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Sexual dimorphism in immune response： Testing the hypothesis in an insect species with two male morphs

Insect Science 2013年第5期20卷 620-628页

作者： Gloria Ruiz-Guzman Jorge Canales-Lazcano Jesus Guillermo Jimenez-Cortes Jorge Contreras-Garduno Centro de investigacion Sobre Enfermedades Infecciosas Instituto Nacional de Salud Publica Av. Universidad No. 655 C. P. 62100 Cuernavaca Morelos departamento de Biologia Divisi6n de Ciencias Naturales y Exactas Universidad de Guanajuato Guanajuato departamento de Ecologia Evolufiva Instituto de Ecologia Universidad Nacional Autonoma de Mexico Apdo. Postal 70-275 04510 Mexico D. F. Mexico

It has been proposed that given that males should invest in sexual traits at the expense of their investment in immune response, females are better immunocompetent than males. Typically, this idea has been tested in monomorphic species, but rarely has been evaluated in polymorphic male species. We used Paraphlebia zoe, a damselfly with two male morphs： the black-winged morph （Black-W） develop black spots as sexual traits and the hyaline-winged morph （Hyaline-W） resembles a female in size and wings color. We predicted that Black-W should have a lower immune response than Hyaline-W, but that the latter males should not differ from females in this respect. Nitric oxide （NO） and phenoloxidase （PO） production, as well as hemolymph protein content, were used as immune markers. Body size （wing length） was used as an indicator of the male condition. The results show that, as we predicted, females and Hyaline-W had higher values of NO than Black-W, corresponding to differences in size. However, the opposite was found in relation to PO production. Females had the highest levels of hemolymph protein content, whereas no differences were found between Black-W and Hyaline-W. These results partially support the sexual selection hypothesis and are discussed in the context of the life history of this species. Black-W, Hyaline-W, and females could express the immune markers that are prioritized by their particular condition, and probably neither of them could express all immune markers in an elevated manner, as this would result in an excessive accumulation of free radicals.

关键词： immune response male morphs Paraphlebia zoe polymorphic species,territoriality trade-off

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Analysis and parameter extraction of memristive structures based on Strukov's non-linear model

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Journal of Semiconductors 2018年第12期39卷 106-113页

作者： A.Avila Garcia L.Ortega Reyes Centro de investigacion y de Estudios Avanzados del instituto Polit6cnico Nacional Departamento de Ingenieria ElectricaSeccion de Electronica del Estado SolidoMexico 07360Mexico

Diverse models have been proposed for explaining the electrical performance of memristive devices. In principle, the behavior of internal variables associated to each one could be extracted from experimental results. In a former work, thermally grown TiOmemristive structures were built and characterized to obtain the constitutive relationship(magnetic flux versus charge). The aim of this work is to continue that analysis by determining the microscopic parameters within the frame of a simple model. We use the already obtained memristance dependence of time and the basic expressions from the non-linear model proposed by Strukov et al. to compute the state-variable,the mobility of the doping species, the speed of the boundary between the doped and the undoped regions, the voltages and the electric fields on the distinct regions. The power dissipation and its time evolution are also presented. Moreover, a quite different window function from those formerly proposed, which was estimated from experimental data, is also determined. This information provides a straightforward picture of the ionic transport during one cycle of a square voltage waveform within the framework of this simple model. Finally, a quality factor is proposed as the key parameter for actual memristors viewed under the same model.

关键词： memristors parameter extraction non-linear model experimental window function

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Phylogeography of SARS-CoV-2 pandemic in Spain:a story of multiple introductions,micro-geographic stratification,founder effects,and super-spreaders

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Zoological Research 2020年第6期41卷 605-620页

作者： Alberto Gomez-Carballa Xabier Bello Jacobo Pardo-Seco Maria Luisa Perez del Molino Federico Martinon-Torres Antonio Salas Unidade de Xendtica Instituto de Ciencias Forenses(I NCI FOR)Facultade de MedicinaUniversidade de Santiago de Compostelaand GenPoB Research GroupInstituto de Investigaci6n Sanitaria(IDIS)Hospital Clinico Universitario de Santiago(SERGAS)Galicia 15706Spain Genetics Vaccines and Pediatric Infectious Diseases Research Group(GENVIP)Instituto de Investigacion Sanitaria de Santiago(IDIS)and Universidade de Santiago de Compostela(USC)Galicia 15706Spain Translational Pediatrics and Infectious Diseases Department of PediatricsHospital Clinico Universitario de Santiago de Compostela(SERGAS)Galicia 15706Spain Servicio de Microbiologia y Parasitologia Complejo Hospitalario Universitario de Santiago de CompostelaSantiago de CompostelaGalicia15706 Spain

Spain has been one of the main global pandemic epicenters for coronavirus disease 2019(COVID-19).Here,we analyzed>41000 genomes(including>26000 high-quality(HQ)genomes)downloaded from the GISAID repository,including 1245(922 HQ)sampled in *** aim of this study was to investigate genome variation of novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and reconstruct phylogeographic and transmission patterns in *** analysis suggested at least 34 independent introductions of SARS-CoV-2 to Spain at the beginning of the *** lineages spread very successfully in the country,probably favored by super-spreaders,namely,A2 a4(7.8%),A2 a5(38.4%),A2 a10(2.8%),B3 a(30.1%),and B9(8.7%),which accounted for 87.9% of all genomes in the Spanish *** distinct feature of the Spanish SARS-Cov-2 genomes was the higher frequency of B lineages(39.3%,mainly B3 a+B9)than found in any other European *** B3 a,B9,(and an important sub-lineage of A2 a5,namely,A2 a5 c)most likely originated in Spain,the other three haplogroups were imported from other European *** B3 a strain may have originated in the Basque Country from a B3 ancestor of uncertain geographic origin,whereas B9 likely emerged in *** time of the most recent common ancestor(TMRCA)of SARS-CoV-2 suggested that the first coronavirus entered the country around 11 February 2020,as estimated from the TMRCA of B3 a,the first lineage detected in the ***,earlier claims that the D614 G mutation is associated to higher transmissibility is not consistent with the very high prevalence of COVID-19 in Spain when compared to other countries with lower disease incidence but much higher frequency of this mutation(56.4% in Spain vs.82.4% in rest of Europe).Instead,the data support a major role of genetic drift in modeling the micro-geographic stratification of virus strains across the country as well as the role of SARS-CoV-2 super-spreaders.

关键词： Covid-19 SARS-CoV-2 Genomics Phylogeny Phylogeography

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Dietary carbohydrate-to-protein ratio influences growth performance,hepatic health and dynamic of gut microbiota in atlantic salmon(Salmo salar)

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Animal Nutrition 2022年第3期10卷 261-279页

作者： Alejandro Villasante Carolina Ramírez Hector Rodríguez Patricio Dantagnan Adrian Hernandez Elías Figueroa Jaime Romero Facultad de Medicina Veterinaria y Agronomía Universidad de Las AmericasSantiagoChile Laboratorio de Biotecnología de Alimentos Unidad de AlimentosInstituto de Nutricion y Tecnología de Los Alimentos(INTA)Universidad de ChileSantiagoChile Programa de Anatomía y Biología del desarrollo Facultad de MedicinaUniversidad de ChileSantiagoChile Núcleo de investigacion en Produccion Alimentaria Facultad de Recursos NaturalesUniversidad Catolica de TemucoTemucoChile

Atlantic salmon(Salmo salar)fed a carbohydrate-rich diet exhibit suboptimal growth performance,along with other metabolic *** is well known that gut microbes play a pivotal role in influencing metabolism of the host,and these microbes can be modified by the *** main goal of the present study was to determine the effect of feeding graded levels of digestible carbohydrates to Atlantic salmon on the distal intestine digesta microbiota at 3 sampling times(i.e.,weeks 4,8 and 12),during a 12-week trial.A low carbohydrate-to-high protein diet(LC/HP,0%wheat starch),a medium carbohydrate-tomedium protein diet(MC/MP,15%wheat starch)or a high carbohydrate-to-low protein diet(HC/LP,30%wheat starch)was fed to triplicate fish tanks(27 to 28 fish per tank).We performed an in-depth characterization of the distal intestine digesta ***,growth parameters,liver histology and the expression of genes involved in hepatic neolipogenesis in fish were *** fed a HC/LP diet showed greater hepatosomatic and viscerosomatic indexes(P=0.026 and P=0.018,respectively),lower final weight(P=0.005),weight gain(P=0.003),feed efficiency(P=0.033)and growth rate(P=0.003)compared with fish fed the LC/HP ***,feeding salmon a high digestible carbohydrate diet caused greater lipid vacuolization,steatosis index(P=0.007)and expression of fatty acid synthase(fas)and delta-6 fatty acyl desaturase(d6fad)(P=0.001 and P=0.001,respectively)in the liver compared with fish fed the LC/HP ***,the major impact of feeding a carbohydrate-rich diet to Atlantic salmon in beta diversity of distal intestine digesta microbiota was observed at week 4(HC/LP vs MC/MP and HC/LP vs LC/HP;P=0.007 and P=0.008,respectively)and week 8(HC/LP vs MC/MP;P=0.04),no differences between experimental groups were detected after 12 weeks of ***,at the end of the trial,there was a negative correlation between lactic acid bacteria(LAB)members,including Leuconostoc and Lactobacil

关键词： Microbiota Microbiome Atlantic salmon Steatosis Lactic acid bacteria Probiotics

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Consolidation of AA 7075-2 wt% ZrO2 Composite Powders by Severe Plastic deformation via ECAP

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Acta Metallurgica Sinica(English Letters) 2016年第10期29卷 895-901页

作者： S. E. Hernandez-Martinez J. J. Cruz-Rivera R. Martinez-Sanchez C. G. Garay-Reyes J. A. Mufioz-Bolanos J. M. Cabrera J.L.Hernández-Rivera instituto de Metalurgia Universidad Autonoma de San Luis Potosi Sierra Leona 550 78210 San Luis Potosi Mexico Centro de investigacion en Materiales Avanzados (CIMAV) Miguel de Cervantes 120 31109 Chihuahua Mexico departamento de Ciencia de Materiales e Ingenieria Metalurgica Universitat Politecnica de Catalunya Av Diagonal 647 08028 Barcelona Spain Fundacion CTM Centro Tecnologico Plaza de la Ciencia 208243 Manresa Spain CONACYT Research Fellow-instituto de Metalurgia Universidad Autonoma de San Luis Potosi- Sierra Leona 550 78210 San Luis Potosf Mexico

The powders of the AA 7075-ZRO2 were mixed by mechanical milling, but it was found that the system presents a few disadvantages when processed by conventional sintering and hot extrusion, since intermetallic phases between ZrO2 particles and alloying elements were formed. Equal channel angular pressing （ECAP） processing was proposed as an alternative method to consolidate the composite where there is no intermetallic formation. The analysis of the ECAP process showed that the intermediate temperature （220℃） produced a higher consolidation level than conventional sintering and hot extrusion （400 and 500℃, respectively）. This fact was supported by relative density analysis. In the case of the sintered and hot-extruded sample, the relative density exhibited a value of 0.95, while ECAP sample showed a value of 0.98. Hardness values show that microstructural refinement obtained during mechanical milling was preserved during ECAP processing even when it was carded out at 220℃.

关键词： Metal matrix composites (MMCs) Powder consolidation Severe plastic deformation (SPD)

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Occult hepatitis B virus infection among Mexican human immunodeficiency virus-1-infected patients

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World Journal of Gastroenterology 2014年第37期20卷 13530-13537页

作者： Ma Teresa Alvarez-Muoz Angelica Maldonado-Rodriguez Othon Rojas-Montes Rocio Torres-Ibarra Fernanda Gutierrez-Escolano Guillermo Vazquez-Rosales Alejandro Gomez Onofre Muoz Javier Torres Rosalia Lira Unidad de investigacion Medica en Enfermedades Infecciosas y Parasitarias Hospital de PediatriaCentro Medico Nacional Siglo XXIInstituto Mexicano del Seguro Social Clinica de Hepatitis Hospital de Infectologia Centro Médico Nacional La Raza Hospital General Regional No.72 IMSS Unidad de investigacion Medica en Enfermedades Infecciosas y Parasitarias Hospital de PediatriaCentro Medico Nacional Siglo XXIInstituto Mexi-cano del Seguro Social Hospital Infantil de Mexico "Federico Gomez"

AIM: To determine the frequency of occult hepatitis B infection (OHBI) in a group of human immunodeficiency virus (HIV)-1+/ hepatitis B surface antigen negative (HBsAg)- patients from Mexico.

关键词： Hepatitis B virus Occult hepatitis B virus infection Human immunodeficiency virus Hepatitis B surface antigen negative Risk factors Molecular diagnostics

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Glass formation,thermal and mechanical properties of ZrCuAlNi bulk metallic glasses

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Transactions of Nonferrous Metals Society of China 2018年第6期28卷 1157-1165页

作者： C.E.BORJA I.A.FIGUEROA O.LOZADA-FLORES M.ESTRADA G.A.LARA-RODRIGUEZ J.A.VERDUZCO instituto de investigacion en Metalurgia y Materiales Universidad Michoacana de San Nicolfis de Hidalgo (UMSNH)Fco. J. Mujica S/N Col. Felicitas del Rio C.P. 58030 Morelia Mich. Mexico instituto de investigaciones en Materiales Universidad Nacional Autonoma de Mdxico (UNAM) Circuito Exterior S/N Cd. Universitaria C.P. 04510 Cd. Mx. Mexico

The glass forming ability, thermal and mechanical properties of some Zr Cu Al Ni bulk metallic glasses were analyzed. The compositions of the alloys were theoretically determined with the dense packing and kinetic fragility index models. Cylindrical and conical ingots were produced by copper mould suction-casting under Ar atmosphere. The conical ingots were characterized by means of X-ray diffraction in order to determine the glassy structure. It was found that both alloys have a critical glassy diameter, Dc, of 3 mm. Thermal behaviours were investigated by differential scanning calorimetry at heating rates of 0.5, 0.67 and 0.83 K/s. The gamma parameter γ, supercooled liquid region ΔTx, and reduced glass transition temperature Trg, of the experimentally obtained glasses indicated high glass forming ability. The glassy compositions showed a fragility index of ~40 GPa. The compression test of the investigated alloys was carried out at a strain rate of 0.016 s^-1, obtaining a elastic modulus of ~83 GPa, total deformation of ~5%, yield strength of 1.6 GPa and hardness of 4 GPa. It was concluded that the use of the dense packing and kinetic fragility index models helped to predict glass-forming compositions in the family alloy investigated.

关键词： bulk metallic glass glass formation ability fragility index packing efficiency suction casting

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A functional variant in the CD209 promoter is associated with DQ2-negative celiac disease in the Spanish population

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World Journal of Gastroenterology 2006年第27期12卷 4397-4400页

作者： C Nú■ez B Rueda A Martínez C Maluenda I Polanco MA López-Nevot E Ortega E Sierra E Gómez de la Concha E Urcelay J Martín Servicio de Inmunología Clínica Hospital Clínico San CarlosMadridSpain instituto de Parasitología y Biomedicina "López Neyra" CSICGranadaSpain Servicio de Pediatría Hospital Clínico San CarlosMadrid Spain Servicio de Gastroenterología y Nutrición Pediátrica Hospital La PazMadridSpain Servicio de Inmunología Hospital Virgen de las NievesGranadaSpain Servicio de Pediatría Hospital Virgen de las NievesGranadaSpain Centro de investigaciones Biológicas CISCMadridSpain

AIM： To address the role of CD209 in celiac disease （CD） patients. Non-human leukocyte antigen （HLA） genetic factors in CD predisposition are poorly understood, and environmental factors like infectious pathogens may play a role. CD209 is a dendritic and macrophage surface molecule involved in pathogen recognition and immune activation. Recently, a functional variant in the promoter of the CD209 gene （-336A/G） has been shown to affect the transcriptional CD209 activity in vitro and it has been associated with a higher susceptibility to/or severity of infection. METHODS： The study population was composed of two case-control cohorts of 103 and 386 CD patients and 312 y 419 healthy controls as well as a panel of 257 celiac families. Genotyping for the -336A/G CD209 promoter polymorphism was performed using a TaqMan 5＇ allelic discrimination assay. HLA-DQ was determined by hybridization with allele specific probes. RESULTS： Initially, the case-control and familial studies did not find any association of the -336 A/G CD209 genetic variant with CD susceptibility. However, the stratification by HLA-DQ2 did reveal a significant association of CD209 promoter polymorphism in the HLA-DQ2 （-） group （carrier A vs GG in DQ2 （-） vs DQ2 （＋） patients （P = 0.026, OR = 3.71）. CONCLUSION： The -336G CD209 allele seems to be involved in CD susceptibility in HLA-DQ2 （-） patients. Our results might suggest a possible role of pathogens in the onset of a minor group of CD patients.

关键词： CD209 HLA-DQ2 Celiac disease Single nucleotide polymorphism Susceptibility

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Effects of corn gluten feed inclusion at graded levels in a corn-soybean diet on the ileal and fecal digestibility of growing pigs

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Journal of Animal Science and Biotechnology 2015年第1期6卷 63-68页

作者： Gerardo Mariscal Landin Tercia Cesaria Reis de Souza Ericka Ramirez Rodriguez Centro Nacional de investigacion en Fisiologia Animal Instituto Nacional de Investigaciones Forestales Agricolas y PecuariasKm 1Carretera a ColonAjuchitlan ColonQueretaro 76280Mexico Facultad de Ciencias Naturales Universidad Autonoma de QueretaroSantiago de QueretaroAv.De las Ciencias s/n Juriquilla 76000QueretaroQueretaroMexico

Background： This study aimed to determine the effect of the inclusion of corn gluten feed （CGF） on the apparent and standardized ileal digestibility of protein and amino acids and the apparent ileal and total tract digestibility of energy in growing pigs. The study was performed using 16 barrows （weight, 45.3 ±4.5 kg） that were fitted with a T cannula at the terminal ileum. There were four treatments： a corn-soybean diet without CGF and three corn-soybean diets containing increasing levels of CGF （65, 130, and 195 g/kg）. Data were analyzed according to a randomized complete block design, four blocks with four pigs each （one pig per treatment）. The trend of the response （linear or quadratic） was determined using orthogonal contrasts, and when a linear effect was determined, a linear equation was obtained. Results： The results showed that the inclusion up to 195 g/kg of CGF in the corn-soybean diet did not diminish the ileal digestibility （apparent and standardized） of protein and amino acids （P 〉 0.05）, except that of phenylalanine, cystine, and proline. A linear decrease （P 〈 0.05） per gram of CGF added to the diet in the apparent and standardized ileal digestibility of phenylalanine （0.011 and 0.015 percentage units, respectively）, cystine （0.048 and 0.043 percentage units, respectively）, and proline （0.045 and 0.047 percentage units, respectively） was noted. Similarly, ileal digestibility of dry matter and energy were adversely affected （reduced by 0.028 and 0.025 percentage units, respectively, per gram of CGF increment in the diet）. A significant （P 〈 0.05） linear reduction in total tract digestibility with increase in CGF amount in the diet was observed for energy （0.027 percentage units）, dry matter （0.027 percentage units）, crude protein （0.020 percentage units）, and neutral detergent fiber （0.041 percentage units） per gram of CGF added to the diet. Conclusion： CGF did not affect the ileal digestibility of protein and most amino acids but reduced the ileal an

关键词： Amino acids Corn gluten feed Energy Ileal digestibility Pigs Total tract digestibility

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Conflictive management of small mammals considered as pests： A long way to evidence-based policy making

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Current Zoology 2012年第2期58卷 353-357页

作者： Catarina FERREIRA Miguel deLIBES-MATEOS instituto de investigacion en Recursos Cinegeicos IREC （CSIC-UCLM-JCCM） Ronda de Toledo s/n E-13071 Ciudad Real SPAIN CIBIO Centro de Investigacao em Biodiversidade e Recursos Geneticos Campus Agrario de Vairao 4485-661 Vairao PORTUGAL

This paper discusses the controversial management decisions made by policy-makers worldwide regarding poisoning campaigns aimed to control small mammal populations, often considered harmful economic pests. Aside from considerations re- garding the biological consequences of these campaigns, we argue that when society rejects all values of science and expertise then only badly supported and negligent decisions will be made about conservation and management issues. The extermination of small mammal species, some of which play crucial ecological roles in several regions of the world, is just an example of such discredit and misinformation. Without a strong commitment towards evidence-based policy-making, economic investments in re- search and development could be entirely compromised

关键词： Evidence-based policy Pest management Poisoning campaigns Small mammals

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