344 research outputs found
Heat transfer coefficients from Newtonian and non-Newtonian fluids flowing in laminar regime in a helical coil
This study aimed to carry out experimental work to obtain, for Newtonian and non-Newtonian fluids, heat transfer coefficients, at constant wall temperature as boundary condition, in fully developed laminar flow inside a helical coil. The Newtonian fluids studied were aqueous solutions of glycerol, 25%, 36%, 43%, 59% and 78% (w/w) and the non-Newtonian fluids aqueous solutions of carboxymethylcellulose (CMC), a polymer, with concentrations 0.1%, 0.2%, 0.3%, 0.4% and 0.6% (w/w) and aqueous solutions of xanthan gum (XG), another polymer, with concentrations 0.1% and 0.2% (w/w). According to the rheological study performed, the polymer solutions had shear thinning behavior and different values of elasticity. The helical coil used has internal diameter, curvature ratio, length and pitch, respectively: 0.004575 m, 0.0263, 5.0 m and 11.34 mm. The Nusselt numbers for the CMC solutions are, on average, slightly higher than those for Newtonian fluids, for identical Prandtl and generalized Dean numbers. As outcome, the viscous component of the shear thinning polymer tends to potentiate the mixing effect of the Dean cells. The Nusselt numbers of the XG solutions are significant lower than those of the Newtonian solutions, for identical Prandtl and generalized Dean numbers. Therefore, the elastic component of the polymer tends to diminish the mixing effect of the Dean cells. A global correlation, for Nusselt number as a function of Péclet, generalized Dean and Weissenberg numbers for all Newtonian and non-Newtonian solutions studied, is presented
Friction losses of Newtonian and non-Newtonian fluids flowing in laminar regime in a helical coil
This study aimed to carry out experimental work to determine, for Newtonian and non-Newtonian fluids, the friction factor (fc) with simultaneous heat transfer, at constant wall temperature as boundary condition, in fully developed laminar flow inside a vertical helical coil. The Newtonian fluids studied were aqueous solutions of glycerol, 25%, 36%, 43%, 59% and 78% (w/w). The non-Newtonian fluids were aqueous solutions of carboxymethylcellulose (CMC), a polymer, with concentrations of 0.2%, 0.3%, 0.4% and 0.6% (w/w) and aqueous solutions of xanthan gum (XG), another polymer, with concentrations of 0.1% and 0.2% (w/w). According to the rheological study done, the polymer solutions had shear-thinning behavior and different values of viscoelasticity. The helical coil used has an internal diameter, curvature ratio, length and pitch, respectively: 0.00483 m, 0.0263, 5.0 m and 11.34 mm. It was concluded that the friction factors, with simultaneous heat transfer, for Newtonian fluids can be calculated using expressions from literature for isothermal flows. The friction factors for CMC and XG solutions are similar to those for Newtonian fluids when the Dean number, based in a generalized Reynolds number, is less than 80. For Dean numbers higher than 80, the friction factors of the CMC solutions are lower those of the XG solutions and of the Newtonian fluids. In this range the friction factors decrease with the increase of the viscometric component of the solution and increase for increasing elastic component. The change of behavior at Dean number 80, for Newtonian and non-Newtonian fluids, is in accordance with the study of Ali [4]. There is a change of behavior at Dean number 80, for Newtonian and non-Newtonian fluids, which is in according to previous studies. The data also showed that the use of the bulk temperature or of the film temperature to calculate the physical properties of the fluid has a residual effect in the friction factor values
Effectiveness of Interventions to Reduce Potentially Inappropriate Medication in Older Patients: A Systematic Review
Background: Age-related multiple comorbidities cause older adults to be prone to the use of potentially inappropriate medicines (PIM) resulting in an increased risk of adverse events. Several strategies have emerged to support PIM prescription, and a huge number of interventions to reduce PIM have been proposed. This work aims to analyze the effectiveness of PIM interventions directed to older adults. Methods: A systematic review was performed searching the literature in the MEDLINE PubMed, EMBASE, and Cochrane scientific databases for interventional studies that assessed the PIM interventions in older adults (≥65 years). Results: Forty-seven articles were included, involving 52 to 124,802 patients. Various types of interventions were analyzed such as medication review, educational strategies, clinical decision support system, and organizational and multifaceted approaches. In the hospital, the most successful intervention was medication review (75.0%), while in primary care, the analysis of all included studies revealed that educational strategies were the most effective. However, the analysis of interventions that have greater evidence by its design was inconclusive. Conclusion: The results obtained in this work suggested that PIM-setting-directed interventions should be developed to promote the wellbeing of the patients through PIM reduction. Although the data obtained suggested that medication review was the most assertive strategy to decrease the number of PIM in the hospital setting, more studies are necessary
Selection of Tumor-Specific Cytotoxic T Lymphocytes in Acute Myeloid Leukemia Patients Through the Identification of T-Cells Capable to Establish Stable Interactions With the Leukemic Cells: “Doublet Technology”
The relevance of the immune system in cancer has long been studied. Autologous adoptive T cell therapies, based on the use of tumor infiltrating lymphocytes (TILs), have made great progress in recent years for the treatment of solid tumors, especially melanoma. However, further work is needed to isolate tumor-reactive T cells among patients diagnosed with hematologic malignancies. The dynamics of the interaction between T cells and antigen presenting cells (APC) dictate the quality of the immune responses. While stable joints between target cells and T lymphocytes lead to the induction of T cell activation and immune response, brief contacts contribute to the induction of immune-tolerance. Taking advantage of the strong interaction between target cell and activated T-cells, we show the feasibility to identify and isolate tumor-specific cytotoxic T lymphocytes (CTLs) from acute myeloid leukemia (AML) patients by flow cytometry. Using this technology, CTLs bound through T cell receptor (TCR) to tumor cells can be identified in peripheral blood and bone marrow and subsequently selected and isolated by FACS-based cell sorting. These CTLs display higher percentage of effector cells and marked cytotoxic activity against AML blasts. In conclusion, we have developed a new procedure to identify and select specific cytotoxic T cells in patients diagnosed with acute myeloid leukemia.Instituto de Salud Carlos III PFIS-FI12/00189Instituto de Salud Carlos III ISCIII PI14/02074Instituto de Salud Carlos III PI11/02366Instituto de Salud Carlos III PI17/02177European Union (ERDF/ESF, Investing in your future)CIBER CB16/12/0048
Projeto sincronias : uma experiência de integração
Vários autores e entidades internacionais de referência têm determinado em documentos orientadores para os cuidados de psiquiatria e reabilitação psicossocial a pessoas com experiência de doença mental, a utilização de atividades artísticas como boa prática, já com alguma evidência, na promoção do recovery, participação social e qualidade de vida. O projeto Sincronias, resultante da parceria estabelecida entre a Associação Nova Aurora na Reabilitação e Reintegração Psicossocial (ANARP), a Escola Superior de Educação do Instituto Politécnico do Porto (ESE) e o Laboratório de Reabilitação Psicossocial da ESTSIPP/FPCEUP, tem precisamente como objetivo contribuir para o desenvolvimento pessoal e inserção social de pessoas com experiência de doença mental grave, através do seu envolvimento num programa de atividades artísticas personalizado, ajustado às necessidades e perfil dos seus participantes, que facilite a criatividade, a expressão e o crescimento pessoal através das artes.
O programa ocorrerá nas áreas da pintura, escultura, cerâmica, desenho, tipografia, entre outras e prevê o envolvimento dos participantes em iniciativas tão diversificadas como a sua integração nas unidades curriculares desenvolvidas na Licenciatura de Artes Visuais e Tecnologias Artísticas da ESE/IPP, a frequência de workshops/seminários promovidos quer nas instalações da ESE/IPP, quer na ANARP, e a organização e participação em exposições desenvolvidas em várias entidades culturais da cidade.info:eu-repo/semantics/publishedVersio
Sources and Chemistry of NOₓ in the Upper Troposphere Over the United States
The origin of NOx in the upper troposphere over the central United States is examined using aircraft observations obtained during the SUCCESS campaign in April–May of 1996. Correlations between NOy (sum of NOx and its oxidation products) and CO at 8–12 km altitude indicate that NOx originates primarily from convective transport of polluted boundary layer air. Lightning and aircraft emissions appear to be only minor sources of NOx. Chemical steady state model calculations constrained by local observations of NO underestimate the measured NOx/NOy concentration ratio at 8–12 km altitude by a factor of two on average. The magnitude of the underestimate is correlated with concentrations of condensation nuclei, which we take as a proxy for the age of air in the upper troposphere. We conclude that the NOx/NOy ratio is maintained above chemical steady state by frequent convective injections of fresh NOx from the polluted boundary layer and by the long lifetime of NOx in the upper troposphere (5–10 days). In contrast to previous studies, we find no evidence for fast heterogeneous recycling from HNO3 to NOx in the upper troposphere
Chromium (VI) ion adsorption features of chitosan film and its chitosan/zeolite conjugate 13X film
This research evaluated the importance of the adsorption properties of chitosan a chitosan/zeolite conjugate film for the removal of Cr(VI) ions from solutions in the 5–260 mg/L concentration range, when the pH was adjusted to 4.0 and 6.0. The uptake capacities of the films formed by chitosan and by the chitosan/zeolite conjugate were calculated by mass balance. The equilibrium isotherms were fitted to the Langmuir, Freundlich and Redlich-Peterson models. The chitosan film seems to be a good sorbent for Cr(VI) at pH 4, but its physical instability suggests the need for a more resilient support. Due to this fact zeolite was added to the chitosan matrix in solution and a chitosan/zeolite (CS/Zeo) film was thus formed. The solubility of the film and the characterization of the different matrices by FTIR, TGA and X-Ray showed that a cross-linked structure was formed between the chitosan and zeolite and the solubility of the film increased. In this study, the low manufacturing cost of the CS/Zeo matrix, the good uptake of Cr(VI) at acidic pH (17.28 mg/g) and the non desorption of Cr(VI) from the film in water suggests this combination should be tested in industrial environment.The authors are grateful for the Coordination of Improvement of Higher Education Personnel (CAPES - Brazil) for PhD fellowship and the financial support received from Financier of Studies and Projects (FINEP - Brazil), National Council for Scientific and Technological Development (CNPq - Brazil), Catholic University of Pernambuco (UNICAP - Brazil), University of Minho (UMINHO - Portugal). They also acknowledge Antonio Soares Vicente (UMINHO - Portugal) who kindly supplied the chitosan
Heterogeneous N2O5 Uptake During Winter: Aircraft Measurements During the 2015 WINTER Campaign and Critical Evaluation of Current Parameterizations
Nocturnal dinitrogen pentoxide (N2O5) heterogeneous chemistry impacts regional air quality and the distribution and lifetime of tropospheric oxidants. Formed from the oxidation of nitrogen oxides, N2O5 is heterogeneously lost to aerosol with a highly variable reaction probability, γ(N2O5), dependent on aerosol composition and ambient conditions. Reaction products include soluble nitrate (HNO3 or NO3−) and nitryl chloride (ClNO2). We report the first‐ever derivations of γ(N2O5) from ambient wintertime aircraft measurements in the critically important nocturnal residual boundary layer. Box modeling of the 2015 Wintertime INvestigation of Transport, Emissions, and Reactivity (WINTER) campaign over the eastern United States derived 2,876 individual γ(N2O5) values with a median value of 0.0143 and range of 2 × 10−5 to 0.1751. WINTER γ(N2O5) values exhibited the strongest correlation with aerosol water content, but weak correlations with other variables, such as aerosol nitrate and organics, suggesting a complex, nonlinear dependence on multiple factors, or an additional dependence on a nonobserved factor. This factor may be related to aerosol phase, morphology (i.e., core shell), or mixing state, none of which are commonly measured during aircraft field studies. Despite general agreement with previous laboratory observations, comparison of WINTER data with 14 literature parameterizations (used to predict γ(N2O5) in chemical transport models) confirms that none of the current methods reproduce the full range of γ(N2O5) values. Nine reproduce the WINTER median within a factor of 2. Presented here is the first field‐based, empirical parameterization of γ(N2O5), fit to WINTER data, based on the functional form of previous parameterizations
Three-month vs. one-year detraining effects after multicomponent exercise program in hypertensive older women
Background: Chronic diseases are the leading causes of death and disability in older
women. Physical exercise training programs promote beneficial effects for health and quality of life.
However, exercise interruption periods may be detrimental for the hemodynamic and lipidic profiles
of hypertensive older women with dyslipidemia. Methods: Nineteen hypertensive older women
with dyslipidemia (exercise group: 67.5 ± 5.4 years, 1.53 ± 3.42 m, 71.84 ± 7.45 kg) performed
a supervised multicomponent exercise training program (METP) during nine months, followed
by a one-year detraining period (DT), while fourteen hypertensive older women (control group:
66.4 ± 5.2 years, 1.56 ± 3.10 m, 69.38 ± 5.24 kg) with dyslipidemia kept their continued daily routine
without exercise. For both groups, hemodynamic and lipidic profiles and functional capacities (FCs)
were assessed four times: before and after the METP and after 3 and 12 months of DT (no exercise
was carried out). Results: The METP improved hemodynamic and lipidic profiles (p < 0.05), while
three months of DT decreased all (p < 0.05) parameters, with the exception of diastolic blood pressure
(DBP). One year of DT significantly (p < 0.01) decreased systolic blood pressure (7.85%), DBP (2.29%),
resting heart rate (7.95%), blood glucose (19.14%), total cholesterol (10.27%), triglycerides (6.92%)
and FC—agility (4.24%), lower- (−12.75%) and upper-body strength (−12.17%), cardiorespiratory
capacity (−4.81%) and lower- (−16.16%) and upper-body flexibility (−11.11%). Conclusion: Nine
months of the exercise program significantly improved the hemodynamic and lipid profiles as well
as the functional capacities of hypertensive older women with dyslipidemia. Although a detraining
period is detrimental to these benefits, it seems that the first three months are more prominent in
these alterations.info:eu-repo/semantics/publishedVersio
Assessment of online water-soluble brown carbon measuring systems for aircraft sampling
Brown carbon (BrC) consists of particulate organic species that preferentially absorb light at visible and ultraviolet wavelengths. Ambient studies show that as a component of aerosol particles, BrC affects photochemical reaction rates and regional to global climate. Some organic chromophores are especially toxic, linking BrC to adverse health effects. The lack of direct measurements of BrC has limited our understanding of its prevalence, sources, evolution, and impacts. We describe the first direct, online measurements of water-soluble BrC on research aircraft by three separate instruments. Each instrument measured light absorption over a broad wavelength range using a liquid waveguide capillary cell (LWCC) and grating spectrometer, with particles collected into water by a particle-into-liquid sampler (CSU PILS-LWCC and NOAA PILS-LWCC) or a mist chamber (MC-LWCC). The instruments were deployed on the NSF C-130 aircraft during WE-CAN 2018 as well as the NASA DC-8 and the NOAA Twin Otter aircraft during FIREX-AQ 2019, where they sampled fresh and moderately aged wildfire plumes. Here, we describe the instruments, calibrations, data analysis and corrections for baseline drift and hysteresis. Detection limits (3σ) at 365 nm were 1.53 Mm−1 (MC-LWCC; 2.5 min sampling time), 0.89 Mm−1 (CSU PILS-LWCC; 30 s sampling time), and 0.03 Mm−1 (NOAA PILS-LWCC; 30 s sampling time). Measurement uncertainties were 28 % (MC-LWCC), 12 % (CSU PILS-LWCC), and 11 % (NOAA PILS-LWCC). The MC-LWCC system agreed well with offline measurements from filter samples, with a slope of 0.91 and R2=0.89. Overall, these instruments provide soluble BrC measurements with specificity and geographical coverage that is unavailable by other methods, but their sensitivity and time resolution can be challenging for aircraft studies where large and rapid changes in BrC concentrations may be encountered
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