205 research outputs found
A portable laser system for high precision atom interferometry experiments
We present a modular rack-mounted laser system for the cooling and
manipulation of neutral rubidium atoms which has been developed for a portable
gravimeter based on atom interferometry that will be capable of performing high
precision gravity measurements directly at sites of geophysical interest. This
laser system is constructed in a compact and mobile design so that it can be
transported to different locations, yet it still offers improvements over many
conventional laboratory-based laser systems. Our system is contained in a
standard 19" rack and emits light at five different frequencies simultaneously
on up to 12 fibre ports at a total output power of 800 mW. These frequencies
can be changed and switched between ports in less than a microsecond. The setup
includes two phase-locked diode lasers with a phase noise spectral density of
less than 1 \mu rad/sqrt(Hz) in the frequency range in which our gravimeter is
most sensitive to noise. We characterize this laser system and evaluate the
performance limits it imposes on an interferometer.Comment: 8 pages, 11 figures; The final publication is available at
http://www.springerlink.co
Home Is Where the Smart Is: Development and Validation of the Cybersecurity Self-Efficacy in Smart Homes (CySESH) Scale
The ubiquity of devices connected to the internet raises concerns about the security and privacy of smart homes. The effectiveness of interventions to support secure user behaviors is limited by a lack of validated instruments to measure relevant psychological constructs, such as self-efficacy - the belief that one is able to perform certain behaviors. We developed and validated the Cybersecurity Self-Efficacy in Smart Homes (CySESH) scale, a 12-item unidimensional measure of domain-specific self-efficacy beliefs, across five studies (N = 1247). Three pilot studies generated and refined an item pool. We report evidence from one initial and one major, preregistered validation study for (1) excellent reliability (α = 0.90), (2) convergent validity with self-efficacy in information security (rSEIS = 0.64, p < .001), and (3) discriminant validity with outcome expectations (rOE = 0.26, p < .001), self-esteem (rRSE = 0.17, p < .001), and optimism (rLOT-R = 0.18, p < .001). We discuss CySESH's potential to advance future HCI research on cybersecurity, practitioner user assessments, and implications for consumer protection policy
4.2 Summary of an ICPPR Non-Apis workshop – Subgroup higher tier (bumble bees and solitary bees) with recommendations for a semi-field experimental design
Risk of cutaneous squamous cell carcinoma due to occupational exposure to solar ultraviolet radiation: Protocol for a systematic review and meta-analysis
: Solar ultraviolet radiation (UVR) is the most significant occupational carcinogenic exposure in terms of the number of workers exposed (i.e., outdoor workers). Consequently, solar UVR-induced skin cancers are among the most common forms of occupational malignancies that are potentially expected globally. This systematic review is registered in PROSPERO (CRD42021295221) and aims to assess the risk of cutaneous squamous cell carcinoma (cSCC) associated to occupational solar UVR exposure. Systematic searches will be performed in three electronic literature databases (PubMed/Medline, EMBASE, and Scopus). Further references will be retrieved by a manual search (e.g., in grey literature databases, internet search engines, and organizational websites). We will include cohort studies and case-control studies. Risk of Bias assessment will be conducted separately for case-control and cohort studies. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) will be used for the certainty of assessment. In case quantitative pooling is not feasible, a narrative synthesis of results will be performed
Experimental assessment of inter-centre variation in stopping-power and range prediction in particle therapy
Purpose: Experimental assessment of inter-centre variation and absolute accuracy of stopping-power ratio (SPR) prediction within 17 particle therapy centres of the European Particle Therapy Network. Material and methods: A head and body phantom with seventeen tissue-equivalent materials were scanned consecutively at the participating centres using their individual clinical CT scan protocol and translated into SPR with their in-house CT-number-to-SPR conversion. Inter-centre variation and absolute accuracy in SPR prediction were quantified for three tissue groups: lung, soft tissues and bones. The integral effect on range prediction for typical clinical beams traversing different tissues was determined for representative beam paths for the treatment of primary brain tumours as well as lung and prostate cancer. Results: An inter-centre variation in SPR prediction (2 sigma) of 8.7%, 6.3% and 1.5% relative to water was determined for bone, lung and soft-tissue surrogates in the head setup, respectively. Slightly smaller variations were observed in the body phantom (6.2%, 3.1%, 1.3%). This translated into inter-centre variation of integral range prediction (2 sigma) of 2.9%, 2.6% and 1.3% for typical beam paths of prostate-, lung-and primary brain-tumour treatments, respectively. The absolute error in range exceeded 2% in every fourth participating centre. The consideration of beam hardening and the execution of an independent HLUT validation had a positive effect, on average. Conclusion: The large inter-centre variations in SPR and range prediction justify the currently clinically used margins accounting for range uncertainty, which are of the same magnitude as the inter-centre variation. This study underlines the necessity of higher standardisation in CT-number-to-SPR conversion. (C) 2021 The Authors. Published by Elsevier B.V
Arterial hypertension and β-amyloid accumulation have spatially overlapping effects on posterior white matter hyperintensity volume: a cross-sectional study
BackgroundWhite matter hyperintensities (WMH) in subjects across the Alzheimer's disease (AD) spectrum with minimal vascular pathology suggests that amyloid pathology-not just arterial hypertension-impacts WMH, which in turn adversely influences cognition. Here we seek to determine the effect of both hypertension and A beta positivity on WMH, and their impact on cognition.MethodsWe analysed data from subjects with a low vascular profile and normal cognition (NC), subjective cognitive decline (SCD), and amnestic mild cognitive impairment (MCI) enrolled in the ongoing observational multicentre DZNE Longitudinal Cognitive Impairment and Dementia Study (n = 375, median age 70.0 [IQR 66.0, 74.4] years;178 female;NC/SCD/MCI 127/162/86). All subjects underwent a rich neuropsychological assessment. We focused on baseline memory and executive function-derived from multiple neuropsychological tests using confirmatory factor analysis-, baseline preclinical Alzheimer's cognitive composite 5 (PACC5) scores, and changes in PACC5 scores over the course of three years (Delta PACC5).ResultsSubjects with hypertension or A beta positivity presented the largest WMH volumes (p(FDR) < 0.05), with spatial overlap in the frontal (hypertension: 0.42 +/- 0.17;A beta: 0.46 +/- 0.18), occipital (hypertension: 0.50 +/- 0.16;A beta: 0.50 +/- 0.16), parietal lobes (hypertension: 0.57 +/- 0.18;A beta: 0.56 +/- 0.20), corona radiata (hypertension: 0.45 +/- 0.17;A beta: 0.40 +/- 0.13), optic radiation (hypertension: 0.39 +/- 0.18;A beta: 0.74 +/- 0.19), and splenium of the corpus callosum (hypertension: 0.36 +/- 0.12;A beta: 0.28 +/- 0.12). Elevated global and regional WMH volumes coincided with worse cognitive performance at baseline and over 3 years (p(FDR) < 0.05). A beta positivity was negatively associated with cognitive performance (direct effect-memory: - 0.33 +/- 0.08, p(FDR) < 0.001;executive: - 0.21 +/- 0.08, p(FDR) < 0.001;PACC5: - 0.29 +/- 0.09, p(FDR) = 0.006;Delta PACC5: - 0.34 +/- 0.04, p(FDR) < 0.05). Splenial WMH mediated the relationship between hypertension and cognitive performance (indirect-only effect-memory: - 0.05 +/- 0.02, p(FDR) = 0.029;executive: - 0.04 +/- 0.02, p(FDR) = 0.067;PACC5: - 0.05 +/- 0.02, p(FDR) = 0.030;Delta PACC5: - 0.09 +/- 0.03, p(FDR) = 0.043) and WMH in the optic radiation partially mediated that between A beta positivity and memory (indirect effect-memory: - 0.05 +/- 0.02, p(FDR) = 0.029).ConclusionsPosterior white matter is susceptible to hypertension and A beta accumulation. Posterior WMH mediate the association between these pathologies and cognitive dysfunction, making them a promising target to tackle the downstream damage related to the potentially interacting and potentiating effects of the two pathologies
Competition and moral behavior: A meta-analysis of forty-five crowd-sourced experimental designs
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