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An interesting opportunity offered by the detection of stellar oscillations is the possibility to infer the internal rotation rate of a star through the so-called rotational splittings. Such seismic measurements remained rather scarce for hot B subdwarf (sdB) stars until the advent of space observations with the Kepler spacecraft. Nowadays, however, a number of rotation measurements have become available, offering a glimpse on the global rotational properties of sdB stars. Here, we briefly discuss what asteroseismology starts to reveal on the rotation rate of these stars. We also make connections with the internal rotation of red-giant and white-dwarf stars. In particular, we show that the very slow rotation rates derived for single sdB stars, and their similarities with the dynamical properties of the cores of red-clump stars, strongly suggest that they evolved from red-giants rather than merger events.We also point out that no more angular momentum seems to be lost by stellar cores throughout the helium burning phase until the cooling white-dwarf stage, indicating that all the braking occurs before, most likely during red-giant branch evolution.

We present a new asteroseismic modeling of the hot B subdwarf (sdB) pulsator PG 1219+534, based on a 3- month campaign with the Mont4K/Kuiper combination at Mt Bigelow (Arizona) and on updated atmospheric parameters from high S/N low and medium resolution spectroscopy. On the basis of the nine independent pulsation periods extracted from the photometric light curve, we carried out an astroseismic analysis by applying the forward modeling approach using our latest (third and fourth generation) sdB models. Atmospheric parameters (Teff = 34 258 ± 170 K, log g = 5.838 ± 0.030) were used as independent constraints, as well as partial mode identification based on observed multiplet structures we ascribed to stellar rotation. The optimal model found is remarkably consistent between various analyses with third and fourth generation of sdB models, and also with previously published analysis with second generation sdB models. It corresponds to a sdB with a canonical mass (0.46 ± 0.02 M⊙), rather thin H-He envelope (log q(envl) = −3.75 ± 0.12), and close to He-burning exhaustion (Xcore(C + O) = 0.86 ± 0.05).We also investigate the internal rotation of the star.We find that PG 1219+534 rotates very slowly (Prot = 34.91 ± 0.84 days) and that solid-body rotation is reached at least down to ∼60% of the radius.

Phalloplasties are one of the most performed genital surgeries in the treatment of gender dysphoria for transmasculine patients. Urethral lengthening is an essential component of phalloplasties. Few techniques have been described for the creation of this pars fixa urethra. The purpose of this article is to present the Montréal Classification for pars fixa urethral lengthening, to detail the surgical techniques and to report on clinical outcomes. All patients undergoing phalloplasty from November 2016 to February 2019 were included in this study. Patient demographics, type of surgery and urological complications were recorded. Statistics were performed using student's T-test, Chi-squared test, Fisher's exact test and One-way ANOVA. Patients underwent either type 1, type 2, or type 3 urethral reconstruction. Of the 84 total patients, 45 underwent type 1 lengthening, 28 type 2, and 11 type 3. Eighteen and 33 patients underwent single-stage and two stage anastomosis of the pars fixa to the pars pendulans neourethra, respectively. Thirty-three patients have not had any additional surgeries to date. Post-operative urological complications for immediate anastomosis and two-stage anastomosis were reported in 77.7% and 18.2% of patients, respectively. We propose a classification as well as a description of three types of urethral lengthening techniques. Over the last few years, we have shifted away from single-stage anastomosis and have adopted a two-stage anastomosis technique. Our experience allows us to classify urethral lengthening and to standardize care depending on patient characteristics, leading to excellent results. [ABSTRACT FROM AUTHOR]

We present a new asteroseismic modeling of the hot B subdwarf (sdB) pulsator PG 1219+534, based on a 3- month campaign with the Mont4K/Kuiper combination at Mt Bigelow (Arizona) and on updated atmospheric parameters from high S/N low and medium resolution spectroscopy. On the basis of the nine independent pulsation periods extracted from the photometric light curve, we carried out an astroseismic analysis by applying the forward modeling approach using our latest (third and fourth generation) sdB models. Atmospheric parameters (Teff = 34 258 ± 170 K, log g = 5.838 ± 0.030) were used as independent constraints, as well as partial mode identification based on observed multiplet structures we ascribed to stellar rotation. The optimal model found is remarkably consistent between various analyses with third and fourth generation of sdB models, and also with previously published analysis with second generation sdB models. It corresponds to a sdB with a canonical mass (0.46 ± 0.02 M⊙), rather thin H-He envelope (log q(envl) = −3.75 ± 0.12), and close to He-burning exhaustion (Xcore(C + O) = 0.86 ± 0.05).We also investigate the internal rotation of the star.We find that PG 1219+534 rotates very slowly (Prot = 34.91 ± 0.84 days) and that solid-body rotation is reached at least down to ∼60% of the radius. [ABSTRACT FROM AUTHOR]

An interesting opportunity offered by the detection of stellar oscillations is the possibility to infer the internal rotation rate of a star through the so-called rotational splittings. Such seismic measurements remained rather scarce for hot B subdwarf (sdB) stars until the advent of space observations with the Kepler spacecraft. Nowadays, however, a number of rotation measurements have become available, offering a glimpse on the global rotational properties of sdB stars. Here, we briefly discuss what asteroseismology starts to reveal on the rotation rate of these stars. We also make connections with the internal rotation of red-giant and white-dwarf stars. In particular, we show that the very slow rotation rates derived for single sdB stars, and their similarities with the dynamical properties of the cores of red-clump stars, strongly suggest that they evolved from red-giants rather than merger events.We also point out that no more angular momentum seems to be lost by stellar cores throughout the helium burning phase until the cooling white-dwarf stage, indicating that all the braking occurs before, most likely during red-giant branch evolution. [ABSTRACT FROM AUTHOR]

Objectives: The testes are a potential viral sanctuary site for HIV-1 infection. Our study aims to provide insight into the expression and localization of key drug transporters and metabolic enzymes relevant to ART in this tissue compartment.Methods: We characterized gene and protein expression of 12 representative drug transporters and two metabolic enzymes in testicular tissue samples obtained from uninfected (n = 8) and virally suppressed HIV-1-infected subjects on ART (n = 5) and quantified antiretroviral drug concentrations in plasma and testicular tissues using LC/MS/MS from HIV-1-infected subjects.Results: Our data demonstrate that key ABC drug transporters (permeability glycoprotein, multidrug-resistance protein 1, 2 and 4, and breast cancer resistance protein), solute carrier transporters (organic anion transporting polypeptides 1B1 and 2B1, organic anion transporter 1, concentrative nucleoside transporter 1, equilibrative nucleoside transporter 2) and cytochrome P450 metabolic enzymes (CYP3A4 and CYP2D6) previously shown to interact with many commonly used antiretroviral drugs are expressed at the mRNA and protein level in the testes of both subject groups and localize primarily at the blood-testis barrier, with no significant differences between the two groups. Furthermore, we observed that PIs known to be substrates for ATP-binding cassette membrane transporters, displayed variable testicular tissue penetration, with darunavir concentrations falling below therapeutic values. In contrast, the NRTIs emtricitabine, lamivudine and tenofovir displayed favourable tissue penetration, reaching concentrations comparable to plasma levels. We also demonstrated that nuclear receptors, peroxisome proliferator-activated receptors α and γ exhibited higher gene expression in the testicular tissue compared with pregnane X receptor and constitutive androstane receptor, suggesting a potential regulatory pathway governing drug transporter and metabolic enzyme expression in this tissue compartment.Conclusions: Our data suggest the testes are a complex pharmacological compartment that can restrict the distribution of certain antiretroviral drugs and potentially contribute to HIV-1 persistence. [ABSTRACT FROM AUTHOR]

We present a brief progress report in our quest for deriving seismic models of pulsating white dwarfs that can account simultaneously for all the observed periods at the precision of the observations. We point out that this is possible from a pratical point of view only if parametrized models are used to complement evolutionary models. We adopt a double optimization procedure that insures that the best possible model in parameter space is found objectively and automatically. Our ultimate goal is to be able to account for the exquisite period data gathered with Kepler and Kepler-2 on key pulsating white dwarfs of both the DA (ZZ Ceti) and DB (V777 Her) type. [ABSTRACT FROM PUBLISHER]

Presents results of a study that examines diffusion and binding of protons in sediments. Transport and exchange of metals in natural waters; Measurement of metal and proton binding on sediments by a titration done at equilibrium; Optimization parameters.

Hamilton Harbour sediments are elevated in metal and organic contaminants, resulting from 75 years of industrial and municipal discharge.These contaminants could be released from the sediments during resuspension events caused by strong winds or dredging operations. We predict the metal concentrations in the water column that would be found during resuspension, using an equilibrium adsorption model. Confirmation of the model was made experimentally using small reactors with spikes of metal added to the aqueous phase. Four different Hamilton Harbour sites were sampled and used in the experiments. The time to reach steady state was determined as 2 days or less after the resuspension event. Results from the experiments yielded aqueous phase concentrations equivalent to or lower than concentrations in Hamilton Harbour water. We conclude that the concentration of metals in the water column of Hamilton Harbour is not elevated by resuspension of surficial sediments. [ABSTRACT FROM AUTHOR]

The size distribution of sediments in Hamilton Harbour is a result of both natural and human processes. The objective is to predict the behavior of sediment particles in the harbor, assuming wind driven resuspension to be the major natural factor controlling grain size distribution. In this approach hydraulic sorting of sediments was assumed to be entirely predictable from 10 years of wind direction and velocity data used to calculate fetch over the extent of the harbor. Bottomvelocities were estimated assuming a universal velocity defect law and the direction of bottom currents were assumed to parallel the depth contours. Although simplistic in many regards, the model returns adjustment parameters that are consistent with accepted values and is sufficiently articulated to be used as a reference to evaluate the cause of sediment transport in the harbor. Known local disturbances associated with human activity in the harbor could be predicted by mapping the differences between sediment distribution and actual core data from surficial sediments. A large part of the sediment in the deeper part of the harbor, however, contained more silt and clays than predicted. We assume this excess to be caused by a uniform disturbance equivalent to a 4.8 cm/sec bottom current and results from the combination of small bottom currents and other transfers of energy from the mixed layer. Historical records show that this situation existed long before the industrial period. Man-made disturbances on the overall distribution of bottom sediments are therefore less important compared to changes due to agricultural practices at the turn of the century. [ABSTRACT FROM AUTHOR]

HIV's ability to persist during suppressive antiretroviral therapy is the main barrier to cure. Immune privileged tissues such as the testes may constitute distinctive sites of HIV persistence, but this has been challenging to study in humans. We analyzed proviral burden and genetics in blood and testes of 10 individuals on suppressive therapy who underwent elective gender affirming surgery. HIV DNA levels in matched blood and testes were quantified by qPCR and subgenomic proviral sequences (nef region) were characterized from single templates. HIV diversity, compartmentalization and immune escape burden were assessed using genetic and phylogenetic approaches. Diverse proviruses were recovered from blood (396 sequences; 354 nef-intact) and testes (326 sequences; 309 nef-intact) of all participants. Notably, the frequency of identical HIV sequences varied markedly between and within individuals. Nevertheless, proviral loads, within-host unique HIV sequence diversity, and immune escape burden correlated positively between blood and testes. When all intact nef sequences were evaluated, 60% of participants exhibited significant blood-testes genetic compartmentalization, but none did so when restricting to unique sequences per site, suggesting that compartmentalization, when present, is attributable to clonal expansion of HIV-infected cells. Our observations confirm the testes as a site of HIV persistence and suggest that individuals with larger and more diverse blood reservoirs will have larger and more diverse testes reservoirs. Furthermore, while the testes microenvironment may not be sufficiently unique to facilitate the seeding of unique viral populations therein, differential clonal expansion dynamics may be at play, which may complicate HIV eradication. [ABSTRACT FROM AUTHOR]

Background: Little is known about the prevalence of testicular cancer in the transfeminine population. Only six cases have been reported in the literature. This case series reports six additional cases of various testicular cancers found in transfeminine patients who underwent vaginoplasty with orchidectomy in our institution., Methods: In our institution, all specimens are routinely sent to pathology following vaginoplasty with orchidectomy. This permitted the identification of all positive cases of testicular cancer. A chart review was conducted to retrieve patient demographics, duration of hormonotherapy, type of neoplasm, the context of its discovery, and cancer follow-up., Results: A total of 2555 patients underwent vaginoplasty with orchidectomy between January 2016 and January 2021. All specimens were sent to pathology for analysis. A total of six (0.23% of patients) specimens revealed malignant lesions., Conclusions: Increased societal awareness toward the transgender population encourages recourse to gender-affirming procedures. Little is known about the incidence of testicular cancer in the transfeminine population. In total, 0.23% of patients in our cohort presented with positive pathology findings indicative of testicular cancer. All cancers were found to be only locally invasive, and all patients were successfully treated. We therefore encourage routine pathology examination for all specimens following vaginoplasty with orchidectomy., (Copyright © 2022 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of The American Society of Plastic Surgeons.)