872 research outputs found

    Cloud Classification with Unsupervised Deep Learning

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    We present a framework for cloud characterization that leverages modern unsupervised deep learning technologies. While previous neural network-based cloud classification models have used supervised learning methods, unsupervised learning allows us to avoid restricting the model to artificial categories based on historical cloud classification schemes and enables the discovery of novel, more detailed classifications. Our framework learns cloud features directly from radiance data produced by NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) satellite instrument, deriving cloud characteristics from millions of images without relying on pre-defined cloud types during the training process. We present preliminary results showing that our method extracts physically relevant information from radiance data and produces meaningful cloud classes.Comment: 5 pages, 6 figures, Proceedings for Climate Informatics Workshop 2019 Pari

    Energiewende beschleunigen? EngpĂ€sse berĂŒcksichtigen!

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    Als Reaktion auf die Preisentwicklungen auf dem europĂ€ischen Gasmarkt und die AbhĂ€ngigkeit von russischen Erdgasimporten wird mittlerweile vermehrt eine Beschleunigung der Energiewende gefordert. WĂ€hrend eine Mehrheit der Bevölkerung dies vermutlich spĂ€testens seit der Invasion der Ukraine unterstĂŒtzen dĂŒrfte, sollte nicht ĂŒbersehen werden, dass es dadurch zumindest kurzfristig zu diversen EngpĂ€ssen bei ArbeitskrĂ€ften, Vorleistungen und InvestitionsgĂŒtern kommen könnte: Grund dafĂŒr ist, dass der entsprechende NachfrageĂŒberhang zu steigenden Kosten fĂŒhren wĂŒrde. Dadurch wiederum könnte die Energiewende wieder gebremst werden. Dieser Policy Brief legt zunĂ€chst die Rolle von Erdgas im energetischen Endverbrauch in Österreich dar und diskutiert danach, welche Herausforderungen sich im Falle einer Beschleunigung der Energiewende in Bezug auf zwei Substitute fĂŒr Erdgas stellen werden, die im politischen Diskurs hĂ€ufig genannt werden, wenn es darum geht, einen wesentlichen Teil der elektrischen und thermischen Verwendung von Erdgas zu ersetzen. Dies sind erneuerbare Gase, mit einer zukĂŒnftig wichtigen Rolle auf dem Strommarkt, sowie Alternativen zu Erdgas bei der WĂ€rmewende der Haushalte. WĂ€hrend die Substitution mit erneuerbaren Energien bei der Stromerzeugung zur Spitzenlastabdeckung nur mittelfristig möglich ist, gibt es bei der Einsparung und Substitution von Erdgas im WĂ€rmebereich auch ein erhebliches kurzfristiges Potenzial. Entscheidend ist der limitierende Faktor, der möglicherweise auch nicht unmittelbar substituiert werden kann. Sollte es tatsĂ€chlich zu einer Beschleunigung der Energiewende kommen, so sollten EngpĂ€sse durch ein geeignetes Monitoring antizipiert werden, um mögliche Gegenmaßnahmen ergreifen zu können

    Co-ordination of brain and heart oscillations during non-rapid eye movement sleep

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    Oscillatory activities of the brain and heart show a strong variation across wakefulness and sleep. Separate lines of research indicate that non‐rapid eye movement (NREM) sleep is characterised by electroencephalographic slow oscillations (SO), sleep spindles, and phase–amplitude coupling of these oscillations (SO–spindle coupling), as well as an increase in high‐frequency heart rate variability (HF‐HRV), reflecting enhanced parasympathetic activity. The present study aimed to investigate further the potential coordination between brain and heart oscillations during NREM sleep. Data were derived from one sleep laboratory night with polysomnographic monitoring in 45 healthy participants (22 male, 23 female; mean age 37 years). The associations between the strength (modulation index [MI]) and phase direction of SO–spindle coupling (circular measure) and HF‐HRV during NREM sleep were investigated using linear modelling. First, a significant SO–spindle coupling (MI) was observed for all participants during NREM sleep, with spindle peaks preferentially occurring during the SO upstate (phase direction). Second, linear model analyses of NREM sleep showed a significant relationship between the MI and HF‐HRV (F = 20.1, r (2) = 0.30, p < 0.001) and a tentative circular‐linear correlation between phase direction and HF‐HRV (F = 3.07, r (2) = 0.12, p = 0.056). We demonstrated a co‐ordination between SO–spindle phase–amplitude coupling and HF‐HRV during NREM sleep, presumably related to parallel central nervous and peripheral vegetative arousal systems regulation. Further investigating the fine‐graded co‐ordination of brain and heart oscillations might improve our understanding of the links between sleep and cardiovascular health

    Acoustic stimulation during sleep predicts long-lasting increases in memory performance and beneficial amyloid response in older adults.

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    BACKGROUND Sleep and neurodegeneration are assumed to be locked in a bi-directional vicious cycle. Improving sleep could break this cycle and help to prevent neurodegeneration. We tested multi-night phase-locked acoustic stimulation (PLAS) during slow wave sleep (SWS) as a non-invasive method to improve SWS, memory performance and plasma amyloid levels. METHODS 32 healthy older adults (agemean: 68.9) completed a between-subject sham-controlled three-night intervention, preceded by a sham-PLAS baseline night. RESULTS PLAS induced increases in sleep-associated spectral-power bands as well as a 24% increase in slow wave-coupled spindles, known to support memory consolidation. There was no significant group-difference in memory performance or amyloid-beta between the intervention and control group. However, the magnitude of PLAS-induced physiological responses were associated with memory performance up to 3 months post intervention and beneficial changes in plasma amyloid. Results were exclusive to the intervention group. DISCUSSION Multi-night PLAS is associated with long-lasting benefits in memory and metabolite clearance in older adults, rendering PLAS a promising tool to build upon and develop long-term protocols for the prevention of cognitive decline

    Help-seeking attitudes and behaviours for mental health problems in adolescents before and during the first COVID-19 school closures in Germany.

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    AIM Comparing measures of psychological wellbeing and help-seeking in youths before and within the first school closures due to the coronavirus disease 2019 (COVID-19) pandemic enables a better understanding of the effects the pandemic has for those seeking professional help for mental health problems. METHODS Data were obtained from the Germany-based ProHEAD school study. Pre-lockdown and lockdown samples (n = 648) were compared regarding pupils' psychological wellbeing, help-seeking attitudes and help-seeking behaviour. RESULTS Participants from the lockdown sample showed greater positive attitudes towards seeking professional help, whereas psychological wellbeing and help-seeking behaviour remained stable. CONCLUSIONS Possible explanations may include an increased public discourse on mental health or self-selection bias for participation during lockdown

    Quality of Care in Contraceptive Services Provided to Young People in Two Ugandan Districts: A Simulated Client Study

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    BACKGROUND: Low and inconsistent use of contraceptives by young people contributes to unintended pregnancies. This study assessed quality of contraceptive services for young people aged 15-24 in two rural districts in Uganda. METHODS: Five female and two male simulated clients (SCs) interacted with 128 providers at public, private not-for-profit (PNFP), and private for profit (PFP) health facilities. After consultations, SCs were interviewed using a structured questionnaire. Six aspects of quality of care (client's needs, choice of contraceptive methods, information given to users, client-provider interpersonal relations, constellation of services, and continuity mechanisms) were assessed. Descriptive statistics and factor analysis were performed. RESULTS: Means and categorized quality scores for all aspects of quality were low in both public and private facilities. The lowest quality scores were observed in PFP, and medium scores in PNFP facilities. The choice of contraceptive methods and interpersonal relations quality scores were slightly higher in public facilities. Needs assessment scores were highest in PNFP facilities. All facilities were classified as having low scores for appropriate constellation of services. Information given to users was suboptimal and providers promoted specific contraceptive methods. Minority of providers offered preferred method of choice and showed respect for privacy. CONCLUSIONS: The quality of contraceptive services provided to young people was low. Concurrent quality improvements and strengthening of health systems are needed

    Scaling up of highly active antiretroviral therapy in a rural district of Malawi: an effectiveness assessment.

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    BACKGROUND: The recording of outcomes from large-scale, simplified HAART (highly active antiretroviral therapy) programmes in sub-Saharan Africa is critical. We aimed to assess the effectiveness of such a programme held by MĂ©decins Sans FrontiĂšres (MSF) in the Chiradzulu district, Malawi. METHODS: We scaled up and simplified HAART in this programme since August, 2002. We analysed survival indicators, CD4 count evolution, virological response, and adherence to treatment. We included adults who all started HAART 6 months or more before the analysis. HIV-1 RNA plasma viral load and self-reported adherence were assessed on a subsample of patients, and antiretroviral resistance mutations were analysed in plasma with viral loads greater than 1000 copies per mL. Analysis was by intention to treat. FINDINGS: Of the 1308 patients who were eligible, 827 (64%) were female, the median age was 34.9 years (IQR 29.9-41.0), and 1023 (78%) received d4T/3TC/NVP (stavudine, lamivudine, and nevirapine) as a fixed-dose combination. At baseline, 1266 individuals (97%) were HAART-naive, 357 (27%) were at WHO stage IV, 311 (33%) had a body-mass index of less than 18.5 kg/m2, and 208 (21%) had a CD4 count lower than 50 cells per muL. At follow-up (median 8.3 months, IQR 5.5-13.1), 967 (74%) were still on HAART, 243 (19%) had died, 91 (7%) were lost to follow-up, and seven (0.5%) discontinued treatment. Low body-mass index, WHO stage IV, male sex, and baseline CD4 count lower than 50 cells per muL were independent determinants of death in the first 6 months. At 12 months, the probability of individuals still in care was 0.76 (95% CI 0.73-0.78) and the median CD4 gain was 165 (IQR 67-259) cells per muL. In the cross-sectional survey (n=398), 334 (84%) had a viral load of less than 400 copies per mL. Of several indicators measuring adherence, self-reported poor adherence (<80%) in the past 4 days was the best predictor of detectable viral load (odds ratio 5.4, 95% CI 1.9-15.6). INTERPRETATION: These data show that large numbers of people can rapidly benefit from antiretroviral therapy in rural resource-poor settings and strongly supports the implementation of such large-scale simplified programmes in Africa

    Translating HbA1c measurements into estimated average glucose values in pregnant women with diabetes

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    Aims/hypothesis This study aimed to examine the relationship between average glucose levels, assessed by continuous glucose monitoring (CGM), and HbA1c levels in pregnant women with diabetes to determine whether calculations of standard estimated average glucose (eAG) levels from HbA1c measurements are applicable to pregnant women with diabetes. Methods CGM data from 117 pregnant women (89 women with type 1 diabetes; 28 women with type 2 diabetes) were analysed. Average glucose levels were calculated from 5–7 day CGM profiles (mean 1275 glucose values per profile) and paired with a corresponding (±1 week) HbA1c measure. In total, 688 average glucose–HbA1c pairs were obtained across pregnancy (mean six pairs per participant). Average glucose level was used as the dependent variable in a regression model. Covariates were gestational week, study centre and HbA1c. Results There was a strong association between HbA1c and average glucose values in pregnancy (coefficient 0.67 [95% CI 0.57, 0.78]), i.e. a 1% (11 mmol/mol) difference in HbA1c corresponded to a 0.67 mmol/l difference in average glucose. The random effects model that included gestational week as a curvilinear (quadratic) covariate fitted best, allowing calculation of a pregnancy-specific eAG (PeAG). This showed that an HbA1c of 8.0% (64 mmol/mol) gave a PeAG of 7.4–7.7 mmol/l (depending on gestational week), compared with a standard eAG of 10.2 mmol/l. The PeAG associated with maintaining an HbA1c level of 6.0% (42 mmol/mol) during pregnancy was between 6.4 and 6.7 mmol/l, depending on gestational week. Conclusions/interpretation The HbA1c–average glucose relationship is altered by pregnancy. Routinely generated standard eAG values do not account for this difference between pregnant and non-pregnant individuals and, thus, should not be used during pregnancy. Instead, the PeAG values deduced in the current study are recommended for antenatal clinical care

    Computational Study of the Human Dystrophin Repeats: Interaction Properties and Molecular Dynamics

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    Dystrophin is a large protein involved in the rare genetic disease Duchenne muscular dystrophy (DMD). It functions as a mechanical linker between the cytoskeleton and the sarcolemma, and is able to resist shear stresses during muscle activity. In all, 75% of the dystrophin molecule consists of a large central rod domain made up of 24 repeat units that share high structural homology with spectrin-like repeats. However, in the absence of any high-resolution structure of these repeats, the molecular basis of dystrophin central domain's functions has not yet been deciphered. In this context, we have performed a computational study of the whole dystrophin central rod domain based on the rational homology modeling of successive and overlapping tandem repeats and the analysis of their surface properties. Each tandem repeat has very specific surface properties that make it unique. However, the repeats share enough electrostatic-surface similarities to be grouped into four separate clusters. Molecular dynamics simulations of four representative tandem repeats reveal specific flexibility or bending properties depending on the repeat sequence. We thus suggest that the dystrophin central rod domain is constituted of seven biologically relevant sub-domains. Our results provide evidence for the role of the dystrophin central rod domain as a scaffold platform with a wide range of surface features and biophysical properties allowing it to interact with its various known partners such as proteins and membrane lipids. This new integrative view is strongly supported by the previous experimental works that investigated the isolated domains and the observed heterogeneity of the severity of dystrophin related pathologies, especially Becker muscular dystrophy

    Gender Differences and the Impact of Partnership and Children on Quality of Life During the COVID-19 Pandemic

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    Objectives: The COVID-19 pandemic and its protective measures have changed the daily lives of families and may have affected quality of life (QoL). The aim of this study was to analyze gender differences in QoL and to examine individuals living in different partnership and family constellations.Methods: Data from the Gutenberg COVID-19 cohort study (N = 10,250) with two measurement time points during the pandemic (2020 and 2021) were used. QoL was assessed using the EUROHIS-QOL questionnaire. Descriptive analyses and autoregressive regressions were performed.Results: Women reported lower QoL than men, and QoL was significantly lower at the second measurement time point in both men and women. Older age, male gender, no migration background, and higher socioeconomic status, as well as partnership and children (especially in men), were protective factors for QoL. Women living with children under 14 and single mothers reported significantly lower QoL.Conclusion: Partnership and family were protective factors for QoL. However, women with young children and single mothers are vulnerable groups for lower QoL. Support is especially needed for women with young children
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