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A facile one-pot hydrothermal synthesis as an efficient method to modulate the potassium content of cryptomelane and its effects on the redox and catalytic properties

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Chinese Journal of Catalysis 2019年第6期40卷 940-952页

作者： Huiyan Pan Xiaowei Chen Oihane sanz Miguel A.Cauquia Jose M.rodriguez-Izquierdoa juan J.Delgado Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica Facultad de CienciasUniversidad de CádizCampus Río San PedroPuerto Real(Cádiz)E-11510Spain Applied Chemistry Department University of Basque Country(UPV-EHU)Apdo.1072San Sebastian20080Spain

Cryptomelane has been widely applied as catalyst in oxidation reactions due to its excellent redox properties and low ***,a novel one-pot hydrothermal synthesis using a potassium permanganate aqueous solution as precursor and ethanol as reducing agent has successfully been developed to obtain cryptomelane *** synthetic route makes it possible to control the amount of potassium incorporated into the structure of the cryptomelane by selecting the appropriate synthesis temperature and ethanol initial *** advantage of this approach,the effect of potassium concentration on the structural stability and reducibility of the cryptomelane,which are poorly discussed in the literature,has been *** have observed that samples with low content of potassium(~11%)show high conversions of CO to CO2 especially at low *** lower activity of the samples with high K contents(~16%)can be ascribed to the beneficial effect of K on the structural stability of cryptomelane in detriment of labile oxygen on cryptomelane surface.

关键词： Cryptomelane Pyrolusite Catalytic CO oxidation Hydrothermal synthesis Potassium content

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非正式学习环境中的STEM教育:美国博物馆学习服务案例研究

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世界教育信息 2024年第6期37卷 44-52页

作者：杨娟欧阳媛中国农业大学高等教育研究中心北京100091 首都师范大学教育学院北京100089

非正式学习环境为STEM教育提供了独特的机会和资源。作为非正式学习环境的典型代表,美国博物馆以知识共享为使命,通过策划丰富多样的教育活动,为各年龄段学生提供有针对性的STEM教育资源。研究聚焦于美国国家自然历史博物馆、旧金山探... 详细信息

非正式学习环境为STEM教育提供了独特的机会和资源。作为非正式学习环境的典型代表,美国博物馆以知识共享为使命,通过策划丰富多样的教育活动,为各年龄段学生提供有针对性的STEM教育资源。研究聚焦于美国国家自然历史博物馆、旧金山探索博物馆和西雅图飞行博物馆在STEM教育领域的实践探索,归纳总结了美国博物馆在提供STEM学习资源,与学校STEM教育有效衔接,支持STEM教师专业发展,吸引家庭参与STEM教育,促进STEM教育公平等方面的经验,这些经验为我国发展非正式学习环境中的STEM教育,丰富STEM教育资源提供了良好的借鉴。

关键词：非正式学习环境 STEM教育博物馆学习服务

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Anemia and digestive diseases: An update for the clinician

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World Journal of Gastroenterology 2009年第37期15卷 4615-4616页

作者： fernando Gomollón Javier P Gisbert Digestive Diseases Service Clinical University Hospital CIBEREHD IACS Avenida San Juan Bosco 15 Zaragoza 50009 Spain Digestive Diseases Service University Hospital "La Princesa" CIBEREHD C/ Diego León 62 Madrid 28006 Spain

Anemia and iron deficiency are so common in digestive diseases that often are underestimated and undertreated. Our goal is to review from classif ication to treatment of the diverse types of anemias in different digestive diseases to update our knowledge on diagnosis and treatment. With the goal of improving the prognosis and quality of life of digestive diseases patients, we will review current transfusion, intravenous iron, and erythropoietin roles in the treatment of anemia.

关键词： Anemia Iron deficiency Inflammatory bowel disease Crohn's disease Ulcerative colitis

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废弃气雾剂处理装置的研制

合成材料老化与应用 2024年第5期53卷 76-77页

作者：雷祖碧钟焕荣李树娟黄伟赵军范伟检潘三梅广州合成材料研究院有限公司广东广州510665

鉴定机构进行气雾剂危险性鉴定时产生大量的废弃气雾剂,这些废弃气雾剂需专门的回收装置进行处理,促使项目组加紧研制废弃气雾剂回收处理装置。该文介绍了一台废弃气雾剂处理装置的设计思路,增加了远程控制与水浴冷却功能,提高了该装置... 详细信息

鉴定机构进行气雾剂危险性鉴定时产生大量的废弃气雾剂,这些废弃气雾剂需专门的回收装置进行处理,促使项目组加紧研制废弃气雾剂回收处理装置。该文介绍了一台废弃气雾剂处理装置的设计思路,增加了远程控制与水浴冷却功能,提高了该装置的安全性与可靠性,并就废弃气雾剂回收注意事项做了说明。

关键词：废弃气雾剂处理装置废弃气雾剂回收安全性可靠性

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Experience with the surgical treatment of hepatic hydatidosis: Case series with follow-up

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World Journal of Gastroenterology 2010年第26期16卷 3305-3309页

作者： Hector Losada Morales Luis Burgos san juan Jorge Silva Abarca Cesar Muoz Castro Department of Surgery Universidad de La Frontera Hepato Pancreatic and Biliary Surgery Hospital Hernán Henríquez Aravena Department of Surgery Clínica Alemana de Temuco

AIM: To describe patient characteristics and the results of surgical treatment for hepatic hydatidosis (HH) in the Hospital Hernán Henríquez Aravena from December 2001 to March 2005. METHODS: Subjects older than 16 years with suspected HH were included based on the clinical picture and radiological studies. Variables examined included clinical and laboratory aspects, outcome, features of the parasite and surgical aspects. Descriptive statistics were used, calculating central tendency, dispersion and extreme tendency. RESULTS: The series was comprised of 122 patients, with an average age of 44 ± 16.9 years. The most frequently used surgical technique was subtotal cys-tectomy in 90% of the patients, followed by hepatic resection (hepatectomy, segmentectomy and subsegmentectomy) in 5%. In 2%, a combination of subtotal cystectomy and segmentectomy was performed. In addition, 28% of the series presented complications in the postoperative period and mortality was 2%. CONCLUSION: The most frequently used surgical technique for HH was subtotal cystectomy and the morbidity and mortality rates in this Chilean series are comparable to other national and international series.

关键词： Echinococcosis of liver Surgery Cases series Mortality Morbidity

Variation in SARS-CoV-2 seroprevalence in children in the region of Asturias,Northern Spain

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World Journal of Pediatrics 2022年第12期18卷 835-844页

作者： Elisa García-García Mercedes rodríguez-Pérez David Pérez-Solís Carlos Pérez-Méndez Cristina Molinos-Norniella Ángeles Cobo-Ruisánchez Eva María Fernández Fernández Noelia García González Laura Calle-Miguel Pediatrics Department Centro de Salud LaviadaCalle Juanín de Mieres833207GijónSpain Microbiology Department Hospital Universitario Central de AsturiasOviedoSpain Pediatrics Department Hospital Universitario San AgustínAvilésSpain Pediatrics Department Hospital Universitario de CabueñesGijónSpain Pediatrics Department Hospital Carmen y Severo Ochoa.Cangas del NarceaSpain Pediatrics Department Centro de Salud TeatinosOviedoSpain Pediatrics Department Hospital Universitario Central de AsturiasOviedoSpain

Background Updated seroprevalence estimates are important to describe the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)landscape and to guide public health *** aims are to describe longitudinal changes in seroprevalence in children in a region in Northern Spain and to analyze factors associated with SARS-CoV-2 *** Prospective multicenter longitudinal study with subjects recruited from July to September ***(up to 14 years old)were included and followed up until September *** blood samples were collected every six months during three testing rounds and were analyzed for SARS-CoV-2 *** data regarding epidemiological features,contact tracing,symptoms,and virological tests were *** evolution of SARS-CoV-2 seroprevalence during the study and the differences between children with positive and negative SARS-CoV-2 antibody tests were *** Two hundred children were recruited(50.5%girls,median age 9.7 years).The overall seroprevalence increased from round 1[1.5%,95%confidence interval(CI)0.3%–4.3%]to round 2(9.1%,95%CI 4.6%–12.7%)and round 3(16.6%,95%CI 9.5%–19.6%)(P<0.001).Main changes occurred in children aged zero to four years(P=0.001)who lived in urban areas(P<0.001).None of the children who were previously positive became *** multivariable analysis,three variables independently associated with SARS-CoV-2 seropositivity were identified:close contact with coronavirus disease 2019(COVID-19)confirmed or suspected cases[odds ratio(OR)=3.9,95%CI 1.2–12.5],previous positive virological test(OR=17.1,95%CI 3.7–78.3)and fatigue(OR=18.1,95%CI 1.7–193.4).Conclusions SARS-CoV-2 seroprevalence in children has remarkably increased during the time of our *** was the only COVID-19-compatible symptom that was more frequent in seropositive than in seronegative children.

关键词： Antibodies Child COVID-19 Seroepidemiologic studies

Novel Tandem Three Consecutive Reactions: Aza-Wittig, Imine Condensation and Electrophilic Aromatic Substitution Strategy to Indolizine Synthesis

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International Journal of Organic Chemistry 2021年第2期11卷 55-71页

作者： Julio C. González-rodríguez Carlos González-Romero Erick Cuevas-Yáñez juan J. Mejía Vega Christopher K. Jankowski David Corona-Becerril Centro Conjunto de Investigación en Química Sustentable (CCIQS) UAEM-UNAM Universidad Autónoma del Estado de México Unidad San Cayetano Toluca de Lerdo México Departamento de Química Orgánica Facultad de Química Universidad Autónoma del Estado de México Paseo Colón/Paseo Tollocan s/n Toluca Estado de México México Department de Chimie et Biochimie Université de Moncton Moncton Canadá

Reaction of ethyl (Z)-3-(heteroaryl/aryl)-2-((triphenyl-λ5-phosphaneylidene) amino) acrylates intermediates with 2,3-thiophenedicarboxaldehyde was used in novel Tandem three consecutive reactions: aza-Wittig, imine condensation and electrophilic heteroaromatic cyclization to obtain a series of indolizines. A tentative mechanism of this reaction is proposed.

关键词： Iminophosphorane Tandem Reaction Indolizine Synthesis

Forecasting Short Time Series with Missing Data by Means of Energy Associated to Series

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Applied Mathematics 2015年第9期6卷 1611-1619页

作者： Cristian rodríguez Rivero Julián Pucheta Sergio Laboret Daniel Patino Víctor Sauchelli Department of Electronic Engineering Universidad Nacional de CordobaCordobaArgentina Institute of Automatic Universidad Nacional de San JuanSan JuanArgentina

In this work an algorithm to predict short times series with missing data by means energy associated of series using artificial neural networks (ANN) is presented. In order to give the prediction one step ahead, a comparison between this and previous work that involves a similar approach to test short time series with uncertainties on their data, indicates that a linear smoothing is a well approximation in order to employ a method for uncompleted datasets. Moreover, in function of the long- or short-term stochastic dependence of the short time series considered, the training process modifies the number of patterns and iterations in the topology according to a heuristic law, where the Hurst parameter H is related with the short times series, of which they are considered as a path of the fractional Brownian motion. The results are evaluated on high roughness time series from solutions of the Mackey-Glass Equation (MG) and cumulative monthly historical rainfall data from san Agustin, Cordoba. A comparison with ANN nonlinear filters is shown in order to see a better performance of the outcomes when the information is taken from geographical point observation.

关键词： Artificial Neural Networks Rainfall Forecasting Energy Associated to Time Series Hurst’s Parameter

Association between Vitamin D Levels and the Risk of Metabolic Syndrome in a Rural Chinese Population

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Biomedical and Environmental Sciences 2021年第4期34卷 330-333页

作者： SUN Hua Lei LONG Shao Rong FU san Xian CHEN Gai Yun WANG Ya juan LIANG Rui WANG Su Fan ZHANG Li Ke ZHOU Li Wei LU Quan Jun LI Wen Jie Department of Nutrition the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450001HenanChina Department of Pathogenic Biology College of Basic Medicine of Zhengzhou UniversityZhengzhou 450001HenanChina Department of Nutrition and Food Hygiene College of Public Health of Zhengzhou UniversityZhengzhou 450001HenanChina

Metabolic syndrome(MS)is a cluster of metabolic abnormalities that include obesity,dyslipidemia,hyperglycemia,and high blood pressure(BP)[1].Previous studies have shown that the prevalence of MS is increasing in both developing and developed countries[2].Currently,about a quarter of the adult population worldwide have MS,which has become a serious global public health problem.

关键词： Metabolic obesity Rural

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