7,520 research outputs found
Cost and efficiency analysis of commercial softeners in the sewability behavior of cotton fabrics
This paper reports a comparative case study on the use of different softening products for bed linen fabrics, specifically regarding the sewability of the fabrics. The market offers a wide variety of commercial formulations of softeners for this purpose, but the composition and price varies considerably. This work was aimed to assess the relationship between the cost and effectiveness of different softener formulations in home textiles finishing. Objectively, the effect of different softeners and their concentrations on sewability of the fabrics was studied. Non-ionic polyethylene dispersions and a cationic silicone softener micro-emulsion in different concentrations and combinations were considered in this investigation.
It was found that a combination of silicone and polyethylene based softeners presents the most interesting cost/performance behavior.This work has been funded by FEDER through Programa Operacional Factores de Competitividade - COMPETE and by national funds by FCT - Fundacao para a Ciencia e a Tecnologia in the context of project PEst-C/CTM/UI0264/2011
A Hybrid Heuristic for the k-medoids Clustering Problem
Clustering is an important tool for data analysis, since it allows the exploration of datasets with no or very little prior information. Its main goal is to group a set of data based on their similarity (dissimilarity). A well known mathematical formulation for clustering is the k-medoids problem. Current versions of k-medoids rely on heuristics, with good results reported in the literature. However, few methods that analyze the quality of the partitions found by the heuristics have been proposed. in this paper, we propose a hybrid Lagrangian heuristic for the k-medoids. We compare the performance of the proposed Lagrangian heuristic with other heuristics for the k-medoids problem found in literature. Experimental results presented that the proposed Lagrangian heuristic outperformed the other algorithms.UNIFESP, Inst Ciencia & Tecnol, BR-12230280 Sao Jose Dos Campos, SP, BrazilUNIFESP, Inst Ciencia & Tecnol, BR-12230280 Sao Jose Dos Campos, SP, BrazilWeb of Scienc
Antibacterial potential of northeastern Portugal wild plant extracts and respective phenolic compounds
The present work aims to assess the antibacterial potential of phenolic extracts, recovered from plants obtained on the North East of Portugal, and of their phenolic compounds (ellagic, caffeic, and gallic acids, quercetin, kaempferol, and rutin), against bacteria commonly found on skin infections. The disk diffusion and the susceptibility assays were used to identify the most active extracts and phenolic compounds. The effect of selected phenolic compounds on animal cells was assessed by determination of cellular metabolic activity. Gallic acid had a higher activity, against gram-positive (S. epidermidis and S. aureus) and gram-negative bacteria (K. pneumoniae) at lower concentrations, than the other compounds. The caffeic acid, also, showed good antibacterial activity against the 3 bacteria used. The gallic acid was effective against the 3 bacteria without causing harm to the animal cells. Gallic and caffeic acid showed a promising applicability as antibacterial agents for the treatment of infected wounds.The authors thank the Foundation for Science and Technology (Portugal) for financial support by the E. Pinho grant (SFRH/BD/62665/2009) and L. Barros grant (SFRH/BPD/4609/2000), and by the projects PEst-OE/EQB/LA0023/2013, PEst-C/CTM/UI0264/2011, and PEst-OE/EQB/LA0023/2013. Also, the authors acknowledge the financial support from FEDER through Programa Operacional Factores de Competitividade-COMPETE and to COMPETE/QREN/EU (CIMO strategic project 19 PEst-OE/AGR/UI0690/2011), and through the Project "BioHealth-Biotechnology and Bioengineering approaches to improve health quality", Ref. NORTE-07-0124-FEDER-000027, co-funded by the Programa Operacional Regional do Norte (ON.2-O Novo Norte), QREN, FEDER. The authors also acknowledge the project "Consolidating Research Expertise and Resources on Cellular and Molecular Biotechnology at CEB/IBB", Ref. FCOMP-01-0124-FEDER-027462
On Strong Convergence to Equilibrium for the Boltzmann Equation with Soft Potentials
The paper concerns - convergence to equilibrium for weak solutions of
the spatially homogeneous Boltzmann Equation for soft potentials (-4\le
\gm<0), with and without angular cutoff. We prove the time-averaged
-convergence to equilibrium for all weak solutions whose initial data have
finite entropy and finite moments up to order greater than 2+|\gm|. For the
usual -convergence we prove that the convergence rate can be controlled
from below by the initial energy tails, and hence, for initial data with long
energy tails, the convergence can be arbitrarily slow. We also show that under
the integrable angular cutoff on the collision kernel with -1\le \gm<0, there
are algebraic upper and lower bounds on the rate of -convergence to
equilibrium. Our methods of proof are based on entropy inequalities and moment
estimates.Comment: This version contains a strengthened theorem 3, on rate of
convergence, considerably relaxing the hypotheses on the initial data, and
introducing a new method for avoiding use of poitwise lower bounds in
applications of entropy production to convergence problem
Epidemiology and Clinical Forms of Primary Hyperparathyroidism: A Review
Primary hyperparathyroidism (PHPT) is a disease caused by overactive parathyroid glands with consequent hypercalcemia. However, its presentation is variable, with patients demonstrating a range from normocalcemia to severe hypercalcemic PHPT. The present study aims to perform a literature review on the epidemiology and the clinical forms of PHPT using information published in the PubMed and Cochrane databases. It describes data about prevalence, etiology, diagnosis, classic and non-classic manifestations, providing updated information on classical hypercalcemic hyperthyroidism, in addition to its normocalcemic variant
Ferromagnetic Levan Composite: An Affinity Matrix to Purify Lectin
A simple and inexpensive procedure used magnetite and levan to synthesize a composite recovered by a magnetic field. Lectins from Canavalia ensiformis (Con A) and Cratylia mollis (Cramoll 1 and Cramoll 1, 4) did bind specifically to composite. The magnetic property of derivative favored washing out contaminating proteins and recovery of pure lectins with glucose elution. Cramoll 1 was purified by this affinity binding procedure in two steps instead of a previous three-step protocol with ammonium sulfate fractionation, affinity chromatography on Sephadex G-75, and ion exchange chromatography through a CM-cellulose column
Effectiveness of different cellulose-based filtration materials against inhalation of SARS-CoV-2-like particles
The respiratory protection equipment (RPE) used by health professionals consists of an essential device to prevent infectious diseases, especially those caused by biological agents such as the coronavirus (SARS-CoV-2). The current epidemiological panorama is worrying, and the context of creation and production of the mask has emerged as an alternative to RPE to face the public health crisis worldwide. The aim of this work is to present a low-cost alternative as an FFP2-like filter for a reusable respirator face mask. This study presents the comparison of different cellulose-based filtering materials performed by retention testing, time saturation testing, aerosol penetration testing, nanoparticle (~140 nm) filtration testing, bacterial filtration efficiency (BFE), analysis of material morphology and usability. The reusable respirator face mask used in this study is an open-source innovation, using 3D printing. Cotton disc proved to be the best filter material for the reusable mask, with satisfactory results and a performance similar to that shown by the N95-type mask. The cotton disc ensured effectiveness over 6 h of use, and after that, the reusable respirator face mask (here, Delfi-TRON®) needed to be sanitized and replenished with a new cotton disc. Upon preliminary analyses of filtration efficiency, the selected filter was shown to be a low-cost biodegradable and biocompatible alternative.info:eu-repo/semantics/publishedVersio
Limites e possibilidades da Educação Ambiental em uma escola municipal agrícola de ensino fundamental
Ao compreendermos a educação enquanto formação humana intencional para a vida em sociedade, trazemos seu papel como possibilidade de transformação e pressupomos a transversalidade do tema meio ambiente. A análise do Projeto Político Pedagógico (PPP) de uma Escola Municipal Agrícola de Ensino Fundamental do Estado de São Paulo - Brasil, mediante as três possíveis dimensões da Educação Ambiental (EA), nos permitiu verificar: desafios, como a necessidade de reconhecimento da comunidade local articulada às questões globais, e perspectivas para trabalhos futuros a partir de ligações entre as dimensões da EA no PPP
Integração curricular do tema agropecuária em uma escola municipal agrícola : sentidos construídos
Considerando os desafios da educação ambiental para o enfrentamento da crise ambiental, este recorte de pesquisa, de natureza qualitativa, analisou os enunciados dos professores de uma escola agrícola (Rio Claro, SP, Brasil), buscando compreender como têm integrado o tema Agropecuária em suas práticas. Buscando a construção de sentidos sob uma perspectiva bakhtiniana, a leitura dos enunciados iniciais dos professores indicou que maioria dos professores o considera importante e indicam integrá-lo com frequência em suas atividades. No entanto, este não parece ser problematizado: os sentidos produzidos parecem distantes de romper, por meio da crítica, com o discurso hegemônico sobre a questão agropecuária
Total soluble solids from banana: evaluation and optimization of extraction parameters
Banana, an important component in the diet of the global population, is one of the
most consumed fruits in the world. This fruit is also very favorable to industry processes (e.g.,
fermented beverages) due to its rich content on soluble solids and minerals, with low acidity.
The main objective of this work was to evaluate the influence of factors such as banana weight
and extraction time during a hot aqueous extraction process on the total soluble solids content
of banana. The extract is to be used by the food and beverage industries. The experiments were
performed with 105 mL of water, considering the moisture of the ripe banana (65%). Total
sugar concentrations were obtained in a beer analyzer and the result expressed in degrees Plato
(°P, which is the weight of the extract or the sugar equivalent in 100 g solution at 20 °C), aiming
at facilitating the use of these results by the beverage industries. After previous studies of
characterization of the fruit and of ripening performance, a 22 full-factorial star design was
carried out, and a model was developed to describe the behavior of the dependent variable
(total soluble solids) as a function of the factors (banana weight and extraction time),
indicating as optimum conditions for extraction 38.5 g of banana at 39.7 min.Gabinete de Relações Internacionais da Ciência e do Ensino Superior (GRICES), Portugal.Fundação de Amparo à Pesquisa do Estado de São Paulo (Fapesp), Brasil.Coordenação para Aperfeiçoamento do Ensino Superior (CAPES), Brasil.Fundação para a Ciência e Tecnologia (FCT), Portugal
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