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Neoplasias Encefálicas , Proteínas de Ligação a RNA , Humanos , Masculino , Feminino , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/genética , Pré-Escolar , Estudos Retrospectivos , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteína Glial Fibrilar Ácida/metabolismo , Proteína Glial Fibrilar Ácida/genética , Nestina/metabolismo , Nestina/genética , Lobo Parietal/patologia , Lobo Parietal/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas Cromossômicas não Histona/metabolismo , Proteínas Cromossômicas não Histona/genética , Neoplasias do Tronco Encefálico/patologia , Neoplasias do Tronco Encefálico/genética , Neoplasias do Tronco Encefálico/metabolismo , Neoplasias do Tronco Encefálico/cirurgia , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteína SMARCB1/metabolismo , Proteína SMARCB1/genética , Lobo Frontal/patologia , Lobo Frontal/metabolismo , Formação de Roseta , Seguimentos , Antígeno Ki-67/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genéticaRESUMO
Objective: To investigate the clinicopathological characteristics, immunophenotypes, molecular features, and differential diagnosis of BAP1 mutated clear cell renal cell carcinoma (CCRCC) for better understanding this entity. Methods: Clinical data, histological morphology, immunophenotypes and molecular characteristics of 18 BAP1 mutated CCRCC cases diagnosed at the Department of Pathology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China from January 2020 to December 2022 were analyzed. The patients were followed up. Results: There were 17 males and 1 female patients, aged from 39 to 72 years, with an average age of 56.3 years. Sixteen patients with primary CCRCC were followed up for an average of 24 months, 7 patients had metastases occurred from 4 to 22 months postoperatively. Thirteen of the 16 patients were alive at the time of the last follow-up while 3 patients died 12, 15, and 20 months after the surgery, respectively. One patient underwent retroperitoneal mass resection, but had lung metastasis 32 months after surgery. One case received cervical tumor resection and died at 22 months after the surgery. Characteristic CCRCC regions were identified in 11 of the 18 cases. The tumor cells were arranged in papillary, alveolar, and large nest patterns. Abundant lymphoid tissue, necrosis, and psammoma bodies were seen. Tumor cells showed abundant eosinophilic cytoplasm, and sometimes exhibited rhabdoid differentiation. Round eosinophilic globules were located in the cytoplasm and extracellular matrix. There were 9 cases with WHO/International Society of Urological Pathology grade 3, and 9 cases with grade 4. PAX8 (18/18), carbonic anhydrase 9 (CA9, 16/18), CD10 (18/18), and vimentin (18/18) were positive in the vast majority of tumors.TFE3 was expressed in 5 cases, with strong expression in only 1 case. Eighteen cases were all positive for P504s. Twelve cases harbored a BAP1 mutation combined with von Hippel-Lindau (VHL) mutation, and 2 cases had mutations in BAP1, VHL and PBRM1 simultaneously. SETD2 mutation was not found in any of the cases. Conclusions: BAP1 mutated CCRCC contained papillary, alveolar, and large nest patterns, eosinophilic cytoplasm, high-grade nucleoli, and collagen globules, with P504s positivity. In practical work, when encountering CCRCC containing these features, pathologists should consider the possibility of BAP1 mutations and conduct related molecular tests.
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Carcinoma de Células Renais , Neoplasias Renais , Mutação , Proteínas Supressoras de Tumor , Ubiquitina Tiolesterase , Humanos , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/cirurgia , Carcinoma de Células Renais/metabolismo , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Neoplasias Renais/genética , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Idoso , Adulto , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Fator de Transcrição PAX8/genética , Fator de Transcrição PAX8/metabolismo , Diagnóstico DiferencialRESUMO
The data of 57 renal cyst patients who visited the First Affiliated Hospital of Zhengzhou University from January 2023 to March 2024 were retrospectively analyzed. The age of patients ranged from three months to 60 years old, with 31 males and 26 females. The whole exome sequencing (WES) detected pathogenic or suspected pathogenic (P/LP) variants in 48 renal cystic probands, with a detection rate of 84.2% (48/57), including PKD1, PKD2, PKHD1, LRP5, COL4A4 and ALG8 gene variants as well as copy number variations (CNV). In addition, four PKD1 gene variants of uncertain significance (VUS) were detected. In five WES negative families, one PKD1 nonsense variation was detected through long-range PCR (LR-PCR)+Oxford nanopore technologies, and one heterozygous deletion in exon 22 of PKD1 gene was detected through multiplex ligation-dependent probe amplification (MLPA). In summary, WES can detect multiple types of variations, which is helpful for early diagnosis and prognosis prediction of renal cyst patients. However, there is still a risk of failing to detect PKD1 gene by WES, therefore, healthcare practitioners should beware of the negative results of WES.
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Variações do Número de Cópias de DNA , Sequenciamento do Exoma , Doenças Renais Císticas , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Estudos Retrospectivos , Adolescente , Criança , Doenças Renais Císticas/genética , Doenças Renais Císticas/diagnóstico , Pré-Escolar , Lactente , Adulto Jovem , Canais de Cátion TRPP/genética , MutaçãoRESUMO
Objective: To evaluate the efficacy and safety of first-line anti-tuberculosis (TB) drugs combined with linezolid in treatment of children with tuberculous meningitis (TBM). Methods: A retrospective cohort study design was performed. Eight-nine Children diagnosed as TBM during January 1st 2016 and December 31st 2023 in Department of Infectious Disease, Children's Hospital of Chongqing Medical University were enrolled in the study. According to different treatment regimens, children were divided into a group of first-line anti-tuberculous drugs (isoniazid, rifampicin, pyrazinamide, ethambutol (HRZE)) and a group of HRZE and linezolid combination (HRZEL). The efficacy and safety of the 2 regimens were compared and the relationship between linezolid drug concentration and adverse reactions were analyzed. Comparisons between groups were performed using χ2 test and Mann-Whitney U test. Results: The 89 children with TBM included 53 males and 36 females with an onset age of 4.6 (1.4, 9.6) years. There were 27 cases in the HZREL group and 62 cases in the HRZE group. Before treatment, positive rate of interferon-gamma release assays (IGRA) in HRZEL group was lower than that in HRZE group (64% (16/25) vs.92% (55/60), χ2=9.82, P<0.05), but protein level of cerebrospinal fluid (CSF) was higher than that in HRZE group (1.2 (1.0, 2.0) vs.0.8 (0.4,1.4) g/L, Z=0.32, P<0.05). By the end of the intensive phase, there were no significant differences of rates of CSF improvement and etiology negativity between HRZEL group and HRZE group (both P>0.05).The 44 TBM children with high CSF protein (>1 g/L) included 25 males and 19 females with an onset age of 6.7 (3.0, 11.8) years. There were 21 cases in the HZREL group and 23 cases in the HRZE group accordingly. Before treatment, there were no significant differences of positive rate of IGRA test and CSF protein level between the 2 groups (62% (13/21) vs. 87% (20/23), 1.7 (1.1, 2.2) vs. 1.5 (1.2, 1.9) g/L, χ2=3.67, Z=0.23, both P>0.05). There were no significant differences in CSF indicators, etiology negativity or imaging remission between the two groups by the end of intensive phase (all P>0.05). Higher frequencies of granulocytopenia, gastrointestinal symptoms as well as withdrawal or change of drugs were found in HRZEL group when compared to those in HRZE group (44% (12/27) vs. 19% (12/62), 7% (2/27) vs. 0, 33% (9/27) vs. 3% (2/62), χ2=6.01, 4.70, 15.74, all P<0.05). Conclusions: The efficacy of HRZEL regimen is similar to conventional HRZE regimen in children with TBM, but with higher adverse effect. Prudentially evaluating the pros and cons of linezolid in the usage of drug-susceptible TB and carefully monitoring of linezolid associated adverse effects is suggested.
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Antituberculosos , Quimioterapia Combinada , Linezolida , Tuberculose Meníngea , Humanos , Tuberculose Meníngea/tratamento farmacológico , Estudos Retrospectivos , Masculino , Feminino , Linezolida/uso terapêutico , Linezolida/administração & dosagem , Antituberculosos/uso terapêutico , Antituberculosos/administração & dosagem , Antituberculosos/efeitos adversos , Criança , Pré-Escolar , Resultado do Tratamento , Lactente , Rifampina/uso terapêutico , Rifampina/administração & dosagem , Etambutol/uso terapêutico , Etambutol/administração & dosagem , Pirazinamida/uso terapêutico , Pirazinamida/administração & dosagem , Isoniazida/uso terapêutico , Isoniazida/administração & dosagem , Isoniazida/efeitos adversosRESUMO
Objective: To evaluate the clinical application effects of a domestic bone-level implant system for restoring single tooth loss, and provide clinical evidence for the promotion and application of domestic implants. Methods: A prospective, multicenter clinical trial was conducted from April 2018 to January 2020 in three institutions: Department of Oral Implantology, School & Hospital of Stomatology, Wuhan University, Department of Stomatology, The First Affiliated Hospital of Zhejiang University School of Medicine, and Department of Stomatology, The Third Hospital of Hebei Medical University. The trial planned to include 100 patients for single tooth implantation and restoration, followed up for 1 year, to evaluate the implantation success rate and other related outcomes. Results: This study screened a total of 142 patients and ultimately included 100, comprising 43 males and 57 females with age of (47.0±12.2) years. Ninety-eight out of 100 patients completed a one-year follow-up (98.0%), while 2 patients terminated the trial early due to implant loosening (2.0%). After a one-year follow-up, the implants of the 98 patients were all functioning successfully, with a success rate of 98.0% (98/100). The patients were satisfied with the overall restoration effect. Conclusions: This study indicates that the domestic bone-level implant system has achieved favorable short-term clinical outcomes for single-tooth implantation and restoration.
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Using data samples collected with the BESIII detector operating at the BEPCII storage ring, the cross section of the inclusive process e^{+}e^{-}âη+X, normalized by the total cross section of e^{+}e^{-}âhadrons, is measured at eight center-of-mass energy points from 2.0000 to 3.6710 GeV. These are the first measurements with momentum dependence in this energy region. Our measurement shows a significant discrepancy compared to the existing fragmentation functions. To address this discrepancy, a new QCD analysis is performed at the next-to-next-to-leading order with hadron mass corrections and higher twist effects, which can explain both the established high-energy data and our measurements reasonably well.
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Using (10.087±0.044)×10^{9} J/ψ events collected with the BESIII detector at the BEPCII storage ring, the processes ΛpâΛp and Λ[over ¯]pâΛ[over ¯]p are studied, where the Λ/Λ[over ¯] baryons are produced in the process J/ψâΛΛ[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(ΛpâΛp)=(12.2±1.6_{stat}±1.1_{syst}) and σ(Λ[over ¯]pâΛ[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 ΛpâΛp, and a strong forward peak for Λ[over ¯]pâΛ[over ¯]p. We present an approach to extract the total elastic cross sections by extrapolation. The study of Λ[over ¯]pâΛ[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.
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AIMS: To explore the independent and additional value of oedema and shrinkage patterns for predicting the disease-free survival (DFS) and neoadjuvant chemotherapy (NAC) response in luminal breast cancer (BC). MATERIALS AND METHODS: Patients with luminal BC who underwent NAC were enrolled in this study from 2017 to 2022. Traditional MRI features include BI-RADS-based MRI descriptors, tumor size, and ADC values, while emerging MRI features include oedema and shrinkage patterns, all of which were evaluated before, early, and after NAC. The changes in features during NAC were also evaluated. The value of features was evaluated through univariate, multivariate analyses. RESULTS: A total of 258 patients were enrolled in this study, of which 77 responded to NAC. Diffuse oedema, stable or increased oedema during early NAC were adverse predictors for treatment response, while a greater reduction in tumor size and increase in ADC value were favorable predictors (all P<0.05). Furthermore, 20 of 60 patients who were followed up experienced recurrence. Diffuse oedema, pre-pectoral or subcutaneous oedema, and non-concentric shrinkage patterns after NAC were risk factors for DFS, whereas a greater increase in ADC value was a protective factor. Incorporating oedema and shrinkage patterns into traditional MRI features improved the predictive performance for treatment response (AUC from 0.76-0.78 to 0.80-0.83) and DFS (C-index from 0.67-69 to 0.75-0.80). CONCLUSIONS: Oedema is an unfavorable predictor for treatment response and survival outcomes, while shrinkage patterns contribute more to the prognostic value, both of which could offer supplementary benefits for clinical outcomes in luminal BC.
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Neoplasias da Mama , Edema , Imageamento por Ressonância Magnética , Terapia Neoadjuvante , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Terapia Neoadjuvante/métodos , Pessoa de Meia-Idade , Edema/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Quimioterapia Adjuvante , Estudos Retrospectivos , Resultado do Tratamento , Valor Preditivo dos Testes , Carga Tumoral , Mama/diagnóstico por imagem , Mama/patologiaRESUMO
Impairments of object recognition are core features of neurodegenerative syndromes, in particular posterior cortical atrophy (PCA; the 'visual-variant Alzheimer's disease'). These impairments arise from damage to higher-level cortical visual regions and are often missed or misattributed to common ophthalmological conditions. Consequently, diagnosis can be delayed for years with considerable implications for patients. We report a new test for the rapid measurement of cortical visual loss - the Graded Incomplete Letters Test (GILT). The GILT is an optimised psychophysical variation of a test used to diagnose cortical visual impairment, which measures thresholds for recognising letters under levels of increasing visual degradation (decreasing "completeness") in a similar fashion to ophthalmic tests. The GILT was administered to UK Biobank participants (total n=2,359) and participants with neurodegenerative conditions characterised by initial cortical visual (PCA, n=18) or memory loss (typical Alzheimer's disease, n=9). UK Biobank participants, including both typical adults and those with ophthalmological conditions, were able to recognise letters under low levels of completeness. In contrast, participants with PCA consistently made errors with only modest decreases in completeness. GILT sensitivity to PCA was 83.3% for participants reaching the 80% accuracy cut-off, increasing to 88.9% using alternative cut-offs (60% or 100% accuracy). Specificity values were consistently over 94% when compared to UK Biobank participants without or with documented visual conditions, regardless of accuracy cut-off. These first-release UK Biobank and clinical verification data suggest the GILT has utility in both rapidly detecting visual perceptual losses following posterior cortical damage and differentiating perceptual losses from common eye-related conditions.
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We present measurements of the Born cross sections for the processes e^{+}e^{-}âωχ_{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^{-}âωχ_{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^{-}âωχ_{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.
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Based on (10087±44)×10^{6} J/ψ events collected with the BESIII detector, a partial wave analysis of the decay J/ψâγK_{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/ψâγX(2370)]×B[X(2370)âf_{0}(980)η^{'}]×B[f_{0}(980)âK_{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.
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We report the measurement of the inclusive cross sections for e^{+}e^{-}ânOCH (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)ânOCH]=(25.2±16.1±30.4)%[(6.4±4.8±7.7)%] and B[R(3780)ânOCH]=(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.
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Objective: To retrospectively analyze the treatment status of tyrosine kinase inhibitors (TKI) in newly diagnosed patients with chronic myeloid leukemia (CML) in China. Methods: Data of chronic phase (CP) and accelerated phase (AP) CML patients diagnosed from January 2006 to December 2022 from 77 centers, ≥18 years old, and receiving initial imatinib, nilotinib, dasatinib or flumatinib-therapy within 6 months after diagnosis in China with complete data were retrospectively interrogated. The choice of initial TKI, current TKI medications, treatment switch and reasons, treatment responses and outcomes as well as the variables associated with them were analyzed. Results: 6 893 patients in CP (n=6 453, 93.6%) or AP (n=440, 6.4%) receiving initial imatinib (n=4 906, 71.2%), nilotinib (n=1 157, 16.8%), dasatinib (n=298, 4.3%) or flumatinib (n=532, 7.2%) -therapy. With the median follow-up of 43 (IQR 22-75) months, 1 581 (22.9%) patients switched TKI due to resistance (n=1 055, 15.3%), intolerance (n=248, 3.6%), pursuit of better efficacy (n=168, 2.4%), economic or other reasons (n=110, 1.6%). The frequency of switching TKI in AP patients was significantly-higher than that in CP patients (44.1% vs 21.5%, P<0.001), and more AP patients switched TKI due to resistance than CP patients (75.3% vs 66.1%, P=0.011). Multi-variable analyses showed that male, lower HGB concentration and ELTS intermediate/high-risk cohort were associated with lower cytogenetic and molecular responses rate and poor outcomes in CP patients; higher WBC count and initial the second-generation TKI treatment, the higher response rates; Ph(+) ACA at diagnosis, poor PFS. However, Sokal intermediate/high-risk cohort was only significantly-associated with lower CCyR and MMR rates and the poor PFS. Lower HGB concentration and larger spleen size were significantly-associated with the lower cytogenetic and molecular response rates in AP patients; initial the second-generation TKI treatment, the higher treatment response rates; lower PLT count, higher blasts and Ph(+) ACA, poorer TFS; Ph(+) ACA, poorer OS. Conclusion: At present, the vast majority of newly-diagnosed CML-CP or AP patients could benefit from TKI treatment in the long term with the good treatment responses and survival outcomes.
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Dasatinibe , Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , China , Dasatinibe/uso terapêutico , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Pirimidinas/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , /uso terapêuticoRESUMO
We perform a study of the χ_{c1}(3872) line shape using the data samples of e^{+}e^{-}âγχ_{c1}(3872), χ_{c1}(3872)âD^{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.
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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/ψâγ3(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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We present cross sections for the reaction e^{+}e^{-}âK_{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
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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.
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We perform for the first time an amplitude analysis of the decay D^{+}âK_{S}^{0}π^{+}η and report the observation of the decay D^{+}âK_{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^{+}âK_{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^{+}âK_{S}^{0}π^{+}η is measured to be (1.27±0.04_{stat}±0.03_{syst})%. The branching fractions of intermediate processes D^{+}âK_{S}^{0}a_{0}(980)^{+} with a_{0}(980)^{+}âπ^{+}η and D^{+}âπ^{+}K[over ¯]_{0}^{*}(1430)^{0} with K[over ¯]_{0}^{*}(1430)^{0}âK_{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.
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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}^{+}âπ^{+}π^{-}e^{+}ν_{e}, where the D_{s}^{+} is produced via the process e^{+}e^{-}âD_{s}^{*±}D_{s}^{∓}. We observe the f_{0}(980) in the π^{+}π^{-} system and the branching fraction of the decay D_{s}^{+}âf_{0}(980)e^{+}ν_{e} with f_{0}(980)âπ^{+}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}^{+}âf_{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 câs 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}^{+}âf_{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}^{+}âf_{0}(500)e^{+}ν_{e}, f_{0}(500)âπ^{+}π^{-} decay is set to be 3.3×10^{-4} at 90% confidence level.