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Ensuring Grasp Safety in Upper-Limb Prostheses:a Predictive Risk Approach
No full textThis work aims to enhance shared-autonomy control methods in myoelectric hand prostheses. We present a method to predict object slipping using a machine learning algorithm, that combines friction cone theory and bandpass filtering to detect and classify slips according to the context, particularly as “safe” and “risky” slips. Preliminary experimental validation with a multi-articulated prosthesis equipped with six Hall-effect tactile sensors showed the method effectiveness in discriminating among the two slips categories. Despite this approach faced some challenges, results showed the potential to avoid autonomous reactions where there is no potential risk involved, such as social interactions (i.e. passing an object) or voluntary object releasing
Forecasting rainfall events based on zenith wet delay time series utilizing eXtreme Gradient Boosting (XGBoost)
No full textAccurate rainfall prediction is vital for mitigating flood and storm disasters as well as for planning agricultural activities and water resources management. GNSS observations enable the estimation of atmospheric water vapor content through the Zenith Wet Delay (ZWD) value, where previous studies indicate a strong correlation between the ZWD-derived indicators and rainfall events. However, specifying these indicators is challenging due to the spatial variability of precipitation and the location of GNSS stations. While many studies have integrated meteorological parameters with GNSS-derived Zenith Total Delay (ZTD) values to enhance prediction accuracy, the scarcity of meteorological instruments at GNSS stations remains a limitation. In this study, we employed ZWD-derived features and utilized the eXtreme Gradient Boosting (XGBoost) classification method to predict rainfall events. Ten parameters (including station latitude, longitude, elevation, ZWD monthly anomaly, ZWD slope, ZWD maximum, maximum ZWD derivative, month, hour, and precipitation flag) were used as features in the input layer of the considered XGBoost model. For training, data from 40 GNSS stations spanning five consecutive years (2016 to 2020) in the eastern United States of America were analyzed to derive the required features from 4-hour ZWD time series. To evaluate the proposed method, estimated rainfall was compared with the observations of weather stations during 2021. Furthermore, the results of five GNSS stations (not included in the training) were compared with the regional rainfall events of 2016 to 2021. Our results indicate that the proposed method achieves a mean True Forecast Rate (TFR) and a mean False Forecast Rate (FFR) of approximately 0.75 and 0.15, respectively, demonstrating performance comparable to studies incorporating meteorological parameters
Ledelse af pædagogisk forandring:En empirisk analyse af syv skolers arbejde med at integrere problem-baseret pædagogik i undervisningen
No full textDenne artikel undersøger, hvilke ledelsesmæssige kompetencer der er nødvendige for at implementere problem- og projektbaseret læring (PBL) i den danske folkeskole. Med udgangspunkt i et skoleudviklingsprojekt i Rebild Kommune, hvor syv skoler arbejder med at integrere PBL i alle fag og klassetrin, analyseres ledernes erfaringer og praksis. Artiklen bygger på empirisk materiale i form af kvalitative interviews med skoleledere og anvender en tematisk analyse til at identificere fem centrale ledelseshandlinger: 1) Talk the talk – walk the walk, 2) Spot PBL-talenterne, 3) Dyrk medarbejdernes PBL-mindset, 4) Hold øjnene på bolden og 5) Hav tillid til processen. Disse handlinger relateres til fire dominerende ledelsesteorier: instructional-, transformational- og distributed leadership samt capacity building. Artiklen argumenterer for, at pædagogisk ledelse ikke kan adskilles fra den pædagogik, der praktiseres, og at skoleledelse må forstås som en situeret og kontekstafhængig praksis. Der peges på, at ledelse af pædagogisk forandring kræver en balanceret tilgang mellem styring og frisættelse, hvor lederen både sætter retning og understøtter medarbejdernes professionelle dømmekraft. Artiklen bidrager med ny viden om, hvordan skoleledere kan agere som brobyggere mellem politiske visioner og lokal pædagogisk praksis i arbejdet med at integrere problembaseret læring i folkeskolen
Associations between central and brachial blood pressure in patients with hypertension and aortovascular disease: Implications for clinical practice.
Get PDFCentral blood pressure (CBP) measurements, compared to brachial blood pressure (bBP), offer a superior predictive accuracy for aortovascular disease outcomes. This emphasises the distinctiveness of central hemodynamic metrics such as CBP, measuring the pressure directly exerted from the cardiac muscle to the major arteries, and provides a more direct assessment of cardiovascular workload than bBP, which measures the pressure against peripheral artery walls. This review synthesises findings evaluating the correlation between CBP and key aortovascular disease markers. Thoracic aortic aneurysm (TAA) growth is a crucial aspect of aortovascular assessment. CBP more accurately correlates with arterial stiffness (AS), the growth of TAA, and cardiovascular diseases, offering a more dependable prediction of aortovascular diseases, adverse cardiovascular events (CVE) and organ damage compared to bBP. The incorporation of CBP into routine clinical practice could enhance aortovascular assessments and therapeutic strategies when compared to bBP, particularly through a deeper understanding of aortic wave dynamics, which could fundamentally alter aortovascular diagnostics and treatment. In conclusion, integrating CBP into aortovascular and cardiovascular risk management is encouraged. Further research is necessary to substantiate these aspects and explore the operative implications of CBP in clinical settings
What Can We Learn about the Effects of Democracy Using Cross-National Data?
Get PDFMore than 1,100 studies have been published that examine the effects of democracy using cross-national data since 2000. This article examines whether these analyses have sufficient statistical power to detect an effect of democracy. Using Monte Carlo simulation and examining consensus effects previously reported in the literature, the article finds that studies are only powered to detect very strong effects of democracy when examining countries over time. This raises questions about what sort of relationships can be analyzed using cross-national data.</p
Large Language Models are Easily Confused:A Quantitative Metric, Security Implications and Typological Analysis
Get PDFLanguage Confusion is a phenomenon where Large Language Models (LLMs) generate text that is neither in the desired language, nor in a contextually appropriate language. This phenomenon presents a critical challenge in text generation by LLMs, often appearing as erratic and unpredictable behavior. We hypothesize that there are linguistic regularities to this inherent vulnerability in LLMs and shed light on patterns of language confusion across LLMs. We introduce a novel metric, Language Confusion Entropy, designed to directly measure and quantify this confusion, based on language distributions informed by linguistic typology and lexical variation. Comprehensive comparisons with the Language Confusion Benchmark (Marchisio et al., 2024) confirm the effectiveness of our metric, revealing patterns of language confusion across LLMs. We further link language confusion to LLM security, and find patterns in the case of multilingual embedding inversion attacks. Our analysis demonstrates that linguistic typology offers theoretically grounded interpretation, and valuable insights into leveraging language similarities as a prior for LLM alignment and security
Human Molecular Mechanisms of Discogenic Low Back Pain:A Scoping Review
Get PDFThe limited understanding of the mechanisms underlying human discogenic low back pain (DLBP) has hampered the development of effective treatments. While there is much research on disc degeneration, the association between degeneration and pain is weak. Therefore, there is an urgent need to identify pain-inducing molecular mechanism to facilitate the development of mechanism-specific therapeutics. This scoping review aims to determine the current knowledge of molecular mechanisms associated with human DLBP. A systematic search on CENTRAL, CINAHL, Citation searching, ClinicalTrials.gov, Embase, Google Scholar, MEDLINE, PsycINFO, PubMed, Scopus, Web of Science, and World Health Organization was performed. Studies with human DLBP as diagnosed by discography or imaging that analyzed human disc tissues and reported pain-related outcomes were included, and those on predominant radicular pain were excluded. The search returned 6012 studies. Most studies did not collect pain-related outcomes. Those that included pain assessment relied on self-report of pain intensity and disability. Six studies qualified for data extraction and synthesis. The main molecular mechanisms associated with DLBP were the expressions of nociceptive neuropeptides and cytokines, particularly TNF-αdue to its strong association with pain outcomes. Activation of NF-κB signaling pathway, alterations in adrenoceptor expressions, and increase in reactive oxygen species (ROS) were also associated with DLBP through regulation of pro-inflammatory factors and pain-related neuropeptides. Current evidence converges to TNF-α, NF-κB signaling, and ROS-induced pro-inflammation. Major weaknesses in the current literature are the focus on degeneration without pain phenotyping, and lack of association of molecular findings with pain outcomes. PERSPECTIVE: This scoping review identified TNF-α, NF-κB signaling, and ROS-induced pro-inflammation as relevant mechanisms of human discogenic low back pain. Major weaknesses in the current literature are the focus on degeneration without pain phenotyping, and lack of association of molecular findings with pain outcomes.</p
The effect of stretching intensity on pain sensitivity: A randomized crossover study on healthy adults
Get PDFBackgroundStretching exercises have effects on local and widespread pain sensitivity. A dose–response relationship may exist between the analgesic effect and the intensity of stretching, such that a higher intensity of stretching may generate a larger reduction in analgesic response, but this remains to be studied. This study aimed to examine the dose–response relationship between stretching intensity and the analgesic effect.MethodsA randomized, repeated-measures crossover study was performed to examine the effect of stretching to the first point of pain onset and stretching to the point of a sensation of stretching (discomfort). The primary outcome was regional and distant pressure pain thresholds.ResultsThirty-one participants (n = 24 female) were available for analysis. We observed a 22.2% increase in regional pressure pain thresholds (93.2 kPa, p = 0.001) and a 15.0% increase in distant pressure pain thresholds (50.9 kPa, p = 0.012) following stretching to the point of stretch. We observed a 20.0% increase in regional pressure pain thresholds (90.3 kPa, p = 0.001) and a 15.1% increase in distant pressure pain thresholds (52.1 kPa, p = 0.004) following stretching to the point of pain.ConclusionsThe results showed that local and widespread pain sensitivity decreased following acute stretching, regardless of stretching intensity. No differences in pain sensitivity were found between stretching to the point of stretch or stretching to the first onset of pain. Thus, the results showed no evidence of a dose–response relationship between stretching intensity and the analgesic effect.SignificanceThe study showed a significant acute hypoalgesic effect of stretching exercises regardless of stretching intensity. This may have appropriate clinical implications for patients with musculoskeletal and nociplastic pain
