Lesbian, gay, bisexual, and transgender (LGBT) health services in the United States: Origins, evolution, and contemporary landscape

Background LGBT community organizations in the United States have been providing health services since at least the 1970s. However, available explanations for the origins of LGBT health services do not sufficiently explain why health in particular has been so closely and consistently linked to LGBT activism. Little is also known regarding how LGBT health services may have evolved over time with the growing scientific understanding of LGBT health needs. Methods This study begins with a review of the early intersections of sexuality and health that led to an LGBT health movement in the United States, as well as the evolution of LGBT health services over time. Informed by this, an asset map displaying the location and types of services provided by “LGBT community health centers” today in relation to the population density of LGBT people was explored. An online search of LGBT community health centers was conducted between September–December, 2015. Organizational details, including physical addresses and the services provided, were confirmed via an online database of federally-registered non-profit organizations and organizational websites. The locations and types of services provided were analyzed and presented alongside county-level census data of same-sex households using geographic information system (GIS) software ArcGIS for Desktop. Findings LGBT community health centers are concentrated within urban hubs and coastal states, and are more likely to be present in areas with a high density of same-sex couples. LGBT community health centers do not operate in 13 states. The most common health services provided are wellness programs, HIV/STI services, and counseling services. Conclusions LGBT community health centers have adapted over time to meet the needs of LGBT people. However, significant gaps in service remain in the United States, and LGBT community health centers may require significant transformations going forward in order to continue serving LGBT people

On the generalized Bykovskii presentation of Steinberg modules

We study presentations of the virtual dualizing modules of special linear groups of number rings, the Steinberg modules. Bykovskii gave a presentation for the Steinberg modules of the integers, and our main result is a generalization of this presentation to the Gaussian integers and the Eisenstein integers. We also show that this generalization does not give a presentation for the Steinberg modules of several Euclidean number rings.Comment: Minor revisions based on referee's comments. Accepted for publication at IMR

The shielding effect extends the lifetimes of two-dimensional sessile droplets

We consider the diffusion-limited evaporation of thin two-dimensional sessile droplets either singly or in a pair. A conformal-mapping technique is used to calculate the vapour concentrations in the surrounding atmosphere, and thus to obtain closed-form solutions for the evolution and the lifetimes of the droplets in various modes of evaporation. These solutions demonstrate that, in contrast to in three dimensions, in large domains the lifetimes of the droplets depend logarithmically on the size of the domain, and more weakly on the mode of evaporation and the separation between the droplets. In particular, they allow us to quantify the shielding effect that the droplets have on each other, and how it extends the lifetimes of the droplets

Cap mesenchyme cell swarming during kidney development is influenced by attraction, repulsion, and adhesion to the ureteric tip

Morphogenesis of the mammalian kidney requires reciprocal interactions between two cellular domains at the periphery of the developing organ: the tips of the epithelial ureteric tree and adjacent regions of cap mesenchyme. While the presence of the cap mesenchyme is essential for ureteric branching, how it is specifically maintained at the tips is unclear. Using ex vivo timelapse imaging we show that cells of the cap mesenchyme are highly motile. Individual cap mesenchyme cells move within and between cap domains. They also attach and detach from the ureteric tip across time. Timelapse tracks collected for >800 cells showed evidence that this movement was largely stochastic, with cell autonomous migration influenced by opposing attractive, repulsive and cell adhesion cues. The resulting swarming behaviour maintains a distinct cap mesenchyme domain while facilitating dynamic remodelling in response to underlying changes in the tip

Generation of human induced pluripotent stem cell-derived cerebral organoids for cellular and molecular characterization

Human induced pluripotent stem cell (hiPSC)-derived cerebral organoids (COs) can serve as a

Elastic instability in stratified core annular flow

We study experimentally the interfacial instability between a layer of dilute polymer solution and water flowing in a thin capillary. The use of microfluidic devices allows us to observe and quantify in great detail the features of the flow. At low velocities, the flow takes the form of a straight jet, while at high velocities, steady or advected wavy jets are produced. We demonstrate that the transition between these flow regimes is purely elastic -- it is caused by viscoelasticity of the polymer solution only. The linear stability analysis of the flow in the short-wave approximation captures quantitatively the flow diagram. Surprisingly, unstable flows are observed for strong velocities, whereas convected flows are observed for low velocities. We demonstrate that this instability can be used to measure rheological properties of dilute polymer solutions that are difficult to assess otherwise.Comment: 4 pages, 4 figure

Tidal breathing parameters measured using structured light plethysmography in healthy children and those with asthma before and after bronchodilator

Structured light plethysmography (SLP) is a light‐based, noncontact technique that measures tidal breathing by monitoring displacements of the thoracoabdominal (TA) wall. We used SLP to measure tidal breathing parameters and their within‐subject variability (v) in 30 children aged 7–16 years with asthma and abnormal spirometry (forced expiratory volume in 1 sec [FEV1] <80% predicted) during a routine clinic appointment. As part of standard care, the reversibility of airway obstruction was assessed by repeating spirometry after administration of an inhaled bronchodilator. In this study, SLP was performed before and after bronchodilator administration, and also once in 41 age‐matched controls. In the asthma group, there was a significant increase in spirometry‐assessed mean FEV1 after administration of bronchodilator. Of all measured tidal breathing parameters, the most informative was the inspiratory to expiratory TA displacement ratio (IE50SLP, calculated as TIF50SLP/TEF50SLP, where TIF50SLP is tidal inspiratory TA displacement rate at 50% of inspiratory displacement and TEF50SLP is tidal expiratory TA displacement rate at 50% of expiratory displacement). Median (m) IE50SLP and its variability (vIE50SLP) were both higher in children with asthma (prebronchodilator) compared with healthy children (mIE50SLP: 1.53 vs. 1.22, P < 0.001; vIE50SLP: 0.63 vs. 0.47, P < 0.001). After administration of bronchodilators to the asthma group, mIE50SLP decreased from 1.53 to 1.45 (P = 0.01) and vIE50SLP decreased from 0.63 to 0.60 (P = 0.04). SLP‐measured tidal breathing parameters could differentiate between children with and without asthma and indicate a response to bronchodilator

Mean-field analysis of a dynamical phase transition in a cellular automaton model for collective motion

A cellular automaton model is presented for random walkers with biologically motivated interactions favoring local alignment and leading to collective motion or swarming behavior. The degree of alignment is controlled by a sensitivity parameter, and a dynamical phase transition exhibiting spontaneous breaking of rotational symmetry occurs at a critical parameter value. The model is analyzed using nonequilibrium mean field theory: Dispersion relations for the critical modes are derived, and a phase diagram is constructed. Mean field predictions for the two critical exponents describing the phase transition as a function of sensitivity and density are obtained analytically.Comment: 4 pages, 4 figures, final version as publishe