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Mitochondrial phylogeography and molecular evolution of the rhodopsin visual pigment in troglobitic populations of Astyanax mexicanus(De Filippi,1853)

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Zoological research 2023年第4期44卷 761-775页

作者： Marco A.A.Garduño-Sánchez Vladimir de Jesus-Bonilla Silvia Perea ramses Miranda-Gamboa Andrea Herrera-García mauricio de la Maza Benignos Claudia Patricia Ornelas-García Colección Nacional de Peces Departamento de ZoologíaInstituto de BiologíaUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoC.P.04510México Posgrado en Ciencias Biológicas Colección Nacional de PecesDepartamento de ZoologíaInstituto de BiologíaUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoC.P.04510México Licenciatura en Ciencias Forenses Facultad de MedicinaUniversidad Nacional Autónoma de MéxicoCiudad UniversitariaCoyoacánMéxico CityC.P.04510México Instituto de Energías renovables Universidad Nacional Autónoma de MéxicoTemixcoMorelos C.P.62580Mexico Facultad de Ciencias Biológicas Universidad Autónoma de Nuevo LeónCiudad UniversitariaSan Nicolás de los GarzaNuevo LeónC.P.66450México

Cave-adapted animals provide a unique opportunity to study the evolutionary mechanisms underlying phenotypic,metabolic,behavioral,and genetic evolution in response to cave *** Mexican tetra(Astyanax mexicanus)is considered a unique model system as it shows both surface and cave-dwelling *** date,at least 33 different cave populations have been identified,with phylogenetic studies suggesting an origin from at least two independent surface lineages,thereby providing a unique opportunity to study parallel *** the present study,we carried out the most exhaustive phylogeographic study of *** to date,including cave and surface localities,using two mitochondrial markers(cytochrome b(cyt b)and cytochrome c oxidase subunit I(COI))and nuclear rhodopsin visual pigment(rho).Additionally,we inferred the molecular evolution of rho within the two contrasting environments(cave and surface)and across three geographic regions(Sierra de El Abra,Sierra de Guatemala,and Micos).In total,267 individuals were sequenced for the two mitochondrial fragments and 268 individuals were sequenced for the rho visual pigment from 22 cave and 46 surface *** results based on the mitochondrial data supported the two-lineage hypothesis,except for the Pachón and Chica caves,whose introgression has been largely *** Sierra de El Abra region depicted the largest genetic diversity,followed by the Sierra de Guatemala *** the phylogeographic patterns of rho,we recovered exclusive haplogroups for the Sierra de El Abra(Haplogroup I)and Sierra de Guatemala regions(Haplogroup IV).Moreover,a 544 bp deletion in the rho gene was observed in the Escondido cave population from Sierra de Guatemala,reducing the protein from seven to three intramembrane *** change may produce a loss-of-function(LOF)but requires further *** nonsynonymous(dN)and synonymous(dS)substitution rates(omega valuesω),our results revealed

关键词： Visual pigments Selection Cavefish Vision loss Loss of function

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通过组织结构调整进行有效决策的研究——孚宝中国案例

通过组织结构调整进行有效决策的研究——孚宝中国案例

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作者： mauricio Genis Padilla 华东理工大学

学位级别：硕士

孚宝是全世界领先的提供石油化工产品储藏服务的机构,在全世界设有办事处和服务终端。2008年孚宝亚洲取得很大的增长,增长尤其来自于中国区。孚宝中国由一个独立的管理部门及各服务终端构成,服务终端直接向总部进行汇报。为了避免一些... 详细信息

孚宝是全世界领先的提供石油化工产品储藏服务的机构,在全世界设有办事处和服务终端。2008年孚宝亚洲取得很大的增长,增长尤其来自于中国区。孚宝中国由一个独立的管理部门及各服务终端构成,服务终端直接向总部进行汇报。为了避免一些通用风险,在位于上海的管理部门的指导下,公司评估了整个战略和业绩,认为决策方法有待改变,以使组织结构成为以决策为导向的协作形式。本论文研究了中国区的这一决策管理结构模型的重组。在新的结构下所有的服务终端与新的管理部门呈网状进行协作。公司以此举措坚持其“投资并建立一个成熟强大而有雄心的组织机构”的战略,并以此增强沟通和交流。我们通过rAPID矩阵这一创新的决策过程来定义并划分各服务终端的角色和职责,并用来评估各职责部门的主要流程。目的在于更好的履行战略,更快的定位工作流程并解决公司瓶颈。rAPID将详细阐述组织内的责任承担,各用一个字母代表如下的组织内角色： ●r-recommend取得并分析信息,负责对关键决策进行提案的人。 ●A-Agree决定被执行前必须取得该人的同意。 ●P-Perform将决定付诸实施的人。 ●I-Input可以提供相关信息帮助r,使其提出更好的方案。 ●D-Decide对决定做最终决断并确定组织将付诸实施此决定的人。

关键词：孚宝中国决策组织结构 rAPID 战略

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Prevalence of Gastrointestinal Parasites in Horses of Central Mexico

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Open Journal of Veterinary Medicine 2020年第8期10卷 117-125页

作者： Camilo romero rafael Heredia Laura Miranda mauricio Arredondo DErMAVET Veterinary Hospital Iztapalapa Mexico City Mexico CIVET Veterinary Integral Center Animal Health and Welfare Ecatepec Estado de Mexico Mexico Universitary Center UAEM Amemeca Autonomous University of Mexico State Estado de Mexico Mexico Guanajuato University Irapuato-Salamanca Campus Life Sciences Division Irapuato Guanajuato Mexico

Equines are affected by a large number of endoparasites, these can cause gastrointestinal signs, respiratory, poor performance, slow growth and even cause sudden death. The presence of parasites can be associated with various factors related to the animal and environmental or geographical factors. The prevalence of gastrointestinal parasite infection and risk factors in horses were evaluated. Stool samples belonging to 218 horses from different regions of central Mexico were analyzed by coproparasitological concentration-flotation technique. The fecal examinations were carried out from February to August in 2017. Among the 218 samples that were examined, 103 (47.24%) were found to be positive with several gastrointestinal parasites, with Strongylus spp. being the most prevalent (23.85%) followed by Trichostrongylus spp. (21.56%) and Parascaris spp. (11.93%). Breed and place of origin were significantly associated with helminth infection. Sex was associated as a significant risk factor (p Strongylus spp. on females and by Anoplocephalardana;">, on males. In central Mexico, gastrointestinal helminth infection appears to be relatively low.

关键词： Gastrointestinal Helminths Prevalence Horses Parasites risk Factors

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cAMP:A second messenger involved in the mechanism of midgut alkalinization in Lutzomyia longipalpis

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Insect Science 2022年第4期29卷 1059-1070页

作者： Denise Barguil Nepomuceno Grasielle Caldas D’Ávila Pessoa Leonardo Barbosa Koerich Marcos Horácio Pereira mauricio roberto Viana Sant'Anna ricardo Nascimento Araújo Nelder Figueiredo Gontijo Laboratório de Fisiologia de Insetos Hematófagos Departamento de Parasitologia/ICBUniversidade Federal de Minas GeraisBelo HorizonteMGBrazil

The sand fly Lutzomyia longipalpis is the main vector of Leishmania infantum in the *** sand flies ingest sugar-rich solutions and blood,which are digested in the *** of nutrients is an essential function performed by digestive enzymes,which require appropriate physiological *** of the main aspects that influence enzymatic activity is the gut pH,which must be tightly *** second messengers are frequently involved in the coordination of tightly regulated physiological events,we investigated if the second messenger cAMP would participate in the process of alkalinization in the abdominal midgut of female *** midguts containing the indicator dye bromothymol-blue,cAMP stimulated the alkalinization of the midgut *** another technique based on the use of fluorescein as a pH indicator,we propose that cAMP is involved in the alkalinization of the midgut by activating HCO3-transport from the enterocyte's cytoplasm to the *** results strongly suggested that the carrier responsible for this process would be a HCO3−/Cl−antiporter located in the enterocytes’apical *** promotes the release of alkalinizing hormones in the hemolymph;however,when the enzyme adenylyl cyclase,responsible for cAMP production,was inhibited,we observed that the hemolymph from blood-fed ***’females did not stimulate midgut *** result indicated that hormone-stimulated alkalinization is mediated by *** the present study,we provide evidences that cAMP has a key role in the control of intestinal pH.

关键词： abdominal midgut alkalinization cAMP HCO_(3)^(-)/Cl^(-)antiport hormone Lulcomyia longipalpis

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Pancreas Transplant Salvage by Proximal Loop Ileostomy and Distal Ileostotomy Tube for Duodenal Stump Leak after Enteric Conversion

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Surgical Science 2011年第1期2卷 1-4页

作者： Monroy-Cuadros mauricio rodriguez-Velez Cesar 不详

After pancreas transplantation, some patients with bladder drainage (BD) of the pancreatic duct will need to be converted to enteric drainage (ED) because of reflux pancreatitis, metabolic acidosis, and urological complications. However, ED is associated with higher rates of duodenal stump leak, intra-abdominal abscess, and peritonitis. In some cases of enteric anastomosis leakage, a primary repair can be attempted, but in more severe cases, graft pancreatectomy is indicated. We report one patient who received a combined kidney and pancreas transplant with BD of exocrine secretions, but who required ED conversion 6 years later because of persistent metabolic acidosis and adverse urological symptoms. However, a significant duodenal leak was discovered 4 days post-operatively. To salvage the transplanted pancreas, we performed a diverting loop ileostomy proximal to the entero-entero anastomosis and the distal section was drained retrogradely with an ileostostomy tube, allowing the area of the leak to heal. Three months later, the ileostomy was reversed without complications, the symptoms that led to the ED conversion resolved, and the kidney and pancreas allografts remain functional 48 months later. We suggest that this might be a method by which transplanted pancreas may be salvaged in the case of leakage after ED conversion.

关键词： Pancreas Transplant Conversion leak

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墨西哥水果与坚果出口贸易研究

墨西哥水果与坚果出口贸易研究

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作者： mauricio Bernal Espinosa 北京交通大学

学位级别：硕士

在2016年底,根据联合国UNCOMTrADE和ITC统计数据,墨西哥是全球第13大出口国家。墨西哥还是热带水果的主要生产国,其中包括番石榴,芒果,牛油果,菠萝等水果,并且该类产品的价值和出口量十年来一直持续增长,一直保持该国第十大出口产品,同... 详细信息

在2016年底,根据联合国UNCOMTrADE和ITC统计数据,墨西哥是全球第13大出口国家。墨西哥还是热带水果的主要生产国,其中包括番石榴,芒果,牛油果,菠萝等水果,并且该类产品的价值和出口量十年来一直持续增长,一直保持该国第十大出口产品,同时成为全球第四大出口国。但目前,该类产品的主要贸易目的地仍然是美国。墨西哥约83%的水果与坚果出口值输往美国。本文以墨西哥水果产品向世界的出口贸易为研究对象,利用2007-2016年间的数据,(1)描述了墨西哥向世界出口水果与坚果出口规模,并基于HS08章的分类进行了出口商品结构和地理分布的分析;(2)揭示了墨西哥在水果和坚果出口类别中在世界上的地位;利用全球市场份额、进口国市场份额和显示性比较优势(rCA)展示了墨西哥的出口竞争力(3)分析了影响墨西哥水果与坚果出口竞争力的影响因素,并利用计量模型分析各因素的影响方向和程度;(4)根据分析结果提出作者意见和建议。结果显示,墨西哥水果和坚果产业的出口商品结构相对单一;出口地理分布上过于依赖美国。在整个行业中,墨西哥的显示性比较优势逐渐扩大,然而在具体产品方面,优势出现下降,而且其目标出口市场需要多样化。

关键词：水果与坚果墨西哥出口竞争力显示性比较优势

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PPIs are not associated with a lower incidence of portal-hypertension-related bleeding in cirrhosis

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World Journal of Gastroenterology 2010年第46期16卷 5869-5873页

作者： mauricio Garcia-Saenz-de-Sicilia Francisco Sanchez-Avila Norberto C Chavez-Tapia Gustavo Lopez-Arce Sandra Garcia-Osogobio roberto ruiz-Cordero Felix I Tellez-Avila Department of Gastroenterology Instituto Nacional de Ciencias Medicas y Nutrición Salvador ZubiranMexico CityMexico Medica Sur Clinic and Fundation Endoscopy Department Instituto Nacional de Ciencias Medicas y Nutricion Salvador ZubiranMexico City14000Mexico

AIM:To determine if proton pump inhibitor use in cirrhotic patients with endoscopic findings of portal hypertension is associated with a lower frequency of gastrointestinal ***:Patients with cirrhosis and endoscopic findings related to portal hypertension,receiving or not receiving proton pump inhibitor (PPI) therapy,were included *** assigned patients to two groups:group 1 patients underwent PPI therapy and group 2 patients did not undergo PPI ***:One hundred and five patients with a median age of 58 (26-87) years were included,57 (54.3%) of which were *** varices were found in 82 (78%) patients,portal hypertensive gastropathy in 72 (68.6%) patients,and gastric varices in 15 (14.3%) *** therapy was used in 45.5% of patients (n=48).Seventeen (16.1%) patients presented with upper gastrointestinal bleeding;in 14/17 (82.3%) patients,bleeding was secondary to esophageal varices,and in 3/17 patients bleeding was attributed to portal hypertensive *** related to portal hypertension according to PPI therapy occurred in 18.7% (n=9) of group 1 and in 14% (n=8) of group 2 (odds ratio:0.83,95% confidence interval:0.5-1.3,P=0.51).CONCLUSION:Portal hypertension bleeding is not associated with PPI *** findings do not support the prescription of PPIs in patients with chronic liver disease with no currently accepted indication.

关键词： Drug prescription Liver cirrhosis Portal hypertension Proton pump inhibitors Upper gastrointestinal bleeding

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Neoarchean atmospheric chemistry and the preservation of S-MIF in sediments from the São Francisco Craton

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Geoscience Frontiers 2022年第5期13卷 207-226页

作者： Alice Bosco-Santos William Patrick Gilhooly Ⅲ Paola de Melo-Silva Fotios Fouskas Amaury Bouyon João Gabriel Motta mauricio rigoni Baldim Wendell Fabricio-Silva Pascal Philippot Elson Paiva Oliveira Department of Geology and Natural resources University of CampinasCampinasSP 13083855Brazil Department of Earth Sciences Indiana University-Purdue University IndianapolisIndianapolisINUSA Institut de Physique du Globe de Paris Universitéde ParisCNRS-UMR 715475005 Paris Cedex 05France Vizlab-X-reality and GeoInformatics Lab UNISINOSSão LeopoldoRS 93022-750Brazil Geosciences Department Federal University of Mato GrossoCuiabáMTBrazil Geosciences Institute University of BrasiliaBrasíliaDistrito Federal 70910-900Brazil Institute of Geography and Geology University of Würzburg97074 WürzburgGermany Géosciences Montpellier Universitéde MontpellierCNRSUniversitédes AntillesMontpellierFrance Institute of Astronomy Geophysicsand Atmospheric SciencesUniversity of São PauloRua do Matão 1226São PauloBrazil

Sulfur mass-independent fractionation(S-MIF)preserved in Archean sedimentary pyrite is interpreted to reflect atmospheric *** ranges in Δ^(33)S that expanded into larger fractionations leading up to the Great Oxygenation Event(GOE;2.45–2.2 Ga)are disproportionately represented by sequences from the Kaapvaal and Pilbara *** patterns of S-MIF attenuation and enhancement may differ from the timing and magnitude of minor sulfur isotope fractionations reported from other cratons,thus obscuring local for global sulfur cycling *** expanding the Δ^(33)S record to include the relatively underrepresented São Francisco Craton in Brazil,we suggest that marine biogeochemistry affected S-MIF preservation prior to the *** an early Neoarchean sequence(2763–2730 Ma)from the rio das Velhas Greenstone Belt,we propose that low δ^(13)Corg(ron formation reflect the marine diagenetic process of anaerobic methane *** overlying black shale(TOC up to 7.8%)with higher δ^(13)Corg(-33.4‰to-19.2‰)and expanded Δ^(33)S(2.3‰±0.8‰),recorded oxidative sulfur cycling that resulted in enhance preservation of S-MIF input from atmospheric sources of elemental *** sequence culminates in a metasandstone,where concomitant changes to more uniform δCorg(-30‰to--25‰),potentially associated with the ruBisCO I enzyme,and near-zero Δ^(33)S(-0.04‰to 0.38‰)is mainly interpreted as evidence for local oxygen *** placed in the context of other sequences worldwide,the rio das Velhas helps differentiate the influences of global atmospheric chemistry and local marine diagenesis in Archean biogeochemical *** data suggest that prokaryotic sulfur,iron,and methane cycles might have an underestimated role in pre-GOE sulfur minor isotope records.

关键词： S-MIF preservation Archean atmospheric chemistry GOE São Francisco Craton

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Non-saturation Throughput of S-ALOHA Using the Time-Scale Decomposition Technique

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Journal of Mechanics Engineering and Automation 2014年第2期4卷 116-122页

作者： Luis mauricio Gutierrez-Begovich Mario Eduardo rivero-Angeles SEPI ESCOM Mobile Computing Department National Polytechnique Institute (IPN) Mexico City 07738 Mexico Communication and Computer Network Laboratory Computing Research Center (CIC-IPN) National Polytechnique Institute(IPN) Mexico City 07738 Mexico

S-ALOHA （Slotted ALOHA） random access protocol is a widely used protocol mainly for the transmission of short packets in wireless networks. Most papers consider either an infinite population model where the impact of the backoff protocol cannot be adequately evaluated or a finite population model where the number of nodes is fixed. In this letter, a combination of both models is proposed using the time-scale decomposition technique. This methodology allows to study the system under more realistic conditions where the dynamics of users enter and leaving the system are reflected on the performance of the system as well as the impact of the backoff protocol. Also, it allows studying the system in non-saturation conditions. The proposed methodology divides the analysis in two parts： packet-level and connection-level. This analysis renders suitable results when the time scale of the packet level and connection level statistics is different. On the other hand, when these scales are similar, the proposed methodology is no longer suited.

关键词： S-ALOHA non-saturation conditions infinite and finite population model time-scale decomposition.

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Edaphoclimatic seasonal trends and variations of the Salmonella spp. infection in Northwestern Mexico

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Infectious Disease Modelling 2021年第1期6卷 805-819页

作者： Yasiri Mayeli Flores Monter Andrea Chaves Beatriz Arellano-reynoso Andres mauricio Lopez-Perez Humberto Suzan-Azpiri Gerardo Suzan Facultad de Medicina Veterinaria y Zootecnia Universidad Nacional Autonoma de MexicoMexico City04510Mexico Escuela de Biología Universidad de Costa RicaSan Jose11501-2060Costa Rica Department of Medicine and Epidemiology School of Veterinary MedicineUniversity of CaliforniaDavisCA95695United States Laboratorio de Ecología Universidad Autonoma de Queretaro76230Mexico

Currently,Salmonella *** the bacterium causing the highest number of food-borne diseases(FADs)in the *** is primarily associated with contaminated water used to that irrigates crops from intensive livestock ***,literature emphasizes that the reservoirs for Salmonella *** in wildlife and there are unconventional sources or secondary reservoirs,such as *** soil-borne diseases have not been modeled in spatial scenarios,and therefore it is necessary to consider soil and other climatic factors to anticipate the emergence of new strains or serotypes with potential threat to public and animal *** objective of this research was to investigate whether edaphic and climatic factors are associated with the occurrence and prevalence of Salmonella *** Northwestern *** estimated the potential distribution of Salmonella *** an interpolation method of unsampled kriging areas for 15 environmental variables,considering that these factors have a seasonal dynamic of change during the year and modifications in longer ***,a database was generated with human salmonellosis cases reported in the epidemiological bulletins of the National System of Epidemiological Surveillance(SIVE).For the Northwest region,there were 30,595 human cases of paratyphoid and other salmonellosis reported have been reported in Baja California state,71,462 in Chihuahua,and 16,247 in Sonora from 2002 to *** highest prevalence was identified in areas with higher temperatures between 35 and 37℃,and precipitation greater than 1000 *** edaphic variables limited the prevalence and geographical distribution of Salmonella spp.,because the region is characterized by presenting a low percentage of organic matter(≤4.3),and most of the territory is classified as aridic and xeric,which implies that the humidity comprises≤180 days a ***,the seasonal time series indicated that in the states of Baja California and Chihuahua the rainy quarter of

关键词： Potential distribution Soil Temperature Precipitation Salmonella spp

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