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Selected AbstractsFlow Velocity Effect on Leaf Litter Breakdown in Tufa Depositing System (Plitvice Lakes, Croatia)INTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 4 2009Anita Belan Abstract Considerable amount of riparian leaf litter is annually supplied to the cascade Plitvice Lakes and trapped on tufa barriers where it decays together with aquatic macrophytes. These barriers are the sites of heavy calcite precipitation that can widely differ in terms of current velocity. We conducted a leafbag experiment at sites differing in flow velocity and tufa deposition rate. Decomposition of Petasites spp. and Fagus sylvatica was higher under high current (0.80 m/s) and high tufa deposition areas than in low current (< 0.20 m/s) and low tufa deposition areas (k = 0.085 vs. 0.021 for Petasites spp. and 0.009 vs. 0.002 for Fagus sylvatica). We concluded that although tufa deposition could interfere with decomposition by obstructing physical abrasion and also restricting microbial conditioning, thin calcite crusts developed on the surface of the leaves made them more fragile and thus accelerated their decomposition. High current velocity probably magnified this effect by supporting higher tufa deposition and coarser type of tufa fabrics. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Respiratory carbon loss of calcareous grasslands in winter shows no effects of 4 years' CO2 enrichmentFUNCTIONAL ECOLOGY, Issue 2 2002M. Volk Summary 1CO2 exchange measurements in long-term CO2 -enrichment experiments suggest large net carbon gains by ecosystems during the growing season that are not accounted for by above-ground plant biomass. Considerable amounts of C might therefore be allocated below ground. 2Winter ecosystem respiration from temperate grasslands under elevated CO2 may account for the loss of a significant part of the extra C gained during the growing season. To test this hypothesis, dark respiration was assessed throughout the winter of the fourth year of CO2 enrichment in a calcareous grassland. 3Using these data, a model was parameterized to estimate whole-winter respiratory CO2 losses. From November to February, 154 9 g C m,2 were respired under elevated CO2 and 144 5 g C m,2 under ambient [CO2], with no significant difference between the CO2 treatments. 4We conclude that (i) wintertime respiration does not constitute a larger C loss from the ecosystem at elevated CO2; and (ii) the absence of respiratory responses implies no extra growing-season C inputs with month-to-year turnover times at elevated CO2. [source] Organic fertilizers derived from plant materials Part II: Turnover in field trialsJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 2 2006Torsten Müller Abstract Our aim was to investigate two different organic fertilizers derived from plant materials (OFDP) with respect to their nitrogen (N) and carbon (C) turnover in field trials planted with small radish (Raphanus sativus L. var. sativus) and white cabbage (Brassica oleracea L. convar. capitata var. alba) or fallow. The two fertilizers investigated were coarse seed meal of yellow lupin (Lupinus luteus L.) and coarse meal of castor cake (Ricinus communis L.). Under cool spring conditions, the soil turnover of yellow lupin,seed meal was slightly enhanced compared to castor-cake meal. During the vegetation period of the vegetables, N added with both fertilizers was metabolized more or less completely by soil microorganisms. Due to similar efficiencies of the fertilizers tested, no significant difference could be found in the N uptake of plants. From this point of view, yellow lupin,seed meal, which can be produced by farmers themselves, has the potential to replace the widely used castor-cake meal. Considerable amounts of N may remain in the field after fertilization with OFDPs either as mineral N or as easily mineralizable organic N. This N should be utilized immediately by a succeeding crop to avoid leaching losses. [source] Soil N transformations after application of 15N-labeled biomass in incubation experiments with repeated soil drying and rewettingJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 2 2004Hans-Werner Olfs Abstract The effects of repeated soil drying and rewetting on microbial biomass N (Nbio) and mineral N (Nmin) were measured in incubation experiments simulating typical moisture and temperature conditions for soils from temperate climates in the post-harvest period. After application of in vitro15N-labeled fungal biomass to a silty loam, one set of soils was exposed to two drying-rewetting cycles (treatment DR; 14 days to decrease soil moisture to 20,% water-holding capacity (WHC) and subsequently 7 days at 60,% WHC). A control set (treatment CM) was kept at constant moisture conditions (60,% WHC) throughout the incubation. Nbio and Nmin as well as the 15N enrichment of these N pools were measured immediately after addition of 15N-labeled biomass (day 0) and after each change in soil moisture (day 14, 21, 35, 42). Drying and rewetting (DR) resulted in higher Nmin levels compared to CM towards the end of the incubation. Considerable amounts of Nbio were susceptible to mineralization as a result of soil drying (i.e., drying enhanced the turnover of Nbio), and significantly lower Nbio values were found for DR at the end of each drying period. Immediately after biomass incorporation into the soil (day 0), 22,% of the applied 15N was found in the Nmin pool. Some of this 15Nmin must have been derived from dead cells of the applied microbial biomass as only about 80,% of the microbes in the biomass suspension were viable, and only 52,% of the 15Nbio was extractable (using the fumigation-extraction method). The increase in 15Nmin was higher than for unlabeled Nmin, indicating that added labeled biomass was mineralized with a higher rate than native biomass during the first drying period. Overall, the effect of drying and rewetting on soil N turnover was more pronounced for treatment DR compared to CM during the second drying-rewetting cycle, resulting in a higher flush of mineralization and lower microbial biomass N levels. Stickstoffumsatz im Boden nach Applikation 15N-markierter Biomasse in Inkubationsversuchen mit wiederholten Trocknungs-Wiederbefeuchtungszyklen Der Einfluss wiederholter Bodentrocknung und -wiederbefeuchtung auf mikrobiellen Biomasse-N (Nbio) und mineralischen N (Nmin) wurde in Inkubationsversuchen untersucht. Bodenfeuchte und -temperatur wurden entsprechend den typischen Bedingungen in der Nachernte-Periode gemäßigter Klimazonen simuliert. Nach Applikation von in-vitro15N-markierter Biomasse zu einem Krumenboden (schluffiger Lehm) wurde eine Hälfte der Inkubationsgefäße zwei Trocknungs-Wiederbefeuchtungs-Zyklen ausgesetzt (Behandlung DR, d. h., innerhalb von 14 Tagen Absenkung der Bodenfeuchte auf 20,% der Wasserhaltekapazität (WHC) und danach 7 Tage bei 60,% WHC). Die Vergleichsgefäße wurden konstant bei 60,% der WHC inkubiert (Behandlung CM). Nbio und Nmin sowie die 15N-Anreicherung dieser N-Pools wurden sofort nach der Applikation der 15N-markierten Biomasse (Tag 0) und nach jeder Änderung in der Bodenfeuchte (Tag 14, 21, 35, 42) gemessen. Trocknung und Wiederbefeuchtung (DR) resultierte in höheren Nmin -Gehalten im Vergleich zu CM gegen Ende der Inkubation. Bei Bodentrocknung unterlagen höhere Biomasse-Anteile der Mineralisation (d. h., Trocknung forcierte den Umsatz von Nbio), so dass jeweils am Ende der Trocknungsperiode in DR niedrigere Nbio -Gehalte gefunden wurden. Sofort nach der Einarbeitung der Biomasse in den Boden (Tag 0) wurde 22,% des applizierten 15N im Nmin -Pool gefunden. Ein Teil dieses 15Nmin dürfte von bereits toten Zellen der eingesetzten Mikroben-Biomasse stammen, da nur ca. 80,% der Mikroorganismen in der verwendeten Biomasse-Suspension als lebend eingestuft werden konnte und nur 52,% des 15Nbio mittels Fumigations-Extraktions-Methode extrahierbar war. Aus dem deutlicheren Anstieg im 15Nmin im Vergleich zum unmarkierten Nmin kann geschlossen werden, dass während der ersten Trocknungsperiode zugesetzte markierte Biomasse mit einer höheren Rate als bodenbürtige Biomasse mineralisiert wurde. Insgesamt war der Effekt des Trocknens und der Wiederbefeuchtung auf den N-Umsatz im Boden für die Behandlung DR im Vergleich zu CM im zweiten Zyklus ausgeprägter. Dies zeigt sich in einem höheren Mineralisationsschub und in einem niedrigeren Gehalt an Biomasse zum Ende der Inkubation. [source] Comparison of structure development in injection molding of isotactic and syndiotactic polypropylenesPOLYMER ENGINEERING & SCIENCE, Issue 8 2002Dongman Choi A comparative study of the crystallization and orientation development in injection molding isotactic and syndiotactic polypropylenes was made. The injection molded samples were characterized using wide angle X-ray diffraction (WAXD) techniques and birefringence. The injection molded isotactic polypropylene samples formed well-defined sublayers (skin, shear and core zones) and exhibited polymorphic crystal structures of the monoclinic ,-form and the hexagonal ,-form. Considerable amounts of ,-form crystal were formed in the shear and core zones, depending on the injection pressure or on the packing pressure. The isotactic polypropylene samples had relatively high frozen-in orientations in the skin layer and the shear zone. The injection molded syndiotactic polypropylene exhibited the disordered Form I structure, but it did not appear to crystallize during the mold-filling stage because of its slow crystallization rate and to develop a distinct shear zone. The core zone orientation was greatly increased by application of high packing pressure. The isotactic polypropylene samples exhibited much higher birefringence than the syndiotactic polypropylene samples at the skin and shear layers, whereas both materials exhibited similar levels of crystalline orientation in these layers. [source] Transfer of toxaphene and chlordane into farmed rainbow trout, Oncorhynchus mykiss (Walbaum) via feedAQUACULTURE RESEARCH, Issue 12 2002H Karl Abstract The study was carried out to quantitate the transfer of toxaphene and chlordane compounds from commercial fish feed into the edible part of rainbow trout, Oncorhynchus mykiss (Walbaum) under normal rearing conditions. Trout were fed with unspiked high energy feed for salmon (fat content 26,30%) over a period of 19 months. The average weight of trout increased from 10 g to more than 2092 g, reaching sizes of 51 cm length. Considerable amounts of toxaphene and chlordane residues were transferred from fish feed into trout muscle. Toxaphene concentrations increased up to 8.6 µg (, toxaphene indicator compounds 1,3) kg,1 wet weight (w.w.) and chlordane reached 5.3 µg ,oxy -, trans -, cis -chlordane + t -nonachlor kg,1 w.w. Results are also discussed on the contaminant levels based on the fat content and the effect of sexual maturation is considered in this study. The data allow the establishment of transfer rates for toxaphene and chlordane congeners from high energy diet into the edible part of farmed rainbow trout. [source] Checkpointing BSP parallel applications on the InteGrade Grid middlewareCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 6 2006Raphael Y. de Camargo Abstract InteGrade is a Grid middleware infrastructure that enables the use of idle computing power from user workstations. One of its goals is to support the execution of long-running parallel applications that present a considerable amount of communication among application nodes. However, in an environment composed of shared user workstations spread across many different LANs, machines may fail, become inaccessible, or may switch from idle to busy very rapidly, compromising the execution of the parallel application in some of its nodes. Thus, to provide some mechanism for fault tolerance becomes a major requirement for such a system. In this paper, we describe the support for checkpoint-based rollback recovery of Bulk Synchronous Parallel applications running over the InteGrade middleware. This mechanism consists of periodically saving application state to permit the application to restart its execution from an intermediate execution point in case of failure. A precompiler automatically instruments the source code of a C/C++ application, adding code for saving and recovering application state. A failure detector monitors the application execution. In case of failure, the application is restarted from the last saved global checkpoint. Copyright © 2005 John Wiley & Sons, Ltd. [source] Hydrodynamic and Kinetic Modelling of Dust Free and Dusty Radio-Frequency DischargesCONTRIBUTIONS TO PLASMA PHYSICS, Issue 5-6 2004W. J. Goedheer Abstract In this paper hydrodynamic and kinetic approaches to model low pressure capacitively coupled radio-frequency discharges are discussed. In particular approaches and results for power modulated discharges in a mixture of silane and hydrogen and for discharges containing a considerable amount of dust particles will be presented. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] The determinants and characteristics of voluntary disclosure by Indian banking companiesCORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 5 2007Mohammed Hossain Abstract This study reports the results of an empirical investigation of the extent of voluntary disclosure by 38 listed banking companies in India. It also reports the results of the association between company specific characteristics and voluntary disclosure of the sample companies. The study reveals that Indian banks are disclosing a considerable amount of voluntary information. The findings also indicate that size and assets-in-place are significant and other variables such as age, diversification, board composition, multiple exchange listing and complexity of business are insignificant in explaining the level of disclosure. However, this paper has contributed to the academic literature that financial institutions provide voluntary corporate information including social information as discharging their social responsibility and corporate citizenship. Copyright © 2007 John Wiley & Sons, Ltd and ERP Environment. [source] Meet the New Hybrid DesignersDESIGN MANAGEMENT REVIEW, Issue 2 2010Michael Eckersley Many of them have changed careers, or the focus of their careers, and have arrived at graduate design programs from a background very different from that of traditional designers. They're likely to add a different flavor to the design mix,and bring a considerable amount of business acumen, as well. [source] Are CB1 receptor antagonists nootropic or cognitive impairing agents?DRUG DEVELOPMENT RESEARCH, Issue 8 2009Stephen A. Varvel Abstract For more than a decade, a considerable amount of research has examined the effects of rimonabant (SR 141716) and other CB1 receptor antagonists in both in vivo and in vitro models of learning and memory. In addition to its utility in determining whether the effects of drugs are mediated though a CB1 receptor mechanism of action, these antagonists are useful in providing insight into the physiological function of the endogenous cannabinoid system. Several groups have reported that CB1 receptor antagonists enhance memory duration in a variety of spatial and operant paradigms, but not in all paradigms. Conversely, disruption of CB1 receptor signaling also impairs extinction learning in which the animal actively suppresses a learned response when reinforcement has been withheld. These extinction deficits occur in aversively motivated tasks, such as in fear conditioning or escape behavior in the Morris water maze task, but not in appetitively motivated tasks. Similarly, in electrophysiological models, CB1 receptor antagonists elicit a variety of effects, including enhancement of long-term potentiation (LTP), while disrupting long-term depression (LTD) and interfering with transient forms of plasticity, including depolarization-induced suppression of inhibition (DSI) and depolarization-induced suppression of excitation (DSE). The collective results of the in vivo and in vitro studies employing CB1 receptor antagonists, demonstrate that these receptors play integral roles in different components of cognitive processing. Functionally, pharmacological blockade of CB1 receptors may strengthen memory duration, but interferes with extinction of learned behaviors that are associated with traumatic or aversive memories. Drug Dev Res 70:555,565, 2009. © 2009 Wiley-Liss, Inc. [source] Initial stiffness of reinforced concrete structural walls with irregular openingsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 4 2010Bing Li Abstract Reinforced concrete (RC) structural walls with openings are the primary lateral-load-carrying elements utilized in many structures designed to resist earthquakes. A review of the technical literature shows that there is a considerable amount of uncertainty with regards to the elastic stiffness of these structures when subjected to seismic excitations. Current design practices often employ a stiffness reduction factor to deal with this uncertainty. In an attempt to develop additional information regarding the stiffness of these structures, this paper discusses an approach to determine the initial stiffness of RC structural walls with irregular openings and low aspect ratios. This approach would consider the effect of both flexural and shear deformations. As a part of this study, an analytical approach to determine stiffness was also developed and validated by comparing theoretical and experimental results obtained from six RC shear walls with irregular openings. Simple equations for assessing initial stiffness of RC structural walls with irregular openings are then proposed, based on these parametric case studies. Copyright © 2009 John Wiley & Sons, Ltd. [source] Dialysate concentration and pharmacokinetics of 2F-Ara-A in a patient with acute renal failureEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 6 2005Jan T. Kielstein Abstract:, Fludarabine is frequently used for treatment of B-cell chronic lymphocytic leukemia and in conditioning regimes for hematopoietic cell transplantations. The total body clearance of the principal metabolite 2-fluoro-ara-A (2F-Ara-A) correlates with the creatinine clearance. We report data on total dialysate concentration as well as pharmacokinetics of 2F-Ara-A in a patient with anuric acute renal failure. On three consecutive days the patient received a daily dose of 80 mg (40 mg/m2) fludarabine and underwent three consecutive extended (daily) dialysis (ED) sessions. ED removed a considerable amount of the drug. The average dialysis clearance was 33.85 ml/min which is about 25% of the clearance in patients without renal failure. No toxic side effects of the treatment were observed. This case suggests that fludarabine treatment can be considered in patients requiring dialysis if dose reduction and adequate removal of the drug by hemodialysis is provided. [source] Gene networks controlling early cerebral cortex arealizationEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 4 2006Antonello Mallamaci Abstract Early thalamus-independent steps in the process of cortical arealization take place on the basis of information intrinsic to the cortical primordium, as proposed by Rakic in his classical protomap hypothesis [Rakic, P. (1988)Science, 241, 170,176]. These steps depend on a dense network of molecular interactions, involving genes encoding for diffusible ligands which are released around the borders of the cortical field, and transcription factor genes which are expressed in graded ways throughout this field. In recent years, several labs worldwide have put considerable effort into identifying members of this network and disentangling its topology. In this respect, a considerable amount of knowledge has accumulated and a first, provisional description of the network can be delineated. The aim of this review is to provide an organic synthesis of our current knowledge of molecular genetics of early cortical arealization, i.e. to summarise the mechanisms by which secreted ligands and graded transcription factor genes elaborate positional information and trigger the activation of distinctive area-specific morphogenetic programs. [source] Regioselectivity in the Addition of Grignard Reagents to Bis(2-benzothiazolyl) Ketone: C - vs.EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 29 2010O -Alkylation Using Aryl Grignard Reagents Abstract The reaction between bis(2-benzothiazolyl) ketone (1) and a series of ring-substituted phenyl Grignard reagents gives, in considerable amount, the unexpected O -alkylation product derived from the attack of the Grignard reagent to thecarbonyl oxygen atom, thus extending the range of rarely reported cases in which O -alkylation can occur. The expected classic 1,2-addition product and that derived from O -alkylation have been obtained in a relative molar ratio dependent on the substituent on the phenyl ring. Bis(2-benzothiazolyl) aryl carbinols, the classic 1,2-addition products to the carbonyl group of 1, were obtained in high yield through an alternative synthetic route that permitted the limit imposed by O - vs. C -alkylation competition to be overcome. [source] Linking personality states, current social roles and major life goalsEUROPEAN JOURNAL OF PERSONALITY, Issue 6 2009Wiebke BleidornArticle first published online: 23 JUN 200 Abstract Employing an experience-sampling design, the interplay between personality states, social roles and major life goals was examined as it unfolds in the stream of people's daily lives. Multilevel analyses revealed a considerable amount of both within- and between-person variability in state expressions of personality traits justifying further examination of predictors at both levels of analyses. Roles proved as predictors of current personality states albeit effects differed significantly between individuals. Life goals accounted for between-person differences in average personality states but were not effective in predicting differences in relations between personality states and roles. Altogether, findings testify to the viability of the employed research strategy to analyse the interplay between both dispositional and fluctuating influences on individuals' trait expressions in behaviour. Copyright © 2009 John Wiley & Sons, Ltd. [source] FREQUENCY AND SPATIAL PATTERNING OF CLONAL REPRODUCTION IN LOUISIANA IRIS HYBRID POPULATIONSEVOLUTION, Issue 1 2000John M. Burke Abstract., The plant genera in which natural hybridization is most prevalent tend to be outcrossing perennials with some mechanism for clonal (i.e., asexual) reproduction. Although clonal reproduction in fertile, sexually reproducing hybrid populations could have important evolutionary consequences, little attention has been paid to quantifying this parameter in such populations. In the present study, we examined the frequency and spatial patterning of clonal reproduction in two Louisiana iris hybrid populations. Allozyme analysis of both populations revealed relatively high levels of genotypic diversity. However, a considerable amount of clonality was apparent. Nearly half of all genets (47%) in one population and more than half (61%) in the other had multiple ramets. Furthermore, both populations exhibited relatively high levels of genetic structuring, a pattern that resulted from the aggregation of clonal ramets. The occurrence of clonal reproduction in hybrid populations could not only facilitate introgression through an increase in the number of flowering ramets per genet and/or the survivorship of early generation hybrids, but might also influence the mating system of such populations. Any potential increase in the selfing rate due to cross-pollination among ramets of the same genet may, in turn, increase the likelihood of homoploid hybrid speciation. [source] Neuroendocrine Function and Chronic Inflammatory StressEXPERIMENTAL PHYSIOLOGY, Issue 5 2002Michael Harbuz The factors regulating susceptibility and severity of autoimmune diseases are poorly understood. That neuroendocrine factors are critical modulators in this regard is self-evident. For example, there are major gender differences in susceptibility with women at greater risk than men of, for example, rheumatoid arthritis (RA) and multiple sclerosis (MS). The hypothalamo-pituitary-adrenal (HPA) axis has rightly attracted a considerable amount of attention. Of particular interest has been the hypothesis that susceptibility to autoimmune disease may be related to an impaired responsiveness of the HPA axis; that is, an inability to mount an appropriate cortisol response with which to down-regulate the immune system might allow the immune system to rampage unchecked and attack self. This hypothesis links regulation of the release from the adrenal gland of the potent anti-inflammatory glucocorticoids to the disease process. Endogenous glucocorticoids are crucial for the regulation of the severity of the disease process. The hypothesis proposing a link between a hyporesponsive HPA axis and susceptibility to disease is compelling. However, evidence from a number of sources has suggested that this may not be the entire story and alterations in the activity of the HPA axis have not been consistently observed in patients with RA. This review will concentrate on recent findings concerning the HPA axis in determining susceptibility to, and in regulating the severity of, inflammatory processes in autoimmune disease. These studies have revealed that a single exposure to endotoxin can confer protection to subsequent development of inflammation in an arthritis model in both neonatal and adult rats. Behavioural differences within a single population of rats are associated with differences in the plasma corticosterone responses to stress. However, relative hyporesponsiveness is not reflected by an increase in the severity of inflammation. In humans with RA the dexamethasone-corticotrophin-releasing factor (CRF) test has revealed two distinct sub-populations of patients. Studies in patients with MS have shown that this is not related to depression but rather to the severity of the disease. A better understanding of these complex neuroendocrine interactions may lead to novel clinical interventions. [source] The effect of overload on the fatigue crack growth behaviour of 304 stainless steel in hydrogenFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 1 2001M. H. Kelestemur Fatigue crack growth (FCG) behaviour and its characteristics following tensile overloads were investigated for AISI 304 stainless steel in three different atmospheres; namely dry argon, moist air and hydrogen. The FCG tests were performed by MTS 810 servohydraulic machine. CT specimens were used for the tests and crack closure measurements were made using an extensometer. FCG rates of 304 stainless steel at both dry argon and moist air atmospheres have shown almost the same behaviour. In other words, the effect of moisture on FCG of this material is very small. However, in a hydrogen atmosphere, the material showed considerably higher crack growth rate in all regimes. In general, for all environments, the initial effect of overloads was to accelerate the FCG rate for a short distance (less than a mm) after which retardation occurred for a considerable amount of time. The main causes for retardation were found as crack blunting and a long reinitiation period for the fatigue crack. Regarding the environmental effect, the overload retardation was lowest in a hydrogen atmosphere. This low degree of retardation was explained by a hydrogen embrittlement mechanism. In a general sense, hydrogen may cause a different crack closure mechanism and hydrogen induced crack closure has come in to the picture. Scanning electron microscope and light microscope examinations agreed well with the above results. [source] Identity of active methanotrophs in landfill cover soil as revealed by DNA-stable isotope probingFEMS MICROBIOLOGY ECOLOGY, Issue 1 2007Aurélie Cébron Abstract A considerable amount of methane produced during decomposition of landfill waste can be oxidized in landfill cover soil by methane-oxidizing bacteria (methanotrophs) thus reducing greenhouse gas emissions to the atmosphere. The identity of active methanotrophs in Roscommon landfill cover soil, a slightly acidic peat soil, was assessed by DNA-stable isotope probing (SIP). Landfill cover soil slurries were incubated with 13C-labelled methane and under either nutrient-rich nitrate mineral salt medium or water. The identity of active methanotrophs was revealed by analysis of 13C-labelled DNA fractions. The diversity of functional genes (pmoA and mmoX) and 16S rRNA genes was analyzed using clone libraries, microarrays and denaturing gradient gel electrophoresis. 16S rRNA gene analysis revealed that the cover soil was mainly dominated by Type II methanotrophs closely related to the genera Methylocella and Methylocapsa and to Methylocystis species. These results were supported by analysis of mmoX genes in 13C-DNA. Analysis of pmoA gene diversity indicated that a significant proportion of active bacteria were also closely related to the Type I methanotrophs, Methylobacter and Methylomonas species. Environmental conditions in the slightly acidic peat soil from Roscommon landfill cover allow establishment of both Type I and Type II methanotrophs. [source] ,Have You Got a Boyfriend or are You Single?': On the Importance of Being ,Straight' in Organizational ResearchGENDER, WORK & ORGANISATION, Issue 3 2006Attila Bruni The article focuses on heterosexuality as a covert feature of organization studies as well as of organizational research. In fact, while organization studies have discussed the gendered and the gendering aspects of organizational practices and organizational theory, the implication of heterosexuality has yet to receive intensive analysis in these fields. And while the mutual and reflexive constitution of the observer and the observed has been the topic of a considerable amount of research, the dimension of (heterosexual) desire in this process of mutual constitution is still largely unexplored. Referring to three different episodes that occurred while the author was doing organizational ethnography, the article suggests that a heterosexual model of desire is called into action both in organizational and research activities and that focusing on it can be an occasion to question not only the gender (and heterosexual) biases of organizational practices but also the way in which gender and sexuality are mobilized while doing research. In particular, on the basis of the concept of cathexis, the article shows how heterosexuality is learnt and enacted as a situated practice and through a variety of processes: performing power, negotiating and displaying that one belongs to an organizational culture, obscuring the hetero-normativity of professional identities and neglecting the emotional engagement that characterizes research activities and that exposes the researcher to an otherwise vulnerable position. [source] Fine mapping of a sedative-hypnotic drug withdrawal locus on mouse chromosome 11GENES, BRAIN AND BEHAVIOR, Issue 1 2006H. M. Hood We have established that there is a considerable amount of common genetic influence on physiological dependence and associated withdrawal from sedative-hypnotic drugs including alcohol, benzodiazepines, barbiturates and inhalants. We previously mapped two loci responsible for 12 and 9% of the genetic variance in acute alcohol and pentobarbital withdrawal convulsion liability in mice, respectively, to an approximately 28-cM interval of proximal chromosome 11. Here, we narrow the position of these two loci to a 3-cM interval (8.8 Mb, containing 34 known and predicted genes) using haplotype analysis. These include genes encoding four subunits of the GABAA receptor, which is implicated as a pivotal component in sedative-hypnotic dependence and withdrawal. We report that the DBA/2J mouse strain, which exhibits severe withdrawal from sedative-hypnotic drugs, encodes a unique GABAA receptor ,2 subunit variant compared with other standard inbred strains including the genetically similar DBA/1J strain. We also demonstrate that withdrawal from zolpidem, a benzodiazepine receptor agonist selective for ,1 subunit containing GABAA receptors, is influenced by a chromosome 11 locus, suggesting that the same locus (gene) influences risk of alcohol, benzodiazepine and barbiturate withdrawal. Our results, together with recent knockout studies, point to the GABAA receptor ,2 subunit gene (Gabrg2) as a promising candidate gene to underlie phenotypic differences in sedative-hypnotic physiological dependence and associated withdrawal episodes. [source] Optimal treatment of hypertension in the elderly: A Korean perspectiveGERIATRICS & GERONTOLOGY INTERNATIONAL, Issue 1 2008Kwang-Il Kim With the progression of the aging population, common diseases of the elderly have become the center of attention in most developed countries. Hypertension is one of the most common morbid conditions in the elderly and has a great impact on their health status because it is the main risk factor of cardiovascular and cerebrovascular diseases. However, a considerable amount of uncertainty remains regarding hypertension in the elderly, such as the benefits of hypertension control in oldest-old populations, the optimal level of blood pressure control, and the efficacy of antihypertensive drugs for the prevention of cognitive dysfunction. While there are many controversial issues concerning the optimal management of hypertension in the elderly, the number of elderly hypertensive patients that require treatment is expected to increase due to the aging population. As a result, knowledge regarding the mechanisms of hypertension in the elderly and specific consideration in managing hypertensive elderly patients are needed to improve the clinical outcome. Furthermore, new therapeutic interventions that are aimed at attenuating age-related vascular changes should be investigated, because hypertension in the elderly, especially isolated systolic hypertension has specific characteristics of increased arterial stiffness in most cases. [source] Soil piping and catchment responseHYDROLOGICAL PROCESSES, Issue 12 2010J. A. A. Jones Abstract Over the 40 years, since soil piping was first considered to be a potential factor in the hydrological response of catchments, research has revealed a considerable amount about its hydrological role and its geographical, climatic and pedological distribution. Piping has been shown to be a major factor supporting the hypothesis that subsurface flow can be a significant contributor to quickflow by field experiments ranging from the United Kingdom to Canada, India and China. This research has demonstrated that, at least in some areas, soil pipes may contribute up to nearly 50% of stormwater discharge. Piping processes therefore merit inclusion within rainfall,runoff simulation models, but this has yet to be achieved. Some progress has been made in modelling pipeflow itself, but integration within a catchment model presents major problems, not least in quantifying or parameterizing the nature and distribution of pipe networks. The wider environmental implications of soil piping are also only just beginning to be recognized. These range from the effects of changing residence times on water chemistry, especially on the acidification of surface waters, to the effects of hillslope drainage patterns on soil development and vegetation diversity. Copyright © 2010 John Wiley & Sons, Ltd. [source] An adaptive control system using the fuzzy theory for transient multi-physics numerical simulations,INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 6-8 2007Toshiharu Muramatsu Abstract An adaptive control system to yield optimum time step sizes was developed using the fuzzy theory for transient multi-physics numerical simulations. Applications of the control system reveal considerable amount of the computing time savings, typically by 50,75% of the computing time required when the time step size was not controlled by the system. The result obtained in this work is very encouraging in the sense that the adaptive control system would be used as one of the efficient measures for saving computing time when one wishes to perform extremely large-scale computations in transient multi-physics numerical simulations. Copyright © 2007 John Wiley & Sons, Ltd. [source] Reliability of power stations: Stochastic versus derated power approachINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 2 2004Kris R. Voorspools Abstract Consideration of the eventual forced outage of individual power stations leads to a large number of possible states of the power generating system, all with their own probability. It is possible to design a stochastic method to properly take into account all of these possibilities and to weigh them accordingly. In broader energy models, instead of these stochastic techniques that require a considerable amount of calculation time, mostly approximative static simplified methods are applied. Up till now, these simplified techniques have not been validated. The scope of this paper is to check their validity. Therefore, two approaches are compared: a complete stochastic approach and a method based on the derated power (which is the nominal power multiplied with the average availability) of the individual plants. The conclusion of this comparison is that derated power may be used in energy modelling instead of the complicated stochastic approach. The error made is very small and the correlation between the unserved load probability functions obtained by both methods is excellent. Copyright © 2004 John Wiley & Sons, Ltd. [source] Highly Selective Oxidation of Alkylphenols to Benzoquinones with Hydrogen Peroxide over Silica-Supported Titanium Catalysts: Titanium Cluster Site versus Titanium Single SiteADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2009Oxana Abstract Titanium-silica catalysts have been prepared by supporting titanium(IV) precursors with different nuclearity {mononuclear titanocene dichloride Ti(Cp)2Cl2, dinuclear titanium diethyl tartrate and the tetranuclear titanium peroxo complex (NH4)8[Ti4(C6H4O7)4(O2)4],8,H2O} onto the surface of silica materials with different textural characteristics. The supported catalysts have been explored as highly active and reusable catalysts for the oxidation of 2,3,6-trimethylphenol (TMP) and 2,6-dimethylphenol (DMP) to 2,3,5-trimethyl-1,4-benzoquinone (TMBQ, vitamin E key intermediate) and 2,6-dimethyl-1,4-benzoquinone (DMBQ), respectively, using aqueous hydrogen peroxide as green oxidant. Catalysts prepared by grafting mononuclear Ti(Cp)2Cl2 revealed a strong dependence of the product selectivity on the surface concentration of titanium active centers. Mesoporous materials with titanium surface concentration in the range of 0.6,1.0,Ti/nm2 were identified as optimal catalysts for the transformation of alkylphenols to benzoquinones. Catalysts having <0.6,Ti/nm2 produced a mixture of benzoquinones and dimeric by-products. Conversely, when di-/tetranuclear titanium precursors were employed for the catalyst preparation, a diminution of the titanium surface concentration had no impact on the benzoquinone selectivity, which was typically as high as 96,99%. DR-UV spectroscopic studies revealed that the catalysts capable of producing alkylbenzoquinones with nearly quantitative yields possess titanium dimers and/or subnanometer-size clusters homogeneously distributed on a silica surface. On the contrary, catalysts with isolated titanium sites give a considerable amount of dimeric by-products. This is the first example which clearly demonstrates the advantages of titanium cluster-site catalysts over titanium single-site catalysts in hydrogen peroxide-based selective oxidation reaction. [source] Chronic, painful lower extremity wounds: postoperative pain management through the use of continuous infusion of regional anaesthesia supplied by a portable pump deviceINTERNATIONAL WOUND JOURNAL, Issue 3 2010Christy L Scimeca Reducing and preventing postoperative pain are currently a topic of great interest. There are different modalities for providing analgesia that can provide an alternative or adjunct to opioid therapy. One mode of therapy involves the use of portable pain pump devices that can deliver continuous local anaesthesia directly to the site of interest. A considerable amount of attention in literature has been dedicated to using regional anaesthesia postoperatively for various surgical applications. However, to our knowledge, little or no work has been published concerning the use of infusion of regional anaesthesia in the treatment of painful lower extremity wounds. We present a case report of a 55-year-old gentleman with a complex past medical history, 2-year history of opioid dependency and a 2-week history of intractable pain associated with the combination of debilitating painful diabetic neuropathy and painful lower extremity wounds. After surgical debridement of the lower extremity wounds, substantial analgesia was achieved postoperatively through the implantation of a portable direct infusion pump device. The device supplied 2 ml/hour of 0·25% bupivacaine and resulted in a reduction in pain within the first hour of implantation. Although the device achieved maximal analgesia at 6 hours, we found that this could have been likely reduced through the use of a 5-ml bolus dose of 0·25% bupivacaine at the time of implantation. The device provided sufficient analgesia to the patient without any observed adverse effects, and showed significant potential in avoiding an increase in his requirement for other systemic analgesia including opioids. [source] Psychodynamic and Neurological Perspectives on ADHD: Exploring Strategies for Defining a PhenomenonJOURNAL FOR THE THEORY OF SOCIAL BEHAVIOUR, Issue 4 2001Adam Rafalovich This article is a discourse analysis of two historical inquiries into what clinici-ans today call attention deficit hyperactivity disorder (ADHD). Of primary con-cern in this regard are psychodynamic perspectives towards ADHD symptoms, championed by psychoanalysts and psychologists, and neurological perspectives towards ADHD, which continue to favor a purely physiological approach to understanding the disorder. Those within the psychodynamic camp are inclined to view ADHD as an interactional difficulty between self and social environment - a condition best remedied by psychotherapy. Those within the neurological camp see ADHD as a specific brain process, whose effective treatment depends upon adequate psychopharmacology. This essay argues that both psychodynamic and neurological perspectives towards ADHD have strategized to legitimate one perspective through the expulsion of the other. Within the current era of ADHD nomenclature and treatment it is clear that neurological perspectives dominate the debate. However, neurological perspectives continue to be haunted by a considerable amount of skepticism, both nationally and internationally. Because of this it would be difficult to assert that neurological perspectives, though winning the "legitimation race" in contemporary understandings of ADHD, are entirely monolithic sources of ADHD knowledge. [source] Completion of crystal structures from powder data: the use of the coordination polyhedraJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 6 2000Angela Altomare Direct methods applied to powder diffraction data often provide well located heavy atoms and unreliable light-atom positions. The completion of the crystal structure is then not always straightforward and may require a considerable amount of user intervention. The heavy-atom connectivity provided by the trial solution may be used to guess the nature of the coordination polyhedra. A Monte Carlo procedure is described which, in the absence of a well defined structural model, is able to locate the light atoms correctly under the restraints of the experimental heavy-atom connectivity model. The correctness of the final model is assessed by criteria based on the agreement between the whole experimental diffraction pattern and the calculated one. The procedure requires little CPU computing time and has been implemented as a routine of EXPO [Altomare et al. (1999). J. Appl. Cryst.32, 339,340]. The method has proved to be sufficiently robust against the distortion of the coordination polyhedra and has been successfully applied to some test structures. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||