652 results on '"Angelopoulos, P."'
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2. Nominalization of clauses: The clausal prolepsis strategy
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Angelopoulos, Nikos
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- 2024
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3. Frazil ice changes winter biogeochemical processes in the Lena River
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Opfergelt, Sophie, Gaspard, François, Hirst, Catherine, Monin, Laurence, Juhls, Bennet, Morgenstern, Anne, Angelopoulos, Michael, and Overduin, Pier Paul
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- 2024
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4. Developing and piloting a set of quality-of-care indicators for Romanian public hospitals as part of a national programme to fund quality
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Ivanković, Damir, Fonseca, Válter R., Katsapi, Angeliki, Karaiskou, Angeliki, Angelopoulos, Georgios, Garofil, Dragos, Rogobete, Alexandru, Klazinga, Niek, Azzopardi-Muscat, Natasha, and Breda, João
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- 2024
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5. Effect of aligners on patients’ oral health-related quality of life and anxiety: a prospective pilot study
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Roulias, Panagiotis, Vasoglou, Georgios, Angelopoulos, Gerassimos, Pandis, Nikolaos, and Sifakakis, Iosif
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- 2024
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6. The impact of intersectional racial and gender biases on minority female leadership over two centuries
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Pogrebna, Ganna, Angelopoulos, Spyros, Motsi-Omoijiade, Immaculate, Kharlamov, Alexander, and Tkachenko, Nataliya
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- 2024
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7. Frazil ice changes winter biogeochemical processes in the Lena River
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Sophie Opfergelt, François Gaspard, Catherine Hirst, Laurence Monin, Bennet Juhls, Anne Morgenstern, Michael Angelopoulos, and Pier Paul Overduin
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Geology ,QE1-996.5 ,Environmental sciences ,GE1-350 - Abstract
Abstract The ice-covered period of large Arctic rivers is shortening. To what extent will this affect biogeochemical processing of nutrients? Here we reveal, with silicon isotopes (δ30Si), a key winter pathway for nutrients under river ice. During colder winter phases in the Lena River catchment, conditions are met for frazil ice accumulation, which creates microzones. These are conducive to a lengthened reaction time for biogeochemical processes under ice. The heavier δ30Si values (3.5 ± 0.5 ‰) in river water reflect that 39 ± 11% of the Lena River discharge went through these microzones. Freezing-driven amorphous silica precipitation concomitant to increased ammonium concentration and changes in dissolved organic carbon aromaticity in Lena River water support microbially mediated processing of nutrients in the microzones. Upon warming, suppressing loci for winter intra-river nitrogen processing is likely to modify the balance between N2O production and consumption, a greenhouse gas with a large global warming potential.
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- 2024
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8. Thoracoabdominal approach to large adrenal tumors – when laparoscopic adrenalectomy is not enough: a retrospective four-year study
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Konstantinos Tsalis, Orestis Ioannidis, Natalia Antigoni Savvala, Grigorios Gkasdaris, Panagiotis Christidis, Elissavet Anestiadou, Ioannis Mantzoros, Manousos Pramateftakis, Efstathios Kotidis, Nikolaos Ouzounidis, Vasilis Foutsitzis, Savvas Symeonidis, Stefanos Bitsianis, Angeliki Cheva, and Stamatios Angelopoulos
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Medicine - Abstract
Introduction: Laparoscopic adrenalectomy is considered to be the gold standard approach in the field of adrenal surgery. This technique offers advantages of great importance compared to variant laparotomy techniques. Notwithstanding, a technique that needs to be mentioned is the thoracoabdominal approach which facilitates the anatomic exposure of the retroperitoneum, adrenal gland, and great vessels and is strongly recommended for the surgery of large, malignant adrenal tumors. Aim: The objective of this study is to evaluate the effectiveness and outcomes of the thoracoabdominal approach in adrenal surgery for large adrenal tumors. By presenting our results and experiences, we aim to highlight the advantages of this technique in providing optimal anatomic exposure of the retroperitoneum, adrenal gland, and great vessels, and to establish its role as a viable alternative to laparoscopic adrenalectomy in complex cases. Materials and methods: We reviewed retrospectively the data of our patients admitted to our Surgical Department and treated surgically with the thoracoabdominal incision, performed by a single surgeon at our tertiary care center, over the period 01/01/20-31/12/23. Results: All patients had large retroperitoneal masses of varying complexity, requiring maximal surgical exposure. Seventeen patients in total underwent operation with the indication of unilateral adrenal tumor. Five of those patients underwent a laparoscopic tumor resection, while 12 patients were treated by thoracoabdominal approach. Our study group included 7 women (58%) and 5 men (42%), with average age 57 years. The mean maximum tumor diameter was 10.8 cm. Conclusion: The advantages of the thoracoabdominal approach regarding the exposure of the operative field in challenging cases, together with the low incidence of complications noted in our experience, render this technique an excellent alternative if indicated.
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- 2024
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9. Developing and piloting a set of quality-of-care indicators for Romanian public hospitals as part of a national programme to fund quality
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Damir Ivanković, Válter R. Fonseca, Angeliki Katsapi, Angeliki Karaiskou, Georgios Angelopoulos, Dragos Garofil, Alexandru Rogobete, Niek Klazinga, Natasha Azzopardi-Muscat, and João Breda
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Quality of Health Care ,Quality Improvement ,Quality indicators ,Hospitals ,Romania ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Healthcare systems aim to enhance the health status and well-being of the individuals and populations they serve. To achieve this, measuring and evaluating the quality and safety of services provided and the outcomes achieved is essential. Like other countries, Romania faces challenges regarding the quality of care provided in its public hospitals. To address this, the Romanian Ministry of Health initiated reforms in 2022, including implementing a pay-for-performance model based on quality indicators. This paper presents a descriptive analysis of processes, methods, results and lessons learned from developing and piloting a set of Quality of Care indicators for Romanian public hospitals. Methods World Health Organization’s Athens Office on Quality of Care and Patient Safety assisted Romania in developing and piloting a set of quality-of-care indicators for public hospitals. The development phase included defining indicator domains, identifying potential indicators across these domains, and defining the final indicator set. The piloting phase involved selecting and recruiting piloting hospitals, developing data collection and validation methods and tools, training hospital staff, and collecting and analysing indicator data. Piloting ended with an evaluation workshop. Mixed, quantitative and qualitative methods were used, including literature reviews, stakeholder consultation workshops, survey instruments developed for this study, modified Delphi panels and consensus-building meetings. National stakeholders were actively involved throughout the process. Results Four priority domains were defined for quality-of-care indicators for Romanian public hospitals: patient safety, patient experience, healthcare workforce training and safety, and clinical effectiveness. 25 core indicators were selected across these domains. During the pilot, hospitals achieved an average completion rate of 90% for data submission, with all domains rated equally relevant during post-pilot evaluations. Lessons included the need for supportive legislation, improved internal auditing practices and enhanced staff training, refinement of indicator data collection methods and alignment of indicators with hospital-specific contexts. Conclusions This work presents a significant stride in improving Romanian public hospitals’ quality of care and patient safety. It underscores the importance of high-level commitment, stakeholder engagement, and robust data practices in driving successful quality improvement efforts. Emphasising the role of data-driven and patient-centric approaches in achieving optimal healthcare outcomes, lessons learned offer insights for the continuation of quality improvement work in Romania but also for healthcare systems elsewhere.
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- 2024
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10. Subarctic permafrost formation around seafloor seeps
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Angelopoulos, Michael and Paull, Charles K.
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- 2024
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11. Safety and Efficacy of Percutaneous Morton Neuroma Cryoneurolysis Under Ultrasound Guidance
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Moulin, Benjamin, Angelopoulos, Giorgio, Sarrazin, Jean Luc, Romano, Stephane, Vignaux, Olivier, Guenoun, Thierry, Di Primio, Massimiliano, and Hakime, Antoine
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- 2024
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12. Color Doppler ultrasound and real-time elastography in patients with hypothyroidism for the prediction of levothyroxine replacement: a cross-sectional study of 338 patients
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Angelopoulos, Nikolaos, Goulis, Dimitrios G., Chrisogonidis, Ioannis, Livadas, Sarantis, and Iakovou, Ioannis
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- 2024
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13. Digital product passports as enablers of digital circular economy: a framework based on technological perspective
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Voulgaridis, Konstantinos, Lagkas, Thomas, Angelopoulos, Constantinos Marios, Boulogeorgos, Alexandros-Apostolos A., Argyriou, Vasileios, and Sarigiannidis, Panagiotis
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- 2024
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14. Digital Resilience Through Training Protocols: Learning To Identify Fake News On Social Media
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Soetekouw, Lisa and Angelopoulos, Spyros
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- 2024
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15. Effect of aligners on patients’ oral health-related quality of life and anxiety: a prospective pilot study
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Panagiotis Roulias, Georgios Vasoglou, Gerassimos Angelopoulos, Nikolaos Pandis, and Iosif Sifakakis
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Orthodontic ,Aligner ,Oral health related quality of life ,Anxiety ,Questionnaire ,Psychology ,BF1-990 - Abstract
Abstract Background This prospective study explored the impact of aligners on the oral health-related quality of life and anxiety of patients during the first month of orthodontic treatment and the first month of the retention phase. Methods A total of 23 male and female patients (median age 25 y) treated with clear aligners were included. The OHRQoL questionnaire was used at certain time points during treatment (T1: placement of the first aligner; T2: after one day of use; T3: after seven days; T4: after one month; and T5: after one month in the retention phase). The State-Trait Anxiety Inventory (STAI) was also self-administered to assess state and trait anxiety (Y1 and Y2 subscales, respectively) at the T1, T4 and T5 time points. A population average generalized estimating equations logistic regression model was fit to assess the effect of time on the responses, and the Wald test was used to examine the overall effect of time. Results Overall time was a significant predictor for most of the questions. However, time was marginally significant for the OHRQoL questions evaluating oral symptoms such as bad taste/smell, sores, and food accumulation. Tooth discolouration did not differ between time points. The general activity disturbance was significantly lower in the retention phase. Higher depression and anxiety scores were reported at the initial appointment and decreased thereafter. Conclusions CAT has a negative impact on quality of life and psychological status during the initial days of treatment. These impairments ameliorate at later treatment stages.
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- 2024
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16. Reporting and Grading of Complications in Urological Surgery: Current Trends and Future Perspectives
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Stamatios Katsimperis, Themistoklis Bellos, Ioannis Manolitsis, Ioannis Kyriazis, Panagiotis Angelopoulos, Panagiotis Neophytou, Sotirios Kapsalos, Nikolaos Kostakopoulos, Lazaros Tzelves, Ioannis Varkarakis, Athanasios Papatsoris, Andreas Skolarikos, and Iraklis Mitsogiannis
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Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
There has been a growing need for enhancements in healthcare delivery, especially for the improvement of surgical outcomes. Therefore, implementing consistent reporting of complications enables the evaluation of data quality and facilitates its comparison. There are currently many available reporting and grading systems each with its own set of benefits and drawbacks. In this comprehensive review, we tried to present and assess each of them by demonstrating their criteria and their strong and weak points. To sum up, it seems that there is a need for developing a new reporting and categorization system for complications that are specific to urology.
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- 2024
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17. The Principal Role of Chorus Ducting for Night‐Side Relativistic Electron Precipitation
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Ning Kang, Anton V. Artemyev, Jacob Bortnik, Xiao‐Jia Zhang, and Vassilis Angelopoulos
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Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract Night‐side chorus waves are often observed during plasma sheet injections, typically confined around the equator and thus potentially responsible for precipitation of ≲100 keV electrons. However, recent low‐altitude observations have revealed the critical role of chorus waves in scattering relativistic electrons on the night‐side. This study presents a night‐side relativistic electron precipitation event induced by chorus waves at the strong diffusion regime, as observed by the ELFIN CubeSats. Through event‐based modeling of wave propagation under ducted or unducted regimes, we show that a density duct is essential for guiding chorus waves to high latitudes with minimal damping, thus enabling the strong night‐side relativistic electron precipitation. These findings underline both the existence and the important role of density ducts in facilitating night‐side relativistic electron precipitation.
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- 2024
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18. Solar Energetic Electron Access to the Moon Within the Terrestrial Magnetotail and Shadowing by the Lunar Surface
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Lucas Liuzzo, Andrew R. Poppe, Christina O. Lee, and Vassilis Angelopoulos
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solar energetic electrons ,magnetotail ,Moon ,space weathering ,radiation ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract We present measurements of 30–700 keV Solar Energetic Electrons (SEEs) near the Moon when within the terrestrial magnetotail by the Acceleration, Reconnection, Turbulence, and Electrodynamics of the Moon's Interaction with the Sun spacecraft. Despite their detection deep within the tail, the incident flux and spectral shape of these electrons are nearly identical to measurements taken upstream of Earth in the solar wind by the Wind spacecraft; however, their pitch angle distribution is isotropized compared to the more field‐aligned distribution upstream. We illustrate that SEEs initially traveling Earthward precipitate onto the lunar far‐side, generating extended shadows in the cis‐lunar electron distribution. By modeling the dynamics of these electrons, we show that their precipitation patterns on the lunar near‐side are comparatively reduced. The non‐uniform precipitation and accessibility of potentially hazardous electrons to the Moon's surface are highly relevant in the context of astronaut safety during the planned exploration of the lunar environment.
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- 2024
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19. The Key Role of Magnetic Curvature Scattering in Energetic Electron Precipitation During Substorms
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Ying Zou, Xiao‐Jia Zhang, Anton V. Artemyev, Yangyang Shen, and Vassilis Angelopoulos
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energetic electron precipitation ,substorm ,wave‐particle interaction ,magnetic field curvature scattering ,ionization ,TEC ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract Energetic electron precipitation (EEP) during substorms significantly affects ionospheric chemistry and lower‐ionosphere (
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- 2024
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20. Single-cell analysis reveals lasting immunological consequences of influenza infection and respiratory immunization in the pig lung.
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Andrew Muir, Basudev Paudyal, Selma Schmidt, Ehsan Sedaghat-Rostami, Soumendu Chakravarti, Sonia Villanueva-Hernández, Katy Moffat, Noemi Polo, Nicos Angelopoulos, Anna Schmidt, Matthias Tenbusch, Graham Freimanis, Wilhelm Gerner, Arianne C Richard, and Elma Tchilian
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Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
The pig is a natural host for influenza viruses and integrally involved in virus evolution through interspecies transmissions between humans and swine. Swine have many physiological, anatomical, and immunological similarities to humans, and are an excellent model for human influenza. Here, we employed single cell RNA-sequencing (scRNA-seq) and flow cytometry to characterize the major leukocyte subsets in bronchoalveolar lavage (BAL), twenty-one days after H1N1pdm09 infection or respiratory immunization with an adenoviral vector vaccine expressing hemagglutinin and nucleoprotein with or without IL-1β. Mapping scRNA-seq clusters from BAL onto those previously described in peripheral blood facilitated annotation and highlighted differences between tissue resident and circulating immune cells. ScRNA-seq data and functional assays revealed lasting impacts of immune challenge on BAL populations. First, mucosal administration of IL-1β reduced the number of functionally active Treg cells. Second, influenza infection upregulated IFI6 in BAL cells and decreased their susceptibility to virus replication in vitro. Our data provide a reference map of porcine BAL cells and reveal lasting immunological consequences of influenza infection and respiratory immunization in a highly relevant large animal model for respiratory virus infection.
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- 2024
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21. Inclusion of Nonresonant Effects Into Quasi‐Linear Diffusion Rates for Electron Scattering by Electromagnetic Ion Cyclotron Waves
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Xiaofei Shi, Xin An, Anton Artemyev, Xiao‐Jia Zhang, Didier Mourenas, and Vassilis Angelopoulos
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Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract Electromagnetic ion cyclotron (EMIC) waves are a key plasma mode affecting radiation belt dynamics. These waves are important for relativistic electron losses through scattering and precipitation into Earth's ionosphere. Although theoretical models of such resonant scattering predict a low‐energy cut‐off of ∼1 MeV for precipitating electrons, observations from low‐altitude spacecraft often show simultaneous relativistic and sub‐relativistic electron precipitation associated with EMIC waves. Recently, nonresonant electron scattering by EMIC waves has been proposed as a possible solution to the above discrepancy. We employ this model and a large database of EMIC waves to develop a universal treatment of electron interactions with EMIC waves, including nonresonant effects. We use the Green's function approach to generalize EMIC diffusion rates foregoing the need to modify existing codes or recompute empirical wave databases. Comparison with observations from the electron losses and fields investigation mission demonstrates the efficacy of the proposed method for explaining sub‐relativistic electron losses by EMIC waves.
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- 2024
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22. Secondary Cardiovascular Disease Prevention Deficit Persists over the Years: A Multicenter Cross-Sectional Study Involving 1003 Consecutive Patients from Greece
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Rodis D. Paparodis, Ioannis Androulakis, Dimitrios Askitis, Ilias Perogamvros, Nicholaos Angelopoulos, Andreas Rizoulis, Sarantis Livadas, and Anastasios Boniakos
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LDL-C ,lipids ,ASCVD ,cardiovascular disease ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
Purpose: Lipid lowering treatments (LLTs) can reduce the risk of atherosclerotic cardiovascular disease (ASCVD). Despite the availability of potent LLTs, our clinical observations suggest an inadequate use of such agents. To evaluate this treatment deficit, we designed the present study. Methods: We reviewed the charts of all patients with a history of ASCVD (coronary artery disease—CAD; carotid stenosis—CS; or peripheral artery disease—PAD) diagnosed prior to their first visit to one of our clinics. We recorded their gender, age, ASCVD risk factors (diabetes, hypertension, tobacco use, body mass index), lipid values during that visit and the LLT used. We estimated the rates of the attainment of guideline-specific lipid goals by year, and assessed factors influencing the likelihood of treatment success. Results: Overall, n = 1003 subjects were recruited: CAD n = 703 (70.1%), PAD n = 168 (16.8%), CS n = 325 (32.4%); age 64.7 ± 11.2 years; n = 376 (37.5%) females; n = 642 (64.0%) had diabetes; n = 740 (73.8%) had hypertension; n = 299 (29.8%) were former and n = 367 (36.6%) were current smokers. An appropriate LLT was used in 361 (36.0%) subjects, n = 159 (15.9%) were on no treatment, n = 483 (48.2%) were receiving inadequate therapy, n = 434 (43.3%) were on a high-intensity LLT and n = 361 (36.0%) had achieved the year-specific LDL goals. Success rates ranged from 5.7% to 81.5%, with the lowest being 2020–2023 (5.7–14.5%), p < 0.001. The use of a combination of LLTs and PCSK9 inhibitors led to higher rates of LDL-C goals achievement (p < 0.001). Discussion: Recent secondary ASCVD risk prevention guidelines’ goals are rarely achieved in daily clinical practice, producing a major treatment deficit in this population. Newer systematic interventions are needed to curb this public health issue.
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- 2024
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23. The impact of intersectional racial and gender biases on minority female leadership over two centuries
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Ganna Pogrebna, Spyros Angelopoulos, Immaculate Motsi-Omoijiade, Alexander Kharlamov, and Nataliya Tkachenko
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Medicine ,Science - Abstract
Abstract This study scrutinizes the enduring effects of racial and gender biases that contribute to the consistent underrepresentation of minority women in leadership roles within American private, public, and third sector organizations. We adopt a behavioural data science approach, merging psychological schema theory with sociological intersectionality theory, to evaluate the enduring implications of these biases on female leadership development using mixed methods including machine learning and econometric analysis. Our examination is concentrated on Black female leaders, employing an extensive analysis of leadership rhetoric data spanning 200 years across the aforementioned sectors. We shed light on the continued scarcity of minority female representation in leadership roles, highlighting the role of intersectionality dynamics. Despite Black female leaders frequently embracing higher risks to counter intersectional invisibility compared to their White counterparts, their aspirations are not realized and problems not solved generation after generation, forcing Black female leaders to concentrate on the same issues for dozens and, sometimes, hundreds of years. Our findings suggest that the compound influence of racial and gender biases hinders the advancement of minority female leadership by perpetuating stereotypical behavioral schemas, leading to persistent discriminatory outcomes. We argue for the necessity of organizations to initiate a cultural transformation that fosters positive experiences for future generations of female leaders, recommending a shift in focus from improving outcomes for specific groups to creating an inclusive leadership culture.
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- 2024
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24. Hypercalcemic Crisis Due to a Giant Intrathyroidal Parathyroid Adenoma, with Postsurgical Severe Hypocalcemia and Hungry Bone Syndrome: A Case Report
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Vasileios Papanikos, Elli Papadodima, Dimitra Bantouna, Rodis D. Paparodis, Sarantis Livadas, Nicholaos Angelopoulos, and Evangelos Karvounis
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giant parathyroid adenoma ,hypercalcemic crisis ,hungry bone syndrome ,Medicine (General) ,R5-920 - Abstract
Background: Parathyroid adenoma is the most common cause of hypercalcemia and rarely leads to a hypercalcemic crisis, which is an unusual endocrine emergency that requires timely surgical excision. Case presentation: A 67-year-old male was admitted to the ER of the Euroclinic Hospital, Athens, Greece, because of elevated calcium levels and a palpable right-sided neck mass, which were accompanied by symptoms of nausea, drowsiness, and weakness for six months that increased prior to our evaluation. A gradual creatinine elevation and decreasing mental state were observed as well. The initial laboratory investigation identified severely elevated serum calcium (3.6 mmol/L) levels consistent with a hypercalcemic crisis (HC) and parathyroid hormone PTH (47.6 pmol/L) due to primary hyperparathyroidism. Neck ultrasonography (USG) identified a large, well-shaped cystic mass in the right thyroid lobe. With a serum calcium concentration of 19.5 mg/dL and a PTH of 225.3 pmol/L, the patient underwent partial parathyroidectomy and total thyroidectomy, which decreased serum calcium and PTH to 2.5 mmol/L and 1.93 pmol/L, respectively. Histology revealed a giant intrathyroidal cystic parathyroid adenoma, which was responsible for the hypercalcemic crisis. Postoperatively, the patient developed severe biochemical and clinical hypocalcemia, with calcium concentrations as low as 1.65 mmol/L, consistent with hungry bone syndrome (HBS), which was treated with high doses of intravenous calcium gluconate and oral alfacalcidol, and a slow recovery of serum calcium. After discharge, parathyroid function recovered, and symptomatology resolved entirely in more than one month. Discussion/conclusions: We present a case involving an exceptionally large intrathyroidal parathyroid adenoma that is characterized by clinical manifestations that mimic malignancy. The identification and treatment of such tumors is challenging and requires careful preoperative evaluation and postoperative care for the risk of hungry bone syndrome.
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- 2024
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25. Federated Learning-Aided Prognostics in the Shipping 4.0: Principles, Workflow, and Use Cases
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Angelos Angelopoulos, Anastasios Giannopoulos, Nikolaos Nomikos, Alexandros Kalafatelis, Antonios Hatziefremidis, and Panagiotis Trakadas
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Federated learning ,machine learning ,maritime applications ,predictive maintenance ,Shipping 4.0 ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
The next generation of shipping industry, namely Shipping 4.0 will integrate advanced automation and digitization technologies towards revolutionizing the maritime industry. As conventional maintenance practices are often inefficient, costly, and unable to cope with unexpected failures, leading to operational disruptions and safety risks, the need for efficient predictive maintenance (PdM), relying on machine learning (ML) algorithms is of paramount importance. Still, the exchange of training data might raise privacy concerns of the involved stakeholders. Towards this end, federated learning (FL), a decentralized ML approach, enables collaborative model training across multiple distributed edge devices, such as on-board sensors and unmanned vessels and vehicles. In this work, we explore the integration of FL into PdM to support Shipping 4.0 applications, by using real datasets from the maritime sector. More specifically, we present the main FL principles, the proposed workflow and then, we evaluate and compare various FL algorithms in three maritime use cases, i.e. regression to predict the naval propulsion gas turbine (GT) measures, classification to predict the ship engine condition, and time-series regression to predict ship fuel consumption. The efficiency of the proposed FL-based PdM highlights its ability to improve maintenance decision-making, reduce downtime in the shipping industry, and enhance the operational efficiency of shipping fleets. The findings of this study support the advancement of PdM methodologies in Shipping 4.0, providing valuable insights for maritime stakeholders to adopt FL, as a viable and privacy-preserving solution, facilitating model sharing in the shipping industry and fostering collaboration opportunities among them.
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- 2024
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26. Best-of-Both-Worlds Analysis of Online Search
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Angelopoulos, Spyros, Dürr, Christoph, and Jin, Shendan
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- 2023
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27. From Groups to Communities: A Resource Mobilization Theory Perspective on the Emergence of Communities
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Angelopoulos, Spyros, Canhilal, Kubra S., and Hawkins, Matthew A.
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- 2023
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28. Serum concentrations of BDNF in adolescents with metabolic syndrome: a case-control study between normal - BMI adolescents and adolescents with obesity
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Bacopoulou, Flora, Angelopoulos, Nikolaos G., Papadodima, Stavroula, Apostolaki, Despoina, Mantzou, Aimilia, Koniari, Eleni, Efthymiou, Vasiliki, Tsitsika, Artemis, Vlachakis, Dimitrios, Charmandari, Evangelia, and Stefanaki, Charikleia
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- 2023
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29. An Experimental Assessment Using Acoustic Emission Sensors to Effectively Detect Surface Deterioration on Steel Plates
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Nikolaos Angelopoulos and Vassilios Kappatos
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acoustic emission ,sensors ,corrosion ,surface degradation monitoring ,structural health monitoring ,Chemical technology ,TP1-1185 - Abstract
Acoustic emission (AE) testing is used for the continuous evaluation of structural integrity and the monitoring of damage evolution in structural components and materials. During operation, the environmental and loading conditions of metal structures can result in corrosion and surface wear damage. The early detection of surface degradation flaws is crucial, as they can serve as local stress concentration points, leading to crack initiation and failure. In this work, the effectiveness of AE in monitoring corrosion and surface wear flaw formation was experimentally evaluated. AE sensors were installed on steel test plates during the artificial induction of corrosion and surface wear in order to detect and record the generated AE signals. Corrosion-related AE signals typically exhibit low amplitude, count, and energy values. The direct detection of active corrosion can be challenging in noisy environments, but it can be carried out under certain conditions using dedicated AE sensor groups. Surface-wear-related AE signals exhibit high amplitude, energy, and count values, with long duration values that are associated with wear and grinding conditions. It was found that AE sensors can be utilised to detect corrosion and surface degradation events. The effectiveness of the AE method in detecting surface degradation in noisy environments can be improved by implementing a filtering methodology. This will limit the recording of noise-related signals that can mask out actual surface degradation AE events.
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- 2024
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30. Assemblywomen Project (2020-2021): Helping Women in Prison to Discover Their Own Voice through Theatre
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Angelopoulos, Tasos
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The paper presents the Asseblywomen Project, conducted by Papalangki Theatre Company during 2020-2021 at the Women's Prison in Eleonas (Greece). Using as rehearsal material the comedy play "The Assemblywomen" by Aristophanes, the project aimed to encourage the participation of ex-drug addicted inmate women at the rehabilitation process, and to help their empowerment both on individual and collective level. By improvising the play's scenes, the women became more aware politically and managed to express their own thoughts and feelings.
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- 2023
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31. Exploring Syntactically Encoded Evidentiality
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Angelopoulos, Nikos, Bagioka, Dafni-Vaia, and Terzi, Arhonto
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The most recent studies on the acquisition of evidentiality, be it morphologically or syntactically encoded, have argued that the comprehension lag detected is due to factors having to do with others' authority or mental perspective, where "others" stands for other individuals involved in the experiment in various manners (e.g., the experimenter or someone in the props). However, these studies have yet to detect the age at which children eventually align with adults in comprehending the grammatical structure encoding the evidential interpretation when it is syntactically encoded. The comprehension study reported in this article has taken the aforementioned factors into consideration and has involved a large number of Greek-speaking children between second and fifth grades, along with an adult control group, to investigate syntactically encoded evidentiality. The results suggest that children align with adults in mapping source of evidence to sentence type during fourth grade, when they are 9 years old or older, suggesting that there should be additional factors behind the delayed comprehension of evidentiality. It is argued that these factors are mainly grammatical, and, most importantly, they arise to a larger extent in languages that encode evidentiality in the syntax
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- 2023
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32. Unraveling the Atmospheric Energy Input and Ionization Due To EMIC‐Driven Electron Precipitation From ELFIN Observations
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L. Capannolo, R. Marshall, W. Li, G. Berland, K. Duderstadt, N. Sivadas, D. L. Turner, and V. Angelopoulos
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atmospheric ionization ,particle precipitation ,EMIC waves ,wave‐particle interactions ,energy input ,electron loss ,Geology ,QE1-996.5 ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract Energetic electron precipitation (EEP) from the radiation belts into Earth's atmosphere leads to several profound effects (e.g., enhancement of ionospheric conductivity, possible acceleration of ozone destruction processes). An accurate quantification of the energy input and ionization due to EEP is still lacking due to instrument limitations of low‐Earth‐orbit satellites capable of detecting EEP. The deployment of the Electron Losses and Fields InvestigatioN (ELFIN) CubeSats marks a new era of observations of EEP with an improved pitch‐angle (0°–180°) and energy (50 keV–6 MeV) resolution. Here, we focus on the EEP recorded by ELFIN coincident with electromagnetic ion cyclotron (EMIC) waves, which play a major role in radiation belt electron losses. The EMIC‐driven EEP (∼200 keV–∼2 MeV) exhibits a pitch‐angle distribution (PAD) that flattens with increasing energy, indicating more efficient high‐energy precipitation. Leveraging the combination of unique electron measurements from ELFIN and a comprehensive ionization model known as Boulder Electron Radiation to Ionization (BERI), we quantify the energy input of EMIC‐driven precipitation (on average, ∼3.3 × 10−2 erg/cm2/s), identify its location (any longitude, 50°–70° latitude), and provide the expected range of ion‐electron production rate (on average, 100–200 pairs/cm3/s), peaking in the mesosphere—a region often overlooked. Our findings are crucial for improving our understanding of the magnetosphere‐ionosphere‐atmosphere system as they accurately specify the contribution of EMIC‐driven EEP, which serves as a crucial input to state‐of‐the‐art atmospheric models (e.g., WACCM) to quantify the accurate impact of EMIC waves on both the atmospheric chemistry and dynamics.
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- 2024
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33. Red Line Diffuse‐Like Aurora Driven by Time Domain Structures Associated With Braking Magnetotail Flow Bursts
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Yangyang Shen, Jun Liang, Anton Artemyev, Vassilis Angelopoulos, Qianli Ma, Larry Lyons, Jiang Liu, Yukitoshi Nishimura, Xiao‐Jia Zhang, Ivan Vasko, and Donald L. Hampton
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time domain structures ,diffuse aurora ,discrete aurora ,auroral precipitation ,red line aurora ,quasilinear diffusion ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract Magnetotail earthward‐propagating fast plasma flows provide important pathways for magnetosphere‐ionosphere coupling. This study reexamines a flow‐related red‐line diffuse‐like aurora event previously reported by Liang et al. (2011, https://doi.org/10.1029/2010ja015867), utilizing THEMIS and ground‐based auroral observations from Poker Flat. We find that time domain structures (TDSs) within the flow bursts efficiently drive electron precipitation below a few keV, aligning with predominantly red‐line auroral intensifications in this non‐substorm event. The diffuse‐like auroras sometimes coexisted with or potentially evolved from discrete forms. We forward model red‐line diffuse auroras due to TDS‐driven precipitation, employing the time‐dependent TREx‐ATM auroral transport code. The good correlation (∼0.77) between our modeled and observed red line emissions underscores that TDSs are a primary driver of the red‐line diffuse‐like auroras, though whistler‐mode wave contributions are needed to fully explain the most intense red‐line emissions.
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- 2024
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34. Global Survey of Energetic Electron Precipitation at Low Earth Orbit Observed by ELFIN
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Murong Qin, Wen Li, Xiao‐Chen Shen, Vassilis Angelopoulos, Richard Selesnick, Luisa Capannolo, Qianli Ma, Anton Artemyev, and Xiao‐Jia Zhang
- Subjects
electron precipitation ,ELFIN ,wave‐particle interaction ,radiation belt ,low Earth orbit ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract We statistically evaluate the global distribution and energy spectrum of electron precipitation at low‐Earth‐orbit, using unprecedented pitch‐angle and energy resolved data from the Electron Losses and Fields INvestigation CubeSats. Our statistical results indicate that during active conditions, the ∼63 keV electron precipitation ratio peaks at L > 6 at midnight, whereas the spatial distribution of precipitating energy flux peaks between the dawn and noon sectors. ∼1 MeV electron precipitation ratio peaks near midnight at L > ∼6 but is enhanced near dusk during active times. The energy spectrum of the precipitation ratio shows reversal points indicating energy dispersion as a function of L shell in both the slot region and at L > ∼6, consistent with hiss‐driven precipitation and current sheet scattering, respectively. Our findings provide accurate quantification of electron precipitation at various energies in a broad region of the Earth's magnetosphere, which is critical for magnetosphere‐ionosphere coupling.
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- 2024
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35. Electron Precipitation Driven by EMIC Waves: Two Types of Energy Dispersion
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Veronika S. Grach, Anton V. Artemyev, Andrei G. Demekhov, Xiao‐Jia Zhang, Jacob Bortnik, and Vassilis Angelopoulos
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EMIC waves ,wave‐particle interactions ,radiation belts ,precipitation ,relativistic electrons ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract Electromagnetic ion cyclotron (EMIC) waves can very rapidly and effectively scatter relativistic electrons into the atmosphere. EMIC‐driven precipitation bursts can be detected by low‐altitude spacecraft, and analysis of the fine structure of such bursts may reveal unique information about the near‐equatorial EMIC source region. In this study, we report, for the first time, observations of EMIC‐driven electron precipitation exhibiting energy, E, dispersion as a function of latitude (and hence L‐shell): two predominant categories exhibit dE/dL > 0 and dE/dL 0 is interpreted as due to an outward radial gradient of the equatorial magnetic field, likely produced by energetic ions freshly injected into the ring current (∼35% of the statistics). The observed energy dispersion of EMIC‐driven electron precipitation was reproduced in simulations.
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- 2024
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36. Regional Inequalities in Diagnosis and Therapies in Greece regarding Autism Spectrum Disorders
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R. Kouznetsov, P. Angelopoulos, S. Moulinos, A. Andrianopoulou, I. Dimakos, P. Gourzis, and E. Jelastopulu
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Psychiatry ,RC435-571 - Abstract
Introduction Autism spectrum disorders (ASD) represent a major public health concern on a global scale. The increasing prevalence of ASD worldwide, coupled with the arising demand for treatments, underscores its important role in the public mental health discourse. Ensuring the equitable integration of children with ASD and their families into all aspects of society becomes an imperative task, in order to eradicate the stigma associated with the broad spectrum of autism, encompassing both visible and concealed dimensions. Objectives The primary objective of this study was to determine the crude prevalence of ASD in Greece nationwide, while also examining regional disparities in both prevalence and therapies. The study spanned a three-year period from February 2019 to February 2022 and relied on retrospective data sourced from the Greek National Organization for Healthcare Services Provision (EOPYY). Methods EOPYY provided de-identified data, including information such as sex, age, diagnosis, and treatment for each child, facilitated by hashed social security numbers. Statistical analysis of the dataset was performed using the open-source statistical program R. Results A total of 18,245 children aged 2 -17 years were diagnosed with ASD in Greece, representing a nationwide crude prevalence rate of 1.16%. Regional disparities were evident, with prevalence rates ranging from 0.49% in the North Aegean to 1.57% in Crete. Over the three-year study period, a total of 15,328,327 non-medical therapies were prescribed, corresponding to an annual average of 264 therapies per child. Statistically significant differences between the thirteen regions in Greece were observed, ranging from 230 to 323 annual therapies per child. Conclusions Our findings align Greece’s ASD prevalence with the global estimate of 1 in 100 children, as per the World Health Organization. Disparities between rural and urban areas in Greece may be attributed to differences in diagnostic procedures and the availability and accessibility of specialized services for autistic individuals. Thus, the establishment of a national surveillance system for ASD is recommended to enhance our understanding of the autism spectrum, monitor changes in prevalence, and identify potential contributing factors to autism conditions. Furthermore, these evidence-based results offer invaluable insights for crafting policies concerning healthcare, education, and employment for individuals with ASD in order to ensure the development of people with autism, their wellbeing, and a good quality of life. Disclosure of Interest None Declared
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- 2024
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37. Sub‐MeV Electron Precipitation Driven by EMIC Waves Through Nonlinear Fractional Resonances
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M. Hanzelka, W. Li, M. Qin, L. Capannolo, X. Shen, Q. Ma, L. Gan, and V. Angelopoulos
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Earth's radiation belts ,EMIC waves ,resonant scattering ,nonlinear interaction ,nonresonant scattering ,electron precipitation ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract Electromagnetic ion cyclotron waves in the Earth's outer radiation belt drive rapid electron losses through wave‐particle interactions. The precipitating electron flux can be high in the hundreds of keV energy range, well below the typical minimum resonance energy. One of the proposed explanations relies on nonresonant scattering, which causes pitch‐angle diffusion away from the fundamental cyclotron resonance. Here we propose the fractional sub‐cyclotron resonance, a second‐order nonlinear effect that scatters particles at resonance order n = 1/2, as an alternate explanation. Using test‐particle simulations, we evaluate the precipitation ratios of sub‐MeV electrons for wave packets with various shapes, amplitudes, and wave normal angles. We show that the nonlinear sub‐cyclotron scattering produces larger ratios than the nonresonant scattering when the wave amplitude reaches sufficiently large values. The ELFIN CubeSats detected several events with precipitation ratio patterns matching our simulation, demonstrating the importance of sub‐cyclotron resonances during intense precipitation events.
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- 2024
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38. Methane pumping by rapidly refreezing lead ice in the ice-covered Arctic Ocean
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Ellen Damm, Silke Thoms, Michael Angelopoulos, Luisa Von Albedyll, Annette Rinke, and Christian Haas
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methane pathways in sea ice ,methane exchange at interfaces ,refrozen leads ,polar winter study ,methane isotopic signature ,central Arctic Ocean ,Science - Abstract
If and how the sea ice cycle drives the methane cycle in the high Arctic is an open question and crucial to improving source/sink balances. This study presents new insights into the effects of strong and fast freezing on the physical–chemical properties of ice and offers implications for methane fluxes into and out of newly formed lead ice. During the 2019–2020 transpolar drift of the Multidisciplinary Drifting Observatory for the Study of Arctic Climate (MOSAiC), we took weekly samples of growing lead ice and underlying seawater at the same site between January and March 2020. We analyzed concentrations and stable carbon isotopic signatures (δ13C–CH4) of methane and calculated methane solubility capacities (MSC) and saturation levels in both environments. During the first month, intense cooling resulted in the growth of two-thirds of the final ice thickness. In the second month, ice growth speed decreased by 50%. Both growth phases, disentangled, exposed different freeze impacts on methane pathways. The fast freeze caused strong brine entrapment, keeping the newly formed lead ice permeable for 2 weeks. These physical conditions activated a methane pump. An increased MSC induced methane uptake at the air–ice interface, and the still-open brine channels provided top-down transport to the ocean interface with brine drainage. When the subsurface layer became impermeable, the top-down pumping stopped, but the ongoing uptake induced a methane excess on top. During the second growth phase, methane exchange exclusively continued at the ice–ocean interface. The shift in the relative abundance of the 12C and 13C isotopes between lead ice and seawater toward a 13C-enrichment in seawater reveals brine drainage as the main pathway releasing methane from aging lead ice. We conclude that in winter, refrozen leads temporarily function as active sinks for atmospheric methane and postulate that the relevance of this process may even increase when the Arctic fully transitions into a seasonally ice-covered ocean when leads may be more abundant. To highlight the relevance of methane in-gassing at the air–ice interface as a potential but still unconsidered pathway, we include estimates of the occurrence and frequency of young lead ice from satellite observations of leads during MOSAiC.
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- 2024
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39. Price’s Law and Precise Late-Time Asymptotics for Subextremal Reissner–Nordström Black Holes
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Angelopoulos, Yannis, Aretakis, Stefanos, and Gajic, Dejan
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- 2023
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40. Minor salivary gland stem cells: a comparative study of the biological properties under clinical-grade culture conditions
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Andreadis, Dimitrios, Angelopoulos, Ioannis, Aggelidou, Elena, Gousopoulou, Evangelia, Volk, Joachim, Poulopoulos, Athanasios, Kritis, Aristeidis, Geurtsen, Werner, and Bakopoulou, Athina
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- 2023
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41. Blazing the Trail: Considering Browsing Path Dependence in Online Service Response Strategy
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Zuo, Meihua, Angelopoulos, Spyros, Liang, Zhouyang, and Ou, Carol X. J.
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- 2023
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42. The role of anti-eosinophilic therapies in eosinophilic granulomatosis with polyangiitis: a systematic review
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Kouverianos, Ioannis, Angelopoulos, Andreas, and Daoussis, Dimitrios
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- 2023
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43. Platelet-Rich Therapies in Hernia Repair: A Comprehensive Review of the Impact of Platelet Concentrates on Mesh Integration in Hernia Management
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Elissavet Anestiadou, Efstathios Kotidis, Ioanna Abba Deka, Dimitrios Tatsis, Chryssa Bekiari, Antonia Loukousia, Orestis Ioannidis, Stavros Stamiris, Konstantinos Zapsalis, Christos Xylas, Konstantinos Siozos, Christiana Chatzianestiadou, Stamatios Angelopoulos, Theodosios Papavramidis, and Angeliki Cheva
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platelet-rich plasma ,platelet-rich fibrin ,tissue regeneration ,wound healing ,incorporation ,hernia ,Microbiology ,QR1-502 - Abstract
Mesh-augmented hernia repair is the gold standard in abdominal wall and hiatal/diaphragmatic hernia management and ranks among the most common procedures performed by general surgeons. However, it is associated with a series of drawbacks, including recurrence, mesh infection, and adhesion formation. To address these weaknesses, numerous biomaterials have been investigated for mesh coating. Platelet-rich plasma (PRP) is an autologous agent that promotes tissue healing through numerous cytokines and growth factors. In addition, many reports highlight its contribution to better integration of different types of coated meshes, compared to conventional uncoated meshes. The use of PRP-coated meshes for hernia repair has been reported in the literature, but a review of technical aspects and outcomes is missing. The aim of this comprehensive review is to report the experimental studies investigating the synergistic use of PRP and mesh implants in hernia animal models. A comprehensive literature search was conducted across PubMed/Medline, Web of Science, and Scopus without chronological constraints. In total, fourteen experimental and three clinical studies have been included. Among experimental trials, synthetic, biologic, and composite meshes were used in four, nine, and one study, respectively. In synthetic meshes, PRP-coating leads to increased antioxidant levels and collaged deposition, reduced oxidative stress, and improved inflammatory response, while studies on biological meshes revealed increased neovascularization and tissue integration, reduced inflammation, adhesion severity, and mechanical failure rates. Finally, PRP-coating of composite meshes results in reduced adhesions and improved mechanical strength. Despite the abundance of preclinical data, there is a scarcity of clinical studies, mainly due to the absence of an established protocol regarding PRP preparation and application. To this point in time, PRP has been used as a coating agent for the repair of abdominal and diaphragmatic hernias, as well as for mesh fixation. Clinical application of conclusions drawn from experimental studies may lead to improved results in hernia repair.
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- 2024
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44. Evidence for lunar tide effects in Earth’s plasmasphere
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Xiao, Chao, He, Fei, Shi, Quanqi, Liu, Wenlong, Tian, Anmin, Guo, Ruilong, Yue, Chao, Zhou, Xuzhi, Wei, Yong, Rae, I. Jonathan, Degeling, Alexander W., Angelopoulos, Vassilis, Masongsong, Emmanuel V., Liu, Ji, Zong, Qiugang, Fu, Suiyan, Pu, Zuyin, Zhang, Xiaoxin, Wang, Tieyan, Wang, Huizi, and Zhang, Zhao
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- 2023
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45. The clinical significance of low dose biotin supplements
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Nicholas Angelopoulos, Rodis D. Paparodis, Ioannis Androulakis, Panagiotis Anagnostis, Anastasios Boniakos, Leonidas Duntas, Spyridon N. Karras, and Sarantis Livadas
- Subjects
BCS ,Hypothyroidism ,TFTs ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
Abstract Background In the last decade, the combination of the widespread use of streptavidin–biotin technology and biotin–containing supplements (BCS) in the daily clinical practice, have led to numerous reports of erroneous hormone immunoassay results. However, there are no studies assessing the clinical and biochemical significance of that phenomenon, when treating patients with hypothyroidism. Therefore, a prospective study was designed to investigate the potential alterations in the measurement of thyroid hormone concentrations and clinical consequences in patients with hypothyroidism using low -dose BCS containing less than 300 μg/day. Methods Fifty-seven patients on thyroxine supplementation, as a result of hypothyroidism and concurrent use of BCS at a dose
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- 2023
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46. Radiation protection measures during endourological therapies
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Lazaros Tzelves, Patrick Juliebø-Jones, Ioannis Manolitsis, Themistoklis Bellos, Ioannis Mykoniatis, Marinos Berdempes, Titos Markopoulos, Michael Lardas, Belthangady M. Zeeshan Hameed, Panagiotis Angelopoulos, Amelia Pietropaolo, Bhaskar Somani, Ioannis Varkarakis, and Andreas Skolarikos
- Subjects
Endourology ,Radiation ,Fluoroless ureteroscopy ,Percutaneous nephrolithotripsy ,As low as reasonably achievable ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Objective: The objective of this narrative review was to search the existing literature for studies reporting measures to minimize radiation use during endoscopic management of stone disease and present ways of reducing the exposure of both patients and operating room staff. Methods: A literature review in PubMed was performed to identify studies describing protocols or measures to reduce radiation received during endourological procedures from January 1970 to August 2022. Eligible studies were those that reported outcomes for ureteroscopy or percutaneous nephrolithotripsy regarding measures to minimize radiation doses used intraoperatively, performed either in real-life theatres or using phantoms. Both comparative and non-comparative studies were deemed eligible. Results: Protection can be achieved initially at the level of diagnosis and follow-up of patients, which should be done following an algorithm and choice of more conservative imaging methods. Certain protocols, which follow principles for minimized fluoroscopy use should be implemented and urologists as well as operating room staff should be continuously trained regarding radiation damage and protection measures. Wearing protective lead equipment remains a cornerstone for personnel protection, while configuration of the operating room and adjusting X-ray machine settings can also significantly reduce radiation energy. Conclusion: There are specific measures, which can be implemented to reduce radiation exposure. These include avoiding excessive use of computed tomography scans and X-rays during diagnosis and follow-up of urolithiasis patients. Intraoperative protocols with minimal fluoroscopy use can be employed. Staff training regarding dangers of radiation plays also a major role. Use and maintenance of protective equipment and setting up the operating room properly also serve towards this goal. Machine settings can be customized appropriately and finally continuously monitoring of exposure with dosimeters can be adopted.
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- 2023
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47. Frequency and Clinical Significance of Incidental Findings on CBCT Imaging: a Retrospective Analysis of Full-Volume Scans
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Charis Theodoridis, Spyros Damaskos, and Christos Angelopoulos
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clinical relevance ,cone-beam computed tomography ,dental implants ,incidental findings ,Dentistry ,RK1-715 - Abstract
Objectives: This retrospective study aims to identify incidental findings in cone-beam computed tomography scans of patients irradiated for preoperative evaluation for implant placement and obtained using the same imaging unit as well as the same field of view. The incidence of each incidental finding, as well as the overall incidence, were calculated and the findings were ranked according to their clinical significance. Material and Methods: A total of 741 cone-beam computed tomography (CBCT) examinations with extended field of view (15 x 15 cm) were retrospectively evaluated for incidental findings (IFs). These were identified, recorded, classified as to their location, and ranked according to their clinical significance. Results: The vast majority of CBCT examinations presented at least one IF, resulting in a surprisingly high prevalence in total. If extreme anatomical variants are considered (nasal septum deviation, sinus septations etc.), the cumulative prevalence exceeds 99%. IFs of major significance, that may require immediate attention, are beyond 10% in frequency. Conclusions: We found high prevalence of incidental findings on cone-beam computed tomography examinations performed for preoperative evaluation for implant placement (99.5% if anatomical variants included). Most incidental findings were of minor significance. Although the number of incidental findings that require immediate attention is relatively low, there is a considerable number of cases that need periodic evaluation and/or referral.
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- 2024
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48. Ureteral stent related symptoms: A comparative study
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Themistoklis Ch. Bellos, Ioannis S. Manolitsis, Stamatios N. Katsimperis, Panagiotis A. Angelopoulos, Sotirios G. Kapsalos-Dedes, Panagiotis K. Deligiannis, Lazaros I. Tzelves, Nikolaos A. Kostakopoulos, Iraklis C. Mitsogiannis, Ioannis M. Varkarakis, Athanasios G. Papatsoris, Andreas A. Skolarikos, and Charalampos N. Deliveliotis
- Subjects
Pigtails ,Urinary symptoms ,Hematuria ,Pigtail characteristics ,Ureteral stent ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Background: In urology, ureteral stents are used to treat obstructive diseases. Hematuria (54%), fever, discomfort, and lower urinary system symptoms are the predominant symptoms related to ureteral stent. Aim: This article links stent symptoms to double-j width and length, as well as patient’s height, weight, and body mass index (BMI). Ureteric Stent Symptoms Questionnaire (USSQ) was used to measure ureteral stent symptoms at 1st and 4th week of stent in situ as well as the 4th week after pigtail removal. Methods: A 200-patient prospective study, where patients were allocated into four groups following ureteral stent insertion depending on the stent characteristics. Those groups were: 4.8 Fr./26 cm (Group A), 4.8 Fr./28 cm (Group B), 6 Fr/26 cm (Group C), and 6 Fr/28 cm (Group D). Results: Men comprised 53.5% of 200 patients. Participants had an average age of 49 ± 15.5 years, height of 175 ± 8.94 cm, and BMI of 23.8 ± 7.6 cm. The laboratory results were identical between groups. At the first and fourth week, groups had similar urine symptoms, pain severity, health status and occupational activities. The difference in pain location was statistically significant. Group A had 82.4% renal back pain in the first week, whereas Group B had 68.8%, Group C 31.3% and Group D 62.5 (p = 0.04). At the fourth week, 64.7% of Group A patients reported kidney front pain, compared to 100% of Group B, 93.3% of Group C, and 100% of Group D (p = 0.04). There was statistical significance in the sexual activity of the patients. 24.4% of Group C patients stopped sexual activity before stent installation, compared to 10.6%, 8.3%, and 6.4% of the other groups (p = 0.03). A moderate percentage of patients had active sexual activity at week 4 (Group A: 7.8%, Group B: 5.8%, Group C: 8.2%, Group D: 4.1%), p = 0.83. In multivariate analysis, urinary catheter group, age, weight, height, and BMI did not significantly affect urine index score (UIS), pain index score (PIS), general health (GH), quality of work (QW), and quality of sex (QS). Conclusions: Despite various attempts to establish the best ureteral stent, the effect of double-j stent physical features on stent-related symptoms remained unknown. No verdict is conceivable without adequate empirical data.
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- 2024
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49. Energetic Particle Precipitation in Sub‐Auroral Polarization Streams
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Anton V. Artemyev, Ying Zou, Xiao‐Jia Zhang, Xing Meng, and Vassilis Angelopoulos
- Subjects
sub‐auroral polarization streams ,relativistic electrons ,EMIC waves ,magnetosphere‐ionosphere coupling ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract Sub‐auroral polarization streams (SAPS) are one of the most intense manifestations of magnetosphere‐ionosphere coupling. Magnetospheric energy transport to the ionosphere within SAPS is associated with Poynting flux and the precipitation of thermal energy (0.03–30 keV) plasma sheet particles. However, much less is known about the precipitation of high‐energy (≥50 keV) ions and electrons and their contribution to the low‐altitude SAPS physics. This study examines precipitation within one SAPS event using a combination of equatorial THEMIS and low‐altitude DMSP and ELFIN observations, which, jointly, cover from a few eV up to a few MeV energy range. Observed SAPS are embedding the ion isotropy boundary, which includes strong 300–1,000 keV ion precipitation. SAPS are associated with intense precipitation of relativistic electrons (≤3 MeV), well equatorward of the electron isotropy boundary. Such relativistic electron precipitation is likely due to electron scattering by electromagnetic ion cyclotron waves at the equator.
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- 2024
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50. Revisiting the universality law in magnetically detected residual stresses in steels
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Eleni Mangiorou, Tatiana V. Damatopoulou, Spyridon Angelopoulos, Konstantinos Kalkanis, Polyxeni Vourna, Aphrodite Ktena, and Evangelos Hristoforou
- Subjects
Physics ,QC1-999 - Abstract
The dependence of residual stresses on differential permeability, determining the so called Magnetic Stress Calibration (MASC) curve, results in the Universal MASC curve after normalizing the stress and permeability axes with the yield stress and the maximum differential permeability of the steel under test, respectively. The motivation of this paper is to illustrate the ability of obtaining the MASC curve of an unknown steel just by measuring its yield stress and maximum differential permeability. The calculated MASC curve of an unknown type of steel, obtained by multiplying the stress and permeability axes of the Universal MASC curve with the yield stress and maximum differential permeability obtained by the stress-strain curve under simultaneous measurement of the permeability, was compared with the actual MASC curve of the same unknown type of steel determined by the classical method, with an agreement better than ±5%. The conclusion is that the actual MASC curve of an unknown type of steel can be determined just by a stress-strain measurement, with simultaneous determination of the maximum amplitude of the differential permeability.
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- 2024
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