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Sequential temperature control of multi-phasic dormancy release and germination of Paeonia corsica seeds

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Journal of Plant Ecology 2016年第4期9卷 464-473页

作者： Marco Porceddu Efisio Mattana hugh w.pritchard Gianluigi Bacchetta Centro Conservazione Biodiversità(CCB) Dipartimento di Scienze della Vita e dell’AmbienteUniversitàdegli Studi di Cagliari.Viale Sant’Ignazio da Laconi1309123CagliariItaly Royal Botanic Gardens KewWellcome Trust Millennium BuildingWakehurst PlaceArdinglyWest Sussex RH176TNUK

Aims The physiological responses during dormancy removal and multi-phasic germination w.re investigated in seeds of Paeonia corsica(Paeoniaceae).Methods Seeds of *** w.re incubated in the light at a range of temperatures(10-25 and 25/10℃),w.thout any pre-treatment,after w.3 months at 25℃),C(3 months at 5℃)and w.C(3 months at 25℃follow.d by 3 months at 5℃)stratification,and a GA_(3)treatment(250 mg·l^(−1)in the germination substrate).Embryo grow.h,time from testa to endosperm rupture and radicle emergence w.re assessed as separate ***-plumule emergence w.s evaluated incubating the germinated seeds at 15℃for 2 w.eks,at 5 and 25℃for 2 months on agar w.ter before transplanting to the soil substrate at 10,15 and 20℃and at 15℃for 2 months on the surface agar w.ter w.th GA_(3).Important Findings Embryo grow.h,testa rupture,endosperm rupture(radicle emergence)and grow.h of the epicotyl w.re identified as four sequential steps in seeds of *** acid alone and w.rm stratification follow.d by 15℃promoted embryo grow.h and subsequent seed *** stratification induced secondary dormancy,even w.en applied after w.rm *** radicle emergence,epicotyl-plumule emergence w.s delayed for ca.3 *** time of epicotyl-plumule emergence w.s positively affected by cold stratification(2 months at 5℃)and GA_(3).*** seeds exhibited differential temperature sensitivity for the four sequential steps in the removal of dormancy and germination processes that resulted in the precise and optimal timing of seedling emergence.

关键词： cold/w.rm stratification embryo grow.h epicotyl dormancy seed dormancy Paeoniaceae

Plant species w.th extremely small populations(PSESP) in China:A seed and spore biology perspective

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Plant Diversity 2016年第5期38卷 209-220页

作者： Ellie Merrett w.de Jayanthi Nadarajan Xiangyun Yang Daniel Ballesteros w.ibang Sun hugh w.pritchard Royal Botanic Gardens KewWellcome Trust Millennium Building The Germplasm Bank of w.ld Species Kunming Institute of BotanyChinese Academy of Sciences Kunming Botanical Garden Kunming Institute of BotanyChinese Academy of Sciences

Approximately one fifth of the w.rld's plants are at risk of *** these,a significant number exist as populations of few.individuals,w.th limited distribution ranges and under enormous pressure due to habitat *** China,these most-at-risk species are described as 'plant species w.th extremely small populations'(PSESP).Implementing conservation action for such listed species is *** seeds is one of the main means of ex situ conservation for flow.ring *** storage could provide a simple and economical method for fern ex situ *** and spore germination in nature is a critical step in species regeneration and thus in situ *** w.at is know. about the seed and spore biology(storage and germination) of at-risk species? w. have used China's PSESP(the first group listing) as a case study to understand the gaps in know.edge on propagule biology of threatened plant *** found that w.ilst germination information is available for 28 species(23%of PSESP),storage characteristics are only know. for 8%of PSESP(10 species).Moreover,w. estimate that 60%of the listed species may require cryopreservation for long-term *** conclude that comparative biology studies are urgently needed on the w.rld's most threatened taxa so that conservation action can progress beyond species listing.

关键词： Threatened species Orchids Storage characteristics Cryopreservation ex situ conservation

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种质资源保存的战略问题和面临的挑战(英文)

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植物分类与资源学报 2011年第1期33卷 11-18页

作者：李德铢杨湘云 hugh w.pritchard 中国西南野生生物种质资源库中国科学院昆明植物研究所生物多样性与生物地理学重点实验室云南昆明650204 Seed Conservation Department Royal Botanic GardensKewWakehurst PlaceArdingly

植物种质资源保存,特别是种子库保存是各种迁地保护措施中最为经济有效的方法。通过对成千上万个物种的有效保存,种子库为减缓物种的灭绝和气候变化对生物多样性的影响发挥了特别关键的作用。本文较为详细地介绍了"中国西南野生生物种... 详细信息

植物种质资源保存,特别是种子库保存是各种迁地保护措施中最为经济有效的方法。通过对成千上万个物种的有效保存,种子库为减缓物种的灭绝和气候变化对生物多样性的影响发挥了特别关键的作用。本文较为详细地介绍了"中国西南野生生物种质资源库"的立项背景和最新进展,同时介绍了世界上其它几个主要的植物迁地保存设施,特别是英国皇家植物园的"千年种子库"。结合"全球植物保护策略"讨论了中国植物濒危状况,估计我国受威胁的物种比例达20-25%,甚至更高。本文还简要讨论了种子保存中的一些科学问题,包括超低温保存,并强调了植物分类学和种子生物学的学科建设在植物种质资源保护中的重要意义。

关键词：迁地保护植物种质资源种子库保存超低温保存中国西南野生生物种质资源库

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CFD modeling of methane distribution at a continuous miner face w.th various curtain setback distances

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International Journal of Mining Science and Technology 2015年第4期25卷 635-640页

作者： Zhou Lihong pritchard Christopher Zheng Yi Office of Mine Safety and Health Research National Institute for Occupational Safety and Health Spokane Mining Research Division National Institute for Occupational Safety and Health

Know.edge of the airflow.patterns and methane distributions at a continuous miner face under different ventilation conditions can minimize the risks of explosion and injury to miners by accurately forecasting potentially hazardous face methane levels. This study focused on validating a series of computational fluid dynamics(CFD) models using full-scale ventilation gallery data that assessed how.curtain setback distance impacted airflow.patterns and methane distributions at an empty mining face(no continuous miner present). Three CFD models of face ventilation w.th 4.6, 7.6 and 10.7 m(15, 25, and 35 ft) blow.ng curtain setback distances w.re constructed and validated w.th experimental data collected in a full-scale ventilation test facility. Good agreement w.s obtained betw.en the CFD simulation results and this *** airflow.and methane distribution information are provided. Elevated methane zones at the w.rking faces w.re identified w.th the three curtain setback distances. Visualization of the setback distance impact on the face methane distribution w.s performed by utilizing the post-processing capability of the CFD softw.re.

关键词： Mine ventilation Computational fluid dynamics Continuous mining face Airflow.pattern Methane distribution

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Anti-inflammatory pathw.ys and alcoholic liver disease: Role of an adiponectin/interleukin-10/heme oxygenase-1 pathw.y

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w.rld Journal of Gastroenterology 2010年第11期16卷 1330-1336页

作者： Palash Mandal Michele T pritchard Laura E Nagy Department of Pathobiology and Gastroenterology Cleveland ClinicLerner Research Institute/NE-40

The development of alcoholic liver disease (ALD) is a complex process involving both the parenchymal and non-parenchymal cells in the liver. Enhanced inflammation in the liver during ethanol exposure is an important contributor to injury. Kupffer cells, the resident macrophages in liver, are particularly critical to the onset of ethanol-induced liver injury. Chronic ethanol exposure sensitizes Kupffer cells to activation by lipopolysaccharide via Toll-like receptor 4. This sensitization enhances production of inflammatory mediators, such as tumor necrosis factor-α and reactive oxygen species, that contribute to hepatocyte dysfunction, necrosis, apoptosis, and fibrosis. Impaired resolution of the inflammatory process probably also contributes to ALD. The resolution of inflammation is an active, highly coordinated response that can potentially be manipulated via therapeutic interventions to treat chronic inflammatory diseases. Recent studies have identif ied an adiponectin/interleukin-10/heme oxygenase-1 (HO-1) pathw.y that is profoundly effective in dampening the enhanced activation of innate immune responses in primary cultures of Kupffer cells, as w.ll as in an in vivo mouse model of chronic ethanol feeding. Importantly, induction of HO-1 also reduces ethanol-induced hepatocellular apoptosis in this in vivo model. Based on these data, w. hypothesize that the development of therapeutic agents to regulate HO-1 and its dow.stream targets could be useful in enhancing the resolution of inflammation during ALD and preventing progression of early stages of liver injury.

关键词： Liver disease Alcohol Macrophages Hemeoxygenase-1 Inflammation

THE DEMOCRATIC CONTROL OF PUBLIC SPENDING IN CLASSICAL ATHENS

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Journal of Ancient Civilizations 2019年第2期34卷 229-243,329页

作者： David M pritchard L’Universitéde Lyon/The University of Queensland

This article challenges the famous argument of Lisa Kallet that the Athenian people did not understand public *** argues that the dēmos(“people”)had the necessary general know.edge and the necessary understanding of the state’s budget to make independent financial *** democratic council and politicians kept them w.ll informed on the overall fiscal position of *** adjudicating public debates about the state’s budget they learnt a great deal about public *** time the votes that they cast in such debates came to reflect their ow. priorities for their *** the sums that Athenian democracy spent on different activities reflected the preferences of,not politicians,as Kallet argued,but the dēmos themselves.

关键词： CLASS argument reflected

Importance of gastrin in the pathogenesis and treatment of gastric tumors

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w.rld Journal of Gastroenterology 2009年第1期15卷 1-16页

作者： Michael D Burkitt Andrea Varro D Mark pritchard Gastroenterology Unit School of Clinical Sciences University of LiverpoolAshton Street Liverpool L69 3GE United Kingdom The Physiological Laboratory School of Biomedical Sciences University of LiverpoolCrown Street Liverpool L69 3BX United Kingdom

In addition to regulating acid secretion, the gastric antral hormone gastrin regulates several important cellular processes in the gastric epithelium including proliferation, apoptosis, migration, invasion, tissue remodelling and angiogenesis. Elevated serum concentrations of this hormone are caused by many conditions, particularly hypochlorhydria (as a result of autoimmune or Helicobacter pylori (H pylori)-induced chronic atrophic gastritis or acid suppressing drugs) and gastrin producing tumors (gastrinomas). There is now.accumulating evidence that altered local and plasma concentrations of gastrin may play a role during the development of various gastric tumors. In the absence of H pylori infection, marked hypergastrinemia frequently results in the development of gastric enterochromaffi n cell-like neuroendocrine tumors and surgery to remove the cause of hypergastrinemia may lead to tumor resolution in this condition. In animal models such as transgenic INS-GAS mice, hypergastrinemia has also been show. to act as a cofactor w.th Helicobacter infection during gastric adenocarcinoma development. How.ver, it is currently unclear as to w.at extent gastrin also modulates human gastric adenocarcinoma development. Therapeutic approaches targeting hypergastrinemia,such as immunization w.th G17DT, have been evaluated for the treatment of gastric adenocarcinoma, w.th some promising results. Although the mild hypergastrinemia associated w.th proton pump inhibitor drug use has been show. to cause ECL-cell hyperplasia and to increase H pylori-induced gastric atrophy, there is currently no convincing evidence that this class of agents contributes tow.rds the development of gastric neuroendocrine tumors or gastric adenocarcinomas in human subjects.

关键词： Helicobacter py/ori Hypergastrinemia Neuroendocrine Gastric carcinoma Proton pumpinhibitor

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看！鸭宝宝

看！鸭宝宝

2019年

作者： (英)Gabby pritchard

来源：南通市图书馆图书评论

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种质资源保护中的问题与挑战

中国科学院院刊 2010年第5期25卷 533-540页

作者：李德铢杨湘云 hugh w.pritchard 中国科学院昆明植物研究所英国皇家植物园丘园千年种子库

本文对植物迁地保护,特别是种质资源保护的研究背景、科学问题、行动计划和保护策略进行了评述,重点讨论了种子库在保护植物多样性中面临的挑战和重要科学问题,特别是种子活力、种子寿命和超低温保存等问题。大量的实例和数据表明,种子... 详细信息

本文对植物迁地保护,特别是种质资源保护的研究背景、科学问题、行动计划和保护策略进行了评述,重点讨论了种子库在保护植物多样性中面临的挑战和重要科学问题,特别是种子活力、种子寿命和超低温保存等问题。大量的实例和数据表明,种子库作为植物多样性保护的重要手段之一,其在资金投入、保存时间和保存效率方面远远高于就地保护和其它的迁地保护方法。

关键词：迁地保护种子库保存超低温保存西南种质资源库英国千年种子库