bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring Realistic Nanohertz Gravitational-wave Backgrounds
Authors: Bécsy Bence , Cornish Neil J. , Kelley Luke Zoltan
Published: December 2022

Hundreds of millions of supermassive black hole binaries are expected to contribute to the gravitational-wave signal in the nanohertz frequency band. Their signal is often approximated either as an isotropic Gaussian stochastic background with a power-law spectrum or as an individual source corresponding to the brightest binary. In reality, the signal is best described as a combination of a stochastic background and a few of the brightest binaries modeled individually. We present a method that uses this approach to efficiently create realistic pulsar timing array data sets using synthetic catalogs of binaries based on the Illustris cosmological hydrodynamic simulation. We explore three different properties of such realistic backgrounds that could help distinguish them from those formed in the early universe: (i) their characteristic strain spectrum, (ii) their statistical isotropy, and (iii) the variance of their spatial correlations. We also investigate how the presence of confusion noise from a stochastic background affects detection prospects of individual binaries. We calculate signal-to-noise ratios of the brightest binaries in different realizations for a simulated pulsar timing array based on the NANOGrav 12.5 yr data set extended to a time span of 15 yr. We find that ∼6% of the realizations produce systems with signal-to-noise ratios larger than 5, suggesting that individual systems might soon be detected (the fraction increases to ∼41% at 20 yr). These can be taken as a pessimistic prediction for the upcoming NANOGrav 15 yr data set, since it does not include the effect of potentially improved timing solutions and newly added pulsars.
LYRA. III. The Smallest Reionization Survivors
Authors: Gutcke Thales A. , Pfrommer Christoph , Bryan Greg L. , Pakmor Rüdiger , Springel Volker , Naab Thorsten
Published: December 2022

The dividing line between galaxies that are quenched by reionization (“relics”) and galaxies that survive reionization (i.e., continue forming stars) is commonly discussed in terms of a halo mass threshold. We probe this threshold in a physically more complete and accurate way than has been possible to date, using five extremely high resolution (M
target = 4 M
⊙) cosmological zoom-in simulations of dwarf galaxies within the halo mass range (1–4) × 109
M
⊙. The employed LYRA simulation model features resolved interstellar medium physics and individual, resolved supernova explosions. Interestingly, two out of five of the simulated dwarf galaxies lie close to the threshold mass but are neither full reionization relics nor full reionization survivors. These galaxies initially quench at the time of reionization but merely remain quiescent for ∼500 Myr. At z ∼ 5 they recommence star formation in a synchronous way and remain star-forming until the present day. The parallel timing indicates consistent sound-crossing and cooling times between the halos. While the star formation histories we find are diverse, we show that they are directly related to the ability of a given halo to retain and cool gas. Whereas the latter is most strongly dependent on the mass (or virial temperature) of the host halo at the time of reionization, it also depends on its growth history, the UV background (and its decrease at late times), and the amount of metals retained within the halo.
Numerical Modeling of Energetic Electron Acceleration, Transport, and Emission in Solar Flares: Connecting Loop-top and Footpoint Hard X-Ray Sources
Authors: Kong Xiangliang , Chen Bin , Guo Fan , Shen Chengcai , Li Xiaocan , Ye Jing , Zhao Lulu , Jiang Zelong , Yu Sijie , Chen Yao , Giacalone Joe
Published: December 2022

The acceleration and transport of energetic electrons during solar flares is one of the outstanding topics in solar physics. Recent X-ray and radio imaging and spectroscopy observations have provided diagnostics of the distribution of nonthermal electrons and suggested that, in certain flare events, electrons are primarily accelerated in the loop top and likely experience trapping and/or scattering effects. By combining the focused particle transport equation with magnetohydrodynamic (MHD) simulations of solar flares, we present a macroscopic particle model that naturally incorporates electron acceleration and transport. Our simulation results indicate that physical processes such as turbulent pitch-angle scattering can have important impacts on both electron acceleration in the loop top and transport in the flare loop, and their influences are highly energy-dependent. A spatial-dependent turbulent scattering with enhancement in the loop top can enable both efficient electron acceleration to high energies and transport of abundant electrons to the footpoints. We further generate spatially resolved synthetic hard X-ray (HXR) emission images and spectra, revealing both the loop-top and footpoint HXR sources. Similar to the observations, we show that the footpoint HXR sources are brighter and harder than the loop-top HXR source. We suggest that the macroscopic particle model provides new insights into understanding the connection between the observed loop-top and footpoint nonthermal emission sources by combining the particle model with dynamically evolving MHD simulations of solar flares.
AFM Force Measurements to Explore Grain Contacts with Relevance for Planetary Materials
Authors: Jardine Keanna , Dove Adrienne , Tetard Laurene
Published: December 2022

Most small asteroids are defined as “rubble piles” or bodies with zero tensile strength and large bulk porosity. The cohesive forces that hold them together act at the grain scale, and their magnitude is often estimated from similar materials when used in simulations. Improving the accuracy of predictions of asteroid strengths requires suitable laboratory measurements of relevant materials, as well as increasing the availability of materials from sample return. Atomic force microscopy (AFM) is well suited for force measurements relative to particle–particle interactions. In this work, we use AFM force measurements to evaluate the cohesive forces that act between micron-sized grains. We investigate the effect of the sizes of the interacting grains of JSC-1 lunar simulant using three sample sizes (<45, 75–125, and 125–250 μm) and three spherical AFM tip diameters (2 μm, 15 μm, and 45 μm). In all cases, adhesion forces were larger at ambient relative humidity (RH), where the water layer on the surface of the grains is more prominent, creating a larger meniscus between the tip and the grain upon contact. We observed weaker adhesion with larger grain/tip size, which can be attributed to the changing contact area between the samples and the tips. We expect that our approach will pave the way to a better understanding of regolith surface properties such as adhesion and cohesion and provide suitable input for models that can be used to predict the evolution of asteroids and their particle behaviors.
Spectroscopic Mapping of Io’s Surface with HST/STIS: SO2 Frost, Sulfur Allotropes, and Large-scale Compositional Patterns
Authors: Trumbo Samantha K. , Davis M. Ryleigh , Cassese Benjamin , Brown Michael E.
Published: December 2022

Io’s intense volcanic activity results in one of the most colorful surfaces in the solar system. Ultraviolet and visible-wavelength observations of Io are critical to uncovering the chemistry behind its volcanic hues. Here, we present global, spatially resolved ultraviolet-visible spectra of Io from the Space Telescope Imaging Spectrograph on the Hubble Space Telescope, which bridge the gap between previous highly resolved imagery and disk-integrated spectroscopy, to provide an unprecedented combination of spatial and spectral detail. We use this comprehensive data set to investigate spectral endmembers, map observed spectral features associated with SO2 frost and other sulfur species, and explore possible compositions in the context of Io surface processes. In agreement with past observations, our results are consistent with extensive equatorial SO2 frost deposits that are stable over multidecade timescales, widespread sulfur-rich plains surrounding the SO2 deposits, and the enrichment of Pele’s pyroclastic ring and the high-latitude regions in metastable short-chain sulfur allotropes.
High Rates of Symptoms of Major Depressive Disorder and Panic Disorder in a Canadian Sample of Adolescents With Juvenile Idiopathic Arthritis
Authors: Li Lydia , Merchant Mehveen , Gordon Shelina , Lang Bianca , Ramsey Suzanne , Huber Adam M. , Gillespie Joanne , Lovas David , Stringer Elizabeth
Published: December 2022

Objective

We aimed to evaluate the rate of depressive and/or anxiety symptoms in adolescents with juvenile idiopathic arthritis (JIA) and to explore the association with demographic and disease activity measures.

Methods

Depressive and anxiety symptoms were assessed in adolescents with JIA aged 12 to 18 years at a Canadian tertiary care hospital, using the Revised Child Anxiety and Depression Scale (RCADS). The RCADS includes 6 subscales: separation anxiety, social phobia, generalized anxiety, panic disorder, obsessive-compulsive, and major depressive disorder. Scores above clinical threshold on the RCADS subscales indicate that an individual’s responses reflect symptoms similar to those diagnosed with the corresponding mental health disorder. Fisher exact test and Mann-WhitneyUtest were used to compare demographic and disease-related variables between participants who scored above and below clinical threshold on each of the subscales.

Results

There were 32/80 (40%) of participants who scored above clinical threshold on at least 1 subscale. Scores above clinical threshold were most frequent for major depressive disorder (23.8%) and panic disorder (22.5%) subscales. Social phobia and separation anxiety followed with 16.3% and 13.8%, respectively. Females were more likely to have scores above clinical threshold on the panic disorder subscale. Participants with higher self-reported disease activity were more likely to have scores above clinical threshold for all anxiety subscales except separation anxiety.

Conclusion

We report high rates of symptoms of depression and anxiety (panic in particular) in adolescents with JIA. This highlights the ongoing need for mental health screening protocols and services. The relationships between concomitant mental health disorders, disease activity, and patient-reported outcomes requires further research.
Lower Frequency of Comorbidities Prior to Onset of Giant Cell Arteritis: A Population-Based Study
Authors: Elfishawi Mohanad , Rakholiya Jigisha , Gunderson Tina M. , Achenbach Sara J. , Crowson Cynthia S. , Matteson Eric L. , Turesson Carl , Wadström Karin , Weyand Cornelia , Koster Matthew J. , Warrington Kenneth J.
Published: December 2022

Objective

To assess the frequency of comorbidities and metabolic risk factors at and prior to giant cell arteritis (GCA) diagnosis.

Methods

This is a retrospective case control study of patients with incident GCA between January 1, 2000, and December 31, 2019, in Olmsted County, Minnesota. Two age- and sex-matched controls were identified, and each assigned an index date corresponding to an incidence date of GCA. Medical records were manually abstracted for comorbidities and laboratory data at incidence date, 5 years, and 10 years prior to incidence date. Twenty-five chronic conditions using International Classification of Diseases, 9th revision, diagnosis codes were also studied at incidence date and 5 years prior to incidence date.

Results

One hundred and twenty-nine patients with GCA (74% female) and 253 controls were identified. At incidence date, the prevalence of diabetes mellitus (DM) was lower among patients with GCA (5% vs 17%;P= 0.001). At 5 years prior to incidence date, patients were less likely to have DM (2% vs 13%;P< 0.001) and hypertension (27% vs 45%;P= 0.002) and had a lower mean number (SD) of comorbidities (0.7 [1.0] vs 1.3 [1.4];P< 0.001) compared to controls. Moreover, patients had significantly lower median fasting blood glucose (FBG; 96 mg/dL vs 104 mg/dL;P< 0.001) and BMI (25.8 vs 27.7;P= 0.02) compared to controls. Multivariable logistic regression analysis revealed negative associations for FBG with GCA at 5 and 10 years prior to diagnosis/index date.

Conclusion

DM prevalence and median FBG and BMI were lower in patients with GCA up to 5 years prior to diagnosis, suggesting that metabolic factors influence the risk of GCA.
Real-World Retention and Clinical Effectiveness of Secukinumab for Psoriatic Arthritis: Results From the Canadian Spondyloarthritis Research Network
Authors: Gladman Dafna D. , Choquette Denis , Khraishi Majed , Inman Robert D. , Hussein Shamiza , Neish Drew , Leclerc Patrick
Published: December 2022

Objective

Psoriatic arthritis (PsA) is an immune-mediated disease characterized by pain, stiffness, and swelling of peripheral joints, with an estimated prevalence in Canada of 0.45%. Treatment aims to minimize disease activity, reduce progression of damage, and improve quality of life. Secukinumab (SEC) is a biologic disease-modifying antirheumatic drug (bDMARD) that has demonstrated efficacy and safety for PsA in clinical trials; however, there is limited real-world evidence on its use in Canada. The objective of this study was to use the Canadian Spondyloarthritis (CanSpA) Research Network to describe real-world retention and effectiveness of SEC among Canadian patients with PsA.

Methods

This was an observational cohort study of Canadian patients with PsA, 18 to 65 years of age, who attended a clinic of the CanSpA network and received treatment with SEC. Patients were indexed on the date they first initiated SEC. Retention was assessed at 12 months postindex. Clinical effectiveness was measured as the proportion of patients in remission and change in disease activity from baseline to 12 months using several clinical indices.

Results

In total, 213 patients were included. Overall retention was estimated at 73.6% at 12 months (81.8% for bDMARD- or targeted synthetic DMARD-naïve patients). Out of 110 patients, 17 (15.5%) were in remission based on the Disease Activity Index in Psoriatic Arthritis in 28 joints, and 10 out of 70 patients (14.3%) were in remission based on the Psoriatic Arthritis Disease Activity Score at 12 months. The Psoriasis Area and Severity Index improved by 65.8%; the tender joint count in 68 joints and the swollen joint count in 66 joints improved by 65.5% and 73.7%, respectively.

Conclusion

This is the first nationwide study that we know of to describe real-world use of SEC in Canada for PsA, and the results support its effectiveness in a Canadian real-world setting. The CanSpA network represents a unique opportunity to build and improve the real-world evidence base for SpA treatment in Canada.
Harcèlement : les enfants « s’auteurisent » à en parler
Authors: Touil Ahmed Nordine
Published: December 2022

Lorsque des travailleurs sociaux et des professionnels de l’éducation nationale permettent à des enfants et des adolescents de sensibiliser leurs pairs aux questions liées au harcèlement, cela produit une tentative des plus singulières. Alliant recherche, théâtre-image et intelligence collective, cette expérience se mue en terrain propice à la recherche, pour un formateur-chercheur embarqué dans ce projet. Une lecture et une analyse ethnographique en soulignent le cheminement et la pertinence.
Mains « diaboliques » !
Authors: Rosset Pierre
Published: December 2022

Un triste fait divers réactive chez l’auteur un vécu lointain d’écolier dans lequel il subissait en silence les sanctions violentes et répétées de certains de ses enseignants en s’enfonçant dans la « cancritude ».
Panser et penser la co-construction de la prise en charge
Authors: Fressoz Xavier
Published: December 2022

Trop souvent dans les services, les éducateurs s’interrogent sur la façon de placer l’usager au centre de sa prise en charge. Le besoin semble de nature méthodologique. Aussi, cet article constitue une sorte d’éloge de la pédagogie en spirale pour panser et penser la co-construction de la prise en charge. Prenant appui sur l’illustration concrète d’une activité pêche, il tend à rendre accessible cette pratique qui appréhende l’usager comme sujet et pousse le professionnel à structurer sa capacité d’écoute et de propositions éducatives loin des positionnements paternalistes ou strictement autoritaires.
Trois poèmes
Authors: Bouvier Agnès
Published: December 2022

Comment « faire son deuil »…. je dirais plutôt comment apaiser la douleur de la perte. Écrire m’a permis de garder des portes ouvertes et d’exprimer viscéralement mes sensations face à l’intolérable. Depuis, régulièrement, je pose des mots que je mets en musique, ceux-ci évoluent avec le temps, le deuil nous bouleverse et nous oblige à vivre autrement.
Réenchanter les soins palliatifs… et la médecine ?
Authors: Rochas Bruno
Published: December 2022

Même si les soins palliatifs s’adressent à des patients à un moment très particulier et dramatique de leur vie, leurs valeurs sont universelles et portées par les fondements même de la médecine. Écouter celui qui souffre pour mieux le comprendre, mobiliser les ressources disponibles de façon proportionnée et personnalisée, s’appuyer sur les regards de tous les acteurs mobilisés pour penser ensemble et faire preuve de créativité.
Formules parenthétiques en dire et leur fonctionnement discursif dans les communications scientifiques orales
Authors: Lee Chaeyoung
Published: December 2022

Cet article porte sur les formules parenthétiques construites avec le verbe dire et leurs fonctions dans le discours scientifique oral. Dans le cadre d’une étude plus large sur la phraséologie dans le discours scientifique oral, notre but est de démontrer la particularité du genre des communications scientifiques orales en tant que genre discursif propre, plus particulièrement par une comparaison avec le registre d’interactions en entretien. Les résultats montrent que le genre de communications scientifiques orales se manifeste par une distribution spécifique des formules en dire , où certaines fonctions sont surreprésentées, et qu’il apparaît distinct sur ce point d’autres registres oraux.
Une reconsidération du discours rapporté en langue parlée avec être là , faire ( à quelqu’un ) et se dire
Authors: Fiedler Sophia
Published: December 2022

Cet article étudie le discours rapporté en français parlé à partir de trois introducteurs : être là , faire ( à quelqu’un ) et se dire . Ces clauses « introduisent » des citations de formats divers : sons, clauses complètes et/ou mouvements du corps. Les recherches pionnières sur la langue parlée ne s’accordent pas sur le statut syntaxique des citations : alors que Blanche-Benveniste (1988) soutient que les citations directes sont grammaticalement « informes », de Cornulier (1978) n’exclut pas qu’elles aient un statut de complément. En examinant 12h d’enregistrements vidéo de conversations quotidiennes, l’article illustrera le fait que l’intégration des mouvements corporels dans une grammaire de la langue parlée peut être utile. L’apport de la linguistique interactionnelle montrera qu’ être là , faire ( à quelqu’un ) et se dire sont fonctionnellement distribués dans l’interaction.
Si vous avez quelqu’un sous la main : les si-indépendantes en tant que format de requête
Authors: Horlacher Anne-Sylvie , Pekarek Doehler Simona
Published: December 2022

Cet article interroge les structures si-indépendantes ( si vous avez quelqu’un sous la main ) fonctionnant en tant que requêtes dans un corpus d’appels d’urgence à la police. Sur le plan grammatical, ces structures peuvent être rapprochées de conditionnelles du type [ si-X , (alors) Y]) dont la clause principale n’est pas produite ; elles relèvent ainsi du phénomène de l’insubordination. L’analyse se concentre sur la dimension fonctionnelle des si-indépendantes , en montrant qu’à travers la formulation en si , le citoyen indexe sa propre autorité déontique réduite et donne à l’opérateur de la centrale téléphonique toute la latitude possible pour décliner la requête, celui-ci pouvant justement nier l’existence des conditions sine qua non évoquées dans la structure [ si-X ]. L’étude démontre en quoi une approche interactionnelle permet de mieux comprendre les motivations fonctionnelles des structures dites insubordonnées.
Les relatives en où en français parlé : des plus canoniques aux plus atypiques
Authors: Sabio Fréderic , Roubaud Marie-Noëlle
Published: December 2022

L’article propose un bilan sur les relatives en où en français parlé contemporain, fondé sur la description de 1 373 exemples. À côté des relatives à valeur locative largement représentées, certaines occurrences sont plus difficiles à analyser : dans celles-ci, le lien grammatical entre le SN et le verbe de la relative est complexe – voire impossible – à établir. Nous proposerons de considérer que ces structures atypiques instaurent une relation discursive – plutôt que syntaxique – entre le SN et la partie subséquente, pouvant être décrite sur la base de certaines valeurs sémantiques telles que la caractérisation, la spécification ou la définition.
L’Information géographique en contexte (2) : vers un nouveau modèle (1968-1995)
Authors: Retaillé Denis
Published: December 2022

Ce second texte examine l’évolution de L’Information géographique jusqu’à sa mutation, de la fin des années 1960 à son format actuel qui paraît en 2000. Après que de nouveaux contextes scientifique et pédagogique se sont dessinés à la fin des années 1960, et après une décennie 1970 incertaine, un tournant didactique a marqué le profil éditorial au milieu des années 1980, en réponse à une « crise » en deux temps qui touche à la destination scolaire de la discipline en 1975-1977 puis en 1989, conduisant au choix du format livre, mieux adapté à la contribution critique de la Revue.
Circulation des modèles urbains et promotion de la démocratie. La diffusion du « modèle Barcelone » dans les « pays en développement » (années 1970-années 1990)
Authors: Ripoll Samuel
Published: December 2022

L’analyse des circulations transnationales des « modèles » urbains est au cœur de débats qui, dans les études urbaines, interrogent les liens entre ville et mondialisation. Les recherches se proposent en particulier de mettre à jour les projets politiques qui sous-tendent l’accès de telle ville ou telle politique publique au rang de « bonne pratique » internationale, inscrivant fréquemment la mobilité des politiques urbaines dans une logique de diffusion généralisée du néolibéralisme. En s’inspirant d’une démarche postcoloniale, cet article mobilise la science politique et les études urbaines afin d’explorer une autre hypothèse : la circulation « Nord-Sud » des modèles s’appuie en partie sur un projet de « promotion de la démocratie ». Il s’intéresse à la ville de Barcelone qui, dans les années 1990, s’impose comme une référence mondiale de régénération urbaine, portée par des acteurs locaux qui ont fait de l’urbanisme le cœur de la construction démocratique au lendemain de la dictature franquiste. L’article propose une sociohistoire de l’entreprise active, portée par des élites barcelonaises, de formulation et de promotion internationale de leur expérience auprès des villes dites « en développement », à une époque où les espoirs de généralisation de la démocratie « à l’occidentale » sont à leur apogée.
De la mise en couple à la première naissance. Le rôle de l’âge à la première cohabitation dans l’entrée en maternité et en paternité
Authors: Compans Marie-Caroline , Beaujouan Éva
Published: December 2022

La formation du couple et la première naissance sont des événements étroitement liés, mais les logiques sociales, dont l’âge à la mise en couple peut être le reflet, sont peu discutées. À partir de l’enquête Étude des parcours individuels et conjugaux (Épic, Ined-Insee, 2013-2014), cet article examine le rôle de l’âge à la première cohabitation sur la survenue d’une première naissance et son calendrier, en tenant compte des caractéristiques des personnes et des unions formées entre 17 et 40 ans. Les hommes et les femmes ont un enfant plus rapidement lorsque la première union est formée à partir de 32 ans. Malgré des naissances plus rapides pour ceux devenant parents, les individus les plus tardifs à la mise en couple sont, en fin de vie reproductive, plus nombreux à rester inféconds que ceux entrés en union plus tôt. Ces résultats restent significatifs compte tenu de la situation d’emploi à la mise en couple, du statut marital et des caractéristiques des partenaires. Outre des aspects biologiques, il est possible que les personnes qui forment une première union à la trentaine soient moins enclines à fonder une famille, ou qu’avoir un enfant paraisse socialement trop tardif.
The impact of the quality of manager feedback on new employees
Authors: Martin Pascal , Hofaidhllaoui Mahrane
Published: December 2022

L’article décrit la relation d’échange leader-membre qui s’établit progressivement entre managers et nouveaux arrivants au cours de la socialisation organisationnelle. Nos questions de recherche : L’objectif de cette recherche est d’étudier si la qualité de la relation que le superviseur est censé établir avec les nouveaux employés favorise leur socialisation au sein de l’organisation pour améliorer leur efficacité au travail ? De plus, comment les nouveaux employés perçoivent-ils la relation que le superviseur est censé établir avec eux ? Pour répondre à ces questions, nous avons mené une recherche qualitative sous forme d’entretiens auprès des managers et des nouveaux collaborateurs durant les premiers mois et années dans l’entreprise. Les résultats montrent à quel point l’engagement des nouveaux employés envers leurs objectifs augmente avec la fourniture d’un feedback de qualité par les managers. Fournir des commentaires réguliers et de qualité permet aux nouvelles recrues de comprendre leur statut actuel par rapport à la réalisation des objectifs, augmentant ainsi leur engagement. Cette recherche exploratoire nous permet de constater que la qualité des retours des managers semble être un élément majeur de la relation LMX qui renforce le processus d’adaptation des nouveaux arrivants pour atteindre leurs objectifs professionnels et vivre une meilleure intégration. Cependant, cette recherche présente certaines limites telles que la taille de l’échantillon qui ne permet pas de généraliser les résultats. De nouveaux protocoles pourraient inclure un échantillon de plus grande taille afin d’évaluer les résultats à l’aide d’échelles quantitatives.
Les effets du télétravail sur l’engagement et la performance adaptative des salariés : une mise en perspective des théories des comportements organisationnels en situation de déspatialisation
Authors: Heimburger Clémence
Published: December 2022

Le télétravail altère notre rapport au cadre traditionnel du travail en termes de temps, de lieu et d’action, nous interrogeant sur les conséquences comportementales pour les organisations : comment maintenir l’engagement des salariés en télétravail ? Comment appréhender la performance à distance ? Deux questions majeures que se posent les organisations dans un contexte d’activité déspatialisée et dont l’intérêt se justifie d’autant plus dans un contexte professionnel sensible, postpandémie. En nous inscrivant dans une démarche transactionnelle qui appréhende le travail et son organisation comme sources de satisfaction et de motivation, nous concevons que celles-ci sont influencées par l’évolution de l’environnement de travail et de ses caractéristiques. Cet article théorique a pour objectif de de comprendre les effets du télétravail sur les salariés et leurs comportements organisationnels à travers la satisfaction des besoins fondamentaux liés à l’environnement de travail dans lequel ils évoluent. Pour ce faire, il présente les éléments de littérature portant sur les effets du télétravail en termes d’engagement, de performance et de satisfaction des besoins psychologiques fondamentaux (autonomie, développement, exigences). Mais il permet surtout i) de confronter la spatialité des théories des comportements organisationnels à cette situation de travail, marquée par la déspatialisation, ii) de proposer l’appréciation de la performance à travers l’utilisation du concept de performance adaptative et iii) de montrer les limites des études sur le télétravail par le manque d’outils psychométriques adaptés à l’analyse de cette situation particulière de travail. Enfin, nous inscrivant dans une approche transactionnelle-intégrative-multifactorielle, nous définissons le modèle de notre recherche future et discutons des opportunités à faire évoluer les concepts dans ce domaine.
Natural Hybrid Reinforcement Effect on Mechanical Properties of UPE Composite
Authors: Alrawie Wissam Nubras , Alraziqi Zaynab N. Rasheed , Hamad Qahtan Adnan
Published: December 2022

In this paper the effect of adding natural particles (pomegranate PSP and coconut shell particles CSP ) on unsaturated polyester matrix UPE reinforced with natural sisal fibers studied, some mechanical properties were performed. The natural particle percentage selected to be (5, 10, 15, 20) wt. %, while the percentage of the sisal fibers was constant (2wt. %). The main purpose was to improve UPE properties to be use in structural applications. Chemical treatment was perform on all the reinforcement materials used before the hybrid composite synthesis. Using particles size distribution (PSD) it was found that (2956.9 and 2961.6) nm were the size of PSP and CSP, respectively. Then, samples were prepared in the laboratory at room temperature using Hand-layup technique. Tests as Flexural strength, flexural modulus, impact strength, max shear strength and surface roughness were applied on the composite samples. Results were as follows: a clear improvement in the mechanical properties of the UPE reinforced with sisal fibers. As for the fiber-particle reinforced polyester (UPE) ,the results were an increase in the flexural modulus by 5wt.% when adding coconut particle, while it decreased when adding pomegranate particle at same ratio. As for the flexural strength when the adding particles ratio increases, it decreases in the case of pomegranate particles addition while increases in the coconut particles addition. Interestingly, impact strength value increased at 5wt.% for both particle addition, while for further ratio there was a value reduction. An increase in max shear strength was also found as the highest value was in the pomegranate matrix at 5wt.%, while it was in the coconut matrix at 20wt.%. Finally, that the surface roughness value gradually increases with the increase additive ratio. Also, SEM
Enhancement Mechanical Properties of Polymers Reinforcing by Nano Graphene
Authors: Handoul Karrar A. , Taher Ahmed A.
Published: December 2022

Composite resin is one of the most important materials used in all industrial and medical fields nowadays, but it has many properties and advantages that distinguish it from metals. Many problems appeared previously due to the materials used and to overcome these problems, A composite resin with great physical and mechanical properties and compatibility has been developed. Composite resins are resin filled with high compressive strength, corrosion resistance, light weight, ease of application and high transparency. The aim of this study is to demonstrate the improvement of mechanical properties represented in tensile strength, fatigue life, impact resistance and hardness For polymeric materials such as epoxy after adding nanomaterials (graphene).
Compressive Strength and Expansion Characteristics of Mortar Mixtures Incorporating Chronologically Aged-Basic BOFS Aggregates Blended with GGBFS and Fly Ash
Authors: Kuszhanova Assem , Raiymbek Moldir , Abzal Aliya , Shon Chang Seon , Sandybay Saken , Tukaziban Aizhan , Kim Jong Ryeol
Published: December 2022

During the steelmaking process, many by-products, such as blast-furnace slag (BFS), basic oxygen furnace slag (BOFS), and ladle slag (LS), are generated. Unlike BFS, utilizing BOFS is limited due to its expansive volumetric characteristics by the transformation process of free lime (f-CaO) and free magnesia (f-MgO) to portlandite (Ca(OH)2) and brucite (Mg(OH)2). The natural aging process may help BOFS used as an aggregate in mortar or concrete because harmful elements such as f-CaO and f-MgO could be consumed during this stage. This study evaluated compressive strength and expansion characteristics of mortar mixtures incorporating chronologically aged-BOFS aggregates blended with ground granulated blast furnace slag (GGBFS) and ASTM class F fly ash (FFA). Test results revealed that the longer aged BOFS aggregate, the lower compressive strength, regardless of mixture types. The aging process of BOFS aggregate reduced the expansion of mortar mixtures. Incorporating GGBFS or FFA into mortar mixtures containing BOFS aggregate even more reduced the expansion of the mixture.
The Compatibility Characterization of PMMA/DPET Based Polymer Blend
Authors: Saleem Doaa S. , Alzuhairi Mohammed , Nassir Nassier Abdul Hussain
Published: December 2022

The compatibility of polymers based on the blending of methyl methacrylate (PMMA) and depolymerized polyethylene terephthalate (DPET) was studied in this investigation. Initially, the PET was obtained using the waste bottle before the depolymerization process to get the final product of DPET. Here, the preparation of the polymer blend used was carried out by mixing the two polymers manually. The affinity of the polymers to each other is conducted using Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). The results of FT-IR indicate that some bands were shifted, some of them were decreased, and the others were eliminated by the addition of DPET to PMMA. This behavior can be attributed to interaction and coordination between the PMMA and DPET. Based on DSC analysis, the melting temperatures of PMMA and DPET blends were reduced as compared to pure PMMA, with the exception of the 99/1 (PMMA/DPET) blend. PMMA's surface morphology reveals a rough surface with a micropore structure. The appearance of pure DPET in the SEM image shows a rough surface with diverse shaped and sized particles. Also, the 5/95 (DPET/PMMA) blend doesn't seem to have any visible phase separation. Keywords: Compatibility, polymer blend, PMMA, DPET
Impact of Industry-Specific and Macroeconomic Factors on Non-Performing Loans of Licensed Banks in Sri Lanka
Authors: Damayanthi N. M. M. , Gunawardhana C. S.
Published: December 2022

This study aims to examine the factors affecting to non-performing loans (NPLs) covering 30 licensed banks (LBs) in Sri Lanka. The selected variables affecting to NPLs considered as industry-specific and macroeconomic variables which can easily identify the internal and external influenced to the position of NPLs of LBs. The study covers the data from 2000 to 2019 exploring autoregressive distributed lag model and checking the robustness of the results using Vector Error Correction Model. The test results revealed that both industry-specific and macroeconomic variables significantly influenced on NPLs in LBs in Sri Lanka. Some industry-specific factors such as loan growth of LBs, net operating profits and deposit rates show the significant positive relationship with NPLs. Among the macroeconomic factors, gross domestic product and unemployment rate had a negative effect on NPLs. However, domestic credit and exchange rate included into macroeconomic variables revealed that positive relationship with NPLs in LBs. The study recommends when releasing loans to businesses including micro, small and medium scale enterprises, need more concentrate about both industry specific and macroeconomic factors due to main constraint of a LB is NPL which may increase or decrease at any time. The findings of this study may use for casting and measuring of NPLs in the future scenarios and to take decisions on all financial sector related industries in Sri Lanka. The research recommends further to maintain higher level of provisions for bad loans if high NPLs are observed in the books of accounts in LBs.
Reflection of Environmental Citizenship Behaviour through Domestic Waste Disposal Practices: Examination on Youth in Sri Lanka
Authors: Sachitra V.
Published: December 2022

The comparison of Environmental Citizen Behaviour (ECB) and waste disposal mechanism is relatively unknown among youth. The study explores how ECB reflects through domestic waste disposal practices by analyzing extend of ECB and waste disposal practices among Sri Lankan youth descriptively. A quantitative cross-sectional online survey was adopted to collect data from students in Sri Lankan universities. ECB was measured with a modified version of the eleven-item scale developed. Measurement properties were assessed using confirmatory factor analysis. Descriptive statistics, cross-tabulation analysis and mean comparison analysis were utilized as data analysis techniques. The study operationalized ECB as eco-initiatives, eco-helping and eco-civic engagement. Relative to eco initiative and eco helping, low practice was reported to eco-civic engagement. Presence of low and moderate ECB, the probability of using waste collection arrangement was high. Respondents with higher level of ECB, applicability of composting the waste is relatively high. However, dumping waste outside premises was also high among highest ECB. Compared to individuals with high and low ECB, burning waste was higher for moderate ECB. The findings suggest that there is a certain level of ECB that is necessary for waste disposal method selection, however when the ECB level optimized, it may affect waste disposal negatively. The joint inspiration of ECB and waste disposal is relatively unknown.  In Sri Lanka, which is a developing context, there is a lack of studies about the connection between ECB and waste disposal.
Impact of Entrepreneurial Orientation and Entrepreneurship Education on Entrepreneurial Intention and Internationalization of Engineer-Entrepreneur Start-ups
Authors: Mudalige D. M.
Published: December 2022

While application of entrepreneurship concept is gaining traction in engineering and the entrepreneurship courses embedded in engineering programs increase swiftly, there is a lack of study focusing on how engineering programs enable entrepreneurial experiences in their programmes. The influence of entrepreneurial orientation and entrepreneurship education on achievement entrepreneurial goals of engineers in Sri Lanka remains understudied and uncertain in many circumstances. This necessitates a thorough examination of the mechanisms by which entrepreneurial orientation and education influences entrepreneurial intention. Further, as per international entrepreneurship theory, entrepreneurial intent leads to internationalization intent when facilitated by conducive environment factors. The objective of research is to investigate the influence of entrepreneurial orientation and entrepreneurship education on entrepreneurial intention and internationalization intent of engineer entrepreneurs in Sri Lanka. Three hypotheses related to above links were tested using a validated questionnaire through a survey of 92 engineer-entrepreneurs. The results show that there is a significant positive relationship between entrepreneurial orientation and entrepreneurship education on entrepreneurial intention and internationalization intent of engineer entrepreneurs in Sri Lanka. The variable entrepreneurial intention explained 40% variance of internationalization intention. This research gives valuable inputs and suggestions with respect to entrepreneurship education and promotion of entrepreneurship orientation of engineers in Sri Lanka for policy makers.
Prospective Study of Laparoscopic Management of Appendicitis During the COVID Pandemic in a Single Paediatric Centre
Authors: Dass Dipankar , Hotonu Sesi , McHoney Merrill , Munro Fraser
Published: December 2022

Background:

The coronavirus (COVID-19) pandemic affected the presentation of many conditions. This study analyses and describes the impact of the COVID-19 pandemic on the management of appendicitis in children and the role of laparoscopy.

Materials and Methods:

We performed a prospective (during the pandemic) and retrospective (historic control) review of the management of appendicitis in a tertiary paediatric surgical unit. Preoperative data, operative findings and patient outcomes were compared between groups to identify differences between the study periods and to identify any factors predictive of outcomes.

Results:

Sixty-two patients were identified in the pre-pandemic cohort, 72 in the pandemic cohort. There was no significant difference in patient demographics, length of admission or time between admission and surgery between groups. There was however a significantly longer time to presentation to hospital in the pandemic group. Clinical outcomes were comparable between the two groups, with no difference in the presence of surgical complications or histologically advanced appendicitis between the two groups. Laparoscopic surgery was safely used to manage appendicitis in the pandemic cohort through utilisation of a COVID-19 pathway that included guidance on testing, and use of personal protective equipment (PPE). Conservative management in the pandemic cohort was reserved for patients with appendicitis with the presence of mass formation.

Conclusion:

Despite a delayed presentation to hospital, there was no rise in the incidence of complicated appendicitis, complications of surgery or length of stay during the COVID-19 pandemic. Laparoscopic appendicectomy was also shown to be a safe and effective standard for the management of appendicitis during the pandemic.

Level of Evidence:

III, treatment.
Role of Bioactive Collagen Peptide in the Management of Monoidoacetate Induced Osteoarthritis and its Comparison with Diacerein in Rat Model
Authors: Kant Ravi , Rao Parul , Tank Gyaneshwer , Gupta Rohit
Published: December 2022

Osteoarthritis is the most common joint disorder. Currently, there are no stabilized pharmacological agents capable of retarding the progression or preventing OA. This is a fundamental and important area of current research. Therefore, the present study was to investigate the action of Bioactive Collagen peptide against Monosodium Iodoacetate induced Osteoarthritis in rat models and its comparison with Diacerein. Nine experimental groups were taken. Osteoarthritis was induced by intraarticular injection of Monosodium Iodoacetate (MIA) in knee joints. Bioactive Collagen peptide was given to groups 7, 8 and 9 for 1, 2 and 3 months respectively, then histopathological examination was done. Diacerein was given to groups 4, 5 and 6 for 1, 2 and 3 months respectively followed by histopathological scoring. Significant (P < 0.05) chondroprotection was observed after treatment of Bioactive Collagen peptide when compared with MIA control group as well as Placebo treated group. Significant improvement was also observed when compared with Diacerein treated groups for 1 and 2 monthsIt was concluded that both Bioactive Collagen Peptide and Diacerein are potent chondroprotective agent, but Collagen peptide is far better than Diacerein.
The cytotoxic effects of indoleamine 2, 3-dioxygenase inhibitors on triple negative breast cancer cells upon tumor necrosis factor α stimulation
Authors: Bilir Cemil , Eskiler Gamze Guney , Bilir Filiz
Published: December 2022

Context:

Overexpressed indoleamine 2,3-dioxygenase (IDO) has been observed in many types of cancer and plays an essential role in the tumor microenvironment through immune cells function.

Aims:

In our study, the therapeutic potentials of two different IDO inhibitors (Epacadostat [EPA] and 1-methyl-L-tryptophan [L-1MT]) in triple-negative breast cancer (TNBC) cells were assessed with and without tumor necrosis factor-α (TNF-α) stimulation.

Materials and Methods:

The anticancer activity of EPA and L-1MT alone and in combination with TNF-α was analyzed by WST-1, annexin V, cell cycle analysis, and acridine orange/ethidium bromide staining. In addition, the relationship between IDO1 and programmed death-ligand 1 (PD-L1) expressions in TNBC cells upon treatment with IDO inhibitors was evaluated by reverse transcription–polymerase chain reaction analysis.

Statistical Analysis Used:

SPSS 22.0 was conducted for statistical analysis. The one-way analysis of variance with Tukey’s multiple comparison test was performed for multiple groups. Independent (unpaired) t-test was used for the comparison of two groups.

Results:

EPA and L-1MT alone significantly suppressed the TNBC cell viability through the induction of apoptotic cell death and G0/G1 arrest (P < 0.05). TNF-α alone induced the overexpression of IDO1 and PD-L1 in TNBC cells compared with MCF-10A control cells. However, IDO inhibitors significantly inhibited overexpressed IDO1 mRNA levels. Furthermore, EPA alone and co-treated with TNF-α suppressed the mRNA level of PD-L1 in TNBC cells. Therefore, TNF-α stimulation enhanced the therapeutic effects of IDO inhibitors on TNBC.

Conclusions:

Our findings showed that the efficacy of IDO inhibitors was mediated by pro-inflammatory cytokine. However, different molecular signaling pathways are associated with pro-inflammatory cytokines production, and the expression of IDO1 and PD-L1 calls for further investigations.
The Face Detection / Recognition , Perspective and Obstacles In Robotic: A Review
Authors: Uddin Nafiz Md Imtiaz , Moshayedi Ata , Lan Hong , Shuxin Yang
Published: December 2022

Facial recognition research is one of the different types of research in this world today. In recent years, facial recognition in robots has attracted increased study interest. Robotic platforms now utilize a variety of object detection methods, with face detection being a viable use. Face detection in robotics is a computer technique that recognizes human faces in digital pictures and is used in a range of applications. Different authors have performed their research in different ways on the use of detection systems. This paper aims to give future researchers a better idea of using facial recognition systems in robotics. In this study, we reviewed research by various authors over recent years to facilitate future facial recognition research. In addition, scholars have addressed the topics, how they have done so, and the specifics of their approaches are described. This paper reviewed an overview of hardware implementation and software implementation by various authors. It can automatically focus cameras or count the number of people who have entered a location. Commercial applications of the method include displaying tailored advertisements in response to a recognized face along with the algorithms, functions and architectures used in facial recognition and giving the opinions of various authors mentioned. The comparative analysis of facial recognition and its architecture system is highlighted.