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Comment on: Rokavec M, et al. Mol Cell 2012; 45:777-89.  相似文献   
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Due to the fact that the flood data series of small drainage basins is relatively short, available data are often not sufficient for flood risk analysis. This presents the problem of risk analysis using very small data samples. One method that can be applied is to regard the available small samples as fuzzy information and optimize them using information diffusion technology to yield analytical results with greater reliability. In this article a risk analysis method based on information diffusion theory is applied to create a new flood risk analysis model. Application of the model is illustrated taking the Jinhuajiang and Qujiang drainage basins as examples. This is a new attempt at applying information diffusion theory in flood risk analysis. Computations based on this analytical flood risk model can yield an estimated flood damage value that is relatively accurate. This study indicates that the aforementioned model exhibits fairly stable analytical results, even when using a small set of sample data. The results also indicate that information diffusion technology is highly capable of extracting useful information and therefore improves system recognition accuracy. This method can be easily applied and the analytical results produced are easy to understand. Results are accurate enough to act as a guide in disaster situations.  相似文献   
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In total, 366 birds representing 55 species in 24 families and eight orders, were examined for chewing lice (Phthiraptera: Amblycera, Ischnocera) in two high‐altitude localities in Yunnan Province, China. In Ailaoshan, almost all of the birds examined were resident passeriforms, of which 36% were parasitized by chewing lice. In Jinshanyakou, most birds were on migration, and included both passerine and non‐passerine birds. Of the passerine birds caught in Jinshanyakou, only one bird (0.7%) was parasitized by chewing lice. The prevalence of Myrsidea and Brueelia‐complex lice on birds caught in Ailaoshan was higher than in previous reports. Of the chewing lice identifiable to species level, three represent new records for China: Actornithophilus hoplopteri (Mjöberg, 1910), Maculinirmus ljosalfar Gustafsson & Bush, 2017 and Quadraceps sinensis Timmermann, 1954. In total, 17 new host records are included, of which we describe two as new species in the Brueelia‐complex: Guimaraesiella (Cicchinella) ailaoshanensis sp. nov. ex Schoeniparus dubius dubius (Hume, 1874) and G. (C.) montisodalis sp. nov. ex Fulvetta manipurensis tonkinensis Delacour & Jabouille, 1930. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:9FC3D8EE‐2CED‐4DBE‐A1DB‐471B71260D27 .  相似文献   
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COVID-19, caused by SARS-CoV-2, is an acute and rapidly developing pandemic, which leads to a global health crisis. SARS-CoV-2 primarily attacks human alveoli and causes severe lung infection and damage. To better understand the molecular basis of this disease, we sought to characterize the responses of alveolar epithelium and its adjacent microvascular endothelium to viral infection under a co-culture system. SARS-CoV-2 infection caused massive virus replication and dramatic organelles remodeling in alveolar epithelial cells, alone. While, viral infection affected endothelial cells in an indirect manner, which was mediated by infected alveolar epithelium. Proteomics analysis and TEM examinations showed viral infection caused global proteomic modulations and marked ultrastructural changes in both epithelial cells and endothelial cells under the co-culture system. In particular, viral infection elicited global protein changes and structural reorganizations across many sub-cellular compartments in epithelial cells. Among the affected organelles, mitochondrion seems to be a primary target organelle. Besides, according to EM and proteomic results, we identified Daurisoline, a potent autophagy inhibitor, could inhibit virus replication effectively in host cells. Collectively, our study revealed an unrecognized cross-talk between epithelium and endothelium, which contributed to alveolar–capillary injury during SARS-CoV-2 infection. These new findings will expand our understanding of COVID-19 and may also be helpful for targeted drug development.Subject terms: Mechanisms of disease, Viral infection  相似文献   
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Cecropin XJ, as a heat stable antimicrobial peptide (AMP), displayed broad bacteriostatic activities, effectively inhibited proliferation of cancer cells and induced cell apoptosis in vitro. However, it exhibited little hemolytic activity and very low cytotoxicity to erythrocytes and normal cells. Although exerts multiple remarkable bioactivities, the refined molecular conformation of native Cecropin XJ remains unsolved. The aim of the present study is to comprehensively investigate the physicochemical characteristics and structure-function relationship of this antimicrobial peptide by using a series of bioinformatics and experimental approaches. In this study, we revealed that the mature Cecropin XJ consists of 41 amino acids, containing two α-helical structures from Lys7 to Lys25 and from Ala29 to Ile39. The phylogenetic tree indicated that Cecropin XJ belongs to the Class I AMPs of cecropin family. Hydrophobic analysis showed Cecropin XJ is a typical amphiphilic molecule. The surface of Cecropin XJ was found to have a much wide range of electrostatic potential from ?83.243 to +83.243. The amphipathicity and surface potential of Cecropin XJ partially supported the AMP pore-forming hypothesis. Scanning electron microscopy experimentally confirmed the damages of Cecropin XJ to microbial membrane. Four predicted docking sites respectively for magnesium ion (Mg2+), adenosine diphosphate (ADP), bacteriopheophytin (BPH), and guanosine triphosphate (GTP) were found on the surface of Cecropin XJ. Thereinto, Mg2+ was experimentally proved to suppress the antibacterial activity of Cecropin XJ; both GTP and ADP enhanced the bactericidal activities to varying degrees. The present study provides a foundation for further investigation of molecular evolution, structural modification, and functional mechanisms of Cecropin XJ.  相似文献   
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7-dehydrocholesterol (7-DHC) and cholesterol (CHOL) are biomarkers of Smith-Lemli-Opitz Syndrome (SLOS), a congenital autosomal recessive disorder characterized by elevated 7-DHC level in patients. Hair samples have been shown to have great diagnostic and research value, which has long been neglected in the SLOS field. In this study, we sought to investigate the feasibility of using hair for SLOS diagnosis. In the presence of antioxidants (2,6-ditert-butyl-4-methylphenol and triphenylphosphine), hair samples were completely pulverized and extracted by micro-pulverized extraction in alkaline solution or in n-hexane. After microwave-assisted derivatization with N,O-Bis(trimethylsilyl)trifluoroacetamide, the analytes were measured by GC-MS. We found that the limits of determination for 7-DHC and CHOL were 10 ng/mg and 8 ng/mg, respectively. In addition, good linearity was obtained in the range of 50–4000 ng/mg and 30–6000 ng/mg for 7-DHC and CHOL, respectively, which fully meets the requirement for SLOS diagnosis and related research. Finally, by applying the proposed method to real hair samples collected from 14 healthy infants and two suspected SLOS patients, we confirmed the feasibility of hair analysis as a diagnostic tool for SLOS. In conclusion, we present an optimized and validated analytical method for the simultaneous determination of two SLOS biomarkers using human hair.  相似文献   
8.
Addition of fertilizer amendments is regarded as an ideal approach to enhancing phytoextraction. However, there is little information available on the influence of common fertilizers on Cd accumulation of two newly reported Cd accumulators, Cosmos sulphureus and Cosmos bipinnata (C. sulphureus and C. bipinnata). The effects of N (CO(NH2)2), NP (CO(NH2)2 + Ca(H2PO4)2), and NPK (CO(NH2)2 + Ca(H2PO4)2 + KCl) fertilizers on Cd accumulation and subcellular distribution of C. sulphureus and C. bipinnata were studied in a 70-d pot experiment. The results showed that Cd uptake of C. sulphureus and C. bipinnata with NPK fertilizer was significantly higher than control, N, and NP fertilizers, especially 3.8- and 4.7-fold higher than control (p < 0.05). Compared with C. bipinnata, C. sulphureus achieved higher biomass and Cd uptake in aboveground parts under fertilizer treatments, especially NPK fertilizer. The Cd subcellular distribution revealed that segregation of Cd to Cd-rich granules (MRG) might play an important role in Cd detoxification in both species. C. sulphureus is more likely than C. bipinnata to separate the Cd in MRG and reduce the partition in the heat-denatured protein fraction, especially with NPK fertilizer. Therefore, C. sulphureus combined with NPK fertilizers could be an effective method to remediate Cd-polluted farmland soils in China.  相似文献   
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1. Larval success was compared when one, two, or three egg clutches were laid in kumquat fruits (≈ 10 ml in volume) either successively on the same day or at the rate of one clutch per day. 2. Increased clutch density was associated with a significant decrease in larval survival rate and non‐significant decreases in larval growth rate and pupal mass. 3. Larval and pupal parameters showed significantly larger variance when clutches were laid on successive days than on the same day, suggesting a competitive advantage for older larvae over younger larvae. 4. The results suggest that, in small fruit, reduced fitness due to larval competition may act against possible fitness benefits due to social facilitation among adult females, hence reducing the likelihood of non‐linear population dynamics caused by processes such as the Allee effect.  相似文献   
10.
Many animals exhibit different behaviors in different seasons. The photoperiod can have effects on migration, breeding, fur growth, and other processes. The cyclic growth of the fur and feathers of some species of mammals and birds, respectively, is stimulated by the photoperiod as a result of hormone-dependent regulation of the nervous system. To further examine this phenomenon, we evaluated the Arbas Cashmere goat (Capra hircus), a species that is often used in this type of research. The goats were exposed to an experimentally controlled short photoperiod to study the regulation of cyclic cashmere growth. Exposure to a short photoperiod extended the anagen phase of the Cashmere goat hair follicle to increase cashmere production. Assessments of tissue sections indicated that the short photoperiod significantly induced cashmere growth. This conclusion was supported by a comparison of the differences in gene expression between the short photoperiod and natural conditions using gene chip technology. Using the gene chip data, we identified genes that showed altered expression under the short photoperiod compared to natural conditions, and these genes were found to be involved in the biological processes of hair follicle growth, structural composition of the hair follicle, and the morphogenesis of the surrounding skin appendages. Knowledge about differences in the expression of these genes as well as their functions and periodic regulation patterns increases our understanding of Cashmere goat hair follicle growth. This study also provides preliminary data that may be useful for the development of an artificial method to improve cashmere production by controlling the light cycle, which has practical significance for livestock breeding.  相似文献   
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