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Unravelling the nature of Waiparaconus, a pennatulacean (Cnidaria: Octocorallia) from the Late Mesozoic-Early Cainozoic of the Southern Hemisphere

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Integrative Zoology 2014年第2期9卷 111-120页

作者： john S.BUCKERIDGE Hamish j.CAMPBELL Pierre MAURIZOT Earth and Oceanic Systems Group RMIT UniversityVictoriaAustralia GNS Science Lower HuttNew Zealand BRGM The French Geological SurveyNew Caledonia

Enigmatic calcareous conical fossils have been known from marine Paleocene-Eocene sequences of New Zea-land since the early *** recently,similar fossils have been recorded from both Late Cretaceous ma-rine sequences of Western Australia,New Caledonia and Antarctica,and possibly from the Eocene of South *** present paper extends the record to the late Cretaceous of New *** remains are un-like any living taxa,and have been variously interpreted as molluscs(rudistid bivalves),cirripedes(stalked bar-nacles),annelids and inorganic *** to the Cirripedia has been refuted by Buckeridge(1983,1993),who proposed that the material would be better placed within the *** investigate this hypothe-sis in light of the New Caledonian material and by comparison with living gorgonians and pennatulaceans,and demonstrate that Waiparaconus is best placed within the *** zelandicus varies in form somewhat,with 3 morphotypes defined and reinforced by *** is provided on the imperative to fit organic remains into known groups,with reflection on what may happen if taxa are left in insertae sedis.

关键词： Cretaceous Early Paleogene pennatulacean Southern Hemisphere Waiparaconus

Central role of the LEAFY COTYLEDON1 transcription factor in seed development

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j.urnal of Integrative Plant Biology 2019年第5期61卷 564-580页

作者： Leonardo j. j.lie M.Pelletier john j.Harada Department of Plant Biology and Plant Biology Graduate Group University of CaliforniaDavis USA

Seed development is a complex period of the flowering plant life *** fertilization,the three main regions of the seed,embryo,endosperm and seed coat,undergo a series of developmental processes that result in the production of a mature seed that is developmentally arrested,desiccated,and metabolically *** processes are highly coordinated,both temporally and spatially,to ensure the proper growth and development of the *** transcription factor,LEAFY COTYLEDON1(LEC1),is a central regulator that controls several aspects of embryo and endosperm development,including embryo morphogenesis,photosynthesis,and storage reserve ***,LEC1 regulates distinct sets of genes at different stages of seed *** its critical importance for seed development,an understanding of the mechanisms underlying LECi's multifunctionality is only beginning to be *** studies describe the roles of specific transcription factors and the hormones,gibberellic acid and abscisic acid,in controlling the activity and transcriptional specificity of LEC1 across seed ***,studies indicate that LEC1 acts as a pioneer transcript!on factor to promote epigenetic reprogramming during *** this review,we discuss the mechanisms that enable LEC1 to serve as a central regulator of seed development.

关键词： Seed development flowering plant seed development

Investigating Magnetic Field Orientation as an Operational Parameter in Thermoelectric MHD Solidification

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j.urnal of Iron and Steel Research International 2012年第S1期19卷 260-264页

作者： A.kao K.Pericleous School of Computing and Mathematical Sciences University of GreenwichLondonSE 10 9LS UK

A fully coupled 3-dimensional numerical model is used to analyse the effect of magnetic field orientation on dendritic *** materials that exhibit a significant thermoelectric power,the results show significant differences in the dendritic morphology for different orientations of the *** variations can be attributed to fluid flow generated through Thermoelectric Magnetohydrodynamics.A simplified,steady-state,low-field solution during the early stages of growth is used to describe how the fluid flow alters with the orientation of the field and how these flow features can lead to the final morphologies for well developed dendrites.

关键词： thermoelectric MHD magnetic field orientation dendritic growth

Induction of Volatile Organic Compounds of Lycopersicon esculentum Mill. and Its Resistance to Botrytis cinerea Pers. by Burdock Oligosaccharide

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j.urnal of Integrative Plant Biology 2006年第5期48卷 550-557页

作者： Pei-Qing He Li Tian kao-Shan Chen Lin-Hua Hao Guang-You Li First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Qingdao University of Science and Technology Qingdao 266061 China Shool of Life Sciences Shandong University Jinan 250100 China

In the present study, we investigated the induction of volatile organic compounds （VOCs） of Lycoperslcon esculentum Mill. and its resistance to Botrytis cinerea Pers. by burdock oligosaccharlde. The disease severity of L. esculentum was evaluated 48 h after treatment with 0.6% burdock oligosaccharlde, followed by inoculation with a spore suspension of B. cinerea. The formation of O2＇, the activity of lipoxygenases （LOX）, peroxidase （POD）, cataiase （CAT）, and superoxide dismutase （SOD）, and the quantity and quallty of changes In VOCs were determined a period of time after treatment with 0.6% burdock ollgosaccharide. The results demonstrated that the disease index in treated plants was decreased by 42.5% compared with control 96 h after Inoculation. The production of O2＇ reached a maximum 6 h after treatment （1.36-fold compared with control）. There was an increase in LOX, POD, CAT and SOD activity in response to burdock oligosaccharide treatment and the enzymes showed different trends in the time-course of induction. At 120 h after treatment, （E）-2-hexenal was increased by 92% compared with control, whereas methyl salicylate showed a gradual Increase with induction period. Previous results had demonstrated that chitosan elicitor enhanced the production VOCs of L. esculentum and decreased plant susceptibility towards B. clnerea. Together, these findings suggest that increasing the production of VOCs in response to burrdock oligosaccharide may be an important mechanism for L. esculentumin its defense against pathogens, in addition, burrdock oligosaccharlde may act as a potent elicitor of resistance to disease in L. esculentum.

关键词： burdock oligosaccharide induction Lycopersicon esculentum resistance volatile organic compounds.

Women and curiosity in early modern England and France

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Women and curiosity in early modern England and France

Comparison of esophageal capsule endoscopy and esophagogastroduodenoscopy for diagnosis of esophageal varices

作者： Cottegnies Line. Parageau Sandrine. (1955-)Thompson john j.

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World j.urnal of Gastroenterology 2008年第28期14卷 4480-4485页

作者： Catherine T Frenette john G Kuldau Donald j.Hillebrand j.ll Lane Paul j.Pockros Division of Gastroenterology and Hepatology Scripps ClinicLa JollaCaliforniaSan Francisco 94115United States

AIM： To investigate the utility of esophageal capsule endoscopy in the diagnosis and grading of esophageal varices. METHODS： Cirrhotic patients who were undergoing esophagogastroduodenoscopy （EGD） for variceal screening or surveillance underwent capsule endoscopy. Two separate blinded investigators read each capsule endoscopy for the following results： variceal grade, need for treatment with variceal banding or prophylaxis with beta-blocker therapy, degree of portal hypertensive gastropathy, and gastric varices. RESULTS： Fifty patients underwent both capsule and EGD. Forty-eight patients had both procedures on the same day, and 2 patients had capsule endoscopy within 72 h of EGD. The accuracy of capsule endoscopy to decide on the need for prophylaxis was 74%, with sensitivity of 63% and specificity of 82%. Interrater agreement was moderate （kappa = 0.56）. Agreement between EGD and capsule endoscopy on grade of varices was 0.53 （moderate）. Inter-rater reliability was good （kappa = 0.77）. In diagnosis of portal hypertensive gastropathy, accuracy was 57%, with sensitivity of 96% and specificity of 17%. Two patients had gastric varices seen on EGD, one of which was seen on capsule endoscopy. There were no complications from capsule endoscopy.CONCLUSION： We conclude that capsule endoscopy has a limited role in deciding which patients would benefit from EGD with banding or beta-blocker therapy. More data is needed to assess accuracy for staging esophageal varices, PHG, and the detection of gastric varices.

关键词： Esophageal varices Capsule endoscopy Portal hypertension

Evaluating alternative stem cell hypotheses for adult corneal epithelial maintenance

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World j.urnal of Stem Cells 2015年第2期7卷 281-299页

作者： john D West Natalie j.Dorà j.Martin Collinson Genes and Development Group Centre for Integrative PhysiologyCollege of Medicine and Veterinary MedicineUniversity of Edinburgh Institute of Medical Sciences School of Medical SciencesCollege of Life Sciences and MedicineForesterhillUniversity of Aberdeen

In this review we evaluate evidence for three different hypotheses that explain how the corneal epithelium is maintained. The limbal epithelial stem cell(LESC)hypothesis is most widely accepted. This proposes that stem cells in the basal layer of the limbal epithelium, at the periphery of the cornea, maintain themselves and also produce transient(or transit) amplifying cells(TACs). TACs then move centripetally to the centre of the cornea in the basal layer of the corneal epithelium and also replenish cells in the overlying suprabasal layers. The LESCs maintain the corneal epithelium during normal homeostasis and become more active to repair significant wounds. Second, the corneal epithelial stem cell(CESC) hypothesis postulates that, during normal homeostasis, stem cells distributed throughout the basal corneal epithelium, maintain the tissue. According to this hypothesis, LESCs are present in the limbus but are only active during wound healing. We also consider a third possibility, that the corneal epithelium is maintained during normal homeostasis by proliferation of basal corneal epithelial cells without any input from stem cells. After reviewing the published evidence, we conclude that the LESC and CESC hypotheses are consistent with more of the evidence than the third hypothesis, so we do not consider this further. The LESC and CESC hypotheses each have difficulty accounting for one main type of evidence so we evaluate the two key lines of evidence that discriminate between them. Finally, we discuss how lineage-tracing experiments have begun to resolve the debate in favour of the LESC hypothesis. Nevertheless, it also seems likely that some basal corneal epithelial cells can act as long-term progenitors if limbal stem cell function is compromised. Thus, this aspect of the CESC hypothesis may have a lasting impact on our understanding of corneal epithelial maintenance, even if it is eventually shown that stem cells are restricted to the limbus as proposed by the

关键词： Eye Cornea Corneal epithelium Limbalepithelium Stem cell Lineage tracing

Perinatal and early life risk factors for inflammatory bowel disease

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World j.urnal of Gastroenterology 2011年第6期17卷 743-749页

作者： Stephen E Roberts Clare j.Wotton john G Williams Myfanwy Griffith Michael j.Goldacre College of Medicine Swansea University Unit of Health-Care Epidemiology Department of Public HealthUniversity of Oxford

AIM:To investigate associations between perinatal risk factors and subsequent inflammatory bowel disease (IBD) in children and young ***:Record linked abstracts of birth registrations,maternity,day case and inpatient admissions in a defined population of southern *** of 20 perinatal factors relating to the maternity or the birth:maternal age,Crohn's disease (CD) or ulcerative colitis (UC) in the mother,maternal social class,marital status,smoking in pregnancy,ABO blood group and rhesus status,pre-eclampsia,parity,the infant's presentation at birth,caesarean delivery,forceps delivery,sex,number of babies delivered,gestational age,birthweight,head circumference,breastfeeding and Apgar scores at one and five ***:Maternity records were present for 180 children who subsequently developed *** analysis showed increased risks of CD among children of mothers with CD (P=0.011,based on two cases of CD in both mother and child) and children of mothers who smoked during *** analysis confirmed increased risks of CD among children of mothers who smoked (odds ratio=2.04,95% CI=1.06-3.92) and for older mothers aged 35+ years (4.81,2.32-9.98).Multivariate analysis showed that there were no significant associations between CD and 17 other perinatal risk factors *** also showed that,for UC,there were no significant associations with the perinatal factors ***:This study shows an association between CD in mother and child;and elevated risks of CD in children of older mothers and of mothers who smoked.

关键词： Crohn's disease Ulcerative colitis Perinatal risk factors Record linkage

Research methods in psychology / 6th ed. 6th ed.

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