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Terms modified by Substantial Selected AbstractsTaxon-specific variation in the stable isotopic signatures (,13C and ,15N) of lake phytoplanktonFRESHWATER BIOLOGY, Issue 5 2006KRISTIINA VUORIO Summary 1. The variability in the stable isotope signatures of carbon and nitrogen (,13C and ,15N) in different phytoplankton taxa was studied in one mesotrophic and three eutrophic lakes in south-west Finland. The lakes were sampled on nine to 16 occasions over 2,4 years and most of the time were dominated by cyanobacteria and diatoms. A total of 151 taxon-specific subsamples covering 18 different phytoplankton taxa could be isolated by filtration through a series of sieves and by flotation/sedimentation, followed by microscopical identification and screening for purity. 2. Substantial and systematic differences between phytoplankton taxa, seasons and lakes were observed for both ,13C and ,15N. The values of ,13C ranged from ,34.4, to ,5.9, and were lowest in chrysophytes (,34.4, to ,31.3,) and diatoms (,30.6, to ,26.6,). Cyanobacteria were most variable (,32.4, to ,5.9,), including particularly high values in the nostocalean cyanobacterium Gloeotrichia echinulata (,14.4, to ,5.9,). For ,13C, the taxon-specific amplitude of temporal changes within a lake was usually <1,8, (<1,4, for microalgae alone and <1,8, for cyanobacteria alone), whereas the amplitude among taxa within a water sample was up to 31,. 3. The values of ,15N ranged from ,2.1, to 12.8, and were high in chrysophytes, dinophytes and diatoms, but low in the nitrogen-fixing cyanobacteria Anabaena spp., Aphanizomenon spp. and G. echinulata (,2.1, to 1.6,). Chroococcalean cyanobacteria ranged from ,1.4, to 8.9,. For ,15N, the taxon-specific amplitude of temporal changes within a lake was 2,6,, (2,6, for microalgae alone and 2,4, for cyanobacteria alone) and the amplitude among taxa within a water sample was up to 11,. 4. The isotopic signatures of phytoplankton changed systematically with their physical and chemical environment, most notably with the concentrations of nutrients, but correlations were non-systematic and site-specific. 5. The substantial variability in the isotopic signatures of phytoplankton among taxa, seasons and lakes complicates the interpretation of isotopic signatures in lacustrine food webs. However, taxon-specific values and seasonal patterns showed some consistency among years and may eventually be predictable. [source] THE RESPONSE OF PARTIALLY DEBRIS-COVERED VALLEY GLACIERS TO CLIMATE CHANGE: THE EXAMPLE OF THE PASTERZE GLACIER (AUSTRIA) IN THE PERIOD 1964 TO 2006GEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 4 2008ANDREAS KELLERER-PIRKLBAUER ABSTRACT. Long-term observations of partly debris-covered glaciers have allowed us to assess the impact of supra-glacial debris on volumetric changes. In this paper, the behaviour of the partially debris-covered, 3.6 km2 tongue of Pasterze Glacier (47°05,N, 12°44,E) was studied in the context of ongoing climate changes. The right part of the glacier tongue is covered by a continuous supra-glacial debris mantle with variable thicknesses (a few centimetres to about 1 m). For the period 1964,2000 three digital elevation models (1964, 1981, 2000) and related debris-cover distributions were analysed. These datasets were compared with long-term series of glaciological field data (displacement, elevation change, glacier terminus behaviour) from the 1960s to 2006. Differences between the debriscovered and the clean ice parts were emphasised. Results show that volumetric losses increased by 2.3 times between the periods 1964,1981 and 1981,2000 with significant regional variations at the glacier tongue. Such variations are controlled by the glacier emergence velocity pattern, existence and thickness of supra-glacial debris, direct solar radiation, counter-radiation from the valley sides and their changes over time. The downward-increasing debris thickness is counteracting to a compensational stage against the common decrease of ablation with elevation. A continuous debris cover not less than 15 cm in thickness reduces ablation rates by 30,35%. No relationship exists between glacier retreat rates and summer air temperatures. Substantial and varying differences of the two different terminus parts occurred. Our findings clearly underline the importance of supra-glacial debris on mass balance and glacier tongue morphology. [source] Fire regimes of China: inference from statistical comparison with the United StatesGLOBAL ECOLOGY, Issue 5 2009Meg A. Krawchuk ABSTRACT Aim, Substantial overlap in the climate characteristics of the United States and China results in similar land-cover types and weather conditions, especially in the eastern half of the two countries. These parallels suggest similarities in fire regimes as well, yet relatively little is known about the historical role of fire in Chinese ecosystems. Consequently, we aimed to infer fire regime characteristics for China based on our understanding of climate,fire relationships in the United States. Location, The conterminous United States and the People's Republic of China. Methods, We used generalized additive models to quantify the relationship between reference fire regime classes adopted by the LANDFIRE initiative in the United States, and a global climate data set. With the models, we determined which climate variables best described the distribution of fire regimes in the United States then used these models to predict the spatial distribution of fire regimes in China. The fitted models were validated quantitatively using receiver operating characteristic area under the curve (AUC). We validated the predicted fire regimes in China by comparison with palaeoecological fire data and satellite-derived estimates of current fire activity. Results, Quantitative validation using the AUC indicated good discrimination of the distribution of fire regimes by models for the United States. Overall, fire regimes with more frequent return intervals were more likely in the east than in the west. The resolution of available historical and prehistorical fire data for China, including sediment cores, allowed only coarse, qualitative validation, but provided supporting evidence that fire has long been a part of ecosystem function in eastern China. MODIS satellite data illustrated that fire frequency within the last decade supported the classification of much of western China as relatively fire-free; however, much of south-eastern China experiences more fire activity than predicted with our models, probably as a function of the extensive use of fire by people. Conclusions, While acknowledging there are many cultural, environmental and historical differences between the United States and China, our fire regime models based on climate data demonstrate potential historical fire regimes for China, and propose that large areas of China share historical fire,vegetation,climate complexes with the United States. [source] A comparison of cyclic variations in anterior knee laxity, genu recurvatum, and general joint laxity across the menstrual cycleJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 11 2010Sandra J. Shultz Abstract Changes in anterior knee laxity (AKL), genu recurvatum (GR) and general joint laxity (GJL) were quantified across days of the early follicular and early luteal phases of the menstrual cycle in 66 females, and the similarity in their pattern of cyclic variations examined. Laxity was measured on each of the first 6 days of menses (M1,M6) and the first 8 days following ovulation (L1,L8) over two cycles. The largest mean differences were observed between L5 and L8 for AKL (0.32,mm), and between L5 and M1 for GR (0.56°) and GJL (0.26) (p,<,0.013). At the individual level, mean absolute cyclic changes in AKL (1.8,±,0.7,mm, 1.6,±,0.7,mm), GR (2.8,±,1.0°, 2.4,±,1.0°), and GJL (1.1,±,1.1, 0.7,±,1.0) were more apparent, with minimum, maximum and delta values being quite consistent from month to month (ICC2,3,=,0.51,0.98). Although the average daily pattern of change in laxity was quite similar between variables (Spearman correlation range 0.61 and 0.90), correlations between laxity measures at the individual level were much lower (range ,0.07 to 0.43). Substantial, similar, and reproducible cyclic changes in AKL, GR, and GJL were observed across the menstrual cycle, with the magnitude and pattern of cyclic changes varying considerably among females. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1411,1417, 2010 [source] Salicylic acid confers resistance to a biotrophic rust pathogen, Puccinia substriata, in pearl millet (Pennisetum glaucum)MOLECULAR PLANT PATHOLOGY, Issue 2 2009BRIDGET G. CRAMPTON SUMMARY Studies were undertaken to assess the induction of defence response pathways in pearl millet (Pennisetum glaucum) in response to infection with the leaf rust fungus Puccinia substriata. Pretreatment of pearl millet with salicylic acid (SA) conferred resistance to a virulent isolate of the rust fungus, whereas methyl jasmonate (MeJA) did not significantly reduce infection levels. These results suggest that the SA defence pathway is involved in rust resistance. In order to identify pearl millet genes that are specifically regulated in response to SA and not MeJA, and thus could play a role in resistance to P. substriata, gene expression profiling was performed. Substantial overlap in gene expression responses between the treatments was observed, with MeJA and SA treatments exhibiting 17% co-regulated transcripts. However, 34% of transcripts were differentially expressed in response to SA treatment, but not in response to MeJA treatment. SA-responsive transcripts represented genes involved in SA metabolism, defence response, signal transduction, protection from oxidative stress and photosynthesis. The expression profiles of pearl millet plants after treatment with SA or MeJA were more similar to one another than to the response during a compatible infection with P. substriata. However, some SA-responsive genes were repressed during P. substriata infection, indicating possible manipulation of host responses by the pathogen. [source] Substantial early, but nonprogressive neuronal loss in multiple sclerosis (ms) spinal cord,ANNALS OF NEUROLOGY, Issue 5 2009Lucas Schirmer MD Research in multiple sclerosis (MS) has recently been focusing on the extent of neuroaxonal damage and its contribution to disease outcome. In the present study, we examined spinal cord tissue from 30 clinically well-characterized MS patients. MS, amyotrophic lateral sclerosis (ALS), and control spinal cord tissue were subjected to morphometric analysis and immunohistochemistry for markers of cell damage and regeneration. Data were related to disease duration and age at death. Here, we present evidence for substantial, nonprogressive neuronal loss on the cervical and lumbar levels early in the disease course of MS. Chromatolytic neurons and immunoreactivity for c-Jun and GAP43 were observed in the ventral gray matter in and adjacent to actively demyelinating lesions, pointing toward neuronal damage and regeneration as an early response to lesion formation. Ann Neurol 2009;66:698,704 [source] Reviving a neglected celestial underwater polarization compass for aquatic animalsBIOLOGICAL REVIEWS, Issue 1 2006Talbot H. Waterman ABSTRACT Substantial in situ measurements on clear days in a variety of marine environments at depths in the water down to 200 m have demonstrated the ubiquitous daytime presence of sun-related e-vector (= plane of polarization) patterns. In most lines of sight the e-vectors tilt from horizontal towards the sun at angles equal to the apparent underwater refracted zenith angle of the sun. A maximum tilt-angle of approximately 48.5°, is reached in horizontal lines of sight at 90° to the sun's bearing (the plane of incidence). This tilt limit is set by Snell's window, when the sun is on the horizon. The biological literature since the 1980s has been pervaded with assumptions that daytime aquatic e-vectors are mainly horizontal. This review attempts to set the record straight concerning the potential use of underwater e-vectors as a visual compass and to reopen the field to productive research on aquatic animals' orientation and navigation. [source] Analysis of b -value calculations in diffusion weighted and diffusion tensor imagingCONCEPTS IN MAGNETIC RESONANCE, Issue 1 2005Daniel Güllmar Abstract Diffusion weighted imaging has opened new diagnostic possibilities by using microscopic diffusion of water molecules as a means of image contrast. The directional dependence of diffusion has led to the development of diffusion tensor imaging, which allows us to characterize microscopic tissue geometry. The link between the measured NMR signal and the self-diffusion tensor is established by the so-called b matrices that depend on the gradient's direction, strength, and timing. However, in the calculation of b -matrix elements, the influence of imaging gradients on each element of the b matrix is often neglected. This may cause errors, which in turn leads to an incorrect extraction of diffusion coefficients. In cases where the imaging gradients are high (high spatial resolution), these errors may be substantial. Using a generic pulsed gradient spin-echo (PGSE) imaging sequence, the effects of neglecting the imaging gradients on the b -matrix calculation are demonstrated. By measuring an isotropic phantom with this sequence it can be analytically as well as experimentally shown that large deviations in single b -matrix elements are generated. These deviations are obtained by applying the diffusion weighting in the readout direction of the imaging dimension in combination with relatively large imaging gradients. The systematic errors can be avoided by a full b -matrix calculation considering all the gradients of the sequence or by generating cross-term free signals using the geometric average of two diffusion weighted images with opposite polarity. The importance of calculating the exact b matrices by the proposed methods is based on the fact that more precise diffusion parameters are obtained for extracting correct property maps, such as fractional anisotropy, volume ratio, or conductivity tensor maps. © 2005 Wiley Periodicals, Inc. Concepts Magn Reson Part A 25A: 53,66, 2005 [source] Obstacles to Bottom-Up Implementation of Marine Ecosystem ManagementCONSERVATION BIOLOGY, Issue 5 2008KIRSTEN E. EVANS manejo de ecosistemas; manejo marino basado en ecosistemas; participación de partes interesadas; planificación de la conservación Abstract:,Ecosystem management (EM) offers a means to address multiple threats to marine resources. Despite recognition of the importance of stakeholder involvement, most efforts to implement EM in marine systems are the product of top-down regulatory control. We describe a rare, stakeholder-driven attempt to implement EM from the bottom up in San Juan County, Washington (U.S.A.). A citizens advisory group led a 2-year, highly participatory effort to develop an ecosystem-based management plan, guided by a preexisting conservation-planning framework. A key innovation was to incorporate social dimensions by designating both sociocultural and biodiversity targets in the planning process. Multiple obstacles hindered implementation of EM in this setting. Despite using a surrogate scheme, the information-related transaction costs of planning were substantial: information deficits prevented assessment of some biodiversity targets and insufficient resources combined with information deficits prevented scientific assessment of the sociocultural targets. Substantial uncertainty, practical constraints to stakeholder involvement, and the existence of multiple, potentially conflicting, objectives increased negotiation-related costs. Although information deficits and uncertainty, coupled with underinvestment in the transaction costs of planning, could reduce the long-term effectiveness of the plan itself, the social capital and momentum developed through the planning process could yield unforeseeable future gains in protection of marine resources. The obstacles we identified here will require early and sustained attention in efforts to implement ecosystem management in other grassroots settings. Resumen:,El manejo de ecosistemas es un medio para abordar múltiples amenazas a los recursos marinos. No obstante el reconocimiento de la importancia de la participación de las partes interesadas, la mayoría de los esfuerzos para implementar el manejo de ecosistemas en sistemas marinos son producto del control normativo de arriba hacia abajo. Describimos un intento raro, conducido por las partes interesadas, por implementar el manejo del ecosistema de abajo hacia arriba en el Condado San Juan, Washington (E.U.A.). Un grupo consultivo de ciudadanos dirigió un esfuerzo altamente participativo para desarrollar un plan de manejo basado en el ecosistema, guiados por un marco de planificación de la conservación preexistente. Una innovación clave fue la incorporación de dimensiones sociales al incluir objetivos tanto socioculturales como de biodiversidad en el proceso de planificación. Múltiples obstáculos dificultaron la implementación del manejo del ecosistema en este escenario. No obstante que se utilizó un plan sustituto, los costos de transacción de la planificación relacionados con la información fueron mayores de lo que el grupo pudo superar: los déficits de información impidieron la evaluación de algunos objetivos de biodiversidad y la insuficiencia de recursos combinada con los déficits de información impidieron la evaluación científica de los objetivos socioculturales. Los costos relacionados con la negociación incrementaron por la incertidumbre, por limitaciones prácticas en la participación de partes interesadas y la existencia de objetivos múltiples, potencialmente conflictivos. Aunque los déficits de información y la incertidumbre, aunados con la baja inversión en los costos de transacción de la planificación, pudieran reducir la efectividad a largo plazo del plan mismo, el capital social y el ímpetu desarrollados durante el proceso de planificación podrían producir ganancias futuras imprevisibles para la protección de recursos marinos. Los obstáculos que identificamos aquí requerirán de atención temprana y sostenida en los esfuerzos para implementar el manejo de ecosistemas en otros escenarios de base popular. [source] Genetic Effects of Multiple Generations of Supportive BreedingCONSERVATION BIOLOGY, Issue 6 2001Jinliang Wang This procedure is intended to increase population size without introducing exogenous genes into the managed population. Previous work examining the genetic effects of a single generation of supportive breeding has shown that although a successful program increases the census population size, it may reduce the genetically effective population size and thereby induce excessive inbreeding and loss of genetic variation. We expand and generalize previous analyses of supportive breeding and consider the effects of multiple generations of supportive breeding on rates of inbreeding and genetic drift. We derived recurrence equations for the inbreeding coefficient and coancestry, and thereby equations for inbreeding and variance effective sizes, under three models for selecting captive breeders: at random, preferentially among those born in captivity, and preferentially among those born in the wild. Numerical examples indicate that supportive breeding, when carried out successfully over multiple generations, may increase not only the census but also the effective size of the supported population as a whole. If supportive breeding does not result in a substantial and continuous increase of the census size of the breeding population, however, it might be genetically harmful because of elevated rates of inbreeding and genetic drift. Resumen: La práctica de apoyar poblaciones silvestres débiles mediante la captura de una fracción de los individuos silvestres, su cautiverio para la reproducción y la liberación a su descendencia en habitas naturales para que convivan con organismos silvestres se conoce como reproducción de apoyo y se ha empleado ampliamente en la biología de la conservación y en el manejo de pesca y vida silvestre. Este procedimiento tiene la intención de incrementar el tamaño de la población sin introducir genes exógenos en la población bajo manejo. Trabajos previos sobre los efectos genéticos de una sola generación de reproducción de apoyo muestran que, aunque un programa exitoso incrementa el tamaño poblacional, puede reducir la población genéticamente efectivae inducir así un exceso de consanguinidad y pérdida de variación genética. Expandimos y generalizamos análisis previos de la reproducción de apoyo y consideramos los efectos de múltiples generaciones de reproducción de soporte en las tasas de consanguinidad y de deriva génica. Derivamos ecuaciones de recurrencia para el coeficiente de consanguinidad y de coancestría, y por tanto ecuaciones de tamaños efectivos de consanguinidad y de varianza, para tres modelos de selección de reproductores en cautiverio : aleatoria, preferentemente entre los nacidos en cautiverio y preferentemente entre los nacidos en libertad. Los ejemplos numéricos indican que la reproducción de apoyo, cuando es exitosa en múltiples generaciones, puede ser favorable para el incremento no solo del tamaño, sino del tamaño efectivo de la población soportada en su conjunto. Sin embargo, si la reproducción de soporte no resulta en un incremento sustancial y continuo del tamaño de la población, puede ser genéticamente dañina debido a las altas tasas de consanguinidad y de deriva genética. [source] Gender differences in jail inmates' symptoms of mental illness, treatment history and treatment seeking,CRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 3 2009Amy L. Drapalski Background,Rates of mental illness among prisoners are substantial, but little is known about the unique mental health needs of women in jail, those under pre-trial custodial remand or serving short sentences. Aims,To compare male and female jail inmates along a wide range of symptoms of mental illness using identical assessment methods, and to examine gender differences in treatment seeking before and during incarceration. Methods,Soon after incarceration in a county jail, 360 male and 154 female pre-trial and post-trial inmates completed the Personality Assessment Inventory, a wide-ranging measure of psychiatric symptoms. Treatment seeking information was taken from official jail records. Results,Women were more likely to report clinically significant symptoms of anxiety, borderline personality features, somatic concerns and trauma-related symptoms; however, trauma-related symptoms and borderline features were also common among male inmates. Although both men and women reported high rates of drug-related problems, alcohol-related problems were twice as prevalent among male inmates. Female inmates were more likely to seek and be enrolled in jail-based treatment; there were no differences in reported help seeking prior to incarceration. Conclusions,Female jail inmates are especially in need of mental health services. Effective interventions for post-traumatic stress disorder and borderline personality disorder are needed in jail settings for both male and female inmates during incarceration and upon release. Copyright © 2009 John Wiley & Sons, Ltd. [source] PUBLIC PREFERENCES FOR REHABILITATION VERSUS INCARCERATION OF JUVENILE OFFENDERS: EVIDENCE FROM A CONTINGENT VALUATION SURVEY,CRIMINOLOGY AND PUBLIC POLICY, Issue 4 2006DANIEL S. NAGIN Research Summary: Accurately gauging the public's support for alternative responses to juvenile offending is important, because policy makers often justify expenditures for punitive juvenile justice reforms on the basis of popular demand for tougher policies. In this study, we assess public support for both punitively and nonpunitively oriented juvenile justice policies by measuring respondents' willingness to pay for various policy proposals. We employ a methodology known as "contingent valuation" (CV) that permits the comparison of respondents' willingness to pay (WTP) for competing policy alternatives. Specifically, we compare CV-based estimates for the public's WTP for two distinctively different responses to serious juvenile crime: incarceration and rehabilitation. An additional focus of our analysis is an examination of the public's WTP for an early childhood prevention program. The analysis indicates that the public is at least as willing to pay for rehabilitation as punishment for juvenile offenders and that WTP for early childhood prevention is also substantial. Implications and future research directions are outlined. Policy Implications: The findings suggest that lawmakers should more actively consider policies grounded in rehabilitation, and, perhaps, be slower to advocate for punitive reforms in response to public concern over high-profile juvenile crimes. Additionally, our willingness to pay findings offer encouragement to lawmakers who are uncomfortable with the recent trend toward punitive juvenile justice policies and would like to initiate more moderate reforms. Such lawmakers may be reassured that the public response to such initiatives will not be hostile. Just as importantly, reforms that emphasize leniency and rehabilitation can be justified economically as welfare-enhancing expenditures of public funds. The evidence that the public values rehabilitation more than increased incarceration should be important information to cost-conscious legislators considering how to allocate public funds. Cost-conscious legislatures may become disenchanted with punitive juvenile justice policies on economic grounds and pursue policies that place greater emphasis on rehabilitation. They may be reassured, on the basis of our findings, that the public will support this move. [source] THE CRIME-CONTROL EFFECT OF INCARCERATION: DOES SCALE MATTER?,CRIMINOLOGY AND PUBLIC POLICY, Issue 2 2006RAYMOND V. LIEDKA Research Summary: Several prominent empirical studies estimate models of a constant proportional effect of prison on crime, finding that effect is substantial and negative. A separate literature argues against the crime-reducing effect of prison but mainly on theoretical grounds. This second literature suggests that the elasticity of the prison/crime relationship is not constant. We provide a model that nests these two literatures. Using data from the United States over 30 years, we find strong evidence that the negative relationship between prison and crime becomes less strongly negative as the scale of imprisonment increases. This revisionist model indicates that (1) at low levels of incarceration, a constant elasticity model underestimates the negative relationship between incarceration and crime, and (2) at higher levels of incarceration, the constant elasticity model overstates the negative effect. Policy Implications: These results go beyond the claim of declining marginal returns, instead finding accelerating declining marginal returns. As the prison population continues to increase, albeit at a slower rate, after three decades of phenomenal growth, these findings provide an important caution that for many jurisdictions, the point of accelerating declining marginal returns may have set in. Any policy discussion of the appropriate scale of punishment should be concerned with the empirical impact of this expensive and intrusive government intervention. [source] Cytoplasmic fatty acid-binding protein facilitates fatty acid utilization by skeletal muscleACTA PHYSIOLOGICA, Issue 4 2003J. F. C. Glatz Abstract The intracellular transport of long-chain fatty acids in muscle cells is facilitated to a great extent by heart-type cytoplasmic fatty acid-binding protein (H-FABP). By virtue of the marked affinity of this 14.5-kDa protein for fatty acids, H-FABP dramatically increases their concentration in the aqueous cytoplasm by non-covalent binding, thereby facilitating both the transition of fatty acids from membranes to the aqueous space and their diffusional transport from membranes (e.g. sarcolemma) to other cellular compartments (e.g. mitochondria). Striking features are the relative abundance of H-FABP in muscle, especially in oxidative muscle fibres, and the modulation of the muscular H-FABP content in concert with the modulation of other proteins and enzymes involved in fatty acid handling and utilization. Newer studies with mice carrying a homozygous or heterozygous deletion of the H-FABP gene show that, in comparison with wild-type mice, hindlimb muscles from heterozygous animals have a markedly lowered (,66%) H-FABP content but unaltered palmitate uptake rate, while in hindlimb muscles from homozygous animals (no H-FABP present) palmitate uptake was reduced by 45%. These findings indicate that H-FABP is present in relative excess and plays a substantial, but merely permissive role in fatty acid uptake by skeletal muscles. [source] Screening for the 21st century: learning from the pastCYTOPATHOLOGY, Issue 1 2000A. E. Raffle Introduction In 1986 I took on the public health responsibility for the cervical screening service in Avon. Like many others, I understood screening to be a simple, highly effective, and inexpensive way of stopping people getting cancer. The only problem so far as I was aware was in making sure those most at risk took up the opportunity to be screened. The more involved I became with screening, however, the more I was obliged to modify this view. In summary, I was confronted with two problems. The Avon cervical screening service,thanks to contributions from many individuals over the previous two decades,was already well organized and population coverage was already high. Why then were women still dying from cancer of the cervix? Why also was there a substantial and rising number of women requiring colposcopic investigation for screen-detected abnormality when, according to screening theory, the ,prevalence' pool should have been cleared and the rate of newly detected ,incident' abnormalities should equate to the incidence of serious disease? [source] The Impact of E-Replenishment Strategy on Make-to-Order Supply Chain PerformanceDECISION SCIENCES, Issue 1 2005E. Powell Robinson Jr. ABSTRACT This research investigates the impact of electronic replenishment strategy on the operational activities and performance of a two-stage make-to-order supply chain. We develop simulation-based rolling schedule procedures that link the replenishment processes of the channel members and apply them in an experimental analysis to study manual, semi-automated, and fully automated e-replenishment strategies in decentralized and coordinated decision-making supply chain structures. The average operational cost reductions for moving from a manual-based system to a fully automated system are 19.6, 29.5, and 12.5%, respectively, for traditional decentralized, decentralized with information sharing, and coordinated supply chain structures. The savings are neither equally distributed among participants, nor consistent across supply chain structures. As expected, for the fully coordinated system, total costs monotonically decrease with higher levels of automation. However, for the two decentralized structures, under which most firms operate today, counter-intuitive findings reveal that the unilateral application of e-procurement technology by the buyer may lower his purchasing costs, but increase the seller's and system's costs. The exact nature of the relationship is determined by the channel's operational flexibility. Broader results indicate that while the potential economic benefit of e-replenishment in a decentralized system is substantial, greater operational improvements maybe possible through supply chain coordination. [source] Generalized anxiety disorder with and without excessive worry in Hong KongDEPRESSION AND ANXIETY, Issue 10 2009Sing Lee M.B.B.S. Abstract Background: Two previous U.S. studies found that although generalized anxiety disorder (GAD) without self-perceived excessive worry was milder than GAD with excessive worry, its persistence, impairment, and risk for subsequent onset of other mental disorders were still substantial. This study examined the implications of relaxing the "excessiveness" criterion on the prevalence and socio-demographic profile of GAD in a Chinese population sample by considering both self and others' perception of excessive worry. Method: 2,005 respondents aged 15,65 years participated in a structured telephone interview that covered socio-demographic profile, 12-month DSM-IV diagnosis of GAD, core depressive symptoms, longest duration of worry episode, number of domains of worry, impairment measured by the Sheehan Disability Scale, and treatment-seeking. Excessive worry was assessed from the perception of both respondents and others as reported by respondents. Result: The 12-month prevalence of GAD increased from 3.4 to 4% when the excessiveness requirement was relaxed. Excessive GAD and nonexcessive GAD had similar socio-demographic, symptom, chronicity, impairment, depressive symptom, and treatment-seeking profiles. Conclusion: GAD without excessive worry was less common than GAD with excessive worry but was likely to be a valid nosological entity. Future iterations of the DSM-IV should clarify whether excessive worry should be retained and, if so, how individuals who only reported excessive worries perceived by others should be optimally assessed. Depression and Anxiety, 2009. © 2009 Wiley-Liss, Inc. [source] Errors in the Interpretation of Mohs Histopathology Sections Over a 1-Year FellowshipDERMATOLOGIC SURGERY, Issue 12 2008MICHAEL E. MURPHY MD BACKGROUND Errors can occur in the interpretation of Mohs histopathology sections. Errors in histology interpretation can lead to incomplete removal of cancer and cancer persistence or the unnecessary removal of uninvolved tissue. Extensive proctored training is necessary to reduce these errors to an absolute minimum level. OBJECTIVE To analyze and quantify the number of cases and the amount of time required to reach a satisfactory level of expertise in the reading and interpretation of Mohs histopathology. METHODS A single-institution pilot study was designed to track errors in the interpretation and mapping of Mohs histopathology sections. A Mohs surgery fellow independently preread Mohs cases and rendered his interpretation on the Mohs map. One of the Mohs program directors subsequently reviewed and corrected all cases. Errors were scored on a graded scale and tracked over the 1-year fellowship to determine the number of cases and amount of time necessary to reduce errors to a baseline minimal level. RESULTS One thousand four hundred ninety-one Mohs surgery cases were required to generate 1,347 pathology specimens for review and grading over 6 months of Mohs surgery fellowship before reducing errors to a minimum acceptable level of less than 1 critical error per 100 cases read. CONCLUSIONS The number of cases and time required to reduce errors in the interpretation of Mohs histology is substantial. Direct and immediate mentored correction of errors is essential for improvement. These results can act as a guide for Mohs surgery training programs to help determine the minimum number of directly proctored cases required to obtain expertise in this crucial component of Mohs surgery. [source] Trends in Pediatric Melanoma Mortality in the United States, 1968 through 2004DERMATOLOGIC SURGERY, Issue 2 2008KEVAN G. LEWIS MD BACKGROUND AND OBJECTIVE Mortality from melanoma in children is a poorly understood and controversial problem in dermatology. There is paucity of research into this important public health dilemma. The purpose of this study was to characterize pediatric melanoma mortality in the United States and to evaluate trends over time. METHODS AND MATERIALS Deaths were derived from a database of more than 75 million records of the U.S. Center for National Health Statistics based on routine death certification. Information on age, race, gender, and geographic location was available for years 1968 through 2004. RESULTS During the 37-year period, there were 643 deaths attributed to melanoma in children under 20 years of age in the United States, an average of 18 per year. The overall age-adjusted mortality rate for melanoma in children was 2.25 deaths per year (per 10 million at-risk individuals). Mortality rates were strongly associated with age. In the oldest age group (age 15,19 years) the mortality rate was approximately an order of magnitude 8,18 times higher compared to younger age groups. Mortality among males was 25% higher than females. Mortality rates for white children were more than twice as high as black children. Overall mortality from melanoma in children declined steadily from 1968 to 2004. The highest mortality rates were observed in Idaho, Nevada, Arizona, and New Mexico. CONCLUSIONS Although mortality from melanoma among children in the United State is low, the magnitude of the public health burden from this preventable cause of death is substantial. In contrast to results of studies suggesting that the incidence of melanoma may be rising in children and adolescents, the data suggest that mortality in these groups may be falling. Additional study is warranted to further characterize and ultimately reduce mortality from childhood melanoma. [source] Results of a Survey of 5,700 Patient Monopolar Radiofrequency Facial Skin Tightening Treatments: Assessment of a Low-Energy Multiple-Pass Technique Leading to a Clinical End Point AlgorithmDERMATOLOGIC SURGERY, Issue 8 2007FRCP, FRCPC, JEFFREY S. DOVER MD INTRODUCTION Monopolar radiofrequency is an effective means of nonsurgical facial skin tightening. OBJECTIVE The objective of this study was to determine whether using larger tips at lower energy and multiple passes, using patient feedback on heat sensation and treating to a clinical end point of visible tightening, would yield better results than single passes with small tips at high energy, as measured by patient and physician satisfaction. METHODS Fourteen physicians from four specialties were surveyed to determine the answers to the following three questions. (1) Is patient's feedback on heat sensation a valid and preferred method for optimal energy selection? (2) Do multiple passes at moderate energy settings yield substantial and consistent efficacy? (3) Is treating to a clinical end point of visible tightening predictable of results? RESULTS A total of 5,700 patient treatments were surveyed. Comparisons were made using the original algorithm of high-energy, single pass to the new algorithm of lower energy and multiple passes with visible tightening as the end point of treatment. Using the original treatment algorithm, 26% of patients demonstrated immediate tightening, 54% observed skin tightening 6 months after treatment, 45% found the procedure too painful, and 68% of patients found the treatment results met their expectations. With the new multiple-pass algorithm, 87% observed immediate tightening, 92% had the tightening six months after treatment, 5% found the procedure too painful, while 94% found the treatment results met their expectations. CONCLUSIONS Patient feedback on heat sensation is a valid, preferable method for optimal energy selection in monopolar radiofrequency skin-tightening treatments. [source] Interobserver reliability of visual interpretation of electroencephalograms in children with newly diagnosed seizuresDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 5 2006Hans Stroink MD The reliability of visual interpretation of electroencephalograms (EEG) is of great importance in assessing the value of this diagnostic tool. We prospectively obtained 50 standard EEGs and 61 EEGs after partial sleep deprivation from 93 children (56 males, 37 females) with a mean age of 6 years 10 months (SE 5mo; range 4mo,15y 7mo) with one or more newly diagnosed, unprovoked seizures. Two clinical neurophysiologists independently classified the background pattern and the presence of epileptiform discharges or focal non-epileptiform abnormalities of each EEG. The agreement was substantial for the interpretation of the EEG as normal or abnormal (kappa 0.66), almost perfect for the presence of epileptiform discharges (kappa 0.83), substantial for the occurrence of an abnormal background pattern (kappa 0.73), and moderate for the presence of focal non-epileptiform discharges (kappa 0.54). In conclusion, the reliability of the visual interpretation of EEGs in children is almost perfect as regards the presence of epileptiform abnormalities, and moderate to substantial for the presence of other abnormalities. [source] Prenatal stress causes dendritic atrophy of pyramidal neurons in hippocampal CA3 region by glutamate in offspring ratsDEVELOPMENTAL NEUROBIOLOGY, Issue 2 2010Ning Jia Abstract A substantial number of human epidemiological data, as well as experimental studies, suggest that adverse maternal stress during gestation is involved in abnormal behavior, mental, and cognition disorder in offspring. To explore the effect of prenatal stress (PS) on hippocampal neurons, in this study, we observed the dendritic field of pyramidal neurons in hippocampal CA3, examined the concentration of glutamate (Glu), and detected the expression of synaptotagmin-1 (Syt-1) and N -methyl- D -aspartate receptor 1 (NR1) in hippocampus of juvenile female offspring rats. Pregnant rats were divided into two groups: control group (CON) and PS group. Female offspring rats used were 30-day old. The total length of the apical dendrites of pyramidal neurons in hippocampal CA3 of offspring was significantly shorter in PS than that in CON (p < 0.01). The number of branch points of the apical dendrites of pyramidal neurons in hippocampal CA3 of offspring was significantly less in PS (p < 0.01). PS offspring had a higher concentration of hippocampal Glu compared with CON (p < 0.05). PS offspring displayed increased expression of Syt-1 and decreased NR1 in hippocampus compared with CON (p < 0.001 and p < 0.01, respectively). The expression of NR1 in different hippocampus subfields of offspring was significantly decreased in PS than that in CON (p < 0.05-0.01). This study shows that PS increases the Glu in hippocampus and causes apical dendritic atrophy of pyramidal neurons of hippocampal CA3 in offspring rats. The decline of NR1 in hippocampus may be an adaptive response to the increased Glu. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2010 [source] Psychiatric services for people with severe mental illness across western Europe: what can be generalized from current knowledge about differences in provision, costs and outcomes of mental health care?ACTA PSYCHIATRICA SCANDINAVICA, Issue 2006T. Becker Objective:, To report recent findings regarding differences in the provision, cost and outcomes of mental health care in Europe, and to examine to what extent these studies can provide a basis for improvement of mental health services and use of findings across countries. Method:, Findings from a number of studies describing mental health care in different European countries and comparing provision of care across countries are reported. Results:, The development of systems of mental health care in western Europe is characterized by a common trend towards deinstitutionalization, less in-patient treatment and improvement of community services. Variability between national mental healthcare systems is still substantial. At the individual patient level the variability of psychiatric service systems results in different patterns of service use and service costs. However, these differences are not reflected in outcome differences in a coherent way. Conclusion:, It is conceivable that the principal targets of mental healthcare reform can be achieved along several pathways taking into account economic, political and sociocultural variation between countries. Differences between mental healthcare systems appear to affect service provision and costs. However, the impact of such differences on patient outcomes may be less marked. The empirical evidence is limited and further studies are required. [source] Adaptive training leads to sustained enhancement of poor working memory in childrenDEVELOPMENTAL SCIENCE, Issue 4 2009Joni Holmes Working memory plays a crucial role in supporting learning, with poor progress in reading and mathematics characterizing children with low memory skills. This study investigated whether these problems can be overcome by a training program designed to boost working memory. Children with low working memory skills were assessed on measures of working memory, IQ and academic attainment before and after training on either adaptive or non-adaptive versions of the program. Adaptive training that taxed working memory to its limits was associated with substantial and sustained gains in working memory, with age-appropriate levels achieved by the majority of children. Mathematical ability also improved significantly 6 months following adaptive training. These findings indicate that common impairments in working memory and associated learning difficulties may be overcome with this behavioral treatment. [source] RD Lawrence Lecture 2009 Old genes, new tricks: learning about blood glucose regulation from naturally occurring genetic variation in humansDIABETIC MEDICINE, Issue 11 2009A. L. Gloyn Abstract The study of rare monogenic forms of diabetes and pancreatic B-cell dysfunction provides an unrivalled opportunity to link a specific change in gene function with precise cellular consequences and clinical phenotype in humans. Over the past 20 years there has been considerable success in determining the genetic aetiology of a number of rare monogenic forms of diabetes, which has had a significant impact on both our understanding of normal physiology and on translational medicine. The impact of these discoveries has been substantial, with insights into both developmental biology and normal physiology. There are clear examples where determining the genetic aetiology for individuals with rare monogenic subtypes of diabetes has led to improved treatment. Although formerly in the shadow of the monogenic diabetes field, over the past 3 years there has been staggering progress in our understanding of the genetic basis of Type 2 diabetes. This has been largely as a result of genome-wide association studies and has seen the list of ,diabetes susceptibility genes' increase from three to close to 20. There is now encouraging evidence to support a potential role for genetics in determining the response of individuals with Type 2 diabetes to different therapeutic options. One of the challenges that lies ahead is determining how the non-coding genetic variants exert their pathogenicity. It is possible that parallels can be drawn from functional work on rare regulatory mutations causing monogenic forms of diabetes. However, it is more likely that comprehensive approaches will be necessary. [source] Interobserver agreement between primary graders and an expert grader in the Bristol and Weston diabetic retinopathy screening programme: a quality assurance auditDIABETIC MEDICINE, Issue 8 2009S. Patra Abstract Aims, To assess the quality and accuracy of primary grading in the Bristol and Weston diabetic retinopathy screening programme and to set standards for future interobserver agreement reports. Methods, A prospective audit of 213 image sets from six fully trained primary graders in the Bristol and Weston diabetic retinopathy screening programme was carried out over a 4-week period. All the images graded by the primary graders were regraded by an expert grader blinded to the primary grading results and the identity of the primary grader. The interobserver agreement between primary graders and the blinded expert grader and the corresponding Kappa coefficient was determined for overall grading, referable, non-referable and ungradable disease. The audit standard was set at 80% for interobserver agreement with a Kappa coefficient of 0.7. Results, The interobserver agreement bettered the audit standard of 80% in all the categories. The Kappa coefficient was substantial (0.7) for the overall grading results and ranged from moderate to substantial (0.59,0.65) for referable, non-referable and ungradable disease categories. The main recommendation of the audit was to provide refresher training for the primary graders with focus on ungradable disease. Conclusion, The audit demonstrated an acceptable level of quality and accuracy of primary grading in the Bristol and Weston diabetic retinopathy screening programme and provided a standard against which future interobserver agreement can be measured for quality assurance within a screening programme. [source] The European perspective of psychiatric reformACTA PSYCHIATRICA SCANDINAVICA, Issue 2001T. Becker Objective:,To provide a framework of mental health care reform across Europe. Method:,On the basis of summary quantitative indices and expert ratings of broad aspects of mental health care structure, the process and outcome of psychiatric reform common trends and differences are outlined. Results:,There has been a broad trend away from an institutional model of care with the mental hospital as the dominant institution, and community- and general hospital-based mental health services of varying comprehensiveness are in place in most countries. The social and broad community aspects of psychiatric reform have generally been somewhat less successful than changes in service set-up. Assessment of reform outcomes proves particularly difficult. Conclusion:,Psychiatric reform processes have achieved some of their aims, and there are broadly similar trends. Regional variation is substantial and may be as important as cross-national differences. Mental health care reform is ongoing across the European region. [source] The Application of Geographic Information Systems and Global Positioning Systems in Humanitarian Emergencies: Lessons Learned, Programme Implications and Future ResearchDISASTERS, Issue 2 2003Reinhard Kaiser Geographic information systems (GIS), global positioning systems and remote sensing have been increasingly used in public health settings since the 1990s, but application of these methods in humanitarian emergencies has been less documented. Recent areas of application of GIS methods in humanitarian emergencies include hazard, vulnerability, and risk assessments; rapid assessment and survey methods; disease distribution and outbreak investigations; planning and implementation of health information systems; data and programme integration; and programme monitoring and evaluation. The main use of GIS in these areas is to provide maps for decision-making and advocacy, which allow overlaying types of information that may not normally be linked. GIS is also used to improve data collection in the field (for example, for rapid health assessments or mortality surveys). Development of GIS methods requires further research. Although GIS methods may save resources and reduce error, initial investment in equipment and capacity building may be substantial. Especially in humanitarian emergencies, equipment and methodologies must be practical and appropriate for field use. Add-on software to process GIS data needs to be developed and modified. As equipment becomes more user-friendly and costs decrease, GIS will become more of a routine tool for humanitarian aid organisations in humanitarian emergencies, and new and innovative uses will evolve. [source] Elevated dominance of extrafloral nectary-bearing plants is associated with increased abundances of an invasive ant and reduced native ant richnessDIVERSITY AND DISTRIBUTIONS, Issue 5 2009Amy M. Savage Abstract Aim, Invasive ants can have substantial and detrimental effects on co-occurring community members, especially other ants. However, the ecological factors that promote both their population growth and their negative influences remain elusive. Opportunistic associations between invasive ants and extrafloral nectary (EFN)-bearing plants are common and may fuel population expansion and subsequent impacts of invasive ants on native communities. We examined three predictions of this hypothesis, compared ant assemblages between invaded and uninvaded sites and assessed the extent of this species in Samoa. Location, The Samoan Archipelago (six islands and 35 sites). Methods, We surveyed abundances of the invasive ant Anoplolepis gracilipes, other ant species and EFN-bearing plants. Results,Anoplolepis gracilipes was significantly more widely distributed in 2006 than in 1962, suggesting that the invasion of A. gracilipes in Samoa has progressed. Furthermore, (non- A. gracilipes) ant assemblages differed significantly between invaded and uninvaded sites. Anoplolepis gracilipes workers were found more frequently at nectaries than other plant parts, suggesting that nectar resources were important to this species. There was a strong, positive relationship between the dominance of EFN-bearing plants in the community and A. gracilipes abundance on plants, a relationship that co-occurring ants did not display. High abundances of A. gracilipes at sites dominated by EFN-bearing plants were associated with low species richness of native plant-visiting ant species. Anoplolepis gracilipes did not display any significant relationships with the diversity of other non-native ants. Main conclusions, Together, these data suggest that EFN-bearing plants may promote negative impacts of A. gracilipes on co-occurring ants across broad spatial scales. This study underscores the potential importance of positive interactions in the dynamics of species invasions. Furthermore, they suggest that conservation managers may benefit from explicit considerations of potential positive interactions in predicting the identities of problematic invaders or the outcomes of species invasions. [source] A systematic review of the effectiveness of brief interventions with substance using adolescents by type of drugDRUG AND ALCOHOL REVIEW, Issue 3 2003Dr ROBERT J. TAIT Abstract The aim of this paper is to evaluate the effectiveness of brief interventions (BI) with adolescents (mean age < 20) in reducing alcohol, tobacco or other drug (ATOD) use by means of a systematic review of BI for adolescent substance use in the English language literature up to 2002. We identified 11 studies involving 3734 adolescents. Follow-up ranged from 6 weeks to 24 months. Motivational interviewing was the predominant approach, underpinning eight studies: the remaining three provided personalized health information. Seven papers reported outcomes for alcohol interventions and four involved other substances (including one with separate alcohol outcomes). The overall effect size was d= 0.126 with borderline homogeneity (Q = 14.9, df = 9, p = 0.09). The effect size from the eight alcohol interventions (n = 1075) was classified as significant but "small" (d = 0.275). The remaining non-alcohol studies were considered separately as interventions involving tobacco or multiple substance use. The two interventions with tobacco involved a substantial sample (n = 2626) but had a very small effect (d = 0.037), while the two interventions addressing multiple substances involved few participants (n = 110) but had a medium , large effect (d = 0.78). Across a diverse range of settings (dental clinic, schools, universities, substance treatment centres) and, therefore, probably diverse clients, BI conferred benefits to adolescent substance users. BI had a small effect on alcohol consumption and related measures. The data for tobacco interventions suggested a very small reduction, particularly with general community interventions. The effect of BI with multiple substances appears substantial but the small sample cautions against expansive generalization. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||