The Effect of Antisite Disorder and Particle Size on Li Intercalation Kinetics in Monoclinic LiMnBO3

In materials containing 1D lithium diffusion channels, cation disorder can strongly affect lithium intercalation processes. This work presents a model to explain the unusual transport properties of monoclinic LiMnBO₃, a material determined by scanning electron microscopy and synchrotron X‐ray diffraction to contain a wide particle size distribution and Mn/Li antisite disorder. First‐principles calculations indicate that Mn occupying Li sites obstruct the 1D lithium diffusion channel along the [001] direction. While channel blockage by the antisites significantly lowers Li mobility in large particles, Li kinetics in small particles and particle surfaces are found to be less sensitive to the presence of antisite disorder. Thus, in an electrode containing a large particle size distribution, smaller particles have higher Li mobility, and the measured Li diffusivity as determined by potentiostatic intermittent titration test varies as a function of particle size. The Li capacity in monoclinic LiMnBO₃ is kinetically controlled by the fraction of large particles with antisite disorder, but is not intrinsically limited. These results strongly suggest that particle nanosizing will significantly enhance the electrochemical performance of LiMnBO₃.     

海南野生稻资源调查收集与保护

为了加强海南野生稻资源的保护和研究利用,2002—2013年对海南省18市(县)野生稻资源进行野外调查、资源收集和原、异位保护。初步查明,目前在全省15个市(县)发现154个野生稻自然居群,其中普通野生稻136个、疣粒野生稻11个、药用野生稻7个。收集到野生稻居群87个,其中普通野生稻80个、疣粒野生稻4个、药用野生稻3个,总共2900余份野生稻种茎,经繁殖和编目后妥善保存于海南省农业科学院试验基地的热带野生稻异位保存圃中,并参照农业行业标准-农业野生植物原生境保护点建设技术规范,分别在文昌、琼海、儋州、万宁、陵水和保亭等县(市)建立了6个野生稻原生境保护点,其中普通野生稻4个,疣粒野生稻1个,药用野生稻1个。根据调查结果,对海南野生稻濒危状况及其根源进行了分析,提出了海南野生稻保护相关建议。     

星形胶质细胞通过CX47促进少突胶质前体细胞增殖

目的:研究星形胶质细胞(AST)对少突胶质前体细胞(OPC)生长分化的影响及作用机制。方法:用P3SD乳鼠,建立星形胶质细胞与少突胶质前体细胞原代培养体系。实验分两部分,第一部分为常规OPC培养组、AST分泌因子组、AST与OPC直接接触式培养组;第二部分为AST与OPC直接接触式培养组、缝隙连接干扰对照组、缝隙连接干扰组。免疫荧光鉴定OPC与AST细胞纯度,光镜观察细胞生长状态,流式细胞术检测细胞周期,转录组测序分析不同状态下OPC中缝隙连接蛋白CX47差异表达,PCR和Western blot检测鉴定转录组测序CX47差异表达,EDU检测CX47干扰后OPC增殖能力,流式细胞术测干扰CX47后细胞周期变化。结果:光镜与流式检测发现,与AST接触培养的OPC增殖能力最强、新生细胞数目最多。转录组测序分析和PCR验证显示,AST接触调控OPC增殖的主要差异表达蛋白为CX47,干扰CX47后细胞周期阻滞在G1期,OPC增殖能力明显下降。结论;AST可通过缝隙连接蛋白CX47调控细胞周期,促进OPC增殖。     

食用菌超细粉免疫调节和抗氧化功能研究

以糙皮侧耳、双孢蘑菇、金针菇、3个黑木耳品种、3个香菇品种为材料,通过测定小鼠体重、免疫器官重量、细胞免疫功能、体液免疫功能、单核-巨噬细胞的吞噬功能、血清及肝脏中谷胱甘肽过氧化物酶、超氧化物歧化酶、肝脏中白介素-6、丙二醛等指标进行小鼠免疫功能的评价研究。结果表明:"四川青川"香菇、"北神奇1号"黑木耳和"黑龙江黑29"黑木耳能显著增强小鼠的细胞免疫功能;糙皮侧耳、"辽宁恒仁"香菇、金针菇、"北神奇1号"黑木耳、"黑龙江黑29"黑木耳均能显著促进小鼠单核吞噬细胞的吞噬能力,增强小鼠机体的免疫力;糙皮侧耳、"四川青川"香菇、"辽宁恒仁"香菇、金针菇和"黑龙江黑29"黑木耳具有提高小鼠肝脏中白介素-6含量的作用;双孢蘑菇、"福建古田"香菇、"辽宁恒仁"香菇、金针菇增加小鼠血清溶血素水平,具有显著的特异性体液免疫增强作用。此外,双孢蘑菇、金针菇、"北神奇1号"黑木耳、"吉林黑29"黑木耳均可显著提高血清和肝脏中的GSH-PX活性;糙皮侧耳能提高小鼠血清中和肝脏中SOD活性;从而达到清除自由基和抗氧化损伤的作用。综合上述结果,9种食用菌超细粉均具有显著增强小鼠免疫调节能力和抗氧化作用,为食用菌功能食品产品开发利用提供支撑。     

Mutation of Oryza sativa CORONATINE INSENSITIVE 1b (OsCOI1b) delays leaf senescence

Jasmonic acid (JA) functions in plant development, including senescence and immunity. Arabidopsis thaliana CORONATINE INSENSITIVE 1 encodes a JA receptor and functions in the JA‐responsive signaling pathway. The Arabidopsis genome harbors a single COI gene, but the rice (Oryza sativa) genome harbors three COI homologs, OsCOI1a, OsCOI1b, and OsCOI2. Thus, it remains unclear whether each OsCOI has distinct, additive, synergistic, or redundant functions in development. Here, we use the oscoi1b‐1 knockout mutants to show that OsCOI1b mainly affects leaf senescence under senescence‐promoting conditions. oscoi1b‐1 mutants stayed green during dark‐induced and natural senescence, with substantial retention of chlorophylls and photosynthetic capacity. Furthermore, several senescence‐associated genes were downregulated in oscoi1b‐1 mutants, including homologs of Arabidopsis thaliana ETHYLENE INSENSITIVE 3 and ORESARA 1, important regulators of leaf senescence. These results suggest that crosstalk between JA signaling and ethylene signaling affects leaf senescence. The Arabidopsis coi1‐1 plants containing 35S:OsCOI1a or 35S:OsCOI1b rescued the delayed leaf senescence during dark incubation, suggesting that both OsCOI1a and OsCOI1b are required for promoting leaf senescence in rice. oscoi1b‐1 mutants showed significant decreases in spikelet fertility and grain weight, leading to severe reduction of grain yield, indicating that OsCOI1‐mediated JA signaling affects spikelet fertility and grain filling.     

复杂性眼外伤患者玻璃体切割围手术期护理体会

目的:玻璃体切割术是眼科手术中比较复杂精细显手术,主要应用于治疗眼外伤导致的玻璃体出血,玻璃体浑浊,复杂性视网膜脱离以及增殖性玻璃体视网膜病变。本文主要探讨玻璃体切割术治疗复杂性眼外伤患者的围手术期护理的临床效应。方法:总结作者所在科室多年来护理眼外伤患者的临床经验,对2013年3月至2013年7月入院的75例(75只眼)复杂性眼外伤患者进行悉心的术前心理护理,完善的用药指导,充分的术前准备,术后特殊卧位的指导,预防并发症的护理及出院指导。结果:术后视力提高57例(76.0%),视力不变13(17.3%)例,视力下降5例(6.7%),28例眼内异物患者均经手术顺利取出异物。相关手术并发症经医护人员的对症治疗后均得到有效控制。患者术后满意度达98%以上,医生满意度达100%。结论:复杂性眼外伤患者玻璃体切割手术围手术期进行全方位的护理服务,对促进病人康复起到至关重要的作用。