that each year about 48 million people get sick, 128, 000 are hospitalized and 3, 000 die from food - borne diseases. the most severe cases tend to occur in the very old. the good news is that food poisoning can be prevented if you follow proper home food safety practices. ruth frechman, a registered dietitian and spokesperson for the american dietetic association, spoke with agingcare. com about home food safety for elderly people. " since older adults are at particular risk for food - borne illness, good food safety habits are extremely crucial. " ms. frechman says three common cooking and food preparation mistakes can result in unsafe food and potential food poisoning. bacteria in raw meat and poultry juices can be spread to other foods, utensils and surfaces.. " to prevent cross - contamination, keep raw foods separate from ready - to - eat foods and fresh vegetables, " she says. " for example, use two cuttings boards : one strictly for raw meat, poultry and seafood ; the other for ready - to - eat foods like breads and vegetables. " she recommends washing cutting boards thoroughly in hot soapy water after each use or placing them in the dishwasher. use a bleach solution or other sanitizing solution and rinse with clean water. always wash your hands after handling raw meat. leaving food out too long leaving food out too long at room temperature can cause bacteria to grow to dangerous levels that can cause illness. " many people think it ' s okay to leave food sitting out for a few hours, " ms. frechman says. " but that ' s a dangerous habit. food should not be left out for more than two hours. and if it ' s over 90 degrees, like at an outdoor summer barbecue, food should not be out for more than one hour. " its common knowledge that meat should be cooked to proper temperatures. however, most people don ' t know that even leftovers that were previously cooked should be re - heated to a certain temperature. ms. frechman says re - heating foods to the proper temperature can kill many harmful bacteria. leftovers should be re - heated to at least 165 degrees fahrenheit. " harmful bacteria are destroyed when food is cooked to proper temperatures, " she says. " that ' s why a food thermometer comes in handy not


what is hiv? and what is aids? find answers to some common questions in this section. how is hiv transmitted - and how is it not transmitted? find out the answers in this section. worried you might have hiv? have an hiv test - it ' s the only way to know for sure. hiv treatment is not a cure, but it is keeping millions of people well. start learning about it in this section. in this section we have answered some of the questions you might have if you have just found out you have hiv. find healthcare services and support. a series of illustrated leaflets designed to support conversations between professionals and people with hiv. our award - winning series of patient information booklets. each title provides a comprehensive overview of one aspect of living with hiv. twice - monthly email newsletter on the practical aspects of delivering hiv treatment in resource - limited settings. our regular newsletter, providing in - depth discussion of the latest research across the hiv sector. free to people personally affected by hiv. find contact details for over 3000 key organisations in more than 190 countries an instant guide to hiv & aids in countries and regions around the world the most comprehensive listing of hiv - related services in the uk pre - exposure prophylaxis ( prep ) – free webinar 18 april 2013as part of its european hiv prevention work, nam is collaborating... learning the basics about hepatitis c 05 april 2013if you are familiar with nam ’ s patient information materials, hopefully you... treatment as prevention – free webinar 20 march 2013as part of its european hiv prevention work, nam is collaborating...


in preparation for christmas, i read stephen nissenbaum ' s 1998 " the battle for christmas, " a thorough exploration of this season. the book ' s title will be deceiving, because it has nothing to do with the recent sacred - vs. - secular christmas quarrels. nissenbaum explores the myriad ways that christmas has evolved in our nation. it turns out we ' ve been jockeying for more than 300 years over what this holiday means. in colonial america our faith - filled ancestors banned christmas altogether, outlawing it in some colonies. until the 1760s, one could not even find an almanac that would print the word " christmas " on the date dec. 25. this opposition was because christmas had become a drunken spectacle where gangs of poor young men roamed the streets, making merry and engaging in acts of petty rowdyism, vaguely like today ' s new year ' s eve. it was customary and permissible for these gangs to knock on doors of strangers to demand gifts. ( " so give us some figgy pudding.... " ) our nation ' s first " battle " for christmas was the movement to domesticate the holiday, a battle that nissenbaum suggests involved merchants, the middle and upper classes and the church. merchants began linking christmas and the purchase of manufactured gifts as early as the 1830s as society began to stress family celebrations in front of a tree and with santa visiting every home. in case you think that your complaining will reverse the commercialism of this holiday, according to nissenbaum that complaint first emerged in the 1830s. complain if you must, but don ' t expect results. nissenbaum so thoroughly explores clement moore ' s " ' twas the night before christmas " that one learns why saint nick touches the side of his nose and why his pipe is a short one. nissenbaum contends that the ascendance of santa claus, the emergence of the christmas tree and even the giving of gifts contribute to this gradual process of making christmas a less revolutionary, more predictable holiday. he explores dickens and scrooge, christmas parties for poor children and even the complicated master - slave relationship at christmas leading up to and immediately following the civil war. if you prefer to maintain that christmas was a pure season of private devotion and public worship until sears, roebuck, wal - mart and the supreme court got involved, don ' t read this book. ditto if you enjoy lamenting that " they ' ve taken christmas away from us, " nissenbaum might say that a


heal our planet earth secondary and universities educational outreach : secondary ( high ) schools and universities anthony marr from the hope foundation ’ s main point was the wild tigers. he believes that something must be done to keep these animals alive. " if we let this go, life will be less beautiful and worth less living, " anthony marr quoted. the money that he receives as a conservationist is donated to help out the endangered species. he makes many trips to india to help them find other solutions to their problems. if the people living in india keep living the way they ’ ve done, india will soon become a desert. changes need to be made and people need to adapt to these changes. i agree with anthony ’ s beliefs. even if tigers are bred, it does not make a difference, because they cannot survive on their own. no matter what humans do, it still will not change the fact that one of god ’ s creations is becoming destroyed. no animals should be killed for the purpose of human needs. it is not necessary to kill tigers to sell products and make money because of silly beliefs that of they eat this then something will happen. there are so many alternatives. humans need food, but they do not have to consume so much meat. every time they eat meat, a precious animal is being killed. animals do not kill us and eat us, then why should we do the same? more solutions need to be found and more people need to become more involved in saving the beauty of the world. go on to student - 10


science fair project encyclopedia the chloride ion is formed when the element chlorine picks up one electron to form the anion ( negatively charged ion ) cl−. the salts of hydrochloric acid hcl contain chloride ions and are also called chlorides. an example is table salt, which is sodium chloride with the chemical formula nacl. in water, it dissolves into na + and cl− ions. the word chloride can also refer to a chemical compound in which one or more chlorine atoms are covalently bonded in the molecule. this means that chlorides can be either inorganic or organic compounds. the simplest example of an inorganic covalently bonded chloride is hydrogen chloride, hcl. a simple example of an organic covalently bonded chloride is chloromethane ( ch3cl ), often called methyl chloride. other examples of inorganic covalently bonded chlorides which are used as reactants are : - phosphorus trichloride, phosphorus pentachloride, and thionyl chloride - all three are reactive chlorinating reagents which have been used in a laboratory. - disulfur dichloride ( scl2 ) - used for vulcanization of rubber. chloride ions have important physiological roles. for instance, in the central nervous system the inhibitory action of glycine and some of the action of gaba relies on the entry of cl− into specific neurons. the contents of this article is licensed from www. wikipedia. org under the gnu free documentation license. click here to see the transparent copy and copyright details


science fair project encyclopedia industrial design is an applied art whereby the aesthetics and usability of products may be improved. design aspects specified by the industrial designer may include the overall shape of the object, the location of details with respect to one another, colors, texture, sounds, and aspects concerning the use of the product ergonomics. additionally the industrial designer may specify aspects concerning the production process, choice of materials and the way the product is presented to the consumer at the point of sale. the use of industrial designers in a product development process may lead to added values by improved usability, lowered production costs and more appealing products. product design is focused on products only, while industrial design has a broader focus on concepts, products and processes. in addition to considering aesthetics, usability, and ergonomics, it can also encompass the engineering of objects, usefulness as well as usability, market placement, and other concerns. product design and industrial design can overlap into the fields of user interface design, information design and interaction design. various schools of industrial design and / or product design may specialize in one of these aspects, ranging from pure art colleges ( product styling ) to mixed programs of engineering and design, to related disciplines like exhibit design and interior design. in the us, the field of industrial design hit a high - water mark of popularity in the late 30 ' s and early 40 ' s, with several industrial designers becoming minor celebrities. raymond loewy, norman bel geddes, and henry dreyfuss remain the best known. in the uk, the term " industrial design " increasingly implies design with considerable engineering and technology awareness alongside human factors - a " total design " approach, promoted by the late stuart pugh ( university of strathclyde ) and others. famous industrial designers - egmont arens ( 1888 - 1966 ) - norman bel geddes ( 1893 - 1958 ) - henry dreyfuss ( 1904 - 1972 ) - charles and ray eames ( 1907 - 1978 ) and ( 1912 - 1988 ) - harley j. earl ( 1893 - 1969 ) - virgil exner ( 1909 - 1973 ) - buckminster fuller ( 1895 - 1983 ) - kenneth grange ( 1929 - ) - michael graves ( 1934 - ) - walter adolph gropius ( 1883 - 1969 ) - jonathan ive ( 1967 - ) - arne jacobsen ( 1902 - 1971 ) - raymond loewy ( 1893 - 1986 ) - ludwig mies van der rohe ( 1886 - 1969 ) - laszlo moholy -


dr. carl auer von welsbach ( 1858 - 1929 ) had a rare double talent of understanding how to pursue fundamental science and, at the same time, of commercializing himself successfully as a inventor and discoverer. he discovered 4 elements ( neodymium, praseodymium, ytterbium, and lutetium ). he invented the incandescent mantle, that helped gaslighting at the end of the 19th century to a renaissance. he developed the ferrocerium - it ` s still used as a flint in every disposable lighter. he was an eminent authority, and great expert in the field of rare earths ( lanthanoides ). he invented the electric metal filament light bulb which is used billions of times today. additionally, all his life he took active part in different fields, from photography to ornithology. his personal qualities are remembered highly by the people of althofen, he not only had an excellent mind but also a big heart. these qualities ensured him a prominent and lasting place not only in austria ` s science and industrial history. 9th of sept. 1858 : born in vienna, son of therese and alois ritter auer von welsbach ( his father was director of the imperial printing office the " staatsdruckerei " ). 1869 - 73 : went to the secondary school in mariahilf, ( then changed to the secondary school in josefstadt. ) 1873 - 77 : went to secondary school in josefstadt, graduation. 1877 - 78 : military service, became a second lieutenant. 1878 - 80 : inscribed into the technical university of vienna ; studies in math, general organic and inorganic chemistry, technical physics and thermodynamics with the professors winkler, bauer, reitlinger ; and pierre. 1880 - 82 : changed to the university of heidelberg ; lectures on inorganic experimental chemistry and lab. experiments with prof. bunsen, introduction to spectral analysis and the history of chemistry, mineralogy and physics. 5th of feb. 1882 : promotion to doctor of philosophy at the ruperta - carola - university in heidelberg. 1882 : return to vienna as unpaid assistant in prof. lieben ` s laboratory ; work with chemical separation methods for investigations on rare earth elements. 1882 - 1884 : publications : " ueber die erden des gadolinits von ytterby ", " ueber die seltenen erden ". 1885 : the first separation of the element " didymium " with help from a


- 1884 : publications : " ueber die erden des gadolinits von ytterby ", " ueber die seltenen erden ". 1885 : the first separation of the element " didymium " with help from a newly developed separation method from himself, based on the fractioned crystalisation of a didym - ammonium nitrat solution. after the characteristical colouring, auer gave the green components the name praseodymium, the pink components the name neodidymium. in time the latter element was more commonly known as neodymium. 1885 - 1892 : work on gas mantle for the incandescent lighting. development of a method to produce gas mantle ( " auerlicht ) based on the impregnation from cottontissue by means, measures, methods of liquids, that rare earth has been absolved in and the ash from the material in a following glow process. production of the first incandescent mantle out of lanthanum oxide, in which the gas flame is surrounded from a stocking ; definite improvement in light emmission, but lack of stability in humidity. continuous improvements in the chemical composition of the incandescent mantel " auerlicht ", experimentations of lanthanum oxide - magnesium oxide - variations. 18th of sept. 1885 : the patenting of a gas burner with a " actinophor " incandescent mantle made up of 60 % magnesium oxide, 20 % lanthanum oxide and 20 % yttrium oxide ; in the same year, the magnesium oxide part was replaced with zirconium oxide and the constitution of a second patent with reference to the additional use of the light body in a spirits flame. 9th of april 1886 : introduction the name " gasgluehlicht " through the journalist motiz szeps after the successful presentation from the actinophors in the lower austrian trade union ; regular production of the impregnation liquid, called " fluid ", at the chemical institute. 1887 : the acquisition of the factory wurth & co. for chemical - pharmaceutical products in atzgersdorf and the industrial production of the light bodies. 1889 : the beginning of sales problems because of the defaults with the earlier incandescent mantle, ie. it ` s fragility, the short length of use, as well as having an unpleasant, cold, green coloured light, and the relatively high price. the factory in atzgersdorf closes. the development of fraction


ethics of dementia research what are clinical trials and how are they controlled / governed? a clinical trial is a biomedical / health - related study into the effects on humans of a new medical treatment ( medicine / drug, medical device, vaccine or new therapy ), sometimes called an investigational medicinal product ( imp ). before a new drug is authorised and can be marketed, it must pass through several phases of development including trial phases in which its safety, efficacy, risks, optimal use and / or benefits are tested on human beings. existing drugs must also undergo clinical testing before they can be used to treat other conditions than that for which they were originally intended. organisations conducting clinical trials in the european union must, if they wish to obtain marketing authorisation, respect the requirements for the conduct of clinical trials. these can be found in the clinical trials directive ( “ directive 2001 / 20 / ec of the european parliament and of the council of 4 april 2001 on the approximation of the laws, regulations and administrative provisions of the member states relating to the implementation of good clinical practice in the conduct of clinical trials on medicinal products for human use ” ). there are also guidelines to ensure that clinical trials are carried out in accordance with good clinical practice. these are contained in the “ commission directive 2005 / 28 / ec of 8 april 2005 laying down principles and detailed guidelines for good clinical practice as regards investigational medicinal products for human use, as well as the requirements for authorisation of the manufacturing or importation of such products ” ( also known as the good clinical practice or gcp for short ). this document provides more concrete guidelines and lends further support to the clinical trials directive. the london - based european medicines agency ( ema ) has published additional, more specific guidelines which must also be respected. these include guidelines on inspection procedures and requirements related to quality, safety and efficacy. copies of the above - mentioned documents in 22 languages can be found at : http : / / ec. europa. eu / enterprise / pharmaceuticals / clinicaltrials / clinicaltrials _ en. htm the protection of people participating in clinical trials ( and in most cases in other types of research ) is further promoted by provisions of : - the european convention on human rights and biomedicine ( oviedo convention, act 2619 / 1998 ), - the additional protocol to the oviedo convention concerning biomedical research - the nuremberg code of 1949, - the revised helsinki declaration of the world medical association regarding ethical principles for medical research involving human subjects, - the belmont report of 18 april 1979


), - the additional protocol to the oviedo convention concerning biomedical research - the nuremberg code of 1949, - the revised helsinki declaration of the world medical association regarding ethical principles for medical research involving human subjects, - the belmont report of 18 april 1979 on the ethical principles and guidelines for the protection of human subjects of research. what are the different phases of trials? testing an experimental drug or medical procedure is usually an extremely lengthy process, sometimes lasting several years. the overall procedure is divided into a series of stages ( known as phases ) which are described below. clinical testing on humans can only begin after a pre - clinical phase, involving laboratory studies ( in vitro ) and tests on animals, which has shown that the experimental drug is considered safe and effective. whilst a certain amount of testing can be carried out by means of computer modelling and by isolating cells and tissue, it becomes necessary at some point in time to test the drug on a living creature. animal testing is an obligatory stage in the process of obtaining regulatory approval for new drugs and medicines, and hence a legal requirement ( eu directive 2001 / 83 / ec relating to medicinal products for human use ). the necessity of carrying out prior testing on animals is also stated in the world medical association ’ s “ ethical principles for medical research involving human subjects. in order to protect the well - being of research animals, researchers are guided by three principles which are called the 3rs : reduce the number of animals used to a minimum refine the way that experiments are carried out so that the effect on the animal is minimised and animal welfare is improved replace animal experiments with alternative ( non - animal ) techniques wherever possible. in addition, most countries will have official regulatory bodies which control animal research. most animals involved in research are mice. however, no animal is sufficiently similar to humans ( even genetically modified ones ) to make human testing unnecessary. for this reason, the experimental drug must also be tested on humans. the main phases of clinical trials clinical trials on humans can be divided into three main phases ( literally, phase i, ii and iii ). each phase has specific objectives ( please see below ) and the number of people involved increases as the trial progresses from one phase to the next. phase i trials phase 1 trials are usually the first step in testing a new drug or treatment on humans after successful laboratory and animal testing. they are usually quite small scale and usually involve healthy subjects or sub - groups of patients who share a particular characteristic. the aims of these trials are : - to assess the safety of experimental


new drug or treatment on humans after successful laboratory and animal testing. they are usually quite small scale and usually involve healthy subjects or sub - groups of patients who share a particular characteristic. the aims of these trials are : - to assess the safety of experimental drugs, - to evaluate any possible side effects, - to determine a safe dose range, - to see how the body reacts to the drug ( how it is absorbed, distributed and eliminated from the body, the effects that it has on the body and the effects it has on biomarkers ). dose ranging, sometimes called dose escalation, studies may be used as a means to determine the most appropriate dosage, but the doses administered to the subjects should only be a fraction of those which were found to cause harm to animals in the pre - clinical studies. the process of determining an optimal dose in phase i involves quite a high degree of risk because this is the first time that the experimental treatment or drug has been administered to humans. moreover, healthy people ’ s reactions to drugs may be different to those of the target patient group. for this reason, drugs which are considered to have a potentially high toxicity are usually tested on people from the target patient group. there are a few sequential approaches to phase i trials e. g. single ascending dose studies, multiple ascending dose studies and food effect. in single ascending dose studies ( sad ), a small group of subjects receive a very low dose of the experimental drug and are then observed in order to see whether that dose results in side effects. for this reason, trials are usually conducted in hospital settings. if no adverse side effects are observed, a second group of subjects are given a slightly higher dose of the same drug and also monitored for side - effects. this process is repeated until a dose is reached which results in intolerable side effects. this is defined as the maximum tolerated dose ( mtd ). multiple ascending dose studies ( mad ) are designed to test the pharmacokinetics and pharmacodynamics of multiple doses of the experimental drug. a group of subjects receives multiple doses of the drug, starting at the lowest dose and working up to a pre - determined level. at various times during the period of administration of the drug, and particularly whenever the dose is increased, samples of blood and other bodily fluids are taken. these samples are analysed in order to determine how the drug is processed within the body and how well it is tolerated by the body. food effect studies are investigations into the effect of food intake


, samples of blood and other bodily fluids are taken. these samples are analysed in order to determine how the drug is processed within the body and how well it is tolerated by the body. food effect studies are investigations into the effect of food intake on the absorption of the drug into the body. this involves two groups of subjects being given the same dose of the experimental drug but for one of the groups when fasting and for the other after a meal. alternatively, this could be done in a cross - over design whereby both groups receive the experimental drug in both conditions in sequence ( e. g. when fasting and on another occasion after a meal ). food effect studies allow researchers to see whether eating before the drug is given has any effect on the absorption of the drug by the body. phase ii trials having demonstrated the initial safety of the drug ( often on a relatively small sample of healthy individuals ), phase ii clinical trials can begin. phase ii studies are designed to explore the therapeutic efficacy of a treatment or drug in people who have the condition that the drug is intended to treat. they are sometimes called therapeutic exploratory trials and tend to be larger scale than phase i trials. phase ii trials can be divided into phase iia and phase iib although sometimes they are combined. phase iia is designed to assess dosing requirements i. e. how much of the drug should patients receive and up to what dose is considered safe? the safety assessments carried out in phase i can be repeated on a larger subject group. as more subjects are involved, some may experience side effects which none of the subjects in the phase i experienced. the researchers aim to find out more about safety, side effects and how to manage them. phase iib studies focus on the efficacy of the drug i. e. how well it works at the prescribed doses. researchers may also be interested in finding out which types of a specific disease or condition would be most suitable for treatment. phase ii trials can be randomised clinical trials which involve one group of subjects being given the experimental drug and others receiving a placebo and / or standard treatment. alternatively, they may be case series which means that the drug ’ s safety and efficacy is tested in a selected group of patients. if the researchers have adequately demonstrated that the experimental drug ( or device ) is effective against the condition for which it is being tested, they can proceed to phase iii. phase iii trials phase iii trials are the last stage before clinical approval for a new drug or device. by this stage, there will


drug ( or device ) is effective against the condition for which it is being tested, they can proceed to phase iii. phase iii trials phase iii trials are the last stage before clinical approval for a new drug or device. by this stage, there will be convincing evidence of the safety of the drug or device and its efficacy in treating people who have the condition for which it was developed. such studies are carried out on a much larger scale than for the two previous phases and are often multinational. several years may have passed since the original laboratory and animal testing. the main aims of phase iii trials are : to demonstrate that the treatment or drug is safe and effective for use in patients in the target group ( i. e. in people for whom it is intended ) to monitor side effects to test different doses or different ways of administering the drug to determine whether the drug could be used at different stages of the disease. to provide sufficient information as a basis for marketing approval researchers may also be interested in showing that the experimental drug works for additional groups of people with conditions other than that for which the drug was initially developed. for example, they may be interested in testing a drug for inflammation on people with alzheimer ’ s disease. the drug would have already have proven safe and obtained marketing approval but for a different condition, hence the need for additional clinical testing. open label extension trails open label extension studies are often carried out immediately after a double blind randomised clinical trial of an unlicensed drug. the aim of the extended study is to determine the safety and tolerability of the experimental drug over a longer period of time, which is generally longer than the initial trial and may extend up until the drug is licensed. participants all receive the experimental drug irrespective of which arm of the previous trial they were in. consequently, the study is no longer blind in that everybody knows that each participant is receiving the experimental drug but the participants and researchers still do not know which group participants were in during the initial trial. post - marketing surveillance studies ( phase iv ) after the three phases of clinical testing and after the treatment has been approved for marketing, there may be a fourth phase to study the long - term effects of drugs or treatment or to study the impact of another factor in combination with the treatment ( e. g. whether a particular drug reduces agitation ). usually, such trials are sponsored by pharmaceutical companies and described as pharmacovigilance. they are not as common as the other types of trials ( as they are not necessary for marketing permission ). however


whether a particular drug reduces agitation ). usually, such trials are sponsored by pharmaceutical companies and described as pharmacovigilance. they are not as common as the other types of trials ( as they are not necessary for marketing permission ). however, in some cases, the ema grants restricted or provisional marketing authorisation, which is dependent on additional phase iv trails being conducted. expanded access to a trial sometimes, a person might be likely to benefit from a drug which is at various stages of testing but does not fulfil the conditions necessary for participation in the trial ( e. g. s / he may have other health problems ). in such cases and if the person has a life - threatening or serious condition for which there is no effective treatment, s / he may benefit from “ expanded access ” use of the drug. there must, however, be evidence that the drug under investigation has some likelihood of being effective for that patient and that taking it would not constitute an unreasonable risk. the use of placebo and other forms of comparison the main purpose of clinical drug studies is to distinguish the effect of the trial drug from other influences such as spontaneous change in the course of the disease, placebo effect, or biased observation. a valid comparison must be made with a control. the american food and drugs administration recognises different types of control namely, - active treatment with a known effective therapy or - no treatment, - historical treatment ( which could be an adequately documented natural history of the disease or condition, or the results of active treatment in comparable patients or populations ). the ema considers three - armed trials ( including the experimental medicine, a placebo and an active control ) as a scientific gold standard and that there are multiple reasons to support their use in drug development. participants in clinical trials are usually divided into two or more groups. one group receives the active treatment with the experimental substance and the other group receives a placebo, a different drug or another intervention. the active treatment is expected to have a positive curative effect whereas the placebo is expected to have zero effect. with regard to the aim to develop more effective treatments, there are two possibilities : 1. the experimental substance is more effective than the current treatment or 2. it is more effective than no treatment at all. according to article 11 of the international ethical guidelines for biomedical research ( iegbr ) of 2002, participants allocated to the control group in a trial for a diagnostic, therapeutic or preventive intervention should receive an established effective intervention but it may in some circumstances be considered


article 11 of the international ethical guidelines for biomedical research ( iegbr ) of 2002, participants allocated to the control group in a trial for a diagnostic, therapeutic or preventive intervention should receive an established effective intervention but it may in some circumstances be considered ethically acceptable to use a placebo ( i. e. no treatment ). in article 11 of the iegbr, reasons for the use of placebo are : 1. that there is no established intervention 2. that withholding an established effective intervention would expose subjects to, at most, temporary discomfort or delay in relief of symptoms 3. that use of an established effective intervention as comparator would not yield scientifically reliable results and use of placebo would not add any risk of serious or irreversible harm to the subjects. november 2010, ema / 759784 / 2010 committee for medicinal products for human use the use of placebo and the issue of irreversible harm it has been suggested that clinical trials are only acceptable in ethical terms if there is uncertainty within the medical community as to which treatment is most suitable to cure or treat a disease ( national bioethics commission of greece, 2005 ). in the case of dementia, whilst there is no cure, there are a few drugs for the symptomatic treatment of dementia. consequently, one could ask whether it is ethical to deprive a group of participants of treatment which would have most likely improved their condition for the purpose of testing a potentially better drug ( national bioethics commission of greece, 2005 ). can they be expected to sacrifice their own best interests for those of other people in the future? it is also important to ask whether not taking an established effective intervention is likely to result in serious or irreversible harm. in the 2008 amended version of the helsinki declaration ( world medical association, 1964 ), the possible legitimate use of placebo and the need to protect subjects from harm are addressed. “ 32. the benefits, risks, burdens and effectiveness of a new intervention must be tested against those of the best current proven intervention, except in the following circumstances : the use of placebo, or no treatment, is acceptable in studies where no current proven intervention exists ; or where for compelling and scientifically sound methodological reasons the use of placebo is necessary to determine the efficacy or safety of an intervention and the patients who receive placebo or no treatment will not be subject to any risk of serious or irreversible harm. extreme care must be taken to avoid abuse of


use of placebo is necessary to determine the efficacy or safety of an intervention and the patients who receive placebo or no treatment will not be subject to any risk of serious or irreversible harm. extreme care must be taken to avoid abuse of this option. ” ( wma, 1964 with amendments up to 2008 ) the above is also quite similar to the position supported by the presidential commission for the study of bioethical issues ( pcsbi ) ( 2011 ). in its recently published report entitled “ moral science : protecting participants in human subjects research ”, the presidential commission argues largely in favour of a “ middle ground ” for ethical research, citing the work of emanuel and miller ( 2001 ) who state : “ a placebo - controlled trial can sometimes be considered ethical if certain methodological and ethical standards are met. it these standards cannot be met, then the use of placebos in a clinical trial is unethical. ” ( emanuel and miller, 2001 cited in pcsbi, 2011, p. 89 ). one of the standards mentioned is the condition that withholding proven effective treatment will not cause more than minimal harm. the importance of placebo groups for drug development the ethical necessity to include a placebo arm in a clinical trial may differ depending on the type of drug being developed and whether other comparable drugs exist. for example, a placebo arm would be absolutely necessary in the testing of a new compound for which no drug has yet been developed. this would be combined with comparative arms involving other alternative drugs which have already been proven effective. for studies involving the development of a drug based on an existing compound, a comparative trial would be necessary but not necessarily with a placebo arm, or at least with a smaller placebo arm nevertheless, the ema emphasises the value of placebo - controlled trials in the development of new medicinal products even in cases where a proven effective drug exists : “ forbiddingplacebo - controlled trials in therapeutic areas where there are proven, therapeutic methods would preclude obtaining reliable scientific evidence for the evaluation of new medicinal products, and be contrary to public health interest as there is a need for both new products and alternatives to existing medicinal products. ” ( ema, 2001 ). in 2001, concerns were raised about the interpretation of paragraph 29 of the 2000 version of the helsinki declaration in which prudence was called for in the use of placebo in research trials and it was advised that placebo should only be used in cases where there was no proven therapy for the condition under investigation. a document clarify


2000 version of the helsinki declaration in which prudence was called for in the use of placebo in research trials and it was advised that placebo should only be used in cases where there was no proven therapy for the condition under investigation. a document clarifying the position of the wma regarding the use of placebo was issued by the wma in 2001 in which it was made clear that the use of placebo might be ethically acceptable even if proven therapy was available. the current version of this statement is article 32 of the 2008 revised helsinki declaration ( quoted in sub - section 7. 2. 1 ). the pcsbi ( 2011 ) highlight the importance of ensuring that the design of clinical trials enables the researchers to resolve controversy and uncertainty over the merits of the trial drug and whether the trial drug is better than an existing drug if there is one. they suggest that studies which cannot resolve such questions or uncertainty are likely to be ignored by the scientific community and this would be unethical as it would mean that people had been unnecessarily exposed to risk without there being any social benefit. reasons for participation people with dementia who take part in clinical trials may do so for a variety of reasons. one possible reason is that they hope to receive some form of treatment that will improve their condition or even result in a cure. this is sometimes called the “ therapeutic misconception ”. in such cases, clinical trials may seem unethical in that advantage is being taken of the vulnerability of some of the participants. on the other hand, the possibility of participating in such a trial may help foster hope which may even enable a person to maintain their morale. a review of 61 studies on attitudes to trials has shed some light on why people participate in clinical trials ( edwards, lilford and hewison, 1998 ). in this review, it was found that over 60 % of participants in seven studies stated that they did or would participate in clinical trials for altruistic reasons. however, in 4 studies, over 70 % of people stated that they participated out of self - interest and in two studies over 50 % of people stated that they would participate in such a study out of self - interest. as far as informed consent is concerned, in two studies ( which were also part of this review ) 47 % of responding doctors thought that few patients were actually aware that they were taking part in a clinical trial. on the other hand, an audit of four further studies revealed that at least 80 % of participants felt that they had made an autonomous decision.