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1.
Sci Rep ; 13(1): 21039, 2023 Nov 29.
Article in English | MEDLINE | ID: mdl-38052878

ABSTRACT

This study explores the impacts of heat transportation on hybrid (Ag + MgO) nanofluid flow in a porous cavity using artificial neural networks (Bayesian regularization approach (BRT-ANN) neural networks technique). The cavity considered in this analysis is a semicircular shape with a heated and a cooled wall. The dynamics of flow and energy transmission in the cavity are influenced by various features such as the effect of magnetize field, porosity and volume fraction of nanoparticles. To explore the outcomes of these features on hybrid nanofluid thermal and flow transport, a BRT-ANN model is developed. The ANN model is trained using a dataset generated through numerical scheme. The trained ANN model is then used to predict the heat and flow transport characteristics for various input parameters. The accuracy of the ANN simulation is confirmed through comparison of the predicted results with the results obtained through numerical simulations. By maintaining the corrugated wall uniformly heated, we inspected the levels of isotherms, streamlines and heat transfer distribution. A graphical illustration highlights the characteristics of the Hartmann and Rayleigh numbers, permeability component in porous material, drag force and rate of energy transport. According to the percentage analysis, nanofluids (Ag + MgO/H2O) are prominent to enhance the thermal distribution of traditional fluids. The study demonstrates the potential of ANNs in predicting the impacts of various factors on hybrid nanofluid flow and heat transport, which can be useful in designing and optimizing heat transfer systems.

2.
Vaccine ; 41(48): 7220-7225, 2023 11 22.
Article in English | MEDLINE | ID: mdl-37884416

ABSTRACT

Rotavirus vaccines have substantially decreased rotavirus hospitalizations in countries where they have been implemented. In some high- and middle-income countries, a low-level of increased risk of intussusception, a type of acute bowel obstruction, has been detected following rotavirus vaccination. However, no increased risk of intussusception was found in India, South Africa, or a network of 7 other African countries. We assessed the association between a 2-dose monovalent rotavirus vaccine (Rotarix) and intussusception in 3 early-adopter low-income Asian countries -- Afghanistan, Myanmar, and Pakistan. Children <12 months of age admitted to a sentinel surveillance hospital with Brighton level 1 intussusception were eligible for enrollment. We collected information about each child's vaccination status and used the self-controlled case series method to calculate the relative incidence of intussusception 1-7 days, 8-21 days, and 1-21 days following each dose of vaccine and derived confidence intervals with bootstrapping. Of the 585 children meeting the analytic criteria, the median age at intussusception symptom onset was 24 weeks (IQR: 19-29). Overall, 494 (84 %) children received the first Rotarix dose and 398 (68 %) received the second dose. There was no increased intussusception risk during any of the risk periods following the first (1-7 days: 1.01 (95 %CI: 0.39, 2.60); 8-21 days: 1.37 (95 %CI: 0.81, 2.32); 1-21 days: 1.28 (95 %CI: 0.78, 2.11)) or second (1-7 days: 0.81 (95 %CI: 0.42, 1.54); 8-21 days: 0.77 (95 %CI: 0.53, 1.16); 1-21 days: 0.78 (95 %CI: 0.53, 1.16)) rotavirus vaccine dose. Our findings are consistent with other data showing no increased intussusception risk with rotavirus vaccination in low-income countries and add to the growing body of evidence demonstrating safety of rotavirus vaccines.


Subject(s)
Intussusception , Rotavirus Infections , Rotavirus Vaccines , Rotavirus , Humans , Infant , Intussusception/chemically induced , Intussusception/epidemiology , Pakistan/epidemiology , Rotavirus Infections/epidemiology , Rotavirus Infections/prevention & control , Rotavirus Infections/complications , Rotavirus Vaccines/adverse effects , South Africa , Vaccination/adverse effects
3.
Sci Rep ; 13(1): 10947, 2023 Jul 06.
Article in English | MEDLINE | ID: mdl-37414797

ABSTRACT

The flow at a time-independent separable stagnation point on a Riga plate under thermal radiation and electro-magnetohydrodynamic settings is examined in this research. Two distinct base fluids-H2O and C2H6O2 and TiO2 nanostructures develop the nanocomposites. The flow problem incorporates the equations of motion and energy along with a unique model for viscosity and thermal conductivity. Similarity components are then used to reduce these model problem calculations. The Runge Kutta (RK-4) function yields the simulation result, which is displayed in graphical and tabular form. For both involved base fluid theories, the nanofluids flow and thermal profiles relating to the relevant aspects are computed and analyzed. According to the findings of this research, the C2H6O2 model heat exchange rate is significantly higher than the H2O model. As the volume percentage of nanoparticles rises, the velocity field degrades while the temperature distribution improves. Moreover, for greater acceleration parameters, TiO2/ C2H6O2has the highest thermal coefficient whereas TiO2/ H2O has the highest skin friction coefficient. The key observation is that C2H6O2 base nanofluid has a little higher performance than H2O nanofluid.


Subject(s)
Acceleration , Nanocomposites , Bone Plates , Computer Simulation
4.
Sci Rep ; 13(1): 7009, 2023 Apr 28.
Article in English | MEDLINE | ID: mdl-37117488

ABSTRACT

This study looks at the natural convections of Cu + Al2O3/H2O nanofluid into a permeable chamber. The magnetic field is also executed on the flow field and the analysis has been approached numerically by the control volume method. The study of hybrid nanofluid heat in terms of the transfer flux was supplemented with a wide range of parameters of hybrid nanofluid fractions, Rayleigh numbers Hartmann numbers and porosity factor. It's also determined that the flow and thermal distribution are heavily affected by the concentration of the nanoparticles. The concentration of nanoparticles increases the transport of convective energy inside the enclosure. The primary findings demonstrate that a rise in both the Rayleigh number and Darcy number leads to an improvement in convective heat transfer within the enclosure. However, the porosity has a negligible effect. Additionally, the rotation in a clockwise direction has a beneficial impact on the dispersion of heat transfer throughout the cavity. Furthermore, it is concluded that hybrid nanofluids are more reliable than conventional fluids in improving thermal properties.

5.
Heliyon ; 9(4): e15089, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37089381

ABSTRACT

The current investigation employs a numerical simulation to demonstrate the impact of hall current on unsteady free convective flow caused by hybrid-nanofluid over a revolving sphere approaching the stagnation point. The prominent characteristics of Lorentz force as a result of magnetic field coupling with hybrid nanofluid is also explored. The process of energy and mass transmission is inspected with nonlinear thermal radiations, non-uniform energy supply, dissipation and nonlinear chemical reaction. In current flow model, a unique class of nanofluid known as the hybrid nanofluid is being used, which contain GO (graphene oxide) and MoS 2 (molybdenum disulfide) with water. The angular speed of both the sphere and free stream changes frequently with time. Employing adequate dimensionless variables, the partial-differential patterns strongly non-linear that represent the situational analysis are morphed into non-linear ordinary differential patterns. The analytical outcomes of ordinary differential pattern have been developed via OHAM technique. Utilizing tables and graphs, various aspects of such controllable physical characteristics have been highlighted and explored in depth. For varying values of M , φ , δ , S c and K n ,the variations in C f x , C f z , N u and S h in MoS 2 -GO/H 2 O are the greatest as contrasted to MoS 2 /H 2 O. The results are also compared to those reported existing literature and they are noticed to be in very close agreement.

6.
Sci Rep ; 13(1): 2006, 2023 Feb 03.
Article in English | MEDLINE | ID: mdl-36737636

ABSTRACT

Hybrid nanofluids are extremely important in field of engineering and technology due to their higher heat transportation performance resulting in increased heat transfer rates. In the presence of thermal heat flux, the effect of a slanted MHD with velocity slip condition on a CNTs hybrid nanocomposite across a gradually extending surface is investigated. In present analysis, Maxwell nanofluid is embedded with SWCNT and MWCNT (single and multiple wall carbon nanotubes) nanoparticles. The nanomaterials transformation framework is obtained by employing Xue modified theoretical model. Various factors like dissipation, thermal radiations and Ohmic heat influences are adequately implemented in heat formulation. The physical features of thermodynamical mechanism of irreversibility are explored. The thermodynamics second law is used to produce the entropy optimization formulation. In addition, entropy is utilized to assess the energy aspects of a heat exchanger. Utilizing appropriate parameters, the model nonlinear PDEs are transformed to ODEs. The HAM technique is used to compute the solution of nonlinear ODEs. For both types of CNTs, the variations of entropy rate, Bejan number, velocity and temperature field versus key technical parameters is analyzed. The Nu and Cf computational result for both CNTs are examined in tabulated and chart form. Velocity is inversely proportional to magnetic and solid volume nanoparticle parameters. The Br and Rd accelerates NG and Be for both nanocomposites. Additionally, a comparison of the HAM result and the numerical result is validated.

7.
Sci Rep ; 11(1): 18410, 2021 Sep 15.
Article in English | MEDLINE | ID: mdl-34526582

ABSTRACT

To enhance the surface properties of solids the mechanism of thin films is frequently used. Penetration, degradation, stiffness, illumination, diffusion, absorption, and electric performance are all characteristics of a bulk substance medium that a thin film can improve. In nanotechnology, thin film processing can be extremely useful. Therefore, the time-dependent nonlinearly convective stream of thin film nanoliquid over an inclined stretchable sheet with magnetic effect is investigated in current work. The features of mass and heat transport processes are explained using important factors like thermophoresis and Brownian movement. Nonlinear partial differential equations are obtained to model the time-dependent liquid film flow over an inclined surface, which are then turned into couple ordinary differential equations utilizing appropriate alterations. The results of the computation of the model problem are collected using an analytical approach Homotopy Analysis Method and presented the final finding numerically and graphically. During the flow assessment, the impact of individual flow factors such as magnetic, Brownian, and thermophoresis parameters on regular profiles (temperature, velocity, and concentration) are analyzed and found to be quite remarkable. Furthermore, the consequence of M and Nt factors on the velocity, concentration and thermal distribution leads to diminishing conduct. On the other hand, the thermal profile of the liquid film rises in response to the thermophoresis factor. The % wise variation in the skin friction, Nusselt number and Sherwood number versus physical parameters has been obtained and discussed.

8.
J Coll Physicians Surg Pak ; 31(1): S75-S78, 2021 01.
Article in English | MEDLINE | ID: mdl-34530534

ABSTRACT

OBJECTIVE: To document the measures adopted during the COVID-19 pandemic strict lockdown on pediatric surgical services and residents' training at a tertiary care hospital. STUDY DESIGN: Cross-sectional descriptive study. PLACE AND DURATION OF STUDY: Department of Pediatric Surgery, National Institute of Child Health, Jinnah Sindh Medical University, Karachi, from April 2020 to June 2020. METHODOLOGY: Data from the Outpatient Department, Emergency Department, and Operation Theatre records were collected. The number of patients seen in the outpatient department, surgeries performed, index emergency cases dealt with, and the residents' duty roster and teaching methodology were documented. Descriptive statistics were used for reporting. RESULTS: During the strict lockdown period, outpatient services continued; however, elective cases were not operated. A total of 2,930 patients were seen in clinics, and 1,316 surgical procedures were performed. The index cases managed included anorectal malformation (n=35), esophageal atresia with and without tracheoesophageal fistula (n=13), small bowel atresia (n=11), omphalocele (n=6), acute appendicitis (n=35), intestinal obstructions (n=23), intussusceptions (n=18), and intestinal perforations (n=16). On-call days of residents were reduced from every third to the fifth day, and online educational sessions were added. During the pandemic, 13 members of surgical and anaesthesia teams got infected with COVID-19. CONCLUSION: COVID-19 pandemic elective surgical services were restricted; however, emergency cases were managed as per routine. In clinical teaching, virtual technologies were incorporated. Working hours of residents were limited to decrease the exposure to infected persons. Key Words: COVID-19, SARS-CoV-2 pandemic, Healthcare workers, Residency programme.


Subject(s)
COVID-19 , Internship and Residency , Child , Communicable Disease Control , Cross-Sectional Studies , Humans , Pandemics , SARS-CoV-2
9.
Sci Rep ; 11(1): 16708, 2021 08 18.
Article in English | MEDLINE | ID: mdl-34408217

ABSTRACT

This work investigates numerically the solution of Darcy-Forchheimer flow for hybrid nanofluid by employing the slip conditions. Basically, the fluid flow is produced by a swirling disk and is exposed to thermal stratification along with non-linear thermal radiation for controlling the heat transfer of the flow system. In this investigation, the nanoparticles of titanium dioxide and aluminum oxide have been suspended in water as base fluid. Moreover, the Darcy-Forchheimer expression is used to characterize the porous spaces with variable porosity and permeability. The resulting expressions of motion, energy and mass transfer in dimensionless form have been solved by HAM (Homotopy analysis method). In addition, the influence of different emerging factors upon flow system has been disputed both theoretically in graphical form and numerically in the tabular form. During this effort, it has been recognized that velocities profiles augment with growing values of mixed convection parameter while thermal characteristics enhance with augmenting values of radiation parameters. According to the findings, heat is transmitted more quickly in hybrid nanofluid than in traditional nanofluid. Furthermore, it is estimated that the velocities of fluid [Formula: see text] are decayed for high values of [Formula: see text] and [Formula: see text] factors.

10.
Sci Rep ; 11(1): 12865, 2021 06 18.
Article in English | MEDLINE | ID: mdl-34145347

ABSTRACT

In this investigation, heat transportation together with irreversibility analysis for the flow of couple stress hybrid nanofluid past over a stretching surface is considered. The innovative characteristics and aims of this work are to note that the transportation heat couple stress model involves EMHD, viscous dissipation, Joule heating, and heat absorption, and omission. The hybrid nanofluid is prepared due to the suspension of the solid nanoparticles of the SWCNTs and MWCNTs in pure human blood. This mathematical model is an appropriate model for biological advantages including testing of human blood for drug deliveries to various parts of the human body. Particularly, the Prandtl number used for the blood is 21 and very large as compared to the other base fluids. Necessary modifications are used to translate the defining partial differential equations and boundary conditions into a layout that can be computed. To obtain mathematical approximations for the resulting scheme of nonlinear differential equations, the innovative homotopy analysis method (HAM) is used. The explanation for velocity, energy, and entropy are exposed and the flow against various influential factors ([Formula: see text]) is discussed graphically. The numerical values are calculated and summarized for dimensionless [Formula: see text] In addition, the current study is compared for various values of [Formula: see text] to that published literature and an impressive agreement in terms of finding is reported. It has also been noticed that the [Formula: see text] and [Formula: see text] factors retard the hybrid nanofluid flow, while the temperature of fluid becomes upsurges by the rise in these factors. 11.95% enhancement in the heat transfer rate has been attained using the hybrid nanofluids.


Subject(s)
Electromagnetic Fields , Hydrodynamics , Models, Theoretical , Stress, Mechanical , Algorithms , Humans , Solutions , Temperature
11.
PLoS One ; 16(5): e0249434, 2021.
Article in English | MEDLINE | ID: mdl-33961625

ABSTRACT

The present article provides a detailed analysis of the Darcy Forchheimer flow of hybrid nanoliquid past an exponentially extending curved surface. In the porous space, the viscous fluid is expressed by Darcy-Forchheimer. The cylindrical shaped carbon nanotubes (SWCNTs and MWCNTs) and Fe3O4 (iron oxide) are used to synthesize hybrid nanofluid. At first, the appropriate similarity transformation is used to convert the modeled nonlinear coupled partial differential equations into nonlinear coupled ordinary differential equations. Then the resulting highly nonlinear coupled ordinary differential equations are analytically solved by the utilization of the "Homotopy analysis method" (HAM) method. The influence of sundry flow factors on velocity, temperature, and concentration profile are sketched and briefly discussed. The enhancement in both volume fraction parameter and curvature parameter k results in raises of the velocity profile. The uses of both Fe3O4 and CNTs nanoparticles are expressively improving the thermophysical properties of the base fluid. Apart from this, the numerical values of some physical quantities such as skin friction coefficients, local Nusselt number, and Sherwood number for the variation of the values of pertinent parameters are displayed in tabular forms. The obtained results show that the hybrid nanofluid enhances the heat transfer rate 2.21%, 2.1%, and 2.3% using the MWCNTs, SWCNTs, and Fe3O4 nanomaterials.


Subject(s)
Hot Temperature , Convection , Nanotubes, Carbon , Nonlinear Dynamics , Porosity , Surface Properties
12.
Sci Rep ; 11(1): 7460, 2021 04 02.
Article in English | MEDLINE | ID: mdl-33811244

ABSTRACT

In this new world of fluid technologies, hybrid nanofluid has become a productive subject of research among scientists for its potential thermal features and abilities, which provides an excellent result as compared to nanofluids in growing the rate of heat transport. Our purpose here is to introduce the substantial influences of magnetic field on 2D, time-dependent and stagnation point inviscid flow of couple stress hybrid nanofluid around a rotating sphere with base fluid is pure blood, [Formula: see text] as the nanoparticles. To translate the governing system of partial differential equations and the boundary conditions relevant for computation, some suitable transformations are implemented. To obtain the analytical estimations for the corresponding system of differential expression, the innovative Optimal Homotopy Analysis Method is used. The characteristics of hybrid nanofluid flow patterns, including temperature, velocity and concentration profiles are simulated and analyzed in detail due to the variation in the evolving variables. Detailed research is also performed to investigate the influences of relevant constraints on the rates, momentum and heat transport for both [Formula: see text] and [Formula: see text]. One of the many outcomes of this analysis, it is observed that increasing the magnetic factor will decelerate the hybrid nanofluid flow velocity and improve the temperature profile. It may also be demonstrated that by increasing the Brownian motion factor, significant improvement can be made in the concentration field of hybrid nanofluid. The increase in the nanoparticle volume fraction from 0.01 to 0.02 in the case of the hybrid nanofluid enhances the thermal conductivity from 5.8 to 11.947% and for the same value of the nanoparticle volume fraction in the case of nanofluid enhance the thermal conductivity from 2.576 to 5.197%.

13.
Clinical Endoscopy ; : 250-255, 2021.
Article in English | WPRIM (Western Pacific) | ID: wpr-890052

ABSTRACT

Background/Aims@#The adenoma detection rate (ADR) is used as a quality indicator for screening and surveillance colonoscopy. The study aimed to determine if moderate versus deep sedation affects the outcomes of the ADR and other quality metrics in the veteran population. @*Methods@#A retrospective review of colonoscopies performed at Memphis Veterans Affairs Medical Center over a one-year period was conducted. A total of 900 colonoscopy reports were reviewed. After exclusion criteria, a total of 229 index, average-risk screening colonoscopies were identified. Data were collected to determine the impact of moderate (benzodiazepine plus opioids) versus deep (propofol) sedation on the ADR, polyp detection rate (PDR), and withdrawal time. @*Results@#Among 229 screening colonoscopies, 103 (44.9%) used moderate sedation while 126 (55%) were done under deep sedation. The ADR and PDR were not significantly different between moderate versus deep sedation at 35.9% vs. 37.3% (p=0.82) and 58.2% vs. 48.4% (p=0.13), respectively. Similarly, there was no significant difference in withdrawal time between moderate and deep sedation (13.4 min vs. 14 min, p=0.56) during screening colonoscopies. @*Conclusions@#In veterans undergoing index, average-risk screening colonoscopies, the quality metrics of the ADR, PDR, and withdrawal time are not influenced by deep sedation compared with moderate sedation.

14.
Clinical Endoscopy ; : 250-255, 2021.
Article in English | WPRIM (Western Pacific) | ID: wpr-897756

ABSTRACT

Background/Aims@#The adenoma detection rate (ADR) is used as a quality indicator for screening and surveillance colonoscopy. The study aimed to determine if moderate versus deep sedation affects the outcomes of the ADR and other quality metrics in the veteran population. @*Methods@#A retrospective review of colonoscopies performed at Memphis Veterans Affairs Medical Center over a one-year period was conducted. A total of 900 colonoscopy reports were reviewed. After exclusion criteria, a total of 229 index, average-risk screening colonoscopies were identified. Data were collected to determine the impact of moderate (benzodiazepine plus opioids) versus deep (propofol) sedation on the ADR, polyp detection rate (PDR), and withdrawal time. @*Results@#Among 229 screening colonoscopies, 103 (44.9%) used moderate sedation while 126 (55%) were done under deep sedation. The ADR and PDR were not significantly different between moderate versus deep sedation at 35.9% vs. 37.3% (p=0.82) and 58.2% vs. 48.4% (p=0.13), respectively. Similarly, there was no significant difference in withdrawal time between moderate and deep sedation (13.4 min vs. 14 min, p=0.56) during screening colonoscopies. @*Conclusions@#In veterans undergoing index, average-risk screening colonoscopies, the quality metrics of the ADR, PDR, and withdrawal time are not influenced by deep sedation compared with moderate sedation.

15.
J Infect Dis ; 221(9): 1499-1505, 2020 04 07.
Article in English | MEDLINE | ID: mdl-31754717

ABSTRACT

BACKGROUND: The etiology of intussusception, the leading cause of bowel obstruction in infants, is unknown in most cases. Adenovirus has been associated with intussusception and slightly increased risk of intussusception with rotavirus vaccination has been found. We conducted a case-control study among children <2 years old in Bangladesh, Nepal, Pakistan, and Vietnam to evaluate infectious etiologies of intussusception before rotavirus vaccine introduction. METHODS: From 2015 to 2017, we enrolled 1-to-1 matched intussusception cases and hospital controls; 249 pairs were included. Stool specimens were tested for 37 infectious agents using TaqMan Array technology. We used conditional logistic regression to estimate odds ratio (OR) and 95% confidence interval (CI) of each pathogen associated with intussusception in a pooled analysis and quantitative subanalyses. RESULTS: Adenovirus (OR, 2.67; 95% CI, 1.75-4.36) and human herpes virus 6 (OR, 3.50; 95% CI, 1.15-10.63) were detected more frequently in cases than controls. Adenovirus C detection <20 quantification cycles was associated with intussusception (OR, 18.59; 95% CI, 2.45-140.89). Wild-type rotavirus was not associated with intussusception (OR, 1.07; 95% CI, 0.52-2.22). CONCLUSIONS: In this comprehensive evaluation, adenovirus and HHV-6 were associated with intussusception. Future research is needed to better understand mechanisms leading to intussusception, particularly after rotavirus vaccination.


Subject(s)
Adenoviruses, Human/isolation & purification , Feces/virology , Herpesvirus 6, Human/isolation & purification , Intussusception/epidemiology , Intussusception/virology , Asia , Case-Control Studies , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Logistic Models , Male , Rotavirus/isolation & purification , Rotavirus Vaccines
16.
Entropy (Basel) ; 21(8)2019 Aug 16.
Article in English | MEDLINE | ID: mdl-33267514

ABSTRACT

In this research work, a 3D rotating flow of carbon nanotubes (CNTs) over a porous stretchable sheet for heat and mass transfer is investigated. Kerosene oil is considered as a base liquid and two types of CNTs, (Single & Multi) WCNTs are added as the additives to the base liquid. The present analysis further comprises the combined effect of the Hall, ion-slip, and thermal radiation, along with heat generation/absorption. The appropriate ordinary differential system of equations after applying appropriate transformation is calculated. The resulting nonlinear system of equations (conservation of mass, momentum, temperature) is explained by HAM (Homotopy Analysis Method). Solution of velocities and thermal fields are obtained and discussed graphically. Expression of C f and N u are intended for both type of nanoliquids. The influences of prominent physical factors are plotted for velocities and thermal profiles using Methematica. These graphical results are qualitatively in excellent agreement with the previous published results. Also, single wall nanoparticles are found to have higher temperatures than multi wall CNTs nanoparticles.

18.
J Coll Physicians Surg Pak ; 20(5): 337-8, 2010 May.
Article in English | MEDLINE | ID: mdl-20642929

ABSTRACT

Anterior sacral meningocele is a rare condition presenting as a lower abdominal mass. One such case was seen in a baby girl aged 2 months, who was admitted with abdominal distension and urinary difficulty for one week. She had a lower abdominal mass which investigated by MRI, turned out to be an anterior sacral meningocele causing her symptoms. The meningocele was excised successfully via an open abdominal approach. Postoperative recovery and follow-ups remained uneventful. Presentation, various diagnostic modalities and treatment options for an anterior sacral meningocele are briefly discussed.


Subject(s)
Meningocele/diagnosis , Sacrum , Female , Humans , Infant , Meningocele/complications , Meningocele/therapy
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