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Large Differences (large + difference)
Selected AbstractsComparative sediment quality guideline performance for predicting sediment toxicity in Southern California, USAENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2005Doris E. Vidal Abstract Several types of sediment quality guidelines (SQGs) are used by multiple agencies in southern California (USA) to interpret sediment chemistry data, yet little information is available to identify the best approaches to use. The objective of this study was to evaluate the predictive ability of five SQGs to predict the presence and absence of sediment toxicity in coastal southern California: the effects range-median quotient (ERMq), consensus moderate effect concentration (consensus MEC), mean sediment quality guideline quotient (SQGQ1), apparent effects threshold (AET), and equilibrium partitioning (EqP) for organics. Large differences in predictive ability among the SQGs were obtained when each approach was applied to the same southern California data set. Sediment quality guidelines that performed well in identifying nontoxic samples were not necessarily the best predictors of toxicity. In general, the mean ERMq, SQGQ1q, and consensus MECq approaches had a better overall predictive ability than the AET and EqP for organics approaches. In addition to evaluating the predictive ability of SQGs addressing chemical mixtures, the effect of an individual SQG value (DDT) was also evaluated for the mean ERMq with and without DDT. The mean ERMq without DDT had a better ability to predict toxic samples than the mean ERMq with DDT. Similarities in discriminatory ability between different approaches, variations in accuracy among SQG values for some chemicals, and the presence of complex mixtures of contaminants in most samples underscore the need to apply SQGs in combination, such as the mean quotient. Management objectives and SQG predictive ability using regional data should be determined beforehand so that the most appropriate SQG approach and critical values can be identified for specific applications. [source] Impact of animal waste lagoon effluents on chlorpyrifos degradation in soilsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2000Xinjiang Huang Abstract Animal-derived lagoon effluents are a good source of inorganic nutrients and organic matter; however, they may impact the degradation and transport of soil-applied pesticides. The degradation of chlorpyrifos in poultry-, swine-, and cow-derived effluents and effluent-soil matrices were studied using batch and column incubation studies. Chlorpyrifos was degraded by aerobic microbial processes in animal-derived lagoon effluents. Microbial community analysis by denaturing gradient gel electrophoresis of polymerase chain reaction-amplified 16S ribosomal ribonucleic acid genes showed that a single band became dominant in effluent during chlorpyrifos degradation. In soils, both biotic and abiotic degradation contributed significantly to the overall dissipation of chlorpyrifos. Large differences in degradation rates were observed between soils, with the fastest rate observed in soil with higher pH and cation-exchange capacity. Effluents appeared to have only a minor effect on chlorpyrifos degradation in soils, although effluent-induced increases in soil-solution pH over time may enhance hydrolysis by a few percent in low-pH soils. Soil properties, not effluent properties, appear to control chlorpyrifos degradation under laboratory conditions; however, the impact on changes in soil properties and microbial ecology with long-term effluent irrigation warrants further investigation. [source] Comparison of the specificity, stability and individual rate constants with respective activation parameters for the peptidase activity of cruzipain and its recombinant form, cruzain, from Trypanosoma cruziFEBS JOURNAL, Issue 24 2001Wagner A. S. Judice The Trypanosoma cruzi cysteine protease cruzipain contains a 130-amino-acid C-terminal extension, in addition to the catalytic domain. Natural cruzipain is a complex of isoforms, because of the simultaneous expression of several genes, and the presence of either high mannose-type, hybrid monoantennary-type or complex biantenary-type oligosacharide chains at Asn255 of the C-terminal extension. Cruzipain and its recombinant form without this extension (cruzain) were studied comparatively in this work. S2 to S2, subsite specificities of these enzymes were examined using four series of substrates derived from the internally quenched fluorescent peptide Abz-KLRFSKQ-EDDnp (Abz, ortho -aminobenzoic acid; EDDnp, N -(2,4-dinitrophenyl)-ethylenediamine). Large differences in the kinetic parameters were not observed between the enzymes; however, Km values were consistently lower for the hydrolysis of most of the substrates by cruzain. No difference in the pH,activity profile between the two enzymes was found, but in 1 m NaCl cruzipain presented a kcat value significantly higher than that of cruzain. The activation energy of denaturation for the enzymes did not differ significantly; however, a negative entropy value was observed for cruzipain denaturation whereas the value for cruzain was positive. We determined the individual rate constants (k1, substrate diffusion; k,1, substrate dissociation; k2, acylation; k3, deacylation) and the respective activation energies and entropies for hydrolysis of Abz-KLRFSKQ-EDDnp determining the temperature dependence of the Michaelis,Menten parameters kcat/Km and kcat as previously described [Ayala, Y.M. & Di Cera, E. (2000) Protein Sci.9, 1589,1593]. Differences between the two enzymes were clearly detected in the activation energies E1 and E,1, which are significantly higher for cruzipain. The corresponding ,S1 and ,S,1 were positive and significantly higher for cruzipain than for cruzain. These results indicate the presence of a larger energy barrier for cruzipain relating to substrate diffusion and dissociation, which could be related to the C-terminal extension and/or glycosylation state of cruzipain. [source] HCV RNA-dependent RNA polymerase replicates in vitro the 3, terminal region of the minus-strand viral RNA more efficiently than the 3, terminal region of the plus RNAFEBS JOURNAL, Issue 22 2001Sandrine Reigadas The NS5B protein, or RNA-dependent RNA polymerase of the hepatitis virus type C, catalyzes the replication of the viral genomic RNA. Little is known about the recognition domains of the viral genome by the NS5B. To better understand the initiation of RNA synthesis on HCV genomic RNA, we used in vitro transcribed RNAs as templates for in vitro RNA synthesis catalyzed by the HCV NS5B. These RNA templates contained different regions of the 3, end of either the plus or the minus RNA strands. Large differences were obtained depending on the template. A few products shorter than the template were synthesized by using the 3, UTR of the (+) strand RNA. In contrast the 341 nucleotides at the 3, end of the HCV minus-strand RNA were efficiently copied by the purified HCV NS5B in vitro. At least three elements were found to be involved in the high efficiency of the RNA synthesis directed by the HCV NS5B with templates derived from the 3, end of the minus-strand RNA: (a) the presence of a C residue as the 3, terminal nucleotide; (b) one or two G residues at positions +2 and +3; (c) other sequences and/or structures inside the following 42-nucleotide stretch. These results indicate that the 3, end of the minus-strand RNA of HCV possesses some sequences and structure elements well recognized by the purified NS5B. [source] Length of Stay for Older Adults Residing in Nursing Homes at the End of LifeJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 9 2010Anne Kelly MSW OBJECTIVES: To describe lengths of stay of nursing home decedents. DESIGN: Retrospective cohort study. SETTING: The Health and Retirement Study (HRS), a nationally representative survey of U.S. adults aged 50 and older. PARTICIPANTS: One thousand eight hundred seventeen nursing home residents who died between 1992 and 2006. MEASUREMENTS: The primary outcome was length of stay, defined as the number of months between nursing home admission and date of death. Covariates were demographic, social, and clinical factors drawn from the HRS interview conducted closest to the date of nursing home admission. RESULTS: The mean age of decedents was 83.3±9.0; 59.1% were female, and 81.5% were white. Median and mean length of stay before death were 5 months (interquartile range 1,20) and 13.7±18.4 months, respectively. Fifty-three percent died within 6 months of placement. Large differences in median length of stay were observed according to sex (men, 3 months vs women, 8 months) and net worth (highest quartile, 3 months vs lowest quartile, 9 months) (all P<.001). These differences persisted after adjustment for age, sex, marital status, net worth, geographic region, and diagnosed chronic conditions (cancer, hypertension, diabetes mellitus, lung disease, heart disease, and stroke). CONCLUSION: Nursing home lengths of stay are brief for the majority of decedents. Lengths of stay varied markedly according to factors related to social support. [source] On Being a Lone DissenterJOURNAL OF APPLIED SOCIAL PSYCHOLOGY, Issue 9 2005Donald Granberg Asch's (1956) research on group pressure to conform implied that it is difficult to be a lone dissenter. Extending this to the analysis of voting patterns in the U.S. Supreme Court's 1953-2001 terms, it was found that of 4,178 decisions, the 8-1 split was the least common (10%). Unanimous decisions were most common (35%), followed by 5-4 splits (21%), 6-3 splits (20%), and 7-2 splits (14%). Large differences were found among the 29 Justices serving during this period as to how often they were lone dissenters, led by Justice William Douglas, who issued lone dissents on about 6% of the decisions on which he voted. [source] Large differences in serum leptin levels between nonwesternized and westernized populations: the Kitava studyJOURNAL OF INTERNAL MEDICINE, Issue 6 2001S. Lindeberg Abstract.,Lindeberg S, Söderberg S, Ahrén B, Olsson T (Lund University; and Umeå University, Malmö, Sweden). Large differences in serum leptin levels between nonwesternized and westernized populations: the Kitava study. J Intern Med 2001; 249: 553,558. Objectives.,To compare serum leptin between nonwesternized and westernized populations. Setting., (i) The tropical island of Kitava, Trobriand Islands, Papua New Guinea and (ii) the Northern Sweden MONICA study population. Design.,Cross-sectional survey. Methods.,Fasting levels of serum leptin were analysed in 163 randomly selected Kitavans aged 20,86 years and in 224 Swedes aged 25,74. Main outcome measures.,Mean and determinants of serum leptin. Results.,Geometric mean of serum leptin in Kitavan males and females were 1.5 and 4.0 vs. 4.9 and 13.8 ng mL,1 in Swedish male and females (P < 0.0001 for both sexes). In Kitavans, observed geometric mean were close to predicted levels (1.8 ng mL,1 for males and 4.5 ng mL,1 for females) based on multiple linear regression equations including body mass index (BMI), triceps skinfolds (TSF) and age from the Swedish population-based sample. In Kitavans serum leptin was positively related to TSF amongst both sexes and, amongst females, to BMI. In Kitavans leptin was not related to fasting serum insulin. TSF explained 55% of the variation of leptin amongst females. There was a slight age-related increase of leptin amongst males. In Kitava leptin was not related to fasting serum insulin which was substantially lower than in Sweden. Conclusion.,The low concentrations of serum leptin amongst Kitavans probably relates to the absence of overweight and hyperinsulinaemia. At a population level serum leptin can apparently be predicted from simple measures of adiposity. [source] Assessing the Severity of Hazardous Drinking and Related Consequences Among Incarcerated WomenALCOHOLISM, Issue 5 2010David R. Strong Background:, Recent epidemiological efforts have demonstrated the utility of measuring individual differences in the severity of alcohol use along a single severity continuum marked by alcohol-related problems, symptoms of alcohol dependence, and the social consequences of drinking. Translation of this utility to specialized clinical populations is not assured. The expected inter-relationships among problems, symptoms and consequences, and enhanced sensitivity of combined assessments require confirmation in applied clinical settings. Method:, Subjects were 245 incarcerated women who met Alcohol Use Disorders Identification Test criteria for hazardous use of alcohol. Participants were recruited from a statewide adult correctional facility for an ongoing clinical trial testing the effectiveness of brief motivational interviewing on alcohol use and HIV risk behaviors. Participants ranged in age from 18 to 56 (M = 34.1, SD = 8.9), 71.4% were Caucasian, and 65.7% reported <12 years of education. Results:, Analyses suggested that the 6 problems of alcohol abuse, 7 symptoms for alcohol dependence, and 14 alcohol-related social consequences loaded to a single factor (0.38 to 0.85) that formed a continuum of alcohol severity. Contrary to epidemiological studies, physical fights and being arrested were the most prevalent consequences and were associated with lower alcohol severity in this population. Three of the five items that discriminated best between higher and lower alcohol severity were related to familial and relationship consequences. Conclusions:, Consistent with epidemiological studies, alcohol severity can be measured among incarcerated hazardously drinking women on a single continuum that includes alcohol problems, symptoms, and social consequences. Replication of the expected alignment of problems and symptoms supports the construct validity of the continuum and further challenges the proposed hierarchical structure of abuse/dependence distinction. Large differences in rates of specific consequences and observed effectiveness of tailored social consequence items suggest the benefits of cross-sample validation to improve evaluation of clinical outcomes. [source] Forage quality and tannin concentration and composition of a collection of the tropical shrub legume Flemingia macrophyllaJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2006Meike S Andersson Abstract A collection of 23 Flemingia macrophylla (Willd.) Merrill accessions of different growth habits and contrasting digestibility and one Flemingia stricta reference accession were assessed for forage quality with particular emphasis on digestibility, condensed tannin concentration and fiber content. Large differences in in vitro dry matter digestibility (IVDMD) (356 to 598 g kg,1), content of crude protein (CP) (121 to 254 g kg,1) and extractable condensed tannins (CT) (0 to 268 g kg,1), protein-binding capacity of extractable CT or astringency (1.7 to 7.9 protein-binding entities) (PBE) and monomer composition of extractable CT were detected. IVDMD and extractable CT were negatively correlated and extractable CT was positively correlated with protein-binding capacity. Prodelphinidin was positively and propelargonidin negatively correlated with protein-binding capacity of extractable CT. The accessions CIAT 18438, CIAT 21083, CIAT 21090 and CIAT 22082 were superior to the most widely used accession CIAT 17403 in terms of forage quality and could be an option in production systems with acid infertile soils. In future evaluations, particular attention needs to be paid to chemical and structural features related to the composition of extractable CT and their effect on nitrogen utilization by ruminants. Copyright © 2006 Society of Chemical Industry [source] A detailed assessment of the pattern of moxidectin tissue distribution after pour-on treatment in calvesJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 6 2003J. M. Sallovitz The use of topical (pour-on) administration of endectocide drugs in cattle has reached world-wide acceptance. However, only limited information is available on the kinetic behaviour for topically administered moxidectin (MXD). To improve our understanding of the relationship between pharmacokinetics and efficacy for pour-on preparations, MXD concentration profiles were measured in tissues of endo- and ectoparasites location over 35 days postadministration. MXD distribution to the fluid content and mucosal tissue of the abomasum and different intestinal sections (duodenum, ileum, caecum and colon) was assessed. The comparative patterns of MXD distribution to skin and hypodermic tissue from different anatomical sites (backline, rib cage, thigh and face) were also investigated following the pour-on administration. Wide tissue distribution and long residence time characterized the kinetics of topically administered MXD. MXD was recovered between 1 and 35 days post-treatment in all the tissues investigated. The highest MXD availabilities were observed in the skin layers at the site of administration (backline) and in the fat tissue. The fluid contents of different intestinal sections showed MXD concentrations higher than those measured in their respective mucosal tissues, particularly at day 1 post-treatment. MXD concentrations in the skin (epidermis + dermis) were higher than those measured in the hypodermic tissue. Large differences in the availability of MXD in skin from different anatomical regions (backline > rib cage > thigh > face) were observed. The low plasma and the high skin availability indicate the formation of a skin depot of the drug, being released slowly to the plasma and reaching concentrations in systemic tissues (abomasal mucosa, lungs, etc.) similar to those measured after subcutaneous administration. These findings demonstrate that target parasites may be exposed to markedly different drug concentrations according to their location sites, which is particularly relevant for ectoparasites located in different anatomical regions. Knowledge of the tissue distribution of topically administered endectocides contributes to understand the differences observed in efficacy and/or persistence of activity and to optimize their use in cattle. [source] Intraclutch egg-size variation in acanthosomatid bugs: adaptive allocation of maternal investment?OIKOS, Issue 2 2001Shin-ichi Kudo If there are differences in predation risk among the offspring within a clutch, parents may allocate less resources to the offspring facing higher risk. I examined parental investment in terms of egg size within clutches in five species of stink bugs (Heteroptera, Acanthosomatidae). In subsocial Elasmucha and Sastragala species, the female guards her eggs and first-instar nymphs against invertebrate predators by covering her clutch with her body. Large differences in survival from predation between offspring at the centre and offspring at the periphery of the clutch have been reported in such subsocial insects. I found that Elasmucha and Sastragala females laid significantly smaller eggs in the peripheral (and thus more vulnerable) part of the clutch. Phenotypic trade-offs between egg size and clutch size were detected in these subsocial species. Egg size was positively correlated with hatched first-instar nymph size: smaller nymphs hatched from smaller peripheral eggs. In asocial Elasmostethus humeralis, however, no significant difference in size was detected between the eggs at the centre of and those at the periphery of the clutch. Thus, in subsocial acanthosomatid bugs, females seem to allocate their resources according to the different predation risks faced by the offspring within the clutch. [source] Water deficits and hydraulic limits to leaf water supplyPLANT CELL & ENVIRONMENT, Issue 2 2002J. S. Sperry Abstract Many aspects of plant water use , particularly in response to soil drought , may have as their basis the alteration of hydraulic conductance from soil to canopy. The regulation of plant water potential (,) by stomatal control and leaf area adjustment may be necessary to maximize water uptake on the one hand, while avoiding loss of hydraulic contact with the soil water on the other. Modelling the changes in hydraulic conductance with pressure gradients in the continuum allows the prediction of water use as a function of soil environment and plant architectural and xylem traits. Large differences in water use between species can be attributed in part to differences in their ,hydraulic equipment' that is presumably optimized for drawing water from a particular temporal and spatial niche in the soil environment. A number of studies have identified hydraulic limits as the cause of partial or complete foliar dieback in response to drought. The interactions between root:shoot ratio, rooting depth, xylem properties, and soil properties in influencing the limits to canopy water supply can be used to predict which combinations should optimize water use in a given circumstance. The hydraulic approach can improve our understanding of the coupling of canopy processes to soil environment, and the adaptive significance of stomatal behaviour. [source] Electrokaryotypes of Macronuclei of Several Paramecium SpeciesTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 4 2002MARIA S. RAUTIAN ABSTRACT A comparative study of macronuclear DNA molecules from the following Paramecium species+the P. aurelia complex, P. caudatum, P. bursaria, P. putrinum and P. multimicronucleatum was performed using pulsed-fleld gel electrophoresis. The electrophoretic pattern was constant and unique for each species, and is referred to herein as its electrokaryotype. Large differences were observed between Paramecium species according to the range and major size of macronuclear DNA fragments, while different strains of the same species, even belonging to different syngens, were characterized by the same electrokaryotype. In this respect sibling species from the P. aurelia complex are as similar as syngens in other Paramecium species, but are unlike conventional species. The principles and value of electrokaryotype analysis for application to ciliates are discussed. [source] Ovule differences between single-kernelled and double-kernelled fruits in almond (Prunus dulcis)ANNALS OF APPLIED BIOLOGY, Issue 3 2000J EGEA Summary In order to detect differences between almond cultivars that commonly produce one or two seeds, we compared ovule sizes and developmental stages at anthesis and three days after anthesis. The results showed that the presence of only small differences in size between primary and secondary ovules during flowering seemed to be a necessary but not sufficient condition for the production of double-kernelled fruits. In contrast, differences in the developmental stage of both ovules did not prevent the production of double kernels. Large differences in ovule size at anthesis or in the following days resulted in fruits with single seeds. The behaviour of the secondary ovules in cultivars producing fruit with single seeds was very different, even in closely related cultivars. The degeneration of the secondary ovule seems to be genetically programmed and follows a genotype-dependent pattern. [source] Induction of apoptosis by A3 adenosine receptor agonist N6 -(3-iodobenzyl)-adenosine-5,- N -methylcarboxamide in human leukaemia cells: a possible involvement of intracellular mechanismACTA PHYSIOLOGICA, Issue 2 2010P. Mlejnek Abstract Aim:, The sensitivity of cancer cells which exhibit multi-drug resistance phenotype to A3 adenosine receptor (A3AR) agonist N6 -(3-iodobenzyl)-adenosine-5,- N -methylcarboxamide (IB-MECA) was studied. Methods:, To establish direct relationship between P-glycoprotein (P-gp, ABCB1 and MDR1) expression and IB-MECA induced cell death, a straightforward method for precise estimation of intracellular level of this A3AR agonist was developed. Results:, We subjected three human leukaemia cell lines HL-60, K562 and K562/HHT to treatment with micromolar concentrations of IB-MECA. Although all cell lines used expressed A3AR, there was a large difference in their sensitivity to IB-MECA. While HL-60 and K562 cells were almost equally sensitive, the K562/HHT cells, which exhibit a multi-drug resistance phenotype because of overexpression of P-gp, were significantly more resistant. We found that the intracellular level of IB-MECA in K562/HHT cells was approx. 10 times lower than those in HL-60 or K562 cells. Inhibitors of P-gp, including cyclosporine A (CsA) and verapamil (Vpa), increased the intracellular level of IB-MECA and reversed the resistance of K562/HHT cells to this drug. Accordingly, shRNA-mediated down-regulation of P-gp significantly increased the intracellular level of IB-MECA in K562/HHT cells which simultaneously exhibited reduced resistance to this A3AR agonist. In addition, an in vitro enzyme-based assay provided evidence that IB-MECA might serve as a substrate for P-gp. Conclusion:, Our results suggest that P-gp overexpression prevents cells from IB-MECA induced apoptosis despite the A3AR expression. Pro-apoptotic effect of IB-MECA seemed to strongly depend on its intracellular accumulation rather than on its interaction with A3AR. [source] A comparison of spatial interpolation methods to estimate continuous wind speed surfaces using irregularly distributed data from England and WalesINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 7 2008W. Luo Abstract Seven methods of spatial interpolation were compared to determine their suitability for estimating daily mean wind speed surfaces, from data recorded at nearly 190 locations across England and Wales. The eventual purpose of producing such surfaces is to help estimate the daily spread of pathogens causing crop diseases as they move across regions. The interpolation techniques included four deterministic and three geostatistical methods. Quantitative assessment of the continuous surfaces showed that there was a large difference between the accuracy of the seven interpolation methods and that the geostatistical methods were superior to deterministic methods. Further analyses, testing the reliability of the results, showed that measurement accuracy, density, distribution and spatial variability had a substantial influence on the accuracy of the interpolation methods. Independent wind speed data from ten other dates were used to confirm the robustness of the best interpolation methods. © Crown copyright 2007. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. [source] A decision support methodology for increasing public investment efficiency in Brazilian agrarian reformINTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH, Issue 1 2009Leonardo Melgarejo Abstract The Brazilian Agrarian Reform Program has subsidized the settlement of over 425,000 destitute families on previously unproductive land in what has become a very effective vehicle for social inclusion and productivity growth for those settlers who reach the final stage of the process and receive definitive title to the land. Unfortunately, there is a large difference in efficiency and productivity between more and less successful settlements , fewer than 10% of relocated families have received title and over 25% of them have abandoned the property to which they were assigned. This paper presents a decision support methodology for increasing the efficiency of public investments in agrarian reform that includes a data envelopment analysis model and a mechanism for building consensus among the various constituencies of the agrarian reform process, who not infrequently have conflicting objectives. The OR model described herein uses principal component analysis and data envelopment analysis to identify the most important success factors for relocated families leading to an increase in the chance of both autonomous integration with the market economy and definitive entitlement by these displaced families as well as an increase in the predictability of future settlement success. The model was implemented successfully in Rio Grande do Sul, the southernmost state of Brazil, and was partially used in a pilot project for the countrywide agrarian reform accelerated consolidation program. [source] Charge and Mass Transfer Across the Metal/Solution InterfaceISRAEL JOURNAL OF CHEMISTRY, Issue 3-4 2008Eliezer Gileadi Electrode reactions are characterized by charge transfer across the interface. The charge can be carried by electrons or by ions. It is shown here that when both mass and charge cross the interface, the charge must be carried by the ionic species, not by the electrons, as a result of the very large difference in the time scale for electron and ion transfer. A prime example of charge transfer by ions is metal deposition. It is proposed that ion transfer occurs by migration of the ions across the interface, under the influence of the high electrostatic field in the double layer. The rate constants observed for metal deposition are comparable to those for outer-sphere charge transfer. These unexpectedly high rate constants for metal deposition are explained by a model in which removal of the solvation shell and reduction of the effective charge on the metal ion occur in many small steps, and a make-before-break mechanism exists, which lowers the total Gibbs energy of the system as it moves along the reaction coordinate from the initial to the final state. [source] Rotation axis analysis of deformed crystals by X-rays and electronsJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2008András Borbély X-ray and electron backscatter diffraction (EBSD) have been applied to investigate misorientation distributions in copper single crystals plastically deformed in single and multiple slip. The misorientation distributions are represented by `rocking curves' about specific rotation axes. Very good agreement for the rocking curves established by the two methods was obtained, despite the large difference between their resolution depths. Following this agreement, a new rotation axis imaging scheme, based on the EBSD data, is proposed in order to visualize the crystallite blocks and characterize the nature of their dislocation boundaries. [source] Use of trace elements in feathers of sand martin Riparia riparia for identifying moulting areasJOURNAL OF AVIAN BIOLOGY, Issue 3 2003Tibor Szép We investigated whether trace elements in tail feathers of an insectivorous and long-distance migratory bird species could be used to identify moulting areas and hence migratory pathways. We analysed tail feathers from birds of different age and sex collected from a range of different breeding sites across Europe. The site of moult had a large effect on elemental composition of feathers of birds, both at the European and African moulting sites. Analysis of feathers of nestlings with known origin suggested that the elemental composition of feathers depended largely upon the micro-geographical location of the colony. The distance between moulting areas could not explain the level of differences in trace elements. Analysis of feathers grown by the same individuals on the African wintering grounds and in the following breeding season in Europe showed a large difference in composition indicating that moulting site affects elemental composition. Tail feathers moulted in winter in Africa by adults breeding in different European regions differed markedly in elemental composition, indicating that they used different moulting areas. Analysis of tail feathers of the same adult individuals in two consecutive years showed that sand martins in their first and second wintering season grew feathers with largely similar elemental composition, although the amounts of several elements in tail feathers of the older birds was lower. There was no difference between the sexes in the elemental composition of their feathers grown in Africa. Investigation of the trace element composition of feathers could be a useful method for studying similarity among groups of individuals in their use of moulting areas. [source] Persistent Organic Pollutants in Fish Oil Supplements on the Canadian Market: Polychlorinated Biphenyls and Organochlorine InsecticidesJOURNAL OF FOOD SCIENCE, Issue 1 2009Dorothea F.K. Rawn ABSTRACT:, Fish and seal oil dietary supplements, marketed to be rich in omega-3 fatty acids, are frequently consumed by Canadians. Samples of these supplements (n,= 30) were collected in Vancouver, Canada, between 2005 and 2007. All oil supplements were analyzed for polychlorinated biphenyls (PCBs) and organochlorine insecticides (OCs) and each sample was found to contain detectable residues. The highest ,PCB and ,DDT (1,1,1-trichloro-di-(4-chlorophenyl)ethane) concentrations (10400 ng/g and 3310 ng/g, respectively) were found in a shark oil sample while lowest levels were found in supplements prepared using mixed fish oils (anchovy, mackerel, and sardine) (0.711 ng ,PCB/g and 0.189 ng ,DDT/g). Mean ,PCB concentrations in oil supplements were 34.5, 24.2, 25.1, 95.3, 12.0, 5260, 321, and 519 ng/g in unidentified fish, mixed fish containing no salmon, mixed fish with salmon, salmon, vegetable with mixed fish, shark, menhaden (n,= 1), and seal (n,= 1), respectively. Maximum concentrations of the other OCs were generally observed in the seal oil. The hexachlorinated PCB congeners were the dominant contributors to ,PCB levels, while ,DDT was the greatest contributor to organochlorine levels. Intake estimates were made using maximum dosages on manufacturers' labels and results varied widely due to the large difference in residue concentrations obtained. Average ,PCB and ,DDT intakes were calculated to be 736 ± 2840 ng/d and 304 ± 948 ng/d, respectively. [source] Effects of Heat Pretreatment on Lipid and Pigments of Freeze-Dried SpinachJOURNAL OF FOOD SCIENCE, Issue 8 2001E. Cho ABSTRACT: Heat pretreatment resulted in decreases in drying yield and glycolipids (GL) and an increase in neutral lipids (NL). Triacylglycerol and free sterols in NL and sterylglycosides and monogalactosyldiglycerides in GL were more stable during heat pretreatment. Phosphatidylglycerol, phosphatidylethanolamine, and phosphatidic acid among phospholipid subclasses were more susceptible. There was no large difference in fatty-acid composition of spinach lipids by heat pretreatment. However, a significant decrease in linolenic acid and increases in oleic and hexadecenoic acids were observed in NL. Contents of chlorophyll, lutein, and ,-carotene in spinach decreased by heat pretreatment, with the least decrease in lutein. [source] Hydrogen separation of methyltriethoxysilane templating silica membraneAICHE JOURNAL, Issue 12 2007Jong-Ho Moon Abstract Hydrogen separation on microporous methyltriethoxysilane-templating silica composite/,-alumina membranes (below MTES membrane) was studied using three binary gas mixtures: H2/N2, H2/CO2, and H2/CH4. The characteristics of unsteady and steady-state permeation/separation on the MTES membrane were compared to each other. Although permeation flux in the H2/N2 mixture was comparatively low, H2 selectivity was high (H2/N2 SF , 30,60). On the contrary, the H2/CO2 mixture showed high permeation flux but low H2 selectivity (H2/CO2 SF , 1.5,6.5). The H2/CH4 mixture showed a large difference between permselectivity (28,48) and separation factor (10,22). Results from this study revealed that it was difficult to predict the separation factor using the one-component permeation ratio (permselectivity) over the experimental range tested. These separation characteristics could be primarily ascribed to the molecular size and structure of each gas, which likely contributed to steric hindrance or molecular sieving within the membrane pore. In addition, the adsorption affinity of each molecule on the membrane surface acted as a key factor in separation performance because it significantly influenced surface diffusion. The generalized Maxwell-Stefan model incorporating the dust gas model, and the Langmuir model could successfully predict the transient and steady-state permeation/separation. © 2007 American Institute of Chemical Engineers AIChE J, 2007 [source] Light-Enhanced Resistance to Magnaporthe grisea Infection in the Rice Sekiguchi Lesion MutantsJOURNAL OF PHYTOPATHOLOGY, Issue 4 2000S. Arase The rice sl mutant showed two types of responses to Magnaporthe grisea infection by light treatments. One was an sl -mutant-type response characterized by Sekiguchi lesion expression under light waves of 400,700 nm, and the other was a wild-type response characterized by blast and/or necrotic spot lesion expression in the dark or at wavelength between 290 and 330 nm. There was a large difference in the resistance to M. grisea infection between the mutant- and wild-type responses in the rice sl mutant. When the mutant-type response was induced in the rice sl mutant, the disease resistance was enhanced relative to that in the wild-type response. Enhanced resistance was demonstrated by two components: (a) the number of Sekiguchi lesions was reduced relative to that of blast or necrotic lesions; (b) sporulation of M. grisea was not induced in Sekiguchi lesions. The enhanced resistance was dependent on light of 400,700 nm. Zusammenfassung In Abhängigkeit von einer Bestrahlung mit Licht zeigte die sl -Mutante von Reis zwei Typen von Reaktionen auf Magnaporthe-grisea -Infektionen. Zum einen trat eine Reaktion vom sl-Mutantentyp auf, charakterisiert durch Expression von Sekiguchi-Läsionen bei Wellenlängen von 400 bi 700 nm. Zum anderen war eine Wildtypreak-tion festzustellen, bei der es zu Bräune und/oder Expression nekrotischer Flecken bei Dunkelheit oder bei Wellenlängen zwischen 290 und 330 nm kam. Hinsichtlich der Resistenz gegen die M.-grisea -Infektion bestand ein großer Unterschied zwischen den Mutanten- und den Wildtypreaktionen der sl -Mutante des Reis. Wurde die Reaktion vom Mutantentyp in der sl -Mutante induziert, so war die Krankheitsresistenz im Vergleich zur Wildtypreaktion erhöht. Die höhere Resistenz zeigte sich an zwei Komponenten: (a) die Zahl der Sekiguchi-Läsionen war kleiner als die der braunen bzw. nekrotischen Läsionen (b) in Sekiguchi-Läsionen wurde keine Sporulation von M. grisea induziert. Die erhöhte Resistenz war abhängig von Licht im Wellenlängenbereich 400 bis 700 nm. [source] Longitudinal Associations Between Alcohol Problems and Depressive Symptoms: Early Adolescence Through Early AdulthoodALCOHOLISM, Issue 1 2009Naomi R. Marmorstein Background:, Alcohol use-related problems and depressive symptoms are clearly associated with each other, but results regarding the nature of this association have been inconsistent. In addition, the possible moderating effects of age and gender have not been comprehensively examined. The goals of this study were to clarify: (i) how depressive symptoms affect the levels and trajectory of alcohol use-related problems, (ii) how alcohol use-related problems affect the levels and trajectory of depressive symptoms, and (iii) whether there are differences in these associations at different points in development or between males and females. Methods:, Participants for this study were drawn from the National Longitudinal Study of Adolescent Health (AddHealth) data set, a community-based sample of 20,728 adolescents followed from adolescence through early adulthood. Multilevel models were used to assess how each problem affected the level and rate of change in the other problem over time; gender was considered as a possible moderator of these associations. Results:, The results indicated that alcohol use-related problems and depressive symptoms had reciprocal, positive associations with each other during the period from early adolescence through early adulthood; however, these effects differed somewhat by gender and age. High levels of depressive symptoms were associated with higher initial levels of alcohol problems (particularly among females), as well as faster increases in alcohol problems over time among males. High levels of alcohol problems were associated with higher initial levels of depressive symptoms (particularly among females), as well as less curvature in the slope of depressive symptoms so that although there was a large difference between people with high and low depressive symptoms in early adolescence, by early adulthood the difference was smaller (particularly among females). Conclusions:, These results highlight the importance of examining gender and age in studies on the associations between affective disorders and substance use disorders. [source] Global Daily Reference Evapotranspiration Modeling and Evaluation,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 4 2008G.B. Senay Abstract:, Accurate and reliable evapotranspiration (ET) datasets are crucial in regional water and energy balance studies. Due to the complex instrumentation requirements, actual ET values are generally estimated from reference ET values by adjustment factors using coefficients for water stress and vegetation conditions, commonly referred to as crop coefficients. Until recently, the modeling of reference ET has been solely based on important weather variables collected from weather stations that are generally located in selected agro-climatic locations. Since 2001, the National Oceanic and Atmospheric Administration's Global Data Assimilation System (GDAS) has been producing six-hourly climate parameter datasets that are used to calculate daily reference ET for the whole globe at 1-degree spatial resolution. The U.S. Geological Survey Center for Earth Resources Observation and Science has been producing daily reference ET (ETo) since 2001, and it has been used on a variety of operational hydrological models for drought and streamflow monitoring all over the world. With the increasing availability of local station-based reference ET estimates, we evaluated the GDAS-based reference ET estimates using data from the California Irrigation Management Information System (CIMIS). Daily CIMIS reference ET estimates from 85 stations were compared with GDAS-based reference ET at different spatial and temporal scales using five-year daily data from 2002 through 2006. Despite the large difference in spatial scale (point vs. ,100 km grid cell) between the two datasets, the correlations between station-based ET and GDAS-ET were very high, exceeding 0.97 on a daily basis to more than 0.99 on time scales of more than 10 days. Both the temporal and spatial correspondences in trend/pattern and magnitudes between the two datasets were satisfactory, suggesting the reliability of using GDAS parameter-based reference ET for regional water and energy balance studies in many parts of the world. While the study revealed the potential of GDAS ETo for large-scale hydrological applications, site-specific use of GDAS ETo in complex hydro-climatic regions such as coastal areas and rugged terrain may require the application of bias correction and/or disaggregation of the GDAS ETo using downscaling techniques. [source] A kinetic study of the reactions of (+)-catechin with aldehydes derived from toasted oakJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2007Marie-Françoise Nonier Abstract The reactions between (+)-catechin and representative oak wood furanic (furfuraldehyde, 5-hydroxymethylfurfuraldehyde and 5-methylfurfuraldehyde) and phenolic (vanillin and syringaldehyde) aldehydes in a wine-like model solution were studied and the corresponding condensation kinetics at pH 3.0 and 3.5 were compared. A comparative study on the reactivity of these two representative families of aldehydes towards (+)-catechin showed a large difference between them. When incubated separately with (+)-catechin at both pH values, the reactions were faster with furanic aldehydes than with phenolic aldehydes. In mixtures containing (+)-catechin and individual aldehydes, new compounds were identified by high-performance liquid chromatography (HPLC)/UV,visible detection, some of which were characterised by liquid chromatography/electrospray ionisation mass spectrometry (LC/ESI-MS). The increase in solution absorbance with time was closely linked to these new products. Copyright © 2007 Society of Chemical Industry [source] Mechanistic comparison of blood undergoing laser photocoagulation at 532 and 1,064 nmLASERS IN SURGERY AND MEDICINE, Issue 2 2005John F. Black PhD Abstract Background and Objectives We seek to compare and contrast the mechanisms of blood photocoagulation under 532 and 1,064 nm laser irradiation in vitro in order to better understand the in vivo observations. We also seek to validate a finite element model (FEM) developed to study the thermodynamics of coagulation. Study Design/Materials and Methods We study the photocoagulation of whole blood in vitro at 532 and 1,064 nm using time-domain spectroscopic and optical coherence tomography (OCT)-based imaging techniques. We model the coagulation using an FEM program that includes the latent heat of vaporization (LHV) of water, consideration of the pulse shape of the laser, and the bathochromic shift in the hemoglobin absorption spectrum. Results We find significant similarities in the spectroscopic, chemical, and structural changes occurring in hemoglobin and in the blood matrix during photocoagulation despite the very large difference in the absorption coefficients. The more uniform temperature profile developed by the deeper-penetrating 1,064 nm laser allows us to resolve the structural phase transition in the red blood cells (going from biconcave disc to spherocyte) and the chemical transition creating met-hemoglobin. We find that the RBC morphology transition happens first, and that the met-Hb transition happens at a much higher temperature (,>,90°C) than is found in slow bath heating. The FEM analysis with the LHV constraint and bathochromic shift predicts accurately the imaging results in both cases, and can be used to show that at 1,064 nm there is the potential for a runaway increase in absorption during the laser pulse. Conclusions Photothermally mediated processes dominate the in vitro coagulation dynamics in both regimes despite the difference in absorption coefficients. There is a significant risk under 1,064 nm irradiation of vascular lesions in vivo that the dynamic optical properties of blood will cause runaway absorption and heating. This may in turn explain some recent results at this wavelength where full-thickness burns resulted from laser treatment. Lasers Surg. Med. 36:155,165, 2005. © 2005 Wiley-Liss, Inc. [source] Cryogen spray cooling: Effects of droplet size and spray density on heat removalLASERS IN SURGERY AND MEDICINE, Issue 2 2001Brian M. Pikkula BS Abstract Background and Objective Cryogen spray cooling (CSC) is an effective method to reduce or eliminate non-specific injury to the epidermis during laser treatment of various dermatological disorders. In previous CSC investigations, fuel injectors have been used to deliver the cryogen onto the skin surface. The objective of this study was to examine cryogen atomization and heat removal characteristics of various cryogen delivery devices. Study Design/Materials and Methods Various cryogen delivery device types including fuel injectors, atomizers, and a device currently used in clinical settings were investigated. Cryogen mass was measured at the delivery device output orifice. Cryogen droplet size profiling for various cryogen delivery devices was estimated by optically imaging the droplets in flight. Heat removal for various cryogen delivery devices was estimated over a range of spraying distances by temperature measurements in an skin phantom used in conjunction with an inverse heat conduction model. Results A substantial range of mass outputs were measured for the cryogen delivery devices while heat removal varied by less than a factor of two. Droplet profiling demonstrated differences in droplet size and spray density. Conclusions Results of this study show that variation in heat removal by different cryogen delivery devices is modest despite the relatively large difference in cryogen mass output and droplet size. A non-linear relationship between heat removal by various devices and droplet size and spray density was observed. Lasers Surg. Med. 28:103,112, 2001. © 2001 Wiley-Liss, Inc. [source] Pronounced stereospecificity of 1H, 13C, 15N and 77Se shielding constants in the selenophenyl oximes as shown by NMR spectroscopy and GIAO calculationsMAGNETIC RESONANCE IN CHEMISTRY, Issue 10 2009Andrei V. Afonin Abstract In the 1H and 13C NMR spectra of 1-(2-selenophenyl)-1-alkanone oximes, the 1H, the 13C-3 and 13C-5 signals of the selenophene ring are shifted by 0.1,0.4, 2.5,3.0 and 5.5,6.0 ppm, respectively, to higher frequencies, whereas those of the 13C-1, 13C-2 and 13C-4 carbons are shifted by 4,5, ,11 and ,1.7 ppm to lower frequencies on going from the E to Z isomer. The 15N chemical shift of the oximic nitrogen is larger by 13,16 ppm in the E isomer relative to the Z isomer. An extraordinarily large difference (above 90 ppm) between the 77Se resonance positions is revealed in the studied oxime isomers, the 77Se peak being shifted to higher frequencies in the Z isomer. The trends in the changes of the measured chemical shifts are well reproduced by the GIAO calculations of the 1H, 13C, 15N and 77Se shielding constants in the energy-favorable conformation with the syn orientation of theCNOH group relative to the selenophene ring. Copyright © 2009 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||