检索结果-南通市图书馆

Rotating effects on the photoionization cross-section of a 2D quantum ring

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2024年第10期76卷 153-159页

作者： Carlos Magno O Pereira Frankbelson dos s Azevedo luís Fernando C Pereira Edilberto O silva Departamento de Física Universidade Federal do Maranh?o

In this article, we investigate the nonrelativistic quantum motion of a charged particle within a rotating frame, taking into account the Aharonov–Bohm(AB) effect and a uniform magnetic field. Our analysis entails the derivation of the equation of motion and the corresponding radial equation to describe the system. solving the resulting radial equation enables us to determine the eigenvalues and eigenfunctions, providing a clear expression for the energy levels. Furthermore,our numerical analysis highlights the substantial influence of rotation on both energy levels and optical properties. specifically, we evaluate the photoionization cross-section with and without the effects of rotation. To elucidate the impact of rotation on the photoionization process of the system, we present graphics that offer an appealing visualization of the intrinsic nature of the physics involved.

关键词： Aharonov-Bohm effect photoionization cross-section quantum ring rotating effect

Influence of previous plane of nutrition on molecular mechanisms regulating the expression of urea and water metabolism related genes in the rumen and kidney of finishing crossbred Angus steers

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Animal Nutrition 2024年第2期17卷 232-243页

作者： Aghata E.Moreira da silva Arturo Macias Franco Bradley s.Ferguson Mozart A.Fonseca College of Agriculture Biotechnology&Natural Resources University of Nevada Department of Animal and Range sciences Clayton Livestock Research Center New Mexico State University

This study aimed to understand how molecular mechanisms controlling water and urea metabolism at the finishing phase can be affected by previous plane of nutrition of crossbred Angus beef steers. Twentyfour(n = 24) animals were randomly distributed into either a moderate(MP) or high plane of nutrition during the background phase for 85 d. Animals were then blocked by their previous plane and were moved onto a 105-d finishing phase in a 2 × 2 factorial arrangement. The forage-finished group received only high-quality alfalfa hay, whereas the grain-fed group received a high grain diet(80% whole corn and20% alfalfa hay). By the end of the finishing phase, animals were harvested and tissue samples from the rumen and kidney were collected. Changes in gene expression of aquaporins(AQP)-2,-3,-4,-7, ATP1A1,ATP1B1, sGK1, CLIC1(kidney and rumen), UT-A1(kidney only) and UT-B(rumen only), were assayed via real-time q PCR; 18s r RNA was used as an endogenous control. One-way ANOVA followed by Tukey's post hoc analysis was conducted. When animals were from MP, forage-finishing increased the relative abundance of AQP3(P ≤ 0.05), AQP7(P ≤ 0.05), ATP1B1(P ≤ 0.05), and sGK1(P ≤ 0.05) in the kidney when compared to grain-fed animals. In the rumen, for the MP group, AQP7 was differentially expressed in both treatments at the finishing phase(P ≤ 0.01), with forage-finished steers having the highest expression of AQP7. For the MP group, UT-B had a tendency of presenting a higher expression on grainfed animals(P = 0.075). Overall, these results suggest that previous plane can impact expression of genes associated with water and urea metabolism during the finishing phase, namely AQP3, AQP7, ATP1B1, and sGK1 in the kidney, and AQP7 and UT-B in the rumen. The greatest impact observed on gene expression changes of investigated genes at the finishing phase was reflective of animals backgrounded on the moderate previous plane.

关键词： Gene expression Aquaporin sodium channel Urea transporter

Molecular and cellular mechanisms of neuroprotection by oligopeptides from snake venoms

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

BIOCELL 2024年第6期48卷 897-904页

作者： CARLOs ALBERTO-silva BRENda RUFINO da silva Natural and Humanities sciences Center Experimental Morphophysiology LaboratoryFederal University of ABC(UFABC)São Bernardo do CampoSão PauloBrazil

Venom snake-derived peptides have multiple biochemical,pharmacological,and toxicological proﬁles,allowing for the discovery of new medicinal products and therapeutic *** review speciﬁcally examines the fundamental elements of neuroprotection offered by different oligopeptides derived from snake *** also includes a brief evaluation of short peptides that are being considered as potential therapeutic ***-rich peptides and tryptophyllin family peptides isolated from the crude venom of Viperidae family snakes,speciﬁcally Bothrops atrox,Bothrops jararaca,and Bothrops moojeni,have been shown to have pro-survival properties,the ability to reduce oxidative stress,and the ability to promote cell viability and mitochondrial *** signiﬁcant mechanisms are related to the neuroprotection mediated by snake venom oligopeptides:(1)Activation of the L-arginine metabolite pathway,such as polyamines from ornithine metabolism,which reduces N-methyl-D-aspartate(NMda)-type glutamate receptor activity;(2)Enhancement of cell viability by activating the nerve growth factor-signaling pathway;and(3)Activation of the Muscarinic acetylcholine receptor subtype M1(mAChR-M1).These small peptides show promise as neuroprotective agents against a variety of neurodegenerative disorders.

关键词： Neuroprotective peptides Neurodegenerative disease Oxidative stress Reactive oxygen species Biopeptides

Impact Containment Barriers with Geotextile Tubes

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 Geoscience and Environment Protection 2024年第5期12卷 325-344页

作者： Flávio da silva Ornelas luís Fernando Martins Ribeiro Rafael Cerqueira silva Instituto Federal de Educaç &#227o Ci&#234ncia e Tecnologia&#8212IFTO Palmas Brasil Departamento de Engenharia Civil e Ambiental Programa de p&#243s gradua&#231&#227o em Geotecnia Universidade de Bras&#237lia&#8212UnB/Campus Universit&#225rio Darcy Ribeiro Bras&#237lia Brasil

Recently, tragic tailings.dam collapses in Brazil have caused deaths and major destruction and the need to develop technologies capable of preventing damage to people and the environment. Brazilian tailings.dams are in a situation of uncertainty due to new legislation that even requires decommissioning, an activity that involves many problems and where the risk of failure is the main one. An impact containment structure downstream of these dams can be effective and geotextile tubes, in a new approach, have emerged as an option with advantages in terms of execution, costs and safety. The technology is versatile and can bring many benefits such as the reuse of tailings or filling with low-energy or reused materials. In this research, geotextile tubes were tested as free containment barriers, experiencing impacts in reduced models. The safety factor for the stability of the structure was constructed using an equation which is the ratio between the self-weight of the barrier structure and its coefficient of static friction and the impact pressure, where the data showed an adequate correlation which suggests the viability of mitigating risks.

关键词： Geotextile Tube Debris Flow Barriers Impact Mining

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

Assembly structures of coastal woody species of eastern south America:Patterns and drivers

在线全文

学校读者我要写书评

暂无评论

Plant Diversity 2024年第5期46卷 611-620页

作者： Eduardo Vinícius.da silva Oliveira Myrna Friederichs Landim sidney F.Gouveia Graduate Program in Ecology and Conservation Federal University of SergipeSão CristovãoSergipeBrazil National Institute of science and Technology Ecology Evolution and Conservation of Biodiversity(INCT-EECBio)GoiâniaGoiasBrazil Department of Biology Federal University of SergipeSão CristóvãoSergipeBrazil Department of Ecology Federal University of SergipeSão CristóvãoSergipeBrazil

Tropical regions have provided new insights into how ecological communities are *** dry coastal communities,water stress has been hypothesized to determine plant assembly structure by favoring preadapted lineages from neighboring ecosystems,consistent with functional ***,it is unclear whether this hypothesis is sufficient to explain how coastal communities in tropical ecosystems are ***,we test whether water stress or other factors drive community assembly in woody plant communities across the coastal zone of Brazil,a tropical *** characterized functional and phylogenetic structures of these communities and determined the underlying environmental factors(e.g.,water stress,historical climate stability,edaphic constraints,and habitat heterogeneity)that drive their community *** of coastal woody species show geographically varied patterns,including stochastic arrangements,clustering,and overdispersion of species relative to their traits and phylogenetic *** complexity,water vapor pressure,and soil nutrient availability best explained the gradient in the functional *** deficit,water vapor pressure,and soil organic carbon were the best predictors of variation in phylogenetic *** results support the water-stress conservatism hypothesis on functional and phylogenetic structure,as well as the effect of habitat heterogeneity on functional structure and edaphic constraints on functional and phylogenetic *** effects are associated with increased phenotypic and phylogenetic divergence of woody plant assemblages,which is likely mediated by abiotic filtering and niche opportunities,suggesting a complex pattern of ecological assembly.

关键词： Brazil Completeness Clustering Restinga vegetation Water constraints

How far have we come?Review of main public policies to reduce landslide impacts in Brazil

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain science 2024年第9期21卷 2891-2904页

作者： Bianca Carvalho VIEIRA Tiago damas MARTINs Telma Mendes.da silva JoséEduardo BONINI Department of Geography University of São PauloAvenida Professor Lineu Prestes 05508-000Brazil Cities Institute Federal University of São PauloAvenida Jacu-Pêssego 08260-001Brazil Department of Geography Federal University of Rio de JaneiroAvenida Athos da Silveira Ramos 21941-916Brazil

During the rainy season in Brazil,landslides can have catastrophic consequences,including loss of life,damage to urban infrastructure and significant economic ***,more than eight million people in Brazil live in disaster-prone *** objective of this article is to present a chronological review of the principal policies and programmes at the national,state,and municipal levels,with an emphasis on their key actions aimed at mitigating the impact of disasters related to natural hazards,particularly *** analysis was based on official records of public policies from the national,state,and municipal *** results show that several initiatives were initially developed at the local and regional ***,it was not until the late 1980s that a comprehensive organisation of civil protection at the national level emerged as a response *** is possible to highlight three phases(understanding,coexistence,and prevention)of institutional action focused on risk management in the face of *** the growing knowledge of risk scenarios,disasters continue to occur in Brazil on an annual basis,revealing several obstacles to reducing their impact,particularly given the social and economic disparities between Brazilian regions and the applicability of public policies that must overcome the limitations of each municipality.

关键词： Disasters Risk Mitigation Prevention Legislation Civil Defense Natural Hazards

Perianal disease in inflammatory bowel disease:Broadening treatment and surveillance strategies for anal cancer

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第28期30卷 3373-3385页

作者： Tatiana Pacheco sara Monteiro luísa Barros Jorge silva Department of Gastroenterology Centro Hospitalar do Tamega e SousaPenafiel 4560-136Portugal

The perianal disease affects up to one-third of individuals with Crohn's disease(CD),causing disabling symptoms and significant impairment in quality of life,particularly for those with perianal fistulising CD(PFCD).The collaborative effort between gastroenterologists and surgeons is essential for addressing PFCD to achieve fistula closure and promote luminal *** fistula healing rates with conventional therapies have prompted the emergence of new biological agents,endoscopic procedures and surgical techniques that show promising *** these,mesenchymal stem cells injection is a particularly hopeful *** addition to the burden of fistulas,individuals with perianal CD may face an increased risk of developing anal *** underscores the importance of surveillance programmes and timely interventions to prevent late diagnoses and poor ***,there is no established formal anal screening *** this review,we provide an overview of the current state of the art in managing PFCD,including novel medical,endoscopic and surgical *** discussion also focuses on the relevance of establishing an anal cancer screening programme in CD,intending to propose a risk-based surveillance *** validation of this surveillance programme would be a significant step forward in improving patient care and outcomes.

关键词： Inflammatory bowel disease Crohn's disease Perianal Fistula Anus diseases Management Anal cancer screening

supercritical fluid technology as a sustainable alternative method for textile dyeing:An approach on waste,energy,and CO_(2)emission reduction

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 Environmental sciences 2024年第6期140卷 123-145页

作者： Carlos Rafael silva de Oliveira Patrícia Viera de Oliveira Leandro Pellenz Catia Rosana Lange de Aguiar Afonso Henrique da silva Júnior Federal University of santa Catarina Textile Engineering Department2514 João Pessoa St.BlumenauSC89036-004Brazil Federal University of santa Catarina Chemical Engineering DepartmentS/n Biotério Central St.FlorianópolisSC88040-900Brazil

The clothing industry is considered one of the most polluting industries on the planet due to the high consumption of water,energy,chemicals/dyes,and high generation of solid waste and *** with environmental concerns,the textile ennoblement sector is the most critical of the textile production chain,especially the traditional dyeing *** an alternative to current problems,dyeing with supercritical CO_(2)(scCO_(2))has been presented as a clean and efficient process for a sustainable textile *** fluid dyeing(sFD)has shown a growing interest due to its significant impact on environmental preservation and social,economic,and financial *** main sFD benefits include economy and reuse of non-adsorbed dyes;reduction of process time and energy expenditure;capture of atmospheric CO_(2)(greenhouse gas);use and recycling of CO_(2)in sFD;generation of carbon credits;water-free process;effluent-free process;reduction of CO_(2)emission and auxiliary *** being still a non-scalable and evolving technology,sFD is the future of *** review presented a comprehensive overview of the environmental impacts caused by traditional processes and confronted the advantages of *** sFD technique was introduced,along with its latest advances and future *** and environmental gains were also discussed.

关键词： Textile industry supercritical dyeing sustainable processes Water free dyeing Energy saving Cleaner production