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Spatial variability can confound accurate estimates of catch per unit effort (CPUE), especially in highly migratory species. The incorporation of spatial structure into fishery stock assessment models should ultimately improve forecasts of stock biomass. Here, we describe a nonlinear time series model for producing spatially explicit forecasts of CPUE that does not require ancillary environmental or demographic data, or specification of a model functional form. We demonstrate this method using spatially resolved (1° × 1° cells) CPUE time series of North Pacific albacore in the California Current System. The spatial model is highly significant (P < 0.00001) and outperforms two spatial null models. We then create a spatial forecast map for years beyond the range of data. Such approaches can guide spatial management of resources and provide a complement to more data‐intensive, highly parameterized population dynamics and ecosystem models currently in use.  相似文献   
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Staphylococci were found in the tonsils of 121 (75.2%) of 161 cattle. There were 15 different species, 10 belonging to novobiocin-sensitive species. The most predominant species was S. simulans (79.3% of the 121 carriers), followed by S. aureus (20.7%), S. chromogenes (10.7%) and S. epidermidis (8.3%). The other 11 species were present in 0.8 to 5.8%. Twenty-six unidentifiable isolates were isolated from 26 (21.5%) carriers. Sixty-two (51.2%) of the 121 carriers yielded two to five Staphylococcus species together while only one species could be found in each of the other 59 (48.8%). Combinations of S. simulans and other species were most frequently encountered in 50 (41.3%) of the 121 carriers. Twenty-four (96.0%) out of 25 S. aureus isolates, 3 (42.9%) of 7 S. hyicus isolates and 45 (25.4%) of 177 coagulase-negative staphylococci (13 species and unidentifiable isolates) isolates were phage typable. Most of S. aureus isolates were lysed by bovine phages 119 (n = 16) or 116 (n = 5). Thirty-three (25.4%) of 45 coagulase-negative staphylococci typable isolates with Pulverer's phage set showed the phage pattern ph5/ph9/ph10/ph12/ph13/U4/U14/U16/++ +U20/U46. The tonsils of cattle thus appear to be a suitable environment for Staphylococcus species, particularly novobiocin-sensitive species.  相似文献   
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The present study was designed to determine the positive effects of artificial illumination on the juvenile black seabream, Acanthopagrus schlegeli , by comparing stomach contents and growth between juveniles exposed to light and those maintained in the absence of light. The major prey items for juvenile black seabream reared in illuminated cages were amphipods (IRI%=50.5), copepods (IRI%=44.7) and polychaetes (IRI%=3.0), whereas those for the juveniles maintained in unilluminated cages were copepods (IRI%=96.0), amphipods (IRI%=3.4) and polychaetes (IRI%=0.6). The specific growth rates (SGR) of the juveniles reared in illuminated cages (0.99%) were significantly higher than those of the juveniles maintained in unilluminated cages (0.78%).  相似文献   
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To elucidate the functional roles of PR10 genes from two pepper species during plant-pathogen interactions, PR10 genes were isolated from fungal-resistant (Capsicum baccatum var. PBC80) and fungal-susceptible (C. annuum var. Yeoju) pepper fruits infected with anthracnose fungus (Colletotrichum acutatum). Despite strong nucleotide sequence identity, there were significant differences in the patterns of gene expression and protein accumulation between the genes from the two host species. Induced expression of the PR10 mRNA in PBC80 (bacPR10) was highly maintained from 24 h after infection (HAI) rather than that in Yeoju (annPR10). These mRNA expression patterns were correlated with the level of respective protein that was detected as two or three bands in each species. Substantial induction of bacPR10 proteins was confirmed by 2D-gel analysis followed by immunoblotting. Immunolocalization study showed that deposition of bacPR10 was exclusively observed in the pericarp of PBC80 fruits after fungal infection, suggesting functional significance in defence. Additionally, in vitro analysis of the enzymatic properties of PR10 proteins revealed that recombinant bacPR10 had higher ribonucleolytic activity and exhibited less sensitivity to proteinase treatment than did annPR10. Taken together, these results support the idea that relative abundance and prolonged longevity of bacPR10 in PBC80 fruits may contribute to their increased resistance in response to the anthracnose fungus, as compared with Yeoju fruit.  相似文献   
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ABSTRACT It has been speculated that the N-terminal half of the readthrough domain (RTD) encoded by open reading frame 5 of Soybean dwarf virus (SbDV) is related to the vector specificity. To further investigate this hypothesis, transmissibility via aphids was tested on 17 SbDV isolates and comparisons of the deduced amino acid sequences of the coat protein (CP) and other proteins encoded by the RTD were made between these isolates. Isolates were distinguished into four strains: YS, causing yellowing in soybean and transmittable by Aulacorthum solani; DS, causing dwarfing and transmittable by A. solani; YP, causing yellowing and transmittable by Acyrthosiphon pisum; and DP, causing dwarfing and transmittable by A. pisum. Phylogenetic analysis showed that the trees for the CP and the C-terminal half of the RTD sequences contained clusters of isolates of the same symptom type, whereas the tree for the N-terminal half of the RTD contained clusters of isolates of the same aphid vector type. These results agreed with our previous data of the complete nucleotide sequences of four SbDV isolates, and strongly indicated a close relationship between the N-terminal half of the RTD amino acid sequences and aphid transmission specificity of SbDV.  相似文献   
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When dielectric materials are brought into contact and then separated, they develop static electricity. For centuries, it has been assumed that such contact charging derives from the spatially homogeneous material properties (along the material's surface) and that within a given pair of materials, one charges uniformly positively and the other negatively. We demonstrate that this picture of contact charging is incorrect. Whereas each contact-electrified piece develops a net charge of either positive or negative polarity, each surface supports a random "mosaic" of oppositely charged regions of nanoscopic dimensions. These mosaics of surface charge have the same topological characteristics for different types of electrified dielectrics and accommodate significantly more charge per unit area than previously thought.  相似文献   
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1. Phosphate solution, prostaglandin F2alpha and E2, arachidonic acid and arginine vasotocin were injected intrauterinely or intravenously into laying quail hens 6 h before expected oviposition. Following injections, induced ovipositions and secretions of pigment from their shell glands were observed. 2. The effects of intrauterine injection with prostaglandins, which induced oviposition and pigment secretion, were not inhibited by pre-injection of indomethacin. 3. Indomethacin completely inhibited the inducing effects on oviposition and pigment secretion of intrauterine injections with phosphate solution and arachidonic acid. 4. Intravenous injection with arginine vasotocin or prostaglandins also induced oviposition and pigment secretion; indomethacin, however, only inhibited pigment secretion. 5. It is concluded that the effects of prostaglandins on pigment secretion from the shell gland were demonstrated experimentally.  相似文献   
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