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Use of δ^(18)O, δ^(13)C and nO_(3)^(-) to identify hydrogeochemical processes related to contamination in an aquifer located in central Mexico

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Acta Geochimica 2022年第3期41卷 367-392页

作者： Joséiv.n Morales-Arredondo María Aurora Armienta Hernández Fátima Juárez-Aparicio Jorge Federico landa-Arreguín Itzamna Zaknite Flores-Ocampo natural Resources Department Institute of GeophysicsNational Autonomous University of MexicoCiudad Universitaria No.3000Col.Copilco UniversidadCoyoacan Delegation04360 MexicoCDMXMexico Earth sciences Postgraduate Program University National Autonomous of MexicoUniversity City No.3000Col.Copilco UniversityCoyoacán Delegation04510 MexicoCDMXMexico

In this work,an isotopic analysis of δ^(18)O,δ^(13)C,and nO_(3)^(-) concentrations was carried out to identify the origin and the processes related to the contamination of an aquifer located in the state of Guanajuato,*** research identified the possible sources of δ^(13)C in *** groundwater flow,CO_(2) participates in different hydrogeochemical reactions in which the dissolution of carbonates or biochemical processes related to biodegradation stand *** data of δ^(13)C,δ^(18)O,and the hydrogeochemical behavior of nO_(3)^(-) and HCO_(3)^(-) in water,in addition to isotopic data and the chemical composition of limestones in the study area,were determined to establish the isotopic signature and the processes undergone by the *** isotopic signature of rock and water samples indicated that metamorphic limestones contributed with carbon dioxide to deep groundwater,while in the upper aquifer,bacterial metabolic reactions during nitrification–denitrification could modify the isotopic signature of δ^(13)C in some wells,although atmospheric contribution also plays a *** modification of the carbon isotopic component is related to the precipitation of calcite in specific regions of the study area,input of atmospheric CO_(2),and soil(*** possible participation of C4-type plants in the assimilation-release of carbon).This process is not confirmed or completely ruled out in this study since agriculture is excessively developed throughout the *** joint interpretation of isotopic values and the hydrogeochemical behavior of major and conservative elements help in identifying possible pollution processes in which different carbon sources are related.

关键词： ^(18)O and^(13)C isotopes Groundwater pollution nitrate limestone

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Changes in rainfall partitioning caused by the replacement of native dry forests of lithraea molleoides by exotic plantations of Pinus elliottii in the dry Chaco mountain forests, central Argentina

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Journal of Arid land 2020年第5期12卷 717-729页

作者： samia s CORTÉs Juan I WHITWORTH-HUlsE Eduardo l PIOVAnO Diego E GURVICH Patricio n MAGlIAnO land science Research Center(CICTERRA-COnICET)and national University of Córdoba Av.Vélez Sarsfield 1611X5016GCA CórdobaArgentina Multidisciplinary Institute of Plant Biology National University of Córdoba and CONICETCC 495X5000JJC CórdobaArgentina Environmental study Group Institute of Applied Maths of San LuisNational University of San Luis and CONICETEjército de los Andes 950D5700HHW San LuisArgentina Department of Biology Faculty of ChemistryBiochemistry and PharmacyNational University of San LuisEjército de los Andes 950D5700HHW San LuisArgentina

The replacement of native dry forests by commercial(exotic)tree plantations could generate changes in rainfall partitioning,which further affects the water *** this study,we determined(i)the rainfall partitioning into interception,throughfall and stemflow,(ii)the role of rainfall event size on rainfall partitioning,(iii)the pH of water channelized as throughfall and stemflow,and(iv)the runoff in lithraea molleoides(a native species)and Pinus elliottii(an exotic species)stands in the dry Chaco mountain forests,central *** average,interception,throughfall and stemflow accounted for 19.3%,79.5%and 1.2%of the gross rainfall in *** stand,and 32.6%,66.7%and 0.7%of the gross rainfall in *** stand,*** of interception,throughfall and stemflow presented positive linear relationships with the increment of rainfall event size for both tree species(Pn all cases).Percentages of interception,throughfall and stemflow were all related to the increment of rainfall event size,showing different *** increasing rainfall event size,interception exponentially decreased,throughfall asymptotically increased and stemflow linearly *** *** and *** stands presented significant differences in the pH values of water channelized as throughfall(6.3 vs.6.7,respectively;Pnd stemflow(4.5 vs.5.8,respectively;Pnoff occupied only 0.3%of the gross rainfall in *** stand and was zero in *** *** results showed that the native species *** presented 13.6%more water reaching the topsoil(i.e.,net rainfall;net rainfall=gross rainfall-interception-runoff)than the exotic species *** study improves our understanding of the effects of native vegetation replacement on the local water balance in the dry forest ecosystems.

关键词： drylands ecohydrology land use changes spatial heterogeneity water-limited environments

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A General Analytic Approximation Technique for the Modified Bessel Functions with Fractional Order iv (x), Applied to I1/6(x) and I1/7(x)

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Advances in Pure Mathematics 2024年第9期14卷 768-777页

作者： Jorge Olivares Pablo Martín Maria T. Veliz Departamento de Matemticas Universidad de Antofagasta Antofagasta Chile Departamento de Fsica Universidad de Antofagasta Antofagasta Chile

A general technique to obtain simple analytic approximations for the first kind of modified Bessel functions. The general procedure is shown, and the parameter determination is explained through the applications to this particular case I1/6(x)and I1/7(x). In this way, it shows how to apply the technique to any particular orderν, in order to obtain an approximation valid for any positive value of the variable x. In the present method power series and asymptotic expansion are simultaneously used. The technique is an extension of the multipoint quasirational approximation method, MPQA. The main idea is to look for a bridge function between the power and asymptotic expansion of the I1/6(x), and similar procedure for I1/7(x). To perform this, rational functions are combined with hyperbolic ones and fractional powers. The number of parameters to be determined for each case is four. The maximum relative errors are 0.0049 for ν=1/6, and 0.0047 for ν=7. However, these relative errors decrease outside of the small region of the variables, wherein the maximum relative errors are reached. There is a clear advantage of this procedure compared with any other ones.

关键词： Bessel Functions Power series Asymptotic Expansion MPQA Technique

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serum ferritin and the risk of early-onset colorectal cancer

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3496-3506页

作者： Adam l Urback Kylee Martens Hannah stowe McMurry Emerson Y Chen Caitlin Citti Anil sharma Adel Kardosh Joseph J shatzel Division of Internal Medicine Oregon Health&Science UniversityPortlandOR 97239United States Division of Hematology and Medical Oncology Knight Cancer InstituteOregon Health&Science UniversityPortlandOR 97239United States Division of Gastroenterology&Hepatology Oregon Health&Science UniversityPortlandOR 97239United States

BACKGROUnD The incidence of early-onset colorectal cancer(EO-CRC)is rising in the United states,and is often diagnosed at advanced *** serum ferritin is often incidentally discovered in young adults,however,the indication for endoscopy in EO-CRC is *** To compare serum ferritin between patients with EO-CRC and healthy controls(HCs),and examine the association of serum ferritin in EO-CRC with patient-and disease-specific *** A retrospective study of patientss with newly-diagnosed EO-CRC was conducted from 1/2013-12/*** were included if serum ferritin was measured within 2 years prior to 1 year following CRC histologic *** supplement the analysis,a cohort of HCs meeting similar inclusion and exclusion criteria were identified for comparison.A sensitivity analysis including only patients with serum ferritin obtained at or before diagnosis was separately performed to minimize risk of *** Among 85 patients identified with EO-CRC(48 females),the median serum ferritin level was 26 ng/ml(rangeng/ml).Compared to HCs(n=80211),there were a higher proportion of individuals with EO-CRC with serum ferritinng/ml(female 65%,male 40%)versus HCs(female 32.1%,male 7.2%)age 29-39 years(P=0.002 and Pspectively).stage iv disease was associated with significantly higher serum ferritin compared to less advanced stages(Pserum ferritin obtained before or at the time of diagnosis was lower than levels obtained after *** findings were confirmed in the sensitivity *** severe iron deficiency may indicate an increased risk of EO-CRC,particularly at earlier *** studies defining the optimal serum ferritin threshold and routine incorporation of serum ferritin in screening algorithms is essential to develop more effective screening strategies for EO-CRC.

关键词： Early-onset Young-onset Colorectal cancer Age Ferritin Iron deficiency

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Risk of cancer,with special reference to extra-intestinal malignancies,in patients with inflammatory bowel disease

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World Journal of Gastroenterology 2013年第48期19卷 9359-9365页

作者： Alicia Algaba iv.n Guerra ngel Castao Gema de la Poza Víctor M Castellano Montserrat lópez Fernando Bermejo Department of Gastroenterology Hospital Universitario de Fuenlabrada 28942 Madrid Spain Department of Pathology Hospital Universitario de Fuenlabrada28942 Madrid Spain

AIM:To determine the incidence and characteristics of intestinal and extra-intestinal cancers among patients with inflammatory bowel disease in a spanish hospital and to compare them with those of the local ***:This was a prospective,observational,7-year follow-up,cohort *** incidence,incidence rates based on person-years of follow-up and relative risk were calculated for patients with inflammatory bowel disease and compared with the background *** incidence of cancer was determined using a hospital-based data registry from Hospital Universitario de *** data and details about time from diagnosis of inflammatory bowel disease to occurrence of cancer,disease extent,inflammatory bowel disease treatment,cancer therapy and cancer evolution were also collected in the inflammatory bowel disease ***:Eighteen of 590 patients with inflammatory bowel disease developed cancer[cumulative incidence=3%(95%CI:1.58-4.52)vs 2%(95%CI:1.99-2.11)in the background population;RR=1.5;95%CI:0.97-2.29].The cancer incidence among inflammatory bowel disease patients was 0.53%(95%CI:0.32-0.84)per patient-year of *** with inflammatory bowel disease had a significantly increased relative risk of urothelial carcinoma(RR=5.23,95%CI:1.95-13.87),appendiceal mucinous cystadenoma(RR=36.6,95%CI:7.92-138.4),neuroendocrine carcinoma(RR=13.1,95%CI:1.82-29.7)and rectal carcinoid(RR=8.94,95%CI:1.18-59.7).Colorectal cancer cases were not ***:The overall risk of cancer did not significantly increase in our inflammatory bowel disease ***,there was an increased risk of urinary bladder cancer and,with less statistical power,an increased risk of appendiceal mucinous cystadenoma and of neuroendocrine *** cancer risk was low in our series.

关键词： Extra-intestinal cancer Inflammatory bowel disease Cancer risk Background population Urothelial carcinoma Appendiceal mucinous cystadenoma neuroendocrine carcinoma Rectal carcinoid

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25-hydroxycholecalciferol reverses heat induced alterations in bone quality in finisher broilers associated with effects on intestinal integrity and inflammation

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Journal of Animal science and Biotechnology 2022年第2期13卷 499-519页

作者： Huaiyong Zhang Maryam Majdeddin Djoere Gaublomme Bernard Taminiau Matthieu Boone Dirk Elewaut George Daube iv.n Josipovic Keying Zhang Joris Michiels laboratory for Animal nutrition and Animal Product Quality Department of Animal Sciences and Aquatic EcologyGhent University9000 GhentBelgium Key laboratory of Animal Disease-resistant nutrition Ministry of EducationInstitute of Animal NutritionSichuan Agricultural UniversityYa’an 611130SichuanChina Unit Molecular Immunology and Inflammation VIB Center for Inflammation ResearchGhent University and Department of RheumatologyGhent University Hospital9000 GhentBelgium Department of Food sciences-Microbiology University of Liège4000 LiègeBelgium Ghent University Centre for X-ray Tomography(UGCT) Ghent University9000 GhentBelgium Department of Physics and Astronomy Radiation Physics Research GroupGhent University9000 GhentBelgium

Background:Alterations in ambient temperature have been associated with multiple detrimental effects on broilers such as intestinal barrier disruption and dysbiosis resulting in systemic *** and 25-hydroxycholecalciferol(25-OH-D_(3))have shown to play a negative and positive role,respectively,in the regulation of bone *** the potential of 25-OH-D_(3)in alleviating heat induced bone alterations and its mechanisms was ***:Heat stress(Hs)directly induced a decrease in tibia material properties and bone mass,as demonstrated by lower mineral content,and Hs caused a notable increase in intestinal *** with dietary 25-OH-D_(3)reversed the Hs-induced bone loss and barrier *** suffering from Hs exhibited dysbiosis and increased expression of inflammatory cytokines in the ileum and bone marrow,as well as increased osteoclast number and *** changes were prevented by dietary 25-OH-D_(3)***,dietary 25-OH-D_(3)addition decreased abundance of B-and T-cells in blood,and the expression of inflammatory cytokines,especially TnF-α,in both the ileum and bone marrow,but did not alter the diversity and population or composition of major bacterial *** regard to bone remodeling,dietary 25-OH-D_(3)supplementation was linked to a decrease in serum C-terminal cross-linked telopeptide of type I collagen reflecting bone resorption and a concomitant decrement in osteoclast-specific marker genes expression(*** K),whereas it did not apparently change serum bone formation markers during ***:These data underscore the damage of Hs to intestinal integrity and bone health,as well as that dietary 25-OH-D_(3)supplementation was identified as a potential therapy for preventing these adverse effects.

关键词： Bone remodeling Hs Inflammation Intestinal barrier Tibial mass

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Geoid undulation modeling through the Cokriging methode——A case study of Guayaquil, Ecuador

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Geodesy and Geodynamics 2021年第5期12卷 356-367页

作者： iv.n Palacios Orejuela César leiva González Xavier Buenano Guerra Elena Chicaiza Mora Theofilos Toulkeridis Universidad de las Fuerzas Armadas EsPE SangolquíEcuador Universidad Politécnica de Madrid MadridSpain

The determination of vertical component plays a fundamental role in the initial phase of engineering applications. However, its acquisition is technically and economically demanding, mainly due to the precise heights relative to a reference surface, such as the mean sea level. The Cokriging technique is a necessary input for the calculation of the vertical component of the geodetic control points measured by Gnss, and it requires less auxiliary data and uses complementary available variables for the ***, the main goal is to use Cokriging to establish a geoid undulation prediction model for the rural area of the canton of Guayaquil, Ecuador. Ordinary, Residual and Universal Cokriging and Kriging techniques were used to compare their results and select the best for achieving accuracy. The validation of the application techniques yielded that Universal Cokriging was the most accurate with an RMsE of 8 cm and RsR of 2 cm, obtained just with 66 samples(20% of the dataset). Furthermore, considering the comparison with other regional geoid undulation models, the proposed model increased the accuracy of the results by a ratio of 9.68 and 6.96 in relation to EGM96 and EGM08, respectively.

关键词： Universal Cokriging Kriging Mean sea level Gnss

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The Difficult Airway: A new simplified Approach to an Old Complex Problem

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Open Journal of Anesthesiology 2017年第8期7卷 210-233页

作者： iv.n Mauricio Alvarado Arteaga Department of Anesthesiology Hospital de San Jose Bogotá Colombia

Difficult airway situations are a major cause of morbidity, mortality and malpractice claims in anesthetic practice and other critical care settings. Although infrequent, they are serious and complex situations where many variables interact. Among these variables, quick and accurate rescuer decision-making is a major outcome determinant. Emerging evidence, recent advances in technology and development of new devices have provided new tools to deal with the problem, but still, basic underlying principles of management remain. Based on the available evidence and expert consensus, multiple guidelines and algorithms have been published, but they may have limited applicability, contain confusing and ambiguous recommendations or address very specific clinical situations. This narrative review attempts to summarize, organize and consolidate current trends and supported recommendations of the updated guidelines in one practical, concise and unified guide, proposing a simple, intuitive and novel algorithm.

关键词： Anesthesia Airway Management Airway Obstruction Intubation-Intratracheal Pulmonary Ventilation Guideline Algorithms

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Coherent OnU based on 850 μm-long cavity-RsOA for next-generation ultra-dense access network

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Chinese Optics letters 2016年第5期14卷 19-23页

作者： Guang Yong Chu Adolfo lerín iv.n n.Cano Victor Polo Josep Prat Department of signal Theory and Communications Universitat Politècnica de Catalunya

In this letter, an efficient bidirectional differential phase-shift keying （DPsK）--DPsK transmission for a ultra- dense wavelength division-multiplexed passive optical network is proposed. A single distributed feedback laser at the optical network unit （OnU） is used both as the local laser for downlink coherent detection and the optical carrier for uplink. Phase-shift keying is generated using a low-cost reflective semiconductor optical amplifier （RsOA） at the OnU. The RsOA chip has the bandwidth of 4.7 GHz at the maximum input power and bias current. For uplink transmission, the sensitivity of the RsOA chip reaches -48.2 dBm at the level of bit error rate = 10^-3 for back-to-back, and the penalty for 50 km transmission is less than 1 dB when using polarization diversity.

关键词： OnU RsOA Coherent OnU based on 850 m-long cavity-RsOA for next-generation ultra-dense access network

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Alluvial sedimentation and tectonostratigraphic evolution in a narrow extensional zigzag basin margin (northern Teruel Basin, spain)

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Journal of Palaeogeography 2019年第4期8卷 368-392页

作者： lope Ezquerro Aránzazu luzón José l.simón Carlos l.liesa Departamento de Ciencias de la Tierra Facultad de Ciencias Geotransfer Research Group and Instituto de Investigación en Ciencias Ambientales (IUCA) Universidad de Zaragoza

The northern part of the eastern margin of the extensional neogene Teruel Basin(central-eastern spain)consists of a non-linear,zigzag fault zone made of alternating ca.2 km long,nnW-ssE trending segments and shorter nnEssW *** outcrop conditions made possible a comprehensive integrated stratigraphic and structural study,especially focused on coarse clastic sediments deposited along the basin ***-exposed stratal relationships with boundary faults,allowed the analysis of tectonic influence on *** deformation includes growth faulting,rollover anticlines,and monoclines and associated onlap stratal terminations,angular unconformities,and other complex growth strata *** of them is the onlap-over-rollover bed arrangement described here for the first time,which reveals the competition between tectonic subsidence and sedimentary ***,the structural inheritance(dense Mesozoic fracture grid)and the dominant,nearly‘multidirectional’(σ1 vertical,σ2≈σ3),Pliocene extensional regime withσ3 close to E-W,are considered to have controlled the margin structure and ***-stratigraphic evolution includes:(i)reactivation of inherited nnW-ssE faults and development of W-sW-directed small alluvial fans(sAF)while nnE-ssW segments acted as gentle relay ramp zones;(ii)progressive activation of nnE-ssW faults and development of nW-directed very small alluvial fans(VsAF);during stages i and ii sediments were trapped close to the margin,avoiding widespread progradation;(iii)linking of nnW-ssE and nnE-ssW structural segments,overall basin sinking and widespread alluvial progradation;(iv)fault activity attenuation and alluvial *** particular structure and kinematic evolution of this margin controlled alluvial system *** of alluvial fans,directly set up at the border faults,was conditioned by the narrowness of the margin,small catchment areas,and proximity between faults,which prevented the development of l

关键词： Extensional basin Alluvial fan stratal stacking pattern structural inheritance Fault linkage

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