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Effects of the Size of Cosmological N-body Simulations on Physical Quantities– II：Halo Formation and Destruction Rate
Large scale structure of Universe N-body simulations galaxies
2009/5/12
In this study we show how errors due to finite box size
affect formation and the destruction rate for haloes in cosmological N-body
simulations. In an earlier study we gave an analytic prescription ...
THE FUTURE OF GALAXIES AND THE FATE OF INTELLIGENT LIFE
GALAXIES gaseous content INTELLIGENT LIFE
2009/3/19
We investigate the influence of recent advances in research on the
gaseous content of the universe on our knowledge of star formation histories of spiral
galaxies. The discovery of low-redshift popu...
The Fate of Dwarf Galaxies in Clusters and the Origin of Intracluster Stars
Cosmology—galaxies clusters dwarfs interactions—methods numerical
2010/9/15
The main goal of this paper is to compare the relative importance of destruction by tides vs. destruction by mergers, in order to assess if tidal destruction of galaxies in clusters is a viable scenar...
BROWN DWARF ACCRETION：NONCONVENTIONAL STAR FORMATION OVER VERY LONG TIMESCALES
Stars low-mass,brown dwarfs-Galaxy evolution-ISM general
2009/2/23
We investigate the process of accretion of interstellar gas by the
Galactic population of brown dwarfs over very long timescales typical for physical
eschatology. In particular, we use the classical...
WHY THERE ARE NO ELLIPTICAL GALAXIES MORE FLATTENED THAN E7. THIRTY YEARS LATER
dark matter-Galaxies evolution-Galaxies formation-Galaxies halos-Galaxies structure
2009/2/18
WHY THERE ARE NO ELLIPTICAL GALAXIES MORE FLATTENED THAN E7. THIRTY YEARS LATER。
THE ANALYSIS OF THE POSSIBLE THERMAL EMISSION AT RADIO FREQUENCIES FROM AN EVOLVED SUPERNOVA REMNANT HB 3 (G132.7+1.3)：REVISITED
Radiation mechanisms thermal-Radio continuum general-ISM supernova remnants-ISM individual objects HB3
2009/1/19
It has recently been reported that some of the °ux density values
for an evolved supernova remnant (SNR) HB 3 (G132.7+1.3) are not accurate
enough. In this work we therefore revised the analysis of ...
《自然》杂志9月18日内容精选
2007/8/28
封面故事：太阳发光度的变化太阳能量输出(或发光度)的微小变化因其对气候变化的意义而引起人们的注意和争论。这种变化源自11年的太阳黑子周期中日冕的暗结构(黑子)和亮结构(光斑)。1978年以来，科学家可以用卫星对这些结构进行准确追踪，并且发现它们的变化为0.07%。Foukal等人对我们在了解太阳发光度变化及其对地球上能量平衡的影响方面所取得的最新进展进行了评述，他们得出结论认为，自17世纪以来的太...
8月17日英国《自然》杂志内容精选
英国
2007/8/28
影响核小体定位的因素真核基因组在活体中不以裸露DNA形式存在，但在被称为染色质的蛋白—DNA复合物中是以裸露DNA形式存在的。染色质含有核小体，它们是紧紧包裹在一个组蛋白核心周围的短DNA片段，排斥大多数结合DNA的蛋白，所以起抑制剂的作用。在一项研究工作中，研究人员将计算方法和实验方法结合起来，用以确定核小体对DNA序列的偏好，并预测整个基因组范围内核小体的组织。酵母基因组编码一个内在的核小体组...
10月19日《自然》杂志内容精选
2007/8/21
美中期选举在科学问题上做文章11月的中期选举关系重大：民主党在众议院中只需要15个席位、在参议院中只需要6个席位就能成为多数党。对布什总统来说，这可能意味着一个重振雄风的总统任期或一个无所作为的“跛鸭”期之间的区别。在一个差距很小的选举中，两党都在偶然地、非典型地转向科学来试图影响选民。总统最近通过行使否决权来否决胚胎干细胞研究的做法，为共和党和民主党试图证明各自的候选人与众不同的努力都提供了新的...