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Selected AbstractsMeasurement Equivalence Using Generalizability Theory: An Examination of Manufacturing Flexibility DimensionsDECISION SCIENCES, Issue 4 2008Manoj K. Malhotra ABSTRACT As the field of decision sciences in general and operations management in particular has matured from theory building to theory testing over the past two decades, it has witnessed an explosion in empirical research. Much of this work is anchored in survey-based methodologies in which data are collected from the field in the form of scale items that are then analyzed to measure latent unobservable constructs. It is important to assess the invariance of scales across groups in order to reach valid, scientifically sound conclusions. Because studies have often been conducted in the field of decision sciences with small sample sizes, it further exacerbates the problem of reaching incorrect conclusions. Generalizability theory can more effectively test for measurement equivalence in the presence of small sample sizes than the confirmatory factor analysis (CFA) tests that have been conventionally used for assessing measurement equivalency across groups. Consequently, we introduce and explain the generalizability theory (G-theory) in this article to examine measurement equivalence of 24 manufacturing flexibility dimension scales that have been published in prior literature and also compare and contrast G-theory with CFA. We show that all the manufacturing flexibility scales tested in this study were invariant across the three industry SIC groups from which data were collected. We strongly recommend that G-theory should always be used for determining measurement equivalence in empirical survey-based studies. In addition, because using G-theory alone does not always reveal the complete picture, CFA techniques for establishing measurement equivalence should also be invoked when sample sizes are large enough to do so. Implications of G-theory for practice and its future use in operations management and decision sciences research are also presented. [source] The simultaneous consideration of between-participants and within-participants analyses in research on predictors of behaviours: The issue of dependenceEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 6 2004Dr David Trafimow Although there is wide acceptance among personality and social psychologists of the importance of performing both between-participants and within-participants analyses to obtain a more complete picture of the phenomena under investigation, such analyses are rare (Mishela, 1990). Research on the predictors of behaviour, particularly concerning variables such as attitude, subjective norm, affect, cognition, and intention provides an exception, where the results from within-participants analyses are sometimes compared to the results from between-participants analyses. These comparisons raise the issue of whether the two types of analyses are independent of each other (and whether they can be validly compared), which is the topic of the present paper. Although we show that there is dependence, which suggests that it is a bad idea to compare both kinds of analyses, we also show that the degree of dependence approaches zero as the number of participants and items increase. Thus, with a sufficiently large design, the degree of dependence is unimportant, and therefore is no obstacle to the simultaneous consideration of both within-participants and between-participants analyses. How large is large enough? A set of computer simulations suggests that 15 participants and 15 items is sufficient, though we provide data from which researchers can designate their own criteria. Copyright © 2004 John Wiley & Sons, Ltd. [source] ECOLOGICAL AND DEVELOPMENTAL CONTEXT OF NATURAL SELECTION: MATERNAL EFFECTS AND THERMALLY INDUCED PLASTICITY IN THE FROG BOMBINA ORIENTALISEVOLUTION, Issue 1 2006Robert H. Kaplan Abstract Variation in fitness generated by differences in functional performance can often be traced to morphological variation among individuals within natural populations. However, morphological variation itself is strongly influenced by environmental factors (e.g., temperature) and maternal effects (e.g., variation in egg size). Understanding the full ecological context of individual variation and natural selection therefore requires an integrated view of how the interaction between the environment and development structures differences in morphology, performance, and fitness. Here we use naturally occurring environmental and maternal variation in the frog Bombina orientalis in South Korea to show that ovum size, average temperature, and variance in temperature during the early developmental period affect body sizes, shapes, locomotor performance, and ultimately the probability of an individual surviving interspecific predation in predictable but nonadditive ways. Specifically, environmental variability can significantly change the relationship between maternal investment in offspring and offspring fitness so that increased maternal investment can actually negatively affect offspring over a broad range of environments. Integrating environmental variation and developmental processes into traditional approaches of studying phenotypic variation and natural selection is likely to provide a more complete picture of the ecological context of evolutionary change. [source] Diel variation in the seagrass ichthyofaunas of three intermittently open estuaries in south-eastern Australia: implications for improving fish diversity assessmentsFISHERIES MANAGEMENT & ECOLOGY, Issue 2 2001S. P. Griffiths Diel variation in the ichthyofaunas associated with Zostera capricorni Ascherson was investigated in three intermittently open estuaries in the Illawarra region, New South Wales. Each estuary showed differing diel shifts in fish assemblages, which appeared to be related to estuary size. In the largest estuary (Lake Illawarra) significantly more species were caught during the night than the day for all months. In contrast, there was little diel variation in the fish assemblages at Werri Lagoon and Shellharbour Lagoon, although many species were only caught during the night at both estuaries. The distinct diel changes at Lake Illawarra was thought to be attributable to the relatively deep channels adjacent to the seagrass beds which are better habitats for larger fishes compared with the shallow sand bars without deep channels throughout the two smaller estuaries. The composition of fish species within the three estuaries were significantly different, although each assemblage was characterised by large numbers of small-sized fish (<100 mm FL) indicating the importance of intermittently open estuaries as fish habitats. It was concluded that night sampling provided a more complete picture of the ichthyofaunas associated with Z. capricorni. As a result, inclusion of night sampling in fish diversity assessments would increase the chance of catching diurnally rare species and therefore attain a better representation of the true community structure. [source] Effects of ontogeny, temperature, and light on vertical movements of larval Pacific cod (Gadus macrocephalus)FISHERIES OCEANOGRAPHY, Issue 5 2009THOMAS P. HURST Abstract The role of behavior, especially vertical migration, is recognized as a critical component of realistic models of larval fish dispersion. Unfortunately, our understanding of these behaviors lags well behind our ability to construct three-dimensional flow-field models. Previous field studies of vertical behavior of larval Pacific cod (Gadus macrocephalus) were limited to small, preflexion stages (,11 mm SL) in a narrow range of thermal conditions. To develop a more complete picture of larval behavior, we examined the effects of ontogeny, temperature, and light on vertical responses of larval Pacific cod in experimental columns. While eggs were strictly demersal, yolk-sac larvae displayed a strong surface orientation as early as 1 day post hatch (, 5 mm SL). Consistent with field observations, small preflexion larvae (<10 mm SL) showed no response to varying light levels. However, there was a direct effect of temperature on larval behavior: Pacific cod larvae exhibited a stronger surface orientation at 4°C than at 8°C. The behavior of larger, postflexion larvae (>15 mm SL) in experimental columns was consistent with a diel vertical migration and independent of water temperature: fish were more widely distributed in the column, and median positions were consistently deeper at higher light levels. These laboratory observations are combined with observations from discrete-depth (MOCNESS) sampling in the Gulf of Alaska to characterize the vertical distribution of larval Pacific cod and contrast ontogenetic patterns with walleye pollock (Theragra chalcogramma). The vertical movements of larval Pacific cod described here will be applied in the development of dispersal projections from Gulf of Alaska spawning grounds. [source] Day,night changes in the spatial distribution and habitat preferences of freshwater shrimps, Gammarus pulex, in a stony streamFRESHWATER BIOLOGY, Issue 4 2005J. M. ELLIOTT Summary 1. As many invertebrates are nocturnal, their spatial distribution and habitat preferences may change from day to night. Both aspects are examined for Gammarus pulex by testing the hypotheses: (i) a power function was a suitable model for the spatial distribution of the shrimps in both day and night; (ii) diurnal and nocturnal spatial distributions were significantly different; (iii) diurnal and nocturnal habitat preferences were significantly different. Five different life-stages were treated separately. To ensure that the conclusions were consistent, large samples were taken near midday and midnight in April, June and November over 4 years at two sites about 3 km apart in a stony stream: downstream (n = 30) and upstream (n = 50). 2. The first and second hypotheses were supported at both sites. A power function, relating spatial variance (s2) to mean (m), was an excellent fit in all analyses (P < 0.001, r2 > 0.91), i.e. the spatial variance was density-dependent. All five life-stages were aggregated in the day. At night, the degree of aggregation increased for juveniles at higher densities but decreased for juveniles at lower densities, increased for immature females and males, but decreased slightly for mature females and especially mature males, the latter being close to a random distribution. There were no significant differences between sites, in spite of the lower numbers at the downstream site. 3. The third hypothesis was tested at only the upstream site and supported by comparisons between shrimp densities and 13 physical variables (distance from bank, water depth, water velocity, ten particle size-classes), and three non-physical variables (dry weights of bryophytes, leaf material, organic detritus). During the day, densities were strongly related to particle sizes with the following preferences: 0.5,8 mm for juveniles, 8,256 mm for the other life-stages with a weaker relationship for males. There were no significant positive relationships with the other variables, apart from bryophytes for immature shrimps and adults. At night, densities were unrelated to particle size; juveniles and immature shrimps preferred low water velocities near the banks, often where leaf material and organic detritus accumulated, females often preferred medium water velocities slightly away from the banks, and males showed no habitat preferences. 4. Day samples do not provide a complete picture of habitat preferences and probably identify refuge habitats. Day,night changes in spatial distribution and habitat preferences are an essential part of the behavioural dynamics of the shrimps and should be investigated in other species. [source] Antiplatelet ,resistance' and ,non-responders': what do these terms really mean?FUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 1 2009Victor L. Serebruany Abstract The term ,resistance' should be restricted to very specialized physiologic circumstances, if not abandoned altogether. The term ,non-responder' needs to be placed in the context of the question: ,Non-responder to what?' Even if we would somehow magically know what an optimal response to antiplatelet therapy was, it will still be challenging to demonstrate an ,inadequate' response to antiplatelet therapy. At present there are two alternatives , give more drug or give additional drugs. Both strategies may work in further inhibiting platelet function, but both strategies can also be associated with an increased risk of bleeding. The trick, for the future, much as with our antihypertensive and lipid-lowering armamentaria, will be to know in whom to do what with which drug, and why. Single isolated measurements are not useful , if you don't know where you started, how we would know that antiplatelet drug is producing an ,adequate' clinical effect? There is no evidence of any sort of absolute ,threshold' that must be exceeded for treatment to be effective, and in the absence of this, if we are to evaluate the effect of a given drug, we have to have baseline values (off drug), therapeutic values (on drug), and some sort of assessment of both resting (unstimulated) and agonist-provoked (stimulated) platelet function. Moreover, given all of the different things that platelets do, the ideal assessment of platelet function and drug responsiveness will need to incorporate more than one agonist and some sort of assessment of both platelet activation and platelet aggregation. No one man (or test) tells us everything; it is the totality of the information that gives us the most complete picture. And, ultimately, we need to more firmly establish how the variability in platelet function and drug-associated changes in that function correlates with long-term, hard-endpoint clinical events. [source] Electronic and Magnetic Properties of SrTiO3/LaAlO3 Interfaces from First PrinciplesADVANCED MATERIALS, Issue 26-27 2010Hanghui Chen Abstract A number of intriguing properties emerge upon the formation of the epitaxial interface between the insulating oxides LaAlO3 and SrTiO3. These properties, which include a quasi two-dimensional conducting electron gas, low temperature superconductivity, and magnetism, are not present in the bulk materials, generating a great deal of interest in the fundamental physics of their origins. While it is generally accepted that the novel behavior arises as a result of a combination of electronic and atomic reconstructions and growth-induced defects, the complex interplay between these effects remains unclear. In this report, we review the progress that has been made towards unraveling the complete picture of the SrTiO3/LaAlO3 interface, focusing primarily on present ab initio theoretical work and its relation to the experimental data. In the process, we highlight some key unresolved issues and discuss how they might be addressed by future experimental and theoretical studies. [source] Quality of offering on the world wide webINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 9 2002G. Mantzaridis Abstract The definition of quality in a ,life' environment, such as that of the World Wide Web has proven to have many, often conflicting interpretations. Factors such as the point of view, the expertise and type of usage of the critic can influence dramatically such a definition and its results. Thus, the key point is to distance oneself from single perspectives and obtain a complete picture of the system as a single entity working towards a specific goal. This paper is an attempt at creating a general model of quality procedures. It will concentrate mainly in customer service, system viability and quality of offering evaluation. Some of the material mentioned is based on adapted classical models that can be used equally to apply and observe standards of offerings in the wider WEB community. Copyright © 2002 John Wiley & Sons, Ltd. [source] Operations research and ethics: development trends 1966,2009INTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH, Issue 4 2010Fred Wenstřp Abstract The paper tracks development trends in the literature on operations research (OR) and ethics from Kenneth Boulding's vision in 1966 of OR as a tool for benevolent decision making, and up to today's constructive papers in this special issue of ITOR. Although this review does not intend to give a complete picture of the relevant literature, two main themes stand out clearly: "Guidelines for the practice of OR" and "How can OR be applied for good purpose?" The first issue is about ethical principles and the second about ethical consequences. Although there is a continued interest in guidelines, few OR societies follow up with their own guidelines, and only a limited number of papers report on the ethicality of real OR applications in relation to guidelines. On the other hand, there is an increasing interest in OR as a tool for benevolent decision making, as we can witness in this special issue of ITOR. [source] Blood group antigens and immune responses,detailed knowledge is necessary to prevent immunization and to follow up immunized individualsISBT SCIENCE SERIES: THE INTERNATIONAL JOURNAL OF INTRACELLULAR TRANSPORT, Issue n1 2010A. Husebekk Background The immune system is educated to detect and react with foreign antigens and to tolerate self-antigen. Transfusion of blood cells and plasma and pregnancies challenge the immune system by the introduction of foreign antigens. The antigens may cause an immune response, but in many instances this is not the case and the individual is not immunised after exposure of blood group antigens. Aims The aim of the presentation is to dissect some immune responses to blood group antigens in order to understand the mechanism of immunisation. Methods The results of immune responses to blood group antigens can be detected by the presence of antibodies to the antigens. If the antibodies are of IgG class, the activated B cells have received help from antigen specific T cells. Both antibodies, B cells and T cells can be isolated from immunised individuals and studied in the laboratory. Also B-cell receptors and T-cell receptors as well as MHC molecules on antigen presenting cells can be studied and models of the immune synapses can be created in vitro. Results The most classic immune responses in transfusion medicine and in incompatible pregnancies are immune responses to the RhD antigen on red cells, HLA class I molecules on white cells and platelets and human platelet antigens. The nature of these antigens are different; RhD antigens are part of a large complex, present on red cells from RhD positive individuals and completely lacking on red cells from RhD negative individuals. It is likely that many peptides derived from this antigen complex may stimulate T cells and B cells. HLA antigens are highly polymorphic and the antigens are known to induce strong alloimmune responses. The HPA antigens are created by one amino acid difference in allotypes based on a single nucleotide polymorphism at the genetic level. HPA 1a induce immune responses in 10% of HPA 1b homozygote pregnant women. The result of these immune responses is destruction of blood cells with clinical consequences connected to the effect of transfusions or the outcome of pregnancies. Summary/Conclusions Even though there is emerging knowledge about the immune responses to some of the blood group antigens, more information must be gained in order to understand the complete picture. The action of the innate immune response initiating the adaptive immune response to blood group antigens is not well understood. A detailed understanding of both the innate ad the adaptive part of the immune response is necessary to identify individuals at risk for immunisation and to prevent immunisation to blood group antigens. [source] Strength-based assessment in clinical practice,JOURNAL OF CLINICAL PSYCHOLOGY, Issue 5 2009Tayyab Rashid Abstract Strength-based assessment can enhance clinical clarity, improve the range of information, and provide a more complete picture of clients and their circumstances. Deficit-oriented assessment has improved the assessment and treatment of a number of disorders but, at the same time, has created a negative bias, considered strengths as clinical peripheries or by-products, tended to reduce clients to diagnostic categories, and created a power differential, which could be counterproductive to clinical efficacy. Strength-based assessment explores weaknesses as well as strengths to effectively deal with problems. We present a number of strength-based strategies for use in clinical practice. These strategies, we hope, will help clinicians to operationalize how strengths and weaknesses reverberate and contribute to a client's psychological status, which is comprehensive and guards against negative bias. © 2009 Wiley Periodicals, Inc. J Clin Psychol: In Session 65: 1,11, 2009. [source] Resolution of structure characteristics of AE signals in multiphase flow system,From data to informationAICHE JOURNAL, Issue 10 2009Yi-Jun He Abstract This investigation was performed to study the underlying structure characteristics of acoustic emission (AE) signals, which could be helpful not only to understand a relatively complete picture of hydrodynamics in multiphase flow systems, but also to extract the most useful information from the original signals with respect to a particular measurement requirement. However, due to AE signals are made up of emission from many acoustic sources at different scales, the resolution of AE signals is often very complicated and appears to be relatively poorly researched. In this study, the structure characteristics of AE signals measured both in gas,solid fluidized bed and liquid,solid stirred tank were researched in detail by resorting to wavelet transform and rescaled range analysis. A general criterion was proposed to resolve AE signals into three physical-related characteristic scales, i.e., microscale, mesoscale, and macroscale. Multiscale resolution of AE signals implied that AE signals in microscale represented totally the dynamics of solid phase and could be applied to measure particle-related properties. Furthermore, based on the structure characteristics of AE signals, useful features related to particles motion were extracted to establish two new prediction models, one for on-line measurements of particle size distribution (PSD) and average particle size in gas,solid fluidized bed and the other for on-line measurement of the suspension height in liquid,solid stirred tank. The prediction results indicated that (1) measurements of PSD and average particle size using AE method showed a fairly good agreement with that using sieve method both for laboratory scale and plant scale fluidized beds, and (2) measurements of the suspension height using AE method showed a fairly good agreement with that using visual method. The results thus validated that the extracted features based on analyses of structure characteristics of AE signals were very useful for establishing effective on-line measurement models with respect to some particular applications. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Epidemiology of varicella-zoster virus in England and WalesJOURNAL OF MEDICAL VIROLOGY, Issue S1 2003M. Brisson Abstract Many countries are studying currently the possibility of mass vaccination against varicella. The objective of this study was to provide a complete picture of the pre-vaccine epidemiology of the Varicella-Zoster Virus in England and Wales to aid in the design of immunisation programs. Population-based data including general practitioner sentinel surveillance, hospitalisation data, and death certificates from England and Wales were analysed. The average incidence rates for varicella and zoster between 1991 and 2000 were 1,291 and 373 per 100,000 years, respectively. Overall hospitalisation rates were equal for varicella and zoster (4.5 vs. 4.4 hospitalisation per 100,000 population) with 5 and 8%, respectively, having underlying immunosuppressive conditions. The age-specific proportion of cases hospitalised and length of stay were similar between the two diseases. However, the overall burden of disease is considerably higher for zoster. The number of inpatient days and case-fatality due to zoster are roughly 4 to 6 times greater than for varicella (11 vs. 3 days and 25 vs. 4 deaths per 100,000 case). These results provide base-line estimates should mass varicella vaccination be introduced in England and Wales. J. Med. Virol. 70:S9,S14, 2003. © 2003 Wiley-Liss, Inc. [source] Towards correlative imaging of plant cortical microtubule arrays: combining ultrastructure with real-time microtubule dynamicsJOURNAL OF MICROSCOPY, Issue 3 2009D.A. BARTON Summary There are a variety of microscope technologies available to image plant cortical microtubule arrays. These can be applied specifically to investigate direct questions relating to array function, ultrastructure or dynamics. Immunocytochemistry combined with confocal laser scanning microscopy provides low resolution "snapshots" of cortical microtubule arrays at the time of fixation whereas live cell imaging of fluorescent fusion proteins highlights the dynamic characteristics of the arrays. High-resolution scanning electron microscopy provides surface detail about the individual microtubules that form cortical microtubule arrays and can also resolve cellulose microfibrils that form the innermost layer of the cell wall. Transmission electron microscopy of the arrays in cross section can be used to examine links between microtubules and the plasma membrane and, combined with electron tomography, has the potential to provide a complete picture of how individual microtubules are spatially organized within the cortical cytoplasm. Combining these high-resolution imaging techniques with the expression of fluorescent cytoskeletal fusion proteins in live cells using correlative microscopy procedures will usher in an radical change in our understanding of the molecular dynamics that underpin the organization and function of the cytoskeleton. [source] The synapsin cycle: A view from the synaptic endocytic zoneJOURNAL OF NEUROSCIENCE RESEARCH, Issue 12 2007E. Evergren Abstract Although the synapsin phosphoproteins were discovered more than 30 years ago and are known to play important roles in neurotransmitter release and synaptogenesis, a complete picture of their functions within the nerve terminal is lacking. It has been shown that these proteins play an important role in the clustering of synaptic vesicles (SVs) at active zones and function as modulators of synaptic strength by acting at both pre- and postdocking levels. Recent studies have demonstrated that synapsins migrate to the endocytic zone of central synapses during neurotransmitter release, which suggests that there are additional functions for these proteins in SV recycling. © 2007 Wiley-Liss, Inc. [source] Work values: Development of a new three-dimensional structure based on confirmatory smallest space analysisJOURNAL OF ORGANIZATIONAL BEHAVIOR, Issue 7 2010Sean T. Lyons We tested the psychological structure of the work values ratings of 119,167 Canadian workers using confirmatory smallest space analysis (SSA). Contrary to our hypotheses, the SSA did not support a two-dimensional radex structure, but suggested a three-dimensional cylindrex structure composed of three facets: (a) A modality facet comprised of four types of work values (cognitive, instrumental, social, and prestige) forming angular sectors of a circle; (b) a growth-orientation facet with growth-related work aspects located closest to the center of the circle and context-related work aspects located in the peripheral ring; and (c) a level of focus facet that divided the overall cylindrical structure into three separate vertical levels (individual, job/organizational, and societal). The findings extend the theory of work values by providing a richer typology of work values and a more complete picture of the complex structure of their inter-relations. Copyright © 2009 John Wiley & Sons, Ltd. [source] Prevalence of Xerostomia in Population-based Samples: A Systematic ReviewJOURNAL OF PUBLIC HEALTH DENTISTRY, Issue 2 2006M.F. Orellana DDS Abstract The consequences of xerostomia on oral health have been studied for decades; however, the actual prevalence of this disorder on the general population remains controversial. The purpose of this systematic review was to determine the prevalence of xerostomia in population-based samples. Electronic databases were screened for relevant articles and reference lists of pertinent articles were also hand-searched. Thirteen articles meeting the final inclusion criteria were identified. Based on the definition of xerostomia used in this review, only publications including a subjective diagnosis of the disorder were included. All of the self-repotted diagnoses were achieved through a questionnaire either by mail, telephone, interview or self-administered by the patient. There was a variation across papers regarding number and content of the questions as well as guidelines for the diagnosis of xerostomia (i.e. answer yes to one or more than one question). The prevalence of xerostomia in the selected articles ranged from 0.9% to 64.8%. The majority of these studies were performed in Scandinavia. In 9 of the articles, the studied samples were 50 years and older. None of the studies evaluated the prevalence xerostomia among individuals younger than 18 years. Based on these observations, it can be concluded that there is a need for population-based studies on prevalence of xerostomia in regions other than Scandinavia. A standardized protocol to diagnose xerostomia needs to be developed. Patient-perceived treatment needs and impact on quality of life should be included to have a complete picture of public health implications of the disease. [source] Review of methods for measuring and comparing center performance after organ transplantationLIVER TRANSPLANTATION, Issue 10 2010James Neuberger The assessment of outcomes after transplantation is important for several reasons: it provides patients with data so that they can make informed decisions about the benefits of transplantation and the success of the transplant unit; it informs commissioners that resources are allocated properly; and it provides clinicians reassurance that results are acceptable or, if they are not, provides early warning so that problems can be identified, corrections can be instituted early, and all interested parties can be reassured that scarce resources are used fairly. The need for greater transparency in reporting outcomes after liver transplantation and for comparisons both between and within centers has led to a number of approaches being adopted for monitoring center performance. We review some of the commonly used methods, highlight their strengths and weaknesses, and concentrate on methods that incorporate risk adjustment. Measuring and comparing outcomes after transplantation is complex, and there is no single approach that gives a complete picture. All those using analyses of outcomes must understand the merits and limitations of individual methods. When used properly, such methods are invaluable in ensuring that a scarce resource is used effectively, any adverse trend in outcomes is identified promptly and remedied, and best performers are identified; they thus allow the sharing of best practices. However, when they are used inappropriately, such measurements may lead to inappropriate conclusions, encourage risk-averse behavior, and discourage innovation. Liver Transpl 16:1119,1128, 2010. © 2010 AASLD. [source] Two Coexisting Modes in Field-Assisted AFM Nanopatterning of Thin Polymer FilmsMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 13 2008Xian Ning Xie Abstract Two coexisting mechanisms, i.e., electrohydrodynamic destabilization and electrostatic detachment, for polymer nanostructuring in field-assisted atomic force microscope nanolithography are presented. The electrohydrodynamic destabilization mechanism is based on the surface instability of molten polymer film in the form of surface waves, and it leads to the formation of well defined polymeric wave patterns. The electrostatic detachment mechanism is associated with nano-blister formation caused by pre-existing defects, such as buried cavities in the polymer, and is responsible for the creation of hollow pillar-like structures. Here, the coexistence and pattern formation probability of the two polymer patterning modes under similar nanolithographic conditions are discussed. It was found that the field strength and the efficiency of probe-induced joule heating can significantly change the flow property of the polymer, which eventually leads to the occurrence of the two modes. The results presented here are useful in obtaining a complete picture of the diverse behaviors of polymers in AFM nanolithographic operations. [source] DNA barcoding of Cuban freshwater fishes: evidence for cryptic species and taxonomic conflictsMOLECULAR ECOLOGY RESOURCES, Issue 3 2010ARIAGNA LARA Abstract Despite ongoing efforts to protect species and ecosystems in Cuba, habitat degradation, overuse and introduction of alien species have posed serious challenges to native freshwater fish species. In spite of the accumulated knowledge on the systematics of this freshwater ichthyofauna, recent results suggested that we are far from having a complete picture of the Cuban freshwater fish diversity. It is estimated that 40% of freshwater Cuban fish are endemic; however, this number may be even higher. Partial sequences (652 bp) of the mitochondrial gene COI (cytochrome c oxidase subunit I) were used to barcode 126 individuals, representing 27 taxonomically recognized species in 17 genera and 10 families. Analysis was based on Kimura 2-parameter genetic distances, and for four genera a character-based analysis (population aggregation analysis) was also used. The mean conspecific, congeneric and confamiliar genetic distances were 0.6%, 9.1% and 20.2% respectively. Molecular species identification was in concordance with current taxonomical classification in 96.4% of cases, and based on the neighbour-joining trees, in all but one instance, members of a given genera clustered within the same clade. Within the genus Gambusia, genetic divergence analysis suggests that there may be at least four cryptic species. In contrast, low genetic divergence and a lack of diagnostic sites suggest that Rivulus insulaepinorum may be conspecific with Rivulus cylindraceus. Distance and character-based analysis were completely concordant, suggesting that they complement species identification. Overall, the results evidenced the usefulness of the DNA barcodes for cataloguing Cuban freshwater fish species and for identifying those groups that deserve further taxonomic attention. [source] Apoptosis in amyotrophic lateral sclerosis: a review of the evidenceNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 4 2001S. Sathasivam Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease primarily affecting the upper and lower motor neurones of the central nervous system. Recently, a lot of interest has been generated by the possibility that a mechanism of programmed cell death, termed apoptosis, is responsible for the motor neurone degeneration in this condition. Apoptosis is regulated through a variety of different pathways which interact and eventually lead to controlled cell death. Apart from genetic regulation, factors involved in the control of apoptosis include death receptors, caspases, Bcl-2 family of oncoproteins, inhibitor of apoptosis proteins (IAPs), inhibitors of IAPs, the p53 tumour suppressor protein and apoptosis-related molecules. The first part of this article will give an overview of the current knowledge of apoptosis. In the second part of this review, we will examine in detail the evidence for and against the contribution of apoptosis in motor neurone cell death in ALS, looking at cellular-, animal- and human post-mortem tissue-based models. In a chronic neurodegenerative disease such as ALS, conclusive evidence of apoptosis is likely to be difficult to detect, given the rapidity of the apoptotic cell death process in relation to the relatively slow time course of the disease. Although a complete picture of motor neurone death in ALS has not been fully elucidated, there is good and compelling evidence that a programmed cell death pathway operates in this disorder. The strongest body of evidence supporting this comes from the findings that, in ALS, changes in the levels of members of the Bcl-2 family of oncoproteins results in a predisposition towards apoptosis, there is increased expression or activation of caspases-1 and -3, and the dying motor neurones in human cases exhibit morphological features reminiscent of apoptosis. Further supporting evidence comes from the detection of apoptosis-related molecules and anti-Fas receptor antibodies in human cases of ALS. However, the role of the p53 protein in cell death in ALS is at present unclear. An understanding of the mechanism of programmed cell death in ALS may provide important clues for areas of potential therapeutic intervention for neuroprotection in this devastating condition. [source] Fast and faster: A designed variant of the B-domain of protein A folds in 3 ,secPROTEIN SCIENCE, Issue 4 2004Pooja Arora Abstract We have introduced the mutation glycine 29 to alanine, designed to increase the rate of protein folding, into the B-domain of protein A (BdpA). From NMR lineshape analysis, we find the G29A mutation increases the folding rate constant by threefold; the folding time is 3 ,sec. Although wild-type BdpA folds extremely fast, simple-point mutations can still speed up the folding; thus, the folding rate is not evolutionarily maximized. The short folding time of G29A BdpA (the shortest time yet reported) makes it an attractive candidate for an all-atom molecular dynamics simulation that could potentially show a complete folding reaction starting from an extended chain. We also constructed a fluorescent variant of BdpA by mutating phenylalanine 13 to tryptophan, allowing fluorescence-based time-resolved temperature-jump measurements. Temperature jumps and NMR complement each other, and give a very complete picture of the folding kinetics. [source] On the use of breakdown graphs combined with energy-dependent mass spectrometry to provide a complete picture of fragmentation processesRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 16 2002Colin P. G. Butcher Both breakdown graphs and energy-dependent (ED) maps provide a means of visually representing the fragmentation processes resulting from collision-induced dissociation at different energies. The two presentation methods may be combined for a complete picture of the appearance, disappearance and maximum abundance collision potentials of each of the ions involved in the fragmentation process. A demonstration of this approach is presented using two very different classes of compound, an amino acid and a transition metal carbonyl cluster. Copyright © 2002 John Wiley & Sons, Ltd. [source] Self-report quality of life as a predictor of hospitalization for patients with LV dysfunction: A life course approach,RESEARCH IN NURSING & HEALTH, Issue 6 2001Donald E. Stull Abstract For this secondary data analysis of a large clinical drug study, researchers investigated the independent prognostic utility of self-report quality-of-life measures versus clinical measures for assessing patient risk for heart-failure-related hospitalization. The experience of heart failure varies over the life course; hence, four age groups were investigated. Quality-of-life measures, specifically health-related quality-of-life and psychosocial quality-of-life measures, were found to be independent and significant predictors of heart-failure-related hospitalizations, as compared to traditional clinical indicators. In addition, the psychosocial quality-of-life measure varied by age group in its importance as a predictor of hospitalization, suggesting differential relevance over the life course. Specifically, psychosocial quality of life was most strongly predictive of hospitalization for those ages 21,44, was less predictive for those ages 45,54, and was nonsignificant for those 55,64 years of age and those 65 and over. Including self-report quality-of-life measures provides a more complete picture of the factors associated with risk of hospitalization at different points in the life course for individuals with heart failure. These findings suggest that researchers and practitioners could use self-report quality-of-life measures as additional prognostic indicators of a patient's condition and risk for heart-failure-related hospitalization, especially for younger patients. © 2001 John Wiley & Sons, Inc. Res Nurs Health 24:460,469, 2001 [source] Assessing reproductive profiles in female brown mouse lemurs (Microcebus rufus) from Ranomafana National Park, southeast Madagascar, using fecal hormone analysisAMERICAN JOURNAL OF PRIMATOLOGY, Issue 6 2009Marina B. Blanco Abstract Studies on reproductive endocrinology in wild primate populations have greatly increased in the last decades owing to the development of noninvasive techniques that can be applied under field conditions. However, small-bodied nocturnal species are not well represented on the long list of primates surveyed in the wild, and reproductive inferences regarding these animals in their natural habitats have not benefited from direct observations of hormonal changes. We collected fecal samples from female brown mouse lemurs (Microcebus rufus) in a southeastern rainforest of Madagascar in order to determine whether or not fecally excreted steroid levels show a consistent pattern of change during the reproductive season and are a useful complement to reproductive observations in wild-trapped individuals. Initial data show variation in reproductive hormone levels before and after estrus and estimated day of parturition. Elevated levels of excreted estradiol (E2) were observed around the time of estrus, whereas high levels of fecal progesterone (P) were seen during later stages of pregnancy and around parturition. A more complete picture of reproductive profiles in female mouse lemurs, and how they may change over the life span, can be obtained if hormone analyses are used to supplement field observations. Am. J. Primatol. 71:439,446, 2009. © 2009 Wiley-Liss, Inc. [source] The Woman behind Frey's Syndrome: The Tragic Life of Lucja FreyTHE LARYNGOSCOPE, Issue 12 2004Mirjam Moltrecht MD Abstract Objective: The auriculotemporal syndrome is known worldwide as Frey's syndrome. However, the Jewish physician Lucja Frey, after whom it was named, has fallen into obscurity. The little information about her is fragmentary, contradictory, and often incorrect. Study Design: To reconstruct the life of Lucja Frey, who was murdered by the Nazis in her native town if Lwów, it was imperative to look for original documents as irrevocable proof of her life. Methods: During this research, more than 100 archives and institutions in 8 countries have been contacted. Results: With the archive materials, it was possible for the first time to create a complete picture of the life of this fascinating physician. Furthermore, her day of death, unknown until now, could be determined with great plausibility. The lasting impression is not only of a tragic death under the Nazis but also of a tragic life as a whole. Conclusion: Lucja Frey would have been forgotten if not for the eponym Frey's syndrome. In this way, she is remembered not only as an unusual woman, physician, and scientist but also as one of millions of Jews murdered by the Nazis. This may be the only key remaining to prevent the repetition of one of the most haunting and devastating times in history. [source] The Idea of Socialism: From 1968 to the Present-day CrisisANTIPODE, Issue 2010Hugo Radice Abstract:, In 2008 the 40th anniversary of that iconic year, 1968, was celebrated in the media in relation to student uprisings and cultural revolts, largely neglecting the very significant movements of workers and peasants who were challenging power structures around the world at that time. This omission reflects the failures of socialism in the twentieth century, which are explored in this essay. Beginning from a more complete picture of 1968, the essay examines the history of socialism, identifying the main sources of failure in its theory and practice, in particular that of the revolutionary left. If the failure lies in the elite character of socialist politics and its focus on distribution rather than production, it is to be remedied by a firm focus on the politics of the workplace and the goal of substantive equality. The concluding section reviews the prospects for such an alternative in the current circumstances of global crisis. [source] On the Quantile Regression Based Tests for Asymmetry in Stock Return VolatilityASIAN ECONOMIC JOURNAL, Issue 2 2002Beum-Jo Park This paper attempts to examine whether the asymmetry of stock return volatility varies with the level of volatility. Thus, quantile regression based tests (,-tests) are presupposed. These tests differ from the diagnostic tests introduced by Engle and Ng (1993) insofar as they can provide a complete picture of asymmetries in volatility across quantiles of variance distribution and, in case of non-normal errors, they have improved power due to their robustness against non-normality. A small Monte Carlo evidence suggests that the Wald and likelihood ratio (LR) tests out of ,-tests are reasonable, showing that they outperform the Lagrange multiplier (LM) test based on least squares residuals when the innovations exhibit heavy tail. Using the normalized residuals obtained from AR(1)-GARCH(1, 1) estimation, the test results demonstrated that only the TOPIX out of six stock-return series had asymmetry in volatility at moderate level, while all stock return series except the FAZ and FA100 had more significant asymmetry in volatility at higher levels. Interestingly, it is clear from the empirical findings that, like hypothesis of leverage effects, volatility of the TOPIX, CAC40, and, MIB tends to respond significantly to extremely negative shock at high level, but is not correlated with any positive shock. These might be valuable findings that have not been seriously considered in past research, which has focussed only on mean level of volatility. [source] Realisation of a fully-deterministic microlensing observing strategy for inferring planet populations,ASTRONOMISCHE NACHRICHTEN, Issue 7 2010M. Dominik Abstract Within less than 15 years, the count of known planets orbiting stars other than the Sun has risen from none to more than 400 with detections arising from four successfully applied techniques: Doppler-wobbles, planetary transits, gravitational microlensing, and direct imaging. While the hunt for twin Earths is on, a statistically well-defined sample of the population of planets in all their variety is required for probing models of planet formation and orbital evolution so that the origin of planets that harbour life, like and including ours, can be understood. Given the different characteristics of the detection techniques, a complete picture can only arise from a combination of their respective results. Microlensing observations are well-suited to reveal statistical properties of the population of planets orbiting stars in either the Galactic disk or bulge from microlensing observations, but a mandatory requirement is the adoption of strictly-deterministic criteria for selecting targets and identifying signals. Here, we describe a fully-deterministic strategy realised by means of the ARTEMiS (Automated Robotic Terrestrial Exoplanet Microlensing Search) system at the Danish 1.54-m telescope at ESO La Silla between June and August 2008 as part of the MiNDSTEp (Microlensing Network for the Detection of Small Terrestrial Exoplanets) campaign, making use of immediate feedback on suspected anomalies recognized by the SIGNALMEN anomaly detector. We demonstrate for the first time the feasibility of such an approach, and thereby the readiness for studying planet populations down to Earth mass and even below, with ground-based observations. While the quality of the real-time photometry is a crucial factor on the efficiency of the campaign, an impairment of the target selection by data of bad quality can be successfully avoided. With a smaller slew time, smaller dead time, and higher through-put, modern robotic telescopes could significantly outperform the 1.54-m Danish, whereas lucky-imaging cameras could set new standards for high-precision follow-up monitoring of microlensing events (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||||||||||||||||||||||||||