Magnetic Field and Plasma Observations at Mars: Initial Results of the Mars Global Surveyor Mission

The magnetometer and electron reflectometer investigation (MAG/ER) on the Mars Global Surveyor spacecraft has obtained magnetic field and plasma observations throughout the near-Mars environment, from beyond the influence of Mars to just above the surface (at an altitude of approximately 100 kilometers). The solar wind interaction with Mars is in many ways similar to that at Venus and at an active comet, that is, primarily an ionospheric-atmospheric interaction. No significant planetary magnetic field of global scale has been detected to date (<2 x 10(21) Gauss-cubic centimeter), but here the discovery of multiple magnetic anomalies of small spatial scale in the crust of Mars is reported.

International Cancer Genome Consortium Data Portal--a one-stop shop for cancer genomics data

The International Cancer Genome Consortium (ICGC) is a collaborative effort to characterize genomic abnormalities in 50 different cancer types. To make this data available, the ICGC has created the ICGC Data Portal. Powered by the BioMart software, the Data Portal allows each ICGC member institution to manage and maintain its own databases locally, while seamlessly presenting all the data in a single access point for users. The Data Portal currently contains data from 24 cancer projects, including ICGC, The Cancer Genome Atlas (TCGA), Johns Hopkins University, and the Tumor Sequencing Project. It consists of 3478 genomes and 13 cancer types and subtypes. Available open access data types include simple somatic mutations, copy number alterations, structural rearrangements, gene expression, microRNAs, DNA methylation and exon junctions. Additionally, simple germline variations are available as controlled access data. The Data Portal uses a web-based graphical user interface (GUI) to offer researchers multiple ways to quickly and easily search and analyze the available data. The web interface can assist in constructing complicated queries across multiple data sets. Several application programming interfaces are also available for programmatic access. Here we describe the organization, functionality, and capabilities of the ICGC Data Portal.

Therapeutic efficacy of intra-cochlear administration of methylprednisolone after acoustic trauma caused by gunshot noise in guinea pigs

The therapeutic efficacy of cochlear infusion of methylprednisolone (MP) after an impulse noise trauma (170dB SPL peak) was evaluated in guinea pigs. The compound action potential threshold shifts were measured over a 14 days recovery period after the gunshot exposure. For each animal, one of the cochlea was perfused directly into the scala tympani with MP during 7 days via a mini-osmotic pump, whereas the other cochlea was not pump-implanted. The functional study of hearing was supplemented by histological analysis. Forty eight hours after the trauma, significant differences between auditory threshold shifts in the implanted and non-implanted ears were observed for frequencies above 8kHz. At day 7, the difference was significant for only one frequency and no difference was observed after 14 days recovery. Cochleograms showed that the hair cell losses were significantly lower in the MP treated ears. This work indicates that direct infusion of MP into perilymphatic space accelerates hearing recovery, reduces hair cell losses after impulse noise trauma but does not limit permanent threshold shifts.

Perspectives of injectable long acting antiretroviral therapies for HIV treatment or prevention: understanding potential users' ambivalences

Recent clinical trial data showed that injectable long-acting antiretroviral treatment (LA-ART) every four or eight weeks could become an alternative option for HIV treatment or prevention. The purpose of our study was to explore perceptions and potential users' points of views of this new mode of administration through individuals' therapeutic itinerary and their singular history with ART. Between 2018 and 2019, a qualitative study was conducted in two University Hospitals in Paris, France. In-depth interviews were conducted with 15 virologically controlled People Living with HIV (PLWH) and 13 men on pre-exposure prophylaxis (PrEP) for at least six months. Interviews, focused on the daily experience with ART, were recorded, transcribed, and analyzed using thematic content analysis. Collected discourses were organized around three emergent concerns: social, material and experimental. Each of these concerns was perceived as ambivalent, balanced by skepticism and hope. It revealed the complexity of each individual's relationship to their HIV treatment or PrEP, leading to balance the injectable LA-ART popularity reported within clinical trials. This new mode of administration may be a suitable alternative for some PLWH and PrEP users, a "simplification" compared to the oral route. It opens a window for "customizable" ART-treatment according to individuals' lives.

Growth, structural and optical properties of AlGaN nanowires in the whole composition range

We report on the growth of AlxGa1-xN nanowires by plasma-assisted molecular beam epitaxy for x in the 0.3-0.8 range. Based on a combination of macro- and micro-photoluminescence, Raman spectroscopy, x-ray diffraction and scanning electron microscopy experiments, it is shown that the structural and optical properties of AlGaN NWs are governed by the presence of compositional fluctuations associated with strongly localized electronic states. A growth model is proposed, which suggests that, depending on growth temperature and metal adatom density, macroscopic composition fluctuations are mostly of kinetic origin and are directly related to the nucleation of the AlGaN nanowire section on top of the GaN nanowire base which is used as a substrate.

Diagnosis, risk factors and management of diabetes mellitus in HIV-infected persons in France: A real-life setting study

BACKGROUND

Diabetes mellitus (DM) is a major and increasing public health problem that may be underdiagnosed and undertreated among persons living with HIV (PLWH).

OBJECTIVE

To describe the diagnosis, treatment and follow-up of DM among PLWH.

METHODS

This study was performed inside a monocentric cohort of 1494 PLWH. DM was defined as having a FG ≥126 mg/dL twice or a HbA1c ≥6.5%, or a history of diabetes, or receiving antidiabetic treatment. The first visit mentioning a diagnosis of DM was considered as the baseline visit. Chi-Square or Fisher exact test were used to examine the association between categorical variables and DM, Wilcoxon or Student t-test were used for continuous variables.

RESULTS

156 PLWH with DM were included. Compared to non-diabetic participants, they were more likely to be native of Sub Saharan Africa (31.6% vs. 22.4%, p = 0.027) and older (54.6 vs. 49.9 years, p<0.001), to have a higher BMI (> 25 for 46.1% vs. 35.3%, p = 0.020) and a poorer control of HIV (HIV RNA<50 copies/mL: 80.1% vs. 89.5%, p<0.001). The diagnosis of DM was missed in 37.8% of PLWH, and 47.2% of PLWH treated for DM did not reach a HbA1c<7%. PLWH with DM were more frequently on antihypertensive and/or lipid-lowering medications: 94.2% had a LDL-cholesterol <70 mg/dL and 60.9% had a blood pressure <140/90 mmHg.

CONCLUSION

In a setting of HIV-control, HIV care providers should focus on metabolic issues. The management of DM and associated risk factors is mandatory to prevent cardiovascular disease in PLWH.

Injectable long acting antiretroviral for HIV treatment and prevention: perspectives of potential users

BACKGROUND

The use of long acting injectable (LAA) antiretroviral drugs may be an alternative option for HIV treatment and prevention. Our study focused on patient perspectives to understand which individuals, among people with HIV (PWH) and pre-exposure prophylaxis (PrEP) users, would constitute the preferential target for such treatments in terms of expectations, tolerability, adherence and quality of life.

METHODS

The study consisted in one self-administrated questionnaire. Data collected included lifestyle issues, medical history, perceived benefits and inconveniences of LAA. Groups were compared using Wilcoxon rank tests or Fisher's exact test.

RESULTS

In 2018, 100 PWH and 100 PrEP users were enrolled. Overall, 74% of PWH and 89% of PrEP users expressed interest for LAA with a significantly higher rate for PrEP users (p = 0.001). No characteristics were associated with acceptance of LAA in both groups in term of demographics, lifestyle or comorbidities.

CONCLUSION

PWH and PrEP users expressed a high level of interest in LAA, since a large majority seems to be in favor of this new approach. Further studies should be conducted to better characterize targeted individuals.

Assessment of Polarity in GaN Self-Assembled Nanowires by Electrical Force Microscopy

In this work, we demonstrate the capabilities of atomic force microscopies (AFMs) for the nondestructive determination of the polarity of GaN nanowires (NWs). Three complementary AFMs are analyzed here: Kelvin probe force microscopy (KPFM), light-assisted KPFM, and piezo-force microscopy (PFM). These techniques allow us to assess the polarity of individual NWs over an area of tens of μm(2) and provide statistics on the polarity of the ensemble with an accuracy hardly reachable by other methods. The precise quantitative analysis of the tip-sample interaction by multidimensional spectroscopic measurements, combined with advanced data analysis, has allowed the separate characterization of electrostatic and van der Waals forces as a function of tip-sample distance. Besides their polarity, the net surface charge density of individual NWs was estimated.