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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

Trichoderma *** Bacillus *** growth promoters in maize(Zea mays L.)

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Phyton-International Journal of Experimental Botany 2019年第1期88卷 37-46页

作者： López-Valenzuela BE Armenta-Bojórquez AD Hernández-Verdugo S Apodaca-Sánchez MA Samaniego-Gaxiola JA Valdez-Ortiz A Universidad Autónoma de Sinaloa.facultad de Agricultura del Valle del fuerte.Avenida Japaraqui y Calle 16 s/n Juan JoséRíosSinaloaC.P 81110México Universidad Autónoma de Baja California.Instituto de ciencias Agrícolas.Carretera a delta s/n Ejido Nuevo leónBaja CaliforniaC.P.21705México Instituto Politécnico Nacional.Centro Interdisciplinario de Investigación para el desarrollo Integral Regional Unidad Sinaloa.Blvd.Juan de Dios Bátiz Paredes#250 Colonia San JoachinGuasaveSinaloaC.P.81101México Universidad Autónoma de Sinaloa Facultad de Agronomía.Km.17.5Carretera Culiacán-El DoradoCuliacán RosalesSinaloaC.P.80000México Instituto Nacional de Investigaciones forestales Agrícolas y Pecuarias Campo Experimental La LagunaBlvd.JoséSantos Valdez 1200 Pte.MatamorosCoahuilaC.P.27440México Universidad Autónoma de Sinaloa Facultad de Ciencias Químico Biológicas.Calzada de las Américas y Calle Universitarioss/n.Ciudad UniversitariaCuliacánSinaloaC.P.80013México

Microbes that are beneficial to plants are used to enhance the crop growth,yield and are alternatives to chemical *** and Bacillus are the predominant plant growth-promoting fungi and *** objective of this study was select,characterize,and evaluate isolates of Trichoderma *** Bacillus *** from the northern region of Sinaloa,Mexico,and assess their effect on growth promotion in maize(Zea mays L.).In greenhouse conditions,four Trichoderma isolates and twenty Bacillus isolates,as well as two controls,were tested in a completely randomized design with three *** selected the two best strains of Trichoderma and Bacillus:TB=Trichoderma asperellum,Tf=Trichoderma virens,B14=Bacillus cereus sensu lato and B17=Bacillus cereus,which were evaluated in the field in a completely randomized blocks in factorial arrangement design with three replicates applying different rates of nitrogen fertilizer(0,150 kg N/ha,and 300 kg N/ha).Treatments 5(B17=***)and 11(Tf=***)both fertilized with 150 kg N/ha showed similar yields and they did not reveal significant differences from the treatments fertilized with 300 kg N/*** indicated that treatment 5(B17=*** with 150 kg N/ha)and treatment 11(Tf=*** with 150 kg N/ha)were efficient as growth promoters,by not showing significant differences in root volume and dry weight of *** results indicated a reduction of 50% in the rate of nitrogen to fertilizer required for maize(Zea mays L.)*** microorganisms Trichoderma and Bacillus could be an alternative to reduce the use of chemical fertilizers in maize.

关键词： Trichoderma Bacillus Native strains Biofertilizers

Optimization of Analytical Conditions to determine Steroids and Pharmaceuticals Drugs in Water Samples Using Solid Phase-Extraction and HPLC

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American Journal of Analytical Chemistry 2011年第8期2卷 863-870页

作者： Ramiro Vallejo-Rodriguez Alberto Lopez-Lopez Hugo Saldarriaga-Norena Mario Murillo-Tovar Leonel Hernandez-Mena Centro de Investigacion y Asistencia en Tecnologia y Diseno del Estado de Jalisco(CIATEJ) Normalistas 800Colinas de la NormalGuadalajaraMexico facultad de ciencias Quimicas Universidad Autonoma de CoahuilaRepublica Ote.SaltilloMexico

Two reliable methods were optimized to determine two steroids (17?-Estradiol and 17?-Ethinylestradiol) and two pharmaceutical drugs (ibuprofen and naproxen) using Solid-Phase Extraction (SPE) for sample preparation and High Performance Liquid Chromatography (HPLC) for analysis. SPE (C18) conditions were evaluated varying elution solvent volume, pH conditions and sample mass in the cartridge and reduction techniques of the extract. The efficiency of the analytical methods was evaluated by spiking ultrapure water samples with compounds at three and four levels of concentration for steroids and pharmaceutical drugs, re- spectively. The recoveries were independent (P > 0.05) of added mass of target analytes with a repeatability lower than 6.5% for steroids and 12.1% for pharmaceutical compounds. The recovery factor (coefficient of variation, CV) was higher than 83% for steroids (CV 93% for pharmaceuticals (CV for the evaluation of a steroid degradation test using ozone, finding that the estimated limit of detection is sufficient to determine the residual mass (μg?L–1) of 17β-Estradiol after the experiment.

关键词： Steroids Pharmaceuticals Drugs Solid-Phase Extraction HPLC-DAD

Changes in the Abundance and Composition of Phytoplankton in a Coastal Lagoon during Neap-Spring Tide Conditions

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Open Journal of Marine Science 2014年第2期4卷 80-100页

作者： María fernanda Gracia-Escobar Roberto Millán-Núnez Adriana González-Silvera Eduardo Santamaría-del-Angel Víctor f.Camacho-Ibar Charles C.Trees facultad de ciencias Marinas Universidad Autónoma de Baja CaliforniaEnsenadaMéxico Instituto de Investigaciones Oceanológicas Universidad Autónoma de Baja CaliforniaEnsenadaMéxico NATO Undersea Research Centre La SpeziaItaly

The objective of this work was to estimate the changes in abundance and composition of phytoplankton in a coastal lagoon in Baja California, México during neap-spring tide conditions. Sampling was conducted from the 7th to the 16th of October 2004. Surface water was collected at 18 stations distributed across the bay during day time at high tide. Also, a time series was collected at a fixed station;surface water was collected every two hours from 8:00 to 18:00. High temperatures, low salinities and low nutrient concentrations at the oceanic end indicated weak or non upwelling conditions during this period. The phytoplankton community was characterized using an inverted microscope and the chemical taxonomy program CHEMTAX, based on pigment concentration estimated by high performance liquid chromatography (HPLC). The phytoplankton concentration was two times lower during this period than during periods of upwelling in the same year. Cryptophytes and diatoms were the most abundant groups estimated by CHEMTAX. Statistical analyses of the effect of tidal conditions on phytoplankton composition indicate that Zone A is strongly affected by tides, and that tidal effects are lessened at the inner zones. Differences in phytoplankton abundance between zones and between tidal conditions indicate that phytoplankton distribution is patchy in the lagoon.

关键词： Phytoplankton HPLC Pigments CHEMTAX Tides Coastal Lagoon

Transcriptional cofactors Ski and SnoN are major regulatorsof the TGf-β/Smad signaling pathway in health and disease

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Signal Transduction and Targeted Therapy 2018年第1期3卷 184-198页

作者： Angeles C.Tecalco-Cruz Diana G.Rios-Lopez Genaro Vazquez-Victorio Reyna E.Rosales-Alvarez Marina Macias-Silva Instituto de Investigaciones Biomedicas at Universidad Nacional Autonoma de Mexico Mexico city 04510Mexico Instituto de fisiologia Celular at Universidad Nacional Autonoma de Mexico Mexico city 04510Mexico facultad de ciencias at Universidad Nacional Autonoma de Mexico Mexico city 04510Mexico

The transforming growth factor-β(TGf-β)family plays major pleiotropic roles by regulating many physiological processes in development and tissue *** TGf-βsignaling pathway outcome relies on the control of the spatial and temporal expression of>500 genes,which depend on the functions of the Smad protein along with those of diverse modulators of this signaling pathway,such as transcriptional factors and ***(Sloan-Kettering Institute)and SnoN(Ski novel)are Smadinteracting proteins that negatively regulate the TGf-βsignaling pathway by disrupting the formation of R-Smad/Smad4 complexes,as well as by inhibiting Smad association with the p300/CBP *** Ski and SnoN transcriptional cofactors recruit diverse corepressors and histone deacetylases to repress gene *** TGf-β/Smad pathway and coregulators Ski and SnoN clearly regulate each other through several positive and negative feedback ***,these cross-regulatory processes finely modify the TGf-βsignaling outcome as they control the magnitude and duration of the TGf-β*** a result,any alteration in these regulatory mechanisms may lead to disease ***,the design of targeted therapies to exert tight control of the levels of negative modulators of the TGf-βpathway,such as Ski and SnoN,is critical to restore cell homeostasis under the specific pathological conditions in which these cofactors are deregulated,such as fibrosis and cancer.

关键词： SnoN homeostasis Smad

Knowledge and preventive measures practiced by junior high school students from Mexico City regarding influenza A (H1N1)

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Health 2012年第10期4卷 995-999页

作者： Veronica Cruz-Licea fernando Gonzalez-Dominguez Laura Vargas-Parada Monica Hernandez-Riquelme Ana flisser departamento de Salud Publica Facultad de MedicinaUniversidad Nacional Autonoma de MexicoMexico CityMexico Direccion de Ensenanza Hospital General“Dr.Manuel Gea Gonzalez”Secretaria de SaludMexico CityMexico departamento de Biologia Facultad de CienciasUniversidad Nacional Autonoma de MexicoMexico CityMexico Direccion General de Innovacion y fortalecimiento Academico Administracion Federal de Servicios Educativos en el Distrito FederalSecretaria de Educacion PublicaMexico CityMexico departamento de Microbiologia y Parasitologia Facultad de MedicinaUniversidad Nacional Autónoma de MexicoMexico CityMexico

Background: Influenza A (H1N1) is the most recent pandemic disease that has affected the human population. Objective: To evaluate knowledge and preventive measures related with this disease one year after the epidemic of Mexico- that took place in 2009. Material and methods: An epidemiologic survey regarding influenza A (H1N1) was conducted in June 2010 among 2541 students from the second grade of all public high schools in a borough in Mexico City. The questionnaire included items on the knowledge of the disease and practice of preventive measures. Results: Most students obtained the information from television, half of them from parents and only one fifth from teachers;72% of the participants had a favorable knowledge about the disease and the measures to avoid being infected. However, only 37% practiced such preventive measures. Conclusion: Knowledge has a positive influence on practices towards health. Parents and teachers have an important role in health education, thus efforts should be directed to involve them more intensely in health education.

关键词： Alcohol Gel Epidemiologic Survey Hand Washing Health Behavior Influenza A (H1N1) Outbreak Mexico City

Lima Bean(Phaseolus lunatus)Protein Hydrolysates with ACE-I Inhibitory Activity

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food and Nutrition Sciences 2012年第4期3卷 511-521页

作者： Luis Chel-Guerrero Mario Domínguez-Magana Alma Martínez-Ayala Gloria Dávila-Ortiz David Betancur-Ancona facultad de Ingeniería Química Universidad Autónoma de YucatánMéridaMéxico Escuela Nacional de ciencias Biológicas Instituto Politécnico NacionalMiguel HidalgoMéxico Centro de Investigación en Biotecnología Aplicada Instituto Politécnico NacionalTlaxcalaMéxico

Several protein sources can be used to produce bioactive peptides with angiotensin I-converting enzyme (ACE) inhibittory activity. Protein concentrates from ungerminated and germinated lima bean Phaseolus lunatus seed flours were hydrolyzed with Alcalase 2.4 L or pepsin-pancreatin sequential hydrolysis, and ACE inhibitory activity measured in the different hydrolysis treatments. Protein hydrolysate production was analyzed with a 23 factorial design with four replicates of the central treatment. Evaluated factors were protein concentrate source (ungerminated seeds, PC1;germinated seeds, PC2), enzyme/substrate ratio E/S (1/50 or 1/10) and hydrolysis time (0.5 or 2.0 h for Alcalase;1 or 3 h for pepsin-pancreatin). degree of hydrolysis (DH) was high for the Alcalase hydrolysates (24.12% 58.94%), but the pepsin-pancreatin hydrolysates exhibited the highest ACE inhibitory activity (IC50 = 0.250 0.692 mg/mL). Under the tested conditions, the hydrolysates with the highest ACE inhibitory activity were produced with sequential pepsin-pancreatin using either PC1 at 1 h hydrolysis time and a 1/10 E/S ratio or PC2 at 1 h hydrolysis time and a 1/50 E/S ratio. Lima bean protein hydrolysates prepared with Alcalase or pepsin-pancreatin are a potential ingredient in the production of physiologically functional foods with antihypertensive activity.

关键词： Lima Bean degree of Hydrolysis ACE Inhibition Protein Hydrolysates IC50

Water treatment and reclamation by implementing electrochemical systems with constructed wetlands

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Environmental Science and Ecotechnology 2023年第4期16卷 88-105页

作者： Suanny Mosquera-Romero Eleftheria Ntagia Diederik P.L.Rousseau Abraham Esteve-Nú~nez Antonin Prevoteau Center for Microbial Ecology and Technology(CMET) Ghent UniversityCoupure Links 653B-9000GhentBelgium ESPOL Polytechnic University Escuela Superior Politécnica del LitoralESPOLFacultad de Ciencias Naturales y MatemáticasBOX9050Ecuador department of Green Chemistry and Technology Ghent UniversitySint-Martens-Latemlaan 2BB-8500KortrijkBelgium Centre for Advanced Process Technology for Urban Resource Recovery(CAPTURE) Frieda Saeysstraat 19000GhentBelgium UniversitéParis-Saclay INRAEPROSE92160AntonyFrance Universidad de Alcalá Department of Analytical ChemistryPhysical Chemistry and Chemical EngineeringAlcaláde HenaresSpain

Seasonal or permanent water scarcity in off-grid communities can be alleviated by recycling water in decentralized wastewater treatment ***-based solutions,such as constructed wetlands(CWs),have become popular solutions for sanitation in remote *** typical CWs can efficiently remove solids and organics to meet water reuse standards,polishing remains necessary for other parameters,such as pathogens,nutrients,and recalcitrant *** CW designs and CWs coupled with electrochemical technologies have been proposed to improve treatment *** systems(ECs)have been either implemented within the CW bed(ECin-CW)or as a stage in a sequential treatment(CW+EC).A large body of literature has focused on ECin-CW,and multiple scaled-up systems have recently been successfully implemented,primarily to remove recalcitrant ***,only a few reports have explored the opportunity to polish CW effluents in a downstream electrochemical module for the electro-oxidation of micropollutants or electro-disinfection of pathogens to meet more stringent water reuse *** paper aims to critically review the opportunities,challenges,and future research directions of the different couplings of CW with EC as a decentralized technology for water treatment and recovery.

关键词： Sanitation and reuse Disinfection Advanced oxidation decentralized systems Electrification

Evaluation of Three Dynamic Models for Aerated facultative Lagoons

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Journal of Water Resource and Protection 2015年第14期7卷 1131-1142页

作者： Carlos Joel Abrego-Gongora Roberto Briones-Gallardo Luis Armando Bernal-Jacome Antoni Escalas-Canellas Programa Multidisciplinario de Posgrado en ciencias Ambientales Universidad Autonoma de San Luis PotosiSan Luis PotosiMexico Instituto de Metalurgia-facultad de Ingenieria Universidad Autonoma de San Luis PotosiSan Luis PotosiMexico Centro de Investigacion y Estudios de Posgrado Facultad de IngenieriaUniversidad Autonoma de San Luis PotosiSan Luis PotosiMexico department of Chemical Engineering&Terrassa School of Engineering Universitat Politecnica de CatalunyaTerrassaSpain Laboratory of Control of Environmental Contamination Institute of Textile Research and Industrial Cooperation of Terrassa(INTEXTER)Universitat Politecnica de CatalunyaTerrassaSpain

In this research, three existing dynamic mathematical models for aerated lagoons were applied to an aerated facultative lagoon (AfL) plant for municipal wastewater treatment. The models’ ability to describe the behavior of the primary lagoon was evaluated, and the advantages and limitations of the three models were compared. for this purpose, 7-year operational data from the municipal WWTP were collected and processed;other necessary data—like dynamic temperature values— were estimated. A 2-year period was used for model calibration, while the remaining 5 years served as validation period. One of the models showed poor calibration fit values in the effluent concentration description (R2 of 0.242 and RMSE of 16.8 mg/L);however, with some modifications the adjust was enhanced (R2 of 0.409 and RMSE of 14.0 mg/L);a second model displayed a poor to moderate adjust (0.489 and 13.0 mg/L, respectively), and the third model achieved a moderate fit (0.528 and 11.9 mg/L), though it provided an overestimation of effluent concentration, especially in periods of heavy and frequent rain;this model with some adaptations the adjust was enhanced (R2 of 0.575 and RMSE of 11.4 mg/L). The validation fits are even lower, illustrating the inability of these models to properly describe the AfL behavior. The possible causes of the models’ inadequacy are discussed. finally, it is established that in terms of AfL behavior description more research and model development are needed.

关键词： Aerated facultative Lagoons Oxygen demand Mathematical Modeling