7 resultados para Aerosol Evolution, Nanoparticle Transformation, Busy Road, Statistical Analysis
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
PURPOSE: The infection is one of the main factors that affect the physiological evolution of the surgical wounds. The aim of this work is to evaluate the effects of fibroblast growth factor (FGFâ) and anti-FGFâ in the healing, synthesis and maturation of collagen when topically used on infected skin wounds of rats. METHODS: An experimental study was perfomed in 60 male Wistar rats. All animals were divided in two groups (A and B). Each group was divided in three subgroups A1, B1; A2, B2 and A3, B3. After anesthesia with pentobarbital, two open squared wounds (1cm2), 4cm distant to each other, were done in the dorsal skin of all the rats. In group A (n=30) the wounds were contaminated with multibacterial standard solution, and in group B(n=30) the wounds were maintained sterile. These wounds were named F1 (for inflammation analysis) and F2 (for collagen study). The open wounds of A1 and B1 rats were topically treated with saline solution, A2 and B2 were treated with FGFâ and subgroups A3 and B3 were treated with FGFâ and anti-FGFâ. The rats were observed until complete epitelization of F2 wounds for determination of healing time and the expression of types I and III collagen, using Picro Sirius Red staining. Inflammatory reaction in F1 wounds was studied using hematoxilineosin staining. The three variable was measured by the Image Pro-Plus Média Cybernetics software. The statistical analysis was performed by ANOVA and Tukey test, considering p<0.05 as significant. RESULTS: It was observed that infection retarded significantly (p<0.05) the time of wound scarring and the topical application of FCFb reverted the inhibition of healing caused by bacteria. The inflammatory reaction was greater in the subgroup B2 than in B1 and A3, and the difference was significant (p<0.05). It was observed greater expression of type I collagen in all the subgroups treated with FCFb, when compared with the untreated subgroups. Type III collagen was significantly decreased in wounds of B3 rats, comparing to the other subgroups. CONCLUSIONS: The FCFb accelerated the healing of open infected wounds and contributed with maturation of collagen, enhancing the type I collagen density. The anti-FCFb antibody was able to attenuate the production of both type I and III collagen
Resumo:
Discrepancies between classical model predictions and experimental data for deep bed filtration have been reported by various authors. In order to understand these discrepancies, an analytic continuum model for deep bed filtration is proposed. In this model, a filter coefficient is attributed to each distinct retention mechanism (straining, diffusion, gravity interception, etc.). It was shown that these coefficients generally cannot be merged into an effective filter coefficient, as considered in the classical model. Furthermore, the derived analytic solutions for the proposed model were applied for fitting experimental data, and a very good agreement between experimental data and proposed model predictions were obtained. Comparison of the obtained results with empirical correlations allowed identifying the dominant retention mechanisms. In addition, it was shown that the larger the ratio of particle to pore sizes, the more intensive the straining mechanism and the larger the discrepancies between experimental data and classical model predictions. The classical model and proposed model were compared via statistical analysis. The obtained p values allow concluding that the proposed model should be preferred especially when straining plays an important role. In addition, deep bed filtration with finite retention capacity was studied. This work also involves the study of filtration of particles through porous media with a finite capacity of filtration. It was observed, in this case, that is necessary to consider changes in the boundary conditions through time evolution. It was obtained a solution for such a model using different functions of filtration coefficients. Besides that, it was shown how to build a solution for any filtration coefficient. It was seen that, even considering the same filtration coefficient, the classic model and the one here propposed, show different predictions for the concentration of particles retained in the porous media and for the suspended particles at the exit of the media
Resumo:
Alcohol is one of the few psychotropic drugs that their consumption has admitted legally and sometimes encouraged by the society. Studies show alcohol as the highest consumption of drugs among young people and society in general, probably because of its availability and easy access. The abuse causes public health problems, which was closely related to the violence, socioeconomic problems and the high number of automobile accidents. Transit is one of the main sectors affected by the effects of alcohol, observing a high incidence in the studies. About half of automobile accidents occurs after the consumption of alcoholic beverage, and the vast majority of cases related to high concentrations of alcohol in the bloodstream. The relationship of drunk with traffic accidents is in fact evident everywhere in the world, including Brazil, where studies have shown a high relationship between alcohol consumption and traffic accidents. This study determined the alcohol in fatal victims of traffic accidents in the state of Rio Grande do Norte and established the profile of this population compared with those found in Brazil and other countries. Samples of blood of ethanol added to fulfillment of the standardization of chromatographic conditions and procedures for the analysis, being employed in the determination of alcohol in blood samples of 277 victims of traffic accidents, collected at the Institute of Scientific Technical Police of Rio Grande do North (ITEP) in the year 2007. The blood alcohol level was determined in these samples correlated with the sex, age and marital status of the victim and the location, day of week and month when the accident occurred, is doing a statistical analysis and outlining a profile of the victims of an accident at transit in the state of Rio Grande do Norte. The parameters of standardization studied ensured the quality of the analytical method and, consequently, to obtain reliable laboratory results. Being given the best temperature for injector (150 ºC), detector (250 ºC) and column (50 ºC) with a flow of gas in the column of 2mL/minutos and analysis of time of 12 minutes. The method was linear in the range of 0.01 to 3.2 g / L (r2 = 0.9989) with average recovery of 100.2% and precision with coefficient of variation less than 15%. The analysis carried out on victims of fatal road traffic accidents, ethanol detected in the blood in 66.43% of the victims and these, 96% showed concentration ≥ 0.2 g / L, 87.73% of victims were male, while 12.27% female. The younger age group (1535 years) was the most involved (52,35%) and most single (55.60%). The accidents occurred with greater prevalence in the day on Monday (27%) followed by Sunday (24,19%) and Saturday (15,52%) and it was found that the prevalence of injuries varied between the different months of the year, and in February (14.4%) and April (10.47%) the months that had a higher number of accidents, however this oscillation showed no statistically significant difference. Also no significant difference was observed between the tracks of concentration found in men and women. The standardized method showed to be efficient, given satisfactorily to the goals of this work, and the high levels of alcohol found in victims of fatal road traffic accidents are consistent with several studies of literature, and the profile of the victim also supported by presenting in its most young adults, male and single
Resumo:
Oral squamous cell carcinoma is the most common malignant neoplasm in oral cavity. Several studies have been carried out to establish biologic behaviour criteria of this neoplasm. Thus, the purpose of this experiment was to performe a clinic, morphologic and immunohistochemical analysis, by the expression of cytokeratins 7, 10, 13, 14, 16 and 19 in 30 cases of tongue squamous cell carcinoma from the files of Dr. Luiz Antônio Hospital (Natal-RN). It was verifeid of the immunoexpression the correlation clinic estadiament and histologic gradation system proposed by Bryne (1998), in order to investigate the use of these intermediate filaments as an indicator of tumour progression. Data was collected from the patients file and it was observed that information regarding sex, age and race was resemble to the literature. Data obtained from disease evolution, clinic estadiament, metastasis and expression of cytokeratins 7, 10, 13, 14, 16 and 19 was submited to statistical analysis (Test K2), which showed that only the histologic gradation didn t demonstrated significant correlation to the clinic variables. The expression the cytokeratins presented variation in the analysed tumours. CK 10 expression showed significant correlation to metastasis, and the presence of CK 16 was related to disease evolution (obit/remission) and also with the T3 and T4 of TNM. These results evidenced that metastasis and TNM showed a good efficacy as a prognostic indicator. The histologic gradation proposed by Bryne (1998) didn t reflect the biologic behaviour of the studied tongue squamous cell carcinoma, and the analysis of some intermediate filaments of cytokeratins seems to reflect the biologic behaviour and agressivity of some oral squamous cell carcinoma
Resumo:
The discovery of giant stars in the spectral regions G and K, showing moderate to rapid rotation and single behavior, namely with constant radial velocity, represents one important topic of study in Stellar Astrophysics. Indeed, such anomalous rotation clearly violates the theoretical predictions on the evolution of stellar rotation, since in evolved evolutionary stages is expected that the single stars essentially have low rotation due to the evolutionary expansion. This property is well-established from the observational point of view, with different studies showing that for single giant stars of spectral types G and K values of the rotation are typically smaller than 5kms−1 . This Thesis seeks an effective contribution to solving the paradigm described above, aiming to search for single stars of spectral types G and K with anomalous rotation, tipically rotation of moderate to rapid, in other luminosity classes. In this context, we analyzed a large stellar sample consisting of 2010 apparently single stars of luminosity classes IV, III, II and Ib with spectral types G and K, with rotational velocity v sin i and radial velocity measurements obtained from observations made by CORAVEL spectrometers. As a first result of impact we discovered the presence of anomalous rotators also among subgiants, bright giants and supergiants stars, namelly stars of luminosity classes IV, II and Ib, in contrast to previous studies, that reported anomalous rotators only in the luminosity class III classic giants. Such a finding of great significance because it allows us to analyze the presence of anomalous rotation at different intervals of mass, since the luminosity classes considered here cover a mass range between 0.80 and 20MJ, approximately. In the present survey we discovered 1 subgiant, 9 giants, 2 bright giants and 5 Ib supergiants, in spectral regions G and K, with values of v sin i ≥ 10kms−1 and single behavior. This amount of 17 stars corresponds to a frequency of 0.8% of G and K single evolved stars with anomalous rotation in the mentioned classes of luminosities, listed at the Bright Star Catalog, which is complete to visual magnitude 6.3. Given these new findings, based on a stellar sample complete in visual magnitude, as that of the Bright Star Catalog, we conducted a comparative statistical analysis using the Kolmogorov- Smirnov test, from where we conclude that the distributions of rotational velocity, v sin i, for single evolved stars with anomalous rotation in luminosity classes III and II, are similar to the distributions of v sin i for spectroscopic binary systems with evolved components with the same spectral type and luminosity class. This vii result indicates that the process of coalescence between stars of a binary system might be a possible mechanism to explain the observed abnormal rotation in the referred abnormal rotators, at least among the giants and bright giants, where the rotation in excess would be associated with the transfer of angular momentum for the star resulting from the merger. Another important result of this Thesis concerns the behavior of the infrared emission in most of the stars with anomalous rotation here studied, where 14 stars of the sample tend to have an excess in IR compared with single stars with low rotation, within of their luminosity class. This property represents an additional link in the search for the physical mechanisms responsible for the abnormal observed rotation, since recent theoretical studies show that the accretion of objects of sub-stellar mass, such as brown dwarfs and giant planets, by the hosting star, can significantly raise its rotation, producing also a circumstellar dust disk. This last result seems to point in that direction, since it is not expected that dust disks occurring during the stage of star formation can survive until the stages of subgiants, giants and supergiants Ib. In summary, in this Thesis, besides the discovery of single G and K evolved stars of luminosity classes IV, II and Ib with anomalously high rotation compared to what is predicted by stellar evolution theory, we also present the frequency of these abnormal rotators in a stellar sample complete to visual magnitude 6.3. We also present solid evidence that coalescence processes in stellar binary systems and processes of accretion of brown dwarfs star or giant planets, by the hosting stars, can act as mechanisms responsible for the puzzling phenomenon of anomalous rotation in single evolved stars.
Resumo:
PURPOSE: The infection is one of the main factors that affect the physiological evolution of the surgical wounds. The aim of this work is to evaluate the effects of fibroblast growth factor (FGFâ) and anti-FGFâ in the healing, synthesis and maturation of collagen when topically used on infected skin wounds of rats. METHODS: An experimental study was perfomed in 60 male Wistar rats. All animals were divided in two groups (A and B). Each group was divided in three subgroups A1, B1; A2, B2 and A3, B3. After anesthesia with pentobarbital, two open squared wounds (1cm2), 4cm distant to each other, were done in the dorsal skin of all the rats. In group A (n=30) the wounds were contaminated with multibacterial standard solution, and in group B(n=30) the wounds were maintained sterile. These wounds were named F1 (for inflammation analysis) and F2 (for collagen study). The open wounds of A1 and B1 rats were topically treated with saline solution, A2 and B2 were treated with FGFâ and subgroups A3 and B3 were treated with FGFâ and anti-FGFâ. The rats were observed until complete epitelization of F2 wounds for determination of healing time and the expression of types I and III collagen, using Picro Sirius Red staining. Inflammatory reaction in F1 wounds was studied using hematoxilineosin staining. The three variable was measured by the Image Pro-Plus Média Cybernetics software. The statistical analysis was performed by ANOVA and Tukey test, considering p<0.05 as significant. RESULTS: It was observed that infection retarded significantly (p<0.05) the time of wound scarring and the topical application of FCFb reverted the inhibition of healing caused by bacteria. The inflammatory reaction was greater in the subgroup B2 than in B1 and A3, and the difference was significant (p<0.05). It was observed greater expression of type I collagen in all the subgroups treated with FCFb, when compared with the untreated subgroups. Type III collagen was significantly decreased in wounds of B3 rats, comparing to the other subgroups. CONCLUSIONS: The FCFb accelerated the healing of open infected wounds and contributed with maturation of collagen, enhancing the type I collagen density. The anti-FCFb antibody was able to attenuate the production of both type I and III collagen
Resumo:
Discrepancies between classical model predictions and experimental data for deep bed filtration have been reported by various authors. In order to understand these discrepancies, an analytic continuum model for deep bed filtration is proposed. In this model, a filter coefficient is attributed to each distinct retention mechanism (straining, diffusion, gravity interception, etc.). It was shown that these coefficients generally cannot be merged into an effective filter coefficient, as considered in the classical model. Furthermore, the derived analytic solutions for the proposed model were applied for fitting experimental data, and a very good agreement between experimental data and proposed model predictions were obtained. Comparison of the obtained results with empirical correlations allowed identifying the dominant retention mechanisms. In addition, it was shown that the larger the ratio of particle to pore sizes, the more intensive the straining mechanism and the larger the discrepancies between experimental data and classical model predictions. The classical model and proposed model were compared via statistical analysis. The obtained p values allow concluding that the proposed model should be preferred especially when straining plays an important role. In addition, deep bed filtration with finite retention capacity was studied. This work also involves the study of filtration of particles through porous media with a finite capacity of filtration. It was observed, in this case, that is necessary to consider changes in the boundary conditions through time evolution. It was obtained a solution for such a model using different functions of filtration coefficients. Besides that, it was shown how to build a solution for any filtration coefficient. It was seen that, even considering the same filtration coefficient, the classic model and the one here propposed, show different predictions for the concentration of particles retained in the porous media and for the suspended particles at the exit of the media
