971 resultados para HEAT-SHOCK PROTEINS
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At head of title: Cornell University, Graduate School of Aeronautical Engineering.
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Mode of access: Internet.
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The textures of yogurt made from ultra-high temperature (UHT) treated and conventionally treated milks at high total solids were investigated. The yogurt premixes, fortified with low-heat skim milk powder to 16%, 18%, and 20% total solids, were UHT processed at 143 degreesC for 6 s and heated at 85 degreesC for 30 min using the conventional method. The onset of gelation was delayed in the UHT-processed milk compared with conventionally heated milk. During fermentation, the viscosity of yogurt made, from UHT-treated milk at 20% total solids was close to that of yogurt made from conventionally treated milk with 16% total solids. However, after storage for greater than or equal to1 d, the yogurt made from UHT-treated milk had lower viscosity and gel strength than the yogurt made from conventionally treated milk. The solids level had no influence on yogurt culture growth.
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The properties of commercial directly and indirectly heated UHT milks, both after heating and during storage at room temperature for 24 weeks, were studied. Thermally induced changes were examined by changes in lactulose, furosine and acid-soluble whey proteins. The results confirmed previous reports that directly heated UHT milks suffer less heat damage than indirectly heated milk. During storage, furosine increased and bovine serum albumin in directly heat-treated milks decreased significantly. The changes in lactulose, alpha-lactalbumin and beta-lactoglobulin were not statistically significant. The data suggest that heat treatment indicators should be measured as soon as possible after processing to avoid any misinterpretations of the intensity of the heat treatment.
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Results of the benchmark test are presented of comparing numerical schemes solving shock wave of M-s = 2.38 in nitrogen and argon interacting with a 43 degrees semi-apex angle cone and corresponding experiments. The benchmark test was announced in Shock Waves Vol. 12, No. 4, in which we tried to clarify the effects of viscosity and heat conductivity on shock reflection in conical flows. This paper summarizes results of ten numerical and two experimental applications. State of the art in studies regarding the shock/cone interaction is clarified.
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Lift, pitching moment, and thrust/drag on a supersonic combustion ramjet were measured in the T4 free-piston shock tunnel using a three-component stress-wave force balance. The scramjet model was 0.567 m long and weighed approximately 6 kg. Combustion occurred at a nozzle-supply enthalpy of 3.3 MJ/kg and nozzle-supply pressure of 32 MPa at Mach 6.6 for equivalence ratios up to 1.4. The force coefficients varied approximately linearly with equivalence ratio. The location of the center of pressure changed by 10% of the chord of the model over the range of equivalence ratios tested. Lift and pitching-moment coefficients remained constant when the nozzle-supply enthalpy was increased to 4.9 MJ/kg at an equivalence ratio of 0.8, but the thrust coefficient decreased rapidly. When the nozzle-supply pressure was reduced at a nozzle-supply enthalpy of 3.3 MJ/kg and an equivalence ratio of 0.8, the combustion-generated increment of lift and thrust was maintained at 26 MPa, but disappeared at 16 MPa. Measured lift and thrust forces agreed well with calculations made using a simplified force prediction model, but the measured pitching moment substantially exceeded predictions. Choking occurred at nozzle-supply enthalpies of less than 3.0 MJ/kg with an equivalence ratio of 0.8. The tests failed to yield a positive thrust because of the skin-friction drag that accounted for up to 50% of the fuel-off drag.
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The effectiveness of rapid and controlled heating of intact tissue to inactivate native enzymatic activity and prevent proteome degradation has been evaluated. Mouse brains were bisected immediately following excision, with one hemisphere being heat treated followed by snap freezing in liquid nitrogen while the other hemisphere was snap frozen immediately. Sections were cut by cryostatic microtome and analyzed by MALDI-MS imaging and minimal label 2-D DIGE, to monitor time-dependent relative changes in intensities of protein and peptide signals. Analysis by MALDI-MS imaging demonstrated that the relative intensities of markers varied across a time course (0-5 min) when the tissues were not stabilized by heat treatment. However, the same markers were seen to be stabilized when the tissues were heat treated before snap freezing. Intensity profiles for proteins indicative of both degradation and stabilization were generated when samples of treated and nontreated tissues were analyzed by 2-D DIGE, with protein extracted before and after a 10-min warming of samples. Thus, heat treatment of tissues at the time of excision is shown to prevent subsequent uncontrolled degradation of tissues at the proteomic level before any quantitative analysis, and to be compatible with downstream proteomic analysis.
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This work represents ongoing efforts to study high-enthalpy carbon dioxide flows in anticipation of the upcoming Mars Science Laboratory (MSL) and future missions to the red planet. The work is motivated by observed anomalies between experimental and numerical studies in hypervelocity impulse facilities for high enthalpy carbon dioxide flows. In this work, experiments are conducted in the Hypervelocity Expansion Tube (HET) which, by virtue of its flow acceleration process, exhibits minimal freestream dissociation in comparison to reflected shock tunnels. This simplifies the comparison with computational result as freestream dissociation and considerable thermochemical excitation can be neglected. Shock shapes of the MSL aeroshell and spherical geometries are compared with numerical simulations incorporating detailed CO2 thermochemical modeling. The shock stand-off distance has been identified in the past as sensitive to the thermochemical state and as such, is used here as an experimental measurable for comparison with CFD and two different theoretical models. It is seen that models based upon binary scaling assumptions are not applicable for the low-density, small-scale conditions of the current work. Mars Science Laboratory shock shapes at zero angle of attack are also in good agreement with available data from the LENS X expansion tunnel facility, confi rming results are facility-independent for the same type of flow acceleration, and indicating that the flow velocity is a suitable first-order matching parameter for comparative testing. In an e ffort to address surface chemistry issues arising from high-enthalpy carbon dioxide ground-test based experiments, spherical stagnation point and aeroshell heat transfer distributions are also compared with simulation. Very good agreement between experiment and CFD is seen for all shock shapes and heat transfer distributions fall within the non-catalytic and super-catalytic solutions. We also examine spatial temperature profiles in the non-equilibrium relaxation region behind a stationary shock wave in a hypervelocity air Mach 7.42 freestream. The normal shock wave is established through a Mach reflection from an opposing wedge arrangement. Schlieren images confirm that the shock con guration is steady and the location is repeatable. Emission spectroscopy is used to identify dissociated species and to make vibrational temperature measurements using both the nitric oxide and the hydroxyl radical A-X band sequences. Temperature measurements are presented at selected locations behind the normal shock. LIFBASE is used as the simulation spectrum software for OH temperature-fitting, however the need to access higher vibrational and rotational levels for NO leads to the use of an in-house developed algorithm. For NO, results demonstrate the contribution of higher vibrational and rotational levels to the spectra at the conditions of this study. Very good agreement is achieved between the experimentally measured NO vibrational temperatures and calculations performed using an existing state-resolved, three-dimensional forced harmonic oscillator thermochemical model. The measured NO A-X vibrational temperatures are significantly higher than the OH A-X temperatures.
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Fish is a valuable nutritional source witch use of it in daily meal has a beneficial role on nutritional needs supply and also causes mental and physical health especially in people who have protein and food deficiencies. Unfortunately, per capita consumption of sea foods in Iran is 5.5Kg witch is very lower than world standards. So, study on fish ice cream formulation, by use of fish protein concentrate (FPC) instead of milk protein, had done to make variation in sea foods products and also increase per capita consumption of these kinds of foods. FPC has very high protein concentration and a lot of necessary Also it's protein is very digestible amino acids like lysine and methionine with highly biological value and it's PER in compare with casein PER is high. At first fish protein concentrate type A produced from silver carp in three steps by the extraction with isopropyl alcohol solvent and heat. Microbiological and physicochemical specifications of produced FPC by rules of FDA and FAO were accepted. Finally according to panel test results, substitution of 30 percent of milk with FPC is acceptable. Also microbiological and physicochemical specifications of product were tested and results in compare with national standards of Iran were accepted.
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The main objective of the research is to demonstrate new physiological characteristics receptors in the presence of mosquito larvae. 100 larvae of different species were collected and studied for a week in periods of 8-24 hrs. Larvae stages I, II, III and IV have photo-thermo receptors of light and heat housed in the body is divided into head, thorax and abdomen, perceive hot or cold environments, and have fibers in chest or hairs lining your body or abdomen, and a pair of antennae on the head. Stages II and III are more developed than the initial stages. They are attracted by the dark green at the bottom, a pair of eyes that perceive light and color. Have receptors proteins (RP55) that capture motion at a speed the slightest movement of waves in the water. Its nose is not well developed but have chemoreceptors. They adapt to changes in pH in alkaline media, are sensitive to chemical, thermal and mechanical changes nociceptors have electroreceptors or galvanoreceptores sensitive to electrical stimuli, have mechanoreceptors that are sensitive to touch, pain, pressure, gravity, sound. They have a GPS position that seems the guides. It is precisely in the fibers, mushrooms or bristles are recipients along with the micro villi in head, thorax and abdomen.
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El objetivo principal de la investigación es demostrar nuevas características fisiológicas como la presencia de receptores en las larvas de mosquitos. Se recolectaron 100 larvas de diferentes especies y se estudiaron por una semana en periodos de 8 a 24 hrs. Las larvas de los estadios I,II,III y IV tienen foto-termo receptores de luz y calor alojados en el cuerpo que se divide en cabeza, tórax y abdomen, perciben ambientes fríos o calientes, así como tienen fibras en tórax o pelos que recubren su cuerpo, y un par de antenas en la cabeza. Los estadios II y III son más desarrollados que las etapas iniciales. Tienen receptores proteicos RP55. Les atrae el color verde oscuro en el fondo, un par de ojos que perciben la luz y color con fotoreceptores. Tienen receptores RP55 de movimiento que captan a una velocidad el más mínimo movimiento de ondas en el agua. Su olfato no está muy desarrollado pero tienen quimioreceptores. Se adaptan a cambios de pH en medios alcalinos, tienen nociceptores sensibles a cambios químicos, térmicos y mecánicos, tienen galvanoreceptores o electroreceptores sensibles a estímulos eléctricos, tienen mecanoreceptores que son sensibles al tacto, dolor, presión gravedad, sonido. Tienen un GPS de posición que pareciera las orienta.
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Tuberculosis (TB) remains a pandemic affecting billions of people worldwide, thus stressing the need for new vaccines. Defining the correlates of vaccine protection is essential to achieve this goal. In this study, we used the wild boar model for mycobacterial infection and TB to characterize the protective mechanisms elicited by a new heat inactivated Mycobacterium bovis vaccine (IV). Oral vaccination with the IV resulted in significantly lower culture and lesion scores, particularly in the thorax, suggesting that the IV might provide a novel vaccine for TB control with special impact on the prevention of pulmonary disease, which is one of the limitations of current vaccines. Oral vaccination with the IV induced an adaptive antibody response and activation of the innate immune response including the complement component C3 and inflammasome. Mycobacterial DNA/RNA was not involved in inflammasome activation but increased C3 production by a still unknown mechanism. The results also suggested a protective mechanism mediated by the activation of IFN-γ producing CD8+ T cells by MHC I antigen presenting dendritic cells (DCs) in response to vaccination with the IV, without a clear role for Th1 CD4+ T cells. These results support a role for DCs in triggering the immune response to the IV through a mechanism similar to the phagocyte response to PAMPs with a central role for C3 in protection against mycobacterial infection. Higher C3 levels may allow increased opsonophagocytosis and effective bacterial clearance, while interfering with CR3-mediated opsonic and nonopsonic phagocytosis of mycobacteria, a process that could be enhanced by specific antibodies against mycobacterial proteins induced by vaccination with the IV. These results suggest that the IV acts through novel mechanisms to protect against TB in wild boar.
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Soil salinity affects rhizobia both as free-living bacteria and in symbiosis with the host. The aim of this study was to examine the transcriptional response of the Lotus microsymbiont Mesorhizobium loti MAFF303099 to salt shock. Changes in the transcriptome of bacterial cells subjected to a salt shock of 10% NaCl for 30 min were analyzed. From a total of 7231 protein-coding genes, 385 were found to be differentially expressed upon salt shock, among which 272 were overexpressed. Although a large number of overexpressed genes encode hypothetical proteins, the two most frequently represented COG categories are "defense mechanisms" and "nucleotide transport and metabolism". A significant number of transcriptional regulators and ABC transporters genes were upregulated. Chemotaxis and motility genes were not differentially expressed. Moreover, most genes previously reported to be involved in salt tolerance were not differentially expressed. The transcriptional response to salt shock of a rhizobium with low ability to grow under salinity conditions, but enduring a salinity shock, may enlighten us concerning salinity stress response mechanisms.
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Button battery ingestion is a frequent pediatric complaint. The serious complications resulting from accidental ingestion have increased significantly over the last two decades due to easy access to gadgets and electronic toys. Over recent years, the increasing use of lithium batteries of diameter 20 mm has brought new challenges, because these are more detrimental to the mucosa, compared with other types, with high morbidity and mortality. The clinical complaints, which are often nonspecific, may lead to delayed diagnosis, thereby increasing the risk of severe complications. A five-year-old boy who had been complaining of abdominal pain for ten days, was brought to the emergency service with a clinical condition of hematemesis that started two hours earlier. On admission, he presented pallor, tachycardia and hypotension. A plain abdominal x-ray produced an image suggestive of a button battery. Digestive endoscopy showed a deep ulcerated lesion in the esophagus without active bleeding. After this procedure, the patient presented profuse hematemesis and severe hypotension, followed by cardiorespiratory arrest, which was reversed. He then underwent emergency exploratory laparotomy and presented a new episode of cardiorespiratory arrest, which he did not survive. The battery was removed through rectal exploration. This case describes a fatal evolution of button battery ingestion with late diagnosis and severe associated injury of the digestive mucosa. A high level of clinical suspicion is essential for preventing this evolution. Preventive strategies are required, as well as health education, with warnings to parents, caregivers and healthcare professionals.
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Xanthomonas citri subsp. citri (X. citri) is the causative agent of the citrus canker, a disease that affects several citrus plants in Brazil and across the world. Although many studies have demonstrated the importance of genes for infection and pathogenesis in this bacterium, there are no data related to phosphate uptake and assimilation pathways. To identify the proteins that are involved in the phosphate response, we performed a proteomic analysis of X. citri extracts after growth in three culture media with different phosphate concentrations. Using mass spectrometry and bioinformatics analysis, we showed that X. citri conserved orthologous genes from Pho regulon in Escherichia coli, including the two-component system PhoR/PhoB, ATP binding cassette (ABC transporter) Pst for phosphate uptake, and the alkaline phosphatase PhoA. Analysis performed under phosphate starvation provided evidence of the relevance of the Pst system for phosphate uptake, as well as both periplasmic binding proteins, PhoX and PstS, which were formed in high abundance. The results from this study are the first evidence of the Pho regulon activation in X. citri and bring new insights for studies related to the bacterial metabolism and physiology. Biological significance Using proteomics and bioinformatics analysis we showed for the first time that the phytopathogenic bacterium X. citri conserves a set of proteins that belong to the Pho regulon, which are induced during phosphate starvation. The most relevant in terms of conservation and up-regulation were the periplasmic-binding proteins PstS and PhoX from the ABC transporter PstSBAC for phosphate, the two-component system composed by PhoR/PhoB and the alkaline phosphatase PhoA.
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Understanding the molecular mechanisms of oral carcinogenesis will yield important advances in diagnostics, prognostics, effective treatment, and outcome of oral cancer. Hence, in this study we have investigated the proteomic and peptidomic profiles by combining an orthotopic murine model of oral squamous cell carcinoma (OSCC), mass spectrometry-based proteomics and biological network analysis. Our results indicated the up-regulation of proteins involved in actin cytoskeleton organization and cell-cell junction assembly events and their expression was validated in human OSCC tissues. In addition, the functional relevance of talin-1 in OSCC adhesion, migration and invasion was demonstrated. Taken together, this study identified specific processes deregulated in oral cancer and provided novel refined OSCC-targeting molecules.