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High CO_(2)permeation using a new Ce_(0.85)gd_(0.15)O_(2-δ)-LaNiO_(3)composite ceramic–carbonate dual-phase membrane

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Journal of Environmental Sciences 2024年第6期140卷 219-229页

作者： Daniela gonzález-Varela JFrancisco gómez-garcía gustavo Tavizon Heriberto Pfeiffer Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCd.UniversitariaDel.CoyoacánCP 04510Ciudad de MéxicoMéxico Departamento de Física y Química Teórica Facultad de QuímicaUniversidad Nacional Autónoma de MéxicoCd.UniversitariaDel.CoyoacánCP 04510Ciudad de MéxicoMéxico 不详

This work shows the synthesis,characterization and evaluation of dense-ceramic membranes made of Ce_(0.85)gd_(0.15)O_(2-δ)-LaNiO_(3)(Cg-LN)composites,where the fluorite-perovskite ratio(Cg:LN)was varied as follows:75:25,80:20 and 85:15 wt.%.Supports were initially characterized by XRD,SEM and electrical conductivity(using vacuum and oxygen atmospheres),to determine the composition,microstructural and ionic-electronic conductivity ***,supports were infiltrated with an eutectic carbonates mixture,producing the corresponding dense dual-phase membranes,in which CO_(2)permeation tests were ***,CO_(2)permeation experiments were performed from 900 to 700℃,in the presence and absence of oxygen(flowed in the sweep membrane side).Results showed that these composites possess high CO_(2)permeation properties,where the O_(2)addition significantly improves the ionic conduction on the sweep membrane ***,the gC80-LN20 composition presented the best results due to the following physicochemical characteristics:high electronic and ionic conductivity,appropriate porosity,interconnected porous channels,as well as thermal and chemical stabilities between the composite support and carbonate phases.

关键词： CO_(2)permeation Doped CeO_(2) LaNiO_(3) Impedance Ceramic carbonate membrane

Prevalence of Helicobacter pylori infection among patients with esophageal carcinoma

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World Journal of gastroenterology 2024年第29期30卷 3479-3487页

作者： Miriam López-gómez Maria Morales Rebeca Fuerte Marta Muñoz Pedro-david Delgado-López Jorge Francisco gómez-Cerezo Enrique Casado Department of Medical Oncology Precision Oncology LaboratoryInfanta Sofía University HospitalSan Sebastián de los Reyes 28231MadridSpain Department of Medical Oncology Infanta Sofía University HospitalSan Sebastián de los Reyes 28702Spain Department of Internal Medicine Infanta Sofía University HospitalSan Sebastián de los Reyes 28703MadridSpain Department of Pathology Infanta Sofía University HospitalSan Sebastián de los Reyes 28702Spain Department of Neurosurgery Burgos University HospitalBurgos 09006Spain Department of Internal Medicine Infanta Sofía University Hospital and Henares University Hospital Foundation for Biomedical Research and InnovationSan Sebastian de los Reyes 28702MadridSpain Department of Medical Oncology Infanta Sofia University Hospital and Henares University Hospital Foundation for Biomedical Research and InnovationSan Sebastian de los Reyes 28702MadridSpain

BACKgROUND Helicobacter pylori(***)is a widespread microorganism related to gastric adenocarcinoma(AC).In contrast,it has been reported that an inverse association exists between *** infection and esophageal *** mechanisms underlying this supposedly protective effect remain *** To determine the prevalence of *** infection in esophageal carcinoma patients,we performed a retrospective observational study of esophageal tumors diagnosed in our *** We retrospectively reviewed the prevalence of *** infection in a cohort of patients diagnosed with esophageal *** or previous proton pump inhibitor(PPI)usage was also *** A total of 89 patients with esophageal carcinoma(69 males,77.5%),with a mean age of 66 years(range,26-93 years)were *** was the most frequent pathological variant(n=47,52.8%),followed by squamous cell carcinoma(n=37,41.6%).Fourteen ACs(29.8%)originated in the gastroesophageal junction and 33(70.2%)in the esophageal ***,54 patients(60.7%)presented at stages III and *** *** infection occurred only in 4 patients(4.5%),3 with AC(6.3%of all ACs)and 1 with squamous cell carcinoma(2.7%of all squamous cell tumors).all patients with previous *** infection had stage *** one patient had received prior *** eradication therapy,whereas 86(96.6%)had received previous or concomitant PPI *** In our cohort of patients,and after histologic evaluation of paraffin-embedded primary tumors,we found a very low prevalence of previous *** *** also reviewed the medical history of the patients,concluding that the majority had received or were on PPI *** minimal prevalence of *** infection found in this cohort of patients with esophageal carcinoma suggests a protective role.

关键词： Helicobacter pylori Eradication Esophageal tumor Dysbiosis Proton pump inhibitors Carcinogenesis Microbiota Incidence

Spark Plasma Sintering of Boron Carbide Using Ti_(3)SiC_(2) as a Sintering Additive

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 645-650页

作者： Hülya Biçer Mustafa Tuncer Hasan göçmez Iurii Bogomol Valerii Kolesnichenko Andrey Ragulya Kutahya Dumlupinar University School of EngineeringDepartment of Metallurgical and Materials EngineeringKütahya 43100Tur-key Boron Based Advanced Ceramics Application and Research Center Kütahya Dumlupınar UniversityKütahya 43100Turkey Advanced Technologies Center(İLTEM) Kütahya Dumlupınar UniversityKütahya 43000Turkey Department of High-Temperature Ma-terials and Powder Metallurgy National Technical University of Ukraine“Igor Sikorsky Kyiv Polytechnic Institute”Kyiv 03056Ukraine Frantsevich Institute for Problems of Materials Science National Academy of Sciences of UkraineKyiv 03056Ukraine

Boron carbide has unique properties for wide application possibilities;however,poor sinterability limits its *** approach to overcome this limitation is the addition of secondary phases into boron *** carbide based composite ceramics are produced by the direct addition of secondary phases into the structure or via reactive sintering using a sintering *** present study investigated the effect of Ti_(3)SiC_(2) addition to boron carbide by reactive spark plasma sintering in the range of 1700-1900℃.Ti_(3)SiC_(2) phase decomposed at high temperatures and reacted with B4C to form secondary phases of TiB2 and *** results demonstrated that the increase of Ti_(3)SiC_(2) addition(up to 15 vol%)effectively promoted the densification of B4C and yielded higher ***,as the amount of Ti_(3)SiC_(2) increased further,the formation of microstructural inhomogeneity and agglomeration of secondary phases caused a decrease in hardness.

关键词： reactive sintering SPS boron carbide MAX phase

Estimation of Equivalent Model of Photovoltaic Array Using Unscented Kalman Filters

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 819-827页

作者： M.A.gonzález-Cagigal JoséA.Rosendo-Macías A.gómez-Expósito the Department of Electrical Engineering University of SevilleSpainand A.Gómez-Expósito is also with ENGREEN Laboratory of Engineering for Energy and Environmental SustainabilitySevilleSpain

This paper proposes the use of the unscented Kalman filter to estimate the equivalent model of a photovoltaic(PV)array,using external measurements of current and voltage at the inverter *** estimated model is of interest to predict the power output of PV plants,in both planning and operation scenarios,and thus improves the efficient operation of power systems with high penetration of renewable *** proposed technique has been assessed in several simulated scenarios under different operating *** results show that accurate estimates are provided for the model parameters,even in the presence of measurement noise and abrupt variations under the external conditions.

关键词： Equivalent model parameter estimation photovoltaic energy unscented Kalman filter

Digital Social Connectedness as a Lifeline for Older People: Use and Non-use of VinclesBCN During the Pandemic

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International Journal of Disaster Risk Science 2024年第2期15卷 251-264页

作者： Israel Rodríguez‑giralt Daniel López‑gómez Roser Beneito‑Montagut CareNet IN3Universitat Oberta de Catalunya08018 BarcelonaSpain School of Social Sciences Cardif UniversityCardif CF103NSWalesUK

This article presents the results of a study that evaluated VinclesBCN during COVID-19. This digital-based public social service aims to prevent loneliness and isolation in +65-year-old adults living in Barcelona. Through service user(N = 12) and professional(N = 6) interviews and a questionnaire with service users(N = 255), we demonstrate the pivotal role of digital connectedness in transforming VinclesBCN into a lifeline during the pandemic. The analysis revealed the importance of sociability, social support, and, especially, entertainment in coping with pandemic fatigue and facilitating social connectivity and support among users. Users engaged in activities such as sharing images, songs, memes, and daily greetings to provide proximity, sociability, and care among users, whether they belonged to preexisting groups or were newly introduced to the platform. It also facilitated the identification of individuals who needed companionship, comfort, or more specialized support. The findings emphasize the significance of entertainment as a resilience-building strategy during times of uncertainty. Despite the positive impact, not all users equally used the platform. Non-use was strongly associated with being a woman, having a low educational level, having preexisting social relationships, less time of enrolment in the platform, as well as a high perception of loneliness, poor self-reported health, and low mood. The article underscores the need for further research into older adults' digital engagement during crises, its role in building resilience, and advocating for inclusive digital interventions that take into account diverse older adults' needs and experiences in crisis contexts.

关键词： Barcelona COVID-19 pandemic Digital social connectedness Entertainment Older adult resilience Public digital service

Anthropogenic mineral generation and its potential resource supply:The case of niobium

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Science China Earth Sciences 2024年第8期67卷 2583-2591页

作者： Xianlai ZENg Moisés gómez Mahmoud BAKRY Yong gENg Jinhui LI School of Environment Tsinghua UniversityBeijing 100084China School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of International and Public Affairs Shanghai Jiao Tong UniversityShanghai 200030China

The strategy of carbon neutrality is reshaping the global landscape of resource flow and *** the final sink of geological minerals,the proliferated anthropogenic minerals,also called secondary resources,play an increasingly important role in resource supply *** is a critical metal that lacks full concern for its *** fundamental principle of niobium circularity is to recycle and maintain the material as close to the manufacturing process as *** we estimate the niobium-containing applications lost at their end-of-life,underscoring the imperative to minimize such ***,we elucidate the extraction processes for scrap and alloy quantities throughout the industry's *** from anticipated waste generated by the majority of niobium applications,a forecast indicates a potential loss of approximately 168 kt by 2090 in the absence of ***,with a recycling efficiency of 90%for niobium,the projected loss diminishes to approximately 16 *** delve into the significance of niobium's circular economy and explore various aspects that demand further investigation for a seamless transition from linear to circular practices.

关键词： Niobium Anthropogenic mineral Circular economy Recycling Sustainability

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Low-power SiPM readout BETA ASIC for space applications

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Nuclear Science and Techniques 2024年第3期35卷 153-169页

作者： Anand Sanmukh Sergio gómez albert Comerma Joan Mauricio Rafel Manera Andreu Sanuy Daniel guberman Roger Catala albert Espinya Marina Orta Oscar de la Torre david gascon Departament de Física Quàntica i Astrofísica(FQA) Institut de Ciències del Cosmos(ICCUB)Universitat de Barcelona(UB)08028 BarcelonaSpain Institut d’Estudis Espacials de Catalunya(IEEC) 08034 BarcelonaSpain Electronics Department Serra Hunter fellow at Polytechnic University of Catalonia(UPC)08019 BarcelonaSpain

The BETA application-specific integrated circuit(ASIC)is a fully programmable chip designed to amplify,shape and digitize the signal of up to 64 Silicon photomultiplier(SiPM)channels,with a power consumption of approximately~1 mW/*** to its dual-path gain,the BETA chip is capable of resolving single photoelectrons(phes)with a signal-to-noise ratio(SNR)>5 while simultaneously achieving a dynamic range of~4000 ***,BETA can provide a cost-effective solution for the readout of SiPMs in space missions and other applications with a maximum rate below 10 *** this study,we describe the key characteristics of the BETA ASIC and present an evaluation of the performance of its 16-channel version,which is implemented using 130 nm *** ASIC also contains two discriminators that can provide trigger signals with a time jitter down to 400 ps FWHM for 10 *** linearity error of the charge gain measurement was less than 2%for a dynamic range as large as 15 bits.

关键词： Radiation detectors Silicon photomultipliers Photon sensors Front-end electronics Mixed-mode ASICs Space technology

Lifestyles of Older Adults in Castilla-La Mancha(Spain):Influence of Sex,Age,and Habitat

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Fudan Journal of the Humanities and Social Sciences 2024年第2期17卷 313-335页

作者： Esther Portal Martínez Juan Lirio Castro david alonso gonzález JoséLuis gómez Ramos University of Castilla-La Mancha Talavera de la ReinaSpain Complutense University MadridSpain

This paper presents the quantitative research results of a comprehensive study titled“Current Profle of Older Adults in Castilla-La Mancha(Spain).”The study aims to understand and describe the characteristics of individuals aged 65 and above within this autonomous region,with a focus on the variables of sex,age,and habitat.A cross-sectional approach was employed,utilizing quantitative methods to collect *** gather information,a customized questionnaire was developed to address the study objectives,covering various aspects such as sociodemographic factors,living conditions,leisure activities,social participation,and cultural *** survey was conducted via telephone,ensuring representation by employing gender quotas,age-group stratifcation,and considerations for habitat size.A representative sample of 1,065 participants was included in the *** fndings reveal a degree of homogeneity in the lifestyles of older adults,with discernible variations infuenced by factors such as sex,habitat,and *** results shed light on the diverse habits and experiences of older adults,emphasizing the signifcance of habitat conditions,social participation,and the aging process.

关键词： Lifestyle habits Older adults Habitat conditions Social participation Aging experience

Pollen analysis reveals the effects of uncovered interactions,pollen-carrying structures,and pollinator sex on the structure of wild bee-plant networks

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Insect Science 2024年第3期31卷 971-988页

作者： Clément Tourbez Carmelo gómez-Martínez MiguelÁngel gonzalez-Estévez Amparo Lazaro Mediterranean Institute for Advanced Studies(UIB-CSIC) Global Change Research GroupEsporlesBalearic IslandsSpain Department of Biology Ecology AreaUniversity of the Balearic/slandsPalmaSpain

Pollination networks are increasingly used to model the complexity of interactions between pollinators and flowering plants in *** methods exist to sample these interactions,with direct observations of plant-pollinator contacts in the field being by far the most *** the identification of pollen carried by pollinators allows uncovering interactions and increasing sample sizes,the methods used to build pollen-transport networks are variable and their effect on network structure remains *** understand how interaction sampling influences the structure of networks,we analyzed the pollen found on wild bees from eight communities across Mallorca Island and investigated the differences in pollen loads between bee body parts(scopa ***)and *** then assessed how these differences,as well as the uncovered interactions not detected in the field,influenced the structure of wild bee-plant *** identified a higher quantity and diversity of pollen in the scopa than in the rest of the female body,but these differences did not lead to differences in structure between plant-pollination(excluding scopa pollen)and bee-feeding interaction(including scopa pollen)***,networks built with pollen data were richer in plant species and interactions and showed lower modularity and specialization(H2'),and higher nestedness than visitation networks based on field *** interactions with plants were stronger compared to those of males,although not ***,females were more generalist(low d')and tended to be more central in interaction networks,indicating their more key role structuring pollination networks in comparison to *** study highlights the importance of palynological data to increase the resolution of networks,as well as to understand important ecological questions such as the differences between plant-pollination and bee-feeding interaction networks,and the role of sexes in pollination.

关键词： palynology pollen-transport networks pollination role of bee sexes sampling methodology visitation networks