cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
A novel representation of an integrated correlator in $\mathcal{N}=4$ SYM theory
Creators: name: Dorigoni, Daniele
name: Green, Michael B.
name: Wen, Congkao
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: An integrated correlator of four superconformal stress-tensor primaries of $\mathcal{N}=4$ supersymmetric $SU(N)$ Yang-Mills theory (SYM), originally obtained by localisation, is re-expressed as a two-dimensional lattice sum that is manifestly invariant under $SL(2,\mathbb{Z})$ S-duality. This expression is shown to satisfy a novel Laplace equation in the complex coupling constant $τ$ that relates the $SU(N)$ integrated correlator to those of the $SU(N+1)$ and $SU(N-1)$ theories. The lattice sum is shown to precisely reproduce known perturbative and non-perturbative properties of $\mathcal{N}=4$ SYM for any finite $N$, as well as extending previously conjectured properties of the large-$N$ expansion.
description: 5 pages; v2: typos corrected, matches published version in PRL
Cosmic-Ray proton spectrum below 100 TeV in the local region
Creators: name: Satyendra, Thoudam
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The propagation of cosmic-ray protons in the Galaxy is discussed under the framework of a three dimensional convection-diffusion model. Starting with the assumption of a uniform and continuous distribution of cosmic-ray sources injecting CRs continuously in the Galaxy and by invoking a supernova explosion at various distances from the Earth, it is found that only those sources located within a distance of ~ 1.5 kpc can produce appreciable temporal fluctuations in the CR proton flux observed at the Earth. So, the construction of the local CR proton spectrum is discussed by seperating the contributions of the distant sources from that of the nearby sources. The contribution from the distant sources is treated in the framework of a continuous source distribution model both in space as well as time, but that of the nearby sources in a discrete space-time source model. The study predicts the presence of at least one old nearby source with a characteristic age of ~ 10^5 yrs located at a distance of ~ 0.1 kpc to explain the observed proton flux below ~ 100 GeV.
description: 8 pages, 6 figures, 1 table, uses mn2e.cls, minor text corrections, accepted for publication in MNRAS
title:  Wrath and Relationships: Homicide Weapon Choice and Victim Offender Relationships
Creators: name: Gonnella, Joseph
Publisher: name: Old Dominion University Libraries
Year: 2021

description: The purpose of this study is to examine the influence that victim-offender relationships and the event circumstances have on homicide weapon choice. From Cornish and Clarke’s Rational Choice theoretical perspective, offenders go through decision- making processes to determine which weapon will be the most effective to meet their goal, based on the circumstances of the event. This study examined the use of three weapon types: firearms, knife/ blunt objects, and personal weapons, amongst victim-offender relationships such as acquaintance, intimate, non-intimate family/friend, and strangers along with circumstances such as homicides committed as the result of a felony, and homicides committed as a result of an argument. Results show that firearms were used the most by strangers, and in felony circumstances, while knife/ blunt objects and personal weapons were used the most by non-intimate family/ friends and in argument circumstances.
Model selection for Poisson processes
Creators: name: Birgé, Lucien
Publisher: name: arXiv
Year: 2006
Subjects: subject: Statistics Theory (math.ST)
subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: 62M30, 62G05 (Primary) 62G10, 41A45, 41A46 (Secondary)

description: Our purpose in this paper is to apply the general methodology for model selection based on T-estimators developed in Birgé [Ann. Inst. H. Poincaré Probab. Statist. 42 (2006) 273--325] to the particular situation of the estimation of the unknown mean measure of a Poisson process. We introduce a Hellinger type distance between finite positive measures to serve as our loss function and we build suitable tests between balls (with respect to this distance) in the set of mean measures. As a consequence of the existence of such tests, given a suitable family of approximating models, we can build T-estimators for the mean measure based on this family of models and analyze their performances. We provide a number of applications to adaptive intensity estimation when the square root of the intensity belongs to various smoothness classes. We also give a method for aggregation of preliminary estimators.
description: Published at http://dx.doi.org/10.1214/074921707000000265 in the IMS Lecture Notes Monograph Series (http://www.imstat.org/publications/lecnotes.htm) by the Institute of Mathematical Statistics (http://www.imstat.org)
Αξιοποίηση των κοινωνικών δικτύων στην εκμάθηση της Ιταλικής γλώσσας
Creators: name: Βαραδίνη, Δόμνα Παντελή
Publisher: name: Aristotle University of Thessaloniki
Year: 2018
Subjects: Κοινωνικά δίκτυα
Ιταλική γλώσσα
Edmodo
Social networks
Italian language

description: Είναι γεγονός ότι την τελευταία δεκαετία υπάρχει ένα έντονο ενδιαφέρον προς τα κοινωνικά δίκτυα είτε για κοινωνικούς, είτε για επαγγελματικούς είτε και για εκπαιδευτικούς σκοπούς. Ολοένα και περισσότεροι χρήστες του διαδικτύου δημιουργούν προφίλ σε αυτά τα δίκτυα με σκοπό την ψυχαγωγία και τη δημιουργική συμμετοχή σε αυτά, τα οποία αποτελούν πλέον αναπόσπαστο κομμάτι της κοινωνικής και πολιτιστικής τους πραγματικότητας. Σκοπός της παρούσας εργασίας είναι να διερευνήσει τον τρόπο με τον οποίο τα κοινωνικά δίκτυα χρησιμοποιούνται στην εκμάθηση ξένων γλωσσών και ιδιαίτερα στην εκμάθηση της ιταλικής γλώσσας και, επιπλέον, να προτείνει ένα κοινωνικό δίκτυο, το οποίο δημιουργήθηκε για το σκοπό αυτό. Μέσα από έρευνες και μελέτες που πραγματοποιήθηκαν στο παρελθόν αναλύονται πρώτα από όλα οι λόγοι για τους οποίους αποφασίστηκε η παρουσίαση των πλατφορμών Elgg, Ning, Sit και Edmodo καθώς και οι λόγοι που οδήγησαν στην εφαρμογή του δικτύου Edmodo σε ένα μάθημα ιταλικής γλώσσας. Στην περίληψη περιλαμβάνεται ο αντίκτυπος αυτής της εφαρμογής. Τέλος, γίνεται μια σύντομη αναφορά στα οφέλη και στις δυσμένειες της κοινωνικής δικτύωσης καθώς επίσης και μια σύνοψη των αποτελεσμάτων της εφαρμογής όπου διατυπώνονται συμπεράσματα και προτάσεις για μελλοντική έρευνα.
description: It is a fact that over the past decade there has been a keen interest in social networks, whether for social, professional or educational purposes. More and more Internet users are creating profiles on these networks with the aim of entertainment and the creative participation in them, which now constitute an integral part of their social and cultural reality. The purpose of this MA Thesis is to explore how the social networks are used in foreign language learning and especially in learning the Italian language and, moreover, to suggest a model social network, created for this aim. Through researches and studies conducted in the past, is analyzed first of all the reasons why it is decided to present the Elgg, Ning, Sit and Edmodo platforms and also the reasons about implementation of the Edmodo network in an Italian language course . In the summary is included the impact of this implementation.
FirstLight IV: Diversity in sub-L$_*$ galaxies at cosmic dawn
Creators: name: Ceverino, Daniel
name: Hirschmann, Michaela
name: Klessen, Ralf
name: Glover, Simon
name: Charlot, Stephane
name: Feltre, Anna
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Using a large sample of sub-L$_*$ galaxies, with similar UV magnitudes, M$_{\rm UV}\simeq -19$ at $z\simeq6$, extracted from the FirstLight simulations, we show the diversity of galaxies at the end of the reionization epoch. We find a factor $\sim$40 variation in the specific star-formation rate (sSFR). This drives a $\sim$1 dex range in equivalent width of the [OIII]$λ$5007 line. Variations in nebular metallicity and ionization parameter within HII regions lead to a scatter in the equivalent widths and [OIII]/H$α$ line ratio at a fixed sSFR. [OIII]-bright emitters ([OIII]/H$α$>1) have higher ionization parameters and/or higher metallicities than H$α$-bright ([OIII]/H$α$<1) galaxies. According to the surface brightness maps in both [OIII] and H$α$, [OIII]-bright emitters are more compact than H$α$-bright galaxies. H$α$ luminosity is higher than [OIII] if star formation is distributed over extended regions. OIII dominates if it is concentrated in compact clumps. In both cases, the H$α$-emitting gas is significantly more extended than [OIII].
description: 9 pages, 5 figures, accepted at MNRAS. The website of the FirstLight database can be found at http://odin.ft.uam.es/FirstLight/index.html
Spin relaxation times in disordered graphene
Creators: name: Huertas-Hernando, Daniel
name: Guinea, Francisco
name: Brataas, Arne
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We consider two mechanisms of spin relaxation in disordered graphene. i) Spin relaxation due to curvature spin orbit coupling caused by ripples. ii) Spin relaxation due to the interaction of the electronic spin with localized magnetic moments at the edges. We obtain analytical expressions for the spin relaxation times, tau_SO and tau_J due to both mechanisms and estimate their values for realistic parameters of graphene samples. We obtain that spin relaxation originating from these mechanisms is very weak and spin coherence is expected in disordered graphene up to samples of length L ~ 1 micron.
description: To appear in the Proceedings of the Graphene Conference, MPI PKS Dresden, September 2006. Corrected typos
Surface topography of tracheal cells of common tree shrew (Tupaia glis)
Creators: name: Busaba Panyarachun, Arin Ngamniyom
Publisher: name: Faculty of Medicine,Srinakharinwirot University
Year: 2009
Subjects: trachea, ciliated cell, non-ciliated cell, goblet cell, scanning electron microscopy

description: 3, 17, Journal of Medicine and Health Sciences
Machine Learning based optimization for interval uncertainty propagation
Creators: name: Cicirello, Alice
name: Giunta, Filippo
Publisher: name: arXiv
Year: 2021
Subjects: subject: Signal Processing (eess.SP)
subject: Machine Learning (cs.LG)
subject: Optimization and Control (math.OC)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Two non-intrusive uncertainty propagation approaches are proposed for the performance analysis of engineering systems described by expensive-to-evaluate deterministic computer models with parameters defined as interval variables. These approaches employ a machine learning based optimization strategy, the so-called Bayesian optimization, for evaluating the upper and lower bounds of a generic response variable over the set of possible responses obtained when each interval variable varies independently over its range. The lack of knowledge caused by not evaluating the response function for all the possible combinations of the interval variables is accounted for by developing a probabilistic description of the response variable itself by using a Gaussian Process regression model. An iterative procedure is developed for selecting a small number of simulations to be evaluated for updating this statistical model by using well-established acquisition functions and to assess the response bounds. In both approaches, an initial training dataset is defined. While one approach builds iteratively two distinct training datasets for evaluating separately the upper and lower bounds of the response variable, the other builds iteratively a single training dataset. Consequently, the two approaches will produce different bound estimates at each iteration. The upper and lower bound responses are expressed as point estimates obtained from the mean function of the posterior distribution. Moreover, a confidence interval on each estimate is provided for effectively communicating to engineers when these estimates are obtained for a combination of the interval variables for which no deterministic simulation has been run. Finally, two metrics are proposed to define conditions for assessing if the predicted bound estimates can be considered satisfactory.
description: V2 - Preprint submitted to Mechanical Systems and Signal Processing
Reconstruction of a large full-thickness abdominal wall defect using free latissimus dorsi muscle flap: A case report
Creators: name: Poonpissamai Suwajo
Publisher: name: Faculty of Medicine,Srinakharinwirot University
Year: 2009
Subjects: abdominal wall defect, abdominal wall reconstruction, latissimus dorsi flap

description: 3, 16, Journal of Medicine and Health Sciences
Two-Stage TMLE to Reduce Bias and Improve Efficiency in Cluster Randomized Trials
Creators: name: Balzer, Laura B.
name: van der Laan, Mark
name: Ayieko, James
name: Kamya, Moses
name: Chamie, Gabriel
name: Schwab, Joshua
name: Havlir, Diane V.
name: Petersen, Maya L.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Methodology (stat.ME)
subject: Applications (stat.AP)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: Cluster randomized trials (CRTs) randomly assign an intervention to groups of individuals (e.g., clinics or communities) and measure outcomes on individuals in those groups. While offering many advantages, this experimental design introduces challenges that are only partially addressed by existing analytic approaches. First, outcomes are often missing for some individuals within clusters. Failing to appropriately adjust for differential outcome measurement can result in biased estimates and inference. Second, CRTs often randomize limited numbers of clusters, resulting in chance imbalances on baseline outcome predictors between arms. Failing to adaptively adjust for these imbalances and other predictive covariates can result in efficiency losses. To address these methodological gaps, we propose and evaluate a novel two-stage targeted minimum loss-based estimator (TMLE) to adjust for baseline covariates in a manner that optimizes precision, after controlling for baseline and post-baseline causes of missing outcomes. Finite sample simulations illustrate that our approach can nearly eliminate bias due to differential outcome measurement, while existing CRT estimators yield misleading results and inferences. Application to real data from the SEARCH community randomized trial demonstrates the gains in efficiency afforded through adaptive adjustment for baseline covariates, after controlling for missingness on individual-level outcomes.
description: 37 pages total; main text is 17 pgs with 2 figures and 3 tables; supp material is 14 pgs with 1 figure and 5 tables
Quantum randomness is chimeric
Creators: name: Svozil, Karl
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: If quantum mechanics is taken for granted the randomness derived from it may be vacuous or even delusional, yet sufficient for many practical purposes. "Random" quantum events are intimately related to the emergence of both space-time as well as the identification of physical properties through which so-called objects are aggregated. We also present a brief review of the metaphysics of indeterminism.
description: 16 pages, 1 figure, added section on information theoretic approach to quantum randomness
HALF: Holistic Auto Machine Learning for FPGAs
Creators: name: Ney, Jonas
name: Loroch, Dominik
name: Rybalkin, Vladimir
name: Weber, Nico
name: Krüger, Jens
name: Wehn, Norbert
Publisher: name: arXiv
Year: 2021
Subjects: subject: Hardware Architecture (cs.AR)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Deep Neural Networks (DNNs) are capable of solving complex problems in domains related to embedded systems, such as image and natural language processing. To efficiently implement DNNs on a specific FPGA platform for a given cost criterion, e.g. energy efficiency, an enormous amount of design parameters has to be considered from the topology down to the final hardware implementation. Interdependencies between the different design layers have to be taken into account and explored efficiently, making it hardly possible to find optimized solutions manually. An automatic, holistic design approach can improve the quality of DNN implementations on FPGA significantly. To this end, we present a cross-layer design space exploration methodology. It comprises optimizations starting from a hardware-aware topology search for DNNs down to the final optimized implementation for a given FPGA platform. The methodology is implemented in our Holistic Auto machine Learning for FPGAs (HALF) framework, which combines an evolutionary search algorithm, various optimization steps and a library of parametrizable hardware DNN modules. HALF automates both the exploration process and the implementation of optimized solutions on a target FPGA platform for various applications. We demonstrate the performance of HALF on a medical use case for arrhythmia detection for three different design goals, i.e. low-energy, low-power and high-throughput respectively. Our FPGA implementation outperforms a TensorRT optimized model on an Nvidia Jetson platform in both throughput and energy consumption.
description: 2021 31st International Conference on Field-Programmable Logic and Applications (FPL). IEEE, 2021
Ideology, social control, and the private facts tort
Creators: name: Henderson, Emma Marilyn
Publisher: name: University of British Columbia
Year: 2009

description: This thesis involves an ideological examination of the Tort of Invasion of Privacy as it has been developed in United States case law, focusing specifically on the private fact component of the tort. The object of inquiry is to examine the extent to which dominant social structures, specifically gender bias and heterosexism, are reinforced and recreated by judicial constructions of the line between private and public facts. To this end the research begins with a theory component which places the law of privacy within the historically and socially contingent dynamic between state, society and the legal system. Having established privacy as a dominant ideological component in the make up of the American legal system, the thesis then turns to case analysis to establish the assertion that the tort, created at a time of considerable societal instability, has operated to restrict and control the behaviour of women, by denying privacy protection to those who step outside of acceptable social roles. The thesis then turns to consider the nature of heterosexism and the manner in which this dominant societal ideology has been interpreted and filtered through the tort, so as to exclude privacy protection to those who do not conform to heterosexual norms, and to grant it to those who keep their (nonheterosexual) sexual identities silent. In short, the thesis attempts to locate the tort in the context of changing social structures, and to examine the manner in which it has operated at an ideological level. Use of this framework allows for an alternative interpretation of the case law, and questions the seemingly neutral face of privacy law both within the common law context and in other fields.
A path-integral molecular dynamics simulation of diamond
Creators: name: Ramirez, Rafael
name: Herrero, Carlos P.
name: Hernandez, Eduardo R.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Diamond is studied by path integral molecular dynamics simulations of the atomic nuclei in combination with a tight-binding Hamiltonian to describe its electronic structure and total energy. This approach allows us to quantify the influence of quantum zero-point vibrations and finite temperatures on both the electronic and vibrational properties of diamond. The electron-phonon coupling mediated by the zero-point vibration reduces the direct electronic gap of diamond by 10 %. The calculated decrease of the direct gap with temperature shows good agreement with the experimental data available up to 700 K. Anharmonic vibrational frequencies of the crystal have been obtained from a linear-response approach based on the path integral formalism. In particular, the temperature dependence of the zone-center optical phonon has been derived from the simulations. The anharmonicity of the interatomic potential produces a red shift of this phonon frequency.At temperatures above 500 K, this shift is overestimated in comparison to available experimental data. The predicted temperature shift of the elastic constant c_{44} displays reasonable agreement with the available experimental results.
description: 9 pages, 9 figures
Statistical Properties of Nuclei by the Shell Model Monte Carlo Method
Creators: name: Alhassid, Y.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Nuclear Theory (nucl-th)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We use quantum Monte Carlo methods in the framework of the interacting nuclear shell model to calculate the statistical properties of nuclei at finite temperature and/or excitation energies. With this approach we can carry out realistic calculations in much larger configuration spaces than are possible by conventional methods. A major application of the methods has been the microscopic calculation of nuclear partition functions and level densities, taking into account both correlations and shell effects. Our results for nuclei in the mass region A ~ 50 - 70 are in remarkably good agreement with experimental level densities without any adjustable parameters and are an improvement over empirical formulas. We have recently extended the shell model theory of level statistics to higher temperatures, including continuum effects. We have also constructed simple statistical models to explain the dependence of the microscopically calculated level densities on good quantum numbers such as parity. Thermal signatures of pairing correlations are identified through odd-even effects in the heat capacity.
description: 6 pages, 6 figures
Πολυπαραγοντική ταυτοποίηση των δινομαστιγωτών Gambierdiscus στις δυτικές ακτές της Κρήτης
Creators: name: Ηλιάδου, Μαρίνα Γεωργίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2018
Subjects: Δυνητικά τοξικά μικροφύκη
Σιγκουατέρα
Κρήτη
Potentially toxic microalgae
Ciguatera
Crete

description: Τα δινομαστιγωτά του γένους Gambierdiscus έχουν την ικανότητα παραγωγής βιοτοξινών οι οποίες συσσωρεύονται στους ιστούς ιχθύων προκαλώντας τη νόσο Ciguatera Fish Poisoning (CFP), γνωστή παλαιότερα στις τροπικές-υποτροπικές περιοχές. Το γένος Gambierdiscus καταγράφηκε πρώτη φορά στη Μεσόγειο (Κρήτη) το 2003, δημιουργώντας έτσι τις προϋποθέσεις για πιθανή εμφάνιση CFP. Προκειμένου να διερευνηθεί αυτό το ενδεχόμενο, έχει εντατικοποιηθεί η μελέτη του γένους σε επίπεδο γεωγραφικής κατανομής, μορφολογικής περιγραφής με τη χρήση μικροσκοπίας ηλεκτρονικής και επιφθορισμού, μοριακής ταυτοποίησης με βάση τις περιοχές SSU και D1-D3/D8-D10 LSU rRNA, καθώς και τοξικότητας. Σύμφωνα με τα αποτελέσματα της παρούσας μελέτης, τουλάχιστον τρία διαφορετικά taxa εντοπίζονται στις δυτικές ακτές της Κρήτης: το Gambierdiscus silvae, ένα δεύτερο είδος, μορφολογικά και γενετικά ταυτόσημο με το Gambierdiscus sp. που είχε αρχικά καταγραφεί στην Κρήτη και ένα τρίτο είδος συγγενικό με το G. belizeanus. Στελέχη των παραπάνω ειδών αναπτύσσονται σε συνθήκες καλλιέργειας για περαιτέρω διερεύνηση της τοξικότητάς τους με τη μέθοδο της κυτταροτοξικότητας σε κυτταρικές σειρές νευροβλαστώματος (N2A). Η διερεύνηση της κυτταροτοξικότητας πραγματοποιήθηκε με την παρατήρηση της μορφολογικής διαφοροποίησης των κυττάρων N2A και με την μέθοδο του ποσοτικού προσδιορισμού κυτταροτοξικότητας MTT.
description: Marine benthic dinoflagellates of the genus Gambierdiscus are known to produce biotoxins which accumulate in fish tissues and cause ciguatera fish poisoning (CFP), a disease known until recently only from tropical and subtropical areas. Gambierdiscus has been recorded in the Mediterranean (Crete) since 2003, raising concern regarding a possible onset of CFP in the area. In order to investigate this risk, research on Gambierdiscus distribution, morphological characterization with epifluorescence and scanning electron microscopy, molecular identification based on the SSU and D1-D3/D8-D10 LSU rRNA regions and toxicity has been recently intensified. The results of the present study indicate the presence of at least three taxa in western Crete: Gambierdiscus silvae, a second taxon, morphologically and genetically identical to Gambierdiscus sp. initially identified in Crete and a third taxon, closely related to G. belizeanus. Strains of the above species are grown in culture conditions for further investigation of their toxicity by the cytotoxicity method in neuroblastoma cell lines (N2A). Investigation of cytotoxicity of strains was conducted by observing the morphological differentiation of N2A cells and by MTT cytotoxicity assay.
Six-loop beta functions in general scalar theory
Creators: name: Bednyakov, Alexander
name: Pikelner, Andrey
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider general renormalizable scalar field theory and derive six-loop beta functions for all parameters in d = 4 dimensions within the $\overline{MS}$-scheme. We do not explicitly compute relevant loop integrals but utilize $O(n)$-symmetric model counter-terms available in the literature. We consider dimensionless couplings and parameters with a mass scale, ranging from the trilinear self-coupling to the vacuum energy. We use obtained results to extend renormalization-group equations for several vector, matrix, and tensor models to the six-loop order. Also, we apply our general expressions to derive new contributions to beta functions and anomalous dimensions in the scalar sector of the Two-Higgs-Doublet Model.
description: 25 pages, matches published version, results in ancillary files
IMPACT OF SOCIAL MEDIA ON YOUTH
Creators: name: Gautam Kumar
Publisher: name: Zenodo
Year: 2025

description: Social media has become an integral and inescapable force in life. Today, the use of Facebook, Instagram, Snapchat, Twitter, and among others, digital spaces have profoundly reshaped the life style of young people: how to communicate, build relationships, learn, and engage with the world around them. It has become a powerful tool of self-expression, entertainment, education, and even activism.

In countries like India, social media has grown at an exponential rate in recent years. A 2023 report suggests that nearly 80% of India's internet users lie in the 18 to 34 age range, making the youth group the largest audience for digital platforms. Social media has spread particularly within urban areas, where young people use them for different purposes-including keeping in touch with friends and family, following celebrities and influencers, contributing to and joining online communities, and pursuing educational content. Other than these, platforms like WhatsApp, YouTube, and Instagram have encouraged new modes of communication and entertainment, allowing youth to consume, create, and share content on an unprecedented scale while social media has opened a plethora of positive opportunities for growth, creativity, and learning, serious concerns also arise regarding its impacts on mental health, academic performance, social behavior, and self-esteem. Given that they are at an age of discovery and self-formation, adolescents may be particularly prone to the adverse effects of the use of social media. Excessive or unhealthy social media use has been linked to increased levels of anxiety, depression, poor body image, and decreased self-worth. Furthermore, the pervasiveness of social comparison, cyberbullying, and the need to create an ideal image online have become raging causes of anxiety and emotional anguish for youngsters.
The Continuous Time Spectrum of Long-Term Activity of the Fast-Rotating K2 Dwarf V833 Tau
Creators: name: Katsova, Maria
name: Bondar', Nataliya
name: Stepanov, Rodion
name: Sokoloff, Dmitry
name: Frick, Peter
Publisher: name: Zenodo
Year: 2021
Subjects: Cool Stars on the main sequence

description: Abstract. The magnetic activity of the Sun and low-mass stars demonstrates often a cyclic behavior. Some stars exhibit solar-like activity cycles, while some show irregular cycles; there are several stars with double or multiple cycles which serve to challenge the underlying theoretical understanding. This is why a consistent method to separate ‘true’ cycles from stochastic variations is required. We suggest that a conservative method, based on the best practice of wavelet analysis previously applied to the study of solar activity, for studying and interpreting the one of the longest available stellar activity record – photometric monitoring of young, fast-rotating dwarf V833 Tau (K2.5 V) for 120 yr. We find that the observed brightness variations of V833 Tau with time-scales of 2–50 yr should be comparable with the known quasi-periodic solar mid-term variations, whereas the true cycle of V833 Tau, if it exists, should be of about a century or even longer. We argue that this conclusion does not contradict the expectations from the stellar dynamo theory. Activity of this star is close to the saturated regime, and we expect, that the stellar dynamo in this mode enhances the quasi-stationary magnetic field with chaotic changes, but without a pronounced cycle. However, we cannot completely exclude the scenario that V833 Tau has essentially an unstable dynamo and its cycle length varies within the period of 10–40 yr.
description: This is a Poster presented for The 20.5th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun ("Cool Stars 20.5")
Home-made rapid urease test compared with histopathologic examination for diagnosis of Helicobacter pylori infection
Creators: name: Chatchawan Wongjitrat, Piyanun Chonmitri
Publisher: name: Faculty of Medicine,Srinakharinwirot University
Year: 2009
Subjects: Helicobacter pylori, home-made rapid urease test

description: 3, 16, Journal of Medicine and Health Sciences
Cosmological Black Holes on Taub-NUT space in Five-Dimensional Einstein-Maxwell Theory
Creators: name: Ida, Daisuke
name: Ishihara, Hideki
name: Kimura, Masashi
name: Matsuno, Ken
name: Morisawa, Yoshiyuki
name: Tomizawa, Shinya
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The cosmological black hole solution on the Gibbons-Hawking space has been constructed. We also investigate the properties of this solution in the case of a single black hole. Unlike the Kastor-Traschen solution, which becomes static Reissner-Nortström de Sitter solution in a single black hole, this solution is not static even in a single black hole case.
description: 12 pages, 4 figures, some minor corrections, to be published in Classical and Quantum Gravity
Gold nanodoughnut as an outstanding nanoheater for photothermal applications
Creators: name: González-Colsa, Javier
name: Serrera, Guillermo
name: Saiz, José María
name: Ortiz, Dolores
name: González, Francisco
name: Bresme, Fernando
name: Moreno, Fernando
name: Albella, Pablo
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Photoinduced hyperthermia is a cancer therapy technique that induces death to cancerous cells via heat generated by plasmonic nanoparticles. While previous studies have shown that some nanoparticles can be effective at killing cancer cells under certain conditions, there is still a necessity (or the need) to improve its heating efficiency. In this work, we perform a detailed thermoplasmonic study comparing the most effective nanoparticle geometries up to now with a doughnut-shaped nanoparticle, demonstrating that the latter exhibits a superior tunable photothermal response in practical illumination conditions, i.e., unpolarized light. Furthermore, we show that nanoparticle heating in fluidic environments, i.e., nanoparticles undergoing Brownian rotations, strongly depends on the particle orientation with respect to the illumination source. We conclude that the heating performance of nanodoughnuts is outstanding, with a temperature increment 35% higher than the second best nanoheater (nanodisks). Furthermore, nanodoughnuts feature a weak dependence on orientation, being therefore, ideal candidates for photothermal therapy applications. Finally, we present a designing guide, covering a wide range of toroid designs, which can help on its experimental implementation.
Enhancing the Motivation and Classroom Engagement of EAP Learners in a Canadian Community College: A Participatory Action Research Approach
Creators: name: Sobhanmanesh, Alireza
Publisher: name: Université d'Ottawa / University of Ottawa
Year: 2021
Subjects: Motivation
Engagement
Participatory Action Research

description: This study aimed to improve the L2 motivation and classroom engagement of 18 English for Academic Purposes (EAP) learners in a college in Toronto, Canada. Guided by L2 Motivational Self Systems (L2MSS) theory and complexity theory as the conceptual theoretical framework, and in line with principles of Participatory Action Research (PAR), the researcher formed a research community with EAP students and their teacher to investigate students’ shifting motivation and their evolving sense of self. As co-researchers, we engaged in data collection inside the classroom through collaborative lesson planning and outside the classroom through a number of social activities. In the end, participants disseminated PAR project findings by presenting in a student forum. Classroom engagement was measured using Experience Sampling Forms (ESFs) that students filled out at the end of each class. Their L2 motivation was measured through semi-structured interviews with a sub-sample of participants (n = 10) during three stages of the project (middle, end, and one year later). Findings indicated that learners’ classroom engagement and motivation improved significantly during the project. As a result of specific interventions inside the classroom (e.g., collaboration among community members, sharing of power, co-teaching, etc.), the group dynamics improved, and a more positive classroom atmosphere was established. Classroom tasks and social activities enabled learners to develop a more vivid ideal L2 self but were also of benefit to learners with a dominant ought-to L2 self. These learners showed a tendency to internalize others’ goals, which energized their learning behaviors in the classroom. On a theoretical level, these results highlight the possibilities for both L2MSS and complexity theory to explain such changes in learner motivation. On a practical level, these findings underscore the motivational value of participatory EAP classes where a balance is reached between social and academic learning.
Can different black holes cast the same shadow?
Creators: name: Junior, Haroldo C. D. Lima
name: Crispino, Luís C. B.
name: Cunha, Pedro V. P.
name: Herdeiro, Carlos A. R.
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider the following question: may two different black holes (BHs) cast exactly the same shadow? In spherical symmetry, we show the necessary and sufficient condition for a static BH to be shadow-degenerate with Schwarzschild is that the dominant photonsphere of both has the same impact parameter, when corrected for the (potentially) different redshift of comparable observers in the different spacetimes. Such shadow-degenerate geometries are classified into two classes. The first shadow-equivalent class contains metrics whose constant (areal) radius hypersurfaces are isometric to those of the Schwarzschild geometry, which is illustrated by the Simpson and Visser (SV) metric. The second shadow-degenerate class contains spacetimes with different redshift profiles and an explicit family of metrics within this class is presented. In the stationary, axi-symmetric case, we determine a sufficient condition for the metric to be shadow degenerate with Kerr for far-away observers. Again we provide two classes of examples. The first class contains metrics whose constant (Boyer-Lindquist-like) radius hypersurfaces are isometric to those of the Kerr geometry, which is illustrated by a rotating generalization of the SV metric, obtained by a modified Newman-Janis algorithm. The second class of examples pertains BHs that fail to have the standard north-south $\mathbb{Z}_2$ symmetry, but nonetheless remain shadow degenerate with Kerr. The latter provides a sharp illustration that the shadow is not a probe of the horizon geometry. These examples illustrate that nonisometric BH spacetimes can cast the same shadow, albeit the lensing is generically different.
description: Matches the version published in Physical Review D, title changed, typos corrected, 16 pages, 8 figures
Sensitivity to Triple Higgs Couplings via Di-Higgs Production in the 2HDM at e+e- Colliders
Creators: name: Arco, F.
name: Heinemeyer, S.
name: Herrero, M. J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: An important task at future colliders is the investigation of the Higgs-boson sector. Here the measurement of the triple Higgs coupling(s) plays a special role. Based on previous analyses, within the framework of Two Higgs Doublet Models (2HDM) type~I and~II, we define and analyze several two-dimensional benchmark planes, that are over large parts in agreement with all theoretical and experimental constraints. For these planes we evaluate di-Higgs production cross sections at future high-energy $e^+e^-$ colliders, such as ILC or CLIC. We consider two different channels for the neutral di-Higgs pairs $h_i h_j=hh,hH,HH,AA$: $e^+e^- \to h_i h_j Z$ and $e^+e^- \to h_i h_j ν\bar ν$. In both channels the various triple Higgs-boson couplings contribute substantially. We find regions with a strong enhancement of the production channel of two SM-like light Higgs bosons and/or with very large production cross sections involving one light and one heavy or two heavy 2HDM Higgs bosons, offering interesting prospects for the ILC or CLIC. The mechanisms leading to these enhanced production cross sections are analyzed in detail. We propose the use of cross section distributions with the invariant mass of the two final Higgs bosons where the contributions from intermediate resonant and non-resonant BSM Higgs bosons play a crucial role. We outline which process at which center-of-mass energy would be best suited to probe the corresponding triple Higgs-boson couplings.
description: 57 pages, 29 figures, lots of plots, version published in Eur.Phys.J.C
Applying machine learning for retail demand forecasting
Creators: name: Κουλούμπρης, Ελευθέριος Νικολάου
Publisher: name: Aristotle University of Thessaloniki
Year: 2018
Subjects: Μηχανική Μάθηση
Πρόβλεψη Ζήτησης
Δεδομένα Λιανικής
Machine Learning
Demand Forecasting
Retail Data

description: Η εργασία αυτή αφορά τη διατύπωση ενός προβλήματος Πρόβλεψης Ζήτησης σε Καταστήματα Λιανικής ως πρόβλημα Μηχανικής Μάθησης, με επίκεντρο τη φάση προγνωστικής μοντελοποίησης. Στο πλαίσιο αυτό, πραγματοποιήθηκε ανάλυση των χαρακτηριστικών ενός πραγματικού συνόλου δεδομένων λιανικής και ο συνδυασμός τους για την κατασκευή νέων χαρακτηριστικών. Τα χαρακτηριστικά αυτά αξιολογήθηκαν μέσω της μετρικής pIncMSE σε δέκα ομάδες προϊόντων. Συγκεκριμένα, τα δεδομένα αφορούσαν τις ημερήσιες πωλήσεις που έλαβαν χώρα σε 3 καταστήματα κατά το διάστημα ενός χρόνου. Επιπλέον, οι προγνωστικές επιδώσεις των μεθόδων ARIMA, Random Forest και XGBoost, καθώς και αυτές τριών μεθόδων αναφοράς αξιολογήθηκαν στις προαναφερθείσες ομάδες. Για την πραγματοποίηση αυτής της αξιολόγησης εκτιμήθηκε το μέσο MASE της κάθε ομάδας. Η μέθοδος XGBoost είχε την καλύτερη επίδοση σε όλες τις ομάδες, ακολουθούμενη από τις Random Forest και ARIMA. Τα εκτιμώμενα μέσα MASE των ομάδων ήταν 0.93 για τις μεθόδους αναφοράς, 0.79 για το ARIMA, 0.29 για το Random Forest και 0.21 για το XGBoost.
description: The purpose of this work regards the formulation of a Retail Demand Forecasting (RDF) problem as a Machine Learning problem, with a focus on the phase of predictive modeling. In this context, the features of a real RDF dataset were analyzed and combined in order to engineer new features. These features were then evaluated via the estimation of the pIncMSE metric on ten groups of products. Specifically, the data regarded the daily sales that took place in three stores over a period of one year. Furthermore, the predictive performances of the methods ARIMA, Random Forest and XGBoost, as well as those of three benchmark methods, were evaluated on the aforementioned groups. The estimated average MASE for each group was used for this evaluation. XGBoost was the best performing method in all groups, followed by Random Forest and then ARIMA. The estimated average group MASE values were 0.93 for the benchmark methods, 0.79 for ARIMA, 0.29 for Random Forest and 0.21 for XGBoost.
On stochastic heating and its phase-space signatures in low-$β$ kinetic turbulence
Creators: name: Cerri, Silvio Sergio
name: Arzamasskiy, Lev
name: Kunz, Matthew W.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Plasma Physics (physics.plasm-ph)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: We revisit the theory of stochastic heating of ions and investigate its phase-space signatures in kinetic turbulence of relevance to low-$β$ portions of the solar wind. We retain a full scale-dependent approach in our treatment, and consider the case in which electric-field fluctuations can be described by a generalized Ohm's law that includes Hall and thermo-electric effects. These two electric-field terms provide the dominant contributions to stochastic ion heating when the ion-Larmor scale is much smaller than the ion skin depth, $ρ_{\mathrm{i}}\ll d_{\mathrm{i}}$, which is the case at $β{\ll}1$. Employing well-known spectral scaling laws for Alfvén-wave and kinetic-Alfvén-wave turbulent fluctuations, we obtain scaling relations characterizing the field-perpendicular particle-energization rate and energy diffusion coefficient associated with stochastic heating in these two regimes. Phase-space signatures of ion heating are then investigated using 3D hybrid-kinetic simulations of continuously driven Alfvénic turbulence at low $β$. In these simulations, energization of ions parallel to the magnetic field is sub-dominant compared to its perpendicular counterpart ($Q_{\parallel,\mathrm{i}}\ll Q_{\perp,\mathrm{i}}$), and the fraction of turbulent energy that goes into ion heating is ${\approx}75$\% at $β_{\mathrm{i}}=0.3$ and ${\approx}40$\% at $β_{\mathrm{i}}{\simeq}0.1$. The phase-space signatures of ion energization are consistent with Landau-resonant collisionless damping and a ($β$-dependent) combination of ion-cyclotron and stochastic heating. We demonstrate good agreement between our theory and various signatures associated with the stochastic portion of the heating. We discuss the effect of intermittency on stochastic heating and the implications of our work for the interpretation of stochastic heating in solar-wind spacecraft data.
description: 23 pages, 9 figures (and 20 footnotes); accepted for publication in The Astrophysical Journal
Ενοποίηση πληροφοριακών συστημάτων με ESB Ανοιχτού κώδικα
Creators: name: Σαββάκης, Χρυσοβαλάντης Θωμά
Publisher: name: Aristotle University of Thessaloniki
Year: 2018
Subjects: subject: Ενοποίηση
subject: Επιχειρησιακή Υπηρεσία Λεωφορείου
subject: Πληροφοριακά Συστήματα
subject: Integration
subject: Enterprise Service Bus
subject: Information Systems
subject: FOS: Computer and information sciences

description: Οι αυξημένες ανάγκες των επιχειρήσεων οδήγησαν στην υιοθέτηση αρκετών πληροφοριακών συστημάτων για την καλύτερη διαχείριση των επιχειρηματικών τους δραστηριοτήτων. Για να μπορέσουν να είναι βιώσιμες στον ανταγωνισμό υπάρχει η ανάγκη για ολοκληρωτική αξιοποίηση αυτών των συστημάτων. Οι επιχειρήσεις κάνοντας αυτές τις διαφορετικές εφαρμογές λογισμικού και τις υπηρεσίες να συνεργάζονται, παράγουν ενιαία επιχειρηματική λειτουργικότητα και προστιθέμενη αξία στις υπάρχουσες εφαρμογές. Επίσης έχουν τη δυνατότητα να προσφέρουν ταχύτερες και ποιοτικότερες υπηρεσίες προς τους ενδιαφερόμενους πελάτες τους. Η χρησιμοποίηση ενός ενδιάμεσου λογισμικού όπως είναι το Enterprise Service Bus μπορεί να λειτουργήσει σωτήρια σε τέτοιες περιπτώσεις. Η αξιοποίηση των αντίστοιχων πλατφορμών ανοικτού κώδικα μπορούν να οδηγήσουν στην ολοκληρωτική επιχειρηματική ενοποίηση.
description: The increased business needs led to the adoption of several IT systems to better manage their business operations. In order to be sustainable in competition, there is a need for full use of these systems. Businesses making these different software applications and services collaborate, produce unified business functionality and added value to existing applications. They also have the ability to offer faster and more quality services to their customers. Using an intermediate software such as the Enterprise Service Bus can work safer in such cases. Utilizing the respective open source platforms can lead to total enterprise integration.
title: A robust two-level incomplete factorization for (Navier-)Stokes saddle point matrices
Creators: name: Wubs, FW
name: Thies, J
Publisher: name: Science and Technology Facilities Council
Year: 2010
Subjects: electrical networks
Saddle point problem
F-matrix
contraint preconditioning
incompressible (Navier-)Stokes equations
grid-independent convergence
indefinite matrix
incomplete factorization
Arakawa C-grid

description: We present a new hybrid direct/iterative approach to the solution of a special class of saddle point matrices arising from the discretization of the steady incompressible Navier-Stokes equations on an Arakawa C-grid. The two-level method introduced here has the following properties: (i) it is very robust, even close to the point where the solution becomes unstable; (ii) a single parameter controls fill and convergence, making the method straightforward to use; (iii) the convergence rate is independent of the number of unknowns; (iv) it can be implemented on distributed memory machines in a natural way; (v) the matrix on the second level has the same structure and numerical properties as the original problem, so the method can be applied recursively; (vi) the iteration takes place in the divergence-free space, so the method qualifies as a ?constraint preconditioner?; (vii) the approach can also be applied to Poisson problems. This work is also relevant for problems in which similar saddle point matrices occur, for instance when simulating electrical networks, where one has to satisfy Kirchhoff?s conservation law for currents.