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Dielectric confinement on exciton binding energy and nonlinear optical properties in a strained Zn_(1-x_(in))Mg_(x(in))Se/Zn_(1-x(out))Mg_(x(out))Se quantum well

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j.urnal of Semiconductors 2012年第9期33卷 1-7页

作者： j.Abraham Hudson mark A.j.hn Peter Department of Physics NPR Arts&Science CollegeNathamDindigul-624401India Department of Physics Government Arts CollegeMelur-625106MaduraiIndia

The band offsets for a Zn1-xin Mgxin Se/Zn1-xout Mgxout Se quantum well heterostructure are determined using the model solid theory. The heavy hole exciton binding energies are investigated with various Mg alloy contents. The effect of mismatch between the dielectric constants between the well and the barrier is taken into account. The dependence of the excitonic transition energies on the geometrical confinement and the Mg alloy is discussed. Non-linear optical properties are determined using the compact density matrix approach. The linear, third order non-linear optical absorption coefficient values and the refractive index changes of the exciton are calculated for different concentrations of magnesium. The results show that the occurred blue shifts of the resonant peak due to the Mg incorporation give the information about the variation of two energy levels in the quantum well width.

关键词： interband emission energy exciton binding energy quantum well

Patient Characteristics, Safety, and Tolerability With Telaprevir Treatment for HCV in the Clinic:a Retrospective, Multicenter Study

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j.urnal of Clinical and Translational Hepatology 2014年第2期2卷 65-73页

作者： Steven L. Flamm Paul j. Pockros Leif Bengtsson mark Friedman Northwestern University Feinberg School of Medicine Chicago Illinois USA Scripps Clinic and Scripps Translational Science Institute La Jolla California USA Vertex Pharmaceuticals Incorporated Boston Massachusetts USA

Background and Aims: There is a paucity of information regarding similarities and differences between patients from the phase 3 studies of telaprevir and those receiving telaprevir in clinical practice. Methods: This retrospective chart review evaluated baseline characteristics and follow-up safety and tolerability data for patients with hepatitis C virus (HCV) infection treated with telaprevir and peginterferon alfa and ribavirin (PR) in clinical practice. Results: In total, 338 charts from patients at four academic and three community US treatment centers who received telaprevir and PR and had at least 12 weeks of follow-up data were included;62%were from academic centers and 38% were from community centers. Of the 338 patients, 269 completed 12 weeks of telaprevir and PR;32 discontinued due to adverse events. Mean age was 55 years;patients were predominantly white (79.3%) males (58.9%) with genotype 1a HCV infection (61.8%);35.5%were reported to have cirrhosis at baseline;and 55.3%previously received PR. Hypertension and depres-sion were the most common comorbidities. Patient charac-teristics outside the per-protocol minimum criteria used in the phase 3 studies of telaprevir were, e.g., hemoglobin, 9.2%;albumin, 5.3%;platelets, 11.5%;and neutrophil count, 5.6%. Adverse events occurred in 329/338 (97.3%) patients, with anemia, fatigue, nausea, and rash being the most common. Of 38 hospitalizations, 26 were deemed related to telaprevir and PR. Three patients died due to pneumonia, septic shock, and hepatorenal syndrome (n=1 each). Conclusions: These findings complement those reported from rigorous, randomized controlled studies with telaprevir-based treatment and provide a general assess-ment of similarities and/or differences between patients from the phase 3 studies of telaprevir and those treated with telaprevir in clinical practice.

关键词： Hepatitis C virus Combination drug therapy Protease inhibitors Liver diseases

Phase Invariant Proper Orthogonal Decomposition for the Study of a Compressed Vortex

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j.urnal of Thermal Science 2005年第2期14卷 108-113页

作者： j.lien MOREAU mark FOGLEMAN G.CHARNAY j.BOREE Institut de Mécanique des Fluides UMR CNRS/INPT-UPS 5502 Allée du Pr Soula 31400 Toulouse FranceCornell University IthacaNew York 14853U.S.A.Institut de Mécanique des Fluides UMR CNRS/INPT-UPS 5502 Allée du Pr Soula 31400 ToulouseFranceLEA ENSMA UMR 6609 CNRS Futuroscope France

We propose here an experimental investigation of a vortex submitted to a radial perturbation while being compressed. This experiment reproduces a model situation of the complex flows that take place in a real engine cylinder. An isolated tumbling flow is first submitted to an inj.ction of fluid and then compressed and measurements are realised by Particle Image Velocimetry (PIV). The Proper Orthogonal Decomposition is known to be an unbiased method to identify the coherent structures of turbulent flows. It is possible to make this decomposition for a given phase or to create a set of basis functions with the whole set of compression stroke velocity ***, the experimental set-up will be presented, then the second part provides the POD principle. Results of phased POD decomposition of the compression of the unperturbated vortex will be presented. Finally results from the time invariant POD will be discussed to study the influence of the j.t perturbation in the compression of a vortex.

关键词： turbulence POD PIV cycle to cycle fluctuations.

Alternative expressions for stand diameter in complex forests

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Forest Ecosystems 2023年第3期10卷 328-336页

作者： mark j.Ducey j.hn A.Kershaw j.. Department of Natural Resources and the Environment University of New HampshireDurhamNHUSA Faculty of Forestry and Environmental Management University of New BrunswickFrederictonNBCanada

Quadratic mean diameter is the most frequently reported descriptor of the diameter distribution of *** such,it is often used as an indicator of forest stand structure,developmental stage,and ecological and economic ***,quadratic mean diameter can be heavily influenced by the presence or absence of large numbers of small stems in lower canopy strata,and it is also sensitive to left-truncation of the diameter distribution,making its interpretation across inventories with different protocols ***,we examine three alternative expressions of stand diameter:the arithmetic and quadratic mean diameter of the thickest 100 trees per hectare,and the basal area-weighted mean *** data from the United States Forest Inventory and Analysis program for New York and New England,these alternative expressions showed closer correlation with multiple stand structural variables than did quadratic mean diameter,including merchantable cubic and board foot volume per hectare,aboveground live tree carbon per hectare,and total number of live and dead standing trees greater than 40 cm diameter at breast height per hectare(previously proposed as an index of old-growth structure).Arithmetic and quadratic mean diameter of the thickest 100 trees per hectare showed nearly identical performance,and the strongest correlations across the *** develop closed-form expressions for these variables when the diameter distribution is a Weibull,and illustrate their behavior relative to quadratic mean diameter for that *** the reasons for prevalence of quadratic mean diameter as an indicator remain valid,we suggest that these alternative measures should be more widely reported and analyzed to give a more informative depiction of stand structure and development in complex forests.

关键词： Forest structure Diameter at breast height Weibull distribution

Mass Spectrometric Analyses Reveal a Central Role for Ubiquitylation in Remodeling the Arabidopsis Proteome during Photomorphogenesis

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Molecular Plant 2017年第6期10卷 846-865页

作者： Victor Aguilar-Hernandez Do-Young Kim Robert j. Stankey mark Scalf Lloyd M. Smith Richard D. Vierstra Department of Biology Washington University in St. Louis Campus Box 1137 One Brookings Drive St. Louis MO 63130 USA Department of Genetics 425-G Henry Mall Department of Chemistry 1101 University Avenue University of Wisconsin-Madison Madison WI 53706 USA Advanced Bio Convergence Center Pohang Technopark Gyeong-Buk South Korea 37668

The switch from skotomorphogenesis to photomorphogenesis is a key developmental transition in the life of seed plants. While much of the underpinning proteome remodeling is driven by light-induced changes in gene expression, the proteolytic removal of specific proteins by the ubiquitin-26S proteasome system is also likely paramount. Through mass spectrometric analysis of ubiquitylated proteins affinity-purified from etiolated Arabidopsis seedlings before and after red-light irradiation, we identified a number of influential proteins whose ubiquitylation status is modified during this switch. We observed a substantial enrichment for proteins involved in auxin, abscisic acid, ethylene, and brassinosteroid signaling, peroxisome function, disease resistance, protein phosphorylation and light perception, including the phytochrome （Phy） A and phototropin photoreceptors. Soon after red-light treatment, PhyA becomes the dominant ubiquitylated species, with ubiquitin attachment sites mapped to six lysines. A PhyA mutant protected from ubiquitin addition at these sites is substantially more stable in planta upon photoconversion to Pfr and is hyperactive in driving photomorphogenesis. However, light still stimulates ubiquitylation and degradation of this mutant, implying that other attachment sites and/or proteolytic pathways exist. Collectively, we expand the catalog of ubiquitylation targets in Arabidopsis and show that this post- translational modification is central to the rewiring of plants for photoautotrophic growth.

关键词： Arabidopsis ubiquitin mass spectrometry photomorphogenesis phytochrome degradation

A Review of Deepwater Pipeline Construction in the U.S. Gulf of Mexico-Contracts, Cost, and Installation Methods

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j.urnal of Marine Science and Application 2016年第3期15卷 288-306页

作者： mark j. Kaiser Center for Energy Studies Louisiana State University Baton Rouge 70803 USA

The offshore pipeline network in the U.S. Gulf of Mexico is the largest and most transparent system in the world. A review of deepwater proj.cts in the region provides insight into construction cost and installation methods and the evolution of contract strategies. Pipeline proj.cts are identified as export systems, infield flowline systems, and combined export and infield systems, and three dozen deepwater pipeline installations from 1980–2014 are described based on Offshore Technology Conference(OTC) and Society of Petroleum Engineers(SPE) industry publications and press release data. Export lines and infield flowlines are equally represented and many proj.cts used a combination of j.lay, S-lay and reel methods with rigid steel, flexible line, and pipe-in-pipe systems. The average 2014 inflation-adj.sted cost for pipeline proj.cts based on OTC/SPE publications was $2.76 million/mi and ranged from $520 000/mi to $12.94 million/mi. High cost pipelines tend to be short segments or specialized pipeline. Excluding the two cost endpoints, the maj.rity of proj.cts ranged from $1 to $6 million/mi. The average inflation-adj.sted cost to install deepwater pipelines in the U.S. Gulf of Mexico based on available public data is estimated at $3.1 million/mi.

关键词： construction cost contract type empirical statistics installation methods deepwater pipeline review

Robust Adaptive Model Tracking for Distributed Parameter Control of Linear Infinite-dimensional Systems in Hilbert Space

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IEEE/CAA j.urnal of Automatica Sinica 2014年第3期1卷 294-301页

作者： mark j.Balas Susan A.Frost the Embry-Riddle Aeronautical University the NASA Ames Research Center

This paper is focused on adaptively controlling a linear infinite-dimensional system to track a finite-dimensional reference *** a linear continuous-time infinite-dimensional plant on a Hilbert space with disturbances of known waveform but unknown amplitude and phase,we show that there exists a stabilizing direct model reference adaptive control law with the properties of certain disturbance rej.ction and *** plant is described by a closed,densely defined linear operator that generates a continuous semigroup of bounded operators on the Hilbert space of *** central result will show that all errors will converge to a prescribed neighborhood of zero in an infinitedimensional Hilbert *** result will not require the use of the standard Barbalat’s lemma which requires certain signals to be uniformly *** result is used to determine conditions under which a linear infinite-dimensional system can be directly adaptively controlled to follow a reference *** particular,we examine conditions for a set of ideal traj.ctories to exist for the tracking *** results are applied to adaptive control of general linear diffusion systems described by self-adj.int operators with compact resolvent.

关键词： Adaptation models Adaptive control Hilbert space Learning (artificial intelligence) Robustness Traj.ctory adaptive control algorithm adaptive theory distributed parameter system Distributed parameter systems Hilbert space traj.ctory Adaptation models reference model adaptive control Robustness Computer algorithms

Are sperm capacitation and apoptosis the opposite ends of a continuum driven by oxidative stress？

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Asian j.urnal of Andrology 2015年第4期17卷 633-639页

作者： Robert j.Aitken mark A Baker Brett Nixon Priority Research Centre in Reproductive Science Discipline of Biological Sciences and Hunter Medical Research Institute University of Newcastle NSW 2308 Australia.

This chapter explores the possibility that capacitation and apoptosis are linked processes j.ined by their common dependence on the continued generation of reactive oxygen species （ROS）. According to this model capacitation is initiated in spematozoa following their release into the female reproductive tract as a consequence of intracellular ROS generation, which stimulates intracellular cAMP generation, inhibits tyrosine phosphatase activity and enhances the formation of oxysterols prior to their removal from the sperm surface by albumin. The continued generation of ROS by capacitating populations of spermatozoa eventually overwhelms the limited capacity of these cells to protect themselves from oxidative stress. As a result the over-capacitation of spermatozoa leads to a state of senescence and the activation of a truncated intrinsic apoptotic cascade characterized by enhanced mitochondrial RO$ generation, lipid peroxidation, motility loss, caspase activation and phosphatidylserine externalization. The latter may be particularly important in instructing phagocytic leukocytes that the removal of senescent, moribund spermatozoa should be a silent process unaccompanied by the generation of proinflammatory cytokines. These observations reveal the central role played by redox chemistry in defining the life and death of spermatozoa. A knowledge of these mechanisms may help us to engineer novel solutions to both support and preserve the functionality of these highly specialized cells.

关键词： apoptosis reactive oxygen species sperm capacitation

Three-dimensional steep wave impact on a vertical cylinder

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j.urnal of Hydrodynamics 2016年第4期28卷 523-533页

作者： Ioannis K.CHATj.GEORGIOU Alexander A.KOROBKIN mark j.COOKER School of Mathematics University of East Anglia School of Naval Architecture and Marine Engineering National Technical University of Athens

In the present study we investigate the 3-D hydrodynamic slamming problem on a vertical cylinder due to the impact of a steep wave that is moving with a steady *** linear theory of the velocity potential is employed by assuming inviscid,incompressible fluid and irrotational *** the problem is set in 3-D space,the employment of the Wagner condition is *** set of equations we pose,is presented as a mixed boundary value problem for Laplace＇s equation in *** from the mixedtype of boundary conditions,the problem is complicated by considering that the region of wetted surface of the cylinder is a set whose boundary depends on the vertical coordinate on the cylinder up to the *** make some simple assumptions at the start but otherwise we proceed *** find closed-form relations for the hydrodynamic variables,namely the time dependent potential,the pressure impulse,the shape of the wave front（from the contact point to beyond the cylinder） and the slamming force.

关键词： cylinder hydrodynamic incompressible steep Wagner employment otherwise coordinate analytically assumptions