108 resultados para Modified mass in hot-dense medium


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The objective of this work is to investigate the production of fatty acid ethyl esters from soybean oil in compressed propane using a non-commercial lipase from Yarrowia lipolytica and two commercial ones as catalysts, Amano PS and Amano AY30. The experiments were performed in the temperature range of 35-65 °C. at 50 bar, enzyme concentration of 5 wt%, oil to ethanol molar ratio of 1:6 and 1:9, and solvent to substrates mass ratio of 2:1 and 4:1. The results indicated that low reaction conversions were generally obtained with the use of commercial and non-commercial lipases in pressurized propane medium. On the other hand, the aspects of low solvent to substrates mass ratio and mild temperature and pressure operating conditions used to produce ethyl esters justify further investigations to improve reaction yields.

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The conversion of p-coumaric acid, ferulic acid, and caffeic acid into 4-ethylphenol, 4-ethylguaiacol and 4-ethylcatechol was studied in Dekkera bruxellensis ISA 1791 under defined conditions in a synthetic medium and in a red wine. Liquid chromatography (HPLC-DAD) was used to quantify the phenolic acids, and gas chromatography (GC) coupled to a FID detector was used to quantify volatile phenols using a novel analytical methodology that does not require sample derivatization. Identification was achieved by gas chromatography-mass detection (GC-MS). The results show that phenolic acids concentration decreases while volatile phenols concentration increases. The proportion of caffeic acid taken up by Dekkera bruxellensis is lower than that for p-coumaric or ferulic acid; therefore less 4-ethylcatechol is formed. More important, 4-ethylcathecol synthesis by Dekkera bruxellensis in wine has never been demonstrated so far. These results contribute decisively to a better understanding of the origin of the volatile phenols in wines. The accumulation of these compounds in wine is nowadays regarded as one of the key factors of quality control.

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SUMMARY The natural co-infection with dengue virus can occur in highly endemic areas where different serotypes have been observed for many years. We report one case of DENV-1/DENV-4 co-infection in human serum detected by molecular tests. Phylogenetic analysis of the sequences obtained indicated the presence of genotype V and II for DENV-1 and DENV-4, respectively.

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Attempts have been made to characterize two strains of Leishmania that became infective to golden hamsters only after they had been maintained for several years in a chemically defined culture medium. Observations were made on the growth rates of promastigotes in vitro, course of infection in hamsters, morphology of amastigotes, and electrophoretic mobility patterns of eight isoenzymes. Information was obtained about the buoyant densities of n-DNA and k-DNA, and one strain was tested against monoclonal antibodies. The identity of both strains remains obscure.

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The electrochemical reduction of p-nitrobenzenesulfonyl chloride (NBSCl) in dimethylsulfoxide (DMSO) solution is used here as a model to investigate the role of sulfinic acid derivative in this compound's global reduction process. Cyclic voltammetric experiments reveal the production of sulfinic acid derivative, which is important in chemical reactions involving the original compound and other intermediates. This paper also discusses the probable mechanisms of the reduction.

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This study aims to analyze the impacts of the reservoir network within Pereira de Miranda - CE catchment (also called Pentecoste) over sediment transport and storage capacity of the system. The survey of the "damming" was carried out using satellite images. We identified 502 erosion units, derived from overlaying maps of the Universal Soil Loss Equation parameters, which allowed the estimation of localized erosion in the basin and identification of areas potentially generating sediment. In order to estimate silting in Pentecoste reservoir, different system structure scenarios were considered. An average erosion rate of 59 t ha-1year-1 was estimated. According to the model, the silting of Pentecoste reservoir may vary from 1.1 to 2.6% per decade, depending on the scenario considered. It is also observed that the reservoirs upstream can retain up to 58% of the sediment that would reach the Pentecoste reservoir. Very small reservoirs with a capacity of up to 100,000 m³, although representing only 1.83% of the system water availability, are able to retain almost 8% of total sediment produced.

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PURPOSE: To evaluate whether climacteric women undergoing liver transplantation had higher prevalence of decreased bone mass than those without any liver disease. METHODS: A cross-sectional study with 48 women receiving follow-up care at a university hospital in Southeastern Brazil, from February 4th 2009 to January 5th 2011, was conducted. Of these women, 24 were 35 years or older and had undergone liver transplantation at least one year before study entry. The remaining 24 women had no liver disease and their ages and menstrual patterns were similar to those of transplanted patients. Laboratorial tests (follicle-stimulating hormone and estradiol) and bone density measurements of the lumbar spine and femur (equipment Hologic, Discovery WI) were performed. Statistical analysis was carried out by Fisher's exact test, simple Odds Ratio (OR), and multiple logistic regression. RESULTS: Mean age of the women included in the study was 52.8 (±10.7) years-old, 27.1% were premenopausal and 72.9% were peri/postmenopausal. Approximately 14.6% of these women exhibited osteoporosis and 35.4% had low bone mass. The following items were associated with decreased bone mass: being postmenopausal (OR=71.4; 95%CI 3.8 - 1,339.7; p<0.0001), current age over 49 years-old (OR=11.4; 95%CI 2.9 - 44.0; p=0.0002), and serum estradiol levels lower than 44.5 pg/mL (OR=18.3; 95%CI 3.4 - 97.0; p<0.0001). Having a history of liver transplantation was not associated with decreased bone mass (OR=1.4; 95%CI 0.4 - 4.3; p=0.56). CONCLUSION: Liver transplantation was not associated with decreased bone mass in this group of climacteric women.

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Of all malignant neoplasias affecting women, breast cancer has the highest incidence rate in Brazil. The objective of the present study was to determine the frequency of genetic modifications in families with medium and high risk for breast and ovarian cancer from different regions of Brazil. An exploratory, descriptive study was carried out on the prevalence of the BRCA1 and BRCA2 mutations in case series of high-risk families for breast and/or ovarian cancer. After heredogram construction, a blood sample was taken and DNA extraction was performed in all index cases. The protein truncation test was used to screen for truncated mutations in exon 11 of the BRCA1 gene and in exons 10 and 11 of the BRCA2 gene. Of the 612 individuals submitted to genetic testing, 21 (3.4%), 19 women and 2 men, had mutations in the BRCA1 or BRCA2 genes. Of the 19 BRCA1 mutations found in the 18 participants, 7 consisted of ins6kb mutations, 4 were 5382insC, 3 were 2156delGinsCC, 2 were 185delAG, 1 was C1201G, 1 was C3522T, and 1 was 3450del4. With respect to the BRCA2 gene, 3 mutations were found: 5878del10, 5036delA and 4232insA (one case each). The prevalence of germline mutations in the BRCA1 and BRCA2 genes found in the present study was lower than reported by other studies on high-risk Brazilian populations. The inclusion of individuals with medium risk may have contributed to the lower prevalence observed.

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PCR-based technique for GMO detection is the most reliable choice because of its high sensitivity and specificity. As a candidate of the European Union, Turkey must comply with the rules for launching into the market, traceability, and labeling of GMOs as established by EU legislation. Therefore, the objective of this study is to assess soybean products in the Turkish market to verify compliance with legislation using qualitative Polymerase Chain Reaction (PCR) assay to detect the presence of GM soybean and to quantify its amount of GM soybean in the samples tested positive using real-time PCR. DNA extracted by the modified CTAB method was properly used for PCR amplification of food materials. The amplification of a 118 bp DNA fragment of the lectin gene from soybean by PCR was successfully achieved in all samples. The GMO screening was based on the detection of 35S promoter and NOS terminator sequences. The GM positive samples were subjected to detection of Roundup ReadyTM soybean (RR) using quantitative real-time PCR. It was found that 100% of the tested food samples contained less than 0.1 per cent of EPSPS gene.

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The difficulty on identifying, lack of segregation systems and absence of suitable standards for coexistence of non trangenic and transgenic soybean are contributing for contaminations that occur during productive system. The objective of this study was to evaluate the efficiency of two methods for detecting mixtures of seeds genetically modified (GM) into samples of non-GM soybean, in a way that seed lots can be assessed within the standards established by seed legislation. Two sizes of soybean samples (200 and 400 seeds), cv. BRSMG 810C (non-GM) and BRSMG 850GRR (GM), were assessed with four contamination levels (addition of GM seeds, for obtaining 0.0%, 0.5%, 1.0%, and 1.5% contamination), and two detection methods: immunoassay of lateral flux (ILF) and bioassay (pre-imbibition into 0.6% herbicide solution; 25 ºC; 16 h). The bioassay is efficient in detecting presence of GM seeds in seed samples of non-GM soybean, even for contamination lower than 1.0%, provided that seeds have high physiological quality. The ILF was positive, detecting the presence of target protein in contaminated samples, indicating test effectiveness. There was significant correlation between the two detection methods (r = 0.82; p < 0.0001). Sample size did not influence efficiency of the two methods in detecting presence of GM seeds.

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Individuals with systemic arterial hypertension have a higher risk of heat-related complications. Thus, the aim of this study was to examine the thermoregulatory responses of hypertensive subjects during recovery from moderate-intensity exercise performed in the heat. A total of eight essential hypertensive (H) and eight normotensive (N) male subjects (age=46.5±1.3 and 45.6±1.4 years, body mass index=25.8±0.8 and 25.6±0.6 kg/m2, mean arterial pressure=98.0±2.8 and 86.0±2.3 mmHg, respectively) rested for 30 min, performed 1 h of treadmill exercise at 50% of maximal oxygen consumption, and rested for 1 h after exercise in an environmental chamber at 38°C and 60% relative humidity. Skin and core temperatures were measured to calculate heat exchange parameters. Mean arterial pressure was higher in the hypertensive than in the normotensive subjects throughout the experiment (P<0.05, unpaired t-test). The hypertensive subjects stored less heat (H=-24.23±3.99 W·m−2vs N=-13.63±2.24 W·m−2, P=0.03, unpaired t-test), experienced greater variations in body temperature (H=-0.62±0.05°C vsN=-0.35±0.12°C, P=0.03, unpaired t-test), and had more evaporated sweat (H=-106.1±4.59 W·m−2vs N=-91.15±3.24 W·m−2, P=0.01, unpaired t-test) than the normotensive subjects during the period of recovery from exercise. In conclusion, essential hypertensive subjects showed greater sweat evaporation and increased heat dissipation and body cooling relative to normotensive subjects during recovery from moderate-intensity exercise performed in hot conditions.

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Halotolerant or halophilic (Archaeabacteria) microorganisms can be found in salted and ripening fish products that are not affected by salt. They can be moderate or extremely halophilic bacteria. The extremely halophilic bacteria require between 15-30% of NaCl for growth. The extremely halophilic archaeobacteria may be selectively isolated in different media. The aim of this work was to determine the effectiveness of the Salt-Agar-Milk medium, a medium modified in our laboratory through the addition of MgSO4 and KCl - named SAMm, and its effect on the bacterial growth by means of comparison with other media, with and without milk, determining time of incubation and counting. Two samples of salted fish from local fish salting factories and two laboratory strains were used. The factory samples were matured anchovy and anchovy fillets in oil, and the laboratory strains were: Haloarcula spp. (proteolytic) and Halococcus spp. (non-proteolytic). The following media were alternatively used for the isolation of extremely halophilic bacteria: IRAM; Formulation of Gibbons and collaborators, Cod Milk agar, and SAMm. IRAM and Gibbons were also used enriched with milk. In the SAMm medium, there were obtained count values similar or higher than the ones of the traditional media; besides the simplicity of its elaboration, the possibility to obtain positive results two or three days earlier also added to its benefit. Consequently, it can be considered an alternative to the media traditionally used for the studied halophilic bacteria.

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AbstractThis study aimed to evaluate the effect of the distillation time and the sample mass on the total SO2 content in integral passion fruit juice (Passiflora sp). For the SO2 analysis, a modified version of the Monier-Williams method was used. In this experiment, the distillation time and the sample mass were reduced to half of the values proposed in the original method. The analyses were performed in triplicate for each distilling time x sample mass binomial, making a total of 12 tests, which were performed on the same day. The significance of the effects of the different distillation times and sample mass were evaluated by applying one-factor analysis of variance (ANOVA). For a 95% confidence limit, it was found that the proposed amendments to the distillation time, sample mass, and the interaction between distilling time x sample mass were not significant (p > 0.05) in determining the SO2 content in passion fruit juice. In view of the results that were obtained it was concluded that for integral passion fruit juice it was possible to reduce the distillation time and the sample mass in determining the SO2 content by the Monier-Williams method without affecting the result.

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The objective of this study was to differentiate benign ovarian tumors from malignant ones before surgery using color and pulsed Doppler sonography, and to compare results obtained before and after use of contrast medium, thereby verifying whether contrast results in an improvement in the diagnostic sensitivity. METHODS: Sixty two women (mean age 49.9 years) with ovarian tumors were studied, 45 with benign and 17 with malignant tumors. All women underwent a transvaginal color Doppler ultrasonographic exam. A study of the arterial vascular flow was made in all tumor areas, as well as an impedance evaluation of arterial vascular flow using the resistance index. RESULT: Localization of the vessels in the tumor revealed a greater proportion of malignant tumors with detectable internal vascular flows (64%) than benign tumors with such flows (22%). There was a considerable overlap of these findings. The use of contrast identified a greater number of vessels with confirmation in the totality of tumors, but did not improve the Doppler capacity in tumoral differentiation. Malignant tumors presented lower values of resistance index than the benign ones, whether or not contrast was used. The cutoff value for resistance index that better maximized the Doppler sensitivity and specificity was 0.55. Through this value, an increase of the sensitivity after contrast use was obtained, varying from 47% to 82%, while specificity remained statistically unchanged. CONCLUSION: Although the injection of a microbubble agent improved the sensitivity of the method detecting vascularization of tumors, a positive finding for vascularization by this method was not clinically useful in the differentiation of benign and malignant ovarian tumors.

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Little is known about the molecular mechanisms underlying the release of merozoites from malaria infected erythrocytes. In this study membranous structures present in the culture medium at the time of merozoite release have been characterized. Biochemical and ultrastructural evidence indicate that membranous structures consist of the infected erythrocyte membrane, the parasitophorous vacuolar membrane and a residual body containing electron dense material. These are subcellular compartments expected in a structure that arises as a consequence of merozoite release from the infected cell. Ultrastructural studies show that a novel structure extends from the former parasite compartment to the surface membrane. Since these membrane modifications are detected only after merozoites have been released from the infected erythrocyte, it is proposed that they might play a role in the release of merozoites from the host cell