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Selected AbstractsRapid steroid discontinuation for pediatric renal transplantation: A single center experiencePEDIATRIC TRANSPLANTATION, Issue 5 2007Keith K. Lau Abstract:, To determine the outcomes of pediatric renal transplant recipients who received immunosuppression consisting of early withdrawal of corticosteroids at a single Northern California center. Protocols using minimal steroid exposure have been recently reported in adult transplant recipients with successful results. We examined the outcomes of pediatric renal transplant recipients who were managed at our center using a protocol with very early discontinuation of steroids after renal transplantation. We retrospectively studied the medical records of all renal transplant recipients followed at the Children's Hospital at the University of California, Davis Medical Center from 01/2004 to 12/2005. All patients were less than 18 yr of age at the time of transplantation. The immunosuppressive protocol included three tapering daily doses of methylprednisolone, together with five doses of thymoglobulin followed by maintenance therapy with tacrolimus and MMF. Eight patients with equal numbers of males and females were transplanted during this time period. There were equal numbers of Caucasians, African-Americans, Hispanics, and Asians. A total of 37.5% (3/8) of the subjects received preemptive transplantation, 25% (2/8) received peritoneal, and 37.5% (3/8) received hemodialysis before transplantation. The median (range) age at transplantation was 12.3 (3.1,16.0) year with a follow-up of 1.7 (0.9,2.8) year. At one yr post-transplantation, 57% (4/7) of patients still required anti-hypertensives. Three children required erythropoietin supplementation after transplantation. The mean delta height standard deviation score at 12 months was 0.20 ± 0.56. There were no episodes of clinical acute rejection. One patient switched from tacrolimus to sirolimus due to biopsy-proven CAN. No patient became diabetic or required hypoglycemic agents. Surveillance biopsies showed no subclinical acute rejection in any patient. Steroid-free immunosuppression is safe in children after renal transplantation. Larger number of patients and longer follow-up are required to further confirm the effectiveness and safety of immunosuppression with rapid steroid discontinuation. [source] A review of evaluation outcomes of web-based continuing medical educationMEDICAL EDUCATION, Issue 6 2005Vernon R Curran Introduction, The Internet and worldwide web have expanded opportunities for the provision of a flexible, convenient and interactive form of continuing medical education (CME). Larger numbers of doctors are accessing and using the Internet to locate and seek medical information. It has been suggested that a significant proportion of this usage is directly related to questions that arise from patient care. A variety of Internet technologies are being used to provide both asynchronous and synchronous forms of web-based CME. Various models for designing and facilitating web-based CME learning have also been reported. The purpose of this study was to examine the nature and characteristics of the web-based CME evaluative outcomes reported in the peer-reviewed literature. Methods, A search of Medline was undertaken and the level of evaluative outcomes reported was categorised using Kirkpatrick's model for levels of summative evaluation. Results, The results of this analysis revealed that the majority of evaluative research on web-based CME is based on participant satisfaction data. There was limited research demonstrating performance change in clinical practices and there were no studies reported in the literature that demonstrated that web-based CME was effective in influencing patient or health outcomes. Discussion, The findings suggest an important need to examine in greater detail the nature and characteristics of those web-based learning technologies, environments and systems which are most effective in enhancing practice change and ultimately impacting patient and health outcomes. This is particularly important as the Internet grows in popularity as a medium for knowledge transfer. [source] Bushmeat Markets on Bioko Island as a Measure of Hunting PressureCONSERVATION BIOLOGY, Issue 6 2000John E. Fa Comparisons of the availability and abundance of individual species between years showed that more species and more carcasses appeared in 1996 than in 1991. In biomass terms, the increase was significantly less, only 12.5%, when compared with almost 60% more carcasses entering the market in 1996. A larger number of carcasses of the smaller-bodied species (i.e., rodents and the blue duiker [Cephalophus monticola] ) were recorded in 1996 than in 1991. Although an additional four species of birds and one squirrel were recorded in 1996, these were less important in terms of their contribution to biomass or carcass numbers. Concurrently, there was a dramatic reduction in the larger-bodied species, Ogilby's duiker (C. ogilbyi) and seven diurnal primates. We examined these changes, especially the drop in the number of larger animals. We considered the possible following explanations: (1) the number of hunters dropped either because of enforced legislation or scarcity of larger prey; (2) a shift in the use of hunting techniques occurred ( from shotguns to snares); or (3) consumer demand for primate and duiker meat dropped, which increased demand for smaller game. Our results suggest that the situation in Bioko may be alarmingly close to a catastrophe in which primate populations of international conservation significance are being hunted to dangerously low numbers. Although there is still a need for surveys of actual densities of prey populations throughout the island, working with the human population on Bioko to find alternatives to bushmeat is an urgent priority. Resumen: Realizamos conteos de los cuerpos de animales llevados al mercado de Malabo, en la Isla Bioko, Guinea Ecuatorial, durante dos periodos de estudio de ocho meses cada uno en 1991 y 1996. Las comparaciones realizadas de la disponibilidad y abundancia de especies individuales entre estos años mostró que más especies y más cuerpos aparecieron en 1996 que en 1991. En términos de biomasa, el incremento fue significativamente menor, solo 12.5% cuando se comparó con un incremento de casi un 60% más de cuerpos que llegaron al mercado en 1996. Se observó un mayor número de cuerpos de especies de tamaño pequeño ( por ejemplo roedores, y el duiker azul, Cephalophus monticola) en 1996 que en 1991. A pesar de que hubo una adición de cuatro especies de aves y una especie de ardilla en 1996, estas fueron menos importantes en cuanto a su contribución a la biomasa o el número de cuerpos. Al mismo tiempo, hubo una reducción dramática de especies de cuerpo grande, el duiker de Ogilby (C. ogilbyi) y siete primates diurnos. Examinamos estos cambios, especialmente la caída en el número de animales grandes y consideramos las siguientes posibles explicaciones: (1) hubo una caída significativa en el número de cazadores debido a la posible ejecución de la legislación o debido a una escasez de presas grandes; (2) hubo un cambio en el uso de técnicas de caza ( por ejemplo, el reemplazo de armas de fuego por trampas); o (3) la demanda del consumidor por carne de primates y duikers disminuyó, incrementándose la demanda por animales pequeños. Nuestros resultados sugieren que la situación en Bioko puede estar alarmantemente cerca de una catástrofe en la cual las poblaciones de primates, que son de gran significado para la conservación internacional, han sido reducidas a niveles peligrosamente bajos. A pesar de que aún se necesita llevar a cabo estudios de las densidades existentes de poblaciones de presas a lo largo de la isla, es urgente trabajar con la población humana de Bioko para encontrar alternativas a la venta de carne silvestre. [source] Combined Ultrapulse CO2 Laser and Q-Switched Alexandrite Laser Compared with Q-Switched Alexandrite Laser Alone for Refractory Melasma: Split-Face DesignDERMATOLOGIC SURGERY, Issue 1 2003Suhattaya Angsuwarangsee MD Background. Melasma is common and can cause major psychological impact. To date, the mainstay of treatment, including various hypopigmenting agents and chemical peels, is ineffective and can cause adverse effects. Laser is a new approach and is yet to be explored for its efficacy and safety. Objective. To compare combined Ultrapulse CO2 laser and Q-switched alexandrite laser (QSAL) with QSAL alone in the treatment of refractory melasma. Methods. Six Thai females were treated with combined Ultrapulse CO2 laser and QSAL on one side of the face and QSAL alone on the other side. The outcome was evaluated periodically for up to 6 months using the modified Melasma Area and Severity Index score and the modified Melasma Area and Melanin Index score. Results. The side with combination treatment had a statistically significant reduction of both scores. On the QSAL side, the score reduction was not significant. Two cases developed severe postinflammatory hyperpigmentation and were effectively treated with bleaching agents. Transient hypopigmentation and contact dermatitis were observed with the combination treatment side. Conclusions. Combined Ultrapulse CO2 laser and QSAL showed a better result than QSAL alone but was associated with more frequent adverse effects. Long-term follow-up and a larger number of cases are required to determine its efficacy and safety for refractory melasma. [source] Visual search in typically developing toddlers and toddlers with Fragile X or Williams syndromeDEVELOPMENTAL SCIENCE, Issue 1 2004Gaia Scerif Visual selective attention is the ability to attend to relevant visual information and ignore irrelevant stimuli. Little is known about its typical and atypical development in early childhood. Experiment 1 investigates typically developing toddlers' visual search for multiple targets on a touch-screen. Time to hit a target, distance between successively touched items, accuracy and error types revealed changes in 2- and 3-year-olds' vulnerability to manipulations of the search display. Experiment 2 examined search performance by toddlers with Fragile X syndrome (FXS) or Williams syndrome (WS). Both of these groups produced equivalent mean time and distance per touch as typically developing toddlers matched by chronological or mental age; but both produced a larger number of errors. Toddlers with WS confused distractors with targets more than the other groups; while toddlers with FXS perseverated on previously found targets. These findings provide information on how visual search typically develops in toddlers, and reveal distinct search deficits for atypically developing toddlers. [source] Size-related deterioration of semi-natural grassland fragments in SwedenDIVERSITY AND DISTRIBUTIONS, Issue 1 2002Katariina Kiviniemi Abstract. One of the most dramatic landscape changes during the 20th century in Sweden, like in most of Europe, has been the reduction and fragmentation of semi-natural grasslands. Using a set of remnant semi-natural grasslands, chosen to be as similar as possible, but differing in size, we have examined whether size of remnant fragments of traditionally managed semi-natural grasslands in Sweden is related to patterns of species richness and composition. We focused on edge-to-interior relationships, since we expected that a possible impact from invasive habitat generalists would be manifested in a gradient from the edge of fragments to their interior. We found no relationship between size of grassland fragments and (a) overall species richness, (b) species richness at different spatial scales, and (c) abundance of some typical invader species or species characteristic of semi-natural grasslands. However, the results indicated that larger grasslands have a comparatively larger number of species in the edges, whereas the opposite pattern was found in smaller grasslands. The similarity in species composition between the edge and the interior of the pastures also increased with grassland size. Thus, even though the overall species richness is still unaffected by reduction in grassland fragment size, the edges of smaller grasslands show signs of degradation, i.e. reduction in species richness and a decreased similarity to the grassland interior. We suggest that these kinds of effects may be early signs of fragmentation effects that in the future will result in species loss even if the present distribution of semi-natural grasslands is maintained. [source] Injecting risk behaviour and related harm among men who use performance- and image-enhancing drugsDRUG AND ALCOHOL REVIEW, Issue 6 2008BRIONY LARANCE Abstract Introduction and Aims. Performance- and image-enhancing drugs have the potential to be a significant public health issue. Detailed data on PIEDs injection are difficult to obtain because of the illicit and unsupervised way in which many PIEDs are used, and the hidden nature of the group. Our study examines the patterns of use, risk behaviours and related harm associated with PIEDs injection. We also report the ways in which PIEDs users currently seek injecting equipment and harm-reduction advice. Design and Method. Data were obtained via a structured questionnaire administered in face-to-face interviews with 60 men who used PIEDs (primarily anabolic androgenic steroids) for non-medical purposes. Results. Although the rates of needle sharing were low (5%), the men more frequently reported re-use of needles/equipment, injecting from a shared container (bladders, vials, etc.), injecting other illicit drugs, injecting insulin and targeting small muscle groups. Self-reports of being hepatitis C antibody positive were associated with lifetime use of heroin and injection of other illicit drugs. All HIV positive participants were gay/bisexual men. Participants reported a range of other injection-related injuries and diseases such as fevers, scarring and abscesses. ,Risky' injectors (38% of participants) were more likely to initiate PIEDs use at a younger age, use PIEDs in a larger number of cycles per year and report involvement in a violent/aggressive incident than ,low risk' injectors and report involvement in a violent/aggressive incident than ,low risk' injectors. Participants mainly reported seeking information about PIEDs from internet sites (62%) and friends (55%). Conclusions. An over-reliance on personal networks and internet forums limits this groups' access to objective harm reduction advice and primary care services. Targeted, PIEDs-specific interventions are needed. [source] Parameter identification of framed structures using an improved finite element model-updating method,Part I: formulation and verificationEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 5 2007Eunjong Yu Abstract In this study, we formulate an improved finite element model-updating method to address the numerical difficulties associated with ill conditioning and rank deficiency. These complications are frequently encountered model-updating problems, and occur when the identification of a larger number of physical parameters is attempted than that warranted by the information content of the experimental data. Based on the standard bounded variables least-squares (BVLS) method, which incorporates the usual upper/lower-bound constraints, the proposed method (henceforth referred to as BVLSrc) is equipped with novel sensitivity-based relative constraints. The relative constraints are automatically constructed using the correlation coefficients between the sensitivity vectors of updating parameters. The veracity and effectiveness of BVLSrc is investigated through the simulated, yet realistic, forced-vibration testing of a simple framed structure using its frequency response function as input data. By comparing the results of BVLSrc with those obtained via (the competing) pure BVLS and regularization methods, we show that BVLSrc and regularization methods yield approximate solutions with similar and sufficiently high accuracy, while pure BVLS method yields physically inadmissible solutions. We further demonstrate that BVLSrc is computationally more efficient, because, unlike regularization methods, it does not require the laborious a priori calculations to determine an optimal penalty parameter, and its results are far less sensitive to the initial estimates of the updating parameters. Copyright © 2006 John Wiley & Sons, Ltd. [source] On the Use of the Moving Average Trading Rule to Test for Weak Form Efficiency in Capital MarketsECONOMIC NOTES, Issue 2 2008Alexandros E. Milionis The examination for the possible existence of predictive power in the moving average trading rule has been used extensively to test the hypothesis of weak form market efficiency in capital markets. This work focuses mainly on the study of the variation of the moving average (MA) trading rule performance as a function of the length of the longer MA. Empirical analysis of daily data from NYSE and the Athens Stock Exchange reveal high variability of the performance of the MA trading rule as a function of the MA length and on some occasions the series of successive trading rule total returns is non-stationary. These findings have direct implications in weak form market efficiency testing. Indeed, given this high variability of the performance of the MA trading rule, by just finding out that trading rules with some specific combinations of MA lengths can or cannot beat the market, as is the case in most of the published work thus far, is not enough evidence for or against the existence of weak form market efficiency. Results also show that on average in about three out of four cases trading rule signals are false, a fact that leaves a lot of space for improved trading rule performance if trading rule signals are combined with other information (e.g. filters, or volume of trade). Finally, some evidence of enhanced trading rule performance for the shorter MA lengths was found. This enhanced performance is partly attributed to the higher probability that a trading rule signal is not a whipsaw, as well as to the larger number of days out-of-the-market which are associated with shorter MA lengths. [source] Proteomic analysis of rat brain tissue: Comparison of protocols for two-dimensional gel electrophoresis analysis based on different solubilizing agentsELECTROPHORESIS, Issue 24 2002Lucia Carboni Abstract The present study reports a comparison of recently described solubilizing methods, to set up a simple protocol for obtaining two-dimensional (2-D) gel electrophoresis maps of brain tissue. Different protocols were used for preparing rat brain homogenates and the resulting maps were compared by image analysis. Three different detergents, two delipidation methods, and introduction of a fractionation step based on different protein solubility in surfactants, were evaluated. When using efficient zwitterionic detergents (3-[(3-cholamidopropyl)dimethylamino]-1-propanesulfonate, CHAPS; amidosulfobetaine 14, ASB-14), the patterns obtained by direct loading of total extracts were qualitatively overlapping with patterns obtained from fractionated samples. In contrast, a weaker nonionic agent (Nonidet P-40, NP-40) produced a different protein pattern in the collected fractions. Delipidation did not improve the results for all the different extraction methods. Immunoblots performed with antibodies recognizing cytosolic and membrane-spanning proteins, which were detected as nondegraded spots, showed that membrane proteins with intermediate molecular mass could be recovered. We suggest, as a simple and efficient method for preparing rat brain maps, the homogenization in a solution containing an efficient zwitterionic surfactant, which allows to solubilize cytosolic and membrane proteins in a single step. Alternatively, a fractionation can be carried out on samples homogenized by a weak solubilizing agent, a more labor-intensive effort resulting in a larger number of proteins on two maps. [source] Correlates of Board Empowerment in Small CompaniesENTREPRENEURSHIP THEORY AND PRACTICE, Issue 5 2007Jonas Gabrielsson This study seeks to advance the understanding of board empowerment in small companies. Predictions based on agency and resource dependency theories were used to examine how contingency factors correlate with board empowerment, in this study conceptualized as a larger number of board members, a higher representation of outside directors, and separate CEO and board chair positions. Statistical analyses on a sample of 135 small companies gave ample support for the agency-theoretic prediction that board empowerment in small companies is a response to satisfy the demands from owners not directly involved in managing the company. Other factors influencing board empowerment were younger CEOs, high degree of exports, and past poor company performance. The influence of these contingency factors, however, was not as strong and extensive as the presence of outside owners. The article ends with a discussion of the findings and their implications for understanding boards and governance in small companies. [source] Single layer centrifugation of stallion spermatozoa consistently selects the most robust spermatozoa from the rest of the ejaculate in a large sample sizeEQUINE VETERINARY JOURNAL, Issue 7 2010J. M. MORRELL Summary Reasons for performing study: An improvement in sperm quality after single layer centrifugation (SLC) has been seen in previous studies using small sample sizes (for example, n = 10 stallions). There is a need to investigate whether this improvement is repeatable over several breeding seasons with a larger number of stallions (n , 30 stallions). Objective: To make a retrospective analysis of the results of SLC performed on more than 250 sperm samples (176 ejaculates) from 31 stallions in 3 consecutive breeding seasons. Methods: Sperm quality (motility, proportion of morphologically normal spermatozoa and the proportion of spermatozoa with undamaged chromatin) was assessed before and after SLC. Results: All parameters of sperm quality examined were significantly better in sperm samples after SLC than in their unselected counterparts (P<0.001 for each parameter). The yield of spermatozoa obtained after SLC was influenced by the type of extender used and also by the concentration of spermatozoa in the original ejaculate, with fewer spermatozoa being recovered when the loading dose contained a high concentration of spermatozoa. The optimal concentration was approximately 100 × 106/ml. Sperm concentration in the samples loaded on to the colloid influenced the sperm yield while the type of semen extender affected sperm quality and survival. Furthermore, the scaled-up SLC method was found to be suitable for use with a range of ejaculates, with similar sperm kinematics being observed for standard and scaled-up preparations. Conclusions: SLC consistently improved the quality of stallion sperm samples from a large number of ejaculates. The method could be scaled-up, allowing larger volumes of ejaculate to be processed easily from a wide range of stallions. [source] Osseous abnormalities associated with collateral desmopathy of the distal interphalangeal joint.EQUINE VETERINARY JOURNAL, Issue 8 2009Part 2: Treatment, outcome Summary Reasons for performing study: There are currently few long-term follow-up data relating to recovery from injury of a collateral ligament (CL) of the distal interphalangeal (DIP) joint and limited information about the effect of associated osseous injury on prognosis. Objectives: To describe long-term follow-up results for horses with CL injury, with and without associated osseous injury; and to determine the effect of extracorporeal shock wave therapy (ECSWT) or radial pressure wave therapy (RPWT) on outcome. Hypotheses: Prognosis for return to performance for horses with CL-related osseous injury would be worse than for horses with CL injury alone. Methods: Magnetic resonance images from 313 feet of 289 horses with foot pain and a definitive diagnosis of collateral desmopathy of the DIP joint were analysed retrospectively for presence of osseous abnormality associated with the ligament origin or insertion and the middle and distal phalanges. Horses were assigned to groups according to the combination of their injuries. Type of treatment was recorded and follow-up information obtained. Thirty-two horses with additional sources of lameness were excluded from analysis of outcome. Results: Follow-up data were available for 182 horses, 55 of which had follow-up information for up to 2 years after presentation. Twenty-seven percent of horses with CL injury alone and 34% of horses with CL related osseous injury returned to their previous performance level. Prognosis for a combination of injuries to multiple soft tissue and osseous structures within the hoof capsule was substantially worse. There was no effect of ECSWT or RPWT on outcome. Conclusions: The presence of mild to moderate CL related osseous injury does not appear to influence prognosis compared with CL injury alone. Clinical relevance: Further studies of a larger number of horses are necessary in order to ascertain if specific types of osseous pathology influence return to performance levels. [source] Do European Primarily Internet Banks Show Scale and Experience Efficiencies?EUROPEAN FINANCIAL MANAGEMENT, Issue 4 2007Javier Delgado G21; O32; O33 Abstract Empirical evidence shows that Internet banks worldwide have underperformed newly chartered traditional banks mainly because of their higher overhead costs. European banks have not been an exception in this regard. This paper analyses, for the first time in Europe, whether this is a temporary phenomenon and whether Internet banks may generate scale economies in excess of those available to traditional banks. Also do they (and their customers) accumulate experience with this new business model, allowing them to perform as well or even better than their peers, the traditional banks? To this end, we have generally followed the same analytical framework and methodology used byDeYoung (2001, 2002, 2005)for Internet banks in the USA although the limitations in the availability of data, as well as the existence of different regulatory frameworks and market conditions, particularly in the retail segment, in the 15 European Union countries have required some modifications to the methodology. The empirical analysis confirms that, as is the case for US banks, European Internet banks show technologically based scale economies, while no conclusive evidence exists of technology based learning economies. As Internet banks get larger, the profitability gap with traditional banks shrinks. To the extent that Internet banks are profitable, European authorities may encourage a larger number of consumers to use this delivery channel, by tackling consumers security concerns. This would allow Internet banks to capture more of the potential scale efficiencies implied in our estimations. [source] Clinical features of non-hypertensive lobar intracerebral hemorrhage related to cerebral amyloid angiopathyEUROPEAN JOURNAL OF NEUROLOGY, Issue 6 2010M. Hirohata Background and purpose: The present study aims to clarify the clinical features of non-hypertensive cerebral amyloid angiopathy-related lobar intracerebral hemorrhage (CAA-L-ICH). Methods: We investigated clinical, laboratory, and neuroimaging findings in 41 patients (30, women; 11, men) with pathologically supported CAA-L-ICH from 303 non-hypertensive Japanese patients aged ,55, identified via a nationwide survey as symptomatic CAA-L-ICH. Results: The mean age of patients at onset of CAA-L-ICH was 73.2 ± 7.4 years; the number of patients increased with age. The corrected female-to-male ratio for the population was 2.2, with significant female predominance. At onset, 7.3% of patients received anti-platelet therapy. In brain imaging studies, the actual frequency of CAA-L-ICHs was higher in the frontal and parietal lobes; however, after correcting for the estimated cortical volume, the parietal lobe was found to be the most frequently affected. CAA-L-ICH recurred in 31.7% of patients during the average 35.3-month follow-up period. The mean interval between intracerebral hemorrhages (ICHs) was 11.3 months. The case fatality rate was 12.2% at 1 month and 19.5% at 12 months after initial ICH. In 97.1% of patients, neurosurgical procedures were performed without uncontrollable intraoperative or post-operative hemorrhage. Conclusions: Our study revealed the clinical features of non-hypertensive CAA-L-ICH, including its parietal predilection, which will require further study with a larger number of patients with different ethnic backgrounds. [source] Evaluating cluster analysis solutions: an application to the Italian NEO personality inventoryEUROPEAN JOURNAL OF PERSONALITY, Issue S1 2002Claudio Barbaranelli This paper is concerned with the evaluation of cluster analysis solutions. Internal criteria and replication issues are compared and applied to empirical data collected from an Italian sample of 421 young adults, using the NEO Personality Inventory. The following internal criteria were considered: C, gamma, and G(,+,) indices, and point-biserial correlation. Replication was examined (i) ,internally' using double cross-validation and bootstrap approaches and (ii) ,externally' by comparing the solution obtained on the Italian sample with the results obtained in German and Spanish samples. While replication analyses supported three- and four-cluster solutions, internal criteria (with the exception of point-biserial correlation) tended to privilege solutions with a much larger number of groups. Advantages and limitations of the different strategies are discussed. Copyright © 2002 John Wiley & Sons, Ltd. [source] Prevalence and diversity of insertion sequences in the genome of Bacillus thuringiensis YBT-1520 and comparison with other Bacillus cereus group membersFEMS MICROBIOLOGY LETTERS, Issue 1 2010Ning Qiu Abstract Members of the Bacillus cereus group are closely related bacteria that exhibit highly divergent pathogenic properties. Sequencing of Bacillus thuringiensis ssp. kurstaki strain YBT-1520 revealed an increased number of insertion sequences (ISs) compared with those of the published B. cereus group genomes. Although some of these ISs have been observed and summarized in B. thuringiensis previously, a genomic characterization of their content is required to reveal their distribution and evolution. The result shows that the larger number of transposase coding genes on YBT-1520 chromosome is mainly caused by the amplification of IS231C, IS232A and ISBth166. Some functional genes have been disrupted through the insertion of ISs, preferentially IS231C. By comparing the Southern hybridization profiles of different B. thuringiensis strains, the existence of ISBth166 was mainly found in serovar kurstaki and the recent expansion of IS231C between different kurstaki isolates was suggested. In addition to revealing the ISs profile in YBT-1520 as well as the comparison in the B. cereus group, this study will contribute to further comparative analyses of multiple B. thuringiensis strains aimed at understanding the IS-mediated genomic rearrangements among them. [source] Using patch studies to link mesoscale patterns of feeding and growth in larval fish to environmental variabilityFISHERIES OCEANOGRAPHY, Issue 4 2002John F. Dower We present results from a series of three patch studies designed to examine links between environmental variability and mesoscale patterns of feeding and growth of larval radiated shanny (Ulvaria subbifurcata). We examine the effects of variability in temperature, turbulence and prey concentration on both the mean (i.e. population level) and the variance (i.e. individual level) of larval feeding and growth rates among the three bays. Although both gut fullness and growth rates differ significantly between bays, our results show only weak environmental influences. When larvae are pooled across bays (i.e. treated as independent observations), environmental factors generally explain <4% of the variability in gut fullness. When treated as daily mean residuals, however, temperature accounts for 41% of the variability in mean gut fullness, while both temperature and prey concentration also explain significant portions of the variance in gut fullness (38 and 43%, respectively). Between-bay differences in larval growth rates are consistent with patterns of temperature variation but not with patterns of prey availability. Studies relying on tracking a single patch of larvae typically suffer from having too few observations to detect significant relationships between feeding or growth and environmental variables. By following three patches we collected a larger number of observations. However, as we encountered only a limited range of environmental conditions it remains difficult to adequately assess the role of environmental factors. In part, this problem stems from the inability of fisheries oceanographers to track the recent environmental history of individual larvae on the same fine scales currently employed to collect biological data (e.g. guts and otoliths) on individuals. [source] Lability of organic carbon in lakes of different trophic statusFRESHWATER BIOLOGY, Issue 6 2009A. P. OSTAPENIA Summary 1. We used first-order kinetic parameters of biological oxygen demand (BOD), the constant of aerobic decomposition (k) and the asymptotic value of BOD (BODult), to characterise the lability of organic carbon pools in six lakes of different trophic state: L. Naroch, L. Miastro and L. Batorino (Belarus), L. Kinneret (Israel), L. Ladoga (Russia) and L. Mendota (U.S.A.). The relative contributions of labile and refractory organic carbon fractions to the pool of total organic carbon (TOC) in these lakes were quantified. We also determined the amounts of labile organic carbon within the dissolved and particulate TOC pools in the three Belarus lakes. 2. Mean annual chlorophyll concentrations (used as a proxy for lake trophic state) ranged from 2.3 to 50.6 ,g L,1, labile organic carbon (OCL = 0.3BODult) from 0.75 to 2.95 mg C L,1 and k from 0.044 to 0.14 day,1. 3. Our data showed that there were greater concentrations of OCL but lower k values in more productive lakes. 4. In all cases, the DOC fraction dominated the TOC pool. OCL was a minor component of the TOC pool averaging about 20%, irrespective of lake trophic state. 5. In all the lakes, most (c. 85%) of the DOC pool was refractory, corresponding with published data based on measurements of bacterial production and DOC depletion. In contrast, a larger fraction (27,55%) of the particulate organic carbon (POC) pool was labile. The relative amount of POC in the TOC pool tended to increase with increasing lake productivity. 6. Long-term BOD incubations can be valuable in quantifying the rates of breakdown of the combined particulate and dissolved organic carbon pools and in characterising the relative proportions of the labile and recalcitrant fractions of these pools. If verified from a larger number of lakes our results could have important general implications. [source] Energy Group optimization for forward and inverse problems in nuclear engineering: application to downwell-logging problemsGEOPHYSICAL PROSPECTING, Issue 2 2006Elsa Aristodemou ABSTRACT Simulating radiation transport of neutral particles (neutrons and ,-ray photons) within subsurface formations has been an area of research in the nuclear well-logging community since the 1960s, with many researchers exploiting existing computational tools already available within the nuclear reactor community. Deterministic codes became a popular tool, with the radiation transport equation being solved using a discretization of phase-space of the problem (energy, angle, space and time). The energy discretization in such codes is based on the multigroup approximation, or equivalently the discrete finite-difference energy approximation. One of the uncertainties, therefore, of simulating radiation transport problems, has become the multigroup energy structure. The nuclear reactor community has tackled the problem by optimizing existing nuclear cross-sectional libraries using a variety of group-collapsing codes, whilst the nuclear well-logging community has relied, until now, on libraries used in the nuclear reactor community. However, although the utilization of such libraries has been extremely useful in the past, it has also become clear that a larger number of energy groups were available than was necessary for the well-logging problems. It was obvious, therefore, that a multigroup energy structure specific to the needs of the nuclear well-logging community needed to be established. This would have the benefit of reducing computational time (the ultimate aim of this work) for both the stochastic and deterministic calculations since computational time increases with the number of energy groups. We, therefore, present in this study two methodologies that enable the optimization of any multigroup neutron,, energy structure. Although we test our theoretical approaches on nuclear well-logging synthetic data, the methodologies can be applied to other radiation transport problems that use the multigroup energy approximation. The first approach considers the effect of collapsing the neutron groups by solving the forward transport problem directly using the deterministic code EVENT, and obtaining neutron and ,-ray fluxes deterministically for the different group-collapsing options. The best collapsing option is chosen as the one which minimizes the effect on the ,-ray spectrum. During this methodology, parallel processing is implemented to reduce computational times. The second approach uses the uncollapsed output from neural network simulations in order to estimate the new, collapsed fluxes for the different collapsing cases. Subsequently, an inversion technique is used which calculates the properties of the subsurface, based on the collapsed fluxes. The best collapsing option is chosen as the one that predicts the subsurface properties with a minimal error. The fundamental difference between the two methodologies relates to their effect on the generated ,-rays. The first methodology takes the generation of ,-rays fully into account by solving the transport equation directly. The second methodology assumes that the reduction of the neutron groups has no effect on the ,-ray fluxes. It does, however, utilize an inversion scheme to predict the subsurface properties reliably, and it looks at the effect of collapsing the neutron groups on these predictions. Although the second procedure is favoured because of (a) the speed with which a solution can be obtained and (b) the application of an inversion scheme, its results need to be validated against a physically more stringent methodology. A comparison of the two methodologies is therefore given. [source] The value of early treatment in patients with haemophilia and inhibitorsHAEMOPHILIA, Issue 3 2010K. KAVAKLI Summary., Development of inhibitors to infused factor concentrates represents a major clinical and economic challenge in the treatment of haemophilic patients. It has been shown that a delay in initiation of treatment leads to requirement of a larger number of injections to stop the bleeding but this has never been formally linked to costs associated with the bleeding. The objectives of this study were to assess the relationship between time to initiation of NovoSeven® and total costs, number of doses administered and time to bleeding resolution in mild to moderate bleeding episodes. Data on time to treatment initiation, time to bleeding resolution and on all resource use related to the bleeding were extracted from medical records in Turkey for 129 bleeding episodes. Regression analysis was used to assess the impact of time to treatment on outcomes. Longer time to treatment initiation increased both total costs associated with the bleeding, the number of doses needed and the time to bleeding resolution. Treatment in hospital was associated with significantly longer time to treatment, higher costs and longer time to bleeding resolution as compared with home treatment or outpatient treatment. When controlling for other bleeding characteristics, the cost of bleedings treated in hospital was more than 150% higher. This study shows that treatment with NovoSeven® should be initiated as soon as possible after the onset of bleeding in order to minimize costs and optimize outcomes. Home treatment reduces time to treatment initiation and also reduces costs related to the bleeding. [source] Peripheral T-cell lymphoma gene expression profilesHEMATOLOGICAL ONCOLOGY, Issue 3 2006B. Martinez-Delgado Abstract Expression profiling using DNA microarrays has been very helpful to improve our knowledge of the pathobiology of many tumour types, including lymphomas. Peripheral T-cell lymphomas (PTCL) constitute an heterogeneous group of tumours with different morphologic, immunophenotypic, and clinical characteristics. Their complexity and their low frequency in the western countries have made difficult the identification of molecular events responsible of the development of these tumours. The first studies on expression profiling of PTCL have also revealed heterogeneity at this level, mainly regarding the PTCL NOS subgroup. Different molecular subgroups within PTCL unspecified have been identified associated to different expression profiles. However, the clinical significance of this molecular sub-classification remains to be probed in studies involving larger number of samples. In addition, the expression level of NF-kB pathway genes allowed to differentiate two PTCL subgroups, and this difference could have clinical interest. In general, PTCL expression profiles are difficult to interpret due to the significant proportion of other infiltrating cells accompanying the tumour. However, microarrays are being a helpful tool in the initial task of dissecting the PTCL expression profile. Copyright © 2006 John Wiley & Sons, Ltd. [source] Double-dose double-phase use of second generation hepatitis B virus vaccine in patients after living donor liver transplantation: Not an effective measure in transplant recipientsHEPATOLOGY RESEARCH, Issue 1 2009Noriyo Yamashiki Aims:, Post-transplant active immunization for chronic hepatitis B patients has been attempted in several studies with controversial results. We assessed the effect of a double-dose double-phase vaccination regimen among partial living donor liver recipients. Methods:, Eighteen patients who underwent liver transplantation (LT) for chronic hepatitis B and two non-hepatitis B virus (HBV)-infected patients who received hepatitis B core antibody (HBcAb)-positive donor organs were recruited 18,78 months after LT. All were on hepatitis B immunoglobulin (HBIG) mono-prophylaxis before and throughout vaccination, to maintain hepatitis B surface antibody (HBsAb) titers of more than 100 IU/mL. Recombinant hepatitis B surface antigen vaccine (40 µg) was administered intramuscularly during weeks 0, 4, 8, 24, 28 and 32. Results:, The patients consisted of 15 males and five females with a median age of 52 (39,59) years. None developed a sufficient HBsAb titer above 500 IU/mL by week 48. In two patients whose maximum HBsAb titer increased to above 300 IU/mL, we attempted to skip HBIG, but shortly thereafter the titer dropped below 100 IU/mL and HBIG administration was resumed. Although the HBIG dose was reduced during and after vaccination, cessation of administration was not achieved. Conclusion:, Double-dose double-phase use of second generation recombinant vaccine was not effective in this study population. The selected population should be targeted for a conventional vaccine regimen, and different approaches, such as strong adjuvant or pre-S containing protein, should be further tested in a larger number of patients after LT for chronic hepatitis B. [source] Synthesis of ,-fluoro-,-trifluoromethyl alka-2,4-dienesHETEROATOM CHEMISTRY, Issue 3 2007Yanchang Shen The palladium/copper(I) iodide cocatalyzed coupling reaction of (Z)-,-fluoro-,-trifluoromethylstannanes (1) with vinyl iodides (2) has been explored giving substituted ,-fluoro-,-trifluoromethyl dienes (3) in 33,95% yields. In studies we have conducted so far, a larger number of the configurations of the products remained unchanged (cases 3a, 3e,h), though in several cases (cases 3b,d) two configurations of the products were obtained. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:208,211, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20284 [source] The effect of parent sex on prey deliveries to fledgling Eurasian Sparrowhawks Accipiter nisusIBIS, Issue 4 2003Katrine Eldegard The relative contribution of each parent when providing for the fledglings has been recorded in only a few raptor species. We studied prey deliveries by Eurasian Sparrowhawk Accipiter nisus parents to fledglings at seven nests in southern Norway. Parents and young were fitted with radio-transmitters. Males delivered a larger number of prey to the young than did females throughout the post-fledging period (on average c. 80% of the deliveries). Two females were never observed to deliver food to the offspring, and their mates apparently raised the young to independence alone. The duration of the post-fledging period was positively related to per-capita delivery rate in the late stage. [source] Implicit integration of a mixed isotropic,kinematic hardening plasticity model for structured claysINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 10 2008Angelo Amorosi Abstract In recent years, a number of constitutive models have been proposed to describe mathematically the mechanical response of natural clays. Some of these models are characterized by complex formulations, often leading to non-trivial problems in their numerical integration in finite elements codes. The paper describes a fully implicit stress-point algorithm for the numerical integration of a single-surface mixed isotropic,kinematic hardening plasticity model for structured clays. The formulation of the model stems from a compromise between its capability of reproducing the larger number of features characterizing the behaviour of structured clays and the possibility of developing a robust integration algorithm for its implementation in a finite elements code. The model is characterized by an ellipsoid-shaped yield function, inside which a stress-dependent reversible stiffness is accounted for by a non-linear hyperelastic formulation. The isotropic part of the hardening law extends the standard Cam-Clay one to include plastic strain-driven softening due to bond degradation, while the kinematic hardening part controls the evolution of the position of the yield surface in the stress space. The proposed algorithm allows the consistent linearization of the constitutive equations guaranteeing the quadratic rate of asymptotic convergence in the global-level Newton,Raphson iterative procedure. The accuracy and the convergence properties of the proposed algorithm are evaluated with reference to the numerical simulations of single element tests and the analysis of a typical geotechnical boundary value problem. Copyright © 2007 John Wiley & Sons, Ltd. [source] Dynamic crack propagation with cohesive elements: a methodology to address mesh dependencyINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 1 2004F. Zhou Abstract In this paper, two brittle fracture problems are numerically simulated: the failure of a ceramic ring under centrifugal loading and crack branching in a PMMA strip. A three-dimensional finite element package in which cohesive elements are dynamically inserted has been developed. The cohesive elements' strength is chosen to follow a modified weakest link Weibull distribution. The probability of introducing a weak cohesive element is set to increase with the cohesive element size. This reflects the physically based effect according to which larger elements are more likely to contain defects. The calculations illustrate how the area dependence of the Weibull model can be used to effectively address mesh dependency. On the other hand, regular Weibull distributions have failed to reduce mesh dependency for the examples shown in this paper. The ceramic ring calculations revealed that two distinct phenomena appear depending on the magnitude of the Weibull modulus. For low Weibull modulus, the fragmentation of the ring is dominated by heterogeneities. Whereas many cracks were generated, few of them could propagate to the outer surface. Monte Carlo simulations revealed that for highly heterogeneous rings, the number of small fragments was large and that few large fragments were generated. For high Weibull modulus, signifying that the ring is close to being homogeneous, the fragmentation process was very different. Monte Carlo simulations highlighted that a larger number of large fragments are generated due to crack branching. Copyright © 2003 John Wiley & Sons, Ltd. [source] On the influence of numerical schemes and subgrid,stress models on large eddy simulation of turbulent flow past a square cylinderINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 3 2002A. Nakayama Abstract Influence of finite difference schemes and subgrid-stress models on the large eddy simulation calculation of turbulent flow around a bluff body of square cylinder at a laboratory Reynolds number, has been examined. It is found that the type and the order of accuracy of finite-difference schemes and the subgrid-stress model for satisfactory results are dependent on each other, and the grid resolution and the Reynolds number. Using computational grids manageable by workstation-level computers, with which the near-wall region of the separating boundary layer cannot be resolved, central-difference schemes of realistic orders of accuracy, either fully conservative or non-conservative, suffer stability problems. The upwind-biased schemes of third order and the Smagorinsky eddy-viscosity subgrid model can give reasonable results resolving much of the energy-containing turbulent eddies in the boundary layers and in the wake and representing the subgrid stresses in most parts of the flow. Noticeable improvements can be obtained by either using higher order difference schemes, increasing the grid resolution and/or by implementing a dynamic subgrid stress model, but each at a cost of increased computational time. For further improvements, the very small-scale eddies near the upstream corners and in the laminar sublayers need to be resolved but would require a substantially larger number of grid points that are out of the range of easily accessible computers. Copyright © 2002 John Wiley & Sons, Ltd. [source] A preliminary report on the implication of RT,PCR detection of DAZ, RBMY1, USP9Y and Protamine-2 mRNA in testicular biopsy samples from azoospermic menINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 1 2002A. Friel In this study, reverse transcription,polymerase chain reaction (RT,PCR) was optimized to analyse the presence of DAZ, RBMY1, USP9Y, protamine-2, SRY and actin messenger RNA (mRNA) in testicular cells of men suffering from idiopathic azoospermia. All samples (n=28), including five controls, showed normal expression of actin, SRY and USP9Y. Sperm was not recovered from eight patients after testicular biopsy. Of these, four patients showed altered mRNA levels for the fertility genes, DAZ, RBMY1 and protamine-2. One patient, who was previously shown to be azoospermia factor region (AZF)b deleted, lacked RBM mRNA and presented with reduced amplification of protamine-2 mRNA. This correlated with previous studies, which proposed that RBM expression is exclusive to AZFb and that the lack of testicular RBMY1 mRNA results in suppressed spermatogenesis. Two patients were each lacking DAZ mRNA but did show expression of RBMY1 mRNA at a reduced level, suggesting that there might be residual spermatogenesis in the absence of DAZ expression. Protamine-2 mRNA was detected in one patient and was absent in the second patient. Finally, one patient lacked DAZ, RBMY1 and protamine-2 mRNA. The 19 remaining azoospermic patients presented with normal expression patterns for each of the fertility genes studied. This study demonstrates that the expression of spermatogenesis-specific genes varies in azoospermia. The study of the expression of such genes in a larger number of patients might be useful in characterizing and identifying subpopulations of azoospermic men. [source] Strong expression of IGF1R in pediatric gastrointestinal stromal tumors without IGF1R genomic amplification,INTERNATIONAL JOURNAL OF CANCER, Issue 11 2010Katherine A. Janeway Abstract Wildtype (WT) gastrointestinal stromal tumors (GISTs), lacking mutations in KIT or PDGFRA, represent 85% of GISTs in pediatric patients. Treatment options for pediatric WT GIST are limited. Recently, expression profiling of a limited number of pediatric and adult WT GISTs and more in depth study of a single pediatric WT GIST implicated the insulin-like growth factor 1 receptor (IGF1R) as a potential therapeutic target in pediatric WT GIST. We performed immunoblotting, SNP and FISH studies to determine the extent of expression, biochemical activation and genomic amplification of IGF1R in a larger number of pediatric WT GISTs. Pediatric WT GISTs expressed IGF1R strongly, whereas typical adult KIT mutant GISTs did not. IGF1R gene amplification was not detected in pediatric WT GISTs, and some KIT -mutant GISTs had IGF1R gene deletion due to monosomy 15. Despite the absence of apparent genomic activation mechanisms accounting for overexpression, clinical study of IGF1R-directed therapies in pediatric WT GIST is warranted. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||