检索结果-南通市图书馆

High Order of Accuracy for Poisson Equation Obtained by Grouping of Repeated Richardson Extrapolation with Fourth Order Schemes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2021年第8期128卷 699-715页

作者： Luciano pereira da silva Bruno Benato Rutyna aline Roberta Santos Righi Marcio Augusto Villela Pinto Graduate Program in Numerical Methods in Engineering Federal University of ParanaCuritiba81531-980Brazil Graduate Program in Space Sciences and Technologies Aeronautics Institute of TechnologySao Jose dos Campos12228-900Brazil Department of Mechanical Engineering Federal University of ParanaCuritiba81531-980Brazil

In this article,we improve the order of precision of the two-dimensional Poisson equation by combining extrapolation techniques with high order *** high order solutions obtained traditionally generate non-sparse matrices and the calculation time is very *** can obtain sparse matrices by applying compact *** this article,we compare compact and exponential finite difference schemes of fourth *** numerical solutions are calculated in quadruple precision(Real*16 or extended precision)in FORTRAN language,and iteratively obtained until reaching the round-off error magnitude around 1.0E−*** procedure is performed to ensure that there is no iteration *** Repeated Richardson Extrapolation(RRE)method combines numerical solutions in different grids,determining higher orders of *** main contribution of this work is based on a process that initializes with fourth order solutions combining with RRE in order to find solutions of sixth,eighth,and tenth order of *** multigrid Full Approximation Scheme(FAS)is also applied to accelerate the convergence and obtain the numerical solutions on the fine grids.

关键词： Tenth order accuracy RRE compact scheme exponential scheme multigrid finite difference

Energetic-protein supplementation in the last 60 days of gestation improves performance of beef cows grazing tropical pastures

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 Animal Science and Biotechnology 2018年第1期9卷 208-216页

作者： aline Gomes da silva Mário Fonseca Paulino Edenio Detmann Henrique Jorge Fernandes Lincoln da silva Amorim Román Enrique Maza Ortega Victor Valério de Carvalho Josilaine aparecida da Costa Lima Felipe Henrique de Moura Mariana Benevides Monteiro Jéssika Almeida Bitencourt Universidade Federal de Vicosa VicosaMinas Gerais 36570-000Brazil Universidade Federal de Mato Grosso do Sul Campo GrandeMato Grosso do Sul 79074-460Brazil Universidade Estadual de Mato Grosso do Sul AquidauanaMato Grosso do Sul 79200-000Brazil Biotran Biotecnologia e Treinamento em Reproducao Animal AlfenasMinas Gerais 37130-000Brazil Universidade Federal do Acre Rio BrancoAcre 69920-900Brazil

Background： Nutrition is one of the most important factors that affect animal performance, and it therefore also impacts on financial results in beef systems. In this way, finding the best strategy for feeding supplements is of paramount importance. Aiming to evaluate the effect of supplement feeding strategies for beef cows in the last third of gestation, two experiments were conducted. In Experiment 1, 35 pregnant Nellore cows were assigned to a completely randomized design with four treatments： control, which received no supplement; supplementation for the last 30 d of gestation（30-d; 3.0 kg/d）; supplementation for the last 60 d of gestation（60-d; 1.5 kg/d）; or supplementation for the last 90 d of gestation（90-d; 1.0 kg/d）. All supplemented treatments received the same total amount of supplement throughout the experiment： 90 kg（20% of crude protein）. A second experiment（Experiment 2） was delineated to evaluate the effects of the amounts offered in Experiment 1 on intake and metabolism. Four multiparous pregnant Nellore cows were assigned to a 4 × 4 Latin square design, with periods of15 d ***： There was a linear effect of the number of days of supplementation on calving body weight（BW; P 〈 0.05）and a quadratic effect on BW change from parturition to d 31 post-calving（P 〈 0.05）, with cows on the 60-d strategy losing less BW post-calving. No difference was found in offspring birth BW（P 〉 0.10）. A significant linear effect on interval from parturition to conception（P 〈 0.05） was observed, with the highest calving to conception interval being observed in the 90-d strategy. The level of supplementation did not affect forage intake or neutral detergent fiber digestibility（P 〉 0.10）. Nitrogen excreted through urine tended to increase linearly with the level of supplementation（P 〈 0.10）.Conclusion： Providing 1.5 kg of supplement during the last 60 d of gestation improves cow performance after calving, reducing the magnitude of BW lost, and reduces the number of

关键词： Flushing Nutrition Parturition Reproduction

Pathogenesis and clinical management of Helicobacter pylori gastric infection

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

World Journal of Gastroenterology 2019年第37期25卷 5578-5589页

作者： Breno Bittencourt de Brito Filipe Ant?nio Fran?a da silva aline silva Soares Vinícius Afonso pereira Maria Luísa Cordeiro Santos Mariana Miranda Sampaio Pedro Henrique Moreira Neves Fabrício Freire de Melo Instituto Multidisciplinar em Saúde Universidade Federal da Bahia

Helicobacter pylori(***)is a gram-negative bacterium that infects approximately 4.4 billion individuals ***,its prevalence varies among different geographic areas,and is influenced by several *** infection can be acquired by means of oral-oral or fecal-oral transmission,and the pathogen possesses various mechanisms that improve its capacity of mobility,adherence and manipulation of the gastric microenvironment,making possible the colonization of an organ with a highly acidic *** addition,*** presents a large variety of virulence factors that improve its pathogenicity,of which we highlight cytotoxin associated antigen A,vacuolating cytotoxin,duodenal ulcer promoting gene A protein,outer inflammatory protein and gamma-glutamyl *** host immune system,mainly by means of a Th1-polarized response,also plays a crucial role in the infection *** most ***-positive individuals remain asymptomatic,the infection predisposes the development of various clinical conditions as peptic ulcers,gastric adenocarcinomas and mucosa-associated lymphoid tissue *** and non-invasive diagnostic methods,each of them with their related advantages and limitations,have been applied in *** ***,bacterial resistance to antimicrobial therapy is a major challenge in the treatment of this infection,and new therapy alternatives are being tested to improve *** *** but not least,the development of effective vaccines against *** infection have been the aim of several research studies.

关键词： Helicobacter pylori Virulence factors Immune response Antibiotics Vaccines

Chlorophyll Fluorescence as an Indicator of Cellular Damage by Glyphosate Herbicide in Raphanus sativus ***

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

American Journal of Plant Sciences 2014年第16期5卷 2509-2519页

作者： Fabia Barbosa silva Alan Carlos Costa Rodolfo Rodrigo pereira Alves Clarice aparecida Megguer Instituto Federal de Educacao Ciencia e Tecnologia—Campus Rio VerdeRio VerdeBrazil

The fodder radish is an important alternative late summer crop in central-western Brazil. The fodder radish has a short growing cycle, is highly productive and possesses qualities that enhance its cultivation potential as an alternative in Brazil’s Biodiesel Program. However, drift of herbicides, such as glyphosate, may hinder the development of fodder radishes. Studies of chlorophyll fluorescence can provide measurements that help assess the effect of herbicide, being good indicator of the damage to photosynthetic apparatus promoted by herbicide. This study was carried out to analyze the effects of glyphosate by measuring chlorophyll a fluorescence, cellular membrane stability and chloroplast pigment contents in fodder radish plants. This experiment used a randomized block design in which the treatments consisted of the following 6 different doses: control, 0, 150, 300, 450, 600, 750 and 900 g i.a. ha-1 of the recommended 480 g·L-1 dose of glyphosate acid equivalent. The plants were sprayed 30 days after emergence and were assessed every 48 hours. The characteristics evaluated, including chlorophyll a fluorescence, chloroplast pigments and the rate of electrolyte leakage, indicated that radish plants are sensitive to glyphosate because the treatments resulted in reduced levels of photosynthetic efficiency and increased damage to cellular membranes, which led to a reduction in the chloroplast pigment content.

关键词： Pigments Chloroplastidic EPSPS Chlorophyll Fluorescence

A single administration of fish oil inhibits the acute inflammatory response in rats

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2017年第8期10卷 830-837页

作者： Laura Licia Milani de Arruda Franciele Queiroz Ames Damila Rodrigues de Morais Renata Grespan Ana Paula Maziero Gil Maria Angelica Raffaini Covas pereira silva Jesui Vergilio Visentainer Roberto Kenji Nakamura Cuman Ciomar aparecida Bersani-Amado Department of Pharmacology and Therapeutics State University of MaringaMaringa-PRBrazil Department of Chemistry State University of MaringaMaringa-PRBrazil

Objective: To investigate the antiinflammatory effects of a single administration of fish oil(FO) on the acute inflammatory response. Methods: The paw edema and pleurisy models were used to evaluate the effects of FO dissolved in olive oil(FOP) orally administered in a single dose in rats. Nitric oxide(NO) concentrations in the pleural exudate were performed according to the Griess method and the cytokine concentrations were determined by Luminex bead-based multiplex assay. Results: FOP treatment(30 and 300 mg/kg) significantly reduced paw edema. FOP treatment at 18.75, 37.5, 75.0, 150.0, and 300 mg/kg decreased both the volume of pleural exudate and cellular migration into the pleural cavity and each of these doses presented the same effectiveness. Treatment with FOP(300 mg/kg) reduced NO, TNF-α, IL-1β, and IL-6 concentrations in the pleural exudate. Conclusions: The present data provide evidence that FO has inhibitory effects on the acute inflammatory response when administered in a single dose in rats. This effect might be attributable to a direct inhibitory effect of FO on the production or release of inflammatory mediators that are involved in the pathological processes evaluated herein.

关键词： Omega-3 fatty acid Polyunsaturated fatty acid Pleurisy Leukocyte migration EPA DHA

Production of Peanut Intercropped with Forage Palm in Pernambuco State, Brazil

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

American Journal of Plant Sciences 2015年第6期6卷 818-825页

作者： Juliana aparecida Santos Andrade Jeandson silva Viana José Jairo Florentino Cordeiro Junior Abraao Cicero da silva Edilma pereira Goncalves Djayran Sobral Costa Academic Unit Garanhuns Federal Rural University of PernambucoRecifeBrazil

The greater use of crop fields by increasing plant population is an alternative to minimize losses to the farmers who use crop intercropped provides other benefits such as lower incidence of diseases and pests, and better exploitation and enrichment agroecosystem. The objective of this study was to evaluate the effect of the population of peanuts with and without inoculation and intercropping with forage palm on growth, productivity and biomass peanut. The treatments consisted of different populations of peanut (one, two and three rows of peanut row spacing of two meters of cactus pear), with and without inoculant, analyzed in subdivided plot scheme (3 × 2), totalizing six treatments in a randomized block design with four replications. The variables evaluated were plant height, number of branches, shoot dry mass and root nodule number, nodule dry weight, biomass productivity and legumes. The largest population of plants in number of lines of peanut intercropped with forage cactus promotes greater total biomass production and yield of beans and does not alter the height, branch number, dry mass of aerial part roots and nodules. The inoculant application did not result in to increased productivity biomass and growth of peanut plants, their use is not indicated. The planting of a row of peanuts between the rows of palm is not economically recommended.

关键词： Arachis hypogaea L. Inoculation Population Nopalea cochenillifera

Polyphenolic composition, antibacterial, modulator and neuroprotective activity of Tarenaya spinosa(Jacq.) Raf.(Cleomaceae)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Biomedicine 2019年第1期9卷 12-17页

作者： Francisca Samara Muniz dos Santos Jose Weverton Almeida Bezerra Jean Paul Kamdem aline Augusti Boligon Marli Matiko Anraku Ana Raquel pereira da silva Kleber Ribeiro Fidelis Nadghia Figueiredo Leite Antonio Ivanildo Pinho Henrique Douglas Melo Coutinho Jose Edilson Goncalves dos Santos Microscopy Laboratory Regional University of Cariri (URCA) Program Post graduate in Plant Biology (UFPE) Phytochemical Laboratory Department of Industrial Pharmacy Federal University of Santa Maria (UFSM) Microbiology and Molecular Biology Laboratory Regional University of Cariri (URCA)

Objective: To evaluate the antibacterial activity and neuroprotective capacity of the ethanolic and aqueous extracts of Tarenaya spinosa(T. spinosa) as well as to determine and quantify some of its polyphenols by high performance liquid chromatography with diode-array detection(HPLC-DAD). Methods: The bacterial Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa strains, grown in Heart Agar Infusion, were tested. The drugs gentamicin, norfloxacin and imipenem were used to evaluate the modulating or antagonistic capacity of the T. spinosa extracts. The extract was analysed by HPLC-DAD to determine the main phenolic compounds. For the cell viability tests, individual heads of the Nauphoeta cinerea arthropod model were removed, homogenized in Trifluoromethyl ketone and centrifuged afterwards. Subsequently, 20 μL of NaN O2 were added to the biological material, except in the control group, to evaluate the protection capacity of the extracts. The homogenate of the insect heads was incubated for 2 h in tubes containing tetrazolium bromide. Results: HPLC-DAD demonstrated that the ethanolic extract of T. spinosa presented caffeic acid as the major compound. The ethanolic extract also showed neuroprotective effects at concentrations ≥ 10 μg/mL, while aqueous extract was shown to have a protective effect only at the concentration of 100 μg/mL. The aqueous extract demonstrated a clinically relevant antibacterial activity against the Staphylococcus aureus multidrug resistant strain-MDR, with MIC 512 μg/m L. However, when the extracts were associated with gentamicin and imipenem, a synergism was detected against Staphylococcus aureus and Escherichia coli MDR strains. Conclusions: Although it does not present an antibacterial action, the extracts of T. spinosa can be used in the pharmaceutical industries since its extracts show modulating action of drugs. Besides, these natural products have neuroprotective capacity.

关键词： Tarenaya spinosa Cleome spinose Nauphoeta cinerea Synergism Antibiotic resistance

Assessment of the Integrity and Retention of Chromium (VI) in Portland Cement Pastes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Chemical Engineering and Science 2021年第1期11卷 1-17页

作者： Ferreira Raul Tadeu Lobato Fortaleza Dário Batista Amorim Kelly aparecida da Encarnação Lira Fernanda silva silva Marizete Helena pereira Wagner Batista Santos Institute of Exact Sciences and Earth Federal University of Mato Grosso Barra do Gar&#231as/MT Brazil

Chromium is a heavy metal used for various applications such as in the manufacture of stainless steels, in chemicals for wood treatment, in tanneries, and in the refractory industry. The main problem associated with the use of chromium in these activities is the considerable volume of contaminated effluent that requires treatment, mainly due to its high mobility and toxicity in its hexavalent form. Immobilization methods arise as an efficient solution for the treatment of these wastes through converting them into inert and stable materials. The present paper aims to investigate Portland cement II’s paste properties with potassium dichromate addition in order to verify the chromium immobilization process. Analyses of moisture content, water absorption, axial compressive strength, and solubilization were done in samples at 7 and 28 days with 0%;0.5%;1.05;1.5%;2.0% and 2.5% potassium dichromate addition. The results showed the influence of this salt in cement hydration reactions, damaging the mechanical behavior and the water absorption capability of the material produced. In the solubilization test, all compositions had >99% efficiency of chromium immobilization in both ages of hydration, thus demonstrating the capability of a cementitious matrix to stabilize this metal.

关键词： Wastes Solidification-Stabilization Chromium Solubilization

Carcass image segmentation using CNN-based methods

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Information Processing in Agriculture 2021年第4期8卷 560-572页

作者： Diogo Nunes Goncalves Vanessa aparecida de Moares Weber Julia Gindri Bragato Pistori Rodrigo da Costa Gomes Anderson Vicoso de Araujo Marcelo Fontes pereira Wesley Nunes Goncalves Hemerson Pistori Federal University of Mato Grosso do Sul Av.Costa e Silvas/nBairro UniversitarioCampo GrandeMS 79070-900Brazil INOVISAO Dom Bosco Catholic UniversityAvenida Tamandare6000CP 100Jardim SeminarioCampo GrandeMS 79117-900Brazil EMBRAPA Gado de Corte Av.Radio Maia830Vila PopularCampo GrandeMS 79106-550Brazil State University of Mato Grosso do Sul Av.Dom Antonio Barbosa4155Vila Santo AmaroCampo GrandeMS 79115-898Brazil

Carcass grading can be used as an important metric to determine meat ***,carcass grading is usually performed by a specialist,making it a subjective and errorprone *** increase the accuracy of such task,image-based systems have been proposed in the *** of the most important parts of an image-based system is the image segmentation,which aims to identify the regions of the carcass in the *** this paper,we propose the use of two recent image segmentation methods called Superpixel+CNN(Convolutional Neural Network)and *** evaluate both methods,we have also built a dataset of carcass images and their *** of approximately 96%of pixel accuracy show the robustness of the methods in carcass image *** novelty of this work is the proposal and comparison of recent deep learning methods that use CNN and superpixels in carcass *** this way,the methods can be used in carcass grading systems to increase the accuracy of the grading task.

关键词： Carcass grading Image segmentation Convolutional neural networks Superpixels