Treatment with β-sitosterol ameliorates the effects of cerebral ischemia/reperfusion injury by suppressing cholesterol overload, endoplasmic reticulum stress, and apoptosis

β-Sitosterol is a type of phytosterol that occurs naturally in plants.Previous studies have shown that it has anti-oxidant,anti-hyperlipidemic,anti-inflammatory,immunomodulatory,and anti-tumor effects,but it is unknown whetherβ-sitosterol treatment reduces the effects of ischemic stroke.Here we found that,in a mouse model of ischemic stroke induced by middle cerebral artery occlusion,β-sitosterol reduced the volume of cerebral infarction and brain edema,reduced neuronal apoptosis in brain tissue,and alleviated neurological dysfunction;moreover,β-sitosterol increased the activity of oxygen-and glucose-deprived cerebral cortex neurons and reduced apoptosis.Further investigation showed that the neuroprotective effects ofβ-sitosterol may be related to inhibition of endoplasmic reticulum stress caused by intracellular cholesterol accumulation after ischemic stroke.In addition,β-sitosterol showed high affinity for NPC1L1,a key transporter of cholesterol,and antagonized its activity.In conclusion,β-sitosterol may help treat ischemic stroke by inhibiting neuronal intracellular cholesterol overload/endoplasmic reticulum stress/apoptosis signaling pathways.

Bird species composition and conservation challenges in the Gaoligong Mountains, one of the most diverse bird areas in the world

The Gaoligong Mountains(GLGM),located in southwestern China,extend north to south along the western border of the Hengduan Mountains,spanning approximately 600 km.In this study,we consolidated findings from 17 bird surveys conducted in the GLGM between 2010 and 2022.We found that the GLGM harbors tremendous bird diversity,with a total of 796 documented bird species in the region.Nearly a quarter(23.0%)of these species are listed as state key protected species or as Chinese and global threatened species.Analysis of species richness at the county level showed a decreasing trend with increasing latitude,with the greatest diversity in Yingjiang(661 species).Observations indicated that the GLGM belongs to the Oriental realm,primarily composed of bird species from southern and southwestern China.The GLGM plays an important role in avian conservation by sheltering exceptional bird diversity,providing corridors and flyways for bird migration and dispersal,and mitigating the effects of climate change.In response to the conservation needs of birds and other wildlife,the Chinese government has established numerous protected areas within the GLGM.Despite these efforts,avian conservation still faces considerable challenges in the GLGM due to limitations in the protected area network,transboundary nature of the regions,and existing gaps in monitoring and research.

Deterministic processes drive turnover-dominated beta diversity of breeding birds along the central Himalayan elevation gradient

Beta diversity,the variation of community composition among sites,bridges alpha and gamma diversity and can reveal the mechanisms of community assembly through applying distance-decay models and/or partitioning beta diversity into turnover and nestedness components from functional and phylogenetic perspectives.Mountains as the most natural experiment system provide good opportunities for exploring beta diversity patterns and the underlying ecological processes.Here,we simultaneously consider distance-decay models and multiple di-mensions of beta diversity to examine spatial variations of bird communities,and to evaluate the relative importance of niche-based and neutral community assembly mechanisms along a 3600-m elevational gradient in the central Himalayas,China.Our results showed that species turnover dominates taxonomic,functional,and phylogenetic beta diversity.We observed strongest evidence of spatial distance decays in taxonomic similarities of birds,followed by its phylogenetic and functional analogues.Turnover component was highest in taxonomic beta diversity,while nestedness component was highest in functional beta diversity.Further,all correlations of assemblage similarity with climatic distance were higher than that with spatial distances.Standardized values of overall taxonomic,functional,and phylogenetic beta diversity and their turnover components increase with increasing elevational distance,while the standardized values of taxonomic and phylogenetic nestedness decreased with increasing elevational distance.Our results highlighted the niche-based deterministic processes in shaping elevational bird diversity patterns that were determined by the relative roles of decreasing trend of environmental filtering and increasing trend of limiting similarity along elevation distances.

N-heterocyclic carbene as a promising metal-free electrocatalyst with high efficiency for nitrogen reduction to ammonia

Electrocatalytic nitrogen reduction reaction(NRR)at ambient conditions holds great promise for sustainably synthesizing ammonia(NH3),while developing highly-efficient,long-term stable,and inexpensive catalysts to activate the inert N≡N bond is a key scientific issue.In this work,on the basis of the concept"N-heterocyclic carbenes(NHCs)",we propose a carbon decorated graphitic-carbon nitride(C/g-C3N4)as novel metal-free NRR electrocatalyst by means of density functional theory(DFT)computations.Our results reveal that the introduced C atom in g-C3N4 surface can be regarded as NHCs and catalytic sites for activating N≡N bond,and are stabilized by the g-C3N4 substrate due to sterically disfavored dimerization.Especially,this NHCs-based heterogeneous catalysis can efficiently reduce the activated N2 molecule to NH3 with a low overpotential of 0.05 V via an enzymatic mechanism.Our work is the first report of NHCs-based electrocatalyst for N2 fixation,thus opening an alternative avenue for advancing sustainable NH3 production.

A Clinical and Animal Experiment Integrated Platform for Small-Molecule Screening Reveals Potential Targets of Bioactive Compounds from a Herbal Prescription Based on the Therapeutic Efficacy of Yinchenhao Tang for Jaundice Syndrome

A herbal prescription in traditional Chinese medicine(TCM)has great complexity,with multiple components and multiple targets,making it extremely challenging to determine its bioactive compounds.Yinchenhao Tang(YCHT)has been extensively used for the treatment of jaundice disease.Although many studies have examined the efficacy and active ingredients of YCHT,there is still a lack of an in-depth systematic analysis of its effective components,mechanisms,and potential targets—especially one based on clinical patients.This study established an innovative strategy for discovering the potential targets and active compounds of YCHT based on an integrated clinical and animal experiment platform.The serum metabolic profiles and constituents of YCHT in vivo were determined by ultra-performance liquid chromatography–quadrupole time-of-flight mass spectrometry(UPLC-Q-ToF-MS)-based metabolomics combined with a serum pharmacochemistry method.Moreover,a compound–target–pathway network was constructed and analyzed by network pharmacology and ingenuity pathway analysis(IPA).We found that eight active components could modulate five key targets.These key targets were further verified by enzyme-linked immunosorbent assay(ELISA),which indicated that YCHT exerts therapeutic effects by targeting cholesterol 7a-hydroxylase(CYP7A1),multidrug-resistance-associated protein 2(ABCC2),multidrug-resistance-associated protein 3(ABCC3),uridine diphosphate glucuronosyl transferase 1A1(UGT1A1),and farnesoid X receptor(FXR),and by regulating metabolic pathways including primary bile acid biosynthesis,porphyrin and chlorophyll metabolism,and biliary secretion.Eight main effective compounds were discovered and correlated with the key targets and pathways.In this way,we demonstrate that this integrated strategy can be successfully applied for the effective discovery of the active compounds and therapeutic targets of an herbal prescription.

A panoramic view of Li_(7)P_(3)S_(11) solid electrolytes synthesis, structural aspects and practical challenges for all-solid-state lithium batteries

The development of an inorganic electrochemical stable solid-state electrolyte is essentially responsible for future state-of-the-art all-solid-state lithium batteries(ASSLBs).Because of their advantages in safety,working temperature,high energy density,and packaging,ASSLBs can develop an ideal energy storage system for modern electric vehicles(EVs).A solid electrolyte(SE)model must have an economical synthesis approach,exhibit electrochemical and chemical stability,high ionic conductivity,and low interfacial resistance.Owing to its highest conductivity of 17 mS·cm^(-1),and deformability,the sulfide-based Li_(7)P_(3)S_(11) solid electrolyte is a promising contender for the high-performance bulk type of ASSLBs.Herein,we present a current glimpse of the progress of synthetic procedures,structural aspects,and ionic conductivity improvement strategies.Structural elucidation and mechanistic approaches have been extensively discussed by using various characterization techniques.The chemical stability of Li_(7)P_(3)S_(11) could be enhanced via oxide doping,and hard and soft acid/base(HSAB)concepts are also discussed.The issues to be undertaken for designing the ideal solid electrolytes,interfacial challenges,and high energy density have been discoursed.This review aims to provide a bird’s eye view of the recent development of Li_(7)P_(3)S_(11)-based solid-state electrolyte applications and explore the strategies for designing new solid electrolytes with a target-oriented approach to enhance the efficiency of high energy density allsolid-state lithium batteries.

Combination of a biopharmaceutic classification system and physiologically based pharmacokinetic models to predict absorption properties of baicalein in vitro and in vivo

Objective: To determine the in vitro and in vivo absorption properties of active ingredients of the Chinese medicine, baicalein, to enrich mechanistic understanding of oral drug absorption.Methods: The Biopharmaceutic Classification System(BCS) category was determined using equilibrium solubility, intrinsic dissolution rate, and intestinal permeability to evaluate intestinal absorption mechanisms of baicalein in rats in vitro. Physiologically based pharmacokinetic(PBPK) model commercial software GastroPlus~(TM) was used to predict oral absorption of baicalein in vivo.Results: Based on equilibrium solubility, intrinsic dissolution rate, and permeability values of main absorptive segments in the duodenum, jejunum, and ileum, baicalein was classified as a drug with low solubility and high permeability. Intestinal perfusion with venous sampling(IPVS) revealed that baicalein was extensively metabolized in the body, which corresponded to the low bioavailability predicted by the PBPK model. Further, the PBPK model predicted the key indicators of BCS, leading to reclassification as BCS-II. Predicted values of peak plasma concentration of the drug(C_(max)) and area under the curve(AUC)fell within two times of the error of the measured results, highlighting the superior prediction of absorption of baicalein in rats, beagles, and humans. The PBPK model supported in vitro and in vivo evidence and provided excellent prediction for this BCS class II drug.Conclusion: BCS and PBPK are complementary methods that enable comprehensive research of BCS parameters, intestinal absorption rate, metabolism, prediction of human absorption fraction and bioavailability, simulation of PK, and drug absorption in various intestinal segments across species. This combined approach may facilitate a more comprehensive and accurate analysis of the absorption characteristics of active ingredients of Chinese medicine from in vitro and in vivo perspectives.

Unmanned aerial vehicle based intelligent triage system in mass-casualty incidents using 5G and artificial intelligence

BACKGROUND:Rapid on-site triage is critical after mass-casualty incidents(MCIs)and other mass injury events.Unmanned aerial vehicles(UAVs)have been used in MCIs to search and rescue wounded individuals,but they mainly depend on the UAV operator’s experience.We used UAVs and artificial intelligence(AI)to provide a new technique for the triage of MCIs and more efficient solutions for emergency rescue.METHODS:This was a preliminary experimental study.We developed an intelligent triage system based on two AI algorithms,namely OpenPose and YOLO.Volunteers were recruited to simulate the MCI scene and triage,combined with UAV and Fifth Generation(5G)Mobile Communication Technology real-time transmission technique,to achieve triage in the simulated MCI scene.RESULTS:Seven postures were designed and recognized to achieve brief but meaningful triage in MCIs.Eight volunteers participated in the MCI simulation scenario.The results of simulation scenarios showed that the proposed method was feasible in tasks of triage for MCIs.CONCLUSION:The proposed technique may provide an alternative technique for the triage of MCIs and is an innovative method in emergency rescue.

Multiple extended target tracking algorithm based on Gaussian surface matrix

In this paper, we consider the problem of irregular shapes tracking for multiple extended targets by introducing the Gaussian surface matrix（GSM） into the framework of the random finite set（RFS） theory. The Gaussian surface function is constructed first by the measurements, and it is used to define the GSM via a mapping function. We then integrate the GSM with the probability hypothesis density（PHD） filter, the Bayesian recursion formulas of GSM-PHD are derived and the Gaussian mixture implementation is employed to obtain the closed-form solutions. Moreover, the estimated shapes are designed to guide the measurement set sub-partition, which can cope with the problem of the spatially close target tracking. Simulation results show that the proposed algorithm can effectively estimate irregular target shapes and exhibit good robustness in cross extended target tracking.

Uneven deposition on the Al electrode under tension strain

Structural deformation and dendrite formation, which would impact the electrochemical processes of rechargeable metal batteries, are usually observed in the high-energy density metal electrodes. Herein,we design an in-situ optical mechano-electrochemical system to study Al deposition on the Al electrode in non-aqueous Al batteries under non-uniform strain. Inhomogeneous distribution of applied strain is realized by creating an oval hole in the Al electrode. The results of the in-situ experiments suggest that the dense Al deposition, which is related to the evolution of surface morphology and increasing reactive sites, is achieved in the regions of stress concentration. The evolution of surface morphology is monitored by the in-situ tension experiments using scanning electron microscope and atomic force microscope.Besides, a qualitative mathematical model is employed to analyze the changes of the local reaction rate owing to the changed surface morphology and the cracks of oxide film under tensile stress. The results are useful to understand the Al deposition when the mechanical force is applied to the metal electrode.

The Influence of Oxygen on the Development of Nanorana parkeri Tadpoles

Ectothermic animals are tolerant of variable oxygen availability, whether low-oxygen levels constrain the fitness of ectotherms remains unclear. Nanorana parkeri, an anuran endemic to the southern Tibetan plateau, is an excellent model with which to answer this question. In this study, we raised tadpoles ofN. parkeri in oxygenated water （high-oxygen group） and deoxygenated unchlorinated tap water （low-oxygen group） and monitored their growth, mortality, and telomere length. The growth rate for body length and body weight was higher in the low-oxygen group than in the high-oxygen group. However, dissolved oxygen did not affect development time, mortality, and telomere length of the tadpoles. These results suggest that although the oxygen concentration influenced some phenotype traits of plateau tadpoles, but it didn＇t influence the telomere length and survival rate, potential explanations are the local adaptation and N. parkeri tadpoles＇ wide oxygen tolerance, and fluctuant toxic content that resulted in little oxidative stress on tadpoles. These results indicated that low oxygen was not a stress to N. parkeri tadpoles＇ fitness and survival. This study is helpful in understanding the adaptation mechanisms of Tibetan plateau amphibians.

Finite-time Mittag-Leffler synchronization of fractional-order complex-valued memristive neural networks with time delay

Without dividing the complex-valued systems into two real-valued ones, a class of fractional-order complex-valued memristive neural networks(FCVMNNs) with time delay is investigated. Firstly, based on the complex-valued sign function, a novel complex-valued feedback controller is devised to research such systems. Under the framework of Filippov solution, differential inclusion theory and Lyapunov stability theorem, the finite-time Mittag-Leffler synchronization(FTMLS) of FCVMNNs with time delay can be realized. Meanwhile, the upper bound of the synchronization settling time(SST) is less conservative than previous results. In addition, by adjusting controller parameters, the global asymptotic synchronization of FCVMNNs with time delay can also be realized, which improves and enrich some existing results. Lastly,some simulation examples are designed to verify the validity of conclusions.

Sequential vigilance is unpredictable in reproductive Black-necked Cranes

Background:Vigilance refers to the behavior of animals scanning their surroundings with a main purpose of antipredation.Whether vigilance can serve the function of anti-predation depends on its unpredictability,meaning instantaneous randomness,sequential randomness,and independence,the three assumptions from Pulliam model(J Theor Biol 38:419,1973).Here we tested two of these three assumptions in reproductive Black-necked Cranes(Grus nigricollis) in Tibetan Plateau:instantaneous randomness and sequential randomness.Methods:Observations were carried out in July and September of 2014,July and August in 2017 in Selincuo National Nature Reserve,Tibet,with the help of focal sampling method.For instantaneous randomness,we used Kolmogorov–Smirnov test for its negative exponential distribution;for sequential randomness,we used Run test,correlation analysis,and generalized linear model to see if an inter-scan and its previous scan were correlated.Results:Not similar to some recent studies,we did not find a significant predictable vigilance in this crane.Most inter-scan intervals(86/100,86.0%) passed negative exponential distribution test,meaning vigilance sequences with instantaneous randomness;most inter-scan intervals(91/100,91.0%) passed sequential random test,showing vigilance sequences were random organized.Conclusion:Our results suggest that keeping a vigilance pattern with unpredictability is beneficial to the survival of the Black-necked Cranes,which are facing with both cruel natural environments and high predation risks.

Retinal damage after exposure to white light emitting diode lights at different intensities in Sprague-Dawley rats

Background:The usage of the light emitting diode(LED)has been increasingly applied in the illumination setting and electronic equipment.However,the effect of LED lights on the retina remains unclear.In this study,we observed and analyzed the impact of white LED lights at different intensities on the function and morphology of rat retinas.Methods:Thirty-six Sprague-Dawley rats weighing 150-180 g were randomly divided into six groups(n=6 in each group)including a normal control(NC)group,4 white LED groups at different light intensities(4,000,6,000,7,000,and 10,000 lux),and an ultraviolet B(UVB)lighting group(302 nm,1,000μw/cm2).After 24 hours of continuous illumination,full-field flash electroretinogram(FERG)and pathological examination were performed in each group.Results:As revealed by FERG,the impairment of retinal function gradually worsened with the increase of LED light intensity.In contrast,the UVB group had the most severe retinal function impairment.Particularly,the functional damage of rod cells and inner nuclear layer cells was the main FERG finding in each group.In the NC group,the retina had typical morphologies featured by well-defined structures,clearly visible border between the inner and outer segments,and neatly arranged inner and outer nuclear layer cells.After 24 hours of illumination,the inner and outer parts of the retina in the 4,000 lux group were still neatly arranged,along with a clear border;however,the inner and outer nuclear layers were randomly arranged,and some irregular nuclei and cells were lost.The damage of the internal and external retinal segments and the internal and external nuclear layers became more evident in the 6,000 lux group,7,000 lux group,and 10,000 lux group.The UVB group had a more obviously disordered arrangement of inner and outer nuclear layers and loss of cells.Conclusions:Continuous exposure to white LED light can cause structural and functional damage to rat retinas,and such damage is related to the intensity of illumination.Therefore,the risk of retinal damage should be considered during LED illumination,and proper LED illumination intensity may help to maintain eye health.

基于反馈机制的高校专业课程教学方法研究——以地图制图学课程为例

目的:教学系统的核心功能在于通过反馈进行教学活动的监测与调整,而传统教学模式下相关反馈机制具有局限性,尤其是难以直接、高效地收集学生反馈信息。文章以地图制图学课程为研究对象,探讨高等教育背景下,如何通过优化反馈机制来强化专业课程的教学效果。方法:发展一套基于统计分析的教学反馈处理办法,以期为教学方法的持续优化提供科学依据。结果:这有效揭示了教学实践中的正反馈与负反馈模式。正反馈集中体现在实践操作与理论相结合的教学环节,表明这种教学方式深受学生欢迎且有利于知识掌握。相反,负反馈主要指向理论教学的抽象性和复杂性,指出学生在理解基本理论概念时遇到的挑战。结论:文章不仅证实了统计分析法在识别教学效果影响因素方面的有效性,也为后续教学策略的调整提供了明确方向。

腰椎透视穿刺封闭术联合身痛逐瘀汤热奄包对术后腰腿痛的影响

目的探讨腰椎透视穿刺封闭术联合身痛逐瘀汤热奄包对腰椎融合术后腰腿痛的治疗作用。方法将60例腰椎融合术后腰腿痛患者随机分成3组,各20例。治疗组行腰椎透视穿刺封闭术联合身痛逐瘀汤热奄包治疗,对照组A行身痛逐瘀汤热奄包治疗,对照组B行腰椎透视穿刺封闭术治疗。对比3组VAS评分和JOA评分。结果治疗前,3组VAS评分和JOA评分差异均无统计学意义(P>0.05);治疗后,3组VAS评分均比治疗前更低(P<0.05),JOA评分均比治疗前更高(P<0.05);治疗后,治疗组VAS评分比对照组A和对照组B更低(P<0.05),治疗组JOA评分比对照组A和对照组B更高(P<0.05)。结论腰椎透视穿刺封闭术联合身痛逐瘀汤热奄包治疗腰椎融合术后腰腿痛具有良好的效果。

玻璃体腔注射雷珠单抗联合超全视网膜光凝治疗视盘新生血管型糖尿病视网膜病变

目的:观察玻璃体腔注射雷珠单抗(intravitreal ranibizumab,IVR)联合超全视网膜光凝术(extra-panretinal photocoagulation,E-PRP)治疗视盘新生血管型糖尿病视网膜病变(diabetic neovascularization on the disc,DNVD)的临床疗效。方法:对临床确诊的DNVD患者32例36眼进行IVR联合E-PRP治疗。对比观察治疗前后视力、视网膜神经纤维层厚度(retinal nerve fiber layer,RNFL)、视网膜新生血管消退等情况。结果:治疗前BCVA经LogMAR转换后为0.89±0.35,治疗后6mo为0.42±0.13,与治疗前相比差异有统计学意义(P<0.01)。19眼(53%)BCVA提高2行及以上,14眼(39%)无变化,3眼(8%)视力下降>1行。IVR+E-PRP治疗后6mo时RNFL厚度为110.64±12.06μm,与治疗前及IVR治疗后7d时RNFL厚度值相比,差异均有统计学意义(t=5.612、3.304,P<0.05)。IVR+E-PRP治疗后6mo时FFA检查32眼(89%)视盘新生血管消退,4眼(11%)新生血管无变化或加重。其中25眼(69%)经过一次E-PRP有效,7眼(19%)需追加1次激光,4眼(11%)最终未能控制病情行玻璃体手术。结论:IVR联合E-PRP治疗可促使视盘新生血管消退,减轻血管渗漏和出血,提高了DNVD治疗的有效性和安全性。

酯交换法制备长链支化聚乳酸及其流变和结晶行为

在促进剂纳米氧化锌、三官能度单体季戊四醇三丙烯酸酯(PETA)的存在下,对聚乳酸(PLA)进行熔融支化改性。研究表明,PETA成功地引入到PLA分子链上,由此获得了具有长链支化(LCB)结构的聚乳酸,且未产生凝胶,熔融支化制备LCBPLA的机理为酯交换反应,并使得聚乳酸的相对分子质量分布变宽。纳米氧化锌对LCBPLA的支化有明显的促进作用,当促进剂含量为0.2 phr时,聚乳酸呈现出更低的相位角和星形支化特征,产生更明显的应变硬化,熔体强度得到显著提高,由纯PLA的0.02 N升高到0.11 N。改性PLA为线型结构与支化结构的混合物,产生了双重熔融峰,长链支化结构的引入没有改变PLA的晶体结构。虽然链段的规整性遭到了破坏,但支化大分子易于成核,等温结晶过程中晶核数量大幅提高,球晶生长速率降低,在变温结晶过程中降低了起始结晶温度,提高了结晶速率和结晶度。

TRAF6基因沉默对人视网膜母细胞瘤细胞增殖、凋亡和侵袭的影响

目的:探讨体外沉默肿瘤坏死因子受体相关因子6(TRAF6)基因对人视网膜母细胞瘤Y79细胞增殖、凋亡和侵袭的影响。方法:靶向TRAF6基因的小干扰RNA(TRAF6 siRNA)转染Y79细胞,采用qRT-PCR和Western blot法检测转染效果,MTT比色法及细胞克隆实验测定沉默TRAF6对Y79细胞增殖的影响,流式细胞术检测细胞凋亡及细胞周期,Transwell小室检测细胞迁移和侵袭能力。结果:Y79细胞经TRAF6沉默后,TRAF6 mRNA和蛋白表达水平与对照组相比均明显降低,细胞存活率、克隆形成率均明显低于对照组细胞,细胞凋亡率明显高于对照组,同时细胞周期发生明显变化,G0/G1期细胞数目增多,S和G2/M期细胞数目减少,且侵袭细胞数目、迁移细胞数目相比对照组明显减少。结论:沉默TRAF6后能显著抑制视网膜母细胞瘤Y79细胞的生长,促进肿瘤细胞的凋亡,同时抑制其侵袭和迁移能力,TRAF6可能是视网膜母细胞瘤治疗的新靶点。

EEMD和布谷鸟搜索算法优化SVR的混沌时间序列预测

为了对混沌时间序列的预测精度进行提升,提出组合预测模型,它对支持向量回归(SVR)、布谷鸟搜索(CS)与经验模态分解(EEMD)进行了综合。首先对混沌时间序列通过集合经验模态分解为一组去除噪声且相对稳定的子序列;借助CS算法对SVR参量加以优化,进而构建以SVR为基础的预测模型,由此获取原始序列的预测大小;接着以太阳黑子混沌时间序列为对象,对其进行预测实验,并与SVR、CS⁃SVR和EEMD⁃SVR的预测性能进行比较。结果显示,通过CS算法进行优化后,能够让SVR具有更快的收敛速度,使之预测精度有了明显的提升,同时也提升了它的泛化能力。