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Selected AbstractsThe Ratios of Carbon, Nitrogen, and Phosphorus in a Wetland Coastal Ecosystem of Southern IndiaINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 2 2003Lizen Mathews Abstract The fertility of the coastal and estuarine waters is of great concern because of its influence on the productivity of these waters. Seasonal variations in the distribution of organic carbon, total nitrogen and total phosphorus in the sediments of Kuttanad Waters, a part of the tropical Cochin Estuary on the south west coast of India, are examined to identify the contribution of sediments to the fertility of the aquatic systems. The adjoining region has considerable agricultural activity. The fresh water zones had higher quantities of silt and clay whereas the estuarine zone was more sandy. Organic carbon, total phosphorus and total nitrogen were higher in the fresh water zones and lower in the estuarine zones. Total phosphorus and organic carbon showed the lowest values during monsoon periods. No significant trends were observed in the seasonal distributions of total nitrogen. Ratios of C/N, C/P and N/P, and the phosphorus and nitrogen content indicate significant modification in the character of the organic matter. Substantial amounts of the organic matter can contribute to reducing conditions and modify diagenetic processes. [source] Macrophages transfer [14C]-labelled fatty acids to pancreatic islets in cultureCELL BIOCHEMISTRY AND FUNCTION, Issue 1 2001J. R. Garcia Jr. Abstract Macrophages are able to produce, export, and transfer fatty acids to lymphocytes in culture. The purpose of this study was to examine if labelled fatty acids could be transferred from macrophages to pancreatic islets in co-culture. We found that after 3,h of co-culture the transfer of fatty acids to pancreatic islets was: arachidonic , oleic > linoleic,=,palmitic. Substantial amounts of the transferred fatty acids were found in the phospholipid fraction; 87.6% for arachidonic, 59.9% for oleic, 53.1% for palmitic, and 36.9% for linoleic acids. The remaining radioactivity was distributed among the other lipid fractions analysed (namely polar lipids, cholesterol, fatty acids, triacylglycerol and cholesterol ester), varying with the fatty acid used. For linoleic acid, a significant proportion (63.1%) was almost equally distributed in these lipid fractions. Also, it was observed that transfer of fatty acids from macrophages to pancreatic islets is time-dependent up to 24,h, being constant and linear with time for palmitic acid and remaining constant after 12,h for oleic acid. These results lead us to postulate that in addition to the serum, circulating monocytes may also be a source of fatty acids to pancreatic islets, mainly arachidonic acid. Copyright © 2001 John Wiley & Sons, Ltd. [source] Examining the role of the forest industry in collaborative ecosystem management: implications for corporate strategyCORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 1 2005Jennifer Dyke Abstract The North American timber industry owns or controls a substantial amount of commercial timberland, and it is within this privately held acreage that major portions of critical natural habitat and areas of biodiversity are found. Because significant ecosystem components and processes lie within the ownership of forestry operations, industry participation in collaborative ecosystem management initiatives is vital to protect the integrity of ecological units at the landscape scale. This article analyzes and identifies the role of industry in ecosystem management projects, industry's willingness to participate in collaborative ecosystem management and the motivations behind company participation. Companies indicated active involvement in collaborative ecosystem management as both project initiators and collaborators. Motivations for participating in collaborative ecosystem management initiatives include the desires to decrease governmental regulations, collect data, develop relationships and improve current practices. Many companies also feel that participation is financially beneficial because it positively impacts corporate public relations. We discuss the implications of these results for developing an effective corporate environmental strategy associated with resource-based industries. Copyright © 2005 John Wiley & Sons, Ltd and ERP Environment. [source] Name change among offender patients: an English high security hospital sampleCRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 4 2002Birgit Völlm Clinical Research Fellow Background There is scant literature on change of name among psychiatric patients but a more substantial amount on the use of aliases among offenders. No one to our knowledge has explored name changes among offender patients. Aim This study was undertaken to establish the prevalence of name change among high security hospital patients and to compare those who changed name with those who did not. Hypothesis It was hypothesized that name change would be associated with male gender, repeated offending and a diagnosis of personality disorder. Method The clinical records of all patients resident in one high security hospital on 31 January 2000 were searched. As all such patients are compulsorily detained, all name changes must be recorded. Any change prior to that date was also noted, together with basic demographic and diagnostic information; supplementary data were obtained from the special hospitals' case register. Results Seventy-one patients (17%) of the resident population changed names (exclusive of a woman changing her surname on marriage). Name changing was associated with disrupted upbringing. Patients with personality disorder were more likely to change names than those with psychosis, regardless of sex, age or ethnic group. Those with psychosis were more likely to select unusual or symbolic names. Conclusions On the evidence of previous literature, people from this serious offender patient population were more likely to change names than other psychiatric patients but less likely than non-mentally-disordered offenders. Changes by people with psychosis seemed related to their illness, whereas changes by those with personality disorder might reflect childhood disruptions in rearing patterns. Copyright © 2002 Whurr Publishers Ltd. [source] Recovery of flagellar dynein function in a Chlamydomonas actin/dynein-deficient mutant upon introduction of muscle actin by electroporationCYTOSKELETON, Issue 3 2001Masahito Hayashi Abstract Flagellar and ciliary inner-arm dyneins contain actin as a subunit; however, the function of this actin subunit remains unknown. As a first step toward experimental manipulation of actin in dynein, we developed a method for introducing exogenous actin into Chlamydomonas cells by electroporation. A non-motile mutant, ida5oda1, lacking inner-arm dyneins due to the absence of conventional actin, was electroporated in the presence of rabbit skeletal muscle actin. About 20% of the electroporated cells recovered motility under optimal conditions. In addition, by taking advantage of their phototactic behavior, the rescued cells could be concentrated. Motility was also recovered with fluorescently labeled actin; in this case, axonemes became fluorescent after electroporation, suggesting that actin was in fact incorporated as a dynein subunit. The feasibility of incorporating a substantial amount of macromolecules by electroporation will be useful not only for studying actin function, but also for a variety of studies using Chlamydomonas in which no efficient methods have been developed for expressing or introducing foreign proteins and other macromolecules. Cell Motil. Cytoskeleton 49:146,153, 2001. © 2001 Wiley-Liss, Inc. [source] The mechanism of Drosophila leg development along the proximodistal axisDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 2 2004Tetsuya Kojima During development of higher organisms, most patterning events occur in growing tissues. Thus, unraveling the mechanism of how growing tissues are patterned into final morphologies has been an essential subject of developmental biology. Limb or appendage development in both vertebrates and invertebrates has attracted great attention from many researchers for a long time, because they involve almost all developmental processes required for tissue patterning, such as generation of the positional information by morphogen, subdivision of the tissue into distinct parts according to the positional information, localized cell growth and proliferation, and control of adhesivity, movement and shape changes of cells. The Drosophila leg development is a good model system, upon which a substantial amount of knowledge has been accumulated. In this review, the current understanding of the mechanism of Drosophila leg development is described. [source] Detection of microbial biomass by intact polar membrane lipid analysis in the water column and surface sediments of the Black SeaENVIRONMENTAL MICROBIOLOGY, Issue 10 2009Florence Schubotz Summary The stratified water column of the Black Sea produces a vertical succession of redox zones, stimulating microbial activity at the interfaces. Our study of intact polar membrane lipids (IPLs) in suspended particulate matter and sediments highlights their potential as biomarkers for assessing the taxonomic composition of live microbial biomass. Intact polar membrane lipids in oxic waters above the chemocline represent contributions of bacterial and eukaryotic photosynthetic algae, while anoxygenic phototrophic bacteria and sulfate-reducing bacteria comprise a substantial amount of microbial biomass in deeper suboxic and anoxic layers. Intact polar membrane lipids such as betaine lipids and glycosidic ceramides suggest unspecified anaerobic bacteria in the anoxic zone. Distributions of polar head groups and core lipids show planktonic archaea below the oxic zone; methanotrophic archaea are only a minor fraction of archaeal biomass in the anoxic zone, contrasting previous observations based on the apolar derivatives of archaeal lipids. Sediments contain algal and bacterial IPLs from the water column, but transport to the sediment is selective; bacterial and archaeal IPLs are also produced within the sediments. Intact polar membrane lipid distributions in the Black Sea are stratified in accordance with geochemical profiles and provide information on vertical successions of major microbial groups contributing to suspended biomass. This study vastly extends our knowledge of the distribution of complex microbial lipids in the ocean. [source] Seasonal dynamics of the hepatotoxic microcystins in various organs of four freshwater bivalves from the large eutrophic lake Taihu of subtropical China and the risk to human consumptionENVIRONMENTAL TOXICOLOGY, Issue 6 2005Jun Chen Abstract So far, little is known on the distribution of hepatotoxic microcystin (MC) in various organs of bivalves, and there is no study on MC accumulation in bivalves from Chinese waters. Distribution pattern and seasonal dynamics of MC-LR, -YR and -RR in various organs (hepatopancreas, intestine, visceral mass, gill, foot, and rest) of four edible freshwater mussels (Anodonta woodiana, Hyriopsis cumingii, Cristaria plicata, and Lamprotula leai) were studied monthly during Oct. 2003,Sep. 2004 in Lake Taihu with toxic cyanobacterial blooms in the summer. Qualitative and quantitative determinations of MCs in the organs were done by LC,MS and HPLC. The major toxins were present in the hepatopancreas (45.5,55.4%), followed by visceral mass with substantial amount of gonad (27.6,35.5%), whereas gill and foot were the least (1.8,5.1%). The maximum MC contents in the hepatopancreas, intestine, visceral mass, gill, foot, and rest were 38.48, 20.65, 1.70, 0.64, 0.58, and 0.61 ,g/g DW, respectively. There were rather good positive correlation in MC contents between intestines and hepatopancreas of the four bivalves (r = 0.75,0.97, p < 0.05). There appeared to be positive correlations between the maximum MC content in the hepatopancreas and the ,13C (r = 0.919) or ,15N (r = 0.878) of the foot, indicating that the different MC content in the hepatopancreas might be due to different food ingestion. A glutathione (GSH) conjugate of MC-LR was also detected in the foot sample of C. plicata. Among the foot samples analyzed, 54% were above the provisional WHO tolerable daily intake (TDI) level, and the mean daily intakes from the four bivalves were 8,23.5 times the TDI value when the bivalves are eaten as a whole, suggesting the high risk of consuming bivalves in Lake Taihu. © 2005 Wiley Periodicals, Inc. Environ Toxicol 20: 572,584, 2005. [source] Temperature-Resolved Local and Macroscopic Charge Carrier Transport in Thin P3HT Layers,ADVANCED FUNCTIONAL MATERIALS, Issue 14 2010Patrick Pingel Abstract Previous investigations of the field-effect mobility in poly(3-hexylthiophene) (P3HT) layers revealed a strong dependence on molecular weight (MW), which was shown to be closely related to layer morphology. Here, charge carrier mobilities of two P3HT MW fractions (medium-MW: Mn,=,7,200 g mol,1; high-MW: Mn,=,27,000 g mol,1) are probed as a function of temperature at a local and a macroscopic length scale, using pulse-radiolysis time-resolved microwave conductivity (PR-TRMC) and organic field-effect transistor measurements, respectively. In contrast to the macroscopic transport properties, the local intra-grain mobility depends only weakly on MW (being in the order of 10,2 cm2 V,1 s,1) and being thermally activated below the melting temperature for both fractions. The striking differences of charge transport at both length scales are related to the heterogeneity of the layer morphology. The quantitative analysis of temperature-dependent UV/Vis absorption spectra according to a model of F. C. Spano reveals that a substantial amount of disordered material is present in these P3HT layers. Moreover, the analysis predicts that aggregates in medium-MW P3HT undergo a "pre-melting" significantly below the actual melting temperature. The results suggest that macroscopic charge transport in samples of short-chain P3HT is strongly inhibited by the presence of disordered domains, while in high-MW P3HT the low-mobility disordered zones are bridged via inter-crystalline molecular connections. [source] The relative importance of local conditions and regional processes in structuring aquatic plant communitiesFRESHWATER BIOLOGY, Issue 5 2010ROBERT S. CAPERS Summary 1. The structure of biological communities reflects the influence of both local environmental conditions and processes such as dispersal that create patterns in species' distribution across a region. 2. We extend explicit tests of the relative importance of local environmental conditions and regional spatial processes to aquatic plants, a group traditionally thought to be little limited by dispersal. We used partial canonical correspondence analysis and partial Mantel tests to analyse data from 98 lakes and ponds across Connecticut (northeastern United States). 3. We found that aquatic plant community structure reflects the influence of local conditions (pH, conductivity, water clarity, lake area, maximum depth) as well as regional processes. 4. Only 27% of variation in a presence/absence matrix was explained by environmental conditions and spatial processes such as dispersal. Of the total explained, 45% was related to environmental conditions and 40% to spatial processes. 5. Jaccard similarity declined with Euclidean distance between lakes, even after accounting for the increasing difference in environmental conditions, suggesting that dispersal limitation may influence community composition in the region. 6. The distribution of distances among lakes where species occurred was associated with dispersal-related functional traits, providing additional evidence that dispersal ability varies among species in ways that affect community composition. 7. Although environmental and spatial variables explained a significant amount of variation in community structure, a substantial amount of stochasticity also affects these communities, probably associated with unpredictable colonisation and persistence of the plants. [source] Retention of chloride in soil and cycling of organic matter-bound chlorineHYDROLOGICAL PROCESSES, Issue 11 2005G. Öberg Abstract Chloride (Clinorg) is generally considered to be a hydrologically and chemically inert substance. Past research suggests that Clinorg participates in a complex biogeochemical cycle involving the formation of organically bound chlorine (Clorg). The present study examines whether Clorg cycling is sufficiently extensive as to influence the geochemical cycling of Clinorg. Undisturbed soil cores were collected in a coniferous forest soil in SE Sweden. The cores were stored in climate chambers for three months, irrigated with artificial rain, and the leachate was collected and analysed. The water balance of the lysimeters could be well described, and we found that 20,50% of the chlorine leached from the lysimeters was organically bound and that the amounts lost did not decrease with time. This strongly suggests that a substantial amount of Clorg forms in topsoil, and that subsequent leaching to deeper layers causes a considerable withdrawal of Clinorg. The concentration of both organic carbon and Clorg in the leachate was considerably higher than concentrations observed in the runoff in the actual catchment, suggesting that organic matter precipitates or is mineralized on its way through the soil. Copyright © 2005 John Wiley & Sons, Ltd. [source] Inter-relations between experimental and computational aspects of slope stability analysisINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 5 2003R. Baker Abstract Most conventional slope stability calculations are based on the linear Mohr,Coulomb failure criterion. However, a substantial amount of experimental evidence suggests that failure criteria of many soils are not linear particularly in the range of small normal stresses. This departure from linearity is significant for slope stability calculations since for a wide range of practical stability problems, critical slip surfaces are shallow and normal stresses acting on such surfaces are small. There exists a technical difficulty in performing strength measurements in the range of small normal stresses relevant to such slope stability problems. As a result, in many practical situations strength measurements are performed at much larger normal stresses then those relevant for the stability problem under consideration. When this is the case, use of the Mohr,Coulomb criterion amounts to a linear extrapolation of experimental information (obtained at large normal stresses), into the range of small normal stresses, which is relevant to the problem. This extrapolation results with very significant overestimation of calculated safety factors in cases when there is large mismatch between experimental and relevant ranges of normal stresses. The present work delineates the extent of this problem and suggests a practical way to overcome it. Copyright © 2003 John Wiley & Sons, Ltd. [source] Effect of lactic acid fermentation of onions (Allium cepa) on the composition of flavonol glucosidesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 7 2007Barbara Bisakowski Summary Fermentation of red onions inoculated with Lactobacillus plantarum S1 (starter treatment) resulted in acid production to pH 4.5, after 48 h of incubation at 19 °C, which has proven to be adequate for proper preservation. In the presence of erythromycin (starter + antibiotic), acidification to pH 5.2 resulted, which was similar to that of the uninoculated control. The bacterial population was about 108 CFU mL,1 of brine after 3 days for the three treatments, suggesting that in the starter + antibiotic treatment, the antibiotic effectively suppressed the activity of the starter but not the native flora. Before lactic fermentation, the red onions contained 297.4 mg of total quercetin (Q) per kg wet weight, which consisted of 58.3%, 41.6% and 0.1% in quercetin diglucoside (Qdg), quercetin monoglucoside (Qmg) and free Q, respectively. For the starter treatment, Qdg decreased to 41.8% and 18.3% at 48 and 72 h, respectively, and a substantial amount of free Q had accumulated. The fermentation substantially increased the proportion of Qmg, which may have a positive effect as fractions containing higher ratios of Qmg to Qdg have been reported to have higher antioxidant activity. [source] Conjunctive water management options: examples from economic assessment of system-level water saving through Liuyuankou Irrigation System, China,IRRIGATION AND DRAINAGE, Issue 5 2007Shahbaz Khan économies d'eau à l'échelle d'un périmètre; modèle dynamique d'un système d'irrigation; fonctions de production et de profit; Chine Abstract The paper provides results of a study aimed at saving a substantial amount of water by maintaining deeper groundwater levels to prevent fallow evaporation and by reducing the cost of groundwater abstraction for lowland farmers. An integrated LIS economic appraisal model was developed that linked simulated response of hydrological modelling of different conjunctive management options with economic analysis. The simulation results of the LIS system dynamic model show that a combination of canal lining and pumping groundwater is the most cost-effective way to reduce non-beneficial evapotranspiration and increase water availability by saving up to 68 MCM of water. The simulation results of economic parameters indicated that canal lining and pumping also offer highest net economic benefits (¥21.98 million). Among other options, canal lining also indicates reasonably high net economic benefits (¥9.02 million). The model indicates a small increase in marginal value of water with canal lining (¥1.53,m,3) and pumping and canal lining (¥1.62,m,3). Among other options, the marginal capital cost of water saving for pumping and canal lining together was the lowest (¥0.096,m,3). However, the marginal capital cost of water saving for pumping and shifting canal water downstream was the most expensive (¥1.046,m,3). Copyright © 2007 John Wiley & Sons, Ltd. L'article présente les résultats d'une étude destinée à économiser des quantités d'eau substantielles en maintenant le niveau des nappes suffisamment bas pour éviter l'évaporation non bénéficiaire et en réduisant le coût des prélèvements d'eau souterraine pour les irrigants des parties basses du périmètre. Le modèle d'évaluation économique intégrée LIS (Liuyuankou Irrigation System) a été développé en reliant les réponses simulées de modélisation hydrologique de différentes options de gestion mixte à l'analyse économique. Les résultats des simulations du modèle LIS montrent que la combinaison du revêtement des canaux et du pompage d'eau souterraine est le moyen le plus efficient de réduire l'évapotranspiration non bénéficiaire et d'augmenter la disponibilité de l'eau en économisant jusqu'à 68 Mm3. Les simulations économiques indiquent que le revêtement des canaux et le pompage procurent les bénéfices économiques nets les plus élevés (21,98 millions de ¥). Parmi les autres options, le revêtement des canaux seul procure lui aussi des bénéfices économiques nets relativement élevés (9,02 millions de ¥). Le modèle indique une légère augmentation de l'utilité marginale de l'eau en cas de canaux revêtus (1,53 ¥ m,3) et en cas de combinaison revêtement + pompage (1,62 ¥ m,3). Parmi les autres options, le coût marginal d'économie de l'eau pour la même combinaison était le plus bas (0,096 ¥ m,3). Cependant, le coût marginal d'économie d'eau pour pompage et transfert vers l'aval était le plus coûteux (1,046 ¥ m,3). Copyright © 2007 John Wiley & Sons, Ltd. [source] A Single EU Seat in the IMF?JCMS: JOURNAL OF COMMON MARKET STUDIES, Issue 2 2004Lorenzo Bini Smaghi This article examines the rationale for consolidating EU Member States' position in the International Monetary Fund (IMF). Although a substantial amount of co-ordination already takes place, particularly on issues related to the euro area and the single monetary and exchange rate policy, co-operation between EU countries in the IMF remains a relatively new phenomenon and divergences still prevail. The current institutional set-up, whereby the 15 EU countries are spread in nine constituencies, undermines effectiveness. Al though there is scope for further improving co-operation, there are natural limits to what can be achieved within the existing co-operation frame work. A single EU constituency would enable EU Member States to have a strong impact on IMF policies, potentially as strong as that of the US. However, this may not be an objective for all EU countries in the current conjuncture. [source] Interfacing biocatalysis and organic synthesis,JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 12 2007Roland Wohlgemuth Abstract The path to new chemical entities often shows the limitations of existing tools both in biocatalysis and organic chemistry. Organic synthetic procedures to prepare a compound in a target-oriented synthesis can damage other functional parts of the molecule. Protection,deprotection schemes can lead to a dead end, when a certain protecting group cannot be cleaved off. In biocatalysis, on the other hand, the required biocatalytic toolbox and methodology might not be readily available, therefore limiting a biocatalytic approach. New toolboxes, ingredients, and methodologies at the interface of classical organic synthesis and biocatalytic reactions bridge the gap between these two areas. Since product isolation and purification involves a substantial amount of time in the preparation of chemicals, methodologies to simplify these tasks are necessary to get the pure product into the bottle with less work-up time. Efficient and safe new pharmaceuticals, intermediates and analytical reagents need to be prepared under certain safety, health, environmental and economical boundary conditions. Biocatalytic reactions have been shown to overcome these limitations successfully and are becoming increasingly important in industrial manufacturing. Building bridges between biocatalysis and organic synthesis will therefore create roads to new synthetic strategies and technological frontiers of both fundamental and practical interest. Copyright © 2007 Society of Chemical Industry [source] Measuring the Benefits of Examinee-Selected QuestionsJOURNAL OF EDUCATIONAL MEASUREMENT, Issue 1 2005Nancy L. Allen Allowing students to choose the question(s) that they will answer from among several possible alternatives is often viewed as a mechanism for increasing fairness in certain types of assessments. The fairness of optional topic choice is not a universally accepted fact, however, and various studies have been done to assess this question. We examine an important class of experiments that we call C1-A, "choose one, answer all," designs, and point out an important problem that they face. We suggest two analytical methods that can be used to circumvent this problem. We illustrate our ideas using the data from Bridgeman et al. (1997). Our reanalysis of these data show: (a) that differential topic difficulty exists in real choice data, (b) that it affects naïve analyses of such data and masks the effects, positive or negative, of examinee choice, (c) that in this study there is a measurable and positive effect of examinee choice that follows predicted patterns in most but not all cases, (d) that the beneficial strength of examinee choice varies from case to case, and (e) that while the benefits of choice in terms of average points scored on the essays are usually positive, there is a substantial amount of variation around these averages and it is not uncommon for "incorrect" choices to be associated with higher test performance. [source] Condition-dependent traits and the capture of genetic variance in male advertisement songJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 4 2004L. S. E. Brandt Abstract The occurrence of additive genetic variance (VA) for male sexual traits remains a major problem in evolutionary biology. Directional selection normally imposed by female choice is expected to reduce VA greatly, yet recent surveys indicate that a substantial amount remains in many species. We addressed this problem, also known as the ,lek paradox', in Achroia grisella (Lepidoptera: Pyralidae), an acoustic moth in which males advertise to females with a pulsed ultrasonic song. Using a standard half-sib/full-sib breeding design, we generated F1 progeny from whom we determined VA and genetic covariance (COVA) among seven traits: three song characters, an overall index of song attractiveness, nightly singing period, adult lifespan, and body mass at adult eclosion. Because A. grisella neither feed nor drink as adults, the last trait, eclosion body mass, is considered a measure of ,condition'. We found significant levels of VA and narrow-sense heritabilities (h2) for all seven traits and significant genetic correlations (= COVAi,j /,(VA i·VA j)) between most pairs of traits (i, j). Male attractiveness was positively correlated with body mass (condition), adult lifespan, and nightly singing period, which we interpret as an energy constraint preventing males in poor condition from singing attractively, from singing many hours per night, and from surviving an extended lifespan. The positive genetic correlation (r = 0.79) between condition and attractiveness, combined with significant levels of VA for both traits, indicates that much of the variation in male song can be explained by VA for condition. Finally, we discuss the morphological and physiological links between condition and song attractiveness, and the ultimate factors that may maintain VA for condition. [source] ROLE OF SATURATED FATTY ACIDS IN LIPASE PRODUCTION , USING PSEUDOMONAS AERUGINOSAJOURNAL OF FOOD BIOCHEMISTRY, Issue 6 2007A.N. SARAVANAN ABSTRACT Complex substrates always induce substantial amount of enzyme production during hydrolysis by microorganisms. In this study, ghee was taken for its saturated fatty acid content and analyzed as an inducer for the production of lipase. With ghee emulsion, the bacterium Pseudomonas aeruginosa at optimal condition produced 60 units/min/L at 72 h. With olive oil emulsion, this organism produced only 41 units/min/L as maximum at 96 h. The saturated fatty acids present in ghee make it a hard substance for hydrolysis, which is the reason for the increased enzyme production. This was evaluated by the iodine number experiment. Ghee can also reduce the production cost whereas the costlier olive oil constitutes 25,50% of the total production cost for a commercial scale. The experimental results showed that the saturated fatty acids play an important role in lipase enzyme induction by P. aeruginosa. The use of ghee is cost-effective; hence, it can be used as a potential inducer for lipase production. PRACTICAL APPLICATIONS Lipases are industrially very important enzymes. They are used in pharmaceutical, food, soap and other industries. In lipase production, olive oil is the main constituent. Comparatively, olive oil is costlier; hence, it increases the production cost of lipase. So, this study was done to replace olive oil with a much cheaper ghee using Pseudomonas aeruginosa. The ghee-containing medium gave a very good result because of the presence of complex saturated fatty acids. The ghee-containing medium produced 60 units/min/L at 72 h. The olive oil medium, which contains mainly unsaturated fatty acids, produced only 41 units/min/L as maximum at 96 h. Hence, in the commercial scale, ghee can reduce raw material cost as well as operation time cost significantly when it is used as substrate. [source] Effects of genotype, elevated CO2 and elevated O3 on aspen phytochemistry and aspen leaf beetle Chrysomela crotchi performanceAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2010Leanne M. Vigue 1Trembling aspen Populus tremuloides Michaux is an important forest species in the Great Lakes region and displays tremendous genetic variation in foliar chemistry. Elevated carbon dioxide (CO2) and ozone (O3) may also influence phytochemistry and thereby alter the performance of insect herbivores such as the aspen leaf beetle Chrysomela crotchi Brown. 2The present study aimed to relate genetic- and atmospheric-based variation in aspen phytochemistry to C. crotchi performance (larval development time, adult mass, survivorship). The experiment was conducted at the Aspen Free-Air CO2 Enrichment (FACE) site in northern Wisconsin. Beetles were reared on three aspen genotypes under elevated CO2 and/or O3. Leaves were collected to determine chemical characteristics. 3The foliage exhibited significant variation in nitrogen, condensed tannins and phenolic glycosides among genotypes. CO2 and O3, however, had little effect on phytochemistry. Nonetheless, elevated CO2 decreased beetle performance on one aspen genotype and had inconsistent effects on beetles reared on two other genotypes. Elevated O3 decreased beetle performance, especially for beetles reared on an O3 -sensitive genotype. Regression analyses indicated that phenolic glycosides and nitrogen explain a substantial amount (27,45%) of the variation in herbivore performance. 4By contrast to the negative effects that are typically observed with generalist herbivores, aspen leaf beetles appear to benefit from phenolic glycosides, chemical components that are largely genetically-determined in aspen. The results obtained in the present study indicate that host genetic variation and atmospheric concentrations of greenhouse gases will be important factors in the performance of specialist herbivores, such as C. crotchi, in future climates. [source] Genes, gene flow and adaptation of Diabrotica virgifera virgiferaAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 1 2009Nicholas J. Miller Abstract 1,Diabrotica virgifera virgifera has emerged as a major pest of cultivated maize, due to a combination of its high capacity to inflict economic damage, adaptability to pest management techniques and invasiveness. 2,This review presents a survey of the current state of knowledge about the genetics of D. v. virgifera. In addition, the tools and resources currently available to Diabrotica geneticists are identified, as are areas where knowledge is lacking and research should be prioritized. 3,A substantial amount of information has been published concerning the molecular phylogenetic relationships of D. v. virgifera to other chrysomelids. 4,There is a growing literature focused on the population genetics and evolution of the species. Several adaptations to anthropogenic selection pressure have been studied, with resistance to synthetic insecticides providing some particularly well-characterized examples. 5,A notable deficiency is a lack of studies directed toward the formal genetics of D. v. virgifera. [source] Petrogenetic modelling of strongly residual metapelitic xenoliths within the southern Platreef, Bushveld Complex, South AfricaJOURNAL OF METAMORPHIC GEOLOGY, Issue 3 2010T. E. JOHNSON Abstract Xenoliths of quartz-absent Fe-rich aluminous metapelite are common within the platinum group element-rich mafic/ultramafic magmatic rocks of the Platreef. Relative to well-characterized protoliths, the xenoliths are strongly depleted in K2O and H2O, and have lost a substantial amount of melt (>50 vol.%). Mineral equilibria calculations in the NCKFMASHTO system yield results that are consistent with observations in natural samples. Lower-grade rocks that lack staurolite constrain peak pressures to ,2.5 kbar in the southern Platreef. Smaller xenoliths and the margins of larger xenoliths comprise micro-diatexite rich in coarse acicular corundum and spinel, which record evidence for the metastable persistence of lower-grade hydrous phases and rapid melting consequent on a temperature overstep of several hundred degrees following their incorporation in the mafic/ultramafic magmas. In the cores of larger xenoliths, temperatures increased more slowly enabling progressive metamorphism by continuous prograde equilibration and the loss of H2O by subsolidus dehydration; the H2O migrated to xenolith margins where it may have promoted increased melting. According to variations in the original compositional layering, layers became aluminosilicate- and/or cordierite-rich, commonly with spinel but only rarely with corundum. The differing mineralogical and microstructural evolution of the xenoliths depends on heating rates (governed by their size and, therefore, proximity to the Platreef magmas) and the pre-intrusive metamorphic grade of the protoliths. The presence or absence of certain phases, particularly corundum, is strongly influenced by the degree of metastable retention of lower-grade hydrates in otherwise identical protolith bulk compositions. The preservation of fine-scale compositional layering that is inferred to be relict bedding in xenolith cores implies that melt loss by compaction was extremely efficient. [source] Leisure-Time Physical Activity in Elementary Schools: Analysis of Contextual ConditionsJOURNAL OF SCHOOL HEALTH, Issue 10 2010Thomas L. McKenzie PHD BACKGROUND: Little is known about children's leisure-time physical activity (PA) at school and how it is associated with contextual variables. The purpose of this study was to objectively assess children's voluntary PA during 3 daily periods and examine modifiable contextual factors. METHODS: We conducted SOPLAY (System for Observing Play and Leisure Activity in Youth) observations before school, during recess, and at lunchtime in 137 targeted activity areas in 13 elementary schools over 18 months. During observations, each child was coded as Sedentary, Walking, or Vigorous, and simultaneous entries were made for area characteristics (accessibility, usability, presence of supervision, loose equipment, and organized activities). Logistic regression analysis was used to test associations between PA and area characteristics. RESULTS: Assessors made 2349 area visits and observed 36,995 children. Boys had more moderate-to-vigorous physical activity (MVPA; 66.2 vs 60.0%, p < .001) and more vigorous PA (29.8 vs 24.6%; p < .001) than girls. Areas were typically accessible and usable, but provided organized activities infrequently (16.5%). Odds of engaging in MVPA were greater during lunch and recess than before school and in areas with play equipment (p < .05). CONCLUSIONS: Children accrued a substantial amount of voluntary PA during leisure time at school. Their PA would likely be increased if school playground equipment was more readily available and if supervisors were taught to provide active games and promote PA rather than suppress it. [source] Dispersion Behavior of ZrB2 Powder in Aqueous SolutionJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 11 2007Sea-Hoon Lee Dispersion conditions of ZrB2 powder in water were investigated using poly(ethyleneimine) (PEI) as a dispersant. Pulverization of ZrB2 powder to submicrometer size was difficult and a substantial amount of large particles remained after an intensive planatery milling for 72 h. The isoelectric point (IEP) of ZrB2 powder was measured to be pH 5.8 by electrophoresis, which shifted to pH 6.2 after milling. The application of PEI changed the IEP of the boride slurry to ,pH 11. Well-dispersed aqueous ZrB2 slurries with a high solid loading (up to 45 vol%) were fabricated at pH 6.5,7.5 by the application of 1.5 wt% PEI. [source] Foliar demand and resource economy of nutrients in dry tropical forest speciesJOURNAL OF VEGETATION SCIENCE, Issue 1 2001C.B. Lal Important phenological activities in seasonally dry tropical forest species occur within the hot-dry period when soil water is limiting, while the subsequent wet period is utilized for carbon accumulation. Leaf emergence and leaf area expansion in most of these tree species precedes the rainy season when the weather is very dry and hot and the soil cannot support nutrient uptake by the plants. The nutrient requirement for leaf expansion during the dry summer period, however, is substantial in these species. We tested the hypothesis that the nutrients withdrawn from the senescing leaves support the emergence and expansion of leaves in dry tropical woody species to a significant extent. We examined the leaf traits (with parameters such as leaf life span, leaf nutrient content and retranslocation of nutrients during senescence) in eight selected tree species in northern India. The concentrations of N, P and K declined in the senescing foliage while those of Na and Ca increased. Time series observations on foliar nutrients indicated a substantial amount of nutrient resorption before senescence and a ,tight nutrient budgeting'. The resorbed N-mass could potentially support 50 to 100% and 46 to 80% of the leaf growth in terms of area and weight, respectively, across the eight species studied. Corresponding values for P were 29 to 100% and 20 to 91%, for K 29 to 100% and 20 to 57%, for Na 3 to 100% and 1 to 54%, and for Ca 0 to 32% and 0 to 30%. The species differed significantly with respect to their efficiency in nutrient resorption. Such interspecific differences in leaf nutrient economy enhance the conservative utilization of soil nutrients by the dry forest community. This reflects an adaptational strategy of the species growing on seasonally dry, nutrient-poor soils as they tend to depend more or less on efficient internal cycling and, thus, utilize the retranslocated nutrients for the production of new foliage biomass in summer when the availability of soil moisture and nutrients is severely limited. [source] The impact of case specificity and generalisable skills on clinical performance: a correlated traits,correlated methods approachMEDICAL EDUCATION, Issue 6 2008Paul F Wimmers Context, The finding of case or content specificity in medical problem solving moved the focus of research away from generalisable skills towards the importance of content knowledge. However, controversy about the content dependency of clinical performance and the generalisability of skills remains. Objectives, This study aimed to explore the relative impact of both perspectives (case specificity and generalisable skills) on different components (history taking, physical examination, communication) of clinical performance within and across cases. Methods, Data from a clinical performance examination (CPX) taken by 350 Year 3 students were used in a correlated traits,correlated methods (CTCM) approach using confirmatory factor analysis, whereby ,traits' refers to generalisable skills and ,methods' to individual cases. The baseline CTCM model was analysed and compared with four nested models using structural equation modelling techniques. The CPX consisted of three skills components and five cases. Results, Comparison of the four different models with the least-restricted baseline CTCM model revealed that a model with uncorrelated generalisable skills factors and correlated case-specific knowledge factors represented the data best. The generalisable processes found in history taking, physical examination and communication were responsible for half the explained variance, in comparison with the variance related to case specificity. Conclusions, Pure knowledge-based and pure skill-based perspectives on clinical performance both seem too one-dimensional and new evidence supports the idea that a substantial amount of variance contributes to both aspects of performance. It could be concluded that generalisable skills and specialised knowledge go hand in hand: both are essential aspects of clinical performance. [source] From cells to tissues: Fluorescence confocal microscopy in the study of histological samplesMICROSCOPY RESEARCH AND TECHNIQUE, Issue 2 2004Pietro Transidico Abstract Our knowledge of the genetic mechanisms controlling cell proliferation and differentiation usually originates from in vitro cultured cell line models. However, the definition of the molecular switches involved in control of homeostasis and the understanding of the changes occurring in neoplastic transformation require looking at single cells as the components of a complex tissue network. Histological examination of tissue samples can gain a substantial amount of information from high-resolution fluorescence analysis. In particular, confocal microscopy can help in the definition of functional pathways using multiparameter analysis. In this report, we present acquisition and analysis procedures to obtain high-resolution data from tissue sections. Confocal microscopy coupled to computational restoration, statistical evaluation of spatial correlations, and morphological analysis over large tissue areas were applied to colorectal samples providing a molecular fingerprint of the biological differences inferred from classical histological examination. Microsc. Res. Tech. 64:89,95, 2004. © 2004 Wiley-Liss, Inc. [source] Computability of compact operators on computable Banach spaces with basesMLQ- MATHEMATICAL LOGIC QUARTERLY, Issue 4-5 2007Vasco Brattka Abstract We develop some parts of the theory of compact operators from the point of view of computable analysis. While computable compact operators on Hilbert spaces are easy to understand, it turns out that these operators on Banach spaces are harder to handle. Classically, the theory of compact operators on Banach spaces is developed with the help of the non-constructive tool of sequential compactness. We demonstrate that a substantial amount of this theory can be developed computably on Banach spaces with computable Schauder bases that are well-behaved. The conditions imposed on the bases are such that they generalize the Hilbert space case. In particular, we prove that the space of compact operators on Banach spaces with monotone, computably shrinking, and computable bases is a computable Banach space itself and operations such as composition with bounded linear operators from left are computable. Moreover, we provide a computable version of the Theorem of Schauder on adjoints in this framework and we discuss a non-uniform result on composition with bounded linear operators from right. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Divine Unity and the Divided Self: Gregory of Nyssa's Trinitarian Theology in its Psychological ContextMODERN THEOLOGY, Issue 4 2002Michel René Barnes In the last hundred years Gregory of Nyssa's Trinitarian theology has received a substantial amount of attention. Unfortunately, it has been appropriated because of its perceived psychological content,so much so that Gregory's Trinitarian theology becomes re,stated as the Trinity as "personal relationship" or as "locating consciousness(es) in the Trinity." To be sure, a knowledge of Gregory's psychology reveals its role in his Trinitarian theology; however, it also makes clear that personal relationship or consciousness are not important, substantial psychological concepts in the way that they are often taken to be by contemporary interpreters. Rather, Gregory's psychology takes its fundamental shape from a concern for the integrity of the will in its action. [source] Constraints on the merging time-scale of luminous red galaxies, or, where do all the haloes go?MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2007Charlie Conroy ABSTRACT In the , cold dark matter cosmology, dark matter haloes grow primarily through the accretion of smaller haloes. Much of the mass in a halo of 1014 M, comes in through accretion of ,1013 M, haloes. If each such halo hosted one luminous red galaxy (LRG) then the accretion of so many haloes is at odds with the observed number of LRGs in clusters unless these accreted LRGs merge or disrupt on relatively short time-scales (,2 Gyr). These time-scales are consistent with classical dynamical friction arguments, and imply that two to three LRGs have merged or disrupted within each halo more massive than 1014 M, by z= 0. The total amount of stellar mass brought into these massive haloes by z= 0 is consistent with observations once the intracluster light (ICL) is included. If disrupted LRGs build up the ICL, then the hierarchical growth of massive haloes implies that a substantial amount of ICL should also surround satellite LRGs, as suggested by recent observations of the Virgo cluster. Finally, we point out that these results are entirely consistent with a non-evolving clustering strength and halo occupation distribution, and note that observations of the latter in fact support the hypothesis that merging/disruption of massive galaxies does indeed take place at late times. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||