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1.
Accid Anal Prev ; 206: 107715, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38996532

ABSTRACT

Virtual reality (VR) simulation offers a proactive, cost effective, immersive, and low risk platform for studying pedestrian safety. Within immersive virtual environments (IVEs), existing and alternative design conditions and intelligent transportation systems (ITS) technologies can be directly compared, prior to real-world implementation, to assess the impacts alternatives may have on pedestrian safety, perception, and behavior. Environmental factors can be controlled within IVEs so that test trials are replicable and directly comparable. Coupled with stated preference feedback, participants' observed preferences and behavior provide a comprehensive understanding of the impacts of proposed design alternatives. This research presents a case study of pedestrian behavior with three different mid-block crossing safety treatments modeled within a one-to-one scale IVE replication of a real-world location in Charlottesville, Virginia. The three safety treatments consider both passive and active collision avoidance designs and technologies, including (1) the existing painted crosswalk, (2) the addition of rectangular rapid flashing beacons (RRFBs), and (3) a pedestrian to everything (P2X) ITS phone application. Additionally, this paper demonstrates a VR simulation experimental design and framework for testing pedestrian safety treatments within naturalistic and replicable IVEs to assess both stated and observed preferences and behaviors of pedestrians. Repeated measures ANOVA indicated changes in both accepted gap size (p = 0.001) and crossing speed (p < 0.001) with alternative safety treatments. Generalized mixed models showed that pedestrians waited for statistically larger gap sizes (p = 0.02) without the assistance of alternative safety technologies (RRFBs and P2X application) and pedestrians crossed the street significantly faster (p = 0.001) without the alternative safety technologies, leading to unsafe dashing behavior. Through post-experiment surveys, it was found that participants perceived the As Built environment to be the least safe of the three treatments and that their sense of risk within the IVE was realistic. Considering both the observed crossing behavior and stated feedback, pedestrians exhibited intentionally unsafe darting behavior without assistive safety technology. This study demonstrates how VR simulation may be leveraged to study both stated preferences and observed behavior for understanding the safety implications of alternative roadway designs, providing a proactive approach for assessing and designing for pedestrian safety.

2.
Benef Microbes ; 15(4): 357-371, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38955353

ABSTRACT

Constipation during pregnancy can induce serious complications, including miscarriage and preterm labour, while the evidence of probiotics in improving constipation during pregnancy was little. In this study, 29 healthy pregnant women and 65 constipated pregnant women were enrolled to assess the effectiveness of probiotics on constipation during pregnancy. Our results showed that the probiotics were effective in improving the Constipation Severity Scale (CSS) and Bristol Stool Scale (BSS) scores, including increasing defecation frequency, decreasing defecation time, and improving fecal characteristics. 16S rRNA sequencing revealed that the probiotics effectively restored the diversity of intestinal microbiota. At the phylum level, Firmicutes (13.27% vs 57.20%) and Actinobacteria (3.77% vs 12.80%) were increased, while Bacteroidetes (77.82% vs 20.24%) was decreased. At the level of the genus, Faecalibacterium (2.03% vs 10.33%), Bifidobacterium (1.21% vs 8.56%), and Phascolarctobacterium (0.05% vs 2.88%), the beneficial bacteria were increased, while the Bacteroides (29.23% vs 12.28%) and Prevotella (24.32% vs 4.92%) were decreased. In conclusion, these results indicated that probiotics can effectively relieve the constipation symptoms by improving the diversity of intestinal microbiota, regulating the disturbance of microflorae, and restoring the balance of microflorae to exert a stronger moderating effect than diet and lifestyle modification. Our results provided clinical data and a theoretical basis for the exploitation of probiotics in treating constipation during pregnancy. Chinese Clinical Trial Registry: ChiCTR2100052069.


Subject(s)
Constipation , Feces , Gastrointestinal Microbiome , Probiotics , RNA, Ribosomal, 16S , Constipation/therapy , Constipation/microbiology , Constipation/drug therapy , Humans , Female , Probiotics/administration & dosage , Probiotics/therapeutic use , Pregnancy , Gastrointestinal Microbiome/drug effects , Adult , Feces/microbiology , RNA, Ribosomal, 16S/genetics , Bacteria/classification , Bacteria/genetics , Bacteria/drug effects , Bacteria/isolation & purification , Pregnancy Complications/microbiology , Pregnancy Complications/therapy , Pregnancy Complications/drug therapy , Young Adult , Defecation/drug effects
4.
Zhonghua Yan Ke Za Zhi ; 60(7): 601-610, 2024 Jul 11.
Article in Chinese | MEDLINE | ID: mdl-38955762

ABSTRACT

Objective: To investigate the characteristics of posterior segment lesions in Marfan syndrome (MFS) patients and their relationship with anterior segment biometric parameters and FBN1 genotype. Methods: A cross-sectional study was conducted. A total of 121 MFS patients, 76 males and 45 females, with an average age of (11.72±11.66) years, who visited the Department of Ophthalmology, Eye & ENT Hospital of Fudan University from January 2013 to March 2023 were included. The presence of posterior scleral staphyloma was observed using B-mode ultrasound, and macular lesions were identified and classified using the atrophy-traction-neovascularization system based on ultra-widefield fundus images, color fundus images, and optical coherence tomography scans. Anterior segment biometric parameters, including axial length of the eye, average corneal curvature, corneal astigmatism, horizontal corneal diameter, anterior chamber depth, and lens thickness, were collected, and the direction and extent of lens dislocation were observed. Molecular genetic analysis of FBN1 gene mutations in patients was performed using next-generation sequencing based on a panel of ocular genetic diseases, and the impact of the genotype and anterior segment biometric parameters on the posterior segment manifestations was analyzed. Results: Sixty patients exhibited posterior segment lesions, including retinal detachment (4 cases, 3.31%), macular lesions (47 cases, 38.84%), and posterior scleral staphyloma (54 cases, 44.63%). There was statistically significant difference in axial length of the eye between patients with and without posterior scleral staphyloma [23.09 (22.24, 24.43) and 27.04 (25.44, 28.88) mm], between patients with and without macular lesions [23.16 (22.24, 24.61) and 27.04 (25.74, 28.78) mm], and between patients with and without atrophic macular lesions [23.16 (22.24, 24.61) and 27.04 (25.74, 28.79) mm] (all P<0.001). There was statistically significant difference in anterior chamber depth between patients with and without macular lesions [3.11 (2.75, 3.30) and 3.34 (3.09, 3.60) mm] (P<0.05). There was also statistically significant difference in corneal astigmatism between patients with and without posterior scleral staphyloma [2.15 (1.20, 2.93) and 1.40 (1.00, 2.20) diopters] (P<0.05). The location and region of the FBN1 gene mutation not only showed statistically significant difference from the positive rates of posterior scleral staphyloma and macular lesions (all P<0.05), but also influenced the occurrence of atrophic macular lesions (both P<0.05). Patients with FBN1 mutations located in the transforming growth factor ß regulatory sequence had the highest proportion of posterior scleral staphyloma and macular lesions (both 10/11). Conclusions: Posterior scleral staphyloma and macular lesions have a relatively high incidence in MFS patients and tend to progress to more severe grades. The age, axial length of the eye, anterior chamber depth, corneal astigmatism, and location and region of the FBN1 gene mutation are factors affecting the posterior segment lesions in MFS patients.


Subject(s)
Fibrillin-1 , Genotype , Marfan Syndrome , Humans , Male , Female , Fibrillin-1/genetics , Cross-Sectional Studies , Marfan Syndrome/genetics , Child , Adolescent , Anterior Eye Segment , Posterior Eye Segment/pathology , Mutation , Biometry , Young Adult , Macular Degeneration/genetics , Adipokines
5.
Phys Rev Lett ; 132(23): 231902, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38905649

ABSTRACT

Using (10.087±0.044)×10^{9} J/ψ events collected with the BESIII detector at the BEPCII storage ring, the processes Λp→Λp and Λ[over ¯]p→Λ[over ¯]p are studied, where the Λ/Λ[over ¯] baryons are produced in the process J/ψ→ΛΛ[over ¯] and the protons are the hydrogen nuclei in the cooling oil of the beam pipe. Clear signals are observed for the two reactions. The cross sections in -0.9≤cosθ_{Λ/Λ[over ¯]}≤0.9 are measured to be σ(Λp→Λp)=(12.2±1.6_{stat}±1.1_{syst}) and σ(Λ[over ¯]p→Λ[over ¯]p)=(17.5±2.1_{stat}±1.6_{syst}) mb at the Λ/Λ[over ¯] momentum of 1.074 GeV/c within a range of ±0.017 GeV/c, where the θ_{Λ/Λ[over ¯]} are the scattering angles of the Λ/Λ[over ¯] in the Λp/Λ[over ¯]p rest frames. Furthermore, the differential cross sections of the two reactions are also measured, where there is a slight tendency of forward scattering for Λp→Λp, and a strong forward peak for Λ[over ¯]p→Λ[over ¯]p. We present an approach to extract the total elastic cross sections by extrapolation. The study of Λ[over ¯]p→Λ[over ¯]p represents the first study of antihyperon-nucleon scattering, and these new measurements will serve as important inputs for the theoretical understanding of the (anti)hyperon-nucleon interaction.

6.
Nan Fang Yi Ke Da Xue Xue Bao ; 44(5): 904-912, 2024 May 20.
Article in Chinese | MEDLINE | ID: mdl-38862448

ABSTRACT

OBJECTIVE: To explore the effect of pristimerin combined with cisplatin on proliferation and apoptosis of nasopharyngeal carcinoma cells. METHODS: CCK-8 assay was used to examine the survival rate of HNE-1 and CNE-2Z cells following treatment for 24 h with different concentrations of pristimerin, cisplatin or their combination. The changes in colony formation ability, apoptosis, and intracellular reactive oxygen species (ROS) levels of the treated cells were analyzed using colony formation assay and flow cytometry. Western blotting was performed to detect the changes in protein expressions in the cells. The effects of pre-treatment with NAC on proliferation, apoptosis, and PI3K/AKT signaling pathway were observed in pristimerin- and/or cisplatin-treated cells. RESULTS: Both pristimerin and cisplatin significantly lowered the survival rate of HNE-1 and CNE-2Z cells (P < 0.05). Compared with pristimerin or cisplatin alone, their combination more strongly inhibited survival and colony formation ability of the cells, increased cell apoptosis rate and intracellular ROS levels, upregulated the protein expressions of Bax, cleaved caspase-3, and cleaved PARP, and downregulated the protein expressions of Bcl-2, Mcl-1, PARP and p-PI3K and p-AKT (P < 0.05). NAC pretreatment significantly attenuated proliferation inhibition and apoptosis-promoting effects of pristimerin combined with cisplatin, and partially restored the downregulated protein expressions of p-PI3K and p-AKT in HNE-1 and CNE-2Z cells with the combined treatment (P < 0.05). CONCLUSION: Pristimerin can enhance cisplatin-induced proliferation inhibition and apoptosis in nasopharyngeal carcinoma cells, the mechanism of which may involve ROS-mediated deactivation of the PI3K/AKT signaling pathway.


Subject(s)
Apoptosis , Cell Proliferation , Cisplatin , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Reactive Oxygen Species , Signal Transduction , Humans , Cisplatin/pharmacology , Apoptosis/drug effects , Nasopharyngeal Carcinoma/metabolism , Nasopharyngeal Carcinoma/pathology , Proto-Oncogene Proteins c-akt/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Signal Transduction/drug effects , Reactive Oxygen Species/metabolism , Cell Line, Tumor , Nasopharyngeal Neoplasms/metabolism , Nasopharyngeal Neoplasms/pathology , Cell Proliferation/drug effects , Pentacyclic Triterpenes/pharmacology , Triterpenes/pharmacology
7.
Nan Fang Yi Ke Da Xue Xue Bao ; 44(5): 851-858, 2024 May 20.
Article in Chinese | MEDLINE | ID: mdl-38862442

ABSTRACT

OBJECTIVE: To develop an intelligent model for differential diagnosis of atrioventricular nodal re-entrant tachycardia (AVNRT) and atrioventricular re-entrant tachycardia (AVRT) using 12-lead wearable electrocardiogram devices. METHODS: A total of 356 samples of 12-lead supraventricular tachycardia (SVT) electrocardiograms recorded by wearable devices were randomly divided into training and validation sets using 5-fold cross validation to establish the intelligent classification model, and 101 patients with the diagnosis of SVT undergoing electrophysiological studies and radiofrequency ablation from October, 2021 to March, 2023 were selected as the testing set. The changes in electrocardiogram parameters before and during induced tachycardia were compared. Based on multiscale deep neural network, an intelligent diagnosis model for classifying SVT mechanisms was constructed and validated. The 3-lead electrocardiogram signals from Ⅱ, Ⅲ, and Ⅴ1 were extracted to build new classification models, whose diagnostic efficacy was compared with that of the 12-lead model. RESULTS: Of the 101 patients with SVT in the testing set, 68 were diagnosed with AVNRT and 33 were diagnosed with AVRT by electrophysiological study. The pre-trained model achieved a high area under the precision-recall curve (0.9492) and F1 score (0.8195) for identifying AVNRT in the validation set. The total F1 scores of the lead Ⅱ, Ⅲ, Ⅴ1, 3-lead and 12-lead intelligent diagnostic models in the testing set were 0.5597, 0.6061, 0.3419, 0.6003 and 0.6136, respectively. Compared with the 12-lead classification model, the lead-Ⅲ model had a net reclassification index improvement of -0.029 (P=0.878) and an integrated discrimination index improvement of -0.005 (P=0.965). CONCLUSION: The intelligent diagnostic model based on multiscale deep neural network using wearable electrocardiogram devices has an acceptable accuracy for classifying SVT mechanisms.


Subject(s)
Electrocardiography , Tachycardia, Supraventricular , Wearable Electronic Devices , Humans , Electrocardiography/methods , Electrocardiography/instrumentation , Tachycardia, Supraventricular/diagnosis , Tachycardia, Supraventricular/classification , Tachycardia, Supraventricular/physiopathology , Diagnosis, Differential , Tachycardia, Atrioventricular Nodal Reentry/diagnosis , Tachycardia, Atrioventricular Nodal Reentry/classification , Tachycardia, Atrioventricular Nodal Reentry/physiopathology , Neural Networks, Computer , Female , Male
8.
Clin Radiol ; 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38945793

ABSTRACT

Spinal muscular atrophy (SMA) is an autosomal recessive genetic disease caused by the degeneration of the α-motor neurons in the anterior horn of the spinal cord. SMA is clinically characterized by progressive and symmetrical muscle weakness and muscle atrophy and ends up with systemic multisystem abnormalities. Quantitative MRI (qMRI) has the advantages of non-invasiveness, objective sensitivity, and high reproducibility, and has important clinical value in evaluating the severity of neuromuscular diseases and monitoring the efficacy of treatment. This article summarizes the clinical use of muscular MRI and magnetic resonance neurography in assessing the progress of SMA.

9.
J Knee Surg ; 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38870991

ABSTRACT

Outpatient total knee arthroplasty (TKA) is being performed more frequently in ambulatory surgical centers (ASCs) to decrease the cost of care. Discharge pathways include 23-hour observation (OBSERVATION) or same-day discharge home (HOME), which differ in postoperative medical supervision. Few studies allow patients to self-select their discharge pathway. This study compared patient variables between self-selected OBSERVATION or HOME discharge after TKA at an ASC. We hypothesized that age, sex, and distance lived from the ASC would differ between discharge pathways. Clinical and patient-reported outcomes were explored.A chart review identified 130 patients with TKA at an ASC between November 2017 and December 2019. Patients self-selected OBSERVATION or HOME during a preoperative physician visit. Patient variables obtained from the electronic medical record were age, sex, race/ethnicity, marital status, body mass index, diabetic status, American Society of Anesthesiologists (ASA) class, distance lived from the ASC, anesthesia type, procedure time, and time in the postanesthesia recovery unit. Clinical outcomes (knee range of motion, infection rate, and reoperation rate) and patient-reported outcomes (Knee Injury and Osteoarthritis Outcome Score, Joint Replacement [KOOS, JR]; Oxford Knee Score [OKS]) were collected at either 6 or 12 weeks postsurgery. Variables were compared between groups.Pathway selection was n = 70 OBSERVATION and n = 60 HOME, and all patients completed their self-selected discharge pathway. Age and proportion of females were significantly higher in OBSERVATION than in HOME (61.3 ± 3.5 vs. 58.5 ± 5.4 years, 85.7 vs. 65.0%, respectively; p < 0.05). Distance lived from the ASC tended to be greater in OBSERVATION than HOME (22.1 ± 24.6 vs. 15.3 ± 10.1 miles, p = 0.056). Across groups, clinical outcomes were favorable (i.e., >88% met the 6-week knee flexion milestone, 1.9% infection rate, and 3.1% manipulation under anesthesia), and the preoperative to 12-week postoperative change in KOOS, JR and OKS scores met the minimal clinically important difference.Older age, female sex, and farther distance lived from the ASC may influence patients to select OBSERVATION over HOME discharge following TKA at an ASC. No robust differences were found in early outcomes.

10.
Zhonghua Liu Xing Bing Xue Za Zhi ; 45(6): 779-786, 2024 Jun 10.
Article in Chinese | MEDLINE | ID: mdl-38889976

ABSTRACT

Objective: To describe the distribution of lipoprotein (a) [Lp(a)] levels in non-arteriosclerotic cardiovascular disease (ASCVD) population in China and explore its influencing factors. Methods: This study was based on a nested case-control study in the CKB study measured plasma biomarkers. Lp(a) levels was measured using a polyclonal antibody-based turbidimetric assay certified by the reference laboratory and ≥75.0 nmol/L defined as high Lp(a). Multiple logistic regression model was used to examine the factors related to Lp(a) levels. Results: Among the 5 870 non-ASCVD population included in the analysis, Lp(a) levels showed a right-skewed distribution, with a M (Q1, Q3) of 17.5 (8.8, 43.5) nmol/L. The multiple logistic regression analysis found that female was associated with high Lp(a) (OR=1.23, 95%CI: 1.05-1.43). The risk of increased Lp(a) levels in subjects with abdominal obesity was significantly reduced (OR=0.68, 95%CI: 0.52-0.89). As TC, LDL-C, apolipoprotein A1(Apo A1), and apolipoprotein B(Apo B) levels increased, the risk of high Lp(a) increased, with OR (95%CI) for each elevated group was 2.40 (1.76-3.24), 2.68 (1.36-4.93), 1.29 (1.03-1.61), and 1.65 (1.27-2.13), respectively. The risk of high Lp(a) was reduced in the HDL-C lowering group with an OR (95%CI) of 0.76 (0.61-0.94). In contrast, an increase in TG levels and the ratio of Apo A1/Apo B(Apo A1/B) was negatively correlated with the risk of high Lp(a), with OR (95%CI) of 0.73 (0.60-0.89) for elevated triglyceride group, and OR (95%CI) of 0.60 (0.50-0.72) for the Apo A1/B ratio increase group (linear trend test P≤0.001 except for Apo A1). However, no correlation was found between Lp(a) levels and lifestyle factors such as diet, smoking, and physical activity. Conclusions: Lp(a) levels were associated with sex and abdominal obesity, but less with lifestyle behaviors.


Subject(s)
Cardiovascular Diseases , Lipoprotein(a) , Humans , Lipoprotein(a)/blood , China/epidemiology , Case-Control Studies , Female , Cardiovascular Diseases/blood , Cardiovascular Diseases/epidemiology , Male , Risk Factors , Logistic Models , Biomarkers/blood , Middle Aged
11.
ESMO Open ; 9(5): 102974, 2024 May.
Article in English | MEDLINE | ID: mdl-38796284

ABSTRACT

The European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with early breast cancer were updated and published online in 2023, and adapted, according to previously established standard methodology, to produce the Pan-Asian adapted (PAGA) ESMO consensus guidelines for the management of Asian patients with early breast cancer. The adapted guidelines presented in this manuscript represent the consensus opinions reached by a panel of Asian experts in the treatment of patients with breast cancer representing the oncological societies of China (CSCO), Indonesia (ISHMO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), the Philippines (PSMO), Singapore (SSO), Taiwan (TOS) and Thailand (TSCO), co-ordinated by ESMO and KSMO. The voting was based on scientific evidence and was independent of the current treatment practices, drug access restrictions and reimbursement decisions in the different Asian regions represented by the 10 oncological societies. The latter are discussed separately in the manuscript. The aim is to provide guidance for the optimisation and harmonisation of the management of patients with early breast cancer across the different regions of Asia, drawing on the evidence provided by both Western and Asian trials, whilst respecting the differences in screening practices, molecular profiling, as well as the age and stage at presentation. Attention is drawn to the disparity in the drug approvals and reimbursement strategies, between the different regions of Asia.


Subject(s)
Breast Neoplasms , Humans , Breast Neoplasms/therapy , Breast Neoplasms/diagnosis , Female , Asia/epidemiology , Medical Oncology/standards , Practice Guidelines as Topic , Neoplasm Staging
12.
Phys Rev Lett ; 132(18): 181901, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38759175

ABSTRACT

Based on (10087±44)×10^{6} J/ψ events collected with the BESIII detector, a partial wave analysis of the decay J/ψ→γK_{S}^{0}K_{S}^{0}η^{'} is performed. The mass and width of the X(2370) are measured to be 2395±11(stat)_{-94}^{+26}(syst) MeV/c^{2} and 188_{-17}^{+18}(stat)_{-33}^{+124}(syst) MeV, respectively. The corresponding product branching fraction is B[J/ψ→γX(2370)]×B[X(2370)→f_{0}(980)η^{'}]×B[f_{0}(980)→K_{S}^{0}K_{S}^{0}]=(1.31±0.22(stat)_{-0.84}^{+2.85}(syst))×10^{-5}. The statistical significance of the X(2370) is greater than 11.7σ and the spin parity is determined to be 0^{-+} for the first time. The measured mass and spin parity of the X(2370) are consistent with the predictions of the lightest pseudoscalar glueball.

13.
Phys Rev Lett ; 132(16): 161901, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38701481

ABSTRACT

We present measurements of the Born cross sections for the processes e^{+}e^{-}→ωχ_{c1} and ωχ_{c2} at center-of-mass energies sqrt[s] from 4.308 to 4.951 GeV. The measurements are performed with data samples corresponding to an integrated luminosity of 11.0 fb^{-1} collected with the BESIII detector operating at the Beijing Electron Positron Collider storage ring. Assuming the e^{+}e^{-}→ωχ_{c2} signals come from a single resonance, the mass and width are determined to be M=(4413.6±9.0±0.8) MeV/c^{2} and Γ=(110.5±15.0±2.9) MeV, respectively, which is consistent with the parameters of the well-established resonance ψ(4415). In addition, we also use one single resonance to describe the e^{+}e^{-}→ωχ_{c1} line shape and determine the mass and width to be M=(4544.2±18.7±1.7) MeV/c^{2} and Γ=(116.1±33.5±1.7) MeV, respectively. The structure of this line shape, observed for the first time, requires further understanding.

14.
Phys Rev Lett ; 132(19): 191902, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38804946

ABSTRACT

We report the measurement of the inclusive cross sections for e^{+}e^{-}→nOCH (where nOCH denotes non-open charm hadrons) with improved precision at center-of-mass (c.m.) energies from 3.645 to 3.871 GeV. We observe three resonances: R(3760), R(3780), and R(3810) with significances of 8.1σ, 13.7σ, and 8.8σ, respectively. The R(3810) state is observed for the first time, while the R(3760) and R(3780) states are observed for the first time in the nOCH cross sections. Two sets of resonance parameters describe the energy-dependent line shape of the cross sections well. In set I [set II], the R(3810) state has mass (3805.7±1.1±2.7) [(3805.7±1.1±2.7)] MeV/c^{2}, total width (11.6±2.9±1.9) [(11.5±2.8±1.9)] MeV, and an electronic width multiplied by the nOCH decay branching fraction of (10.9±3.8±2.5) [(11.0±3.4±2.5)] eV. In addition, we measure the branching fractions B[R(3760)→nOCH]=(25.2±16.1±30.4)%[(6.4±4.8±7.7)%] and B[R(3780)→nOCH]=(12.3±6.6±8.3)%[(10.4±4.8±7.0)%] for the first time. The R(3760) state can be interpreted as an open-charm (OC) molecular state, but containing a simple four-quark state component. The R(3810) state can be interpreted as a hadrocharmonium state.

15.
Phys Rev Lett ; 132(13): 131901, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38613263

ABSTRACT

We present cross sections for the reaction e^{+}e^{-}→K_{S}^{0}K_{L}^{0} at center-of-mass energies ranging from 3.51 to 4.95 GeV using data samples collected in the BESIII experiment, corresponding to a total integrated luminosity of 26.5 fb^{-1}. The ratio of neutral-to-charged kaon form factors at large momentum transfers (12

16.
Phys Rev Lett ; 132(13): 131002, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38613275

ABSTRACT

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.

17.
Phys Rev Lett ; 132(13): 131903, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38613307

ABSTRACT

We perform for the first time an amplitude analysis of the decay D^{+}→K_{S}^{0}π^{+}η and report the observation of the decay D^{+}→K_{S}^{0}a_{0}(980)^{+} using 2.93 fb^{-1} of e^{+}e^{-} collision data taken at a center-of-mass energy of 3.773 GeV with the BESIII detector. As the only W-annihilation-free decay among D to a_{0}(980) pseudoscalar, D^{+}→K_{S}^{0}a_{0}(980)^{+} is the ideal decay in extracting the contributions of the W-emission amplitudes involving a_{0}(980) and to study the final-state interactions. The absolute branching fraction of D^{+}→K_{S}^{0}π^{+}η is measured to be (1.27±0.04_{stat}±0.03_{syst})%. The branching fractions of intermediate processes D^{+}→K_{S}^{0}a_{0}(980)^{+} with a_{0}(980)^{+}→π^{+}η and D^{+}→π^{+}K[over ¯]_{0}^{*}(1430)^{0} with K[over ¯]_{0}^{*}(1430)^{0}→K_{S}^{0}η are measured to be (1.33±0.05_{stat}±0.04_{syst})% and (0.14±0.03_{stat}±0.01_{syst})%, respectively.

18.
Phys Rev Lett ; 132(14): 141901, 2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38640399

ABSTRACT

Using e^{+}e^{-} collision data corresponding to an integrated luminosity of 7.33 fb^{-1} recorded by the BESIII detector at center-of-mass energies between 4.128 and 4.226 GeV, we present an analysis of the decay D_{s}^{+}→π^{+}π^{-}e^{+}ν_{e}, where the D_{s}^{+} is produced via the process e^{+}e^{-}→D_{s}^{*±}D_{s}^{∓}. We observe the f_{0}(980) in the π^{+}π^{-} system and the branching fraction of the decay D_{s}^{+}→f_{0}(980)e^{+}ν_{e} with f_{0}(980)→π^{+}π^{-} measured to be (1.72±0.13_{stat}±0.10_{syst})×10^{-3}, where the uncertainties are statistical and systematic, respectively. The dynamics of the D_{s}^{+}→f_{0}(980)e^{+}ν_{e} decay are studied with the simple pole parametrization of the hadronic form factor and the Flatté formula describing the f_{0}(980) in the differential decay rate, and the product of the form factor f_{+}^{f_{0}}(0) and the c→s Cabibbo-Kobayashi-Maskawa matrix element |V_{cs}| is determined for the first time to be f_{+}^{f_{0}}(0)|V_{cs}|=0.504±0.017_{stat}±0.035_{syst}. Furthermore, the decay D_{s}^{+}→f_{0}(500)e^{+}ν_{e} is searched for the first time but no signal is found. The upper limit on the branching fraction of D_{s}^{+}→f_{0}(500)e^{+}ν_{e}, f_{0}(500)→π^{+}π^{-} decay is set to be 3.3×10^{-4} at 90% confidence level.

19.
Phys Rev Lett ; 132(15): 151903, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38682963

ABSTRACT

We perform a study of the χ_{c1}(3872) line shape using the data samples of e^{+}e^{-}→γχ_{c1}(3872), χ_{c1}(3872)→D^{0}D[over ¯]^{0}π^{0}, and π^{+}π^{-}J/ψ collected with the BESIII detector. The effects of the coupled channels and the off-shell D^{*0} are included in the parametrization of the line shape. The line shape mass parameter is obtained to be M_{X}=(3871.63±0.13_{-0.05}^{+0.06}) MeV. Two poles are found on the first and second Riemann sheets corresponding to the D^{*0}D[over ¯]^{0} branch cut. The pole location on the first sheet is much closer to the D^{*0}D[over ¯]^{0} threshold than the other, and is determined to be 7.04±0.15_{-0.08}^{+0.07} MeV above the D^{0}D[over ¯]^{0}π^{0} threshold with an imaginary part -0.19±0.08_{-0.19}^{+0.14} MeV.

20.
Phys Rev Lett ; 132(15): 151901, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38682972

ABSTRACT

Using a sample of (10087±44)×10^{6} J/ψ events, which is about 45 times larger than that was previously analyzed, a further investigation on the J/ψ→γ3(π^{+}π^{-}) decay is performed. A significant distortion at 1.84 GeV/c^{2} in the line shape of the 3(π^{+}π^{-}) invariant mass spectrum is observed for the first time, which could be resolved by two overlapping resonant structures, X(1840) and X(1880). The new state X(1880) is observed with a statistical significance larger than 10σ. The mass and width of X(1880) are determined to be 1882.1±1.7±0.7 MeV/c^{2} and 30.7±5.5±2.4 MeV, respectively, which indicates the existence of a pp[over ¯] bound state.

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