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Search for flavor-changing neutral current interactions of the top quark and the Higgs boson decaying to a bottom quark-antiquark pair at √s = 13 TeV
No full textA search for flavor-changing neutral current interactions of the top quark (t) and the Higgs boson (H) is presented. The search is based on a data sample corresponding to an integrated luminosity of 137 fb−1 recorded by the CMS experiment at the LHC in proton-proton collisions at s = 13 TeV. Events containing exactly one lepton (muon or electron) and at least three jets, among which at least two are identified as originating from the hadronization of a bottom quark, are analyzed. A set of deep neural networks is used for kinematic event reconstruction, while boosted decision trees distinguish the signal from the background events. No significant excess over the background predictions is observed, and upper limits on the signal production cross sections are extracted. These limits are interpreted in terms of top quark decay branching fractions (B) to the Higgs boson and an up (u) or a charm quark (c). Assuming one nonvanishing extra coupling at a time, the observed (expected) upper limits at 95% confidence level are B(t → Hu) < 0.079 (0.11)% and B(t → Hc) < 0.094 (0.086)%. [Figure not available: see fulltext.].Publisher versio
Bit-error-rate performance of an underwater wireless optical link under misalignment and turbulence effects
No full textUnderwater wireless optical communication (UWOC) links are highly susceptible to the degrading effects of oceanic turbulence and beam misalignment. In this paper, considering a silicon photo-multiplier at the receiver, we evaluate the link average bit-error rate (BER) performance, where an analytical expression is derived for its calculation, validated further by means of numerical simulations. We further investigate the impact of different system parameters on the link average BER.Alex Ekwueme Federal University Ndufu ; Alex Ekwueme Federal University Ndufu-Alik
Computational investigations of Bio-MOF membranes for uremic toxin separation
No full textDeveloping new and efficient methods as an alternative to hemodialysis is important due to the challenges associated with poor efficiency of membranes and long dialysis sessions. Recently, metal organic frameworks (MOFs) have attracted interest in the membrane community due to their tunable physical and chemical properties. However, their potential in uremic toxin separations is still unknown and it is not practical to test each synthesized MOF for uremic toxin separations. The main objective of this study is to computationally assess membrane-based uremic toxin separation performances of 60 bio-compatible MOFs (bio-MOFs). Combining grand canonical Monte Carlo (GCMC) and equilibrium molecular dynamics (EMD) simulations, we predicted urea, creatinine, and water permeabilities of bio-MOFs and their membrane selectivities for urea/water and creatinine/water separations. Results showed that OREZES, a carboxylate-based MOF exhibited the highest membrane selectivity (347.94) for urea/water separation whereas BEPPIX, an amino-based MOF gave the highest creatinine/water selectivity (1.5 × 105) at infinite dilution and 310 K. Guest-guest and host–guest interaction energies for uremic toxins were also computed during EMD simulations and van der Waals interactions were found to be much stronger than the coulombic interactions. We finally examined the effect of MOF's flexibility on the predicted membrane performance and membrane selectivities of bio-MOFs for urea/water separation significantly enhanced when the structural flexibility was considered in simulations. Our results will be a guide for further studies to design novel bio-MOF membranes for uremic toxin separations
Reappraisal, social support, and parental burnout
No full textObjectives: Parental burnout is a prevalent condition that affects parents' functioning and health. While various protective factors have been examined, little is known about their interplay. In the current study, we examined the joint effect of two protective factors against parental burnout (one external—social support and one internal—cognitive reappraisal). We were specifically interested in whether the presence of one factor could compensate for the lack of the other. Methods: To address this question, 1835 participants were drawn from five countries: United States, Poland, Peru, Turkey and Belgium. Results: Results suggested that both social support and cognitive reappraisal were associated with lower parental burnout. An interaction was also found between the resource factors, such that the presence of cognitive reappraisal compensated for the absence of social support. Conclusions: These findings point to ways in which parental burnout could be reduced, especially in situations where social support is not easily available.Australian Research Council ; Fédération Wallonie-Bruxelle
Embracing vulnerability in writing migrant lives
No full textIn this paper, an anthropologist and a life writer examine the implications of an ethical and political practice of vulnerability with regards to writing migrant lives. Drawing on research with migrants in Turkey and Australia, we argue that it is useful to use vulnerable methodologies, vulnerable relationships and vulnerable writing
Culture in physical activity: The contribution of basic psychological needs and goal orientation
No full textNumerous variables affect motivation in physical activity (PA) with culture being an understudied variable. Self-determination theory’s basic psychological needs (BPN) includes a combination of autonomy, competence, and relatedness in PA; however, cultural definitions pit autonomy and relatedness against each other. Thus, this study aims to investigate the moderating role of culture on relationships between BPN, goal orientations (ego, task) for PA, and PA behavior. A survey was implemented to 168 participants (109 females, 59 males; 92 Turks, 76 Americans) investigating students’ self-construal type, their basic psychological needs in exercise (BPNES), PA levels (Godin Leisure-Time Exercise Questionnaire/GLTEQ), and goal orientation types (Task and Ego Orientation in Sport Questionnaire/TEOSQ). Turks (n = 92) and Americans (n = 76) demonstrated distinct cultural differences in terms of the study variables. American students were more autonomous, task-oriented, and physically active than Turkish students. Results from the multi-group path analysis showed that there was a moderating role of culture between predictors (i.e., BPN Autonomy, BPN Relatedness, BPN Competence, Ego Orientation, and Task Orientation) and Physical Activity. Such that, the paths from predictors (i.e., BPNT Autonomy, BPNT Relatedness, BPNT Competence, Ego Orientation, and Task Orientation) to PA was not significant in Turkish cultural context. Results suggest that culturally tailored approaches to PA interventions are critical in supporting motivation for physical activity and further research is needed to explore different culturally relevant motivational drivers for PA among adults.Publisher versio
Cryptographic security concerns on timestamp sharing via a public channel in quantum-key-distribution systems
No full textQuantum-key-distribution protocols are known to be vulnerable against a side channel attack that exploits the time difference in detectors' responses used to obtain key bits. The recommended solution against this timing side channel attack is to use a large time bin width instead of high-resolution timing information. A common notion is that using a large bin width reduces the resolution of detectors' responses, hence supposedly minimizes the information leakage to an eavesdropper. We challenge this conventional wisdom and demonstrate that increasing the bin width does not monotonically reduce the mutual information between the key bits and the eavesdropper's observation of detectors' responses. Instead of randomly increasing the bin width, it should be carefully chosen because the mutual information fluctuates with respect to the bin width. We also examine the effect of full width half maximums (FWHMs) of the detectors' responses on the mutual information and show that decreasing the FWHM increases the mutual information. Lastly, the start time of binning is also shown to be important in the binning process and the mutual information fluctuates periodically with respect to it.TÜBİTA
Search for heavy resonances decaying to ZZ or ZW and axion-like particles mediating nonresonant ZZ or ZH production at s√ = 13 TeV
No full textA search has been performed for heavy resonances decaying to ZZ or ZW and for axion-like particles (ALPs) mediating nonresonant ZZ or ZH production, in final states with two charged leptons (ℓ = e, μ) produced by the decay of a Z boson, and two quarks produced by the decay of a Z, W, or Higgs boson H. The analysis is sensitive to resonances with masses in the range 450 to 2000 GeV. Two categories are defined corresponding to the merged or resolved reconstruction of the hadronically decaying boson. The search is based on data collected during 2016–2018 by the CMS experiment at the LHC in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 138 fb−1. No significant excess is observed in the data above the standard model background expectation. Upper limits on the production cross section of heavy, narrow spin-2 and spin-1 resonances are derived as functions of the resonance mass, and exclusion limits on the production of bulk graviton particles and W′ bosons are calculated in the framework of the warped extra dimensions and heavy vector triplet models, respectively. In addition, upper limits on the ALP-mediated diboson production cross section and ALP couplings to standard model particles are obtained in the framework of linear and chiral effective field theories. These are the first limits on nonresonant ALP-mediated ZZ and ZH production obtained by the LHC experiments.BMBWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, FAPERGS, and FAPESP (Brazil); MES and BNSF (Bulgaria); CERN; CAS, MoST, and NSFC (China); MINCIENCIAS (Colombia); MSES and CSF (Croatia); RIF (Cyprus); SENESCYT (Ecuador); MoER, ERC PUT and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRI (Greece); NKFIA (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); MSIP and NRF (Republic of Korea); MES (Latvia); LAS (Lithuania); MOE and UM (Malaysia); BUAP, CINVESTAV, CONACYT, LNS, SEP, and UASLP-FAI (Mexico); MOS (Montenegro); MBIE (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Dubna); MON, RosAtom, RAS, RFBR, and NRC KI (Russia); MESTD (Serbia); SEIDI, CPAN, PCTI, and FEDER (Spain); MOSTR (Sri Lanka); Swiss Funding Agencies (Switzerland); MST (Taipei); ThEPCenter, IPST, STAR, and NSTDA (Thailand); TUBITAK and TAEK (Turkey); NASU (Ukraine); STFC (United Kingdom); DOE and NSF (U.S.A.). Individuals have received support from the Marie-Curie program and the European Research Council and Horizon 2020 Grant, contract Nos. 675440, 724704, 752730, 758316, 765710, 824093, 884104, and COST Action CA16108 (European Union); the Leventis Foundation; the Alfred P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; the Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); the F.R.S.-FNRS and FWO (Belgium) under the "Excellence of Science -EOS" -be.h project n. 30820817; the Beijing Municipal Science & Technology Commission, No. Z191100007219010; the Ministry of Education, Youth and Sports (MEYS) of the Czech Republic; the Deutsche Forschungsgemeinschaft (DFG), under Germany's Excellence Strategy -EXC 2121 "Quantum Universe" -390833306, and under project number 400140256 -GRK2497; the Lendulet ("Momentum") Program and the Janos Bolyai Research Scholarship of the Hungarian Academy of Sciences, the New National Excellence Program UNKP, the NKFIA research grants 123842, 123959, 124845, 124850, 125105, 128713, 128786, and 129058 (Hungary); the Council of Science and Industrial Research, India; the Latvian Council of Science; the Ministry of Science and Higher Education and the National Science Center, contracts Opus 2014/15/B/ST2/03998 and 2015/19/B/ST2/02861 (Poland); the Fundacao para a Ciencia e a Tecnologia, grant CEECIND/01334/2018 (Portugal); the National Priorities Research Program by Qatar National Research Fund; the Ministry of Science and Higher Education, projects no.14.W03.31.0026 and no. FSWW-2020-0008, and the Russian Foundation for Basic Research, project No.
19-42-703014 (Russia); the Programa Estatal de Fomento de la Investigacion Cientifica y Tecnica de Excelencia Maria de Maeztu, grant MDM-2015-0509 and the Programa Severo Ochoa del Principado de Asturias; the Stavros Niarchos Foundation (Greece); the Rachadapisek Sompot Fund for Postdoctoral Fellowship, Chulalongkorn University and the Chulalongkorn Academic into Its 2nd Century Project Advancement Project (Thailand); the Kavli Foundation; the Nvidia Corporation; the SuperMicro Corporation; the Welch Foundation, contract C-1845; and the Weston Havens Foundation (U.S.A.).Publisher versio
Öğrenme güçlüğü olan çocukların Covid-19 pandemisine dair deneyimleri
No full textThe purpose of the current study was to examine the indirect effect of resilience and certain coping strategies (seeking social problem-solving solving coping, avoidance) on associations between emerging adults’ intolerance of uncertainty, future career anxiety, and test anxiety in the COVID-19 pandemic. The sample consisted of 481 (357 female, 121 male, and 3 non-binary) emerging adults aged between 18 and 30 (Mage = 22.03, SD= 2.62). Participants completed the study questionnaire online. The indirect effects of resilience and coping strategies on association between intolerance of uncertainty, future career anxiety, and test anxiety were tested. Findings showed that intolerance of uncertainty was positively, resilience was negatively associated with future career anxiety and test anxiety. Moreover, problem-focused coping was positively associated with future career anxiety. Additionally, results showed that intolerance of uncertainty was indirectly linked with future career anxiety and test anxiety via resilience. Also, intolerance of uncertainty was indirectly linked with future career anxiety via problem-focused coping. Findings of the current study are discussed considering limitations and future directions.Mevcut çalışmanın amacı, COVID-19 pandemisi sırasında genç yetişkinlerin sahip olduğu psikolojik direncin ve başa çıkma stratejilerinin (sosyal destek arama, problem çözme, kaçınma), belirsizliğe karşı tahammülsüzlük, ileriye yönelik kariyer kaygısı ve sınav kaygısı üzerindeki dolaylı etkisini incelemektir. Örneklem 18-30 yaşları arasında (Ort = 22.03, S = 2.62) toplam 481 genç yetişkinden oluşmaktadır (357 kadın, 121 erkek ve 3 diğer). Katılımcılar, ortalama 15 dakika süren çevrimiçi araştırma anketini internet üzerinden doldurdurmuştur. Yol analizi, belirsizliğe karşı tahammülsüzlükle, ileriye yönelik kariyer kaygısı ve sınav kaygısı arasında olumlu bir bağıntı olduğunu göstermiştir. Problem odaklı başa çıkma yöntemiyle, ileriye yönelik kariyer kaygısı arasında da olumlu bir bağıntı bulunmuştur. Ayrıca, psikolojik dirençle, ileriye yönelik kariyer kaygısı ve sınav kaygısı arasında olumsuz bir bağıntı olduğu görülmüştür. Bunlara ek olarak, belirsizliğe karşı tahammülsüzlüğün psikolojik direnç düzeyi aracılığı ile dolaylı olarak da kariyer kaygısı ve sınav kaygısı ile bağıntılı olduğu görülmüştür. Belirsizliğe karşı tahammülsüzlüğün problem odaklı başa çıkma düzeyi aracılığı ile dolaylı olarak, ileriye yönelik kariyer kaygısı ile bağınlı olduğu bulunmuştur. Bulgular, mevcut çalışmanın sınırlılıkları ve gelecekteki çalışmaların hangi unsurlara dikkat etmesi esas alınarak tartışılmıştır
Studying children's manipulative gestures in spatial puzzle play with VR hand tracking: Analysis of goal-directed actions
No full textThis paper presents insights about children's manipulative gestures in a spatial puzzle play (i.e. tangram) in both real and virtual environments. We present our initial work with 11 children (aged between 7 and 14) and preliminary results based on a qualitative analysis of children's goal-directed actions as one dimension of gestural input. Based on our early results, we list a set of goal-directed actions as a first stage for developing a manipulative gestural taxonomy. For a more comprehensive view, we suggest a further in-depth investigation of these actions combined with hand and finger kinematics, and outline a number of paths for future research