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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

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Freeze-thaw cycles and associated geomorphology in a post-glacial environment:current glacial,paraglacial,periglacial and proglacial scenarios at Pico de Orizaba volcano,mexico

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Journal of mountain Science 2024年第6期21卷 1954-1977页

作者： víctor SOTO Carlos m.WELSH R. Kenji YOSHIKAWA Hugo DELGADO GRANADOS Centro de Ciencias de la Tierra Universidad VeracruzanaCircuito Gonzalo Aguirre BeltránS/NZona Universitaria91090XalapaMéxico Water and Environmental Research Center University of Alaska FairbanksFairbanksAlaska 99775USA Instituto de Geofísica Universidad Nacional Autónoma de MéxicoCiudad de México 04150México Department of Earth and Environmental Sciences Ludwig Maximilians UniversitätMunich 80333Germany

The glacial history of Pico de Orizaba indicates that during the Last Glacial maximum,its icecap covered up to~3000 m asl;due to the air temperature increasing,its main glacier has retreated to 5050 m *** retraction of the glacier has left behind an intense climatic instability that causes a high frequency of freeze-thaw cycles of great intensity;the resulting geomorphological processes are represented by the fragmentation of the bedrock that occupies the upper parts of the *** is a notable lack of studies regarding the fragmentation and erosion occurring in tropical high mountains,and the associated geomorphological risks;for this reason,as a first stage of future continuous research,this study analyzes the freezing and thawing cycles that occur above 4000 m asl,through continuous monitoring of surface ground *** results allow us to identify and characterize four zones:glacial,paraglacial,periglacial and *** was found that the paraglacial zone presents an intense drop of temperature,of up to~9℃ in only sixty *** rock fatigue and intense freeze-thaw cycles that occur in this area are responsible for the high rate of rock disintegration and represent the main factor of the constant slope dynamics that occur at the *** activity decreases,both in frequency and intensity,according to the distance to the glacier,which is where the temperature presents a certain degree of stability,until reaching the proglacial zone,where cycles are almost non-existent,and therefore there is no gelifraction *** geomorphological processes have resulted in significant alterations to the mountain slopes,which can have severe consequences in terms of risk and water.

关键词： Freeze-Thaw Gelifraction mountain mechanical erosion Periglacial geomorphology Postglacial scenarios

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Geochemistry and mineralogy of beach sediments in the northern Gulf of mexico,Tamaulipas state,mexico:implication for provenance

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Journal of Palaeogeography 2024年第3期13卷 375-400页

作者： mayank Shukla Sanjeet K.verma mayla A.Ramos-vázquez John S.Armstrong-Altrin Karla R.Hernández-martínez Sumit mishra vivek P.malviya Héctor Hernández-mendoza Posgrado de la Division de Geociencias Aplicadas Instituto Potosino de Investigacion Científica y Tecnologica(IPICYT)Camino a la Presa San José2055San Luis Potosí78216Mexico Division de Geociencias Aplicadas Instituto Potosino de Investigación Científica y Tecnologica(IPICYT)Camino a la Presa San Jose 2055San Luis Potosí78216Mexico Universidad Nacional Autonoma de méxico Instituto de Ciencias del Mar y LimnologíaUnidad de ProcesosOceanicos y CosterosCiudad UniversitariaCiudad de México 04510Mexico Department of marine Sciences Bharathidasan UniversityTiruchirappalli620024Tamil NaduIndia Instituto de Geociencias Universidad Nacional Autonoma de MéxicoBoulevard Juriquilla 300176230JuriquillaQueretaroMexico Department of Applied Geology Dr.Harisingh Gour Central UniversitySagar470002Madhya PradeshIndia Instituto de Investigacion de Zonas Desérticas Universidad Autònoma de San Luis PotosíAltair 200CP 78377San LuisS.L.P.Mexico Universidad del Centro de mexico Capitán Caldera 75CP 78250San LuisS.L.P.Mexico

Geochemical and mineralogical studies were performed in the La Pesca(LP)and Tesoro Altamira(TA)beach sediments,located in the Tamaulipas state,northern Gulf of *** main aim of this study is to infer the weathering history and provenance and to discriminate the tectonic environment of the beach *** sediments are composed of quartz with small amounts of accessory minerals such as plagioclase,calcite,orthoclase,microcline,and *** beach sediments are classified as fine-grained and very well sorted,however LP has coarse skewed and leptokurtic sediments,whereas TA has fine-skewed and very leptokurtic *** chemical index of weathering(CIW’)indicates intense weathering in the source *** quartz grain microtextures in the LP and TA are classified into mechanical,chemical,and mechanical/chemical *** features such as fractures,pits,percussion marks,abrasion fatigue,and v-shaped marks favor high-energy littoral,fluvial,subaqueous-marine,and aeolian *** chemical features indicate solution pits and crystalline overgrowth,which suggests a silica saturated marine *** mechanical/chemical features display adhering particles and elongated depressions suggest formation in a sub-aqueous nearshore marine *** and trace elements-based provenance discrimination diagrams indicate a felsic source derived from the mesa Central(mC),Sierra madre Oriental(SmOr)and Oaxaquia *** major and trace element concentrations imply a passive margin setting for the northern Gulf of mexico,which is consistent with the general geology.

关键词： Beach sediments Geochemistry mineralogy Provenance Tamaulipas Tectonic setting

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Processes involving soil CO_(2)dynamic in a sector of Chaco-Pampean plain,Argentina:An isotope geochemical approach

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Acta Geochimica 2024年第5期43卷 947-958页

作者： Sanci Romina Panarello Héctor Instituto de Geociencias Básicas Aplicadas y Ambientales de Buenos Aires(IGEBA)Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresCABAIntendente Güiraldes 2160Pabellón IIPiso 1C1428EGA Ciudad UniversitariaArgentina Instituto de Geocronología y Geología Isotópica(INGEIS) Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresCABAIntendente Güiraldes 2160Pabellón INGEISC1428EGA Ciudad UniversitariaArgentina

The magnitude and spatial variability of CO_(2)surface emissions and processes involving CO_(2)released to the atmosphere from the soils are relevant issues in the context of climate *** work evaluated CO_(2)fluxes and^(13)C/^(12)C ratio of vegetation,organic matter,and soil gases from no disturbed soils of Chaco Pampean Plain(Argentina)with different soil properties and environmental conditions(PL and PA units).Soil organic decomposition from individual layers was accompanied byδ^(13)C of total organic carbon(δ^(13)C-TOC)values more enriched to depth.δ^(13)C-TOC values in the upper soil profile~ca.0–15 cm were like the plant community of this area(~−33 to−29‰)whileδ^(13)CTOC varied stronger bellow horizon A,till~−24‰.Bothδ^(13)C-TOC and soilδ^(13)C-CO_(2)were similar(~−24 to 26‰)at deeper horizons(~50–60 cm).Toward the superficial layers,δ^(13)C-TOC andδ^(13)C-CO_(2)showed more differences(till~4‰),due influence of the diffusion *** A layer(~0–20 cm)from both PL and PA units contained the most enrichedδ^(13)C-CO_(2)values(~−15–17‰)because atmospheric CO_(2)permeated the soil air.A simple two-component mixing model between sources(atmosphericδ^(13)C-CO_(2)and soil CO_(2))confirmed that ***,CO_(2)fluxes reflected the biodegradation of C3 plants(source),diffusive transport,and CO_(2)exchange(atmosphere/soil).Soil moisture content appeared as a determining factor in the diffusion process and the magnitude of CO_(2)surface emissions(12–60 g·m^(−2)·d^(−1)).That condition was confirmed by CO_(2)diffusion coefficients estimated by air-filled porosity parameters and soil radon gradient model.

关键词： Soil CO_(2) Carbon isotopes Isotope fractionation Radon gases

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Cold and Fertile: Cryopreservation as an Innovative Tool in Addressing Challenges in Teratozoospermia

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Journal of Biosciences and medicines 2024年第2期12卷 274-281页

作者： víctor manuel Soto-márquez Jorge mulia-Rodríguez Daniel Osorio-González molecular Biophysics Laboratory Faculty of Sciences Autonomous University of State of Mexico Toluca Mexico

Teratozoospermia is an infertility issue that affects a significant number of couples of reproductive age. One of the potential causes contributing to the global decline in seminal quality includes factors such as diet, alcohol and tobacco consumption, high levels of stress, and environmental influences. This underscores the need to preserve the fertility of these patients through cryopreservation techniques. In this review, we explore the latest methods for freezing seminal samples, highlighting their advancements and advantages in addressing the challenge of perpetuating animal species, particularly in the context of human infertility.

关键词： Cryopreservation Teratozoospermia Infertility

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Realizing High Thermoelectric Performance in n-Type Se-Free Bi2Te3 materials by Spontaneous Incorporation of FeTe2 Nanoinclusions

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Energy & Environmental materials 2024年第4期7卷 344-354页

作者： Jamil Ur Rahman Woo Hyun Nam Yong-Jae Jung Jong Ho Won Jong-min Oh Nguyen van Du Gul Rahman víctor m.García-Suárez Ran He Kornelius Nielsch Jung Young Cho Won-Seon Seo Jong Wook Roh Sang-il Kim Soonil Lee Kyu Hyoung Lee Hyun Sik Kim Weon Ho Shin Leibniz Institute for Solid State and materials Research Advanced materials Convergence R&D Division Korea Institute of Ceramic Engineering & Technology Department of Electronic materials Engineering Kwangwoon University Department of Energy Engineering Dankook University Faculty of Fundamental Science Phenikaa University Department of Physics Quaid-i-Azam University Departamento de Física Universidad de Oviedo Nanomaterials and Nanotechnology Research Center-CINN Department of materials Science and Engineering Yonsei University School of Nano & materials Science and Engineering Kyungpook National University Department of materials Science and Engineering University of Seoul School of materials Science and Engineering Changwon National University

Bi2Te3-based materials have drawn much attention from the thermoelectric community due to their excellent thermoelectric performance near room ***,the stability of existing n-type Bi2（Te,Se）3materials is still low due to the evaporation energy of Se (37.70 kJ mol-1) being much lower than that of Te (52.55 kJ mol-1).The evaporated Se from the material causes problems in interconnects of the module while degrading the efficiency.

关键词： Bi2Te3 energy harvesting FeTe2 nanoinclusion n-type materials thermoelectric

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Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs víctor Cilleros-mañé Laia Just-Borràs marta Balanyà-Segura Aleksandra Polishchuk Laura Nadal marta Tomàs Carolina Silvera-Simón manel m.Santafé maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

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Advanced Oxidation Wastewater Treatment of 3 LPS of an Avocado Sauce Company,at morelia,michoacan,mexico

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Journal of Environmental Science and Engineering(A) 2024年第5期13卷 151-155页

作者： Alfonso Espitia-Cabrera Francisco Javier Barrón-Santos JoséL.méndez-Antonio Héctor m.Alemán-vásquez Omar G.Color-vázquez Saneamiento y Planeación Ambiental Azcapotzalco CDMX 02200México Energy Department Metropolitan Autonomous University Azcapotzalco CampusCDMX 02200Mexico Environmental System Engineering Department Environmental Engineering AcademyNational School of Biological SciencesNational Polytechnic InstituteCiudad de MéxicoCDMX 07738México Planta Congeladora y Empacadora Nacional Morelia 58190MichoacánMéxico

This paper describes the wastewater treatment of 3 liters per second of capacity of discharges of capacity,from the avocado washed,as well as the production of avocado *** were pretreated with a grease and oil trap and contained small amounts of oil and grease,dissolved and total solids,organic matter and trace of organic and inorganic compounds from the vitamins and minerals of *** treatment train is located in an small surface and the train is integrated with coagulation in line with alumina in a static mixer,rapid filtration in two steps,double advanced oxidation with ozone and heterocyclic photocatalysis with a nanofilm of zinc oxide as,photocatalyzer and final adsorption of refractory compounds with activated *** treated wastewater meets the environmental regulation to urban sewerage discharges of the city,according to the results of a mexican Certified Laboratory.

关键词： Wastewater primary treatment rapid filter performance static mixer

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Organ Abscission in Plants: With Special Emphasis on Bell Pepper

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1467-1484页

作者： Ramiro Reyes-Castro Héctor G.Núñez-Palenius Juan I.valiente-Banuet maría E.Sosa-morales Blanca E.Orosco-Alcalá Rafael Guzmán-mendoza Graciela m.L.Ruiz-Aguilar Rogelio Costilla-Salazar Life Sciences Division Universidad de GuanajuatoIrapuato36500México School of Engineering and Sciences Tecnologico de MonterreyQuerétaro76130México

Bell pepper(Capsicum annuum L.),along with potato and tomato,is one of the three most cultivated vegetables in the *** pepper is worldwide accepted due to its characteristics of color,smell,ﬂavor,and *** pepper is also considered a nutritious food due to its vitamin and antioxidant *** mexico,bell pepper production has a high value because it is grown for the international markets,particularly the United States of ***,the abscission ofﬂowers and fruits is a factor that limits the yield,hinders the planning of activities,and causes a variation in the prices of *** to the importance of this process,in this work we did a bibliometric analysis and literature review of scientiﬁc advances for the understanding of the abscission pro-cess in plants,and in particular for the bell ***,we introduce new perspectives that would help direct future research about organ abscission in ***,the lack of research that would further clarify abscis-sion process in the bell pepper plant is discussed.

关键词： Capsicum annuum abscission zone plant growth regulators environmental factors

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The potential of starch-chitosan blends with poloxamer for the preparation of microparticles by spray-drying

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Particuology 2024年第6期89卷 1-10页

作者： Juan Enrique Barranco-García Carolina Caicedo Enrique Javier Jiménez-Regalado Carlos Espinoza-González Graciela morales Rocio Yaneli Aguirre-Loredo Abril Fonseca-García Tecnológico Nacional de méxico/Instituto Tecnológico de Oaxaca Departamento de Química y BioquímicaAvenida Ing.Víctor Bravo Ahuja No.125Esquina Calzada Tecnológico68030OaxacaMexico Faculty of Engineering Unidad Central del Valle del Cauca(UCEVA)Carrera 17a 48-144763022TuluáColombia Centro de Investigación en Química Aplicada(CIQA) Blvd.Enrique Reyna Hermosillo 14025294SaltilloCoahuilaMexico Investigadoras por méxico CONAHCYT-CIQA Av.Insurgentes Sur 1562Col.Crédito Constructor03940Alcaldía Benito JuárezCDMXMexico

Using biopolymers as wall materials in spray drying poses challenges,particularly in attaining flowability and thermal stability among their physicochemical *** paper addresses these challenges by preparing microparticles using a blend of starch–chitosan and a poloxamer,commercially named Pluronic®*** aimed to elucidate the effects of varying poloxamer concentrations on the resulting particles through the spray drying *** with a poloxamer concentration of 3%(w/v)demonstrated a notably higher yield,especially when compared to those with 0%and 1%*** with 3%and 5%(w/v)poloxamer displayed a narrower particle size distribution,with the 3%blend showing a superior yield attributed to arrangements of blend components that improve flowability.X-ray diffraction analysis showcased the characteristic peaks of A-type starch form,with shifts suggesting enhanced interactions between *** with increased poloxamer content showed elevated thermal degradation temperatures,with the 3%blend registering a significant rise,opening avenues for encapsulating heat-sensitive *** study primarily focuses on the preparation and basic characterization of *** underscores the potential of blends with optimal poloxamer concentrations in microencapsulation,emphasizing further research to harness their capabilities thoroughly.

关键词： Biopolymer Starch Chitosan Pluronic®F127 microparticles Spray drying

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