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The latitudinal decline of species richness is a general spatial pattern of biodiversity, and it applies to marine species as well. Based on a latitudinal gradient of marine species richness, potential stocks of marine ecosystem services are expected to be higher in lower latitudes through increment in biodiversity. However, little is known about the relationships of the marine ecosystem services with latitude and biodiversity. We estimated the latitudinal patterns and relationships with the biodiversity of potential stocks of three major reef fish-based ecosystem services (fisheries production, aquarium fish production, and recreational diving) at ten coral habitats from tropical to temperate zones in the Kuroshio Current region (8°37′N–33°24′N) using field survey data and information from relevant websites and administrative statistics. We found a latitudinal declin from south to north in potential stocks of aquarium fish production and diving in this region, whereas the peaks of fisheries production were found around both tropical and sub-tropical zones. Our results also showed strong positive effects of biodiversity on potential stocks of the three ecosystem services, highlighting the importance of conserving diverse fish species to sustain multiple services at high levels. Broad spatial patterns of the reef fish-based ecosystem services are useful as baselines for future evaluation of their changes. As the effects of climate change on reef fishes are predicted to vary among different latitude zones, our estimates of the ecosystem services infer specific management and economic actions for the respective zones against climate change.  相似文献   
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A low-pressure microwave-induced helium plasma serves as an excitation source for metal chlorides, nitrates, and sulfates vaporized from a filament, resulting in fractional vaporization and differential sensitivities of detection of the elements depending on the vapor pressures of their salts. The shapes of the single emission peaks, which are simple in the presence of potassium chloride, become complex and may double in number.  相似文献   
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Macroautophagy is a major degradation mechanism of cell components via the lysosome. Macroautophagy greatly contributes to not only cell homeostasis but also the prevention of various diseases. Because macroautophagy proceeds through multi-step reactions, researchers often face a persistent question of how macroautophagic activity can be measured correctly. To make a straightforward determination of macroautophagic activity, diverse monitoring assays have been developed. Direct measurement of lysosome-dependent degradation of radioisotopically labeled cell proteins has long been applied. Meanwhile, indirect monitoring procedures have been developed. In these assays, autophagosome marker proteins, microtubule-associated proteins 1A/1B light chain 3B-II (LC3B-II) and gamma-aminobutyric acid receptor-associated protein-II (GABARAP-II) have been analyzed and the validity of the assays strongly depends on appropriate assessment of the fluctuation of LC3-II and/or GABARAP-II levels in the presence or absence of lysosomal inhibitors. This article describes these monitoring methods, paying special attention to the principles and characteristics of each procedure.  相似文献   
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Abstract Extraction of Streptococcus mutans with the detergents HECAMEG and lauroyl sarcosinate preferentially extracted antigen D, previously identified as a low molecular mass wall-associated protein. Western blotting with specific antisera was used to demonstrate that this antigen is the HPr component of the sugar-phosphotransferase transport system. Non-denaturing electrophoresis indicated that HECAMEG selectively extracted only one of the two forms of HPr. It is suggested that this form of HPr may have a specific cell surface location.  相似文献   
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Abstract A small cryptic plasmid, pRJF2, from Butyrivibrio fibrisolvens strain OB157 was isolated and sequenced. The plasmid is similar in organisation to the previously sequenced Butyrivibrio plasmid, pRJF1, with two open reading frames, ORF1 and ORF2, flanking a region tentatively identified as the replication origin, and a region of unknown function defined by terminal 79 bp invert repeats. The sequences of ORF1, ORF2, and the presumptive replication origin are highly conserved. The sequence between the 79 bp invert repeats is not, and is therefore presumed to be of lesser functional significance, although the 5' and 3' termini are still highly conserved. The functional importance for plasmid replication of these regions was tested by constructing potential shuttle vectors, each lacking one or more of the regions of interest. When the region between the invert repeats was deleted and replaced by the erythromycin resistance gene from pAM β1 together with pUC18, to produce the 7.9 kb chimaeric plasmid pYK4, the construct was successfully transformed into E. coli and B. fibrisolvens by electroporation, and was stably maintained in both hosts. Both ORF1 and ORF2 were required for successful transformation of B. fibrisolvens .  相似文献   
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1. 1. The study aimed at knowing whether thermal sensation during afternoon cool exposure could be influenced by bright light (4000 lx) or dim light (200 lx) in the forenoon.
2. 2. The subjects felt cooler after exposure to dim light than to bright light.
3. 3. Melatonin in the urine was significantly higher in bright light than in dim light at 10:30 h and at noon.
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We analysed the effects of Quercus crispula acorn abundance on the density dependence of the large Japanese wood mouse Apodemus speciosus using time series data (1992–2007). The data were obtained in a forest in northern Hokkaido, Japan, by live-trapping rodents and directly counting acorns on the ground. Acorn abundance in one year clearly influenced the abundance of wood mice in the following year in all models examined based on the Gompertz and Ricker model; in addition, the abundance of wood mice had effects on the population. Acorn abundance influenced the strength of density dependence (intraspecific competition) of the wood mouse population. When the abundance of acorns was high, density dependence was relaxed, and as a result the equilibrium density at which the population growth rate decreased to zero became higher. Those effects of acorn abundance were regarded as a nonlinear perturbation effect (sensu Royama 1992). The nonlinearity of density dependence was also detected; higher densities had stronger effects on population growth rates. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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