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Host-parasite interactions in perpetual darkness:macroparasite diversity in the cavefish Astyanax mexicanus

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Zoological Research 2023年第4期44卷 782-792页

作者： Ana Santacruz David Hernández-mena Ramses miranda-Gamboa Gerardo Pérez-ponce De León Claudia Patricia Ornelas-García Departamento de Zoología Instituto de BiologíaUniversidad Nacional Autónoma de MéxicoMéxico City CP 04510México Departamento de Sistemas y Procesos Naturales Escuela Nacional de Estudios Superiores Unidad MéridaUcúYucatán CP 97357México Instituto de Energías Renovables Universidad Nacional Autónoma de MéxicoTemixcoMorelos CP 62580México Colección Nacional de Peces Departamento de ZoologíaInstituto de BiologíaUniversidad Nacional Autónoma de MéxicoMéxico City CP 04510México Stowers Institute for medical Research Kansas CityMO 64110USA

Astyanax mexicanus has repeatedly colonized cave environments,displaying evolutionary parallelisms in many troglobitic *** being a model system for the study of adaptation to life in perpetual darkness,the parasites that infect cavefish are practically *** this study,we investigated the macroparasite communities in 18 cavefish populations from independent lineages and compared them with the parasite diversity found in their sister surface fish populations,with the aim of better understanding the role that parasites play in the colonization of new *** the cavefish populations,we identified 13 parasite taxa,including a subset of 10 of the 27 parasite taxa known for the surface *** infecting the cavefish belong to five taxonomic groups,including trematodes,monogeneans,nematodes,copepods,and *** are the most dominant group,found in 14 *** macroparasites include species with direct life cycles and trophic transmission,including invasive ***,paired comparisons indicate higher parasite richness in the cavefish than in the surface *** variation in parasite composition across the caves suggests historical and geographical contingencies in the host-parasite colonization process and potential evolution of local *** base-line data on parasite diversity in cavefish populations of *** provides a foundation to explore the role of divergent parasite infections under contrasting ecological pressures(cave *** environments)in the evolution of cave adaptive traits.

关键词： Adaptation metazoan parasites Niche change Parasite assemblage Prevalence

The animal cachexia score(ACASCO)

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Animal models and Experimental medicine 2019年第3期2卷 201-209页

作者： Angelica Betancourt Sílvia Busquets marta ponce míriam Toledo Joan Guàrdia‐Olmos maribel Peró‐Cebollero Francisco J.López‐Soriano Josep m.Argilés Cancer Research Group Departament de Bioquímica i Biomedicina MolecularFacultat de BiologiaUniversitat de BarcelonaBarcelonaSpain Institut de Biomedicina de la Universitat de Barcelona BarcelonaSpain Advanced Statistical Data Analysis Applied to Psychology Departament de Metodologia de les Ciències del ComportamentFacultat de PsicologiaUniversitat de BarcelonaBarcelonaSpain Institut de recerca en Cervell Cogniciói Conducta(IR3C)BarcelonaSpain

Background:None of the published studies involving cancer cachexia experimental models have included a measure of the severity of the syndrome like the scoring system previously developed for human *** aim of the present investigation was to define and validate a cachexia score usable in both rat and mouse tumor ***:In order to achieve this goal,we included in the study one rat model(Yoshida AH‐130ascites hepatoma)and two mouse models(Lewis lung carcinoma and Colon26 carcinoma).The Animal cachexia score(ACASCO)includes five components:(a)body and muscle weight loss,(b)inflammation and metabolic disturbances,(c)physical performance,(d)anorexia,and(e)quality of life measured using discomfort symptoms and behavioral ***:Using the ACASCO values,three cut‐off values were estimated by applying hierarchical cluster *** groups were originally described,one exactly below the observed mean,a second exactly over the mean,and two other groups adjusted to every cue(inferior and superior).The three cut‐off values were estimated through maximization of the classification *** was accomplished by using a similarity matrix based on the metric properties of the variables and assuming multinormal *** results show that the four groups were:no cachexia,mild cachexia,moderate cachexia and advanced ***:The results obtained allow us to conclude that the score could be very useful as an endpoint in pre‐clinical studies involving therapeutic strategies for cancer *** potential usefulness of ACASCO relates to the primary endpoint in pre‐clinical cancer cachexia drug evaluations.

关键词： anorexia cachexia classification physical performance quality of life score wasting weight loss

Comparison on morphological and Optical Properties of TiO_(2) Thin Films Grown by Single-Pulse and multi-Pulse Laser Ablation

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Journal of Surface Engineered materials and Advanced Technology 2015年第1期5卷 17-23页

作者： Yonic Penaloza-mendoza Luis ponce-Cabrera Instituto Politecnico Nacional Cicata AltamiraAltamiraMéxico

TiO2 thin films were prepared on glass substrates using the PLD (Pulsed Laser Deposition) technique. In order to carry out the ablation process, a Nd:YAG laser was used emitting in 1064 nm wavelength at 10 Hz repetition rate, set up for operating in both single-pulse and multi-pulse regimes. A comparison of the deposition rate, the optical and morphological properties of the layers obtained from both ablation regimes was made, which showed that the multi-pulsed ablation produced layers with a higher surface quality and better optical properties.

关键词： Pulsed Laser Deposition Single-Pulse Ablation multi-Pulse Ablation TiO_(2) Thin Film

monitoring the Laser Ablation Process of Paint Layers by PILA Technique

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Open Journal of Applied Sciences 2016年第9期6卷 626-635页

作者： Angel Eduardo Villarreal-Villela L. ponce Cabrera Instituto Politécnico Nacional Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada Unidad Altamira Altamira México

The spectrum analysis obtained by Fast Fourier Transform of the Photoacoustic In-duced by Laser Ablation (PILA) during laser assisted paints removal process is de-scribed, in order to identify the presence of paint components on a metallic surface, optimize the ablation rate and propose the method as a cleaning process monitoring. The process was carried out using a low-cost experimental setup which includes a burst-mode Nd:YAG laser, an electret microphone, an audio amplifier device and an oscilloscope, to record the acoustic pulse and analyze it. The samples surface mor-phology was characterized by Optical microscopy and Optical Coherence Tomography (OCT) before and after irradiation to visualize the formation of craters. As additional monitoring technique, the Laser Induced Breakdown Spectroscopy (LIBS) was used. The potential of the analysis for qualitative monitoring of coating removal was demonstrated due to the coincidence of the information provided by LIBS and PILA techniques.

关键词： Laser Induced Breakdown Spectroscopy Pulsed Laser Nd:YAG Acousto-Optical Signal Processing

RANS simulations of the U and V grooves effect in the subcritical flow over four rotated circular cylinders

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Journal of Hydrodynamics 2015年第4期27卷 569-578页

作者： ALONZO-GARCIA A. GUTIERREZ-TORRES C.del C. JImENEZ BERNAL J.A. mOLLINEDO-ponce de LEON H.R. mARTINEZ-DELGADILLO S.A. BARBOSA-SALDANA J.G. Instituto Politécnico Nacional SEPI ESIME ZacatencoLABINTHAP U.P.Adolfo López Mateos Edif.5 3er.PisoMéxicoD.F.México Instituto Politécnico Nacional UPIITAAv.IPN 2580C.P.07340MéxicoD.F.México Universidad Autónoma metropolitana-Azcapotzalco Depto.Ciencias BásicasAv.San Pablo 180Azcapotzalco C.P 07740MéxicoD.F.México

This paper presents a CFD study about the effect of the V and U grooves in the flow over four cylinders in diamond shape configuration at subcritical flow conditions（Re= 41 000）. The k- ε Realizable turbulence model was implemented to fully structured hexahedral grids with near-wall refinements. Results showed that the numerical model was able to reproduce the impinging flow pattern and the repulsive forces present in the lateral cylinders of the smooth cylinder array. As a consequence of the flow alignment induced by the grooves, a jet-flow is formed between the lateral cylinders, which could cause an important vortex induced vibration effect especially in the rear cylinder. The magnitudes of the shear stresses at the valleys and peaks for the V grooved cylinders were lower than those of the U grooved cylinders, but the separation points were delayed due the U grooves presence. It is discussed the presence of a blowing effect caused by counter-rotating eddies located near the grooves peaks that cause a decrease of the shear stresses in the valleys, and promote them at the peaks.

关键词： RANS model grooved cylinder four cylinders subcritical flow impinging flow

Extraterrestrial microspherules from Bajada del Diablo,Chubut,Argentina

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Geoscience Frontiers 2017年第1期8卷 137-149页

作者： m.J.Orgeira L.N.Castro G.A.Goldmann C.B.Prezzi E.Sileo D.R.Vega C.Franzosi R.D.Acevedo O.martinez J.Rabassa J.F.ponce O.R.Tofalo Departamento de Ciencias Geologicas-lGEBA Facultaci de Ciencias Exactas y NaturalesOniversidad de Buenos AiresCiudad UniversitariaPabelldn 11C1428EHABuenos AiresArgentina Consejo Nacional de lnvestigaciones Cientificas y Tecnicas de Argentina CONICEE Argentina Departamento de lngenierfa Agrfcola y Uso de la Tierra Facultad de AgronomiaUniversidad de Buenos AiresAv.San Martin 4453CI417DSEBuenos AiresArgentina INQUImAE Departamento de Qufmica Inorganica.Analitica y Quimica Fisica.Facultad de Ciencias Exactas y Naturales.Universidad de Buenos AiresPabellon IICiudad Universitaria.C1428EHABuenos Aires.Argentina Gerencia de lnvestigacion y Aplicaciones Comision Nacional de Energfa AtomicaUniversidad Nacional General San MartinBuenos AiresArgentina Centro Austral de lnvestigaciones Cientificas CADIC-ConicetUshuaiaArgentina Universidad Nacional de la Patagonia"San Juan Bosco"Sede Esquel ChubutArgentina Universidad Nacional de la Patagonia"San Juan Bosco"Sede Ushuaia UshuaiaArgentina

The Quaternary infilling of a circular structure located in Bajada del Diablo,Chubut Province,Argentina has been proposed as a crater strewn field in previous *** we report the finding of about 65 microspherules collected in a trench excavated in the center of the *** majority of handpicked specimens are single,but some of them exhibit compound *** single specimens are spherical with a mean size of 137 nm,whereas the more complex samples show peduncles and drop *** crystal growth is recognized in the internal structure of some broken *** chemical composition from the surface and center of microspherules was determined by energy dispersive spectrometry employing *** EmPA and XRD analysis indicate that the microspherules are mainly composed of Fe and O with magnetite,Fe0with subordinate *** consideration of possible anthropogenic and volcanic origins,these spherulites are ascribed to an extraterrestrial *** accumulation rate of 47 microspherules per m2/yr is estimated for the studied *** value is two orders of magnitude higher than the reference flux for cosmic dust estimated for the last 1 ma in the Transantarctic *** microspherules might have been generated as a byproduct of asteroid entry in the atmosphere.

关键词： Extraterrestrial microspherules Chemistry Bajada del Diablo Chubut Patagonia-Argentina

Impact of overgrazing on the transmission of Echinococcus multilocularis in Tibetan pastoral communities of Sichuan Province,China

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Chinese medical Journal 2007年第3期120卷 237-242页

作者： WANG Qian XIAO Yong-fu Dominique A Vuitton Peter m Schantz Francis Raoul Christine Budke maiza Campos-ponce Philip S Craig Patrick Giraudoux Sichuan Centre for Disease Control and Prevention Chengdu610041 China WHO Collaborating Centre for the Prevention and Treatment ofAlveolar Echinococcosis SERF and LBE Usc INRA ResearchUnits University of Franche-Comte 25030-Besancon France Institute of Parasitology University of Zurich Winterthurerstrasse266a CH-8057 Zurich Switzerland Faculty of Earth and Life Sciences Free University AmsterdamNetherlands Cestode Zoonoses Research Group Bioscience Research Instituteand School of Environment and Life Sciences University ofSalford Salford MS4WT United Kingdom

Background Overgrazing was assumed to increase the population density of small mammals that are the intermediate hosts of Echinococcus multilocularis, the pathogen of alveolar echinococcosis in the Qinghai Tibet Plateau. This research tested the hypothesis that overgrazing might promote Echinococcus multilocularis transmission through increasing populations of small mammal, intermediate hosts in Tibetan pastoral communities. methods Grazing practices, small mammal indices and dog Echinococcus multilocularis infection data were collected to analyze the relation between overgrazing and Echinococcus multilocularis transmission using nonparametric tests and multiple stepwise logistic regression. Results In the investigated area, raising livestock was a key industry. The communal pastures existed and the available forage was deficient for grazing. Open （common） pastures were overgrazed and had higher burrow density of small mammals compared with neighboring fenced （private） pastures; this high overgrazing pressure on the open pastures measured by neighboring fenced area led to higher burrow density of small mammals in open pastures. The median burrow density of small mammals in open pastures was independently associated with nearby canine Echinococcus multilocularis infection （P=-0.003, OR=1.048）. Conclusion Overgrazing may promote the transmission of Echinococcus multilocularis through increasing the population density of small mammals.

关键词： echinococcosis, hepatic Echinococcus multilocularis overgrazing Tibetan pastoral communities

Organophosphate Pesticides in Coastal Lagoon of the Gulf of mexico

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Journal of Environmental Protection 2019年第2期10卷 103-117页

作者： Guadalupe ponce-Vélez Guadalupe de la Lanza-Espino Laboratorio de Contaminación marina Instituto de Ciencias del Mar y Limnología Universidad Nacional Autónoma de México Mexico City Méxio Laboratorio de Hidrobiología Instituto de Biología Universidad Nacional Autónoma de México Mexico City México

The worldwide use of semi-persistent organophosphate pesticides has become increasingly frequent and notorious. Their presence is registered in both continental and coastal waters;the latter ones are known for their subtly balanced environmental richness, difficult to recover once lost. These xenobiotics compounds reach the coastal zone through rivers that have crossed human settlements, as well as through peripheral run-off water used to exterminate agricultural pests. In mexico, a developing country, the use of pesticides for several decades has not been adequately regulated, which is why various coastal ecosystems are the accumulation areas of these agrochemicals used in the continent. In the Gulf of mexico, one of the coastal systems of high fishing importance for many years is the lagoon of Alvarado and receives the discharges of two great rivers, Blanco, Limón and Papaloapan, which travel more than 200 km from its source to the sea, crossing large extensions of farmland where there are also livestock activities and the use of these pesticides. For this reason, the objective of this work was to determine the presence of organophosphate pesticides in the Alvarado lagoon at the Gulf of mexico as a potential aspect of high impact contamination. Five pesticides have been identified in the lagoon sediments, of which the most important and highest concentrations are Dimethoate and Chlorpyrifos, with 75.65 - 79.0 ng/g and 0.17 - 0.23 ng/g respectively, both internationally classified as moderately toxic. These concentrations were comparable to levels in other world regions with intense agricultural activity and vector control like the mediterranean Sea and the lagoon of Alvarado was evidenced as a hot spot for the accumulation of these organophosphates with the high risk for the benthic organisms and for the human health when consuming these fishery products.

关键词： Organophosphate Pesticides Sediments Coastal Lagoon

On the Use of Laser Ablation for Cleaning High Voltage Ceramic Insulators

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Journal of Surface Engineered materials and Advanced Technology 2014年第5期4卷 257-261页

作者： E. de Posada L. moreira m. Arronte L. ponce T. Flores IPN CICATA ALTAmIRA km 14.5 Carretera Tampico-Puerto Industrial Altamira Altamira México

High voltage lines are one of the main ways for carrying electric energy. To do so high voltage insulators are needed to insulate these lines from the supporting towers. Glass, ceramic and polymer insulators are widely used. Generally high voltage insulators are exposed to weather where humidity, from rain and moist, together with pollution allows accumulation of unwanted material on the surface of the insulator. Cleaning procedures are then needed to remove such material and avoid short-circuiting. The most commonly used cleaning methods are hand cleaning using chemicals that need turning off the main and water jet, which allows keeping the line in service. In this work we explore the possibility of using laser ablation for cleaning high voltage ceramic insulators. It is demonstrated that cleaning can be accomplished by a two-step process. First a Q-switched Nd: YAG laser is used to ablate the unwanted material. The second step is to use a free running Nd: YAG laser to restore the surface hydrophobicity of ceramic insulator, which is affected in the first process step.

关键词： Laser Processing Surface Cleaning Hydrophobicity