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Moderate Differences (moderate + difference)
Selected AbstractsInfluence of stationary phase chemistry and mobile-phase composition on retention, selectivity, and MS response in hydrophilic interaction chromatographyJOURNAL OF SEPARATION SCIENCE, JSS, Issue 6-7 2010Kenneth J. Fountain Abstract A comprehensive retention and selectivity characterization of several hydrophilic interaction chromatography (HILIC) stationary phases was performed with 28 test probes in order to study the influence of particle type, surface chemistry, and mobile-phase pH on chromatographic retention, selectivity, and MS response. Selectivity differences were compared for columns operated at both low and high pH, while ESI-MS was used to study the effects of mobile-phase pH on signal response. Additionally, acetone was explored as a potential alternative to ACN as the weak HILIC solvent. Moderate differences in selectivity were observed on the same column operated at different pH, mostly due to acidic compounds. In addition, the MS response increased when a high pH mobile phase was used, particularly for analytes that were ionized with negative ESI-MS. Even larger selectivity differences were observed for different stationary phases evaluated with the same mobile phase. Acetone was not a suitable replacement for ACN in routine HILIC separations due to differences in selectivity and MS response. Finally, the data from this study were used to establish guidelines for rapid HILIC method development of polar compounds, which is demonstrated with a mixture of histidine dipeptides and organophosphonate nerve agent metabolites. [source] Acute stress symptoms during the second Lebanon war in a random sample of Israeli citizensJOURNAL OF TRAUMATIC STRESS, Issue 1 2008Miri Cohen The aims of this study were to assess prevalence of acute stress disorder (ASD) and acute stress symptoms (ASS) in Israel during the second Lebanon war. A telephone survey was conducted in July 2006 of a random sample of 235 residents of northern Israel, who were subjected to missile attacks, and of central Israel, who were not subjected to missile attacks. Results indicate that ASS scores were higher in the northern respondents; 6.8% of the northern sample and 3.9% of the central sample met ASD criteria. Appearance of each symptom ranged from 15.4% for dissociative to 88.4% for reexperiencing, with significant differences between northern and central respondents only for reexperiencing and arousal. A low ASD rate and a moderate difference between areas subjected and not subjected to attack were found. [source] Microscopic theory for intersubband spontaneous emissionPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 2 2007M. F. Pereira Jr. Abstract The amplified spontaneous emission spectra of quantum-cascade laser structures is computed with a Keldysh Green's functions theory. We show that the emission spectra are sharpened in comparison to gain spectra due to wave guide propagation. In addition the different dependence on level occupation causes moderate differences between gain and emission peak positions. Our fit-parameter-free theory is valid in ranges of strong nonequilibrium, where fit-parameters do not even exist. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] High proportion of protected minke whales sold on Japanese markets is due to illegal, unreported or unregulated exploitationANIMAL CONSERVATION, Issue 5 2009V. Lukoschek Abstract Whale meat products sold on Japanese markets originate from two stocks of North Pacific (NP) minke whales Balaenoptera acutorostrata scammoni: the depleted J-stock, which has been protected since 1986 but continues to be killed as fisheries ,bycatch', and the more abundant O-stock, which is hunted under special permit (scientific whaling). We investigated the geographic distribution and temporal changes in stock composition of NP minke whale products sold on Japanese markets between December 1997 and June 2004. From nearly 1200 ,whale meat' products purchased during this time, 250 were identified as NP minke whales by phylogenetic analysis of mitochondrial DNA (mtDNA) sequences. The 250 NP minke whale products were found to represent 201 unique ,market individuals' after exclusion of replicate products using microsatellite genotypes. Market individuals were further classified into four mtDNA haplogroups, three of which are characteristic of the J-stock (J-type) and one characteristic of the O-stock (O-type). There were moderate differences in the proportions of J-type individuals found in coastal prefectures, perhaps reflecting regional differences in the sale of local bycatch, but no significant difference across time. The absence of a change over time was inconsistent with the four- to fivefold increase in reported bycatch, from an average of 25,122 whales year,1, following a 2001 regulation allowing commercial sale of whales taken as bycatch. Using a mixed-stock analysis based on haplogroup frequencies over the entire survey period, we estimated that 46.1% (se, 4.2%) of all market individuals originated from the J-stock. This estimate of illegal, unreported or unregulated (IUU) exploitation is higher than expected from the officially reported bycatch, suggesting either large-scale under-reporting and/or unrecognized takes of J-stock minke whales from Pacific coastal waters by the scientific hunt. Our estimates of the true level of IUU exploitation have important implications for recovery of this depleted coastal stock. [source] Survival, growth and dressing traits of triploid hybrids between rainbow trout and three charr speciesAQUACULTURE RESEARCH, Issue 4 2000J M. Blanc Triploid hybrids between female rainbow trout Oncorhynchus mykiss and male brook charr Salvelinus fontinalis, Arctic charr S. alpinus and lake charr S. namaycush, together with diploid and triploid rainbow trout controls from the same dams, were tested in freshwater farming up to their fourth year of life. All hybrids displayed lower survival rates than the controls, the weakest genotype being the Arctic charr hybrid. Mortalities were mostly observed at the embryonic and larval stages and at the adult stage as a consequence of male sexual maturation. Growth of all hybrids was hindered (compared with controls) during the first year, but only moderate differences remained after 3 years. Sexual maturation resulted in a weight inferiority of males in all genotypes. As to carcass traits, female hybrids displayed a slightly higher dressing percentage than female triploid rainbow trout, as a result of lower visceral losses. These results are discussed with reference to hybrid resistance to rhabdoviruses from the viewpoint of fish farming improvement. [source] Herpetofaunal Diversity and Abundance in Tropical Upland Forests of Cameroon and Panama,BIOTROPICA, Issue 1 2001Ulrich Hofer ABSTRACT Two tropical upland forests, Mount Kupe in Cameroon and Bosque Protector Palo Seco in Panama, were compared in terms of herpetofaunal species richness and density of individuals. Based on rarefaction, whereby samples are standardized for abundance, Palo Seco had significantly more species of frogs and lizards. Extrapolations to total local species richness, by fitting the Michaelis,Menten equation to the species accumulation curves and by using Chao's estimator, yielded divergent results: more lizard species on Mount Kupe, and an equal number of frogs at both sites. These disparities can be accounted for by differences in evenness, which was higher in Palo Seco. Frog density was significantly higher on Mount Kupe, snake density significantly higher in Palo Seco, and lizards exhibited no density difference. Overall, the results revealed a less consistent pattern and more moderate differences than what is known from southeast Asian,-Central American comparisons. This outcome is discussed in the light of available knowledge, but quantitative data from African forests are too sparse to allow general conclusions. Se comparó la herpetofauna de dos bosques tropicales húmedos ubicados en las montañas, Mount Kupe en Camerún y Bosque Protector Palo Seco en Panamá, en relación a la riqueza especifica y la densidad de individuos. Con base en el método de rarefacción, en el cual los muestreos se estandarizan en base a su abudancia, Palo Seco presenta significativamente mas especies de anuros y lagartos. Extrapolaciones con respecto a la riqueza especifica total de los sitios, mediante un ajuste de la ecuación de Michaelis-Menten a las curvas de acumulación de especies, y utilizando el índice de Chao, produjeron resultados divergentes: más especies de lagartos en Mount Kupe, y el mismo número de especies de anuros en ambos sitios. Dichas diferencias pueden resultar de una equitatividad más alta en Palo Seco. La densidad de anuros resultó significativamente más alta en Mount Kupe, mientras que la densidad de serpientes fue significativamente más alta en Palo Seco, y no se encontró una diferencia entre k densidad de lagartos en ambos sitios. En general los resultados muestran patrones menos consistentes y diferencias mis moderadas de las que se conocen entre el Sureste de Asia y Centroamerica. Se discuten los resultados con base en la información disponible, sin embargo, la existencia de datos cuantitativos para bosques africanos es demasiado escaza como para permitir conclusiones generales. RESUMES Se comparó la herpetofauna de dos bosques tropicales húmedos ubicados en las montañas, Mount Kupe en Camerún y Bosque Protector Palo Seco en Panamá, en relación a la riqueza especifica y la densidad de individuos. Con base en el método de rarefacción, en el cual los muestreos se estandarizan en base a su abudancia, Palo Seco presenta significativamente mas especies de anuros y lagartos. Extrapolaciones con respecto a la riqueza especifica total de los sitios, mediante un ajuste de la ecuación de Michaelis-Menten a las curvas de acumulación de especies, y utilizando el índice de Chao, produjeron resultados divergentes: más especies de lagartos en Mount Kupe, y el mismo número de especies de anuros en ambos sitios. Dichas diferencias pueden resultar de una equitatividad más alta en Palo Seco. La densidad de anuros resultó significativamente más alta en Mount Kupe, mientras que la densidad de serpientes fue significativamente más alta en Palo Seco, y no se encontró una diferencia entre k densidad de lagartos en ambos sitios. En general los resultados muestran patrones menos consistentes y diferencias mis moderadas de las que se conocen entre el Sureste de Asia y Centroamerica. Se discuten los resultados con base en la información disponible, sin embargo, la existencia de datos cuantitativos para bosques africanos es demasiado escaza como para permitir conclusiones generales. [source] | ||||||||||