Present study deals with the buoyancy assisted or opposed Falkner-Skan nanofluid flow over a heated wedge. Firstly, the problem is formulated via single phase model by assuming that nanoparticle ...working fluid is water based and comprises of different nanoparticle materials namely copper (Cu), copper oxide (CuO), Alumina (Al2O3) and Titania (TiO2). Partial slip assumption is employed which results in the Robin–type condition in longitudinal velocity component. The resulting heat transfer process with a prescribed surface temperature is also formulated and analyzed using thermal slip condition. The governing problem is transformed into a coupled self-similar boundary value problem whose numerical solution is developed by MATLAB package bvp4c based on the collocation approach. Computational results for velocity field and temperature are scrutinized for full ranges of solid volume fraction (ϕ) and pressure gradient parameter (m) under both assisting and opposing flow scenarios. The computational results clearly demonstrate that nanofluid assumption is indeed vital for thermal conductivity enhancement of convectional heat transfer fluids. The problem is also investigated by using Buongiorno model in a special case (m = 0), when fluid properties and wall temperature are kept constant. Numerical solutions indicate that there is no noticeable change in temperature profile by changing Brownian diffusion and thermophoresis parameters.
β-Lactamases can accumulate stepwise mutations that increase their resistance profiles to the latest β-lactam agents. CMY-185 is a CMY-2-like β-lactamase and was identified in an
clinical strain ...isolated from a patient who underwent treatment with ceftazidime-avibactam. CMY-185, possessing four amino acid substitutions of A114E, Q120K, V211S, and N346Y relative to CMY-2, confers high-level ceftazidime-avibactam resistance, and accumulation of the substitutions incrementally enhances the level of resistance to this agent. However, the functional role of each substitution and their interplay in enabling ceftazidime-avibactam resistance remains unknown. Through biochemical and structural analysis, we present the molecular basis for the enhanced ceftazidime hydrolysis and impaired avibactam inhibition conferred by CMY-185. The substituted Y346 residue is a major driver of the functional evolution as it rejects primary avibactam binding due to the steric hindrance and augments oxyimino-cephalosporin hydrolysis through a drastic structural change, rotating the side chain of Y346 and then disrupting the H-10 helix structure. The other substituted residues E114 and K120 incrementally contribute to rejection of avibactam inhibition, while S211 stimulates the turnover rate of the oxyimino-cephalosporin hydrolysis. These findings indicate that the N346Y substitution is capable of simultaneously expanding the spectrum of activity against some of the latest β-lactam agents with altered bulky side chains and rejecting the binding of β-lactamase inhibitors. However, substitution of additional residues may be required for CMY enzymes to achieve enhanced affinity or turnover rate of the β-lactam agents leading to clinically relevant levels of resistance.IMPORTANCECeftazidime-avibactam has a broad spectrum of activity against multidrug-resistant Gram-negative bacteria including carbapenem-resistant
including strains with or without production of serine carbapenemases. After its launch, emergence of ceftazidime-avibactam-resistant strains that produce mutated β-lactamases capable of efficiently hydrolyzing ceftazidime or impairing avibactam inhibition are increasingly reported. Furthermore, cross-resistance towards cefiderocol, the latest cephalosporin in clinical use, has been observed in some instances. Here, we clearly demonstrate the functional role of the substituted residues in CMY-185, a four amino-acid variant of CMY-2 identified in a patient treated with ceftazidime-avibactam, for high-level resistance to this agent and low-level resistance to cefiderocol. These findings provide structural insights into how β-lactamases may incrementally alter their structures to escape multiple advanced β-lactam agents.
This manuscript explores the plasmonic characteristics of monolayer graphene in anisotropic plasma dielectric planar structure. The complex conductivity of monolayer graphene is modeled by Kubo ...formulism. Due to anisotropy of plasma medium, higher and lower modes are demonstrated to explore the properties of proposed waveguide structure. Incident frequency-dependent both propagating modes are discussed for normalized phase constant as well as phase velocity under the different values of chemical potential, relaxation time, number of graphene layers, electron plasma frequency and cyclotron frequency. Field profiles for anisotropic dielectric are also presented to confirm electromagnetic surface waves condition. The presented results are being used to increase the efficiency of a graphene-based chip photonic system.
In current numerical investigation, irreversibility and energy transportation related to free convection though a porous wavy chamber was scrutinized. One of the essential factors in design of unit ...is irreversibility which should be minimized. The inner wavy surface acts as heat element and chamber is filled with hybrid nanomaterial. New correlations, contours and profiles are main kinds of outputs which achieved by employing CVFEM. As Ra augments, the magnitude of ψmax enhances which indicates higher convective mode, and better cooling rate of inner wall happens. At lowest Ra and Nhs, Nu declines about 57.2% and Be augments about 2.75% with augmenting Lorentz force. Nu becomes 7.5 times greater with growth of Ra when other variables are minimum. Be reduces about 2.49% with rise of Nhs at Ra⁎ = 5, Ha = 20. Portion of thermal irreversibility augments with impose of stronger magnetic field. Growth of Ra leads to domination of convective mode and hence inner wall become colder. Reduction impact of Nhs on Nu become more stronger when buoyancy force augments. In comparison with Ra, Nhs has no sensible impact on Be.
Abstract
Background
With increasing global availability of medication abortion drugs, a safer option exists for many women to terminate a pregnancy even in legally restrictive settings. However, more ...than 22,000 women die each year from unsafe abortion, most often in developing countries where abortion is highly legally restricted. We conducted a systematic review to compile existing evidence regarding factors that influence women’s abortion-related decision making in countries where abortion is highly legally restricted.
Methods
We searched ten databases in two languages (English and Spanish) for relevant literature published between 2000 and 2019 that address women’s decision-making regarding when, where and how to terminate a pregnancy in sub-Saharan African, Latin American and the Caribbean countries where abortion is highly legally restricted.
Results
We identified 46 articles that met the review’s inclusion criteria. We found four primary factors that influenced women’s abortion-related decision-making processes: (1) the role of knowledge, including of laws, methods and sources; (2) the role of safety, including medical, legal and social safety; (3) the role of social networks and the internet, and; (4) cost affordability and convenience.
Conclusions
The choices women make after deciding to terminate a pregnancy are shaped by myriad factors, particularly in contexts where abortion is highly legally restricted. Our review catalogued the predominant influences on these decisions of when, where and how to abort. More research is needed to better understand how these factors work in concert to best meet women’s abortion needs to the full limit of the law and within a harm reduction framework for abortions outside of legal indications.
Applications of a quadrotor with payload, particularly for chemical spraying, have increased in recent times. The variation in payload mass over time causes a change in the moments of inertia (MOI). ...Moreover, large tilt angles are required for fast reference tracking and external disturbance rejection. These variations in plant parameters (i.e., mass and inertia) and large tilt angles can degrade the control scheme’s performance and stability. This article proposes a linear matrix inequalities (LMIs)-based linear parameter varying (LPV) control scheme for a quadrotor subject to time-varying mass, time-varying inertia, mass flow rate, and large tilt angles. The control strategy is designed by solving LMIs derived from quadratic H∞ performance and D-stability. The robust stability and quadratic H∞ performance are assessed by LMIs. The efficacy of the proposed methodology is established using numerical simulations, and its performance is compared to the linear time-invariant (LTI) H∞ design with pole placement constraints. The results obtained show that the LPV control scheme gives better tracking performance in the presence of time-varying parameters, noise, and external disturbances without actuator saturation. In comparison to the LTI design technique, the proposed LPV scheme improves the rise time (tr), settling time (ts), and mean squared error (MSE) by up to 14%, 15%, and 30%, respectively. Moreover, smooth transitions are observed in the tilt angles and control signals with the LPV scheme, contrary to the LTI controller, which exhibits significant oscillations.
Nanofluid dynamics with magnetohydrodynamics has tremendously contributed in industrial applications recently since presence of nanoparticle in base fluids enhances the specific chemical and physical ...properties. Owing to the relevance of nanofluid dynamics, we analyze the nanofluid flow in the presence of gyrotactic microorganism and magnetohydrodynamics through a stretching/shrinking plate. The impacts of chemical reaction and thermal radiation on flow characteristics are also studied. To simplify the governing equations of microorganisms, velocity, concentration and temperature, the similarity transformations are employed. The couple governing equations are numerically solved using Successive Taylor Series Linearization Method (STSLM). The velocity profile, motile microorganism density profile, concentration profile, temperature profile as well as Nusselt number, skin friction coefficient, Sherwood number and density number of motile microorganisms are discussed using tables and graphs against all the sundry parameters. A numerical comparison is also given for Nusselt number, Sherwood number, skin friction, and density number of motile microorganisms with previously published results to validate the present model. The results show that Nusselt number, Sherwood number and density number diminish with increasing the magnetic field effects.
Background
Although repetitive transcranial magnetic stimulation (rTMS) has been assessed in epileptic humans, clinical trials in epileptic dogs can provide additional insight.
Objectives
Evaluate ...the potential antiepileptic effect of rTMS in dogs.
Animals
Twelve client‐owned dogs with drug‐resistant idiopathic epilepsy (IE).
Methods
Single‐blinded randomized sham‐controlled clinical trial (dogs allocated to active or sham rTMS) (I) and open‐labeled uncontrolled clinical trial (dogs received active rTMS after sham rTMS) (II). Monthly seizure frequency (MSF), monthly seizure day frequency (MSDF), and number of cluster seizures (CS) were evaluated for a 3‐month pre‐TMS and post‐rTMS period and safety was assessed. The lasting effect period of rTMS was assessed in each dog treated by active stimulation using the MSF ratio (proportion of post‐TMS to pre‐rTMS MSF) and treatment was considered effective if the ratio was <1.
Results
No adverse effects were reported. In trial I, MSF and MSDF decreased significantly (P = .04) in the active group (n = 7). In the sham group (n = 5), no significant changes were found (P = .84 and .29, respectively). Cluster seizures did not change significantly in either group. No significant differences were detected between the groups. In trial II, previously sham‐treated dogs (n = 5) received active rTMS and significant decreases in MSF and MSDF were noted (P = .03 and .008, respectively). The overall effect of rTMS lasted for 4 months; thereafter, the MSF ratio was >1.
Conclusions and Clinical Importance
Repetitive transcranial magnetic stimulation may be a safe adjunctive treatment option for dogs with drug‐resistant IE, but large‐scale studies are needed to establish firm conclusions.
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