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The implementation and data analysis of an interferometer for intense short pulse laser experiments

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High Power Laser Science and Engineering 2016年第3期4卷 60-66页

作者： Jaebum Park hector A.Baldis Hui Chen Lawrence Livermore National Laboratory University of California

We present an interferometry setup and the detailed fringe analysis method for intense short pulse(SP) laser *** interferometry scheme was refined through multiple campaigns to investigate the effects of pre-plasmas on energetic electrons at the Jupiter Laser Facility at Lawrence Livermore National Laboratory. The interferometer used a frequency doubled(λ=0.527 μm) 0.5 ps long optical probe beam to measure the pre-plasma density, an invaluable parameter to better understand how varying pre-plasma conditions affect the characteristics of the energetic electrons. The hardware of the diagnostic, data analysis and example data are presented. The diagnostic setup and the analysis procedure can be employed for any other SP laser experiments and interferograms, respectively.

关键词： Mach-Zehnder interferometer optical interferometry picosecond probe plasma density short pulse laser

A study of process-induced grain structures during steady state and non-steady state electron-beam welding of a titanium alloy

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Journal of Materials Science & Technology 2022年第18期113卷 117-127页

作者： Yu Lu Richard Turner Jeffery Brooks hector Basoalto School of Metallurgy and Materials University of BirminghamBirminghamB152TTUnited Kingdom Department of Materials Science and Engineering The University of SheffieldMappin StreetSheffieldS13JDUnited Kingdom

A detailed microstructural characterisation of the emerging weld-line grain structure,for bead-upon-plate welds in Ti-6Al-4V(Ti64)of differing plate thickness,was *** microstructure studied was formed during both steady state and non-steady state sections within the weld path,with the non-steady state portion being taken from the end of the plate as the weld bead and heat source overhang the edge of the *** allows for the effects of welding process conditions on the microstructural evolution to be *** weld pool geometry and 3D tomography of the weld-induced defects have been *** characterisation of microstructure and texture for different welding parameters and for steady and non-steady states have been used to identify physical parameters for the microstructure predictions that are difficult to obtain *** different states significantly affect the weld crown shape and formation,weld toe,weld bead depth and ***,the heat affected zone(HAZ)re-mains *** the microstructural evolution,both the steady and non-steady states have similar microstructure and *** defects were observed in the steady state section of welds,but sub-surface spherical pores have been observed in the non-steady state section of a *** element modelling to simulate the thermal-metallurgical-mechanical fields within the steady and non-steady state sections of the welds was considered,and the cooling rates predicted within steady state and non-steady sections were interrogated to improve the theoretical understanding of the microstructure and defect formation differences in these Ti64 EB weld regions.

关键词： Electron-beam fusion welding Processing Microstructure Ti-6Al-4V

Radicals and Kothe’s Conjecture for Skew PBW Extensions

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Communications in Mathematics and Statistics 2021年第2期9卷 119-138页

作者： Armando Reyes hector Suarez Departamento de Matematicas Universidad Nacional de ColombiaSede BogotaColombia Escuela de Matemáticas y Estadística Universidad Pedagogica y Tecnológica de ColombiaSede TunjaColombia

The aim of this paper is to investigate different radicals(Wedderburn radical,lower nil radical,Levitzky radical,upper nil radical,the set of all nilpotent elements,the sum of all nil left ideals)of the noncommutative rings known as skew Poincare–Birkhoff–Witt *** characterize minimal prime ideals of these rings and prove that the Kothe’s conjecture holds for these ***,we establish the transfer of several ring-theoretical properties(reduced,symmetric,reversible,2-primal)from the coefficients ring of a skew PBW extension to the extension itself.

关键词： Armendariz rings Kothe’s conjecture Skew PBW extensions

Tales of the Tail and Sperm Head Aches --Changing concepts on the prognostic significance of sperm pathologies affecting the head, neck and tail

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Asian Journal of Andrology 2012年第1期14卷 14-23,174页

作者： hector E Chemes Cristian Alvarez Sedo Laboratory of Testicular Physiology and Pathology Center for Research in Endocrinology National Research Council （CONICET） Endocrinology Division Buenos Aires Children＇s Hospital Gallo 1330 C1425SEFD Buenos Aires Argentina Centro de Estudios en Ginecologia y Reproduccion （CEGyR） C1425SEFD Buenos Aires Argentina

This article presents an update on the variable prognostic significance of different sperm pathologies in patients with severe male factor infertility due to morphology and motility disorders. Severe asthenozoospermia is one of the leading causes of male infertility as spermatozoa cannot reach the oocyte and/or penetrate normally. Identifying structural causes of sperm immotility was of great concern before the advent of intracytoplasmic sperm injection （ICSI）, because immotility was the limiting factor in the treatment of these patients. In these cases, in vitro methods are used to identify live spermatozoa or stimulate sperm motility to avoid selection of non-viable cells. With these advances, fertilization and pregnancy results have improved dramatically. The identification of genetic phenotypes in asthenozoospermia is important to adequately inform patients of treatment outcomes and risks. The one sperm characteristic that seriously affects fertility prognosis is teratozoospermia, primarily sperm head and neck anomalies. Defects of chromatin condensation and acrosomal hypoplasia are the two most common abnormalities in severe teratozoospermia. The introduction of microscopic methods to select spermatozoa and the development of new ones to evaluate sperm quality before ICSI will assure that ultrastructural identification ofsperm pathologies will not only be of academic interest, but will also be an essential tool to inform treatment choice. Herein, we review the differential roles played by sperm components in normal fertilization and early embryo development and explore how assisted reproductive technologies have modified our concepts on the prognostic significance of sperm pathologies affecting the head, neck, mid-piece and tail.

关键词： acrosomal hypoplasia chromatin anomalies fertility prognosis intracytoplasmic sperm injection intracytoplasmic injection of morphologically selected spermatozoa sperm neck defects sperm pathologies tail abnormalities teratozoospermia

State Estimation Using Non-uniform and Delayed Information: A Review

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International Journal of Automation and computing 2018年第2期15卷 125-141页

作者： Jhon A.Isaza hector A.Botero Hernan Alvarez Universidad Nacional de Colombia Research group on dynamic processes-Kalman Group

The study and application of methods for incorporating nonuniform and delayed information in state estimation tech- niques are important topics to advance in soft sensor development. Therefore, this paper presents a review of these methods and pro- poses a taxonomy that allows a faster selection of state estimator in this type of applications. The classification is performed according to the type of estimator, method, and used tool. Finally, using the proposed taxonomy, some applications reported in the literature are de- scribed.

关键词： State estimation asynchronism delayed measurement non-uniform information taxonomy.

Distribution,Properties,Land Use and Management of Mollisols in South America

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Chinese Geographical Science 2011年第5期21卷 511-530页

作者： Artigas Duran hector Morris Guillermo Studdert LIU Xiaobing Key Laboratory of Mollisols Agroecology Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Harbin 150081 China Faculty of Agronomy Garzon 780 12900 Montevideo Uruguay Institute of Soils INTA-CIRN CC 25 (1712) Castelar Buenos Aires Argentina Faculty of Agricultural Sciences National University of Mar Del Plata CC 276 (B7620WAP) Balcarce Buenos Aires Argentina

Mollisols are common in South America. They cover about 8.87 × 107ha, 1.3 × 107ha and 4.3 × 106ha in Argentina, Uruguay and Southern Brazil respectively, which is 11.5% of the world total. Most of South American Mollisols were developed on Pleistocene and Holocene sediments and lie within the limits of the temperate zone, though the extreme north is bordering subtropical and the extreme south is within a cold-temperate zone. All suborders of Mollisols occur in Argentina, the most extensive being Udolls followed by Ustolls, whereas only Udolls, Aquolls and Albolls occur in Uruguay. Vertisols in Uruguay have many properties similar to Mollisols, and the occurrence of Vertisols is strongly associated with Mollisols. The Pampean Mollisols are a significant component of the global breadbasket of modem times. The main Argentine crops are wheat, corn, sorghum, barmy, soybeans and sunflower, while Mollisols in Uruguay remain mostly dedicated to cattle and sheep grazing though crop production has been increasing very rapidly in the last decade. Throughout South America, research has shown that Mollisols are experiencing losses of soil organic matter and nutrients, and degradation of physical properties after long cropping periods, resulting in soil scientists calling for increased conservation practices to reduce future losses and a deterioration of soil quality, and thus a more sustainable agriculture in the region.

关键词： Mollisols classification sustainability soil fertility no tillage South America

Intragastric injection of botulinum toxin for the treatment of obesity. Where are we?

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World Journal of Gastroenterology 2008年第12期14卷 1805-1809页

作者： Diego Garcia-Compean hector Maldonado Garza Department of Gastroenterology Faculty of Medicine University Hospital. Ave Madero y Gonzalitos Col Mitras Centro Monterrey 64700 Mexico

Obesity has reached epidemic proportions particularly in western countries. Most non-surgical treatments of this condition are disappointing. Since 2005, several studies evaluating the effect of Botulinum Toxin type A (BT-A) in gastric antrum by means of endoscopy for the treatment of obesity have been published. This treatment modality was based on the observation that gastric injection of BT-A in laparatomized rats induced a significant reduction of food intake and body weight. Nowadays, 6 studies have been published yielding conflicting results. Differences in selection of patients, doses of BT-A, method of administration of the toxin and instruments of evaluation of some parameters among these studies may be the cause of divergent results. We discuss herein some important features of these studies pointing out on differences among them. At the same time, based on the knowledge of physiological characteristics of normal and abnormal gastric function related with feeding, we discuss the probable causes of failure observed in these trials. Finally, we give some guidelines concerning the way that future research in this field may follow, not without calling attention to disadvantages of this treatment.

关键词： Botulinum toxin Obesity Gastric emptying Gastric motility Gastroparesis

Maneuvering Angle Rigid Formations With Global Convergence Guarantees

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IEEE/CAA Journal of Automatica Sinica 2022年第8期9卷 1464-1475页

作者： Liangming Chen Zhiyun Lin hector Garcia de Marina Zhiyong Sun Mir Feroskhan School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore Department of Computer Architecture and Technology and also with CITICUniversity of Granada18014 GranadaSpain Department of Electrical Engineering Eindhoven University of Technology5600 MB Eindhoventhe Netherlands

Angle rigid multi-agent formations can simultaneously undergo translational,rotational,and scaling maneuvering,therefore combining the maneuvering capabilities of both distance and bearing rigid ***,maneuvering angle rigid formations in 2D or 3D with global convergence guarantees is shown to be a challenging problem in the existing literature even when relative position measurements are *** by angle-induced linear equations in 2D triangles and 3D tetrahedra,this paper aims to solve this challenging problem in both 2D and3D under a leader-follower *** the 2D case where the leaders have constant velocities,by using local relative position and velocity measurements,a formation maneuvering law is designed for the followers governed by double-integrator *** the leaders have time-varying velocities,a sliding mode formation maneuvering law is proposed by using the same *** the 3D case,to establish an angle-induced linear equation for each tetrahedron,we assume that all the followers'coordinate frames share a common Z ***,a formation maneuvering law is proposed for the followers to globally maneuver Z-weakly angle rigid formations in *** extension to Lagrangian agent dynamics and the construction of the desired rigid formations by using the minimum number of angle constraints are also *** examples are provided to validate the effectiveness of the proposed algorithms.

关键词： Index Terms—Angle rigid formations formation control formation maneuvering global convergence multi-agent systems

Current protective strategies in liver surgery

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World Journal of Gastroenterology 2010年第48期16卷 6098-6103页

作者： Kurinchi S Gurusamy hector D Gonzalez Brian R Davidson HPB and Liver Transplantation Royal Free CampusUniversity College London Medical SchoolRoyal Free Hospital

During liver resection surgery for cancer or liver transplantation,the liver is subject to ischaemia (reduction in blood flow) followed by reperfusion (restoration of blood flow),which results in liver injury [ischemiareperfusion (IR) or IR injury]. Modulation of IR injury can be achieved in various ways. These include hypothermia,ischaemic preconditioning (IPC) (brief cycles of ischaemia followed by reperfusion of the organ before the prolonged period of ischaemia i.e. a conditioning response),ischaemic postconditioning (conditioning after the prolonged period of ischaemia but before the reperfusion),pharmacological agents to decrease IR injury,genetic modulation of IR injury,and machine perfusion (pulsatile perfusion). Hypothermia decreases the metabolic functions and the oxygen consumption of organs. Static cold storage in University of Wisconsin solution reduces IR injury and has prolonged organ storage and improved the function of transplanted grafts. There is currently no evidence for any clinical advantage in the use of alternate solutions for static cold storage. Although experimental data from animal models suggest that IPC,ischaemic postconditioning,various pharma-cological agents,gene therapy,and machine perfusion decrease IR injury,none of these interventions can be recommended in clinical practice. This is because of the lack of randomized controlled trials assessing the safety and efficacy of ischaemic postconditioning,gene therapy,and machine perfusion. Randomized controlled trials and systematic reviews of randomized controlled trials assessing the safety and efficacy of IPC and various pharmacological agents have demonstrated biochemical or histological improvements but this has not translated to clinical benefit. Further well designed randomized controlled trials are necessary to assess the various new protective strategies in liver resection.

关键词： Liver Hepatectomy Liver transplantation Ischemia-reperfusion injury Hypothermia Ischaemic preconditioning