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Long‐haul transportation demand is predicted to increase in the future, resulting in higher carbon dioxide emissions. Different drivetrain technologies, such as hybrid or battery electric vehicles, electrified roads, liquefied natural gas and hydrogen, might offer solutions to this problem. To assess their ecological and economic impact, these concepts were simulated including a weight and cost model to estimate the total cost of ownership. An evolutionary algorithm optimizes each vehicle to find a concept specific optimal solution. A model calculates the minimum investment in infrastructure required to meet the energy demand for each concept. A well‐to‐wheel analysis takes into account upstream and on‐road carbon dioxide emissions, to compare fully electric vehicles with conventional combustion engines. Investment in new infrastructure is the biggest drawback of electrified road concepts, although they offer low CO2 emissions. The diesel hybrid is the best compromise between carbon reduction and costs. 相似文献
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The male Laneella perisi (Mariluis) n. comb. is described based on specimens collected in the Cordillera Oriental (1,370–1,450 m asl), Florencia-Suaza, Caquetá, Colombia. A key to separate the two species of the genus Laneella and illustrations of the male genitalia and female abdomen, terminalia, and spermatheca are also presented. 相似文献
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Here we describe a pathological osteoderm from the crocodylomorph Diplocynodon hantoniensis (Bouldnor Formation, earliest Oligocene, Isle of Wight, United Kingdom). The specimen bears a porous, erosive branching channel that distorts the surface ornamentation and periosteum over 60% of the preserved dorsal surface area. We diagnose this condition as necrotizing dermatitis: a surficial bacterial or fungal infection that can penetrate the dermal layers to affect the underlaying penosteum of osteoderms. This condition has been previously reported for an extant tortoise and caiman; however, this is the first reported occurrence in the fossil record. 相似文献
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Alison M. Strack Ester Carballo-Jane Sheng-ping Wang Jiyan Xue Xiaoli Ping Lesley Ann McNamara Anil Thankappan Olga Price Michael Wolff T. J. Wu Douglas Kawka Michele Mariano Charlotte Burton Ching H. Chang Jing Chen John Menke Silvi Luell Emanuel I. Zycband Xinchun Tong Richard Raubertas Carl P. Sparrow Brian Hubbard John Woods Gary O'Neill M. Gerard Waters Ayesha Sitlani 《Journal of lipid research》2013,54(1):177-188
The use of nicotinic acid to treat dyslipidemia is limited by induction of a “flushing” response, mediated in part by the interaction of prostaglandin D2 (PGD2) with its G-protein coupled receptor, DP1 (Ptgdr). The impact of DP1 blockade (genetic or pharmacologic) was assessed in experimental murine models of atherosclerosis. In Ptgdr−/−ApoE−/− mice versus ApoE−/− mice, both fed a high-fat diet, aortic cholesterol content was modestly higher (1.3- to 1.5-fold, P < 0.05) in Ptgdr−/−ApoE−/− mice at 16 and 24 weeks of age, but not at 32 weeks. In multiple ApoE−/− mouse studies, a DP1-specific antagonist, L-655, generally had a neutral to beneficial effect on aortic lipids in the presence or absence of nicotinic acid treatment. In a separate study, a modest increase in some atherosclerotic measures was observed with L-655 treatment in Ldlr−/− mice fed a high-fat diet for 8 weeks; however, this effect was not sustained for 16 or 24 weeks. In the same study, treatment with nicotinic acid alone generally decreased plasma and/or aortic lipids, and addition of L-655 did not negate those beneficial effects. These studies demonstrate that inhibition of DP1, with or without nicotinic acid treatment, does not lead to consistent or sustained effects on plaque burden in mouse atherosclerotic models. 相似文献
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Schistosomiasis vector snails are subjected to extreme seasonal changes, particularly in ephemeral rivers and lentic waterbodies. In the tropics, aestivation is one of the adaptive strategies for survival and is used by snails in times of extremely high temperatures and desiccation. Aestivation therefore plays an important role in maintaining the transmission of schistosomiasis. This review assesses the possible impacts of climate change on the temporal and spatial distribution of schistosomiasis-transmitting snails with special emphasis on aestivation, and discusses the effect of schistosome infection on aestivation ability. The impacts of parasite development on snails, as well as physiological changes, are discussed with reference to schistosomiasis transmission. This review shows that schistosome-infected snails have lower survival rates during aestivation, and that those that survive manage to get rid of the infection. In general, snail aestivation ability is poor and survival chances diminish with time. Longer dry periods result in fewer, as well as uninfected, snails. However, the ability of the surviving snails to repopulate the habitats is high. 相似文献