The advantages of multi-level omics research on stem cell-based therapies for ischemic stroke

Stem cell transplantation is a potential therapeutic strategy for ischemic stroke. However, despite many years of preclinical research, the application of stem cells is still limited to the clinical trial stage. Although stem cell therapy can be highly beneficial in promoting functional recovery, the precise mechanisms of action that are responsible for this effect have yet to be fully elucidated. Omics analysis provides us with a new perspective to investigate the physiological mechanisms and multiple functions of stem cells in ischemic stroke. Transcriptomic, proteomic, and metabolomic analyses have become important tools for discovering biomarkers and analyzing molecular changes under pathological conditions. Omics analysis could help us to identify new pathways mediated by stem cells for the treatment of ischemic stroke via stem cell therapy, thereby facilitating the translation of stem cell therapies into clinical use. In this review, we summarize the pathophysiology of ischemic stroke and discuss recent progress in the development of stem cell therapies for the treatment of ischemic stroke by applying multi-level omics. We also discuss changes in RNAs, proteins, and metabolites in the cerebral tissues and body fluids under stroke conditions and following stem cell treatment, and summarize the regulatory factors that play a key role in stem cell therapy. The exploration of stem cell therapy at the molecular level will facilitate the clinical application of stem cells and provide new treatment possibilities for the complete recovery of neurological function in patients with ischemic stroke.

Chalcogen heteroatoms doped nickel-nitrogen-carbon single-atom catalysts with asymmetric coordination for efficient electrochemical CO_(2) reduction

The electronic configuration of central metal atoms in single-atom catalysts(SACs)is pivotal in electrochemical CO_(2) reduction reaction(eCO_(2)RR).Herein,chalcogen heteroatoms(e.g.,S,Se,and Te)were incorporated into the symmetric nickel-nitrogen-carbon(Ni-N_(4)-C)configuration to obtain Ni-X-N_(3)-C(X:S,Se,and Te)SACs with asymmetric coordination presented for central Ni atoms.Among these obtained Ni-X-N_(3)-C(X:S,Se,and Te)SACs,Ni-Se-N_(3)-C exhibited superior eCO_(2)RR activity,with CO selectivity reaching~98% at-0.70 V versus reversible hydrogen electrode(RHE).The Zn-CO_(2) battery integrated with Ni-Se-N_(3)-C as cathode and Zn foil as anode achieved a peak power density of 1.82 mW cm^(-2) and maintained remarkable rechargeable stability over 20 h.In-situ spectral investigations and theoretical calculations demonstrated that the chalcogen heteroatoms doped into the Ni-N_(4)-C configuration would break coordination symmetry and trigger charge redistribution,and then regulate the intermediate behaviors and thermodynamic reaction pathways for eCO_(2)RR.Especially,for Ni-Se-N_(3)-C,the introduced Se atoms could significantly raise the d-band center of central Ni atoms and thus remarkably lower the energy barrier for the rate-determining step of ^(*)COOH formation,contributing to the promising eCO_(2)RR performance for high selectivity CO production by competing with hydrogen evolution reaction.

CT引导下125I粒子植入术对晚期肺癌及肺转移癌的治疗作用

背景与目的原发性肺癌及肺转移癌均为常见肺部恶性肿瘤,是主要的癌症相关死亡原因。晚期肺癌及肺转移癌以全身治疗为主,局部治疗对全身治疗后肺部残存的顽固性病灶或复发病灶为一种有效治疗手段。125I放射性粒子植入作为一种高效的适形放疗,对肺部局限性癌灶具有一定的控制作用。本研究旨在探讨计算机断层扫描(computed tomography,CT)引导下经皮穿刺肺组织间125 I放射性粒子植入治疗晚期肺癌和肺转移癌的临床效果及安全性。方法连续性收集2014年1月1日-2018年11月30日浙江大学医学院附属第一医院胸外科行125 I放射性粒子植入术治疗的105例晚期肺癌和肺转移癌患者的临床病理资料,术后随访至2019年3月。观察粒子植入术的临床疗效及并发症发生情况。结果本研究共纳入105例患者,晚期肺癌患者78例,肺转移癌患者27例。粒子治疗患者术后中位生存时间为395天,术后1年生存率约为78.1%,术后2年生存率约为56.1%。粒子植入治疗晚期肺癌的效果与肺转移癌的效果相当。粒子联合射频消融、微波消融、化疗并没有提高粒子治疗效果。但是粒子联合外放射治疗较单纯粒子治疗具有显著生存劣势。结论CT引导下125 I放射性粒子植入术并发症可控,可以作为晚期肺癌和肺转移癌的一种安全有效的治疗方法。

农村地区父亲参与现状及其与幼儿发展的关系

父亲参与对儿童发展的重要性受到越来越多的关注,为考察当前我国农村地区父亲参与现状,探究父亲参与和幼儿发展的关系,本研究以620名农村幼儿及其家长作为调查对象,使用自编问卷从父亲是否缺位、父亲参与时间以及父亲参与活动内容等方面测查农村地区父亲参与状况,运用Achenbach儿童行为量表(CBCL)及相关测试评定幼儿行为、社会性、情绪、认知、动作发展水平,结果发现当前我国农村地区父亲参与现状不容乐观,缺位现象普遍且严重;父亲参与可以显著预测幼儿社交退缩、抑郁、注意力发展水平,父亲参与越积极,幼儿社交退缩越少、抑郁情绪越少、注意力发展越好。农村地区父亲应加强自身参与意识,农村家庭应积极支持父亲参与并提高参与质量,政府在发挥正确引导作用的同时应鼓励社会组织助力父亲参与。

非金属掺杂石墨相氮化碳光催化的研究进展与展望

自从Fujishima和Honda利用TiO2光阳极和Pt电极成功实现太阳能光电化学分解水之后,光催化被认为是解决环境污染和能源短缺两大问题最有前景的方法之一,因为该技术可以有效的利用太阳能这种地球上最丰富的能源来驱动多种不同的催化反应实现能源生产和环境净化,比如:水分解、CO2还原、有机污染物降解和有机合成等。除了金属氧化物、金属硫化物和金属氮氧化物等多类金属化合物半导体光催化剂,近几年,石墨相氮化碳(g-C3N4)因其原料来源广泛、无毒、稳定以及相对较窄的带隙(2.7 eV)而具备可见光响应等特点,在光催化领域获得了广泛的重视。然而,gC3N4对太阳光谱中可见光的吸收效率较低且光生电子和空穴复合严重,导致其光催化活性处于较低水平。至今,研究人员已经开发出多种提高g-C3N4光催化活性的方法,如元素掺杂、微纳结构和异质结构设计和助催化剂修饰等。元素掺杂被证明是调节g-C3N4独特电子结构和分子结构的有效方法,可以大幅扩展其光响应范围,并促进光生电荷分离。特别地是,非金属元素掺杂以提高g-C3N4的光催化活性已经得到很好的研究。通常用于掺杂g-C3N4的非金属元素是氧(O)、磷(P)、硫(S)、硼(B)、卤素(F、Cl、Br、I)和其他非金属元素(如碳(C)和氮(N)自掺杂),因为这些非金属元素有着易于获取的原材料并可以较为简单的引入g-C3N4骨架结构中。在这篇综述文章中,作者首先介绍了g-C3N4的结构和光学性质,接着简要介绍了光催化剂的g-C3N4的改性;然后详细回顾了非金属掺杂改善g-C3N4光催化活性的进展,同时总结了光催化机理以期更好地理解光催化的本质并指导新型g-C3N4光催化剂的开发。最后,对g-C3N4光催化剂的后续研究进行了展望。

Electron-Deficient Zn-N_(6) Configuration Enabling Polymeric Carbon Nitride for Visible-Light Photocatalytic Overall Water Splitting

Despite of suitable band structures for harvesting solar light and driving water redox reactions,polymeric carbon nitride(PCN)has suffered from poor charge transfer ability and sluggish surface reaction kinetics,which limit its photocatalytic activity for water splitting.Herein,atomically dispersed Zn-coordinated three-dimensional(3D)sponge-like PCN(Zn-PCN)is synthesized through a novel intermediate coordination strategy.Advanced characterizations and theoretical calculations well evidence that Zn single atoms are coordinated and stabilized on PCN in the form of Zn-N_(6) configura-tion featured with an electron-deficient state.Such an electronic configuration has been demonstrated contributive to promoted electron excitation,accelerated charge separation and transfer as well as reduced water redox barriers.Further benefited from the abundant surface active sites derived from the 3D porous structure,Zn-PCN realizes visible-light photocatalysis for overall water splitting with H_(2) and O_(2) simultaneously evolved at a stoichiometric ratio of 2:1.This work brings new insights into the design of novel single-atom photocatalysts by deepening the understanding of electronic configurations and reactive sites favorable to excellent photocatalysis for water splitting and related solar energy conversion reactions.

Heteroatom-doped porous carbon from methyl orange dye wastewater for oxygen reduction

Banana peel-derived porous carbon(BPPC) was prepared from banana peel and used as an adsorbent for methyl orange(MO) wastewater removal. BPPC-MO50 is a N,S-doped BPPC obtained via secondary carbonization. The BPPC-MO50 exhibited a high specific surface area of1774.3 m^2/g. Heteroatom-doped porous carbon(PC) was successfully synthesized from the BPPC absorbed MO at high temperature and used for oxygen reduction. The BPPC-MO50 displayed the highest ORR onset potential among all carbon-based electrocatalysts, i.e., 0.93 V vs.reversible hydrogen electrode(RHE). This is the first report to describe porous carbon-activated materials from agriculture and forestry waste that is used for adsorption of dyes from wastewater via an enhanced heteroatom(N,S) content. These results may contribute to the sustainable development of dye wastewater treatment by transforming saturated PC into an effective material and has potential applications in fuel cells or as energy sources.

利用三元合金保护和催化的硅光阳极与廉价硅太阳能电池相结合实现12.0%的太阳能制氢效率

n型硅(n-Si)表面在水溶液中容易被氧化和钝化,导致其在光电化学(PEC)分解水的析氧反应(OER)动力学缓慢。本工作通过欠电位沉积成功地在p^(+)n-Si基底上电沉积了三金属Ni_(0.9)Fe_(0.05)Co_(0.05)保护层。制备的Ni_(0.9)Fe_(0.05)Co_(0.05)/p^(+)n-Si光阳极具有优异的稳定性和PEC水氧化活性,具有相对低的OER起始电位(相对于可逆氢电极电势(RHE)仅为0.938 V),并且在1.23 V vs.RHE电位时具有较高的光电流密度(33.1 m A·cm^(-2)),显著优于Ni/p^(+)n-Si光阳极。工作证明了Fe在Ni层的掺杂会在Ni_(0.9)Fe_(0.05)Co_(0.05)/p^(+)n-Si界面处产生较大的能带弯曲,促进界面电荷分离。此外,Co的加入会产生丰富的Ni^(3+)和氧空位(Ov),作为活性位点可以加速OER动力学过程,协同促进PEC过程中的水氧化的活性。令人鼓舞的是,通过将Ni_(0.9)Fe_(0.05)Co_(0.05)/p^(+)n-Si光阳极连接到廉价的硅太阳能电池上,所制备的集成光伏/PEC(PV/PEC)器件实现了无偏压下高达12.0%的太阳制氢能量转换效率。这项工作提供了一种简单的方法来设计高效、稳定的n-Si基光阳极,并对其构效关系有了深刻的理解;这种方法制备的材料在集成低成本PV/PEC器件用于无辅助太阳能驱动水分解方面具有巨大的潜力。

Bio-Inspired Gelatin-Based Adhesive Modified with Waterborne Polyurethane on Click Chemistry

As a non-toxic,highly reactive biomass material,gelatin is wildly used as the component of biomass-based adhesive.However,like most aqueous adhesives,gelatin-based adhesives suffer from long solidifying time or high solidifying temperature due to the low volatility of water,which highly limits the application potential of gelatinbased adhesives.Inspired by the fast adhesion of marine organisms through the formation of chemical crosslinks,herein,a kind of low temperature curable eco-friendly gelatin-based adhesive with good adhesive properties and fast curing at low temperature is developed by introducing clicking chemical Diels-Alder(DA)reaction between blocked waterborne polyurethane(MWPU)and gelatin.The furfuryl glycidyl ether(FGE)and 4-Maleimidophenol(4-HPM)for the DA reaction are grafted on gelatin,and the end-capping of MWPU,respectively.With the addition of MWPU and FGE,the cross-linking degree of gelatin increased,and the adhesion properties of the adhesive were improved.The shear strength and T-peel strength of the modified adhesive reached 0.95 MPa and 1.42 N/mm,respectively,after the curing time of 8 min at 40℃,which can meet the application requirements as adhesive for bio-medical use.

Sporophytic control of tapetal development and pollen fertility by a mitogen-activated protein kinase cascade in rice

Tapetum,the innermost layer of the anther wall,provides essential nutrients and materials for pollen development.Timely degradation of anther tapetal cells is a prerequisite for normal pollen development in flowering plants.Tapetal cells facilitate male gametogenesis by providing cellular contents after highly coordinated programmed cell death(PCD).Tapetal development is regulated by a transcriptional network.However,the signaling pathway(s)involved in this process are poorly understood.In this study,we report that a mitogen-activated protein kinase(MAPK)cascade composed of OsYDA1/OsYDA2-OsMKK4-OsMPK6 plays an important role in tapetal development and male gametophyte fertility.Loss of function of this MAPK cascade leads to anther indehiscence,enlarged tapetum,and aborted pollen grains.Tapetal cells in osmkk4 and osmpk6 mutants exhibit an increased presence of lipid body-like structures within the cytoplasm,which is accompanied by a delayed occurrence of PCD.Expression of a constitutively active version of OsMPK6(CA-OsMPK6)can rescue the pollen defects in osmkk4 mutants,confirming that OsMPK6 functions downstream of OsMKK4 in this pathway.Genetic crosses also demonstrated that the MAPK cascade sporophyticly regulates pollen development.Our study reveals a novel function of rice MAPK cascade in plant male reproductive biology.

Enhancing performance and longevity of solid-state zinc-iodine batteries with fluorine-rich solid electrolyte interphase

Rechargeable zinc-iodine(ZnI_(2))batteries have gained popularity within the realm of aqueous batteries due to their inherent advantages,including natural abundance,intrinsic safety,and high theoretical capacity.However,challenges persist in their practical applications,notably battery swelling and vulnerability in aqueous electrolytes,primarily linked to the hydrogen evolution reaction and zinc dendrite growth.To address these challenges,this study presents an innovative approach by designing a solid-state ZnI_(2)battery featuring a solid perfluoropolyether based polymer electrolyte.The results demonstrate the formation of a solid electrolyte interphase layer on zinc,promoting horizontal zinc growth,mitigating dendrite penetration,and enhancing battery cycle life.Moreover,the solid electrolyte hinders the iodine ion shuttle effect,reducing zinc foil corrosion.Symmetric batteries employing this electrolyte demonstrate excellent cycle performance,maintaining stability for approximately 5000 h at room temperature,while solid-state ZnI_(2)batteries exhibit over 7000 cycles with a capacity retention exceeding 72.2%.This work offers a promising pathway to achieving reliable energy storage in solid-state ZnI_(2)batteries and introduces innovative concepts for flexible and wearable zinc batteries.

The Sequential Pricing of Ride-Hailing System with Rental Service in the Context of Fleet Electrification

Surging demand and reduced capacity in the ride-hailing industry have prompted numerous ride-hailing platforms to build their own car-rental services catering to drivers who do not possess private vehicles. However, the trade-off between the ride-hailing service and the car-rental service is an important issue that is still unclear in theory. Moreover, ride-hailing platforms are transitioning towards all-electric fleets in the context of Carbon Neutrality goals and government regulations. This paper considers a ride-hailing system comprising a monopolist ride-hailing platform, an electric vehicle (EV) rental firm, and a gasoline vehicle (GV) rental firm. Furthermore, we build a stylized model to study the sequential pricing of the system. The equilibrium outcomes show the significant impact of the ride-hailing platform’s decision to continue or withdraw offering EV rental services on EV and GV drivers’ net earnings, rental prices, and wages. The ride-hailing platform providing EV rental services increases EV drivers’ net earnings but decreases the GV driver wages and rental prices. However, the EV rental service offered by the ride-hailing platform does not necessarily lead to an increased total profit for the system. The improved profitability of the system by the ride-hailing platform providing EV rental services is contingent upon lower rider prices and higher fuel costs. The ride-hailing platform’s EV rental services provision also effectively fosters the ride-hailing fleet’s electrification. Furthermore, as the number of riders increases, the ride-hailing platform should reduce the commission rate for EV drivers to maintain competitiveness and profitability.

Polyacrylate modified Cu electrode for selective electrochemical CO_(2) reduction towards multicarbon products

Highly selective production of value-added multicarbon(C^(2+))products via electrochemical CO_(2) reduction reaction(eCO_(2)RR)on polycrystalline copper(Cu)remains challenging.Herein,the facile surface modification using poly(α-ethyl cyanoacrylate)(PECA)is presented to greatly enhance the C^(2+)selectivity for eCO_(2)RR over polycrystalline Cu,with Faradaic efficiency(FE)towards C^(2+)products increased from30.1%for the Cu electrode to 72.6%for the obtained Cu-PECA electrode at-1.1 V vs.reversible hydrogen electrode(RHE).Given the well-determined FEs towards C^(2+)products,the partial current densities for C^(2+)production could be estimated to be-145.4 mA cm~(-2)for the Cu-PECA electrode at-0.9 V vs.RHE in a homemade flow cell.In-situ spectral characterizations and theoretical calculations reveal that PECA featured with electron-accepting-C≡N and-COOR groups decorated onto the Cu electrode could inhibit the adsorption of^(*)H intermediates and stabilize the^(*)CO intermediates,given the redistributed interfacial electron density and the raised energy level of d-band center(E_(d))of Cu active sites,thus facilitating the C-C coupling and then the C^(2+)selective production.This study is believed to be guidable to the modification of electrocatalysts and electrodes with polymers to steer the surface adsorption behaviors of reaction intermediates to realize practical eCO_(2)RR towards value-added C^(2+)products with high activity and selectivity.

Epidemiology and genetic characterization of tet(X4)-positive Klebsiella pneumoniae and Klebsiella quasipneumoniae isolated from raw meat in Chengdu City, China

The rapid spread of mobile tigecycline resistance presents a significant public health threat,particularly with the increasing prevalence of tet(X4)-positive Enterobacterales across various species.This study aimed to inves-tigate the epidemic features and transmission dynamics of tet(X4)-positive Klebsiella pneumoniae(K.pneumo-niae)through the analysis of 206 raw meats,including pork(n=182),beef(n=16),duck(n=5),and chicken(n=3).These samples were collected from schools,markets,and restaurants in Chengdu City,China.A total of 25 isolates were obtained from 13 administrative regions.All isolates exhibited resistance to tetracycline,tigecycline,ampicillin,chloramphenicol,and florfenicol.Over half of the isolates also demon-strated resistance to streptomycin(80%),sulfamethoxazole/trimethoprim(72%),ciprofloxacin(64%),and ampicillin/sulbactam(56%).Among these strains,14 distinct sequence types(STs)were identified,revealing evidence of inter-regional clonal spread,notably among 9 K.pneumoniae ST3393.Phylogenetic analysis revealed the presence of two K.pneumoniae ST5 closely resembling hypervirulent K.pneumoniae from Jiangsu.Importantly,12 isolates were capable of transferring tigecycline resistance to Escherichia coli J53.Further plasmid analysis showed that the tet(X4)-harboring plasmids in K.pneumoniae could be classified into four types,primarily belonging to the IncFIA(HI1)/HI1A/HI1B hybrid plasmid(n=16)and IncFII plasmid(n=7),which significantly contributed to the cross-species dissemination of tet(X4).In summary,this study highlights the prevalence of MDR tet(X4)-positive K.pneumoniae in Chengdu,driven predominantly by clonal expansion and plasmid-mediated horizontal gene transfer.These findings emphasize the importance of contin-uous surveillance of tet(X4)-positive K.pneumoniae in raw meat and the implementation of effective measures to control their spread.

中国苏铁属植物资源和保护

苏铁类植物含2科10属,是现存种子植物最原始的类群之一,具有重要的科学研究和保护价值。苏铁属(Cycas)是唯一在中国有自然分布的苏铁类植物,约20种,多数种类为中国特有。中国的苏铁属植物主要分布于西南地区和东南沿海,大部分种类为狭域分布的类群,其生存繁衍受到了严重的威胁,均被列为国家一级重点保护野生植物。基于文献资料收集整理和野外调查,本文对中国苏铁属植物的研究和保护进行了阶段性总结。介绍了中国苏铁属植物分类研究、地理分布;阐述了中国苏铁植物生存面临的主要威胁及相应的保护措施,提出了保护方案的制定应遵循遗传学特征等科学依据。文中总结了我国苏铁植物保护科研工作中存在的5个主要问题:(1)苏铁植物基础科学问题有待进一步研究,(2)苏铁植物生境破坏较为严重,(3)人为盗采贩卖依然猖獗而苏铁植物园林园艺育种事业却举步不前,(4)苏铁自身生物学特性导致繁殖困难,(5)迁地保护难以保证苏铁种质“纯洁性”等,同时针对这些问题提出相应建议,以期为我国苏铁属植物的研究、保护以及可持续利用工作提供参考。

太行山华北豹袭击家畜的时空特点与管理建议:以山西省和顺县为例

人兽冲突是全球野生动物保护面临的共同挑战。袭击家畜是大型食肉动物引发人兽冲突的主要原因之一,如果管理不当还会导致针对大型食肉动物的报复性猎杀等严重威胁。冲突的缓解需要深入了解冲突发生的规律与原因,评估当地社区与居民的态度与看法,以采取因地制宜的管理措施。太行山是华北豹(Panthera pardus japonensis)的核心分布区,华北豹袭击家牛的问题是该区域野生华北豹保护中面临的一大挑战。本研究以山西省和顺县为研究区域,在多方联合发起的“和顺县华北豹袭击家牛肇事补偿项目”实施过程中,系统收集了2015–2019年期间华北豹袭击家畜事件的记录,结合同期的红外相机监测数据,探究了袭击事件的时空分布格局,并从生境和猎物的角度分析了背后的原因。本文还评估了豹肇事造成的经济损失,以及受损农户对华北豹的态度和对补偿的满意度。2015–2019年,项目区域内共记录到华北豹袭击家牛事件195起,向116户受损农户提供补偿资金共27.05万元。分析结果显示,华北豹袭击家牛事件在夏季最多,时间上与家牛上山散放的季节重叠;袭击风险随狍(Capreoluspygargus)相对多度的上升而下降,随家牛相对多度和距村庄距离的增加而上升,但保护区内外和华北豹相对多度对袭击风险的影响不显著。对107名受损农户的访谈结果显示,华北豹袭击家牛事件虽然对当地畜牧业所造成的整体损失较小,但对受损农户而言其家庭收入损失严重,因此导致受损农户对华北豹持负面态度,且认为现有的补偿金额偏低。基于本研究的结果,我们提出如下管理建议以期缓解未来该地区华北豹带来的人兽冲突:(1)加强放牧管理、改进管理方式,特别是限制牛群离开村庄的距离,以及在家牛散放期间将牛群每晚赶回牛圈以降低家畜被袭击的风险;(2)开展禁牧试点,严格划分允许放牧与禁止放牧的区域;(3)继续开展华北豹袭击家牛的定损与补偿工作,降低当地农户的经济损失,同时开展社区走访、自然教育,提升当地居民对华北豹的容忍度;(4)加强野生动物种群的监测与保护,促进人与野生动物的和谐共存。

中国云豹种群分布现状与关键栖息地信息更新

云豹(Neofelis nebulosa)是中国大型猫科动物中对森林生态系统依赖性最高的物种。中国作为云豹的主要分布区,由于长期以来缺乏深入研究和有效保护,在盗猎、森林采伐、土地利用变化等威胁因素的共同作用下,云豹在中国的分布范围和种群数量近数十年来均大幅缩减,其分布现状亟需全面评估。本研究系统检索和查阅了国内1950年以来的云豹标本、野外调查记录、地方志、新闻报道等直接证据,整理了中国各省级行政区内云豹记录存在的年代;基于2010–2020年国内55个地区的红外相机监测数据,结合同期研究文献中记录的中国云豹确认分布位点,校准了已发表的云豹栖息地适合度模型,并在此基础上叠加保护地和行政区划图层,根据2010–2020年间森林覆盖率的减量评估云豹栖息地适合度的变化,以识别我国的云豹关键栖息地和保护优先区。结果显示,1950–2009年,我国的云南、西藏、四川、陕西、甘肃、重庆、贵州、广西、广东、海南、湖北、湖南、安徽、江西、浙江、福建以及台湾共17个省级行政区有云豹分布,但其中12个迄今已超过20年无确凿记录,且目前仅在云南省和西藏自治区仍有云豹记录延续。当前我国大陆地区云豹潜在栖息地总面积64,093 km~2,分别位于9个连续的栖息地斑块中,其中3个为跨境斑块。2010–2020年间,我国境内共在5个自然保护区的10个样区记录到云豹,全部位于西藏东南部以及云南西部和南部的2个跨境栖息地斑块(即“喜马拉雅-横断山脉西侧-若开山脉”和“无量山南麓-安南山脉”)的边缘。2010–2020年间,这两个斑块在中国境内区域的年均森林覆盖率减量(0.84%)小于境外(1.57%)。从本研究的结果推断,中国目前确认分布的云豹种群极有可能维持在跨境分布的生境中,面临内部和跨境的双重挑战。相关保护地应有针对性地加强反盗猎执法,并开展栖息地恢复工作以提升云豹栖息地质量与斑块连通性,同时与周边分布区国家开展跨境保护合作,为现有云豹种群的长期生存和发展提供必要基础。

Repress,on of MYBL2 by Both microRNA858a and HY5 Leads to the Activation of Anthocyanin Biosynthetic Pathway in Arabidopsis

Extensive studies in various plants show that the anthocyanin biosynthetic process is affected by environmental factors and regulated by many transcription factors through sophisticated regulatory networks. However, it remains largely unclear about the roles of microRNA in this process. Here, we demonstrate that miR858a is a positive regulator of anthocyanin biosynthesis in Arabidopsis seedlings. Overexpression of miR858a enhances the accumulation of anthocyanins, whereas the reduced miR858a activity results in low levels of anthocyanins in STTM858 transgenic plants. We found that miR858a inhibits the expression of MYBL2, a key negative regulator of anthocyanin biosynthesis, by translational repression. In addition, ELONGATED HYPOCOTYL 5 （HYS） was shown to directly bind the MYBL2 promoter and represses its expression via specific histone modifications. Interestingly, we found that miR858a exhibits light- responsive expression in an HY5-dependent manner. Together, these results delineate the HY5- MIR858a-MYBL2 loop as a cellular mechanism for modulating anthocyanin biosynthesis, suggesting that integration of transcriptional and posttranscriptional regulation is critical for governing proper anthocyanin accumulation in response to light and other environmental factors.

Function-switchable metal/semiconductor junction enables efficient photocatalytic overall water splitting with selective water oxidation products

A novel metal/semiconductor photocatalyst,Cu nanoparticles(NPs)modified TiO2 hollow spheres(Cu/TiO2),was designed for efficient photocatalytic overall water splitting(POWS)under both ultraviolet(UV)and visible(Vis)light.This Cu/TiO2 photocatalyst possesses excellent POWS performance under Vis light at the highest level among the reported TiO2-based photocatalysts.Interestingly,the metal/semiconductor junction formed between Cu and TiO2 enables controlled water-oxidation product selectivity(H2O2 or O2)via different reaction pathways regulated by irradiation wavelengths.Under UV light,the electrons excited in TiO2 are captured by Cu NPs through the Cu/TiO2 Schottky interface for H2 production,with the photoholes in TiO2 producing H2O2 through a two-electron process;whilst under Vis light,Cu NPs act as plasmon to inject hot electrons to TiO2 for H2 production,while O2 is produced by hot holes on Cu NPs via a four-electron process.This rational design of function-switchable metal/semiconductor junction may be helpful to understand the mechanisms for POWS with desired gas/liquid water-oxidation products.

Boosting photocatalytic hydrogen production by creating isotype heterojunctions and single-atom active sites in highly-crystallized carbon nitride

Carbon nitride-based photocatalysts hold an enormous potential in producing hydrogen.A strategy to simultaneously create isotype heterojunctions and active sites in highly-crystallized carbon nitride is anticipated to significantly boost the photocatalytic activity,but is yet to be realized.Herein,we find that cobalt salt added in the ionothermal synthesis can promote the phase transition of heptazine-based crystalline carbon nitride(CCN)to triazine-based poly(triazine imide)(PTI),rendering the creation of singleatom cobalt coordinated isotype CCN/PTI heterojunction.Co-CCN/PTI exhibits an appreciable apparent quantum yield of 20.88%at 425 nm for photocatalytic hydrogen production with a rate achieving3538μmol h^(-1)g^(-1)(λ>420 nm),which is 4.8 times that of CCN and 27.6 times that of PTI.The high photocatalytic activity is attributed to the Type II isotype highly-crystallized CCN/PTI heterojunction for promoting charge carrier migration,and the single-atom Co sites for accelerating surface oxidation reaction.