977 resultados para Reaching


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The most disabling aspect of human peripheral nerve injuries, the majority of which affect the upper limbs, is the loss of skilled hand movements. Activity-induced morphological and electrophysiological remodeling of the neuromuscular junction has been shown to influence nerve repair and functional recovery. In the current study, we determined the effects of two different treatments on the functional and morphological recovery after median and ulnar nerve injury. Adult Wistar male rats weighing 280 to 330 g at the time of surgery (N = 8-10 animals/group) were submitted to nerve crush and 1 week later began a 3-week course of motor rehabilitation involving either "skilled" (reaching for small food pellets) or "unskilled" (walking on a motorized treadmill) training. During this period, functional recovery was monitored weekly using staircase and cylinder tests. Histological and morphometric nerve analyses were used to assess nerve regeneration at the end of treatment. The functional evaluation demonstrated benefits of both tasks, but found no difference between them (P > 0.05). The unskilled training, however, induced a greater degree of nerve regeneration as evidenced by histological measurement (P < 0.05). These data provide evidence that both of the forelimb training tasks used in this study can accelerate functional recovery following brachial plexus injury.

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In numerous motor tasks, muscles around a joint act coactively to generate opposite torques. A variety of indexes based on electromyography signals have been presented in the literature to quantify muscle coactivation. However, it is not known how to estimate it reliably using such indexes. The goal of this study was to test the reliability of the estimation of muscle coactivation using electromyography. Isometric coactivation was obtained at various muscle activation levels. For this task, any coactivation measurement/index should present the maximal score (100% of coactivation). Two coactivation indexes were applied. In the first, the antagonistic muscle activity (the lower electromyographic signal between two muscles that generate opposite joint torques) is divided by the mean between the agonistic and antagonistic muscle activations. In the second, the ratio between antagonistic and agonistic muscle activation is calculated. Moreover, we computed these indexes considering different electromyographic amplitude normalization procedures. It was found that the first algorithm, with all signals normalized by their respective maximal voluntary coactivation, generates the index closest to the true value (100%), reaching 92 ± 6%. In contrast, the coactivation index value was 82 ± 12% when the second algorithm was applied and the electromyographic signal was not normalized (P < 0.04). The new finding of the present study is that muscle coactivation is more reliably estimated if the EMG signals are normalized by their respective maximal voluntary contraction obtained during maximal coactivation prior to dividing the antagonistic muscle activity by the mean between the agonistic and antagonistic muscle activations.

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Negotiating trade agreements is an important part of government trade policies, economic planning and part of the globally operating trading system of today. European Union and the United States have been active in the formation of trade agreements in global comparison. Now these two economic giants are engaged in negotiations to form their own trade agreement, the so called Transnational Trade and Investment Partnership (TTIP). The purpose of this thesis is to understand the reasons for making a trade agreement between two economic areas and understanding the issues it may include in the case of the TTIP. The TTIP has received a great deal of attention in the media. The opinions towards the partnership have been extreme, and the debate has been heated. The purpose of this study is to introduce the nature of the public discussion regarding the TTIP from Spring 2013 until 2014. The research problem is to find out what are the main issues in the agreement and what are the values influencing them. The study was conducted applying methods of critical discourse analysis to the chosen data. This includes gathering the issues from the data based on the attention each has received in the discussion. The underlying motives for raising different issues were analysed by investigating the authors’ position in the political, economic and social circuits. The perceived economic impacts of the TTIP are also under analysis with the same criteria. Some of the most respected economic newspapers globally were included in the research material as well as papers or reports published by the EU and global organisations. The analysis indicates a clear dichotomy of the attitudes towards the TTIP. Key problems include lack of transparency in the negotiations, the misunderstood investor-state dispute settlement, the constantly expanding regulatory issues and the risk of protectionism. The theory and data does suggest that the removal of tariffs is an effective tool for reaching economic gains in the TTIP and even more effective would be the reducing of non-tariff barriers, such as protectionism. Critics are worried over the rising influence of corporations over governments. The discourse analysis reveals that the supporters of the TTIP have values related to increasing welfare through economic growth. Critics do not deny the economic benefits but raise the question of inequality as a consequence. Overall they represent softer values such as sustainable development and democracy as a counter-attack to the corporate values of efficiency and the maximising of profits.

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The aim of this study is to assess sugar cane juice and sucrose as substrates, the batch and fed batch processes and their interaction in the levan production using a complete factorial design. Zymomonas mobilis was cultivated in different sugar cane juice and sucrose concentrations in two fermentation processes at 25 °C for 20 h. A complete factorial design (2³) was used to analyze the effects of the type and concentration of the substrate, as well as the batch and fed batch processes. A complete second factorial design (2²) was used to observe the importance of sugar cane juice. The results indicated that the batch process improved the levan production reaching 40.14 g/L. The addition of sugar cane juice was not statistically significant for levan formation, however sugar cane juice stimulated biomass, sorbitol and ethanol production. The best medium for levan production was 150 g/L sucrose in batch.

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The use of liquid cassava waste (manipueira) as the medium for the biotransformation of citronellol using a Penicillium sp strain was studied. The strain was able to grow in the waste and production of cellular mass reaching 25 g/L over three days of contact of the spores with the medium. Submerged cultures of Penicillium sp grown in manipueira were able to convert the substrate into cis- and trans-rose oxides when the cells were transferred into a mineral medium for the biotransformation experiments. The production of rose oxide increased by more than 2.4 times using this 2 media process as compared to processes using only a manipueira medium (cassava medium). Auto-oxidation products were not detected in the control experiments.

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The adherence of Pseudomonas fluorescens cells to nine food-processing contact surfaces was evaluated using the plate-count method. The surfaces include marble, granite, stainless steel, polyvinyl chloride, polyurethane, and silicone-coated cloth, which have been used only in a few studies concerning bacterial adherence. The number of cells adhered to the surfaces increased with contact time reaching 5.0-6.1 log CDM.cm-2 after 10 hours, which can be considered a well established adherence process. The number of adhered cells doubled in 29.5 minutes and 23.5 minutes on stainless steel and thin polyvinyl chloride-coated cloth, respectively. For the other surfaces, this value was 9.8 minutes on average. Marble, granite, thick polyvinyl-coated cloth, double-faced rugous polyurethane, and silicone-coated cloth were not different (p < 0.05) in their ability to adhere cells (CFU/cm²) after 2 and 10 hours. The surfaces that had higher percentage of similarity in the adhesion level and higher log CFU/cm² of adhered cells were double-faced rugous polyurethane, silicone-coated cloth, and granite. The surfaces showed very different microtopography characteristics when viewed using scanning electron microscopy. This experiment showed the importance of using appropriate materials for food contact during processing, which will affect the cleaning and sanitation procedures.

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The common bean (Phaseolus vulgaris L.) is a staple food in the Brazilian diet and represents the major source of dietary protein and other micronutrients and minerals. Despite the considerable protein concentration in beans, the food is considered of low biological value when compared to animal proteins and other plant protein sources. To improve the availability of protein in beans, enzymatic treatments were performed in four cultivars (ON, OPNS, TAL and VC3). The approach was a completely randomized design with four replicates. We used a 4 × 3 factorial arrangement (four cultivars and three treatments: treatment 1-addition of commercial protease (Trypsin 250, Difco), treatment 2-addition of protease from Bacillus sp., and treatment 3:-control without enzyme addition). The enzyme: substrate ratio was 5% w/w (amount of enzyme per total protein in bean flour). The approach was a completely randomized design with four replicates. A 4 × 3 factorial arrangement (four cultivars and three treatments, the same as those mentioned above) was used. The concentration of total protein (g.100 g-1 of dry matter) in the samples ranged from 16.94 to 18.06%, while the concentration of total phenolics was between 0.78 and 1.12% (g Eq. tannic acid.100 g-1 dry matter). The in vitro protein digestibility of enzymatically untreated bean flour (control) ranged from 47.30 to 56.17% based on the digestibility of casein. Concentrations of P, K, Ca, Mg, and Zn observed in the four cultivars tested were within the average values available in the literature. Treatment 2 with protease from Bacillus sp. induced decreases in the levels of Cu and Mn. The average Fe content increased in all bean flour samples when treated with proteases, reaching a maximum increase of 102% in the TAL flour treated with protease from Bacillus sp. The digestibility of all beans tested was significantly increased (p < 0.05) after the enzyme treatment. The greatest change was observed in the OPNS cultivar treated with protease from Bacillus sp., which increased its digestibility from 54.4% (control treatment) to 81.6%.

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Polygalacturonase production by the thermophilic Bacillus sp. SMIA-2 cultivated in liquid cultures containing 0.5% (w/v) apple pectin and supplemented with 0.3% (w/v) corn steep liquor, reached its maximum after 36 hours with levels of 39 U.mL-1. The increase in apple pectin and corn steep liquor concentrations in the medium from 0.5 and 0.3%, respectively, to 0.65%, markedly affected the production of polygalacturonase, whose activity increased four times, reaching a maximum of 150.3 U.mL-1. Studies on polygalacturonase characterization revealed that the optimum temperature of this enzyme was between 60-70 °C. Thermostability profile indicated that the enzyme retained about 82 and 63% of its activity at 60 and 70 °C, respectively, after 2 hours of incubation. The optimum pH of the enzyme was found to be 10.0. After incubation of crude enzyme solution at room temperature for 2 hours at pH 8.0, a decrease of about 29% on its original activity was observed. At pH 10.0, the decrease was 25%.

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Mimic biological structures such as the cell wall of plant tissues may be an alternative to obtain biodegradable films with improved mechanical and water vapor barrier properties. This study aims to evaluate the mechanical properties and water vapor permeability (WVP) of films produced by using the solvent-casting technique from blended methylcellulose, glucomannan, pectin and gelatin. First, films from polysaccharides at pH 4 were produced. The film with the best mechanical performance (tensile strength = 72.63 MPa; elongation = 9.85%) was obtained from methylcellulose-glucomannan-pectin at ratio 1:4:1, respectively. Then, gelatin was added to this polysaccharide blend and the pH was adjusted to 4, 5 and 6. Results showed significant improvement in WVP when films were made at pH 5 and at polysaccharides/gelatin ratio of 90/10 and 10/90, reaching 0.094 and 0.118 g.mm/h.m².kPa as values, respectively. Films with the best mechanical properties were obtained from the blend of polysaccharides, whereas WVP was improved from the blend of polysaccharides and gelatin at pH 5.

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Physicochemical characteristics and functional properties of vitabosa flour (Mucuna deeringiana) and soybean flour (Glycine max) were determined. Oil absorption capacity was higher in vitabosa. Water absorption capacity was higher in soy and it was affected by the change in the ionic strength of the medium. Emulsifying Activity (EA) decreased with increasing concentration of flour, while Emulsifying Stability (ES) showed an increased. EA and ES of flours have more ionic strength in the range between 0.0 and 0.4 M, but it is reduced afterwards with the higher concentration of NaCl. Foaming stability varied with the concentration of flour solution reaching maximum values of 39 and 33% for vitabosa and soybean, respectively at 10% flour concentration.Vitabosa had the best foaming capacity (56% to 0.6 M) compared with soybeans (47% to 0.4 M). Maximum capacity of gelation was observed in vitabosa at 10% flour concentration. Increases in ionic strength of the flour solution, at low salt concentrations (<0.4 M), improved the gelation of flours.

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The effectiveness of different types of rice in relation to their ability to accelerate diarrhea recovering was evaluated in a rat model of osmotic diarrhea (OD). Animals (90-100 g) received protein free diet until reaching up to 20% weight loss, followed by lactose rich diet (LRD) to induce osmotic diarrhea. Rats presenting osmotic diarrhea were divided into 4 groups, which received lactose rich diet for 4 days from 8 am to 8 pm, and one of three experimental products containing 6% rice flour differing in amylose content during the night: high (HA), intermediate (IA), and low (LA). A group fed stock diet containing equivalent amount of lactose was taken as control and allowed to recover spontaneously. Amylose and viscosity (cp at 25 °C, 10 rpm) of final products were determined. Effectiveness was expressed as the ratio between percentages of normal vs. diarrheic stools during the treatment. Fecal characteristics in this rat model improved only as result of feeding high amylose content (HA) type of rice. In this experimental model of osmotic diarrhea in young rats, the antidiarrheal effects of rice were strongly dependent on the type of diet used and appear to be related to its amylose content.

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Canastra cheese is one of the oldest and most traditional cheeses made from raw milk in Brazil. However, this type of practice may have severe consequences for human health. According to the current legislation, any cheese made from raw milk must be aged for at least 60 days. Traditionally, Canastra cheese is consumed after different ripening periods, but consumers usually prefer those that are aged less than eight days. This study aimed to evaluate the effects of physicochemical and microbiological parameters, with emphasis on the pathogenic microbiota regulated by law, on cheese aged at room temperature and under refrigeration. Cheese samples were collected from eight different cheese producers located in the Serra da Canastra region twice a year (rainy and dry seasons) and analyzed with 8, 15, 22, 29, 36, and 64 days of ripening. Room temperature aging effectively reduced pathogens, reaching the total count established by law in 22 days, regardless of the season. However, ripening under refrigeration, it was ineffective in reducing the Staphylococcus aureus counts to the legislation limits, even after 64 days. Therefore, Canastra cheese should be ripened for at least 22 days at room temperature in order to fulfill the safety regulatory limits.

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The objective of the present study was the isolation of a yeast strain, from citrus fruit peels, able to produce a polygalacturonase by submerged fermentation with maceration activity of raw cassava roots. Among 160 yeast strains isolated from citrus peels, one strain exhibited the strongest pectinolytic activity. This yeast was identified as Wickerhamomyces anomalus by 5.8S-ITS RFLP analysis and confirmed by amplification of the nucleotide sequence. The yeast produced a polygalacturonase (PG) in Erlenmeyer shake flasks containing YNB, glucose, and citrus pectin. PG synthesis occurred during exponential growth phase, reaching 51 UE.mL-1 after 8 hours of fermentation. A growth yield (Yx/s) of 0.43 gram of cell dry weight per gram of glucose consumed was obtained, and a maximal specific growth rate (µm) of 0.346 h-1 was calculated. The microorganism was unable to assimilate sucrose, galacturonic acid, polygalacturonic acid, or citrus pectin, but it required glucose as carbon and energy source and polygalacturonic acid or citrus pectin as inducers of enzyme synthesis. The crude enzymatic extract of Wickerhamomyces anomalus showed macerating activity of raw cassava. This property is very important in the production of dehydrated mashed cassava, a product of regional interest in the province of Misiones, Argentina.

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The search for efficient and accessible cooling systems has increased worldwide. This study aims to build and evaluate an evaporative cooling system using a water driven ejector, allowing it to be installed in places with plenty of water. The system was investigated varying the flow rate and temperature of the circulating water, temperature of the replacement water, and coefficient of performance. The best vacuum obtained was 8.5 kPa at nominal operating conditions of 4.1 ± 0.1 m³/h and 5 ± 0.5 ºC for the circulating water reaching the temperature of 9.7 ± 0.5 ºC. The pulse-like disturbance generated by replacing the cooling water at different periods of times did not result in significant affect vacuum destabilization and the temperature rise in the cooling tank. The coefficient of performance of the system at the highest thermal power of 92.27 W was 0.077, which was underestimated due to possible problems related to pump efficiency. The system evaluated under the conditions proposed can be very efficient for cooling fluids at higher temperatures, and it can be complementary to main refrigeration systems.

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The objective of this study was to characterize the development of pequi fruit (Caryocar brasiliense) of the Brazilian cerrado. It takes 84 days (12 weeks) for pequi to develop with the onset of flowering in September and early fruit set in January. Pequi fruit showed a simple sigmoid growth curve, and its growth was characterized based on fresh mass and longitudinal and transverse diameters. The contents of titratable acidity, soluble solids, β-carotene, and vitamin C increased during fruit growth, reaching their maximum values at the 12th week (84 days) after anthesis. Pequi is a fruit with an extremely high respiratory activity; its respiratory rate decreased during its development. Pequi fruit has been classified as a non-climacteric fruit due to the decrease of both respiration and ethylene production rates during maturation and ripening.