[Spatial distribution of cognitive dysfunction and its risk factors in Chinese population aged 45 years and above]

OBJECTIVE

To analyze the spatial distribution of the prevalence of cognitive dysfunction and its risk factors in Chinese population aged 45 years and above to provide evidence for formulating regional prevention and control strategies.

METHODS

The study subjects with complete cognitive function data were selected from the follow-up data of the China Health and Retirement Longitudinal Study (CHARLS) Phase IV. ArcGis 10.4 software was used for spatial analysis of the prevalence of cognitive dysfunction in the population aged 45 years and above for each province based on the geographic information system (GIS) technology.

RESULTS

In 2018, the overall prevalence of cognitive dysfunction was 33.59% (5951/17716) in individuals aged 45 and above in China. Global spatial autocorrelation analysis indicated a spatial clustering and a positive autocorrelation (P < 0.001) of the prevalence of cognitive dysfunction in the study subjects, with a Moran's I value of 0.333085. The results of local spatial autocorrelation analysis showed that the southwestern region of China was the main aggregation area of patients with cognitive dysfunction. Geographically weighted regression analysis suggested that a male gender, an advanced age, and illiteracy were the major risk factors for cognitive dysfunction (P < 0.05). These 3 risk factors showed a spatial distribution heterogeneity with greater impact in the northern, western, and northwestern regions of China, respectively.

CONCLUSION

The prevalence of cognitive dysfunction is relatively high in individuals aged 45 years and above in China. A male gender, an advanced age, and illiteracy are the major risk factors for cognitive dysfunction and show different spatial distribution patterns, with the northern, western and northwestern regions of China as the key areas for prevention and control, where the prevention and control measures should be designed based on local conditions.

[Effect of hemoperfusion on protein energy wasting and long-term prognosis in patients on maintenance hemodialysis]

Objective: To explore the effect of hemoperfusion (HP) combined with hemodialysis (HD) (HD+HP) on protein energy wasting (PEW) and long-term prognosis in patients on maintenance HD (MHD). Methods: A prospective multicenter cohort study was conducted. Adult MHD patients who completed PEW assessment and underwent regular dialysis between July 2015 and July 2021 at 23 hemodialysis centers in Guizhou Province were selected. Demographic characteristics, physical indicators, laboratory indicators, 3-day diet diary and HP treatment data of the subjects were collected. The patients were divided into different groups according to the presence or absence of HP, the frequency of HP treatment and the type of cartridge, and then relevant indicators were compared. Multivariate logistic regression model and Cox proportional regression model were used to analyze the influence of HP treatment on PEW risk in MHD patients. Meanwhile, Kaplan-Meier method was used to plot the survival curve. Results: A total of 4 623 MHD patients (2 789 males and 1 834 females) aged (53.7±15.9) years were included in the study, with a median dialysis age of 64.3 (44.3, 92.3) months. There were 3 429 (74.2%) MHD patients treated with HD+HP, and 1 194 patients (25.8%) were not treated with HP. According to the 2008 diagnostic criteria of the International Society for Renal Nutrition and Metabolism (ISRNM), the incidence of PEW was 26.0% (1 204/4 623). Multivariate logistic regression analysis showed that female (OR=2.48, 95%CI: 1.55-3.95, P<0.001), diabetes (OR=1.75, 95%CI: 1.08-2.83, P=0.024) and high-sensitivity C-reactive protein (hs-CRP) (OR=1.02, 95%CI: 1.01-1.03, P=0.003) were risk factors for PEW, while treatment with HD+HP (OR=0.51, 95%CI: 0.31-0.87, P=0.012) and elevated triglyceride levels (OR=0.62, 95%CI: 0.48-0.80, P<0.001) were protective factors. Cox hazard ratio regression showed that among different HP treatment frequencies and cartridge types, 2 times/month (HR=0.40, 95%CI: 0.17-0.95, P=0.037), 3 times/month (HR=0.44, 95%CI: 0.23-0.85, P=0.014), 4 times/month (HR=0.54, 95%CI: 0.34-0.85, P=0.008), HA130 (HR=0.57, 95%CI: 0.36-0.89, P=0.014) and HA230 (HR=0.30, 95%CI: 0.15-0.63, P=0.001) had protective effects on the occurrence of PEW in MHD patients. The all-cause mortality rate was 11.3% (521/4 623) at 33 (24, 48) months of follow-up. Kaplan-Meier analysis showed that patients undergoing 4 times/month HP treatment (χ²=36.78, P<0.001) and using HA230 (χ²=9.46, P=0.002) had the highest survival rate. Conclusion: Treatment with HD+HP is a protective factor for PEW in patients with MHD, and 4 times/month HP treatment or HA230 significantly reduces the risk of PEW and all-cause mortality in patients with MHD.

Hybrid Exercise Program Enhances Physical Fitness and Reverses Frailty in Older Adults: Insights and Predictions from Machine Learning

PURPOSE

The declining physical condition of the older adults is a pressing issue. Wu Qin Xi exercise, despite being low-intensity, is highly effective among older adults. Inspired by its characteristics, we designed a new exercise program for frail older adults, combining strength, endurance, and Wu Qin Xi. Furthermore, we employed machine learning to predict whether frailty can be reversed in older adults after the intervention.

METHODS

A total of 181 community-dwelling frail older adults aged 65 years or older participated in this single-center, randomized controlled study, with 54.7% (n=99) being female. The study assessed the effectiveness of several exercise modalities in reversing frailty. The Fried's frailty criterion was used to assess the degree of frailty of the subjects. Participants were assigned a three-digit code 001-163 and randomly assigned (1:1:1) by computer to three different groups based on the study participant number: the Wu Qin Xi group (WQX), the strength exercise mixed with endurance exercise training group (SE), and the WQXSE hybrid exercise group incorporated the above two. Body composition and frailty-related physical fitness factors were measured before and after a 24-week intervention. The measurements included Body height, Body mass, Timed Up and Go Test (TUGT), grip strength assessment (GS), 6min walk test (6 min WT), and 10 m maximum walk speed (10 m MWS). Data were analyzed using repeated measures ANOVA to determine group and time interaction effects and machine learning models were used to predict program effectiveness.

RESULTS

A total of 163 participants completed the study, with 53.9% (n=88) of them being female. The two items, 10 m maximum walking speed (10 m MWS) and grip strength, were significantly affected by the interaction of group and time. Compared to the other two groups, the WQXSE group showed the most improvement in the item 10 m MWS. In addition, following 24 weeks of training, 68 (41.7%) of the initially frail older adults had reversed their frailty status. Among them, 19 (36.5%) were in the WQX group, 24 (44.4%) were in the WQXSE group, and 25 (43.9%) were in the SE group. The stacking model exhibited superior performance when compared to other algorithms.

CONCLUSION

A hybrid exercise regimen comprising the Wu Qin Xi routine and exercises focused on both strength and endurance holds the potential to yield greater improvements in the physical fitness of older adults, as well as reducing frailty. Leveraging a stacking model, it is possible to forecast the likelihood of older adults successfully reversing their frailty status following participation in a prevention exercise program.

High Dietary Zinc Intake Is Associated with Shorter Leukocyte Telomere Length, Mediated by Tumor Necrosis Factor-α: A Study of China Adults

OBJECTIVES

Diet can influence peripheral leukocyte telomere length (LTL), and various micronutrients have been reported to correlate with it. Zinc is known for its antioxidant properties and immunomodulatory effects. However, there are few epidemiological investigations on the relationship between dietary zinc intake and LTL. This study analyzed the association between dietary zinc and LTL and the potential role of inflammation and oxidative stress among them.

DESIGN

Cross-sectional and community-based study.

SETTING AND PARTICIPANTS

599 participants from rural communities in the Changping suburb of Beijing, China, were recruited.

MEASUREMENTS

Serum lipid profile, glycosylated hemoglobin (HbA1c), oxidative stress marker, and inflammatory cytokines levels were measured. Detailed dietary data were obtained using a 24 h food recall. LTL was assessed using a real-time PCR assay. Spearman analysis, restricted cubic splines (RCS), and general linear regression models were used to determine the association between dietary zinc intake and LTL. Simple regulatory models were also applied to analyze the role of inflammation and oxidative stress among them.

RESULTS

A total of 482 subjects were ultimately included in this analysis. Spearman analysis showed that dietary zinc intake and zinc intake under energy density were negatively correlated with LTL (r=-0.142 and -0.126, all P <0.05) and positively correlated with tumor necrosis factor-α (TNF-α) (r=0.138 and 0.202, all P <0.05) while only dietary zinc without energy adjustment had a positive correlation with superoxide dismutase (SOD). RCS (P for non-linearity=0.933) and multiple linear regression (B=-0.084, P=0.009) indicated a negative linear association between dietary zinc and LTL. The adjustment of TNF-α rather than SOD could abolish the relationship. The mediation model suggested that the unfavorable effect of dietary zinc on LTL was mediated by TNF-α.

CONCLUSIONS

High dietary zinc may correlate with telomere attrition, and TNF-α can act as a mediator in this relationship. In the future, more extensive cohort studies are needed to further explore the relationship between dietary zinc and cellular aging and the specific mechanisms.

Collision-System and Beam-Energy Dependence of Anisotropic Flow Fluctuations

Elliptic flow measurements from two-, four-, and six-particle correlations are used to investigate flow fluctuations in collisions of U+U at sqrt[s_{NN}]=193  GeV, Cu+Au at sqrt[s_{NN}]=200  GeV and Au+Au spanning the range sqrt[s_{NN}]=11.5-200  GeV. The measurements show a strong dependence of the flow fluctuations on collision centrality, a modest dependence on system size, and very little if any, dependence on particle species and beam energy. The results, when compared to similar LHC measurements, viscous hydrodynamic calculations, and trento model eccentricities, indicate that initial-state-driven fluctuations predominate the flow fluctuations generated in the collisions studied.

Effect of Grain Size on the Plastic Deformation Behaviors of a Fe-18Mn-1.3Al-0.6C Austenitic Steel

Grain size is a microscopic parameter that has a significant impact on the macroscopic deformation behavior and mechanical properties of twinning induced plasticity (TWIP) steels. In this study, Fe-18Mn-1.3Al-0.6C steel specimens with different grain sizes were first obtained by combining cold rolling and annealing processes. Then the influence of grain size on the plastic deformation mechanisms was investigated by mechanical testing, X-ray diffraction-based line profile analysis, and electron backscatter diffraction. The experimental results showed that the larger grain size could effectively promote twinning during plastic straining, produce an obvious TWIP effect, and suppress the rate of dislocation proliferation. The continuous contribution of dislocation strengthening and twinning functions led to a long plateau in the work-hardening rate curve, and increased the work-hardening index and work-hardening ability. At the same time, the strain could be uniformly distributed at the grain boundaries and twin boundaries inside the grain, which effectively relieved the stress concentration at the grain boundaries and improved the plasticity of deformed samples.

Ultrasound-Assisted Preparation of Maillard Reaction Products Derived from Hydrolyzed Soybean Meal with Meaty Flavor in an Oil-In-Water System

In the present work, we prepared Maillard reaction products (MRPs) derived from enzyme hydrolyzed soybean meal with ultrasound assistance in an oil-(oxidized lard)-in-water system (UEL-MRPs) or oil-free system (UN-MRPs), and the effect of ultrasound on the properties of the obtained MRPs was evaluated. The analysis of fatty acids in lard with different treatments showed that ultrasound can generate more unsaturated fatty acids in the aqueous phase. The UV–Vis absorbances of UEL-MRPs, UN-MRPs, and MRPs obtained in an oil-in-water system (EL-MRPs) and MRPs obtained in an oil-free system (N-MRPs) at 294 and 420 nm indicated that ultrasound could increase the amount of Maillard reaction intermediates and melanoids in the final products of the Maillard reaction. This was in line with the result obtained from color change determination—that ultrasound can darken the resultant MRPs. Volatile analysis showed ultrasound can not only increase the number of volatile substances, but also greatly increase the composition of volatile substances in UEL-MRPs and UN-MRPs, especially the composition of those contributing to the flavor of the MRPs, such as oxygen-containing heterocycles, sulfur-containing compounds, and nitrogen-containing heterocycles. Descriptive sensory evaluation revealed that UN-MRPs and UEL-MRPs had the highest scores in total acceptance, ranking in the top two, and UEL-MRPs had the strongest meaty flavor among these four kinds of MRPs. Furthermore, the measurements of antioxidant activities, including DPPH radical-scavenging activity, hydroxyl radical scavenging ability, and ferric ion reducing antioxidant power, were conducted, showing that UN-MRPs exhibited the highest antioxidant activity among all the MRPs.

Symptom burden, psychological distress, and symptom management status in hospitalized patients with advanced cancer: a multicenter study in China

BACKGROUND

The management of physical symptoms and psychological distress of cancer patients is an important component of cancer care. The purpose of this study was to evaluate the symptom burden, psychological distress, and management status of hospitalized patients with advanced cancer in China and explore the potential influencing factors of undertreatment and non-treatment of symptoms.

PATIENTS AND METHODS

A total of 2930 hospitalized patients with advanced cancer (top six types of cancer in China) were recruited from 10 centers all over China. Patient-reported MD Anderson Symptom Inventory, Hospital Anxiety and Depression Scale (HADS), and Patient Health Questionnaire-9 (PHQ-9) scales and symptom management-related information were collected and linked with the patient's clinical data. The proportion of patients reporting moderate-to-severe (MS) symptoms and whether they were currently well managed were examined. Multivariable logistic regression models were applied to explore the factors correlated to undertreatment and non-treatment of symptoms.

RESULTS

About 27% of patients reported over three MS symptoms, 16% reported over five, and 9% reported over seven. Regarding psychological distress, the prevalence of HADS-anxiety was 29% and that of PHQ-9 depression was 11%. Sixty-one percent of patients have at least one MS symptom without any treatment. Sex [odds ratio (OR) = 2.238, 95% confidence interval (95% CI) 1.502-3.336], Eastern Cooperative Oncology Group (ECOG; OR = 0.404, 95% CI 0.241-0.676), and whether currently undergoing anticancer treatment (OR = 0.667, 95% CI 0.503-0.886) are the main factors correlated with the undertreatment of symptoms. Age (OR = 1.972, 95% CI 1.263-3.336), sex (OR = 0.626, 95% CI 0.414-0.948), ECOG (OR = 0.266, 95% CI 0.175-0.403), whether currently undergoing anticancer treatment (OR = 0.356, 95% CI 0.249-0.509), and comorbidity (OR = 0.713, 95% CI 0.526-0.966) are the main factors correlated with the non-treatment of symptoms.

CONCLUSIONS

This study shows that hospitalized patients with advanced cancer had a variety of physical and psychological symptoms but lacked adequate management and suggests that a complete symptom screening and management system is needed to deal with this complex problem.

[Clinical significance of autoantibodies against ubiquitin carboxyl hydrolase L1 epitopes in the screening and diagnosis of Sjögren syndrome]

Objective: To study the clinical significance of autoantibodies against different ubiquitin carboxyl hydrolase L1 (UCH-L1) epitopes in Sjogren syndrome (SS). Methods: The serum levels of different UCH-L1 epitope autoantibodies in 98 SS patients [SS group, 17 males and 81 females, aged (49.1±12.3) years] in the Fifth Affiliated Hospital of Zhengzhou University and Peking University People's Hospital from January 2017 to January 2020 and 37 healthy controls [control group, 6 males and 31 females, aged (46.3±5.8) years] were determined by enzyme-linked immunosorbent assay (ELISA). Three potential epitopes of UCH-L1 protein were analyzed and synthesized and anti-UCH-L1^203-214 and anti-UCH-L1^58-69 antibodies were studied between the two groups. The levels of the two anti-UCH-L1 antibodies in the two groups were compared. The correlation between the levels of UCH-L1 antibodies and clinical data of SS patients were analyzed by Pearson correlation analysis. Results: The serum levels of anti-UCH-L1^203-214 and anti-UCH-L1^58-69 antibody in SS patients were significantly higher than those in healthy controls (HCs) (anti-UCH-L1^203-214: 108.2±54.3 vs 78.9±25.8, P<0.001, anti-UCH-L1^58-69: 86.8±33.3 vs 60.4±21.5, P<0.001). The positive rates of anti-UCH-L1^203-214 and anti-UCH-L1^58-69 antibodies in serums of SS patients were 27.6 % (27/98) and 25.5% (25/98), and those in HCs were 2.7%(1/37) and 5.4 %(2/37), respectively. In SS patients with positive serum anti-UCH-L1^58-69 antibody, the levels of IgG, γ globulin and rheumatoid factor (RF) and anti-SS-related antigen B (anti-SSB) antibody positive rate were all significantly higher than those in patients with negative antibody (all P<0.05). In SS patients with negative antinuclear antibody (ANA), anti-RNA binding protein (anti-RNP) antibody, anti-SS-related antigen A (anti-SSA) antibody and anti-SSB antibody, the positive rates of anti-UCH-L1^203-214 antibody was 32.1%(9/28), 27.2%(25/92), 36.4%(12/33), 28.6%(18/63), respectively; and the positive rates of anti-UCH-L1^58-69 antibody was 21.4%(6/28), 30.4%(28/92), 30.3%(10/33), 20.6%(13/63), respectively. The level of serum anti-UCH-L1^203-214 antibody in SS patients was positively correlated with the IgA level (r=0.21, P=0.024). The level of anti-UCH-L1^58-69 antibody in SS patients was positively correlated with the levels of γ-globulin, IgG and RF (r=0.35, 0.33, 0.32, all P<0.01). Conclusion: Autoantibodies against UCH-L1 epitopes are correlated with some clinical parameters of SS patients, which is of promising significance in the screening and diagnosis of SS.

Evidence for Nonlinear Gluon Effects in QCD and Their Mass Number Dependence at STAR

The STAR Collaboration reports measurements of back-to-back azimuthal correlations of di-π^{0}s produced at forward pseudorapidities (2.6<η<4.0) in p+p, p+Al, and p+Au collisions at a center-of-mass energy of 200 GeV. We observe a clear suppression of the correlated yields of back-to-back π^{0} pairs in p+Al and p+Au collisions compared to the p+p data. The observed suppression of back-to-back pairs as a function of transverse momentum suggests nonlinear gluon dynamics arising at high parton densities. The larger suppression found in p+Au relative to p+Al collisions exhibits a dependence of the saturation scale Q_{s}^{2} on the mass number A. A linear scaling of the suppression with A^{1/3} is observed with a slope of -0.09±0.01.

Research progress of anthocyanin prebiotic activity: A review

BACKGROUND

Anthocyanins are a kind of flavonoids and natural water-soluble pigments, which endow fruits, vegetables, and plants with multiple colors. They are important source of new products with prebiotic activity. However, there is no systematic review documenting prebiotic activity of anthocyanins and their structural analogues. This study aims to fill this gap in literature.

PURPOSE

The objective of this review is to summarize and evaluate the prebiotic activity of anthocyanin's, and discuss the physical and molecular modification methods to improve their biological activities.

STUDY DESIGN AND METHODS

In this review, the databases (PubMed, Google Scholar, Web of Science, Researchgate and Elsevier) were searched profoundly with keywords (anthocyanin's, prebiotics, probiotics, physical embedding and molecular modification).

RESULTS

A total of 34 articles were considered for reviewing. These studies approved that anthocyanins play an important role in promoting the proliferation of probiotics, inhibiting the growth of harmful bacteria and improving the intestinal environment. In addition, physical embedding and molecular modification have also been proved to be effective methods to improve the prebiotic activity of anthocyanins. Anthocyanins could promote the production of short chain fatty acids, accelerate self degradation and improve microbial related enzyme activities to promote the proliferation of probiotics. They inhibited the growth of harmful bacteria by inhibiting the expression of harmful bacteria genes, interfering with the role of metabolism related enzymes and affecting respiratory metabolism. They promoted the formation of a complete intestinal barrier and regulated the intestinal environment to keep the body healthy. Physical embedding, including microencapsulation and colloidal embedding, greatly improved the stability of anthocyanins. On the other hand, molecular modification, especially enzymatic modification, significantly improved the biological activities (antioxidant, prebiotic activity and so on) of anthocyanins.

CONCLUSION

All these research results displayed by this review indicate that anthocyanins are a useful tool for developing prebiotic products. The better activities of the new anthocyanins formed by embedding and modification may make them become more effective raw materials. Our review provides a scientific basis for the future research and application of anthocyanins.

[Progress in the study of antiviral activity of cepharanthine against SARS-CoV-2]

As a member of the dibenzyl isoquinoline alkaloid family, cepharathine is an alkaloid from the traditional Chinese medicine cepharathine, which is mainly used for treatment of leukopenia and other diseases. Recent studies of the inhibitory effect of cepharathine against SARS-CoV-2 have attracted widespread attention and aroused heated discussion. As the original discoverer of the anti-SARS-CoV-2 activity of cepharanthine, here we briefly summarize the discovery of cepharanthine and review important progress in relevant studies concerning the discovery and validation of anti-SARS-CoV-2 activity of cepharathine, its antiviral mechanisms and clinical trials of its applications in COVID-19 therapy.

Producing beef flavors in hydrolyzed soybean meal-based Maillard reaction products participated with beef tallow hydrolysates

This work investigated the effect of oxidized beef tallow on the volatile compositions and sensory properties of soybean meal-based Maillard reaction products (MRPs). Various tallow oxidation methods included thermal treatment (TT), enzymatic hydrolysis (ET) and enzymatic hydrolysis combined with mild thermal (ETT) treatment. Results showed that all these oxidized tallow contained more types of volatile compounds than those of untreated tallow. Moreover, the composition of almost all types of volatile substances was greatly increased with the addition of the oxidized beef tallow into the hydrolyzed soybean meal-based Maillard reaction system. More importantly, the composition of oxygen-containing heterocycles (63.89 μg/mL), sulfur-containing compounds (76.64 μg/mL), and nitrogen-containing heterocycles (19.81 μg/mL) that contribute positively to sensory properties in ETT-MRPs was found to be the highest among all the MRPs. Correlation assessment revealed that ETT was closely related to the most typical volatile products and sensory attributes, indicating this approach can effectively enhance the sensory and flavor of hydrolyzed soybean meal derived MRPs.

[Establishment and clinical validation of an artificial intelligence YOLOv51 model for the detection of precancerous lesions and superficial esophageal cancer in endoscopic procedure]

Objective: To construct the diagnostic model of superficial esophageal squamous cell carcinoma (ESCC) and precancerous lesions in endoscopic images based on the YOLOv5l model by using deep learning method of artificial intelligence to improve the diagnosis of early ESCC and precancerous lesions under endoscopy. Methods: 13, 009 endoscopic esophageal images of white light imaging (WLI), narrow band imaging (NBI) and lugol chromoendoscopy (LCE) were collected from June 2019 to July 2021 from 1, 126 patients at the Cancer Hospital, Chinese Academy of Medical Sciences, including low-grade intraepithelial neoplasia, high-grade intraepithelial neoplasia, ESCC limited to the mucosal layer, benign esophageal lesions and normal esophagus. By computerized random function method, the images were divided into a training set (11, 547 images from 1, 025 patients) and a validation set (1, 462 images from 101 patients). The YOLOv5l model was trained and constructed with the training set, and the model was validated with the validation set, while the validation set was diagnosed by two senior and two junior endoscopists, respectively, to compare the diagnostic results of YOLOv5l model and those of the endoscopists. Results: In the validation set, the accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the YOLOv5l model in diagnosing early ESCC and precancerous lesions in the WLI, NBI and LCE modes were 96.9%, 87.9%, 98.3%, 88.8%, 98.1%, and 98.6%, 89.3%, 99.5%, 94.4%, 98.2%, and 93.0%, 77.5%, 98.0%, 92.6%, 93.1%, respectively. The accuracy in the NBI model was higher than that in the WLI model (P<0.05) and lower than that in the LCE model (P<0.05). The diagnostic accuracies of YOLOv5l model in the WLI, NBI and LCE modes for the early ESCC and precancerous lesions were similar to those of the 2 senior endoscopists (96.9%, 98.8%, 94.3%, and 97.5%, 99.6%, 91.9%, respectively; P>0.05), but significantly higher than those of the 2 junior endoscopists (84.7%, 92.9%, 81.6% and 88.3%, 91.9%, 81.2%, respectively; P<0.05). Conclusion: The constructed YOLOv5l model has high accuracy in diagnosing early ESCC and precancerous lesions in endoscopic WLI, NBI and LCE modes, which can assist junior endoscopists to improve diagnosis and reduce missed diagnoses.

Measurements of Proton High-Order Cumulants in sqrt[s_{NN}]=3 GeV Au+Au Collisions and Implications for the QCD Critical Point

We report cumulants of the proton multiplicity distribution from dedicated fixed-target Au+Au collisions at sqrt[s_{NN}]=3.0  GeV, measured by the STAR experiment in the kinematic acceptance of rapidity (y) and transverse momentum (p_{T}) within -0.5<y<0 and 0.4<p_{T}<2.0  GeV/c. In the most central 0%-5% collisions, a proton cumulant ratio is measured to be C_{4}/C_{2}=-0.85±0.09 (stat)±0.82 (syst), which is 2σ below the Poisson baseline with respect to both the statistical and systematic uncertainties. The hadronic transport UrQMD model reproduces our C_{4}/C_{2} in the measured acceptance. Compared to higher energy results and the transport model calculations, the suppression in C_{4}/C_{2} is consistent with fluctuations driven by baryon number conservation and indicates an energy regime dominated by hadronic interactions. These data imply that the QCD critical region, if created in heavy-ion collisions, could only exist at energies higher than 3 GeV.

Measurements of _{Λ}^{3}H and _{Λ}^{4}H Lifetimes and Yields in Au+Au Collisions in the High Baryon Density Region

We report precision measurements of hypernuclei _{Λ}^{3}H and _{Λ}^{4}H lifetimes obtained from Au+Au collisions at sqrt[s_{NN}]=3.0  GeV and 7.2 GeV collected by the STAR experiment at the Relativistic Heavy Ion Collider, and the first measurement of _{Λ}^{3}H and _{Λ}^{4}H midrapidity yields in Au+Au collisions at sqrt[s_{NN}]=3.0  GeV. _{Λ}^{3}H and _{Λ}^{4}H, being the two simplest bound states composed of hyperons and nucleons, are cornerstones in the field of hypernuclear physics. Their lifetimes are measured to be 221±15(stat)±19(syst)  ps for _{Λ}^{3}H and 218±6(stat)±13(syst)  ps for _{Λ}^{4}H. The p_{T}-integrated yields of _{Λ}^{3}H and _{Λ}^{4}H are presented in different centrality and rapidity intervals. It is observed that the shape of the rapidity distribution of _{Λ}^{4}H is different for 0%-10% and 10%-50% centrality collisions. Thermal model calculations, using the canonical ensemble for strangeness, describes the _{Λ}^{3}H yield well, while underestimating the _{Λ}^{4}H yield. Transport models, combining baryonic mean-field and coalescence (jam) or utilizing dynamical cluster formation via baryonic interactions (phqmd) for light nuclei and hypernuclei production, approximately describe the measured _{Λ}^{3}H and _{Λ}^{4}H yields. Our measurements provide means to precisely assess our understanding of the fundamental baryonic interactions with strange quarks, which can impact our understanding of more complicated systems involving hyperons, such as the interior of neutron stars or exotic hypernuclei.

Probing the Gluonic Structure of the Deuteron with J/ψ Photoproduction in d+Au Ultraperipheral Collisions

Understanding gluon density distributions and how they are modified in nuclei are among the most important goals in nuclear physics. In recent years, diffractive vector meson production measured in ultraperipheral collisions (UPCs) at heavy-ion colliders has provided a new tool for probing the gluon density. In this Letter, we report the first measurement of J/ψ photoproduction off the deuteron in UPCs at the center-of-mass energy sqrt[s_{NN}]=200  GeV in d+Au collisions. The differential cross section as a function of momentum transfer -t is measured. In addition, data with a neutron tagged in the deuteron-going zero-degree calorimeter is investigated for the first time, which is found to be consistent with the expectation of incoherent diffractive scattering at low momentum transfer. Theoretical predictions based on the color glass condensate saturation model and the leading twist approximation nuclear shadowing model are compared with the data quantitatively. A better agreement with the saturation model has been observed. With the current measurement, the results are found to be directly sensitive to the gluon density distribution of the deuteron and the deuteron breakup process, which provides insights into the nuclear gluonic structure.