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    题名 作者 年代 出处 被引量
1埃达克岩:关于其成因的一些不同观点显示文摘埃达克岩的概念是十多年前提出来的,指由俯冲的年轻洋壳熔融形成的火成岩。自从最初在现代岛弧近十个地方报道埃达克岩以来,新近又在几个地方发现有埃达克岩(如日本西南部,外墨西哥火山岩带,等等)。但是,过去十多年的研究也表明,埃达克岩可以由俯冲期间的其它过程产生(例如,沿俯冲板片的撕裂边,留在上地幔中的板片残余等)。另外,埃达克岩似乎与一些岩石是共生组合,这些岩石包括高镁安山岩、富Nb的弧玄武岩(NEAB),还可能有玻安岩(几个研究者已在玻安岩中发现有埃达克岩的组分)。高镁安山岩不是来自埃达克与地幔的相互作用(Adak-type),就是来自此相互作用期间地幔的熔融(Piip-tyPe);富Nb的弧玄武岩,据认为是来自一种被埃达克岩广泛交代的地幔的部分熔融。作为一个新的岩套,埃达克岩交代火山岩系列已被建议用来解释各种岩石组合。此外,大量的富Nb弧玄武岩也已被发现包含有超镁铁质的地幔包体,而这些包体有高亏损地幔与埃达克岩反应的明显证据。 关于主要与下地壳熔融而不是与俯冲板片有关的埃达克岩的起源已提出几种假说。一个模型认为,下地壳熔融出现在玄武质岩浆底侵下地壳时。但是,有许多理由似乎可以排除这种模式。另一种模型认为,在大陆地壳很厚的区域,下地壳可能变成榴辉岩,从而拆离并下沉到地幔中(?Marc J DEFANT 许继峰 Pavel KEPEZHINSKAS 王强 张旗 肖龙 2002岩石学报2002,18,2:206
2Developmental dysplasia of the hip: What has changed in the last 20 years?显示文摘Developmental dysplasia of the hip(DDH) describes the spectrum of structural abnormalities that involve the growing hip. Early diagnosis and treatment is critical to provide the best possible functional outcome. Persistence of hip dysplasia into adolescence and adulthood may result in abnormal gait, decreased strength and increased rate of degenerative hip and knee joint disease. Despite efforts to recognize and treat all cases of DDH soon after birth, diagnosis is delayed in some children, and outcomes deteriorate with increasing delay of presentation. Different screening programs for DDH were implicated. The suspicion is raised based on a physical examination soon after birth. Radiography and ultrasonography are used to confirm the diagnosis. The role of other imaging modalities, such as magnetic resonance imaging, is still undetermined; however, extensive research is underway on this subject. Treatment depends on the age of the patient and the reducibility of the hip joint. At an early age and up to 6 mo, the main treatment is an abduction brace like the Pavlik harness. If this fails, closed reduction and spica casting is usually done. After the age of 18 mo, treatment usually consists of open reduction and hip reconstruction surgery. Various treatment protocols have been proposed. We summarize the current practice for detection and treatment of DDH, emphasizing updates in screening and treatment during the last two decades.Pavel Kotlarsky Reuben Haber Victor Bialik Mark Eidelman 2015World Journal of Orthopedics2015,6,11:52
3The role of gut microbiota(commensal bacteria)and the mucosal barrier in the pathogenesis of inflammatory and autoimmune diseases and cancer:contribution of germ-free and gnotobiotic animal models of human diseases显示文摘Metagenomic approaches are currently being used to decipher the genome of the microbiota(microbiome),and,in parallel,functional studies are being performed to analyze the effects of the microbiota on the host.Gnotobiological methods are an indispensable tool for studying the consequences of bacterial colonization.Animals used as models of human diseases can be maintained in sterile conditions(isolators used for germ-free rearing)and specifically colonized with defined microbes(including non-cultivable commensal bacteria).The effects of the germ-free state or the effects of colonization on disease initiation and maintenance can be observed in these models.Using this approach we demonstrated direct involvement of components of the microbiota in chronic intestinal inflammation and development of colonic neoplasia(i.e.,using models of human inflammatory bowel disease and colorectal carcinoma).In contrast,a protective effect of microbiota colonization was demonstrated for the development of autoimmune diabetes in non-obese diabetic(NOD)mice.Interestingly,the development of atherosclerosis in germ-free apolipoprotein E(ApoE)-deficient mice fed by a standard low-cholesterol diet is accelerated compared with conventionally reared animals.Mucosal induction of tolerance to allergen Bet v1 was not influenced by the presence or absence of microbiota.Identification of components of the microbiota and elucidation of the molecular mechanisms of their action in inducing pathological changes or exerting beneficial,disease-protective activities could aid in our ability to influence the composition of the microbiota and to find bacterial strains and components(e.g.,probiotics and prebiotics)whose administration may aid in disease prevention and treatment.Helena Tlaskalova-Hogenova Renata Stepankova Hana Kozakova Tomas Hudcovic Luca Vannucci Ludmila Tuckova Pavel Rossmann TomasHrncır Miloslav Kverka Zuzana Zakostelska Klara Klimesova Jaroslava Pribylova Jirina Bartova Daniel Sanchez Petra Fundova Dana Borovska Dagmar Sru˚tkova Zdenek Zıdek Martin Schwarzer Pavel Drastich David P Funda 2011Cellular & Molecular Immunology2011,8,2:47
4Treatment of coronary in-stent restenosis: a systematic review显示文摘冠的 stent 培植显著地改进了经皮的冠的干预并且启用了平凡汽球 angioplasty 的早复杂并发症的管理。然而,新复杂并发症伴随了这些改进:从 neointimal 增生产生的 in-stent 狭窄(ISR ) 。在冠的 angioplasty 以后的 ISR 当前是这个方法的主要限制之一,导致 exertional 心绞痛或急性冠的症候群的复发。在赤裸金属的 stent (BMS ) 以后的 ISR 的临床的发生培植是近似 20%-35% 。drug-eluting stents (DES ) 的使用在 ISR 的出现导致了进一步的减少到 5%-10% 。源于控制临床的研究的证据建议 DES 和 drug-eluting 汽球导管(初上舞台的人) 提供临床的最好, angiographic 导致 ISR 的处理。我们为 BMS-ISR 和 DES-ISR 拿了 pathophysiology,诊断和处理选择的系统的评论。我们讨论最近的 randomised 研究,比较为新 biovascular scafolds 和 scafold 狭窄的话题的 BMS 或 DES-ISR 处理,以及使用使用的不同 DES 或初上舞台的人。Leos Pleva Pavel Kukla Ota Hlinomaz 2018Journal of Geriatric Cardiology2018,15,2:39
5有机污染环境植物修复技术显示文摘利用物理、化学方法修复有机污染环境,费用昂贵,而且还可能使当地的生态资源难以再利用,对于大面积污染土壤也难以实施。植物修复,利用植物吸收、降解以及根际圈降解的作用方式将有机污染物从环境中彻底去除,具有处理费用相对低廉、对环境扰动少和使资源可持续利用的特点,目前已成为环境科学领域的一大热点和前沿。本文对环境中主要有机污染物的发生机理、近年来植物修复有机污染的研究进展做一综述,并对有机污染植物修复的强化措施进行了展望。魏树和 周启星 Pavel V.Koval Galina A.Belogolova 2006生态学杂志2006,25,6:31
6能量路由器中双有源桥直流变换器多目标优化控制策略显示文摘为提升能量路由器中双有源桥(DAB)变换器的传输效率,同时改善系统的动态特性,该文提出一种基于扩展移相的输出电压模型预测控制与梯度下降算法实现回流功率优化的混合控制策略。首先,建立DAB变换器在单移相和扩展移相控制下的传输功率数学模型,分析回流功率产生机理,并推导扩展移相控制下的输出电压状态空间平均化方程;其次,在DAB变换器输出电压模型预测控制基础上提出基于梯度下降算法的回流功率优化策略。搭建小功率实验样机,并与传统单移相控制进行对比,实验结果证明了该文所提控制策略的有效性及正确性。周兵凯 杨晓峰 张智 李泽杰 郑琼林 Pavel Kobrle 2020电工技术学报2020,35,14:32
7基于VSD模型的黄土高原丘陵沟壑区县域生态脆弱性评价——以甘肃省临洮县为例显示文摘以甘肃省临洮县为例,采用VSD模型,通过暴露度、敏感性和适应能力分解生态脆弱性,构建了包含自然因素和人为因素的综合评价指标体系,开展脆弱性评价与分区。分析结果表明:研究区内极脆弱区、高脆弱区、较脆弱区、脆弱区和低脆弱区分别占16.10%、17.96%、30.65%、30.65%和4.64%,北部和东部山区脆弱性较高,南部地区脆弱性较低;影响研究区生态脆弱性的主要因素有降水量、植被覆盖度、土壤侵蚀类型、坡度等自然因素。根据分区结果,对于生态脆弱区实施易地搬迁工程的对象提出了相应的建议。陈枫 李泽红 董锁成 任扬 李静楠 Pavel V.Rykov 2018干旱区资源与环境2018,32,11:25
8Distinct gut microbiota profiles in patients with primary sclerosing cholangitis and ulcerative colitis显示文摘AIM To characterize the gut bacterial microbiota of patients with primary sclerosing cholangitis(PSC) and ulcerative colitis(UC).METHODS Stool samples were collected and relevant clinical data obtained from 106 study participants, 43 PSC patients with(n = 32) or without(n = 11) concomitant inflammatory bowel disease, 32 UC patients, and 31 healthy controls. The V3 and V4 regions of the 16 S ribosomal RNA gene were sequenced on Illumina Mi Seq platform to cover low taxonomic levels. Data were further processed in QIIME employing Ma As Lin and LEf Se tools for analysis of the output data.RESULTS Microbial profiles in both PSC and UC were characterized by low bacterial diversity and significant change in global microbial composition. Rothia, Enterococcus, Streptococcus, Veillonella, and three other genera were markedly overrepresented in PSC regardless of concomitant inflammatory bowel disease(IBD). Rothia, Veillonella and Streptococcus were tracked to the species level to identify Rothia mucilaginosa, Streptococcus infantus, S. alactolyticus, and S. equi along with Veillonella parvula and V. dispar. PSC was further characterized by decreased abundance of Adlercreutzia equolifaciens and Prevotella copri. Decrease in genus Phascolarctobacterium was linked to presence of colonic inflammation regardless of IBD phenotype. Akkermansia muciniphila, Butyricicoccus pullicaecorum and Clostridium colinum were decreased in UC along with genus Roseburia. Low levels of serum albumin were significantly correlated with enrichment of order Actinomycetales.CONCLUSION PSC is associated with specific gut microbes independently of concomitant IBD and several bacterial taxa clearly distinguish IBD phenotypes(PSC-IBD and UC).Lukas Bajer Miloslav Kverka Martin Kostovcik Peter Macinga Jiri Dvorak Zuzana Stehlikova Jan Brezina Pavel Wohl Julius Spicak Pavel Drastich 2017World Journal of Gastroenterology2017,23,25:22
9Comparison of three methods for natural gas dehydration显示文摘This paper compares three methods for natural gas dehydration that are widely applied in industry:(1) absorption by triethylene glycol, (2) adsorption on solid desiccants and (3) condensation. A comparison is made according to their energy demand and suitability for use. The energy calculations are performed on a model where 105 Nm3/h water saturated natural gas is processed at 30 °C. The pressure of the gas varies from 7 to 20 MPa. The required outlet concentration of water in natural gas is equivalent to the dew point temperature of -10 °C at gas pressure of 4 MPa.Michal Netusil Pavel Ditl 2011Journal of Natural Gas Chemistry2011,20,5:19
10家禽的性别鉴定方法显示文摘现代家禽生产 ,祖代鸡通过翻肛鉴定性别 ,父母代鸡以羽速 (快慢羽 )判定公母 ,而商品代鸡则以羽色自别雌雄。常规性别鉴定方法耗资费力 ,且慢羽基因 (K)与内源病毒基因 (ev 2 1 )紧密连锁 ,导致慢羽鸡群免疫反应降低 ,成活率和产蛋性能下降。以鉴定W染色体上性连锁DNA序列或基因为基础 ,从分子水平上鉴定家禽性别的研究有望填补家禽性别鉴定空白。燕海峰 肖兵南 Pavel Trefil 吴晓林 2001动物学杂志2001,36,6:17
11Etiology and functional status of liver cirrhosis by ^(31)P MR spectroscopy显示文摘AIM: To assess the functional status and etiology of liver cirrhosis by quantitative 31p magnetic resonance spectroscopy (MRS).METHODS: A total of 80 patients with liver cirrhosis of different etiology and functional status described by Child-Pugh score were examined and compared to 11 healthy volunteers. MR examination was performed on a 1.5 T imager using a 1H/31P surface coil by the 2D chemical shift imaging technique.Absolute concentrations of phosphomonoesters (PME),phosphodiesters (PDE), inorganic phosphate (Pi) and adenosine triphosphate (ATP) were measured.RESULTS: MRS changes reflected the degree of liver dysfunction in all the patients as well as in individual etiological groups. The most important change was a decrease of PDE. It was possible to distinguish alcoholic,viral and cholestatic etiologies based on MR spectra.Alcoholic and viral etiology differed in PDE (alcoholic,viral, controls: 6.5±2.3, 6.5±3.1, 10.8±2.7 mmol/L,P<0.001) and ATP (alcoholic, viral, controls: 2.9±0.8, 2.8±0.9, 3.7±1.0 mmol/L, P<0.01) from the control group.Unlike viral etiology, patients with alcoholic etiology also differed in Pi (alcoholic, controls: 1.2±0.4, 1.6±0.6mmol/L, P<0.05) from controls. No significant changes were found in patients with cholestatic disease and controls; nevertheless, this group differed from both alcoholic and viral groups (cholestatic, alcoholic, viral: 9.4±2.7, 6.5±2.3, 6.5±3.1 mmol/L, P<0.005) in PDE.CONCLUSION: 31p MRS can significantly help in noninvasive separation of different etiological groups leading to liver cirrhosis. In addition, MRS changes reflect functional liver injury.Monika Dezortova Pavel Taimr Antonin Skoch Julius Spicak Milan Hajek 2005World Journal of Gastroenterology2005,11,44:17
12极地冰钻关键技术研究进展显示文摘极地冰钻技术是获取冰芯,研究冰盖-冰架-海洋相互作用,以及获取极地冰下基岩与冰下水环境样品,开展冰下环境探测的重要手段。目前极地冰钻技术的难点与前沿主要包括深冰芯钻探、冰架热水钻、冰下基岩钻和冰下水环境采样与观测技术。本文针对以上4个极地冰钻关键技术,对国内外相关技术的研究进展与项目开展情况进行了总结与梳理。综合来看,虽然我国开展极地钻探技术研究起步较晚,但随着我国极地战略不断推进,我国的极地冰钻关键技术与装备的研究正持续向着赶超极地钻探强国方向迈进,这必将为我国的极地科学研究提供强有力的技术支撑。张楠 王亮 Pavel Talalay 范晓鹏 王如生 杨阳 洪嘉琳 宫达 孙友宏 李院生 李冰 2020探矿工程(岩土钻掘工程)2020,47,2:13
13基于B-spline和正则化算法的低轨卫星轨道平滑显示文摘本文提出了一个利用纯几何轨道和力模型的新算法来计算精确且相对平滑的卫星轨道.该法将一个纯几何轨道表达为一个B-spline的线性组合,线性组合的系数可以由最小二乘法估计获得.力模型通过计算加速度来附加约束.为了平衡几何轨道的点位误差和加速度的不精确,一个基于“广义交互确认(GCV,generalizedcross-validation)”的正则化算法运用其中.由于B-spline的本地控制性,该方法的计算效率相当高.本文的数值分析表明了该法的有效性.模拟计算的结论是:带加速度约束较不带加速度约束的平滑效果好.力模型越精确,平滑的轨道就越精确.三个月的CHAMP实测轨道数据处理结果表明,平滑后的轨道改进了重力场模型.柳响林 Pavel Ditmar 2006地球物理学报2006,49,1:10
14支架自显影定位法体外开窗技术在主动脉弓部腔内修复术中的应用:附113例国际多中心病例回顾性分析显示文摘背景与目的:胸主动脉腔内修复术(TEVAR)已成为治疗降主动脉疾病的一线治疗方式。在治疗累及主动脉弓部疾病时,体外开窗(PMF)是目前常用于重建弓部分支动脉的技术之一。它是指在选择合适的主动脉覆膜支架后,根据弓上分支动脉的位置,在覆膜支架相应位置上除去覆膜,建立人造的“窗孔”,在将有窗孔的大动脉支架准确对位释放后再释放分支支架。本文介绍一种利用主动脉支架本身所携带的不透X线标志快速、准确地将窗孔与分支动脉开口对准的开窗方法—支架自显影定位PMF技术(S-F技术),并通过总结利用该方法进行TEVAR的一组患者临床资料和手术以及随访数据,探讨利用S-F技术在主动脉弓部疾病腔内治疗中的技术特点和其应用价值。方法:回顾性分析2015年12月—2020年6月利用S-F技术行TEVAR治疗的中国湖南中南大学湘雅二医院血管外科和其他7个国家的国家级血管外科中心共113例主动脉弓部疾病患者的基本数据、术中技术数据和术后随访数据。结果:患者均根据S-F技术的操作标准流程进行的TEVAR,即时手术成功率为100%,共植入胸主动脉覆膜支架118枚,其中植入桥接支架35例。手术时间(62.9±17.4)min,X线操作时间(23.1±9.8)min,造影剂用量(81.2±22.5)mL。术中开窗对位准确率为98.2%。补救性植入烟囱支架1例(0.9%),矫正后对位回准1例(0.9%)。开窗同时保留弓上三分支动脉2例(1.8%),开窗同时保留左颈总动脉(LCCA)和左锁骨下动脉(LSA)6例(5.3%),保留LSA 110例(97.3%)。术后1个月内无死亡病例,无严重并发症发生。术后1周复查发现Ⅰ型内漏7例(6.2%)。随访时间中位时间24.5个月,死亡2例(1.8%);术后分支动脉闭塞3例(2.7%),分别发生在术后3个月(2例)和术后6个月(1例)。结论:S-F技术为治疗累及主动脉弓部疾病重建弓上分支动脉提供了一种可供选择的方法,是全腔内重建主动脉弓部方法技术上的一项进步。舒畅 李鑫 李全明 何昊 黎明 王暾 杨晨紫 王沫 周海洋 JoséFernando Teixeira Suko Adiarto Tao Fan Bogdan Cherpark Imaev Timur Makhkamov Najmiddin Pavel Charnahlaz Giorgi Kheladze 2020中国普通外科杂志2020,29,12:10
15Treatment strategies for colorectal carcinoma with synchronous liver metastases: Which way to go?显示文摘AIM: To offer an up-to-date review of all availabletreatment strategies for patients with synchronous colorectal liver metastases(CLM).METHODS: A comprehensive literature search was performed to identify articles related to the management of patients with synchronous CLM. A search of the electronic databases PubMed, MEDLINE, and Google Scholar was conducted in September 2014.The following search terms were used: synchronous colorectal liver metastases, surgery, stage Ⅳ colorectal cancer, liver-first approach, and up-front hepatectomy.These terms were employed in various combinations to maximize the search. Only articles written in English were included. Particular attention was devoted to studies and review articles that were published within the last six years(2009-2014). Additional searches of the cited references from primary articles were performed to further improve the review. The full texts of all relevant articles were accessed by two independent reviewers.RESULTS: Poor long-term outcomes of patients with synchronous CLM managed by a traditional treatment strategy have led to questions about the timing and sequence of possible therapeutic interventions. Thus,alternative paradigms called reverse strategies have been proposed. Presently, there are four treatment strategies available:(1) primary first approach(or traditional approach) comprises resection of the primary colorectal tumor followed by chemotherapy;subsequent liver resection is performed 3-6 mo after colorectal resection(provided that CLM are still resectable);(2) simultaneous resection of the primary colorectal tumor and CLM during a single operation presents intriguing options for a highly select group of patients, which can be associated with significant postoperative morbidity;(3) liver-first(or chemotherapy-first) approach comprises preoperative chemotherapy(3-6 cycles) followed by liver resection,adjuvant chemotherapy, and resection of the primary colorectal tumor(it is best suited for patients withasymptomatic primary tumors and initially unresectable or marginally resectable CLM); and(4) up-front hepatectomy(or 'true' liver-first approach) includes liver resection followed by adjuvant chemotherapy,colorectal resection, and adjuvant chemotherapy(strategy can be offered to patients with asymptomatic primary tumors and initially resectable CLM).CONCLUSION: None of the aforementioned strategies appears inferior. It is necessary to establish individual treatment plans in multidisciplinary team meetings through careful appraisal of all strategies.Peter Ihnát Petr Vávra Pavel Zonca 2015World Journal of Gastroenterology2015,21,22:10
16Expansion of the hepatocellular carcinoma Milan criteria in liver transplantation: Future directions显示文摘Milan criteria are currently the benchmark related to liver transplantation(LT) for hepatocellular carcinoma. However, several groups have proposed different expanded criteria with acceptable results. In this article, we review the current status of LT beyond the Milan criteria in three different scenarios-expanded criteria with cadaveric LT, downstaging to Milan criteria before LT, and expansion in the context of adult living donor LT. The review focuses on three main questions: what would the impact of the expansion beyond Milan criteria be on the patients on the waiting list; whether the dichotomous criteria(yes/no) currently used are appropriate for LT or continuous survival estimations, such as the one of 'Metroticket' and whether it should enter into the clinical practice; and, whether the use of living donor LT in the context of expansion beyond Milan criteria is justified.Mihai-Calin Pavel Josep Fuster 2018World Journal of Gastroenterology2018,24,32:10
17Autonomy in materials research: a case study in carbon nanotube growth显示文摘Advances in materials are an important contributor to our technological progress,and yet the process of materials discovery and development itself is slow.Our current research process is human-centred,where human researchers design,conduct,analyse and interpret experiments,and then decide what to do next.We have built an Autonomous Research System(ARES)—an autonomous research robot capable of first-of-its-kind closed-loop iterative materials experimentation.ARES exploits advances in autonomous robotics,artificial intelligence,data sciences,and high-throughput and in situ techniques,and is able to design,execute and analyse its own experiments orders of magnitude faster than current research methods.We applied ARES to study the synthesis of singlewalled carbon nanotubes,and show that it successfully learned to grow them at targeted growth rates.ARES has broad implications for the future roles of humans and autonomous research robots,and for human-machine partnering.We believe autonomous research robots like ARES constitute a disruptive advance in our ability to understand and develop complex materials at an unprecedented rate.Pavel Nikolaev Daylond Hooper Frederick Webber Rahul Rao Kevin Decker Michael Krein Jason Poleski Rick Barto Benji Maruyama 2016npj Computational Materials2016,,1:9
18Preventive effect of a pectic polysaccharide of the common cranberry Vaccinium oxycoccos L. on acetic acid-induced colitis in mice显示文摘AIM: To study isolation and chemical characterization of pectin derived from the common cranberry Vaccinium oxycoccos L. (oxycoccusan OP) and the testing of its preventive effect on experimental colitis.METHODS: Mice were administrated orally with OP two days prior to a rectal injection of 5% acetic acid and examined for colonic damage 24 h later. Colonic inflammation was characterized by macroscopical injury and enhanced levels of myeloperoxidase activity measured spectrophotometrically with o-phenylene diamine as the substrate. The mucus contents of the colon were determined by the Alcian blue dye binding method. Vascular permeability was estimated using 4% Evans blue passage after i.p. injection of 0.05 mol/L acetic acid. RESULTS: In the mice treated with OP, colonic macroscopic scores (1.1 ± 0.4 vs 2.7, P < 0.01) and the total square area of damage (10 ± 2 vs 21 ± 7, P < 0.01) were significantly reduced when compared with the vehicle-treated colitis group. OP was shown to decrease the tissue myeloperoxidase activity in colons (42 ± 11 vs 112 ± 40, P < 0.01) and enhance the amount of mucus of colitis mice (0.9 ± 0.1 vs 0.4 ± 0.1, P < 0.01). The level of colonic malondialdehyde was noted to decrease in OP-pretreated mice (3.6 ± 0.7 vs 5.1 ± 0.8, P < 0.01). OP was found to decrease the inflammatory status of mice as was determined by reduction of vascular permeability (161 ± 34 vs 241 ± 21, P < 0.01). Adhesionof peritoneal neutrophils and macrophages was also shown to decrease after administration of OP (141 ± 50 vs 235 ± 37, P < 0.05).CONCLUSION: Thus, a preventive effect of pectin from the common cranberry, namely oxycoccusan OP, on acetic acid-induced colitis in mice was detected. A reduction of neutrophil infiltration and antioxidant action may be implicated in the protective effect of oxycoccusan.Sergey V Popov Pavel A Markov Ida R Nikitina Sergey Petrishev Vasily Smirnov Yury S Ovodov 2006World Journal of Gastroenterology2006,12,41:9
19YODA-HSP90 Module Regulates Phosphorylation-Dependent Inactivation of SPEECHLESS to Control Stomatal Development under Acute Heat Stress in Arabidopsis显示文摘Stomatal ontogenesis,patterning,and function are hallmarks of environmental plant adaptation,especially to conditions limiting plant growth,such as elevated temperatures and reduced water availability.The specification and distribution of a stomatal cell lineage and its terminal differentiation into guard cells require a master regulatory protein phosphorylation cascade involving the YODA mitogen-activated protein kinase kinase kinase.YODA signaling results in the activation of MITOGEN-ACTIVATED PROTEIN KINASEs(MPK3 and MPK6),which regulate transcription factors,including SPEECHLESS(SPCH).Here,we report that acute heat stress affects the phosphorylation and deactivation of SPCH and modulates stomatal density.By using complem entary molecular,genetic,biochemical,and cell biology approaches,we provide solid evidence that HEAT SHOCK PROTEINS 90(HSP90s)play a crucial role in transducing heat-stress response through the YODA cascade.Genetic studies revealed that YODA and HSP90.1 are epistatic,and they likely function linearly in the same developmental pathway regulating stomata formation.HSP90s interact with YODA,affectits cellular polarization,and modulate the phosphorylation of downstream targets,such as MPK6 and SPCH,under both normal and heat-stress conditions.Thus,HSP90-mediated specification and differentiation of the stomatal cell lineage couples stomatal development to environmental cues,providing an adaptive heat stress response mechanism in plants.Despina Samakovli Tereza Ticha Tereza Vavrdova Miroslav Ovecka Ivan Luptovciak Veronika Zapletalova Anna Kucharova Pavel Krenek Yuliya Krasylenko Theoni Margaritopoulou Loukia Roka Dimitra Milioni George Komis Polydefkis Hatzopoulos Jozef Samaj 2020Molecular Plant2020,13,4:9
20Electronic structure of the SrAl_2O_4:Eu^(2+) persistent luminescence material显示文摘The electronic structure of the strontium aluminate (SrAl2O4:Eu2+) materials was studied with a combined experimental and theoretical approach. The UV-VUV synchrotron radiation was applied in the experimental study while the electronic structure of the non-optimized and optimized crystal structure were investigated theoretically by using the density functional theory. The structure of the va- lence and conduction bands as well as the band gap energy of the material together with the position of the Eu2+ 4f7 8S7/2 ground state were calculated. The calculated band gap energy (6.4 eV) agreed well with the experimental value of 6.6 eV. The valence band consisted mainly of oxygen states whereas the bottom of the conduction band of strontium states. In agreement with the experimental results, the calculated 4f7 8S7/2 ground state of Eu2+ lies in the energy gap of the host. The position of the 4f7 ground state depended on the Coulomb repulsion strength. The position of the 4f7 ground state with respect to the valence and conduction bands was discussed using theoretical and experimental evidence available.Jorma Hls Taneli Laamanen Mika Lastusaari Janne Niittykoski Pavel Novák 2009Journal of Rare Earths2009,27,4:9
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