水下亚波长广角声单向传输结构设计与优化

利用传递矩阵法,基于流固超晶格的单元传递矩阵,计算并分析了无限周期流固超晶格的能带结构以及有限周期级联超晶格的透射谱。在此基础上,耦合一维周期性矩形声栅与级联超晶格,构造了水下亚波长广角声单向传输结构,揭示了其广角声单向传输机制。有限元仿真结果表明,该结构能够实现约20°广角入射声波的单向传输效应,同时还具有宽频带、高整流比等特性。通过优化声栅单元的方位角,有效地提高了结构的正向导通率。本文结果突破了基于声子晶体的声单向传输设计中面临的"波长-尺寸"限制,有助于水下声整流器件朝着小型化和集成化方向发展。国家自然科学基金青年项目(11604128)水声技术重点实验室装备预研基

Effects of electro-acupuncture at stomach meridian acupoints on serum and urine metabolic profiles of gastric ulcer model rats

目的:采用核磁共振氢谱技术(1H NMR)研究电针胃经穴对胃溃疡模型大鼠血清和尿液代谢轮廓的影响。方法:40只SD大鼠随机分为空白组、模型组、胃经穴组和胆经穴组,每组10只。除空白组外,利用束缚冷应激法制备大鼠胃溃疡模型,造模成功后用电针分别刺激胃经组和胆经组相关穴位,收集大鼠的血清和尿液,获取一维1H NMR谱,并利用模式识别方法分析各组间的代谢轮廓差异。结果:与模型组比较,胃经穴组血清中的肌醇、甘氨酸、谷氨酰胺、异亮氨酸、缬氨酸和尿液中的肌酸酐、乳酸、醋酸盐、肌酸、琥珀酸盐、牛磺酸、甘氨酸、苯乙酰甘氨酸、尿囊素、胆碱、三甲胺、甲酸盐、甜菜碱代谢物的表达水平得到了明显地恢复(P<0.05),更接近空白组的代谢水平。结论:电针胃经穴可通过调节胃溃疡大鼠的氨基酸代谢和脂肪代谢促进胃黏膜损伤的修复。Objective: To explore the effects of electro-acupuncture at stomach meridian acupoints on serum and urine metabolic profiles of gastric ulcer model rats by application of 1H nuclear magnetic resonance(1H NMR) spectroscopy. Methods: Forty SD rats were randomly divided into the control group, model group, stomach meridian group and gallbladder meridian group, with 10 rats in each group. The gastric ulcer rat model was established by the restrained cold stress method. After modeling, the model rats were treated with electro-acupuncture at the stomach meridian and gallbladder meridian respectively, the serum and urine of rats were collected to obtain one dimensional 1H NMR spectrum, and the differences of metabolic profiles between these groups were analyzed by the pattern recognition method. Results: Compared to model group, the concentration of myo-inositol, glycine, glutamine, isoleucine, valine in serum from the stomach meridian group have obviously recovered and returning to normal level. The urinary metabolites such as Creatinine, lactic acid, acetic acid salt, acid, succinic acid salt, taurine, glycine, phenylacetyl glycine, allantoin, choline, trimethylamine, formate, betaine have also partly recovered after electro-acupuncture stimulation in the stomach meridian(P<0.05). Conclusion: Electro-acupuncture at stomach meridian acupoints could repair the gastric ulcer lesion by regulating the metabolism of lipid and amino acid in rats with gastric ulcer.国家自然科学基金项目(No.81473751,No.81260556);; 广东省自然科学基金项目(No.2014 A030313005);; 福建省自然科学基金项目(No.2015J05168);; 福建省卫生厅科研项目(No.wzpw201301)~

Development of a Two-dimensional Ultrasonic Vibration Assisted Grinding Technique of Monocrystal Silicon

基于超声振动磨削能有效提高加工效率及加工表面质量的特性,通过设计具有伸缩和弯曲两种模态的压电陶瓷椭圆振子,实现了单晶硅二维椭圆振动磨削技术。对超声振子的振动特性进行检测,证实改变压电陶瓷两电极之间的交流信号相位差和电压幅值,可得到不同形状和振幅的椭圆振动。对单晶硅进行超声磨削与普通磨削的对比试验,结果表明二维振动磨削的磨削力大幅降低,表面粗糙度显著减小,表面质量明显提高,加工表面延性域去除比例增加。从而证实二维超声振动磨削方法能够实现高效率高质量单晶硅加工。Based on the characteristics of higher machining efficiency and higher surface quality of ultrasonic vibration grinding,a two-dimensional ultrasonic vibration grinding of monocrystal silicon technique is achieved by designing elliptical vibrator with longitudinal mode and bending mode.The measurement results on the vibration characteristics of vibrator show that shape and amplitude of elliptical vibration can be modulated by changing voltage amplitude and phase difference between the piezoelectric ceramics electrodes.The grinding experimental results show that under the elliptic ultrasonic vibration assistance,grinding forces are reduced largely,the surface roughness is decreased significantly,the surface quality is improved obviously,and moreover the percentage of ductile-mode removal material increases.These indicate that high efficiency and high surface quality machining of monocrystal silicon can be achieved with elliptic vibration assisted grinding.国防科研资助项目(62301090103

SURVEY OF MIXED INFECTIONS OF FISH-BORNE TREMATODES IN PINYUAN COUNTY AND DNA(RAPD)ANALYSIS

目的　调查广东省平远县棘隙吸虫及其他鱼源性吸虫混合感染情况。方法　对鱼类宿主取鱼鳃和鱼肉等组织 ,镜检囊蚴 ;用水洗过筛沉淀法粪检虫卵 ,部分虫卵阳性动物解剖检查。采用DNA -RAPD技术 ,比较福建棘隙吸虫广东株与福建株。结果　查出华支睾吸虫 (Clonorchissinensis)、东方次睾吸虫 (Metorchisorientalis)、福建棘隙吸虫 (Echinochasmusfujianensis)、日本棘隙吸虫 (E japonicus)、抱茎棘隙吸虫 (E perfoliatus)和钩棘单睾吸虫 (Haplorchispumilio) 6种。第二中间宿主为麦穗鱼等 11种 ,感染率 48 3% (182 / 377) ,有 92 4%的阳性鱼混合感染 2种以上吸虫囊蚴。保虫宿主狗、猫感染率 79 2 % (19/ 2 4) ,每只阳性动物均有 2种以上吸虫混合感染。 15个引物在福建棘隙吸虫广东株与福建株两者共获DNA片段 185个 ,共享度 (F) =0 984,遗传距离 (D) =0 0 16。结论　当地为人兽共患的多种鱼源性吸虫混合感染区。形态学观察和分子生物学检测结果相印证 ,福建棘隙吸虫广东株与福建棘隙吸虫福建株为同一虫种。Aim To seek the possible existence of mixed infections of Echinochasmus fujianensis and other fish-borne tremtodes in Pinyuan county,Guangdong.Methods Metacercariae of trematodes were detected from gills,muscles and some other tissues of freshwater fish and examintd under microscopy Sedimentation pocedures were used to observe parasite ova in stool Adult worms were obtained from definitive animal hosts upon dissection Experimental animal infection were performed from metacercariae of E fujianensis strains in Fujian and Guangdong,and it's DNA analysis Random amplified Polymorphic DNA(RAPD).Results Six species of trematodes were found,including Clonorchis sinensis,Metorchis orientalis,E fujanensis, E japonicus,E perfoliatus and Haplorchis pumilio Eleven species of freshwater fish comprising Pseudorasbora parve were identified as the second intermediate hosts,with an average positive rate of 48 33%(182/377) The overall mixed infection animal were contracted with 2 or more species Dogs and cats were detected to be reservoir hosts,the total infection rate being 79 2%(19/24).92 4% of infecded fish were contracted with 2 or 6 speies of the metacercariae of trematodes 185 DNA fragments were obtained by 15 primers,F=0 894 and D=0 016 between E fujianensis Guandong and Fujian strain Conclusion There are six species of fish-borne trematodes which may cause infections in human and animal in the regions E fujianensis Guangdong stain and Fujian strain are the same species福建省科技计划基金!资助项目 (No 98-Z - 1 56);; 福建省“百千万人才”人选培养资

CDK5-dependent BAG3 degradation modulates synaptic protein turnover

阿尔茨海默病（AD）是严重威胁人类健康的重大神经系统疾病，AD的发生发展与衰老密切相关，目前临床治疗方法十分有限。因此迫切需要从AD致病早期入手，发现和鉴定导致AD神经功能紊乱的机制和靶点，为AD的早期防治提供基础。张杰教授及其团队从高通量磷酸化蛋白质组学入手，系统研究了CDK5在神经细胞中的磷酸化底物，鉴定出了在蛋白质量控制中发挥重要功能的BAG3蛋白是CDK5的全新底物。课题组从磷酸化蛋白质组学入手，发现和阐明了细胞周期蛋白激酶5（CDK5）通过调控BAG3在维持突触蛋白水平调控中的作用机制，及其在阿尔茨海默病（AD）发生发展中的机理。 该研究是多个团队历时8年合作完成的，香港中文大学的周熙文教授、美国匹兹堡大学的Karl Herrup教授、美国Sanford-Burnham研究所的许华曦教授、美国梅奥医学中心的卜国军教授，厦门大学医学院的文磊教授、张云武教授、赵颖俊教授、薛茂强教授，军事医学科学院的袁增强教授等都参与了该工作。 厦门大学医学院2012级博士生周杰超等为文章的第一作者，张杰教授为通讯作者。Background Synaptic protein dyshomeostasis and functional loss is an early invariant feature of Alzheimer’s disease (AD), yet the unifying etiological pathway remains largely unknown. Knowing that cyclin-dependent kinase 5 (CDK5) plays critical roles in synaptic formation and degeneration, its phosphorylation targets were re-examined in search for candidates with direct global impacts on synaptic protein dynamics, and the associated regulatory network was also analyzed. Methods Quantitative phospho-proteomics and bioinformatics analyses were performed to identify top-ranked candidates. A series of biochemical assays were used to investigate the associated regulatory signaling networks. Histological, electrochemical and behavioral assays were performed in conditional knockout, shRNA-mediated knockdown and AD-related mice models to evaluate its relevance to synaptic homeostasis and functions. Results Among candidates with known implications in synaptic modulations, BCL2-associated athanogene-3 (BAG3) ranked the highest. CDK5-mediated phosphorylation on Ser297/Ser291 (Mouse/Human) destabilized BAG3. Loss of BAG3 unleashed the selective protein degradative function of the HSP70 machinery. In neurons, this resulted in enhanced degradation of a number of glutamatergic synaptic proteins. Conditional neuronal knockout of Bag3 in vivo led to impairment of learning and memory functions. In human AD and related-mouse models, aberrant CDK5-mediated loss of BAG3 yielded similar effects on synaptic homeostasis. Detrimental effects of BAG3 loss on learning and memory functions were confirmed in these mice, and such were reversed by ectopic BAG3 re-expression. Conclusions Our results highlight that neuronal CDK5-BAG3-HSP70 signaling axis plays a critical role in modulating synaptic homeostasis. Dysregulation of the signaling pathway directly contributes to synaptic dysfunction and AD pathogenesis.This work was supported by the National Science Foundation in China (Grant: 31571055, 81522016, 81271421 to J.Z.; 81801337 to L.L; 81774377 and 81373999 to L.W.); Fundamental Research Funds for the Central Universities of China-Xiamen University (Grant: 20720150062, 20720180049 and 20720160075 to J.Z.); Fundamental Research Funds for Fujian Province University Leading Talents (Grant JAT170003 to L.L); Hong Kong Research Grants Council (HKUST12/CRF/13G, GRF660813, GRF16101315, AoE/M-05/12 to K.H.; GRF16103317, GRF16100718 and GRF16100219 to H.-M,C.); Offices of Provost, VPRG and Dean of Science, HKUST (VPRGO12SC02 to K.H.); Chinese University of Hong Kong (CUHK) Improvement on Competitiveness in Hiring New Faculty Funding Scheme (Ref. 133), CUHK Faculty Startup Fund and Alzheimer’s Association Research Fellowship (AARF-17-531566) to H.-M, C. 该研究受到了国家自然科学基金、厦门大学校长基金、福建省卫生教育联合攻关基金等的资助

类泛素蛋白及其中文命名

泛素家族包括泛素及类泛素蛋白,约20种成员蛋白.近年来,泛素家族领域取得了迅猛发展,并已与生物学及医学研究的各个领域相互交叉.泛素家族介导的蛋白质降解和细胞自噬机制的发现分别于2004和2016年获得诺贝尔奖.但是,类泛素蛋白并没有统一规范的中文译名. 2018年4月9日在苏州召开的《泛素家族介导的蛋白质降解和细胞自噬》专著的编委会上,部分作者讨论了类泛素蛋白的中文命名问题,并在随后的\"泛素家族、自噬与疾病\"(Ubiquitinfamily,autophagy anddiseases)苏州会议上提出了类泛素蛋白中文翻译草案,此草案在参加该会议的国内学者及海外华人学者间取得了高度共识.冷泉港亚洲\"泛素家族、自噬与疾病\"苏州会议是由美国冷泉港实验室主办、两年一度、面向全球的英文会议.该会议在海内外华人学者中具有广泛影响,因此,参会华人学者的意见具有一定的代表性.本文介绍了10个类别的类泛素蛋白的中文命名,系统总结了它们的结构特点,并比较了参与各种类泛素化修饰的酶和它们的生物学功能.文章由45名从事该领域研究的专家合作撰写,其中包括中国工程院院士1名,相关学者4名,长江学者3名,国家杰出青年科学基金获得者18名和美国知名高校华人教授4名.他们绝大多数是参加编写即将由科学出版社出版的专著《泛素家族介导的蛋白质降解和细胞自噬》的专家

Spatio-temporal Change and Simulation of Soil Organic Carbon in the Sangong River Watershed on the Northern Slope of Tianshan Mountains

土壤有机碳动态及其驱动机制是陆地生态系统碳循环与全球变化研究的热点问题之一。随着各国对《京都议定书》的重视，农业土壤碳库变化及其源/汇效应研究不断加强。近半个世纪以来，中国西北干旱区流域大规模开发活动改变了水土资源的时空分布，天然植被演变成人工植被，灌溉、施肥等人类耕作活动使得原始土壤逐步演变为绿洲耕作土壤，这些都使得绿洲土壤有机碳动态发生了显著变化。本文运用遥感和GIS技术、统计学与地统计学方法、生物地球化学模型等方法，以干旱区典型的三工河流域为例，估算流域土壤碳储量，分析绿洲土壤碳增汇的潜力，深入研究干旱区人为驱动的绿洲土壤有机碳变化及其驱动机制，并对未来可能的土地利用和管理情景下的土壤碳变化趋势进行了预测，这对推动干旱区土壤碳循环研究具有重要的科学意义。研究结论如下： （1）三工河流域土壤有机碳储量及时空分布：在0?-20cm的深度上，三工河流域土壤有机碳储量为1431.52×104 t，其中根据基于网格的土壤类型法计算的绿洲土壤有机碳储量为114.41×104 t C；绿洲阜北农场区域土壤有机碳具有显著的差异性，作物类型变化对土壤有机碳的影响显著，从1982、1999到2003年，土壤有机碳经历了先下降后上升的变化过程，其空间结构具有中等空间自相关，随着人类耕作时间的增长，土壤有机碳逐步得到提高。 （2）绿洲土壤碳增汇研究：阜北农场作物轮作和免耕/非免耕种植两种碳增汇方式对土壤有机碳的变化具有显著的影响。1982-1999年作物不同轮作方式的变化大多使得土壤有机碳含量下降，其中这一阶段棉花种植不利于土壤有机碳的积累，1999-2003年作物轮作方式变化使得土壤有机碳含量增加，其中其它作物向葡萄和啤酒花的转变使得土壤有机碳含量增幅明显；免耕/非免耕种植都可以有效增加土壤有机碳的储量，但免耕种植土壤有机碳积累效果明显强于非免耕种植。总之，阜北农场两种土壤碳增汇方式下，土壤有机碳随耕作时间总体呈增加的趋势。 （3）绿洲土壤有机碳变化模拟研究：CENTURY能够正确模拟干旱区绿洲土壤有机碳及其动态变化，在模拟达到平衡状态的1950年中，土壤活性有机碳周转速度较快，而土壤慢性有机碳累积速率具有明显的滞后性，土壤惰性有机碳性质非常稳定，其累积速率一直比较缓慢。由于土壤慢性有机碳的累积对SOC库的贡献最大，所以研究区SOC库增长速率与慢性有机碳累积速率基本一致。模型对阜北农场1951-2007年SOC及其组分变化的模拟研究表明，研究区自然状态被打破后的56年内，土壤有机碳先呈减小的趋势，之后迅速增加，并且超过原始自然状态下的土壤有机碳含量，土壤呈碳汇趋势。 （4）未来不同情景土壤有机碳变化预测：阜北农场PM1情景（两年棉花和十年多年生作物轮作）和PM2情景（连续种植多年生作物）下土壤SOC及其组分都呈明显的增加趋势，且变化趋势大致相似。总体来看，虽然两种情景土壤总有机碳都显示出了明显的 碳汇效应，但PM2情景土壤SOC呈持续而稳定的阶梯式增加趋势，而PM1情景增速相对弱于PM2，且其变异性较大。Study on soil organic carbon (SOC) dynamic and its driving mechanism is one of hot topics of terrestrial ecosystem carbon cycle and global change. With the attention to the Kyoto Protocol, the study on the agriculture SOC pool and its source or sink effect has been recognized more and more by scientists. In the past 50 years, the large-scale exploiture has resulted in the spatio-temporal distribution change of water and land resource in the north-west arid land of China. Some natural desert vegetation was replaced by anthropogenic vegetation or totally eliminated for settlement areas. Meantime, original soil has been gradually modified through irrigation and fertilization. All this human activities have resulted in the change of SOC storage. In this paper, the Sangong river watershed was taken as a study case, RS and GIS, statistics and geo-statistics, biogeochemical model method were combined to study on SOC pool dynamic and its driving mechanism. We estimated the SOC storage of Sangong river watershed, analyze the potential to sequester carbon in the oasis, and study on the SOC change driving by human activities, and predicted the SOC change trend under the land use and management scenarios. The main conclusions of this study were as follows: (1) SOC storage and its spatio-temporal distribution characteristic of the Sangong river watershed: The SOC storage is 1431.52×104 t C in the whole watershed, while it is only 114.41×104 t C in the oasis base on the grid method estimation. The crop types change significant affect the SOC change in the Fubei farm. The SOC tended to decline in the initial period, then increase in the late period from 1982 to 2003, and the spatial structure shows the spatial correlation belongs to moderate class. SOC had been increasing with the cultivation time. (2) Study on soil carbon sequestration in the oasis: The two patterns of soil carbon sequestration are crop rotation and till/no-till planting in the Fubei farm. The carbon sequestration patterns significant affect the SOC change. SOC tends to decrease due to the crop rotation change during 1982-1999, whereas the crop rotation change caused an increase of SOC during 1999-2003. The no-till and till planting can increase SOC, while the cumulation effect of SOC under the no-till planting is stronger than till planting. In conclusion, SOC trend to increase with the cultivation time under two soil carbon sequestration patterns. (3) Simulate the SOC change in the oasis: CENTURY model can precise simulation the SOC change. In the period for establishing equilibrium conditions (1950 years), the active SOC has a faster turnover time, while the turnover time and cumulation rate of the slow SOC was slow and sluggish. The passive SOC is very resistant to decomposition and have a slowness cumulation rate. The increase rate of total SOC and slow SOC is same due to the high proportion of slow SOC in the total SOC. The simulation results show SOC trend to increase during over 38 years since the natural vegetation land was reclaimed, and the oasis soil presented carbon sink. (4) Predict SOC change under the different land use and management scenarios: The prediction results show total SOC and three different carbon pools were increase under PM1 scenario ( two years cotton + ten years perennial crop rotation ) and PM2 scenario (continuous planting perennial crop ). The increase trend was same under two scenarios, while the SOC under PM2 scenario shows stable and durative ladder-way increase, the carbon sink effect is significant

天山北坡绿洲不同土地利用对土壤特性的影响

以天山北坡三工河流域冲积平原型绿洲作为研究区,选择12种土地利用系统作为土地利用方式的具体体现,通过采集不同土地利用系统上层土壤(0￣20cm)和下层土壤(20￣40cm)样方,分析不同土地利用系统对主要土壤特性的影响。研究结果表明:(1)土地利用系统对砂、粉砂和粘土粒度分布的影响显著。绿洲土壤砂含量随着土地种植年限增加有降低的趋势,而粉砂和粘土含量有增加的趋势;(2)绿洲土地利用系统对土壤pH值和养分变异的影响显著。人类强干扰的土地利用系统的土壤养分普遍高于人类影响较弱的土地利用系统,上层土壤养分普遍高于下层土壤,而且随着人类干扰时间的延长土壤养分呈整体增加趋势;(3)人类活动强干扰的土地利用系统土壤盐分含量低于人类活动影响较弱的土地利用系统;人类活动作用时间长的土地利用系统土壤盐分含量总体低于人类活动作用时间短的土地利用系统;(4)绿洲土壤总体表现为“碳汇”的趋势,土壤质量逐步得到提高,其最主要的原因在于合理的土地利用与科学的管理方式结合;绿洲土壤的“碳汇”积极响应了减轻温室气体排放的东京协定