Population biology

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  • Conversely, modern biological sciences (including even concepts such as molecular ecology) are intimately entwined and dependent on the methods developed through biotechnology and what is commonly thought of as the life sciences industry.

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  • Bioinformatics is an interdisciplinary field which addresses biological problems using computational techniques, and makes the rapid organization and analysis of biological data possible. The field may also be referred to as computational biology, and can be defined as, "conceptualizing biology in terms of molecules and then applying informatics techniques to understand and organize the information associated with these molecules, on a large scale.

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  • It is hoped that the account given, in the following pages, of the lives of five great naturalists may not be found devoid of interest. The work of each one of them marked a definite advance in the science of Biology. There is often among students of anatomy and physiology a tendency to imagine that the facts with which they are now being made familiar have all been established by recent observation and experiment. But even the slight knowledge of the history of Biology, which may be obtained from a perusal of this little book, will show that, so far from such being the case,...

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  • The epidemiology of infectious diseases is one of the great triumphs of applied ecology. In particular, the public health importance of parasites has lead to a large literature, exploring their impact on the population dynamics, population genetics and evolutionary biology of human populations. An important milestone was the Dahlem Conference on population biology of infectious diseases, held in 1981. The resulting book (Anderson and May 1982) lucidly summarised the contemporary state of parasite ecology and epidemiology.

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  • The Biological Sciences Curriculum Study (BSCS) was established in 1958 with the mission to improve the quality of biology education at all levels. Not long after the inception of the organization, our mission was expanded to include the improvement of science education, not just biology education. In 2000, we further articulated this mission to describe the work we would do in curriculum develop- ment, professional development, and research and evaluation.

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  • Conserving biodiversity is a daunting and complex task. Perhaps no species presents a greater challenge than the giant panda – one of the most recognized and threatened animals on the planet. Its difficult-to-traverse, mountainous habitat in China makes quantifying population numbers in the wild exceedingly difficult. Despite a recent survey suggesting that the wild population may be growing, there is no disagreement that the primary threat is severely fragmented habitat.

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  • New Concepts in the Development of Cancer Therapeutics Cancer Stem Cells It has long been recognized that only a small proportion of the cells within a tumor are capable of initiating colonies in vitro or of forming tumors at high efficiency when injected into immunocompromised NOD/SCID mice. Current work indicates that human acute and chronic myeloid leukemias (AML and CML) have a small population of cells (

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  • Agriculture has been theorized to have become the dominant way of producing food since the Neolithic Revolution. Through early biotechnology, the earliest farmers selected and bred the best suited crops, having the highest yields, to produce enough food to support a growing population. As crops and fields became increasingly large and difficult to maintain, it was discovered that specific organisms and their by-products could effectively fertilize, restore nitrogen, and control pests.

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  • Other Hepatitis Viruses Hepatitis A virus is rarely transmitted by transfusion; infection is typically asymptomatic and does not lead to chronic disease. Other transfusion-transmitted viruses—TTV, SEN-V, and GBV-C—do not cause chronic hepatitis or other disease states. Routine testing does not appear to be warranted. West Nile Virus Transfusion-transmitted WNV infections were documented in 2002. This RNA virus can be detected using NAT; routine screening began in 2003, and more than 1000 blood donors have tested positive.

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  • In this edited volume, global experts in ecology and evolutionary biology explore how theories in ecology elucidate the processes of invasion, while also examining how specific invasions inform ecological theory. This reciprocal benefit is highlighted in a number of scales of organization: population, community and biogeographic. The text describes example invaders in all major groups of organisms and from a number of regions around the globe.

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  • Prevalence Data from the National Health and Nutrition Examination Surveys (NHANES) show that the percent of the American adult population with obesity (BMI 30) has increased from 14.5% (between 1976 and 1980) to 30.5% (between 1999 and 2000). As many as 64% of U.S. adults ≥20 years of age were overweight (defined as BMI 25) between the years of 1999 and 2000. Extreme obesity (BMI ≥40) has also increased and affects 4.7% of the population. The increasing prevalence of medically significant obesity raises great concern.

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  • Department of Genome Sciences, Life Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Rd, Berkeley, CA 94720, USA. †Department of Biology, University of Pennsylvania, 324 Leidy Laboratories, Philadelphia, PA 19104, USA. ‡Center for Integrative Genomics, Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA. §Current address: Department of Genetics, Washington University, 4566 Scott Ave, St. Louis, MO 63110, USA. Correspondence: Justin C Fay. E-mail: jfay@genetics.wustl.

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  • NOTICE: The project that is the subject of this report was approved by the Gov- erning Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engi- neering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for ap- propriate balance.

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  • Twenty years of regional population growth at almost 3 per cent per year has outpaced economic gains, leaving sub-Saharan Africans, on average, 22 per cent poorer than they were in the mid-1970s. The region’s progress is also hampered by large-scale migrations of people trying to escape poverty and political instability. Contributing to this migration is the large youth population, which fuels a rapid increase in new entrants to the labour market, and high fertility rates, outpacing the capacity of economies to generate a sufficient numbers of jobs.

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  • Chapter 19 - Variation and selection in populations. This chapter involves the study of how genetic laws impact the genetic makeup of a population. Mendelian principles are the basis for the Hardy-Weinberg law which allows one to calculate allele and genotype frequencies from one generation to the next. The Hardy-Weinberg law can be used only if other forces are not acting on the allele frequency. Those forces include selection, migration, mutation, and population size.

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  • *Institute of Cell, Animal and Population Biology, University of Edinburgh, Edinburgh, EH9 3JT, UK. †Department of Biological Sciences, Imperial College London, London SW7 2AZ, UK. ‡Current address: Program in Genetics and Genomic Biology, Hospital for Sick Children, University Avenue, Toronto, Ontario M5G 1X8, Canada. §Current address: Facultad de Química, Cátedra de Inmunología, Universita de la Republica, Montevideo 11300, Uruguay. Correspondence: Rick M Maizels. E-mail: rick.maizels@ed.ac.

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  • We used a PCR-based method to determine the genomic DNA sequences encoding phospholipases A2(PLA2s) from the venoms ofVipera aspis aspis(V. a. aspis),Vipera aspis zinnikeri (V. a. zinnikeri), Vipera berus berus(V. b. berus) and a neurotoxicV. a. aspissnake (neurotoxicV. a. aspis) from a population responsible for unusual neurotoxic envenomations in south-east France. We sequenced five groups of genes, each corresponding to a different PLA2.

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  • Chapter 23 - The evolution of populations. In this chapter, you should be able to: Explain why the majority of point mutations are harmless; explain how sexual recombination generates genetic variability; define the terms population, species, gene pool, relative fitness, and neutral variation; list the five conditions of Hardy-Weinberg equilibrium;...

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  • Chapter 52 - An introduction to ecology and the biosphere. In this chapter, you should be able to: Distinguish among the following types of ecology: organismal, population, community, ecosystem, and landscape; explain how dispersal may contribute to a species’ distribution; distinguish between the following pairs of terms: biotic and abiotic factors, macroclimate and microclimate patterns;...

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  • Chapter 53 - Population ecology. In this chapter, you should now be able to: Define and distinguish between the following sets of terms: density and dispersion; clumped dispersion, uniform dispersion, and random dispersion; life table and reproductive table; Type I, Type II, and Type III survivorship curves; semelparity and iteroparity; r-selected populations and K-selected populations. This chapter also explain how ecologists may estimate the density of a species, explain how limited resources and trade-offs may affect life histories,...

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