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Hydrogeochemical and isotopic assessment of the origin of nO_(3)^(−)and n-nH_(3)contents in the aquifer located in a closed lacustrine volcano-sedimentary basin in the metropolitan area of Mexico City

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Acta geochimica 2024年第4期43卷 719-736页

作者： Jose ivan Morales-Arredondo Maria Aurora Armienta Hernandez joel Edmundo Ortega-gutierrez Elisa Cuellar Ramirez natural Resources Department Institute of GeophysicsNational Autonomous University of MexicoCiudad Universitaria No.3000Col.Copilco UniversidadCoyoacán Delegation04360 MexicoCDMXMexico Instituto Politecnico nacional ***án 55La Laguna Ticoman07340 MexicoCDMXMexico Benemérita Universidad Autónoma de Puebla Ciudad Universitaria Col.San ManuelPueblaPueMexico

To explain the presence and spatial distribution of nO_(3)^(−)and n-nH_(3)in the Aquifer of the Metropolitan Area of Mexico City(AMAMC),a hydrogeochemical and isotopic analysis using^(13)C DIC(as well as the stable isotopes^(18)O and^(2)H)in groundwater was *** aquifer is located in an old closed lacustrine volcano-sedimentary basin;some wells hosted in the semi-confined zone contain high n-nH_(3)concentrations,while others present nO_(3)^(−)contents in the recharge zones(hosted in an oxidizing environment).In this study,a change in the isotopic signature(primarily in^(18)O and^(2)H)was observed from the recharge zones to the basin center in some of the wells with high nO_(3)^(−)concentrations,this behavior can be attributed to evaporation during the incorporation of recently infiltrated *** addition,the results for^(13)C(along with ^(2) H)in wells with the highest n-nH_(3)concentrations exhibited an atypically broad range of *** indicated the occurrence of hydrogeochemical and/or biochemical processes in the aquifer(in an oxidizing or reducing environment),such as organic degradation,bacterial decomposition(primarily in the ancient Lake Texcoco and which acts as a natural sink for carbon,nitrogen,sulfur,and phosphorus),besides rock weathering and dissolution,which may be responsible for a very marked isotopic modification of the^(13)C(and,to a lesser extent,2 H).Methanotrophic bacterial activity and methanogenic activity may be related to n-nH_(3)removal processes by oxidation and residual water incorporation respectively,whereas the increase in the nO_(3)^(−)content in some wells is due to the recent contribution of poor-quality water due to contamination.

关键词： 18 O and^(13)C isotopes Iron Hydrogeochemical processes nitrate nitrogen species

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Shade shelters increase survival and photosynthetic performance of oak transplants at abandoned fields in semi-arid climates

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Journal of Forestry Research 2013年第1期24卷 23-28页

作者： Claudia g.nzález-Salvatierra Ernesto iván Badano joel Flores Juan Pablo Rodas División de Ciencias Ambientales Instituto Potosino de Investigación Científica y TecnológicaA.C.Camino a la Presa San José 2055C.P. 78216San Luis PotosíS.L.P.México.

Forest restorations conducted in semiarid, seasonally dry climates must deal with the intense drought stress that affects tree seedlings during the dry season. Although this water deficit is the most commonly invoked source of mortality for seedlings, several other environmental factors may also preclude survival of transplants. For instance, it has been widely reported that excessive light reduces the efficiency of the photosynthetic apparatus, hence decreasing plant survival, but most seedling transplants in deforested areas are conducted under these light conditions. This study is focused in determining whether excessive light affects the photosynthetic performance and survival of Quercus coccolobifolia, a Mexican oak species, when their seedlings are transplanted in semiarid deforested areas. Further, this study tests the possibility of using artificial shade shelters to improve the ecophysiological performance and survival of seedlings. Oak seedlings were transplanted under full sunlight conditions and beneath artificial shade shelters of two different colors： white and black. To reduce water stress, and hence isolate the effects of light treatments, a drip irrigation system was implemented at each experimental plot. Seedling survival was monitored weekly for 128 days and photosynthetic performance was assessed by measuring chlorophyll fluorescence at three opportunities during the experiment. Sun-exposed seedlings showed lower photosynthetic performance and survival rates than those beneath shelters of both colors. These results suggest that sunlight damage can reduce seedling survival when they are transplanted in exposed sites, and that shade shelters can improve the success of forest restoration programs in semiarid climates.

关键词： chlorophyll fluorescence light stress photoinhibition reforestation forest restoration

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Pancreatic Pseudocyst Rupture: Cause of Acute Abdomen

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Case Reports in Clinical Medicine 2023年第8期12卷 324-331页

作者： joel iván cruz-g.nzález Miguel Ángel Miranda-Del Olmo Benito Antonio garcía-Ramón Brenda Hernández-garcía Crystell guadalupe guzmán-Priego Alejandro Jiménez-Sastré Social Security Institute of the State of Tabasco Villahermosa Mexico Cardiometabolism Laboratory Academic Division of Health Sciences Juarez Autonomous University of Tabasco Villahermosa Mexico

Case report of a 23-year-old male patient with a pancreatic pseudocyst, initially was treated by the Interventional Radiology service by placing percutaneous drainage with poor evolution, abruptly presented abdominal pain, Systemic Inflammatory Response Syndrome and peritoneal irritation, so an urgent exploratory laparotomy was performed with a finding of rupture of the pancreatic pseudocyst into the abdominal cavity. He presented septic shock and died in the immediate postoperative period. Computerized Axial Tomography represents the ideal diagnostic method. Spontaneous rupture is extremely rare and requires urgent surgical intervention.

关键词： Rupture Pancreatic Pseudocyst Acute Abdomen

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Pancreatic Pseudocyst Rupture: Cause of Acute Abdomen

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Case Reports in Clinical Medicine（临床医学病理报告） 2023年第8期

作者： joel iván cruz-g.nzález Miguel Ángel Miranda-Del Olmo Benito Antonio garcía-Ramón Brenda Hernández-garcía Crystell guadalupe guzmán-Priego Alejandro Jiménez-Sastré

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Flow Routing in the natural Channel of the Ichu River Experimental Basin through Artificial neural networks

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Journal of Environmental Science and Engineering(A) 2018年第10期7卷 387-403页

作者： iván Ayala Bizarro joel Oré Iwanaga David Requena Machuca Richard Oré Cayetano Edwin Torres Condori Edwin Montes Raymundo Department of Civil Engineering National University of HuancavelicaHuancavelica 09001Peru

The objective of the investigation is to carry out the flow routing in the natural channel of the experimental basin of the Ichu river, by means of the Artificial Intelligence technique of Anns (Artificial neural networks). generally, hydrological and hydraulic methods require different parameters of the river channel, while the Anns method simplifies the amount of data. The study area is located in the experimental basin of the Ichu river, upstream of the city of Huancavelica in an area of 607 km^2. A calibrated and validated model of the rain-runoff process was developed, with data recorded in 6 automatic meteorological stations (rainfall) and one hydrological station (runoff). The model HEC-1 was used to model the rain-runoff process and the Muskingun-Cunge method for the flood rounting, generating historical records for 5 stretches of the Ichu riverbed and obtaining 39 maximum historical records in the 2016 periods and 2017. The model obtained values of nash-Sutcliffe efficiency coefficients (E) equal to 0.851 and 0.828 for the calibration and validation stage, respectively. The Anns were built with different architectures to train and obtain the architecture that best fits the historical phenomena. Finally, the architecture 1-5-1 presented a better fit, whose statistical E was values of 0.881 and 0.859 in the training and validation stage respectively.

关键词： Rain-runoff process flood routing Anns

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growth of Circulating Tumor Cell-Derived Colonies from Peripheral Blood of Melanoma Patients: Preliminary Characterization of Colony Composition

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Health 2014年第12期6卷 1467-1481页

作者： Wolfram E. Samlowski John R. Mcgregor Suzanne T. Samlowski Shweta Tharkar Shirley Shen joel S. Bentz Department of Oncology Comprehensive Cancer Centers of Nevada Las Vegas USA genomics Core Facility University of Nevada Las Vegas Las Vegas USA LMC Pathology Las Vegas USA TrueCells LLC Las Vegas USA

Circulating tumor cells (CTC) are rarely detected in the blood of cancer patients, even though they are a direct harbinger of eventual patient demise. We developed an innovative CTC culture technology to allow more sensitive isolation, expansion, and characterization of viable colonies from patient blood. In this assay, the entire leukocyte fraction from 10 ml of anticoagulated patient blood is placed into culture medium without any pre-selection. After 16 days in culture, CTC derived colonies are counted. As a proof-of-principle, blood samples from 58 Stage IIa-iv melanoma patients were tested. ninety percent of these samples grew colonies. The colony numbers ranged from 0 - 308 (mean 63 ± 9.5 SEM). Ten normal volunteers had virtually no growth (mean 0.5 ± 1.4 colonies). Colonies were harvested using a micropipette for characterization. Tumor-cell containing spheroids were embedded in paraffin, sectioned, and stained with melanoma-specific mAb for histologic characterization. MITF proved to be the most consistent immunostain that identified melanoma cells in these colonies. A host-cell component in colonies was also identified using CD68 and CD43 mAb staining. Following enzymatic dissociation of colonies, a variety of immunostains were tested. Papanicolau staining proved most useful for identifying the abnormal nuclei of tumor cells. Flow cytometry could readily distinguish host and tumor cell populations based on DnA content and forward/side scatter in dissociated colonies. The stem cell marker ALDH1A1 associated with the aneuploid population, but CD45 was expressed on both diploid and aneuploid cells. The ability to repeatedly isolate CTC derived colonies from cancer patient blood samples opens the door to a novel type of long-term clinical monitoring. This novel CTC culture technology may prove useful to perform molecular characterization, assessment of treatment response, and testing of drug sensitivity and resistance in patients during treatment.

关键词： Circulating Tumor Cells CTC Colonies CTC Cultures Melanoma Flow Cytometry CTC Derived Colonies

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Therapeutic Routes of a group of Heart Failure Patients Followed in a Cameroonian Urban Setting

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World Journal of Cardiovascular Diseases 2023年第10期13卷 686-700页

作者： Chris nadège nganou-gnindjio Bâ Hamadou Melissa Djuidje Djampouop Marie ntep gwet Félicité Kamdem Pierre Mintom Juliette Valerie ndobo Siddikatou Djibrilla guillaume Ebene Manon joel noutackdie Tochie Samuel Kingue Faculty of Medicine and Biomedical Sciences University of Yaoundé 1 Yaoundé Cameroon Institut Supérieur des Sciences de la Santé Université des Montagnes Bangangte Cameroon Faculty of Medicine and Pharmaceuticals Sciences University of Douala Douala Cameroon Faculty of Health Sciences University of Buea Buea Cameroon

Background: Heart failure (HF) is a rising global health problem. Patients with HF tend to use several therapies obtained via different treatment routes to relieve their symptoms. It is rampant in sub-Saharan Africa (SSA), leading to poor health-seeking behaviours and worsened HF health outcomes. We aimed to describe the different therapeutic routes of HF patients from the onset of their first symptom until treatment in a specialised cardiology centre to identify and rebuke harmful therapeutic routes. Materials and Methods: This was a cross-sectional study at the Yaoundé Central Hospital in Cameroon between December 2018 to July 2019. Patients were recruited by consecutive convenient sampling. Adult patients aged above 18 years with confirmed HF were included using the Framingham criteria. Variables relating to socio-demographic and clinical data and the health-seeking behaviours of HF patients were studied. Results: We included 132 patients with a mean age of 62.90 years (62.88% women). Very few patients (0.90%) followed an ideal route;60.71% of subjects had a pseudo-ideal route, 19.64% accessed a specialised facility directly, and 21.42% used an erratic route. At the arrival time in a cardiology unit, 49.24% and 35.61% of our subjects were in nYHA stage III and iv HF compared to 15.15% for stage II. none of them was in Stage I. Conclusion: Most heart failure patients in Cameroon have resorted to non-specialised care, which worsens their clinical presentation. There is an urgent need for health education of HF patients in our context.

关键词： Heart Failure Therapeutic Care Route Cameroon

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