SAR ADC驱动运算放大器的选择

运算放大器输出级极限 运算放大器的轨至轨运行是指其输入级或输出级,或者是指其输入级与输出级.作为驱动SAR ADC输入端的一个缓冲器,我们更关注运算放大器轨至轨的输出能力.     

Metabolomic Evidence for Peroxisomal Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic and debilitating disease characterized by unexplained physical fatigue, cognitive and sensory dysfunction, sleeping disturbances, orthostatic intolerance, and gastrointestinal problems. People with ME/CFS often report a prodrome consistent with infections. Using regression, Bayesian and enrichment analyses, we conducted targeted and untargeted metabolomic analysis of plasma from 106 ME/CFS cases and 91 frequency-matched healthy controls. Subjects in the ME/CFS group had significantly decreased levels of plasmalogens and phospholipid ethers (p < 0.001), phosphatidylcholines (p < 0.001) and sphingomyelins (p < 0.001), and elevated levels of dicarboxylic acids (p = 0.013). Using machine learning algorithms, we were able to differentiate ME/CFS or subgroups of ME/CFS from controls with area under the receiver operating characteristic curve (AUC) values up to 0.873. Our findings provide the first metabolomic evidence of peroxisomal dysfunction, and are consistent with dysregulation of lipid remodeling and the tricarboxylic acid cycle. These findings, if validated in other cohorts, could provide new insights into the pathogenesis of ME/CFS and highlight the potential use of the plasma metabolome as a source of biomarkers for the disease.     

Phytotoxic properties of cnicin,a sesquiterpene lactone fromcentaurea maculosa (spotted knapweed)

Water and solvent extracts from the aerial tissues ofCentaurea maculosa, spotted knapweed, inhibited the root growth of lettuce. Column chromatography and lettuce bioassay of a chloroform extract led to the isolation of cnicin, a sesquiterpene lactone. Pure cnicin was bioassayed at 0, 1, 2, 4, 6, 8, and 10 mg/5 ml water with lettuce, created wheatgrass, bluebunch wheatgrass, rough fescue, western larch, lodgepole pine, and spotted knapweed. Germination was inhibited at one or more concentrations for all species except lodgepole pine and spotted knapweed. Growth, particularly of the roots, was retarded between 1 and 4 mg of cnicin. Lettuce, bluebunch wheatgrass, and spotted knapweed were inhibited significantly at all concentrations tested.     

We need research on what constitutes good journal papers—and good editing—not guesswork on how to improve manuscriptsp.

Comments that M. Boor's (1986) suggestions to improve articles published in professional journals are unsubstantiated guesses and urges Boor to research his ideas. An example illustrates how Boor's guesses are contradicted by actual data. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Two-dimensional grain growth in rapidly solidified succinonitrile films

The kinetics and topological mechanisms of normal grain growth have been examined throughin situ dynamic studies on rapidly solidified succinonitrile (SCN). Thein situ studies allowed for continuous monitoring of the evolution of individual grains during growth. We have assessed the Mullins—Von Neumann topological grain growth law and the Burke—Turnbull parabolic rate law and have determined rate constants that describe grain growth. This work demonstrates that both laws are both obeyed globally and consistently. Thesein situ studies permit one to follow the unit operations associated with grain growth kinetics. This article demonstrates the usefulness of succinonitrile as a model analog system for studying grain growth. This article is based on a presentation made in the symposium “Fine Grains And Their Growth in Rapidly Solidified Materials,” TMS Materials Week ’93, Pittsburgh, PA, October 18–21, 1993.     

敏捷夹具CAD系统组成与自动构形设计方法研究

介绍了敏捷夹具系统组成,阐述了敏捷夹具的层次表示结构,提出了计算机辅助敏捷夹具自动构形可行的研究方法。     

敏捷企业（下）

上半部分全面介绍了敏捷企业的有关概念和企业开展敏捷化工程的有关问题。从企业外部到企业内部，对影响企业敏捷性的因素做了比较详细的分析。给出了一个供美国工业界实施敏捷化工物关键因素优优表，并对中国企业如何利用目前的机遇，通过建立全国一致的商务交换标准和技术体系来国际大合作的问题提出了具体的建议。下半部分从国工程的概念出发，着重描述了ＲＲＳ的概念，并通过实例进一步阐述了ＲＲＳ的１０条设计准则。