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941.
Akrum H. Tamimi Sheri Carlino Sarah Edmonds Charles P. Gerba 《Food and environmental virology》2014,6(2):140-144
The objectives of this study were to determine the movement of a virus throughout a household and the impact of an alcohol-based hand sanitizer (ABHS) on reducing the movement and exposure of the virus to household members. Bacterial virus MS-2 was used as the surrogate for human enteric and respiratory viruses. Seven households with families having at least two children in the age range of 2–18 living in the home were used in this study. The hands of one adult family member were contaminated with 1 × 108. MS-2 bacteriophage in each home. After 8 h, the hands of each family member (10 fingers) and 20 frequently touched fomites were sampled to determine baseline contamination without intervention. Within 8 h, MS-2 was detected on all of the family member’s hands and most of the fomites. The intervention consisted of providing the families in all selected homes with bottles of an ABHS, which were placed in the kitchen, bathrooms, and nurseries. Smaller individual bottles were provided for each family member greater than 12 years old to place in purses, pockets, backpacks, etc. The families were instructed to use the ABHS one time or three times during the day. For one and three uses, a statistically significant reduction of virus on un-inoculated and inoculated hands of ~99 % occurred within 8 h. Similar reductions occurred on fomites throughout the households (97–99 %). These results demonstrate that the use of an ABHS can significantly reduce transfer of a virus to the hands, and to the commonly touched surfaces within the household. 相似文献
942.
943.
Kostas?SagonasEmail author Niki?Karambotsi Aristoula?Bletsa Aikaterini?Reppa Panayiotis?Pafilis Efstratios?D.?Valakos 《Die Naturwissenschaften》2017,104(3-4):22
In caudal autotomy, lizards shed their tail to escape from an attacking predator. Since the tail serves multiple functions, caudal regeneration is of pivotal importance. However, it is a demanding procedure that requires substantial energy and nutrients. Therefore, lizards have to increase energy income to fuel the extraordinary requirements of the regenerating tail. We presumed that autotomized lizards would adjust their digestion to acquire this additional energy. To clarify the effects of tail regeneration on digestion, we compared the digestive performance before autotomy, during regeneration, and after its completion. Tail regeneration indeed increased gut passage time but did not affect digestive performance in a uniform pattern: though protein income was maximized, lipid and sugar acquisition remained stable. This divergence in proteins may be attributed to their particular role in tail reconstruction, as they are the main building blocks for tissue formation. 相似文献
944.
Takuya?Kosumi Makio?TakedaEmail authorView authors OrcID profile 《Die Naturwissenschaften》2017,104(9-10):70
In temperate climates, the initiation and termination of diapause synchronize the stress-tolerant stage with the stressful season and reproduction with the non-stressful season in many insects. Synchronization is often regulated by photoperiodism.Voltinism and the ultimate size of adults are also important determinants for their lifecycle, and different diapause stages and voltinism patterns are known in crickets.Here, we investigated the life history of the African cricket Gryllus argenteus from Malawi, which is a typical arid tropical highland. The climate is characterized by alternating arid and wet seasons, each of which lasts for half a year, and where the available heat mass is much less than lowlands at the same latitude. We first measured the nymphal duration at each rearing temperature and calculated the lower developmental threshold (t 0) to be 20.19 °C based on Ikemoto and Takai (2000) and 19.38 °C based on a conventional line-fitting method. These values are very high relative to many other insects. The local temperature in winter does not fall below 15 °C, but this is much higher than the lethal limit. This suggested that critical stress in this locality was not coldness but low precipitation in winter. We estimated, based both on local temperature change and the Ikemoto and Takai’s t 0, that G. argenteus required 3 years to complete its lifecycle unlike wet lowland species, where univoltinism or multi-voltinism are commonplace. Photoperiodism was observed in this species, but due to a lag between annual cycles in photoperiod, temperature, and humidity, photoperiodism alone cannot atune their lifecycle with local conditions.Synchronization in this species was achieved by three different adaptations: photoperiodism, high t 0, and large body size, which give it a long lifecycle. Although the species cannot achieve a univoltine lifecycle because of its high t0 value, it can escape from dry season by entering diapause at moderate temperatures, probably thereby achieving adaptive synchrony of lifecycle with both favorable and unfavorable seasons. A comparison between a conventional photothermogram and a newly formulated photohydrogram or photohygrogram demonstrates that even though sufficient heat is available, scarcity of water and thus scarcity of foliage should force the cricket to maintain diapause at intermediate temperature. The results suggested that high t 0, large body size, and multi-ennial lifecycle mutually affect each other and formulate a unique adaptation under such an extreme environment. 相似文献
945.
Affirmative Action Programs (AAPs) are becoming increasingly common in the workplace. Typically their effectiveness has been assessed by the number of women and minorities hired and promoted. A neglected, but important measure of effectiveness is how AAPs are perceived by employees. When employees perceive that AAPs violate notions of fairness, negative attitudes and behaviors may occur and lead to decreased organizational performance. A model of perceived AAP fairness is presented using an organizational justice perspective. An initial (partial) test of the model is conducted and avenues for future research are discussed. 相似文献
946.
Nguyen Trang D T Kawai Kosuke Nakakubo Toyohiko 《Journal of Material Cycles and Waste Management》2023,25(1):302-313
Journal of Material Cycles and Waste Management - The accelerated generation of COVID-19 waste under the Delta-fuelled outbreak placed a sudden burden on waste disposal in Vietnam. To secure the... 相似文献
947.
Lunag Marcelino N. Abana Alexander S. Agcaoili Juco P. Arellano Jillien Kaith T. Caluza Coleen Angela G. Decena Nick Brylle V. Paz Emmanuel R. Dela Delgado Lyka Angela B. Obero Aaron F. Ocampo Don Miguel E. Sacdalan Charlene Ann D. 《Journal of Material Cycles and Waste Management》2023,25(2):1216-1226
Journal of Material Cycles and Waste Management - The daily use of facemask to prevent virus transmission increases the negative effect on the environment because of improper waste disposal. Due to... 相似文献
948.
Russian Journal of Ecology - A study of the anthropogenic impacts on the on-shore aggregation of true seals was carried out at a haul-out located at the mouth of Piltun Bay (the northeastern part... 相似文献
949.
Zadubrovskiy P. A. Vasina A. V. Novikova E. V. Kondratyuk E. Yu. Matskalo L. L. Novikov E. A. 《Russian Journal of Ecology》2021,52(4):283-289
Russian Journal of Ecology - To test the hypothesis that animals from habitats exposed to high anthropogenic pressure are more successful in adapting to captivity, immature narrow-skulled voles... 相似文献
950.
W.I. Ford J.F. Fox D.T. Mahoney G. DeGraves A. Erhardt S. Yost 《Journal of the American Water Resources Association》2020,56(4):692-711
In the Ohio River (OR), backwater confluence sedimentation dynamics are understudied, however, these river features are expected to be influential on the system’s ecological and economic function when integrated along the river’s length. In the following paper, we test the efficacy of organic and inorganic tracers for sediment fingerprinting in backwater confluences; we use fingerprinting results to evidence sediment dynamics controlling deposition patterns in confluences used for wetland and marina functions; and we quantify the spatial extent of tributary drainages with wetland and marina features in OR confluences. Both organic and inorganic tracers statistically differentiate sediment from stream and river end‐members. Carbon and nitrogen stable isotopes produce greater uncertainty in fingerprinting results than inorganic elemental tracers. Uncertainty analysis of the nonconservative tracer term in the organic matter fingerprinting application estimates an apparent enrichment of the carbon stable isotopes during instream residence, and the nonconservativeness is quantified with a statistical approach unique to the fingerprinting literature. Wetland and marina features in OR confluences impact 42% and 11% of tributary drainage areas, respectively. Sediment dynamics show wetland and marina confluences experience deposition from river backwaters with longitudinally linear and nonlinear patterns, respectively, from sediment sources. 相似文献