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The induction of Sinorhizobium meliloti c_(4)-dicarboxylate transport system (Dct) is regulated by oxygen concentration

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chinese Science Bulletin 2005年第17期50卷 1891-1895页

作者： WEN Jin NAN Beiyan fergal O'Gara WANG Yiping National Laboratory of Protein Engineering and Plant Genetic Engineering College of Life Sciences Peking University Beijing 100871 China Microbiology Department University College Cork National Unversity Ireland Cork Ireland

The Sinorhizobium meliloti c4-dicarboxylate transport (Dct) system is essential for symbiotic nitrogen fixation. The dctA gene, encoding the c4-dicarboxylate per-mease, is expressed in both free living and symbiotic cells. But in free living cells expression of dctD and dctB is abso-lutely required for the expression of dctA. In this study, in order to investigate the effect of oxygen concentration on the induction of Dct system, E. coli DH5α strain which carries the plasmid-encoded dctABD operon was used in tube assays. It was found that the specific induction of Dct system oc-curred only at a certain depth under the surface of M63- 0.6% agar media, suggesting that Dct system could respond to oxygen concentration during succinate-induced expression. Furthermore, when measured at different oxygen concentra-tions, the highest expression level was observed at oxygen concentration of 2%. Thus, we predict that in addition to dicarboxylates, the induction of Dct system may also regu-lated by oxygen concentration.

关键词：黄香草木犀根瘤菌氧浓度 Dct系统

A Stable, Wideband Tunable, Near Transform-Limited, Graphene- Mode-Locked, Ultrafast Laser

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Nano Research 2010年第9期3卷 653-660页

作者： Zhipei Sun Daniel Popa Tawfique Hasan Felice Torrisi Fengqiu Wang Edmund J.R.kelleher John c.Travers Valeria Nicolosi Andrea c.Ferrari Department of Engineering University of CambridgeCambridge CB30FAUK Physics Department Imperial CollegeLondon SW72AZUK Department of Materials University of OxfordOxford OX13PHUK

We report an ultrafast laser mode-locked with a graphene saturable *** linear dispersions of the Dirac electrons in graphene enable wideband *** get-1 ps pulses,tunable between 1525 and 1559 nm,with stable mode-lockin... 详细信息

关键词： Graphene saturable absorber mode-locking fiber laser

Dietary intake in patients with chronic pancreatitis:A systematic review and meta-analysis

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World Journal of Gastroenterology 2021年第34期27卷 5775-5792页

作者： Qurat Ul Ain Yasir Bashir Linda kelleher David M Bourne Suzanne M Egan Jean McMahon Laura Keaskin Oonagh M Griffin Kevin c conlon Sinead N Duggan Professorial Surgical Unit Department of SurgeryTrinity College DublinDublin 24 D24 NR0AIreland Department of Nutrition and Dietetics Tallaght University HospitalDublin 24 D24 NR0AIreland Department of Newcastle Nutrition Freeman HospitalNewcastle Upon Tyne NE77DNUnited Kingdom Library and Information Services Tallaght Tallaght University HospitalDublin 24 D24 NR0AIreland Department of Nutrition and Dietetics St.Vincent’s University HospitalDublin 4 D04 T6F4Ireland

BAcKGROUND A progressive reduction in the secretion of pancreatic enzymes in patients with chronic pancreatitis(cP)results in malabsorption and ultimate ***,the pathogenesis of malnutrition is multifactorial and other factors such as chronic inflammation,alcohol excess and poor dietary intake all *** may restrict their dietary intake due to poor appetite or to avoid gastrointestinal symptoms and abdominal *** up to half of patients with chronic pancreatitis are reportedly malnourished,the dietary intake of patients with cP is relatively understudied and has not been systematically reviewed to *** To perform a systematic review and meta-analysis of the dietary intakes of patients with cP compared to healthy controls,and to compare the dietary intake of patients with alcohol-related cP and non-alcohol-related *** A systematic literature search was performed using EMBASE,MEDLINE,and cochrane review on studies published between 1946 and August 30th,*** subjects with a diagnosis of cP who had undergone dietary assessment were included in the systematic review(qualitative analysis).Studies on patients with other pancreatic diseases or who had undergone pancreatic surgery were not *** comparing the dietary intake of patients with cP to that of healthy controls were included in the meta-analysis(quantitative analysis).Metaanalysis was performed using Review Manager *** Ottawa Scale(NOS)was used to assess quality of *** Of 6715 studies retrieved in the search,23 were eligible for qualitative analysis while 12 were eligible for quantitative *** the meta-analysis,the total energy(calorie)intake of patients with cP was similar to that of healthy controls[mean difference(MD):171.3;95%confidence interval(cI):-226.01,568.5;P=0.4],however patients with cP consumed significantly fewer non-alcohol calories than controls[MD:-694.1;95%cI:-1256.1,(-132.1);P=0.02].cP patients consumed m

关键词： Systematic review Meta-analysis chronic pancreatitis Dietary intake Undernutrition Alcohol-related chronic pancreatitis

Solution processed MoS2-PVA composite for subbandgap mode-locking of a wideband tunable ultrafast Er：fiber laser

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Nano Research 2015年第5期8卷 1522-1534页

作者： Meng Zhang Richard c. T. Howe Robert I. Woodward Edmund J. R. kelleher Felice Torrisi Guohua Hu Sergei V. Popov J. Roy Taylor Tawfique Hasan Femtosecond Optics Group Blackett Laboratory Prince Consort Road Imperial College London London SW7 2AZ UK cambridge Graphene centre University of Cambridge Cambridge CB3 OFA UK

We fabricate a free-standing few-layer molybdenum disulfide （MoS2）-polymer composite by liquid phase exfoliation of chemically pristine MoS2 crystals and use this to demonstrate a wideband tunable, ultrafast mode-locked fiber laser. Stable, picosecond pulses, tunable from 1,535 nm to 1,565 nm, are generated, corresponding to photon energies below the MoS2 material bandgap. These results contribute to the growing body of work studying the nonlinear optical properties of transition metal dichalcogenides that present new opportunities for ultrafast photonic applications.

关键词： molybdenum disulfide two-dimensional materials liquid phase exfoliation polymer composites saturable absorbers ultrafast lasers

Few-layer MoS2 saturable absorbers for short-pulse laser technology: current status and future perspectives [Invited]

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Photonics Research 2015年第2期3卷 30-42页

作者： R.I.Woodward R.c.T.Howe G.Hu F.Torrisi M.Zhang T.Hasan E.J.R.kelleher Femtosecond Optics Group Department of Physics Imperial College London cambridge Graphene centre University of Cambridge

Few-layer molybdenum disulfide（MoS2） is emerging as a promising quasi-two-dimensional material for photonics and optoelectronics, further extending the library of suitable layered nanomaterials with exceptional optical properties for use in saturable absorber devices that enable short-pulse generation in laser systems. In this work, we catalog and review the nonlinear optical properties of few-layer MoS2, summarize recent progress in processing and integration into saturable absorber devices, and comment on the current status and future perspectives of MoS2-based pulsed lasers.

关键词： Mo current status and future perspectives Invited Few-layer MoS2 saturable absorbers for short-pulse laser technology

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对各种程度近视眼施行激光原位角膜磨镶术的5年随访

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世界核心医学期刊文摘(眼科学分册) 2006年第4期 23-24页

作者： O’Doherty M. O’Keeffe M. kelleher c. 桑延智 Prof. Mater Private Hospital Eccles Street Dublin 7 Ireland

Aims: To assess the long term refractive and visual outcome of patients who have laser in situ keratomileusis (LASIK) surgery. Methods: This was a retrospective study of visual and refractive outcome of patients who had LASIK surgery performed in 1998 and 1999. All levels of myopia were included in the study. 49 patients attended for follow up. The main outcome measures were safety, predictability, efficacy, and stability. Postoperative complications and aberrations were also recorded. The mean preoperative spherical equivalent was-4.85. Results: At 2 months postoperatively 67%of eyes were within plus or minus 0.5D of attempted correction with 81%within plus or minus 1.0D. At 5 years postoperatively 60%of eyes were within plus or minus 0.5D of attempted correction with 83%within plus or minus 1.0D. 88%of eyes had a vision of 6/12 or better at 2 months compared to 89%of eyes at 5 years. Best spectacle corrected visual acuity (BScVA) was unchanged or improved in 51%. No eye lost more than one line of BScVA. Overall, there was regression towards myopia with a mean change in refraction of-0.5D over the 5 years. As expected, severely myopic patients regressed more with a mean change of-1.06D. However, there was a high level of patient satisfaction with the surgery. conclusion: LASIK surgery offers predictable results in terms of refractive and visual outcome with mild regression in refraction over time.

关键词：激光原位角膜磨镶术近视手术屈光不正屈光回退 LASIK 程度

A Depth Resolved Insight into Benzoyl coA Reductase and Benzoate Dioxygenase Gene copy Numbers within a Marine Sediment Associated with Methane Seepage

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Open Journal of Marine Science 2013年第4期3卷 175-181页

作者： Paul V. Flanagan Brian P. kelleher Shane S. O’Reilly Michal T. Szpak Xavier Monteys Paul P. Kelly Anna N. Kulakova Leonid A. Kulakov christopher c. R. Allen Geological Survey of Ireland Beggar’s Bush Dublin Ireland School of Biological Sciences Queen’s University Belfast Belfast UK School of chemical Sciences Dublin City University Dublin Ireland

A marine sediment core obtained from a methane seepage site off the northern coast of Irelandwas analysed, at 3 depths, for catabolic genes associated with the aerobic and anaerobic degradation of aromatic compounds. catabolic gene copy numbers varied through the core peaking at 2.1 meters below sediment surface (mbsf)-just above the sulphate boundary. Beyond the sulphate boundary gene copy numbers fell considerably, suggesting the boundary may be a critical factor in the degradation of aromatic compounds within marine sediments. At the 2.1 mbsf depth our data also suggest that known benzoyl coA reductase utilizing bacteria are readily detectable.

关键词： Aromatic compounds qPcR bcr bdo

遗传性血色病进行缺铁治疗后,二价金属离子转运体1(DMT1)增加,而铁调节基因1(IREG1)和HFE基因mRNA表达不增加

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世界核心医学期刊文摘（胃肠病学分册） 2005年第1期1卷 44-45页

作者： kelleher T. Ryan E. Barrett S. J. crowe 马卉 centre for Liver Disease Mater Misericordiae Univ. HospitalDublin 7 Ireland

Background and aims: While upregulation of divalent metal transporter 1 (DMT1) and iron regulated gene 1 (IREG1)within duodenal enterocytes is reported in patients with hereditary haemochromatosis (HH), these findings are controversial. Furthermore,the effect of HFE, the gene mutated in HH, on expression of these molecules is unclear. This study examines duodenal expression of these three molecules in HH patients(prior to and following phlebotomy), in patients with iron deficiency (ID), and in controls. Methods: DMT1, IREG1, and HFE mRNA were measured in duodenal tissue of c282Y homozygous HH patients, in ID patients negative for the c282Y mutation with a serum ferritin concentration less than 20 μ g/l,and in controls negative for c282Y and H63D mutations with normal iron indices, using real time polymerase chain ***: DMT1 and IREG1 mRNA levels were not significantly different in non-phlebotomised (untreated) HH patients compared with controls. DMT1 expression was significantly increased in HH patients who had undergone phlebotomy therapy(treated) and in patients with ID compared with ***1 was significantly increased in ID patients relative to controls, and while IREG1 expression was 1.8-fold greater in treated HH patients, this was not statistically *** mRNA expression was not significantly different in any of the groups investigated relative to controls. conclusions:These findings demonstrate that untreated HH patients do not have increased duodenal DMT1 and IREG mRNA, but rather phlebotomy increases expression of these molecules, reflecting the effect of phlebotomy induced erythropoiesis. Finally, HFE appears to play a minor role in the regulation of iron absorption by the duodenal enterocyte.

关键词：遗传性血色病 DMT1 HFE基因mRNA IREG1 调节基因缺铁二价金属离子基因突变血清铁蛋白纯合子

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The induction of Sinorhizobium meliloti c4-dicarboxylate transport system （Dct） is regulated by oxygen concentration

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Science Bulletin 2005年第17期 77-81页

作者： WEN Jin1, NAN Beiyan1, fergal O’Gara2 & WANG Yiping1 1. National Laboratory of Protein Engineering and Plant Genetic Engi-neering, college of Life Sciences, Peking University, Beijing 100871, china 2. Microbiology Department, University college cork, National Univer-sity Ireland, cork, Ireland

关键词： Sinorhizobium meliloti Dct system oxygen concentration.