Multiobjective optimization of economic balances of sugarcane harvest biomass

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Integração de modelos de localização a sistemas de informações geográficas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Proposta de avanço para o método Tambor-Pulmão-Corda Simplificado aplicado em ambientes de produção sob encomenda

Recentes aplicações da Teoria das Restrições em Gestão de Operações têm adotado o chamado método Tambor-Pulmão-Corda Simplificado (S-DBR - Simplified Drum-Buffer-Rope) como padrão para planejamento e controle da produção. Contudo, poucas são as referências bibliográficas, especialmente em periódicos nacionais e internacionais, que relatam seus principais conceitos e premissas. Este artigo se propõe a apresentar o método S-DBR para planejamento da produção e sua correspondente abordagem de controle da produção denominado Gerenciamento do Pulmão, aqui abordados em ambientes de produção sob encomenda (MTO - make to order), suas principais características, pressupostos e diferenças em relação ao método DBR clássico. É também apresentada uma proposta complementar ao método S-DBR para estabelecer promessas de entregas urgentes mantendo elevada probabilidade de entrega no prazo.

Matéria-prima da formação Corumbataí na região do pólo cerâmico de Santa Gertrudes, SP, com características naturais para fabricação de argila expandida

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Peso adulto de matrizes em rebanhos de seleção da raça Nelore no Brasil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Dos desvios das médias dos grupos contemporâneos aos modelos animais

O objetivo deste trabalho foi apresentar a reparametrização de um modelo de desvios das médias dos grupos contemporâneos até um modelo animal não-restrito (equações dos modelos mistos de Lush - EMML). Aplicando restrições sobre as EMML, foi obtido o modelo animal segundo Henderson (equações dos modelos mistos de Henderson - EMMH). Para obter as EMMH, restrições do tipo X'A-1λ aH = 0 foram impostas e estas geraram a necessidade de pressuposições fortes, como ausência de seleção, para que as propriedades das EMMH pudessem ser provadas. Para diferentes situações examinadas, as restrições foram confirmadas. O somatório destas restrições pode ser erroneamente interpretado como propriedade das soluções de um modelo animal de que os animais-base tenham a soma dos seus valores genéticos igual a zero.

Synthesis and characterization of phosphorylcholine-substituted chitosans soluble in physiological pH conditions

A polymer analogous synthesis involving the reductive amination of phosphorylcholine (PC)-glyceraldehyde with primary amines of deacetylated chitosan (M-w approximate to 57000 g mol(-1)) was used to prepare phosphorylcholine-substituted chitosans (PC-CH) with a degree of substitution (DS) ranging from similar to 11 to similar to 53 mol% PC-substituted glucosamine residues. The PC-CH derivatives were characterized by H-1 NMR spectroscopy, FTIR spectroscopy, and multiangle laser light scattering gel permeation chromatography (MALLS-GPC). The pKa of the PC-substituted amine groups (pKa approximate to 7.20) was determined by H-1 NMR titration. The PC-CH samples (1.0 g L-1) were shown to be nontoxic using an MTT assay performed with human KB cells. Aqueous solutions of PC-CH samples (4.0 g L-(1)) of DS g 22 mol% PC-substituted glucosamine residues remained clear, independently of pH (4.0 < pH < 11.0). The remarkable water solubility and nontoxicity displayed by the new PC-CH samples open up new opportunities in the design of chitosan-based biomaterials and nanoparticles.

Effects of ion beam on nanoindentation characteristics of glassy polymeric carbon surface

Glassy polymeric carbon (GPC) is a useful material for medical applications due to its chemical inertness and biocompatible characteristics. Mitral and aortic and hydrocephalic valves are examples of GPC prosthetic devices that have been fabricated and commercialized in Brazil. In this work, ion beam was used to improve the mechanical characteristics of GPC surface and therefore to avoid the propagation of microcracks where the cardiac valves are more fragile. A control group of phenolic resin samples heat-treated at 300, 400, 700, 1000, 1500, and 2500 degrees C was characterized by measuring their hardness and Young's reduced elastic modulus with the depth of indentation. The control group was compared to results obtained with samples heat-treated at 700, 1000, and 1500 degrees C and bombarded with energetic ions of silicon, carbon, oxygen, and gold at energies of 5, 6, 8, and 10 MeV, respectively, with fluences between 10x10(13) and 10x10(16) ions/cm(2). GPC nonbombarded samples showed that hardness depends on the heat treatment temperature (HTT), with a maximum hardness for heat treatment at 1000 degrees C. The comparison between the control group and bombarded group also showed that hardness, after bombardment, had a greater increase for samples prepared at 700 degrees C than for samples prepared at higher temperatures. The Young's elastic modulus presents an exponential relationship with depth. The parameters obtained by fitting depend on the HTT and on the ion used in the bombardment more than on energy and fluence. The hardness results show clearly that bombardment can promote carbonization, increase the linkage between the chains of the polymeric material, and promote recombination of broken bonds in lateral groups that are more numerous for samples heat-treated at 700 degrees C. (c) 2004 Elsevier B.V. All rights reserved.

Degree of conversion and molecular weight of one denture base and three reline resins submitted post-polymerization treatments

The effect of post-polymerization treatments (MW-microwave irradiatron and WB-water-bath) on the degree of conversion (DC) of three reline resins (Ufi Gel hard-U, Kooliner-K, and Tokuso Rebase Fast-T) and one denture base resin (Lucitone 550-L), submitted to two polymerization cycles (LS-short and LL-long), was evaluated by using FT-Raman spectroscopy (n = 5). The molecular weight (Mw) of the powder of all materials and of K polymerized specimens (control; MW; and WB; n = 3) was analyzed using GPC. DC data were analyzed using Kruskal-Wallis test (α = .05). For control specimens, there were no significant differences between U (68%) and LL (77%) and among LL, K (81%), and T (84%). LS (92%) had the highest DC (P<0.05). Only material K exhibited an increased DC after WB (P<0.05). All powders had Mw from 4.0 × 105 to 6.5 × 105 and narrow Mw distributions (2.1 to 3.6). Polymerization and post-polymerization produced K specimens with Mw similar to that of K powder.

Aspectos estruturais da membrana eritrocitária

This article describes the structures and functions of the erythrocyte membrane and its importance in transfusional medicine. The erythrocyte membrane is one of the best known membranes in terms of structure, function and genetic disorders. As any other plasma membrane, it mediates transport functions. It also provides the erythrocytes with their resilience and deformability. According to the International Society of Blood Transfusion (ISBT), more than 500 antigens are expressed in the erythrocyte membrane, and around 270 are involved in transfusion reaction cases and hemolytic diseases of the fetus and newborn. In the ISBT classification, the high frequency series is represented by antigens in more than 99% of population (high prevalence antigen). In transfusion, the absence of these antigens determines severe problems as for example, one woman without the P antigen suffered 6 repetitive miscarriages due to placental insufficiency, which was caused by an antibody formed against the absent P antigen. Some important erythrocyte membrane proteins are described here including Band 3, Glycophorins and spectrin. The most abundant integral membrane protein is Band 3 and its main function is to mediate exchange of chloride and bicarbonate anions across the plasma membrane. The second most abundant integral membrane protein in the human erythrocyte is sialoglycoprotein glycophorin A (GPA). With its high sialic acid content, GPA is the main contributor to the net negative cell-surface charge and is thus critical for minimizing cell-cell interactions and preventing red cell aggregation. Glycophorin C (GPC) is the receptor for PfEBP-2 (baebl, EBA-140), the newly identified erythrocyte binding ligand of Plasmodium falciparum. The ternary complex of spectrin, actin and 4.1R defines the nodes of the erythrocyte membrane skeletal network, and is inseparable from membrane stability when under mechanical stress. This erythrocyte membrane review is important for a better understanding of transfusion reactions, where the antibody formation against high prevalence antigens makes compatible transfusions difficult. The study of antigen diversity and biochemical characterization of different proteins will contribute to healthcare, as well as diagnosis, development of technology such as monoclonal antibody production and the therapeutic conduct of many diseases.

Toxicidade de fármacos nitrofurânicos

During the structural designing of new drugs, it is possible predict the influence of specific chemical groups on pharmacological activity. Among these, the nitro group has potential antiparasitic activity, being present in many antimicrobial drugs, such as metronidazole, nitrofurazone, furazolidone, oxamniquine and chloramphenicol. Also, the introduction of the nitro group into a molecule can modify the physicochemical and electronic properties of the substance. Besides antimicrobial drugs, this group is also found in other drug classes, such as antiulcer, anti-inflamatory and anxiolytic. However, the use of the nitro group in drug design has encountered restrictions, due to the associated toxicity. This article is a review of the toxicity of nitrofuran compounds, as well the possible mechanisms involved and the strategy of latentiation by molecular modification to decrease their toxicity.