Activatable fluorescent probes for imaging and diagnosis of rheumatoid arthritis

Rheumatoid arthritis(RA)is a systemic autoimmune disease that is primarily manifested as synovitis and polyarticular opacity and typically leads to serious joint damage and irreversible disability,thus adversely affecting locomotion ability and life quality.Consequently,good prognosis heavily relies on the early diagnosis and effective therapeutic monitoring of RA.Activatable fluorescent probes play vital roles in the detection and imaging of biomarkers for disease diagnosis and in vivo imaging.Herein,we review the fluorescent probes developed for the detection and imaging of RA biomarkers,namely reactive oxygen/nitrogen species(hypochlorous acid,peroxynitrite,hydroxyl radical,nitroxyl),pH,and cysteine,and address the related challenges and prospects to inspire the design of novel fluorescent probes and the improvement of their performance in RA studies.

Phase II Clinical Study of Three-Dimensional Printed Coplanar Template Combined with CT-Guided Percutaneous Core Needle Biopsy of Pulmonary Nodules in Elderly Patients

Background: As the population age structure gradually ages, more and more elderly people were found to have pulmonary nodules during physical examinations. Most elderly people had underlying diseases such as heart, lung, brain and blood vessels and cannot tolerate surgery. Computed tomography (CT)-guided percutaneous core needle biopsy (CNB) was the first choice for pathological diagnosis and subsequent targeted drugs, immune drugs or ablation treatment. CT-guided percutaneous CNB requires clinicians with rich CNB experience to ensure high CNB accuracy, but it was easy to cause complications such as pneumothorax and hemorrhage. Three-dimensional (3D) printing coplanar template (PCT) combined with CT-guided percutaneous pulmonary CNB biopsy has been used in clinical practice, but there was no prospective, randomized controlled study. Methods: Elderly patients with lung nodules admitted to the Department of Oncology of our hospital from January 2019 to January 2023 were selected. A total of 225 elderly patients were screened, and 30 patients were included after screening. They were randomly divided into experimental group (Group A: 30 cases) and control group (Group B: 30 cases). Group A was given 3D-PCT combined with CT-guided percutaneous pulmonary CNB biopsy, Group B underwent CT-guided percutaneous pulmonary CNB. The primary outcome measure of this study was the accuracy of diagnostic CNB, and the secondary outcome measures were CNB time, number of CNB needles, number of pathological tissues and complications. Results: The diagnostic accuracy of group A and group B was 96.67% and 76.67%, respectively (P = 0.026). There were statistical differences between group A and group B in average CNB time (P = 0.001), number of CNB (1 vs more than 1, P = 0.029), and pathological tissue obtained by CNB (3 vs 1, P = 0.040). There was no statistical difference in the incidence of pneumothorax and hemorrhage between the two groups (P > 0.05). Conclusions: 3D-PCT combined with CT-guided percutaneous CNB can improve the puncture accuracy of elderly patients, shorten the puncture time, reduce the number of punctures, and increase the amount of puncture pathological tissue, without increasing pneumothorax and hemorrhage complications. We look forward to verifying this in a phase III randomized controlled clinical study. .

Non-flammable long chain phosphate ester based electrolyte via competitive solventized structures for high-performance lithium metal batteries

Safety remains a persistent challenge for high-energy-density lithium metal batteries(LMBs).The development of safe and non-flammable electrolytes is especially important in harsh conditions such as high temperatures.Herein,a flame-retardant,low-cost and thermally stable long chain phosphate ester based(tributyl phosphate,TBP)electrolyte is reported,which can effectively enhance the cycling stability of highly loaded high-nickel LMBs with high safety through co-solvation strategy.The interfacial compatibility between TBP and electrode is effectively improved using a short-chain ether(glycol dimethyl ether,DME),and a specially competitive solvation structure is further constructed using lithium borate difluorooxalate(LiDFOB)to form the stable and inorganic-rich electrode interphases.Benefiting from the presence of the cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)enriched with LiF and Li_(x)PO_(y)F_(z),the electrolyte demonstrates excellent cycling stability assembled using a 50μm lithium foil anode in combination with a high loading NMC811(15.4 mg cm^(-2))cathode,with 88%capacity retention after 120 cycles.Furthermore,the electrolyte exhibits excellent high-temperature characteristics when used in a 1-Ah pouch cell(N/P=0.26),and higher thermal runaway temperature(238℃)in the ARC(accelerating rate calorimeter)demonstrating high safety.This novel electrolyte adopts long-chain phosphate as the main solvent for the first time,and would provide a new idea for the development of extremely high safety and high-temperature electrolytes.

Effects of conductive agent type on lithium extraction from salt lake brine with LiFePO_(4) electrodes

Electrochemical lithium extraction from salt lakes is an effective strategy for obtaining lithium at a low cost.Nevertheless,the elevated Mg:Li ratio and the presence of numerous coexisting ions in salt lake brines give rise to challenges,such as prolonged lithium extraction periods,diminished lithium extraction efficiency,and considerable environmental pollution.In this work,Li FePO4(LFP)served as the electrode material for electrochemical lithium extraction.The conductive network in the LFP electrode was optimized by adjusting the type of conductive agent.This approach resulted in high lithium extraction efficiency and extended cycle life.When the single conductive agent of acetylene black(AB)or multiwalled carbon nanotubes(MWCNTs)was replaced with the mixed conductive agent of AB/MWCNTs,the average diffusion coefficient of Li+in the electrode increased from 2.35×10^(-9)or 1.77×10^(-9)to 4.21×10^(-9)cm^(2)·s^(-1).At the current density of 20 mA·g^(-1),the average lithium extraction capacity per gram of LFP electrode increased from 30.36 mg with the single conductive agent(AB)to 35.62 mg with the mixed conductive agent(AB/MWCNTs).When the mixed conductive agent was used,the capacity retention of the electrode after 30 cycles reached 82.9%,which was considerably higher than the capacity retention of 65.8%obtained when the single AB was utilized.Meanwhile,the electrode with mixed conductive agent of AB/MWCNTs provided good cycling performance.When the conductive agent content decreased or the loading capacity increased,the electrode containing the mixed conductive agent continued to show excellent electrochemical performance.Furthermore,a self-designed,highly efficient,continuous lithium extraction device was constructed.The electrode utilizing the AB/MWCNT mixed conductive agent maintained excellent adsorption capacity and cycling performance in this device.This work provides a new perspective for the electrochemical extraction of lithium using LFP electrodes.

Concentrated ternary ether electrolyte allows for stable cycling of a lithium metal battery with commercial mass loading high-nickel NMC and thin anodes

A new concentrated ternary salt ether-based electrolyte enables stable cycling of lithium metal battery(LMB)cells with high-mass-loading(13.8 mg cm^(−2),2.5 mAh cm^(−2))NMC622(LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2))cathodes and 50μm Li anodes.Termed“CETHER-3,”this electrolyte is based on LiTFSI,LiDFOB,and LiBF4 with 5 vol%fluorinated ethylene carbonate in 1,2-dimethoxyethane.Commer-cial carbonate and state-of-the-art binary salt ether electrolytes were also tested as baselines.With CETHER-3,the electrochemical performance of the full-cell battery is among the most favorably reported in terms of high-voltage cycling stability.For example,LiNi_(x)Mn_(y)Co_(1-x-y)O_(2)(NMC)-Li metal cells retain 80%capacity at 430 cycles with a 4.4 V cut-off and 83%capacity at 100 cycles with a 4.5 V cut-off(charge at C/5,discharge at C/2).According to simulation by density functional theory and molecular dynamics,this favorable performance is an outcome of enhanced coordination between Li^(+)and the solvent/salt molecules.Combining advanced microscopy(high-resolution transmission electron microscopy,scanning electron microscopy)and surface science(X-ray photoelectron spectroscopy,time-of-fight secondary ion mass spectroscopy,Fourier-transform infrared spectroscopy,Raman spectroscopy),it is demonstrated that a thinner and more stable cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)are formed.The CEI is rich in lithium sulfide(Li_(2)SO_(3)),while the SEI is rich in Li_(3)N and LiF.During cycling,the CEI/SEI suppresses both the deleterious transformation of the cathode R-3m layered near-surface structure into disordered rock salt and the growth of lithium metal dendrites.

HEC-HMS模型在四川省清溪河流域山洪预报中的应用

山洪灾害往往给山区人民生命财产、自然环境等造成了极大的损害,降低山洪灾害的有效途径之一是实现基于降雨径流模型的实时预报预警系统。选取四川省山洪易发流域-清溪河流域为研究区,通过GIS技术,结合流域DEM、土壤及土地利用数据提取流域信息,构建HEC-HMS降雨-径流模型进行流域山洪预报。根据降雨径流形成过程,分别采用SCS-CN曲线法、SCS单位线法、指数退水法和马斯京根法进行计算产流、坡面汇流、基流和河道汇流四个部分。选取6场洪水进行模型参数的率定,4场洪水进行模型验证。模拟结果表明:Nash效率系数均值为0.792,相关系数均值为0.84,峰现时差均在3 h以内,合格率为90%,该模型对清溪河山洪预报具有较好适应性,可为四川省中小河流域山洪预报提供借鉴和参考。

三种常用水质评价方法的对比分析研究

简单介绍了国内常用的评价河流水质的单因子评价法、内梅罗污染指数法以及国际上常用的评价饮用水水质的加拿大水质指数(CCME WQI)法,并以四川省金堂县境内的沱江水系为例,进行实例分析。结果表明:就评价方法而言,单因子评价法和内梅罗污染指数法的评价结果均会受极端指标的影响,而CCME WQI法考虑了"范围、频率、振幅"3个因素的共同作用,能够很好地平抑极端指标的影响,同时,CCME WQI法还能利用水质指数值对水体进行分级,是一种比较全面的水质评价方法;就评价指标而言,不同指标的选择会对评价结果产生一定影响,亟须建立完善的评价指标体系,根据不同的需求选用不同的子指标体系,并由此得到不同的子指数或等级来进行水质评价。

金沙江上游近60年径流变化对气候的响应

利用金沙江上游1954年~2013年的径流资料及相应的气象资料,运用线性回归、5a滑动平均、M-K突变分析、累积距平等方法探究了金沙江上游径流的变化特点及其与当地气候之间的联系。分析表明,1954年~2013年间上游年径流量呈微弱的下降趋势,而年降雨量和年平均气温均呈明显的增加趋势;年径流量、年降雨量与年平均气温在分析时段内均无突变点;年降雨与径流呈显著正相关,而气温对径流量的影响比较小。气候变化对该区域径流变化的影响十分显著。

基于能值的成都市水资源生态经济系统可持续性研究

基于能值理论,构建了成都市水资源生态经济系统可持续发展评价体系,评估了成都市2008年~2015年的经济发展状况、水资源开发利用状况以及系统的可持续发展状况。结果表明,成都市近年来的经济发展主要依赖于不可更新资源的消耗以及反馈输入能值的投入,可更新资源投入尤其是水资源投入的比重逐渐减小;水资源能值利用强度以及人均水资源能值用量逐年减小,与其经济发展水平不相匹配,系统的可持续发展水平较低。因此,成都市应积极调整产业结构,适当加大水资源等可更新资源的投入,以实现系统的可持续发展。

基于水质-水量-水源地耦合模型的生态补水量研究

为研究受损河流生态修复所需的补水量,基于QUAL-2K水质模型模拟断面水质,Tennant法确定河道生态流量,构建了以水质达标、生态水量达标、对水源地影响最小为目标的耦合模型,并将耦合模型应用于四川省某中小河流,在水质目标下,通过对河流现状水质因子评价分析,选取氨氮、总磷两种水质因子达到Ⅲ类水为目标,对该河流出境断面水质进行模拟;水量目标下,以多年平均流量的30%和50%分别作为非汛期和汛期的生态流量;水源地目标下,生态补水不应侵占水源地本身生态流量和其他用水户用水。结果表明,水质目标下全年引水量为7 197万m^(3),水量目标下全年引水量为6 808万m^(3),综合水源地可引水量,确定补水月份为1-6月,全年引水量为1.01亿m^(3)。研究成果证明生态补水可作为短期内改善因缺水而受损的生态系统的一种手段,能够为跨区补水河流项目生态补水量的确定提供决策依据。

Liuweiwuling tablets attenuate acetaminophen-induced acute liver injury and promote liver regeneration in mice

AIM: To explore the mechanism of protection against acetaminophen-induced acute liver injury by Liuweiwuling tablets.METHODS: Intraperitoneal injections of acetaminophen(250 mg/kg) were used to induce acute liver injury in male C57BL/6 mice.A total of 24 healthy mice were randomly assigned to two groups: an acute liver injury group(control group) and a Liuweiwuling tablet group.Mice were given Liuweiwuling tablets or a vehicle(PBS) orally prior to the administration of acetaminophen.Serum alanine aminotransferase(ALT) and aspartate aminotransaminase(AST) levels were measured at different time points within one week,and pathological examinations of liver tissues were performed 36 h after induction of acute liver injury.Serum inflammatory cytokines,such as high mobility group box protein B1(HMGB1),tumor necrosis factor(TNF)-α and interleukin IL-1b,were detected using an ELISA method according to the manufacturer's instructions.Hepatic morphological changes at 36 h were assessed by hematoxylin and eosin staining.Expression of proliferating cell nuclear antigen(PCNA) in liver tissue was determined by Western blot analysis.The m RNA levels of hepatocyte proliferation markers(PCNA,Cyclin D1 and p21) were detected by real-time quantitative reverse transcription-polymerase chain reaction.RESULTS: The levels of ALT/AST in the Liuweiwuling tablet group were decreased significantly at 6,12 and 24 h compared to that of the control group(654.38 ± 120.87 vs 1566.17 ± 421.64,1154.18 ± 477.72 vs 4654.84 ± 913.71 and 935.13 ± 252.34 vs 4553.75 ± 727.37,P < 0.01).Serum HMGB1 levels at 6 and 12 h for the Liuweiwuling tablet group were significantly lower than those of the control group(23.49 ± 3.89 vs58.6 ± 3.65,61.62 ± 13.07 vs 27.32 ± 5.97,P < 0.01).Furthermore,serum TNF-α and IL-1b levels at 12 h in the Liuweiwuling tablet group were also significantly lower than those of the control group(299.35 ± 50.61 vs 439.03 ± 63.59,57.42 ± 12.98 vs 160.07 ± 49.87,P < 0.01).Centrilobular necrosis was evident in liver tissue of mice with acetaminophen-induced acute liver injury,but was almost abolished in the Liuweiwuling tablet group.The expression levels of PCNA and Cyclin D1 were up-regulated in liver tissue in the Liuweiwuling tablet group(321.08 ± 32.87 vs 157.91 ± 21.52,196.37 ± 25.39 vs 68.72 ± 11.27,P < 0.01); however,expression of p21 in liver tissue was downregulated compared to that of the control group(40.26 ± 9.97 vs 138.24 ± 13.66,P < 0.01).CONCLUSION: Liuweiwuling tablets can attenuate acute liver injury by decreasing inflammatory cytokine(HMGB1,TNF-α and IL-1b) levels and promoting liver regeneration.

Inhibition of sphingosine kinase 1 ameliorates acute liver failure by reducing high-mobility group box 1 cytoplasmic translocation in liver cells

AIM: To determine the therapeutic potential of sphingosine kinase 1(Sphk1) inhibition and its underlying mechanism in a well-characterized mouse model of D-galactosamine(D-Gal N)/lipopolysaccharide(LPS)-induced acute liver failure(ALF).METHODS: Balb/c mice were randomly assigned to different groups,with ALF induced by intraperitoneal injection of D-Ga IN(600 mg/kg) and LPS(10 μg/kg). The Kaplan-Meier method was used for survival analysis. Serum alanine aminotransferase(ALT) and aspartate aminotransferase(AST) levels at different time points within one week were determined using a multi-parametric analyzer. Serum high-mobility group box 1(HMGB1),tumor necrosis factor-α(TNF-α),interleukin(IL)-1β,IL-6,IL-10,and sphingosine-1-phosphate were detected by enzyme-linked immunosorbent assay. Hepatic morphological changes at 36 h after acute liver injury induction were assessed by hematoxylin and eosin staining. HMGB1 expression in hepatocytes and cytoplasmic translocation were detected by immunohistochemistry. Expression of Sphk1 in liver tissue and peripheral blood mononuclear cells(PBMCs) was analyzed by Western blot.RESULTS: The expression of Sphk1 in liver tissue and PBMCs was upregulated in Gal N/LPS-induced ALF. Upregulated Sphk1 expression in liver tissue was mainly caused by Kupffer cells,the resident macrophages of the liver. The survival rates of mice in the N,Ndimethylsphingosine(DMS,a specific inhibitor of Sph K1) treatment group were significantly higher than that of the control group(P < 0.001). DMS treatment significantly decreased the levels of serum ALT and AST at 6,12,and 24 h compared with that of the control group(P < 0.01 for all). Serum HMGB1 levels at 6,12,and 24 h,as well as serum TNF-α,IL-6,and IL-1β levels at 12 h,were significantly lower in the DMS treatment group than in the control group(P < 0.01 for all). Furthermore,hepatic inflammation,necrosis,and HMGB1 cytoplasm translocation in liver cells were significantly decreased in the DMS treatment group compared to the control group(43.72% ± 5.51% vs 3.57% ± 0.83%,χ2 = 12.81,P < 0.01).CONCLUSION: Inhibition of Sph K1 ameliorates ALF by reducing HMGB1 cytoplasmic translocation in liver cells,and so might be a potential therapeutic strategy for this disease.

成都市活水公园低影响开发径流效应两种方法对比分析

以成都市活水公园低影响改造为研究示例,运用推理公式和SWMM 2种方法,对比分析设计降雨下的径流总量控制率、径流峰值流量削减率和径流峰值延迟时间等因素。结果表明:低影响改造后的活水公园对径流效应的控制效果较好,对水文过程有明显的缓解作用;2种方法在小尺度范围海绵公园的适用性均较好,分析计算结果能够达到实践需求,具有可重复性;推理公式适用于缺乏实测资料情况,计算简便,可操作性强,但具有一定局限,无法处理复杂降雨数据;模型模拟适用于监测数据充足情况,可以更加细致完整地模拟出整个水文过程,其计算结果更为准确,模拟更加灵活。

Sphingosine kinase 1 dependent protein kinase C-δ activation plays an important role in acute liver failure in mice

AIM: To investigate the role of protein kinase C(PKC)-δ activation in the pathogenesis of acute liver failure(ALF) in a well-characterized mouse model of D-galactosamine(D-Gal N)/lipopolysaccharide(LPS)-induced ALF.METHODS: BALB/c mice were randomly assigned to five groups, and ALF was induced in mice by intraperitoneal injection of D-Ga IN(600 mg/kg) and LPS(10 μg/kg). Kaplan-Meier method was used for survival analysis. Serum alanine aminotransferase(ALT) and aspartate aminotransferase(AST) levels at different time points within one week were determined using a multiparameteric analyzer. Serum levels of high-mobility group box 1(HMGB1), tumor necrosis factor(TNF)-α, interleukin(IL)-1β, IL-6, and IL-10 as well as nuclear factor(NF)-κB activity were determined by enzyme-linked immunosorbent assay. Hepatic morphological changes at 36 h after ALF induction were assessed by hematoxylin and eosin staining. Expression of PKC-δ in liver tissue and peripheral blood mononuclear cells(PBMCs) was analyzed by Western blot.RESULTS: The expression and activation of PKC-δ were up-regulated in liver tissue and PBMCs of mice with D-Gal N/LPS-induced ALF. Inhibition of PKC-δ activation with rottlerin significantly increased the survival rates and decreased serum ALT/AST levels at 6, 12 and 24 h compared with the control group(P < 0.001). Rottlerin treatment also significantly decreased serum levels of HMGB1 at 6, 12, and 24 h, TNF-α, IL-6 and IL-1 β at 12 h compared with the control group(P < 0.01). The inflammatory cell infiltration and necrosis in liver tissue were also decreased in the rottlerin treatment group. Furthermore, sphingosine kinase 1(Sph K1) dependent PKC-δ activation played an important role in promoting NF-κB activation and inflammatory cytokine production in ALF.CONCLUSION: Sph K1 dependent PKC-δ activation plays an important role in promoting NF-κB activation and inflammatory response in ALF, and inhibition of PKC-δ activation might be a potential therapeutic strategy for this disease.

Enhanced proton irradiation resistance in Cs-doped CH_(3)NH_(3)PbI_(3) films and solar cells

Mixed-cation perovskite solar cells have attracted tremendous attention in space applications due to their excellent power conversion efficiency (PCE) and stability to light and heat.Although the evolution of photovoltaic performance in different space environments has been investigated,the role of inorganic cesium ions (Cs^(+)) in the enhancement of irradiation resistance needs to be further clarified.Herein,the structure and performance evolution of Cs-doped CH_(3)NH_(3)PbI_(3)(MAPbI_(3)) films and planar heterojunction devices under proton irradiation up to 1×10^(16)p cm^(-2) were studied.5%of Cs^(+) doping can increase the cohesive energy of MAPbI_(3)and effectively alleviate the lattice strain induced by proton irradiation,thereby enhancing the crystallinity and stability of films.The bandgap changes of irradiated Cs_(0.05)MA_(0.95)PbI_(3) films under the identical fluence were only one third of that of MAPbI_(3) films.Upon irradiation under the fluence of 1×10^(14)p cm^(-2),the density of trap states in the undoped and 5%Cs-doped films increased by 71%and 9%,respectively,and the average PCE of 20 corresponding devices decreased only by 12%and 9%,respectively.This proves that the replacement of organic methylamine ion with inorganic cesium ion contributes to the improvement of MAPbI_(3) resistance to proton irradiation,thus confirming the application prospects of mixed-cation or all-inorganic perovskite solar cells in spacecraft.

鼻咽癌的調強放射治療

目的探討調強放射治療鼻咽癌的近期療效及治療倂發症。方法從2003年10月至2006年2月間,本院放射治療中心收治了111例初程治療,無遠處轉移的鼻咽癌病例,全部採用調強放射治療,腫瘤劑量爲70Gy/30次,預防劑量爲54~60Gy/30次。其中有72例鼻咽原發灶加量4~15Gy(中位値9.4),40例接受了同期放化療治療。結果隨訪率100%,中位隨訪時間爲23.8個月(9~37個月),2年無局部區域進展生存率,無遠處轉移生存率、無疾病進展生存率和總生存率分別爲97.4%-83.1%,82.2%和90.2%。治療後大部份病人沒有或祇有輕度的皮膚和黏膜副反應(0~1級),一年以上的病人沒有或祇有輕度口乾症狀的佔85.9%,中度口乾症狀爲14.1%。結論鼻咽癌採用調強放射治療,提高了腫瘤局部控制率和生存,同時減少了正常組織損傷。

Multidisciplinary and multiscale nanoscience research roadmap based on large scientific facilities

With the advancement of modern science and technology, large scientific facilities are increasingly oriented toward demand and application, and can be used for basic research as well as serving multiple disciplines. Developing large scientific facilities and related analytical technologies enhances understanding of large scientific facilities and popularizes their application in research across multiple disciplines. The combination of light or neutron sources from large scientific facilities and advanced analytical technologies can be achieved for materials structure information, dynamics study of chemical reactions, high dissociation of biomolecules, 3D visualization of energy materials or biological samples, etc. We first introduce the progress of domestic large scientific facilities of synchrotron radiation(SR) and free electron lasers(FELs) with different wavelengths and neutron sources.We further discuss the comparison between Chinese and typical foreign facilities in X-ray radiation from X-ray tubes, synchrotrons, X-ray FELs, and neutron sources based on physical parameters of light and neutron sources. In addition, we focus on the technological progress and perspectives combined with advanced X-ray radiation and neutron sources of large scientific facilities in China, especially in the nanoscience fields of energy catalysis and biological science. We hope that this roadmap will provide references on technology and methods to experimental users, as well as prospects for future development of technologies based on large research infrastructure facilities. Comprehensive studies and guidelines for basic research to practical application in various disciplines can be made with the assistance of large scientific facilities.

基于先进紫外光源的生物质谱技术的最新进展及展望

生物大分子质谱是研究复杂生命体系中分子的序列组成、动态结构、相互作用和空间分布的前沿科学领域.先进紫外光源特别是同步辐射、自由电子激光等大科学装置的发展,为光解离-串联质谱和光电离-质谱成像等生物大分子质谱研究尖端技术的进步提供了新的机遇.本综述中,我们总结了不同波长先进光源包括X射线、极紫外激光等在蛋白质、脂质等生物分子高效光解离和序列、结构、相互作用表征,光化学氧化标记和动态结构分析,高效光电离和高灵敏度质谱检测及空间分布成像等领域的研究进展;进一步展望了新一代先进紫外光源特别是具有更高亮度、更短脉冲、更高重频的极紫外自由电子激光在生物大分子质谱研究中的应用前景和可能带来的技术突破.

A female in vivo haploid-induction system via mutagenesis of egg cell-specific peptidases

Crop breeding schemes can be significantly accelerated by using(doubled)haploid plants.In vivo haploid induction has been applied in plant breeding for decades but is still not available for all crops and genotypes,and haploidization rates are generally very low.Therefore,methodological improvements to and new concepts for haploidization are required.Here,we report a novel system for the induction of haploid plants by mutating genes encoding egg cell-specific aspartic endopeptidases(ECSs).We show that after successful sperm–egg cell fusion,ECSs play a critical role to ensure male and female nucleus fusion after fertilization.The ecs1 ecs2 double mutant can induce haploids by both selfing and hybridization in Arabidopsis and ECS mutation is also capable of producing haploids in rice.In summary,our study develops a novel approach for maternal haploidization and provides new insights into the molecular basis of fertilization.

驾驶舱眩光仿真分析与实车评价

良好的汽车驾驶舱视觉舒适性能够保障驾乘人员的行车安全,提高道路交通的稳定性,因此汽车驾驶舱的人机工程布置和内饰设计需要考虑减少驾驶舱眩光的产生。针对该问题,提出了一种基于CATIA/SPEOS的汽车驾驶室眩光评估方法。利用光线追踪法分析产生光反射部件之间的几何位置关系,在考虑材质属性、外界环境、真实光学效果和阳光照射方向的前提下,利用视觉仿真精确映射汽车驾驶舱的眩光位置。以某型SUV驾驶舱为例,通过光线跟踪分析发现,组合仪表不会有光线的直接照射产生眩光,中控大屏幕会有通过天窗和右边侧窗玻璃的光线直接照射产生眩光;通过视觉仿真分析发现,组合仪表由于光线折反射导致轻微眩光,中控大屏幕眩光面积较大;前挡风玻璃区域在中午和下午眩光较为严重,左边外后视镜区域在下午有空调镀铬装饰和风口造型的成像;中控大屏幕贴合AR防眩光膜优化后,分析结果表明,整块屏幕视觉效果趋于一致,视觉功效有显著提高。通过制定驾驶舱炫目主观评价流程并进行主观评价分析,得出驾驶舱眩光主观评价分析结果与仿真方法评估结果一致,表明该评估方法在新车研发和车型改款试制前期对驾驶室眩光分析和优化具有可行性。