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71.
Food and Environmental Virology - This study investigated the influence of viral interference on the detection of enteric viruses using the integrated cell culture (ICC)-PCR with a BGM cell line....  相似文献   
72.
In the Indo-Pacific area, the Caribbean region and West Africa, insular systems are colonised by particular Gobiids of the Sicydiinae subfamily. These species spawn in freshwater, the free embryos drift downstream to the sea where they undergo a planktonic phase, before returning to rivers to grow and reproduce; an amphidromous lifestyle. These gobies are the biggest contributors to the diversity of fish communities in insular systems and have the highest levels of endemism, yet their phylogeny has not been explored before with molecular data. To understand the phylogeny and the biogeography of this subfamily, sequences from the mitochondrial 16S rDNA and cytochrome oxidase I and from the nuclear rhodopsin gene were obtained for 50 Sicydiinae specimens of seven genera. Our results support the monophyly of the subfamily and of all the genera except Sicyopus, which is polyphyletic. Five major clades were identified within this subfamily. One clade clusters Sicyopterus and Sicydium as sister genera, one contains the genus Stiphodon split into two different groups, two other clades include only Sicyopus (Smilosicyopus) and Cotylopus, respectively, and the last clade groups Akihito, Lentipes and Sicyopus (Sicyopus). As a result, the subgenus Smilosicyopus is elevated herein as a genus. A molecular dating approach helps the interpretation of these phylogenetic results in terms of amphidromy and biogeographical events that have allowed the Sicydiinae to colonise the Indo-Pacific, West African and Caribbean islands.  相似文献   
73.
Virgin female cabbage butterflies, Pieris rapae crucivora, accept and mate with courting males, whereas mated females reject them and assume the “mate refusal posture”. This study tested whether the biogenic amines, serotonin (5HT), dopamine (DA), and octopamine (OA), were responsible for this change in behavior. The results showed that 2–3-day-old virgin females fed with 5HT rejected courting males significantly more frequently compared with controls fed on sucrose. In contrast, the proportions of courting males rejected by virgin females fed with either DA or OA did not differ from sucrose-fed controls. Oral application of each amine resulted in significantly increased levels of the amine applied (or its metabolite) in the brain. The results strongly suggest that 5HT or a 5HT metabolite may be responsible for the post-mating change in behavioral response of 2–3-day-old virgin females to courting males. Similar effects of 5HT treatment were observed in 6–8-day-old virgin females, but in this case the results were only marginally different from the controls, suggesting that the effect may decline with increasing female age.  相似文献   
74.
Investigations were performed on the selective non-catalytic reduction (SNCR) of nitric oxide (NO) at TAMARA, the pilot-scale waste incineration plant of the Karlsruhe Research Center. Aqueous ammonia (NH3) was injected into the combustion chamber as reductant. The influence of NH3 on various inorganic and organic compounds in the flue gas was investigated. The concentrations of NO were reduced by up to about 90% by NH3 injection. The concentrations of most of the other inorganic and organic compounds, including in particular PCDD and PCDF, did not change significantly.  相似文献   
75.
Combustion of brominated flame retardants and behavior of its byproducts   总被引:13,自引:0,他引:13  
The substance flow rate of PBDDs/DFs into flue gas and incineration residues from incineration of three types of waste samples containing brominated flame retardants were examined. The samples used consisted of PBDEs (a typical retardant), used TV casing materials (actual waste materials), and waste printed circuit boards. PBDDs/DFs concentrations in the experimental samples of PBDEs/PE, waste TV casing materials and printed circuit boards ranged between 3000 and 130,000 ng/g. These values are very high when compared to other investigations. The increase of chlorine concentration in input sample reduced the ratio of PBDDs/DFs in flue gas and raised the ratio of PCDDs/DFs. With adequate combustion control and flue gas treatment, the amount of PBDDs/DFs released from the incineration of resin containing brominated flame retardants was lower than the input amount. The presence of PBDDs/DFs in incineration residues dominated the total amount of dioxins released. When PBDDs/DFs, PCDDs/DFs and PXDDs/DFs were considered as a total, the total amount released was lower than the total amount input.  相似文献   
76.
A simulation study was carried out to investigate simultaneously the effects of eco-physiological parameters on competitive asymmetry, self-thinning, stand biomass and NPP in a temperate forest using an atmosphere–vegetation dynamics interactive model (MINoSGI). In this study, we selected three eco-physiological relevant parameters as foliage profiles (i.e. vertical distribution of leaf area density) of individual trees (distribution pattern is described by the parameter η), biomass allocation pattern in individual tree growth (χ) and the maximum carboxylation velocity (Vmax). The position of the maximal leaf area density shifts upward in the canopy with increasing η. For scenarios with η < 4 (foliage concentrated in the lowest canopy layer) or η > 12 (foliage concentrated in the uppermost canopy layer), a low degree of competitive asymmetry was produced. These scenarios resulted in the survival of subordinate trees due to a brighter lower canopy environment when η < 4 or the generation of spatially separated foliage profiles between dominant and subordinate trees when η > 12. In contrast, competition between trees was most asymmetric when 4 ≤ η ≤ 12 (vertically widespread foliage profile in the canopy), especially when η = 8. In such cases, vertically widespread foliage of dominant trees lowered the opportunity of light acquisition for subordinate trees and reduced their carbon gain. The resulting reduction in carbon gain of subordinate trees yielded a higher degree of competitive asymmetry and ultimately higher mortality of subordinate trees. It was also shown that 4 ≤ η ≤ 12 generated higher self-thinning speed, smaller accumulated NPP, litter-fall and potential stand biomass as compared with the scenarios with η < 4 or η > 12. In contrast, our simulation revealed small effects of χ or Vmax on the above-mentioned variables as compared with those of η. In particular, it is notable that greater Vmax would not produce greater potential stand biomass and accumulated NPP although it has been thought that physiological parameters relevant to photosynthesis such as Vmax influence dynamic changes in forest stand biomass and NPP (e.g. the greater the Vmax, the greater the NPP). Overall, it is suggested that foliage profiles rather than biomass allocation or maximum carboxylation velocity greatly govern forest dynamics, stand biomass, NPP and litter-fall.  相似文献   
77.
The present study tested, in a non‐Western culture (Japan), the relative validity in predicting job satisfaction, life satisfaction, and happiness of core self‐evaluations (CSE), positive and negative affectivity (PA/NA), and the Neutral Objects Satisfaction Questionnaire (NOSQ). Consistent with previous results in primarily Western cultures, the four lower‐order traits that comprise CSE—self‐esteem, generalized self‐efficacy, locus of control, and neuroticism—indicated a higher‐order factor. While each lower‐order trait was itself related to the study's criteria, the CSE concept displayed in general, higher correlations with the dependent variables, and explained incremental variance in two of the study's three outcomes beyond PA, NA, and the NOSQ. These results indicate initial support for the generalizability of CSE in a culture that differs in many respects from Western cultures, and suggest that judgments of satisfaction and happiness in a non‐Western culture have a dispositional source. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
78.
Frolan A. Aya  Isao Kudo 《Marine Biology》2010,157(10):2157-2167
Use of stable isotope signatures to trace diet patterns in cultured marine bivalves, particularly when changing culture habitat, requires knowledge of the isotopic shift and enrichment between diet and consumer’s tissues. The aim of this study was to determine the patterns of isotope change and the variability of enrichment values (∆δ13C and ∆δ15N) in different tissues (muscle, gonad, digestive gland) of the Japanese scallop (Mizuhopecten yessoensis). It was hypothesized that the isotopic signatures of a consumer’s tissues changed during settlement and that the changes were related to variations in the isotopic signatures of food sources and gut contents. Particular attention was paid to the isotope enrichment between the diet and a consumer’s tissues using isotope analysis of gut content. Muscle δ15N values decreased significantly 3–5 months post-settlement in a nearshore seabed, concomitant with the ingestion of lower δ15N food. For juvenile scallops, sinking particles (SP) were considered a more important dietary source than suspended particulate organic matter (SPOM), based on the correspondence between SP and gut contents δ13C. Enrichment values (∆δ13C and ∆δ15N) varied with tissue and season. ∆δ15N was 2.4‰ in muscle, 1.2‰ in gonad, and 0.7‰ in the digestive gland. ∆δ13C was 3.2‰ in muscle, 2.3‰ in gonad, and −0.5‰ in the digestive gland. ∆δ15N was the lowest in summer (0.3‰), and ∆δ13C was the highest in autumn (2.8‰). ∆δ15N values were significantly influenced by age, but not ∆δ13C. Patterns of isotope ratios and enrichment values may be related to physiological attributes and differences in diet. This is the first study to demonstrate isotopic shift and enrichment encountered in different tissues of a cultured scallop when changing culture habitat.  相似文献   
79.
Evaporation rate of multi-component liquid such as motor gasoline is expected to change greatly with progress of evaporation because its composition changes. Therefore it is difficult to predict accurately amount of generated combustible vapor in the case that a multi-component liquid is spilt on a floor. Then, we assumed an evaporation model that composition of the vapor obeys the Raoult's law which considers the activity coefficient. Using the model, we calculated the vapor composition, the vapor pressure and the evaporation rate of the liquid. Then, comparison was done between the calculated values and the measured values obtained in this study. “Weight loss fraction” was used as a parameter signifying the progress of evaporation. The variations of the evaporation property were accurately predicted by the model. We derived a prediction model of the amount of generated combustible vapor from the relation between weight loss fraction and evaporation rate. It was found that the amount of generated vapor was expressed as a logarithmic function of time in case of a five-component liquid. Furthermore, we showed that the predicted flash point of a liquid using the composition obtained from the model was in good agreement with an experimental result.  相似文献   
80.
We developed a method to analyze atmospheric SO(x) (particulate SO(4)(2-)+ gaseous SO(2)) and NO(x) (NO + NO(2)) simultaneously using a battery-operated portable filter pack sampler. NO(x) determination using a filter pack method is new. SO(x) and NO(x) were collected on a Na(2)CO(3) filter and PTIO (2-phenyl-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl) + TEA (triethanolamine) filters (6 piled sheets), respectively. Aqueous solutions were then used to extract pollutants trapped by the filters and the resulting extracts were pre-cleaned (e.g. elimination of PTIO) and analyzed for sulfate and nitrite by ion chromatography. Recoveries of SO(2) and NO(x) from standard pollutant gases and consistency of the field data with those from other instrumental methods were examined to evaluate our method. SO(x) and NO(x) could be analyzed accurately with determination limits of 0.2 ppbv and 1.0 ppbv (as daily average concentrations), respectively. The sampler can determine SO(x) and NO(x) concentrations at mountainous or remote sites without needing an electric power supply.  相似文献   
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