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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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Association of Congenital Heart Defects (CHD) with Factors Related to Maternal Health and Pregnancy in Newborns in Puerto Rico

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Congenital Heart Disease 2024年第1期19卷 19-31页

作者： Yamixa Delgado Caliani Gaytan Naydi Perez Eric Miranda Bryan Colón morales Mónica Santos Biochemistry&Pharmacology Department San Juan Bautista School of MedicineCaguas00726Puerto Rico Hispanic Alliance for Clinical and Translational Research University of Puerto Rico Medical Sciences CampusSan Juan00936Puerto Rico Department of Internal Medicine University of Puerto Rico Medical Sciences CampusSan Juan00936Puerto Rico

Background:Given the pervasive issues of obesity and diabetes both in Puerto Rico and the broader United States,there is a compelling need to investigate the intricate interplay among body mass index(BMI),pregesta-tional,and gestational maternal diabetes,and their potential impact on the occurrence of congenital heart defects(CHD)during neonatal ***:Using the comprehensive System of Vigilance and Surveillance of Congenital Defects in Puerto Rico,we conducted a focused analysis on neonates diagnosed with CHD between 2016 and *** assessment encompassed a range of variables,including maternal age,gestational age,BMI,pregestational diabetes,gestational diabetes,hypertension,history of abortion,and presence of ***:A cohort of 673 patients was included in our *** average maternal age was 26 years,within a range of 22 to 32 *** mean gestational age measured 39 weeks,with a median span of 38 to 39 *** the 673 patients,274(41%)mothers gave birth to neonates diagnosed with *** this group,22 cases were linked to pre-gestational diabetes,while 202 were not;20 instances were associated with gestational diabetes,compared to 200 without;and 148 cases exhibited an overweight or obese BMI,whereas 126 displayed a normal ***:We identiﬁed a statistically signiﬁcant correlation between pre-gestational diabetes mellitus and the occurrence of ***,our analysis did not show a statistically signiﬁcant association between maternal BMI and the likelihood of *** results may aid in developing effective strategies to prevent and manage CHD in neonates.

关键词： Congenital heart defects(CHD) obesisty maternal health diabetes body mass index(BMI)

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Effects of metoclopramide on gastric motility measured by short-term bio-impedance

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World Journal of Gastroenterology 2009年第38期15卷 4763-4769页

作者： María-Raquel Huerta-Franco Miguel Vargas-Luna Kathleen M Capaccione Etna Yaez-Roldán Ulises Hernández-Ledezma Ismael morales-Mata Teodoro Córdova-Fraga Department of Applied Science and Labor Research DCS-Campus LeónUniversity of Guanajuato Department of Physical Engineering DCI-Campus LeónUniversity of Guanajuato Robert Wood Johnson Medical School The University of Medicine and Dentistry of New Jersey

AIM:To analyze the accuracy of short-term bio-impedance as a means of measuring gastric ***: We evaluated differences in the short-term electrical bio-impedance signal from the gastric region in the following conditions: (1) fasting state, (2) after the administration of metoclopramide (a drug that induces an increase in gastric motility) and (3) after food ingestion in 23 healthy volunteers. We record-ed the real component of the electrical impedance signal from the gastric region for 1000 s. We performed a Fast Fourier Transform (FFT) on this data and then compared the signal among the fasting, medicated, and postprandial conditions using the median of the area under the curve, the relative area under the curve and the main peak ***: The median of the area under the curve of the frequency range in the region between 2-8 cycles per minute (cpm) decreased from 4.7 cpm in the fasting condition to 4.0 cpm in the medicated state (t=3.32, P=0.004). This concurred with the decrease seen in the relative area under the FFT curve in the region from 4 to 8 cpm from 38.3% to 26.6% (t=2.81, P=0.012) and the increase in area in the region from 2 to 4 cpm from 22.4% to 27.7%, respectively (t=-2.5, P=0.022). Finally the main peak position also decreased in the region from 2 to 8 cpm. Main peak activity in the fasting state was 4.72 cpm and declined to 3.45 cpm in the medicated state (t=2.47, P=0.025). There was a decrease from the fasting state to the postprandial state at 3.02 cpm (t=4.0, P=0.0013). CONCLUSION: Short-term electrical bio-impedance can assess gastric motility changes in individuals experiencing gastric stress by analyzing the area medians and relative areas under the FFT curve.

关键词： Bio-impedance Fast Fourier Transform Gastric motility Metoclopramide Postprandial

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Preparation of a ε-caprolactonic diterpenoid derivate by unexpected oxidative cleavage/lactonization of 2-oxoaustroeupatol

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Natural Products and Bioprospecting 2022年第1期12卷 265-269页

作者： Pablo A.Chacón-morales Juan M.Amaro-Luis Luis Beltrán Rojas Fermín Rémi Jacquet Denis Deffieux Laurent Pouységu Stéphane Quideau Natural Products Laboratory Department of ChemistryFaculty of ScienceUniversity of Los AndesMérida 5101Venezuela Research Institute Faculty of Pharmacy and BioanalysisUniversity of Los AndesMérida 5101Venezuela ISM(CNRS-UMR 5255) Univ.Bordeaux351 cours de la Libération33405 Talence CedexFrance

From aerial parts of Austroeupatorium inulifolium was isolated the ent-nor-furano triol labdane austroeupatol *** compound 1 was treated with IBX showing an unexpected selectivity at the potentially oxidizable sites of the sub-strate yielding the 2-oxoaustroeupatol(2)and 2,19-dioxoaustroeupatol(3).The treatment of 2 with sodium periodate yields a heterocyclic derivative(ε-caprolactone derivate 4)formed by oxidative cleavage and unexpected intramo-lecular attack of the hydroxymethylene(C-19)oxygen to the ketonic carbon(C-2).A plausible mechanistic pathway for the obtention of compound 4 is proposed.

关键词： Oxidative cleavage Austroeupatol NaIO4 IBX Lactonization NMR

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