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This article presents a review on the existing techniques for manipulating biological cells. Because biomanipulation involves a wide range of disciplines, from biology to engineering, we concentrate on some of the key methodologies that would result in an efficient biomanipulation system. Some of the key methodologies discussed in this article for cell manipulation relate to the use of magnetics, microelectromechanical systems (MEMS)-based approaches, optics, electric field, and mechanical techniques. Recent advances in engineering have allowed researchers worldwide to address the problems arising from conventional manipulation techniques. This paper assimilates significance and limitations of biomanipulation techniques described in the literature. [ABSTRACT FROM AUTHOR]

We outline roles of frequency-dependent selection (FDS) in coadaptation and coevolutionary change. Coadaptation and coevolution occur because correlational selection (CS) and correlated evolution couple many traits. CS arises from causal interactions between traits expressed in two or more interactors, which invariably involve different traits (signalers-receivers). Thus, the causes of CS are due to FDS acting on trait interactions. Negative FDS, a rare advantage, is often coupled to positive FDS generating complex dynamics and FD cycles. Neural mechanisms of learning and perception create analogous mutes by which traits are reinforced in cognitive and perceptual systems of interactors, substituting for positive FDS. FDS across all levels of biological organization is thus best understood as proximate causes that link interactors and shape genetic correlations within and among interactors on long timescales, or cognitive trait correlations within interactors on short timescales. We find rock-paper-scissors dynamics are common in nature. [ABSTRACT FROM AUTHOR]

Electrophoretic separation of a mixture of chemical species is a fundamental technique of great usefulness in biology, health care, and forensics. In capillary electrophoresis (which has evolved from its predecessor, slab-gel electrophoresis), the sample migrates through a single microcapillary instead of through the network of pores in a gel. A fundamental design problem is to minimize dispersion in the separation direction. Molecular diffusion is inevitable and sets a theoretical limit on the best separation that can be achieved. But in practice, there are a number of effects arising out of the interplay between fluid flow, chemistry, thermal effects, and electric fields that result in enhanced dispersion. This paper reviews the subject of fluid flow in such capillary microchannels and examines the various causes of enhanced dispersion that limit the efficiency of separation. [ABSTRACT FROM AUTHOR]

About 20 years ago, DNA sequences were separately described from the quagga (a type of zebra) and an ancient Egyptian individual. What made these DNA sequences exceptional was that they were derived from 140- and 2400-year-old specimens. However, ancient DNA research, defined broadly as the retrieval of DNA sequences from museum specimens, archaeological finds, fossil remains, and other unusual sources of DNA, only really became feasible with the advent of techniques for the enzymatic amplification of specific DNA sequences. Today, reports of analyses of specimens hundreds, thousands, and even millions of years old are almost common-place. But can all these results be believed? In this paper, we critically assess the state of ancient DNA research. In particular, we discuss the precautions and criteria necessary to ascertain to the greatest extent possible that results represent authentic ancient DNA sequences. We also highlight some significant results and areas of promising future research. [ABSTRACT FROM AUTHOR]

Presents landmark events in the field of applied entomology and insect-related studies that have an impact on biology in general. Role of communication in entomology; Developments in the field of insect olfaction; Impact of technology in the study of applied entomology.

This article is a critique of the meaning and importance of some of the recently published work in the field whose development as a special area began with papers by Zuckerkandl & Pauling and Pauling & Zuckerkandl entitled Chemical Paleogenetics, Molecular Restoration Studies of Extinct Forms of Life and the paper by Margoliash on the evolution of cytochrome c. The primary emphasis is on conclusions and inferences derivable from amino acid sequences, followed bya section on nucleotide sequences. These are preceded by a brief indication of some of the literature that antedates the origin of the genetic code as it now stands. This will not treat immunoglobulin evolution, reviewed by Gally & Edelma and Smith, Hood & Fitch or related material on the evolution of enzymes and proteins reviewed by Smith and Arnheim. The functional interpretation of these changes has made significant progress [Dickerson and Takano et al]. For the evolution of metabolic pathways, see brew, Vogel, and Lejohn. [ABSTRACT FROM AUTHOR]

Spotted lanternfly, Lycorma delicatula (White), invaded the eastern United States in 2014 and has since caused economic and ecological disruption. In particular, spotted lanternfly has shown itself to be a significant pest of vineyards and ornamental plants and is likely to continue to spread to new areas. Factors that have contributed to its success as an invader include its wide host range and high mobility, which allow it to infest a wide range of habitats, including agricultural, urban, suburban, and managed and natural forested areas. Management is dependent on chemical use, although no single currently available control measure alone will be sufficient. [ABSTRACT FROM AUTHOR]

An enormous amount of work has been done on aging in Drosophila melanogaster, a classical genetic and molecular model system, but also in numerous other insects. However, these two extensive bodies of work remain poorly integrated to date. Studies in Drosophila often explore genetic, developmental, physiological, and nutrition-related aspects of aging in the lab, while studies in other insects often explore ecological, social, and somatic aspects of aging in both lab and natural populations. Alongside exciting genomic and molecular research advances in aging in Drosophila, many new studies have also been published on aging in various other insects, including studies on aging in natural populations of diverse species. However, no broad synthesis of these largely separate bodies of work has been attempted. In this review, we endeavor to synthesize these two semi-independent literatures to facilitate collaboration and foster the exchange of ideas and research tools. While lab studies of Drosophila have illuminated many fundamental aspects of senescence, the stunning diversity of aging patterns among insects, especially in the context of their rich ecology, remains vastlyunderstudied. Coupled with field studies and novel, more easily applicable molecular methods, this represents a major opportunity for deepening our understanding of the biology of aging in insects and beyond. [ABSTRACT FROM AUTHOR]

Relates the history of genetics in France. French biologists and genetics from 1900-1930; Explanation of the delayed development of genetics in France; Experimental and theoretical population genetics; Genetic control of eye pigmentation in Drosophila; Andre Lwoff's physiological evolution and theory of genetic continuity; Distinctiveness of French genetics.

Intraspecific predation, the process of both killing and eating an individual of the same species, is a significant and widespread process that until recently has not received the attention it merits. It is a major factor in the biology of many species and may influence population structure, life history, competition for mates and resources, and behavior. It is commonly observed among many animals: For this review I read over 900 papers describing such predation in about 1300 species. Laurel Fox's (1975 review of cannibalism (54) should be read for additional information. Here I attempt to present new or different data, references, and ideas. One of my purposes is to establish a theoretical framework for the organization and interpretation of the numerous observations of intraspecific predation. Certain topics included here are speculation intended to spark interest and indicate important problems that need further research. [ABSTRACT FROM AUTHOR]

In this paper I review the three best-known aspects of community structure in the deep-sea benthos: depth gradients of species diversity, spatial dispersion, and faunal replacement with depth. Patterns of species diversity are documented for the megafaunal invertebrates and fishes and four macrofaunal taxa (bivalves, gastropods, cumaceans, and polychaetes). These trends and data on spatial dispersion provide the basis for evaluating theories of species diversity in the deep sea. I then compare rates of species replacement with depth in megafaunal and macrofaunal elements, and relate differences between the groups to life-history parameters and trophic roles. [ABSTRACT FROM AUTHOR]

In this review, I address primarily the question whether the synthetic theory of population genetics, ecology and evolution supplies a sufficient explanation of what we find. The omission of a paper from the present bibliography is not intended as a criticism; for others, see the general review of Heliconius biology (23) and the comprehensive bibliographies (22, 105). There has always been a free exchange of data and ideas among Heliconius researchers, and some important discoveries and ideas have occurred simultaneously and independently; some foundation work is in unpublished theses (3, 22, 50, 51, 76, 85, 94). [ABSTRACT FROM AUTHOR]

Presents a tribute to Hermann Joseph Muller and his contributions to genetics. Profound interest in the properties of the genes as the initiator and organizer of life; Papers authored on the idea of the genes as the basis of life; Properties of the gene material drawing the grandiose picture of evolution by mutation.

Insects other than bees (i.e., non-bees) have been acknowledged as important crop pollinators, but our understanding of which crop plants they visit and how effective they are as crop pollinators is limited. To compare visitation and efficiency of crop-pollinating bees and non-bees at a global scale, we review the literature published from 1950 to 2018 concerning the visitors and pollinators of 105 global food crops that are known to benefit from animal pollinators. Of the 105 animal-pollinated crops, a significant proportion are visited by both bee and non-bee taxa (n = 82; 77%), with a total gross domestic product (GDP) value of US$780.8 billion. For crops with a narrower range of visitors, those that favor non-bees (n = 8) have a value of US$1.2 billion, compared to those that favor bees (n = 15), with a value of US$19.0 billion. Limited pollinator efficiency data were available for one or more taxa in only half of the crops (n = 61; 58%). Among the non-bees, some families were recorded visiting a wide range of crops (>12), including six families of flies (Syrphidae, Calliphoridae, Muscidae, Sarcophagidae, Tachinidae, and Bombyliidae), two beetle families (Coccinelidae and Nitidulidae), ants (Formicidae), wasps (Vespidae), and four families of moths and butterflies (Hesperiidae, Lycaenidae, Nymphalidae, and Pieridae). Among the non-bees, taxa within the dipteran families Syrphidae and Calliphoridae were the most common visitors to the most crops, but this may be an artifact of the limited data available. The diversity of species and life histories in these groups of lesser-known pollinators indicates that diet, larval requirements, and other reproductive needs will require alternative habitat management practices to bees. [ABSTRACT FROM AUTHOR]

The recent Ebola epidemic provides a dramatic example of the devastation and fear generated by epidemics, particularly those caused by new emerging or reemerging diseases. A focus on the control and prevention of diseases in living populations dominates most epidemic disease research. However, research on epidemics in the past provides a temporal depth to our understanding of the context and consequences of diseases and is crucial for predicting how diseases might shape human biology and demography in the future. This article reviews recent research on historic epidemics of plague and tuberculosis, both of which have affected human populations for millennia. Research on these diseases demonstrates the range (and differential availability) of various lines of evidence (e.g., burial context, diagnostic skeletal lesions, molecular data) that inform about past disease in general. I highlight how research on past epidemics may be informative in ways that benefit living populations. [ABSTRACT FROM AUTHOR]

Life expectancy has increased dramatically in the United States and in much of the world in recent years and decades. The factors underlying this increase are incompletely understood and are undoubtedly complex. A question that drives current research is whether life expectancy can be further extended using current knowledge of modifiable risk factors. A still more challenging research focus is on the possibility that life expectancy might be further increased through knowledge gained from studies of the basic biology of aging and its genetic and environmental modifiers. [ABSTRACT FROM AUTHOR]

A decade of structural genomics, the large-scale determination of protein structures, has generated a wealth of data and many important lessons for structural biology and for future large-scale projects. These lessons include a confirmation that it is possible to construct large-scale facilities that can determine the structures of a hundred or more proteins per year, that these structures can be of high quality, and that these structures can have an important impact. Technology development has played a critical role in structural genomics, the difficulties at each step of determining a structure of a particular protein can be quantified, and validation of technologies is nearly as important as the technologies themselves. Finally, rapid deposition of data in public databases has increased the impact and usefulness of the data and international cooperation has advanced the field and improved data sharing. [ABSTRACT FROM AUTHOR]

Over the past twenty years there have been great advances in light microscopy with the result that multidimensional imaging has driven a revolution in modern biology. The development of new approaches of data acquisition is reported frequently, and yet the significant data management and analysis challenges presented by these new complex datasets remain largely unsolved. As in the well-developed field of genome bioinformatics, central repositories are and will be key resources, but there is a critical need for informatics tools in individual laboratories to help manage, share, visualize, and analyze image data. In this article we present the recent efforts by the bioimage informatics community to tackle these challenges, and discuss our own vision for future development of bioimage informatics solutions. [ABSTRACT FROM AUTHOR]

Recent years have seen a rapid expansion in the scope of quantitative genetic analyses undertaken in wild populations. We illustrate here the potential for such studies to address fundamental evolutionary questions about the maintenance of genetic diversity and to reveal hidden genetic conflicts or constraints not apparent at the phenotypic level. Trade-offs between different components of fitness, sexually-antagonistic genetic effects, maternal effects, genotype-by-environment interactions, genotype-by-age interactions, and variation between different regions of the genome in localized genetic correlations may all prevent the erosion of genetic variance. We consider ways in which complex interactions between ecological conditions and the expression of genetic variation can be elucidated, and emphasize the benefits of conducting selection analyses within a quantitative genetic framework. We also review potential developments associated with rapid advances in genomic technology, in particular the increased availability of extensive marker information. Our conclusions highlight the complexity of processes contributing to the maintenance of genetic diversity in wild populations, and underline the value of a quantitative genetic approach in parameterizing models of life-history evolution. [ABSTRACT FROM AUTHOR]

Biological systems, from molecular complexes to whole organisms and ecological interactions, tend to have a modular organization. Modules are sets of traits that are internally integrated by interactions among traits, but are relatively independent from other modules. The interactions within modules rely on different mechanisms, depending on the context of a study. For morphological traits, modularity occurs in developmental, genetic, functional, and evolutionary contexts. A range of methods for quantifying integration and modularity in morphological data is available, and a number of comparative and experimental designs can be used to compare the different contexts. How development produces covariation between traits can have substantial implications for understanding genetic variation and the potential for evolutionary change, but research in this area has only begun and many questions remain unanswered. [ABSTRACT FROM AUTHOR]

This review presents several methods of determining complex chemical reaction mechanisms and their functions. One method is based on correlation functions of measured time series of concentrations of chemical species, another is on measurements of temporal responses of concentrations to various perturbations of arbitrary magnitude, the third deals with the analysis of oscillatory systems, and the fourth describes the use of genetic algorithms. All methods are applicable to chemical, biochemical, and biological reaction systems and to genetic networks. The methods depend on the design of appropriate experiments for the whole system and corresponding theories for interpretation that lead to information on the causal chemical connectivity of species, reaction pathways, reaction mechanisms, control centers in the system, and functions of the system. The first three methods require no assumption of a model or hypothesis, nor extensive calculations, unlike the interpretation of measurements made on a gene network at only one time. The methods offer advantageous approaches to systems biology. [ABSTRACT FROM AUTHOR]

The nuclear receptor PPAR3, is a ligand-activated transcription factor that plays an important role in the control of gene expression linked to a variety of physiological processes. PPAR3, was initially characterized as the master regulator for the development of adipose cells. Ligands for PPARγ include naturally occurring fatty acids and the thiazolidinedione (TZD) class of antidiabetic drugs. Activation of PPARγ improves insulin sensitivity in rodents and humans through a combination of metabolic actions, including partitioning of lipid stores and the regulation of metabolic and inflammatory mediators termed adipokines. PPARγ signaling has also been implicated in the control of cell proliferation, atherosclerosis, macrophage function, and immunity. Here, we review recent advances in our understanding of the diverse biological actions of PPARγ with an eye toward the expanding therapeutic potential of PPARγ agonist drugs. [ABSTRACT FROM AUTHOR]

Political science traditionally has either ignored biology in favor of purely environmental explanations for political phenomena or merely ruminated about the likely role of biology, leaving data-based research on biopolitics in dangerously short supply. Currently, attention to the apparent genetic basis for political and social orientations holds the greatest promise of advancing empirical biopolitics. Thus, in this essay, we orient behavior genetics research in the larger framework of biology and politics, confront its normative implications, describe the techniques involved, assess the strengths and weaknesses of commonly employed data and procedures, and describe the next steps in this research stream. Because these next steps involve molecular genetic work, we provide some background genetic information, but we mainly urge political scientists to join interdisciplinary teams so that nature and nurture can both be employed in ongoing efforts to understand the sources of mass-scale human politics. [ABSTRACT FROM AUTHOR]

Metabolic flux analysis (MFA) is a rapidly developing field concerned with the quantification and understanding of metabolism at the systems level. The application of MFA has produced detailed maps of flow through metabolic networks of a range of plant systems. These maps represent detailed metabolic phenotypes, contribute significantly to our understanding of metabolism in plants, and have led to the discovery of new metabolic routes. The presentation of thorough statistical evaluation with current flux maps has set a new standard for the quality of quantitative flux studies. In microbial systems, powerful methods have been developed for the reconstruction of metabolic networks from genomic and transcriptomic data, pathway analysis, and predictive modeling. This review brings together the recent developments in quantitative MFA and predictive modeling. The application of predictive tools to high quality flux maps in particular promises to be important in the rational metabolic engineering of plants. [ABSTRACT FROM AUTHOR]

Critics have debated for the past decade or more whether race is dead or alive in ‘the new genetics’: Is gertomics opening up novel terrains for social identities or is it reauthorizing race? I explore the relationship between race and the new genetics by considering whether this ‘race’ is the same scientific object as that produced by race science and whether these race-making practices are animated by similar social and political logics. I consider the styles of reasoning characteristic of the scientific work together with the economic and political rationalities of neo-Iiberalism, including identity politics as it meets biological citizenship. I seek to understand why and how group-based diversity emerges as an object of value‘something to be studied and specified, something to be fought for and embraced, and something that is profitable’in the networks that sustain the world of (post)genomics today. [ABSTRACT FROM AUTHOR]

This review aims to show how the new results from Çatalhöyük in central Turkey contribute to wider theories about the Neolithic in Anatolia and the Middle East. I argue that many of the themes found in symbolism and daily practice at Çatalhöyük occur very early in the processes of village formation and the domestication of plants and animals throughout the region. These themes include a social focus on memory construction; a symbolic focus on wild animals, violence, and death; and a central dominant role for humans in relation to the animal world. These themes occur early enough throughout the region that we can claim they are integral to the development of settled life and the domestication of plants and animals. Particularly the focus on time depth in house sequences may have been part of the suite of conditions, along with environmental and ecological factors, that ‘selected for’ sedentism and domestication. [ABSTRACT FROM AUTHOR]

With the completion of the Populus trichocarpa genome sequence and the development of various genetic genomic and biochemical tools, Populus now offers many possibilities to study questions that cannot be as easily addressed in Arabidopsis and rice, the two prime model systems of plant biology and genomics. Tree-specific traits such as wood formation, long-term perennial growth, and seasonality are obvious areas of research, but research in other areas such as control of flowering, biotic interactions, and evolution of adaptive traits is enriched by adding a tree to the suite of model systems. Furthermore, the reproductive biology of Populus (a dioeceous wind-pollinated long-lived tree) offers both new possibilities and challenges in the study and analysis of natural genetic and phenotypic variation. The relatively close phylogenetic relationship of Populus to Arabidopsis in the Furosid clads Eudicotyledonous plants aids in comparative functional studies on genome and gene family evolution in eudicots. [ABSTRACT FROM AUTHOR]

Arabinogalactan proteins is an umbrella term applied to a highly diverse class of cell surface glycoproteins, in any of which contain glycosylphosphatidylinositol lipid anchors. The structures of protein and glycan moieties of arabinogalactan proteins are overwhelmingly diverse while the "hydroxproline contiguity hypothesis" predicts arabinogalactan modification of members of many families of extracellular proteins. Descriptive studies using monoclonal antibodies reacting with carbohydrate epitopes on arabinogalactan proteins and experimental work using β-Yariv reagent implicate arabinogalactan proteins in many biological processes of cell proliferation and survival, pattern formation and growth, and in plant microbe interaction. Advanced structural understanding of arabinogalactan proteins and an emerging molecular genetic definition of biological roles of individual arabinogalactan protein species, in conjunction with potentially analogous extracellular matrix components of animals, stimulate hypotheses about their mode of action. Arabinogalactan proteins might be soluble signals, or might act as modulators and coreceptors of apoplastic morphogens; their amphiphilic molecular nature makes them prime candidates of mediators between the cell wall, the plasma membrane, and the cytoplasm. [ABSTRACT FROM AUTHOR]

Bioinformatics, the application of computational tools to the management and analysis of biological data, has stimulated rapid research advances in genomics through the development of data archives such as GenBank, and similar progress is just beginning within ecology. One reason for the belated adoption of informatics approaches in ecology is the breadth of ecologically pertinent data (from genes to the biosphere) and its highly heterogeneous nature. The variety of formats, logical structures, and sampling methods in ecology create significant challenges. Cultural barriers further impede progress, especially for the creation and adoption of data standards. Here we describe informatics frameworks for ecology, from subject-specific data warehouses, to generic data collections that use detailed metadata descriptions and formal ontologies to catalog and cross-reference information. Combining these approaches with automated data integration techniques and scientific workflow systems will maximize the value of data and open new frontiers for research in ecology. [ABSTRACT FROM AUTHOR]

Seaweed population biology has received far less attention than trophic dynamics, yet is critically important in establishing and maintaining algal communities. Complex life histories of habitat-forming kelps and fucoids, including spores, gametophytes, gametes, and microscopic and macroscopic benthic stages, must be considered within the context of their highly dynamic nearshore environments. We evaluate differences within and between kelps and fucoids in life histories as they affect population biology; dispersal and potential limitations in population establishment; macroscopic stages and variations in survival and longevity affecting stand structure; and microscopic stage responses to disturbance and variation in the physical environment. We suggest that the commonly made comparisons of seaweeds with terrestrial seed plants are misleading because of large differences in morphology, environments, and the ephemeral nature of propagule banks in the sea. We conclude that progress in understanding algal populations depends on better knowledge of microscopic stages and on feedback through density-dependent reproductive processes, dispersal and settlement. [ABSTRACT FROM AUTHOR]

The use of molecular approaches has become part of the standard of care in the management of pediatric cancer patients. Molecular approaches are now included in the initial diagnosis, definition of prognostically distinct patient subgroups, selection of patients for specific therapies, prediction of risk for toxicities to therapy, and monitoring of patients receiving both conventional and novel targeted therapies. This clinical application of molecular medicine has been based on a growing molecular understanding of cancer biology. Studies of pediatric cancers have contributed to this understanding in many ways. We present a model for understanding cancer biology, using specific examples taken from pediatric oncology, and then discuss the application of molecular techniques to the clinical management of pediatric cancer patients. [ABSTRACT FROM AUTHOR]

Mammalian fertilization requires the coordinated activity of motile spermatozoa, muscular contractions of the uterus and oviduct, as well as ciliary beating. These elastic structures generate forces that drive fluid motion, but their configurations are, in turn, determined by the fluid dynamics. We review the basic fluid mechanical aspects of reproduction, including flagellar/ciliary beating and peristalsis. We report on recent biological studies that have shed light on the relative importance of the mechanical ingredients of reproduction. In particular, we examine sperm motility in the reproductive tract, ovum pickup and transport in the oviduct, as well as sperm-egg interactions. We review recent advances in understanding the internal mechanics of cilia and flagella, flagellar surface interaction, sperm motility in complex fluids, and the role of fluid dynamics in embryo transfer. We outline promising computational fluid dynamics frameworks that may be used to investigate these complex, fluid-structure interactions. [ABSTRACT FROM AUTHOR]

The technological ability to alter biology, along with the social conditions and cultural expectations that enable such transformations, is spawning a variety of techniques that augment bodily forms and functions. These techniques, collectively known as enhancement technologies, aim to improve human characteristics, including appearance and mental or physical functioning, often beyond what is 'normal' or necessary for life and well-being. Humans have always modified their bodies. What distinguishes these techniques is that bodies and selves become the objects of improvement work, unlike previous efforts in modernity to achieve progress through social and political institutions. There are profound effects on sociality and subjectivity. This chapter reviews analytical approaches through which researchers have attempted to illuminate the practices, moral and economic reasoning, cultural assumptions and institutional contexts constituting enhancements, framing the discussion by examining the concept of the normal body. Examples from cosmetic, neurological and genetic enhancements will illustrate. [ABSTRACT FROM AUTHOR]

Astrobiology is the study of the living universe. Astronomy provides the context for the origin and evolution of life on Earth. Conversely, discoveries about the terrestrial biosphere--from extremophilic microbes to the evolution of intelligence-- inform our thinking about prospects for life elsewhere. Astrobiology includes the search for extraterrestrial life via in situ exploration, spectroscopy of solar and extrasolar planetary atmospheres, and the search for extraterrestrial intelligence. This review situates astrobiology within philosophical issues of the definition of life and the biological compatibility of the universe. It reviews the habitability of the Galaxy in general and of planets and moons in particular, and summarizes current controversies in origins-of-life research and in evidence for the earliest life on Earth. It critiques certain "rare Earth" and "anthropic" arguments, and considers four approaches to deciding whether intelligent life exists elsewhere in the Galaxy. It concludes that astrobiology must also speak to the future of human civilization. [ABSTRACT FROM AUTHOR]

The central highlands of Mexico are considered to be a center of genetic diversity for both the potato late blight pathogen and for tuber-bearing Solanum spp. Recent work conducted in Mexico and South America sheds new light on the biology and evolution of Phytophthora infestans and other related Phytophthora pathogens. It now appears that Mexican Solanum species, which coevolved with P. infestans and were previously known for providing a source of R-genes, also provide a source of quantitative, rate-reducing resistance that is highly effective, stable, and durable. It is now apparent that Mexico is the center of origin not only of the potato late blight pathogen P. infestans,but also of several related Phytophthora species including P. mirabilis, P. ipomoeae, and possibly P. phaseoli. We close with the hypothesis that these Phytophthora species evolved sympatrically from one ancestral host through adaptive radiation onto their respective four host families. [ABSTRACT FROM AUTHOR]

The Rhabdoviridae, whose members collectively infect invertebrates, animals, and plants, form a large family that has important consequences for human health, agriculture, and wildlife ecology. Plant rhabdoviruses can be separated into the genera Cytorhabdovirus and Nucleorhabdovirus, based on their sites of replication and morphogenesis. This review presents a general overview of classical and contemporary findings about rhabdovirus ecology, pathology, vector relations, and taxonomy. The genome organization and structure of several recently sequenced nucleorhabdoviruses and cytorhabdoviruses is integrated with new cell biology findings to provide a model for the replication of the two genera. A prospectus outlines the exciting opportunities for future research that will contribute to a more detailed understanding of the biology, biochemistry, replication and host interactions of the plant rhabdoviruses. [ABSTRACT FROM AUTHOR]

Although well known as the location of the mechanism by which the cardiac sarcomere is activated by Ca2+ to generate force and shortening, the thin filament is now also recognized as a vital component determining the dynamics of contraction and relaxation. Molecular signaling in the thin filament involves steric, allosteric, and cooperative mechanisms that are modified by protein phosphorylation, sarcomere length and load, the chemical environment, and isoform composition. Approaches employing transgenesis and mutagenesis now permit investigation of these processes at the level of the systems biology of the heart. These studies reveal that the thin filaments are not merely slaves to the levels of Ca2+ determined by membrane channels, transporters and exchangers, but are actively involved in beat to beat control of cardiac function by neural and hormonal factors and by the Frank-Starling mechanism. [ABSTRACT FROM AUTHOR]

Although the use of aggregation pheromones has been reported for hundreds of nonsocial arthropod species, the evolutionary ecological aspects of this behavior have received little attention. Despite the elaborate literature on mechanisms, robust data on costs and benefits of aggregation pheromones are scant. Existing literature indicates that, in contrast to the diversity of mechanisms, the ecological conditions in which aggregation pheromones are used are more alike. This points to a few general categories for costs and benefits of aggregation pheromones, and these are discussed. We subsequently review interspecific interactions that may be affected by the use of aggregation pheromones. We encounter a strikingly frequent association of aggregation pheromones with fungi and microorganisms and address cross-attraction by competitor species and exploitation by natural enemies. We show that aggregative behavior by individuals through the use of pheromones can profoundly affect ecological interactions and advocate further evolutionary and ecological investigations of pheromone-mediated aggregation. [ABSTRACT FROM AUTHOR]

The Bactrocera dorsalis complex of tropical fruit flies (Diptera: Tephritidae: Dacinae) contains 75 described species, largely endemic to Southeast Asia. Within the complex are a small number of polyphagous pests of international significance, including B. dorsalis sensu stricto, B. papayae, B. carambolae, and B. philippinensis. Most species within the complex were described in 1994 and since then substantial research has been undertaken in developing morphological and molecular diagnostic techniques for their recognition. Such techniques can now resolve most taxa adequately. Genetic evidence suggests that the complex has evolved in only the last few million years, and development of a phylogeny of the group is considered a high priority to provide a framework for future evolutionary and ecological studies. As model systems, mating studies on B. dorsalis s.s. and B. cacuminata have substantially advanced our understanding of insect use of plant-derived chemicals for mating, but such studies have not been applied to help resolve the limits of biological species within the complex. Although they are commonly regarded as major pests, there is little published evidence documenting economic losses caused by flies of the B. dorsalis complex. Quantification of economic losses caused by B. dorsalis complex species is urgently needed to prioritize research for quarantine and management. Although they have been documented as invaders, relatively little work has been done on the invasion biology of the complex and this is an area warranting further work. [ABSTRACT FROM AUTHOR]

Just as nucleic acids can carry out enzymatic reactions, proteins can be genes. These heritable infectious proteins (prions) follow unique genetic rules that enable their identification: reversible curing, inducible "spontaneous generation," and phenotype surprises. Most prions are based on self-propagating amyloids, depend heavily on chaperones, show strain phenomena and, like other infectious elements, showspecies barriers to transmission. A recently identified prion is based on obligatory self-activation of an enzyme in trans. Although prions can be detrimental, they may also be beneficial to their hosts. [ABSTRACT FROM AUTHOR]

Tobacco mosaic virus (TMV) has had an illustrious history for more than 100 years, dating to Beijerinck's description of the mosaic disease of tobacco as a contagium vivum fluidum and the modern usage of the word "virus." Since then, TMV has been acknowledged as a preferred didactic model and a symbolic model to illuminate the essential features that define a virus. TMV additionally emerged as a prototypic model to investigate the biology of host plants, namely tobacco. TMV also exemplifies how a model system furthers novel, and often unexpected, developments in biology and virology. Today, TMV is used as a tool to study host-pathogen interactions and cellular trafficking, and as a technology to express valuable pharmaceutical proteins in tobacco. The history of TMV illustrates how pragmatic strategies to control an economically important disease of tobacco have had unexpected and transforming effects across platforms that impinge on plant health and public health. [ABSTRACT FROM AUTHOR]

This article presents the experiences of a woman in academic plant pathology from the 1950s to today. Topics include the social climate for women in science, personal and professional developments and research discoveries, public policy issues in agriculture and biotechnology affecting plant pathology, and projections for the future of plant pathology. [ABSTRACT FROM AUTHOR]

Modeling and simulation are becoming increasingly accepted components of materials research. In this review we discuss application of modeling and simulation in the developing field of biomaterials. To restrict the discussion somewhat, we focus primarily on the structure and properties of biomaterials and do not discuss biochemical or biomedical applications. We start with a discussion of how atomistic-level simulation can be used to study molecules and collections of molecules. We then focus on mesoscale simulations of structure and properties, followed by a brief review of continuum-scale approaches. We end with some thoughts on the future of modeling and simulation in biomaterials applications. [ABSTRACT FROM AUTHOR]

I had the good luck to start research at the dawn of molecular biology when it was possible to ask fundamental questions about the nature of the nucleic acids and how information is transferred in living systems. The search for answers led me into many different areas, often with the question of how molecular structure leads to biological function. Early work in this period provided some of the roots supporting the current explosive developments in life sciences. Here I give a brief account of my development, describe some contributions, and provide a hint of the exhilaration in discovering new things. Most of all, I had the good fortune to have inspiring teachers, stimulating colleagues, and excellent students. [ABSTRACT FROM AUTHOR]

Debate on the validity and reliability of scientific methods often arises in the courtroom. When the government (i.e., the prosecution) is the proponent of evidence, the defense is obliged to challenge its admissibility. Regardless, those who seek to use DNA typing methodologies to analyze forensic biological evidence have a responsibility to understand the technology and its applications so a proper foundation(s) for its use can be laid. Mitochondrial DNA (mtDNA), an extranuclear genome, has certain features that make it desirable for forensics, namely, high copy number, lack of recombination, and matrilineal inheritance. mtDNA typing has become routine in forensic biology and is used to analyze old bones, teeth, hair shafts, and other biological samples where nuclear DNA content is low. To evaluate results obtained by sequencing the two hypervariable regions of the control region of the human mtDNA genome, one must consider the genetically related issues of nomenclature, reference population databases, heteroplasmy, paternal leakage, recombination, and, of course, interpretation of results. We describe the approaches, the impact some issues may have on interpretation of mtDNA analyses, and some issues raised in the courtroom. [ABSTRACT FROM AUTHOR]

Given the unique biological requirements of sound transduction and the selective advantage conferred upon a species capable of sensitive sound detection, it is not surprising that up to 1% of the approximately 30,000 or more human genes are necessary for hearing. There are hundreds of monogenic disorders for which hearing loss is one manifestation of a syndrome or the only disorder and therefore is non-syndromic. Herein we review the supporting evidence for identifying over 30 genes for dominantly and recessively inherited, nonsyndromic, sensorineural deafness. The state of knowledge concerning their biological roles is discussed in the context of the controversies within an evolving understanding of the intricate molecular machinery of the inner ear. [ABSTRACT FROM AUTHOR]

A childhood fascination with animals, plants, and insects was aided and abetted by many giants, beginning with my parents. The Bronx High School of Science and the City College of New York (CCNY) made a solid and priceless grounding in chemistry and biology available free of charge. Abe Mazur at CCNY revealed the wonders of biochemistry and illustrated that it was possible to pursue these wonders while being paid to do so. He also directed me to Duke University Medical School for PhD work under the tutelage of Phil Handler. With the exception of a sabbatical year at Harvard with Frank Westheimer, my entire career has been spent at Duke serving under three fine and supportive chairmen: Handler, Hill, and Raetz. The premier discoveries to emanate from my laboratory have been the sulfite oxidase, the several superoxide dismutases, the manganese catalase, and the catalase/ peroxidase. Many other topics piqued my interest and resulted in ∼400 publications. Herein I have recounted some of the circumstances surrounding that work and named a few of the people involved. The first 20 years I worked happily at the bench and the next 35 years just as happily facilitating the work of younger people. It has been so rewarding that I wish for nothing more than to be allowed to keep at it. [ABSTRACT FROM AUTHOR]

This chapter summarizes some of the conceptual changes in developmental research over the last half-century. These advances include an acknowledgment of the role of maturation; also recognized have been the need for positing distinct psychological structures, the influence of temperament, the malleability of the infant, the role of the local context, and the dynamic nature of the categories describing human psychological types. [ABSTRACT FROM AUTHOR]

Describes quasicontinuum representations of atomic-scale mechanics. Universality and specificity in materials science and biology; Degree of freedom thinning and effective theory construction; Ideas for a constrained representation of amino acids.

Focuses on the impact of intestinal helminthiasis on human nutrition throughout the life cycle. Biology of intestinal helminths; Models of human and animal biology; Evidence of helminth-induced nutritional impairment.