钢琴伴奏艺术在声乐表现艺术中的魅力

钢琴作为乐器之王,其可以为人声,或是对任何一种乐器进行伴奏,尤其钢琴伴奏在声乐表现中承担了渲染及补充音乐情绪的重要作用。本文首先简述了钢琴伴奏在声乐表演艺术中的地位,进而对钢琴伴奏在声乐表演艺术中的作用进行了探讨,最后总结了在钢琴伴奏与声乐的完美配合上需要注意的几个方面。     

Rapid phenotypic evolution with shallow genomic differentiation during early stages of high elevation adaptation in Eurasian Tree Sparrows

Known as the ‘third polar region’, the Qinghai-Tibet Plateau represents one of the harshest highland environments in the world and yet a number of organisms thrive there. Previous studies of birds, animals and humans have focused on well-differentiated populations in later stages of phenotypic divergence. The adaptive processes during the initial phase of highland adaptation remain poorly understood. We studied a human commensal, the Eurasian Tree Sparrow, which has followed human agriculture to the Qinghai-Tibet Plateau. Despite strong phenotypic differentiation at multiple levels, in particular in muscle-related phenotypes, highland and lowland populations show shallow genomic divergence and the colonization event occurred within the past few thousand years. In a one-month acclimation experiment investigating phenotypic plasticity, we exposed adult lowland tree sparrows to a hypoxic environment and did not observe muscle changes. Through population genetic analyses, we identified a signature of polygenic adaptation, whereby shifts in allele frequencies are spread across multiple loci, many of which are associated with muscle-related processes. Our results reveal a case of positive selection in which polygenic adaptation appears to drive rapid phenotypic evolution, shedding light on early stages of adaptive evolution to a novel environment.     

Large-scale multiferroic complex oxide epitaxy with magnetically switched polarization enabled by solution processing

Complex oxides with tunable structures have many fascinating properties, though high-quality complex oxide epitaxy with precisely controlled composition is still out of reach. Here we have successfully developed solution-based single-crystalline epitaxy for multiferroic (1-x)BiTi_(1-y)/2Fe_yMg_(1-y)/2O₃–(x)CaTiO₃ (BTFM–CTO) solid solution in large area, confirming its ferroelectricity at the atomic scale with strong spontaneous polarization. Careful compositional tuning leads to a bulk magnetization of 0.07 ± 0.035 μ_B/Fe at room temperature, enabling magnetically induced polarization switching exhibiting a large magnetoelectric coefficient of 2.7–3.0 × 10⁻⁷ s/m. This work demonstrates the great potential of solution processing in large-scale complex oxide epitaxy and establishes novel room-temperature magnetoelectric coupling in epitaxial BTFM–CTO film, making it possible to explore a much wider space of composition, phase, and structure that can be easily scaled up for industrial applications.     

Understanding human influence on climate change in China

China''s climate has been warming since the 1950s, with surface air temperature increasing at a rate higher than the global average. Changes in climate have exerted substantial impacts on water resources, agriculture, ecosystems and human health. Attributing past changes to causes provides a scientific foundation for national and international climate policies. Here, we review recent progress in attributing the observed climate changes over past decades in China. Anthropogenic forcings, dominated by greenhouse gas emissions, are the main drivers for observed increases in mean and extreme temperatures. Evidence of the effect of anthropogenic forcings on precipitation is emerging. Human influence has increased the probability of extreme heat events, and has likely changed the occurrence probabilities for some heavy precipitation events. The way a specific attribution question is posed and the conditions under which the question is addressed present persistent challenges for appropriately communicating attribution results to non-specialists.     

产业集群竞争力的形成机制分析

基于产业集群的特性和相关理论,分别从内源形成机制和外源形成机制的角度,剖析了产业集群竞争力形成和强化的驱动因素,旨在为提升产业集群竞争力提供理论指导.     

Genomic diversity and post-admixture adaptation in the Uyghurs

Population admixture results in genome-wide combinations of genetic variants derived from different ancestral populations of distinct ancestry, thus providing a unique opportunity for understanding the genetic determinants of phenotypic variation in humans. Here, we used whole-genome sequencing of 92 individuals with high coverage (30–60×) to systematically investigate genomic diversity in the Uyghurs living in Xinjiang, China (XJU), an admixed population of both European-like and East-Asian-like ancestry. The XJU population shows greater genetic diversity, especially a higher proportion of rare variants, compared with their ancestral source populations, corresponding to greater phenotypic diversity of XJU. Admixture-induced functional variants in EDAR were associated with the diversity of facial morphology in XJU. Interestingly, the interaction of functional variants between SLC24A5 and OCA2 likely influences the diversity of skin pigmentation. Notably, selection has seemingly been relaxed or canceled in several genes with significantly biased ancestry, such as HERC2–OCA2. Moreover, signatures of post-admixture adaptation in XJU were identified, including genes related to metabolism (e.g. CYP2D6), digestion (e.g. COL11A1), olfactory perception (e.g. ANO2) and immunity (e.g. HLA). Our results demonstrated population admixture as a driving force, locally or globally, in shaping human genetic and phenotypic diversity as well as in adaptive evolution.     

教育均衡发展:理论、指标及测算方法

教育均衡实质上是指在教育公平思想和教育平等原则的支配下,教育机构和受教育者在教育活动中有平等待遇的理想和确保其实际操作的教育政策和法律制度。教育均衡发展的本质是追求教育平等,实现教育公平。教育均衡发展从宏观层面分析是教育供给与需求的均衡,从中观层面分析是教育资源配置的均衡,从微观层面分析是学校教育过程包括内部课程教学资源配置的均衡、教育结果的均衡以及教育评价的均衡。教育均衡发展是一个历史范畴,按其实现程度可分为四个阶段。建立适应我国国情的基础教育特别是义务教育均衡发展指数,科学地选择基础教育均衡发展的要素,明确基础教育均衡发展的目标,具有重要的现实意义。数据分析表明,我国基础教育从整体上看正在趋向均衡。     

对中学化学教育科研的思考

分析了中学化学教师科研工作现状,从微观层面阐述了中学化学教育科研的意义,提出了中学化学教育科研的内容、研究方法以及研究策略.     

嵌入式实时数据库系统并发控制协议A-Based OCC-WAIT50

本文主要是把替代引入到乐观并发控制协议OCC-WAIT50中来,提出了一种实时并发控制协议A-BasedOCC-WAIT50。由于各替代的资源需求不同,所以,参与资源竞争受阻的机会也不同。对于处于接纳队列中的事务,选择一个最优替代参与并发控制,可以避免或减少冲突的发生。而当冲突不可避免时,再采用乐观并发控制协议OCC-WAIT50进行冲突消解。     

南京新旧探空系统资料差异分析

通过对新旧探空系统(即L波段探空系统和59-701探空系统)中GST1型数字式电子探空仪和59型机械式探空仪所探测到的探空资料,采用标准差和平均差的方法比较分析了南京站同步高空观测的一个月资料,分别从探空温度、探空高度、探空湿度等方面作了详细地差异分析,对比了两种高空探测系统所获得资料的差异及其所产生差异的原因分析.结果表明:L波段探空系统比59-701探空系统所测得的高空探测温度和探测高度资料更加稳定、离散率更小;所测得的湿度,59-701探测系统有较高的稳定性,而L波段探测系统则有更高的灵敏度,两套探测系统的湿度都是随探空高度的增大而差值变大.通过对新旧探空系统地分析,以便更好地利用和改进现有的高空探测系统.