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101.
正使用精品茶的好处多年来,亚洲文化在饮茶领域都扮演着重要角色,随着近些年开瓶即饮(RTD)饮料市场的加速发展,市场竞争日趋激烈,可供选择的茶或豆奶饮料越来越多,进而取代了往日碳酸饮料的地位。创造你的专属精品茶饮料(STB),将帮助你打造你的个人风格,传递出你的品牌信息。同时,  相似文献   
102.
Reliable niche models are a cornerstone of pest risk analyses, informing biosecurity policies and the management of biological invasions. Because species can invade and establish in areas with climates that are different from those that are found in their native range, it is important to accurately capture the range-limiting mechanisms in models that project climate suitability. We examined a published niche model for the beet armyworm, Spodoptera exigua, to assess its suitability for bioeconomic analyses of its pest threat, and identified issues with the model that rendered it unreliable for this purpose. Consequently, we refitted the CLIMEX model, paying close attention to the biology underpinning the stress mechanisms. This highlighted the necessity of carefully considering how the different stress mechanisms operate, and to select mechanisms which align with knowledge on the species’ biology. We also identified the important role of irrigation in modifying habitat suitability. The refitted model accords with both distribution data and our understanding of the biology of this species, including its seasonal range dynamics. The new model identifies establishment risks to South America, Africa, the Middle East and Asia, and highlights that under current climate, Europe is only climatically suitable during warm seasons when crops are available. The modelling exercise reinforced the importance of understanding the meaning of a location record (e.g. persistent versus ephemeral populations) and of carefully exploring the role of habitat-modifying factors, such as irrigation, in allowing species to persist in otherwise inclement localities.  相似文献   
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Neighboring genes are often coordinately expressed within cis-regulatory modules, but evidence that nonparalogous genes share functions in mammals is lacking. Here, we report that mutation of either TMEM138 or TMEM216 causes a phenotypically indistinguishable human ciliopathy, Joubert syndrome. Despite a lack of sequence homology, the genes are aligned in a head-to-tail configuration and joined by chromosomal rearrangement at the amphibian-to-reptile evolutionary transition. Expression of the two genes is mediated by a conserved regulatory element in the noncoding intergenic region. Coordinated expression is important for their interdependent cellular role in vesicular transport to primary cilia. Hence, during vertebrate evolution of genes involved in ciliogenesis, nonparalogous genes were arranged to a functional gene cluster with shared regulatory elements.  相似文献   
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Haemophilus parasuis infection in pigs is characterized by fibrinous polyserositis, arthritis and meningitis. Despite the fact that traditional diagnosis is based on herd history, clinical signs, bacterial isolation and serotyping, molecular-based methods are alternatives for species-specific tests and epidemiological studies. The aim of this study was to characterize H. parasuis field strains from different states of Brazil, employing serotyping and genotyping methods. Serotyping revealed that serovar 4 was the most prevalent (26.1%), followed by serovars 5 (17.4%), 14 (8.7%), 13 (4.4%) and 2 (4.4%), whereas 39% of the strains were considered as untypeable. AFLP with a single enzyme and PFGE were able to type all isolates tested, generating 34 and 20 different profiles, respectively, including untypeable strains. Besides the slightly higher discrimination index presented by AFLP, PFGE with Not I restriction enzyme showed a better correlation with epidemiological data, grouping strains of the same serovar, animal or farm origin. The results indicated AFLP and PFGE as valuable tools for typing H. parasuis isolates collected in Brazil.  相似文献   
105.
Although dilution of lake water has been used for improvement of water quality and algal blooms control, it has not necessarily succeeded to suppress the blooms. We hypothesized that the disappearance of algal blooms by dilution could be explained by flow regime, nutrient concentrations, and their interaction. This study investigated the effects of daily renewal rate (d), nitrogen (N) and phosphorus (P) concentration, and their interaction on the domination between Microcystis aeruginosa and Cyclotella sp. through a monoxenic culture experiment. The simulation model as functions of the N:P mass ratio and dilution rate (D) (calculated from d) was constructed, and the dominant characteristics of both species were predicted based on the model using parameters obtained in a monoculture experiment and our previous study. Results of monoxenic culture experiment revealed that M. aeruginosa dominated in all conditions (d = 5 or 15%; N = 1.0 or 2.5 or 5.0 mg-N L?1; P = 0.1 or 0.5 mg-P L?1) and the predicted cell densities were substantially correspondent to experimental data. Under various N:P ratios and D values, characteristics of domination for each species were predicted, indicating that Cyclotella sp. tended to be dominant under high P concentrations (P ≥ 0.36 mg-P L?1) when the N:P ratio was less than 7.0, and M. aeruginosa could not form algal blooms at the N:P ratio ≤ 7.0 (N ≤ 0.7 mg-N L?1). It was also suggested that the dilution rate leading to the Cyclotella sp. domination required 0.20 day?1 or higher regardless of the N:P ratios.
Graphical Abstract ? M. aeruginosa and Cyclotella sp. could be a superior competitor in nutrient-limited and nutrient-rich conditions, respectively. ? The simulation model in this study indicated that the predicted cell density and nutrient concentration were substantially correspondent to experimental data. ? The model predicted that Cyclotella sp. tended to be dominant at the P ≥ 0.36 mg-P L?1 when the N:P ratio was less than 7.0, and M. aeruginosa could not form algal blooms at the N:P ratio ≤ 7.0 (N ≤ 0.7 mg-N L?1).
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106.
In this study, we describe an abnormal ectopically mineralized structure (EMS) that was found inside the skull of a juvenile Sparus aurata that also showed a bilateral opercular deformation. The overall phenotype and tissue composition were studied using micro‐CT scanning and histological analyses. The ectopic structure occupies a large volume of the brain cavity, partially extruding into the gill cavity. It shows a dense mineralization and an extracellular matrix‐rich phenotype, with variation in both the morphology and size of the cell lacunae, combined with an irregular fibre organization inside the matrix. This study is the first to report such an EMS in a juvenile teleost fish, where the tissue does not resemble any other connective tissue type described in bony fish so far. The tissue phenotype seems to rule out that the EMS corresponds to a tumorous cartilage. Yet, it is rather reminiscent of a highly mineralized structure found in cartilaginous fish, where it is suggested to be associated with damage repair.  相似文献   
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The success of penaeid shrimp aquaculture has been limited by endemic and epidemic infectious diseases around the world and shrimp defense mechanisms are a priority for control, prevention, and diagnosis. The lethal dose (LD50) of Escherichia coli lipopolysaccharides was calculated and pathogen injection and dissolved ammonia concentration on immune response were evaluated in southern white shrimp Litopenaeus schmitti. The lethal dose of lipopolysacharides was 3.78 mg kg− 1 body weight. Injection caused changes in phenoloxidase activity in plasma and nitric oxide and total haemocyte counts within the first 24 h. High concentration of dissolved ammonia caused a decrease in haemocytes by 66% within the first 72 h, when compared to the control. Hemagglutination in plasma was not affected by injection or high concentrations of dissolved ammonia. The results showed that white shrimp recognized the lipopolysacharides and responded to this microbial elicitor, as indicated by a variety of immunological indicators and that increased dissolved ammonia affected the number of circulating haemocytes.  相似文献   
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