The clinical outcomes and effectiveness of antiviral agents among underweight patients with COVID-19

OBJECTIVES

This study investigated the outcomes of underweight patients with COVID-19 and the effectiveness of antiviral agents in this population.

METHODS

A retrospective cohort study using theTriNetX research network was conducted. Propensity score matching (PSM) was employed to balance the first cohort involving COVID-19 patients with underweight and normal-weight. In the second cohort, underweight patients receiving antiviral agents and untreated individuals were matched using PSM. The primary outcome was a composite of all-cause hospitalization and death during the 7-30-day follow-up period.

RESULTS

After PSM, the first cohort including each group of 13,502 patients with balanced baseline characteristics were identified for comparing the outcome of patients with underweight and normal weight. The underweight group had a higher risk of the composite primary outcome than those with normal weight (hazard ratio [HR], 1.251; 95% confidence interval [CI], 1.132-1.382). The second cohort included each 884 underweight patients with and without receiving antivirals.Compared with untreated patients, those receiving antiviral treatment had a lower risk of composite primary outcomes (HR, 0.426; 95% CI, 0.278-0.653).

CONCLUSION

Underweight status may be associated with a higher risk of all-cause hospitalization and death in patients with COVID-19.Among underweight patients, antiviral agents demonstrated clinically beneficial effects.

Modulation of the microRNA-6089/E2F transcription factor2 axis by querceting: implications for osteoblast viability, proliferation, migration, and osteogenic differentiation in fracture healing

Quercetin is widely distributed in plants as a flavonol compound with multiple biological activities. It has been found that quercetin can regulate bone homeostasis through multiple pathways and targets. This study investigated the role and specific molecular mechanisms of quercetin in regulating osteoblast viability, proliferation, migration and osteogenic differentiation. A mouse model of traumatic fracture was established and then 100 mg/kg quercetin corn oil suspension was gavaged at the same time every day for 28 days. miR-6089 and E2F transcription factor 2 (E2F2) expression levels in mice were measured. Fracture healing in mice was observed. MC3T3-E1 cells were transfected with plasmids targeting miR-6089 and E2F2, and cell viability, proliferation, migration, apoptosis, and osteogenic differentiation were determined. The targeting relationship between miR-6089 and E2F2 was verified. In vivo experiments showed that quercetin significantly increased osteocalcin (OCN) expression (P<0.05) and promoted fracture healing in traumatic fracture (TF) mice. miR-6089 expression was down-regulated (P<0.05) and E2F2 expression was up-regulated (P<0.05) in TF mice. Quercetin promoted miR-6089 expression and inhibited E2F2 expression (both P<0.05). In vitro results showed that quercetin promoted miR-6089 expression and inhibited E2F2 expression in a dose-dependent manner (both P<0.05). Quercetin dose-dependently promoted MC3T3-E1 cell viability, proliferation, migration, and osteogenic differentiation, and inhibited MC3T3-E1 cell apoptosis (all P<0.05). Up-regulating miR-6089 further promoted MC3T3-E1 cell viability, proliferation, migration and osteogenic differentiation, and inhibited MC3T3-E1 cell apoptosis (all P<0.05). miR-6089 targeted and regulated E2F2 expression. Up-regulating E2F2 attenuated the promoting effect of up-regulated miR-6089 on MC3T3-E1 cell viability, proliferation, migration, osteogenic differentiation, and inhibition of apoptosis (all P<0.05). We conclude that quercetin enhances osteoblast viability, proliferation, migration, and osteogenic differentiation by modulating the miR-6089/E2F2 axis, thereby promoting fracture healing.

Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A

We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15  PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.

Study of High-Transverse-Momentum Higgs Boson Production in Association with a Vector Boson in the qqbb Final State with the ATLAS Detector

This Letter presents the first study of Higgs boson production in association with a vector boson (V=W or Z) in the fully hadronic qqbb final state using data recorded by the ATLAS detector at the LHC in proton-proton collisions at sqrt[s]=13  TeV and corresponding to an integrated luminosity of 137  fb^{-1}. The vector bosons and Higgs bosons are each reconstructed as large-radius jets and tagged using jet substructure techniques. Dedicated tagging algorithms exploiting b-tagging properties are used to identify jets consistent with Higgs bosons decaying into bb[over ¯]. Dominant backgrounds from multijet production are determined directly from the data, and a likelihood fit to the jet mass distribution of Higgs boson candidates is used to extract the number of signal events. The VH production cross section is measured inclusively and differentially in several ranges of Higgs boson transverse momentum: 250-450, 450-650, and greater than 650 GeV. The inclusive signal yield relative to the standard model expectation is observed to be μ=1.4_{-0.9}^{+1.0} and the corresponding cross section is 3.1±1.3(stat)_{-1.4}^{+1.8}(syst)  pb.

Clinical effectiveness of oral antiviral agents for treating non-hospitalized COVID-19 patients with chronic kidney disease

OBJECTIVES

This study examined the effectiveness of nirmatrelvir plus ritonavir (NMV-r) and molnupiravir (MOV) in treating COVID-19 among chronic kidney disease (CKD) patients.

METHODS

This retrospective cohort study, using the TriNetX research network, identified stage 3-5 CKD and end-stage kidney disease (ESKD) patients with non-hospitalized COVID-19 between 1 January 2022, and 31 May 2023. Propensity score matching (PSM) was used to compare patients on NMV-r or MOV (antiviral group) against those not receiving these treatments (control group). The primary composite outcome was the cumulative hazard ratio (HR) for all-cause hospitalization or death within the 30-day follow-up.

RESULTS

After PSM, two balanced cohorts of 6,275 patients each were established. The antiviral group exhibited a lower incidence of all-cause hospitalization or mortality (5.93% vs. 9.53%; HR: 0.626; 95% CI: 0.550-0.713) than controls. Additionally, antiviral recipients were associated with a lower risk of all-cause hospitalization (HR: 0.679; 95% CI: 0.594-0.777) and mortality (HR: 0.338; 95% CI: 0.227-0.504). The beneficial effects of antiviral agents were consistent across sex, age, vaccination status, antiviral type, and CKD stage.

CONCLUSION

Oral antiviral agents could be associated with lower rates of all-cause hospitalization or death among non-hospitalized COVID-19 patients with CKD.

Measurement of the Centrality Dependence of the Dijet Yield in p+Pb Collisions at sqrt[s_{NN}]=8.16 TeV with the ATLAS Detector

ATLAS measured the centrality dependence of the dijet yield using 165  nb^{-1} of p+Pb data collected at sqrt[s_{NN}]=8.16  TeV in 2016. The event centrality, which reflects the p+Pb impact parameter, is characterized by the total transverse energy registered in the Pb-going side of the forward calorimeter. The central-to-peripheral ratio of the scaled dijet yields, R_{CP}, is evaluated, and the results are presented as a function of variables that reflect the kinematics of the initial hard parton scattering process. The R_{CP} shows a scaling with the Bjorken x of the parton originating from the proton, x_{p}, while no such trend is observed as a function of x_{Pb}. This analysis provides unique input to understanding the role of small proton spatial configurations in p+Pb collisions by covering parton momentum fractions from the valence region down to x_{p}∼10^{-3} and x_{Pb}∼4×10^{-4}.

Association between vitamin D deficiency and post-acute outcomes of SARS-CoV-2 infection

OBJECTIVES

This study aimed to investigate the association between vitamin D deficiency (VDD) and post-acute outcomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

METHODS

This retrospective study used the TriNetX research network to identify COVID-19 patients between January 1 and November 30, 2022. Patients were matched using propensity score matching (PSM) and divided into VDD (< 20 ng/mL) and control (≥ 20 ng/mL) groups. The primary outcome was a composite of post-COVID-19 condition (identified by ICD-10 code), all-cause emergency department (ED) visits, hospitalization, and death during the follow-up period (90-180 days) after the diagnosis of COVID-19.

RESULTS

From an initial recruitment of 42,674 non-hospitalized patients with COVID-19 and known 25(OH)D status, a VDD group of 8300 was identified and propensity matched with 8300 controls. During the follow-up period, the VDD group had a higher risk of the primary outcome than did the control group [hazard ratio (HR) = 1.122; 95% confidence interval (CI) = 1.041-1.210]. The VDD group also had a higher risk of all-cause ED visits (HR = 1.114; 95% CI = 1.012-1.226), all-cause hospitalization (HR = 1.230; 95% CI = 1.105-1.369), and all-cause death (HR = 1.748; 95% CI = 1.047-2.290) but not post-COVID-19 condition (HR = 0.980; 95% CI = 0.630-1.523), individually.

CONCLUSION

Among the COVID-19 patients, VDD might be associated with a higher risk of all-cause ED visits, hospitalization, and death during the post-acute phase.

Search for New Phenomena in Two-Body Invariant Mass Distributions Using Unsupervised Machine Learning for Anomaly Detection at sqrt[s]=13 TeV with the ATLAS Detector

Searches for new resonances are performed using an unsupervised anomaly-detection technique. Events with at least one electron or muon are selected from 140  fb^{-1} of pp collisions at sqrt[s]=13  TeV recorded by ATLAS at the Large Hadron Collider. The approach involves training an autoencoder on data, and subsequently defining anomalous regions based on the reconstruction loss of the decoder. Studies focus on nine invariant mass spectra that contain pairs of objects consisting of one light jet or b jet and either one lepton (e,μ), photon, or second light jet or b jet in the anomalous regions. No significant deviations from the background hypotheses are observed. Limits on contributions from generic Gaussian signals with various widths of the resonance mass are obtained for nine invariant masses in the anomalous regions.

[Research progress in clinical diagnosis and treatment of osteosarcoma of the jaw]

Osteosarcoma of the jaw (JOS), is a relatively rare type of osteosarcoma, with a unique pathogenesis and pathological manifestations. The clinical manifestation of JOS is not characteristic, and it often needs to be diagnosed by combining radiological and pathological examination. At present, the conventional treatment of JOS is a comprehensive treatment based on surgery and supplemented by radiotherapy and chemotherapy. Recently, the emergence of new therapies such as immunotherapy, gene therapy, phototherapy and traditional Chinese medicine has provided more choices for treatment and brought new hope to patients with JOS. Therefore, this article summarized the current understanding of diagnosis and the latest treatment development of JOS.

Observation of WZγ Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector

This Letter reports the observation of WZγ production and a measurement of its cross section using 140.1±1.2  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. The WZγ production cross section, with both the W and Z bosons decaying leptonically, pp→WZγ→ℓ^{'}^{±}νℓ^{+}ℓ^{-}γ (ℓ^{(^{'})}=e, μ), is measured in a fiducial phase-space region defined such that the leptons and the photon have high transverse momentum and the photon is isolated. The cross section is found to be 2.01±0.30(stat)±0.16(syst)  fb. The corresponding standard model predicted cross section calculated at next-to-leading order in perturbative quantum chromodynamics and at leading order in the electroweak coupling constant is 1.50±0.06  fb. The observed significance of the WZγ signal is 6.3σ, compared with an expected significance of 5.0σ.

Combined Measurement of the Higgs Boson Mass from the H→γγ and H→ZZ^{*}→4ℓ Decay Channels with the ATLAS Detector Using sqrt[s]=7, 8, and 13 TeV pp Collision Data

A measurement of the mass of the Higgs boson combining the H→ZZ^{*}→4ℓ and H→γγ decay channels is presented. The result is based on 140  fb^{-1} of proton-proton collision data collected by the ATLAS detector during LHC run 2 at a center-of-mass energy of 13 TeV combined with the run 1 ATLAS mass measurement, performed at center-of-mass energies of 7 and 8 TeV, yielding a Higgs boson mass of 125.11±0.09(stat)±0.06(syst)=125.11±0.11  GeV. This corresponds to a 0.09% precision achieved on this fundamental parameter of the Standard Model of particle physics.

Search for Dark Photons in Rare Z Boson Decays with the ATLAS Detector

A search for events with a dark photon produced in association with a dark Higgs boson via rare decays of the standard model Z boson is presented, using 139  fb^{-1} of sqrt[s]=13  TeV proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider. The dark boson decays into a pair of dark photons, and at least two of the three dark photons must each decay into a pair of electrons or muons, resulting in at least two same-flavor opposite-charge lepton pairs in the final state. The data are found to be consistent with the background prediction, and upper limits are set on the dark photon's coupling to the dark Higgs boson times the kinetic mixing between the standard model photon and the dark photon, α_{D}ϵ^{2}, in the dark photon mass range of [5, 40] GeV except for the ϒ mass window [8.8, 11.1] GeV. This search explores new parameter space not previously excluded by other experiments.

Association between nirmatrelvir plus ritonavir and the outcomes of non-hospitalized obese patients with COVID-19

OBJECTIVE

To investigate the association between nirmatrelvir plus ritonavir (NMV-r) and the outcomes of non-hospitalized obese patients with coronavirus disease 2019 (COVID-19).

METHODS

This retrospective cohort study used the TriNetX research network to identify non-hospitalized obese adult patients with COVID-19 between 1 January 2022 and 30 June 2023. Propensity score matching was used to match patients receiving NMV-r (NMV-r group) with those not receiving NMV-r (control group). The primary outcome was the compositive outcome of all-cause emergency department (ED) visits, hospitalization or death during the 30-day follow-up period.

RESULTS

Using propensity score matching methods, two cohorts of 30,969 patients each with balanced baseline characteristics were identified. During the follow-up period, the NMV-r group had a lower risk of all-cause ED visits, hospitalization or death [4.80% (n=1489) vs 5.50% (n=1705); hazard ratio (HR) 0.900, 95% confidence interval (CI) 0.839-0.965]. Compared with the control group, the NMV-r group had a lower risk of all-cause ED visits (HR 0.812, 95% CI 0.740-0.891) and all-cause mortality (HR 0.089, 95% CI 0.027-0.288). The lower risk in the NMV-r group compared with the control group was observed consistently in most subgroup analyses according to body mass index (30.0-34.9 kg/m2: HR 0.68, 95% CI 0.55-0.82; 35.0-39.9 kg/m2: HR 0.67, 95% CI 0.52-0.87), age (4-64 years: HR 0.83, 95% CI 0.75-0.92; ≥65 years: HR 0.88, 95% CI 0.79-0.98), sex (men: HR 0.69, 95% CI 0.60-0.79; women: HR 0.69, 95% CI 0.63-0.76) and vaccination status (unvaccinated: HR 0.75, 95% CI 0.70-0.81).

CONCLUSION

NMV-r is associated with reduced risk of all-cause ED visits, hospitalization and death for non-hospitalized obese patients with COVID-19. Accordingly, these findings support the use of NMV-r in obese patients.

Observation of Single-Top-Quark Production in Association with a Photon Using the ATLAS Detector

This Letter reports the observation of single top quarks produced together with a photon, which directly probes the electroweak coupling of the top quark. The analysis uses 139  fb^{-1} of 13 TeV proton-proton collision data collected with the ATLAS detector at the Large Hadron Collider. Requiring a photon with transverse momentum larger than 20 GeV and within the detector acceptance, the fiducial cross section is measured to be 688±23(stat) _{-71}^{+75}(syst)  fb, to be compared with the standard model prediction of 515_{-42}^{+36}  fb at next-to-leading order in QCD.

Nutritional deficiency anemia and post-acute sequelae in patients with severe acute respiratory syndrome coronavirus 2 infection: A six-month retrospective cohort analysis of 30 892 patients

The effect of anemia on the post-acute outcome of patients with severe acute respiratory syndrome coronavirus 2 infection was unclear. This study aimed to investigate the potential association between nutritional deficiency anemia (NDA) status and post-acute sequelae of patients with SARS-CoV-2 infection. This retrospective cohort study included patients with coronavirus disease (COVID-19) from January 1, 2022 to November 30, 2022 using the TriNetX research network. The patients were grouped into the NDA group comprising patients diagnosed with NDA and the control group comprising patients without NDA, and propensity score matching (PSM) was performed to balance the two groups. The primary outcome was a composite of post-COVID-19 condition, all-cause hospitalization, and all-cause death. The secondary outcomes were any individual outcomes of the primary composite. The follow-up period was set at 90-180 days after COVID-19 diagnosis. Two cohorts comprising 15 446 nonhospitalized patients with COVID-19 in each group with balanced baseline characteristics were created using PSM. During the follow-up period, the NDA group demonstrated a higher risk of the composite primary outcome, including post-COVID-19 condition, all-cause hospitalization, or all-cause death (hazard ratio [HR], 1.896; 95% confidence interval [CI] =  1.757-2.045). Regarding secondary outcomes, the NDA group was associated with worse outcomes, including post-COVID-19 condition (HR, 1.992; 95% CI = 1.403-2.828), all-cause hospitalization (HR, 1.856; 95% CI = 1.714-2.009), and all-cause death (HR, 3.922; 95% CI = 2.910-5.285) compared to the control group. Among nonhospitalized patients with COVID-19, NDA was associated with a higher risk of post-COVID-19 condition, all-cause hospitalization, and all-cause death during the 90-180-day follow-up period.

Clinical efficacy of enteral nutrition feeding modalities in critically ill patients: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

In intensive care units (ICUs), both continuous and intermittent feeding are commonly used for early enteral nutrition (EN). However, whether continuous feeding is a preferable feeding modality compared to intermittent feeding remains unclear. Therefore, this meta-analysis assessed the clinical efficacy of both EN feeding modalities in critically ill patients.

METHODS

The PubMed, Embase, and Cochrane Library databases were searched from their inception dates to December 29, 2022. The search did not involve language restrictions (PROSPERO CRD42022371756). Randomized controlled trials (RCTs) comparing the clinical efficacy and safety of continuous feeding and intermittent feeding in critically ill patients in ICUs were included.

RESULTS

We included 13 RCTs involving 785 patients. Compared with intermittent feeding, continuous feeding was associated with a lower mortality rate (relative risk [RR], 0.68; 95% confidence interval [CI], 0.47, 0.98; p = 0.04) but a higher risk of constipation (RR, 1.57; 95% CI, 1.02, 2.43; p = 0.04). Trial sequential analysis (TSA) for mortality rate presented a cumulative Z-curve crossing the traditional boundary, but the curve did not cross the TSA boundary for benefit. No significant differences were found in the aspiration/pneumonia rate (RR, 1.19; 95% CI, 0.51, 2.75; p = 0.69), diarrhea rate (RR, 0.82; 95% CI, 0.58, 1.16; p = 0.26), or increased gastric residual volumes (RR, 1.05; 95% CI, 0.58, 1.90; p = 0.86) between the groups.

CONCLUSION

Despite the low certainty of evidence, compared with intermittent feeding, continuous feeding may reduce the mortality rate in critically ill patients in ICU. Additional studies are needed to provide more evidence and validate the findings.

[Clinical analysis of adult oculomoclonus-myoclonus syndrome with vertigo]

The clinical manifestation, physical and laboratory examination, electrophysiological, and imaging data of 2 female adult OMS patients with vertigo were analyzed at the Department of Neurology of the First Medical Center of Chinese PLA General Hospital from February 2021 to March 2022. The treatment strategy and clinical outcome were followed up. The two female patients were aged 42 and 66 years. Anti-NMDA receptor antibody and anti-GABAB receptor antibody were detected in serological screening, respectively. The two patients met the diagnostic criteria for OMS, and one was screened for breast tumor. The clinical symptoms of the two patients were relieved after immunomodulation therapy. OMS is a group of rare clinical syndromes; its clinical evaluation process should be standardized and the etiology should be actively searched for.

Measurement of Suppression of Large-Radius Jets and Its Dependence on Substructure in Pb+Pb Collisions at sqrt[s_{NN}]=5.02 TeV with the ATLAS Detector

This letter presents a measurement of the nuclear modification factor of large-radius jets in sqrt[s_{NN}]=5.02  TeV Pb+Pb collisions by the ATLAS experiment. The measurement is performed using 1.72  nb^{-1} and 257  pb^{-1} of Pb+Pb and pp data, respectively. The large-radius jets are reconstructed with the anti-k_{t} algorithm using a radius parameter of R=1.0, by reclustering anti-k_{t} R=0.2 jets, and are measured over the transverse momentum (p_{T}) kinematic range of 158 Collapse

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Measurement of the Sensitivity of Two-Particle Correlations in pp Collisions to the Presence of Hard Scatterings

A key open question in the study of multiparticle production in high-energy pp collisions is the relationship between the "ridge"-i.e., the observed azimuthal correlations between particles in the underlying event that extend over all rapidities-and hard or semihard scattering processes. In particular, it is not known whether jets or their soft fragments are correlated with particles in the underlying event. To address this question, two-particle correlations are measured in pp collisions at sqrt[s]=13  TeV using data collected by the ATLAS experiment at the LHC, with an integrated luminosity of 15.8  pb^{-1}, in two different configurations. In the first case, charged particles associated with jets are excluded from the correlation analysis, while in the second case, correlations are measured between particles within jets and charged particles from the underlying event. Second-order flow coefficients, v_{2}, are presented as a function of event multiplicity and transverse momentum. These measurements show that excluding particles associated with jets does not affect the measured correlations. Moreover, particles associated with jets do not exhibit any significant azimuthal correlations with the underlying event, ruling out hard processes contributing to the ridge.

Observation of an Excess of Dicharmonium Events in the Four-Muon Final State with the ATLAS Detector

A search is made for potential ccc[over ¯]c[over ¯] tetraquarks decaying into a pair of charmonium states in the four muon final state using proton-proton collision data at sqrt[s]=13  TeV, corresponding to an integrated luminosity of 140  fb^{-1} recorded by the ATLAS experiment at LHC. Two decay channels, J/ψ+J/ψ→4μ and J/ψ+ψ(2S)→4μ, are studied. Backgrounds are estimated based on a hybrid approach involving Monte Carlo simulations and data-driven methods. Statistically significant excesses with respect to backgrounds dominated by the single parton scattering are seen in the di-J/ψ channel consistent with a narrow resonance at 6.9 GeV and a broader structure at lower mass. A statistically significant excess is also seen in the J/ψ+ψ(2S) channel. The fitted masses and decay widths of the structures are reported.

Observation of the γγ→ττ Process in Pb+Pb Collisions and Constraints on the τ-Lepton Anomalous Magnetic Moment with the ATLAS Detector

This Letter reports the observation of τ-lepton-pair production in ultraperipheral lead-lead collisions Pb+Pb→Pb(γγ→ττ)Pb and constraints on the τ-lepton anomalous magnetic moment a_{τ}. The dataset corresponds to an integrated luminosity of 1.44  nb^{-1} of LHC Pb+Pb collisions at sqrt[s_{NN}]=5.02  TeV recorded by the ATLAS experiment in 2018. Selected events contain one muon from a τ-lepton decay, an electron or charged-particle track(s) from the other τ-lepton decay, little additional central-detector activity, and no forward neutrons. The γγ→ττ process is observed in Pb+Pb collisions with a significance exceeding 5 standard deviations and a signal strength of μ_{ττ}=1.03_{-0.05}^{+0.06} assuming the standard model value for a_{τ}. To measure a_{τ}, a template fit to the muon transverse-momentum distribution from τ-lepton candidates is performed, using a dimuon (γγ→μμ) control sample to constrain systematic uncertainties. The observed 95% confidence-level interval for a_{τ} is -0.057 Collapse

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Measurement of Ultra-High-Energy Diffuse Gamma-Ray Emission of the Galactic Plane from 10 TeV to 1 PeV with LHAASO-KM2A

The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°10  TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60  TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.

Implementing a Novel Machine Learning System for Nutrition Education in Diabetes Mellitus Nutritional Clinic: Predicting 1-Year Blood Glucose Control

(1) Background: Persistent hyperglycemia in diabetes mellitus (DM) increases the risk of death and causes cardiovascular disease (CVD), resulting in significant social and economic costs. This study used a machine learning (ML) technique to build prediction models with the factors of lifestyle, medication compliance, and self-control in eating habits and then implemented a predictive system based on the best model to forecast whether blood glucose can be well-controlled within 1 year in diabetic patients attending a DM nutritional clinic. (2) Methods: Data were collected from outpatients aged 20 years or older with type 2 DM who received nutrition education in Chi Mei Medical Center. Multiple ML algorithms were used to build the predictive models. (3) Results: The predictive models achieved accuracies ranging from 0.611 to 0.690. The XGBoost model with the highest area under the curve (AUC) of 0.738 was regarded as the best and used for the predictive system implementation. SHAP analysis was performed to interpret the feature importance in the best model. The predictive system, evaluated by dietitians, received positive feedback as a beneficial tool for diabetes nutrition consultations. (4) Conclusions: The ML prediction model provides a promising approach for diabetes nutrition consultations to maintain good long-term blood glucose control, reduce diabetes-related complications, and enhance the quality of medical care.

Strong Constraints on Jet Quenching in Centrality-Dependent p+Pb Collisions at 5.02 TeV from ATLAS

Jet quenching is the process of color-charged partons losing energy via interactions with quark-gluon plasma droplets created in heavy-ion collisions. The collective expansion of such droplets is well described by viscous hydrodynamics. Similar evidence of collectivity is consistently observed in smaller collision systems, including pp and p+Pb collisions. In contrast, while jet quenching is observed in Pb+Pb collisions, no evidence has been found in these small systems to date, raising fundamental questions about the nature of the system created in these collisions. The ATLAS experiment at the Large Hadron Collider has measured the yield of charged hadrons correlated with reconstructed jets in 0.36  nb^{-1} of p+Pb and 3.6  pb^{-1} of pp collisions at 5.02 TeV. The yields of charged hadrons with p_{T}^{ch}>0.5  GeV near and opposite in azimuth to jets with p_{T}^{jet}>30 or 60 GeV, and the ratios of these yields between p+Pb and pp collisions, I_{pPb}, are reported. The collision centrality of p+Pb events is categorized by the energy deposited by forward neutrons from the struck nucleus. The I_{pPb} values are consistent with unity within a few percent for hadrons with p_{T}^{ch}>4  GeV at all centralities. These data provide new, strong constraints that preclude almost any parton energy loss in central p+Pb collisions.

Search for Heavy Neutral Leptons in Decays of W Bosons Using a Dilepton Displaced Vertex in sqrt[s]=13 TeV pp Collisions with the ATLAS Detector

A search for a long-lived, heavy neutral lepton (N) in 139  fb^{-1} of sqrt[s]=13  TeV pp collision data collected by the ATLAS detector at the Large Hadron Collider is reported. The N is produced via W→Nμ or W→Ne and decays into two charged leptons and a neutrino, forming a displaced vertex. The N mass is used to discriminate between signal and background. No signal is observed, and limits are set on the squared mixing parameters of the N with the left-handed neutrino states for the N mass range 3  GeV Collapse

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Test of CP Invariance in Higgs Boson Vector-Boson-Fusion Production Using the H→γγ Channel with the ATLAS Detector

A test of CP invariance in Higgs boson production via vector-boson fusion has been performed in the H→γγ channel using 139  fb^{-1} of proton-proton collision data at sqrt[s]=13  TeV collected by the ATLAS detector at the LHC. The optimal observable method is used to probe the CP structure of interactions between the Higgs boson and electroweak gauge bosons, as described by an effective field theory. No sign of CP violation is observed in the data. Constraints are set on the parameters describing the strength of the CP-odd component in the coupling between the Higgs boson and the electroweak gauge bosons in two effective field theory bases: d[over ˜] in the HISZ basis and c_{HW[over ˜]} in the Warsaw basis. The results presented are the most stringent constraints on CP violation in the coupling between Higgs and weak bosons. The 95% C.L. constraint on d[over ˜] is derived for the first time and the 95% C.L. constraint on c_{HW[over ˜]} has been improved by a factor of 5 compared to the previous measurement.

Efficacy and safety of adjunctive corticosteroids in the treatment of severe community-acquired pneumonia: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

This systematic review and meta-analysis aimed to investigate the clinical efficacy and safety of systemic corticosteroids in the treatment of patients with severe community-acquired pneumonia (sCAP).

METHODS

A comprehensive search was conducted using the Medline, Embase, ClinicalTrials.gov, and Scopus databases for articles published until April 24, 2023. Only randomized controlled trials (RCTs) that assessed the clinical efficacy and safety of adjunctive corticosteroids for treating sCAP were included. The primary outcome was the 30-day all-cause mortality.

RESULTS

A total of severe RCTs involving 1689 patients were included in this study. Overall, the study group had a lower mortality rate at day 30 than the control group (risk ratio [RR], 0.61; 95% CI 0.44 to 0.85; p < 0.01) with low heterogeneity (I2 = 0%, p = 0.42). Compared to the control group, the study group had a lower risk of the requirement of mechanical ventilation (RR 0.57; 95% CI 0.45 to 0.73; p < 0.001), shorter length of intensive care unit (MD - 0.8; 95% CI - 1.4 to - 0.1; p = 0.02), and hospital stay (MD - 1.1; 95% CI - 2.0 to - 0.1; p = 0.04). Finally, no significant difference was observed between the study and the control groups in terms of gastrointestinal tract bleeding (RR 1.03; 95% CI 0.49 to 2.18; p = 0.93), healthcare-associated infection (RR 0.89; 95% CI 0.60 to 1.32; p = 0.56), and acute kidney injury (RR 0.68; 95% CI 0.21 to 2.26; p = 0.53).

CONCLUSIONS

In patients with sCAP, adjunctive corticosteroids can provide survival benefits and improve clinical outcomes without increasing adverse events. However, because the pooled evidence remains inconclusive, further studies are required.

[Analysis of the clinical characteristics of 25 cases with parenchymal neuro-Behcet's disease]

Objective: To retrospectively investigate the clinical data, radiological characteristics, treatment, and outcome of patients with parenchymal neuro-Behcet's disease (P-NBD) with particular emphasis on dizziness. Methods: This was a cross-sectional study of clinical data from 25 patients with a confirmed diagnosis of P-NBD who were admitted to the Department of Neurology of the First Medical Center of Chinese People's Liberation Army General Hospital between 2010 and 2022. The median age of the population was 37 years (range: 17-85 years). Clinical data were retrospectively analyzed, including gender, age of onset, disease duration, clinical manifestations, serum immune indicators, cerebrospinal fluid (CSF) routine biochemical and cytokine levels, cranial and spinal magnetic resonance imaging (MRI) findings, treatment, and outcome. Results: The majority of patients were male (16 cases; 64.0%), the mean age of onset was (28±14) (range: 4-58 years), and the disease course was acute or subacute. Fever was the most common clinical presentation, and the complaint of dizziness was not uncommon (8/25 patients). Analysis of serum immune indices, including complement (C3 and C4), erythrocyte sedimentation rate, interleukin-1 (IL-1), IL-6, IL-8 and tumor necrotic factor-alpha were abnormal in 80.0% of patients (20/25). Most of the 16/25 patients who underwent lumbar puncture tests had normal intracranial pressure and increased CSF white cell count and protein [median values were 44 (15-380) ×10⁶/L and 0.73 (0.49-2.81) g/L, respectively]. Of the five patients who underwent CSF cytokine tests, four patients had abnormal results; of these, an elevated level of IL-6 was most common, followed by IL-1 and IL-8. The most common site of involvement in cranial MRI was the brainstem and basal ganglia (60.0% respectively), followed by white matter (48.0%) and the cortex (44.0%). Nine cases (36.0%) showed lesions with enhancement and six cases (24.0%) showed mass-like lesions. Three patients (12.0%) patients had lesions in the spinal cord, most frequently in the thoracic cord. All patients received immunological intervention therapy; during follow up, the majority had a favorable outcome. Conclusions: P-NBD is an autoimmune disease with multiple system involvement and diverse clinical manifestations. The symptom of dizziness is not uncommon and can be easily ignored. Early treatment with immunotherapy is important and can improve the outcome of these patients.

A tera-electron volt afterglow from a narrow jet in an extremely bright gamma-ray burst

Some gamma-ray bursts (GRBs) have a tera-electron volt (TeV) afterglow, but the early onset of this has not been observed. We report observations with the Large High Altitude Air Shower Observatory of the bright GRB 221009A, which serendipitously occurred within the instrument field of view. More than 64,000 photons >0.2 TeV were detected within the first 3000 seconds. The TeV flux began several minutes after the GRB trigger, then rose to a peak about 10 seconds later. This was followed by a decay phase, which became more rapid ~650 seconds after the peak. We interpret the emission using a model of a relativistic jet with half-opening angle ~0.8°. This is consistent with the core of a structured jet and could explain the high isotropic energy of this GRB.

Clinical efficacy of nirmatrelvir and ritonavir combination for treating diabetic patients with COVID-19

The aim of this study was to investigate the clinical efficacy of a combination of nirmatrelvir and ritonavir (NMV-r) for treating COVID-19 in patients with diabetes mellitus (DM). This retrospective cohort study used the TriNetX research network to identify adult diabetic patients with COVID-19 between January 1, 2020, and December 31, 2022. Propensity score matching was used to match patients who received NMV-r (NMV-r group) with those who did not receive NMV-r (control group). The primary outcome was all-cause hospitalization or death during the 30-day follow-up period. Two cohorts comprising 13 822 patients with balanced baseline characteristics were created using propensity score matching. During the follow-up period, the NMV-r group had a lower risk of all-cause hospitalization or death than the control group (1.4% [n = 193] vs. 3.1% [n = 434]; hazard ratio [HR], 0.497; 95% confidence interval [CI], 0.420-0.589). Compared with the control group, the NMV-r group also had a lower risk of all-cause hospitalization (HR, 0.606; 95% CI, 0.508-0.723) and all-cause mortality (HR, 0.076; 95% CI, 0.033-0.175). This lower risk was consistently observed in almost all subgroup analyses, which examined sex (male: 0.520 [0.401-0.675]; female: 0.586 [0.465-0.739]), age (age 18-64 years: 0.767 [0.601-0.980]; ≥65 years: 0.394 [0.308-0.505]), level of HbA1c (<7.5%: 0.490 [0.401-0.599]; ≥7.5%: 0.655 [0.441-0.972]), unvaccinated (0.466 [0.362-0.599]), type 1 DM (0.453 [0.286-0.718]) and type 2 DM (0.430 [0.361-0.511]). NMV-r can help reduce the risk of all-cause hospitalization or death in nonhospitalized patients with DM and COVID-19.

Constraints on Heavy Decaying Dark Matter from 570 Days of LHAASO Observations

The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 10^{5} and 10^{9}  GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.

The Hirsch-index in self-citation rates with articles in Medicine (Baltimore): Bibliometric analysis of publications in two stages from 2018 to 2021

BACKGROUND

The Hirsch-index (h-index) is a measure of academic productivity that incorporates both the quantity and quality of an author's output. However, it is still affected by self-citation behaviors. This study aims to determine the research output and self-citation rates (SCRs) in the Journal of Medicine (Baltimore), establishing a benchmark for bibliometrics, in addition to identifying significant differences between stages from 2018 to 2021.

METHODS

We searched the PubMed database to obtain 17,912 articles published between 2018 and 2021 in Medicine (Baltimore). Two parts were carried out to conduct this study: the categories were clustered according to the medical subject headings (denoted by midical subject headings [MeSH] terms) using social network analysis; 3 visualizations were used (choropleth map, forest plot, and Sankey diagram) to identify dominant entities (e.g., years, countries, regions, institutes, authors, categories, and document types); 2-way analysis of variance (ANOVA) was performed to differentiate outputs between entities and stages, and the SCR with articles in Medicine (Baltimore) was examined. SCR, as well as the proportion of self-citation (SC) in the previous 2 years in comparison to SC were computed.

RESULTS

We found that South Korea, Sichuan (China), and Beijing (China) accounted for the majority of articles in Medicine (Baltimore); ten categories were clustered and led by 3 MeSh terms: methods, drug therapy, and complications; and more articles (52%) were in the recent stage (2020-2021); no significant difference in counts was observed between the 2 stages based on the top ten entities using the forest plot (Z = 0.05, P = .962) and 2-way ANOVA (F = 0.09, P = .76); the SCR was 5.69% (<15%); the h-index did not differ between the 2 collections of self-citation inclusion and exclusion; and the SC in the previous 2 years accounted for 70% of the self-citation exclusion.

CONCLUSION

By visualizing the characteristics of a given journal, a breakthrough was made. Subject categories can be classified using MeSH terms. Future bibliographical studies are recommended to perform the 2-way ANOVA and then compare the outputs from 2 stages as well as the changes in h-indexes between 2 sets of self-citation inclusion and exclusion.

[The characteristics and risk factors of cardiovascular diseases and psychological status in science and technologyists]

Objectives: To investigate the prevalence and related factors of cardiovascular diseases (CVD) and psychological problems in Chinese science and technology workers. Methods: The investigation was organized and conducted by the Innovative and Development Institute of China Association of Senior Scientists and Technologists and Capital Medical University Affiliated Beijing Anzhen Hospital, and included science and technology workers from research institutions and medical institutions in China by random sampling methods through face-to-face and online questionnaire investigation from July 1, 2019 to March 31, 2021. Information including age, sex, work stress status, CVD history, sleep, depression, and anxiety were included in the questionnaire. Results: This survey included 14 552 subjects. Among them, 25.5% were suffered from CVD, 48.6% were with insomnia, 28.8% experienced depression/anxiety (including only depression, only anxiety, depression combined with anxiety), and 15.6% had CVD in combined with depression/anxiety. Taking those without CVD and depression/anxiety as reference group, multiple logistic regression analyses showed that work stress increased the risk of depression/anxiety in subjects without CVD (manageable work stress, OR=2.253, 95%CI 1.583-3.206, overwhelming work stress OR=7.899, 95%CI 5.094-12.250), and drinking increased the risk of CVD (OR=1.978, 95%CI 1.382-2.833). Moreover, overwhelming work stress (OR=4.012, 95%CI 2.515-6.399) and smoking (OR=2.342, 95%CI 1.603-3.421) increased the risk of depression/anxiety in subjects with CVD (all P<0.001). Conclusion: The high morbidities of depression/anxiety, CVD, and CVD in combination with depression/anxiety urge us to take actions to protect the heart and mental health of scientific and technological workers.

Observation of WWW Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector

This Letter reports the observation of WWW production and a measurement of its cross section using 139  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. Events with two same-sign leptons (electrons or muons) and at least two jets, as well as events with three charged leptons, are selected. A multivariate technique is then used to discriminate between signal and background events. Events from WWW production are observed with a significance of 8.0 standard deviations, where the expectation is 5.4 standard deviations. The inclusive WWW production cross section is measured to be 820±100 (stat)±80 (syst)  fb, approximately 2.6 standard deviations from the predicted cross section of 511±18  fb calculated at next-to-leading-order QCD and leading-order electroweak accuracy.

Exploring Lorentz Invariance Violation from Ultrahigh-Energy γ Rays Observed by LHAASO

Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is >10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.

Search for Lepton-Flavor Violation in Z-Boson Decays with τ Leptons with the ATLAS Detector

A search for lepton-flavor-violating Z→eτ and Z→μτ decays with pp collision data recorded by the ATLAS detector at the LHC is presented. This analysis uses 139  fb^{-1} of Run 2 pp collisions at sqrt[s]=13  TeV and is combined with the results of a similar ATLAS search in the final state in which the τ lepton decays hadronically, using the same data set as well as Run 1 data. The addition of leptonically decaying τ leptons significantly improves the sensitivity reach for Z→ℓτ decays. The Z→ℓτ branching fractions are constrained in this analysis to B(Z→eτ)<7.0×10^{-6} and B(Z→μτ)<7.2×10^{-6} at 95% confidence level. The combination with the previously published analyses sets the strongest constraints to date: B(Z→eτ)<5.0×10^{-6} and B(Z→μτ)<6.5×10^{-6} at 95% confidence level.

[Epidemiological characteristics of novel coronavirus pneumonia in Shijiazhuang, China]

Objective: To analyze the epidemiological characteristics of an outbreak of novel coronavirus pneumonia (COVID-19) in Shijiazhuang, Hebei Province in 2021 and to provide scientific basis for developing improved strategies to prevent and control the outbreak of COVID-19. Methods: Descriptive analysis of the outbreak of COVID-19 in Shijiazhuang, Hebei Province was performed with SPSS 21.0 and Excel software. The statistical analysis of the incubation period was performed using the rstan package in R4.0.4. Results: As of February 14^th 2021, a total of 942 local confirmed cases were reported in Hebei Province, 869 cases in Shijiazhuang, of which 847 cases were available for case information. This outbreak was mainly in rural areas, with the largest number of confirmed cases in Xiaoguozhuang village, 249 (29.4%); followed by Nanqiaozhai village, 128 (15.1%); and Liujiazuo village, 85 (10.0%). The outbreak lasted from January 2^nd, 2021 to February 14^th, 2021, and was mainly transmitted among the farmers as well as the students through dining parties, public gatherings and family contacts, showing an obvious time and occupation concentration trend. An analysis of 116 local confirmed cases in this outbreak with specific exposure time and onset time indicated that the median incubation period was 6 [interquartile range(IQR): 3.3, 10.0] days; whereas another report including 264 local confirmed cases with specific exposure time window showed that a median incubation period was 8.5 [95% confidence interval (CI): 1.8-18.8] days. Conclusions: This outbreak was mainly related to rural areas, and was associated with parties, public gatherings and family gatherings. Self-protection and isolation of key areas and populations at risk should be effectively implemented to avoid close contact and other measures to reduce the occurrence of COVID-19 aggregation. Based on the results of the incubation period of this outbreak, the isolation period could be recommended to be extended to three weeks.

Serum lactic acid level predicts poor myocardial perfusion and in-hospital outcomes in patients undergoing primary percutaneous coronary intervention

Background

Elevated serum lactic acid level is associated with poor outcomes in patients with critical diseases like shock. However, the clinical implication of this biomarker in patients with acute myocardial infarction remains unclear.

Purpose

We aimed to explore the predictive power of serum lactic acid level on admission for in-hospital outcomes in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention (pPCI).

Methods

Consecutive patients undergoing pPCI with available data on serum lactid acid level were evaluated for eligbility in this retrospective cohort study. The primary outcome was all-cause death during hospitalization. Enzymatic infarct size and major adverse cardiovascular events (MACE, defined as a combination of all-cause death, recurrent myocardial infarction, and unplanned repeated revascularization) were considered secondary outcomes. Independent preditors of in-hospital death were determined by multiple logisic regression analysis. Odds ratio (OR) with 95% confidence interval (CI) was used to demonstrate the association. The predictive power of serum latictic acid level for in-hospital death was evaluated through receiver operator characteristic curve, which generated C-statictic. A combination model was further constructed by adding serum latictic acid level to the Global Registry of Acute Coronary Events (GRACE) risk score (LA-GRACE risk score). The linear dependence between serum lactic acids level and othe clinical variables was analysed using Spearman rank correlation.

Results

Of the 302 patients enrolled in the current analysis, 15 (5.0%) died during hospitalization. Serum lactic acid level (OR=1.657, 95% CI: 1.115 to 2.463, p=0.012)and left ventricular ejection fraction (OR=0.858, 95% CI: 0.767 to 0.959, p=0.007) were the only two independent predictors of in-hospital death. The C-statistic of serum lactic acid level for predicting in-hospital death was 0.886 (95% CI: 0.793 to 0.979). The LA-GRACE risk score improved the C-statistic of the GRACE score from 0.898 to 0.911 (p=0.294), with continuous net reclassification improvement of 0.567 (p=0.023) and integrated discrimination improvement of 0.206 (p=0.003). High serum lactic acid level was also asscoiated with larger enzymatic infarct size (p=0.002) and MACE (p=0.004). Further, it significantly correlated with white blood cell counts (r=0.264, p&lt;0.001), serum creatinine level (r=0.189, p=0.001), and systolic blood pressure (r=−0.122, p=0.034).

Conclusion

Serum lactic acid level on admission is asscoiated with poor myocardial perfusion and in-hospital outcomes in patients with acute myocardial infarction undergoing pPCI. It may contribute to better risk stratification in these populations.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This study was supported by the National Program on Key Basic Research Project of China (Grant No: 2019YFC0840601 and 2014CBA02003), National Natural Science Foundation of China (Grant No: 81870267, 81970295, 81521001, 81670318 and 81570314), Grant of Shanghai Shenkang on Key Clinical Research Project (Grant No: SHDC2020CR2015A and SHDC12019104), Grant of Shanghai Science and Technology Committee (Grant No: 19MC1910300, 18411950200 and 20JC1410800), Key Medical and Health Projects of Xiamen Province (No: 3502Z20204004), Grant of Shanghai Municipal Commission of Health and Family Planning (Grant No: 2017YQ057), Grant of Zhongshan Hospital Affiliated to Fudan University (Grant No: 2018ZSLC01), VG Funding of Clinical Trials (2017-CCA-VG-036) and Merck Funding (Xinxin-merck-fund-051). ROC of lactic acid and GRACE score

Search for New Phenomena in Final States with Two Leptons and One or No b-Tagged Jets at sqrt[s]=13 TeV Using the ATLAS Detector

A search for new phenomena is presented in final states with two leptons and one or no b-tagged jets. The event selection requires the two leptons to have opposite charge, the same flavor (electrons or muons), and a large invariant mass. The analysis is based on the full run-2 proton-proton collision dataset recorded at a center-of-mass energy of sqrt[s]=13  TeV by the ATLAS experiment at the LHC, corresponding to an integrated luminosity of 139  fb^{-1}. No significant deviation from the expected background is observed in the data. Inspired by the B-meson decay anomalies, a four-fermion contact interaction between two quarks (b, s) and two leptons (ee or μμ) is used as a benchmark signal model, which is characterized by the energy scale and coupling, Λ and g_{*}, respectively. Contact interactions with Λ/g_{*} lower than 2.0 (2.4) TeV are excluded for electrons (muons) at the 95% confidence level, still far below the value that is favored by the B-meson decay anomalies. Model-independent limits are set as a function of the minimum dilepton invariant mass, which allow the results to be reinterpreted in various signal scenarios.

Search for Displaced Leptons in sqrt[s]=13 TeV pp Collisions with the ATLAS Detector

A search for charged leptons with large impact parameters using 139  fb^{-1} of sqrt[s]=13  TeV pp collision data from the ATLAS detector at the LHC is presented, addressing a long-standing gap in coverage of possible new physics signatures. Results are consistent with the background prediction. This search provides unique sensitivity to long-lived scalar supersymmetric lepton partners (sleptons). For lifetimes of 0.1 ns, selectron, smuon, and stau masses up to 720, 680, and 340  GeV, respectively, are excluded at 95% confidence level, drastically improving on the previous best limits from LEP.

Gamma-Ray Observation of the Cygnus Region in the 100-TeV Energy Region

We report observations of gamma-ray emissions with energies in the 100-TeV energy region from the Cygnus region in our Galaxy. Two sources are significantly detected in the directions of the Cygnus OB1 and OB2 associations. Based on their positional coincidences, we associate one with a pulsar PSR J2032+4127 and the other mainly with a pulsar wind nebula PWN G75.2+0.1, with the pulsar moving away from its original birthplace situated around the centroid of the observed gamma-ray emission. This work would stimulate further studies of particle acceleration mechanisms at these gamma-ray sources.

Peta-electron volt gamma-ray emission from the Crab Nebula

The Crab Nebula is a bright source of gamma rays powered by the Crab Pulsar's rotational energy through the formation and termination of a relativistic electron-positron wind. We report the detection of gamma rays from this source with energies from 5 × 10^-4 to 1.1 peta-electron volts with a spectrum showing gradual steepening over three energy decades. The ultrahigh-energy photons imply the presence of a peta-electron volt electron accelerator (a pevatron) in the nebula, with an acceleration rate exceeding 15% of the theoretical limit. We constrain the pevatron's size between 0.025 and 0.1 parsecs and the magnetic field to ≈110 microgauss. The production rate of peta-electron volt electrons, 2.5 × 10³⁶ ergs per second, constitutes 0.5% of the pulsar spin-down luminosity, although we cannot exclude a contribution of peta-electron volt protons to the production of the highest-energy gamma rays.

Extended Very-High-Energy Gamma-Ray Emission Surrounding PSR J0622+3749 Observed by LHAASO-KM2A

We report the discovery of an extended very-high-energy (VHE) gamma-ray source around the location of the middle-aged (207.8 kyr) pulsar PSR J0622+3749 with the Large High-Altitude Air Shower Observatory (LHAASO). The source is detected with a significance of 8.2σ for E>25  TeV assuming a Gaussian template. The best-fit location is (right ascension, declination) =(95.47°±0.11°,37.92°±0.09°), and the extension is 0.40°±0.07°. The energy spectrum can be described by a power-law spectrum with an index of -2.92±0.17_{stat}±0.02_{sys}. No clear extended multiwavelength counterpart of the LHAASO source has been found from the radio to sub-TeV bands. The LHAASO observations are consistent with the scenario that VHE electrons escaped from the pulsar, diffused in the interstellar medium, and scattered the interstellar radiation field. If interpreted as the pulsar halo scenario, the diffusion coefficient, inferred for electrons with median energies of ∼160  TeV, is consistent with those obtained from the extended halos around Geminga and Monogem and much smaller than that derived from cosmic ray secondaries. The LHAASO discovery of this source thus likely enriches the class of so-called pulsar halos and confirms that high-energy particles generally diffuse very slowly in the disturbed medium around pulsars.