检索结果-南通市图书馆

Investigating local corrosion processes of magnesium alloys with scanning probe electrochemical techniques: A review

引用

Journal of magnesium and Alloys 2022年第11期10卷 2997-3030页

作者： mara Cristina Lopes de Oliveira Rejane maria Pereira da Silva ricardo m.souto Renato Altobelli Antunes Federal University of ABC Center for EngineeringModeling and Applied Social SciencesAv.Dos Estados500109210-580Santo AndréSP Brazil Instituto de Pesquisas Energéticas e Nucleares IPEN/CNENAv.Prof.Lineu Prestes2242São PauloBrazil Institute of material Science and Nanotechnology University of La LagunaP.O.Box 456La LagunaTenerife 38200Spain

The study of corrosion of magnesium and its alloys has emerged a hot topic in the applications of lightweight structural materials. The inherently high electrochemical activity of bare magnesium surfaces still lacks a convincing mechanism to describe the observed experimental characteristics, and it has prompted the development of various types of protective coatings with the aim of slowing metal dissolution. In recent years, new instruments and techniques have been developed to study with spatial resolution the local corrosion processes that occur in metallic materials in general, and for magnesium and its alloys in particular, both for bare surfaces and coated. Scanning microelectrochemical techniques, such as local electrochemical impedance spectroscopy(LEIS), scanning electrochemical microscopy(SECm), scanning vibrating electrode technique(SVET), scanning ion-selective electrode technique(SIET) and scanning Kelvin probe(SKP) can provide information about the local electrochemical activity of metallic surfaces. In the present work, the applications of these techniques in corrosion studies of magnesium and its alloys are reviewed. Assessment of corrosion mechanisms, barrier properties of conventional coatings and active corrosion behavior of self-healing coatings are examined. Limitations and future developments in this area are discussed.

关键词： magnesium alloys LEIS SECm SVET SIET SKP

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Litter production and leaf nutrient concentration and remobilization in response to climate seasonality in the central Amazon

引用

Journal of Forestry Research 2024年第3期35卷 131-141页

作者： ricardo Antonio marenco Saul Alfredo Antezana-Vera Daniela Pereira Dias Luiz Antonio Candido Instituto Nacional de Pesquisas da Amazonia Coordenagao de Uso da Terra e Mudanca ClimaticaAv.Andre Araujo 2936ManausAM69067-375Brazil Programa de pos-Graduagao em Agricultura no Tropico Umido Instituto Nacional de Pesquisas da Amazonia-INPAManausAMBrazil Unidade Academica de Ciencias Agrarias Universidade Federal de JataiBR 364km 195JataiGO 75801-615Brazil

Litterfall is the largest source of nutrients to for-est soils of tropical rainforests.However,variability in lit-terfall production,nutrient remobilization,and changes in leaf nutrient concentration with climate seasonality remain largely unknown for the central Amazon.This study meas-ured litterfall production,leaf nutrient remobilization,and leaf area index on a forest plateau in the central Amazon.Litterfall was measured at monthly intervals during 2014,while nitrogen,phosphorus,potassium,calcium and mag-nesium concentrations of leaf litter and canopy leaves were measured in the dry and rainy seasons,and remobilization rates determined.Leaf area index was also recorded in the dry and rainy seasons.monthly litterfall varied from 33.2(in the rainy season)to 87.6 g m^(-2) in the dry season,while leaf area index increased slightly in the rainy season.Climatic seasonality had no effect on concentrations of nitrogen,calcium,and magnesium,whereas phosphorous and potassium responded to rainfall seasonality oppositely.While phosphorous increased,potassium decreased during the dry season.Over seasons,nitrogen,potassium,and phosphorous decreased in leaf litter;calcium increased in leaf litter,while magnesium remained unaffected with leaf aging.Regardless,the five nutrients had similar remobilization rates over the year.The absence of climate seasonality on nutrient remobilization suggests that the current length of the dry season does not alter nutrient remobilization rates but this may change as dry periods become more prolonged in the future due to climate change.

关键词： Throughfall Nutrient cycling Climatic seasonality Leaf mass per area

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Hypothalamic circuits and aging:keeping the circadian clock updated

引用

Neural Regeneration Research 2024年第9期19卷 1919-1928页

作者： Rosa Vázquez-Lizarraga Lucia mendoza-Viveros Carolina Cid-Castro Sareni Ruiz-montoya Erick Carreño-Vázquez ricardo Orozco-Solis Instituto Nacional de medicina Genómica(INmEGEN) México CityMéxico Centro de Investigacíon sobre el Envejecimiento Centro de Investigacíon y de Estudios Avanzados(CIE-CINVESTAV)México CityMéxico Instituto de Investigaciones Biomédicas Universidad Nacional Autónoma de México UNAMMéxico CityMéxico

Over the past century,age-related diseases,such as cancer,type-2 diabetes,obesity,and mental illness,have shown a significant increase,negatively impacting overall quality of life.Studies on aged animal models have unveiled a progressive discoordination at multiple regulatory levels,including transcriptional,translational,and post-translational processes,resulting from cellular stress and circadian derangements.The circadian clock emerges as a key regulator,sustaining physiological homeostasis and promoting healthy aging through timely molecular coordination of pivotal cellular processes,such as stem-cell function,cellular stress responses,and inter-tissue communication,which become disrupted during aging.Given the crucial role of hypothalamic circuits in regulating organismal physiology,metabolic control,sleep homeostasis,and circadian rhythms,and their dependence on these processes,strategies aimed at enhancing hypothalamic and circadian function,including pharmacological and non-pharmacological approaches,offer systemic benefits for healthy aging.Intranasal brain-directed drug administration represents a promising avenue for effectively targeting specific brain regions,like the hypothalamus,while reducing side effects associated with systemic drug delivery,thereby presenting new therapeutic possibilities for diverse age-related conditions.

关键词： aging astrocytes cellular stress responses circadian clock hypothalamus intranasal drug administration metabolic control nutrient sensor SIRT1 sleep homeostasis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Clinicopathological alterations in wild mammals from the reservoir system of Trypanosoma cruzi:a scoping review

引用

Animal Diseases 2024年第1期4卷 48-58页

作者： ricardo Sanchez Pérez Josémanuel Aranda-Coello JoséAntonio De Fuentes Vicente Oscar Rico Chavez Facultad de Estudios Superiores Cuautitlan Universidad Nacional Autonoma deMexicoCuautitlan lzcalliEstadodeMexicoMexico El Colegio de la Frontera Sur-Unidad Campeche CampecheCampecheMexico Instituto de Ciencias Biologicas-Universidad de Ciencias y Artes de Chiapas Tuxtla GutierrezChiapasMexico Facultad de medicina Veterinaria y Zootecnia-Universidad Nacional Autonoma demexico Ciudad deMexicoMexico

Trypanosoma cruzi is the etiologic agent of Chagas disease.This flagellated protozoan is transmitted to humans as well as different species of domestic and wild animals via vectors from the Reduviidae family(known as"kissing bugs").Despite the fact that hundreds of species of wild mammals are part of the reservoir system,the morphologi-cal changes and clinical manifestations resulting from the pathogenesis of the infection have been largely neglected.The aim of this review is to systematically compile the available information regarding clinicopathological altera-tions in wild mammals due to natural infection by T.cruzi.Information was obtained from six online bibliographic data search platforms,resulting in the identification of 29 publications that met the inclusion criteria.mortality was the most common clinical manifestation,cardiac damage was the main finding at necropsy,and lymphoplas-macytic inflammation was the most frequent microscopic injury.Thus,regardless of its role as a reservoir,T.cruzi has the potential to affect the health status of wild mammals,a situation that highlights the need for further research to analyze,measure,and compare its effects at both the individual and population levels.

关键词： Trypanosoma cruzi Chagas disease American trypanosomiasis Clinicopathological alterations Natural infection Wild mammals

来源：

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

morphometry and mineral Content in the Seeds and Soil of Two Species of Argemone L.(Papaveraceae)in the Central Part of the Chihuahuan Desert

引用

Phyton-International Journal of Experimental Botany 2024年第2期93卷 371-386页

作者： Perla Patricia Ochoa-García Jaime Sánchez-Salas ricardo Trejo-Calzada Jesús JosafathQuezada-Rivera Fabián García-González Unidad Regional Universitaria de ZonasÁridas BermejilloUniversidad Autónoma ChapingoDurango35230México Facultad de Ciencias Biológicas Universidad Juárez del Estado de DurangoGómez PalacioDurango35010México

The genus Argemone L.(Papaveraceae)is found widely distributed in mexico’s Chihuahuan Desert(CD).Some species of this genus are of phytochemical or ethnobotanical interest.They are inedible plants considered as scrubs.To date they have not been broadly studied;thus,their ecology is,to our knowledge,unknown.The present work was centered around carrying out a morphometric analysis and the determination of minerals in the soil and seeds of the wild populations of Argemone at sites belonging to two ecoregions of the CD in mexico.In April 2021 and April 2022,seeds of Argemone spp.,and soil samples were collected at 10 sites of the CD.The seeds were selected under a randomized design,and weight,length,diameter,thickness,buoyancy,and mineral content were determined.The soil samples were obtained under the mexican regulation NOm-021-RECNAT-2000,and determinations of mineral content,electrical conductivity,apparent density,and soluble anions were performed.The information obtained was grouped by variable,species,and place of precedence.The statistical tests consisted of an ANOVA,Tukey means tests considering p≤0.05,and a Principal Components Analysis.Argemone pleiacantha exhibited differences in terms of weight(F=54.79,p=0.001),length(F=90.83,p=0.001),thickness(F=104.89,p=0.001),and diameter(F=155.82,p=0.001),and the differences in Argemone mexicana were in weight(F=46.71,p=0.001),thickness(F=187.49,p=0.001),length(F=191.56,p=0.001),and diameter(F=215.83,p=0.001).The evaluated seeds reached their maximal imbibition velocity at 24 h of evaluation.The content of the micro-and macro-nutrients analyzed in the seeds and soil suggest a tight relation with the morphometric characteristics of the seeds.

关键词： micronutrients agricultural area semiarid zone ecoregion buoyancy

来源：

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

Dysregulated microRNAs in type 2 diabetes and breast cancer:Potential associated molecular mechanisms

引用

World Journal of Diabetes 2024年第6期15卷 1187-1198页

作者： Alex Cleber Improta-Caria Filipe Ferrari João Lucas Penteado Gomes Paloma Brasilio Villalta Úrsula Paula RenóSoci ricardo Stein Edilamar m Oliveira Laboratory of Biochemistry and molecular Biology of the Exercise Physical Education and Sport SchoolUniversity of São PauloSão Paulo 05508-030Brazil Graduate Program in Cardiology and Cardiovascular Sciences Federal University of Rio Grande do SulHospital de Clínicas de Porto AlegrePorto Alegre 90035003Brazil Laboratory of metabolic Disorders(Labdime) School of Applied SciencesUniversity of Campinas-UNICAMPCampinas 13484-350Brazil Departments of Internal medicine Molecular Pharmacology and PhysiologyCenter for Regenerative MedicineUSF Health Heart InstituteMorsani College of MedicineUniversity of South FloridaTampaFL 33602United States

Type 2 diabetes(T2D)is a multifaceted and heterogeneous syndrome associated with complications such as hypertension,coronary artery disease,and notably,breast cancer(BC).The connection between T2D and BC is established through processes that involve insulin resistance,inflammation and other factors.Despite this comprehension the specific cellular and molecular mechanisms linking T2D to BC,especially through microRNAs(miRNAs),remain elusive.miRNAs are regulators of gene expression at the post-transcriptional level and have the function of regulating target genes by modulating various signaling pathways and biological processes.However,the signaling pathways and biological processes regulated by miRNAs that are associated with T2D and BC have not yet been elucidated.This review aims to identify dysregulated miRNAs in both T2D and BC,exploring potential signaling pathways and biological processes that collectively contribute to the development of BC.

关键词： Type 2 diabetes Breast cancer microRNAs molecular mechanisms

来源：

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

Effect of Turbidity on Semi-Automatic Analysis of Copepod Size and Abundance Distribution in the Water Column

引用

Advances in Bioscience and Biotechnology 2024年第6期15卷 380-395页

作者： Thiago da Silva matos Carolina Siqueira dos Reis Laura de Andrade moura márcio Abreu ricardo Coutinho Lohengrin Fernandes IEAPm/UFF marine Biotechnology Post-Graduate Program Arraial do Cabo Brazil Instituto de Estudos do mar Almirante Paulo moreira Arraial do Cabo Brazil

Automated image systems to characterize aquatic organisms improve research and enable fast response to environmental risk situations. In November 2015, a dam in mariana City-mG (Brazil) collapsed and led to the disposal of mud tailings from the mining process to the Doce River. The accident resulted in several casualties and incalculable damage to surrounding communities and the environment. The mud increased water turbidity, an essential condition to the functioning of the image analysis systems, and directly affected the characterization of the organisms, making it impossible to distinguish copepods in the mud, due to the blurred outline. To get a quick response evaluating environmental situations, this work aimed to develop and test different algorithms characterizing and classifying copepods by their size (length and area) using in situ images acquired by the Lightframe On-Sight Keyspecies Investigation device. Field tests were carried out under different turbidity levels throughout the gradient observed in the coastal zone adjacent to the Doce River. The best algorithm reduced nearly 50% of the noise in some images when compared with manual treatment and led to 96% accuracy in measurement and counting. Semi-automated devices that perform post-processing corrections are suitable for fast environmental evaluation under high turbidity scenarios.

关键词： Imaging Zooplankton Doce River LOKI Copepod

来源：

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

Distribution and Relation of Primes with Tesla Numbers 3, 6, and 9

引用

Journal of Applied mathematics and Physics 2024年第4期12卷 1021-1027页

作者： Javier mendoza-Navarrete Huetzin Perez Ismael Ojeda Victor Verdugo Gabriel Luna Sandoval ricardo Jimenez Garcia Jaime Alvarez Departametno de matemá ticas CBTis 256 DGETI Cabo San Lucas M&#233xico DCI Departamento de Fisica mé dica Universidad de Guanajuato Leon M&#233xico Divisió n de Ingenieria en Sistemas Computacionales Tecnol&#243gico Nacional de M&#233xico ITES Los Cabos Cabo San Lucas M&#233xico Departamento de Ingenieria Industrial en manufactura Universidad Estatal de Sonora Navojoa M&#233xico Departamento de Elé ctrica-Electr&#243nica Tecnol&#243gico Nacional de M&#233xico Campus Mexicali Mexicali M&#233xico Guanajuato M&#233xico

This work presents a different approach to twin primes, an approach from the perspective of the Tesla numbers and gives a refresh and new observation of twin primes that could lead us to an answer to the Twin Prime Conjecture problem. We expose a peculiar relation between twin primes and the generation of prime numbers with Tesla numbers. Tesla numbers seem to be present in so many domains like time, vibration and frequency [1], and the space between twin primes is not the exception. Let us say that twin primes are more than just prime numbers plus 2 or minus 2, and Tesla numbers are more involved with twin primes than we think, and hopefully, this approach give us a better understanding of the distribution of the twin pairs.

关键词： Tesla Numbers Prime Number Twin Prime Numbers Twin Pair

来源：

维普期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Extrahepatic cholestasis associated with paracoccidioidomycosis:Challenges in the differential diagnosis of biliopancreatic neoplasia

引用

World Journal of Gastrointestinal Oncology 2024年第6期16卷 2531-2540页

作者： Jose Sebastiao dos Santos Vitor de moura Arrais William Jose Rosseto Ferreira ricardo Ribeiro Correa Filho mariangela Ottoboni Brunaldi Rafael Kemp Ajith Kumar Sankanrakutty Jorge Elias Junior Fernando Bellissimo-Rodrigues Roberto martinez Edson Zangiacomi martinez Jose Celso Ardengh Faculdade de medicina de Ribeirao Preto da Universidade de Sao Paulo(FmRP-USP) Departamento de Cirurgia e AnatomiaRibeirao Preto 14049-900Sao PauloBrazil Universidade de Sao Paulo Faculdade de Medicina de Ribeirao Preto da Universidade de Sao Paulo(FMRP-USP)Departamento de PatologiaRibeirao Preto 14048900Sao PauloBrazil Universidade de Sao Paulo Faculdade de Medicina de Ribeirao Preto da Universidade de Sao Paulo(FMRP-USP)Departamento de Imagens MédicasHematologia e Oncologia ClínicaRibeirao Preto 14048900Sao PauloBrazil Universidade de Sao Paulo Faculdade de Medicina de Ribeirao Preto da Universidade de Sao Paulo(FMRP-USP)Departamento de Medicina SocialRibeirao Preto 14015-010Sao PauloBrazil Universidade de Sao Paulo Faculdade de Medicina de Ribeirao Preto da Universidade de Sao Paulo(FMRP-USP)Departamento de Clínica MédicaRibeirao Preto 14015-010Sao PauloBrazil Universidade de Sao Paulo Faculdade de Medicina de Ribeirao Preto da Universidade de Sao Paulo(FMRP-USP)Departamento de Cirurgia e AnatomiaRibeirao Preto 14049-900Sao PauloBrazil and Hospital MoriahServico de Endoscopia DigestivaSao Paulo 04084-002Sao PauloBrazil

BACKGROUND Paracoccidioidomycosis(PCm)may involve the hepatic pedicle and peripan creatic lymph nodes,cause damage to the bile duct and manifest,exceptionally,in combination with extrahepatic cholestasis(EHC),making investigation and treatment challenging.AIm To investigate the management of patients with visceral PCm admitted with EHC.mETHODS All patients diagnosed with PCm treated in a public,tertiary teaching hospital between 1982 and 2020 were retrospectively evaluated.Those also identified with EHC were allocated to two groups according to the treatment approach for the purpose of comparing clinical,laboratory,and imaging findings,resources used for etiological diagnosis,treatment results,and prognosis.Statistical analyses were performed using the linear mixed-effects model(random and fixed effects),which was adjusted using the PROC mIXED procedure of the SAS®9.0 software,and Fisher’s exact test.RESULTS Of 1645 patients diagnosed with PCm,40(2.4%)had EHC.Of these,20(50.0%)lived in the rural area and 29(72.5%)were men,with a mean age of 27.1 years(3-65 years).Jaundice as first symptom and weight loss of at least 10 kg were observed in 16 patients(40.0%),and a mass in the head of the pancreas was observed in 8(20.0%).The etiological diagnosis was made by tissue collection during surgery in 4 cases(10.0%)and by endoscopic methods in 3 cases(7.5%).Twenty-seven patients(67.5%)received drug treatment alone(Group 1),whereas 13(32.5%)underwent endoscopic and/or surgical procedures in combination with drug treatment(Group 2).EHC was significantly reduced in both groups(40.7% in Group 1,with a mean time of 3 months;and 38.4% in Group 2,with a mean time of 7.5 months),with no statistically significant difference between them.EHC recurrence rates,associated mainly with treatment nonadherence,were similar in both groups:37% in Group 1 and 15.4% in Group 2.The mortality rate was 18.5% in Group 1 and 23% in Group 2,with survival estimates of 71.3% and 72.5%,respectively,with no statistically significant difference.CONCLUSI

关键词： Cholestasis Jaundice Obstructive Blastomycosis Paracoccidioides Diagnosis Treatment

来源：

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

The Nikola Tesla Constant and Its Relation to the Circumference Inscribed in a Square

引用

Journal of Applied mathematics and Physics 2024年第1期12卷 277-283页

作者： Javier mendoza Navarrete José Ismael Ojeda Campaña Huetzin Perez Gabriel Luna-Sandoval Victor Verdugo ricardo Jiménez Garcia Departamento de matemáticas CBTis 256 DGETI Cabo San Lucas México División de Ingeniería en Sistemas Computacionales Tecnológico Nacional de México/ITES de Los Cabos Cabo San Lucas México DCI Departamento de Física médica Universidad de Guanajuato León México Departamento de Ingeniería Industrial en manufactura Universidad Estatal de Sonora Navojoa México Departamento de Eléctrica-Electrónica Tecnológico Nacional de México Campus Mexicali Mexicali México

This research work relates the surface of a square and the area circumscribed by a circle, resulting in a value called Nikola Tesla constant. This constant starts with the calculation of the areas of the square and the inscribed circle, giving a ratio of 9/40 and from which a residual area of the area proportions of the geometric figures described is obtained. Plotting smooth curves, particularly those in round shapes, can be represented efficiently with the use of Nikola Tesla constant, reducing complex mathematical calculus.

关键词： Tesla Numbers Prime Number Circle Binary Area

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：