Design,test,and verification of in-situ condition preserved coring and analysis system in lunar-based simulation environment

The lunar surface and its deep layers contain abundant resources and valuable information resources,the exploration and exploitation of which are important for the sustainable development of the human economy and society.Technological exploration and research in the field of deep space science,especially lunar-based exploration,is a scientific strategy that has been pursued in China and worldwide.Drilling and sampling are key to accurate exploration of the desirable characteristics of deep lunar resources.In this study,an in-situ condition preserved coring(ICP-Coring)and analysis system,which can be used to test drilling tools and develop effective sampling strategies,was designed.The key features of the system include:(1)capability to replicate the extreme temperature fluctuations of the lunar environment(-185 to 200℃)with intelligent temperature control;(2)ability to maintain a vacuum environment at a scale of 10^(-3) Pa,both under unloaded conditions within Ф580 mm×1000 mm test chamber,and under loaded conditions using Ф400 mm×800 mm lunar rock simulant;(3)application of axial pressures up to 4 MPa and confining pressures up to 3.5 MPa;(4)sample rotation at any angle with a maximum sampling length of 800 mm;and(5)multiple modes of rotary-percussive drilling,controlled by penetration speed and weight on bit(WOB).Experimental studies on the drilling characteristics in the lunar rock simulant-loaded state under different drill bit-percussive-vacuum environment configurations were conducted.The results show that the outgassing rate of the lunar soil simulant is greater than that of the lunar rock simulant and that a low-temperature environment contributes to a reduced vacuum of the lunar-based simulated environment.The rotary-percussive drilling method effectively shortens the sampling time.With increasing sampling depth,the temperature rise of the drilling tools tends to rapidly increase,followed by slow growth or steady fluctuations.The temperature rise energy accumulation of the drill bits under vacuum is more significant than that under atmospheric pressure,approximately 1.47 times higher.The real-time monitored drilling pressure,penetration speed and rotary torque during drilling serve as parameters for discriminating the drilling status.The results of this research can provide a scientific basis for returning samples from lunar rock in extreme lunar-based environments.

Effect of preload forces on multidimensional signal dynamic behaviours for battery early safety warning

Providing early safety warning for batteries in real-world applications is challenging.In this study,comprehensive thermal abuse experiments are conducted to clarify the multidimensional signal evolution of battery failure under various preload forces.The time-sequence relationship among expansion force,voltage,and temperature during thermal abuse under five categorised stages is revealed.Three characteristic peaks are identified for the expansion force,which correspond to venting,internal short-circuiting,and thermal runaway.In particular,an abnormal expansion force signal can be detected at temperatures as low as 42.4°C,followed by battery thermal runaway in approximately 6.5 min.Moreover,reducing the preload force can improve the effectiveness of the early-warning method via the expansion force.Specifically,reducing the preload force from 6000 to 1000 N prolongs the warning time(i.e.,227 to 398 s)before thermal runaway is triggered.Based on the results,a notable expansion force early-warning method is proposed that can successfully enable early safety warning approximately 375 s ahead of battery thermal runaway and effectively prevent failure propagation with module validation.This study provides a practical reference for the development of timely and accurate early-warning strategies as well as guidance for the design of safer battery systems.

Asymptotic solutions of the flow of a Johnson-Segalman fluid through a slowly varying pipe using double perturbation strategy

A double perturbation strategy is presented to solve the asymptotic solutions of a Johnson-Segalman （J-S） fluid through a slowly varying pipe. First, a small parameter of the slowly varying angle is taken as the small perturbation parameter, and then the second-order asymptotic solution of the flow of a Newtonian fluid through a slowly varying pipe is obtained in the first perturbation strategy. Second, the viscoelastic parameter is selected as the small perturbation parameter in the second perturbation strategy to solve the asymptotic solution of the flow of a J-S fluid through a slowly varying pipe. Finally, the parameter effects, including the axial distance, the slowly varying angle, and the Reynolds number, on the velocity distributions are analyzed. The results show that the increases in both the axial distance and the slowly varying angle make the axial velocity slow down. However, the radial velocity increases with the slowly varying angle, and decreases with the axial distance. There are two special positions in the distribution curves of the axial velocity and the radial velocity with different Reynolds numbers, and there are different trends on both sides of the special positions. The double perturbation strategy is applicable to such problems with the flow of a non-Newtonian fluid through a slowly varying pipe.

Survey and Analysis on Undergraduate Tea Consumption and Attitude towards Tea Consumption

Based on the sample survey of undergraduates from Tsinghua University, Northwest Sci-Tech University of Agriculture and Forestry, Yunnan University and Yunnan Agricultural University, this paper analyzes their tea consumption and attitude towards tea consumption. Results show that more than 50% undergraduates like drinking tea, especially green tea. They would like to accept lower price tea, prefer quality to brand, and have higher degree of approval of new methods of tea drinking and tea products. However, most undergraduates lack relevant knowledge about identifying tea quality. Finally, it presents recommendations for expanding tea consumption market among undergraduates.

Controlling the Balance of Photoluminescence and Photothermal Effect in Cyanostilbene-Based Luminescent Liquid Crystals

Molecular motions of the luminescent liquid crystals(LLCs)show a significant effect on fluorescent emission and heat generation.In this article,a series of cyanostilbene-based LLCs(CSs:CS1-6,CS1-12,CS2-6 and CS2-12)are synthesized to investigate how the pho-toluminescence and photothermal effect balanced.Among these materials,the mesogens peripheried by single alkyl chains formed enantiotropic nematic(CS1-6)or smectic C(CS1-12)phase with different alkyl tail lengths.When the single aliphatic chain is re-placed by mini-dendrons,room temperature(RT)monotropic hexagonal columnar phase(CS2-12)or molecular liquid(CS2-6)is formed.The results revealed that all these materials exhibited high efficiency emission with the highest quantum yield reaching 59.0%.The photoluminescence and photothermal effect can be effectively tuned by dispersing CSs into a commercially available RT liquid crystal matrix 8CB,which output significantly improved photothermal conversion efficiency of 63.2%.Furthermore,the pho-tothermal can rapidly trigger the Smectic A-Nematic-Isotropic sequence transitions of 8CB doped with CSs.This work paves a way of adjusting the balance of photoluminescence and photothermal properties of the LLC materials.

MALAT1 promotes platelet activity and thrombus formation through PI3k/Akt/GSK-3βsignalling pathway

Background Ischaemic stroke and other cardiovascular illnesses are characterised by abnormalities in the processes of thrombosis and haemostasis,which rely on platelet activity.In platelets,a wide variety of microRNAs(long non-coding RNA,lncRNAs)is found.Due to the absence of nuclear DNA in platelets,lncRNAs may serve as critical post-transcriptional regulators of platelet activities.However,research into the roles of lncRNAs in platelets is limited.Objective The purpose of this study is to learn more about the molecular mechanism by which MALAT1 affects platelet activity and thrombus formation.Methods/results The CD34+megakaryocytes used in this research as an in vitro model for human megakaryocytes and platelets.Cell adhesion and spreading are enhanced in the absence and presence of agonists in CD34+megakaryocytes subjected to MALAT1 knockdown(KD).The adhesion and activity of platelet-like particles produced by MALAT1 KD cells are significantly enhanced at rest and after thrombin activation.Thrombus development on a collagen matrix is also greatly enhanced in the microfluidic whole-blood perfusion model:platelets lacking MALAT1 exhibit elevated accumulation,distributing area and activity.In addition,MALAT1-deficient mice bleed less and form a stable occlusive thrombus more quickly than wild-type mice.PTEN and PDK1 regulated the activity of MALAT1 in platelets to carry out its PI3k/Akt/GSK-3βsignalling pathway-related function.Conclusion The suppression of MALAT1 expression significantly increases platelet adhesion,spreading,platelet activity,and thrombus formation.lncRNAs may constitute a unique class of platelet function modulators.

不同核酸提取方案对EB病毒核酸质量及扩增影响分析

目的通过比较不同核酸提取方法对EB病毒(EBV)-DNA检测的影响,探讨EBV-DNA检测的优化方案。方法收集16例全血EBV-DNA阳性标本(EBV-DNA浓度>1000 copies/ml),分别用手工提取法、A品牌核酸提取仪(A机)和B品牌核酸提取仪(B机)提取全血核酸,检测各样本核酸浓度及A260/A280比值,分析不同提取法所得核酸质量,再采用荧光定量PCR检测EBV-DNA浓度,比较3种核酸提取法检测EBV-DNA的差异。为探究全血与血浆检测EBV-DNA的差异,对19例手工提取后检测结果为阳性的全血标本,用试剂盒配套的血浆提取方法手工提取其血浆核酸,采用荧光定量PCR检测EBV-DNA浓度。结果16例全血EBV-DNA阳性样本经3种不同方法提取核酸后,手工提取核酸浓度均数为624 ng/μl,A机提取核酸浓度均数为141 ng/μl,B机提取核酸浓度均数为273 ng/μl。2种仪器提取法结果与手工提取法比较,均差异有统计学意义(A机P<0.05,B机P<0.01)。荧光定量PCR检测EBV-DNA浓度显示,手工提取全部为阳性,A机有4例未检测出阳性,B机有5例未检测出阳性。结果提示,低浓度EBV标本如采用该研究中的仪器提取核酸可能发生漏检。在同时检测全血与血浆的19例EBV-DNA阳性标本中,只有1例血浆阳性,全血样本EBV-DNA阳性率高于血浆样本,差异具有统计学意义(P<0.01)。经过以上验证,该单位EBV-DNA均使用全血标本通过手工提取法提取核酸进行检测。2021年1月至2022年12月共检测7945例EBV-DNA样本,阳性1160例,阳性率14.60%,与文献报告的阳性率基本符合。结论不同核酸提取方法及标本类型对EBV-DNA检测结果存在明显影响。因此,在项目应用于临床之前应做好方法学比对,与临床协商选择合适的标本类型进行检测。项目进行过程中应对检测结果进行定期评价,为临床提供准确、有效的检测结果。

高黎贡山外来植物入侵现状及管控建议

高黎贡山是中国生物多样性的关键地区,也是西南地区重要的生态安全屏障。在气候变化和人类活动等影响下,高黎贡山正面临越来越多的外来植物入侵,其生物生态安全遭受严重威胁。本研究通过系统野外调查并结合文献数据分析,揭示高黎贡山外来植物入侵现状,根据分布范围、记录频次、分布状态以及危害性划分入侵植物的入侵等级,并提出相应管控建议。结果显示,高黎贡山现有外来植物共225种,其中入侵植物214种、外来栽培植物11种;入侵植物分散于50个科,其中菊科占比最高,达到17.29%,其次是豆科(14.02%)、大戟科(7.01%)和苋科(6.54%);从地理来源看,美洲物种占比最高,达到67.76%(145种),其次是亚洲来源物种(17.76%)。根据入侵现状评估结果,1级(恶性入侵植物)和2级(严重入侵植物)入侵物种分别有15种和27种,另外还有一些物种虽然目前尚未形成明显危害,但具有较高的入侵风险。高黎贡山外来入侵植物类群组成和原产地来源复杂多样,入侵等级分布具有地域特点,应实施分类管理措施以提高管控成效。以上结果可以为更好地管理高黎贡山地区外来植物、推动高黎贡山国家公园建设提供重要参考。

The Development of a Venus Flytrap Inspired Soft Robot Driven by IPMC

In recent years,more and more creatures in nature have become the source of inspiration for people to study bionic soft robots.Many such robots appear in the public’s vision.In this paper,a Venus flytrap robot similar to the biological Venus flytrap in appearance was designed and prepared.It was mainly cast by Polydimethylsiloxane(PDMs)and driven by the flexible material of Ionic Polymer Metal Composites(IPMCs).Combining with ANSYS and related experiments,the appropriate voltage and the size of IPMC were determined.The results showed that the performance of the Venus flytrap robot was the closest to the biological Venus flytrap when the size of IPMC length,width and driving voltage reach to 3 cm,1 cm and 5.5 V,respectively.Moreover,the closing speed and angle reached 8.22°/s and 37°,respectively.Finally,the fly traps also could be opened and closed repeatedly and captured a small ball with a mass of 0.3 g firmly in its middle and tip.

Spatiotemporal regulation of ubiquitin-mediated protein degradation via upconversion optogenetic nanosystem

Protein degradation technology,which is one of the most direct and effective ways to regulate the life activities of cells,is expected to be applied to the treatment of various diseases.However,current protein degradation technologies such as some small-molecule degraders which are unable to achieve spatiotemporal regulation,making them difficult to transform into clinical applications.In this article,an upconversion optogenetic nanosystem was designed to attain accurate regulation of protein degradation.This system worked via two interconnected parts:1)the host cell expressed light-sensitive protein that could trigger the ubiquitinproteasome pathway upon blue-light exposure;2)the light regulated light-sensitive protein by changing light conditions to achieve regulation of protein degradation.Experimental results based on model protein(Green Fluorescent Protein,GFP)validated that this system could fulfill protein degradation both in vitro(both Hela and 293T cells)and in vivo(by upconversion optogenetic nanosystem),and further demonstrated that we could reach spatiotemporal regulation by changing the illumination time(0–25 h)and the illumination frequency(the illuminating frequency of 0–30 s every 1 min).We further took another functional protein(The Nonstructural Protein 9,NSP9)into experiment.Results confirmed that the proliferation of porcine reproductive and respiratory syndrome virus(PRRSV)was inhibited by degrading the NSP9 in this light-induced system,and PRRSV proliferation was affected by different light conditions(illumination time varies from 0–24 h).We expected this system could provide new perspectives into spatiotemporal regulation of protein degradation and help realize the clinical application transformation for treating diseases of protein degradation technology.