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Introduction: Aminoglycosides used for treating multidrug-resistant (MDR) tuberculosis are ototoxic, leading to a need for audiological monitoring. While audiologists monitor ototoxicity, currently there are no guidelines on monitoring in the South African context. Therefore, the findings of this study might help to motivate the establishment of a more in-depth ototoxicity monitoring policy, which facilitates uniformity among audiologists managing patients with MDR tuberculosis. Therefore, the study aimed to describe the audiological practices employed by audiologists in the management of adult patients with MDR tuberculosis in South Africa.Method: A descriptive survey design was used. A questionnaire was developed and included elements of the American Speech-Language and Hearing Association (1994) guidelines for monitoring ototoxicity. Ninety-three audiologists contributed data to this study. Descriptive statistics were used in the analysis of the data.Results: Sixty-eight percent (%) of the respondents were aware of the international guidelines, 93% provided pre-treatment counselling and 87% conducted a baseline assessment. Nineteen percent of the respondents conducted high-frequency audiometry, while 74% carried out a monthly evaluation, 72% performed a full audiological assessment after the cessation of the MDR tuberculosis treatment, and 96% conducted post-treatment counselling. Modifications to the international guidelines include not conducting speech and immittance audiometry, as well as testing certain frequencies. The reasons for these modifications include limited specialised equipment, time constraints, large caseloads and understaffed departments.Conclusion: There are no explicit guidelines on ototoxicity monitoring in South Africa. Consequently, audiologists are having to modify the international guidelines. Thus, there is no consistency in managing patients with MDR tuberculosis. This highlights the need for South Africa to develop context-relevant ototoxicity monitoring guidelines to appropriately manage patients with MDR tuberculosis.

In this paper, we discuss the Bianchi type-I cosmological model in the framework of symmetric teleparallel gravity say f(Q)gravity in which the non-metricity term Qis responsible for the gravitational interaction. We consider a special form of the f(Q)function which can be cast as f(Q)=λQn, where λand nboth are the dynamical model parameters. Such a choice can be viewed as a hybrid scale factor that leads to a relation between cosmic time and redshift as t=(αt0β)W[βαeβ−ln⁡(1+z)α]which describes a ΛCDM model of the Universe with the expansion evolving from decelerating to an acceleration phase. The best values for the model parameters i.e. αand βthat would accord with the most current observational datasets are then estimated. We make use of 57 points from the Hubble dataset, 1048 points from the supernovae of type Ia dataset and 6 points from the BAO dataset. We use the Markov Chain Monte Carlo (MCMC) technique in conjunction with Bayesian analysis and the likelihood function. Further, we study the validity of our model with the investigation of the thermodynamical quantities, energy conditions along with some physical variables such as the EoS, and jerk parameters. Next, our results are discussed in light of current observational data and trends.

In this paper we present a simple generalisation of all spherically symmetric static solutions. We present a framework to obtain both anisotropic and isotropic models with and without a barotropic equation of state of the form p= α ρ. The nonstaticity in some models necessarily requires a nonzero heat flux which dictates the thermodynamics of our models.

We investigate the evolution of the temperature profile of a Friedmann-like collapsing sphere undergoing dissipative gravitational collapse in the form of a radial heat flux. We further consider the behavior of the star close to quasi-static equilibrium (weak heat flux approximation) and show that relaxational effects cannot be ignored. It is explicitly shown that extended irreversible thermodynamics predict a higher temperature at all interior points of the stellar configuration compared to the Eckart theory. These results carry over to the weak heat flux approximation with the magnitude of the temperature being lower than the full radiating model. The stability of the model after its departure from equilibrium is studied by considering the behavior of the “control parameter” throughout the stellar interior.

We investigate the effect of heat dissipation in inhomogeneous cosmologies by invoking the full causal theory of heat transport within the framework of extended irreversible thermodynamics. This work extends earlier results which were obtained using the truncated causal heat transport equation. In particular, we show that the truncation of the heat transport equation implicitly defines a temperature law which leads to pathological behaviour in the temperature of the evolving cosmic fluid.

The junction conditions for a magnetohydrodynamic fluid sphere undergoing dissipative gravitational collapse in the form of a radial heat flux with shear are obtained. These conditions extend particular results of earlier treatments. We demonstrate that the pressure is proportional to the magnitude of the heat flux as is the case in shear-free models. However in our case the gravitational potentials must be solutions of the Einstein-Maxwell system of equations. The mass function m(v) is increased by a factor related to the charge Qof the radiating star. Physical quantities relating to the local conservation of momentum and surface redshift are obtained.

We find a simple inflationary solution in aninhomogeneous spacetime with heat flux. The heat fluxobeys a causal transport equation, and counteracts theinflationary decrease of energy density. At late times, the heat flux tends to zero and thefluid approaches the equation of state p =–ρ.

We study the behaviour of the model for a radiating star proposed by Kramer. The evolution of the model is governed by a second order nonlinear differential equation. The general solution of this equation is expressed in terms of elementary and special functions. This completes the solution of the Einstein field equations for the interior of the star. The model matches smoothly to the Vaidya exterior solution and the condition p = qB is satisfied at the boundary. We briefly study the thermodynamics of the model and indicate the difficulty in specifying the temperature explicitly.