994 results on '"Zörner A"'
Search Results
2. Reliability of patient-specific gait profiles with inertial measurement units during the 2-min walk test in incomplete spinal cord injury
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Willi, Romina, Werner, Charlotte, Demkó, László, de Bie, Rob, Filli, Linard, Zörner, Björn, Curt, Armin, and Bolliger, Marc
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- 2024
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3. Reliability of patient-specific gait profiles with inertial measurement units during the 2-min walk test in incomplete spinal cord injury
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Romina Willi, Charlotte Werner, László Demkó, Rob de Bie, Linard Filli, Björn Zörner, Armin Curt, and Marc Bolliger
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Medicine ,Science - Abstract
Abstract Most established clinical walking tests assess specific aspects of movement function (velocity, endurance, etc.) but are generally unable to determine specific biomechanical or neurological deficits that limit an individual’s ability to walk. Recently, inertial measurement units (IMU) have been used to collect objective kinematic data for gait analysis and could be a valuable extension for clinical assessments (e.g., functional walking measures). This study assesses the reliability of an IMU-based overground gait analysis during the 2-min walk test (2mWT) in individuals with spinal cord injury (SCI). Furthermore, the study elaborates on the capability of IMUs to distinguish between different gait characteristics in individuals with SCI. Twenty-six individuals (aged 22–79) with acute or chronic SCI (AIS: C and D) completed the 2mWT with IMUs attached above each ankle on 2 test days, separated by 1 to 7 days. The IMU-based gait analysis showed good to excellent test–retest reliability (ICC: 0.77–0.99) for all gait parameters. Gait profiles remained stable between two measurements. Sensor-based gait profiling was able to reveal patient-specific gait impairments even in individuals with the same walking performance in the 2mWT. IMUs are a valuable add-on to clinical gait assessments and deliver reliable information on detailed gait pathologies in individuals with SCI. Trial registration: NCT04555759.
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- 2024
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4. Evidence for reticulospinal plasticity underlying motor recovery in Brown-Séquard-plus Syndrome: a case report
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Antonia Maria Eilfort, Maria Rasenack, Björn Zörner, Armin Curt, and Linard Filli
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Brown-Séquard Syndrome ,spinal cord injury ,reticulospinal tract ,corticospinal tract ,StartReact ,motor recovery ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Brown-Séquard Syndrome (BSS) is a rare neurological condition caused by a unilateral spinal cord injury (SCI). Upon initial ipsilesional hemiplegia, patients with BSS typically show substantial functional recovery over time. Preclinical studies on experimental BSS demonstrated that spontaneous neuroplasticity in descending motor systems is a key mechanism promoting functional recovery. The reticulospinal (RS) system is one of the main descending motor systems showing a remarkably high ability for neuroplastic adaptations after incomplete SCI. In humans, little is known about the contribution of RS plasticity to functional restoration after SCI. Here, we investigated RS motor drive to different muscles in a subject with Brown-Séquard-plus Syndrome (BSPS) five months post-injury using the StartReact paradigm. RS drive was compared between ipsi- and contralesional muscles, and associated with measures of functional recovery. Additionally, corticospinal (CS) drive was investigated using transcranial magnetic stimulation (TMS) in a subset of muscles. The biceps brachii showed a substantial enhancement of RS drive on the ipsi- vs. contralesional side, whereas no signs of CS plasticity were found ipsilesionally. This finding implies that motor recovery of ipsilesional elbow flexion is primarily driven by the RS system. Results were inversed for the ipsilesional tibialis anterior, where RS drive was not augmented, but motor-evoked potentials recovered over six months post-injury, suggesting that CS plasticity contributed to improvements in ankle dorsiflexion. Our findings indicate that the role of RS and CS plasticity in motor recovery differs between muscles, with CS plasticity being essential for the restoration of distal extremity motor function, and RS plasticity being important for the functional recovery of proximal flexor muscles after SCI in humans.
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- 2024
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5. Cracking the code: mapping residential building energy performance in rural Central Asia through building typologies
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Kedar Mehta and Wilfried Zörner
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Energy demand modelling ,Energy use in building ,Central Asia ,Cold-climate ,EnergyPlus ,Building simulation ,Science ,Technology - Abstract
Abstract Buildings in rural Central Asia have unique characteristics as they were built during the Soviet era (during 1950–1960) without any energy efficiency measures. The special and aged building stock pose a crucial challenge on energy security and energy supply. However, accurate scientific data on their energy usage is lacking, highlighting a research gap about robust and validated methodology to determine the energy use of rural Central Asian buildings. In response to this need, this research paper proposes a set of generalised residential building typologies for rural Central Asia, with a focus on Kyrgyzstan. The study combines quantitative and qualitative methods, including household surveys, energy demand modelling, EnergyPlus simulations, and result validation. It derives energy-based building typologies from construction year and building envelope characteristics. Through numerous validated simulations, it was identified that the heat demand for rural Kyrgyz houses is 3–5 times here compared to European houses (250–400 kWh/m2). The study revealed the estimated heat demand for homes in rural Kyrgyzstan, indicating a significant potential for improving building energy efficiency in the region. These results can inform specific approaches, such as building renovation plans, energy certification, and renovation strategies. Furthermore, the validated methodology introduced offers opportunities for researchers in the field of building energy efficiency and can be applied to similar regions in Central Asia with comparable building stocks and climates.
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- 2023
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6. Agri-PV (Agrivoltaics) in Developing Countries: Advancing Sustainable Farming to Address the Water–Energy–Food Nexus
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Kedar Mehta, Meeth Jeetendra Shah, and Wilfried Zörner
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Agri-PV ,agrivoltaics ,Uzbekistan ,water–energy–food nexus ,Agri-PV in developing countries ,Central Asia ,Technology - Abstract
The escalating demand for water, energy, and food, coupled with the imperative for sustainable development, necessitates innovative solutions to address the complex interdependencies within the water–energy–food nexus. In this context, agriculture and photovoltaics (Agri-PV or Agri–voltaics) systems have emerged as a promising approach to promoting sustainable agricultural practices while enhancing energy efficiency and food production. However, limited research, especially on the technical aspects of Agri-PV, has resulted in a knowledge gap regarding how to model and determine the suitability of Agri-PV for different crops based on local conditions. This study presents a novel approach to modeling and simulating Agri-PV systems for various major crops in developing countries, using Uzbekistan as a case study. It provides a blueprint for selecting suitable Agri-PV systems. The research investigates the technical feasibility of Agri-PV technology tailored to Uzbekistan’s agricultural landscape, with broader implications for Central Asia. Employing a systematic methodology, the study begins by selecting appropriate sites and crops for Agri-PV system testing, ensuring the relevance and applicability of the research findings to the local context. Using advanced software tools such as PVSyst, the study accurately calculates photosynthetically active radiation (PAR) values specific to selected crops, bridging a significant knowledge gap and providing empirical data essential for informed decision making. The methodology further incorporates an in-depth analysis of economic and technical considerations in selecting PV modules and inverters, enhancing the scientific accuracy of the study. By strategically modeling Agri-PV systems based on parameters like row density, module distance, and tilt angle, this research aims to optimize the integration of photovoltaic technology with agricultural practices in Uzbekistan. Moreover, this study helps to understand the impact of Agri-PV systems on the water–energy–food nexus, providing valuable insights into the potential benefits and challenges specific to the region. The study identifies the positive impact of Agri-PV on major crops and provides a suitable design and modeling approach for sustainable farming practices.
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- 2024
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7. Cracking the code: mapping residential building energy performance in rural Central Asia through building typologies
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Mehta, Kedar and Zörner, Wilfried
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- 2023
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8. Study protocol: short against long antibiotic therapy for infected orthopedic sites — the randomized-controlled SALATIO trials
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Uçkay, Ilker, Wirth, Stephan, Zörner, Björn, Fucentese, Sandro, Wieser, Karl, Schweizer, Andreas, Müller, Daniel, Zingg, Patrick, and Farshad, Mazda
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- 2023
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9. Lower Recurrence Rates of Atrial Fibrillation and MACE Events After Early Compared to Late Ablation: A Danish Nationwide Register Study
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Jacob Tønnesen, Martin H. Ruwald, Jannik Pallisgaard, Peter Vibe Rasmussen, Arne Johannessen, Jim Hansen, Rene H. Worck, Christopher R. Zörner, Lise Riis‐Vestergaard, Charlotte Middelfart, Samuel K. Sørensen, Stefan Sattler, Gunnar Gislason, and Morten Lock Hansen
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ablation ,atrial fibrillation ,diagnosis‐to‐ablation time ,recurrence of atrial fibrillation ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Guidelines recommend prioritizing treatment with antiarrhythmic drugs before referral of patients with atrial fibrillation to ablation, delaying a potential subsequent ablation. However, delaying ablation may affect ablation outcomes. We sought to investigate the impact of duration from diagnosis to ablation on the risk of atrial fibrillation recurrence and adverse events. Methods and Results Using Danish nationwide registries, all patients with first‐time ablation for atrial fibrillation were identified and included from 2010 to 2018. Patients were divided into 4 groups by diagnosis‐to‐ablation time: 2.9 years (late ablation). The primary end point was atrial fibrillation recurrence after the 90‐day blanking period, defined by admission for atrial fibrillation, cardioversions, use of antiarrhythmic drugs, or repeat atrial fibrillation ablations. The secondary end point was a composite end point of heart failure, ischemic stroke, or death, and each event individually. The study cohort consisted of 7705 patients. The 5‐year cumulative incidence of atrial fibrillation recurrence in the 4 groups was 42.9%, 54.8%, 55.9%, and 58.4%, respectively. Hazard ratios were 1.20 (95% CI, 1.07–1.35), 1.29 (95% CI, 1.13–1.47), and 1.40 (95% CI, 1.28–1.53), respectively, with the early ablation group as reference. The hazard ratio for the combined secondary end point was 1.22 (95% CI, 1.04–1.44) in the late ablation group compared with the early ablation group. Conclusions In patients undergoing ablation for atrial fibrillation, early ablation was associated with a significantly lower risk of atrial fibrillation recurrence. Furthermore, the associated risk of heart failure, ischemic stroke, or death was significantly lower in early‐compared with late‐ablation patients.
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- 2024
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10. Comfort in cold: A novel approach to sustainable building energy efficiency
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Mehta, Kedar and Zörner, Wilfried
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- 2024
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11. Statistical analysis of solar thermal collectors in the Solar Keymark Database
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Summ, Thorsten, Oyinlola, Muyiwa, Khattak, Sanober, Trinkl, Christoph, and Zörner, Wilfried
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- 2024
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12. Comfort in cold: A novel approach to sustainable building energy efficiency
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Kedar Mehta and Wilfried Zörner
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High-altitude ,Cold climate ,Building energy ,Building renovation ,Local insulation materials ,Sustainable building energy efficiency ,Renewable energy sources ,TJ807-830 - Abstract
Kyrgyzstan's high-altitude rural housing sector consumes 3–5 times more energy than European buildings due to ageing infrastructure, lack of insulation, and reliance on non-sustainable resources. One potential solution is the implementation of thermal insulation. However, due to limited public awareness of energy efficiency, inadequate government policies, insufficient technology, and challenging geography, people in rural areas rely on non-sustainable resources such as coal, cow dung, and firewood for heating, which creates a negative impact on the local ecosystems. To close the energy efficiency gap, the paper proposes a sustainable and holistic approach that integrates thermal insulation with effective energy efficiency planning using a staged-renovation approach by utilising locally available insulation materials / resources. The feasibility study presented in the paper was conducted with a simulation-based parametric study to recognise the potential of novel and sustainable insulation structures on building heat demand. This innovative approach can potentially reduce heat demand in high-altitude houses by as much as 70 %, offering a transformative solution. Furthermore, its adaptability makes it transferable to similar high-altitude communities, thus advancing sustainable energy practices for climate change mitigation and contributing to broader sustainable development goals.
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- 2024
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13. Verbindung von Fach- und Sprachlernen als Zugang zu Forschendem Lernen
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Thomas Must and Anika Zörner
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Aufgabenstellung ,Deutsch als Zweitsprache ,Fachlernen ,Forschendes Lernen ,Operator ,Sprachlernen ,Education (General) ,L7-991 - Abstract
Der Beitrag, der die Ergebnisse einer Kooperation von Geschichtsdidaktik und Deutsch als Zweitsprache im Rahmen des Projektes BiProfessional zusammenführt, zeigt Herausforderungen in der Verbindung von Fach- und Sprachlernen hinsichtlich der Konzeption von Aufgabenstellungen auf. Im Mittelpunkt steht dabei das von Zörner und Must weiterentwickelte Konkretisierungsraster (2019, zurückgehend auf Tajmel & Hägi-Mead, 2017), das die Strukturierung einer Aufgabengestaltung unterstützen und Gelegenheit zu Reflexionen über die Mehrdeutigkeit von Operatoren bieten soll. Insbesondere Letzteres soll Impulse für Forschendes Lernen schaffen und sowohl Studierende als auch tätige Lehrkräfte für die Erfordernisse einer sprachsensiblen Aufgabengestaltung sensibilisieren. Hierfür liefert der Beitrag konkrete didaktische Anregungen und Materialien für den Einsatz in Seminar- und Fortbildungskontexten.
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- 2023
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14. Study protocol: short against long antibiotic therapy for infected orthopedic sites — the randomized-controlled SALATIO trials
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Ilker Uçkay, Stephan Wirth, Björn Zörner, Sandro Fucentese, Karl Wieser, Andreas Schweizer, Daniel Müller, Patrick Zingg, and Mazda Farshad
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Orthopedic infections ,Osteomyelitis ,Surgical debridement ,Antibiotic duration ,Remission ,Adverse events ,Medicine (General) ,R5-920 - Abstract
Abstract Background Few studies address the appropriate duration of post-surgical antibiotic therapy for orthopedic infections; with or without infected residual implants. We perform two similar randomized-clinical trials (RCT) to reduce the antibiotic use and associated adverse events. Methods Two unblinded RCTs in adult patients (non-inferiority with a margin of 10%, a power of 80%) with the primary outcomes “remission” and “microbiologically-identical recurrences” after a combined surgical and antibiotic therapy. The main secondary outcome is antibiotic-related adverse events. The RCTs allocate the participants between 3 vs. 6 weeks of post-surgical systemic antibiotic therapy for implant-free infections and between 6 vs. 12 weeks for residual implant-related infections. We need a total of 280 episodes (randomization schemes 1:1) with a minimal follow-up of 12 months. We perform two interim analyses starting approximately after 1 and 2 years. The study approximatively lasts 3 years. Discussion Both parallel RCTs will enable to prescribe less antibiotics for future orthopedic infections in adult patients. Trial registration ClinicalTrial.gov NCT05499481. Registered on 12 August 2022. Protocol version: 2 (19 May 2022)
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- 2023
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15. Need of energy transition at roof of the world: Correlative approach to interpret energy identity of high-altitude Central Asian communities
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Mehta, Kedar, Ehrenwirth, Mathias, Zörner, Wilfried, and Greenough, Richard
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- 2023
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16. The money-inflation nexus revisited
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Ringwald, Leopold and Zörner, Thomas O.
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- 2023
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17. Validity and reliability of the 2-minute walk test in individuals with spinal cord injury
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Willi, Romina, Widmer, Mario, Merz, Nora, Bastiaenen, Caroline H. G., Zörner, Björn, and Bolliger, Marc
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- 2023
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18. PV-Optimized Heat Pump Control in Multi-Family Buildings Using a Reinforcement Learning Approach
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Michael Bachseitz, Muhammad Sheryar, David Schmitt, Thorsten Summ, Christoph Trinkl, and Wilfried Zörner
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reinforcement learning ,PV-optimization ,heat pump ,multi-family building ,energy-management system ,Technology - Abstract
For the energy transition in the residential sector, heat pumps are a core technology for decarbonizing thermal energy production for space heating and domestic hot water. Electricity generation from on-site photovoltaic (PV) systems can also contribute to a carbon-neutral building stock. However, both will increase the stress on the electricity grid. This can be reduced by using appropriate control strategies to match electricity consumption and production. In recent years, artificial intelligence-based approaches such as reinforcement learning (RL) have become increasingly popular for energy-system management. However, the literature shows a lack of investigation of RL-based controllers for multi-family building energy systems, including an air source heat pump, thermal storage, and a PV system, although this is a common system configuration. Therefore, in this study, a model of such an energy system and RL-based controllers were developed and simulated with physical models and compared with conventional rule-based approaches. Four RL algorithms were investigated for two objectives, and finally, the soft actor–critic algorithm was selected for the annual simulations. The first objective, to maintain only the required temperatures in the thermal storage, could be achieved by the developed RL agent. However, the second objective, to additionally improve the PV self-consumption, was better achieved by the rule-based controller. Therefore, further research on the reward function, hyperparameters, and advanced methods, including long short-term memory layers, as well as a training for longer time periods than six days are suggested.
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- 2024
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19. Temporal trends of hypertrophic cardiomyopathy in Denmark: a nationwide retrospective cohort study
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Anne-Marie Schjerning, Jannik Pallisgaard, Gunnar Gislason, Peter Vibe Rasmussen, Morten Lock Hansen, Jacob Tønnesen, Christopher Ryan Zörner, Morten Kvistholm Jensen, Lise Da Riis-Vestergaard, and Charlotte Middelfart
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Medicine - Abstract
Objectives To describe the population of patients diagnosed with hypertrophic cardiomyopathy (HCM) in Denmark and determine temporal trends in incidence and patient characteristics over time.Design Nationwide retrospective cohort study.Setting Danish nationwide administrative and clinical registers and databases.Participants All patients aged ≥16 years diagnosed with HCM from 2005 to 2018.Outcomes measures Time trends in HCM diagnosis, patient characteristics, comorbidities and pharmacotherapy were identified and tested for significance using the Cochran-Armitage trend test.Results 3856 HCM patients were included (median age 68 years (IQR 56–78)). Although there were more males (53%), females were older (72 years vs 63 years) and more likely to have their type of HCM classified as obstructive (54% vs 38%). A consistent rise in HCM cases per year was detected and there was a significant decline in prevalence of heart failure (2005: 20% to 2018: 12%, p
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- 2023
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20. Effect of argon concentration on thermal efficiency of gas-filled insulating glass flat-plate collectors
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Summ, Thorsten, Ehrenwirth, Mathias, Trinkl, Christoph, Zörner, Wilfried, Pischow, Kaj, Greenough, Richard, and Oyinlola, Muyiwa
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- 2023
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21. Mapping Potential for Improving Rural Energy Services in Kyrgyzstan: Factors for Achieving Sustainable Development Goals in the Community Context
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Kedar Mehta, Mathias Ehrenwirth, Christoph Trinkl, and Wilfried Zörner
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energy need ,rural livelihood ,energy poverty ,energy services ,sustainable energy transition ,sustainable development goals ,Social Sciences - Abstract
Energy is a pivotal element for overall development. Therefore, affordable and clean energy for all (Sustainable Development Goal 7) is one of the important elements. Despite a suitable approach, Kyrgyzstan lags behind to achieve its Sustainable Development Goals by 2030. Improving access to energy can significantly impact the progress of many other sustainable development targets. However, access to reliable, sustainable, and adequate energy is a crucial task in rural Kyrgyzstan. Taking into consideration the energy situation and the importance of the availability of energy services, the overarching aim of the presented article is to map the potential of improving rural energy services to foster overall sustainable development goals. The article presents the most relevant information about rural energy usage behaviour based on three primary pillars: energy demand, energy carrier, and energy sources. In addition, the presented research article synthesises the key driving factors which have a direct or indirect impact on the energy services in rural areas. The summarised data displays a deep insight into a variety of complex and dynamic household energy consumption patterns. The article provides a potential solution nexus to foster improved energy services in rural Kyrgyzstan and therefore to foster the overall sustainable development in Kyrgyzstan. The findings of the article help to formulate a strategy to design rural energy services for policy makers and stockholders.
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- 2022
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22. Evidence for reticulospinal plasticity underlying motor recovery in Brown-Séquard-plus Syndrome: a case report
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Eilfort, Antonia Maria, primary, Rasenack, Maria, additional, Zörner, Björn, additional, Curt, Armin, additional, and Filli, Linard, additional
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- 2024
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23. Optimization Model of Hybrid Renewable Energy Generation for Electric Bus Charging Stations
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Ahmed Bazzi, Hamza El Hafdaoui, Ahmed Khallaayoun, Kedar Mehta, Kamar Ouazzani, and Wilfried Zörner
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electric buses ,HOMER ,on-site renewable energy generation ,sustainable transport ,hybrid renewable energy generation ,grid-connected renewable energy system ,Technology - Abstract
This paper introduces a comprehensive approach for sizing grid-connected hybrid renewable energy systems tailored for electric bus fleet operations. The study involves two main steps. First, a mathematical model that optimizes the configuration of such systems by considering daily electric bus consumption, solar irradiance, wind speed, and biomass potential is formulated. The model utilizes Pareto frontier multi-objective optimization to minimize the net present cost, the cost of energy, and greenhouse gas emissions. Second, the model is rigorously applied and tested in a real-world case study in Fez, Morocco, using HOMER Pro; the case study centers on the daily energy requirements of the buses, estimated at 2.5 megawatt hours per day, with a peak demand of 345 kilowatts. Two scenarios are explored, revealing a discernible trade-off dilemma between the full hybrid renewable energy scenario (Scenario 1) and the grid-connected hybrid renewable energy scenario (Scenario 2). In Scenario 2, the grid-connected hybrid renewable energy system demonstrates a notable 42.8% reduction in the net present cost, totaling USD 984,624. Similarly, the levelized cost of energy experiences a significant decrease, reaching approximately 0.08 USD/kWh, marking a 38.1% reduction. However, this apparent economic advantage is juxtaposed with a critical consideration—an increase in greenhouse gas emissions from null to 330,418 kg/year.
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- 2023
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24. Stochastic model specification in Markov switching vector error correction models
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Hauzenberger, Niko, Huber, Florian, Pfarrhofer, Michael, and Zörner, Thomas O.
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Economics - Econometrics - Abstract
This paper proposes a hierarchical modeling approach to perform stochastic model specification in Markov switching vector error correction models. We assume that a common distribution gives rise to the regime-specific regression coefficients. The mean as well as the variances of this distribution are treated as fully stochastic and suitable shrinkage priors are used. These shrinkage priors enable to assess which coefficients differ across regimes in a flexible manner. In the case of similar coefficients, our model pushes the respective regions of the parameter space towards the common distribution. This allows for selecting a parsimonious model while still maintaining sufficient flexibility to control for sudden shifts in the parameters, if necessary. We apply our modeling approach to real-time Euro area data and assume transition probabilities between expansionary and recessionary regimes to be driven by the cointegration errors. The results suggest that the regime allocation is governed by a subset of short-run adjustment coefficients and regime-specific variance-covariance matrices. These findings are complemented by an out-of-sample forecast exercise, illustrating the advantages of the model for predicting Euro area inflation in real time., Comment: Keywords: Nonlinear vector error correction model, hierarchical modeling, inflation forecasting, Euro area; JEL: C11, C32, E31, E32, E44
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- 2018
25. Predicting crypto-currencies using sparse non-Gaussian state space models
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Hotz-Behofsits, Christian, Huber, Florian, and Zörner, Thomas O.
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Economics - Econometrics ,Quantitative Finance - Statistical Finance - Abstract
In this paper we forecast daily returns of crypto-currencies using a wide variety of different econometric models. To capture salient features commonly observed in financial time series like rapid changes in the conditional variance, non-normality of the measurement errors and sharply increasing trends, we develop a time-varying parameter VAR with t-distributed measurement errors and stochastic volatility. To control for overparameterization, we rely on the Bayesian literature on shrinkage priors that enables us to shrink coefficients associated with irrelevant predictors and/or perform model specification in a flexible manner. Using around one year of daily data we perform a real-time forecasting exercise and investigate whether any of the proposed models is able to outperform the naive random walk benchmark. To assess the economic relevance of the forecasting gains produced by the proposed models we moreover run a simple trading exercise.
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- 2018
26. Towards Sustainable Community Development through Renewable Energies in Kyrgyzstan: A Detailed Assessment and Outlook
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Kedar Mehta, Mathias Ehrenwirth, Christoph Trinkl, and Wilfried Zörner
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Central Asia ,energy services ,high-altitude ,Kyrgyzstan ,renewable energy resources ,sustainable energy ,Social Sciences - Abstract
In rural Kyrgyzstan, the energy need is usually derived from multiple natural energy resources such as firewood, charcoal, agricultural residues, animal dung, and wood branches, which are considered common and predominant practices. Because of the non-sustainable resources and heavy reliance on the environment, Kyrgyzstan is one of the most vulnerable countries to climate change in Central Asia. On the contrary, the great renewable energy potential in Kyrgyzstan is untapped, which could be the most promising solution to ensuring sustainable energy supply in the country. However, because of the lack of scientific knowledge, current energy policies, and the lack of infrastructure, renewable resources are mainly untapped. To exploit the country’s renewable energy potential, there is a need for a systematic diagnosis to develop a strategy to explore renewables in Kyrgyzstan, which is currently missing in the existing literature. In that regard, the presented study aims to assess the current status of renewable energy sources by considering the local energy context from a potential point of view. Further to this, it provides a comparative overview through a matrix of strengths, weaknesses, opportunities, and threats. Such novel analysis would be the fundamental base for formulating policy advice and a national plan to enhance the utilization of renewable energy in Kyrgyzstan. The presented analysis was carried out based on the extensive literature review, the country’s national plan, and the existing energy policies of Kyrgyzstan. The article found out that there is huge potential available for the renewable energy market. As compared to other renewable energy sources, solar energy has great potential and can be considered one of the pioneer sustainable sources for integration into the country’s power generation framework.
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- 2022
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27. Comprehensive analysis of the energy legislative framework of Kyrgyzstan: Investigation to develop a roadmap of Kyrgyz renewable energy sector
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Mehta, Kedar, Mingaleva, Ekaterina, Zörner, Wilfried, Degembaeva, Nadira, and Baibagyshov, Ermek
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- 2022
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28. Meta-Profile and Competencies for Harmonisation of Higher Education in Sector-Specific Technology Areas: A Case Study of Renewable Energy in Southern Africa
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Zörner, Wilfri, Mahomed, Nawaz, Zulu, Ackim, Bader, Tobias, Tenthani, Chifundo, Cuamba, Boaventura, and Chingosho, Hilton
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The aim of this study was to develop the profile and competencies of a harmonised curriculum for a multi-country regional sector-specific higher education programme. The study, which was based on a case study of Renewable Energy involving six countries in Southern Africa, was based on established methodologies proposed by previous studies on harmonisation and profiling of higher education programmes. The study uses a general curriculum development approach leading to the definition of generic and specific competencies and feeding into a learning taxonomy to create alignment with specific learning outcomes at the intended qualification level. However, the approach extends the harmonisation concept to include industrialisation potential, which is crucial in the developing-country context. This allows for the exploitation of shared resources in sector-specific technology areas and supports the development of regional standards on technology and practice, as part of developing a sustainable regional economic sector. Twenty-two competencies, encompassing both generic and specific competencies, were defined. These competencies were grouped into six key competence areas, and later transformed into four clusters of competencies: core competencies, hard skills, soft skills and attitudes. These four clusters were then placed on a planetary system to represent the meta-profile for the qualification, which forms the framework for the future design of learning materials for the qualification.
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- 2020
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29. The Impact of Credit Market Sentiment Shocks.
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BOECK, MAXIMILIAN and ZÖRNER, THOMAS O.
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BOND market ,MARKET sentiment ,BUSINESS cycles ,MACROECONOMIC models ,ECONOMIC shock - Abstract
This paper investigates the role of credit market sentiment and investor beliefs in credit cycle dynamics and their transmission to businesscycle fluctuations. Using U.S. data from 1968 to 2014, we find that credit market sentiment is indeed able to detect asymmetries in a small‐scale macroeconomic model. An unexpected credit market sentiment shock has different impacts in an optimistic and pessimistic credit market environment. While an unexpected movement in the optimistic regime leads to a rather muted impact on output and credit, we find a significant negative impact on these variables in the pessimistic regime. The findings highlight the relevance of expectation formation mechanisms as a source of macroeconomic instability. [ABSTRACT FROM AUTHOR]
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- 2024
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30. Injecting climate finance into SME lending in Germany: Opportunities for and limitations of regional savings and cooperative banks.
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Flögel, Franz, Schepelmann, Philipp, Zademach, Hans-Martin, and Zörner, Michael
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COOPERATIVE banking industry ,LOANS ,REGIONAL banks ,ENVIRONMENTAL, social, & governance factors ,SAVINGS banks - Abstract
Although small and medium-sized enterprises (SMEs) contribute considerably to Germany's carbon emissions, regional savings and cooperative banks − SMEs' most important financiers − hardly consider this aspect in lending to these businesses. However, given Germany's commitment to climate neutrality by 2045, suitable approaches for injecting climate finance into these SME lending processes are greatly required. Against this background, the paper at hand aims to introduce the specific case of regional banks into the debate on green finance and green banking and suggest future research in this context. In discussing the state of research on the peculiarities of regional savings and cooperative banks, we outline the resulting opportunities and limitations for climate impact assessments in SME lending. We argue that while the dual bottom-line orientation of regional banks in Germany precludes them from applying simple positive or negative screenings, their in-depth knowledge about local clients and circumstances enables them to be active and engaging partners for the green transformation of SMEs. Nonetheless, we explain why developing solutions to utilise this knowledge for climate finance by integrating climate impact assessments into routine lending processes remains a particularly challenging task. [ABSTRACT FROM AUTHOR]
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- 2024
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31. Disparities in the access to atrial fibrillation ablation in Denmark: who gets ablated, who neglected?
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Zörner, Christopher R, Tønnesen, Jacob, Riis-Vestergaard, Lise Da, Middelfart, Charlotte, Hein, Regitze, Rasmussen, Peter Vibe, Ruwald, Martin H, Gislason, Gunnar, and Hansen, Morten Lock
- Abstract
Aims Atrial fibrillation (AF) is a common arrhythmia associated with reduced quality of life that can lead to serious complications such as stroke and heart failure. Ablation is a safe and effective treatment for AF but is not offered equally to all patients. The aim of this study is to identify demographic groups more or less likely to undergo AF ablation. Methods and results All patients with newly diagnosed AF between 2010 and 2018 were identified in the Danish nationwide registries. The association between gender, age, level of education and attachment to the job market, and the likelihood of receiving AF ablation was investigated using multivariable Cox proportional hazard analysis. Cumulative incidence was calculated using the Aalen–Johansen estimator. A total of 176 248 patients were included. Men were more likely to receive ablation than women (7% vs. 3%). Patients aged 25–44 and 45–64 were most likely to receive ablation, while only 0.7% of patients aged 80 or above received ablation. The rate of ablation significantly decreased with decreasing level of education. Full-time employed patients were most likely to receive ablation, followed by self-employed, unemployed, on sick leave, undergoing education, and early retired patients. Retired patients were the least likely to receive ablation (3%). Conclusion This study found that women, older patients, patients with lower levels of education, and patients on social benefits are less likely to receive AF ablation. These findings suggest that there are significant social and economic disparities in AF ablation treatment in Denmark. [ABSTRACT FROM AUTHOR]
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- 2024
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32. Agri-PV (Agrivoltaics) in Developing Countries: Advancing Sustainable Farming to Address the Water–Energy–Food Nexus.
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Mehta, Kedar, Shah, Meeth Jeetendra, and Zörner, Wilfried
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PHOTOSYNTHETICALLY active radiation (PAR) ,SUSTAINABILITY ,SUSTAINABLE agriculture ,SOFTWARE development tools ,AGRICULTURE - Abstract
The escalating demand for water, energy, and food, coupled with the imperative for sustainable development, necessitates innovative solutions to address the complex interdependencies within the water–energy–food nexus. In this context, agriculture and photovoltaics (Agri-PV or Agri–voltaics) systems have emerged as a promising approach to promoting sustainable agricultural practices while enhancing energy efficiency and food production. However, limited research, especially on the technical aspects of Agri-PV, has resulted in a knowledge gap regarding how to model and determine the suitability of Agri-PV for different crops based on local conditions. This study presents a novel approach to modeling and simulating Agri-PV systems for various major crops in developing countries, using Uzbekistan as a case study. It provides a blueprint for selecting suitable Agri-PV systems. The research investigates the technical feasibility of Agri-PV technology tailored to Uzbekistan's agricultural landscape, with broader implications for Central Asia. Employing a systematic methodology, the study begins by selecting appropriate sites and crops for Agri-PV system testing, ensuring the relevance and applicability of the research findings to the local context. Using advanced software tools such as PVSyst, the study accurately calculates photosynthetically active radiation (PAR) values specific to selected crops, bridging a significant knowledge gap and providing empirical data essential for informed decision making. The methodology further incorporates an in-depth analysis of economic and technical considerations in selecting PV modules and inverters, enhancing the scientific accuracy of the study. By strategically modeling Agri-PV systems based on parameters like row density, module distance, and tilt angle, this research aims to optimize the integration of photovoltaic technology with agricultural practices in Uzbekistan. Moreover, this study helps to understand the impact of Agri-PV systems on the water–energy–food nexus, providing valuable insights into the potential benefits and challenges specific to the region. The study identifies the positive impact of Agri-PV on major crops and provides a suitable design and modeling approach for sustainable farming practices. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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33. General anaesthesia compared to conscious sedation for first-time atrial fibrillation catheter ablation—a Danish nationwide cohort study.
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Riis-Vestergaard, Lise Da, Tønnesen, Jacob, Ruwald, Martin H, Zörner, Christopher R, Middelfart, Charlotte, Hein, Regitze, Johannessen, Arne, Hansen, Jim, Worck, Rene Husted, Gislason, Gunnar, and Hansen, Morten Lock
- Abstract
Aims Catheter ablation (CA) is a well-established treatment option for atrial fibrillation (AF), where sedation and analgesia are pivotal for patient comfort and lesion formation. The impact of anaesthesia type on AF recurrence rates remains uncertain. This study aimed to examine AF recurrence rates depending on conscious sedation (CS) vs. general anaesthesia (GA) during CA. Methods and results Utilizing nationwide data from the Danish healthcare registries, we conducted this cohort study involving adults (≥18 years) undergoing first-time CA for AF between 2010 and 2018. Patients were categorized by anaesthesia type (CS or GA), with the primary endpoint being AF recurrence, defined by a composite endpoint of either antiarrhythmic drug (AAD) prescriptions, AF-related hospital admissions, electrical cardioversions, or AF re-ablation. The impact of anaesthesia type was evaluated using multivariable Cox proportional hazards analysis. The study cohort comprised 7957 (6421 CS and 1536 GA) patients. Persistent AF, hypertension, and heart failure, as well as use of AAD, were more prevalent in the GA group. Cumulative incidences of recurrent AF were higher in the CS group at 1 (46% vs. 37%) and at 5 (68% vs. 63%) years. Multivariate analysis revealed CS as significantly associated with increased risk of AF recurrence at 5-year follow-up [hazard ratio 1.26 (95% confidence interval 1.15–1.38)], consistent across paroxysmal and persistent AF subtypes. Conclusion This nationwide cohort study suggests a higher risk of AF recurrence with CS during CA compared to GA. These results advocate for considering GA as the preferred anaesthesia type for improved CA outcomes. [ABSTRACT FROM AUTHOR]
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- 2024
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34. Blockchain-based Local Energy Grids: Advanced Use Cases and Architectural Considerations.
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Marco Peise, Jörn Kuhlenkamp, Anselm Busse, Jacob Eberhardt, Max-Robert Ulbricht, Stefan Tai, Jörg Baus, Martin Kassebaum, and Thorsten Zörner
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- 2021
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35. PV-Optimized Heat Pump Control in Multi-Family Buildings Using a Reinforcement Learning Approach
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Bachseitz, Michael, primary, Sheryar, Muhammad, additional, Schmitt, David, additional, Summ, Thorsten, additional, Trinkl, Christoph, additional, and Zörner, Wilfried, additional
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- 2024
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36. Lower Recurrence Rates of Atrial Fibrillation and MACE Events After Early Compared to Late Ablation: A Danish Nationwide Register Study
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Tønnesen, Jacob, primary, Ruwald, Martin H., additional, Pallisgaard, Jannik, additional, Rasmussen, Peter Vibe, additional, Johannessen, Arne, additional, Hansen, Jim, additional, Worck, Rene H., additional, Zörner, Christopher R., additional, Riis‐Vestergaard, Lise, additional, Middelfart, Charlotte, additional, Sørensen, Samuel K., additional, Sattler, Stefan, additional, Gislason, Gunnar, additional, and Hansen, Morten Lock, additional
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- 2024
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37. Exploring Human-Robot Trust Through the Investment Game: An Immersive Space Mission Scenario.
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Emy Arts, Sebastian Zörner, Kavish Bhatia, Glareh Mir, Florian Schmalzl, Ankit Srivastava, Brenda Vasiljevic, Tayfun Alpay, Annika Peters, Erik Strahl, and Stefan Wermter
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- 2020
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38. NILM based Energy Disaggregation Algorithm for Dairy Farms.
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Akhilesh Yadav, Anuj Sinha, Abdessamad Saidi 0003, Christoph Trinkl, and Wilfried Zörner
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- 2020
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39. Large Differences in Livelihood Responses and Outcomes to Increased Conservation Enforcement in a Protected Area
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Persson, Joel, Ford, Scott, Keophoxay, Anousith, Mertz, Ole, Nielsen, Jonas Østergaard, Vongvisouk, Thoumthone, and Zörner, Michael
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- 2021
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40. How to Enhance Energy Services in Informal Settlements? Qualitative Comparison of Renewable Energy Solutions
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Rebekka Besner, Kedar Mehta, and Wilfried Zörner
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informal settlements ,energy access ,Sub-Saharan Africa ,Energy-Hub ,Mini-Grid ,Technology - Abstract
More than half of the urban population of Sub-Saharan Africa lives in informal housing conditions. While urban areas are, in general, characterized by a high electrification rate, residents of informal settlements are still affected by energy poverty, the use of traditional energy sources and unreliable electricity supply. The aim of the study is to give an overview of different renewable-energy-based solutions which are able to improve local energy provision. These are Solar Home Systems, Mini-Grids, and Energy-Hubs. The technologies are compared to another option for improving energy supply, namely Grid Expansion. The analysis is based on 24 Key Performance Indicators, which can be classified into technical, economic, environmental, social, and political dimensions. The selection of indicators is based on the challenges prevalent in informal settlements that impede a comprehensive, sustainable energy supply. The literature-based indices are used to determine which of the four technologies is a suitable solution for minimizing the challenges prevailing in informal settlements. The resulting matrix provides a holistic comparison and serves as a decision aid in selecting the appropriate technology for future projects in informal settlements, depending on local conditions and the needs of the population. The results show that the Energy-Hub is a valid alternative for energy supply improvement in Informal Settlements.
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- 2023
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41. Credit cycles, human capital and the distribution of income
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Kubin, Ingrid and Zörner, Thomas O.
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- 2021
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42. Reliability of patient-specific gait profiles with inertial measurement units during the 2-min walk test in incomplete spinal cord injury
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Willi, Romina; https://orcid.org/0000-0003-3453-4476, Werner, Charlotte; https://orcid.org/0000-0003-3070-6445, Demkó, László; https://orcid.org/0000-0001-5677-2331, de Bie, Rob, Filli, Linard; https://orcid.org/0000-0003-3882-2504, Zörner, Björn; https://orcid.org/0000-0003-2246-3359, Curt, Armin, Bolliger, Marc; https://orcid.org/0000-0001-9059-0304, Willi, Romina; https://orcid.org/0000-0003-3453-4476, Werner, Charlotte; https://orcid.org/0000-0003-3070-6445, Demkó, László; https://orcid.org/0000-0001-5677-2331, de Bie, Rob, Filli, Linard; https://orcid.org/0000-0003-3882-2504, Zörner, Björn; https://orcid.org/0000-0003-2246-3359, Curt, Armin, and Bolliger, Marc; https://orcid.org/0000-0001-9059-0304
- Abstract
Most established clinical walking tests assess specific aspects of movement function (velocity, endurance, etc.) but are generally unable to determine specific biomechanical or neurological deficits that limit an individual's ability to walk. Recently, inertial measurement units (IMU) have been used to collect objective kinematic data for gait analysis and could be a valuable extension for clinical assessments (e.g., functional walking measures). This study assesses the reliability of an IMU-based overground gait analysis during the 2-min walk test (2mWT) in individuals with spinal cord injury (SCI). Furthermore, the study elaborates on the capability of IMUs to distinguish between different gait characteristics in individuals with SCI. Twenty-six individuals (aged 22-79) with acute or chronic SCI (AIS: C and D) completed the 2mWT with IMUs attached above each ankle on 2 test days, separated by 1 to 7 days. The IMU-based gait analysis showed good to excellent test-retest reliability (ICC: 0.77-0.99) for all gait parameters. Gait profiles remained stable between two measurements. Sensor-based gait profiling was able to reveal patient-specific gait impairments even in individuals with the same walking performance in the 2mWT. IMUs are a valuable add-on to clinical gait assessments and deliver reliable information on detailed gait pathologies in individuals with SCI.
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- 2024
43. Lower Recurrence Rates of Atrial Fibrillation and MACE Events After Early Compared to Late Ablation:A Danish Nationwide Register Study
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Tønnesen, Jacob, Ruwald, Martin H., Pallisgaard, Jannik, Rasmussen, Peter Vibe, Johannessen, Arne, Hansen, Jim, Worck, Rene H., Zörner, Christopher R., Riis-Vestergaard, Lise, Middelfart, Charlotte, Sørensen, Samuel K., Sattler, Stefan, Gislason, Gunnar, Hansen, Morten Lock, Tønnesen, Jacob, Ruwald, Martin H., Pallisgaard, Jannik, Rasmussen, Peter Vibe, Johannessen, Arne, Hansen, Jim, Worck, Rene H., Zörner, Christopher R., Riis-Vestergaard, Lise, Middelfart, Charlotte, Sørensen, Samuel K., Sattler, Stefan, Gislason, Gunnar, and Hansen, Morten Lock
- Abstract
Background Guidelines recommend prioritizing treatment with antiarrhythmic drugs before referral of patients with atrial fibrillation to ablation, delaying a potential subsequent ablation. However, delaying ablation may affect ablation outcomes. We sought to investigate the impact of duration from diagnosis to ablation on the risk of atrial fibrillation recurrence and adverse events. Methods and Results Using Danish nationwide registries, all patients with first‐time ablation for atrial fibrillation were identified and included from 2010 to 2018. Patients were divided into 4 groups by diagnosis‐to‐ablation time: <1.0 year (early ablation), 1.0 to 1.9 years, 2.0 to 2.9 years, and >2.9 years (late ablation). The primary end point was atrial fibrillation recurrence after the 90‐day blanking period, defined by admission for atrial fibrillation, cardioversions, use of antiarrhythmic drugs, or repeat atrial fibrillation ablations. The secondary end point was a composite end point of heart failure, ischemic stroke, or death, and each event individually. The study cohort consisted of 7705 patients. The 5‐year cumulative incidence of atrial fibrillation recurrence in the 4 groups was 42.9%, 54.8%, 55.9%, and 58.4%, respectively. Hazard ratios were 1.20 (95% CI, 1.07–1.35), 1.29 (95% CI, 1.13–1.47), and 1.40 (95% CI, 1.28–1.53), respectively, with the early ablation group as reference. The hazard ratio for the combined secondary end point was 1.22 (95% CI, 1.04–1.44) in the late ablation group compared with the early ablation group. Conclusions In patients undergoing ablation for atrial fibrillation, early ablation was associated with a significantly lower risk of atrial fibrillation recurrence. Furthermore, the associated risk of heart failure, ischemic stroke, or death was significantly lower in early‐compared with late‐ablation patients., BACKGROUND: Guidelines recommend prioritizing treatment with antiarrhythmic drugs before referral of patients with atrial fibrillation to ablation, delaying a potential subsequent ablation. However, delaying ablation may affect ablation outcomes. We sought to investigate the impact of duration from diagnosis to ablation on the risk of atrial fibrillation recurrence and adverse events. METHODS AND RESULTS: Using Danish nationwide registries, all patients with first-time ablation for atrial fibrillation were identified and included from 2010 to 2018. Patients were divided into 4 groups by diagnosis-to-ablation time: <1.0 year (early ablation), 1.0 to 1.9 years, 2.0 to 2.9 years, and >2.9 years (late ablation). The primary end point was atrial fibrillation recurrence after the 90-day blanking period, defined by admission for atrial fibrillation, cardioversions, use of antiarrhythmic drugs, or repeat atrial fibrillation ablations. The secondary end point was a composite end point of heart failure, ischemic stroke, or death, and each event individually. The study cohort consisted of 7705 patients. The 5-year cumulative incidence of atrial fibrillation recurrence in the 4 groups was 42.9%, 54.8%, 55.9%, and 58.4%, respectively. Hazard ratios were 1.20 (95% CI, 1.07-1.35), 1.29 (95% CI, 1.13-1.47), and 1.40 (95% CI, 1.28-1.53), respectively, with the early ablation group as reference. The hazard ratio for the combined secondary end point was 1.22 (95% CI, 1.04-1.44) in the late ablation group compared with the early ablation group. CONCLUSIONS: In patients undergoing ablation for atrial fibrillation, early ablation was associated with a significantly lower risk of atrial fibrillation recurrence. Furthermore, the associated risk of heart failure, ischemic stroke, or death was significantly lower in early-compared with late-ablation patients.
- Published
- 2024
44. Home Energy Management System Based on Genetic Algorithm for Load Scheduling: A Case Study Based on Real Life Consumption Data
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Reda El Makroum, Ahmed Khallaayoun, Rachid Lghoul, Kedar Mehta, and Wilfried Zörner
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home energy management ,load scheduling ,genetic algorithm ,user comfort ,Technology - Abstract
This paper proposes a home energy management system able to achieve optimized load scheduling for the operation of appliances within a given household. The system, based on the genetic algorithm, provides recommendations for the user to improve the way the energy needs of the home are handled. These recommendations not only take into account the dynamic pricing of electricity, but also the optimization for solar energy usage as well as user comfort. Historical data regarding the times at which the appliances have been used is leveraged through a statistical method to integrate the user’s preference into the algorithm. Based on real life appliance consumption data collected from a household in Morocco, three scenarios are established to assess the performance of the proposed system with each scenario having different parameters. Running the scenarios on the developed MATLAB script shows a cost saving of up to 63.48% as compared to a base scenario for a specific day. These results demonstrate that significant cost saving can be achieved while maintaining user comfort. The addition of supplementary shiftable loads (i.e., an electric vehicle) to the household as well as the limitations of such home energy management systems are discussed. The main contribution of this paper is the real data and including the user comfort as a metric in in the home energy management scheme.
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- 2023
- Full Text
- View/download PDF
45. Understanding the incidence of atrial fibrillation and stroke in hypertrophic cardiomyopathy patients: insights from Danish nationwide registries.
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Zörner, Christopher R, Schjerning, Anne-Marie, Jensen, Morten Kvistholm, Christensen, Alex Hørby, Tfelt-Hansen, Jacob, Tønnesen, Jacob, Riis-Vestergaard, Lise Da, Middelfart, Charlotte, Rasmussen, Peter Vibe, Gislason, Gunnar, and Hansen, Morten Lock
- Abstract
Aims The treatment of atrial fibrillation (AF) in hypertrophic cardiomyopathy (HCM) can be challenging since AF aggravates symptoms and increases the risk of stroke. Which factors contribute to the development of AF and stroke in HCM remains unknown. The aim of this study was to determine the incidence of AF and stroke in HCM patients and identify the risk factors. Methods and results Using Danish national registries, all HCM patients from 2005 to 2018 were included. The association between HCM, incident AF, and stroke was investigated using multivariable Cox proportional hazards analysis. Cumulative incidences were calculated using the Aalen–Johansen estimator. Among the 3367 patients without prevalent AF, 24% reached the endpoint of incident AF with death as a competing risk. Median follow-up time was 4 years. Atrial fibrillation incidence was equal between sexes and increased for patients with ischaemic heart disease [IHD; hazard ratio (HR) 1.33, 95% confidence interval (CI) 1.08–1.63], hypertension (HT) (HR 1.36, 95% CI 1.14–1.67), and obstructive HCM (HR 1.27, 95% CI 1.05–1.52). Seven per cent developed stroke, with no difference detected stratifying for the presence of AF. Sub-analysis revealed that when AF was treated with oral anticoagulants (OACs), stroke was less likely (HR 0.4, 95% CI 0.18–0.86, P = 0.02). However, 34% of patients were not receiving adequate anticoagulation following AF diagnosis. Conclusion Obstructive HCM, HT, and IHD were associated with increased risk of AF. Prevalent AF alone was not predictive of stroke; however, AF patients treated with OAC were significantly less likely to develop stroke, suggesting that this development is driven by the protective effect of OAC. Despite this, 34% of patients did not receive OAC. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
46. Effect of early cryoballoon ablation on atrial fibrillation recurrence—A Danish nationwide register study.
- Author
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Hein, Regitze, Riis‐Vestergaard, Lise Da, Tønnesen, Jacob, Zörner, Christopher Ryan, Rasmussen, Peter Vibe, Ruwald, Martin Huth, Johannessen, Arne, Worck, René Husted, Hansen, Jim, Middelfart, Charlotte, Gislason, Gunnar Hilmar, and Hansen, Morten Lock
- Subjects
RISK assessment ,RESEARCH funding ,CLINICAL trials ,CRYOSURGERY ,TREATMENT effectiveness ,PATIENT care ,LONGITUDINAL method ,ATRIAL fibrillation ,DISEASE relapse ,CONFIDENCE intervals ,TIME ,PROPORTIONAL hazards models ,REGRESSION analysis - Abstract
Introduction: Cryoballoon ablation is a safe and efficient rhythm control strategy in atrial fibrillation (AF) patients. The impact of time from diagnosis to ablation is unclear. The aim of this study was to examine the impact of timing of first‐time cryoballoon ablation on AF recurrence in a nationwide cohort of AF patients. Methods and Results: From nationwide registers, all AF patients ≥18 years of age who underwent first‐time AF cryoballoon ablation in Denmark from 2012 to 2018 were included. The AF patients were stratified by ablation timing: Early group (≤1 year after AF diagnosis), intermediate group (1–3 years after AF diagnosis), and late group (≥3 years after AF diagnosis). By adjusted Cox regression models, the effect of timing on AF recurrence was examined. This study included 1064 AF patients with a median age of 63 years. Most patients were male (66%) and had paroxysmal AF (67%). The 1‐year risk of AF recurrence increased from 31% in the early group to 41% and 44% in the intermediate and late group. The hazard ratios (95% confidence intervals) were 1.28 (0.95, 1.74) in the intermediate group and 1.42 (1.09, 1.86) in the late group when compared to the early group. Continuous diagnosis‐to‐ablation time seemed to have the greatest impact on AF recurrence within the first 2 years. Conclusion: In AF patients undergoing cryoballoon ablation, late timing of ablation was associated with a significantly higher AF recurrence rate when compared to early timing of ablation. These findings support early cryoballoon ablation to improve the outcomes after ablation. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
47. Blockchain-Based Management of Shared Energy Assets Using a Smart Contract Ecosystem
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Utz, Manuel, Albrecht, Simon, Zoerner, Thorsten, Strüker, Jens, van der Aalst, Wil, Series Editor, Mylopoulos, John, Series Editor, Rosemann, Michael, Series Editor, Shaw, Michael J., Series Editor, Szyperski, Clemens, Series Editor, Abramowicz, Witold, editor, and Paschke, Adrian, editor
- Published
- 2019
- Full Text
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48. Generating Value Through Digitalization: Simple and Digital
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Lischka, Andreas, Wolfering-Zoerner, Michaela, Faust, Eva, and Krüssel, Peter, editor
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- 2019
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49. The heterogeneous impact of monetary policy on the US labor market
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Zens, Gregor, Böck, Maximilian, and Zörner, Thomas O.
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- 2020
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50. Fampridine-induced changes in walking kinetics are associated with clinical improvements in patients with multiple sclerosis
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Weller, D., Lörincz, L., Sutter, T., Reuter, K., Linnebank, M., Weller, M., Zörner, B., and Filli, L.
- Published
- 2020
- Full Text
- View/download PDF
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