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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

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Best Simultaneous Approximation to Totally Bounded Sequences in Banach Spaces

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Acta Mathematica Sinica,English Series 2008年第9期24卷 1541-1554页

作者： Genaro lopez Department of Mathematical Analysis University of SevillaSevillaSpain

This paper is concerned with the problem of best weighted simultaneous approximations to totally bounded sequences in Banach spaces. Characterization results from convex sets in Banach spaces are established under the... 详细信息

关键词： best simultaneous approximation characterization uniqueness uniform smoothness

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Experimental and Numerical Analysis of a PCM-Integrated Roof for Higher Thermal Performance of Buildings

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Journal of Thermal Science 2024年第2期33卷 522-536页

作者： SIMON François RUIZ-VALERO Letzai GIRARD Aymeric GALLEGUILLOS hector Centro de Desarrollo Urbano Sustentable(CEDEUS) Pontificia Universidad Católica de Chile7500000SantiagoChile Facultad de Ciencias e Ingeniería Pontificia Universidad Católica Madre y Maestra(PUCMM)10103Santo DomingoDominican Republic LMGC IMT Mines AlesUniv MontpellierCNRS30100AlèsFrance Facultad de Ingeniería y Ciencias Universidad Adolfo Ibañez2520000Viña del MarChile Centro de Desarrollo Energético Antofagasta(CDEA) Universidad de Antofagasta1240000AntofagastaChile

Phase change materials(PCMs) designate materials able to store latent *** change state from solid to liquid over a defined temperature *** process is reversible and can be used for thermo-technical *** present paper aims to study the thermal performance of an inorganic eutectic PCM integrated into the rooftop slab of a test room and analyze its potential for building thermal *** experiment is conducted in two test rooms in Antofagasta(Chile) during summer,fall,and *** PCM is integrated into the rooftop of the first test room,while the roof panel of the second room is a sealed air *** work introduces a numerical model,which is built using the finite difference method and used to simulate the rooms' thermal *** thermal simulations of the PCM room are performed for other Chilean locations to evaluate and compare the capability of the PCM panel to store latent heat thermal energy in different *** show that the indoor temperature of the PCM room in Antofagasta varies only 21.1℃±10.6℃,while the one of the air-panel room varies 28.3℃±18.5℃.Under the experiment's conditions,the PCM room's indoor temperature observes smoother diurnal fluctuations,with lower maximum and higher minimum indoor temperatures than that of the air-panel *** simulations in other cities show that the PCM panel has a better thermal performance during winter,as it helps to maintain or increase the room temperature by some degrees to reach comfort *** demonstrates that the implementation of such PCM in the building envelope can effectively reduce space heating and cooling needs,and improve indoor thermal comfort in different climates of Chile.

关键词： phase change material thermal energy storage building space heating and cooling energy efficiency designbuilder

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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.

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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

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Individual repeatability in timing and spatial flexibility of migration routes of trans-Saharan migratory raptors

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Current Zoology 2014年第5期60卷 642-652页

作者： Pascual lopez-lopez Clara GARCLA-RIPOLLES Vicente URIOS Vertebrates Zoology Research Group CIBIO Research Institute University ofAlicante Edificio Ciencias III Apdo. 99 E-03080Alicante Spain

Satellite-tracking technology has allowed scientists to make a quantum leap in the field of migration ecology. Nowadays, the basic description of migratory routes of many species of birds has been reported. However, the investigation of bird migration at individual level （i.e. repeatability in migratory routes and timing） still remains seldom explored. Here, we investigated repeated migratory trips of a trans-Saharan endangered migratory raptor, the Egyptian Vulture Neophron percnopterus, tracked by GPS satellite telemetry. We compared between- and within-individual variation in migratory routes and timing in order to assess the degree of repeatability （or conversely, the flexibility） in migration. To this end, we analysed a dataset of 48 trips （23 springs and 25 autumns） recorded for six adult birds during 2007-2013. Our results showed consistent migration timing at the individual level, both in spring and autumn. Interestingly, there was a high degree of flexibility in the routes followed by the same individual in different years, probably due to variations in meteorological conditions. Contrary to expectations of a faster migration in spring than in autumn owing to a time-minimization strategy for breeding, birds spent less time in autumn migration （13 ± 2 days, range = 9-18 d） than in spring migration （19 ± 3 days, range = 13-26 d）, which can be explained by differences in environmental con- ditions en route. Egyptian vultures showed a consistent clockwise loop migration through western Africa, following more easterly routes in autumn than in spring. Finally, our results provide supporting evidence of low phenotypic plasticity in timing of migration （i.e. strong endogenous control of migration） and high flexibility in routes [Current Zoology 60 （5）： 642-652, 2014].

关键词： Egyptian vulture Endogenous control GPS Loop migration Neophron percnopterus Random routes Satellite tracking Simulation

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Versatile chip-based nanoscopy becomes ready for histopathology assessment

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Light(Science & Applications) 2022年第5期11卷 730-732页

作者： Martin lopez-Garcia Natural and Artificial Photonic Structures Group International Iberian Nanotechnology LaboratoryBraga 4715-330Portugal

Nanoscopy is a mature technology used routinely in life science to obtain images well below the optical diffraction *** the use of nanoscopy in histopathology assessment is very limited mostly due to the low throughput of traditional nanoscopic *** far,Chip-nanoscopy,nanoscopy in which sample illumination is performed by an integrated photonic chip instead of bulk optics,has been shown to provide an enhanced field of view and throughput for cell ***,a new development shows that chip-nanoscopy also offers interesting progress for the study of histological samples offering a complementary technique to electron microscopy for histopathology assessment.

关键词： nanos offering illumination

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Morphisms and Elements of Group-like Type in Weak Multiplier Bialgebras

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Algebra Colloquium 2018年第1期25卷 107-132页

作者： Esperanza lopez-Centella Departamento de Didactica de la Matematica Universidad de Granada Facultad de Educacion Economfa y Tecnologfa de Ceuta

With the purpose of providing a categorical treatment of weak multiplier bialgebras （introduced by BShm, Gomez-Torrecillas and Ldpez-Centella in 2015）, an ap- propriate notion of morphism for these algebraic objects is proposed. This allows us to define a category wmb of （regular） weak multiplier bialgebras （with a right full comultipli- cation）, containing as a full subcategory the category wba of weak bialgebras defined by BShm, Gomez-Torrecillas and lopez-Centella in 2014. We present a great source of ex- amples of these morphisms proving that, under some assumption, a functor between small categories induces a morphism of this kind between the natural weak multiplier bialgebra structures carried by the linear spans of the arrow sets of the categories. We explore the notion of elements of group-like type in a weak multiplier bialgebra, proposing a definition in the line of the one by the aforementioned authors for weak bialgebras. We show a big number of its properties and provide more general versions of many results known in the context of weak bialgebras. In particular, in analogy with the classical bialgebra setting （where the set of group-like elements is a monoid）, we prove that the set of these elements possesses a structure of category.

关键词： weak multiplier bialgebra weak bialgebra category group-like element

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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

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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

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