“精密测量物理”重大研究计划结题综述

国家自然科学基金“精密测量物理”重大研究计划于2013年立项,执行期限为2014年1月至2021年12月,国家自然科学基金委员会于2023年3月对“精密测量物理”重大研究计划进行了结束评估,评估结果为“优秀”。本文介绍了“精密测量物理”重大研究计划的立项背景、总体科学目标、总体布局、实施思路及总体完成情况,并概述了该领域下一步发展的建议。

Aspartoacylase suppresses prostate cancer progression by blocking LYN activation

Background:Globally,despite prostate cancer(PCa)representing second most prevalent malignancy in male,the precise molecular mechanisms implicated in its pathogenesis remain unclear.Consequently,elucidating the key molecular regulators that govern disease progression could substantially contribute to the establishment of novel therapeutic strategies,ultimately advancing the management of PCa.Methods:A total of 49 PCa tissues and 43 adjacent normal tissues were collected from January 2017 to December 2021 at Zhongnan Hospital of Wuhan University.The advanced transcriptomic methodologies were employed to identify differentially expressed mRNAs in PCa.The expression of aspartoacylase(ASPA)in PCa was thoroughly evaluated using quantitative real-time PCR and Western blotting techniques.To elucidate the inhibitory role of ASPA in PCa cell proliferation and metastasis,a comprehensive set of in vitro and in vivo assays were conducted,including orthotopic and tumor-bearing mouse models(n=8 for each group).A combination of experimental approaches,such as Western blotting,luciferase assays,immunoprecipitation assays,mass spectrometry,glutathione S-transferase pulldown experiments,and rescue studies,were employed to investigate the underlying molecular mechanisms of ASPA's action in PCa.The Student‘s t-test was employed to assess the statistical significance between two distinct groups,while one-way analysis of variance was utilized for comparisons involving more than two groups.A two-sided P<0.05 was deemed to indicate statistical significance.Results:ASPA was identified as a novel inhibitor of PCa progression.The expression of ASPA was found to be significantly down-regulated in PCa tissue samples,and its decreased expression was independently associated with patients’prognosis(HR=0.60,95%CI 0.40–0.92,P=0.018).Our experiments demonstrated that modulation of ASPA activity,either through gain-or loss-of-function,led to the suppression or enhancement of PCa cell proliferation,migration,and invasion,respectively.The inhibitory role of ASPA in PCa was further confirmed using orthotopic and tumor-bearing mouse models.Mechanistically,ASPA was shown to directly interact with the LYN and inhibit the phosphorylation of LYN as well as its downstream targets,JNK1/2 and C-Jun,in both PCa cells and mouse models,in an enzyme-independent manner.Importantly,the inhibition of LYN activation by bafetinib abrogated the promoting effect of ASPA knockdown on PCa progression in both in vitro and in vivo models.Moreover,we observed an inverse relationship between ASPA expression and LYN activity in clinical PCa samples,suggesting a potential regulatory role of ASPA in modulating LYN signaling.Conclusions:Our findings provide novel insights into the tumor-suppressive function of ASPA in PCa and highlight its potential as a prognostic biomarker and therapeutic target for the management of this malignancy.

Endoplasmic reticulum stress improved chicken tenderness,promoted apoptosis and autophagy during postmortem ageing

In this study,endoplasmic reticulum(ER)stress inducer tunicamycin(TM)and inhibitor 4-phenylbutyric acid(4-PBA)were used to treat postmortem chicken breast muscle to investigate changes in tenderness and effects on apoptosis and autophagy during 5 days ageing.TM-induced ER stress reduced shear force,enhanced myofibril fragmentation index(MFI),disrupted myofibril structure,increased desmin degradation,and activatedμ-calpain and caspase-12.In addition,TM-induced ER stress increased the expression of Bax,Bim,and cytochrome c,and decreased the expression of Bcl-x L.Furthermore,TM-induced ER stress improved the conversion of LC3I to LC3II,raised the expression of Beclin-1,and decreased the expression of p62,PI3K,and m TOR.The opposite results were observed after 4-PBA treatment.These results suggested that ER stress could improve chicken tenderness,promote apoptosis and autophagy during chicken postmortem ageing.

Protective mechanism of quercetin compounds against acrylamide-induced hepatotoxicity

Quercetin compounds have antioxidant,anti-inflammatory and anticancer pharmacological functions.Longterm exposure to acrylamide(AA)can cause liver injury and endanger human health.However,whether quercetin compounds can attenuate AA-induced liver injury and the specific mechanism are not clear.Here,we studied the mechanism and structure-activity relationship of quercetin compounds in reducing AA-induced hepatotoxicity in vivo and in vitro.In vivo studies found that quercetin-like compounds protect against AAinduced liver injury by reducing oxidative stress levels,activating the Akt/m TOR signaling pathway to attenuate autophagy,and improving mitochondrial apoptosis and endoplasmic reticulum stress-mediated apoptosis.In vitro studies found that quercetin compounds protected Hep G2 cells from AA by attenuating the activation of AA-induced autophagy,lowering reactive oxygen species(ROS)levels by exerting antioxidant effects and thus attenuating oxidative stress,increasing mitochondrial membrane potential(MMP),and improving apoptosis-related proteins,thus attenuating AA-induced apoptosis.Furthermore,the conformational differences between quercetin compounds correlated with their protective capacity against AA-induced hepatotoxicity,with quercetin showing the best protective capacity due to its strongest antioxidant activity.In conclusion,quercetin compounds can protect against AA-induced liver injury through multiple pathways of oxidative stress,autophagy and apoptosis,and their protective capacity correlates with antioxidant activity.

Spin gap in quasi-one-dimensional S=3/2 antiferromagnet CoTi2O5

Quasi-one-dimensional(1D)antiferromagnets are known to display intriguing phenomena especially when there is a spin gap in their spin-excitation spectra.Here we demonstrate that a spin gap exists in the quasi-1D Heisenberg antiferromagnet CoTi2O5 with highly ordered Co2+/Ti4+occupation,in which the Co2+ions with S=3/2 form a 1D spin chain along the a-axis.CoTi2O5 undergoes an antiferromagnetic transition at TN~24 K and exhibits obvious anisotropic magnetic susceptibility even in the paramagnetic region.Although a gapless magnetic ground state is usually expected in a quasi-1D Heisenberg antiferromagnet with half-integer spins,by analyzing the specific heat,the thermal conductivity,and the spin-lattice relaxation rate(1/T1)as a function of temperature,we found that a spin gap is opened in the spin-excitation spectrum of CoTi2O5 around TN,manifested by the rapid decrease of magnetic specific heat to zero,the double-peak characteristic in thermal conductivity,and the exponential decay of 1/T1 below TN.Both the magnetic measurements and the first-principles calculations results indicate that there is spin-orbit coupling in CoTi2O5,which induces the magnetic anisotropy in CoTi2O5,and then opens the spin gap at low temperature.

Distal margin distance in radical resection of locally advanced rectal cancer after neoadjuvant therapy

Colorectal cancer has a high incidence and mortality rate in China, with the majority of cases being middle and low rectal cancer. Surgical intervention is currently the main treatment modality for locally advanced rectal cancer, with the common goal of improving oncological outcomes while preserving function. The controversy regarding the circumferential resection margin distance in rectal cancer surgery has been resolved. With the promotion of neoadjuvant therapy concepts and advancements in technology, treatment strategies have become more diverse.Following tumor downstaging, there is an increasing trend towards extending the safe distance of distal rectal margin. This provides more opportunities for patients with low rectal cancer to preserve their anal function.However, there is currently no consensus on the specific distance of distal resection margin.

Progress in research on the exploration and evaluation of deep geothermal resources in the Fujian-Guangdong-Hainan region,China

Deep geothermal resources in the Fujian-Guangdong-Hainan region,China,offer significant potential for sustainable energy.The diverse igneous rock formations along the southeast coast present intricate geological challenges that impede exploration and evaluation efforts.In this study,we address critical concerns related to the Fujian-Guangdong-Hainan region's deep geothermal resources,encompassing heat source composition,formation conditions,strategic favorable areas,and exploration directions.Our methods involve the analysis of regional geothermal reservoirs and cap rocks.Major findings include:the primary heat sources in the Fujian-Guangdong-Hainan region consist of the radioactive heat generation from granites in the crust,heat conduction in the mantle,and,in specific areas like Yangjiang and Shantou,melts within the middle and lower crust;the deep,high-temperature geothermal resources in the region predominantly reside in basins'depressed areas.These areas are characterized by the confluence of triple heat sources:heat from the Earth's crust,mantle,and other supplementary sources;our analysis led to the identification of three strategic areas favorable for deep geothermal resources in the Fujian-Guangdong-Hainan region.These are the Beibu Gulf Basin's continental area,the Yuezhong Depression,and the Fuzhou-Zhangzhou area.

富氧空位的非晶氧化铜高选择性电催化还原CO_(2)制乙烯

过量化石能源的消耗导致大气中的二氧化碳含量不断上升,由此引发包括温室效应在内的环境问题。对此,常温常压下的电催化二氧化碳还原手段为制备高附加值的化工原料和实现碳循环提供了一种很有前景的技术储备。在众多的二氧化碳还原产物中,碳氢化合物尤其是乙烯,它作为塑料和其他化工产品的重要原料受到广泛的关注。电催化二氧化碳还原制乙烯工艺不仅可适配于现有的生产设备也可作为取代目前工业化的裂解方法。近年来,研究者们为了开发高效的电催化二氧化碳还原制乙烯催化剂开展了大量的研究。不过值得注意的是,大部分研究集中于铜基材料。尽管目前研究者取得了很多成果,但仍缺少可高选择性产乙烯的二氧化碳还原催化剂。如何设计出可活化二氧化碳分子,同时对*CO和*COH中间物有强吸附能力的催化剂是研究难点。针对此问题,本文中通过真空蒸镀的方法制备出一种富氧空位的非晶氧化铜纳米薄膜催化剂。受益于纳米薄膜的构建和氧空位的引入,该催化剂可快速进行电荷和物质的交换,并利于二氧化碳分子的吸附及优化还原中间产物的亲和力,进而表现出优异的电催化二氧化碳制乙烯的性能。结果表明,在加有0.1 mol·L^(−1)碳酸氢钾溶液的H型电解池中测试中,该催化剂在相对于可逆氢电极电势为−1.3 V的产乙烯法拉第效率可达85%±3%。此外,该催化剂在长达48 h的电催化还原过程中仍可保持高的乙烯选择性。这些指标与已报道的最好的铜基催化剂的性能相当。另外,结构和化学手段表明该催化剂在电解反应中可保持良好的稳定性。进一步,我们测试了该催化剂在膜电极体系的性能,结果表明该催化剂的最大乙烯局部电流密度可达115.4 mA·cm^(−2)(操作电压为−1.95 V),最高法拉第效率可达78%±2%(操作电压为−1.75 V)。理论和实验结果证明该催化剂的高乙烯选择性源于引入的氧空位不仅有利于二氧化碳分子的吸附,而且可增强对*CO和*COH的亲和力。本论文的研究不仅可激发学术界对高乙烯选择性的非晶铜基材料开发,同时在一定程度上提供有关电催化二氧化碳制乙烯的反应机制认识。

Advances on Axial Coordination Design of Single‑Atom Catalysts for Energy Electrocatalysis:A Review

Single-atom catalysts(SACs)have garnered increasingly growing attention in renewable energy scenarios,especially in electrocatalysis due to their unique high efficiency of atom utilization and flexible electronic structure adjustability.The intensive efforts towards the rational design and synthesis of SACs with versatile local configurations have significantly accelerated the development of efficient and sustainable electrocatalysts for a wide range of electrochemical applications.As an emergent coordination avenue,intentionally breaking the planar symmetry of SACs by adding ligands in the axial direction of metal single atoms offers a novel approach for the tuning of both geometric and electronic structures,thereby enhancing electrocatalytic performance at active sites.In this review,we briefly outline the burgeoning research topic of axially coordinated SACs and provide a comprehensive summary of the recent advances in their synthetic strategies and electrocatalytic applications.Besides,the challenges and outlooks in this research field have also been emphasized.The present review provides an in-depth and comprehensive understanding of the axial coordination design of SACs,which could bring new perspectives and solutions for fine regulation of the electronic structures of SACs catering to high-performing energy electrocatalysis.

An integrated and efficient process for borax preparation and magnetite recovery from soda-ash roasted ludwigite ore under CO–CO_(2)–N_(2) atmosphere

To realize the comprehensive utilization of ludwigite ore,an integrated and efficient route for the boron and iron separation was proposed in this work,which via soda-ash roasting under CO–CO_(2)–N_(2) atmosphere followed by grind-leaching,magnetic separation,and CO_(2) carbonation.The effects of roasting temperature,roasting time,CO/(CO+CO_(2))composition,and Na_(2)CO_(3) dosage on the boron and iron separation indices were primarily investigated.Under the optimized conditions of the roasting temperature of 850℃,roasting time of 60 min,soda ash dosage of 20 wt%,and CO/(CO+CO_(2)) of 10 vol%,92%of boron was leached during wet grinding,and 88.6%of iron was recovered during the magnetic separation and magnetic concentrate with a total iron content of 61.51 wt%.Raman spectra and^(11)B NMR results indicated that boron exists asB(OH)_(4)^(-) in the leachate,from which high-purity borax pentahydrate could be prepared by CO_(2) carbonation.

Identification of multiple risk factors for colorectal cancer relapse after laparoscopic radical resection

BACKGROUND Colorectal cancer(CRC)is a common life-threatening disease that often requires surgical intervention,such as laparoscopic radical resection.However,despite successful surgeries,some patients experience disease relapse.Identifying the risk factors for CRC relapse can help guide clinical interventions and improve patient outcomes.AIM To determine the risk factors that may lead to CRC relapse after laparoscopic radical resection.METHODS We performed a retrospective analysis using the baseline data of 140 patients with CRC admitted to our hospital between January 2018 and January 2020.All included participants were followed up until death or for 3 years.The baseline data and laboratory indicators were compared between the patients who experienced relapse and those who did not experienced relapse.RESULTS Among the 140 patients with CRC,30 experienced relapse within 3 years after laparoscopic radical resection and 110 did not experience relapse.The relapse group had a higher frequency of rectal tumors with low differentiation and lymphatic vessel invasion than that of the non-relapse group.The expression of serum markers and the prognostic nutritional index were lower,whereas the neutrophil-to-lymphocyte ratio,expression of cytokeratin 19 fragment antigen 21-1,vascular endothelial growth factor,and Chitinase-3-like protein 1 were significantly higher in the relapse group than those in the non-relapse group.The groups did not differ significantly based on other parameters.Logistic regression analysis revealed that all the above significantly altered factors were independent risk factors for CRC relapse.CONCLUSION We identified multiple risk factors for CRC relapse following surgery,which can be considered for the clinical monitoring of patients to reduce disease recurrence and improve patient survival.

Distribution,exploitation,and utilization of intermediate-to-deep geothermal resources in eastern China

The part of China,east of the Hu Huanyong Line,is commonly referred to as eastern China.It is characterized by a high population density and a well-developed economy;it also has huge energy demands.This study assesses and promotes the large-scale development of geothermal resources in eastern China by analyzing deep geological structures,geothermal regimes,and typical geothermal systems.These analyses are based on data collected from geotectology,deep geophysics,geothermics,structural geology,and petrology.Determining the distribution patterns of intermediate-to-deep geothermal resources in the region helps develop prospects for their exploitation and utilization.Eastern China hosts superimposed layers of rocks from three major,global tectonic domainsd namely Paleo-Asian,Circum-Pacific,and Tethyan rocks.The structure of its crust and mantle exhibits a special flyover pattern,with basins and mountains as well as well-spaced uplifts and depressions alternatively on top.The lithosphere in Northeast China and North China is characterized by a thin,low density crust and mantle,whereas the lithosphere in South China has a thin,low density crust and a thick,high density mantle.The middle and upper crust contain geobodies with high conductivity and low velocity,with varying degrees of development that create favorable conditions for the formation and enrichment of geothermal resources.Moderate-to-high temperature geothermal resources are distributed in the MesozoiceCenozoic basins in eastern China,although moderate temperature geothermal resources with low abundance dominate.Porous sandstone reservoirs,karstified fractured-vuggy carbonate reservoirs,and fissured granite reservoirs are the main types of geothermal reservoirs in this region.Under the currently available technical conditions,the exploitation and utilization of geothermal resources in eastern China favor direct utilization over large-scale geothermal power generation.In Northeast China and North China,geothermal resources could be applied for large-scale geothermal heating purposes;geothermal heating could be applied during winter along parts of the Yangtze River while geothermal cooling would be more suitable for summer there;geothermal cooling could also be applied to much of South China.Geothermal resources can also be applied to high value-added industries,to aid agricultural practices,and for tourism.

Relationship between radiogenic heat production in granitic rocks and emplacement age

Granites play a crucial role in the Earth's thermal regime and its evolution.Radiogenic heat production(RHP)by the decay of radioactive elements(U,Th,K)in granites is a significant parameter in estimating the thermal structure of the lithosphere.RHP variability of granites with their emplacement ages could provide insights for thermal modeling in different geological epochs.An aggregated RHP from 2877 globally-distributed granitic samples of continental crust are analyzed for this study;these sample cover the entire geological history.The average bulk RHP in all types of granitic rocks of all ages is 2.92±1.86μW/m^(3).The RHP tends to increase gradually with progressively younger geologic emplacement age,based on a statistical analysis of the data.However,the youngest granites do not necessarily have the highest RHP.The mean RHP in 181 representative Cenozoic Himalayan leucogranitesdwhich are the youngest granites found on Earth,is as low as 1.84μW/m^(3).This is probably related to the initial conditions of magma formation,magmatic source material,and differentiation processes in the HimalayaneTibetan plateau.By correcting the decay factor,variations of the RHP in the emplaced granitic rocks are obtained,indicating the changing levels of heat production and different thermal regimes on Earth in various geological epochs.The highest RHP in granitic rocks emplaced in the Archean and Early Proterozoic corresponds to two global-scale collisional events during supercontinent cycles,at 2.7 and 1.9 Ga respectively.RHPs of granites can be an important indicator in the study of Earth's thermal regime and its evolution.

The LXRB-SREBP1 network regulates lipogenic homeostasis by controlling the synthesis of polyunsaturated fatty acids in goat mammary epithelial cells

Background:In rodents,research has revealed a role of liver X receptors(LXR) in controlling lipid homeostasis and regulating the synthesis of polyunsaturated fatty acids(PUFA).Recent data suggest that LXRB is the predominant LXR subtype in ruminant mammary cells,but its role in lipid metabolism is unknown.It was hypothesized that LXRB plays a role in lipid homeostasis via altering the synthesis of PUFA in the ruminant mammary gland.We used overexpression and knockdown of LXRB in goat primary mammary epithelial cells(GMEC) to evaluate abundance of lipogenic enzymes,fatty acid profiles,content of lipid stores and activity of the stearoyl-Co A desaturase(SCD1) promoter.Results:Overexpression of LXRB markedly upregulated the protein abundance of LXRB while incubation with si RNA targeting LXRB markedly decreased abundance of LXRB protein.Overexpression of LXRB plus T0901317(T09,a ligand for LXR) dramatically upregulated SCD1 and elongation of very long chain fatty acid-like fatty acid elongases 5–7(ELOVL 5–7),which are related to PUFA synthesis.Compared with the control,cells overexpressing LXRB and stimulated with T09 had greater concentrations of C16:0,16:1,18:1n7,18:1n9 and C18:2 as well as desaturation and elongation indices of C16:0.Furthermore,LXRB-overexpressing cells incubated with T09 had greater levels of triacylglycerol and cholesterol.Knockdown of LXRB in cells incubated with T09 led to downregulation of genes encoding elongases and desaturases.Knockdown of LXRB attenuated the increase in triacylglycerol and cholesterol that was induced by T09.In cells treated with dimethylsulfoxide,knockdown of LXRB increased the concentration of C16:0 at the expense of C18:0,while a significant decrease in C18:2 was observed in cells incubated with both si LXRB and T09.The abundance of sterol regulatory element binding transcription factor 1 precursor(p SREBP1) and its mature fragment(n SREBP1) was upregulated by T09,but not LXRB overexpression.In the cells cultured with T09,knockdown of LXRB downregulated the abundance for p SREBP1 and n SREBP1.Luciferase reporter assays revealed that the activities of wild type SCD1 promoter or fragment with SREBP1 response element(SRE) mutation were decreased markedly when LXRB was knocked down.Activity of the SCD1 promoter that was induced by T09 was blocked when the SRE mutation was introduced.Conclusion:The current study provides evidence of a physiological link between the LXRB and SREBP1 in the ruminant mammary cell.An important role was revealed for the LXRB-SREBP1 network in the synthesis of PUFA via the regulation of genes encoding elongases and desaturases.Thus,targeting this network might elicit broad effects on lipid homeostasis in ruminant mammary gland.

Overexpression of a sugarcane ScCaM gene negatively regulates salinity and drought stress responses in transgenic Arabidopsis thaliana

Calmodulin(CaM)proteins play a key role in signal transduction under various stresses.In the present study,the effects of a sugarcane ScCaM gene(NCBI accession number:GQ246454)on drought and salt stress tolerance in transgenic Arabidopsis thaliana and Escherichia coli cells were evaluated.The results demonstrated a significant negative role of ScCaM in the drought and salt stress tolerance of transgenic lines of A.thaliana,as indicated by the phenotypes.In addition,the expression of AtP5CS and AtRD29A,two genes tightly related to stress resistance,was significantly lower in the overexpression lines than in the wild type.The growth of E.coli BL21 cells expressing ScCaM showed weaker tolerance under mannitol and NaCl stress.Taken together,this study revealed that the ScCaM gene plays a negative regulatory role in both mannitol and NaCl stresses,and it possibly exerts protective mechanisms common in both prokaryotes and eukaryotes under stress conditions.

Research on Multi-Blockchain Electronic Archives Sharing Model

The purpose of introducing blockchain into electronic archives sharing and utilization is to break the information barrier between electronic archives sharing departments by relying on technologies such as smart contract and asymmetric encryption.Aiming at the problem of dynamic permission management in common access control methods,a new access control method based on smart contract under blockchain is proposed,which improves the intelligence level under blockchain technology.Firstly,the Internet attribute access control model based on smart contract is established.For the dynamic access of heterogeneous devices,the management contract,permission judgment contract and access control contract are designed;Secondly,the access object credit evaluation algorithm based on particle swarm optimization radial basis function(PSO-RBF)neural network is used to dynamically generate the access node credit threshold combined with the access policy,so as to realize the intelligent access right management method.Finally,combined with the abovemodels and algorithms,the workflow of electronic archives sharing and utilization model of multi blockchain is constructed.The experimental results show that the timeconsuming of the process increases linearly with the number of continuous access to electronic archives blocks,and the secure access control of sharing and utilization is feasible,secure and effective.

藏族功能障碍者接受辅助器具服务的真实体验

目的了解西藏自治区藏族功能障碍者在接受辅助器具服务过程中的真实体验,为服务质量改善和政策制定提供参考。方法采用半结构式个人访谈收集资料。于2021年9-12月以目的抽样法在拉萨市选取代表3类不同经济水平地区的10名藏族功能障碍者参与研究。采用Colaizzi七步法进行资料分析。结果结果呈现了3个主题和7个子主题:认同辅助器具带来的切实益处(提升功能障碍者自理能力;协助家庭成员照护工作,促进家庭关系和谐);面临的问题及负担(专业服务获取困难且流程繁琐;不会正确使用;心理负担:害怕跌倒和污名化);需求及期望(提供社会支持,降低使用成本;提升基层无障碍设施可及性,改善辅助器具使用环境)。结论正视藏族功能障碍者在接受辅助器具服务过程中面临的问题及挑战,关注功能障碍群体的真实体验,提出有针对性地改善和优化用户体验的建议,可为未来干预研究及相关政策制定提供参考及依据。

The parallel biosynthesis routes of hyperoside from naringenin in Hypericum monogynum

Hyperoside is a bioactive flavonoid galactoside in both medicinal and edible plants.It plays an important physiological role in the growth of flower buds.However,the hyperoside biosynthesis pathway has not been systematically elucidated in plants,including its original source,Hypericaceae.Our group found abundant hyperoside in the flower buds of Hypericum monogynum,and we sequenced its transcriptome to study the biosynthetic mechanism of hyperoside.After gene screening and functional verification,four kinds of key enzymes were identified.Specifically,HmF3Hs(flavanone 3-hydroxylases)and HmFLSs(flavonol synthases)could catalyze flavanones into dihydroflavonols,as well as catalyzing dihydroflavonols into flavonols.HmFLSs could also convert flavanones into flavonols and flavones with varying efficiencies.HmF3′H(flavonoid 3′-hydroxylase)was found to act broadly on 4′-hydroxyl flavonoids to produce 3′,4′-diydroxylated flavanones,dihydroflavonols,flavonols,and flavones.HmGAT(flavonoid 3-O-galactosyltransferase)would transform flavonols into the corresponding 3-O-galactosides,including hyperoside.The parallel hyperoside biosynthesis routes were thus depicted,one of which was successfully reconstructed in Escherichia coli BL21(DE3)by feeding naringenin,resulting in a hyperoside yield of 25 mg/l.Overall,this research not only helped us understand the interior catalytic mechanism of hyperoside in H.monogynum concerning flower development and bioactivity,but also provided valuable insights into these enzyme families.

Cl^(-)ions accelerating interface charge transfer in a Si/In_(2)S_(3) Faradaic junction photocathode for solar seawater splitting

Photoelectrocatalytic seawater splitting is a promising low-cost method to produce green hydrogen in a large scale.The effects of Cl^(-)ions in seawater on the performance of a photoanode have been reported in previous studies.However,few researches have been done on the roles of Cl^(-)ions in a photocathode.Herein,for the first time,we find that Cl^(-)ions in the electrolyte improve the photocurrent of a Si/In_(2)S_(3) photocathode by 50% at-0.6 V_(RHE).An in-situ X-ray photoelectron spectroscopy(XPS)characterization combined with the time-of-flight secondary-ion mass spectrometry by simulating photoelectrochemical conditions was used to investigate the interface charge transfer mechanism.The results suggest that there is an In_(2)^(+3)S_(3-x)(OH)_(2x)layer on the surface of In_(2)S_(3) in the phosphate buffer solution(PBS)electrolyte,which plays a role as an interface charge transfer mediator in the Si/In_(2)S_(3) photocathode.The In_(2)^(+3)S_(3-x)(OH)_(2x)surface layer becomes In_(2)^(+3)S_(3-x)(Cl)_(2x)in the PBS electrolyte with NaCl and accelerates the charge transfer rate at the In_(2)S_(3)/electrolyte interface.These results offer a new concept of regulating interface charge transfer mediator to enhance the performance of photoelectrocatalytic seawater splitting for hydrogen production.

学龄前早产儿近视的屈光参数研究

目的:研究1~6岁早产儿近视患者屈光参数的变化,探讨早产儿近视发生发展与屈光参数的关系。方法:收集2016-01/2018-12在湖南省儿童医院眼科门诊随诊的1~6岁早产儿近视者158例316眼作为早产儿近视组,选取同期随诊的早产儿非近视者164例328眼作为早产儿非近视组。检测并分析两组受检者角膜曲率(CR)、前房深度(ACD)、玻璃体腔深度(VITR)、眼轴长度(AL)、晶状体厚度(LT)等屈光参数。结果:1~3岁受检者中,早产儿近视组较早产儿非近视组CR陡(44.47±1.14D vs 43.38±1.22D),AL延长(21.89±0.71mm vs 21.24±0.56mm)(均P<0.05),而ACD、VITR及LT值无明显差异(均P>0.05);4~6岁受检者中,早产儿近视组较早产儿非近视组AL延长(22.49±1.32mm vs21.43±0.72mm,P<0.05),而CR、ACD、VITR及AT值无明显差异(均P>0.05)。1~3岁早产儿高度近视患者较低、中度近视患者CR陡、AL长,4~6岁早产儿高度近视患者较低、中度近视患者VITR深、AL长。结论:屈光参数发育不匹配可能是早产儿近视发生的原因之一,其中眼轴长度变化起主要作用,而角膜曲率陡是低龄(≤3岁)早产儿近视发展的重要因素之一。