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Effect of a single dose of malathion on spermatogenesisin mice

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Asian Journal of Andrology 2003年第2期5卷 105-107页

作者： eduardo Bustos-Obregón Patricio González-Hormazabal Biology of Reproduction Unit Program of Morphology ICBM Faculty of Medicine University of Chile Santiago ChileBiology of Reproduction Unit Program of Morphology ICBM Faculty of Medicine University of Chile Santiago Chile

Aim: To observe the acute effect of the organophosphorous insecticide malathion on testicular function in mice. Methods: The effects of a single dose of malathion [240 mg/kg (1/12 LD50)] on plasma acetylcholinesterase (ACE) activity, spermatozoa (epididymal cauda counts and teratozoospermia), testis and plasma testosterone concentration) were evaluated at day 1,8, 16, 35 and 40 after treatment. Results: The sperm count was decreased significantly 24 h after treatment and teratozoospermia was increased at day 35 and 40. The height of the seminiferous epithelium and the diameter of tubular lumen were decreased at day 8. The percentage of tubular blockade was increased between day 8 and 35. A decrease in testosterone plasma level was observed at day 16 after treatment. Conclusion: Malathion damages male reproduction. The depletion of seminiferous tubules and the increase in teratozoospermia may be a genotoxic damage to the renewing spermatogonia, but the possibility of spermatogenic/ spermiogenic disfunction due to a decrease in the plasma testosterone level can not be ruled out.

关键词： testicular toxin malathion seminiferous tubule testosterone

Colon Adenocarcinoma in a Retrograde Intussusception: A Case Report and Literature Review

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Open Journal of Gastroenterology 2024年第5期14卷 153-160页

作者： Carlos Hernández Brito Pedro Arredondo Ruiz Brenda Paola Sáenz Dávila Arsenio Torres Delgado Luis eduardo Méndez Turrubiates Luis Ángel Amezcua Toledo Omar Josué Herrera López Surgical Oncology Department Centro Oncol&#243gico Onkolid Veracruz Mexico Clinical Oncology Department Centro Oncol&#243gico Onkolid Veracruz Mexico General and Laparoscopic Surgery Corporativo M&#233dico-Quir&#250rgico Torres Veracruz Mexico Radiation Oncology Department Centro Oncol&#243gico Onkolid Veracruz Mexico Radiology Department Centro Oncol&#243gico Onkolid Veracruz Mexico Anatomical Pathology Department Centro Oncol&#243gico Onkolid Veracruz Mexico

Background: Intussusception is defined as a telescoping of a proximal gastrointestinal segment with its mesentery to a distal one, only 5% occur in adults and in colon the probability that it is caused by a malignant disease is up to 65%. Only 1% occurs in a retrograde manner, the rest occur in an anterograde manner. Aim: Describe the clinical presentation of an intussusception in the adult patient as well as its most frequent causes and possible complications that influence decision making for a definitive treatment. Case Presentation: A 66-year-old woman diagnosed with colon adenocarcinoma who underwent elective transverse colectomy and colonic anastomosis with an incidental finding of a transverse colon tumor in a retrograde intussusception was studied. Conclusion: In any adult patient with an intussusception especially in colon a neoplasia should be suspected and the affected segment should be resected without being reduced due to the risk of perforation and tumor dissemination.

关键词： Colon Cancer Colon Adenocarcinoma Colonic Intussusception Intussusception

Mapping aboveground biomass by integrating geospatial and forest inventory data through a k-nearest neighbor strategy in north Central Mexico

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Journal of Arid Land 2014年第1期6卷 80-96页

作者： Carlos A AGUIRRE-SALADO eduardo J TREVIO-GARZA Oscar A AGUIRRE-CALDERón Javier JIMnez-PREZ Marco A GOnZleZ-TAGle José R VALDZ-LAZALDE Guillermo SnCHEZ-DíAZ Reija HAAPAnEn Alejandro I AGUIRRE-SALADO Liliana MIRAnDA-ARAGón Faculty of Forest Sciences Autonomous University of Nuevo Leon Faculty of Engineering Autonomous University of San Luis Potosi Forestry Program Postgraduate College Haapanen Forest Consulting Faculty of Agronomy and Veterinary Autonomous University of San Luis Potosí

As climate change negotiations progress,monitoring biomass and carbon stocks is becoming an important part of the current forest ***,national governments are interested in developing forest-monitoring strategies using geospatial *** statistical methods for mapping biomass,there is a nonparametric approach called k-nearest neighbor(knn).We compared four variations of distance metrics of the knn for the spatially-explicit estimation of aboveground biomass in a portion of the Mexican north border of the intertropical *** derived,climatic,and topographic predictor variables were combined with the Mexican national Forest Inventory(nFI)data to accomplish the *** of distance metrics applied into the knn algorithm was evaluated using a cross validation leave-one-out *** results indicate that the Most Similar neighbor(MSn)approach maximizes the correlation between predictor and response variables(r=0.9).Our results are in agreement with those reported in the *** findings confirm the predictive potential of the MSn approach for mapping forest variables at pixel level under the policy of Reducing Emission from Deforestation and Forest Degradation(REDD+).

关键词： k-nearest neighbor Mahalanobis most similar neighbor MODIS BRDF-adjusted reflectance forest inventory the policy of Reducing Emission from Deforestation and Forest Degradation

Deadly oasis:Recurrent annihilation of Cretaceous desert bryophyte colonies;the role of solar,climate and lithospheric forcing

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Geoscience Frontiers 2021年第1期12卷 1-12页

作者： Juan Pedro Rodríguez-Lópeza eduardo Barrón Daniel Peyrot Gary B.Hughes Department of Geology.Faculty of Science.United Arab Emirates University.50009.Al Ain Abu DhabiUnited Arab Emirates Instituto Geológico y Minero de Espana(IGME) Ríos Rosas 23E-28003MadridSpain School of Earth and Environment University of Western Australia.6101CrawleyWestern AustraliaAustralia Centre for Energy Geosciences University of Western Australia.6101CrawleyWestern AustraliaAustralia Physics Department University of CaliforniaSanta BarbaraCA93106USA

Many oases(wet interdunes)are sedimentary systems characterized by high-frequency water-level oscillations,marked changes in salinity and intense biological activity at their *** are considered to be one of the most challenging environments on Earth for ecosystem *** dynamic,depositional settings are usually unfavourable for fossilization and subsequent preservation of vegetal *** paper describes bryophyte(liverwort)assemblages occurring in three successive horizons interpreted to represent(i)recurrent early successional phases of biological soil crust colonization of wet interdune margins or(ii)exceptional preservation of floating or riparian liverworts in oasis pond waters associated with a progressive fall of the interdune water *** record of in situ colonization surfaces characterized by delicate(***-free)three-dimensional structures represents an exceptional type of preservation herein associated with a rapid variation in phreatic interdune water level and the subsequent establishment of anoxic and reducing *** occurrence of exceptionally preserved liverwort colonies coincides with the sedimentary record of,at least,three seismite levels in the *** gathered from the site suggests that the water table of the oasis was controlled by a combination of(i)a positive creation of accommodation space due to subsidence associated with movement on syn-sedimentary extensional faults,and(ii)the rise and fall of the oasis water table controlled by the oscillations of the groundwater system due to orbital changes which appear to drive the variability of the climate *** groundwater levels flooded the oasis soil crusts and lead to the exceptional recurrent preservation of liverwort colonies at the oasis ***,considering the hypothesis of floating or riparian liverworts in the oasis pond waters,the fall in the level of the oasis water table placed the floating liverworts in contact with the

关键词： Oasis Cretaceous Liverworts Colonies Extensional tectonics Solar cyclicity

High-resolution patterns of palaeoenvironmental changes during the Little Ice Age and the Medieval Climate Anomaly in the northwestern Iberian Peninsula

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Geoscience Frontiers 2020年第5期11卷 1461-1475页

作者： Daniel Castro martin Souto Maria Isabel Fraga eduardo Garcia-Rodeja Sebastian Perez-Diaz Jose Antonio Lopez Saez Xabier Pontevedra-Pombal Dpto.Botanica Fac.BioloxiaUniversidade de Santiago de CompostelaGaliciaSpain Dpto.Edafoloxia e Quimica Agricola Fac.BioloxiaUniversidade de Santiago de CompostelaGaliciaSpain Dpto.Geografia Urbanismo y Ordenacion Del TerritorioETS CaminosCanales y PuertosUniversidad de CantabriaSpain GI Arqueobiologia Instituto de HistoriaCCHS–CSICMadridSpain

to identify plant macrofossils,estimate peat humification and calculate hydroclimatic indices based on current bog species,with the overall aim of determining the climate conditions associated with evolution of the bog during the Medieval Climate Anomaly and the Little Ice *** proxies,together with historical and climate data,proved to be good indicators of the changes in bog surface ***:of the core led to identification of 9 different periods:two corresponding to the so-called Medieval Climate Anomaly(930 to 1345 AD,1075–665 calibrated years before present[*** BP]);four corresponding to the Little Ice Age(1345 to 1905 AD;665–105 cal yr BP);and three corresponding to the last century(1905 to 2000 AD).The findings revealed a generally dry climate that lasted until the 14th century,followed by a transition to a long period with a more humid,but characteristically very variable climate,which ended at the beginning of the 20th century and was followed by a rapid transition to more humid conditions and finally,a change to drier *** Medieval Climate Anomaly was indicated by the abundance of dry-adapted mosses(leucobryum glaucum,Hypnum cupressiforme)and characterized by warm dry conditions and high levels of peat humification,with alternating wet *** LIA period was dated by a large abundance of Sphagnum species(an indicator of wetness)and a gradual increase in the humification ***,four different climate phases were differentiated in this ***-resolution reconstruction of the evolution of the CVM bog and the multiproxy approach have together enabled a more detailed identification of climatic variations in this area,which are generally consistent with the global models,as well as better definition of the elusive climatic oscillations in the last millennium and confirmation of the importance of local modulation of global *** study provides new information and a detailed chronology of climatic events that will hel

关键词： Last millennium Raised bog Plant macrofossil Humification analysis Southwest Europe Climate change

Variability in the Light Absorption Coefficient by Phytoplankton,non-Algal Particles and Colored Dissolved Organic Matter in the northern Gulf of California

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Open Journal of Marine Science 2018年第1期8卷 20-37页

作者： Stella P.Betancur-Turizo Adriana G.González-Silvera eduardo Santamaría-Del-Angel Roberto Millán-núnez eduardo Millán-núnez Héctor García-nava Víctor M.Godínez Laura Sánchez-Velasco Facultad de Ciencias Marinas Universidad Autonoma de Baja CaliforniaEnsenadaMéxico Grupo de Investigacion en Oceanología Facultad de Oceanografía FísicaEscuela Naval de Cadetes“Almirante Padilla”Barrio BosqueSector ManzanilloCartagena de IndiasColombia Departamento de Ecología Marina CICESEEnsenadaMéxico Instituto de Investigaciones Oceanológicas Universidad Autónoma de Baja CaliforniaEnsenadaMéxico Departamento de Oceanografía Física CICESEEnsenadaMéxico Departamento de Plancton y Ecología Marina CICIMAR-IPN.Av.Instituto Politécnico Nacional s/nLa PazMéxico

Variability of the optical properties of the northern Gulf of California (México) were analyzed for the first time based on six cruises performed from spring to summer (March to September) between 2008 and 2013. The changes observed in the absorption by three seawater components (phytoplankton, detritus and chromophoric dissolved organic matter or CDOM) were analyzed in relation to changes in bio-optical regions and composition of the phytoplankton community (determined based on phytoplankton pigments). Two regions with unique bio-optical characteristics were identified separated by a narrow transition zone: the Upper Gulf of California (UGC) and northern Gulf of California (nGC). Despite the temporal changes in their spatial distribution they maintained particular characteristic. UGC is characterized by an average Chla of 1.78 mg/m3, the dominance of microphytoplankton (diatoms and dinoflagellates) and a stronger contribution of detritus to total light absorption. nGC is characterized by an average Chla of 0.7 mg/m3 and the predominance of picophytoplankton, characterized by the dominance of zeaxanthin (marker pigment for cyanobacteria) and/or chlorophyll b (marker pigment for green algae), along with a co-dominium by CDOM and phytoplankton to light absorption. Results indicate that Case II waters can be very different when evaluating the individual contribution by phytoplankton, detritus and CDOM to total light absorption what has to be considered for the selection of bio-optical models for each specific region what can also help to a better definition of the related uncertainties.

关键词： Light Absorption Phytoplankton CDOM Detritus Ocean Color Gulf of California

Chaotic dynamics and coexistence in a three species interaction model

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International Journal of Biomathematics 2015年第2期8卷 135-159页

作者： eduardo Saez eduardo Stange Ivan Szanto eduardo Gonzalez-Olivares Manuel Falconi Departamento de Matematica Universidad Tecnica Federico Santa Maria Valparaiso Chile Instituto de Matemdticas Universidad de Valparaiso Valparaiso Chile Departamento de Matemdtica Universidad Tdcnica Federico Santa Maria Valparaiso Chile Departamento de Matemdticas Facultad de Ciencias Universidad Nacional Autonoma de Mdxico Ciudad de Mexico Mexico

This work deals with a three-dimensional system, which describes a food web model consisting of a prey, a specialist predator and a top predator which is generalist as it consumes the other two species. Using tools of dynamical systems we prove that the trajectories of system are bounded and that open subsets of parameters exist, such that the system in the first octant has at most two singularities. For an open subset of the parameters space, the system is shown to have an invariant compact set and this is a topologically transitive attractor set. Finally, we find another open set in the parameters space, such that the system has two limit cycles each contained in different invariant planes. The work is completed with a numeric simulation showing the attractor is a strange attractor.

关键词： Food chain functional response bifurcation behavior dynamic separatrix curve stability.

On Building Practical Biocomputers for Real-world Applications： Receptacles for Culturing Slime Mould Memristors and Component Standardisation

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Journal of Bionic Engineering 2017年第1期14卷 151-162页

作者： Edward Braund eduardo Reck Miranda Interdisciplinary Centre for Computer Music Research (ICCMR) The House Plymouth University Drake Circus UK PL4 8AA

Our application of bionic engineering is novel： we are interested in developing hybrid hardware-wetware systems for music. This paper introduces receptacles for culturing Physarum polycephalum-based memristors that are highly accessible to the creative practitioner. The myxomycete Physarum polycephalum is an amorphous unicellular organism that has been found to exhibit memristive properties. Such a discovery has potential to allow us to move towards engineering electrical systems that encompass Physarum polycephalum components. To realise this potential, it is necessary to address some of the constraints associated with harnessing living biological entities in systems for real-time application. Within the paper, we present 3D printed receptacles designed to standardise both the production of components and memristive observations. Subsequent testing showed a significant decrease in growth time, increased lifespan, and superior similarity in component-to-component responses. The results indicate that our receptacle design may provide means of implementing hybrid electrical systems for music technology.

关键词： unconventional computing Physarum polycephalum computer music biological computing memristor

Corrigendum to“Grain-size and compositional variability of Yarlung Tsangpo sand(Xigaze transect,south Tibet):Implications for sediment mixing by fluvial and aeolian processes”[Journal of Palaeogeography 12(2)(2023)195-210]

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Journal of Palaeogeography 2024年第2期13卷 374-374页

作者： Wen Lai Wen-Dong Liang Xiu-Mian Hu eduardo Garzanti Hua-Yu Lu Xiao-Long Dong Frontiers Science Center for Critical Earth Material Cycling School of Geography and Ocean Science Nanjing University Nanjing 210023 Jiangsu Province China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Institute of Sedimentary Geology Chengdu University of Technology Chengdu 610059 Sichuan Province China State Key Laboratory of Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University Nanjing 210023 Jiangsu Province China Department of Earth and Environmental Sciences Universita di Milano-Bicocca Milano 20126 Italy

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