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Cryogenic nanosecond and picosecond high average and peak power(HAPP) pump lasers for ultrafast applications

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High Power Laser Science and Engineering 2016年第2期4卷 37-67页

作者： David C.brown Sten Tornegrd joseph kolis Snake Creek Lasers LLC Clemson University Department of Chemistry

Using cryogenic laser technology, it is now possible to design and demonstrate lasers that have concomitant high average and peak powers, with near-diffraction-limited beam quality. We refer to these new laser systems as HAPP lasers. In this paper, we review important laser crystal materials properties at cryogenic temperature, with an emphasis on Yb lasers, and discuss the important design considerations, including the laser-induced damage threshold, nonlinear effects and thermal effects. A comprehensive model is presented to describe diode pulsed pumping with arbitrary duration and repetition rate, and is used with the Frantz–Nodvik equation to describe, to first order, the performance of HAPP laser systems. A computer code with representative results is also described.

关键词： cryogenic lasers high-average-power lasers high-peak-power lasers ultrafast lasers Yb lasers

Angiosperm phylogeny inferred from sequences of four mitochondrial genes

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Journal of Systematics and Evolution 2010年第6期48卷 391-425页

作者： Tory A.HENDRY joseph W.brown Geordan T.HUDSON Department of Ecology and Evolutionary Biology University of Michigan

An angiosperm phylogeny was reconstructed in a maximum likelihood analysis of sequences of four mitochondrial genes,atp1,matR,nad5,and rps3,from 380 species that represent 376 genera and 296 families of seed *** is largely congruent with the phylogeny of angiosperms reconstructed from chloroplast genes atpB,matk,and rbcL,and nuclear 18S *** basalmost lineage consists of Amborella and Nymphaeales(including Hydatellaceae).Austrobaileyales follow this clade and are sister to the mesangiosperms,which include Chloranthaceae,Ceratophyllum,magnoliids,monocots,and *** the exception of Chloranthaceae being sister to Ceratophyllum,relationships among these five lineages are not well *** eudicots,Ranunculales,Sabiales,Proteales,Trochodendrales,Buxales,Gunnerales,Saxifragales,Vitales,Berberidopsidales,and Dilleniales form a basal grade of lines that diverged before the diversification of rosids and *** rosids,the COM(Celastrales-Oxalidales-Malpighiales) clade is sister to malvids(or rosid II),instead of to the nitrogen-fixing clade as found in all previous large-scale molecular analyses of *** and Caryophyllales are members of an expanded asterid *** study shows that the mitochondrial genes are informative markers for resolving relationships among genera,families,or higher rank taxa across *** low substitution rates and low homoplasy levels of the mitochondrial genes relative to the chloroplast genes,as found in this study,make them particularly useful for reconstructing ancient phylogenetic relationships.A mitochondrial gene-based angiosperm phylogeny provides an independent and essential reference for comparison with hypotheses of angiosperm phylogeny based on chloroplast genes,nuclear genes,and non-molecular data to reconstruct the underlying organismal phylogeny.

关键词： angiosperm homoplasy mitochondrial gene molecular evolutionary rate phylogeny rosids.

Supporting farmer-managed irrigation systems in the Shigar valley, karakorum： Role of the government and Aga khan Rural Support Programme

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Journal of Mountain Science 2017年第10期14卷 2064-2081页

作者： joseph k.W.HILL Department of Rural Management Xavier Institute of Social Sciences (XISS) Dr Gamil Bulcke Path Post Box 7 Ranchi- 834001 India

Farmer-managed irrigation systems(FMIS) in the high altitude valleys of the karakorum,Pakistan, continue to be managed effectively despite increased pressure on the social arrangements that sustain them. Colonial era records shows that over a century ago government agencies undertook irrigation support projects. In the past three decades,government agencies and the non-government agency Aga khan Rural Support Programme(AkRSP), which channels foreign funds into the region, have actively engaged in the provision of irrigation support. This article seeks to explore whether such projects support or undermine farmer-managed irrigation systems and the complex institutional arrangements that underpin them. Field research using ethnographic and participatory methods was conducted in spring 2013 in the upper Shigar valley, Skardu district, GilgitBaltistan. The findings show that irrigation development is a political activity that involves village-based actors, religious leaders, local politicians,and government and non-government *** agencies operate in a largely top-down,engineering mode, their larger projects limited to villages suffering water scarcity. The local government provides small funds for renovation work of FMIS,though allocation of funds is highly politicized. Nongovernment agencies, for a variety of reasons including donor-funding cycles, apply a one-size-fitsall ‘participatory' model in an attempt to socially engineer rules and institutions. In communities divided by factionalism the use of such external models that stress formation of committees are unlikely to yield positive results, and could instead contribute to undermining the very systems they seek to support. This research argues that irrigation interventions should take care to build upon the rich and complex social arrangements that have sustained FMIS through the centuries.

关键词： Farmer-managed irrigation systems Institutional arrangements Government Aga khan Rural Support Programme Shigar valley karakorum

EVOLUTION AND INTERACTION OF δ-WAVES IN THE ZERO-PRESSURE GAS DYNAMICS SYSTEM

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Acta Mathematica Scientia 2024年第5期44卷 1801-1836页

作者： Abhishek DAS k.T.joseph Centre for Data Science Institute of Technical Education and Research(ITER)Siksha‘O’Anusandhan(Deemed to be University)BhubaneswarOdisha751030India Centre for Applicable Mathematics Tata Institute of Fundamental ResearchSharada NagarBangalore560065KarnatakaIndia

Evolution and interaction of plane waves of the multidimensional zero-pressure gas dynamics system leads to the study of the corresponding one dimensional *** this paper,we study the initial value problem for one dimensional zero-pressure gas dynamics *** the first equation is the Burgers equation and the second one is the continuity *** consider the solution with initial data in the space of bounded Borel *** we prove a general existence result in the algebra of generalized functions of *** we study in detail special solutions withδ-measures as initial *** study interaction of waves originating from initial data concentrated on two point sources and interaction with classical shock/rarefaction *** gives an understanding of plane-wave interactions in the multidimensional *** use the vanishing viscosity method in our analysis as this gives the physical solution.

关键词： zero-pressure gas dynamics delta-waves interaction of waves

Polarization variability arising from clumps in the winds of Wolf-Rayet stars

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Chinese Journal of Astronomy and Astrophysics 2009年第5期9卷 558-576页

作者： Qing-kang Li joseph E Cassinelli John C. brown Richard Ignace Department of Astronomy Beijing Normal University Beijing 100875 China Department of Astronomy University of Wisconsin-Madison 53711 USA Department of Physics and Astronomy University of Glasgow Glasgow G12 8QQ Scotland UK Department of Physics and Astronomy Eastern Tennessee State University USA

Polarimetric and photometric variability of Wolf-Rayet （WR） stars as caused by clumps in the winds is revisited. In our model, which is improved from Li et al., radial expansion of the thickness is accounted for, but we retain dependence on the β velocity law and stellar occultation effects. We again search for parameters that can yield results consistent with observations in regards to the mean polarization p, the ratio R = σp/σphot of polarimetric to photometric variability and the volume filling factor fV. Clump generation and spatial distribution are randomized by the Monte Carlo method so as to produce clumps which are, in the mean, distributed uniformly in space and have time intervals that obey a Gaussian distribution. The generated clumps move radially outward with a velocity law determined by a β index, and the angular size of clumps is assumed to be fixed. By fitting the observed σp/σphot and the volume filling factor fv, clump velocity taw index β （- 2） and clump ejection rate .N （- 1） are inferred, and are found to be well constrained. In addition, the subpeak features of broad emission lines seem to support the clump ejection rate. Meanwhile, the fraction of total mass loss rate that is contained in clumps is obtained by fitting observed polarization. We conclude that this picture of the clumps＇ properties produces a valuable diagnostic of WR wind structure.

关键词： stars mass loss -- stars Wolf-Rayet -- stars winds, outflows

Regulation of inflammasomes by ubiquitination

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Cellular & Molecular Immunology 2016年第6期13卷 722-728页

作者： joseph S Bednash Rama k Mallampalli Division of Pulmonary Allergy and Critical Care Medicine Department of Medicine Acute Lung injury Center of Excellence University of Pittsburgh Pittsburgh PA 15213 USA Department of Cell Biology and Physiology and Bioengineering University of Pittsburgh Pittsburgh PA 15213 USA Medical Specialty Service Line Veterans Affairs Pittsburgh Healthcare System Pittsburgh PA 15240 USA

Inflammasomes are multi-protein complexes that regulate the innate immune response by facilitating the release of inflammatory cytokines in response to pathogen exposure or cellular damage. Pro-inflammatory inflammasome signaling is vital to host defense and helps initiate the process of tissue repair following an insult to the host, but can be injurious, when excessive or chronic. As such, inflammasome activity is tightly regulated. Here we discuss one critical mechanism of inflammasome regulation, ubiquitination, that functions as a universal modulator of protein stability and trafficking. Recent studies have provided important insights into the regulation of inflammasome activation by protein ubiquitination. We review the molecular regulation of inflammasome function, specifically, as it relates to ubiquitination, and discuss the implications for the development of theraoeutics to soecificallv target aberrant inflammasome signaling.

关键词： deubiquitinase E3 ligase inflammasome innate immunity ubiqutin

Lead-phase and red-stripe color morphs of red-backed salamanders Plethodon cinereus differ in hematological stress indices:A consequence of differential predation pressure?

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Current Zoology 2010年第2期56卷 238-243页

作者： Andrew k.DAVIS joseph R.MILANOVICH D.B. Warnell School of Forestry and Natural Resources The University of Georgia

Throughout the animal kingdom there are species that have two or more phenotypic forms or ‘morphs＇, and many of these are amphibians. In North America, the red-backed salamander Plethodon cinereus can have either a red dorsal stripe or no dorsal stripe （lead-phase form）, and evidence to date indicates the lead-phase form incurs a greater number of attacks from predators. In a recent collection of 51 P cinereus, blood smears of both color morphs （35 red-stripe, 16 lead-phase） were examined to obtain numbers of circulating leukocytes （via light microscopy）, which can be used to indirectly estimate levels of stress hormones in vertebrates via a ‘hematological stress index＇, which is the ratio between the number of two leukocyte types （neutrophils and lymphocytes）. Our results showed that lead-phase salamanders tended to have greater numbers of circulating neutrophils and lower numbers of circulating lymphocytes than red-stripe morphs, leading to higher average neutrophil-lymphocyte ratios in lead-phase individuals. Since the salamanders were held （refrigerated） for 7 days before sampling, we cannot be certain if this effect is a stress reaction to the captivity or the normal level for this morph. However comparison with two sets of related salamanders that were captured and sampled immediately indicates the red-stripe salamanders were either not stressed from the captivity at all, or their white blood cell distributions had returned to normal after 7 days of captivity. Taken together, our results indicate that lead-phase forms of P. cinereus have higher stress levels than the red-stripe forms, which may be a consequence of their higher exposure to, and/or attacks from, predators. They may also indicate that the lead-phase form is less-suited to captivity than the red-stripe form of this species.

关键词： Red-backed salamander Plethodon cinereus Color polyrnorphism Hematological stress index Corticosterone

SOME EXACT SOLUTIONS OF 3-DIMENSIONAL ZERO-PRESSURE GAS DYNAMICS SYSTEM

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Acta Mathematica Scientia 2011年第6期31卷 2107-2121页

作者： k.T. joseph Manas R. Sahoo School of Mathematics Tata Institute of Fundamental Research

The 3-dimensional zero-pressure gas dynamics system appears in the modeling for the large scale structure formation in the universe. The aim of this paper is to construct spherically symmetric solutions to the system. The radial component of the velocity and density satisfy a simpler one dimensional problem. First we construct explicit solutions of this one dimensional case with initial and boundary conditions. Then we get special radial solutions with different behaviours at the origin.

关键词： zero-pressure gas dynamics spherically symmetric solutions

Comparative study of mechanical, corrosion and erosion-corrosion properties of cast hyper-duplex and super-duplex stainless steels

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International Journal of Minerals,Metallurgy and Materials 2020年第7期27卷 954-961页

作者： P.Nithin Raj P.k.Navaneethkrishnan k.Sekar M.A.joseph Department of Mechanical Engineering National Institute of TechnologyCalicutIndia

Duplex stainless steels(DSSs)used in subsea structures and desalination industries require high corrosion and erosion resistance as well as excellent mechanical *** newly introduced cast duplex grade ASTM A8907 A has a unique composition and is expected to have a much better resistance to corrosion and erosion compared with the super-duplex grades 5 A and 6 *** work is a comparative study of the mechanical properties,corrosion,and erosion-corrosion resistance of super-duplex grades 5 A and 6 A and the hyper-duplex grade 7 *** three DSSs exhibited equiaxial austenite islands in the ferrite matrix and balanced phase *** hardness of the grade 7 A was nearly 15%higher than those of the super-duplex grades,which is attributed to the effect of the higher contents of W and Mn in 7 *** impact toughness of grade 7 A was found to be lower than those of the super-duplex grades due to the carbide precipitation resulting from the partial substitution of Mo with *** oxide layer strengthening effect of rare earth elements and the higher pitting resistance equivalent number(PREN)of grade7 A resulted in higher corrosion *** harder and more passive grade 7 A showed a 35%lower material loss during erosion-corrosion.

关键词： hyper-duplex stainless steels erosion−corrosion electrochemical corrosion marine environment super-duplex stainless steels