Junshanyinzhen tea extract prevents obesity by regulating gut microbiota and metabolic endotoxemia in high-fat diet fed rats

Obesity is associated with gut dysbiosis and metabolic endotoxin.Junshanyinzhen tea extract(JSTE)reduced fat accumulation and body weight in obese mice.However,the effects and mechanism of JSTE in preventing obesity were unclear.Therefore,we used different doses of JSTE(75,150 and 300 mg/(kg·day))to evaluate the effect on high-fat diet(HFD)-induced rats under 8 weeks of intervention.Here,our results showed that JSTE could significantly reduce body weight gain,blood lipid levels and fat accumulation,improve fatty damage in liver tissue(P<0.05).In addition,JSTE increased the expression of intestinal tight junction proteins(P<0.05),relieved metabolic endotoxemia(P<0.05)and chronic low-grade inflammation in HFD rats.Sequencing of fecal samples showed that JSTE could effectively reverse the microbial diversity and the ratio of Firmicutes to Bacteroidetes to normal levels in HFD-fed rats.Desulfovibrioceae and Erysipelotrichaceae,which are positively related to obesity,were decreased by JSTE intervention(P<0.05).while Bifidobacteriaceae,Bacteroidaceae,Akkermansia,and Clostridium,which are negatively related to obesity,were increased.Together,these results suggested that JSTE might effectively prevent obesity by modulating gut microbiota dysbiosis,intestinal barrier dysfunction,metabolic endotoxemia and chronic low-grade infl ammation in HFD-induced rats.

Multi-scale simulation of diffusion behavior of deterrent in propellant

Concentration distribution of the deterrent in single-base propellant during the process of firing plays an important role in the ballistic properties of gun propellant in weapons. However, the diffusion coefficient calculated by molecular dynamics(MD) simulation is 6 orders of magnitude larger than the experimental values. Meanwhile, few simple and comprehensive theoretical models can explain the phenomenon and accurately predict the concentration distribution of the propellant. Herein, an onion model combining with MD simulation and finite element method of diffusion in propellants is introduced to bridge the gap between the experiments and simulations, and correctly predict the concentration distribution of deterrent. Furthermore, a new time scale is found to characterize the diffusion process. Finally, the time-and position-depended concentration distributions of dibutyl phthalate in nitrocellulose are measured by Raman spectroscopy to verify the correctness of the onion model. This work not only provides guidance for the design of the deterrent, but could be also extended to the diffusion of small molecules in polymer with different crystallinity.

Evaluating Parameterizations for Turbulent Fluxes over the Landfast Sea-Ice Surface in Prydz Bay, Antarctica

It is crucial to appropriately determine turbulent fluxes in numerical models.Using data collected in East Antarctica from 8 April to 26 November 2016,this study evaluates parameterization schemes for turbulent fluxes over the landfast seaice surface in five numerical models.The Community Noah Land Surface Model with Multi-Parameterizations Options(Noah_mp)best replicates the turbulent momentum flux,while the Beijing Climate System Model(BCC_CSM)produces the optimum sensible and latent heat fluxes.In particular,two critical issues of parameterization schemes,stability functions and roughness lengths,are investigated.Sensitivity tests indicate that roughness lengths play a decisive role in model performance.Based on the observed turbulent fluxes,roughness lengths over the landfast sea-ice surface are calculated.The results,which can provide a basis for setting up model parameters,reveal that the dynamic roughness length(z0m)increases with the increase of frictional velocity(u*)when u*≤0.4 m s^(−1) and fluctuates around 10^(−3 )m when u*>0.4 m s^(−1);thermal roughness length(z0t)is linearly related to the temperature gradient between air and sea-ice surface(ΔT)with a relation of lg(z0t)=−0.29ΔT−3.86;and the mean water vapor roughness length(z0q)in the specific humidity gradient(Δq)range ofΔq≤−0.6 g kg^(−1) is 10^(−6) m,3.5 times smaller than that in the range ofΔq˃−0.6 g kg^(−1).

异氰酸酯硬段对聚氨酯结构及性能的影响

异氰酸酯的种类和含量对所合成的聚氨酯性能有重要的影响。文中以聚四氢呋喃醚二醇(PTMG)为软段,甲苯二异氰酸酯(TDI)、二苯基甲烷二异氰酸酯(MDI)和六亚甲基二异氰酸酯(HDI)分别为硬段,采用预聚体法合成了一系列具有不同硬段及软硬段比例的聚氨酯,并通过红外光谱、小角X射线散射、动态力学热分析及热重分析等方法,研究了异氰酸酯种类及比例对聚氨酯软硬段相分离结构和性能的影响。结果表明,由柔性脂肪族异氰酸酯所合成的聚氨酯其相分离程度更大,软段和硬段所对应的玻璃化转变温度差异更大。由链段刚性较强的TDI所合成的聚氨酯相分离程度更小,软硬段的玻璃化转变温度相差不大,更适合用于阻尼吸音的聚氨酯材料。同时,提高异氰酸酯指数使硬段含量增加,链段运动更加困难,相分离程度有所降低,会使材料的力学性能有所提升,但是耐热性降低。

Characteristics of ground cracks caused by the M_(S) 6.4 Yangbi earthquake and the corresponding tectonic significance

An M_(S)6.4 earthquake occurred near Yangbi County, Dali Bai Autonomous Prefecture, Yunnan Province, at 21:48on May 21, 2021. The earthquake location is characterized by complex geological structures, with multiple active faults distributed around the epicenter that is located at the west edge of the Sichuan-Yunnan rhombic block(25.67°N, 99.87°E). A total of 42 ground cracks are found by earthquake field investigations. The cracks are mainly concentrated in the Ⅷ degree area on the west side of the Yangbi River. Among these, 9 coseismic tectonic ground cracks generated by shear fractures are found in three villages(i.e., Akechang, Meijia-Lijia, and Huajiazhuang), which are distributed along the strike of the northwest-trending linear folds, showing the tectonic characteristics of right-lateral tension or left-stepping cracks. The structural attribute of ground cracks sustains the kinematic properties of the Weixi-Qiaohou fault, namely right-lateral strike-slip.

Performance of the Yangbi M_(S)6.4 earthquake disaster in different geomorphic units in Yunnan

An M_(S)6.4 earthquake occurred in Yangbi,Yunnan province,on May 21,2021.According to related investigations,the macro-epicenter of the earthquake is 6 km northwest of Yangbi County,and the seismogenic structure is the NW-trending Weixi-Qiaohou fault.The earthquake area is located in the hinterland of the Hengduan Mountains in the northwest of Yunnan Province,a region dominated by high and medium-high mountains,with deep canyons and tectonic basins in between.Various geomorphic features are derived from drastic topographic changes and huge geological differences in the earthquake area.There are a variety of buildings in the earthquake-affected zone,including civil and brick-wood structures ones with weak seismic performance,as well as brick-concrete and frame ones with better seismic performance.This paper summarizes and analyzes different characteristics of the earthquake in different geomorphic units through field investigations of different buildings and geological disasters in the affected area.The results show that under the same earthquake intensity,the damage to most buildings(located in slope areas or rooted in weak strata)is amplified by the earthquake.The earthquake has exerted an obvious propagation effect along the direction of the seismogenic structure.Moreover,local ground fissures will aggravate the damage to the buildings even without surface dislocation.Thus,we suggest that attention should be paid to the ground fissures caused by the slope effect.The fissure areas may also be the disaster spot of collapses and landslides in case of a high-magnitude earthquake.

Engineering electronic platinum-carbon support interaction to tame carbon monoxide activation

CO oxidation has been studied for more than a century;however,molecular-level understanding of its activation protocol and related intermediates remains elusive.Here,we present a unified mechanistic and kinetic picture of various electronic metal-support interactions within platinum-carbon catalysts via in situ spectroscopic/kinetic analyses and multi-scale simulations.Transient kinetic analysis and molecular dynamics simulations with a reactive force field provided a quantitative description of the competition between the oxygen association and oxygen dissociation mechanisms tuned by the interfacial charge distribution and CO coverage.Steady-state isotopic transient kinetic analysis and density functional theory calculations revealed a simultaneous shift in the rate-determining step(RDS)from O_(2)^(*)dissociation to O^(*)and CO^(*)and O_(2)^(*)and CO^(*)association.A de novo strategy from the interfacial charge distribution to the reaction mechanism,kinetics/thermodynamics of RDS,and,ultimately,catalytic performance was developed to quantitatively map the above CO activation mechanism with an order-of-magnitude increase in reactivity.The proposed catalytic picture and de novo strategy are expected to prompt the development of theories and methodologies for heterogeneous catalysis.

Diabetes mellitus and adverse outcomes after carotid endarterectomy:A systematic review and meta-analysis

Background:There is still uncertainty regarding whether diabetes mellitus(DM)can adversely affect patients undergoing carotid endarterectomy(CEA)for carotid stenosis.The aim of the study was to assess the adverse impact of DM on patients with carotid stenosis treated by CEA.Methods:Eligible studies published between 1 January 2000 and 30 March 2023 were selected from the PubMed,EMBASE,Web of Science,CENTRAL,and ClinicalTrials databases.The short-term and long-term outcomes of major adverse events(MAEs),death,stroke,the composite outcomes of death/stroke,and myocardial infarction(MI)were collected to calculate the pooled effect sizes(ESs),95%confidence intervals(CIs),and prevalence of adverse outcomes.Subgroup analysis by asymptomatic/symptomatic carotid stenosis and insulin/noninsulin-dependent DM was performed.Results:A total of 19 studies(n=122,003)were included.Regarding the short-term outcomes,DM was associated with increased risks of MAEs(ES=1.52,95%CI:[1.15-2.01],prevalence=5.1%),death/stroke(ES=1.61,95%CI:[1.13-2.28],prevalence=2.3%),stroke(ES=1.55,95%CI:[1.16-1.55],prevalence=3.5%),death(ES=1.70,95%CI:[1.25-2.31],prevalence=1.2%),and MI(ES=1.52,95%CI:[1.15-2.01],prevalence=1.4%).DM was associated with increased risks of long-term MAEs(ES=1.24,95%CI:[1.04-1.49],prevalence=12.2%).In the subgroup analysis,DM was associated with an increased risk of short-term MAEs,death/stroke,stroke,and MI in asymptomatic patients undergoing CEA and with only short-term MAEs in the symptomatic patients.Both insulin-and noninsulin-dependent DM patients had an increased risk of short-term and long-term MAEs,and insulin-dependent DM was also associated with the short-term risk of death/stroke,death,and MI.Conclusions:In patients with carotid stenosis treated by CEA,DM is associated with short-term and long-term MAEs.DM may have a greater impact on adverse outcomes in asymptomatic patients after CEA.Insulin-dependent DM may have a more significant impact on post-CEA adverse outcomes than noninsulin-dependent DM.Whether DM management could reduce the risk of adverse outcomes after CEA requires further investigation.

Jumonji domain-containing protein family： the functions beyond lysine demethylation

Two of the unsolved but important questions in epigenetics are whether arginine demethylases （RDMs） exist and whether proteolytic cleavage of the histone tails and subsequent histone remodeling are a major epigenetic modification process. Jumonji domain （JmjC）-containing proteins have been characterized as lysine demethylases （KDMs） in a certain degree （Klose et al., 2006）. Emerging evidences indicate that they also catalyze demethylation reaction on the arginine residues and proteolytic removal of histone tails. These processes are likely associated with biological meanings.

Expression and clinical implication of PRL-1 and PRL-3 in transitional cell carcinoma of bladder

The mRNA and protein expression of phos-phatase of regenerating liver 1(PRL-1)and phosphatase of regenerating liver 3(PRL-3)in transitional cell carcinoma of bladder(BTCC)and normal epithelia of bladder was investigated,and the relationship between the BTCC and pathological changes was clarified.The expression of PRL-1 and PRL-3 mRNA was detected by using reverse transcription polymerase chain reaction(RT-PCR)in 30 cases of BTCC and 10 cases of normal bladder,and the expression of PRL-1 and PRL-3 protein was checked by using immunohistochemistry in 30 cases of BTCC and 15 cases of normal bladder.The expression levels of PRL-1 and PRL-3 mRNA and protein were higher in BTCC than those in normal bladder epithelia(P<0.05).The increased expression of PRL-1 and PRL-3 mRNA and protein was detectable in deep invasion and metastasis of BTCC(P<0.05).There was no correlation between the expres-sion of PRL-1 and PRL-3 and gender,age or recurrence of BTCC(all P>0.05).A significantly positive correlation was found between PRL-1 and PRL-3 in BTCC(P<0.05).PRL-1 and PRL-3 are expressed consistently and may contribute to the growth,differentiation,invasion and metastasis of BTCC.

On the surface fluxes characteristics and roughness lengths at Zhongshan station,Antarctica

Over Antarctica,surface fluxes play an important role in the local atmospheric dynamical processes.To reveal the surface fluxes characteristics and aerodynamic and thermal roughness lengths over Zhongshan station,Antarctica,this paper analyzes the data observed at the station during 3 March 2008 through 15 February 2009.It is found that easterlies dominated this site throughout the whole year,with a maximum(average)speed of 25(5.6)m s−1 at 3.9 m height,and the annual maximum(minimum)surface temperature reached 291.05(230.05)K,while the annual maximum(minimum)air-specific humidity was 4.1(0.05)g/kg at 3.9 m height.The maximum(minimum)values of seasonal mean temperature,humidity,each radiation components,sensible and latent heat flux occurred in summer(winter),while for the seasonal averaged wind speed andτthe minimums(maximums)appeared in summer(autumn).After comparing with a partially linear regression method for aerodynamic roughness length and four previous equations that derive thermal roughness length from surface Reynolds number,constant values of aerodynamic roughness length as 3.6×10^(−3)m and thermal roughness length as 1.2×10^(−4)m at this site were validated by using the other three level observations and suggested for future studies.

Promotion of boron phosphate on the NiMoAl catalyst for hydroprocessing FCC slurry oil

Mesoporous NiMoAl catalysts with boron phosphate(BPO4)modification were synthesized through the complete liquid-phase method.X-ray diffraction(XRD)analysis evidenced the presence of BPO4-AlOOH mixed support in these BPO4-modified NiMoAl samples.The total amount of acid sites declined,but the surface acidity was strengthened by adding BPO4 into the NiMoAl catalyst.It’s worth noting that the incorporation of BPO4 could increase the concentrations of Ni and Mo species on the catalyst surface and greatly improve the dispersion of(Ni)MoS2 active phases,as indicated by X-ray photoelectron spectroscopy(XPS)and transmission electron microscopy(TEM)measurements.The catalytic performance of these BPO_(4)-modified NiMoAl catalysts was investigated with the hydroprocessing of fluid catalytic cracking(FCC)slurry oil.The nitrogen-containing compounds removal from the oil was significantly enhanced with increasing the molar ratio of boron phosphate/aluminum.The NM-BPA(0.55)catalyst exhibited the best hydrodenitrogenation(HDN)activity,highlighting the significant impact of Mo sulfidation degree and the dispersion of active metals on HDN performance.The introduction of boron phosphate could also promote the hydrocracking activity of the NiMoAl catalyst,as demonstrated by SARA analysis and simulated distillation of liquid products.