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1.
The effect of various constant temperatures on survival, development and adult longevity of Sesamia nonagrioides Lefébvre (Lepidoptera: Noctuidae) was studied under laboratory conditions. The following temperatures were tested: 14, 17, 21, 25 and 31 °C. The percentage of individuals that completed development at each temperature as well as the days needed for the emergence of the pupa and adult eclosion were measured. Adult longevity was estimated under the same conditions. Development time decreased significantly with increasing temperature within the range 14–25 °C. Survival was higher at medium temperatures (17–25 °C) in comparison with that at more extreme temperature regimens (14 and 31 °C). Egg and first larval instars were the stages where S. nonagrioides suffered the highest mortality levels at all temperatures. The highest survival was recorded with experimental individuals aging between the third and fifth larval instar. Thermal requirements of development (developmental thresholds, thermal constant, optimum temperature) of S. nonagrioides were estimated with application of linear and one nonlinear models (Logan I). Upper and lower developmental thresholds ranged between 31.2 and 36.2 and 7.0 and 10.3 °C, respectively. The optimum temperature for development (where maximum rate of development occurs) was estimated at between 28.1 and 30.3 °C. The thermal constant for total development was estimated at 1,000.0 degree-days. Adult longevity was also affected by temperature, as it was significantly reduced at higher temperatures (21–31 °C) compared to the lower ones (14 and 17 °C). This information would be useful in determining the critical temperatures which may affect the distribution of S. nonagrioides concerning potential climate change.  相似文献   
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Influenza A viruses (IAVs) have both zoonotic and anthroponotic potential and are of public and veterinary importance. Swine are intermediate hosts and ‘mixing vessels’ for generating reassortants, progenies of which may harbour pandemic propensity. Swine handlers are at the highest risk of becoming infected with IAVs from swine but there is little information on the ecology of IAVs at the human–animal interface in Africa. We analysed and characterized nasal and throat swabs from swine and farmers respectively, for IAVs using RT‐qPCR, from swine farms in the Ashanti region, Ghana. Sera were also analysed for IAVs antibodies and serotyped using ELISA and HI assays. IAV was detected in 1.4% (n = 17/1,200) and 2.0% (n = 2/99) of swine and farmers samples, respectively. Viral subtypes H3N2 and H1N1pdm09 were found in human samples. All virus‐positive swine samples were subtyped as H1N1pdm09 phylogenetically clustering closely with H1N1pdm09 that circulated among humans during the study period. Phenotypic markers that confer sensitivity to Oseltamivir were found. Serological prevalence of IAVs in swine and farmers by ELISA was 3.2% (n = 38/1,200) and 18.2% (n = 18/99), respectively. Human H1N1pdm09 and H3N2 antibodies were found in both swine and farmers sera. Indigenous swine influenza A viruses and/or antibodies were not detected in swine or farmers samples. Majority (98%, n = 147/150) of farmers reported of not wearing surgical mask and few (4%, n = 6) reported to wear gloves when working. Most (n = 74, 87.7%) farmers reported of working on the farm when experiencing influenza‐like illness. Poor husbandry and biosafety practices of farmers could facilitate virus transmission across the human–swine interface. Farmers should be educated on the importance of good farm practices to mitigate influenza transmission at the human–animal interface.  相似文献   
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A 2-week-old female Thoroughbred foal was born with a firm, expansile, progressively enlarging mass involving the left hemimandible. Grossly, the mass was composed of variably sized cavernous spaces containing clotted blood and serofibrinous exudate, separated by fibrous and fibroosseous septa. Histologically, the spaces were lined by flattened to plump spindle cells and contained hemorrhage, fibrin, and multinucleated osteoclast-like cells. The septa separating adjacent cavernous spaces contained interlacing bundles and streams of spindle cells, multinucleated giant cells, hemosiderophages, mineral deposits, and spicules and trabeculae of reactive and poorly mineralized bone. A diagnosis of congenital aneurysmal bone cyst was made based on histologic features. The pathogenesis for the development of aneurysmal bone cysts is still undetermined, although spindle cells lining cavernous spaces in the foal exhibited negative immunolabeling for factor-VIII (F8) and positive immunolabeling for smooth muscle actin, suggesting vascular smooth muscle origin and possible blood flow disturbance.  相似文献   
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Human–wildlife conflict (HWC) is a significant and growing problem, with mitigation measures being increasingly dependent on sociopolitical landscapes. We surveyed 766 people from two Australian states to assess their understanding of shark attack mitigation measures. Although beach users were relatively aware of existing mitigation measures, the efficacy of aerial patrol was overestimated, as was the risk of shark attack. The latter, as well as the innate fear of shark attacks, is likely to explain the high level of worry related with shark attack and fits within the affect heuristic that can influence how people respond to risk situations. Beach users did not, however, choose beaches based on existing mitigation measures. Results highlight the need for improved education about the risks of shark attack and for further research into the emotional response from low probability–high consequences incidents.  相似文献   
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Cultured beef is a method where stem cells from skeletal muscle of cows are cultured in vitro to gain edible muscle tissue. For large-scale production of cultured beef, the culture technique needs to become more efficient than today’s 2-dimensional(2D) standard technique that was used to make the first cultured hamburger. Options for efficient large-scale production of stem cells are to culture cells on microcarriers, either in suspension or in a packed bed bioreactor, or to culture aggregated cells in suspension. We discuss the pros and cons of these systems as well as the possibilities to use the systems for tissue culture. Either of the production systems needs to be optimized to achieve an efficient production of cultured beef. It is anticipated that the optimization of large-scale cell culture as performed for other stem cells can be translated into successful protocols for bovine satellite cells resulting in resource and cost efficient cultured beef.  相似文献   
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Cultured beef is a method where stem cells from skeletal muscle of cows are cultured in vitro to gain edible muscle tissue. For large-scale production of cultured beef, the culture technique needs to become more efficient than today's 2-dimensional(2D) standard technique that was used to make the first cultured hamburger. Options for efficient large-scale production of stem cells are to culture cells on microcarriers, either in suspension or in a packed bed bioreactor, or to culture aggregated cells in suspension. We discuss the pros and cons of these systems as well as the possibilities to use the systems for tissue culture. Either of the production systems needs to be optimized to achieve an efficient production of cultured beef. It is anticipated that the optimization of large-scale cell culture as performed for other stem cells can be translated into successful protocols for bovine satellite cells resulting in resource and cost efficient cultured beef.  相似文献   
10.
Ash dieback (ADB) caused by the pathogen Hymenoscyphus fraxineus is the cause of massive mortality of Fraxinus spp. in Europe. The aim of this work was to check for the presence of the molecular marker for ADB tolerance in mapped healthy‐looking F. excelsior trees, and to compare its occurrence in trees exhibiting severe ADB symptoms. Monitoring of 135 healthy‐looking F. excelsior on the island of Gotland, Sweden, showed that after 3–4 years 99.3% of these trees had 0%–10% crown damage, thus remaining in a similar health condition as when first mapped. After 5–6 years, 94.7% of these trees had 0%–10% crown damage. Molecular analysis of leaf tissues from 40 of those showed the presence of the molecular marker in 34 (85.0%) trees, while it was absent in 6 (15.0%) trees. Analysis of leaf tissues from 40 severely ADB‐diseased trees showed the presence of the molecular marker in 17 (42.5%) trees, but its absence in 23 (57.5%) trees (p < .0001). The results demonstrated that monitoring of healthy‐looking F. excelsior is a simple and straightforward approach for the selection of presumably ADB‐tolerant ash for future breeding. The cDNA‐based molecular marker revealed moderate capacity on its own to discriminate between presumably ADB‐tolerant and susceptible F. excelsior genotypes.  相似文献   
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