Flexible Group Fairness Metrics for Survival Analysis

Algorithmic fairness is an increasingly important field concerned with detecting and mitigating biases in machine learning models. There has been a wealth of literature for algorithmic fairness in regression and classification however there has been little exploration of the field for survival analysis. Survival analysis is the prediction task in which one attempts to predict the probability of an event occurring over time. Survival predictions are particularly important in sensitive settings such as when utilising machine learning for diagnosis and prognosis of patients. In this paper we explore how to utilise existing survival metrics to measure bias with group fairness metrics. We explore this in an empirical experiment with 29 survival datasets and 8 measures. We find that measures of discrimination are able to capture bias well whereas there is less clarity with measures of calibration and scoring rules. We suggest further areas for research including prediction-based fairness metrics for distribution predictions.Comment: Accepted in DSHealth 2022 (Workshop on Applied Data Science for Healthcare

Consensus Paper: Radiological Biomarkers of Cerebellar Diseases

Hereditary and sporadic cerebellar ataxias represent a vast and still growing group of diseases whose diagnosis and differentiation cannot only rely on clinical evaluation. Brain imaging including magnetic resonance (MR) and nuclear medicine techniques allows for characterization of structural and functional abnormalities underlying symptomatic ataxias. These methods thus constitute a potential source of radiological biomarkers, which could be used to identify these diseases and differentiate subgroups of them, and to assess their severity and their evolution. Such biomarkers mainly comprise qualitative and quantitative data obtained from MR including proton spectroscopy, diffusion imaging, tractography, voxel-based morphometry, functional imaging during task execution or in a resting state, and from SPETC and PET with several radiotracers. In the current article, we aim to illustrate briefly some applications of these neuroimaging tools to evaluation of cerebellar disorders such as inherited cerebellar ataxia, fetal developmental malformations, and immune-mediated cerebellar diseases and of neurodegenerative or early-developing diseases, such as dementia and autism in which cerebellar involvement is an emerging feature. Although these radiological biomarkers appear promising and helpful to better understand ataxia-related anatomical and physiological impairments, to date, very few of them have turned out to be specific for a given ataxia with atrophy of the cerebellar system being the main and the most usual alteration being observed. Consequently, much remains to be done to establish sensitivity, specificity, and reproducibility of available MR and nuclear medicine features as diagnostic, progression and surrogate biomarkers in clinical routine

ISSN exercise & sport nutrition review: research & recommendations

Sports nutrition is a constantly evolving field with hundreds of research papers published annually. For this reason, keeping up to date with the literature is often difficult. This paper is a five year update of the sports nutrition review article published as the lead paper to launch the JISSN in 2004 and presents a well-referenced overview of the current state of the science related to how to optimize training and athletic performance through nutrition. More specifically, this paper provides an overview of: 1.) The definitional category of ergogenic aids and dietary supplements; 2.) How dietary supplements are legally regulated; 3.) How to evaluate the scientific merit of nutritional supplements; 4.) General nutritional strategies to optimize performance and enhance recovery; and, 5.) An overview of our current understanding of the ergogenic value of nutrition and dietary supplementation in regards to weight gain, weight loss, and performance enhancement. Our hope is that ISSN members and individuals interested in sports nutrition find this review useful in their daily practice and consultation with their clients

hrbrmstr/hrbrthemes: Dark Matter

theme_ft_rc() a new dark theme in loving homage to the Financial Times design team Under-the-hood tweaks & documentation cleanu

A freestanding photoswitchable aero-polymer with an incorporated bridged azobenzene: 3D structure, photoinduced motion, biocompatibility and potential application as photomechanical cell scaffold

Photoswitchable polymers are of great interest for a variety of applications such as optical data storage, functional membranes and photoactuators. The latter are typically fabricated by wet-chemical approaches including gels, liquid-crystalline elastomers and supramolecular polymers. In this work we demonstrate the fabrication of a new freestanding photoswitchable aeropolymer-structure via solvent-free, single-step initiated chemical vapor deposition (iCVD) using tetrapodal zinc oxide (t-ZnO) as sacrificial substrate material. On the molecular scale, the copolymer is composed of 2-hydroxyethyl methacrylate (HEMA) and a specifically synthesized diazocine (a bridged azobenzene) as photoswitchable cross-linking unit. iCVD enables in this connection a combination of both comonomers while preserving their chemical functionalities as well as the individual structure of the t-ZnO templates without pore clogging. After post-reactional etching and drying, a hollow polymer network with nanoscopic thin walls remains maintaining the substrate characteristic tetrapodal structure, which we coined aero-photoswitch. We identify and differentiate specific properties of the fabricated structures, originating from the switchable copolymer and the highly porous tetrapodal conformation, for a comprehensive description of the overall aero-structures. These aero-photoswitchable polymers provide unique properties due to their extremely delicate yet stable morphology and their efficient transformation of molecular photoisomerization to motion on the macroscopic scale upon illumination with blue light. In addition, we investigate their biocompatibility as well as successful cell attachment and proliferation. These new photoswitchable actuators turn out to be highly promising smart materials for future research on photoswitchable scaffolds