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normozoospermic versus teratozoospermic domestic cats： differential testicular volume, sperm morphometry, and subpopulation structure during epididymal maturation

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Asian Journal of Andrology 2016年第6期18卷 871-878页

作者： Miguel Angel gutierrez-Reinoso Manuel Garcia-Herreros national Secretariat of Higher Education Science Technology and Innovation (SENESCYT) Quito Ecuador

Teratozoospermia （〈40% morphologically normal spermatozoa/ejaculate） is a frequent phenomenon in feline species. This research was carried out to study the possible differences in testicular volume, differential sperm morphometric traits, and potential differences regarding the sperm subpopulational structure during epididymal sperm maturation in teratozoospermic feline donors. Epididymal sperm samples were collected from the caput （R1）, corpus （R2）, and cauda （R3） epididymidis in two donor groups （n： normozoospermic; T： teratozoospermic）. Aliquots were assessed for concentration, viability, motility, and acrosomal integrity. Sperm morphometric descriptors from CASA-Morph analysis were analyzed by the Principal Component Analysis （PCA） and clustering analyses. Irrespective of the group analyzed, PCA revealed two Principal Components （PCs） for each epididymal region explaining more than the 93% of the variance. Surprisingly, the number of subpopulations remained constant in regions R1-R2-R3 irrespective of the donor group analyzed. However, the distribution of these subpopulations was found to be structurally different and strongly influenced by the epididymal region and the donor group. In conclusion, testicular morphometry and the sperm subpopulation structure were different in n and T donors. The alterations in subpopulations during epididymal maturation could be used as a potential clinical indicator of teratozoospermic individuals since an important influence of teratozoospermia on sperm subpopulation structure has been demonstrated.

关键词： epididymis feline sperm morphometry sperm subpopulations teratozoospermia testicular volume

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Use of wild trout for PBDE assessment in freshwater environments: Review and summary of critical factors

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Emerging Contaminants 2015年第1期1卷 54-63页

作者： Juan M.Ríos nerina B.Lana Paula Berton néstor F.Ciocco Jorgelina C.Altamirano Laboratorio de Química Ambiental Instituto Argentino de NivologíaGlaciología y Ciencias Ambientales(IANIGLA)-CONICETMendozaP.O Box 1315500 MendozaArgentina Facultad de Ciencias Exactas y naturales Universidad Nacional de CuyoPadre J.Contreras 13005500 MendozaArgentina Instituto Argentino de Investigaciòn de ZonasÁridas(IADIZA)-COnICET MendozaP.O Box 5075500 MendozaArgentina

Certain wild animals represent sentinels to address issues related to environmental pollution,since they can provide integrative data on both pollutant exposure and biological *** their technological benefits,PBDEs are considered a threat to environmental health due to their persistence,toxicity,and capacity to be *** pollutants have been found geographically widespread in fish,particularly in predator species such as *** aim of this work is to critically review the applicability and usefulness of wild trout for assessing PBDEs in freshwater *** reports include data from highly industrialized areas as well as areas from remote regions with relatively low human activity,including European and north American great lakes and freshwater environments in Europe,Greenland,subarctic areas and Patagonia,respectively.A summary of relevant factors were grouped into organism-specific factors(food habits,age,size,lipid content,sex and reproduction,tissue type,mechanism of contaminant uptake and metabolism),and PBDE levels in the surrounding environment(sediment).Five wild trout species[rainbow trout(Oncorhynchus mykiss),brown trout(Salmo trutta),lake trout(Salvelinus namaycush),arctic char(Salvelinus alpinus),and brook trout(Salvelinus fontinalis)],collected worldwide within the 1994 to present time frame,were *** techniques(principal component analysis-PCA)and mapping approach,showed clear differences in geographic distribution patterns of PBDE levels in trout depending on the region studied:wild trout from European and north American great lakes have the highest PBDE *** pattern could be due to high industrial activity at these locations.A correlational approach used to explore intraspecific relationships between PBDE levels and morphometry,showed positive relationships only for brown ***,brown trout showed the highest trout-to-sediment ratios,which is suggestive of a relatively greater capa

关键词： Critical factors Freshwater environments PBDE Trout Global hotspots

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Interactome Analysis of Microtubule-targeting Agents Reveals Cytotoxicity Bases in normal Cells

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Genomics, Proteomics & Bioinformatics 2017年第6期15卷 352-360页

作者： Andres Julian gutierrez-Escobar Gina Mendez-Callejas Grupo de Investigaciones Biomedicas y Genetica Aplicada-GIBGA Universidad de Ciencias Aplicadas y Ambientales U.D.C.A.Bogota 111166Colombia

Cancer causes millions of deaths annually and microtubule-targeting agents （MTAs） are the most commonly-used anti-cancer drugs. However, the high toxicity of MTAs on normal cells raises great concern. Due to the non-selectivity of MTA targets, we analyzed the interaction net- work in a non-cancerous human cell. Subnetworks of fourteen MTAs were reconstructed and the merged network was compared against a randomized network to evaluate the functional rich- ness. We found that 71.4% of the MTA interactome nodes are shared, which affects cellular pro- cesses such as apoptosis, cell differentiation, cell cycle control, stress response, and regulation of energy metabolism. Additionally, possible secondary targets were identified as client proteins of interphase microtubules. MTAs affect apoptosis signaling pathways by interacting with client pro- teins of interphase microtubules, suggesting that their primary targets are non-tumor cells. The paclitaxel and doxorubicin networks share essential topological axes, suggesting synergistic effects. This may explain the exacerbated toxicity observed when paclitaxel and doxorubicin are used in combination for cancer treatment.

关键词： Cancer treatment Microtubule-targeting agentInteractome analysis Cancer biology Apoptosis

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Cooperating CoScheduling:A Coscheduling Proposal Aimed at non-Dedicated Heterogeneous nOWs

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Journal of Computer Science & Technology 2007年第5期22卷 695-710页

作者： Francesc Giné Francesc Solsona mauricio Hanzich Porfidio Hernández Emilio Luque Department of Computer Science Universitat de Lleida Spain Department of Computer Architecture & Operating Systems Universitat Autònoma de Barcelona Spain

Implicit coscheduling techniques applied to non-dedicated homogeneous networks Of Workstations （nOWs） have shown they can perform well when many local users compete with a single parallel job. Implicit coscheduling deals with minimizing the communication waiting time of parallel processes by identifying the processes in need of coscheduling through gathering and analyzing implicit runtime information, basically communication events. Unfortunately, implicit coscheduling techniques do not guarantee the performance of local and parallel jobs, when the number of parallel jobs competing against each other is increased. Thus, a low efficiency use of the idle computational resources is achieved. In order to solve these problems, a new technique, named Cooperating CoScheduling （CCS）, is presented in this work. Unlike traditional implicit coscheduling techniques, under CCS, each node takes its scheduling decisions from the occurrence of local events, basically communication, memory, Input/Output and CPU, together with foreign events received from cooperating nodes. This allows CCS to provide a social contract based on reserving a percentage of CPU and memory resources to ensure the progress of parallel jobs without disturbing the local users, while coscheduling of communicating tasks is ensured. Besides, the CCS algorithm uses status information from the cooperating nodes to balance the resources across the cluster when necessary. Experimental results in a non-dedicated heterogeneous nOW reveal that CCS allows the idle resources to be exploited efficiently, thus obtaining a satisfactory speedup and provoking an overhead that is imperceptible to the local user.

关键词： job scheduling non-dedicated and heterogeneous nOW computing resource allocation

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Genetic and epigenetic control of transfer cell development in plants

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Journal of Genetics and Genomics 2016年第9期43卷 533-539页

作者： Jing Yuan Perry Bateman Jose gutierrez-Marcos State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyChinese Academy of Sciences School of Life Sciences University of Warwick

The inter-cellular translocation of nutrients in plant is mediated by highly specialized transfer cells （TCs）. TCs share similar functional and structural features across a wide range of plant species, including location at plant exchange surfaces, rich in secondary wall ingrowths, facilitation of nutrient flow, and passage of select molecules. The fate of endosperm TCs is determined in the TC fate acquisition stage （TCF）, before the structure features are formed in the TC differentiation stage （TCD）. At present, the molecular basis of TC development in plants remains largely unknown. In this review, we summarize the important roles of the signaling molecules in different development phases, such as sugars in TCF and phytohormones in TCD, and discuss the genetic and epigenetic factors, including TC-specific genes and endogenous plant peptides, and their crosstalk with these signaling molecules as a complex regulatory network in regulation of TC develonment in olants.

关键词： Transfer cells Differentiation Signals and genes network

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Modulation of gastric accommodation by duodenal nutrients

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World Journal of Gastroenterology 2005年第31期11卷 4848-4851页

作者： mauricio Carrasco Fernando Azpiroz Juan-R. Malagelada Digestive System Research Unit

AIM： To determine the relative potency and contribution of intestinal nutrients to net gastric accommodative relaxation and conscious perception. METHODS： In 12 healthy subjects, we randomly tested duodenal loads of lipids and carbohydrates （12 mL administered in 4 rain） at various caloric concentrations （0.0125-0.8 kcal/mL） separated by 12-24 rain wash-out periods of saline infusion. Maximal gastric relaxation was induced at the end of each experiment by i.v glucagon （5 μg/kg）, as reference. The reflex gastric response was measured by a barostat, and symptom perception by a 0-6 score questionnaire. RESULTS： Upids induced a dose-response gastric relaxation with a steep and early rise. Maximal effect （179±42 mL relaxation） reached at a relatively low concentration （0.2 kcal/mL）, maximal lipid-induced relaxation was 61±6% of the glucagon effect. By contrast, duodenal infusion of carbohydrates induced weaker relaxation that became significant only at the high end of the physiological concentration range （65±14 ml with 0.8 kcal/mL）. Intestinal nutrient loads, either of lipid or carbohydrates, did not induce significant changes in perception （0.6±0.4 and 0.1±0.4 score increase for the highest concentrations, respectively）. COnCLUSIOn： Chyme entering the small bowel induces nutrient-spedfic gastric relaxatory reflexes by a physiologically saturable mechanism. normally, neither the intestinal nutrient load nor the gastric accommodative response is perceived.

关键词： Gastric accommodation Enterogastric reflex Postprandial symptoms Intestinal nutrients Gastric relaxation Gastric barostat Gut perception

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4TQS: Four Tiers OVER Quality of Sensing with Energy Improvement in Wireless Sensor network

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International Journal of Communications, network and System Sciences 2021年第7期14卷 95-118页

作者： Luis Orlando Philco Asqui néstor A. Zamora Cedeño Faculty of Technical Education for Development Catholic University Santiago de Guayaquil Guayaquil Ecuador

This paper presents four algorithms for QoSensing (4TQS) and routing on dynamics Wireless Sensor networks. Since many types of researches held on QoSensing improvement in terms of coverage and connectivity enhancement. In a WSn with a density of 120 static and 30 mobile nodes, the major power-consuming activities are mobility and communication. Such power constraint has a great effect on the node activities and the same network. We analyzed the occurrence of coverage holes which is, regions inside the area of interest that are void of operational nodes for sensing and/or routing purposes. 4TQS method shows clustering phase through neuro-fuzzy based affinity propagation nFAP, sleep scheduling phase with ESLS algorithm and the assist of coverage enhancement phase in which HAHP is involved. Routing phase and connectivity metrics are improved with DTMR algorithm. Involvement of four efficient algorithms results in improved QoSensing in WSn. We analyzed our proposed method in both Star and Mesh topology in order to evaluate the QoSensing metrics in both topologies. Our method shows promising results in QoSensing metrics or performance in dynamics WSns.

关键词： QoSensing 4Tiers Metrics Coverage Connectivity

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True grit: ingestion of small stone particles by hummingbirds in West Mexico

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Avian Research 2021年第4期12卷 739-749页

作者： Omar Maya-García mauricio Ortega-Flores Jorge E.Schondube Posgrado en Ciencias Biológicas Unidad de PosgradoCoordinación del Posgrado en Ciencias BiológicasUniversidad Nacional Autónoma de MéxicoEdificio D1er pisoCircuito de PosgradosCiudad UniversitariaDel.CoyoacánC.P.04510 México D.F.Mexico Laboratorio de Ecología Funcional Instituto de Investigaciones en Ecosistemas y SustentabilidadUniversidad Nacional Autónoma de MéxicoAntigua Carretera a Pátzcuaro No.8701Col.Ex Hacienda de San Joséde la HuertaC.P.58190 MoreliaMichoacánMexico

Background: Grit is used by birds mainly for grinding hard food items but can also serve a nutritional role as a source of minerals. Ingestion of grit by birds has been documented primarily in species that feed on seeds and *** feeding mainly on nectar and small arthropods, hummingbirds also ingest grit, but why they do so is unclear. We quantified the number of grit particles in the stomachs of six species of hummingbirds during an annual cycle in a seasonal ecosystem of West ***: We compared the number of grit particles in the stomachs of different hummingbird species(Mexican Violetear Colibri thalassinus, Amethyst-throated Mountaingem Lampornis amethystinus, White-eared Hummingbird Basilinna leucotis, Rivoli's Hummingbird Eugenes fulgens, Broad-tailed Hummingbird Selasphorus platycercus, and Rufous Hummingbird S. rufus), and between sex and age categories during the different seasons of a year. To deter-mine if grit was used to grind ingested arthropods, we examined the relationships between the number of grit parti-cles, the biomass of arthropods ingested, and their chitin ***: Although species did not differ in the number of grit particles in their stomachs, we found that grit was mostly ingested by female individuals, with only one male of one species(Mexican Violetear) presenting grit in its stomach. We also found that female hummingbirds had grit in their stomachs during the rainy and the cold-dry season(June-February) but not during the warm-dry season(March-May). Our analyses revealed no relationship between the number of grit particles and the amount of ingested arthropods and arthropod chitin content. However,high grit consumption was related to wasp ingestion on Mexican ***: Our results indicate that grit is used mainly by female hummingbirds. The seasonal variation in the ingestion of grit by female individuals suggests that it can be used to meet mineral requirements related to breed-ing;how

关键词： Arthropod chitin content Arthropod digestion Breeding season Mineral nutritional requirements

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Development of a Fast Fluid-Structure Coupling Technique for Wind Turbine Computations

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Journal of Power and Energy Engineering 2015年第7期3卷 1-6页

作者： Matias Sessarego néstor Ramos-García Wen Zhong Shen Department of Wind Energy Technical University of Denmark Lyngby Denmark

Fluid-structure interaction simulations are routinely used in the wind energy industry to evaluate the aerodynamic and structural dynamic performance of wind turbines. Most aero-elastic codes in modern times implement a blade element momentum technique to model the rotor aerodynamics and a modal, multi-body, or finite-element approach to model the turbine structural dynamics. The present paper describes a novel fluid-structure coupling technique which combines a three- dimensional viscous-inviscid solver for horizontal-axis wind-turbine aerodynamics, called MIRAS, and the structural dynamics model used in the aero-elastic code FLEX5. The new code, MIRAS- FLEX, in general shows good agreement with the standard aero-elastic codes FLEX5 and FAST for various test cases. The structural model in MIRAS-FLEX acts to reduce the aerodynamic load computed by MIRAS, particularly near the tip and at high wind speeds.

关键词： Fluid-Structure-Interaction Wind-Turbine Aero-Elasticity

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Emerging Players in the nitrate Signaling Pathway

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Molecular Plant 2017年第8期10卷 1019-1022页

作者： Grace Armijo Rodrigo A. gutierrez Departamento de Genetica Molecular y Microbiologia Facultad de Ciencias Biologicas FONDAP Center for Genome Regulation Pontificia Universidad Cat61ica de Chile Santiago 8331150 Chile Departamento de Genetica Molecular y Microbiologia Facultad de Ciencias Biologicas Millennium Nucleus Center for Plant Functional Genomics Pontificia Universidad Catolica de Chile Santiago 8331150 Chile

nitrogen （n）-based fertilizers are routinely used to increase agricultural productivity for both food and non-food uses of crops. Unfortunately, excess n fertilizers escape to the environment, leading to detrimental effects on the ecosystem and human health. Understanding how plants sense and respond to different n nutrients or metabolites to regulate metabolism, physiology, growth, and development is essential for sustained yields while reducing agriculture＇s environmental and economic costs.

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