940 resultados para Convective Constraint Release


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Nitric oxide (NO) is a soluble gas that participates in important functions of the central nervous system, such as cognitive function, maintenance of synaptic plasticity for the control of sleep, appetite, body temperature, neurosecretion, and antinociception. Furthermore, during exercise large amounts of NO are released that contribute to maintaining body homeostasis. Besides NO production, physical exercise has been shown to induce antinociception. Thus, the present study aimed to investigate the central involvement of NO in exercise-induced antinociception. In both mechanical and thermal nociceptive tests, central [intrathecal (it) and intracerebroventricular (icv)] pretreatment with inhibitors of the NO/cGMP/KATP pathway (L-NOArg, ODQ, and glybenclamide) prevented the antinociceptive effect induced by aerobic exercise (AE). Furthermore, pretreatment (it, icv) with specific NO synthase inhibitors (L-NIO, aminoguanidine, and L-NPA) also prevented this effect. Supporting the hypothesis of the central involvement of NO in exercise-induced antinociception, nitrite levels in the cerebrospinal fluid increased immediately after AE. Therefore, the present study suggests that, during exercise, the NO released centrally induced antinociception.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This study aimed to determine the effects of different concentrations of propofol (2,6-diisopropylphenol) on lipopolysaccharide (LPS)-induced expression and release of high-mobility group box 1 protein (HMGB1) in mouse macrophages. Mouse macrophage cell line RAW264.7 cells were randomly divided into 5 treatment groups. Expression levels of HMGB1 mRNA were detected using RT-PCR, and cell culture supernatant HMGB1 protein levels were detected using enzyme-linked immunosorbent assay (ELISA). Translocation of HMGB1 from the nucleus to the cytoplasm in macrophages was observed by Western blotting and activity of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in the nucleus was detected using ELISA. HMGB1 mRNA expression levels increased significantly in the cell culture supernatant and in cells after 24 h of stimulating RAW264.7 cells with LPS (500 ng/mL). However, HMGB1 mRNA expression levels in the P2 and P3 groups, which received 500 ng/mL LPS with 25 or 50 μmol/mL propofol, respectively, were significantly lower than those in the group receiving LPS stimulation (P<0.05). After stimulation by LPS, HMGB1 protein levels were reduced significantly in the nucleus but were increased in the cytoplasm (P<0.05). Simultaneously, the activity of NF-κB was enhanced significantly (P<0.05). After propofol intervention, HMGB1 translocation from the nucleus to the cytoplasm and NF-κB activity were inhibited significantly (each P<0.05). Thus, propofol can inhibit the LPS-induced expression and release of HMGB1 by inhibiting HMGB1 translocation and NF-κB activity in RAW264.7 cells, suggesting propofol may be protective in patients with sepsis.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Heavy metals, such as methylmercury, are key environmental pollutants that easily reach human beings by bioaccumulation through the food chain. Several reports have demonstrated that endocrine organs, and especially the pituitary gland, are potential targets for mercury accumulation; however, the effects on the regulation of hormonal release are unclear. It has been suggested that serum prolactin could represent a biomarker of heavy metal exposure. The aim of this study was to evaluate the effect of methylmercury on prolactin release and the role of the nitrergic system using prolactin secretory cells (the mammosomatotroph cell line, GH3B6). Exposure to methylmercury (0-100 μM) was cytotoxic in a time- and concentration-dependent manner, with an LC50 higher than described for cells of neuronal origin, suggesting GH3B6 cells have a relative resistance. Methylmercury (at exposures as low as 1 μM for 2 h) also decreased prolactin release. Interestingly, inhibition of nitric oxide synthase by N-nitro-L-arginine completely prevented the decrease in prolactin release without acute neurotoxic effects of methylmercury. These data indicate that the decrease in prolactin production occurs via activation of the nitrergic system and is an early effect of methylmercury in cells of pituitary origin.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Microparticles obtained by complex coacervation were crosslinked with glutaraldehyde or with transglutaminase and dried using freeze drying or spray drying. Moist samples presented Encapsulation Efficiency (%EE) higher than 96%. The mean diameters ranged from 43.7 ± 3.4 to 96.4 ± 10.3 µm for moist samples, from 38.1 ± 5.36 to 65.2 ± 16.1 µm for dried samples, and from 62.5 ± 7.5 to 106.9 ± 26.1 µm for rehydrated microparticles. The integrity of the particles without crosslinking was maintained when freeze drying was used. After spray drying, only crosslinked samples were able to maintain the wall integrity. Microparticles had a round shape and in the case of dried samples rugged walls apparently without cracks were observed. Core distribution inside the particles was multinuclear and homogeneous and core release was evaluated using anhydrous ethanol. Moist particles crosslinked with glutaraldehyde at the concentration of 1.0 mM.g-1 protein (ptn), were more efficient with respect to the core retention compared to 0.1 mM.g-1 ptn or those crosslinked with transglutaminase (10 U.g-1 ptn). The drying processes had a strong influence on the core release profile reducing the amount released to all dry samples

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this study, the effects of hot-air drying conditions on color, water holding capacity, and total phenolic content of dried apple were investigated using artificial neural network as an intelligent modeling system. After that, a genetic algorithm was used to optimize the drying conditions. Apples were dried at different temperatures (40, 60, and 80 °C) and at three air flow-rates (0.5, 1, and 1.5 m/s). Applying the leave-one-out cross validation methodology, simulated and experimental data were in good agreement presenting an error < 2.4 %. Quality index optimal values were found at 62.9 °C and 1.0 m/s using genetic algorithm.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Mallow leaves (Malva sylvestris L.) with initial moisture of 5.02±0.003 on dry basis (82.5% on wet basis) were dried using three different drying methods, microwave, convective and vacuum. The leaves that weigh 75 g each were dried until their moisture fell down to 0.10±0.005 on dry basis (approximately 9% on wet basis). The following drying levels were used in each of the drying processes: 6.67, 8.67, 10, 11.33 W g-1 microwave power density; 50, 75, 100 and 125 °C for convective drying; and 3, 7 kPa at 50 and 75 °C for vacuum drying. Drying periods ranged from 6-10, 26-150 and 38-130 min. for microwave, convective and vacuum drying, respectively. Effective moisture diffisuvities ranged from 2.04403 10-10-3.63996 10-12 m2 s-1, 1.70182 10-11-1.10084 10-10 m2 s-1 and 1.85599 10-11-5.94559 10-10 m2 s-1 for microwave, convective and vacuum drying, respectively. According to ascorbic acid content and color parameters, the best microwave power density was found 10 W g-1 with a drying period of 6.5 min.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Abstract The present study aimed at investigating the influences of drying air temperature and flow rate on energy parameters and dehydration behaviour of apple slices. For this purpose, apple slices were dried in a convective dryer at air temperatures of 50, 60 and 70 °C, and air velocities of 1, 1.5 and 2 m s–1. Dehydration rate increased as the air temperature and flow rate increased from 50 to 70 °C and 1 to 2 m s–1, respectively. The effective moisture diffusivity was determined to be in the range of 6.75×10–10-1.28×10–9 m2 s–1. Results of data analysis showed that the maximum energy consumption (23.94 kW h) belonged to 50 °C and 2 m s–1 and the minimum (13.89 kW h) belonged to 70 °C and 1 m s–1 treatment. Energy efficiency values were in the range of 2.87-9.11%. Moreover, the results indicated that any increment in the air temperature increases thermal and drying efficiencies while any increment in the air flow rate decreases both of them.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Most tropical forage grass species have dormant seeds, which reduce percentages in germination tests. The objective of this study was to evaluate H2SO4 scarification effects on seed dormancy releasing, through germination time (T50) and variability among germination test replicates, in 630, 94 and 82 seed samples of B. brizantha, B. humidicola and P. maximum, respectively, tested at the Central Seed Testing Laboratory, Campinas, Brazil, from 1991 to 1999. Germination tests used two 4 x 100 replicates of intact and scarified seeds (15-, 10-, 5-minute treatments, respectively). Mean germination time (T50) and variability among germination replicates were also analysed. Statistical analysis was performed by t-test paired samples for means. Scarification promoted general decreases in T50, while variability among germination test replicates was reduced in B. brizantha. Scarification increase germination in B. brizantha and P. maximum, but is deleterious in B. humidicola.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Abstract The aim of this research project is to draw on accounts of experiences ofborder crossing and regulation at the Canada/U.S. border at Niagara in order to illuminate the dynamics of differentiation and inequality at this site. The research is informed by claims that the world is turning into a global village due to transnational flows oftechnology, infonnation, capital and people. Much of the available literature on globalization shows that while the transfer of technology, information, and capital are enhanced, the transnational movement of people is both facilitated and constrained in complex and unequal ways. In this project, the workings of facilitation and constraint were explored through an analysis often interviews with people who had spent a substantial portion oftheir childhood (e.g. 5 years) in a Canadian border community. The interviewees were at the time ofthe research between the ages of 19 and 25. Because most ofthe respondents were 'white' Canadians of working to upper middle class status, my focus was to explore how 'whiteness' as privilege may translate into enhanced movement across borders and how 'white' people may internalize and enjoy this privilege but may often deny its reality. I was also interested in how inequality is perceived, understood, and legitimated by these relatively privileged people. My analysis ofthe ten accounts ofborder crossing and regulation suggests that differentially situated people experience border crossing differently. An important finding is that while relatively privileged border crossers perceived and often problernatized differential treatment based on external factors such as physical appearance, and especially race, most did not challenge such treatment but rather saw it as acceptable. These findings are located within newer literature that addresses the increasing securitization ofborders and migration in western societies.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Qualitative spatial reasoning (QSR) is an important field of AI that deals with qualitative aspects of spatial entities. Regions and their relationships are described in qualitative terms instead of numerical values. This approach models human based reasoning about such entities closer than other approaches. Any relationships between regions that we encounter in our daily life situations are normally formulated in natural language. For example, one can outline one's room plan to an expert by indicating which rooms should be connected to each other. Mereotopology as an area of QSR combines mereology, topology and algebraic methods. As mereotopology plays an important role in region based theories of space, our focus is on one of the most widely referenced formalisms for QSR, the region connection calculus (RCC). RCC is a first order theory based on a primitive connectedness relation, which is a binary symmetric relation satisfying some additional properties. By using this relation we can define a set of basic binary relations which have the property of being jointly exhaustive and pairwise disjoint (JEPD), which means that between any two spatial entities exactly one of the basic relations hold. Basic reasoning can now be done by using the composition operation on relations whose results are stored in a composition table. Relation algebras (RAs) have become a main entity for spatial reasoning in the area of QSR. These algebras are based on equational reasoning which can be used to derive further relations between regions in a certain situation. Any of those algebras describe the relation between regions up to a certain degree of detail. In this thesis we will use the method of splitting atoms in a RA in order to reproduce known algebras such as RCC15 and RCC25 systematically and to generate new algebras, and hence a more detailed description of regions, beyond RCC25.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A media release from Inniskillin Wines announcing the launch of "Alliánce", a joint winemaking venture between Inniskillin and Jaffelin Wines of France.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A News Release draft to be sent to "100 newspapers, radio and television stations (virtually all those with offices within 20 miles of the Lakes), make them available to the Press Gallery, special interest groups, trade publication and Mayors etc. of Great Lake-side communities". The release discusses the need for an upgrade to "the 1972 Canada-U.S. Great Lakes Water Quality agreement". Within the document, O'Sullivan is quoted that the agreement "should be upgraded to become a treaty with the United States, so that after all the effort which has already been put into tyring to clean up the Great Lakes we the provision which provides for cancellation by either party giving twelve months (notice) to do so". The total report is 61 pages in length.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A press release from Youth for Diefenbaker, 1 August 1967. The release reads: "Hamilton Student Appointed Youth for Dief Representative. The youngest delegate to the conservative leadership convention, 15 year old Sean O'Sullivan of Hamilton, has been named Western Ontario representative of the Youth for Diefenbaker movement. This movement was formed in Ottawa to engage support of Canada's young conservatives for John Diefenbaker at the leadership convention. According to Mr. O'Sullivan, there is growing support for Mr. Diefenbaker and he will have an announcement to make in that regard at a press conference on Friday August Fourth at the Connaught Hotel."

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A press release assigning Sean O'Sullivan to study the future of the Great Lakes and St. Lawrence Seaway.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Indenture of release regarding a loan of 12, 500 pounds which Samuel Zimmerman (deceased) is said to have lent and advanced to the Woodstock and Lake Erie Railway and Harbour Company. This is put forward by the executors who include: Joseph A. Woodruff, Richard Woodruff, John L. Ranney and Richard Miller. This document releases and exonerates the Railway Company from any debts to the executors. [The outside of the document says 1857, but the actual date is Feb. 10, 1858].