MyMedR

Fulltext In Situ SEM Nanomanipulation and Nanomechanical/Electrical Characterization

Lu Y, Shen Y, Liu X, Ahmad MRB, Chen Y

Scanning, 2017;2017:8016571.

PMID: 29238439 DOI: 10.1155/2017/8016571

An interpretable XGBoost-based approach for Arctic navigation risk assessment

Yao S, Wu Q, Kang Q, Chen YW, Lu Y

Risk Anal, 2024 Feb;44(2):459-476.

The Northern Sea Route (NSR) makes travel between Europe and Asia shorter and quicker than a southern transit via the Strait of Malacca and Suez Canal. It provides greater access to Arctic resources such as oil and gas. As global warming accelerates, melting Arctic ice caps are likely to increase traffic in the NSR and enhance its commercial viability. Due to the harsh Arctic environment imposing threats to the safety of ship navigation, it is necessary to assess Arctic navigation risk to maintain shipping safety. Currently, most studies are focused on the conventional assessment of the risk, which lacks the validation based on actual data. In this study, actual data about Arctic navigation environment and related expert judgments were used to generate a structured data set. Based on the structured data set, extreme gradient boosting (XGBoost) and alternative methods were used to establish models for the assessment of Arctic navigation risk, which were validated using cross-validation. The results show that compared with alternative models, XGBoost models have the best performance in terms of mean absolute errors and root mean squared errors. The XGBoost models can learn and reproduce expert judgments and knowledge for the assessment of Arctic navigation risk. Feature importance (FI) and shapley additive explanations (SHAP) are used to further interpret the relationship between input data and predictions. The application of XGBoost, FI, and SHAP is aimed to improve the safety of Arctic shipping using advanced artificial intelligence techniques. The validated assessment enhances the quality and robustness of assessment.

MenSCs Transplantation Improve the Viability of Injured Endometrial Cells Through Activating PI3K/Akt Pathway

Zhang S, Zhang R, Yin X, Lu Y, Cheng H, Pan Y, et al.

Reprod Sci, 2023 Nov;30(11):3325-3338.

PMID: 37308799 DOI: 10.1007/s43032-023-01282-0

Endometrial injury is one of the leading causes of female infertility and is caused by intrauterine surgery, endometrial infection, repeated abortion, or genital tuberculosis. Currently, there is little effective treatment to restore the fertility of patients with severe intrauterine adhesions and thin endometrium. Recent studies have confirmed the promising therapeutic effects of mesenchymal stem cell transplantation on various diseases with definite tissue injury. The aim of this study is to investigate the improvements of menstrual blood-derived endometrial stem cells (MenSCs) transplantation on functional restoration in the endometrium of mouse model. Therefore, ethanol-induced endometrial injury mouse models were randomly divided into two groups: the PBS-treated group, and the MenSCs-treated group. As expected, the endometrial thickness and gland number in the endometrium of MenSCs-treated mice were significantly improved compared to those of PBS-treated mice (P

Fulltext Anxiety and its risk factors among non-Japanese residents living in Japan undergoing COVID-19 situation: A cross-sectional survey

Luu MN, Imoto A, Matsuo Y, Huy NT, Qarawi A, Alhady STM, et al.

PLoS One, 2024;19(3):e0280144.

PMID: 38489310 DOI: 10.1371/journal.pone.0280144

INTRODUCTION: In the context of collective efforts taken in Japan to control the spread of COVID-19, the state of emergency and social distancing have caused a negative impact on the mental health of all residents, including foreign communities in Japan. This study aimed to evaluate the level of anxiety and its associated factors among non-Japanese residents residing in Japan during the COVID-19 pandemic.

METHODS: A web-based survey in 13 languages was conducted among non-Japanese residents living in Japan during the COVID-19 situation. The State-Trait Anxiety Inventory assessed the level of anxiety-State (STAI-S) scores prorated from its six-item version. The multivariable logistic regression using the Akaike Information Criterion (AIC) method was performed to identify the associated factors of anxiety among participants.

RESULTS: From January to March 2021, we collected 392 responses. A total of 357 valid responses were analyzed. 54.6% of participants suffered from clinically significant anxiety (CSA). In multivariable logistic model analysis, the CSA status or the high level of anxiety was associated with three factors, including having troubles/difficulties in learning or working, decreased sleep duration, and decreased overall physical health (p<0.05).

CONCLUSION: Our study suggests several possible risk factors of anxiety among non-Japanese residents living in Japan undergoing the COVID-19 pandemic, including the troubles or difficulties in learning or working, the decrease in sleep duration, and the decrease in overall physical health.

Search for displaced supersymmetry in events with an electron and a muon with large impact parameters

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.

Phys Rev Lett, 2015 Feb 13;114(6):061801.

PMID: 25723204

A search for new long-lived particles decaying to leptons is presented using proton-proton collisions produced by the LHC at √[s]=8 TeV. Data used for the analysis were collected by the CMS detector and correspond to an integrated luminosity of 19.7 fb(-1). Events are selected with an electron and muon with opposite charges that both have transverse impact parameter values between 0.02 and 2 cm. The search has been designed to be sensitive to a wide range of models with nonprompt e-μ final states. Limits are set on the "displaced supersymmetry" model, with pair production of top squarks decaying into an e-μ final state via R-parity-violating interactions. The results are the most restrictive to date on this model, with the most stringent limit being obtained for a top squark lifetime corresponding to cτ=2 cm, excluding masses below 790 GeV at 95% confidence level.

Study of vector boson scattering and search for new physics in events with two same-sign leptons and two jets

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.

Phys Rev Lett, 2015 Feb 6;114(5):051801.

PMID: 25699433

A study of vector boson scattering in pp collisions at a center-of-mass energy of 8 TeV is presented. The data sample corresponds to an integrated luminosity of 19.4 fb(-1) collected with the CMS detector. Candidate events are selected with exactly two leptons of the same charge, two jets with large rapidity separation and high dijet mass, and moderate missing transverse energy. The signal region is expected to be dominated by electroweak same-sign W-boson pair production. The observation agrees with the standard model prediction. The observed significance is 2.0 standard deviations, where a significance of 3.1 standard deviations is expected based on the standard model. Cross section measurements for W(±)W(±) and WZ processes in the fiducial region are reported. Bounds on the structure of quartic vector-boson interactions are given in the framework of dimension-eight effective field theory operators, as well as limits on the production of doubly charged Higgs bosons.

Search for top squark and Higgsino production using diphoton Higgs boson decays

Chatrchyan S, Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, et al.

Phys Rev Lett, 2014 Apr 25;112(16):161802.

PMID: 24815637

Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top quark (the top squark) and the Higgs boson (Higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7 fb-1 of proton-proton collision data at s=8 TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the top squark mass below 360 to 410 GeV, depending on the Higgsino mass.

Search for Narrow Resonances Decaying to Dijets in Proton-Proton Collisions at sqrt[s]=13 TeV

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Phys Rev Lett, 2016 Feb 19;116(7):071801.

PMID: 26943527 DOI: 10.1103/PhysRevLett.116.071801

A search for narrow resonances in proton-proton collisions at sqrt[s]=13 TeV is presented. The invariant mass distribution of the two leading jets is measured with the CMS detector using a data set corresponding to an integrated luminosity of 2.4 fb^{-1}. The highest observed dijet mass is 6.1 TeV. The distribution is smooth and no evidence for resonant particles is observed. Upper limits at 95% confidence level are set on the production cross section for narrow resonances with masses above 1.5 TeV. When interpreted in the context of specific models, the limits exclude string resonances with masses below 7.0 TeV, scalar diquarks below 6.0 TeV, axigluons and colorons below 5.1 TeV, excited quarks below 5.0 TeV, color-octet scalars below 3.1 TeV, and W^{'} bosons below 2.6 TeV. These results significantly extend previously published limits.

Study of B Meson Production in p+Pb Collisions at √[S(NN)]=5.02 TeV Using Exclusive Hadronic Decays

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Phys Rev Lett, 2016 Jan 22;116(3):032301.

PMID: 26849587 DOI: 10.1103/PhysRevLett.116.032301

The production cross sections of the B^{+}, B^{0}, and B_{s}^{0} mesons, and of their charge conjugates, are measured via exclusive hadronic decays in p+Pb collisions at the center-of-mass energy sqrt[s_{NN}]=5.02 TeV with the CMS detector at the CERN LHC. The data set used for this analysis corresponds to an integrated luminosity of 34.6 nb^{-1}. The production cross sections are measured in the transverse momentum range between 10 and 60 GeV/c. No significant modification is observed compared to proton-proton perturbative QCD calculations scaled by the number of incoherent nucleon-nucleon collisions. These results provide a baseline for the study of in-medium b quark energy loss in Pb+Pb collisions.

Search for monotop signatures in proton-proton collisions at √s=8 TeV

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.

Phys Rev Lett, 2015 Mar 13;114(10):101801.

PMID: 25815923

Results are presented from a search for new decaying massive particles whose presence is inferred from an imbalance in transverse momentum and which are produced in association with a single top quark that decays into a bottom quark and two light quarks. The measurement is performed using 19.7 fb^{-1} of data from proton-proton collisions at a center-of-mass energy of 8 TeV, collected with the CMS detector at the CERN LHC. No deviations from the standard model predictions are observed and lower limits are set on the masses of new invisible bosons. In particular, scalar and vector particles, with masses below 330 and 650 GeV, respectively, are excluded at 95% confidence level, thereby substantially extending a previous limit published by the CDF Collaboration.

Fulltext Relative Modification of Prompt ψ(2S) and J/ψ Yields from pp to PbPb Collisions at sqrt[s_{NN}]=5.02 TeV

Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.

Phys Rev Lett, 2017 Apr 21;118(16):162301.

PMID: 28474955 DOI: 10.1103/PhysRevLett.118.162301

The relative modification of the prompt ψ(2S) and J/ψ yields from pp to PbPb collisions, at the center-of-mass energy of 5.02 TeV per nucleon pair, is presented. The analysis is based on pp and PbPb data samples collected by the CMS experiment at the LHC in 2015, corresponding to integrated luminosities of 28.0 pb^{-1} and 464 μb^{-1}, respectively. The double ratio of measured yields of prompt charmonia reconstructed through their decays into muon pairs, (N_{ψ(2S)}/N_{J/ψ})_{PbPb}/(N_{ψ(2S)}/N_{J/ψ})_{pp}, is determined as a function of PbPb collision centrality and charmonium transverse momentum p_{T}, in two kinematic intervals: |y|<1.6 covering 6.5y|<2.4 covering 3

Fulltext Observation of Charge-Dependent Azimuthal Correlations in p-Pb Collisions and Its Implication for the Search for the Chiral Magnetic Effect

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Phys Rev Lett, 2017 Mar 24;118(12):122301.

PMID: 28388204 DOI: 10.1103/PhysRevLett.118.122301

Charge-dependent azimuthal particle correlations with respect to the second-order event plane in p-Pb and PbPb collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV have been studied with the CMS experiment at the LHC. The measurement is performed with a three-particle correlation technique, using two particles with the same or opposite charge within the pseudorapidity range |η|<2.4, and a third particle measured in the hadron forward calorimeters (4.4

Study of Jet Quenching with Z+jet Correlations in Pb-Pb and pp Collisions at sqrt[s]_{NN}=5.02 TeV

Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.

Phys Rev Lett, 2017 Aug 25;119(8):082301.

PMID: 28952777 DOI: 10.1103/PhysRevLett.119.082301

The production of jets in association with Z bosons, reconstructed via the μ^{+}μ^{-} and e^{+}e^{-} decay channels, is studied in pp and, for the first time, in Pb-Pb collisions. Both data samples were collected by the CMS experiment at the LHC, at a nucleon-nucleon center-of-mass energy of 5.02 TeV. The Pb-Pb collisions were analyzed in the 0%-30% centrality range. The back-to-back azimuthal alignment was studied in both pp and Pb-Pb collisions for Z bosons with transverse momentum p_{T}^{Z}>60 GeV/c and a recoiling jet with p_{T}^{jet}>30 GeV/c. The p_{T} imbalance x_{jZ}=p_{T}^{jet}/p_{T}^{Z}, as well as the average number of jet partners per Z, R_{jZ}, was studied in intervals of p_{T}^{Z}. The R_{jZ} is found to be smaller in Pb-Pb than in pp collisions, which suggests that in Pb-Pb collisions a larger fraction of partons associated with the Z bosons fall below the 30 GeV/c p_{T}^{jet} threshold because they lose energy.

Fulltext Search for Dark Matter and Supersymmetry with a Compressed Mass Spectrum in the Vector Boson Fusion Topology in Proton-Proton Collisions at sqrt[s]=8 TeV

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Phys Rev Lett, 2017 Jan 13;118(2):021802.

PMID: 28128610 DOI: 10.1103/PhysRevLett.118.021802

A first search for pair production of dark matter candidates through vector boson fusion in proton-proton collisions at sqrt[s]=8 TeV is performed with the CMS detector. The vector boson fusion topology enhances missing transverse momentum, providing a way to probe supersymmetry, even in the case of a compressed mass spectrum. The data sample corresponds to an integrated luminosity of 18.5 fb^{-1}, recorded by the CMS experiment. The observed dijet mass spectrum is consistent with the standard model expectation. In an effective field theory, dark matter masses are explored as a function of contact interaction strength. The most stringent limit on bottom squark production with mass below 315 GeV is also reported, assuming a 5 GeV mass difference with respect to the lightest neutralino.

Fulltext Search for Resonant Production of High-Mass Photon Pairs in Proton-Proton Collisions at sqrt[s]=8 and 13 TeV

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Phys Rev Lett, 2016 Jul 29;117(5):051802.

PMID: 27517765 DOI: 10.1103/PhysRevLett.117.051802

A search for the resonant production of high-mass photon pairs is presented. The analysis is based on samples of proton-proton collision data collected by the CMS experiment at center-of-mass energies of 8 and 13 TeV, corresponding to integrated luminosities of 19.7 and 3.3 fb^{-1}, respectively. The interpretation of the search results focuses on spin-0 and spin-2 resonances with masses between 0.5 and 4 TeV and with widths, relative to the mass, between 1.4×10^{-4} and 5.6×10^{-2}. Limits are set on scalar resonances produced through gluon-gluon fusion, and on Randall-Sundrum gravitons. A modest excess of events compatible with a narrow resonance with a mass of about 750 GeV is observed. The local significance of the excess is approximately 3.4 standard deviations. The significance is reduced to 1.6 standard deviations once the effect of searching under multiple signal hypotheses is considered. More data are required to determine the origin of this excess.

Fulltext Measurement of Long-Range Near-Side Two-Particle Angular Correlations in pp Collisions at sqrt[s]=13 TeV

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Phys Rev Lett, 2016 Apr 29;116(17):172302.

PMID: 27176516 DOI: 10.1103/PhysRevLett.116.172302

Results on two-particle angular correlations for charged particles produced in pp collisions at a center-of-mass energy of 13 TeV are presented. The data were taken with the CMS detector at the LHC and correspond to an integrated luminosity of about 270 nb^{-1}. The correlations are studied over a broad range of pseudorapidity (|η|<2.4) and over the full azimuth (ϕ) as a function of charged particle multiplicity and transverse momentum (p_{T}). In high-multiplicity events, a long-range (|Δη|>2.0), near-side (Δϕ≈0) structure emerges in the two-particle Δη-Δϕ correlation functions. The magnitude of the correlation exhibits a pronounced maximum in the range 1.0

Fulltext Search for Narrow Resonances in Dijet Final States at sqrt[s]=8 TeV with the Novel CMS Technique of Data Scouting

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Phys Rev Lett, 2016 Jul 15;117(3):031802.

PMID: 27472109 DOI: 10.1103/PhysRevLett.117.031802

A search for narrow resonances decaying into dijet final states is performed on data from proton-proton collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 18.8 fb^{-1}. The data were collected with the CMS detector using a novel technique called data scouting, in which the information associated with these selected events is much reduced, permitting collection of larger data samples. This technique enables CMS to record events containing jets at a rate of 1 kHz, by collecting the data from the high-level-trigger system. In this way, the sensitivity to low-mass resonances is increased significantly, allowing previously inaccessible couplings of new resonances to quarks and gluons to be probed. The resulting dijet mass distribution yields no evidence of narrow resonances. Upper limits are presented on the resonance cross sections as a function of mass, and compared with a variety of models predicting narrow resonances. The limits are translated into upper limits on the coupling of a leptophobic resonance Z_{B}^{'} to quarks, improving on the results obtained by previous experiments for the mass range from 500 to 800 GeV.

Evidence for the Higgs Boson Decay to a Z Boson and a Photon at the LHC

Aad G, Abbott B, Abeling K, Abicht NJ, Abidi SH, Aboulhorma A, et al.

Phys Rev Lett, 2024 Jan 12;132(2):021803.

PMID: 38277607 DOI: 10.1103/PhysRevLett.132.021803

The first evidence for the Higgs boson decay to a Z boson and a photon is presented, with a statistical significance of 3.4 standard deviations. The result is derived from a combined analysis of the searches performed by the ATLAS and CMS Collaborations with proton-proton collision datasets collected at the CERN Large Hadron Collider (LHC) from 2015 to 2018. These correspond to integrated luminosities of around 140 fb^{-1} for each experiment, at a center-of-mass energy of 13 TeV. The measured signal yield is 2.2±0.7 times the standard model prediction, and agrees with the theoretical expectation within 1.9 standard deviations.

Fulltext Parental vaccine hesitancy and acceptance of a COVID-19 vaccine: An internet-based survey in the US and five Asian countries

Joachim G, Shih SF, Singh A, Rajamoorthy Y, Harapan H, Chang HY, et al.

PLOS Glob Public Health, 2024;4(2):e0002961.

PMID: 38416781 DOI: 10.1371/journal.pgph.0002961

COVID-19 vaccination rates for children globally are relatively low. This study aimed to investigate parental vaccine hesitancy and parents' acceptance of a COVID-19 for their children for their children in the United States, China, Taiwan, India, Indonesia, and Malaysia.We analyzed data from an opt-in, internet-based cross-sectional study (n = 23,940). Parents were asked about their acceptance of a COVID-19 vaccine for their children, and if they would accept the vaccine with different risk and effectiveness profiles for themselves. Poisson regression was used to generate prevalence ratios (PR) of the relationship between vaccine acceptance for a child and vaccine profile, by country and waves and overall. Between August 2020 and June 2021, COVID-19 vaccine acceptance for children decreased in the United States (89% to 72%) and Taiwan (79% to 71%), increased in India (91% to 96%) and Malaysia (81% to 91%), and was stable in Indonesia (86%) and China (at 87%-90%). Vaccine risk and effectiveness profiles did not consistently affect parent's acceptance of a COVID-19 vaccine for their children. Instead, being not hesitant was a large driver of vaccine acceptance (PR: 1.24, 95% CI: 1.14, 1.36). Adolescent COVID-19 vaccination have already been established in many high and middle-income countries, but our study suggests that there is a movement of vaccine hesitancy which could impede the success of future pediatric and adolescent COVID-19 vaccination programs.

Fulltext A study of COVID-19 vaccination in the US and Asia: The role of media, personal experiences, and risk perceptions

Akel KB, Noppert GA, Rajamoorthy Y, Lu Y, Singh A, Harapan H, et al.

PLOS Glob Public Health, 2022;2(7):e0000734.

PMID: 36962371 DOI: 10.1371/journal.pgph.0000734

The COVID-19 pandemic presents an opportunity to assess the relationship between personal experiences and vaccine decision-making. The aim of this study was to examine the associations between experiences with COVID-19 and COVID-19 vaccination status. We administered 28 repeated cross-sectional, online surveys between June 2020 and June 2021 in the US and Asia. The main exposure was media showing COVID-19 cases, and we distinguished those with no such experience, those seeing a not severe case of disease, and those seeing a severe case of disease. Logistic regression models estimated the association between experience and acceptance of a hypothetical COVID-19 vaccine (pre-rollout) or actual vaccination (post-rollout). We explored perceived susceptibility as a potential mediator. Intent to vaccinate was lowest in the US and Taiwan, and highest in India, Indonesia, and China. Across all countries, seeing a severe case of COVID-19 in the media was associated with 1.72 times higher odds of vaccination intent in 2020 (95% CI: 1.46, 2.02) and 2.13 times higher odds of vaccination in 2021 (95% CI: 1.70, 2.67), compared to those not seeing a case or a less severe case. Perceived susceptibility was estimated to mediate 25% of the relationship with hypothetical vaccination (95% CI: 18%, 31%, P<0.0001), and 16% of the relationship with actual vaccination 16% (95% CI: 12%, 19%, P<0.0001). Seriousness of experiences could relate to intention to vaccinate against COVID-19. Media exposures are a modifiable experience, and this study highlights how this experience can relate to risk perceptions and eventual vaccination, across a variety of countries where the course of the pandemic differed.

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