Genetics of allopatric populations of the montane vole ( Microtus montanus ) and Mogollon vole ( Microtus mogollonensis ) in the American Southwest

Variation at 21 allozyme loci and 10 restriction enzymes within the mitochondrial DNA control region was assessed among 3 allopatric populations of montane vole ( Microtus montanus ) in the American Southwest. Among populations of M. montanus , the population from the White Mountains, Arizona, was most genetically divergent. Genetic and biogeographic evidence supported recognition of the White Mountains population as a distinct subspecies, M. m. arizonensis . Results also supported recognition of the Mogollon vole ( Microtus mogollonensis ) as distinct from the Mexican vole ( Microtus mexicanus ).     

Mab HIM70对人Np NADPH氧化酶的调节（Ⅱ）

在发现Mab HIM70对Np NADPH氧化酶胸浆组分p47^phox、p67^phox和Rac2的表达和参与NADPH氧化酶活化均有降调节作用基础上,进一步探索了Mab HIM70对该降调节作用的机理。发现Mab HIM70可能对NADPH氧化酶上游PKC、PTK及PI3K信号传递途径的活化水平有降调节作用,该单抗对NADPH氧化酶活化有降调节的作用可能与此有关。     

交通流量变化对碳通量特征的影响

基于涡度相关技术提供的碳通量数据、定点连续观测的交通流量数据及数理统计分析的方法,探讨了2012年和2018年碳通量和交通流量的变化及其主要影响因素,分析了交通流量对碳通量变化的影响。主要结果如下：1）2018年日平均交通流量明显高于2012年的,由日均5 300辆增加到日均11 600辆;2）2012年与2018年的二氧化碳（CO₂）通量日变化均呈现双峰型曲线,交通流量的高峰时段与CO₂通量值的峰值相对应,分别为3.86 μmol·m^-2·s^-1和4.96 μmol·m^-2·s^-1;3）基于碳通量与交通流量的线性回归分析表明,2012年CO₂通量变化与交通流量变化具有显著的正相关性,交通流量对该区域碳通量贡献了18%,但2018年CO₂通量与交通流量无显著关系。     

Stereospezifität der Wirkung von Emetin

Summary (-)-Emetine, as prepared by total synthesis, has the same antiamebic activity and toxicity as the natural alkaloid. On the contrary its antipode and rac. isoemetine are not active and practically non-toxic. A relationship between configuration and antiamebic activity has thus been demonstrated for various representatives of the emetine series.     

Structural characterization of the molecular platform for type III secretion system assembly

Type III secretion systems (TTSSs) are multi-protein macromolecular 'machines' that have a central function in the virulence of many Gram-negative pathogens by directly mediating the secretion and translocation of bacterial proteins (termed effectors) into the cytoplasm of eukaryotic cells. Most of the 20 unique structural components constituting this secretion apparatus are highly conserved among animal and plant pathogens and are also evolutionarily related to proteins in the flagellar-specific export system. Recent electron microscopy experiments have revealed the gross 'needle-shaped' morphology of the TTSS, yet a detailed understanding of the structural characteristics and organization of these protein components within the bacterial membranes is lacking. Here we report the 1.8-A crystal structure of EscJ from enteropathogenic Escherichia coli (EPEC), a member of the YscJ/PrgK family whose oligomerization represents one of the earliest events in TTSS assembly. Crystal packing analysis and molecular modelling indicate that EscJ could form a large 24-subunit 'ring' superstructure with extensive grooves, ridges and electrostatic features. Electron microscopy, labelling and mass spectrometry studies on the orthologous Salmonella typhimurium PrgK within the context of the assembled TTSS support the stoichiometry, membrane association and surface accessibility of the modelled ring. We propose that the YscJ/PrgK protein family functions as an essential molecular platform for TTSS assembly.     

Continuous magnetic reconnection at Earth's magnetopause

The most important process that allows solar-wind plasma to cross the magnetopause and enter Earth's magnetosphere is the merging between solar-wind and terrestrial magnetic fields of opposite sense-magnetic reconnection. It is at present not known whether reconnection can happen in a continuous fashion or whether it is always intermittent. Solar flares and magnetospheric substorms--two phenomena believed to be initiated by reconnection--are highly burst-like occurrences, raising the possibility that the reconnection process is intrinsically intermittent, storing and releasing magnetic energy in an explosive and uncontrolled manner. Here we show that reconnection at Earth's high-latitude magnetopause is driven directly by the solar wind, and can be continuous and even quasi-steady over an extended period of time. The dayside proton auroral spot in the ionosphere--the remote signature of high-latitude magnetopause reconnection--is present continuously for many hours. We infer that reconnection is not intrinsically intermittent; its steadiness depends on the way that the process is driven.     

利用网络环境培养特色信息技术人才的教学模式探讨

阐述了网络技术与信息处理专业课程的特点及其教学模式改革的必要性．通过对课程结构的调整、教学手段的创新以及教学资源的优化控制等手段，探讨了更符合信息技术专业特点的人才培养方式。     

New distributional records of the red squirrel ( Tamiasciurus hudsonicus ) in western New Mexico and evidence for its extirpation from the Zuni Mountains

In the American Southwest, the red squirrel ( Tamiasciurus hudsonicus ) occurs as disjunct populations in coniferous forests on mountaintops. There is a paucity of information concerning the species’ distribution and habitat in western New Mexico. I report new records that document and verify the occurrence of red squirrels in additional montane areas in west central New Mexico, including the Mangas Mountains, Canovas Rim, Turner Mountain, Tularosa Mountains, Elk Mountains, Bearwallow Mountain, and Pinos Altos Mountains. I also report observations of red squirrels from an atypical habitat—low-elevation riparian forests. These new records suggest that the geographic distribution of the species in west central New Mexico is broader than indicated by existing records. However, I also document the apparent extirpation of red squirrels from the Zuni Mountains in northwestern New Mexico. The red squirrel is one of several avian and mammalian species associated with mixed coniferous forests that have become extirpated in this mountain range.