280 results on '"Dellis P"'
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2. The existence of Indonesian language: Pidgin or Creole
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Dellis Pratika
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indonesian language ,malay language ,pidgin ,creole ,English language ,PE1-3729 - Abstract
Indonesian language or sometimes called Bahasa is the national language of Indonesia. It was derived from Malay language and established as a national language in 1928. Until now, the Indonesian language keeps borrowing words from other languages. It was questioned whether the language was actually a pidgin that authorized into a creole since it was not only contained of Malay language but also languages that it was made contact with since colonialism eras, such as Dutch, English, Arabic, and other languages. This research used library study to find the data since it was not possible to trace the data in the field. This study was aimed to determine whether the Indonesian language was categorized into pidgin or creole. The result of the study revealed that Indonesian was not either pidgin or creole since the characteristics features did not meet any of them. It is believed that the Indonesian language was one of the means to achieve independence, but it is opened to receive lexicons from other foreign languages as the words keep increasing each year that can be seen in Kamus Besar Bahasa Indonesia (KBBI).
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- 2016
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3. Cavitation shapes measurements in piston-ring lubrication and their link to lubricant properties
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Dellis Polychronis
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Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
The emissions control regulations introduced by governments are set to improve engine quality and reduce the impact automobiles have on the planet. The regulations imposed on the manufactures have proven very difficult to meet. To this effect some of the leading names in the industry were pushed to invest significant funding in research, development and optimisation of combustion, powertrain and tribology inside the ICE. Their goal is reduction of fuel consumption and emissions while increasing performance and durability. The piston-ring and cylinder-liner interaction is the major source of frictional losses for reciprocating ICEs and so, it is important to avoid any failure of piston-rings to effectively control lubricant transport from the sump onto the cylinder walls and further to the combustion chamber. This lubricant will participate in the emissions through absorption and desorption of fuel in the oil film at the cylinder walls, also resulting in lubricant contamination and consumption. The objective of this project is to assist with the investigation of phenomena occurring in the cylinder liner and piston-ring interaction under different operating conditions. The following investigations have been carried out, flow and cavitation visualisation in a model lubricant rig and cavitation visualisation in a newly designed optical engine.
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- 2021
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4. Representational Tenets for Memory Athletics
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Schmidt, Kevin, Larue, Othalia, Kulhanek, Ray, Flaute, Dylan, Veliche, Razvan, Manasseh, Christian, Dellis, Nelson, Clouse, Scott, Culbertson, Jared, and Rogers, Steve
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Quantitative Biology - Neurons and Cognition ,Computer Science - Artificial Intelligence - Abstract
We describe the current state of world-class memory competitions, including the methods used to prepare for and compete in memory competitions, based on the subjective report of World Memory Championship Grandmaster and co-author Nelson Dellis. We then explore the reported experiences through the lens of the Simulated, Situated, and Structurally coherent Qualia (S3Q) theory of consciousness, in order to propose a set of experiments to help further understand the boundaries of expert memory performance.
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- 2023
5. The effect of friction force and cavitation on wear in piston-cylinder assemblies
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Dellis Polychronis
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Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Both in engines and test rigs, cavitation in piston-ring lubrication is a subject studied by many researchers in the past. Although there is no sufficient evidence of cavitation erosion on the surface of the liner, this phenomenon is studied as part of the lubricant transport process. During the transport process the lubricant enters the combustion chamber. The combustion products of consumed oil might contribute to exhaust gas emissions and with emission legislation becoming more stringent, it is important that oil consumption is reduced to the lowest level possible. The role of the piston-rings is becoming more complex with the imposed requirements for lower oil consumption and friction. The piston-ring pack role on engine performance, durability and wear, is becoming on the other hand, more demanding. Between the piston-ring and cylinder liner, cavitation occurs as a result of two-phase liquid flow. Cavitation has long been recognized to degrade performances in most engineering applications and its effect in piston-ring lubrication is that it alters the oil film pressure profile, generated at the converging-diverging wedge of the piston-ring. An area of the piston-ring surface is void, corresponds to subatmospheric pressures and thus, the piston-ring load capacity is altered. Two experimental rigs were used, a simplified single-ring test rig that simulates the piston-ring liner movement at speeds corresponding to idle but the movement is reversed and a single cylinder diesel engine that was used for visualization results only, after the necessary modifications.
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- 2018
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6. Management of urinary stones: state of the art and future perspectives by experts in stone disease
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Athanasios Papatsoris, Alberto Budia Alba, Juan Antonio Galán Llopis, Murtadha Al Musafer, Mohammed Alameedee, Hammad Ather, Juan Pablo Caballero-Romeu, Antònia Costa-Bauzá, Athanasios Dellis, Mohamed El Howairis, Giovanni Gambaro, Bogdan Geavlete, Adam Halinski, Bernhard Hess, Syed Jaffry, Dirk Kok, Hichem Kouicem, Luis Llanes, Juan M. Lopez Martinez, Elenko Popov, Allen Rodgers, Federico Soria, Kyriaki Stamatelou, Alberto Trinchieri, and Christian Tuerk
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Urinary calculi ,percutaneous nephrolithotomy ,retrograde intrarenal lithotripsy ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Aim: To present state of the art on the management of urinary stones from a panel of globally recognized urolithiasis experts who met during the Experts in Stone Disease Congress in Valencia in January 2024. Options of treatment: The surgical treatment modalities of renal and ureteral stones are well defined by the guidelines of international societies, although for some index cases more alternative options are possible. For 1.5 cm renal stones, both m-PCNL and RIRS have proven to be valid treatment alternatives with comparable stone-free rates. The m-PCNL has proven to be more cost effective and requires a shorter operative time, while the RIRS has demonstrated lower morbidity in terms of blood loss and shorter recovery times. SWL has proven to be less effective at least for lower calyceal stones but has the highest safety profile. For a 6mm obstructing stone of the pelviureteric junction (PUJ) stone, SWL should be the first choice for a stone less than 1 cm, due to less invasiveness and lower risk of complications although it has a lower stone free-rate. RIRS has advantages in certain conditions such as anticoagulant treatment, obesity, or body deformity. Technical issues of the surgical procedures for stone removal: In patients receiving antithrombotic therapy, SWL, PCN and open surgery are at elevated risk of hemorrhage or perinephric hematoma. URS, is associated with less morbidity in these cases. An individualized combined evaluation of risks of bleeding and thromboembolism should determine the perioperative thromboprophylactic strategy. Pre-interventional urine culture and antibiotic therapy are mandatory although UTI treatment is becoming more challenging due to increasing resistance to routinely applied antibiotics. The use of an intrarenal urine culture and stone culture is recommended to adapt antibiotic therapy in case of postoperative infectious complications. Measurements of temperature and pressure during RIRS are vital for ensuring patient safety and optimizing surgical outcomes although techniques of measurements and methods for data analysis are still to be refined. Ureteral stents were improved by the development of new biomaterials, new coatings, and new stent designs. Topics of current research are the development of drug eluting and bioresorbable stents. Complications of endoscopic treatment: PCNL is considered the most invasive surgical option. Fever and sepsis were observed in 11 and 0.5% and need for transfusion and embolization for bleeding in 7 and 0.4%. Major complications, as colonic, splenic, liver, gall bladder and bowel injuries are quite rare but are associated with significant morbidity. Ureteroscopy causes less complications, although some of them can be severe. They depend on high pressure in the urinary tract (sepsis or renal bleeding) or application of excessive force to the urinary tract (ureteral avulsion or stricture). Diagnostic work up: Genetic testing consents the diagnosis of monogenetic conditions causing stones. It should be carried out in children and in selected adults. In adults, monogenetic diseases can be diagnosed by systematic genetic testing in no more than 4%, when cystinuria, APRT deficiency, and xanthinuria are excluded. A reliable stone analysis by infrared spectroscopy or X-ray diffraction is mandatory and should be associated to examination of the stone under a stereomicroscope. The analysis of digital images of stones by deep convolutional neural networks in dry laboratory or during endoscopic examination could allow the classification of stones based on their color and texture. Scanning electron microscopy (SEM) in association with energy dispersive spectrometry (EDS) is another fundamental research tool for the study of kidney stones. The combination of metagenomic analysis using Next Generation Sequencing (NGS) techniques and the enhanced quantitative urine culture (EQUC) protocol can be used to evaluate the urobiome of renal stone formers. Twenty-four hour urine analysis has a place during patient evaluation together with repeated measurements of urinary pH with a digital pH meter. Urinary supersaturation is the most comprehensive physicochemical risk factor employed in urolithiasis research. Urinary macromolecules can act as both promoters or inhibitors of stone formation depending on the chemical composition of urine in which they are operating. At the moment, there are no clinical applications of macromolecules in stone management or prophylaxis. Patients should be evaluated for the association with systemic pathologies. Prophylaxis: Personalized medicine and public health interventions are complementary to prevent stone recurrence. Personalized medicine addresses a small part of stone patients with a high risk of recurrence and systemic complications requiring specific dietary and pharmacological treatment to prevent stone recurrence and complications of associated systemic diseases. The more numerous subjects who form one or a few stones during their entire lifespan should be treated by modifications of diet and lifestyle. Primary prevention by public health interventions is advisable to reduce prevalence of stones in the general population. Renal stone formers at "high-risk" for recurrence need early diagnosis to start specific treatment. Stone analysis allows the identification of most “high-risk” patients forming non-calcium stones: infection stones (struvite), uric acid and urates, cystine and other rare stones (dihydroxyadenine, xanthine). Patients at “high-risk” forming calcium stones require a more difficult diagnosis by clinical and laboratory evaluation. Particularly, patients with cystinuria and primary hyperoxaluria should be actively searched. Future research: Application of Artificial Intelligence are promising for automated identification of ureteral stones on CT imaging, prediction of stone composition and 24-hour urinary risk factors by demographics and clinical parameters, assessment of stone composition by evaluation of endoscopic images and prediction of outcomes of stone treatments. The synergy between urologists, nephrologists, and scientists in basic kidney stone research will enhance the depth and breadth of investigations, leading to a more comprehensive understanding of kidney stone formation.
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- 2024
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7. Chromium agglomeration induced by Fe+ ion irradiation of Fe-10at%Cr
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S. Pantousa, A.J. London, K. Mergia, A. Ionescu, E. Manios, P. Tsavalas, S. Dellis, C. Kinane, S. Langridge, A. Caruana, U. Kentsch, and S. Messoloras
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Fe-Cr alloys ,Ion irradiation ,Cr depletion ,Polarized neutron reflectivity ,Atom probe tomography ,Nuclear engineering. Atomic power ,TK9001-9401 - Abstract
Fe-Cr alloys serve as model alloys for the investigation of radiation induced effects in ferritic-martensitic steels which are candidate structural materials for future fusion reactors. In this work the effect of Cr segregation and/or agglomeration in 490 keV Fe+ ion irradiated Fe-10at%Cr alloys in the form of thin films is investigated. The irradiations took place at 300 °C at doses ranging from 0.5 to 20 displacements per atom (dpa). Polarized Neutron Reflectivity (PNR) measurements were used for the determination of the solute Cr concentration in the Fe-Cr matrix. Cr depletion from the Fe-Cr matrix up to 2.4 at% was found. This is related to solute Cr decrement as the accumulated dose increases. After the damage of 4 dpa, solute Cr reaches the asymptotic value of 8.4 at%, close to that of the thermodynamic equilibrium in Fe-Cr. Atom Probe Tomography (APT) measurements showed that after irradiation Cr accumulates into clusters the majority of which is co-located with oxygen.
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- 2024
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8. Innovations for Holistic and Sustainable Transitions
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Phoebe Koundouri, Angelos Alamanos, Stathis Devves, Conrad Landis, and Kostantinos Dellis
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energy ,energy policy ,integrated modelling ,Global Climate Hub ,system innovation approach ,stakeholder participation ,Technology - Abstract
Energy system planning has evolved from a narrow focus on engineering and supply works towards addressing more complex, multifactorial challenges. Increasingly challenged by climate change, extreme events, economic shocks, and altered supply demand patterns, the analysis of energy systems requires holistic approaches based on data-driven models, taking into account key socio-economic factors. We draw insights from reviewing the literature, indicating the need to cover the following major gaps: the shift to transdisciplinary approaches, incorporating environmental system analysis; resilient and sustainable energy designs based on flexible portfolios of renewable mixes; the integration of socio-economic aspects, economic analyses and behavioural models to ensure energy systems are not only technically sound but socially acceptable and viable; the need for stakeholder engagement considering the human angle in energy security and behavioural shifts. Responding to these pressing challenges and emerging needs, the Global Climate Hub (GCH) initiative, operating under the UN Sustainable Development Solutions Network, offers a conceptual framework, leveraging transdisciplinary approaches. In this Concept Paper, we present for the first time the idea of the GCH as a framework that we believe has the potential to address the modern holistic needs for energy system analysis and policymaking. By setting the conceptual/theoretical ground of our suggested approach, we aim to provide guidance for innovative combinations of cutting-edge models, socio-economic narratives, and inclusive interaction with relevant stakeholders for the development and the long-term implementation of sustainable pathways.
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- 2024
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9. Wear Metal Concentrations Used for Enhancing Spectrometric Oil Analysis Method Credibility and Statistical Feedback - A Step Towards Big Data Analysis
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Polychronis S. Dellis
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spectrometric oil analysis ,lubricant sampling ,diagnosis ,wear metals ,friction ,aircraft engines/gearboxes ,engine maintenance procedures ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
The well-established oil condition monitoring tool of spectrometric oil analysis is used to expand previous published experimental analysis with a view to enhancing multiple wear metal elements study in numerous different applications. This study includes gas turbine engines, piston engines, turboprop and turboshaft engines and helicopter gearbox assemblies. The database used in the original study was enhanced with numerous applications that were used to establish the credibility of spectrometric oil analysis as an important diagnostic tool. The importance of the method lies in its ability to locate unusual concentrations of a metal element that is translated as an indication of abnormal wear of the equipment under scrutiny. The operator benefits from major failures avoidance and taking correct decisions regarding equipment maintenance and servicing or repairing, can also profit from economic factors rationality during equipment operation. Lubricant quality, identification or imminent failures, prolonged life cycle and acquisition of statistical data are conditions that emanate from the correct interpretation of the results that in turn, can avoid human lives and equipment losses due to major incidents.
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- 2023
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10. The electrocaloric response in Lanthanum-modified lead zirconate titanate ceramic
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Asbani, B., Dellis, J. -L., Lahmar, A., Amjoud, M., Gagou, Y., Mezzane, D., Kutnjak, Z., Pirc, R., Marssi, M. El, and Rožič, B.
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Condensed Matter - Materials Science - Abstract
Over the past decades, there has been significant interest in new cooling technology based on the electrocaloric effect. The large electrocaloric effect observed in polymeric and inorganic ferroelectric materials made possible development of dielectric cooling devices of a new generation. We report a significant impact of annealing on the electrocaloric effect observed in 12/65/35 PLZT bulk ceramics. The electrocaloric data were obtained by direct measurements. Electrocaloric results confirm the existence of the significant electrocaloric response in this relaxor ferroelectric PLZT composition exceeding previously obtained electrocaloric values in perovskite relaxor ferroelectrics such as PMN-PT and x/65/35 PLZT ceramics., Comment: arXiv admin note: text overlap with arXiv:2006.05079
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- 2020
11. Complex impedance and Raman spectroscopy of Na$_{0.5}$(Bi$_{1-x}$Dy$_x$)$_{0.5}$TiO$_3$ ceramics
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Benyoussef, Manal, Zannen, Moneim, Belhadi, Jamal, Manoun, Bouchaib, Dellis, Jean-Luc, Lahmar, Abdelilah, and Marssi, Mimoun El
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Condensed Matter - Materials Science - Abstract
In this work structural refinement, complex impedance spectroscopy, and Raman spectroscopy have been investigated on Na$_{0.5}$(Bi$_{1-x}$Dy$_x$)$_{0.5}$TiO$_3$ (xDyNBT) ceramic systems. The pure NBT, 2DyNBT and 5DyNBT compounds crystallize in a rhombohedral structure while the 15DyNBT composition crystallizes in an orthorhombic Pnma structure. We reported that dysprosium addition affects the phase transition temperatures as well as the dielectric losses. The electrical transport at high temperatures was investigated using the CIS over a wide frequency range. The studied samples showed a non-Debye type process, with a short-range relaxation for the pure NBT and a coexistence of both localized and long-range relaxations of charge carriers for the 2DyNBT and 5DyNBT compounds. For the high concentration, 15DyNBT, a short-range relaxation is observed. Moreover, using a brick-layer model we discuss the resistance and capacitance of the different contributors (grain and grain boundaries) in our samples. High temperature Raman spectroscopy investigation was performed in order to follow the temperature evolution of the structural transformations on ferroelectric compounds. Anomalies in the temperature evolution of the vibrational modes are seen to correlate well with the temperature transitions observed from dielectric measurements.
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- 2020
12. Electrocaloric response in Lanthanum-modified lead zirconate titanate ceramics
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Asbani, B., Marssi, M. El, Dellis, J. -L., Lahmar, A., Gagou, Y., Mezzane, D., Amjoud, M., Alimoussa, A., Kutnjak, Z., Pirc, R., and Rožič, B.
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Condensed Matter - Materials Science - Abstract
Recent findings of a large electrocaloric (EC) effect in polymeric and inorganic ferroelectric materials open a potential possibility of development of solid-state cooling or heating devices of new generation with better energy efficiency that may be less harmful for the environment. We investigate by using direct measurements, the temperature and electric field dependence of the electrocaloric response in Pb1-xLax(ZryTi1-y)1-x/4O3 bulk ceramics (PLZT) with x=0.06 and 0.12. Here, the properties of the EC response were probed in a part of the PLZT composition phase diagram with low y=0.40 composition, in which the EC effect was not previously studied. Measurement results show the existence of the sizeable EC response in 12/40/60 PLZT sample with the EC temperature change ({\Delta}TEC) of 2.92 K at 430 K and 80 kV/cm. This value exceeds previously obtained {\Delta}TEC values in relaxor ferroelectric x/65/35 PLZT compositions and rivaling the best EC response in lead magnesium niobate-lead titanate ceramics. The electrocaloric responsivity ({\Delta}T/{\Delta}E) value of 0.41x10-6 Km/V determined at a lower electric field of 20 kV/cm and 410 K is comparable to those observed in other perovskite ferroelectrics.
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- 2020
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13. Laser cooling in a chip-scale platform
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McGilligan, J. P., Moore, K. R., Dellis, A., Martinez, G. D., de Clercq, E., Griffin, P. F., Arnold, A. S., Riis, E., Boudot, R., and Kitching, J.
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Physics - Atomic Physics ,Physics - Instrumentation and Detectors ,Physics - Optics - Abstract
Chip-scale atomic devices built around micro-fabricated alkali vapor cells are at the forefront of compact metrology and atomic sensors. We demonstrate a micro-fabricated vapor cell that is actively-pumped to ultra-high-vacuum (UHV) to achieve laser cooling. A grating magneto optical trap (GMOT) is incorporated with the 4 mm-thick Si/glass vacuum cell to demonstrate the feasibility of a fully-miniaturized laser cooling platform. A two-step optical excitation process in rubidium is used to overcome surface-scatter limitations to the GMOT imaging. The unambiguous miniaturization and form-customizability made available with micro-fabricated UHV cells provide a promising platform for future compact cold-atom sensors., Comment: 5 pages, 3 figures
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- 2020
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14. Genotyping and Molecular Characterization of VP6 and NSP4 Genes of Unusual Rotavirus Group A Isolated from Children with Acute Gastroenteritis
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Charilaos Dellis, Elizabeth-Barbara Tatsi, Dimitra-Maria Koukou, Filippos Filippatos, Evangelia-Eirini Vetouli, Emmanouil Zoumakis, Athanasios Michos, and Vasiliki Syriopoulou
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Microbiology ,QR1-502 - Abstract
Group A rotavirus (RVA), which causes acute gastroenteritis (AGE) in children worldwide, is categorized mainly based on VP7 (genotype G) and VP4 (genotype P) genes. Genotypes that circulate at
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- 2024
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15. Human Security: Concepts and Measurement
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Phoebe Koundouri and Konstantinos Dellis
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peace and security ,law and governance ,new economics ,sustainable development ,education ,knowledge ,science and values ,International relations ,JZ2-6530 ,Economic growth, development, planning ,HD72-88 - Abstract
The notion of Human Security has regained traction in the public domain, mostly following the disruptive impact of the global pandemic and the geopolitical tensions in Eastern Europe. The concept, however, was molded during the second half of the twentieth century, as scholars, policy makers and the public became ever more disillusioned with the focus on national security that dominated the public domain. The pressing issues of climate change, health challenges and human rights violations in the 21st century have resulted in elevated policy attention and resources for these issues in the form of targeted reports, concepts, metrics, empirical and theoretical research. Having said that, the introduction, monitoring and implementation of the SDGs within the UN 2030 Agenda are inherently related to the concept of Human Security and its components. This paper attempts to briefly present the various metrics and reports germane to Human Security. We undertake a general-to-specific approach to identify the measures, variables, and indicators, which are relevant to the concept of Human Security and its sub-categories. These variables and indicators derive from selected Indicators and Trends from UNHDR, Fragile States Index (FFP), Corruption Perception Index (Transparency International), Biodiversity Habitat Index and CO2 exposure (Environmental Performance Index), Ecological Threat Index (Institute for Economics and Peace) and Healthy Life Expectancy (WHO). Then, we conceptually map the indicators to the measurement and implementation of the Sustainable Development Goals (SDGs) using data available from the UN SDSN Sustainable Development Report.
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- 2023
16. Epidemiological study of unusual rotavirus strains and molecular characterization of emerging P[14] strains isolated from children with acute gastroenteritis during a 15-year period
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Tatsi, Elizabeth-Barbara, Koukou, Dimitra-Maria, Dellis, Charilaos, Dourdouna, Maria-Myrto, Efthymiou, Vasiliki, Michos, Athanasios, and Syriopoulou, Vasiliki
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- 2023
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17. SARS-CoV-2 seroepidemiological study in healthcare workers and discordant results using seven different diagnostic methods
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Tatsi, Elizabeth-Barbara, Dellis, Charilaos, Petridou, Evangelia, Banou, Kirkira, Zachariadou, Levantia, Syriopoulou, Vassiliki, and Michos, Athanasios
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- 2022
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18. Post neutron irradiation annealing and defect evolution in single crystal tungsten
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D. Papadakis, K. Mergia, E. Manios, V. Chatzikos, S. Dellis, and S. Messoloras
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Radiation damage ,Tungsten single crystal ,Post-irradiation annealing ,Positron annihilation lifetime spectroscopy ,Electrical resistivity ,Hardness ,Nuclear engineering. Atomic power ,TK9001-9401 - Abstract
Single crystal W is offered for Physics understanding of irradiation induced defects and their annealing as its structure is well defined and it is almost defect free. W(100) single crystal was neutron irradiated to a damage of 0.11 displacements per atom at 600 °C and subsequently isochronally annealed from 700 up to 1500 °C in 100 °C steps. Irradiation causes the formation of dislocation loops and vacancy clusters and a 45 % increase in hardness. After the annealing of 1500 °C the positron lifetime annihilation spectrum shows a defect free material and its hardness has been reverted to the pre-irradiation value and only clusters of Re, WRe and WOs2 have been detected by grazing incidence X-ray diffraction. The total line density of dislocations, number density of voids and their size versus annealing temperature have been determined. From hardness, the critical resolved stresses arising from dislocations and voids have been derived and correlated with their densities. The kinetics of defect annihilation versus annealing temperature is discussed.
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- 2023
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19. Association of clinical and epidemiological characteristics with COVID-19 BNT162b2 mRNA vaccine short-term adverse reactions in healthcare workers
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Filippos Filippatos, Elizabeth-Barbara Tatsi, Charilaos Dellis, Nick Dessypris, Vassiliki Syriopoulou, and Athanasios Michos
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healthcare worker ,biontech ,mrna ,vaccine ,adverse reactions ,Immunologic diseases. Allergy ,RC581-607 ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Introduction The aim of the study was to investigate the prevalence and severity of adverse reactions (ARs) after immunization of healthcare workers (HCWs) with BNT162b2 vaccine and to associate them with clinical and epidemiological characteristics. Methods A form containing demographic and clinical data as well as ARs after both doses of the vaccine was completed, and statistical association analysis was performed. Results A total of 502 HCWs (females 78.3%) with mean age (±SD) 48.17 years (±12.97) participated. After the first dose, 404 (80.5%) HCWs reported at least one local AR (LAR) and 366 (72.9%) after the second dose (p-value=0.004). After the first dose, 121 (24.1%) HCWs reported at least one systemic AR (SAR) and 275 (54.8%) after the second dose (p-value
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- 2021
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20. Rapid laser-induced photochemical conversion of sol-gel precursors to In2O3 layers and their application in thin-film transistors
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Dellis, S., Isakov, I., Kalfagiannis, N., Tetzner, K., Anthopoulos, T. D., and Koutsogeorgis, D. C.
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Condensed Matter - Materials Science - Abstract
We report the development of indium oxide (In2O3) transistors via a single step laser-induced photochemical conversion process of a sol-gel metal oxide precursor. Through careful optimization of the laser annealing conditions we demonstrated successful conversion of the precursor to In2O3 and its subsequent implementation in n-channel transistors with electron mobility up to 13 cm2/Vs. Importantly, the process does not require thermal annealing making it compatible with temperature sensitive materials such as plastic. On the other hand, the spatial conversion/densification of the sol-gel layer eliminates additional process steps associated with semiconductor patterning and hence significantly reduces fabrication complexity and cost. Our work demonstrates unambiguously that laser-induced photochemical conversion of sol-gel metal oxide precursors can be rapid and compatible with large-area electronics manufacturing.
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- 2017
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21. Corrigendum to 'Recognition motifs for importin 4 [(L)PPRS(G/P)P] and importin 5 [KP(K/Y)LV] binding, identified by bio-informatic simulation and experimental in vitro validation' [Comput Struct Biotechnol J 20 (2022) 5952–5961]
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Athanasios A. Panagiotopoulos, Konstantina Kalyvianaki, Paraskevi K. Tsodoulou, Maria N. Darivianaki, Dimitris Dellis, George Notas, Vangelis Daskalakis, Panayiotis A. Theodoropoulos, Christos A. Panagiotidis, Elias Castanas, and Marilena Kampa
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Biotechnology ,TP248.13-248.65 - Published
- 2023
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22. Transcutaneous dorsal penile nerve stimulation for the treatment of premature ejaculation: A novel technique
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Mohamad Moussa, Mohamad Abou Chakra, Baraa Dabboucy, Youssef Fares, Athanasios Dellis, and Athanasios Papatsoris
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Diseases of the genitourinary system. Urology ,RC870-923 - Published
- 2022
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23. Kinetics of SARS-CoV-2 Spike Antibodies after the Second and Third Dose of the BNT162b2 COVID-19 Vaccine and Association with Epidemiological Characteristics and Breakthrough Infection in a Cohort Study of Healthcare Workers
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Elizabeth-Barbara Tatsi, Filippos Filippatos, Charilaos Dellis, Maria-Myrto Dourdouna, Vasiliki Syriopoulou, and Athanasios Michos
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SARS-CoV-2 ,COVID-19 ,BNT162b2 ,immunity ,vaccination ,breakthrough infection ,Biology (General) ,QH301-705.5 - Abstract
To prospectively study the kinetics of immune responses after immunization with the BNT162b2 mRNA COVID-19 vaccine and their association with epidemiological parameters and breakthrough infection (BI), we measured total (TAbs-WT) and neutralizing antibodies against wild-type (NAbs-WT) and Omicron (NAbs-O) SARS-CoV-2 spike proteins in healthcare workers (HCWs) after the second (4 and 8 months) and third dose (1 and 8 months). Vaccinated HCWs (n = 486), with a median age (IQR) of 49 years (38–56), were included in this prospective cohort study. BI was observed 4 and 8 months after the second dose in 8/486 (1.6%) and 15/486 (3.1%) HCWs, respectively, and 1 and 8 months after the third dose in 17/486 (3.5%) and 152/486 (31.3%) HCWs, respectively. A comparison of immune responses 1 month after the third dose in vaccinated HCWs without a BI or with a BI in the next 7 months did not detect any statistically significant differences in the TAbs-WT (median (IQR): 16,611.0 (13,011.0) U/mL vs. 17,572.5 (14,501.0) U/mL, p = 0.529) and NAbs-WT (median (IQR): 96.5% (1.7) vs. 96.7% (1.9), p = 0.555). After infection, HCWs with a BI had significantly increased TAbs-WT levels at all time points compared to healthy HCWs. The findings of the present study indicate that antibody levels after three doses of the BNT162b2 vaccine are not directly associated with the possibility of a BI.
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- 2023
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24. Relugolix for the treatment of prostate cancer
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Stamatakos, Panagiotis Velissarios, Papavasileiou, Georgios, Leventi, Aggeliki, Papatsoris, Athanasios, Bamias, Aristotelis, Dellis, Athanasios, and Fragkoulis, Charalampos
- Abstract
ABSTRACTIntroductionAndrogen deprivation therapy consists of the cornerstone of prostate cancer medical treatment. Until recently, castration of hypothalamus-hypophysis-gonadal axial was based on injectable medical agents. A few years ago, a novel per os administered GnRH antagonist was approved leading testosterone to castration level. Relugolix was approved by FDA in 2020, and it is the first per os administered GnRH antagonist. The present study is a literature review of the efficacy, safety and clinical perspectives of relugolix.Areas coveredA literature narrative review was conducted using PubMed/MEDLINE, Scopus, and the Cochrane library. Studies written in English language, considering efficacy, safety and cost-effectiveness of relugolix compared with other androgen deprivation therapies were included in the review.Expert opinionRecent studies have examined efficacy of relugolix revealing a testosterone suppression percentage of 78.4% after 48 weeks from treatment initiation. Moreover, relugolix has been associated with less major cardiovascular events as well as better rate of testosterone recovery after treatment completion compared with the GnRH agonists. However, there is no head-to-head trial comparing relugolix with injectable GnRH antagonists, so far. As a result, a trial comparing the methods of antagonists’ administration should be performed in the future.
- Published
- 2024
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25. B3 agonists or anticholinergics in the treatment of the lower urinary tract dysfunction in patients with multiple sclerosis?—A randomized study
- Author
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Glykas, I., Fragkoulis, Ch, Mitsikostas, D. D., Papatsoris, A., Mitsogiannis, I., Papadopoulos, G., Skolarikos, A., Gkialas, I., Ntoumas, K., and Dellis, A.
- Published
- 2021
- Full Text
- View/download PDF
26. Neutral and adaptive loci reveal fine‐scale population structure in Eleginops maclovinus from north Patagonia
- Author
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Cristian B. Canales‐Aguirre, Wesley A. Larson, Garrett J. McKinney, C. Eliza Claure, J. Dellis Rocha, Santiago G. Ceballos, María I. Cádiz, José M. Yáñez, and Daniel Gomez‐Uchida
- Subjects
fjords ,Notothenioidei ,Patagonian blennie ,protandrous hermaphrodite ,salinity cline ,SNPs ,Ecology ,QH540-549.5 - Abstract
Abstract Patagonia is an understudied area, especially when it comes to population genomic studies with relevance to fishery management. However, the dynamic and heterogeneous landscape in this area can harbor an important but cryptic genetic population structure. Once such information is revealed, it can be integrated into the management of infrequently investigated species. Eleginops maclovinus is a protandrous hermaphrodite species with economic importance for local communities that are currently managed as a single genetic unit. In this study, we sampled five locations distributed across a salinity cline from Northern Patagonia to investigate the genetic population structure of E. maclovinus. We used restriction site‐associated DNA (RAD) sequencing and outlier tests to obtain neutral and adaptive loci, using FST and GEA approaches. We identified a spatial pattern of structuration with gene flow and spatial selection by environmental association. Neutral and adaptive loci showed two and three genetic groups, respectively. The effective population sizes estimated ranged from 572 (Chepu) to 14,454 (Chaitén) and were influenced more by locality than by salinity cline. We found loci putatively associated with salinity suggesting that salinity may act as a selective driver in E. maclovinus populations. These results suggest a complex interaction between genetic drift, gene flow, and natural selection in this area. Our findings also suggest several evolutionary significant units in this area, and the information should be integrated into the management of this species. We discussed the significance of these results for fishery management and suggest future directions to improve our understanding of how E. maclovinus has adapted to the dynamic waters of Northern Patagonia.
- Published
- 2022
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27. Electrocaloric effect in Ba(0.2)Ca(0.8)Ti(0.95)Ge(0.05)O(3) determined by a new pyroelectric method
- Author
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Asbani, B., Dellis, J. -L., Gagou, Y., Kaddoussi, H., Lahmar, A., Amjoud, M., Mezzane, D., Kutnjak, Z., and Marssi, M. El
- Subjects
Condensed Matter - Materials Science - Abstract
The present letter explores the electrocaloric effect (ECE) in the lead free oxide Ba0.8Ca0.2Ti0.95Ge0.05O3 ceramics (BCTG). The electrocaloric responsivity (dT/dE) was determined by two different methods using the Maxwell relationship (dT/dE)~(dP/dT)_E. In a first well-known indirect method, P-E hysteresis loops were measured in a wide temperature range from which the pyroelectric coefficient p_E=(dP/dT)_E and thus (dT/dE) were determined by derivation of P(T,E) data. In the second novel method the pyroelectric coefficient p_E and consequently the electrocaloric responsivity was determined by direct measurements of the pyroelectric currents under different applied electric fields. Within the experimental error good agreement was obtained between two methods with an electrocaloric responsivity equal to 0.18 +/- 0.05 10-6 K.m.V-1 was obtained at about 410 K, Comment: 5 pages, 4 figures
- Published
- 2015
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28. Validity and reliability of the Greek version of the neurogenic bladder symptom score (NBSS) questionnaire in a sample of Greek patients with multiple sclerosis
- Author
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Tzelves, Lazaros, Glykas, Ioannis, Fragkoulis, Charalampos, Mitsikostas, Dimos-Dimitrios, Skolarikos, Andreas, Welk, Blayne, and Dellis, Athanasios
- Published
- 2021
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29. A-blockers for the management of lower urinary tract symptoms in patients with prostate cancer treated with external beam radiotherapy: a randomized controlled study
- Author
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Tsirkas, Kimon, Zygogianni, Anna, Kougioumtzopoulou, Andromachi, Kouloulias, Vasileios, Liakouli, Zoi, Papatsoris, Athanasios, Georgakopoulos, John, Antypas, Christos, Armpillia, Christina, and Dellis, Athanasios
- Published
- 2021
- Full Text
- View/download PDF
30. Perspectives on the urological care in Parkinson’s disease patients
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Mohamad Moussa, Mohamad Abou Chakra, Athanasios G. Papatsoris, Athanasios Dellis, Baraa Dabboucy, Michael Peyromaure, Nicolas Barry Delongchamps, Hugo Bailly, and Igor Duquesne
- Subjects
Parkinson’s disease ,Lower urinary tract dysfunction ,Neurogenic bladder ,Urology ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Parkinson's disease (PD) is recognized as the most common neurodegenerative disorder after Alzheimer's disease. Lower urinary tract symptoms are common in patients with PD, either storage symptoms (overactive bladder symptoms or OAB) or voiding symptoms. The most important diagnostic clues for urinary disturbances are provided by the patient's medical history. Urodynamic evaluation allows the determination of the underlying bladder disorder and may help in the treatment selection. Pharmacologic interventions especially anticholinergic medications are the first-line option for treating OAB in patients with PD. However, it is important to balance the therapeutic benefits of these drugs with their potential adverse effects. Intra-detrusor Botulinum toxin injections, electrical stimulation were also used to treat OAB in those patients with variable efficacy. Mirabegron is a β3-agonist that can also be used for OAB with superior tolerability to anticholinergics. Desmopressin is effective for the management of nocturnal polyuria which has been reported to be common in PD. Deep brain stimulation (DBS) surgery is effective in improving urinary functions in PD patients. Sexual dysfunction is also common in PD. Phosphodiesterase type 5 inhibitors are first-line therapies for PD-associated erectile dysfunction (ED). Treatment with apomorphine sublingually is another therapeutic option for PD patients with ED. Pathologic hypersexuality has occasionally been reported in patients with PD, linked to dopaminergic agonists. The first step of treatment of hypersexuality consists of reducing the dose of dopaminergic medication. This review summarizes the epidemiology, pathogenesis, risk factors, genetic, clinical manifestations, diagnostic test, and management of PD. Lastly, the urologic outcomes and therapies are reviewed.
- Published
- 2022
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31. Cancer Stem Cell and Aggressiveness Traits Are Promoted by Stable Endothelin-Converting Enzyme-1c in Glioblastoma Cells
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Ignacio Niechi, José I. Erices, Diego Carrillo-Beltrán, Atenea Uribe-Ojeda, Ángelo Torres, José Dellis Rocha, Daniel Uribe, María A. Toro, Karla Villalobos-Nova, Belén Gaete-Ramírez, Gabriel Mingo, Gareth I. Owen, Manuel Varas-Godoy, Lilian Jara, Francisco Aguayo, Verónica A. Burzio, Claudia Quezada-Monrás, and Julio C. Tapia
- Subjects
glioblastoma ,stemness ,endothelin ,CK2 ,aggressiveness ,Cytology ,QH573-671 - Abstract
Glioblastoma (GBM) is the most common and aggressive type of brain tumor due to its elevated recurrence following treatments. This is mainly mediated by a subpopulation of cells with stemness traits termed glioblastoma stem-like cells (GSCs), which are extremely resistant to anti-neoplastic drugs. Thus, an advancement in the understanding of the molecular processes underlying GSC occurrence should contribute significantly towards progress in reducing aggressiveness. High levels of endothelin-converting enzyme-1 (ECE1), key for endothelin-1 (ET-1) peptide activation, have been linked to the malignant progression of GBM. There are four known isoforms of ECE1 that activate ET-1, which only differ in their cytoplasmic N-terminal sequences. Isoform ECE1c is phosphorylated at Ser-18 and Ser-20 by protein kinase CK2, which increases its stability and hence promotes aggressiveness traits in colon cancer cells. In order to study whether ECE1c exerts a malignant effect in GBM, we designed an ECE1c mutant by switching a putative ubiquitination lysine proximal to the phospho-serines Lys-6-to-Arg (i.e., K6R). This ECE1cK6R mutant was stably expressed in U87MG, T98G, and U251 GBM cells, and their behavior was compared to either mock or wild-type ECE1c-expressing clone cells. ECE1cK6R behaved as a highly stable protein in all cell lines, and its expression promoted self-renewal and the enrichment of a stem-like population characterized by enhanced neurospheroid formation, as well as increased expression of stem-like surface markers. These ECE1cK6R-derived GSC-like cells also displayed enhanced resistance to the GBM-related chemotherapy drugs temozolomide and gemcitabine and increased expression of the ABCG2 efflux pump. In addition, ECE1cK6R cells displayed enhanced metastasis-associated traits, such as the modulation of adhesion and the enhancement of cell migration and invasion. In conclusion, the acquisition of a GSC-like phenotype, together with heightened chemoresistance and invasiveness traits, allows us to suggest phospho-ECE1c as a novel marker for poor prognosis as well as a potential therapeutic target for GBM.
- Published
- 2023
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32. Spin-noise correlations and spin-noise exchange driven by low-field spin-exchange collisions
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Dellis, A. T., Loulakis, M., and Kominis, I. K.
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Physics - Atomic Physics ,Condensed Matter - Mesoscale and Nanoscale Physics ,Mathematics - Probability ,Quantum Physics - Abstract
The physics of spin exchange collisions have fueled several discoveries in fundamental physics and numerous applications in medical imaging and nuclear magnetic resonance. We here report on the experimental observation and theoretical justification of spin-noise exchange, the transfer of spin-noise from one atomic species to another. The signature of spin-noise exchange is an increase of the total spin-noise power at low magnetic fields, on the order of 1 mG, where the two-species spin-noise resonances overlap. The underlying physical mechanism is the two-species spin-noise correlation induced by spin-exchange collisions., Comment: 7 pages, 5 figures
- Published
- 2013
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33. 2 SINGLE INTRASPHINCTERIC INJECTION OF AUTOLOGOUS ADIPOSE-DERIVED STEM CELLS TO TREAT STRESS URINARY INCONTINENCE AFTER RADICAL PROSTATECTOMY: A PILOT STUDY
- Author
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M Moussa, B Dabboucy, A Papatsoris, Y Moussa, Y Fares, A Dellis, H Issa, H Bailly, and M Abou Chakra
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Diseases of the genitourinary system. Urology ,RC870-923 - Published
- 2022
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- View/download PDF
34. Photon statistics as an experimental test discriminating between theories of spin-selective radical-ion-pair reactions
- Author
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Dellis, A. T. and Kominis, I. K.
- Subjects
Quantum Physics ,Physics - Biological Physics ,Physics - Chemical Physics - Abstract
Radical-ion-pair reactions were recently shown to represent a rich biophysical laboratory for the application of quantum measurement theory methods and concepts. We here propose a concrete experimental test that can clearly discriminate among the fundamental master equations currently attempting to describe the quantum dynamics of these reactions. The proposed measurement based on photon statistics of fluorescing radical pairs is shown to be model-independent and capable of elucidating the singlet-triplet decoherence inherent in the radical-ion-pair recombination process., Comment: 4 pages, 2 figures
- Published
- 2011
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35. Epitaxial growth and magnetoelectric relaxor behavior in multiferroic 0.8Pb(Fe1/2Nb1/2)O3-0.2Pb(Mg1/2W1/2)O3 thin films
- Author
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Peng, Wei, Lemée, N., Dellis, J. -L., Shvartsman, V. V., Borisov, P., Kleemann, W., Trontelj, Z., Holc, J., Kosec, M., Blinc, R., and Karkut, M. G.
- Subjects
Condensed Matter - Materials Science - Abstract
We present electric and magnetic properties of 0.8Pb(Fe1/2Nb1/2)O3-0.2Pb(Mg1/2W1/2)O3 films epitaxially grown on (001) SrTiO3 substrates using pulsed laser deposition. A narrow deposition window around 710 oC and 0.2 mbar has been identified to achieve epitaxial single-phase thin films. A typical Vogel-Fulcher relaxor-like dielectric and magnetic susceptibility dispersion is observed, suggesting magnetoelectric relaxor behavior in these films similar to the bulk. We determine a magnetic cluster freezing temperature of 36 K, while observing weak ferromagnetism via magnetic hysteresis loops up to 300 K., Comment: 12 pages, 4 figures
- Published
- 2009
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36. The Quantum Zeno Effect Immunizes the Avian Compass Against the Deleterious Effects of Exchange and Dipolar Interactions
- Author
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Dellis, A. T. and Kominis, I. K.
- Subjects
Quantum Physics ,Physics - Biological Physics - Abstract
Magnetic-sensitive radical-ion-pair reactions are understood to underlie the biochemical magnetic compass used by avian species for navigation. Recent experiments have provided growing evidence for the radical-ion-pair magnetoreception mechanism, while recent theoretical advances have unravelled the quantum nature of radical-ion-pair reactions, which were shown to manifest a host of quantum-information-science concepts and effects, like quantum measurement, quantum jumps and the quantum Zeno effect. We here show that the quantum Zeno effect provides for the robustness of the avian compass mechanism, and immunizes it's magnetic and angular sensitivity against the deleterious and molecule-specific exchange and dipolar interactions., Comment: 6 pages, 4 figures
- Published
- 2009
37. Quantum Measurement Theory Explains the Deuteration Effect in Radical-Ion-Pair Reactions
- Author
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Dellis, A. T. and Kominis, I. K.
- Subjects
Quantum Physics ,Physics - Biological Physics ,Physics - Chemical Physics ,Quantitative Biology - Biomolecules ,Quantitative Biology - Quantitative Methods - Abstract
It has been recently shown that radical-ion pairs and their reactions are a paradigm biological system manifesting non-trivial quantum effects, so far invisible due to the phenomenological description of radical-ion-pair reactions used until now. We here use the quantum-mechanically consistent master equation describing magnetic-sensitive radical-ion-pair reactions to explain experimental data [C. R. Timmel and K. B. Henbest, Phil. Trans. R. Soc. Lond. A {\bf 362}, 2573 (2004); C. T. Rodgers, S. A. Norman, K. B. Henbest, C. R. Timmel and P. J. Hore, J. Am. Chem. Soc. {\bf 129} 6746 (2007)] on the effect of deuteration on the reaction yields. Anomalous behavior of radical-ion-pair reactions after deuteration, i.e. data inconsistent with the predictions of the phenomenological theory used so far, has been observed since the 70's and has remained unexplained until now., Comment: 4 pages, 4 figures
- Published
- 2009
38. Oil Film Thickness Measurements Combined with High Temperature Friction Investigations in a Simplified Piston-Ring Lubrication Test Rig
- Author
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P.S. Dellis
- Subjects
piston-ring lubrication ,single-ring test rig ,oil film thickness ,friction force measurements ,capacitance ,cavitation ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
The effect of lubricants properties in oil film thickness was evaluated and linked to performance limitations in view of cavitation appearance, its initia Ccapacitance tion and development. The piston-ring and the cylinder liner interface are characterized in terms of oil film thickness measurements. Study of cavitation in lubricants and its rheology were presented in previous studies and results of different lubricants, speed, load, temperature and piston-ring curvatures were assessed to achieve useful tribological engine data that apply to the piston-cylinder assembly. The evaluation of new designs that can be applied to the ring/liner interface and many future parametric studies that can be combined with surface modifications in both parts of the assembly are under examination. The use of a simplified single-ring test rig that utilizes a steady piston-ring section of overall width 5 mm placed under a flat liner surface that reciprocates instead, takes advantage of significantly less uncertainties when compared to engine experiments. Minimum oil film thickness measurements (MOFT) is studied for different lubricants as a variation of temperature and simultaneously friction high temperature results for the whole stroke length are presented. Measurement transducers for the separation of the metal surfaces (liner and piston-ring) and the friction force developed in the contact surfaces were the conventional methods used. Within certain parts of the stroke where friction reaches its maximum value, a greater focus is given to evaluate the effect of different operating conditions. Useful conclusions are drawn regarding lubricants behavior under cavitation that can be used to new additives design and enhancement of lubricant physical-chemical properties that have the potential to conform to the even stricter emission regulations that will apply in the future.
- Published
- 2019
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39. TEMPERATURE EFFECT IN MINIMUM OIL FILM THICKNESS MEASUREMENTS IN A SIMPLIFIED SINGLE-RING TEST RIG USED TO SIMULATE THE PISTON-CYLINDER ASSEMBLY
- Author
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Polychronis S. DELLIS
- Subjects
piston-ring ,single-ring test rig ,oil film ,friction ,capacitance ,cavitation ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
As part of the study of the complex lubrication phenomena between the piston-ring and the cylinder liner, it is important to characterize the oil film thickness in view of new designs that can be implemented for the piston-ring assembly. In previous studies parametric results of different lubricants, speed, load, temperature and piston-ring surface were presented to complement on the cavitation rheological phenomena (initiation and development) and to interpret the effect of physical-chemical properties of the lubricants in oil film thickness, friction and oil film pressure. Measurements were conducted in a simplified single-ring test rig, where a steady piston-ring section of overall width 5 mm is placed under a flat surface used as a reciprocating liner, taking advantage of significantly less uncertainties when compared to engine experiments. The advantage of this layout is that it can provide abundance of results that in turn, are being simultaneously interpreted in an easier and safer way prior to engine implementation and testing. In this manner, the effect of different operating conditions is assessed to achieve solid experimental results, useful in engine tribological applications in the piston-cylinder assembly, that comply with the emission regulations of today and the near future. This presentation is focused on the effect of temperature in minimum oil film thickness measurements (MOFT) for different lubricants. An electrical method is used in this set of experiments to measure the oil film thickness (capacitance). The testing is applied for different speeds and loads so that a complete picture of the lubricants behavior can be taken and, in parallel, friction measurements are presented to assess the MOFT results for specific parts of the stroke. The results show the effect of different lubricant properties in MOFT and give an insight of the conditions of cavitation occurrence at the early parts of the stroke as temperature rises. Further processing of these results provides very useful conclusions and the combination of the lubricants behavior under cavitating conditions, can lead to innovative additives design-formulation and new lubricant properties.
- Published
- 2019
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40. The Automated Spectrometric Oil Analysis Decision Taking Procedure as a Tool to Prevent Aircraft Engine Failures
- Author
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P.S. Dellis
- Subjects
Spectrometric oil analysis ,Reciprocating piston engines ,Turbine engines ,Wear metals ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
The purpose of spectrometric oil analysis is: – To diagnose imminent wear inside engine assemblies so that possible failures can be avoided, – To forecast and evaluate acquired data statistics regarding the operation of engine assemblies under known climate and operational conditions. Apart from the above mentioned double aim of the lubricant analysis laboratory, its importance is established from the extent of these measurements from the Air Force, where they were initially implemented, to the Navy and the Army and customers with large fleets. The present work presents spectrometric oil analysis as a diagnostic maintenance tool, it refers to the evaluation methodology and criteria of spectrometric oil analysis that come from aeronautical equipment (as it applies to the Hellenic Air Force), it describes the operation of a database used for the derivation of automated decision taking codes according to specific criteria described in US NAVAIR technical manual and highlights the importance of this procedure to preventing failure in reciprocating piston and turbine aircraft engines. Selected data from the spectrometer are also presented to point out the importance of the methodology in failure prevention as it applies in reciprocating internal combustion engines, a helicopter gearbox and a turboprop engine.
- Published
- 2019
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- View/download PDF
41. Bias field effect on the temperature anomalies of dielectric permittivity in PbMg1/3Nb2/3O3- PbTiO3 single crystals
- Author
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Raevski, I. P., Prosandeev, S. A., Emelyanov, A. S., Raevskaya, S. I., Colla, Eugene V., Viehland, D., Kleemann, W., Vakhrushev, S. B., Dellis, J-L., Marssi, M. El, and Jastrabik, L.
- Subjects
Condensed Matter - Materials Science - Abstract
In contrast to ordinary ferroelectrics where the temperature, Tm, of the permittivity maximum monotonically increases with bias field, E, in (1-x)PbMg1/3Nb2/3O3-(x)PbTiO3 (0
- Published
- 2005
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42. Nontrivial dependence of dielectric stiffness and SHG on dc bias in relaxors and dipole glasses
- Author
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Prosandeev, S. A., Raevski, I. P., Emelyanov, A. S., Colla, Eugene V., Dellis, J-L., Marssi, M. El, Kapphan, S. P., and Jastrabik, L.
- Subjects
Condensed Matter - Materials Science - Abstract
Dielectric permittivity and Second Harmonic Generation (SHG) studies in the field-cooled mode show a linear dependence of dielectric stiffness (inverse dielectric permittivity) on dc bias in PMN-PT crystals and SHG intensity in KTaO$_{3}$:Li at small Li concentrations. We explain this unusual result in the framework of a theory of transverse, hydrodynamic-type, instability of local polarization., Comment: 5 figures
- Published
- 2004
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- View/download PDF
43. Does Party Polarization Affect the Electoral Prospects of a New Centrist Candidate?
- Author
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Arnaud Dellis
- Subjects
polarization ,strategic voting ,centrist candidate ,plurality voting ,laboratory experiment ,Technology ,Social Sciences - Abstract
Does party polarization affect the electoral prospects of a new centrist candidate? The paper investigates this question in the context of a laboratory experiment where a centrist candidate is added to the race between a left candidate and a right candidate. The experimental design varies the polarization of the left and right candidates. The paper focuses on the effect of party polarization on the electoral prospects of a new centrist candidate through strategic voting behavior with experimental subjects acting as voters. The paper yields two main results: (1) party polarization initially improves the electoral prospects of a new centrist candidate; and (2) the effect of party polarization on the electoral prospects of the centrist weakens and ultimately disappears as elections are repeated. This happens because party polarization slows down the speed at which voters desert their candidate and vote strategically for the centrist in an apparent attempt at preventing the election of the candidate on the opposite side.
- Published
- 2022
- Full Text
- View/download PDF
44. PSMA-based therapeutics for prostate cancer
- Author
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Stamatakos, Panagiotis Velissarios, Fragkoulis, Charalampos, Leventi, Aggeliki, Gklinos, Konstantinos, Kontolatis, Nikolaos, Papatsoris, Athanasios, and Dellis, Athanasios
- Abstract
ABSTRACTIntroductionThe prostate cancer (PCa) consists the most frequently diagnosed malignancy of urogenital system in males. Traditionally, treatment of localized PCa was based on surgery or radiotherapy while hormonotherapy was used in more advanced stages. However, the implementation of radiolabels has revolutionized the landscape of prostate cancer. Specifically, prostate-specific membrane antigen (PSMA) has been investigated in different aspects of PCa therapeutic era.Areas coveredA literature review is presented about the implications of PSMA radiolabels on prostate cancer treatment. PSMA tracers were initially used as an imaging technique. Afterwards, PSMA labeled with isotopes presenting cytotoxic abilities, such as lutetium-117 and actinium-225, while reports exist about the use of radioligand immunotherapy. Meanwhile, ongoing trials examine the development of novel radionuclides as well as the evolution of the PSMA-targeted ligands.Expert opinionCurrently, PSMA radioligand treatment of prostate cancer is approved in the metastatic stage of the disease. Meanwhile, a variety of trials exist about its possible role in less advanced stages. However, plenty of parameters should be addressed before these implementations, such as PSMA dosage, dosimetry issues, and its safety profile. A future well-designed study with proper patient selection is mandatory to further explore PSMA radioligand theranostics perspectives.
- Published
- 2024
- Full Text
- View/download PDF
45. Nocebo-Prone Behavior Associated with SARS-CoV-2 Vaccine Hesitancy in Healthcare Workers
- Author
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Dimos D. Mitsikostas, Konstantina Aravantinou-Fatorou, Christina Deligianni, Evrydiki Kravvariti, Eleni Korompoki, Maria Mylona, Pinelopi Vryttia, Georgia Papagiannopoulou, Eumorphia-Maria Delicha, Athanasios Dellis, Georgios Tsivgoulis, Meletios A. Dimopoulos, Martina Amanzio, and Petros P. Sfikakis
- Subjects
SARS-CoV-2 ,nocebo ,vaccine hesitancy ,healthcare workers ,tolerability ,adverse event ,Medicine - Abstract
Among healthcare workers (HCWs), SARS-CoV-2 vaccine hesitancy may be linked to a higher susceptibility to nocebo effects, i.e., adverse events (AEs) experienced after medical treatments due to negative expectations. To investigate this hypothesis a cross-sectional survey was performed with a self-completed questionnaire that included a tool (Q-No) for the identification of nocebo-prone individuals. A total of 1309 HCWs (67.2% women; 43.4% physicians; 28.4% nurses; 11.5% administrative staff; 16.6% other personnel) completed the questionnaires, among whom 237 (18.1%) had declined vaccination. Q-No scores were ≥15 in 325 participants (24.8%) suggesting nocebo-prone behavior. In a multivariate logistic regression model with Q-No score, age, gender, and occupation as independent variables, estimated odds ratios (ORs) of vaccination were 0.43 (i.e., less likely, p < 0.001) in participants with Q-No score ≥ 15 vs. Q-No score < 15, 0.58 in females vs. males (p = 0.013), and 4.7 (i.e., more likely) in physicians vs. other HCWs (p < 0.001), independent of age, which was not significantly associated with OR of vaccination. At least one adverse effect (AE) was reported by 67.5% of vaccinees, mostly local pain and flu-like symptoms. In a multivariate logistic regression model, with Q-No score, age, gender, and occupation as independent variables, estimated ORs of AE reporting were 2.0 in females vs. males (p < 0.001) and 1.47 in physicians vs. other HCWs (p = 0.017) independently of age and Q-No score, which were not significantly associated with OR of AE. These findings suggest that nocebo-prone behavior in HCWs is associated with SARS-CoV-2 vaccination hesitancy indicating a potential benefit of a campaign focused on nocebo-prone people.
- Published
- 2021
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- View/download PDF
46. Arterial irrigation of the head and neck of the pampas deer (Ozotoceros bezoarticus, Linnaeus 1758)
- Author
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Vazquez, Noelia, dos Santos, Dellis, and Pérez, William
- Published
- 2018
- Full Text
- View/download PDF
47. Aspects of Lubrication in a Reciprocating Single-ring Test Rig and Further Implementation to Engine Applications
- Author
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P.S. Dellis
- Subjects
Piston-ring lubrication ,Single-ring test rig ,Engine experiments ,Oil film ,Friction and pressure measurements ,Visualisation ,Cavitation ,Laser induced fluorescence ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
A major concern in modern engine design is the issue of the lubrication regime at the piston-liner assembly. To fully understand the complex lubrication phenomena between the piston-rings and cylinder liner in reciprocating engines and at the same time achieve minimal energy losses with the oncoming emission regulations, it is important to characterize the developing oil film. This dynamic process involves many factors, such as piston-ring and piston dynamics, starved lubrication, liner geometry deformation, lubricant - additive degradation and blow-by, which, in turn, enhance the difficulty of interpreting engine experimental results. The simplified test rig is used as a platform to develop oil film measuring techniques and study experimental results from different sensors by means of a robust and solid technique without the engine testing ambiguities, at different lubrication regimes. This paper is focused on experimental findings from the simplified test rig and how these can be applied on specially modified engines, with the respective sensors fitted. A comparison between the single-ring test rig and the engine visualization results is attempted so that similar forms of cavitation identified, be further studied. Moreover, a calibration coefficient for LIF engine experiments can be derived via the simplified test rig arrangement.
- Published
- 2017
48. Identification of potentially harmful bacterial genera of veterinary relevance in the Llanquihue urban wetlands.
- Author
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Dellis Rocha, José, Opitz, Catherine, Cárdenas, Vicente, Mella, Cristal, and Medina, Daniel A.
- Subjects
MICROCYSTIS ,MICROCYSTINS ,WETLANDS ,AGRICULTURE ,AQUATIC ecology ,AQUATIC biology ,ENVIRONMENTAL chemistry ,MICROBIAL ecology ,ENVIRONMENTAL research ,WETLAND soils - Published
- 2024
- Full Text
- View/download PDF
49. Phénotype allergologique des patients souffrant d’œsophagite à éosinophile avec un Food-Induced Immediate Response in the œsophagus syndrome
- Author
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Bohbot, L., primary, Dellis, P., additional, Hurson, C., additional, Thiebaut, M., additional, Piotin, A., additional, Lacroix, D., additional, Rebeuh, J., additional, Meyer, P., additional, De Blay, F., additional, and Metz-Favre, C., additional
- Published
- 2023
- Full Text
- View/download PDF
50. Using physics-based pose predictions and free energy perturbation calculations to predict binding poses and relative binding affinities for FXR ligands in the D3R Grand Challenge 2
- Author
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Athanasiou, Christina, Vasilakaki, Sofia, Dellis, Dimitris, and Cournia, Zoe
- Published
- 2017
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