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.

[Application of veno-arterio-venous extracorporeal membrane oxygenation in patients with critical respiratory failure combined with refractory shock]

Objective: To preliminarily analyze the application experience of veno-arterio-venous extracorporeal membrane oxygenation (VAV-ECMO).The VAV-ECMO is a rescue strategy for patients with extremely critical respiratory failure combined with refractory shock. Methods: From February 2016 to February 2022, the characteristics and outcomes of patients who were started on either veno-venous or veno-arterial ECMO due to respiratory or hemodynamic failure, and then converted to VAV-ECMO in respiratory intensive care unit (ICU) of Beijing Chaoyang Hospital were analyzed. Results: A total of 15 patients underwent VAV-ECMO, aged 53 (40, 65) years, and 11 of whom were male. Within the group, VV-ECMO was initially used in 12 patients due to respiratory failure, but then VAV-ECMO was used due to cardiogenic shock (7/12) and septic shock (4/12), while VAV-ECMO was established in two patients due to lung transplantation. One patient was diagnosed with pneumonia complicated by septic shock, which was initially determined to be VA-ECMO, but then switched to VAV-ECMO because it was difficult to maintain oxygenation. The time from the establishment of VV or VA-ECMO to the switch to VAV-ECMO was 3 (1, 5) days and the VAV-ECMO support time was 5 (2, 8) days. ECMO-related complications were bleeding, mostly in the digestive tract (n=4) and airway hemorrhage (n=4), without intracranial hemorrhage, and poor arterial perfusion of the lower limbs (n=2). Among these 15 patients, the overall ICU mortality was 53.3%. The mortality of patients who received VAV-ECMO due to septic shock and cardiogenic shock was 100% (4/4) and 42.8% (3/7), respectively. Two patients who received VAV-ECMO due to lung transplantation all survived. Conclusion: VAV-ECMO may be a safe and effective treatment for carefully selected patients with critical respiratory failure associated with cardiogenic shock or end-stage lung disease lung transplantation transition, however, patients with septic shock may benefit the least.

[Mechanism of VPS26 gene promoting implant osseointegration through Wnt/β-catenin pathway in hyperlipidemia rats]

Objective: To investigate the mechanism of VPS26 effect on osteogenesis and adipogenesis differentiation of rat bone marrow mesenchymal stem cells (BMSC) in high fat environment, and to explore the effect of VPS26 on implants osseointegration of high fat rats and ectopic osteogenesis in nude mice. Methods: BMSC were cultured under normal osteogenic induction (osteogenic group) and high-fat osteogenic induction (high-fat group).High-fat group was transfected with VPS26 enhancer and inhibitor, and the expression levels of osteogenesis related genes and adipogenesis related genes were examined. Osteogenesis and adipogenesis of BMSC were detected by alkaline phosphatase (ALP) staining and oil red O staining after 7 and 14 days of induction.In osteogenic group,the binding of VPS26 to β-catenin was detected by immunofluorescence staining and immunoprecipitation, and dual luciferase reporter assay (TOP Flash) was used to analyze the TOP/FOP ratio. Eighteen male 12-week hyperlipidemic Wista rats (160-200 g) were implanted with implants, and six in each group were injected with VPS26 overexpression lentivirus (LV-VPS26 group), negative control lentivirus (LV-nc group) and saline (blank control group).Micro-CT analysis , HE and oil red O staining were used to evaluate the osseointegration of the implants and lipid droplets formation of the femur samples. Twenty female 6-week nude mice (30-40 g) were divided into five groups and subcutaneously implanted with osteogenic BMSC non-transfected and transfected LV-VPS26, LV-nc, shVPS26, and shscr lentivirus on the back. Samples were used to observe ectopic osteogenesis. Results: The mRNA expression levels of ALP in the high-fat group BMSC after overexpression of VPS26 (1.56±0.09) were significantly higher than those of the negative control (1.01±0.03) (t=10.09, P<0.001), while those of peroxisome proliferator-activated receptor-γ (PPAR-γ) (t=6.44, P<0.001) and fatty acid-binding protein4 (FABP4) (t=10.01, P<0.001) were lower than those of the negative control. Western blotting results showed that compared with the negative control, protein expression of ALP and Runt-related transcription gene 2 was enhanced in the high-fat group BMSC after overexpression of VPS26 while PPAR-γ and FABP4 were inhibited. ALP activity of BMSC in the high-fat group was stronger after overexpression of VPS26, and the formation of lipid droplets was weaker than that in negative control. The results of immunofluorescence, immunoprecipitation and dual luciferase reporter assays showed co-localization and interaction of VPS26 with β-catenin and a significant 43.10% increase in the TOP/FOP ratio (t=-3.17, P=0.034). VPS26 overexpression enhanced osseointegration and decreased the number of lipid droplets in high-fat rat and enhanced ectopic osteogenesis of nude mice. Conclusions: VPS26 activated osteogenesis differentiation and inhibited adipogenic differentiation of BMSCs through Wnt/β-catenin pathway, promoting osseointegration of high-fat rat implants and ectopic osteogenesis of nude mice.

Molecular characterisation and expression profile of the PRLR gene during goose ovarian follicle development

1. Although PRL-PRLR signalling plays important roles in regulating avian reproduction, there is a paucity of information regarding the functional significance of PRLR in goose ovarian follicle development.2. The full-length 2,496 bp coding sequence of PRLR was obtained from Sichuan White goose (Anser cygnoides) for the first time and was seen to encode a polypeptide containing 831 amino acids. Goose PRLR shares similar sequence characteristics and conserved functional domains to other avian species and was phylogenetically clustered into the avian clade.3. The qPCR results suggested that the mRNA levels of PRLR significantly increased in primary follicles during weeks 3 to 4 of age and were higher in secondary- than in primordial follicles at week 5 post-hatching, which suggested that the PRLR-mediated signalling could be involved in regulation of early folliculogenesis.4. The PRLR mRNA was expressed at the highest levels in the prehierarchical 8-10 mm granulosa layers throughout goose ovarian follicle development, indicating a role for PRLR in the process of follicle selection.5. PRLR mRNA was differentially expressed in the three cohorts of in vitro cultured granulosa cells harvested from different sized goose ovarian follicles, which suggested that PRLR was involved in regulating granulosa cell functions depending on the stage of follicle development. These data provide novel insights into the role of PRLR during goose ovarian follicle development, although the underlying mechanisms await further investigations.

Logistics Service Selection Strategy of Green Manufacturers in Green Low-Carbon Supply Chain

In order to analyze the logistics service mode and sales mode selection strategy, a green low-carbon supply chain consisting of a single manufacturer and a single e-commerce platform is considered. First, in the green low-carbon supply chain which consists of a direct selling channel and reselling channel, the selection strategy of the manufacturer's logistics service mode is analyzed. Second, in the green low-carbon supply chain which consists of a direct selling channel and an agency channel, the selection strategy of the manufacturer's logistics service mode is analyzed. Last, the manufacturer's sales mode is analyzed. We use the backward induction method to solve the theoretical model. This study contributes to the literature by considering the optimal decision of a green low-carbon supply chain. This study brings together the literature from streams on the selling channel selection strategy in green supply chains and the logistics service strategy in green supply chains. The impacts of the logistics service cost, the selling cost, and the green input cost coefficient on the optimal decision and the firms' profit are discussed. The result shows that in the direct selling channel and reselling channel, when the basic market demand and the logistics service level of the third-party logistics service provider are low, manufacturers will choose the e-commerce platform logistics service; in the opposite case, manufacturers will choose the third-party logistics service. In the direct selling channel and agency channels, when the logistics service level of the third-party logistics service provider is greater than or equal to a certain critical value and less than or equal to the logistics service level of the e-commerce platform, manufacturers will choose the e-commerce platform logistics service; in the opposite case, manufacturers will choose the third-party logistics service. No matter whether the manufacturer chooses the logistics service provided by the third-party logistics service provider or the logistics service provided by the e-commerce platform, the manufacturer should choose the direct selling channel and the agency channel.

Response of microbial community and biological nitrogen removal to the accumulation of nonylphenol in sequencing batch reactor

The widespread existence of nonylphenol in the environmental rendered from wastewater discharge has become a growing concern for its endocrine disrupting effects on microorganisms. In this study, the performance of nitrifying and denitrifying microbial community in a sequencing batch reactor (SBR) was investigated under different nonylphenol concentrations. The SBR was shown to be less effective in nitrogen removal at higher concentration of nonylphenol. Proteobacteria, Bacteroidetes, and Actinobacteria were characterized by 454 pyrosequencing as the dominant bacteria, nitrogen removal functional bacteria in these three phyla were inhibited by nonylphenol, and Proteobacteria and Actinobacteria were more sensitive to nonylphenol. With the accumulation of nonylphenol, the population of the most abundant denitrifying bacteria (Thauera spp.) and nitrifying bacteria (Nitrosomonas spp.) significantly reduced. Microbial diversity increased due to nonylphenol perturbation, which is indicated by the changes in microbial alpha diversity. Principal component analysis showed high similarity between microbial community in low and high concentration of nonylphenol, and the core genera involved in nitrogen removal had a low correlation with other genera shown in co-occurrence network. Moreover, linear discriminant analysis effect size analysis revealed intergroup differences in microorganisms. The mechanism of accumulated NP on the diversity and metabolism of the microbial community was examined. This paper established a theoretical foundation for the treatment of NP-containing wastewater and provided hints for further research about NP impact on biological nitrogen removal.

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Supplementary Information

The online version contains supplementary material available at 10.1007/s13762-023-04825-9.

Association of residential greenness with the risk of metabolic syndrome in Chinese older adults: a longitudinal cohort study

AIMS

We aimed to investigate the association between residential greenness and MetS in older Chinese adults.

METHODS

Longitudinal data on sociodemographic characteristics and lifestyle were collected from the Shenzhen Healthy Ageing Research (SHARE) cohort. Greenness exposure was assessed through satellite-derived Normalized Difference Vegetation Index (NDVI) values in the 250-m, 500-m, and 1250-m radius around the residential address for each participant. MetS was defined by standard guidelines for the Chinese population.

RESULTS

A total of 49,893 older Chinese adults with a mean age of 70.96 (SD = 5.26) years were included in the study. In the fully adjusted models, participants who lived in the highest quartile of NDVI_250-m, NDVI_500-m, and NDVI_1250-m had a 15% (odds ratio, OR = 0.85, 95% confidence interval, CI: 0.80-0.90), 12% (OR = 0.88, 95% CI: 0.83-0.93), and 11% (OR = 0.89, 95% CI: 0.85-0.95) lower incidence of MetS, respectively, than those living in the lowest quartile (all p-_trend < 0.01). Interactions and subgroup analyses showed that age, sex, smoking status, and drinking status were significant effect modifiers (p-_interaction for all NDVI < 0.05).

CONCLUSIONS

Residential greenness is associated with a lower risk of MetS in Chinese older adults, especially for young older adults, females, non-smokers, and non-drinkers.

Associations between residential greenness and blood lipids in Chinese elderly population

OBJECTIVE

Previous studies on residential green space were inconsistent with blood lipid levels and hyperlipidemia. Thus, our study aims to explore the relationship between urban residential greenness and the blood lipid level and hyperlipidemia of the Chinese elderly population.

METHODS

A total of 59,865 older adults were collected from the Shenzhen healthy aging Research (SHARE). Blood lipid levels [total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C)] were measured. Participants' exposure to residential greenness was measured by the satellite-based normalized difference vegetation index (NDVI). Generalized linear mixed models (GLMMs) and logistic regression were performed to assess the associations of residential greenness with lipid levels and dyslipidemia (high TG, high TC, low HDL-C, and high LDL-C).

RESULTS

Each per 1 standard deviation (SD) increase in NDVI_250-m was associated with a higher HDL-C level (β = 0.003, 95% (confidence interval, CI):0.001-0.005) and lower TG level (β = - 0.005, 95% CI - 0.141-0.121), after fully adjusting for covariates. Each increment in per interquartile range (IQR)-unit increase in NDVI_250-m was associated with lower odds of high TG (odds ratio, OR 0.94, 95% CI 0.91-0.97) and low HDL-C (OR 0.96, 95% CI 0.94-0.99). The NDVI_250-m has the highest protective effect on the incidence of high TG and low HDL-C, followed by NDVI_500-m and NDVI_1250-m. Stratified analyses showed that association between residential greenness and hyperlipidemia was modified by sex, age, BMI, household registration, and physical activity.

CONCLUSION

Higher greenness exposure was beneficially associated with lipid levels and dyslipidemia among Chinese city-dwelling older adults.

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.

Effects of deoxynivalenol on the histomorphology of the liver and kidneys and the expression of MAPKs in weaned rabbits

Deoxynivalenol (DON) is widely present in grain-based feeds and food. It has attracted great attention due to its high contamination rate and strong toxicity. The objective of this study was to analyse the toxic effects of DON on the liver and kidneys of weaned rabbits. 45 weaned male rabbits were allocated into control, low DON dose (0.5 mg/kg body weight), and high DON dose (1.5 mg/kg body weight) groups. Saline or DON was administrated intragastrically in the empty stomach of rabbits every morning. After 24 days of treatment, liver and kidney samples were collected for histological, reverse transcription-quantitative polymerase chain reaction (qRT-PCR), and immunohistochemistry analyses. Haematoxylin eosin staining showed that 0.5 mg/kg BW DON caused mild damage to the liver and kidney morphology, while 1.5 mg/kg body weight DON resulted in hepatic vacuolation and necrosis, as well as tubular stenosis and lesions. Data from qRT-PCR, Western blot, and immunohistochemistry revealed that the mRNA and protein expression and the distribution range of extracellular signal-regulated kinase, p38, and c-Jun NH2-terminal kinase were increased in the liver and kidneys. In conclusion, DON at the tested concentrations damaged the liver and kidneys of rabbits by affecting the expression of key proteins from the mitogen-activated protein kinase signalling pathway. The damage extent was proportional to the amount of DON ingested.

Study of the doubly charmed tetraquark [Formula: see text]

Quantum chromodynamics, the theory of the strong force, describes interactions of coloured quarks and gluons and the formation of hadronic matter. Conventional hadronic matter consists of baryons and mesons made of three quarks and quark-antiquark pairs, respectively. Particles with an alternative quark content are known as exotic states. Here a study is reported of an exotic narrow state in the D0D0π+ mass spectrum just below the D*+D0 mass threshold produced in proton-proton collisions collected with the LHCb detector at the Large Hadron Collider. The state is consistent with the ground isoscalar [Formula: see text] tetraquark with a quark content of [Formula: see text] and spin-parity quantum numbers JP = 1+. Study of the DD mass spectra disfavours interpretation of the resonance as the isovector state. The decay structure via intermediate off-shell D*+ mesons is consistent with the observed D0π+ mass distribution. To analyse the mass of the resonance and its coupling to the D*D system, a dedicated model is developed under the assumption of an isoscalar axial-vector [Formula: see text] state decaying to the D*D channel. Using this model, resonance parameters including the pole position, scattering length, effective range and compositeness are determined to reveal important information about the nature of the [Formula: see text] state. In addition, an unexpected dependence of the production rate on track multiplicity is observed.