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1.
Heliyon ; 10(10): e30188, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38803878

RESUMO

The current investigation delves into the convective heat and mass transfer characteristics of third-grade radiative nanofluid flow within a porous medium over a Riga plate configuration. The Riga plate structure incorporates magnets and electrodes strategically arranged on a plate surface. To enhance the accuracy of energy and concentration expressions within the third-grade fluid flow, the Cattano Christov Double Diffusion model is employed. Entropy generation analysis is conducted by applying the second law of thermodynamics, and Darcy's model is employed to characterize the behavior of a porous medium. Appropriate similarity transformations have been used to convert the partial differential equations monitoring the fluid flow model into dimensionless ordinary differential equations. The Galerkin weighted residual method is employed to resolve these equations numerically. The findings contain detailed explanations of how relevant factors affect the temperature field, concentration field, velocity field, entropy generation, and Bejan number, in addition to graphic representations of the results. The findings indicate that the medium's porosity and Brinkman number promote entropy generation. The Bejan number and entropy production is affected by the thermal radiation parameter, which first rises and then declines after a certain distance.

2.
Comput Biol Med ; 176: 108617, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38772055

RESUMO

In the modern era, the utilization of electro-kinetic-driven microfluidic pumping procedures spans various biomedical and physiological domains. The present study introduces a mathematical framework for characterizing the hemodynamics of peristaltic blood flow within a porous tube infused with ZrO2 nanoparticles. This model delves into the interactions between buoyancy, electro-osmotic forces, and aggregated nanoparticles to discern their influence on blood flow. We employ a third-grade fluid model to elucidate the rheological behavior of the pseudoplastic fluid which refers to its response to applied shear stress, specifically the relationship between shear rate and viscosity. The collective influence of accommodating heat convection, joule heating and aggregated nanoparticles contributes to the thermal behavior of fluids. The distribution of electric potential within the electric double layer (EDL) is predicted by solving the Poisson-Boltzmann equation. The rescaled equations are simplified using the lubrication and Debye-Hückel models as the underlying frameworks. The novel homotopy perturbation method is employed to obtain solutions for the finalized non-linear partial differential equation. Theoretical assessment of hemodynamic impacts involves plotting graphical configurations for various emerging parameters. As electro-osmotic parameter increase, the bloodstream encounters greater impedance, thereby enhancing the effectiveness of electro-osmotic assistance. Concurrently, elevated convective heat markedly reduces the rate of heat transfer, potentially resulting in a drop in blood temperature. It is important to note that maximum shear stress occurs when the artery is positioned horizontally, underscoring the significant impact of arterial alignment on wall shear stress. Skin friction intensifies with the increasing wall permeability as aggregated nanofluids pass through the arterial conduit. Therefore, aggregation of nanoparticles into the bloodstream yields a broader spectrum of distinctive physiological features. In summary, these findings enable more effective tool and device designs for addressing medication administration challenges and electro-therapies.


Assuntos
Nanopartículas , Nanopartículas/química , Humanos , Porosidade , Eletro-Osmose , Peristaltismo/fisiologia , Osmose , Zircônio/química
3.
Heliyon ; 9(5): e16192, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37229170

RESUMO

In this study, an analysis was performed to investigate the thermal and mass transport of radiative flow of a third-grade nanofluid with magnetohydrodynamic. The analysis concerns two-dimensional flow around an infinite disk. Heat transport is studied via heat generation/absorption, thermal radiation and Joule heating. Chemical reaction with activation energy is also considered. The nanofluid characteristics, including Brownian motion and thermophoretic diffusion, are explored via the Buongiorno model. Entropy analysis is also conducted. Moreover, the surface tension is assumed to be a linear function of concentration and temperature. Through adequate dimensionless variables, governed PDEs are non-dimensionlized and then tackled by ND-solve (a numerical method in Mathematica) for solutions purposes. Entropy generation, concentration, velocity, Bejan number and temperature are plotted as functions of the involved physical parameters. It is noticed that higher Marangoni number intensify velocity however it causes a decrease in the temperature. Entropy rate and Bejan number boost for large value of diffusion parameter.

4.
Pediatr Cardiol ; 44(2): 472-478, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36454266

RESUMO

Children with congenital heart defects (CHDs) are at risk for poor academic performance. The degree to which receipt of health care services is associated with adverse academic outcomes is not known. We examined the association between episodes of cardiac care and third-grade performance in children with CHD. We identified subjects between 1/1/2008 and 4/30/2012 among 5 centers in North Carolina. We classified children by CHD type and linked subjects to the state educational records. Any inpatient or outpatient cardiac encounter on a date of service was considered an encounter. We calculated the number of encounters by adding the number of inpatient or outpatient cardiac visits prior to the date of the end-of-grade (EOG) tests. We estimated the odds of failing third-grade reading or math EOG tests by episodes of care stratified at the 50th percentile, controlling for CHD type, maternal education, sex, race/ethnicity, birth weight, and gestational age. A total of 184 children had third-grade EOG scores linked to health care records. The median number of episodes of care was 4 (range: 1-60). Those with visits ˃ 50th percentile (> 4 encounters/year over the 4.3 year observation period) had 2.09 (95% CI 1.04, 4.21) greater odds of failing the math EOG compared to those ≤ 50th percentile (1-4 encounters). The third-grade math score declined by 1.5 points (P < 0.008) for every 10 episodes of care. There was no association of episodes of care on third-grade reading performance. Children with CHD with > 4 episodes of cardiac care/year may be at risk for delays in third-grade academic performance. Strategies to minimize school absenteeism may improve academic success in this population.


Assuntos
Desempenho Acadêmico , Cardiopatias Congênitas , Humanos , Criança , Escolaridade , Cardiopatias Congênitas/epidemiologia , Cardiopatias Congênitas/terapia , Instituições Acadêmicas , North Carolina/epidemiologia
5.
Arab J Sci Eng ; 47(6): 7505-7518, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34603928

RESUMO

In the present study, modeling of intelligent numerical computing through Levenberg-Marquardt back propagation-based supervised neural network (LMB-SNN) is incorporated to analyze the magnetohydrodynamic flow of a third grade fluid for wire coating analysis (MHD-TGFWCA). The original mathematical formulations in terms of partial differential equations for MHD-TGFWCA are converted into a system of ordinary differential equations through dimensionless parameters and a suitable transformation mechanism. A reference dataset for the LMB-SNNs scheme is created with Adam's numerical technique for various scenarios by variation of different physical quantities such as third grade fluid parameter, magnetic parameter, and the velocity ratio parameter. To compute the approximate solution for MHD-TGFWCA in terms of various scenarios, the training, testing, and validation operations are carried out in parallel to adjust neural networks by developing the mean square error function (MSEF) through Levenberg-Marquardt back-propagation. The comparative analyses and performance studies through outputs of MSEF, regression illustrations, and error histograms validate the effectiveness of the suggested solver LMB-SNNs. The method's precision is verified by the closest numerical outputs of both built and dataset values with similar levels 10 - 5 to 10 - 9 .

6.
J Biol Phys ; 47(4): 499-520, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34618313

RESUMO

As part of the growing evolution in nanotechnology and thermal sciences, nanoparticles are considered as an alternative solution for the energy depletion due to their ultra-high thermal effectives. Nanofluids reflect inclusive and broad-spectrum significances in engineering, industrial and bio-engineering like power plants, energy source, air conditioning systems, surface coatings, evaporators, power consumptions, nano-medicine, cancer treatment, etc. The present study describes the bio-convective peristaltic flow of a third-grade nanofluid in a tapered asymmetric channel. Basic conservation laws of mass, momentum, energy, and concentration as well as the microorganism diffusion equation are utilized to model the problem. The simplified form of the modeled expressions is accounted with long wavelength assumptions. For solving the resulting coupled and nonlinear equations, a well-known numerical method implicit finite difference scheme has been utilized. The graphical results describe the velocity, temperature and concentration profiles, and the density of motile microorganisms at the nanoscale. Furthermore, microorganism concentration lines are analyzed.


Assuntos
Nanopartículas , Peristaltismo , Movimento (Física) , Temperatura
7.
Heliyon ; 6(5): e03621, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32478180

RESUMO

In this present study, the impacts of magnetic field and thermal radiation on squeezing flow and heat transfer of third grade nanofluid between two disks embedded in a porous medium with temperature jump boundary conditions is analyzed using differential transformation method. The results of the approximate analytical solutions are verified using a fifth-order Runge-Kutta Fehlberg method (Cash-Karp Runge-Kutta) coupled with shooting method. From the analysis, the results of the two methods show excellent agreements. Also, the parametric studies using the approximate analytical solutions show that for a suction parameter greater than zero, the radial velocity of the lower disc increases while that of the upper disc decreases as a result of a corresponding increase in the viscosity of the fluid from the lower squeezing disc to the upper disc. For an increasing magnetic field parameter, the radial velocity of the lower disc decreases while that of the upper disc increases. As the third grade fluid parameter increases, there is a reduction in the fluid viscosity thereby increasing resistance between the fluid molecules. Also, it is found that as the radiation parameter increases, rate of heat transfer to the third grade fluid increases. There is a recorded decrease in the fluid temperature profile as the Prandtl number increases due to decrease in the thermal diffusivity of the third grade fluid. The agreement of the results of the present study and the experimental work shows the validation of the models used in this work to study the flow behaviour of the fluid. It is envisaged that the present work will increase the understanding of the flow behaviour of third grade nanofluid and heat transfer processes as evident in coal slurries, polymer solutions, textiles, ceramics, catalytic reactors, oil recovery applications etc.

8.
Micromachines (Basel) ; 11(4)2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32316085

RESUMO

The present paper discusses the electromagnetohydrodynamic (EMHD) electroosmotic flow (EOF) and entropy generation of incompressible third-grade fluids in a parallel microchannel. Numerical solutions of the non-homogeneous partial differential equations of velocity and temperature are obtained by the Chebyshev spectral collocation method. The effects of non-Newtonian parameter Λ, Hartman number Ha and Brinkman number Br on the velocity, temperature, Nusselt number and entropy generation are analyzed in detail and shown graphically. The main results show that both temperature and Nusselt number decrease with the non-Newtonian physical parameter, while the local and total entropy generation rates exhibit an adverse trend, which means that non-Newtonian parameter can provoke the local entropy generation rate. In addition, we also find that the increase of non-Newtonian parameter can lead to the increase of the critical Hartman number Hac.

9.
Materials (Basel) ; 12(19)2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31547183

RESUMO

Wire coatings are necessary to provide protection from the aggressive environment and to add mechanical strength to wires and cables. In this study, we investigated the effect of radiative linear as well as non-linear heat transfer on the wire coating in response to joule heating, using a third grade fluid as the coating material. For the temperature dependent viscosity, two models namely-Reynolds' and Vogel's-were used. The non-linear ordinary differential equations were solved analytically by the Homotropy Analysis Method (HAM). Numerical technique was also applied for comparison and good agreement was found. It is interesting to note that the temperature parameter had a remarkable effect on the temperature distribution and heat transfer characteristics in the flow region within the die. It was observed that the velocity of the fluid within the die decreased as the magnetic parameter increased, while the magnetic field had an accelerating effect on the temperature distribution. Near the surface of the wire, the velocity of the coating material accelerated as the temperature parameter and radiation parameter increased. Analysis also showed that the temperature of the coating material decreased with increasing radiation and temperature parameters.

10.
Child Youth Serv Rev ; 101: 285-298, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31213731

RESUMO

Although substantial investments in early childhood intervention have continued, whether gains are sustained past kindergarten for routinely implemented programs is a critical research need. Using data from the Chicago Longitudinal Study (CLS; N=1,539; 50.3% female; 92.9% African American and 7.1% Hispanic), an on-going investigation of the Child-Parent Center (CPC) program for an inner-city cohort, this study investigates the effects of program duration from preschool to 3rd grade on school outcomes and whether the effects differ by gender. Regression analyses are conducted to compare the differences in outcomes among intervention groups. Inverse probability weighting (IPW) is used to adjust for potential attrition and selection biases. Findings indicate that relative to the preschool plus kindergarten (P-K) group, participation from preschool through third grade (P-3) is significantly associated with better academic functioning at both 3rd and 8th grades, better classroom adjustment at 3rd grade, lower rates of retention and school mobility, and few years of special education. Relative to the preschool through second grade (P-2) group, the P-3 group has significantly higher academic functioning in third grade. Results suggest that the P-3 dosage is associated with larger effects on academic functioning for girls and larger effects on social-emotional functioning for boys compare to the P-K dosage. Findings suggest that receiving up to third grade (P-3) of an early childhood education program have associated with persistent effects on developmental outcomes compared to the dosages of P-K. Multi-year programs have the potential to sustain early childhood gains and promote healthy development via improving academic functioning and school experiences.

11.
Biomech Model Mechanobiol ; 17(1): 71-86, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28785830

RESUMO

In this paper, the heat and flow characteristic of third-grade non-Newtonian biofluids flow through a vertical porous human vessel due to peristaltic wall motion are studied. The third-grade model can describe shear thinning (or shear thickening) and normal stress differences, which is acceptable for biofluids modeling. In order to solve the governing equations, the assumption of long-wavelength approximation is utilized. This hypothesis emphasizes that the wavelength of the peristaltic wall motion is large in comparison with the radius of the human vessel, which is widely acceptable in biological investigations. The analytical perturbation method is employed to solve the governing equations. Consequently, analytical expressions for the velocity profile, shear stress, temperature field, and biofluid flow rate are obtained. In addition, the effects of the governing parameters such as the third-grade non-Newtonian parameter, Grashof Number, Eckert number, and porosity, on the results are examined.


Assuntos
Líquidos Corporais/fisiologia , Modelos Biológicos , Peristaltismo/fisiologia , Reologia , Temperatura Alta , Humanos , Porosidade , Pressão , Reprodutibilidade dos Testes , Estresse Mecânico
12.
China Pharmacy ; (12): 478-483, 2018.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-704609

RESUMO

OBJECTIVE: To analyze carbapenemases genotype of imipenem-resistant Gram-negative bacilli in intensive care unit (ICU) of 3 third grade class A hospitals from Qingdao area, so as to provide reference for drug-resistant bacteria infection prevention and treatment in clinic. METHODS: From Jan. 2013 to Jun. 2016, each 60 strains of imipenem-resistant Klebsiella pneumoniae (IRKP), imipenem-resistant Pseudomonas aeruginosa (IRPA) and imipenem-resistant Acinetobacter baumanii (IRAB) were collected from 3 third grade class A hospitals from Qingdao area. Drug sensitivity test was performed by using Kirby-Bauer method. Phenotypes of carbapenemases were determined by Carba NP trial. PCR was applied to amplify carbapenemase gene; Sanger seqnencing method was adopted for bi-directional sequencing; Blast comparison with GenBank database was conducted. RESULTS: Three kinds of imipenem-resistant Gram-negative bacilli showed high drug resistance to majority commonly used antibiotics as piperacillin, cefazolin, imipenem and cilastatin sodium, gentamicin, etc., but were sensitive to polymyxin B (resistance rate of 0). Among 180 drug-resistant strains, there were 52 strains of class A carbapenems, 13 strains of class B carbapenems and 39 strains of class D carbapenems; the detection rates of them were 28. 89%, 7. 22% and 21. 67%, respectively. There were 52 strains of KPC-2 gene (IRKP), 4 strains of IMP-1 gene (IRPA), 8 strains of VIM-2 gene (7 strains of IRPA, 1 strain of IRAB), 39 strains of OXA-23 gene (IRAB); the detection rates of them were 28. 89%, 2. 22%, 4. 44%, 21. 67%; all strains were not detected 1MP-2, VIM-1, NDM-1, OXA-24, OXA-58 genes. Results of Blast comparison showed that above detected genes were absolutely homology with the corresponding genes in GenBank database. CONCLUSIONS: Drug resistance of imipenem-resistant Gram-negative bacilli in ICU of 3 third grade class A hospitals is serious in this region, which are nearly no-sensitive to most of commonly used antibiotics in clinic. Main genotypes included KPC-2 (K. pneumoniae), OXA-23 (A. baumanii) and IMP-1 and VIM-2 (P. aeruginosa).

13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-658982

RESUMO

Up to 2015, almost all of the Third-grade class-A TCM hospitals in Beijing set up multiple sub-hospitals, under the regional integrating of Beijing-Tianjin-Hebei region, in order to meet regional homogenization of medical and health care demand, to provide high-quality medical service for the patients, and to improve the hospital development in a certain stage. Taking Beijing university of traditional Chinese medicine affiliated Dongfang hospital for example, it creates "two sub-hospitals " a court layout of mode of "one hospital with multiple branches". This article analyzed the sub-hospitals organization structure reform, cost budget control, performance management & personnel training, information system construction, to draw lessons from practical manage experience, and explored the "multiple sub-hospitals " superior management mode for our hospital.

14.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-661900

RESUMO

Up to 2015, almost all of the Third-grade class-A TCM hospitals in Beijing set up multiple sub-hospitals, under the regional integrating of Beijing-Tianjin-Hebei region, in order to meet regional homogenization of medical and health care demand, to provide high-quality medical service for the patients, and to improve the hospital development in a certain stage. Taking Beijing university of traditional Chinese medicine affiliated Dongfang hospital for example, it creates "two sub-hospitals " a court layout of mode of "one hospital with multiple branches". This article analyzed the sub-hospitals organization structure reform, cost budget control, performance management & personnel training, information system construction, to draw lessons from practical manage experience, and explored the "multiple sub-hospitals " superior management mode for our hospital.

15.
Chongqing Medicine ; (36): 3226-3228, 2017.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-610723

RESUMO

Objective To observe the turnaround time(TAT) of biochemistry laboratory in a certain hospital of Chongqing city,and to improve the quality of the laboratory by shortening the TAT.Methods TAT was analyzed by analyzing the daily workload,average TAT and failure rate of outpatient clinics,outpatient emergency,inpatient clinics,and inpatient emergency subjects from 2013 to 2015.The reasons for TAT prolongation were analyzed.Results The biochemical test samples were 77 060,97 129 and 105 304 from 2013 to 2015,and the annual growth rate was 26.0% and 8.4% respectively.TAT of the routine outpatient department samples were (78.55nu48.47)、(69.18± 37.20)、(62.82 ±21.62)min,which decreased year by year,and the difference were statistically significant(P<0.05),and the TAT of the outpatient emergency were (64.13 ± 31.16),(59.22 ± 23.51),(66.01±37.73)min.TAT of inpatient clinics were (92.34± 53.41),(95.03±55.73) and (122.92±78.94)min from 2013 to 2015,which increased year by year,and the difference were statistically significant(P<0.05),and the TAT of the inpatient emergency were(65.29±36.06),(62.41±30.18),(61.48±30.12)min,which decreased year by year,and the difference were statistically significant (P<0.05).The substandard rate of samples aforementioned were 0.04%,2.99%,0.63% and 3.69%,respectively.Conclusion TAT increases with the samples increase,it is necessary that making sure staffs more responsible in daily work,optimizing the procedure of daily biochemistry tests,improving ability of serving for clinic and patients.

16.
China Pharmacy ; (12): 2884-2889, 2017.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-617697

RESUMO

OBJECTIVE:To provide reference for formulating the policy of promoting the popularization and application of es-sential medicines in second grade or third grade medical institutions. METHODS:Drug purchase and warehousing data was collect-ed from 31 second grade or third grade medicinal institutions in Nanjing during Jan. 2012-Dec. 2015. Excel 2010 and SPSS 20.0 software were used to summarize and analyze statistically the purchase amount of allocation quantity of essential medicines. RE-SULTS:The proportion of essential medicine purchase amount in total medicine purchase amount during 2012-2015 were 18.33%, 18.56%,17.19%,17.53% in 31 medicinal institutions (calledthe ratio of essential medicine purchase amountfor short);the proportion of national essential medicine purchase amount in essential medicine purchase amount(calledthe ratio of essential medi-cine purchase amountfor short)were 31.14%,29.40%,25.69%,25.79%,respectively. The number of generic names for allocat-ed essential medicines were 189.84,205.58,210.26,206.65,respectively. The ratio of essential medicine purchase amount and the ratio of essential medicine purchase amount in 2014 were decreased significantly,compared to in 2013(P<0.05). The number of generic names for allocated essential medicines in 2013 was increased significantly,compared to in 2012 (P<0.05). The ratio of essential medicine purchase amount in second grade medical institutions was significantly higher than third grade medical institu-tions,the ratio of essential medicine purchase amount in general hospital was significantly higher than special hospital;the number of generic names for allocated essential medicines was significantly higher than TCM hospital and special hospital;the ratio of es-sential medicine purchase amount in second grade medical institutions with community health service center in subjection to them was significantly higher than those without community health service center in subjection to them;there was statistical significance (P<0.05). There was negative correlation between the ratio of essential medicine purchase and total purchase amount of medicine in general hospitals(P<0.05). There was positive correlation between the number of generic name of allocated essential medicines and the number of generic name of all medicines in 31 medical institutions(P<0.05). CONCLUSIONS:The ratio of essential med-icine purchase amount and national essential medicine purchase amount,the numbers of generic names of essential medicines were very different and low in these hospitals during 2012-2015. Just one or two had met the requirements of the Jiangsu provincial health and family planning commission. The grade,type,medicine purchase and allocation scale,administering community health service center all influence the purchase and allocation of essential medicines.

17.
Front Psychol ; 7: 825, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27378961

RESUMO

Although it has been proposed that inhibition is related to individual differences in mathematical achievement, it is not clear how it is related to specific aspects of mathematical skills, such as arithmetic fact retrieval. The present study therefore investigated the association between inhibition and arithmetic fact retrieval and further examined the unique role of inhibition in individual differences in arithmetic fact retrieval, in addition to numerical magnitude processing. We administered measures of cognitive inhibition (i.e., numerical and non-numerical stroop tasks) and a complementary, more ecologically valid measure of children's inhibition in the classroom (i.e., teacher questionnaire), as well as numerical magnitude processing (i.e., symbolic and non-symbolic numerical magnitude comparison) and arithmetic fact retrieval (i.e., two verification tasks) in 86 typically developing third graders. We used a correlation, a regression and a Bayesian analysis. This study failed to observe a significant association between inhibition and arithmetic fact retrieval. Consequently, our results did not reveal a unique contribution of inhibition to arithmetic fact retrieval in addition to numerical magnitude processing. On the other hand, symbolic numerical magnitude processing turned out to be a very powerful predictor of arithmetic fact retrieval, as indicated by both frequentist and Bayesian approaches.

18.
Biomed Mater Eng ; 27(1): 15-28, 2016 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-27175464

RESUMO

In this paper, magneto-hydrodynamic blood flows through porous arteries are numerically simulated using a locally modified homogenous nanofluids model. Blood is taken into account as the third-grade non-Newtonian fluid containing nanoparticles. In the modified nanofluids model, the viscosity, density, and thermal conductivity of the solid-liquid mixture (nanofluids) which are commonly utilized as an effective value, are locally combined with the prevalent single-phase model. The modified governing equations are solved numerically using Newton's method and a block tridiagonal matrix solver. The results are compared to the prevalent nanofluids single-phase model. In addition, the efficacies of important physical parameters such as pressure gradient, Brownian motion parameter, thermophoresis parameter, magnetic-field parameter, porosity parameter, and etc. on temperature, velocity and nanoparticles concentration profiles are examined.


Assuntos
Artérias/fisiologia , Hemorreologia , Simulação por Computador , Humanos , Hidrodinâmica , Campos Magnéticos , Modelos Cardiovasculares , Porosidade , Termodinâmica
19.
Comput Methods Programs Biomed ; 126: 3-19, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26792174

RESUMO

In this paper, the unsteady pulsatile magneto-hydrodynamic blood flows through porous arteries concerning the influence of externally imposed periodic body acceleration and a periodic pressure gradient are numerically simulated. Blood is taken into account as the third-grade non-Newtonian fluid. Besides the numerical solution, for small Womersley parameter (such as blood flow through arterioles and capillaries), the analytical perturbation method is used to solve the nonlinear governing equations. Consequently, analytical expressions for the velocity profile, wall shear stress, and blood flow rate are obtained. Excellent agreement between the analytical and numerical predictions is evident. Also, the effects of body acceleration, magnetic field, third-grade non-Newtonian parameter, pressure gradient, and porosity on the flow behaviors are examined. Some important conclusions are that, when the Womersley parameter is low, viscous forces tend to dominate the flow, velocity profiles are parabolic in shape, and the center-line velocity oscillates in phase with the driving pressure gradient. In addition, by increasing the pressure gradient, the mean value of the velocity profile increases and the amplitude of the velocity remains constant. Also, when non-Newtonian effect increases, the amplitude of the velocity profile.


Assuntos
Artérias/fisiologia , Vasos Sanguíneos/fisiologia , Sistema Cardiovascular , Hidrodinâmica , Modelos Cardiovasculares , Fluxo Pulsátil , Aceleração , Algoritmos , Velocidade do Fluxo Sanguíneo/fisiologia , Simulação por Computador , Humanos , Campos Magnéticos , Movimento , Oscilometria , Porosidade , Pressão , Reprodutibilidade dos Testes , Resistência ao Cisalhamento , Estresse Mecânico , Viscosidade
20.
China Pharmacy ; (12): 2887-2889, 2016.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-504719

RESUMO

OBJECTIVE:To provide reference for improving the service quality of outpatient pharmacy in hospital. METH-ODS:A questionnaire survey was conducted to investigate and analyze the patients’satisfaction and related influential factors to outpatient pharmacy in a third grade class-A hospital in Chengdu. RESULTS:Totally 165 questionnaires were sent out,and 150 were effectively received with effective recovery of 90.91%. The total score for patients’satisfaction was (44.67 ± 7.81) scores, and the rate of satisfaction was(81.22±14.19)%. The top three entries were“the will you choose to come to our hospital again if necessary”,“the notices about time and place for taking the medicine”and“the overall evaluation of the professional ethics of med-ical staff”,scored 4.38,4.25 and 4.25,respectively;the last three entries were“waiting time for taking medicine”,“the notices about how long it takes to take the medicine”and“service facilities and environmental facilities for drug taking”,scored 3.55, 3.63 and 3.95,respectively. The top three suggestions were“long waiting time for taking medicine and inconvenient”,“noisy envi-ronment,bad order”and“expensive drugs charges but less reimburse”. The univariate analysis and multivariate analysis showed that gender,age,marital status,education,occupation,family income per month,resident,drug taking times and payment etc. factors showed no significant effects on patients’satisfaction scores(P>0.05). CONCLUSIONS:The degree of patients’satisfac-tion in outpatient pharmacy have no obvious specificity and preference,the key to improve the degree of satisfaction lies on strengthening the service of the hospital and the perception of the patients. While the next research will focus on how to find the breakthrough points and key points to improve the experience of waiting,standardize process management and logistics manage-ment,and make patients aware of the service development.

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