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Weber MF Stover CA Gilbert LR Nevitt TJ Ouderkirk AJ 《Science (New York, N.Y.)》2000,287(5462):2451-2456
Multilayer mirrors that maintain or increase their reflectivity with increasing incidence angle can be constructed using polymers that exhibit large birefringence in their indices of refraction. The most important feature of these multilayer interference stacks is the index difference in the thickness direction (z axis) relative to the in-plane directions of the film. This z-axis refractive index difference provides a variable that determines the existence and value of the Brewster's angle at layer interfaces, and it controls both the interfacial Fresnel reflection coefficient and the phase relations that determine the optics of multilayer stacks. These films can yield optical results that are difficult or impossible to achieve with conventional multilayer optical designs. The materials and processes necessary to fabricate such films are amenable to large-scale manufacturing. 相似文献
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Prothrombin time and activated partial thromboplastin time using a point‐of‐care analyser (Abaxis VSpro®) in Bennett's wallabies (Macropus rufogriseus) 
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下载免费PDF全文 BN Nevitt SK Chinnadurai MK Watson JN Langan MJ Adkesson 《Australian veterinary journal》2016,94(10):384-386
There are few reports of coagulation times in marsupial species. Blood samples collected from 14 Bennett's wallabies (Macropus rufogriseus) under anaesthesia during routine health assessments were analysed for prothrombin time (PT) and activated partial thromboplastin time (aPTT) using a point‐of‐care analyser (POC) (Abaxis VSPro®). The wallabies had an aPTT mean of 78.09 s and median of 78.1 s. The PT for all wallabies was greater than 35 s, exceeding the longest time measured on the POC. Although PT was significantly longer, aPTT was similar to the manufacturer's domestic canine reference range. 相似文献
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大杜鹃(Cuculus canorus)通常寄生小型雀形目鸟类。由于杜鹃雏鸟的排他性拱卵或拱雏,导致宿主繁殖失败,因此宿主进化出如卵识别能力的反寄生策略。反过来,杜鹃也同时进化出如模拟宿主卵的寄生策略。于是两者之间的相互作用可形成类似军备竞赛的协同进化关系。在匈牙利,大苇莺(Acrocephalus arundinaceus)是大杜鹃的主要宿主,寄生率可高达约 40-65%。以往被认为是大苇莺一个亚种的东方大苇莺(A. orientalis)在日本的种群也被大杜鹃寄生(25-40%)。通过采用光纤光谱仪量化大杜鹃及其宿主的卵色特征,我们比较了东、西半球大杜鹃对两种苇莺的寄生模拟程度。鸟类视觉模型显示,对于可见光颜色,杜鹃与宿主之间卵色的模拟程度在匈牙利高于日本,但匈牙利杜鹃和宿主均较大的卵色变异程度可导致卵色模拟困难。杜鹃与苇莺卵色的量度差异在日本较低,这被证明是宿主拒卵行为的一个重要影响因素。苇莺对大杜鹃卵的拒绝率在日本(35%)和匈牙利(37%)相似。与匈牙利不同,在日本,宿主对杜鹃寄生的应对策略如拒卵行为,先于杜鹃的反适应对策。我们认为,两种近缘物种大苇莺对杜鹃寄生的不同反寄生行为,代表了协同进化军备竞赛的不同演化阶段。 相似文献
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Coral reefs resemble islands of productive habitats where fishes aggregate, forage, and spawn. Although it has been suggested that some reef fishes use biogenic chemicals as aggregation cues, specific chemicals have not been identified. Dimethylsulfoniopropionate (DMSP), a secondary metabolite of many marine algal species, is released during foraging by higher-order consumers. DMSP has been studied intensively for its role in oceanic sulfur cycles and global climate regulation, but its ecological importance to marine fishes is unknown. We present evidence that planktivorous reef fishes will aggregate to experimental deployments of DMSP over coral reef habitats in the wild. 相似文献
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Among birds, the Procellariiform seabirds (petrels, albatrosses, and shearwaters) are prime candidates for using chemical cues for individual recognition. These birds have an excellent olfactory sense, and a variety of species nest in burrows that they can recognize by smell. However, the nature of the olfactory signature--the scent that makes one burrow smell more like home than another--has not been established for any species. Here, we explore the use of intraspecific chemical cues in burrow recognition and present evidence for partner-specific odor recognition in a bird. 相似文献
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始建于16世纪初的拙政园是中国园林的杰出代表,建园之初,文徵明曾多次作有拙政园图。从文氏《王氏拙政园记》和《拙政园卅一图》探析明代拙政园的原貌,可以了解到明代江南文人园林设计的理想品质和＂虽由人作,宛如天开＂的深邃意境。对当代园林景观建设也有一定的借鉴意义。 相似文献
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Rajendran Duraisamy Ezhuthupurakkal Preedia Babu Lakshman Rithu Gowda Nisarani Kollurappa Shivakumar Manimaran Ayyasamy Rao Somu BN 《Veterinary research communications》2022,46(2):315-328
Veterinary Research Communications - Livestock plays a significant role in the socio-economic development of developing countries by providing livelihood and nutritional security, transport,... 相似文献
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