检索结果-南通市图书馆

How does anodization time affect morphological and photocatalytic properties of iron oxide nanostructures?

在线全文

学校读者我要写书评

暂无评论

Journal of materials Science & Technology 2020年第3期38卷 159-169页

作者： Bianca Lucas-Granados Rita Sánchez-Tovar Ramón mFernández-Domene josémaría Estívalis-martínez joséGarcía-Antón Ingeniería Electroquímica y Corrosión(IEC).Instituto Universitario de Seguridad Industrial Radiofísica y Medioambiental(ISIRYM)Universitat Politècnica de ValènciaCamino de Vera s/n46022ValenciaSpain Departmento de Ingeniería Química Universitat de ValènciaAv de les Universitatss/n46100 BurjassotSpain

Iron oxide nanostructures are promising materials to be used as photocatalysts in different photoelectrochemical applications. There are different techniques in order to synthesize these nanostructures, but one of the most inexpensive and simple method is electrochemical anodization. This method can lead to different nanostructures by controlling its parameters. Anodization time is one of the most critical parameters since it considerably affects the properties of the obtained nanostructures. In this work, different anodization times(5, 10, 15, 30 and 60 min) were studied. The resulting nanotubes were characterized by field emission scanning electron microscopy, Raman laser confocal microscopy, water splitting measurements, mott-Schottky analysis and electrochemical impedance spectroscopy, in order to test their viability for being used as photocatalysts in photoelectrochemical applications. Results showed that the best photocurrent density values in water splitting tests(0.263 m A m-2) were achieved for the sample anodized for 10 min under hydrodynamic conditions.

关键词： Iron oxide metallic nanostructures Photoelectrochemistry Anodization Time

Nutritional supplements use in high-performance athletes is related with lower nutritional inadequacy from food

在线全文

学校读者我要写书评

暂无评论

Journal of Sport and Health Science 2016年第3期5卷 368-374页

作者： mónica Sousa maria J.Fernandes Pedro Carvalho josé Soares Pedro moreira Vitor Hugo Teixeira Centre of Research Education Innovation and Intervention in Sport Faculty of Sport University of Porto Faculty of Nutrition and Food Sciences University of Porto Research Centre on Physical Activity Health and Leisure Faculty of Sport University of Porto

Background: The use of nutritional supplements(NS) among athletes is widespread. However, little is known about the relationship between nutritional adequacy and NS usage. The aims of this study were to evaluate the NS usage and to compare the nutritional intake from food and prevalence of micronutrient inadequacy(PmI) between NS users and ***: Portuguese athletes from 13 sports completed an NS usage questionnaire and a semi-quantitative food-frequency questionnaire assessing information over the previous 12 months. The estimated average requirement cut-point method was used to calculate PmI. General linear models were used to compare nutritional intake and NS usage. Chi-squared tests and logistic regression were performed to study, respectively,relationships and associations between PmI and NS ***: From the 244 athletes(66% males, 13–37 years), 64% reported NS usage. After adjustment, NS users showed a higher intake from food(p mI were seen for vitamins D and E, calcium, folate,and magnesium. After adjustment, NS users, irrespective of gender, reported lower PmI for calcium(OR = 0.28, 95%CI: 0.12–0.65), and female users for magnesium(OR = 0.06, 95%CI: 0.00–0.98).Conclusion: Athletes using NS reported a higher nutritional intake from food, and a lower PmI for several nutrients. Perhaps, those who were taking NS were probably the ones who would least benefit from it.

关键词： Carbohydrates minerals Proteins Sport Vitamins

Role of artificial intelligence in multidisciplinary imaging diagnosis of gastrointestinal diseases

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2021年第27期27卷 4395-4412页

作者： m Alvaro Berbís josé Aneiros-Fernández F Javier mendoza Olivares Enrique Nava Antonio Luna Department of R&D HT MédicaMadrid 28046MadridSpain Department of Pathology Hospital Universitario Clínico San CecilioGranada 18012Spain Department of Gastroenterology Fatima ClinicSevilla 41012Spain Department of Communications Engineering University of MálagaMalaga 29016Spain mRI Unit Department of RadiologyHT MédicaJaén 23007Spain

The use of artificial intelligence-based tools is regarded as a promising approach to increase clinical efficiency in diagnostic imaging,improve the interpretability of results,and support decision-making for the detection and prevention of ***,endoscopy and pathology images are suitable for deep-learning analysis,potentially changing the way care is delivered in *** aim of this review is to examine the key aspects of different neural network architectures used for the evaluation of gastrointestinal conditions,by discussing how different models behave in critical tasks,such as lesion detection or characterization(*** distinction between benign and malignant lesions of the esophagus,the stomach and the colon).To this end,we provide an overview on recent achievements and future prospects in deep learning methods applied to the analysis of radiology,endoscopy and histologic whole-slide images of the gastrointestinal tract.

关键词： Artificial intelligence machine learning Radiology Endoscopy Pathology Gastroenterology

The tip of the iceberg:ROP2 directly interacts with SYP121 to regulate root-hair polarization,elongation,and exocytosis

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

molecular Plant 2022年第7期15卷 1084-1086页

作者： martiniano m.Ricardi jose m.Estevez Instituto de Fisiología Biología Molecular y Neurociencias(IFIBYNE-UBA-CONICET)and Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresCiudad UniversitariaBuenos Aires C1428EHAArgentina Fundación Instituto Leloir and IIBBA-CONICET.Av.Patricias Argentinas 435 Buenos Aires C1405BWEArgentina Centro de Biotecnología Vegetal Facultad de Ciencias de la VidaUniversidad Andres BelloSantiago 8370146Chile ANID-millennium Science Initiative Program-millennium Nucleus for the Development of Super Adaptable Plants(mN-SAP) Santiago 8370146Chile

Root hairs(RHs)grow in a polar manner as cylindrical protrusions from the root *** significantly expand the root volume in the rhizosphere to search for water and nutrients,anchor the plant,and promote interactions with several kinds of microorganisms in the ***,the epidermis cell type responsible for RH development,switch from anisotropic cell elongation to tip growth through polarization of the growth machinery to a predefined RH initiation domain(RHID)at the plasma membrane.

关键词： tip polarization cylindrical

Disturbance and forest recovery in the monarch Butterfly Biosphere Reserve,mexico

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Forestry Research 2020年第5期31卷 1551-1566页

作者： jose Lopez-Garcıa Rafael m.Navarro-Cerrillo Instituto de Geografıa Universidad Nacional Autonoma de MexicoCiudad UniversitariaC.P.04510 CoyoacanDFMexico Departamento de Ingenierıa Forestal Universidad de CordobaCampus de RabanalesCarretera Nacional IV km 39614014 CordobaSpain

Analysis of the change in forest cover is important to determine stand dynamics and the processes involved in disturbance and *** of the core zone of the monarch Butterfly Biosphere Reserve were studied using photo interpretation techniques,considering biennial changes between 1999 and 2013 and changes over the whole period of study 1999–*** matrices were elaborated to determine the processes of change involved in both recovery and *** biennial changes for the whole period amounted to 2274 ha;343 ha accounted as degraded in more than one biennial *** total changes in forest cover between 1999 and 2013 involved 4902 ha,out of which,2912 ha were affected by disturbance,and 1990 ha were *** density and 2013 vegetation cover maps,the overall accuracy was 95.6%and 90.2%,*** combining both maps,gradual processes were revealed that were not evident in separate *** methodology is useful for the management and conservation of natural protected areas.

关键词： Illegal logging Forest density change Forest recovery Conifer forests monarch Butterfly Biosphere Reserve

An update on iron physiology

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2009年第37期15卷 4617-4626页

作者： manuel muoz Isabel Villar josé Antonio García-Erce Transfusion medicine School of Medicine University of Málaga Málaga 29071 Spain Department of Hospital Pharmacy University Hospital Miguel Servet Zaragoza 50009 Spain Hematology and Hemotherapy University Hospital Miguel Servet Zaragoza 50009 Spain

Iron is an essential micronutrient, as it is required for adequate erythropoietic function, oxidative metabolism and cellular immune responses. Although the absorption of dietary iron (1-2 mg/d) is regulated tightly, it is just balanced with losses. Therefore, internal turnover of iron is essential to meet the requirements for erythropoiesis (20-30 mg/d). Increased iron requirements, limited external supply, and increased blood loss may lead to iron deficiency (ID) and iron-deficiency anemia. Hepcidin, which is made primarily in hepatocytes in response to liver iron levels, inflammation, hypoxia and anemia, is the main iron regulatory hormone. Once secreted into the circulation, hepcidin binds ferroportin on enterocytes and macrophages, which triggers its internalization and lysosomal degradation. Thus, in chronic inflammation, the excess of hepcidin decreases iron absorption and prevents iron recycling, which results in hypoferremia and iron-restricted erythropoiesis, despite normal iron stores (functional ID), and anemia of chronic disease (ACD), which can evolve to ACD plus true ID (ACD + ID). In contrast, low hepcidin expression may lead to iron overload, and vice versa. Laboratory tests provide evidence of iron depletion in the body, or reflect iron-deficient red cell production. The appropriate combination of these laboratory tests help to establish a correct diagnosis of ID status and anemia.

关键词： Iron metabolism Iron deficiency Functionaliron deficiency, Hepcidin Anemia of chronic disease

Ferroelectricity Induced by Oxygen Vacancies in Rhombohedral ZrO_(2) Thin Films

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy & Environmental materials 2024年第1期7卷 229-237页

作者： Veniero Lenzi josé P.B.Silva Břetislav Šmíd Vladimir matoín Cosmin m.Istrate Corneliu Ghica Judith L.macmanus-Driscoll Luís marques Physics Center of minho and Porto Universities(CF-Um-UP) University of MinhoCampus de Gualtar 4710-057Braga Portugal Laboratory of Physics for materials and Emergent Technologies LapMETUniversity of Minho4710-057Braga Portugal Department of Surface and Plasma Science Faculty of Mathematics and PhysicsCharles UniversityV Holešovičkách 218000Prague 8 Czech Republic National Institute of materials Physics 105 bis Atomistilor 077125Magurele Romania Department of materials Science and metallurgy 27 Charles Babbage Rd.Cambridge CB3 OFSUK

Rhombohedral phase Hf_(x)Zr_(1.x)O_(2)(HZO,x from 0 to 1)films are promising for achieving robust ferroelectric polarization without the need for an initial wake-up pre-cycling,as is normally the case for the more commonly studied orthorhombic ***,a large spontaneous polarization observed in rhombohedral films is not fully understood,and there are also large discrepancies between experimental and theoretical *** this work,in rhombohedral ZrO_(2)thin films,we show that oxygen vacancies are not only a key factor for stabilizing the phase,but they are also a source of ferroelectric polarization in the *** is shown experimentally through the investigation of the structural properties,chemical composition and the ferroelectric properties of the films before and after an annealing at moderate temperature(400℃)in an oxygen environment to reduce the V_(o)concentration *** experimental work is supported by density functional theory(DFT)calculations which show that the rhombohedral phase is the most stable one in highly oxygen defective ZrO_(2)*** DFT calculations also show that V_(o)contribute to the ferroelectric *** findings reveal the importance of V_(o)for stabilizing rhombohedral ZrO_(2)thin films with superior ferroelectric properties.

关键词： charged defects ferroelectric polarization rhombohedral phase stability zirconia

Dendritic Growth, Eutectic Features and Their Effects on Hardness of a Ternary Sn–Zn–Cu Solder Alloy

在线全文

学校读者我要写书评

暂无评论

Acta metallurgica Sinica(English Letters) 2017年第6期30卷 528-540页

作者： Bismarck Luiz Silva Rodrigo Valenzuela Reyes Amauri Garcia joséEduardo Spinelli Department of materials Engineering Federal University of Rio Grande do Norte-UFRNNatalRN 59078-970Brazil Department of materials Engineering Federal University of Sao Carlos-UFSCarSao CarlosSP 13565-905Brazil Department of manufacturing and materials Engineering University of CampinasUNICAMPCampinasSP 13083-860Brazil

The present investigation is based on the results of a directionally solidified （DS） Sn-9 wt%Zn-2 wt%Cu alloy, including primary/secondary/tertiary dendrite arm spacings of the Sn-rich matrix, the morphologies of the eutectic mixture and the corresponding interphase spacing, the nature and proportion of the Cu-Zn intermetallic compound （ImC）. The main purpose is to establish interrelations of these microstructure features with experimental solidification thermal parameters, such as cooling rates and growth rates （v）, macrosegregation and hardness. Such interrelations are interesting for both industry and academy since they represent a tool permitting the preprogramming of final properties based on the design of the microstructure. In the case of Sn-Zn-Cu alloys, hardly anything is known about the combined effects of the length scale of the microstructure and fraction and distribution of the primary ImC on hardness. The alloy microstructure is composed of a β-Sn dendritic region, surrounded by a eutectic mixture of α-Zn and β-Sn phases and the γ-Cu5Zn8 ImC. The eutectic interphase spacing varies in the range 1.2-3.6 μm, with the α-Zn phase having a globular morphology for ν 〉 0.5 mm/s and a needle-like morphology for ν 〈 0.3 mm/s. A modified Hall-Petch-type experimental expression relating hardness to the interphase spacing is proposed.

关键词： Sn-Zn-Cu solder alloy Solidification microstructure Eutectic morphology Hardness

Efficacy of medium-chain fatty acid salts distilled from coconut oil against two enteric pathogen challenges in weanling piglets

在线全文

学校读者我要写书评

暂无评论

Journal of Animal Science and Biotechnology 2020年第1期11卷 251-267页

作者： Paola López-Colom Lorena Castillejos Agustina Rodríguez-Sorrento mónica Puyalto Juan josémallo Susana maría martín-Orúe Animal Nutrition and Welfare Service Animal and Food Science DepartmentFacultat de VeterinàriaUniversitat Autònoma de BarcelonaBellaterraSpain Norel S.A MadridSpain.

Background:The search for alternatives to antibiotics in pig production has increased the interest in natural resources with antimicrobial properties,such as medium-chain fatty acids(mCFA)as in-feed *** study evaluated the potential of a novel blend of mCFA salts(DIC)from distilled coconut oil with a lauric acid content to reduce enteropathogens and control intestinal diseases around *** experimental disease models were implemented in early-weaned piglets,consisting of two oral challenges:Salmonella Typhimurium(1.2×10~8 CFU)or enterotoxigenic Escherichia coli(ETEC)F4(1.5×10~9 CFU).The parameters assessed were:animal performance,clinical signs,pathogen excretion,intestinal fermentation,immune-inflammatory response,and intestinal ***:The Salmonella challenge promoted an acute course of diarrhea,with most of the parameters responding to the challenge,whereas the ETEC F4 challenge promoted a mild clinical course.A consistent antipathogenic effect of DIC was observed in both trials in the hindgut,with reductions in Salmonella *** counts in the cecum(P=0.03)on d 8 post-inoculation(PI)(Salmonella trial),and of enterobacteria and total coliform counts in the ileum and colon(Pmicrobiota(16 S rRNA gene sequencing),this additive tended(P=0.13)to reduce the Firmicutes/Bacteroidetes ratio and enriched Fibrobacteres after the Salmonella *** the ETEC F4 challenge,DIC prompted structural changes in the ecosystem with increases in Dialister,and a trend(P=0.14)to increase the Veillonellaceae *** parameters such as the intestinal fermentation products or serum pro-inflammatory mediators were not modified by DIC supplementation,nor were the histological *** the intraepithelial lymphocyte(IEL)counts were lowered by DIC in animals challenged with Salmonella(P=0.07).With ETEC F4,the IEL counts were higher with DIC on d 8 PI(P=0.08).Conclusions:This study c

关键词： Enteric pathogen Gut microbiota Intestinal immunity medium-chain fatty acids Weaning pig