cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Probing the Black Hole Metric. I. Black Hole Shadows and Binary Black-Hole Inspirals
Creators: name: Psaltis, Dimitrios
name: Talbot, Colm
name: Payne, Ethan
name: Mandel, Ilya
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: In General Relativity, the spacetimes of black holes have three fundamental properties: (i) they are the same, to lowest order in spin, as the metrics of stellar objects; (ii) they are independent of mass, when expressed in geometric units; and (iii) they are described by the Kerr metric. In this paper, we quantify the upper bounds on potential black-hole metric deviations imposed by observations of black-hole shadows and of binary black-hole inspirals in order to explore the current experimental limits on possible violations of the last two predictions. We find that both types of experiments provide correlated constraints on deviation parameters that are primarily in the tt-components of the spacetimes, when expressed in areal coordinates. We conclude that, currently, there is no evidence for a deviations from the Kerr metric across the 8 orders of magnitudes in masses and 16 orders in curvatures spanned by the two types of black holes. Moreover, because of the particular masses of black holes in the current sample of gravitational-wave sources, the correlations imposed by the two experiments are aligned and of similar magnitudes when expressed in terms of the far field, post-Newtonian predictions of the metrics. If a future coalescing black-hole binary with two low-mass (e.g., ~3 Msun) components is discovered, the degeneracy between the deviation parameters can be broken by combining the inspiral constraints with those from the black-hole shadow measurements.
description: Physical Review D, submitted
Spitzer Space Telescope observations of magnetic cataclysmic variables: possibilities for the presence of dust in polars
Creators: name: Brinkworth, C. S.
name: Hoard, D. W.
name: Wachter, S.
name: Howell, S. B.
name: Ciardi, D. R.
name: Szkody, P.
name: Harrison, T. E.
name: van Belle, G. T.
name: Esin, A. A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present Spitzer Space Telescope photometry of six short-period polars, EF Eri, V347 Pav, VV Pup, V834 Cen, GG Leo, and MR Ser. We have combined the Spitzer Infrared Array Camera (3.6 -8.0 microns) data with the 2MASS J, H, K_s photometry to construct the spectral energy distributions of these systems from the near- to mid-IR (1.235 - 8 microns). We find that five out of the six polars have flux densities in the mid-IR that are substantially in excess of the values expected from the stellar components alone. We have modeled the observed SEDs with a combination of contributions from the white dwarf, secondary star, and either cyclotron emission or a cool, circumbinary dust disk to fill in the long-wavelength excess. We find that a circumbinary dust disk is the most likely cause of the 8 micron excess in all cases, but we have been unable to rule out the specific (but unlikely) case of completely optically thin cyclotron emission as the source of the observed 8 micron flux density. While both model components can generate enough flux at 8 microns, neither dust nor cyclotron emission alone can match the excess above the stellar components at all wavelengths. A model combining both cyclotron and dust contributions, possibly with some accretion-generated flux in the near-IR, is probably required, but our observed SEDs are not sufficiently well-sampled to constrain such a complicated model. If the 8 micron flux density is caused by the presence of a circumbinary dust disk, then our estimates of the masses of these disks are many orders of magnitude below the mass required to affect CV evolution.
description: 58 pages, 14 figures, ApJ accepted
Αξιοποίηση Τεχνολογιών Web2.0 Για Τις Μαθησιακές Δυσκολίες:
Creators: name: Κατσαμάκη, Φανή Σταύρου
Publisher: name: Aristotle University of Thessaloniki
Year: 2010
Subjects: Web2.0
Wiki
Μαθησιακές Δυσκολίες
Learning Disabilities

description: Αντικείμενο της παρούσας εργασίας είναι η διερεύνηση των τρόπων αξιοποίησης των τεχνολογιών web2.0 για τις Μαθησιακές Δυσκολίες, ένα θέμα που απασχολεί έντονα τόσο την επιστημονική κοινότητα, όσο και τους ανθρώπους που εμπλέκονται σε αυτό. Θα εξεταστεί το κατά πόσο ένα σχετικά νέο και δημοφιλές εργαλείο web2.0, το wiki, μπορεί να συνεισφέρει στην αντιμετώπιση των μαθησιακών προβλημάτων. Ένα wiki θα δημιουργηθεί στην πράξη και θα δοκιμαστεί από χρήστες. Θα αναρτηθεί υλικό και θα παρατηρηθεί η αλληλεπίδραση μεταξύ των χρηστών και τα συμπεράσματα που θα προκύψουν. Επίσης, θα γίνει μια προσπάθεια δημιουργίας ενός ενδεικτικού εργαλείου διάγνωσης Μαθησιακών Δυσκολιών, που θα ενσωματωθεί στο wiki. Τέλος, θα αναφερθούν όλα τα αποτελέσματα των παραπάνω, καθώς επίσης οι προσδοκίες και οι προοπτικές των εφαρμογών που δημιουργήθηκαν στα πλαίσια αυτής της εργασίας.
description: The purpose of this dissertation is exploring the utilization of web2.0 technologies in Learning Disabilities. Lately, Learning Disabilities vividly occupy the research community, as well as the people concerned. A relatively new and popular web2.0 tool, the wiki, is going to be used in order to support learning problems. A real wiki is going to be created and users are going to participate. Data will be loaded on the wiki and the interactions between the users will be observed. In addition, an experimental diagnosis test for learning disabilities will be built and embedded into the wiki. Finally, there will be a reference to the results of the above mentioned and also to the expectations and the perspectives of all the applications created.
Medical Imaging and Computational Image Analysis in COVID-19 Diagnosis: A Review
Creators: name: Nabavi, Shahabedin
name: Ejmalian, Azar
name: Moghaddam, Mohsen Ebrahimi
name: Abin, Ahmad Ali
name: Frangi, Alejandro F.
name: Mohammadi, Mohammad
name: Rad, Hamidreza Saligheh
Publisher: name: arXiv
Year: 2020
Subjects: subject: Image and Video Processing (eess.IV)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Coronavirus disease (COVID-19) is an infectious disease caused by a newly discovered coronavirus. The disease presents with symptoms such as shortness of breath, fever, dry cough, and chronic fatigue, amongst others. Sometimes the symptoms of the disease increase so much they lead to the death of the patients. The disease may be asymptomatic in some patients in the early stages, which can lead to increased transmission of the disease to others. Many studies have tried to use medical imaging for early diagnosis of COVID-19. This study attempts to review papers on automatic methods for medical image analysis and diagnosis of COVID-19. For this purpose, PubMed, Google Scholar, arXiv and medRxiv were searched to find related studies by the end of April 2020, and the essential points of the collected studies were summarised. The contribution of this study is four-fold: 1) to use as a tutorial of the field for both clinicians and technologists, 2) to comprehensively review the characteristics of COVID-19 as presented in medical images, 3) to examine automated artificial intelligence-based approaches for COVID-19 diagnosis based on the accuracy and the method used, 4) to express the research limitations in this field and the methods used to overcome them. COVID-19 reveals signs in medical images can be used for early diagnosis of the disease even in asymptomatic patients. Using automated machine learning-based methods can diagnose the disease with high accuracy from medical images and reduce time, cost and error of diagnostic procedure. It is recommended to collect bulk imaging data from patients in the shortest possible time to improve the performance of COVID-19 automated diagnostic methods.
description: 29 pages, 4 tables
Brucellosis in main livestock species in urban areas of Morogoro, Tanzania
Creators: name: Coletha  Mathew
name: V. K.  Agusta
name: W. G. Mitao
name: R.R.  Kazwala
Publisher: name: AAS Open Research
Year: 2019

description: Background: Brucellosis is an important disease worlwide affecting animals and people. Tanzania has selected brucellosis among six important diseases to be controlled. Yet, its status in livestock in some parts of the country is unknown.
Objectives: The aim of the present study was to evaluate the status of brucellosis and risk factors in main livestock that are kept in herds with more than one type of domestic animals.
Methodology: A cross-sectional study design with 277 serum samples from pigs, cattle and small-ruminants, from six wards were analysed using Rose Bengal Test. Serum from pigs were also parallel analyzed using Buffered Plate Agglutination test. Structured questionnaire and direct observation were used to collect risk factors.
Results: The present results indicate that animals tested have no Brucella infection. Contact of animals from different herds, lack of screening newly acquired animals, movement of breeding bulls between farms, improper disposal of abortion materials, pooled milk for calves, and absence of calving pens were risk factors observed.
Conclusion: Brucella infections was not apparent in the study area although the risk factors were present highlighting that the situation might change. Continuous monitoring of the disease in the area and setting clear strategy for control of the disease using interdisciplinary approach is recommended.
Physiology of Cynoglossum officinale seed dormancy and germination
Creators: name: Stabell, Elisa Ulrika
Publisher: name: University of British Columbia
Year: 2009

description: The role of the seed coat in inhibiting seed germination of Cynoglossum officinale, a rangeland weed in British Columbia, was studied. Pricking, acid and mechanical scarification increased germination significantly. These treatments increased O₂ uptake only slightly, with the exception of an initial burst in O₂ uptake by seeds mechanically scarified for 6 h. The results suggest that only a small percent of the six-fold increase in O₂ uptake following decoating, reported in an earlier study, is necessary for seed germination. Germination of seeds incubated at a high O₂ level was greater than that of seeds incubated in air, and O₂ uptake by seeds in O₂-saturated water was 150% higher than for seeds in air-saturated water. O₂ consumption by the seed coat was not a major factor in limiting O₂ availability to the embryo in the intact seed. These results taken together suggest that C. officinale seed coat regulates germination by restricting O₂ diffusion. The seed coat may also inhibit germination by mechanically restricting embryo expansion. The methanol-insoluble phenolics constitute <1% of the total phenolic pool in the embryo. Potential oxidation of methanol-insoluble phenolics can only account for a small percentage of the large increase in O₂ uptake following decoating. The relationship between seed phenolics and appearance of seed coat-imposed dormancy during seed development was studied. During the later maturation stages, the O₂ uptake by intact, and decoated seeds declined, with a larger decrease in intact seeds. In the most mature seeds there was a three-fold increase in O₂ uptake after decoating. Decoating also increased germination from 0% to 100%. As the seeds maturated, the methanol-soluble phenolic content of the embryo remained stable but that of the seed coat declined. This decline was associated with a large increase in thioglycolic acid-soluble phenolics, presumably lignin, in the seed coat. The results suggest that during later seed maturation stages, methanol-soluble phenolics in the seed coat are polymerized to lignin. The lignin may contribute to the formation of an O₂-impermeable and mechanically hard seed coat, which in turn may render the seed dormant.
Pairing properties of superheavy nuclei
Creators: name: Staszczak, A.
name: Dobaczewski, J.
name: Nazarewicz, W.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Pairing properties of even-even superheavy N=184 isotones are studied within the Skyrme-Hartree-Fock+BCS approach. In the particle-hole channel we take the Skyrme energy density functional SLy4, while in the particle-particle channel we employ the seniority pairing force and zero-range delta-interactions with different forms of density dependence. We conclude that the calculated static fission trajectories weakly depend on the specific form of the delta-pairing interaction. We also investigate the impact of triaxiality on the inner fission barrier and find a rather strong Z dependence of the effect.
description: 9 pages, 5 figures, submitted to International Journal of Modern Physics E
Asymmetric Coupling in Two-Channel Simple Exclusion Processes
Creators: name: Pronina, Ekaterina
name: Kolomeisky, Anatoly B.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Simple exclusion processes for particles moving along two parallel lattices and jumping between them are theoretically investigated for asymmetric rates of transition between the channels. An approximate theoretical approach, that describes the particle dynamics exactly in any vertical cluster of two parallel sites and neglects the correlations between the different vertical clusters, is applied to calculate stationary-state density profiles, currents and phase diagrams. Surprisingly, it is found that asymmetry in the coupling between the channels leads to a very complex phase behavior that is very different from two-channel simple exclusion processes with symmetric coupling. There are seven stationary-state phases in the simple exclusion processes with asymmetric transition rates between the channels, in contrast to three phases found for the systems with symmetric coupling. In addition, a new maximal-current phase with a domain wall in the middle of the lattices, that has no analogs in other exclusion processes, is observed. Although the explicit calculations are presented only for the case of full asymmetry, when the particles can only jump between the channels in one direction, the properties of two-channel simple exclusion systems with general asymmetry are also discussed. Theoretical predictions are in excellent agreement with extensive computer Monte Carlo simulations.
description: 12 pages, 6 figures
On the Nature of the Unique H$α$-Emitting T Dwarf 2MASS J12373919+6526148
Creators: name: Liebert, James
name: Burgasser, Adam J.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We explore and discount the hypothesis that the strong, continual H$α$-emitting T dwarf 2MASS J12373919+6526148 can be explained as a young, low gravity, very low mass brown dwarf. The source is already known to have a marginally-fainter absolute magnitude than similar T dwarfs with trigonometric parallax measurements, and has a tangential velocity consistent with old disk kinematics. Applying the technique of Burgasser, Burrows & Kirkpatrick on new near infrared spectroscopy for this source, estimates of its {\teff}, $\log{g}$ and metallicity ([M/H]) are obtained. 2M 1237+6526 has a {\teff} $\approx$ 800-850 K. If [M/H] is solar, $\log{g}$ is as high as $\sim$5.5 (cgs) and this source is older than 10 Gyr. We find a more plausible scenario to be a modestly subsolar metallicity ([M/H] = -0.2) and moderate $\log{g}$ $\sim$ 5.0, implying an age older than 2 Gyr and a mass greater than 0.035 M$_{\sun}$. The alternative explanation of the unique emission of this source, involving an interacting, close, double degenerate system, should be investigated further. Indeed, there is some evidence of a {\teff} $
description: Astrophysical Journal, in press 15 pages, 5 figures
The Dirac propagator in the Kerr-Newman metric
Creators: name: Batic, D.
name: Schmid, H.
Publisher: name: arXiv
Year: 2006
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We give an alternative proof of the completeness of the Chandrasekhar ansatz for the Dirac equation in the Kerr-Newman metric. Based on this, we derive an integral representation for smooth compactly supported functions which in turn we use to derive an integral representation for the propagator of solutions of the Cauchy problem with initial data in the above class of functions. As a by-product, we also obtain the propagator for the Dirac equation in the Minkowski space-time in oblate spheroidal coordinates.
description: 29 pages, modifications in the abstract and in the introduction, small improvements in section 2.1
Συγκριτική μελέτη και διερεύνηση αλγορίθμων αυτοπροσαρμοζόμενης διαφορικής εξέλιξης:
Creators: name: Αντωνιάδης, Κωνσταντίνος Γεωργίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2010
Subjects: Αλγόριθμος
Εξελικτικοί αλγόριθμοι
Διαφορική εξέλιξη
Algorithm
Evolution algorithms
Differential evolution

description: στην παρούσα εργασία μελετήθηκε η συμπεριφορά του αλγορίθμου διαφορικής εξέλιξης (αδε). ο αδε αποτελεί ένα χρήσιμο εργαλείο όσον αφορά την βελτιστοποίηση συναρτήσεων και έχει ως τώρα χρησιμοποιηθεί σε πολλές πρακτικές εφαρμογές. ο αλγόριθμος αυτός παρουσιάζει το πλεονέκτημα ότι έχει μόνο λίγες παραμέτρους που πρέπει να οριστούν από τον χρήστη. παρόλα αυτά η ρύθμιση των παραμέτρων αυτών δεν είναι εύκολη υπόθεση. στην εργασία αυτή παρουσιάζεται ένας νέος αλγόριθμος, ο αλγόριθμος αυτοπροσαρμοζόμενης διαφορικής εξέλιξης, όπου οι παράμετροι πλέον δεν ορίζονται από τον χρήστη αλλά ο καθορισμός τους είναι μέρος της λειτουργίας του αλγορίθμου. οι παραλλαγές αυτές, διευκολύνουν την χρήση του αλγορίθμου βελτιστοποίησης, μειώνοντας τις μεταβλητές ελέγχου, κάνοντας έτσι τους αλγόριθμους πιο προσιτούς και σε μη εξειδικευμένους χρήστες.
description: this paper studied the behavior of the differential evolution (de). the de is a useful tool for optimizing functions, and has so far used in many practical applications. this algorithm has the advantage that it is only a few parameters must be defined by the user. however, the regulation of these parameters is not always an easy case. in this work a new algorithm, the self adaptive differential evolution, is presented, where the parameters are no longer defined by the user, but the setting is part of the operation of the algorithm. these variants, facilitating the use of algorithm optimization, reducing the control variables, making the algorithms more accessible to non-expert users.
Large angle precession of magnetization maintained by a microwave voltage
Creators: name: Imamura, Hiroshi
name: Matsumoto, Rie
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Effects of a microwave voltage on magnetization precession are analyzed based on a macrospin model. The microwave voltage induces the oscillating anisotropy field through the voltage controlled magnetic anisotropy (VCMA) effect, and then stimulates the magnetization. The large angle precession is maintained if the magnetization synchronizes with the microwave voltage. The effective equations of motion of the magnetization with an oscillating anisotropy field are derived, and the mechanism of the synchronization is clarified by analyzing the derived equations of motion. The conditions of the angular frequency detuning and the amplitude of the oscillating anisotropy field for synchronization are obtained. The results are useful for development of the VCMA-based energy-efficient spintronics devices using magnetization precession such as a VCMA-based magnetoresistive random access memory and a nano-scale microwave magnetic field generator.
description: 7 pages, 5 figures
A Threat Modelling Approach to Analyze and Mitigate Botnet Attacks in Smart Home Use Case
Creators: name: Abbas, Syed Ghazanfar
name: Zahid, Shahzaib
name: Hussain, Faisal
name: Shah, Ghalib A.
name: Husnain, Muhammad
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cryptography and Security (cs.CR)
subject: Computers and Society (cs.CY)
subject: FOS: Computer and information sciences

description: Despite the surging development and utilization of IoT devices, the security of IoT devices is still in infancy. The security pitfalls of IoT devices have made it easy for hackers to take over IoT devices and use them for malicious activities like botnet attacks. With the rampant emergence of IoT devices, botnet attacks are surging. The botnet attacks are not only catastrophic for IoT device users but also for the rest of the world. Therefore, there is a crucial need to identify and mitigate the possible threats in IoT devices during the design phase. Threat modelling is a technique that is used to identify the threats in the earlier stages of the system design activity. In this paper, we propose a threat modelling approach to analyze and mitigate the botnet attacks in an IoT smart home use case. The proposed methodology identifies the development-level and application-level threats in smart home use case using STRIDE and VAST threat modelling methods. Moreover, we reticulate the identified threats with botnet attacks. Finally, we propose the mitigation techniques for all identified threats including the botnet threats.
description: Accepted in IEEE TrustCom 2020, 7 Pages, 4 Figures, 3 Tables
Connecting the generalized robustness and the geometric measure of entanglement
Creators: name: Cavalcanti, Daniel
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The main goal of this paper is to provide a connection between the generalized robustness of entanglement ($R_g$) and the geometric measure of entanglement ($E_{GME}$). First, we show that the generalized robustness is always higher than or equal to the geometric measure. Then we find a tighter lower bound to $R_g(ρ)$ based only on the purity of $ρ$ and its maximal overlap to a separable state. As we will see it is also possible to express this lower bound in terms of $E_{GME}$.
description: 4 pages, 2 figures. Comments welcome. v2: text improved - some completely symmetric states were used to illustrate the results. Comments are always welcome! v3: minor changes. Accepted by Phys. Rev. A. v4: results on symmetric states fixed
Study on charmonium(-like) mesons within a diabatic approach
Creators: name: Zhang, Zi-Zhao
name: Li, Rong
name: Liu, Bo-Chao
Publisher: name: arXiv
Year: 2025
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In this work, we study the charmonium(-like) spectrum below 4.1 GeV using the diabatic approach, which offers a unified description of conventional and unconventional heavy meson states. Compared to previous studies, we consider a more realistic $c\bar c$ potential with including the spin-dependent interactions, which allows us to obtain more states and get more insights on the charmonium spectrum. Based on our calculation, we obtain the masses of the charmonium spectrum which align with the experimental data well. We also present the probabilities of finding various components, i.e. $c\bar c$ or meson-meson pair, in those states. Our results support the arguments that the $χ_{c1}(3872)$, $ψ(4040)$ and $χ_{c2}(3930)$ have significant molecular components. In addition, our calculations show that the $χ_{c0}(3860)$ and $ψ(3770)$ can be looked as the candidates for the charmonium states $χ_{c0}(2P)$ and $ψ(1D)$, respectively.
description: 9 pages, 5 figures
Gamma rays from colliding winds of massive stars
Creators: name: Reimer, Anita
name: Reimer, Olaf
name: Pohl, Martin
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Colliding winds of massive binaries have long been considered as potential sites of non-thermal high-energy photon production. This is motivated by the detection of non-thermal spectra in the radio band, as well as by correlation studies of yet unidentified EGRET gamma-ray sources with source populations appearing in star formation regions. This work re-considers the basic radiative processes and its properties that lead to high energy photon production in long-period massive star systems. We show that Klein-Nishina effects as well as the anisotropic nature of the inverse Compton scattering, the dominating leptonic emission process, likely yield spectral and variability signatures in the gamma-ray domain at or above the sensitivity of current or upcoming gamma ray instruments like GLAST-LAT. In addition to all relevant radiative losses, we include propagation (such as convection in the stellar wind) as well as photon absorption effects, which a priori can not be neglected. The calculations are applied to WR140 and WR147, and predictions for their detectability in the gamma-ray regime are provided. Physically similar specimen of their kind like WR146, WR137, WR138, WR112 and WR125 may be regarded as candidate sources at GeV energies for near-future gamma-ray experiments. Finally, we discuss several aspects relevant for eventually identifying this source class as a gamma-ray emitting population. Thereby we utilize our findings on the expected radiative behavior of typical colliding wind binaries in the gamma-ray regime as well as its expected spatial distribution on the gamma-ray sky.
description: Comments: 6 pages, 5 figures, Accepted for publication in Astrophysics and Space Science, Proc. of "The Multi-Messenger Approach to High-Energy Gamma-ray Sources (Third Workshop on the Nature of Unidentified High-Energy Sources)", Barcelona, July 4-7, 2006
Analysis of Within-Host Evolution of Plasmodium falciparum during Treatment with Artemisinin Combination Therapies
Creators: name: Javan Okendo
name: Andagalu, Ben
name: Mulder, Nicola
Publisher: name: AAS Open Research
Year: 2019

description: Antimalarial drugs impose a strong selective pressure on Plasmodium falciparum (P. falciparum) parasite genome and leave signatures of selection. The evolutionary basis of drug resistant malaria in endemic and epidemic settings remains a scientific priority whose solution carries a significant effect on treatment outcomes. Even though there was an increase in the number of non-synonymous point mutations in the Pfk13 gene, the Kenyan P. falciparum strains remained sensitive to ACT drugs. Further research needs to be done by deep sequencing this location of chromosome 13 as it will provide more power for finding novel SNPs for further validation.
Iron oxide-mediated semiconductor photocatalysis vs. heterogeneous photo-Fenton treatment of viruses in wastewater. Impact of the oxide particle size.
Creators: name: Giannakis, Stefanos
Publisher: name: figshare
Year: 2024
Subjects: classificationCode: 401199
subject: Environmental engineering not elsewhere classified

description: Pre-proof versionThe photo-Fenton process is recognized as a promising technique towards microorganism disinfection in wastewater, but its efficiency is hampered at near-neutral pH operating values. In this work, we overcome these obstacles by using the heterogeneous photo-Fenton process as the default disinfecting technique, targeting MS2 coliphage in wastewater. The use of low concentrations of iron oxides in wastewater without H2O2 (wüstite, maghemite, magnetite) has demonstrated limited semiconductor-mediated MS2 inactivation. Changing the operational pH and the size of the oxide particles indicated that the isoelectric point of the iron oxides and the active surface area are crucial in the success of the process, and the possible underlying mechanisms are investigated. Furthermore, the addition of low amounts of Fe-oxides (1 mg L-1) and H2O2 in the system (1, 5 and 10 mg L-1) greatly enhanced the inactivation process, leading to heterogeneous photo-Fenton processes on the surface of the magnetically separable oxides used. Additionally, photo-dissolution of iron in the bulk, lead to homogeneous photo-Fenton, further aided by the complexation by the dissolved organic matter in the solution. Finally, we assess the impact of the presence of the bacterial host and the difference caused by the different iron sources (salts, oxides) and the Fe-oxide size (normal, nano-sized).
Biexciton Initialization by Two-Photon Excitation in Site-Controlled Quantum Dots: the Complexity of the Antibinding State Case
Creators: name: Juska, Gediminas
name: Jahromi, Iman Ranjbar
name: Mattana, Francesco
name: Varo, Simone
name: Dimastrodonato, Valeria
name: Pelucchi, Emanuele
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In this work, we present a biexciton state population in (111)B oriented site-controlled InGaAs quantum dots (QDs) by resonant two photon excitation. We show that the excited state recombines emitting highly pure single photon pairs entangled in polarization. The discussed cases herein are compelling due to the specific energetic structure of Pyramidal InGaAs QDs - an antibinding biexciton - a state with a positive binding energy. We demonstrate that resonant two-photon excitation of QDs with antibinding biexcitons can lead to a complex excitation-recombination scenario. We systematically observed that the resonant biexciton state population is competing with an acoustic-phonon assisted population of an exciton state. These findings show that under typical two-photon resonant excitation conditions deterministic biexciton state initialization can be compromised. This complication should be taken into account by the community members aiming to utilise similar epitaxial QDs with an antibinding biexciton.
Analysis of four-wave mixing of high-power lasers for the detection of elastic photon-photon scattering
Creators: name: Lundin, J.
name: Marklund, M.
name: Lundstrom, E.
name: Brodin, G.
name: Collier, J.
name: Bingham, R.
name: Mendonca, J. T.
name: Norreys, P.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We derive expressions for the coupling coefficients for electromagnetic four-wave mixing in the non-linear quantum vacuum. An experimental setup for detection of elastic photon-photon scattering is suggested, where three incoming laser pulses collide and generate a fourth wave with a new frequency and direction of propagation. An expression for the number of scattered photons is derived and, using beam parameters for the Astra Gemini system at the Rutherford Appleton Laboratory, it is found that the signal can reach detectable levels. Problems with shot-to-shot reproducibility are reviewed, and the magnitude of the noise arising from competing scattering processes is estimated. It is found that detection of elastic photon-photon scattering may for the first time be achieved.
description: 11 pages, 6 figures, to appear in Physical Review A
The United Nations World Conferences on Women : a new South-North dialogue?
Creators: name: Schittecatte, Catherine
Publisher: name: University of British Columbia
Year: 2009

description: The purpose of international conferences sponsored by the United Nations is to provide the international community with the opportunity to debate issues of global concern and reach consensus on objectives and solutions that address these concerns. Since 1975, women have been the focus of a series of such conferences. Among the topics of concern was the marginalization of women which was attributed in part to inadequate international development implementation. This thesis queries whether twenty years of specific focus on women have improved the lives of women in developing countries. A comparative historical analysis of the United Nations World Conferences on Women traces the evolution of the idea of women as a specific constituency of development. The analysis centres around two main questions: (i) whether the conferences addressed relevant issues in a manner that would be conducive to satisfactory solutions, and (ii) whether changes in development implementation occurred as a result and, if so, whether such implementation brought results. In order to answer these questions, the thesis examines the dynamics among the various actors involved in these conferences and in international development implementation. A case study of population policies follows in order to illustrate some empirical assessment of the outcome of twenty years of focus on women in development. The analysis divides actors in two groups, exposing their impact on development and the world conferences on women and vice versa. The first group consists of the nation states and the UN system involved in the South-North debate. The second group consists of the advocates of women as a constituency of development and the development community. The dynamics amongst these actors is linked to the objectives of the world conferences in an interactive manner. The historical evolution of the idea of women as a constituency of development reveals that some beneficial headway for women has been made. Whereas the overall picture of living standards for the majority of the populations in the South, including women, have not improved significantly, the world conferences on women have gained considerable clout in the international community thus influencing development perspectives and implementation. Empirical evidence supports the notion, that tangible progress has been made in sectoral areas of development focusing on women. These results are mainly attributable to a convergence of objectives among the actors considered.
Ethical Issues for Verbal Autopsy in Health and Demographic Surveillance Systems within sub-Saharan Africa
Creators: name: Hinga, Alex
name: V. Marsh
name: S.  Molyneux
Publisher: name: AAS Open Research
Year: 2019

description: Many African countries lack effective systems to record births, marriages, migration, deaths and causes of deaths nationally. This makes it challenging to make public policies, implement public health programmes and to determine whether interventions work. However, some African countries have health and demographic surveillance systems (HDSS) which record births and deaths but in a small population. Most HDSS determine the causes of death through a method called verbal autopsy (VA). The VA involves interviewing close relatives of a recently deceased person to find out the signs, symptoms that led to a death. Ethical issues for verbal autopsy such as its benefits and burdens have received little attention in ethics research and guidelines.
We interviewed individuals with first-hand experience of living in an HDSS area, managing HDSS and of collecting VA data in Kenya, Ghana, Uganda and Malawi. We also observed VA data collection and reviewed unpublished documents.
Emotional distress for VA interviewees and interviewers was the most commonly described burden of VA. Provision of the cause of death information was widely reported as the key benefit of VA, but more evidence is needed on how VA data have been used. The balance of burdens and benefits of VA for individuals and institutions need careful consideration.
An efficient second-order energy stable BDF scheme for the space fractional Cahn-Hilliard equation
Creators: name: Zhao, Yong-Liang
name: Li, Meng
name: Ostermann, Alexander
name: Gu, Xian-Ming
Publisher: name: arXiv
Year: 2020
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: The space fractional Cahn-Hilliard phase-field model is more adequate and accurate in the description of the formation and phase change mechanism than the classical Cahn-Hilliard model. In this article, we propose a temporal second-order energy stable scheme for the space fractional Cahn-Hilliard model. The scheme is based on the second-order backward differentiation formula in time and a finite difference method in space. Energy stability and convergence of the scheme are analyzed, and the optimal convergence orders in time and space are illustrated numerically. Note that the coefficient matrix of the scheme is a $2 \times 2$ block matrix with a Toeplitz-like structure in each block. Combining the advantages of this special structure with a Krylov subspace method, a preconditioning technique is designed to solve the system efficiently. Numerical examples are reported to illustrate the performance of the preconditioned iteration.
description: 26 pages, 5 tables, 4 figures
The last integrable case of kozlov-Treshchev Birkhoff integrable potentials
Creators: name: Damianou, Pantelis A.
name: Papageorgiou, Vassilis
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 37J35, 70H06

description: We establish the integrability of the last open case in the Kozlov-Treshchev classification of Birkhoff integrable Hamiltonian systems. The technique used is a modification of the so called quadratic Lax pair for $D_n$ Toda lattice combined with a method used by M. Ranada in proving the integrability of the Sklyanin case.
description: 13 pages
Clinical Efficacy and Safety of Artemisinin-based combination therapies (ACT) in Cameroon: systematic review and meta-analysis (2006-2018)
Creators: name: Akindeh M.  Nji
name: Niba, Peter Thelma Ngwa
name: Ali, Innocent M.
name: Ngwafor, Randolph
name: Moyeh, Marcel N.
name: Fosah, Dorothy A.
name: Atogho-Tiedeu, Barbara
name: Netongo, Palmer Masumbe
name: Mbanwi, Cyrille
name: Talla, Esther
name: Bigoga, Jude D.
name: Leke, Rose GF.
name: Mbacham, Wilfred F.
Publisher: name: AAS Open Research
Year: 2019

description: Objective: Artemisinin combination therapies(ACT) for the treatment of malaria have shown very high cure rates and with little side effects since it was introduced less that two decades ago. Continuous monitoring of these drugs could sustain this efficacy . In this study we have collected results from many studies that evaluate the cure rates and safety of these drugs to estimate the combined cure rates of these drugs from 2006 to 2018.
Methods: we searched published articles from databases from all known websites that publish articles. We also included unpublished data from dissertations. we used R software version 3.5.2 to do our analysis. There were differences in the studies we evaluated and therefore we used a method of combining the results from non similar studies called Random effects Model.
Results: We evaluated 17 studies with about 3,747 participants in total. The combined cure rates of the ACTs was 98%. The 1st line drugs (Artesunate-Amodiaquine and Arthemeter Lumefantrine) have a combined cure rate estimate of 98.88% and 97.17% respectively. The few side effects were mostly, diarrhea, abdominal pain, nausea and vomiting, headache and dizziness.
Conclusion: Artemisinin drugs in Cameroon over the past 10 years still have high cure rates with little or no side effects. 
title: Αριθμητική διερεύνηση της σεισμικής απόκρισης πασσάλου υπό καθεστώς ρευστοποίησης και οριζόντιας μετατόπισης του εδάφους
titleType: AlternativeTitle
title: Numerical Investigation of pile response under liquefaction and ground lateral spreading
Creators: name: Chaloulos, Yannis K.
Publisher: name: National Technological University of Athens
Year: 2012
Subjects: Ρευστοποίηση
Πλευρική εξάπλωση
Πάσσαλοι
Αριθμητική Προσομοίωση
Άμμοι
Διεύρυνση κοιλότητας
Καμπύλες p-y
P-y curves
Liquefaction
Lateral spreading
Piles
Numerical simulation
Sands
Cavity expansion

description: 442 σ.
description: Αντικείμενο της Διατριβής είναι η συστηματική διερεύνηση των μηχανισμών που επιδρούν στις καμπύλες p-y για πασσάλους σε άμμο υπό οριζόντια φορτία λόγω μετακίνησης του εδάφους, καθώς και η διατύπωση νέων σχέσεων υπολογισμού. Για τον σκοπό αυτό αναπτύχθηκε και τεκμηριώθηκε, μέσω σύγκρισης με πειράματα φυγοκεντριστή, μια τρι-διάστατη αριθμητική μεθοδολογία προσομοίωσης του φαινομένου με κύρια χαρακτηριστικά: (α) τη δυνατότητα προσομοίωσης τόσο έγχυτων όσο και εμπηγνυόμενων πασσάλων και (β) την εισαγωγή ενός νέου τύπου συνόρων ελεύθερου πεδίου για την ακριβή προσομοίωση των συνθηκών του απειρομήκους πρανούς. Αναφορικά σε εδάφη με ρευστοποίηση, οι προτεινόμενες σχέσεις αναθεωρούν βασικές παραδοχές των υφιστάμενων και εισάγουν στον υπολογισμό πρόσθετες παραμέτρους (π.χ. μέθοδος εγκατάστασης). Αναφορικά σε εδάφη χωρίς ρευστοποίηση υπό πλευρική εξάπλωση, οι προτεινόμενες σχέσεις, σε αντίθεση με τις υφιστάμενες, λαμβάνουν υπόψη την έντονη διαστολικότητα που μπορεί να αναπτυχθεί, υπό προϋποθέσεις (π.χ. περιορισμένη δυνατότητα στράγγισης, μεγάλες μετακινήσεις), κοντά στην επιφάνεια και τη συνεπαγόμενη σημαντική αύξηση των επιβαλλόμενων πιέσεων.
description: The Thesis deals with the systematic investigation of the mechanisms that govern p-y response of piles in sands, undergoing lateral loads due to large ground displacement, as well as the development of new multivariable relationships. For this purpose, a 3-dimensional numerical methodology was developed and verified against centrifuge tests. The main characteristics of the methodology are: (a) the capability to simulate both excavated and driven piles and (b) the development of a new type of free field boundaries for the accurate simulation of the kinematics of infinite slopes. As for soils without liquefaction, the proposed relations revise basic concepts of existing methodologies and introduce new parameters in the computations (e.g. pile installation method). As for soils with liquefaction undergoing lateral spreading, the proposed relations, contrary to existing methodologies, take into account the severe dilation that can take place, under certain conditions (e.g. limited drainage capability, large displacements), close to the ground surface, and the consequent large increase of the imposed loads from the surrounding soil.
Barriers and Challenges of Computing Students in an Online Learning Environment: Insights from One Private University in the Philippines
Creators: name: Fabito, Bernie S.
name: Trillanes, Arlene O.
name: Sarmiento, Jeshnile R.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computers and Society (cs.CY)
subject: FOS: Computer and information sciences

description: While the literature presents various advantages of using blended learning, policymakers must identify the barriers and challenges faced by students that may cripple their online learning experience. Understanding these barriers can help academic institutions craft policies to advance and improve the students' online learning experience. This study was conducted to determine the challenges of computing students in one private University in the Philippines during the period where the entire Luzon region was placed under the Enhanced Community Quarantine (ECQ) as a response to the COVID-19 pandemic. A survey through MS Forms Pro was performed to identify the experiences of students in online learning. The survey ran from March 16 to March 18, 2020, which yielded a total of 300 responses. Descriptive statistics revealed that the top three barriers and challenges encountered by students were 1. the difficulty of clarifying topics or discussions with the professors, 2.the lack of study or working area for doing online activities, and 3. the lack of a good Internet connection for participating in online activities. It can be concluded that both students and faculty members were not fully prepared to undergo full online learning. More so, some faculty members may have failed to adapt to the needs of the students in an online learning environment. While the primary data of the study mainly came from the students, it would also be an excellent addition to understand the perspective of the faculty members in terms of their experiences with their students. Their insights could help validate the responses in the survey and provide other barriers that may not have been included in the study.
description: 18 pages, 1 table, 7 figures
Precise radio astrometry and new developments for the next generation of instruments
Creators: name: Rioja, María
name: Dodson, Richard
Publisher: name: arXiv
Year: 2020
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: We present a technique-led review of the progression of precise radio astrometry, from the first demonstrations, half a century ago, until to date and into the future. We cover the developments that have been fundamental to allow high accuracy and precision astrometry to be regularly achieved. We review the opportunities provided by the next-generation of instruments coming online, which are primarily: SKA, ngVLA and pathfinders, along with EHT and other (sub)mm-wavelength arrays, Space-VLBI, Geodetic arrays and optical astrometry from GAIA. From the historical development we predict the future potential astrometric performance, and therefore the instrumental requirements that must be provided to deliver these. The next-generation of methods will allow ultra-precise astrometry to be performed at a much wider range of frequencies (hundreds of MHz to hundreds of GHz). One of the key potentials is that astrometry will become generally applicable, and therefore unbiased large surveys can be performed. The next-generation methods are fundamental in allowing this. We review the small but growing number of major astrometric surveys in the radio, to highlight the scientific impact that such projects can provide. Based on these perspectives, the future of radio astrometry is bright. We foresee a revolution coming from: ultra-high precision radio astrometry, large surveys of many objects, improved sky coverage and at new frequency bands other than those available today. These will enable the addressing of a host of innovative open scientific questions in astrophysics.
In silico prediction of potential antimalarial drug candidates through genomic analysis
Creators: name: Agamah, Francis
name: ER  Chimusa
name: G  Mazandu
name: A  Ghansah
Publisher: name: AAS Open Research
Year: 2019

description: Introduction:
Plasmodium falciparum malaria, an infectious disease, kills lot of people especially in Africa. The parasites have developed resistance to artemisinin, the most active component of artemisinin combination therapies(ACTs) in Southeast Asia. Researching into new drugs, particularly, population-specific, is critical even as measures are instituted to control resistance.

Objectives:
The objective is to identify protein targets that could facilitate predicting potential drug candidates specific to the African populations through a comparative host and Plasmodium falciparum genomic analysis.

Method:
We leveraged malaria-specific genome-wide association study summary statistics data from African populations and malaria-associated genes and functional datasets to construct biological network for human and pathogen. Bioinformatics tools and approaches were used to analyze the networks to identify connected subnetworks. Pharmaceutical datasets and natural products would be screened against potential targets to identify repurposable and novel drug molecules.

Preliminary results:
Significant SNPs from the summary statistics data were mapped to genes. Falciparum PPIs dataset, human-falciparum dataset, human PPIs dataset and micro-array data were obtained from literature and databases. Pairwise interactions obtained through sequence BLAST together with the other datasets were integrated into a unified network.

Conclusions/Next steps:
Pathways enrichment analysis would be performed to identify key genes and biological processes that could be potential drug targets for drug discovery.