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  1. This research investigates the effect of scaling in virtual reality to improve the reach of users with Parkinson’s disease (PD). People with PD have limited reach, often due to impaired postural stability. We investigated how virtual reality (VR) can improve reach during and after VR exposure. Participants played a VR game where they smashed water balloons thrown at them by crossing their midsection. The distance the balloons were thrown at increased and decreased based on success or failure. Their perception of the distance and their hand were scaled in three counterbalanced conditions: under-scaled (scale = 0:83), not-scaled (scale = 1), and over-scaled (scale = 1:2), where the scale value is the ratio between the virtual reach that they perceive in the virtual environment (VE) and their actual reach. In each study condition, six data were measured - 1. Real World Reach (pre-exposure), 2. Virtual Reality Baseline Reach, 3. Virtual Reality Not-Scaled Reach, 4. Under-Scaled Reach, 5. Over-Scaled Reach, and 6. Real World Reach (post-exposure). Our results show that scaling a person’s movement in virtual reality can help improve reach. Therefore, we recommend including a scaling factor in VR games for people with Parkinson’s disease.
  2. Free, publicly-accessible full text available January 1, 2024
  3. Abstract The semiconductor tracker (SCT) is one of the tracking systems for charged particles in the ATLAS detector. It consists of 4088 silicon strip sensor modules.During Run 2 (2015–2018) the Large Hadron Collider delivered an integrated luminosity of 156 fb -1 to the ATLAS experiment at a centre-of-mass proton-proton collision energy of 13 TeV. The instantaneous luminosity and pile-up conditions were far in excess of those assumed in the original design of the SCT detector.Due to improvements to the data acquisition system, the SCT operated stably throughout Run 2.It was available for 99.9% of the integrated luminosity and achieved a data-quality efficiency of 99.85%.Detailed studies have been made of the leakage current in SCT modules and the evolution of the full depletion voltage, which are used to study the impact of radiation damage to the modules.
  4. Abstract

    Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressingE. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals  <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.