Asprosin: its function as a novel endocrine factor in metabolic-related diseases

BACKGROUND AND PURPOSE

Asprosin was discovered as a new endocrine hormone originating from fibrillin-1 cleavage that plays a crucial role in various metabolic-related diseases, such as obesity, nonalcoholic fatty liver disease (NAFLD), diabetes, polycystic ovary syndrome (PCOS), and cardiovascular diseases. The purpose of this review is to describe the recent advancements of asprosin.

METHOD

Narrative review.

RESULT

This comprehensive review explores its tissue-specific functions, focusing on white adipose tissue, liver, hypothalamus, testis, ovary, heart, pancreas, skeletal muscle, and kidney.

CONCLUSION

Asprosin is a multifaceted protein with tissue-specific roles in various physiological and pathological processes. Further research is needed to fully understand the mechanisms and potential of asprosin as a therapeutic target. These insights could provide new directions for treatments targeting metabolic-related diseases.

[Interpretation on the report of global cancer statistics 2022]

In April 2024, the World Health Organization/International Agency for Research on Cancer (IARC) published the global cancer statistics 2022 in the CA: Cancer Journal for Clinicians. This report focuses on the incidence and mortality of 36 cancers in 185 countries or territories worldwide, analyzing the differences of gender, geographic region, and the Human Development Index (HDI) level. It is estimated that in the year 2022, there were 19.96 million new cancer cases and 9.74 million cancer deaths worldwide. Lung cancer (2 480 301, 12.4%) was the most frequently diagnosed cancer in 2022, followed by female breast cancer (2 295 686, 11.5%), colorectal cancer (1 926 118, 9.6%), prostate cancer (1 466 680, 7.3%), and gastric cancer (968 350, 4.9%). Lung cancer (1 817 172, 18.7%) was also the leading cause of cancer death, followed by colorectal cancer (903 859, 9.3%), liver cancer (757 948, 7.8%), female breast cancer (665 684, 6.9%), and gastric cancer (659 853, 6.8%). With demographics-based predictions indicating that the number of new cases of cancer will reach over 35 million by 2050. The Beijing Office for Cancer Prevention and Control team has collated this report and briefly interpreted it in combination with the current situation of cancer incidence and mortality in China.

The gene CmPYL6 strongly contributes to cold tolerance in oriental melon

The current simple and crude facilities make melon production more susceptible to cold stress during off-season cultivation in China. The ABA signalling pathway is an important target for breeding cold-tolerant melon. Cold-tolerant No. 330 and cold-sensitive No. 410 oriental melon genotypes were used to analyse the relationship between ABA and cold tolerance. 12 CmPYLs, ABA receptors, were identified from the melon genome database according to sequence alignment and phylogenetic analysis. Gene function of CmPYL6 in cold tolerance was analysed using VIGS in No. 330 and overexpression in Arabidopsis WT. A total of 12 CmPYL members contain the representative domain and conserved sites. Under cold treatment, No.330 seedlings had lower electrolyte leakage and MDA content, higher ABA content and CmPYL6 expression than seedlings of No. 410. Exogenous application of ABA upregulated expression of CmPYL6 and enhanced cold tolerance of both genotypes, while inhibiting ABA accumulation reduced expression of CmPYL6 and cold tolerance of both genotypes. CmPYL6-silenced No. 330 seedlings had reduced cold tolerance, increased electrolyte leakage and MDA content as well as limited proline and soluble sugar content, while CmPYL6 overexpressed transgenic Arabidopsis plants had enhanced cold tolerance, with limited electrolyte leakage and MDA content, as well as increased proline and soluble sugar content. The CmPYL6 gene is probably an important ABA receptor in regulating cold tolerance of oriental melon. Our study provides a direction for improving breeding of cold tolerance of oriental melon.

Biological Mediators and Partial Regulatory Mechanisms on Neuropathic Pain Associated With Chemotherapeutic Agents

One of the most common issues caused by antineoplastic agents is chemotherapy-induced peripheral neuropathy (CIPN). In patients, CIPN is a sensory neuropathy accompanied by various motor and autonomic changes. With a high prevalence of cancer patients, CIPN is becoming a major problem for both cancer patients and for their health care providers. Nonetheless, there are lacking effective interventions preventing CIPN and treating the CIPN symptoms. A number of studies have demonstrated the cellular and molecular signaling pathways leading to CIPN using experimental models and the beneficial effects of some interventions on the CIPN symptoms related to those potential mechanisms. This review will summarize results obtained from recent human and animal studies, which include the abnormalities in mechanical and temperature sensory responses following chemotherapy such as representative bortezomib, oxaliplatin and paclitaxel. The underlying mechanisms of CIPN at cellular and molecular levels will be also discussed for additional in-depth studies needed to be better explored. Overall, this paper reviews the basic picture of CIPN and the signaling mechanisms of the most common antineoplastic agents in the peripheral and central nerve systems. A better understanding of the risk factors and fundamental mechanisms of CIPN is needed to develop effective preventive and therapeutic strategies.

Water uptake patterns and rooting depths of Tamarix ramosissima in the coppice dunes of the Gurbantünggüt Desert, China: a stable isotope analysis

Tamarix ramosissima has an important role in stabilizing sand dunes in desert ecosystems. Understanding the water use strategies of T. ramosissima is essential to understand its adaptations on coppice dunes. We utilized the stable isotopes δ2H and δ18O in soil water, groundwater, and xylem water to identify monthly differences in water sources. Additionally. we explored rooting depth using 2H2O as an artificial tracer. In May, T. ramosissima derived 75% of its water from shallow and middle soil layers. In July, it absorbed 90% water from middle and deep soil layers. In August and September, it acquired approximately 80% of its water from deep soil layers. The labelling using 2H as an artificial tracer indicated that the root system of T. ramosissima could reach depths >500 cm in the coppice dunes. 2H absorption was observed at depths of 100, 200, 300 and 400 cm. Soil water is the dominant water source for T. ramosissima in the coppice dunes because groundwater is at depths >30 m. The flexible water-use strategies of T. ramosissima enable it to effectively utilize different available water sources to adapt to the arid environment. These findings improve our understanding of water uptake patterns and drought adaptation strategies of T. ramosissima in the coppice dunes of desert ecosystems.

[Comparison of clinical features of septic shock in children with hematological malignancies versus children without malignant tumors]

Objective: To investigate the clinical features of septic shock in children with hematological malignancies compared with those without malignant tumor in the pediatric intensive care unit (PICU). Methods: This retrospective study enrolled children with septic shock at the PICU of Capital Institute of Pediatrics' Children's Hospital from June 2015 to July 2022. According to the presence of hematological malignancies, patients were divided into the hematological malignancies group and without malignant tumor group. Clinical data were compared between the two groups, and logistic regression analysis was used to identify related factors for mortality. Results: A total of 164 children (97 males and 67 females) with a median age of 3.6 (interquartile range 0.8, 7.8) years were enrolled, including 75 (45.7%) patients with hematological malignancies and 89 (54.3%) patients without malignant tumors. Patients in the hematological malignancies group were older [6.0(3.6, 9.4) years vs 1.2 (0.4, 4.3) years, P<0.001] and more experienced hospital-acquired infections [48.0%(36/75) vs 21.3%(19/89),P=0.001], compared with patients without malignant tumors. Surgical emergencies were more frequent in patients without malignant tumors (32.6% vs 14.7%, P=0.013). Patients with hematological malignancies mainly had blood stream infections (58.7%), with Gram-negative bacilli (46.7%), meanwhile, patients without malignant tumors more experienced Gram-positive cocci infections (22.5%) of the respiratory system (40.4%) or digestive system (28.1%). There were significant differences regarding the infection sites (P<0.001) and pathogens (P=0.001). The types of antibacterial agents (P<0.001) and the frequency of noradrenaline (P=0.013) used in patients with hematological malignancies were significantly higher than those without malignant tumors. Patients with hematological malignancies had a higher incidence of multiple organ dysfunction (MODS) [100.0%(75/75) vs 80.9%(72/89), P<0.001] and higher 28-day mortality [34.8%(23/66) vs 19.0%(15/79),P=0.048]. Multivariate logistic regression analysis showed that Pediatric Critical Illness Score (PCIS) was an independent factor for death (odds ratio, OR=1.387, 95%CI: 1.161-1.657, P<0.001) in patients with hematological malignancies, and PCIS (OR=1.419, 95%CI: 1.140-1.767, P=0.002) and the 6-hour lactate clearance rate (OR=65.857, 95%CI: 2.953-1 468.638, P=0.008) were independent factors for death in patients without malignant tumors. Conclusions: Children with hematological malignancies were older, more frequently experienced bloodstream infections, and had a higher incidence of MODS and higher 28-day mortality. PCIS is related to poor prognosis of septic shock in children.

[Association between diabetes prevalence and mortality risk in the elderly aged 60 years and above in Liaoning Province, 2017-2019]

Objective: To investigate the prevalence of diabetes in the elderly aged ≥60 years in Liaoning Province from 2017 to 2019 and analyze the impact of blood glucose control on all-cause mortality and cardiovascular disease (CVD) mortality. Methods: A survey was conducted in the elderly aged ≥60 years in Liaoning from 2017 to 2019 to collect the information about the prevalence of diabetes and other chronic diseases in the diabetes patients. The mortality of the enrolled subjects was investigated in September 2023. Cox proportional hazards regression models were used to estimate the association between blood glucose control in the elderly with diabetes and the risks of all-cause mortality and CVD mortality. Results: The crude prevalence of diabetes in the elderly aged ≥60 years was 20.2% (2 014/9 958) in Liaoning from 2017 to 2019, and the standardized prevalence rate was 19.9%. The prevalence rates of hypertension, dyslipidemia, and overweight/obesity in the diabetes patients were 77.0%, 51.7%, and 67.5% respectively. The median follow-up time was 5.5 years, and the all-cause mortality and CVD mortality rates in the diabetes patients were 244.3/10 000 person-years and 142.9/10 000 person-years, respectively. The results of the Cox proportional hazards regression model analysis showed that compared with non-diabetic individuals, diabetes patients had an increased risk of all-cause mortality by 1.68 times [hazard ratio (HR)=1.68, 95%CI: 1.44-1.94] and an increased risk of CVD mortality by 1.56 times (HR=1.56, 95%CI: 1.29-1.89). The differences in risks of all-cause mortality and CVD mortality between the diabetes patients with normal fasting blood glucose and glycated hemoglobin levels and people without diabetes were not significant (all P>0.05). The failure to meet either the FPG or HbA1c target increased the risk of all-cause mortality (all P<0.05). For individuals who failed to meet the HbA1c target, there was an increased risk of CVD mortality (all P<0.05). Conclusions: The comorbidity rate of chronic diseases was higher in the elderly with diabetes than in the elderly without diabetes in Liaoning. Elderly diabetes patients can benefit from good blood glucose control.

[Soy isoflavones alleviates calcium overload in rats with cerebral ischemia-reperfusion by inhibiting the Wnt/Ca2+ signaling pathway]

OBJECTIVE

To explore the mechanism by which soybean isoflavone (SI) reduces calcium overload induced by cerebral ischemia-reperfusion (I/R).

METHODS

Forty-eight SD rats were randomized into 4 groups to receive sham operation, cerebral middle artery occlusion for 2 h followed by 24 h of reperfusion (I/R model group), or injection of adeno-associated virus carrying Frizzled-2 siRNA or empty viral vector into the lateral cerebral ventricle after modeling.Western blotting was used to examine Frizzled-2 knockdown efficiency and changes in protein expressions in the Wnt/Ca2+ signaling pathway.Calcium levels and pathological changes in the ischemic penumbra (IP) were measured using calcium chromogenic assay and HE staining, respectively.Another 72 SD randomly allocated for sham operation, I/R modeling, or soy isoflavones pretreatment before modeling were examined for regional cerebral blood flow using a Doppler flowmeter, and the cerebral infarct volume was assessed using TTC staining.Pathologies in the IP area were evaluated using HE and Nissl staining, and ROS level, Ca2+ level, cell apoptosis, and intracellular calcium concentration were analyzed using immunofluorescence assay or flow cytometry; the protein expressions of Wnt5a, Frizzled-2, and P-CaMK Ⅱ in the IP were detected with Western blotting and immunohistochemistry.

RESULTS

In rats with cerebral I/R, Frizzled-2 knockdown significantly lowered calcium concentration (P < 0.001) and the expression levels of Wnt5a, Frizzled-2, and P-CaMK Ⅱ in the IP area.In soy isoflavones-pretreated rats, calcium concentration, ROS and MDA levels, cell apoptosis rate, cerebral infarct volume, and expression levels of Wnt/Ca2+ signaling pathway-related proteins were all significantly lower while SOD level was higher than those in rats in I/R model group.

CONCLUSION

Soy isoflavones can mitigate calcium overload in rats with cerebral I/R by inhibiting the Wnt/Ca2+ signaling pathway.

Establishment of a rabbit model of different degrees of testicular torsion

INTRODUCTION AND OBJECTIVES

Different degrees of testicular torsion result in varying degrees of testicular damage, which influences treatment options and outcomes. Therefore, establishing a testicular torsion model with different degrees is necessary for clinical diagnosis.

MATERIALS AND METHODS

Rabbits were randomly divided into four groups and their spermatic cords were twisted at 0 °, 180 °, 360 °, and 720 °, respectively. Color Doppler flow imaging (CDFI) were performed to evaluate the blood supply in testicles. The twisted testicles were surgically removed at six hours post-operation and were evaluated by morphological observation and Hematoxylin and Eosin staining.

RESULTS

CDFI signals were gradually decreased as the degree of testicular torsion increased, and scores of CDFI in the 360 ° and 720 ° groups were significantly decreased at postoperative six hours compared to pre-surgery. Compared to the sham, the testicle in the 180 ° group exhibited slight congestion, whereas the testicles in the 360 ° and 720 ° groups were dark red in color and had severe congestion and unrecognizable vessels. Hematoxylin and Eosin staining showed mild spermatogenic cell reduction and testicular interstitial hemorrhage in the 180 ° group. In the 360 ° and 720 ° groups, disordered seminiferous tubules, shed spermatogenic cells in tubules, inflammatory cell infiltration, and severe hemorrhage were found. In comparison with the sham, interstitial hemorrhage scores in the 360 ° and 720 ° groups were significantly higher, and scores of germinal epithelial cell thickness in the three testicular torsion groups were significantly decreased.

CONCLUSIONS

Collectively, we successfully constructed a testicular torsion model with different degrees in rabbits.

Modification of χ_{c1}(3872) and ψ(2S) Production in pPb Collisions at sqrt[s_{NN}]=8.16 TeV

The LHCb Collaboration measures production of the exotic hadron χ_{c1}(3872) in proton-nucleus collisions for the first time. Comparison with the charmonium state ψ(2S) suggests that the exotic χ_{c1}(3872) experiences different dynamics in the nuclear medium than conventional hadrons, and comparison with data from proton-proton collisions indicates that the presence of the nucleus may modify χ_{c1}(3872) production rates. This is the first measurement of the nuclear modification factor of an exotic hadron.

Competing risk nomogram and risk classification system for evaluating overall and cancer-specific survival in neuroendocrine carcinoma of the cervix: a population-based retrospective study

OBJECTIVE

Neuroendocrine carcinoma of the cervix (NECC) is a rare malignancy with poor clinical prognosis due to limited therapeutic options. This study aimed to establish a risk-stratification score and nomogram models to predict prognosis in NECC patients.

METHODS

Data on individuals diagnosed with NECC between 2000 and 2019 were retrieved from the Surveillance Epidemiology and End Results (SEER) database and then randomly classified into training and validation cohorts (7:3). Univariate and multivariate Cox regression analyses evaluated independent indicators of prognosis. Least absolute shrinkage and selection operator (LASSO) regression analysis further assisted in confirming candidate variables. Based on these factors, cancer-specific survival (CSS) and overall survival (OS) nomograms that predict survival over 1, 3, and 5 years were constructed. The receiver operating characteristic (ROC) curve, the concordance index (C-index), and the calibration curve estimated the precision and discriminability of the competing risk nomogram for both cohorts. Finally, we assessed the clinical value of the nomograms using decision curve analysis (DCA).

RESULTS

Data from 2348 patients were obtained from the SEER database. Age, tumor stage, T stage, N stage, chemotherapy, radiotherapy, and surgery predicted OS. Additionally, histological type was another standalone indicator of CSS prognosis. For predicting CSS, the C-index was 0.751 (95% CI 0.731 ~ 0.770) and 0.740 (95% CI 0.710 ~ 0.770) for the training and validation cohorts, respectively. Furthermore, the C-index in OS prediction was 0.757 (95% CI 0.738 ~ 0.776) and 0.747 (95% CI 0.718 ~ 0.776) for both cohorts. The proposed model had an excellent discriminative ability. Good accuracy and discriminability were also demonstrated using the AUC and calibration curves. Additionally, DCA demonstrated the high clinical potential of the nomograms for CSS and OS prediction. We constructed a corresponding risk classification system using nomogram scores. For the whole cohort, the median CSS times for the low-, moderate-, and high-risk groups were 59.3, 19.5, and 7.4 months, respectively.

CONCLUSION

New competing risk nomograms and a risk classification system were successfully developed to predict the 1-, 3-, and 5-year CSS and OS of NECC patients. The models are internally accurate and reliable and may guide clinicians toward better clinical decisions and the development of personalized treatment plans.

Filamentation of a relativistic proton bunch in plasma

We show in experiments that a long, underdense, relativistic proton bunch propagating in plasma undergoes the oblique instability, which we observe as filamentation. We determine a threshold value for the ratio between the bunch transverse size and plasma skin depth for the instability to occur. At the threshold, the outcome of the experiment alternates between filamentation and self-modulation instability (evidenced by longitudinal modulation into microbunches). Time-resolved images of the bunch density distribution reveal that filamentation grows to an observable level late along the bunch, confirming the spatiotemporal nature of the instability. We provide a rough estimate of the amplitude of the magnetic field generated in the plasma by the instability and show that the associated magnetic energy increases with plasma density.

Clustering of gout-related comorbidities and their relationship with gout flares: a data-driven cluster analysis of eight comorbidities

OBJECTIVES

To study the aggregation of multiple comorbidities in people with gout and explore differences in prognosis of gout flares among different subgroups.

METHODS

Hierarchical clustering was performed to identify homogeneous subgroups among 2639 people with gout using eight comorbidities. A one-year follow-up of acute gout flares in 463 of these people was conducted; the incidence and the timing of gout flares in each cluster were assessed to explore prognosis of gout flares. Binary logistic regression was applied to assess factors associated with gout flares.

RESULTS

In baseline study, we identified five subgroups (C1-C5). C1 (n = 671, 25%) was characterized by isolated gout with few comorbidities. C2 (n = 258, 10%) were all obese. Almost all people in C3 (n = 335, 13%) had diabetes (99.7%). All people in C4 (n = 938, 36%) had dyslipidemia. C5 (n = 437, 17%) had the highest proportion of cardiovascular disease (CVD, 53%), chronic kidney disease (CKD, 56%), and cancer (7%). In follow-up study, C5 had the highest incidence (71.9%) and earliest onset (median 3 months) of gout flares. C2 had the lowest incidence (52.1%) and the latest onset (median 10 months) of gout flares. The highest relative risk for gout recurrent was seen for C5 (OR = 2.09). Other factors associated with the risk of gout flares were age at diagnosis of gout, duration of gout, presence of tophi, and smoking ≥ 20 cigarettes/day.

CONCLUSIONS

We clustered people with gout into five groups with varying comorbidities. People with CVD, CKD, and cancer had the highest risk of gout flares and should receive comprehensive care.

Burden and trend of dietary risk-related colorectal cancer in China and its provinces: findings from the Global Burden of Disease Study 2019

OBJECTIVES

The objective of this experiment was to evaluate the spatial pattern and temporal trend of colorectal cancer (CRC) burden attributed to dietary risk factors in China from 1990 to 2019 using data from the Global Burden of Diseases, Injuries, and Risk Factors study (GBD) 2019.

METHODS

Numbers and age-standardised rates of deaths, disability-adjusted life years (DALYs) and corresponding average annual percentage change (AAPC) were determined. The joinpoint regression analysis was used to assess the temporal trends of CRC deaths and DALYs from 1990 to 2019.

RESULTS

In China, the number of diet-attributable CRC deaths and DALYs in 2019 were 90.41 (95% uncertainty interval: 65.69, 114.67) and 2234.06 (1609.96, 2831.24) per-1000 population, marking 2.05% and 1.68% annual increases since 1990, respectively. The region with the highest increase in age-standardised rates (ASRs) of diet-related CRC deaths and DALYs was in Taiwan with an AAPC of 2.00% (1.51, 2.48), whereas the highest decline in ASRs of CRC deaths and DALYs was observed in Hong Kong with an AAPC of -0.63% (-0.90, -0.35) (all P < 0.05). Nationally, men suffered higher CRC deaths and DALY burdens attributable to dietary risks than did women. Regarding the specific diet group, diets low in calcium, milk, and whole grains contributed to CRC deaths and DALYs the most.

CONCLUSIONS

Diet is an important contributor to increasing CRC burden in China. Necessary measures should be taken to kerb the growing burden attributed to dietary factors, particularly in males and in regions with middle Socio-demographic Index or lower.

Experimental Limits on Solar Reflected Dark Matter with a New Approach on Accelerated-Dark-Matter-Electron Analysis in Semiconductors

Recently a dark matter-electron (DM-electron) paradigm has drawn much attention. Models beyond the standard halo model describing DM accelerated by high energy celestial bodies are under intense examination as well. In this Letter, a velocity components analysis (VCA) method dedicated to swift analysis of accelerated DM-electron interactions via semiconductor detectors is proposed and the first HPGe detector-based accelerated DM-electron analysis is realized. Utilizing the method, the first germanium based constraint on sub-GeV solar reflected DM-electron interaction is presented with the 205.4  kg·day dataset from the CDEX-10 experiment. In the heavy mediator scenario, our result excels in the mass range of 5-15  keV/c^{2}, achieving a 3 orders of magnitude improvement comparing with previous semiconductor experiments. In the light mediator scenario, the strongest laboratory constraint for DM lighter than 0.1  MeV/c^{2} is presented. The result proves the feasibility and demonstrates the vast potential of the VCA technique in future accelerated DM-electron analyses with semiconductor detectors.

Clinicopathological features and prognostic factors of salivary gland myoepithelial carcinoma: institutional experience of 42 cases

Myoepithelial carcinoma (MECA) is a rare type of carcinoma for which the clinicopathological features and prognostic factors have not yet been fully clarified. A retrospective study of 42 patients diagnosed with salivary gland MECA was performed, focusing on the clinicopathological features and prognostic factors. Of the 42 patients, 20 died of cancer, 20 lived without tumour, one lived with distant metastasis, and one was lost to follow-up. Overall, 69.0% had tumour recurrence, 16.7% had cervical nodal metastasis, and 21.4% had distant metastasis. The 5-year overall survival rate was 70.2%. Kaplan-Meier analysis revealed that patients with pathological positive lymph nodes (pN+), multiple recurrences of tumour, and higher histological grade had worse overall survival. Multivariate Cox analysis indicated pN+ and higher histological grade to be independent predictors of decreased survival. The 5-year overall survival rate in the pN0 group was 87.5%, while that in the pN+ group was 28.6%. In conclusion, myoepithelial carcinoma can be defined as a tumour with a high incidence of recurrence and poor prognosis, especially in pN+ patients. Pathological positive lymph nodes and histological grade may serve as predictors of survival.

Amplitude Analysis of the B^{0}→K^{*0}μ^{+}μ^{-} Decay

An amplitude analysis of the B^{0}→K^{*0}μ^{+}μ^{-} decay is presented using a dataset corresponding to an integrated luminosity of 4.7  fb^{-1} of pp collision data collected with the LHCb experiment. For the first time, the coefficients associated to short-distance physics effects, sensitive to processes beyond the standard model, are extracted directly from the data through a q^{2}-unbinned amplitude analysis, where q^{2} is the μ^{+}μ^{-} invariant mass squared. Long-distance contributions, which originate from nonfactorizable QCD processes, are systematically investigated, and the most accurate assessment to date of their impact on the physical observables is obtained. The pattern of measured corrections to the short-distance couplings is found to be consistent with previous analyses of b- to s-quark transitions, with the largest discrepancy from the standard model predictions found to be at the level of 1.8 standard deviations. The global significance of the observed differences in the decay is 1.4 standard deviations.

Fraction of χ_{c} Decays in Prompt J/ψ Production Measured in pPb Collisions at sqrt[s_{NN}]=8.16 TeV

The fraction of χ_{c1} and χ_{c2} decays in the prompt J/ψ yield, F_{χ_{c}→J/ψ}=σ_{χ_{c}→J/ψ}/σ_{J/ψ}, is measured by the LHCb detector in pPb collisions at sqrt[s_{NN}]=8.16  TeV. The study covers the forward (1.5 Collapse

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Observation of Cabibbo-Suppressed Two-Body Hadronic Decays and Precision Mass Measurement of the Ω_{c}^{0} Baryon

The first observation of the singly Cabibbo-suppressed Ω_{c}^{0}→Ω^{-}K^{+} and Ω_{c}^{0}→Ξ^{-}π^{+} decays is reported, using proton-proton collision data at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.4  fb^{-1}, collected with the LHCb detector between 2016 and 2018. The branching fraction ratios are measured to be B(Ω_{c}^{0}→Ω^{-}K^{+})/B(Ω_{c}^{0}→Ω^{-}π^{+})=[6.08±0.51(stat)±0.40(syst)]%,B(Ω_{c}^{0}→Ξ^{-}π^{+})/B(Ω_{c}^{0}→Ω^{-}π^{+})=[15.81±0.87(stat)±0.44(syst)±0.16(ext)]%. In addition, using the Ω_{c}^{0}→Ω^{-}π^{+} decay channel, the Ω_{c}^{0} baryon mass is measured to be M(Ω_{c}^{0})=2695.28±0.07(stat)±0.27(syst)±0.30(ext)  MeV, improving the precision of the previous world average by a factor of 4.

Enhanced Production of Λ_{b}^{0} Baryons in High-Multiplicity pp Collisions at sqrt[s]=13 TeV

The production rate of Λ_{b}^{0} baryons relative to B^{0} mesons in pp collisions at a center-of-mass energy sqrt[s]=13  TeV is measured by the LHCb experiment. The ratio of Λ_{b}^{0} to B^{0} production cross sections shows a significant dependence on both the transverse momentum and the measured charged-particle multiplicity. At low multiplicity, the ratio measured at LHCb is consistent with the value measured in e^{+}e^{-} collisions, and increases by a factor of ∼2 with increasing multiplicity. At relatively low transverse momentum, the ratio of Λ_{b}^{0} to B^{0} cross sections is higher than what is measured in e^{+}e^{-} collisions, but converges with the e^{+}e^{-} ratio as the momentum increases. These results imply that the evolution of heavy b quarks into final-state hadrons is influenced by the density of the hadronic environment produced in the collision. Comparisons with several models and implications for the mechanisms enforcing quark confinement are discussed.

Hosing of a Long Relativistic Particle Bunch in Plasma

Experimental results show that hosing of a long particle bunch in plasma can be induced by wakefields driven by a short, misaligned preceding bunch. Hosing develops in the plane of misalignment, self-modulation in the perpendicular plane, at frequencies close to the plasma electron frequency, and are reproducible. Development of hosing depends on misalignment direction, its growth on misalignment extent and on proton bunch charge. Results have the main characteristics of a theoretical model, are relevant to other plasma-based accelerators and represent the first characterization of hosing.