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121.
Allen's rule (1877) predicts ecogeographical anatomical variation in appendage proportions as a function of body temperature regulation. This phenomenon has been tested in a variety of animal species. In macaques, relative tail length (RTL) is one of the most frequently measured appendages to test Allen's rule. These studies have relied on museum specimens or the invasive and time-consuming capturing of free-ranging individuals. To augment sample size and lessen these logistical limitations, we designed and validated a novel noninvasive technique using digitalized photographs processed using LibreCAD, an open-source 2D-computer-aided design (CAD) application. This was used to generate pixelated measurements to calculate an RTL equivalent, the Tail to Trunk Index (TTI) = (tail [tail base to anterior tip] pixel count/trunk [neck to tail base] pixel count). The TTI of 259 adult free-ranging toque macaques (Macaca sinica) from 36 locations between 7 and 2,087 m above sea level (m.a.s.l.) was used in the analysis. Samples were collected from all three putative subspecies (M. s. sinica, aurifrons, and opisthomelas), at locations representing all altitudinal climatic zones where they are naturally distributed. These data were used to test whether toque macaque tail length variation across elevation follows Allen's rule, predicting that RTL decreases with increasing elevation and lower temperature. Our results strongly supported this prediction. There was also a statistically significant, negative correlation between elevation and annual average temperature. The best predictor for the TTI index was elevation. Significant subspecies differences in RTL are linked in part to their ecological and altitudinal niche separation, but overall the variation is seen as the species' adaptation to climate. The method developed for the quick morphometric assessment of relative body proportions, applicable for use on unhabituated free-ranging animals, widens the range of materials available for research studying morphological characteristics and their evolution in primates.  相似文献   
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Sm3+ ions doped strontium lithium lead borate glasses (SLLB:Sm) were prepared using a conventional melt‐quenching technique. The glasses were analyzed using X‐ray diffractometry and Fourier transform infrared spectroscopy, optical absorption, fluorescence spectral analysis, and fluorescence lifetime decay. The Judd–Ofelt (J–O) parameters and radiative parameters of the SLLB:Sm10 glass (1.0 mol% Sm3+ ion‐doped glass) were calculated using J–O theory. From the emission spectra, among all the synthesized glass, SLLB:Sm10 glass had the highest emission intensity for 4G5/26H11/2 transition (610 nm). Emission parameters, such as stimulated emission cross‐section and optical gain bandwidth, were calculated. For all concentrations of Sm3+ ions, the decay profile showed an exponential nature and decreased when the Sm3+ ion concentration was increased due to a concentration quenching effect. This result suggests that the synthesized SLLB:Sm10 glass could be used for application in high‐density optical memory devices.  相似文献   
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Molecular and Cellular Biochemistry - Latest strategies for cancer treatment primarily focus on the use of chemosensitizers to enhance therapeutic outcome. N-3 PUFAs have emerged as the strongest...  相似文献   
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兴都库什喜马拉雅地区高海拔树木生长对气候变化的响应 高海拔地区快速升温可能导致树木对温度响应更为敏感,而限制高海拔地区树木生长的关键气候因子以及气候变化对树木生长产生多大程度的影响尚不清楚。本研究在兴都库什喜马拉雅地区收集了73 个样点的树轮数据,包括3个优势属的树种(Abies属、Juniperus属和Picea属),样点海拔均在3000 m以上。 将时间动态规整(dynamic time warping)的方法用于建立亚区域年表,以考虑不同站点年表之间变化的同步 性。同时,定量分析了气候因子对树木生长的贡献以及树木生长与气候因子关系的时空动态。研究结果发现,73个站点年表可以聚为3类,且与其所处的生物气候区相对应,即西喜马拉雅地区,中东喜马拉雅地区和藏东南地区。在干旱的西喜马拉雅地区,树木生长与冬、春两季的降水呈正相关关系,而在湿润的藏东南地区,树木生长与冬季温度和春季降水呈正相关关系。树木生长受最低温度的影响最大,特别是冬季温度,其重要性从西到东呈现递增趋势。滑动窗口相关分析表明,在中西喜马拉雅地区,影响树木生长的冬季温度信号在减弱,然而在藏东南地区该信号随着1980年以来的快速升温而增强。本研究结果表明,若该地区升温持续,在西喜马拉雅地区可能会因变暖引起的水分亏缺而造成森林衰退,而在藏东南地区因树木生长得益于变暖而使得森林扩张。  相似文献   
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Probiotics and Antimicrobial Proteins - The outbreak of diseases leading to substantial loss is a major bottleneck in aquaculture. Over the last decades, the concept of using feed probiotics was...  相似文献   
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Pathogenic and spoilage fungi cause enormous challenges to food related fatal infections. Plant essential oil based classical emulsions can functions as antifungal agents. To investigate the antifungal spectrum, that is the scope of the nanoemulsion composed of Cleome viscosa essential oil and Triton-x-100 fabricated by ultrasonication method. Minimum inhibitory and fungicidal concentration of essential oil nanoemulsion (EONE) was tested against food borne pathogenic C. albicans. The MIC and MFC values ranged from 16.5 to 33 µl/ml with significant reduction on biofilm of C. albicans isolates. The alteration of molecular fingerprints was confirmed by Fourier transformed infrared spectroscopy and subsequent reduction of chitin levels in cell walls was noted by spectroscopic analysis. The EONE and their bioactive compounds cause collateral damage on C. albicans cells.  相似文献   
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