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The article focuses on the analyses presented in the "MMWR Supplement" "National HIV Behavioral Surveillance Among Transgender Women--Seven Urban Areas, 2019-2020" which highlights findings from the U.S. Centers for Disease Control and Prevention's National HIV Behavioral Surveillance Among Transgender Women (NHBS-Trans) project from 2019-2020. Topics include social marginalization and discrimination experienced by transgender women and considerations that are relevant to one's HIV risk.

Gliomatosis peritonei is a rare complication of ovarian teratomas characterized by peritoneal implants of glial tissue. Glial tissue in such cases is usually low grade although there have been cases of malignant evolution described. There is no clear guidance as to how often and for how long these patients should be followed up. There are clear dose implications when performing multiple CT scans. We present a case of immature ovarian teratoma complicated by the development of low grade gliomatosis peritonei. The MRI appearances are presented and described, and we discuss the potential role of MRI in the follow up of such cases. [ABSTRACT FROM AUTHOR]

Analytical solutions for the initial rise height $z_m$ of a turbulent fountain for the limits of both small and large source Froude number $\hbox{\it Fr}_0$ are presented. These solutions are based on a plume entrainment model. For large Froude number fountains, the established result $z_m/r_0{\,\sim\,}\hbox{\it Fr}_0$ is obtained ($r_0$ denoting the source radius). For intermediate Froude numbers, the relationship $z_m/r_0{\,\sim\,}\hbox{\it Fr}_0^2$ is found and the rise height is independent of the entrainment coefficient $\alpha$. For very small Froude numbers, the flow is hydraulically controlled at the source and $z_m/r_0{\,\sim\,}\hbox{\it Fr}_0^{2/3}$. Existing experimental and numerical results, as well as our own experimental results, are compared to our solutions and show good agreement. Comparison with experimental results also demonstrates that the appropriate entrainment coefficient for highly forced fountains is $\alpha_f{\,\approx\,}0.058$. This is significantly closer to the entrainment coefficient of a jet than of a plume. [ABSTRACT FROM AUTHOR]

The collision of axisymmetric turbulent plumes with buoyancy fluxes of opposite sign is examined experimentally. The total buoyancy flux loss of each plume as a result of the collision is measured. The measurements are made using a new experimental technique for measuring the buoyancy flux of a plume based on the ventilation theory of Linden, Lane-Serff & Smeed (J. Fluid Mech. vol. 212, 1990, p. 309). The experimental results are presented as functions of the buoyancy flux ratio $\psi$ and the ratio of radial to vertical separation $\sigma $. For axially aligned plumes we find that the lower-buoyancy-flux plume loses all its buoyancy flux when $\psi \,{}\,$0.3, and that there is very little buoyancy flux loss for either plume when }\,$0.25. This plume–plume collision is modelled using a modified set of entrainment equations. The model allows for the exchange of buoyancy and deflection of the plumes as they pass by each other. We present predictions of total buoyancy flux loss as a function of both plume strength and separation. The model predictions are compared to the experimental measurements of buoyancy flux loss, and show good agreement. [ABSTRACT FROM AUTHOR]

We examine the dynamics of turbulent lazy plumes rising from horizontal area sources and from vertically distributed line sources into a quiescent environment of uniform density. First, we consider plumes with internal buoyancy flux gain and, secondly, plumes from horizontal area sources that have significant momentum flux deficits. We re-cast the conservation equations of Morton et al. (1956) for a constant entrainment coefficient $(\alpha)$ in terms of three dimensionless parameters: the plume radius $\beta$; a parameter $\Gamma$ characterizing the local balance of momentum, buoyancy and volume fluxes; and a parameter $\Lambda$ that characterizes the rate of internal buoyancy flux gain with height. For a plume with a linear internal buoyancy flux gain with height the flow is shown to be a constant-velocity lazy plume. For highly lazy area sources we derive exact solutions for the key plume parameters in terms of $\Gamma$ and an approximate solution for the variation of $\Gamma$ with height. We show that near the source there is a region of zero entrainment. [ABSTRACT FROM AUTHOR]

We examine the transient buoyancy-driven flow in a ventilated filling box that is subject to a continuous supply of buoyancy. A rectangular box is considered and the buoyancy input is represented as a turbulent plume, or as multiple non-interacting plumes, rising from the floor. Openings in the base and top of the box link the interior environment with a quiescent exterior environment of constant and uniform density. A theoretical model is developed to predict, as functions of time, the density stratification and the volume flow rate through the openings leading to the steady state. Comparisons are made with the results of small-scale analogue laboratory experiments in which saline solutions and fresh water are used to create density differences. Two characteristic timescales are identified: the filling box time ($T_f$), proportional to the time taken for fluid from a plume to fill a closed box; and the draining box time ($T_d$), proportional to the time taken for a ventilated box to drain of buoyant fluid. The timescale for the flow to reach the steady state depends on these two timescales, which are functions of the box height $H$ and cross-sectional area $S$, the ‘effective’ opening area $A^*$, and the strength, number and distribution of the buoyancy inputs. The steady-state flow is shown to be characterized by the ratio of these timescales ($\mu\,{=}\,T_d/T_f$) which is equivalent to the dimensionless vent area $A^*/H^2$. A feature of these flows is that for $\mu\,{>}\,\mu_c$ the depth of the buoyant upper layer may exceed, or ‘overshoot’, the steady layer depth during the initial transient. The value of $\mu_c$ is determined for both line and point-source plumes, and the sensitivity of the developing flow to the distribution of buoyancy input assessed. [ABSTRACT FROM AUTHOR]

The coalescence of two co-flowing axisymmetric turbulent plumes and the resulting single plume flow is modelled and compared to experiments. The point of coalescence is defined as the location at which only a single peak appears in the horizontal buoyancy profile, and a prediction is made for its height. The model takes into account the drawing together of the two plumes due to their respective entrainment fields. Experiments showed that the model tends to overestimate the coalescence height, though this discrepancy may be partly explained by the sensitivity of the prediction to the entrainment coefficient. A model is then developed to describe the resulting single plume and predict its virtual origin. This prediction and subsequent predictions of flow rate above the merge height compare very well with experimental results. [ABSTRACT FROM AUTHOR]

With the increasing geriatric population, more research is needed to identify strategies for enriching the quality of life for older adults. Music therapy has been well documented for its beneficial effects on physical and mental health. The notion of using player piano music as therapy for the elderly evolved because of the absence of this approach in the literature. Eleven elderly clients in a midwestern retirement center participated in an ABA experimental design to measure responses to player piano music. Cognitive, affective, and behavioral data were collected through observational and subjective interview tools. Results demonstrated marked increments of rhythmic and extremity responses to musical treatment. Additionally, player piano music was enjoyed and enhanced a state of well-being and youth, enabled retrieval of specific long-term memories, and provided "action-oriented" cognitive themes and stimulation. [ABSTRACT FROM AUTHOR]