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Selected AbstractsDoes the Emergency Exception from Informed Consent Process Protect Research Subjects?ACADEMIC EMERGENCY MEDICINE, Issue 11 2005Nicole M. Delorio MD Abstract Although subject protection is the cornerstone of medical ethics, when considered in the context of research using emergency exception from informed consent, its success is debatable. The participants of a breakout session at the 2005 Academic Emergency Medicine Consensus Conference discussed the issues surrounding subject protection and advanced the following recommendations. 1) There are no outcome measures that define "protection"; therefore, it is not currently known whether or not subjects are protected under the current rules. 2) Care must be taken to protect not only the individual from harm during research but also to protect society from unregulated research in other countries and an inability to appropriately advance medical knowledge. 3) Some surrogate markers/methods of protection whose efficacies are debatable include data safety monitoring board activity, the community consultation and public notification (CC/PN) process, and institutional review board approval. 4) Minimal-risk studies should be held to different standards of protection than those that involve more significant risk to the subject. 5) A handful of studies have been published regarding community consultation and notification, and the majority are case studies. Those that are specifically designed to discover the most successful methods are hindered by a lack of formal outcomes measures and tend to have negative results. 6) Follow-up data from the CC/PN process should be disclosed to the Food and Drug Administration and incorporated into study designs. 7) Focus groups and/or random-digit dialing have been suggested as promising methods for fulfilling the CC/PN requirements. 8) Studies need to be funded and performed that formally investigate the best means of CC/PN. 9) More funding for this research should be a priority in the emergency medicine and critical care communities. More data regarding terminated studies should be made available to the research community. 10) Quantifiable markers of success for CC/PN must be validated so that research may determine the most successful methods. 11) Data regarding subjects' and family members' experiences with exception from informed consent studies need to be obtained. [source] The silver spoon effect and habitat selection by natal dispersersECOLOGY LETTERS, Issue 11 2006Judy A. Stamps Abstract The silver spoon effect in the context of habitat selection occurs when dispersers in good condition are more likely to settle in high-quality habitats than dispersers in poor condition. Positive relationships between disperser condition and the quality of post-dispersal habitats are predicted by at least two non-exclusive ultimate hypotheses. The competition hypothesis assumes that a disperser's condition affects its chances of competing for space or joining an established group after arriving at a high-quality habitat, while the search hypothesis assumes that a disperser's condition affects its selectivity, and hence its chances of accepting a lower-quality habitat when it is searching for a new habitat. Thus far, silver spoon effects in the context of habitat selection have been reported in only a handful of species (several birds and marine invertebrates), but this study suggests that they may be relatively common in particular species and situations. [source] The ecology of restoration: historical links, emerging issues and unexplored realmsECOLOGY LETTERS, Issue 6 2005T. P. Young Abstract Restoration ecology is a young academic field, but one with enough history to judge it against past and current expectations of the science's potential. The practice of ecological restoration has been identified as providing ideal experimental settings for tests of ecological theory; restoration was to be the ,acid test' of our ecological understanding. Over the past decade, restoration science has gained a strong academic foothold, addressing problems faced by restoration practitioners, bringing new focus to existing ecological theory and fostering a handful of novel ecological ideas. In particular, recent advances in plant community ecology have been strongly linked with issues in ecological restoration. Evolving models of succession, assembly and state-transition are at the heart of both community ecology and ecological restoration. Recent research on seed and recruitment limitation, soil processes, and diversity,function relationships also share strong links to restoration. Further opportunities may lie ahead in the ecology of plant ontogeny, and on the effects of contingency, such as year effects and priority effects. Ecology may inform current restoration practice, but there is considerable room for greater integration between academic scientists and restoration practitioners. [source] Emergency medicine in India: Why are we unable to ,walk the talk'?EMERGENCY MEDICINE AUSTRALASIA, Issue 4 2007Suresh S David Abstract The largest democracy on earth, the second most populous country and one of the most progressive countries in the globe, India, has advanced tremendously in most conventional fields of Medicine. However, emergency medicine (EM) is a nascent specialty and is yet to receive an identity. Today, it is mostly practised by inadequately trained clinicians in poorly equipped emergency departments (EDs), with no networking. Multiple factors such as the size of the population, variation in standards of medical education, lack of pre-hospital medical systems and non-availability of health insurance schemes are some of the salient causes for this tardy response. The Indian medical system is governed by a central, regulatory body which is responsible for the introduction and monitoring of all specialties , the Medical Council of India (MCI). This organisation has not recognized EM as a distinct specialty, despite a decade of dogged attempts. Bright young clinicians who once demonstrated a keen interest in EM have eventually migrated to other conventional branches of medicine, due to the lack of MCI recognition and the lack of specialty status. The Government of India has launched a nationwide network of transport vehicles and first aid stations along the national highways to expedite the transfer of patients from a crash site. However, this system cannot be expected to decrease morbidity and mortality, unless there is a concurrent development of EDs. The present article intends to highlight factors that continue to challenge the handful of dedicated, full time emergency physicians who have tenaciously pursued the cause for the past decade. A three-pronged synchronous development strategy is recommended: (i) recognise the specialty of EM as a distinct and independent basic specialty; (ii) initiate postgraduate training in EM, thus enabling EDs in all hospitals to be staffed by trained Emergency physicians; and (iii) ensure that EMs are staffed by trained ambulance officers. The time is ripe for a paradigm shift, since the country is aware that emergency care is the felt need of the hour and it is the right of the citizen. [source] Differential impact of state tobacco control policies among race and ethnic groupsADDICTION, Issue 2007John A. Tauras ABSTRACT Aims This paper describes patterns of racial and ethnic cigarette use in the United States and discusses changes in state-level tobacco control policies. Moreover, this paper reviews the existing econometric literature on racial and ethnic smoking and discusses the limitations of that research. Finally, this paper outlines an agenda for future research. Methods Patterns of racial and ethnic smoking and changes in state-level tobacco control policies in the United States were obtained from a variety of sources, including surveys and government and private documents and databases. After an extensive literature search was completed, the existing research was scrutinized and recommendations for much-needed future research were put forth. Findings Despite the fact that certain racial and ethnic minorities bear a disproportionate share of the overall health burden of tobacco, less than a handful of econometric studies have examined the effects of state-level public policies on racial and ethnic smoking. The existing literature finds Hispanics and African Americans to be more responsive to changes in cigarette prices than whites. Only one study examined other state-level tobacco policies. The findings from that study implied that adolescent white male smoking was responsive to changes in smoke-free air laws, while adolescent black smoking was responsive to changes in youth access laws. Conclusions While much has been learned from prior econometric studies on racial and ethnic smoking in the United States, the existing literature suffers from numerous limitations that should be addressed in future research. Additional research that focuses on races and ethnicities other than white, black and Hispanic is warranted. Furthermore, future studies should use more recent data, hold sentiment toward tobacco constant and control for a comprehensive set of tobacco policies that take into account not only the presence of the laws, but also the level of restrictiveness of each policy. [source] Size-Related Advantages for Reproduction in a Slightly Dimorphic Raptor: Opposite Trends between the SexesETHOLOGY, Issue 12 2007Fabrizio Sergio Despite many comparative analyses and more than 20 proposed hypotheses, there is still little consensus over the factors promoting the evolution of reversed sexual dimorphism (RSD) in raptorial species. Furthermore, intrapopulation studies, which may elucidate how RSD is maintained once evolved, have been surprisingly scarce and only focused on a handful of species with medium to high dimorphism. We examined the reproductive advantages associated with body size and condition, measured in the pre-laying period, in a diurnal raptor with low sexual dimorphism, the black kite (Milvus migrans). The study population was essentially monomorphic in size. For females, there was an evidence of reproductive benefits associated with larger size and/or with better body condition. Larger females had also access to higher quality partners and territories, consistent with the ,intrasexual selection' hypothesis, by which members of the larger sex enjoy size-related advantages in intrasexual competition over a scarce resource, the smaller sex. Opposite trends emerged for males: smaller, leaner males had higher breeding output, consistent with the ,small efficient male' hypothesis. Overall, the fact that we observed in an essentially monomorphic population the same selection pressures previously found in species with marked dimorphism suggests that such reproductive advantages may be counterbalanced in our study model by opposite selection pressures during other stages of the life cycle. This casts some doubts on the evolutionary significance of studies focusing exclusively on reproduction and calls for the need of more comprehensive analyses incorporating trait-mediated differentials in survival and recruitment. [source] Increased Concentration in Banking: Megabanks and Their Implications for Deposit InsuranceFINANCIAL MARKETS, INSTITUTIONS & INSTRUMENTS, Issue 1 2005Kenneth D. Jones During the past two decades, the U.S. banking industry has experienced an unprecedented wave of consolidation, marked by a substantial decline in the number of insured depository institutions and the emergence of banking behemoths with assets totaling in the hundreds of billions of dollars. This unparalleled concentration of assets and deposits among a handful of "megabanks" has important implications for deposit insurance. Most importantly, the Federal Deposit Insurance Corporation (FDIC) now faces a situation in which the failure of even a single megabank could overwhelm the resources immediately available to the deposit insurance system and expose both the banking industry and the government (i.e., taxpayers) to huge potential liabilities. This article highlights the current structure of the banking industry, examines the threat that this structure poses to the deposit insurance funds, and suggests possible approaches for dealing with megabanks and the increasing concentration of insured deposits. [source] Effects of Phonon Confinement on Anomalous Thermalization, Energy Transfer, and Upconversion in Ln3+ -Doped Gd2O3 NanotubesADVANCED FUNCTIONAL MATERIALS, Issue 4 2010Andreia G. Macedo Abstract There is a growing interest in understanding how size-dependent quantum confinement affects the photoluminescence efficiency, excited-state dynamics, energy-transfer and thermalization phenomena in nanophosphors. For lanthanide (Ln3+)-doped nanocrystals, despite the localized 4f states, confinement effects are induced mostly via electron,phonon interactions. In particular, the anomalous thermalization reported so far for a handful of Ln3+ -doped nanocrystals has been rationalized by the absence of low-frequency phonon modes. This nanoconfinement may further impact on the Ln3+ luminescence dynamics, such as phonon-assisted energy transfer or upconversion processes. Here, intriguing and unprecedented anomalous thermalization in Gd2O3:Eu3+ and Gd2O3:Yb3+,Er3+ nanotubes, exhibiting up to one order of magnitude larger than previously reported for similar materials, is reported. This anomalous thermalization induces unexpected energy transfer from Eu3+C2 to S6 crystallographic sites, at 11,K, and 2H11/2,,,4I15/2 Er3+ upconversion emission; it is interpreted on the basis of the discretization of the phonon density of states, easily tuned by varying the annealing temperature (923,1123,K) in the synthesis procedure, and/or the Ln3+ concentration (0.16,6.60%). [source] Crawfish Tails: A Curious Tale of Foreign Trade Policy MakingFOREIGN POLICY ANALYSIS, Issue 2 2007CAMERON G. THIES This paper presents a case study of the demand for and supply of protectionism upon exposure to international trade. The examination of the crawfish industry demonstrates that theories of the demand for protectionism often provide inadequate or incomplete explanations of outcomes. The curious aspect of this case is that crawfish producers failed to organize to demand protection despite having many factors working in their favor. In fact, political representatives at the state level organized demand from federal agencies on their behalf, thus supplying protection without any real organized demand. In the end, only a handful of crawfish processors (not producers) received any benefits from protection, and Chinese imports still dominate the U.S. crawfish market. The result is consistent with the notion that the U.S. system of trade regulation is designed to produce the appearance, but not the substance of protection in order to uphold general principles of freer trade while making elected officials look responsive to their constituents. [source] Feature: UNESCO World Heritage and the Joggins cliffs of Nova ScotiaGEOLOGY TODAY, Issue 4 2004Howard J. Falcon-Lang UNESCO World Heritage status is the highest honour that may be bestowed on a palaeontological site. In addition to heightening conservation status, it confers international recognition of a locality's ,outstanding universal value' and often triggers the release of substantial regional development funds. Despite these incentives it is, perhaps, not surprising that only a handful of fossil sites have successfully navigated the World Heritage selection process. In this feature, we draw on our recent experience of developing a World Heritage bid for the Pennsylvanian ,Coal Age' locality of Joggins, Nova Scotia. As well as demonstrating the huge significance of Joggins, we hope that our findings will provide valuable guidelines for the assessment of World Heritage fossil sites in general. [source] Capturing the power of academic medicine to enhance health and health care of the elderly in the USAGERIATRICS & GERONTOLOGY INTERNATIONAL, Issue 1 2004William R Hazzard As in Japan, the US population is aging progressively, a trend that will challenge the health-care system to provide for the chronic, multiple and complex needs of its elderly citizens. and as in Japan, the US academic health enterprise has only belatedly mounted a response to that challenge. Herein is reviewed a quarter of a century of the author's personal experience in developing new programs in gerontology and geriatric medicine from a base in the Department of Internal Medicine at three US academic health centers (AHC): The University of Washington (as Division Head), Johns Hopkins University (as Vice-Chair), and Wake Forest University (as Chair). Rather than to build a program from a new department of geriatrics, this strategy was chosen to capture the power and resources of the department of internal medicine, the largest university department, to ,gerontologize' the institution, beginning with general internal medicine and all of the medical subspecialties (the approach also chosen to date at all but a handful of US AHC). The keystone of success at each institution has been careful faculty development through fellowship training in clinical geriatrics, education and research. Over the same interval major national progress has occurred, including expanded research and training at the National Institute on Aging and the Department of Veterans Affairs, and accreditation of more than 100 fellowship programs for training and certification of geriatricians. However, less than 1% of US medical graduates elect to pursue such training. Hence such geriatricians will remain concentrated at AHC, and most future geriatric care in the USA will be provided by a broad array of specialists, who will be educated and trained in geriatrics by these academic geriatricians. [source] Women and Classical Translation in the Eighteenth CenturyGERMAN LIFE AND LETTERS, Issue 3 2006Hilary Brown Women in Germany first began to take up their pens in substantial numbers during the eighteenth century. One area where they apparently did not leave their mark was in the translation of classical literature, despite a wave of interest in the classics in the literary world at large. However, this article sheds new light on women's involvement in this field. It focuses on a handful of women who translated from Greek or Latin, namely Luise Gottsched (1713,62), Fräulein von Erath (?,1776) and Ernestine Christine Reiske (1735,98). It looks at the conditions in which they did so, at their presentation of the texts, and at contemporary reactions to their work. It shows that women could only make their way in this area in exceptional cases, and that they usually exercised a considerable degree of caution. Yet, in some rare instances, translation gave women a new freedom. A translator could put her name to works of a surprising nature, such as philosophy and erotica. Adopting the detached stance of translator meant she could publish texts which women at the time would probably never have dared to write themselves. Thus, the act of translation could open up new spheres of literary activity for women. [source] Bastard Feudalism, Overmighty Subjects and Idols of the Multitude during the Wars of the RosesHISTORY, Issue 279 2000Michael Hicks A handful of overmighty subjects exercised a disproportionate influence on the events of the Wars of the Roses. This article considers how and why. Circumstances were certainly propitious. Not only did the greatest noblemen command exceptional resources of their own, albeit always less than the king, but they deployed the principal military commands against the crown and sought to enlist the populace on their side. Successful overmighty subjects were also idols of the multitude. Generally they failed and almost all died violently. Their misfortunes, a recovery of royal power and the disappearance of the desire to disturb the realm all help to explain the demise of their type. [source] Neuroendocrine mechanisms controlling female puberty: new approaches, new conceptsINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 1 2006Sergio R. Ojeda Summary Sexual development and mature reproductive function are controlled by a handful of neurones that, located in the basal forebrain, produce the decapeptide luteinizing hormone releasing hormone (LHRH). LHRH is released into the portal system that connects the hypothalamus to the pituitary gland and act on the latter to stimulate the synthesis and release of gonadotrophin hormones. The pubertal activation of LHRH release requires coordinated changes in excitatory and inhibitory inputs to LHRH-secreting neurones. These inputs are provided by both transsynaptic and glia-to-neurone communication pathways. Using cellular and molecular approaches, in combination with transgenic animal models and high-throughput procedures for gene discovery, we are gaining new insight into the basic mechanisms underlying this dual control of LHRH secretion and, hence, the initiation of mammalian puberty. Our results suggest that the initiation of puberty requires reciprocal neurone-glia communication involving excitatory amino acids and growth factors, and the coordinated actions of a group of transcriptional regulators that appear to represent a higher level of control governing the pubertal process. [source] BAYLOR UNIVERSITY ROUNDTABLE ON INTEGRITY IN FINANCIAL REPORTINGJOURNAL OF APPLIED CORPORATE FINANCE, Issue 3 2003Article first published online: 11 APR 200 At the center of the U.S. corporate governance controversy are questions about the integrity of the U.S. financial reporting system. Can investors trust the numbers now being reported in corporate financial statements? And, if not, what steps are being taken to bring about the return of investor trust and confidence? The academics and practitioners who took part in this discussion began by expressing their reluctance to describe the current situation as a "crisis." The consensus was that the recent governance failures are not the reflection of a general decline in corporate moral standards, but rather the work of a handful of opportunists who found ways to exploit some weaknesses in the present system. Part of the discussion focused on the expected benefits (and costs) of the heightened regulatory scrutiny provided by the Sarbanes-Oxley Act and the newly formed Public Company Accounting Oversight Board. But most of the panelists placed greater emphasis on the role of self-regulation in resolving problems such as the conflicts of interest within auditing and brokerage firms that played a major role in scandals like Enron and WorldCom. And rather than relying on more vigorous SEC oversight of financial statements, a number of panelists argued that top priority should be given to comprehensive reform of U.S. accounting standards, which are said to be a major source of confusion for both managers and investors. [source] Role of TIEG1 in biological processes and disease statesJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 3 2007Malayannan Subramaniam Abstract A novel TGF, Inducible Early Gene-1 (TIEG1) was discovered in human osteoblast (OB) cells by our laboratory. Over the past decade, a handful of laboratories have revealed a multitude of organismic, cellular, and molecular functions of this gene. TIEG1 is now classified as a member of the 3 zinc finger family of Krüppel-like transcription factors (KLF10). Other closely related factors [TIEG2 (KLF11) and TIEG3/TIEG2b] have been reported and are briefly compared. As described in this review, TIEG1 is shown to play a role in regulating estrogen and TGF, actions, the latter through the Smad signaling pathway. In both cases, TIEG1 acts as an inducer or repressor of gene transcription to enhance the TGF,/Smad pathway, as well at other signaling pathways, to regulate cell proliferation, differentiation, and apoptosis. This review outlines TIEG1's molecular functions and roles in skeletal disease (osteopenia/osteoporosis), heart disease (hypertrophic cardiomyopathy), and cancer (breast and prostate). J. Cell. Biochem. 102: 539,548, 2007. © 2007 Wiley-Liss, Inc. [source] The Internet and Youth Subculture in KuwaitJOURNAL OF COMPUTER-MEDIATED COMMUNICATION, Issue 2 2003Deborah L. Wheeler Young people in Kuwait constitute both the highest concentration of Internet users (estimated to be approximately 63% of all Internet users in Kuwait)and the largest sector of Kuwaiti society. Moreover, as argued in this article, young people's Internet practices are likely to stimulate the most significant changes in Kuwaiti society. This article scrutinizes a handful of descriptions by young Kuwaiti of the importance and implication of the Internet in their lives. [source] The Role of the Individual , A Key to Learning in Preparedness OrganizationsJOURNAL OF CONTINGENCIES AND CRISIS MANAGEMENT, Issue 3 2008Jerry Nilsson A well functioning societal response to crises is benefited by individuals having adequate skills and knowledge. From a municipal perspective this requires the creation of a learning organization. The objective of this study is to determine whether individual municipal employees, who have the responsibility for preparedness planning, reason and act in ways that promote learning about crises and preparedness issues throughout the municipal organization. Analysis of interviews with preparedness planners in six Swedish municipalities on their strategies for preparedness planning, reveal that preparedness planning too often becomes a demarcated activity, restricted to not more than a handful of individuals. This study indicates that one reason for why the preparedness work becomes demarcated is that individuals central to the preparedness planning are not taking on roles for acting in ways that are required in order for a learning organization to be established. [source] The case for sequencing the genome of the electric eel Electrophorus electricusJOURNAL OF FISH BIOLOGY, Issue 2 2008J. S. Albert A substantial international community of biologists have proposed the electric eel Electrophorus electricus (Teleostei: Gymnotiformes) as an important candidate for genome sequencing. In this study, the authors outline the unique advantages that a genome sequencing project of this species would offer society for developing new ways of producing and storing electricity. Over tens of millions of years, electric fish have evolved an exceptional capacity to generate a weak (millivolt) electric field in the water near their body from specialized muscle-derived electric organs, and simultaneously, to sense changes in this field that occur when it interacts with foreign objects. This electric sense is used both to navigate and orient in murky tropical waters and to communicate with other members of the same species. Some species, such as the electric eel, have also evolved a strong voltage organ as a means of stunning prey. This organism, and a handful of others scattered worldwide, convert chemical energy from food directly into workable electric energy and could provide important clues on how this process could be manipulated for human benefit. Electric fishes have been used as models for the study of basic biological and behavioural mechanisms for more than 40 years by a large and growing research community. These fishes represent a rich source of experimental material in the areas of excitable membranes, neurochemistry, cellular differentiation, spinal cord regeneration, animal behaviour and the evolution of novel sensory and motor organs. Studies on electric fishes also have tremendous potential as a model for the study of developmental or disease processes, such as muscular dystrophy and spinal cord regeneration. Access to the genome sequence of E. electricus will provide society with a whole new set of molecular tools for understanding the biophysical control of electromotive molecules, excitable membranes and the cellular production of weak and strong electric fields. Understanding the regulation of ion channel genes will be central for efforts to induce the differentiation of electrogenic cells in other tissues and organisms and to control the intrinsic electric behaviours of these cells. Dense genomic sequence information of E. electricus will also help elucidate the genetic basis for the origin and adaptive diversification of a novel vertebrate tissue. The value of existing resources within the community of electric fish research will be greatly enhanced across a broad range of physiological and environmental sciences by having a draft genome sequence of the electric eel. [source] A microarray's view of life in the desert: adding a powerful evolutionary genomics tool to the packrat's middenMOLECULAR ECOLOGY, Issue 11 2009MARJORIE D MATOCQ Identifying the genetic architecture of adaptive traits is fundamental to understanding how organisms respond to their environment, over both ecological and evolutionary timeframes. Microarray technology that allows us to capture the simultaneous expression of thousands of genes provides unparalleled insight into how organisms cope with their environment at the transcriptional level. Recent studies in Molecular Ecology demonstrate how microarrays can rapidly identify which genes and pathways allow organisms to face some of the most fundamental physiological challenges posed by the environment, including compensation for the hypoxic and thermal stress of high-altitudes (Cheviron et al. 2008) and, in this issue, the biotransformation of toxic plant secondary compounds by mammals (Magnanou et al. 2009). Microarrays (Ekins et al. 1989; Fodor et al. 1991) are glass slides affixed with hundreds to thousands of oligonucleotide or cDNA sequences (probes). Messenger RNA transcripts (typically reverse transcribed to cDNA) are isolated from a tissue/sample of interest and hybridized to the array. Binding to specific probes indicates that a particular gene was transcriptionally active at or near the time of sampling and thus provides a potentially comprehensive measure of gene expression. Although a tremendously powerful tool, commercially produced oligonucleotide arrays are only available for a handful of model organisms. Nonetheless, evolutionary ecologists have exploited this resource by using a cross-species hybridization approach (e.g. Saetre et al. 2004), that is, hybridizing a model organism array with a nonmodel sample (Bar-Or et al. 2007). Magnanou et al. (2009) present a novel example of using a model muroid microarray (Agilent Technologies, Rattus) to study physiological response in a wild, nonmodel muroid, Neotoma. [source] Genomic pattern of adaptive divergence in Arabidopsis halleri, a model species for tolerance to heavy metalMOLECULAR ECOLOGY, Issue 9 2009CLAIRE-LISE MEYER Abstract Pollution by heavy metals is one of the strongest environmental constraints in human-altered environments that only a handful of species can cope with. Identifying the genes conferring to those species the ability to grow in polluted areas is a first step towards a global understanding of the evolutionary processes involved and will eventually improve phytoremediation practices. We used a genome-scan approach to detect loci under divergent selection among four populations of Arabidopsis halleri growing on either polluted or nonpolluted habitats. Based on a high density of amplified fragment length polymorphism (AFLP) markers (820 AFLP markers, i.e. ~1 marker per 0.3 Mb), evidence for selection was found for some markers in every sampled population. Four loci departed from neutrality in both metallicolous populations and thus constitute high-quality candidates for general adaptation to pollution. Interestingly, some candidates differed between the two metallicolous populations, suggesting the possibility that different loci may be involved in adaptation in the different metallicolous populations. [source] Prospects for inferring pairwise relationships with single nucleotide polymorphismsMOLECULAR ECOLOGY, Issue 4 2003Jeffrey C. Glaubitz Abstract An extraordinarily large number of single nucleotide polymorphisms (SNPs) are now available in humans as well as in other model organisms. Technological advancements may soon make it feasible to assay hundreds of SNPs in virtually any organism of interest. One potential application of SNPs is the determination of pairwise genetic relationships in populations without known pedigrees. Although microsatellites are currently the marker of choice for this purpose, the number of independently segregating microsatellite markers that can be feasibly assayed is limited. Thus, it can be difficult to distinguish reliably some classes of relationship (e.g. full-sibs from half-sibs) with microsatellite data alone. We assess, via Monte Carlo computer simulation, the potential for using a large panel of independently segregating SNPs to infer genetic relationships, following the analytical approach of Blouin et al. (1996). We have explored a ,best case scenario' in which 100 independently segregating SNPs are available. For discrimination among single-generation relationships or for the identification of parent,offspring pairs, it appears that such a panel of moderately polymorphic SNPs (minor allele frequency of 0.20) will provide discrimination power equivalent to only 16,20 independently segregating microsatellites. Although newly available analytical methods that can account for tight genetic linkage between markers will, in theory, allow improved estimation of relationships using thousands of SNPs in highly dense genomic scans, in practice such studies will only be feasible in a handful of model organisms. Given the comparable amount of effort required for the development of both types of markers, it seems that microsatellites will remain the marker of choice for relationship estimation in nonmodel organisms, at least for the foreseeable future. [source] A deep Chandra survey of the Groth Strip , I. The X-ray dataMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2005K. Nandra ABSTRACT We present the results of a 200-ks Chandra observation of part of the Groth Strip region, using the ACIS-I instrument. We present a relatively simple method for the detection of point sources and calculation of limiting sensitivities, which we argue is at least as sensitive and more self-consistent than previous methods presented in the literature. A total of 158 distinct X-ray sources are included in our point-source catalogue in the ACIS-I area. The number counts show a relative dearth of X-ray sources in this region. For example, at a flux limit of 10,15 erg cm,2 s,1, around 20 per cent more soft-band sources are detected in the HDF-N and almost 50 per cent more in the ELAIS-N1 field, which we have analysed by the same method for comparison. We find, however, that these differences are consistent with Poisson variations at <2, significance, and therefore there is no evidence for cosmic variance based on these number counts alone. We determine the average spectra of the objects and find a marked difference between the soft-band-selected sources, which have ,= 1.9 typical of unobscured active galactic nuclei (AGN), and the hard-band-selected sources, which have ,= 1.0. Reassuringly, the sample as a whole has a mean spectrum of ,= 1.4 ± 0.1, the same as the X-ray background. None the less, our results imply that the fraction of sources with significant obscuration is only ,25 per cent, much less than predicted by standard AGN population synthesis models. This is confirmed by direct spectral fitting, with only a handful of objects showing evidence for absorption. After accounting for absorption, all objects are consistent with a mean intrinsic spectrum of ,= 1.76 ± 0.08, very similar to local Seyfert galaxies. The survey area is distinguished by having outstanding multiwaveband coverage. Comparison with these observations and detailed discussion of the X-ray source properties will be presented in future papers. [source] On the evolution of young radio-loud AGNMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2000I. A. G. Snellen This paper describes an investigation of the early evolution of extragalactic radio sources using samples of faint and bright gigahertz peaked spectrum (GPS) and compact steep spectrum (CSS) radio galaxies. Correlations found between their peak frequency, peak flux density and angular size provide strong evidence that synchrotron self-absorption is the cause of the spectral turnovers, and indicate that young radio sources evolve in a self-similar way. In addition, the data seem to suggest that the sources are in equipartition while they evolve. If GPS sources evolve to large size radio sources, their redshift dependent birth-functions should be the same. Therefore, since the lifetimes of radio sources are thought to be short compared to the Hubble time, the observed difference in redshift distribution between GPS and large size sources must be due to a difference in slope of their luminosity functions. We argue that this slope is strongly affected by the luminosity evolution of the individual sources. A scenario for the luminosity evolution is proposed in which GPS sources increase in luminosity and large-scale radio sources decrease in luminosity with time. This evolution scenario is expected for a ram-pressure confined radio source in a surrounding medium with a King profile density. In the inner parts of the King profile, the density of the medium is constant and the radio source builds up its luminosity, but after it grows large enough the density of the surrounding medium declines and the luminosity of the radio source decreases. A comparison of the local luminosity function (LLF) of GPS galaxies with that of extended sources is a good test for this evolution scenario. Unfortunately, only a handful of GPS sources are known at low redshift, and an LLF can only be derived, assuming that their cosmological number density evolution is similar to that of steep spectrum sources. The LLF derived in this way is shown to be in good agreement with the proposed evolution scenario. However, the uncertainties are large, and larger, homogeneously selected samples of GPS sources are needed. [source] Squamous cell carcinoma: a rare complication of dermoid cystsNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 2 2002K. Ashkan Introduction:, Dermoid cysts constitute 0.3% of all brain tumours. Carcinomatous differentiation has been described only in a handful of cases. Material and methods:, A 44-year-old-man presented with a several-year history of headaches and a 5-week history of progressive visual deterioration in the left eye. Clinical examination confirmed a normal visual acuity but an impaired left visual field. A magnetic resonance imaging scan showed a lesion in the left paraclinoid area compressing the ipsilateral optic nerve. Signal characteristics of the lesion were consistent with a dermoid or epidermoid cyst. At operation, the lesion was thought to be typical of a dermoid cyst and a near-complete excision was achieved leaving behind parts adherent to the optic nerve. Histology showed invasive squamous cell carcinoma arising within the dermoid tumour. Postoperatively the patient received radiotherapy. Results:, The patient's clinical condition initially stabilized. At 15 months follow up, however, there was clinical and radiological evidence of tumour progression and he died 1 year later. Conclusion:, Squamous cell carcinoma may rarely arise from an intracranial dermoid tumour. This may hinder total excision of the lesion and confounds the prognosis. [source] Another country is the past: Western cowboys, Lanna nostalgia, and bluegrass aesthetics as performed by professional musicians in Northern ThailandAMERICAN ETHNOLOGIST, Issue 2 2010JANE M. FERGUSON ABSTRACT Within the popular music scene of Chiang Mai, Northern Thailand, a handful of restaurants feature live bluegrass bands, with musicians often dressed in U.S. western-style cowboy attire. By intermingling English-language songs with Lanna (Northern Thai) popular songs performed in the style of Appalachian bluegrass music, they use their illusion of the cowboy myth to point to notions of an authentic Lanna past. However, in their borrowing of this international code, they affirm established (Central) Thai boundaries of ethnonational gatekeeping. [Lanna, Thailand, cowboys, music, nostalgia, bluegrass, identity] [source] Design and statistical analysis of oral medicine studies: common pitfallsORAL DISEASES, Issue 3 2010L Baccaglini Oral Diseases (2010) 16, 233,241 A growing number of articles are emerging in the medical and statistics literature that describe epidemiologic and statistical flaws of research studies. Many examples of these deficiencies are encountered in the oral, craniofacial, and dental literature. However, only a handful of methodologic articles have been published in the oral literature warning investigators of potential errors that may arise early in the study and that can irreparably bias the final results. In this study, we briefly review some of the most common pitfalls that our team of epidemiologists and statisticians has identified during the review of submitted or published manuscripts and research grant applications. We use practical examples from the oral medicine and dental literature to illustrate potential shortcomings in the design and analysis of research studies, and how these deficiencies may affect the results and their interpretation. A good study design is essential, because errors in the analysis can be corrected if the design was sound, but flaws in study design can lead to data that are not salvageable. We recommend consultation with an epidemiologist or a statistician during the planning phase of a research study to optimize study efficiency, minimize potential sources of bias, and document the analytic plan. [source] Identification of uniquely expressed transcription factors in highly purified B-cell lymphoma samples,,§AMERICAN JOURNAL OF HEMATOLOGY, Issue 6 2010Ulrika Andréasson Transcription factors (TFs) are critical for B-cell differentiation, affecting gene expression both by repression and transcriptional activation. Still, this information is not used for classification of B-cell lymphomas (BCLs). Traditionally, BCLs are diagnosed based on a phenotypic resemblance to normal B-cells; assessed by immunohistochemistry or flow cytometry, by using a handful of phenotypic markers. In the last decade, diagnostic and prognostic evaluation has been facilitated by global gene expression profiling (GEP), providing a new powerful means for the classification, prediction of survival, and response to treatment of lymphomas. However, most GEP studies have typically been performed on whole tissue samples, containing varying degrees of tumor cell content, which results in uncertainties in data analysis. In this study, global GEP analyses were performed on highly purified, flow-cytometry sorted tumor-cells from eight subgroups of BCLs. This enabled identification of TFs that can be uniquely associated to the tumor cells of chronic lymphocytic leukemia (CLL), diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), hairy cell leukemia (HCL), and mantle cell lymphoma (MCL). The identified transcription factors influence both the global and specific gene expression of the BCLs and have possible implications for diagnosis and treatment. Am. J. Hematol., 2010. © 2010 Wiley-Liss, Inc. [source] Gene stacking in transgenic plants , the challenge for 21st century plant biotechnologyPLANT BIOTECHNOLOGY JOURNAL, Issue 2 2005Claire Halpin Summary One of the major technical hurdles impeding the advance of plant genetic engineering and biotechnology is the fact that the expression or manipulation of multiple genes in plants is still difficult to achieve. Although a small proportion of commercial genetically modified (GM) crops present ,stacked' or ,pyramided' traits, only a handful of products have been developed by introducing three or more novel genes. On the research front, a variety of conventional and more novel methods have been employed to introduce multiple genes into plants, but all techniques suffer from certain drawbacks. In this review, the potential and problems of these various techniques and strategies are discussed, and the prospects for improving these technologies in the future are presented. [source] One agent, many diseases: Exposure-response data and comparative risks of different outcomes following silica exposure,AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 1 2005Kyle Steenland Abstract Background Evidence in recent years indicates that silica causes lung cancer, and probably renal disease, in addition to its well-known relationship to silicosis. There is also suggestive evidence that silica can cause arthritis and other auto-immune diseases. Silica has, therefore, joined a handful of other toxic exposures such as tobacco smoke, dioxin, and asbestos which cause multiple serious diseases. Methods The available exposure-response data for silica and silicosis, lung cancer, and renal disease are reviewed. We compare the corresponding excess risks (or absolute risks in the case of silicosis) of death or disease incidence by age 75 for these three diseases, subsequent to a lifetime (45 years) of exposure to silica at current US standard (0.1 mg/m3 respirable crystalline silica). Results The absolute risk of silicosis, as defined by small opacities greater than or equal to ILO classification 1/1 on an X-ray, ranges from 47% to 77% in three cohort studies with adequate follow-up after employment. The absolute risk of death from silicosis is estimated at 1.9% (0.8%,2.9%), based on a pooled analysis of six cohort studies. The excess risk of lung cancer death, assuming US male background rates, is 1.7% (0.2%,3.6%), based on a pooled analysis of ten cohort studies. The excess risk of end-stage renal disease (assuming male background rates) is 5.1% (2.2%,7.3%), based on a single cohort. The excess risk of death from renal disease is estimated to be 1.8% (0.8%,9.7%), based on a pooled analysis of three cohorts. Conclusions Keeping in mind that the usual OSHA acceptable excess risk of serious disease or death for workers is 0.1%, it is clear that the current standard is far from sufficiently protective of workers' health. Perhaps surprisingly, kidney disease emerges as perhaps a higher risk than either mortality from silicosis or lung cancer, although the data are based on fewer studies. Am. J. Ind. Med. 48:16,23, 2005. © 2005 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||||||||