Evidence for Modification of b Quark Hadronization in High-Multiplicity pp Collisions at sqrt[s]=13 TeV

The production rate of B_{s}^{0} mesons relative to B^{0} mesons is measured by the LHCb experiment in pp collisions at a center-of-mass energy sqrt[s]=13  TeV over the forward rapidity interval 2 Collapse

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First Observation of a Doubly Charged Tetraquark and Its Neutral Partner

A combined amplitude analysis is performed for the decays B^{0}→D[over ¯]^{0}D_{s}^{+}π^{-} and B^{+}→D^{-}D_{s}^{+}π^{+}, which are related by isospin symmetry. The analysis is based on data collected by the LHCb detector in proton-proton collisions at center-of-mass energies of 7, 8, and 13 TeV. The full data sample corresponds to an integrated luminosity of 9  fb^{-1}. Two new resonant states with masses of 2.908±0.011±0.020  GeV and widths of 0.136±0.023±0.013  GeV are observed, which decay to D_{s}^{+}π^{+} and D_{s}^{+}π^{-} respectively. The former state indicates the first observation of a doubly charged open-charm tetraquark state with minimal quark content [cs[over ¯]ud[over ¯]], and the latter state is a neutral tetraquark composed of [cs[over ¯]u[over ¯]d] quarks. Both states are found to have spin-parity of 0^{+}, and their resonant parameters are consistent with each other, which suggests that they belong to an isospin triplet.

Search for Rare Decays of D^{0} Mesons into Two Muons

A search for the very rare D^{0}→μ^{+}μ^{-} decay is performed using data collected by the LHCb experiment in proton-proton collisions at sqrt[s]=7, 8, and 13 TeV, corresponding to an integrated luminosity of 9  fb^{-1}. The search is optimized for D^{0} mesons from D^{*+}→D^{0}π^{+} decays but is also sensitive to D^{0} mesons from other sources. No evidence for an excess of events over the expected background is observed. An upper limit on the branching fraction of this decay is set at B(D^{0}→μ^{+}μ^{-})<3.1×10^{-9} at a 90% C.L. This represents the world's most stringent limit, constraining models of physics beyond the standard model.

Nuclear Modification Factor of Neutral Pions in the Forward and Backward Regions in p-Pb Collisions

The nuclear modification factor of neutral pions is measured in proton-lead collisions collected at a center-of-mass energy per nucleon of 8.16 TeV with the LHCb detector. The π^{0} production cross section is measured differentially in transverse momentum (p_{T}) for 1.5 Collapse

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Observation of a J/ψΛ Resonance Consistent with a Strange Pentaquark Candidate in B^{-}→J/ψΛp[over ¯] Decays

An amplitude analysis of B^{-}→J/ψΛp[over ¯] decays is performed using 4400 signal candidates selected on a data sample of pp collisions recorded at center-of-mass energies of 7, 8, and 13 TeV with the LHCb detector, corresponding to an integrated luminosity of 9  fb^{-1}. A narrow resonance in the J/ψΛ system, consistent with a pentaquark candidate with strangeness, is observed with high significance. The mass and the width of this new state are measured to be 4338.2±0.7±0.4  MeV and 7.0±1.2±1.3  MeV, where the first uncertainty is statistical and the second systematic. The spin is determined to be 1/2 and negative parity is preferred. Because of the small Q-value of the reaction, the most precise single measurement of the B^{-} mass to date, 5279.44±0.05±0.07  MeV, is obtained.

First Study of Reaction Ξ^{0}n→Ξ^{-}p Using Ξ^{0}-Nucleus Scattering at an Electron-Positron Collider

Using (1.0087±0.0044)×10^{10}  J/ψ events collected with the BESIII detector at the BEPCII storage ring, the process Ξ^{0}n→Ξ^{-}p is studied, where the Ξ^{0} baryon is produced in the process J/ψ→Ξ^{0}Ξ[over ¯]^{0} and the neutron is a component of the ^{9}Be, ^{12}C, and ^{197}Au nuclei in the beam pipe. A clear signal is observed with a statistical significance of 7.1σ. The cross section of the reaction Ξ^{0}+^{9}Be→Ξ^{-}+p+^{8}Be is determined to be σ(Ξ^{0}+^{9}Be→Ξ^{-}+p+^{8}Be)=(22.1±5.3_{stat}±4.5_{sys})  mb at the Ξ^{0} momentum of 0.818  GeV/c, where the first uncertainty is statistical and the second is systematic. No significant H-dibaryon signal is observed in the Ξ^{-}p final state. This is the first study of hyperon-nucleon interactions in electron-positron collisions and opens up a new direction for such research.

Measurements of Normalized Differential Cross Sections of Inclusive π^{0} and K_{S}^{0} Production in e^{+}e^{-} Annihilation at Energies from 2.2324 to 3.6710 GeV

Based on electron positron collision data collected with the BESIII detector operating at the BEPCII storage rings, the differential cross sections of inclusive π^{0} and K_{S}^{0} production as a function of hadron momentum, normalized by the total cross section of the e^{+}e^{-}→hadrons process, are measured at six center-of-mass energies from 2.2324 to 3.6710 GeV. Our results, which cover a relative hadron energy range from 0.1 to 0.9, significantly deviate from several theoretical calculations based on existing fragmentation functions.

Precision Measurement of the Decay Σ^{+}→pγ in the Process J/ψ→Σ^{+}Σ[over ¯]^{-}

Using (10 087±44)×10^{6} J/ψ events collected with the BESIII detector, the radiative hyperon decay Σ^{+}→pγ is studied at an electron-positron collider experiment for the first time. The absolute branching fraction is measured to be (0.996±0.021_{stat}±0.018_{syst})×10^{-3}, which is lower than its world average value by 4.2 standard deviations. Its decay asymmetry parameter is determined to be -0.652±0.056_{stat}±0.020_{syst}. The branching fraction and decay asymmetry parameter are the most precise to date, and the accuracies are improved by 78% and 34%, respectively.

[A prospective randomized controlled study of antibiotic bone cement in the treatment of diabetic foot ulcer]

Objective: To investigate the clinical effects and related mechanism of antibiotic bone cement in treating diabetic foot ulcer (DFU). Methods: A prospective randomized controlled study was conducted. From August 2020 to August 2022, 24 patients with DFU who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University. According to the block randomization, the patients were divided into 2 groups, with 12 patients in each group. In antibiotic bone cement group, there were 7 male and 5 female patients, aged (64±8) years, with the ulcer area of (41±21) cm2. In silver sulfadiazine group, there were 8 male and 4 female patients, aged (62±8) years, with the ulcer area of (38±19) cm2. Under the condition of ensuring the patency of at least one main inferior genicular artery in each patient, the continuous vacuum sealing drainage was performed for 3-5 days after thorough debridement. Thereafter, the wounds in antibiotic bone cement group were treated with gentamicin-laden bone cement, and the wounds in silver sulfadiazine group were treated with silver sulfadiazine cream for dressing change. After 3 weeks of dressing change, the wound was covered with split-thickness skin graft from the lateral thigh on the affected side. Before debridement and after 3 weeks of dressing change, the blood flow intensities of wound tissue and normal skin tissue in foot were measured using laser Doppler flowmeter, and then, the percentage of relative blood flow intensity of wound and the change rate of blood flow intensity were calculated. After 3 weeks of dressing change, the wound margin tissue was taken, the number of CD31-positive neovascular and the vascular morphology were observed and detected by immunohistochemical staining, the morphology of blood vessels surrounded by CD31 and α-smooth muscle actin (α-SMA) double-positive cells was observed by immunofluorescence staining, the cell proliferation activity was evaluated by immunofluorescence staining (denoted as the ratio of Ki67 positive cells), and the protein expression of vascular endothelial growth factor receptor 2 (VEGFR2) was detected by Western blotting. The skin graft survival was observed 3-5 days after skin grafting, and the wound healing time was recorded. Data were statistically analyzed with independent sample t test and Fisher's exact probability test. Results: The percentages of relative blood flow intensity of wounds of patients before debridement were similar between the two groups (P>0.05). After 3 weeks of dressing change, the percentage of relative blood flow intensity of wounds and the change rate of blood flow intensity of patients in antibiotic bone cement group were (44.7±2.0)% and (129±12)%, respectively, which were significantly higher than (28.3±1.2)% and (41±8)% in silver sulfadiazine group (with t values of 24.15 and 20.97, respectively, P<0.05). After 3 weeks of dressing change, compared with those in silver sulfadiazine group, the number of CD31-positive neovascular in the wound margin tissue of patients in antibiotic bone cement group was significantly increased (t=33.81, P<0.05) with larger diameter and more regular arrangement, the vascular wall continuity surrounded by CD31 and α-SMA double-positive cells was better, and the ratio of Ki67 positive cells and protein expression of VEGFR2 were significantly increased (with t values of 40.97 and 47.38, respectively, P<0.05). On post skin grafting day 3-5, all the patients in antibiotic bone cement group and 8 patients in silver sulfadiazine group had good skin graft survival, while 4 patients in silver sulfadiazine group showed spotted/patchy skin graft necrosis, which were cured after corresponding treatment. The wound healing time of patients in antibiotic bone cement group was (47.1±2.9) d, which was significantly shorter than (58.8±2.3) d in silver sulfadiazine group (t=10.86, P<0.05). Conclusions: Compared with silver sulfadiazine, clinical application of antibiotic bone cement for treating DFU has the characteristics of accelerating wound healing and better reconstruction of local blood flow, which may be closely related to the fact that antibiotic bone cement promoted the local angiogenesis effectively in the wound through enhancing the expression of VEGFR2.

Measurements of the Electric and Magnetic Form Factors of the Neutron for Timelike Momentum Transfer

We present the first measurements of the electric and magnetic form factors of the neutron in the timelike (positive q^{2}) region as function of four-momentum transfer. We explored the differential cross sections of the reaction e^{+}e^{-}→n[over ¯]n with data collected with the BESIII detector at the BEPCII accelerator, corresponding to an integrated luminosity of 354.6  pb^{-1} in total at twelve center-of-mass energies between sqrt[s]=2.0-2.95  GeV. A relative uncertainty of 18% and 12% for the electric and magnetic form factors, respectively, is achieved at sqrt[s]=2.3935  GeV. Our results are comparable in accuracy to those from electron scattering in the comparable spacelike region of four-momentum transfer. The electromagnetic form factor ratio R_{em}≡|G_{E}|/|G_{M}| is within the uncertainties close to unity. We compare our result on |G_{E}| and |G_{M}| to recent model predictions, and the measurements in the spacelike region to test the analyticity of electromagnetic form factors.

Observation of a New X(3872) Production Process e^{+}e^{-}→ωX(3872)

Using 4.7  fb^{-1} of e^{+}e^{-} collision data at center-of-mass energies from 4.661 to 4.951 GeV collected by the BESIII detector at the BEPCII collider, we observe the X(3872) production process e^{+}e^{-}→ωX(3872) for the first time. The significance is 7.8σ, including both the statistical and systematic uncertainties. The e^{+}e^{-}→ωX(3872) Born cross section and the corresponding upper limit at 90% confidence level at each energy point are reported. The line shape of the cross section indicates that the ωX(3872) signals may be from the decays of some nontrivial structures.

Observation of Three Charmoniumlike States with J^{PC}=1^{--} in e^{+}e^{-}→D^{*0}D^{*-}π^{+}

The Born cross sections of the process e^{+}e^{-}→D^{*0}D^{*-}π^{+} at center-of-mass energies from 4.189 to 4.951 GeV are measured for the first time. The data samples used correspond to an integrated luminosity of 17.9  fb^{-1} and were collected by the BESIII detector operating at the BEPCII storage ring. Three enhancements around 4.20, 4.47, and 4.67 GeV are visible. The resonances have masses of 4209.6±4.7±5.9  MeV/c^{2}, 4469.1±26.2±3.6  MeV/c^{2}, and 4675.3±29.5±3.5  MeV/c^{2} and widths of 81.6±17.8±9.0  MeV, 246.3±36.7±9.4  MeV, and 218.3±72.9±9.3  MeV, respectively, where the first uncertainties are statistical and the second systematic. The first and third resonances are consistent with the ψ(4230) and ψ(4660) states, respectively, while the second one is compatible with the ψ(4500) observed in the e^{+}e^{-}→K^{+}K^{-}J/ψ process. These three charmoniumlike ψ states are observed in the e^{+}e^{-}→D^{*0}D^{*-}π^{+} process for the first time.

Evidence for the Cusp Effect in η' Decays into ηπ^{0}π^{0}

Using a sample of 4.3×10^{5} η^{'}→ηπ^{0}π^{0} events selected from the ten billion J/ψ event dataset collected with the BESIII detector, we study the decay η^{'}→ηπ^{0}π^{0} within the framework of nonrelativistic effective field theory. Evidence for a structure at π^{+}π^{-} mass threshold is observed in the invariant mass spectrum of π^{0}π^{0} with a statistical significance of around 3.5σ, which is consistent with the cusp effect as predicted by the nonrelativistic effective field theory. After introducing the amplitude for describing the cusp effect, the ππ scattering length combination a_{0}-a_{2} is determined to be 0.226±0.060_{stat}±0.013_{syst}, which is in good agreement with theoretical calculation of 0.2644±0.0051.

[Analysis of the characteristics of delayed high-degree atrioventricular block after transcatheter aortic valve replacement]

Objective: To investigate the characteristics of delayed high-degree atrioventricular block (DHAVB) after transcatheter aortic valve replacement (TAVR). Methods: One hundred and seventy-six patients who underwent TAVR with a self-extending valve between May 2014 and November 2018 in the Department of Cardiology, West China Hospital of Sichuan University, were retrospectively enrolled, including 101 males and 75 females, aged 54-92 (73±7) years, and the data were collected during the perioperative and 30 d follow-up periods. According to the occurrence of HAVB after TAVR, 160 patients were divided into no-HAVB group (145 cases) and DHAVB group (15 cases), except 16 patients who developed HAVB within 2 days after TAVR. Baseline data, intraoperative data, and immediate postoperative ECG characteristics were compared between the two groups, and logistic regression models were used to analyze the factors associated with the occurrence of DHAVB after TAVR. Meanwhile, the diagnostic ability of the postoperative routine 12-lead ECG for DHAVB was evaluated using the ambulatory ECG findings as the standard diagnosis. Results: The incidence of DHAVB was 8.5% (15/176) and occurred at 5 (4, 6) d. Compared with the no-HAVB group. The percentage of no new conduction block on the immediate postoperative ECG was lower in the DHAVB group [6/15 vs 66.2%(96/145), P=0.044], and the percentage of new right bundle branch block on the immediate postoperative ECG was higher [4/15 vs 3.4%(5/145), P=0.002]. Multifactorial logistic regression analysis showed that right bundle branch block on the immediate postoperative ECG [OR (95%CI):6.60 (1.26-34.47), P=0.025] was an associated factor for the development of DHAVB after TAVR. The specificity of postoperative routine 12-lead ECG for the diagnosis of DHAVB was 100% (145/145), but the sensitivity was only 73.3% (11/15). Conclusions: The incidence of DHAVB after TAVR is also high in Chinese. The immediate postoperative ECG characteristics of patients who underwent TAVR are associated with DHAVB events, and applying these characteristics to risk stratify patients may optimize the management of DHAVB after TAVR.

Study of the Semileptonic Decay Λ_{c}^{+}→Λe^{+}ν_{e}

The study of the Cabibbo-favored semileptonic decay Λ_{c}^{+}→Λe^{+}ν_{e} is reported using a 4.5  fb^{-1} data sample of e^{+}e^{-} annihilations collected at center-of-mass energies ranging from 4.600 GeV to 4.699 GeV with the BESIII detector at the BEPCII collider. The branching fraction of the decay is measured to be B(Λ_{c}^{+}→Λe^{+}ν_{e})=(3.56±0.11_{stat}±0.07_{syst})%, which is the most precise measurement to date. Furthermore, we perform an investigation of the internal dynamics in Λ_{c}^{+}→Λe^{+}ν_{e}. We provide the first direct comparisons of the differential decay rate and form factors with those predicted from lattice quantum chromodynamics (LQCD) calculations. Combining the measured branching fraction with a q^{2}-integrated rate predicted by LQCD, we determine |V_{cs}|=0.936±0.017_{B}±0.024_{LQCD}±0.007_{τ_{Λ_{c}}}.

[Effects of exosomes from hepatocyte growth factor-modified human adipose mesenchymal stem cells on full-thickness skin defect in diabetic mice]

Objective: To investigate the effects and mechanism of exosomes from hepatocyte growth factor (HGF)-modified human adipose mesenchymal stem cells (ADSCs) on full-thickness skin defect wounds in diabetic mice. Methods: The experimental study method was adopted. Discarded adipose tissue of 3 healthy females (10-25 years old) who underwent abdominal surgery in the Department of Plastic Surgery of First Affiliated Hospital of Air Force Medical University from February to May 2021 was collected, and primary ADSCs were obtained by collagenase digestion method and cultured for 7 days. Cell morphology was observed by inverted phase contrast microscope. The ADSCs of third passage were transfected with HGF lentivirus and cultured for 5 days, and then the fluorescence of cells was observed by imaging system and the transfection rate was calculated. The exosomes of ADSCs of the third to sixth passages and the HGF transfected ADSCs of the third to sixth passages were extracted by density gradient centrifugation, respectively, and named, ADSC exosomes and HGF-ADSC exosomes. The microscopic morphology of exosomes was observed by transmission electron microscopy, and the positive expressions of CD9, CD63, and CD81 of exosomes were detected by flow cytometry, respectively. Twenty-four 6-week-old male Kunming mice were selected to make the diabetic models, and full-thickness skin defect wounds were made on the backs of mice. According to the random number table method, the mice were divided into phosphate buffer solution (PBS) group, HGF alone group, ADSC exosome alone group, and HGF-ADSC exosome group, with 6 mice in each group, and treated accordingly. On post injury day (PID) 3, 7, 10, and 14, the wounds were observed and the wound healing rate was calculated; the blood flow intensity of wound base was detected by Doppler flowmeter and the ratio of relative blood flow intensity on PID 10 was calculated. On PID 10, the number of Ki67 positive cells in wounds was detected by immunofluorescence method, and the number of new-vascularity of CD31 positive staining and tubular neovascularization in the wounds was detected by immunohistochemistry method; the protein expressions of protein endothelial nitric oxide synthase (eNOS), phosphatidylinositol 3-kinase (PI3K), phosphorylated PI3K (p-PI3K), protein kinase B (Akt) and phosphorylated Akt (p-Akt) in wounds were detected by Western blotting, and the ratios of p-PI3K to PI3K and p-Akt to Akt were calculated. On PID 14, the defect length and collagen regeneration of wound skin tissue were detected by hematoxylin and eosin staining and Masson staining, respectively, and the collagen volume fraction (CVF) was calculated. The number of samples is 3 in all cases. Data were statistically analyzed with repeated measurement analysis of variance, one-way analysis of variance, and Tukey test. Results: After 7 days of culture, the primary ADSCs were spindle shaped and arranged in vortex shape after dense growth. After 5 days of culture, HGF transfected ADSCs of the third passage carried green fluorescence, and the transfection rate was 85%. The ADSC exosomes and HGF-ADSC exosomes were similar in microscopic morphology, showing vesicular structures with an average particle size of 103 nm and 98 nm respectively, and both were CD9, CD63, and CD81 positive. On PID 3, the wounds of mice in the 4 groups were all red and swollen, with a small amount of exudate. On PID 7, the wounds of HGF-ADSC exosome group were gradually reduced, while the wounds of the other three groups were not significantly reduced. On PID 10, the wounds in the 4 groups were all reduced and scabbed. On PID 14, the wounds in HGF-ADSC exosome group were basically healed, while the residual wounds were found in the other three groups. On PID 3, the healing rates of wounds in the four groups were similar (P>0.05); On PID 7 and 10, the wound healing rates in HGF-ADSC exosome group were significantly higher than those in PBS group, HGF alone group, and ADSC exosome alone group, respectively (with q values of 13.11, 13.11, 11.89, 12.85, 11.28, and 7.74, respectively, all P<0.01); on PID 14, the wound healing rate in HGF-ADSC exosome group was significantly higher than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 15.50, 11.64, and 6.36, respectively, all P<0.01). On PID 3, there was no obvious blood supply in wound base of mice in the 4 groups. On PID 7, microvessels began to form in the wound base of HGF-ADSC exosome group, while the wound base of the other three groups was only congested at the wound edge. On PID 10, microvessel formation in wound base was observed in the other 3 groups except in PBS group, which had no obvious blood supply. On PID 14, the blood flow intensity of wound base in HGF-ADSC exosome group was stronger than that in the other 3 groups, and the distribution was uniform. On PID 10, the ratio of wound base relative blood flow intensity in HGF-ADSC exosome group was significantly higher than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 23.73, 19.32, and 9.48, respectively, all P<0.01); The numbers of Ki67-positive cells and new-vascularity of wounds in HGF-ADSC exosome group were significantly higher than those in PBS group, HGF alone group, and ADSC exosome alone group, respectively (with q values of 19.58, 18.20, 11.04, 20.68, 13.79, and 8.12, respectively, P<0.01). On PID 10, the protein expression level of eNOS of wounds in HGF-ADSC exosome group was higher than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 53.23, 42.54, and 26.54, respectively, all P<0.01); the ratio of p-PI3K to PI3K and the ratio of p-Akt to Akt of wounds in HGF-ADSC exosome group were significantly higher than those in PBS group, HGF alone group, and ADSC exosome alone group, respectively (with q values of 16.11, 11.78, 6.08, 65.54, 31.63, and 37.86, respectively, P<0.01). On PID 14, the length of skin tissue defect in the wounds of HGF-ADSC exosome group was shorter than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 20.51, 18.50, and 11.99, respectively, all P<0.01); the CVF of wounds in HGF-ADSC exosome group was significantly higher than that in PBS group, HGF alone group and ADSC exosome alone group (with q values of 31.31, 28.52, and 12.35, respectively, all P<0.01). Conclusions: Human HGF-ADSC exosomes can significantly promote wound healing in diabetic mice by increasing neovascularization in wound tissue, and the mechanism may be related to the increased expression of eNOS in wounds by activating PI3K/Akt signaling pathway.

Measurement of the Absolute Branching Fraction and Decay Asymmetry of Λ→nγ

The radiative hyperon decay Λ→nγ is studied using (10087±44)×10^{6}  J/ψ events collected with the BESIII detector operating at BEPCII. The absolute branching fraction of the decay Λ→nγ is determined to be (0.832±0.038_{stat}±0.054_{syst})×10^{-3}, which is a factor of 2.1 lower and 5.6 standard deviations different than the previous measurement. By analyzing the joint angular distribution of the decay products, the first determination of the decay asymmetry α_{γ} is reported with a value of -0.16±0.10_{stat}±0.05_{syst}.

[Characteristics and risk factors of spinal epidural hematoma after unilateral biportal endoscopic lumbar interbody fusion]

Objective: To investigate the incidence, characteristics and risk factors of spinal epidural hematoma after unilateral biportal endoscopic (UBE) lumbar spine surgery. Methods: The clinical data of 105 patients who underwent lumbar spine surgery under UBE in Guangdong Provincial People's Hospital from February 2020 to March 2021 were retrospectively reviewed. Of the patients, 48(45.7%) were male and 57(54.3%) were female, the mean age was (60.1±11.4) years (ranged 26 to 85 years). The MRI images at the third day post-surgery were observed, and the occurrence of hematoma was counted. Patients were assigned to normal group and hematoma group based on the presence of hematoma or not. The related clinical indicators of each patients were collected and used for comparison between two different groups. Logistic stepwise regression model was used to analyze whether each index was a risk factor for hematoma after the UBE lumbar fusion. Results: The total hematoma incidence rate was 28.6%(30/105), the symptomatic hematoma rate was 6.7%(7/105), and the hematoma reoperation rate was 0.9%(1/105). Univariate logistic regression analysis showed that hypertension (OR=3.368, 95%CI: 1.389-8.171), diabetes (OR=3.589, 95%CI: 1.230-10.476), admission systolic blood pressure>140 mmHg (1 mmHg=0.133 kPa,OR=3.687, 95%CI: 1.493-9.017), platelets<200×10⁹/L (OR=0.300, 95%CI: 0.119-0.785), preoperative blood calcium<2.25 mmol/L (OR=0.340, 95%CI: 0.142-0.818), spinal stenosis grade D (OR=4.462, 95%CI: 1.810-10.996) were possible risk factors for spinal hematoma after UBE lumbar fusion. Multivariate logistic regression analysis showed that admission blood pressure systolic blood pressure>140 mmHg (OR=3.788, 95%CI:1.055-13.606), preoperative blood calcium<2.25 mmol/L (OR=78.544, 95%CI:3.895-1 584.058) and spinal stenosis grade D (OR=3.698, 95%CI:1.110-12.325) were risk factors for spinal hematoma after UBE lumbar fusion (all P<0.05). Conclusion: The types of spinal canal hematoma after UBE lumbar fusion include localized and extended type. The risk factors for hematoma include high systolic blood pressure on admission, low preoperative blood calcium and severe spinal stenosis.

Observation of an a_{0}-like State with Mass of 1.817 GeV in the Study of D_{s}^{+}→K_{S}^{0}K^{+}π^{0} Decays

Using e^{+}e^{-} annihilation data corresponding to an integrated luminosity of 6.32  fb^{-1} collected at center-of-mass energies between 4.178 and 4.226 GeV with the BESIII detector, we perform the first amplitude analysis of the decay D_{s}^{+}→K_{S}^{0}K^{+}π^{0} and determine the relative branching fractions and phases for intermediate processes. We observe an a_{0}-like state with mass of 1.817 GeV in its decay to K_{S}^{0}K^{+} for the first time. In addition, we measure the ratio {B[D_{s}^{+}→K[over ¯]^{*}(892)^{0}K^{+}]/B[D_{s}^{+}→K[over ¯]^{0}K^{*}(892)^{+}]} to be 2.35_{-0.23stat}^{+0.42}±0.10_{syst}. Finally, we provide a precision measurement of the absolute branching fraction B(D_{s}^{+}→K_{S}^{0}K^{+}π^{0})=(1.46±0.06_{stat}±0.05_{syst})%.

[Effect of autologous hematopoietic stem cell transplantation on minimal residual disease in patients with multiple myeloma]

Objective: To evaluate the effect of autologous hematopoietic stem cell transplantation (ASCT) on minimal residual disease (MRD) in patients with multiple myeloma (MM). Method: From August 2018 to August 2021, 92 patients newly diagnosed with MM who had received either the bortezomib combined with cyclophosphamide and dexamethasone (VCD) or the bortezomib, lenalidomide and dexamethasone (VRD) induction regimens followed by sequential ASCT were assessed for overall survival (OS) and the MRD negative rate. The differences in efficacy at 100 days after transplantation were assessed according to factors, including age, risk stratification, target organ damage, and pre-transplant regimen, etc. Results: Among the 92 patients, there were 45 males and 47 females, with a median age of 57.3 (35-67) years. Fifty-seven patients received the VCD regimen, and 35 received VRD as induction regimen. Forty-three patients received busulphan combined with cyclophosphamide and etoposide (BCV), and 49 patients received high-dose melphan (HDM) regimen as pre-transplantation treatment. After transplantation, the total complete remission (CR) rate of 92 patients increased from 23.9% (22/92) to 58.7% (54/92), and the MRD negative rate increased from 4.4% (4/92) to 33.7% (31/92), and the differences were statistically significant (all P<0.05). After transplantation, the MRD negative rates of patients with PR, VGPR and ≥CR before transplantation were 17.6% (6/34), 33.3% (12/36) and 59.1% (13/22), respectively (P=0.006). The CR rates of patients with or without plasmacytoma at initial diagnosis were 36.4% (4/11) and 65.4% (53/81), respectively (P=0.029), and the MRD negative rates were 18.2% (2/11) and 39.5% (32/81), respectively (P=0.037), and the differences were statistically significant. The MRD negative rates in high-risk patients and standard-risk group were 30.5% (12/28) and 42.9% (18/59), respectively (P=0.258). For patients who achieved efficacy above VGPR before transplantation, the MRD negative rates after transplantation in VCD-induced group and VRD group were 29% (9/31) and 59.3% (16/27), respectively (P=0.033), and in BCV group and HDM group were 24% (6/25) and 57.6% (19/33), respectively (P=0.016), the differences between the groups were both statistically significant. Conclusion: ASCT can overcome the adverse factors such as high-risk cytogenetic abnormalities, and significantly improve the CR rate and MRD negative rate of MM patients. However, the benefit for patients with plasmacytoma at initial diagnosis is not as good as that of patients without.

Precise Measurements of Decay Parameters and CP Asymmetry with Entangled Λ-Λ[over ¯] Pairs

Based on 10 billion J/ψ events collected at the BESIII experiment, a search for CP violation in Λ decay is performed in the difference between CP-odd decay parameters α_{-} for Λ→pπ^{-} and α_{+} for Λ[over ¯]→p[over ¯]π^{+} by using the process e^{+}e^{-}→J/ψ→ΛΛ[over ¯]. With a five-dimensional fit to the full angular distributions of the daughter baryon, the most precise values for the decay parameters are determined to be α_{-}=0.7519±0.0036±0.0024 and α_{+}=-0.7559±0.0036±0.0030, respectively. The Λ and Λ[over ¯] averaged value of the decay parameter is extracted to be α_{avg}=0.7542±0.0010±0.0024 with unprecedented accuracy. The CP asymmetry A_{CP}=(α_{-}+α_{+})/(α_{-}-α_{+}) is determined to be -0.0025±0.0046±0.0012, which is one of the most precise measurements in the baryon sector. The reported results for the decay parameter will play an important role in the studies of the polarizations and CP violations for the strange, charmed and beauty baryons.

Evidence for a Neutral Near-Threshold Structure in the K_{S}^{0} Recoil-Mass Spectra in e^{+}e^{-}→K_{S}^{0}D_{s}^{+}D^{*-} and e^{+}e^{-}→K_{S}^{0}D_{s}^{*+}D^{-}

We study the processes e^{+}e^{-}→K_{S}^{0}D_{s}^{+}D^{*-} and e^{+}e^{-}→K_{S}^{0}D_{s}^{*+}D^{-}, as well as their charge conjugated processes, at five center-of-mass energies between 4.628 and 4.699 GeV, using data samples corresponding to an integrated luminosity of 3.8  fb^{-1} collected by the BESIII detector at the BEPCII storage ring. Based on a partial reconstruction technique, we find evidence of a structure near the thresholds for D_{s}^{+}D^{*-} and D_{s}^{*+}D^{-} production in the K_{S}^{0} recoil-mass spectrum, which we refer to as the Z_{cs}(3985)^{0}. Fitting with a Breit-Wigner line shape, we find the mass of the structure to be (3992.2±1.7±1.6)  MeV/c^{2} and the width to be (7.7_{-3.8}^{+4.1}±4.3)  MeV, where the first uncertainties are statistical and the second are systematic. The significance of the Z_{cs}(3985)^{0} signal is found to be 4.6σ including both the statistical and systematic uncertainty. We report the Born cross section multiplied by the branching fraction at different energy points. The mass of the Z_{cs}(3985)^{0} is close to that of the Z_{cs}(3985)^{+}. Assuming SU(3) symmetry, the cross section of the neutral channel is consistent with that of the charged one. Hence, we conclude that the Z_{cs}(3985)^{0} is the isospin partner of the Z_{cs}(3985)^{+}.

First Measurement of the Z→μ^{+}μ^{-} Angular Coefficients in the Forward Region of pp Collisions at sqrt[s]=13 TeV

The first study of the angular distribution of μ^{+}μ^{-} pairs produced in the forward rapidity region via the Drell-Yan reaction pp→γ^{*}/Z+X→ℓ^{+}ℓ^{-}+X is presented, using data collected with the LHCb detector at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.1  fb^{-1}. The coefficients of the five leading terms in the angular distribution are determined as a function of the dimuon transverse momentum and rapidity. The results are compared to various theoretical predictions of the Z-boson production mechanism and can also be used to probe transverse-momentum-dependent parton distributions within the proton.

Ectopic expression of BrIQD35 promotes drought stress tolerance in Nicotiana benthamiana

The plant IQD gene family is responsive to a variety of stresses. In this study, we studied the structural features and functions of the gene BrIQD35 in Chinese cabbage, a member of the IQD gene family. BrIQD35 was cloned and shown to contain an IQ motif. Transient expression of BrIQD35 indicated that it was localized on the plasma membrane and was significantly upregulated under drought and salt stress in Chinese cabbage. To further identify the function of BrIQD35, it was heterologously overexpressed in Nicotiana benthamiana. Although there was no significant difference between BrIQD35-overexpressed and wild-type (WT) plants under salt stress, WT N. benthamiana showed more wilting than the BrIQD35-overexpressed plants under drought stress. Since the IQ motif has been annotated as a CaM binding site, yeast two-hybrid assays were used to explore the interaction between BrIQD35 and CaM. The results indicated that BrIQD35 interacts weakly with CaMb, but not with CaMa, suggesting that BrIQD35 may function through the Ca2+ -CaMb pathway. The findings reveal a novel gene involved in drought tolerance, which is important for plant breeding and quality improvement for Chinese cabbage.