26 resultados para Combined Web crippling and Flange Crushing
Resumo:
The present study aims to compare yield and quality of pequi pulp oil when applying two distinct processes: in the first, pulp drying in a tray dryer at 60ºC was combined with enzymatic treatment and pressing to oil extraction; in the second, a simple process was carried out by combining sun-drying pulp and pressing. In this study, raw pequi fruits were collected in Mato Grosso State, Brazil. The fruits were autoclaved at 121ºC and stored under refrigeration. An enzymatic extract with pectinase and CMCase activities was used for hydrolysis of pequi pulp, prior to oil extraction. The oil extractions were carried out by hydraulic pressing, with or without enzymatic incubation. The oil content in the pequi pulp (45% w/w) and the physicochemical characteristic of the oil was determined according to standard analytical methods. Free fatty acids, peroxide values, iodine and saponification indices were respectively 1.46 mgKOH/g, 2.98 meq/kg, 49.13 and 189.40. The acidity and peroxide values were lower than the obtained values in commercial oil samples, respectively 2.48 mgKOH/g and 5.22 meq/kg. Aqueous extraction has presented lower efficiency and higher oxidation of unsaturated fatty acids. On the other hand, pequi pulp pressing at room temperature has produced better quality oil. However its efficiency is still smaller than the combined enzymatic treatment and pressing process. This combined process promotes cellular wall hydrolysis and pulp viscosity reduction, contributing to at least 20% of oil yield increase by pressing.
Resumo:
The abatement of recalcitrant lignin macromolecules from effluents of pulp and paper industry was investigated by combined process. Flocculation and coagulation with aluminum sulfate and natural polyelectrolytes extracted from cactus Cereus peruvianus were used in the first step. After separation of solid residues by filtration, the photochemical methods using TiO2 as catalyst were employed for photocatalytic degradation of lignin compounds from solution. The abatement of lignin compounds after flocculation and coagulation was 46%, and after the overall process, the pollutants reduction observed were 66%. The remaining organic compounds may be removed by any biological treatment.
Resumo:
The development of new tools for chemoinformatics, allied to the use of different algorithms and computer programmes for structure elucidation of organic compounds, is growing fast worldwide. Massive efforts in research and development are currently being pursued both by academia and the so-called chemistry software development companies. The demystification of this environment provoked by the availability of software packages and a vast array of publications exert a positive impact on chemistry. In this work, an overview concerning the more classical approaches as well as new strategies on computer-based tools for structure elucidation of organic compounds is presented. Historical background is also taken into account since these techniques began to develop around four decades ago. Attention will be paid to companies which develop, distribute or commercialize software as well as web-based and open access tools which are currently available to chemists.
Resumo:
Numerous investigations are dedicated to the research and development of new polymer materials destined for innovation in pharmaceutical forms. The application of these technological resources has allowed the commercialization of new therapeutic systems for modified drug release. This investigation aimed to evaluate the association of modified chondroitin sulfate with an insoluble polymer, Eudragit® RS 30 D, widely available in the pharmaceutical market. Isolated films were prepared by the evaporation process using a Teflon® plate. The aqueous dispersions (4% m/v) of synthetic polymer received the addition of modified chondroitin sulfate at different ratios. The interactions of the polymer chains in the blends were physicochemically characterized by means of Fourier transform infrared spectroscopy, thermal analyses, differential scanning calorimetry, thermogravimetry and scanning electron microscopy combined with hydration and assays in alkaline pH. The results showed appropriate properties of the coating materials for solid oral forms intended for drug deliver in specific environments.
Resumo:
Bleeding remains a common and a potential lethal complication for peptic ulcer disease. Multidisciplinary approach by endoscopists, surgeons and intensive care physicians is necessary to improve results for this severe complication. In this article we intend to introduce surgeons and intensive care physicians to endoscopic concepts and maneuvers commonly used in the treatment of bleeding peptic ulcer disease. Early clinical assessment and endoscopic evaluation are helpful to classify the severity of the bleeding episode. Two major achievements have changed the management of this complication: combined endoscopic therapy and proton pump inhibitors. The former consists of combining two different endoscopic methods to stop bleeding or prevent re-bleeding (e.g., injection of a sclerosing substance and thermal coagulation). Surgical treatment for peptic ulcer bleeding is indicated when endoscopic therapy fails or to prevent re-bleeding in high risk patients who presents with a spurting bleeding ulcer and shock. For the remaining situations, there are consistent evidences that a second endoscopic therapy should be attempted when re-bleeding occurs. Keywords: endoscopic hemostasis, recurrent bleeding, peptic ulcer bleeding, proton-pump inhibitor, non-variceal gastrointestinal bleeding.
Resumo:
In less than twenty years, what began as a concept for the treatment of exsanguinating truncal trauma patients has become the primary treatment model for numerous emergent, life threatening surgical conditions incapable of tolerating traditional methods. Its core concepts are relative straightforward and simple in nature: first, proper identification of the patient who is in need of following this paradigm; second, truncation of the initial surgical procedure to the minimal necessary operation; third, aggressive, focused resuscitation in the intensive care unit; fourth, definitive care only once the patient is optimized to tolerate the procedure. These simple underlying principles can be molded to a variety of emergencies, from its original application in combined major vascular and visceral trauma to the septic abdomen and orthopedics. A host of new resuscitation strategies and technologies have been developed over the past two decades, from permissive hypotension and damage control resuscitation to advanced ventilators and hemostatic agents, which have allowed for a more focused resuscitation, allowing some of the morbidity of this model to be reduced. The combination of the simple, malleable paradigm along with better understanding of resuscitation has proven to be a potent blend. As such, what was once an almost lethal injury (combined vascular and visceral injury) has become a survivable one.
Resumo:
The mathematical model for two-dimensional unsteady sonic flow, based on the classical diffusion equation with imaginary coefficient, is presented and discussed. The main purpose is to develop a rigorous formulation in order to bring into light the correspondence between the sonic, supersonic and subsonic panel method theory. Source and doublet integrals are obtained and Laplace transformation demonstrates that, in fact, the source integral is the solution of the doublet integral equation. It is shown that the doublet-only formulation reduces to a Volterra integral equation of the first kind and a numerical method is proposed in order to solve it. To the authors' knowledge this is the first reported solution to the unsteady sonic thin airfoil problem through the use of doublet singularities. Comparisons with the source-only formulation are shown for the problem of a flat plate in combined harmonic heaving and pitching motion.
Resumo:
Fetal hemoglobin was measured in HIV1/2 patients under treatment with combined therapy (zidovudine and a protease inhibitor). A total of 143 patients and 103 normal individuals were investigated by the quantitative method of Betke and the semi-quantitative acid elution method of Kleihauer. In the normal person, hemoglobin F makes up less than 1% and an increase higher than 1.5% was observed in 21.4% of HIV patients by the method of Betke and in 24.8% of HIV-infected patients by the method of Kleihauer. The quantitative biochemical method of Betke showed that the populations were significantly different (two-tailed Mann-Whitney test). The reason for this hemoglobin F increase might be ascribed to the effect of zidovudine or to direct viral action on gamma chain expression. The finding of a higher F cell frequency indicated by the method of Kleihauer rather suggests that there is an increased F cell clone proliferation rather than an increase in hemoglobin F level in every cell.
Resumo:
The periaqueductal gray (PAG) has been traditionally considered to be an exit relay for defensive responses. Functional mapping of its subdivisions has advanced our knowledge of this structure, but synthesis remains difficult mainly because results from lesion and stimulation studies have not correlated perfectly. After using a strategy that combined both techniques and a reevaluation of the available literature on PAG function and connections, we propose here that freezing could be mediated by different PAG subdivisions depending on the presence of immediate danger or exposure to related signaling cues. These subdivisions are separate functional entities with distinct descending and ascending connections that are likely to play a role in different defensive responses. The existence of ascending connections also suggests that the PAG is not simply a final common path for defensive responses. For example, the possibility that indirect ascending connections to the cingulate cortex could play a role in the expression of freezing evoked by activation of the neural substrate of fear in the dorsal PAG has been considered.
Resumo:
The aim of this study was to determine the impact of antiretroviral therapy on the lipid profile of human immunodeficiency virus (HIV) patients before and after the initiation of highly active antiretroviral therapy (HAART). This was a cross-sectional analysis of patients receiving HAART at a reference center in Belo Horizonte, Brazil, on the basis of medical records from 2002 to 2006. Patients were included if they had at least one lipid test or a clinical or laboratory diagnosis of dyslipidemia/lipodystrophy. Among the 692 patients, 620 met the eligibility criteria. The majority were males (66.5%), middle age (average 39 years), had a low educational level (60.4%), and low income (51.0%). HAART duration ranged from 11 days to 4.6 years, with a mean of 28.6 months (SD = ± 470.19 days). The prevalence of dyslipidemia/lipodystrophy nearly tripled (11.3% pre- and 32.4% post-HAART). Dyslipidemia was associated with older age (P = 0.007), nucleoside reverse transcriptase inhibitor (NRTI) + protease inhibitor (PI) regimens (P = 0.04), NRTI + non-NRTI (NNRTI) regimens (P = 0.026), the use of stavudine (d4T) in any regimen (P = 0.002) or in NRTI-based regimens (P = 0.006), and longer exposure to HAART (P < 0.000). In addition, there was no correlation between dyslipidemia and gender (P = 0.084). Only 2.0% of the patients received treatment for dyslipidemia during the trial. These results show a need for continuous monitoring of patients under antiretroviral therapy, particularly those using NRTI-based regimens, especially when combined with d4T and PIs. Secondly, interventions should be developed to correct metabolic changes.
Resumo:
Stability of minimally processed radicchio (Cichorium intybus L.) was evaluated under modified atmosphere (2% O2, 5% CO2, and 93% N2) on 3, 5, 7 and 10 days of storage at 5°C. The samples were hygienized in sodium hypochlorite or hydrogen peroxide solutions to identify the most effective sanitizing solution to remove microorganisms. Microbiological analysis was conducted to identify the presence of coliforms at 35°C and 45°C, mesophilic microorganisms, and yeast and mold. Physicochemical analyses of mass loss, pH, soluble solids, and total acidity were conducted. The color measurements were performed using a Portable Colorimeter model CR-400. The antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic methods. The sensory evaluation was carried out using a hedonic scale to test overall acceptance of the samples during storage. The sodium hypochlorite (150 mg.L-1) solution provided greater safety to the final product. The values of pH ranged from 6.17 to 6.25, total acidity from 0.405 to 0.435%, soluble solids from 0.5 to 0.6 °Brix, mass loss from 1.7 to 7.2%, and chlorophyll from 1.068 to 0.854 mg/100g. The antioxidant activity of radicchio did not show significant changes during the first 3 days of storage. The overall acceptance of the sample stored in the sealed package without modified atmosphere was 70%, while the fresh sample was obtained 77% of approval. Although the samples packaged under modified atmosphere had a higher acceptance score, the samples in sealed packages had satisfactory results during the nine days of storage. The use of modified atmosphere, combined with cooling and good manufacturing practices, was sufficient to prolong the life of minimally processed radicchio, Folha Larga cultivar, for up to ten days of storage.