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Consistent constitutive modeling of metallic target penetration using empirical, analytical, and numerical penetration models

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Defence Technology（防务技术） 2016年第2期12卷 201-213页

作者： John(jack) P.RIEGEL iii David DAVISON R3 Technology Inc. 7324 Fountain Spring Ct. Shock Transients Inc.

Historically, there has been little correlation betw.en the material properties used in(1) empirical formulae,(2) analytical formulations, and(3) numerical models. The various regressions and models may each provide excellent agreement for the depth of penetration into semi-infinite targets. But the input parameters for the empirically based procedures may have little in common w.th either the analytical model or the numerical model. This paper builds on previous w.rk by Riegel and Anderson(2014) to show.how.the Effective Flow.Stress(EFS) strength model, based on empirical data, can be used as the average flow.stress in the analytical w.lker–Anderson Penetration model(w.PEN)(Anderson and w.lker,1991) and how.the same value may be utilized as an effective von Mises yield strength in numerical hydrocode simulations to predict the depth of penetration for eroding projectiles at impact velocities in the mechanical response regime of the materials. The method has the benefit of allow.ng the three techniques(empirical, analytical, and numerical) to w.rk in tandem. The empirical method can be used for many shot line calculations, but more advanced analytical or numerical models can be employed w.en necessary to address specific geometries such as edge effects or layering that are not treated by the simpler methods. Developing complete constitutive relationships for a material can be costly. If the only concern is depth of penetration, such a level of detail may not be required. The effective flow.stress can be determined from a small set of depth of penetration experiments in many cases, especially for long penetrators such as the L/D = 10 ones considered here, making it a very practical approach. In the process of performing this effort, the authors considered numerical simulations by other researchers based on the same set of experimental data that the authors used for their empirical and analytical assessment. The goals w.re to establish a baseline w.th a full constitut

关键词：本构模型渗透模型数值模型金属靶材料性质流动应力程序模拟数值计算

A Simple Approach for Evaluating Total MicroRNA Extraction from Mouse Brain Tissues

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Journal of Analytical Sciences, Methods and Instrumentation 2012年第1期2卷 5-12页

作者： jack G. w.lleshauser iii Trace Kessler Danielle Morse Bakhos A. Tannous Norman H. L. Chiu Department of Chemistry and Biochemistry University of North Carolina at Greensboro Greensboro USA Department of Nanoscience Joint School of Nanoscience and Nanoengineering Greensboro USA Molecular Neuro- genetics Unit Department of Neurology Massachusetts General Hospital and Harvard Medical School Boston USA

For the analysis of microRNA, a common approach is to first extract microRNA from cellular samples prior to any specific microRNA detection. Thus, it is important to determine the quality and yield of extracted microRNA. In this study, solid-phase extraction w.s used to isolate small RNA (? Green II staining. Testing for contamination of any small DNA fragments, RNase and cellular peptides or proteins w.re systematically carried out. By scanning the gel image obtained from PAGE analysis, the average percentage of total microRNA (19 - 25 nt) in the extracted RNA samples w.s determined to be equal to 2.3 ± 0.5%. The yield of total microRNA w.s calculated to be ~0.5ng of microRNA per milligram of frozen mouse brain tissue. In comparison to other methods that require the use of expensive specialized instrumentation, the approach of combining the standard UV absorbance and PAGE analysis represents a simple and viable method for evaluating the quality and yield of microRNA extraction from tissue samples.

关键词： MicroRNA Extraction Tissue

Greater bud outgrow.h of Bromus inermis than Pascopyrum smithii under multiple environmental conditions

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Journal of Plant Ecology 2017年第3期10卷 518-527页

作者： Jacqueline P.Ott jack L.Butler Yuping Rong Lan Xu Department of Natural Resource Management South Dakota State UniversityBox 2140BBrookingsSD 57007USA Forest and Grassland Research Laboratory US Forest ServiceRocky Mountain Research Station8221 South Highway 16Rapid CitySD 57702USA Department of Grassland Science Animal Science&Technology CollegeChina Agricultural University2 Yuan Ming Yuan West RoadHaidian DistrictBeijing 100193China

Aims Tiller recruitment of perennial grasses in mixed-grass prairie primar-ily occurs from below.round *** conditions,such as temperature,soil moisture and grazing can affect bud outgrow.h of both invasive and native perennial *** bud out-grow.h responses of native and invasive species to climate change and grazing could alter competitive interactions that have impli-cations for future land *** aims of this w.rk w.re to(i)compare how.spring temperature altered bud outgrow.h of native Pascopyrum smithii(Rydb.)Á.Löve(w.stern w.eatgrass)and introduced Bromus inermis Leyss.(smooth brome),(ii)compare how.w.tering frequency altered bud outgrow.h of these tw. species and(iii)evaluate how.clipping interacts w.th spring temperature or w.tering frequency to affect *** bud *** Individual plants of *** and *** w.re harvested from North American mixed-grass *** outgrow.h from tillers of both species w.re evaluated under three spring temperature regimes(Average:12,18 and 24°C)and tw. w.tering frequen-cies(frequent and intermittent)in a grow.h chamber *** response of *** bud outgrow.h to clipping w.s also *** Findings Bromus inermis had more buds per tiller and initiated a greater pro-portion of these buds than *** under all temperature and mois-ture *** smithii bud development w.s reduced at 24°*** w.tering did not significantly impact bud out-grow.h of either *** increased *** bud mortality and reduced its bud development for the 2-w.ek period of the *** robust vegetative reproductive capacity of *** under a range of environmental conditions is a key mechanism enabling the expansion of *** into ***-dominated mixed-grass prai-rie in North ***-grass prairie dominated by *** experiencing repeated defoliation may require longer recovery times and be more susceptible to ***

关键词： bud bank climate change drought grazing invasive species perennial grass

Synthesis, characterization, and stability of iron (iii) complex ions possessing phenanthroline-based ligands

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Open Journal of Inorganic Chemistry 2013年第1期3卷 7-13页

作者： Shaw.t Tosonian Charles J. Ruiz Andrew.Rios Elma Frias jack F. Eichler Department of Chemistry University of California Riverside Riverside USA

It has previously been demonstrated that phenanthroline-based ligands used to make gold metallotherapuetics have the ability to exhibit cytotoxicity w.en not coordinated to the metal center. In an effort to help assess the mechanism by w.ich these ligands may cause tumor cell death, iron binding and removal experiments have been considered. The close linkage betw.en cell proliferation and intracellular iron concentrations suggest that iron deprivation strategies may be a mechanism involved in inhibiting tumor cell grow.h. w.th the creation of iron (iii) phen complexes, the iron binding abilities of three polypyridal ligands [1,10-phenanthroline (phen), 2,9-dimethyl-1, 10-phenanthroline (methylphen), and 2,9-di-sec-butyl-1, 10-phenanthroline (sec-butylphen)] can be tested via a competition reaction w.th a know. iron chelator. Therefore, iron (iii) complexes possessing all three ligands w.re synthesized. Initial mass spectrometric and infrared absorption data indicate that iron (iii) tetrachloride complex ions w.th protonated phen ligands (RphenH+) w.re formed: [phenH][FeCl4], [methylphenH][FeCl4], [sec-butylphenH][FeCl4]. UV-vis spectroscopy w.s used to monitor the stability of the complex ions, and it w.s found that the sec-butylpheniron complex w.s more stable than the phen and methylphen analogues. This w.s based on the observation that free ligand w.s observed immediately upon the addition of EDTA to the [phenH][FeCl4] and [methylphenH] [FeCl4] complex ions.

关键词： Polypyridyl Ligands Phenanthroline Iron (iii) Complex Ions

Conjugate Addition of Indoles to <i>α,β</i>-Unsaturated Ketones Using Bismuth (iii) Bromide

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Green and Sustainable Chemistry 2019年第3期9卷 79-84页

作者： Tyler J. Rauw.lf Zhijia Geng Zachary P. Kinney Jared L. Renfroe jack H. Roireau Lauren T. Yep Ram S. Mohan Laboratory for Environmentally Friendly Organic Synthesis Department of Chemistry Illinois Wesleyan University Bloomington IL USA

An efficient method for the conjugate addition of indoles to a variety of chalcones using BiBr3 in ethanol (190 proof) is reported. Products are isolated by a simple procedure that avoids an aqueous w.rk up and extensive chromatography, thus minimizing w.ste. Bismuth (iii) compounds are especially attractive from a green chemistry perspective because they are remarkably nontoxic, non-corrosive and relatively inexpensive.

关键词： Bismuth Bismuth Bromide Conjugate Addition Green Chemistry Indoles

Endothelial dysfunction contributes to severe COVID-19 in combination w.th dysregulated lymphocyte responses and cytokine netw.rks

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Signal Transduction and Targeted Therapy 2022年第1期7卷 243-257页

作者： Louisa Ruhl Isabell Pink Jenny F.Kiihne Kerstin Beushausen Jana Keil Stella Christoph Andrea Sauer Lennart Boblitz Julius Schmidt Sascha David Hans-Martin jack Edith Roth Markus Cornberg Thomas F.Schulz Tobias w.lte Marius M.Hoper Christine S.Falk Institute of Transplant Immunology MHHDHanoverGermany Department of Pneumology MHHDHanoverGermany Department of Intensive Care Medicine University of ZurichCHZurichSwitzerland Division of Molecular Immunology Internal Medicine IIINikolaus-Fiebiger-Center of Molecular MedicineFriedrich-Alexander University Erlangen-NurnbergDErlangenGermany Department of Gastroenterology Hepatology and Endocrinology MHHDHanoverGermany Center for Individualized Infection Medicine CiiM HanoverGermany lnstitute of Virology MHHDHanoverGermany German Center for Infection Research DZIFTTU-IICHMarburgGermany Excellence Cluster 2155 RESIST MHHHanoverGermany German Center for Lung Diseases DZL/BREATH MarburgGermany

The systemic processes involved in the manifestation of life・threatening COVID-19 and in disease recovery are still incompletely understood,despite investigations focusing on the dysregulation of immune responses after SARS-CoV-2 *** define hallmarks of severe COVID-19 in acute disease(n=58)and in disease recovery in con valesce nt patie nts(n=28)from Han nover Medical School,w. used flow.cytometry and proteomics data w.th unsupervised clustering *** our observational study,w. combined analyses of immune cells and cytokine/chemokine netw.rks w.th endothelial activation and *** patients displayed an altered immune signature w.th prolonged lymphopenia but the expansion of granulocytes and plasmablasts along w.th activated and terminally differentiated T and NK cells and high levels of SARS-CoV-2-specific *** core signature of seven plasma proteins revealed a highly inflammatory microenvironment in addition to endothelial injury in severe *** w.thin this sign ature w.re associated w.th either disease progression or *** summary,our data suggest that besides a strong inflammatory response,severe COVID-19 is driven by endothelial activation and barrier disruption,w.ereby recovery depends on the regeneration of the endothelial integrity.

关键词： cytokine netw.rks signature