Listchristophersen1161
Our key algorithmic innovations include the design of explicit ordinal attention constraints, enabling principled model training in a weakly-supervised fashion, while also facilitating the generation of visual-attention-driven model explanations by means of localization cues. On two large-scale chest X-ray datasets (NIH ChestX-ray14 and CheXpert), we demonstrate significant localization performance improvements over the current state of the art while also achieving competitive classification performance.Multi-compartment models (MCM) are increasingly used to characterize the brain white matter microstructure from diffusion-weighted imaging (DWI). Their use in clinical studies is however limited by the inability to resample an MCM image towards a common reference frame, or to construct atlases from such brain microstructure models. We propose to solve this problem by first identifying that these two tasks amount to the same problem. We propose to tackle it by viewing it as a simplification problem, solved thanks to spectral clustering and the definition of semi-metrics between several usual compartments encountered in the MCM literature. This generic framework is evaluated for two models the multi-tensor model where individual fibers are modeled as individual tensors and the diffusion direction imaging (DDI) model that differentiates intra- and extra-axonal components of each fiber. Results on simulated data, simulated transformations and real data show the ability of our method to well interpolate MCM images of these types. We finally present as an application an MCM template of normal controls constructed using our approach.Positron emission tomography (PET) is widely used for clinical diagnosis. As PET suffers from low resolution and high noise, numerous efforts try to incorporate anatomical priors into PET image reconstruction, especially with the development of hybrid PET/CT and PET/MRI systems. In this work, we proposed a cube-based 3D structural convolutional sparse coding (CSC) concept for penalized-likelihood PET image reconstruction, named 3D PET-CSC. selleck chemicals The proposed 3D PET-CSC takes advantage of the convolutional operation and manages to incorporate anatomical priors without the need of registration or supervised training. As 3D PET-CSC codes the whole 3D PET image, instead of patches, it alleviates the staircase artifacts commonly presented in traditional patch-based sparse coding methods. Compared with traditional coding methods in Fourier domain, the proposed method extends the 3D CSC to a straightforward approach based on the pursuit of localized cubes. Moreover, we developed the residual-image and order-subset mechanisms to further reduce the computational cost and accelerate the convergence for the proposed 3D PET-CSC method. Experiments based on computer simulations and clinical datasets demonstrate the superiority of 3D PET-CSC compared with other reference methods.Background Sexualised drug use has attracted interest due to the role it could play in increasing exposure to the transmission of HIV and other sexually transmissible infections. It also carries risks inherent to substance use and may influence psychosocial factors. This study characterised sexualised drug use among Latin America MSM Internet Survey (LAMIS) respondents in Chile, in order to identify aspects associated with the phenomenon.
LAMIS data were used to analyse drug use (in any context, in sexual context and sexualised drug use), epidemiological aspects and psychosocial aspects. In addition, the associations between the sexualised drug use and these aspects were estimated.
The prevalence of sexualised drug use was 24% (n = 4945). The drugs most used in a sexual context (n = 3365) were cannabis, poppers and viagra. Cocaine, ecstasy/MDMA (3,4-Methylenedioxymethamphetamine) and ketamine use were reported in sexual encounters with multiple partners. Living with HIV (adjusted odds ratio (AOR) = 1.92), having had sex with three or more casual partners in the past year (AOR = 2.02) and having engaged in sex without a condom with three or more casual partners in this period (AOR = 1.61) were aspects associated with sexualised drug use. Less social integration (AOR = 0.76) and internalised homonegativity (AOR = 0.85) were aspects associated with a decrease of possibility of practising sexual drug use.
Sexualised drug use is an emerging phenomenon in Chile, whose complexity needs to be studied in all its dimensions to have a complete understanding of its effect on people's health.
Sexualised drug use is an emerging phenomenon in Chile, whose complexity needs to be studied in all its dimensions to have a complete understanding of its effect on people's health.Agricultural workers are exposed to solar ultraviolet (UV) radiation due to the significant amount of time spent working outdoors. Risk information on UV exposure from the EPA SunWise UV Index mobile app is conveniently available for timely advice on risk management, but its reliability is unknown. The purpose of this study was to determine the reliability of the EPA UV Index app in providing accurate risk information to reduce UV exposure and prevent related illnesses among agricultural workers in eastern North Carolina. UV radiation effective irradiance (UV eff ) indices were datalogged at two agricultural sites using radiometers from April-August 2019 and were assigned to risk levels (low, moderate, high, very high, extreme) based on the ACGIH® Threshold Limit Values (TLVs®). The UV index (UV app ) and its corresponding risk level were obtained using the app. Hourly UV app -based risk level assignments were time-matched to their corresponding UV eff /TLV-based risk level assignments (871 pairs) and analyzeexposure in agricultural settings is not recommended.Nanoporous oxides have been prepared, as hosts for the encapsulation of metal nanoparticles, and tested for the catalytic decomposition of methylcyclohexane (MCH) to produce hydrogen gas as a potential fuel source. The aim of the work is to test a range of mixed metal nanoparticle catalysts in the MCH to hydrogen reaction. The work investigates the use of a range of inexpensive metals in conjunction with traditional precious metal e.g. Pt. The objectives of work are prepared nanoporous oxides, comprising MCM- and SBA-types using established methods. Encapsulated metal nanoparticles within the pores of nanoporous oxide. Catalysts have been characterized fully to confirm porosity, surface area, and nanoparticle dispersion. The activity of catalytic of the various nanoporous materials was determined in the MCH to hydrogen reaction, and kinetic models developed from the associated experimental findings.