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Kinds of Favourable Terms modified by Favourable Selected AbstractsModelling chorotypes of invasive vertebrates in mainland SpainDIVERSITY AND DISTRIBUTIONS, Issue 2 2008Raimundo Real ABSTRACT We investigated the existence of chorotypes , assemblages of species with similar geographical ranges , of invasive species in a host territory, and their potential use to advocate similar control or management strategies for species in the same chorotype. We analysed the distribution of 13 exotic terrestrial vertebrate species (six birds, six mammals, and one reptile) with well-known distributions in mainland Spain. We used the presence/absence data on a grid of 10 km × 10 km UTM cells from the Atlases of terrestrial vertebrates of Spain. These data were aggregated to a grid of 50 km × 50 km UTM cells, because it entailed no loss of meaningful information and allowed dealing with a much lower number of cells. Using cluster analysis and a probabilistic assessment of the classification, we identified seven significant chorotypes: four multispecific and three monospecific. The compound chorotypes grouped together species that tended to share certain characteristics about their introduction, release cause, establishment, and spread. We modelled the chorotypes using a favourability function based on a generalized linear model and 31 variables related to spatial situation, topography, lithology, climatic stability, energy availability, water availability, disturbances, productivity, and human activity. Climatic factors affected the favourability for every chorotype, whereas human variables had a high influence in the distribution of three chorotypes involving eight species. On the basis of these variables, we identified favourable areas for all the chorotypes in mainland Spain. The favourability for a chorotype in an area may be a useful criterion for evaluating the local conservation concern due to the whole set of species. Favourable but unoccupied areas can be used to infer possible colonization areas for each chorotype. We recommend using chorotypes to optimize broad-scale surveillance of invasive species. [source] Regional climate modulates the canopy mosaic of favourable and risky microclimates for insectsJOURNAL OF ANIMAL ECOLOGY, Issue 3 2007SYLVAIN PINCEBOURDE Summary 1,One major gap in our ability to predict the impacts of climate change is a quantitative analysis of temperatures experienced by organisms under natural conditions. We developed a framework to describe and quantify the impacts of local climate on the mosaic of microclimates and physiological states of insects within tree canopies. This approach was applied to a leaf mining moth feeding on apple leaf tissues. 2,Canopy geometry was explicitly considered by mapping the 3D position and orientation of more than 26 000 leaves in an apple tree. Four published models for canopy radiation interception, energy budget of leaves and mines, body temperature and developmental rate of the leaf miner were integrated. Model predictions were compared with actual microclimate temperatures. The biophysical model accurately predicted temperature within mines at different positions within the tree crown. 3,Field temperature measurements indicated that leaf and mine temperature patterns differ according to the regional climatic conditions (cloudy or sunny) and depending on their location within the canopy. Mines in the sun can be warmer than those in the shade by several degrees and the heterogeneity of mine temperature was incremented by 120%, compared with that of leaf temperature. 4.,The integrated model was used to explore the impact of both warm and exceptionally hot climatic conditions recorded during a heat wave on the microclimate heterogeneity at canopy scale. During warm conditions, larvae in sunlight-exposed mines experienced nearly optimal growth conditions compared with those within shaded mines. The developmental rate was increased by almost 50% in the sunny microhabitat compared with the shaded location. Larvae, however, experienced optimal temperatures for their development inside shaded mines during extreme climatic conditions, whereas larvae in exposed mines were overheating, leading to major risks of mortality. 5,Tree canopies act as both magnifiers and reducers of the climatic regime experienced in open air outside canopies. Favourable and risky spots within the canopy do change as a function of the climatic conditions at the regional scale. The shifting nature of the mosaic of suitable and risky habitats may explain the observed uniform distribution of leaf miners within tree canopies. [source] AFRICA WORLD BUSINESS CONGRESS: Africa Favourable for InvestmentsAFRICA RESEARCH BULLETIN: ECONOMIC, FINANCIAL AND TECHNICAL SERIES, Issue 2 2009Article first published online: 7 APR 200 No abstract is available for this article. [source] Psychotherapy for depression among children and adolescents: a systematic reviewACTA PSYCHIATRICA SCANDINAVICA, Issue 2 2007N. Watanabe Objective:, To examine the clinical benefit, the harm and the cost-effectiveness of psychotherapies in comparison with no treatment, waiting-list controls, attention-placebos, and treatment as usual in depressed youths. Method:, Meta-analyses were undertaken by using data from all relevant randomized-controlled trials identified by a comprehensive literature search. The primary outcome was relative risk (RR) of response. Results:, We identified 27 studies containing 35 comparisons and 1744 participants. At post-treatment, psychotherapy was significantly superior (RR = 1.39, 95% CI 1.18,1.65, P = 0.0001, number-needed to treat 4.3). There was an evidence of the existence of small study effects, including a publication bias (P < 0.001). The superiority of psychotherapy was no longer statistically significant (1.18 [0.94,1.47], P = 0.15) at 6-month follow-up. None of the studies reported adverse effects or cost-effectiveness outcomes. Conclusion:, Although the findings were biased by some small positive trials, psychotherapies appear to help depressed youths for the short term, but are no longer significantly favourable at 6-month follow-up. [source] Neurological recovery in obstetric brachial plexus injuries: an historical cohort studyDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 2 2004Agnes F Hoeksma MD An historical cohort study was conducted to investigate the rate and extent of neurological recovery in obstetric brachial plexus injury (OBPI) and to identify possible prognostic factors in a cohort of children with OBPI from birth to 7 years. All children (n=56; 31 females, 25 males) with OBPI were evaluated at fixed time intervals by one examiner. They underwent a final neurological examination at a mean age of 3 years 10 months (range 1 to 7 years). Neurological outcome was not as favourable as is often reported: complete neurological recovery occurred in 37 out of 56 children (66%). In half of these there was delayed recovery, in which case complete neurological recovery was assessed from 1.5 to 16 months of age (median age 6.5 months, SD 4.2 months). External rotation and supination were the last to recover and recovered the least. Although biceps function at three months was considered to be the best indicator for operative treatment, external rotation and supination were found to be better in predicting eventual complete recovery. Initial symptoms directly post partum were not found to be prognostic. Functional outcome was mainly reported to be good. [source] Heel ulcers don't heal in diabetes.DIABETIC MEDICINE, Issue 9 2005Or do they? Abstract Aim To obtain information on outcome of heel ulcers in diabetes. Methods Data were recorded prospectively on all patients with heel ulcers who were referred to a specialist multidisciplinary clinic between 1 January 2000 and 30 November 2003. Outcomes were assessed on 31 March 2004. Results There were 157 heel ulcers in the patients referred in the period. Three ulcers were excluded from analysis because of associated osteomyelitis. Of 154 remaining ulcers (121 limbs; 97 patients, 55 male; mean age 68.5 ± 12.8 sd years), 101 (65.6%) healed after a median (range) 200 (24,1225) days. Of 53 non-healed ulcers, 11 (7.1% of 154) were resolved by major amputation, 30 (19.5% of 154) were unhealed at time of patient's death, and 12 (7.8% of 154) remained unhealed. Ulcers healed in 59 of 97 affected patients (60.8%). Twenty-six patients (26.8% of 97) died during the period, of whom 20 died with ulcers unhealed. Worse outcomes were observed in larger ulcers (P = 0.001, Mann,Whitney U -test = 1883.5) and limbs with clinical evidence of peripheral arterial disease (P = 0.001, Mann,Whitney U -test = 1163.00). Backward step-wise logistic regression analysis showed 70.1% of healing could be predicted from these two baseline characteristics. Conclusions The common perception that ,heel ulcers don't heal' is not reflected in clinical practice. Outcome is generally favourable even in a population often affected by serious comorbidity and with limited life expectancy. These data can be used to help define management plans, as well as a basis for counselling of the individual patient. [source] What shapes Eurasian lynx distribution in human dominated landscapes: selecting prey or avoiding people?ECOGRAPHY, Issue 4 2009Mathieu Basille In the multi-use landscape of southern Norway, the distribution of lynx is likely to be determined both by the abundance of their favoured prey , the roe deer , and the risk associated with the presence of humans because most lynx mortalities are caused by humans (recreational harvest, poaching, vehicle collisions). We described the distribution of the reproductive portion of the lynx population based on snow-track observations of females with dependent kittens collected over 10,yr (1997,2006) in southern Norway. We used the ecological-niche factor analysis to examine how lynx distribution was influenced by roe deer, human activity, habitat type, environmental productivity and elevation. Our first prediction that lynx should be found in areas of relatively high roe deer abundance was supported. However, our second prediction that lynx should avoid human activity was rejected, and lynx instead occupied areas more disturbed in average than those available (with the exception of the most densely occupied areas). Lynx, however, avoided the most disturbed areas and our third prediction of a trade-off between abundance of prey and avoidance of human activity was supported. On the one hand, roe deer in the most disturbed areas benefit to a large extent from current human land use practices, potentially allowing them to escape predation from lynx. On the other hand, the situation is not so favourable for the predators who are restricted in competition refuges with medium to low prey densities. The consequence is that lynx conservation will have to be achieved in a human modifed environment where the potential for a range of conflicts and high human-caused mortality will remain a constant threat. [source] Spatial variation in population density across the geographical range in helminth parasites of yellow perch Perca flavescensECOGRAPHY, Issue 5 2007Robert Poulin The abundance of a species is not constant across its geographical range; it has often been assumed to decrease from the centre of a species' range toward its margins. The central assumption of this "favourable centre" model is tested for the first time with parasites, using different species of helminth parasites exploiting fish as definitive hosts. Data on prevalence (percentage of hosts that are infected) and abundance (mean no. parasites per host) were compiled for 8 helminth species occurring in 23 populations of yellow perch Perca flavescens, from continental North America. For each parasite species, correlations were computed between latitude and both local prevalence and abundance values. In addition, the relationships between the relative prevalence or abundance in one locality and the distance between that locality and the one where the maximum value was reported, were assessed separately for each species to determine whether abundance tends to decrease away from the presumed centre of the range, where it peaks. For both the cestode Proteocephalus pearsei and the acanthocephalan Leptorhynchoides thecatus, there was a positive relationship between prevalence or abundance and the latitude of the sampled population. There was also a significant negative relationship between relative prevalence and the distance from the locality showing the maximum value in P. pearsei, but no such pattern was observed for the other 7 parasite species. Since this single significant decrease in prevalence with increasing distance from the peak value may be confounded by a latitudinal gradient, it appears that the distribution of abundance in parasites of perch does not follow the favourable centre model. This means that the environmental variables affecting the density of parasites (host availability, abiotic conditions) do not show pronounced spatial autocorrelation, with nearby sites not necessarily providing more similar conditions for the growth of parasite populations than distant sites. [source] Post-fire recovery of ant communities in Submediterranean Pinus nigra forestsECOGRAPHY, Issue 2 2006Anselm Rodrigo This study analyzes the variations in the structure and composition of ant communities in burned Pinus nigra forests in central Catalonia (NE Spain). Pinus nigra forests do not recover after fire, changing to shrublands and oak coppices. For this reason, we suggest that ant communities of burned P. nigra forests will change after fire, because the post-fire scenario, in particular with the increase of open areas, is different to the unburned one, and more favourable for some species than for others. In four locations previously occupied by P. nigra forests where different fires occurred 1, 5, 13 and 19 yr before the sampling, we sampled the structure and composition of ant communities with pitfall traps, tree traps and net sweeping in unburned plots and in plots affected by canopy and understory fire. The results obtained suggest that canopy and understory fire had little effect on the structure of ant communities. Thus, many variables concerning ant communities were not modified either by fire type (understory or canopy fire) or by time since fire. However, a number of particular species were affected, either positively or negatively, by canopy fire: three species characteristic of forest habitats decreased after fire, while eight species characteristic of open habitats increased in areas affected by canopy fire, especially in the first few years after fire. These differences in ant community composition between burned and unburned plots imply that the maximum richness is achieved when there is a mixture of unburned forests and areas burned with canopy fire. Moreover, as canopy cover in P. nigra forests burned with canopy fire is not completed in the period of time studied, the presence of the species that are characteristic of burned areas remains along the chronosequence studied, while the species that disappear after fire do not recover in the period of time considered. Overall, the results obtained indicate that there is a persistent replacement of ant species in burned P. nigra forests, as is also the case with vegetation. [source] Wide-area estimates of saltcedar (Tamarix spp.) evapotranspiration on the lower Colorado River measured by heat balance and remote sensing methods,,ECOHYDROLOGY, Issue 1 2009Pamela L. Nagler Abstract In many places along the lower Colorado River, saltcedar (Tamarix spp) has replaced the native shrubs and trees, including arrowweed, mesquite, cottonwood and willows. Some have advocated that by removing saltcedar, we could save water and create environments more favourable to these native species. To test these assumptions we compared sap flux measurements of water used by native species in contrast to saltcedar, and compared soil salinity, ground water depth and soil moisture across a gradient of 200,1500 m from the river's edge on a floodplain terrace at Cibola National Wildlife Refuge (CNWR). We found that the fraction of land covered (fc) with vegetation in 2005,2007 was similar to that occupied by native vegetation in 1938 using satellite-derived estimates and reprocessed aerial photographs scaled to comparable spatial resolutions (3,4 m). We converted fc to estimates of leaf area index (LAI) through point sampling and destructive analyses (r2 = 0·82). Saltcedar LAI averaged 2·54 with an fc of 0·80, and reached a maximum of 3·7 with an fc of 0·95. The ranges in fc and LAI are similar to those reported for native vegetation elsewhere and from the 1938 photographs over the study site. On-site measurements of water use and soil and aquifer properties confirmed that although saltcedar grows in areas where salinity has increased much better than native shrubs and trees, rates of transpiration are similar. Annual water use over CNWR was about 1·15 m year,1. Copyright © 2008 John Wiley & Sons, Ltd. [source] Holly leaf-miners on two continents: what makes an outbreak species?ECOLOGICAL ENTOMOLOGY, Issue 2 2001Sabine Eber Summary 1. Some herbivore species periodically undergo damaging, high-density outbreak phases followed by less damaging low-density phases. Others maintain steady, low to moderate density levels that do little damage to their hosts. 2. Two closely related holly leaf-miner species were compared that share many ecological traits and have very similar life cycles, but only one of which exhibits outbreaks. Phytomyza ilicicola in the eastern U.S.A. varied widely in mortality and infestation levels, reaching local densities of over 10 mines per leaf. In contrast, Phytomyza ilicis in the U.K. showed low infestation and high mortality at all sites. Using data from the literature and from field studies, the factors responsible for these contrasting dynamics were sought. 3. Phytomyza ilicicola oviposits into the leaf lamina, and experiences weak larval competition only at high densities. Phytomyza ilicis oviposits into the leaf midrib, which leads to high mortality of young larvae before mine formation. Multiply mined leaves were therefore very common in P. ilicicola but rare in P. ilicis. 4. Differences in the parasitoid complexes of the two systems accounted for further differences in survival to adulthood. The main (larval) parasitoid, which was found to impose high, density-dependent mortality on P. ilicis, is missing on P. ilicicola. It is replaced by an egg,pupal parasitoid, which varies in its impact at differe,t sites. Multiple emergence of adults from multiply mined leaves is therefore widespread in P. ilicicola but does not occur in P. ilicis. 5. The differences in oviposition behaviour and in the parasitoid complexes are likely to allow P. ilicicola to outbreak when habitat conditions are favourable, while P. ilicis is always tightly regulated. [source] The ratification of ILO conventions: A hazard rate analysisECONOMICS & POLITICS, Issue 3 2001Bernhard Boockmann There are over 180 ILO conventions in many areas of labour law, industrial relations and social security, but they are not ratified universally: for the conventions adopted between 1975 and 1995, the cumulative probability of ratification is about 13 percent 10 years after their adoption. In this paper, the ratification decision is understood as a transition between two states. Using duration analysis, we identify circumstances which are favourable to this transition. For industrialized countries, the ratification of ILO conventions is shown to depend on internal political factors such as government preferences or the power of left-wing parties in parliament. For developing countries, economic costs of ratification have a significant impact. There is no evidence for external pressure in favour of ratification. Among industrialized member states, there is a clear downward trend in estimated ratification probabilities over the last two decades. [source] The cost-effectiveness of antidepressants for smoking cessation in chronic obstructive pulmonary disease (COPD) patientsADDICTION, Issue 12 2009Constant P. Van Schayck ABSTRACT Objectives In healthy smokers, antidepressants can double the odds of cessation. Because of its four times lower costs and comparable efficacy in healthy smokers, nortriptyline appears to be favourable compared to bupropion. We assessed which of both drugs was most effective and cost-effective in stopping smoking after 1 year compared with placebo among smokers at risk or with existing chronic obstructive pulmonary disease (COPD). Methods A total of 255 participants, aged 30,70 years, received smoking cessation counselling and were assigned bupropion, nortriptyline or placebo randomly for 12 weeks. Prolonged abstinence from smoking was defined as a participant's report of no cigarettes from week 4 to week 52, validated by urinary cotinine. Costs were calculated using a societal perspective and uncertainty was assessed using the bootstrap method. Results The prolonged abstinence rate was 20.9% with bupropion, 20.0% with nortriptyline and 13.5% with placebo. The differences between bupropion and placebo [relative risk (RR) = 1.6; 95% confidence interval (CI) 0.8,3.0] and between nortriptyline and placebo (RR = 1.5; 95% CI 0.8,2.9) were not significant. Severity of airway obstruction did not influence abstinence significantly. Societal costs were ,1368 (2.5th,97.5th percentile 193,5260) with bupropion, ,1906 (2.5th,97.5th 120,17 761) with nortriptyline and ,1212 (2.5th,97.5th 96,6602) with placebo. Were society willing to pay more than ,2000 for a quitter, bupropion was most likely to be cost-effective. Conclusions Bupropion and nortriptyline seem to be equally effective, but bupropion appears to be more cost-effective when compared to placebo and nortriptyline. This impression holds using only health care costs. As the cost-effectiveness analyses concern some uncertainties, the results should be interpreted with care and future studies are needed to replicate the findings. [source] Production of a Laccase and Decrease of the Phenolic Content in Canola Meal during the Growth of the Fungus Pleurotus ostreatus in Solid State Fermentation ProcessesENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 1 2004J. Hu Abstract Solid state fermentation of canola meal was carried out with the fungus Pleurotus ostreatus DAOM 197961, which is a producer of laccase. The aim of this study was to examine the effects of moisture content, inoculum size, homogenisation of inoculum and particle size of canola meal on the growth of the fungus, the production of a laccase and the decrease of the content of sinapic acid esters (SAE) in a solid state process. The results showed that the optimum moisture content, which was varied in the media between 50% and 75%, for the growth and enzyme production was 60%. The initial rate of SAE content decrease was faster in the media with 70% and 75% moisture than in those with lower moisture levels. In the study of the effects of inoculum concentration in the range of 1.1 mg to 5.5 mg/g of the medium, it was found that larger amounts of biomass and enzyme were produced in the media with inoculum concentrations from 1.1 mg to 3.3 mg/g of the medium than in the media with a higher inoculum concentration. The final and approximately the same concentrations of SAE were reached at the same time regardless of the inoculum concentration. Considering that the fungus formed pellets under the conditions at which it was grown during the inoculum preparation, it was necessary to break them by homogenisation prior to their utilisation as an inoculum. The homogenisation was carried out during a period between 15s and 200s. Although higher biomass concentrations and enzyme activities were obtained in the media which were inoculated with the inoculum homogenised for 15s and 30s, the maximum enzyme activities and biomass concentrations were reached in the media inoculated with the inoculum, which was homogenised for 120s and 200s. The time of inoculum homogenisation did not influence the kinetics of the SAE decrease. When the effects of the particle size of canola meal on the process were studied, it was found that larger particles of the meal in the solid media were more favourable for the production of the biomass and enzyme, and for a faster decrease of the SAE content than those of smaller sizes. From the obtained results it can be concluded that the tested variables have a significant influence on the growth of the fungus Pleurotus ostreatus DAOM 197961, the production of laccase and the decrease of the SAE content in canola meal. The data could be useful for the development of a solid state process for the production of laccase and for the decrease of the phenolics content in canola meal. [source] Selection of hibernation sites by Anthonomus pomorum: preferences and ecological consequencesENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2000St. Toepfer Abstract The apple blossom weevil, Anthonomus pomorum (L.) (Coleoptera: Curculionidae), has a long period of aestivo-hibernation in the adult stage lasting from summer to early spring of the following year. Potential hibernation sites within an apple orchard consist of high-stem rough-bark trees or dwarf smooth-bark trees. Field release-recapture experiments in 2 consecutive years showed that 64 and 47% of the weevils remained in the vicinity of the release sites in an area of high-stem trees and dwarf trees, respectively. The dispersing weevils moved over an average distance of 5.5 m in the dwarf tree area, as compared to 3.8 m in the high-stem tree area. The prevalent direction of dispersal was along tree rows in both areas. Some weevils displayed, after release in mid-July, a directional dispersal to the adjacent forests. Others, released in the dwarf tree area, dispersed towards the area of high-stem rough-bark apple trees. Experiments simulating various hibernation sites demonstrated that the litter of dry leaves was the most preferred overwintering shelter, yielding a relatively high survival rate. Branches with rough bark ranked second, while branches with smooth bark, grass and pure soil were not favourable for overwintering. Flight tendency in newly emerged weevils of summer generation was significantly higher in June/July than in August/September. This corresponds to the dispersal behaviour in the field. The timing of spring colonisation of apple trees was similar for weevils overwintering within the orchard and for those from outside. These results suggest that modern, dwarf apple orchards offer unfavourable conditions for overwintering, but that the relatively small proportion of weevils which manage to reach the adjacent forests find optimal hibernation sites there. [source] Localization of processes involved in methanogenic degradation of rice straw in anoxic paddy soilENVIRONMENTAL MICROBIOLOGY, Issue 8 2001Kristin Glissmann In anoxic paddy soil, rice straw is decomposed to CH4 and CO2 by a complex microbial community consisting of hydrolytic, fermenting, syntrophic and methanogenic microorganisms. Here, we investigated which of these microbial groups colonized the rice straw and which were localized in the soil. After incubation of rice straw in anoxic soil slurries for different periods, the straw pieces were removed from the soil, and both slurry and straw were studied separately. Although the potential activities of polysaccharolytic enzymes were higher in the soil slurry than in the straw incubations, the actual release of reducing sugars was higher in the straw incubations. The concentrations of fermentation products, mainly acetate and propionate, increased steadily in the straw incubations, whereas only a little CH4 was formed. In the soil slurries, on the other hand, fermentation products were low, whereas CH4 production was more pronounced. The production of CH4 or of fermentation products in the separated straw and soil incubations accounted in sum for 54,82% of the CH4 formed when straw was not removed from the soil. Syntrophic propionate degradation to acetate, CO2 and H2 was thermodynamically more favourable in the soil than in the straw fraction. These results show that hydrolysis and primary fermentation reactions were mainly localized on the straw pieces, whereas the syntrophic and methanogenic reactions were mainly localized in the soil. The percentage of bacterial relative to total microbial 16S rRNA content was higher on the straw than in the soil, whereas it was the opposite for the archaeal 16S rRNA content. It appears that rice straw is mainly colonized by hydrolytic and fermenting bacteria that release their fermentation products into the soil pore water where they are further degraded to CH4. Hence, complete methanogenic degradation of straw in rice soil seems to involve compartmentalization. [source] Monitoring of Desulfitobacterium frappieri PCP-1 in pentachlorophenol-degrading anaerobic soil slurry reactorsENVIRONMENTAL MICROBIOLOGY, Issue 6 2000M. Lanthier Anaerobic biodegradation of pentachlorophenol (PCP) was studied in rotative bioreactors containing 200 g of PCP-contaminated soil and 250 ml of liquid medium. Reactors were bioaugmented with cells of Desulfitobacterium frappieri strain PCP-1, a bacterium able to dehalogenate PCP to 3-chlorophenol. Cells of strain PCP-1 were detected by quantitative PCR for at least 21 days in reactors containing 500 mg of PCP per kg of soil but disappeared after 21 days in reactors with 750 mg of PCP per kg of soil. Generally, PCP was completely removed in less than 9 days in soils contaminated with 189 mg of PCP per kg of soil. Sorption of PCP to soil organic matter reduced its toxicity and enhanced the survival of strain PCP-1. In some non-inoculated reactors, the indigenous microorganisms of some soils were also able to degrade PCP. These results suggest that anaerobic dechlorination of PCP in soils by indigenous PCP-degrading bacteria, or after augmentation with D. frappieri PCP-1, should be possible in situ and ex situ when the conditions are favourable for the survival of the degrading microorganisms. [source] The effect of metformin on measurements of insulin sensitivity and , cell response in 18 horses and ponies with insulin resistanceEQUINE VETERINARY JOURNAL, Issue 5 2008A. E. Durham Summary Reasons for performing study: Laminitis in equids is a very common debilitating disease, and insulin resistance (IR) and hyperinsulinaemia are increasingly recognised as important predisposing factors. Pharmacological modification of IR and hyperinsulinaemia might reduce the risk of laminitis. Hypothesis: Metformin, a drug commonly prescribed for treatment of human IR, may also decrease IR in equids. Methods: Eighteen horses and ponies with IR and recurrent laminitis were treated with 15 mg/kg bwt metformin per os q. 12 h. Each animal served as its own control by comparing pre- and post treatment proxies for IR, insulin sensitivity (IS) and pancreatic , cell function while controlling for possible dietary and managemental influences on IR. Results: Evidence of significantly improved IS and decreased pancreatic , cell secretion was found following metformin treatment. The magnitude of effect was greater at earlier resampling (6,14 days) than at later times (23,220 days). Apparent subjective clinical benefits were good but less favourable than effects on IR. Conclusions: Metformin is safe and appears to increase IS in equids. Potential relevance: Metformin may be indicated as a treatment for IR in equids. Further studies are required to define appropriate selection of subjects warranting therapy, dosing schedule and pharmacokinetics. [source] Stability of preferences with regard to adjuvant chemotherapy: impact of treatment decision, experience and the passing of timeEUROPEAN JOURNAL OF CANCER CARE, Issue 1 2008S.J.T. JANSEN phd Research has shown that patients' preferences for adjuvant chemotherapy do not change as a result of experience. However, the preferences of experienced patients are usually more favourable than those of inexperienced patients. These results indicate a shift in preferences after the decision to proceed with adjuvant chemotherapy has been made, but before actual experience. We tested this assumption in early-stage breast and colorectal cancer patients. We asked patients to provide their preferences for chemotherapy before surgery and thus before they knew whether chemotherapy would be advised (T1), after surgery but before the start of chemotherapy (T2) and about 1 month after chemotherapy (T3). Patients who did not undergo chemotherapy co-operated at similar points in time. Preferences were measured on a nine-point scale, ranging from (1) ,very strong preference for no chemotherapy' to (9) ,very strong preference for chemotherapy'. As hypothesized, the preferences of patients who would be treated with chemotherapy became more favourable after the treatment decision had been made (n = 7, P = 0.06). The preferences of patients for whom chemotherapy was not part of the treatment plan showed the opposite effect (n = 38, P = 0.03). We did not find any effect of experiencing treatment (n = 22, P = 0.62) or the passing of time (n = 81, P = 0.25) on the stability of preferences. We conclude that the frequently observed discrepancy in treatment preferences between experienced and inexperienced patients seems to be an effect of the treatment decision and not of experience of the treatment. [source] High HDL-cholesterol in women with rheumatoid arthritis on low-dose glucocorticoid therapyEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 9 2008C. García-Gómez ABSTRACT Background, Dyslipidaemia has been described in non-treated rheumatoid arthritis (RA), and improves after therapy with disease modifying anti-rheumatic drugs or glucocorticoids; however, it has generally been perceived that glucocorticoids adversely affect lipid metabolism. The association of low dose glucocorticoid therapy with plasma lipid levels was evaluated in female RA patients. Materials and methods, A cross-sectional study was conducted in 78 female RA patients [mean age: 60 (12) years; mean disease duration: 13 (9) years]. Sixty-five (83%) were on glucocorticoid therapy [total equivalent mean prednisone dose: 5·1 (1·7) mg d,1]. Each patient was assessed through a self-reported questionnaire, structured interview and physical examination. Blood samples were obtained for routine biochemistry, lipid profile and haematological tests. Lipid profiles of RA patients who were and were not on glucocorticoid therapy were compared. Results, Clinical and laboratory features of the two groups of patients were similar, except for the Health Assessment Questionnaire and body mass index, which were significantly higher in the patients on glucocorticoid therapy. These patients had 14·7% higher serum high-density lipoprotein cholesterol (HDL-c) levels than untreated patients (P = 0·043), mainly at the expense of HDL2 subfraction, which was 24·4% higher (P < 0·039), whereas HDL3-c was only 7·4% higher (P = 0·219). Serum levels of glucose and total cholesterol, triglyceride, low-density lipoprotein cholesterol (LDL -c), very low-density lipoprotein cholesterol, apolipoproteins A-I and B were not increased in patients on glucocorticoid therapy. Conclusions, Low dose glucocorticoid therapy in RA patients is associated with an increase in HDL-c, without increasing LDL-c or triglyceride. These lipid changes may overall be considered favourable. [source] Dental undergraduate expectations and opinions of Web-based courseware to supplement traditional teaching methodsEUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 3 2003R. Eynon The rapid growth of Internet for the delivery of information has enabled teaching materials to be placed on websites allowing student access to course material. It is the aim of this paper to evaluate a cohort of dental undergraduate students who have used Web-based courseware in prosthetic dentistry for a semester. A questionnaire was distributed to clinical undergraduate students prior to the use of the prosthetics course to determine their experience of using the World Wide Web (WWW) and their expectations of an online course. A second questionnaire was distributed at the end of 6 months which asked about their usage and opinions of the prosthetics Web-based courseware. The main concerns raised at the beginning of the course were related to computer access, the ability to use computers, the time involved and their conception that the e-course would be an additional burden. The main potential benefits were perceived to be convenience, availability of information and the ability to reinforce or catch up on aspects of the module they did not understand or had missed. Feedback at the end of the year showed that most students had accessed the Web-based courseware site at least once a month and, generally, their comments were favourable, dispelling some of the initial perceived fears. They felt that the website was a quick and convenient way to access information and was a good additional resource. Access to the site and printing information were the main problems raised by the students who had to use a shared cluster. In conclusion, Web-based courseware was felt to be a useful additional resource for students. However, this research showed that sufficient computers and printers must be available for such a resource to become an integrated part of the dental course. [source] Enzymatic fatty acid exchange in glycero-phospholipids,EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 10 2003Patrick Adlercreutz Abstract Lipases can be used to exchange fatty acids in the sn -1 position of glycerophospholipids and phospholipase A2 is useful for the corresponding exchange reaction in the sn -2 position. In both cases, the exchange can be done in a one-step acidolysis process or in a two-step process. In the latter case, the original fatty acid in the desired position is removed by enzymatic hydrolysis or alcoholysis and after isolation of the resulting lysophospholipid, the new fatty acid is introduced, using the same enzyme, in an esterification reaction. Several synthesis examples from the literature are reviewed. Incorporation of a new fatty acid into the sn -1 position is more favourable than incorporation into the sn -2 position because of the magnitudes of the equilibrium constants of the reactions and because lipases can be used at much lower water activity than phospholipase A2. With the consecutive use of both enzymes highly pure products with defined fatty acids in both positions can be obtained. [source] By their words ye shall know them: Language abstraction and the likeability of describersEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 2 2010Karen M. Douglas According to the linguistic category model (LCM), behaviour can be described at concrete (e.g. ,Kath hit Kim') and abstract (e.g. ,Kath is aggressive') levels. Variations in these levels convey information about the person being described and the relationship between that person and the describer. In the current research, we examined the power of language abstraction to create impressions of describers themselves. Results show that describers are seen as less likeable when they use abstract (vs. concrete) language to describe the negative actions of others. Conversely, impressions of describers are more favourable when they opt for abstract descriptions of others' positive behaviours. This effect is partially mediated by the attribution of a communicative agenda to describers. By virtue of these attributional implications, language abstraction is an impression formation device that can impact on the reputation of describers. Copyright © 2009 John Wiley & Sons, Ltd. [source] Reduced pole placement method for cascaded frequency control via dispersed pulse invertersEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 4 2005J. Sachau Abstract For modular power systems, structures with parallel power inverters are favourable in view of both easy expandability and supply security. The inverters' embedded controllers are implementing voltage and frequency droops and the superimposed frequency control is coupled via fieldbus. This is a case where a superimposed control is acting via one or more locally dispersed subimposed control-loops. As the states of the subimposed loops are inaccessible, their feedback is no longer viable. The method of reduced pole placement allows reformulation of the design task as complete state feedback without employing a feedback of the single virtual state that just globally describes the one or more subimposed systems. Results are presented for a robust grid frequency controller acting via dispersed pulse inverters. Copyright © 2005 John Wiley & Sons, Ltd. [source] A prototype store choice and location modelling system using Dempster,Shafer theoryEXPERT SYSTEMS, Issue 5 2002Malcolm Beynon This paper concerns the study of destination choice modelling, more specifically identifying within some area (e.g. a city) the region where a particular store is the most favourable to be visited by individuals. An influence measure is constructed for each individual, which incorporates the modern technique known as Dempster,Shafer theory. Based on the evidence of the shopping destinations of individuals, geographical regions are found for levels of largest belief and plausibility (within Dempster,Shafer theory) for specific stores being the most favourable to visit. Additionally, this method may be used to identify the possible position of new stores, based on regions of most uncertainty or conflict in store choice. A prototype choice modelling system is introduced to enable the series of associated results to be easily visualized and analysed. [source] Thermodynamic analysis of binding of p -substituted benzamidines to trypsinFEBS JOURNAL, Issue 6 2001Reinskje Talhout Understanding the structural basis of inhibitor,enzyme interactions, important for the design of new drugs, requires a complete thermodynamic characterization of the binding process as well as a description of the structure of the complex. In this paper, the binding of p -substituted benzamidinium derivatives to the structurally well-characterized serine proteinase bovine pancreatic trypsin has been studied using isothermal titration calorimetry. These experiments have permitted a complete characterization of the temperature dependence of the inhibitor-binding thermodynamics. At 25 °C, both the enthalpy and entropy of binding are favourable for all studied derivatives, but this is only true for a relatively narrow temperature range. As binding is characterized by a negative change in heat capacity, the process is characterized by enthalpy,entropy compensation, resulting in a change of the net thermodynamic driving force for association from entropic to enthalpic with increasing temperature. These phenomena are not unusual when hydrophobic forces play an important role. The trend in the relative binding potencies can, to a significant extent, be attributed to the electron-donating/withdrawing character of the substituent at the para position, as shown by the Hammett plot for the different inhibitors; the more polar the p -substituted benzamidine, the less potent it will be as a trypsin inhibitor. This behaviour might result from a bulk solvation effect, meaning that the more polar, lower potency inhibitors will be more stabilized in water than the less polar, higher potency inhibitors. [source] Interpretation of biological activity data of bacterial endotoxins by simple molecular models of mechanism of actionFEBS JOURNAL, Issue 3 2000Vladimir Frecer Lipid A moiety has been identified as the bioactive component of bacterial endotoxins (lipopolysaccharides). However, the molecular mechanism of biological activity of lipid A is still not fully understood. This paper contributes to understanding of the molecular mechanism of action of bacterial endotoxins by comparing molecular modelling results for two possible mechanisms with the underlying experimental data. Mechanisms of action involving specific binding of lipid A to a protein receptor as well as nonspecific intercalation into phospholipid membrane of a host cell were modelled and analysed. As the cellular receptor for endotoxin has not been identified, a model of a peptidic pseudoreceptor was proposed, based on molecular structure, symmetry of the lipid A moiety and the observed character of endotoxin-binding sites in proteins. We have studied the monomeric form of lipid A from Escherichia coli and its seven synthetic analogues with varying numbers of phosphate groups and correlated them with known biological activities determined by the Limulus assay. Gibbs free energies associated with the interaction of lipid A with the pseudoreceptor model and intercalation into phospholipid membrane calculated by molecular mechanics and molecular dynamics methods were used to compare the two possible mechanisms of action. The results suggest that specific binding of lipid A analogues to the peptidic pseudoreceptor carrying an amphipathic cationic binding pattern BHPHB (B, basic; H, hydrophobic; P, polar residue, respectively) is energetically more favourable than intercalation into the phospholipid membrane. In addition, binding affinities of lipid A analogues to the best minimum binding sequence KFSFK of the pseudoreceptor correlated with the experimental Limulus activity parameter. This correlation enabled us to rationalize the observed relationship between the number and position of the phosphate groups in the lipid A moiety and its biological activity in terms of specific ligand,receptor interactions. If lipid A,receptor interaction involves formation of phosphate-ammonium ion-pair(s) with cationic amino-acid residues, the specific mechanism of action was fully consistent with the underlying experimental data. As a consequence, recognition of lipid A variants by an amphipathic binding sequence BHPHB of a host-cell protein receptor might represent the initial and/or rate-determining molecular event of the mechanism of action of lipid A (or endotoxin). The insight into the molecular mechanism of action and the structure of the lipid A-binding pattern have potential implications for rational drug design strategies of endotoxin-neutralizing agents or binding factors. [source] Baltic Sea cyanobacterial bloom contains denitrification and nitrification genes, but has negligible denitrification activityFEMS MICROBIOLOGY ECOLOGY, Issue 2 2003Jaana M Tuomainen Abstract A cyanobacterial bloom in the Gulf of Finland, Baltic Sea, was sampled throughout the development and senescence of aggregates in August 1999. While conditions inside the aggregates were favourable for denitrification (rich in nitrogen and carbon, with anoxic microzones), essentially none was detected by a sensitive isotope pairing method. Polymerase chain reaction-based methods, targeting functional genes encoding the key enzymes of denitrification and nitrification processes (nirS, nirK, amoA), revealed that the non-aggregated filaments harboured amoA gene fragments with high similarity to Nitrosospira amoA sequences, as well as both types of nitrite reductase genes, nirS and nirK. Only the nirS -type nitrite reductase gene and no amoA was detected in aggregated filaments. Thus, despite optimal environmental conditions and genetic potential for denitrification, the blooms of filamentous nitrogen-fixing cyanobacteria must be seen solely as a source, and not as a sink of nitrogen in the Baltic Sea. [source] Snorkelling as a method for assessing spawning stock of Atlantic salmon, Salmo salarFISHERIES MANAGEMENT & ECOLOGY, Issue 3 2007P. ORELL Abstract, Reliability of underwater snorkel counts of adult Atlantic salmon, Salmo salar L., was analysed in the tributaries of the River Teno, close to the spawning period. In small (width 5,20 m) rivers, the replicated total counts of salmon were reasonably precise (CV = 5.4,8.5%), while in the medium-sized river (width 20,40 m) the precision of the counting method was considerably lower (CV = 15.3%). Low precision in a medium sized river was also observed in an experiment using marked live fish where the observation efficiency varied between 36.4% and 70.0%. In a small river, the detection efficiency of artificial fish silhouettes (test salmon) was almost perfect in pools (98%), but decreased in rapids (84%). Separate counts of males, females, grilse and large salmon were usually more variable than total counts, indicating that divers were more capable of locating a fish than properly identifying its sex and sea-age. The behaviour of adult salmon was favourable to conduct snorkel counts, as fish normally stayed still, or after hesitating, moved upstream (>95%of the cases) when encountering a diver. The high observation efficiency (>90%) and precision, favourable behaviour of salmon and congruence between snorkel counts and catch statistics in small rivers suggest that reliable data on Atlantic salmon spawning stock can be collected by snorkeling provided that the environmental conditions are suitable and the divers are experienced. [source] Growth and movement patterns of early juvenile European anchovy (Engraulis encrasicolus L.) in the Bay of Biscay based on otolith microstructure and chemistryFISHERIES OCEANOGRAPHY, Issue 3 2010NAROA ALDANONDO Abstract Various hypotheses have been put forward to explain the mechanisms in the Bay of Biscay that result in a good recruitment of European anchovy. Anchovy larvae from the spawning area in the Gironde River plume are advected towards off-shelf waters, where juveniles are commonly observed. Otolith microstructural and chemical analysis were combined to assess the importance of this off-shelf transport and to determine the relative contribution of these areas for anchovy survival. Chemical analysis of otoliths showed that anchovy juveniles in the Bay of Biscay can be divided into two groups: a group that drifts towards off-shelf waters early in their life and returns later, and a group that remains in the low salinity waters of the coastal area. The first group presents significantly faster growth rates (0.88 mm day,1) than those remaining in the coastal waters (0.32 mm day,1). This may be due to off-shelf waters being warmer in spring/summer, and to the fact that the lower food concentration is compensated for by higher prey visibility. Furthermore, the group of juveniles that drifted off the spawning area and had faster growth rates represents 99% of the juvenile population. These findings support the hypothesis that anchovy in the Bay of Biscay may use off-shelf waters as a spatio-temporal loophole, suggesting that transport off the shelf may be favourable for recruitment. [source] |