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Efficient above-band-gap light emission in germanium

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chinese Optics Letters 2009年第4期7卷 271-273页

作者： kenneth E.Lee Eugene A.Fitzgerald Lionel c.Kimerling Jurgen Michel Department of Materials Science and Engineering Microphotonics CenterMassachusetts Institute of Technology

We report an above-band-gap radiative transition in the photoluminescence spectra of single crystalline Ge in the temperature range of 20-296 K. The temperature-independence of the peak position at -0.74 eV is remarkably different from the behavior of direct and indirect gap transitions in Ge. This transition is observed in n-type, p-type, and intrinsic single crystal Ge alike, and its intensity decreases with the increase of temperature with a small activation energy of 56 meV. Some aspects of the transition are analogous to iii-V semiconductors with dilute nitrogen doping, which suggests that the origin could be related to an isoelectronic defect.

关键词： Activation energy Germanium Photoluminescence Semiconductor doping Single crystals

Luminescent cyclometalated iridium(Ⅲ) dipyridoquinoxaline indole complexes as biological probes

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Science china chemistry 2010年第10期53卷 2091-2098页

作者： LO kenneth Kam-Wing LEUNG Arthur Ho-Hon Department of Biology and chemistry City University of Hong Kong

Four luminescent cyclometalated iridium(Ⅲ) dipyridoquinoxaline complexes appended with an indole moiety [Ir(N^c)2(N^N)] (PF6) (HN^c = 2-phenylpyridine, Hppy; N^N = 2-(N-(2-(indole-3-acetamido)ethyl)aminocarbonyl)dipyrido[3,2-f:2′,3′-h]quinox- aline, dpqc2indole (1a), N^N = 2-(N-(6-(indole-3-acetamido)hexyl)aminocarbonyl)dipyrido[3,2-f:2′,3′-h]quinoxaline, dpqc6indole (1b); HN^c = 7,8-benzoquinoline, Hbzq, N^N = dpqc2indole (2a), N^N = dpqc6indole (2b)) have been synthesized and characterized. Upon irradiation, all the complexes displayed moderately intense and long-lived luminescence under ambient condi-tions and in 77 K glass. On the basis of the photophysical data, the emission of the complexes has been assigned to an excited state of triplet metal-to-ligand charge-transfer (3MLcT) ((dπ(Ir)→π*(N^N)) character. cyclic voltammetric studies revealed indole-based and iridium-based oxidations at ca. +1.10 V and +1.24 V vs. ScE, respectively, and ligand-based reductions at ca. -1.07 to-2.29 V vs. ScE. The interactions of the complexes with an indole-binding protein, bovine serum albumin (BSA), have been examined by emission titrations.

关键词： binding indole iridium luminescence probes

Longer term impact of cigarette package warnings in Australia compared with the United Kingdom and canada

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Longer term impact of cigarette package warnings in Australi...

Elevated temperature intensity,timing,and duration of exposure affect soybean internode elongation,mainstem node number,and pod number per plant

第17届全国控制吸烟学术研讨会

作者： Lin Li Ron Borland Hua Yong kenneth M.cummings James F.Thrasher Sara c.Hitchman Geoffrey T.Fong David Hammond Maansi Bansal-Travers Nigel Gray Fellowship Group Cancer Council Victoria Melbourne Victoria 3004 Australia Hollings cancer center Medical University of South Carolina Charleston SC 29425 USA Department of Health Promotion Education &Behavior Arnold School of Public Health University of S Institute of Psychiatry King's College Landon London SE5 8BB UK Department of Psychology University of Waterloo Waterloo Ontario N2L3G1 Canada Ontario Institute School of Public Health and Health Systems University of Waterloo Waterloo Ontario N2L 3G1 Canad Department of Health Behavior Roswell Park Cancer Institute Buffalo NY 14263 USA

This study examines the effects of different cigarette package warnings in Australia, canada and the United Kingdom up to 5 years postimplementation. The data came from the International Tobacco control *** included salience of warnings, cognitive responses, forgoing cigarettes and avoiding warnings. Although salience of the UK warnings was higher than the Australian and canadian pictorial warnings, this did not lead to greater levels of cognitive reactions, forgoing or *** was no difference in ratings between the Australian and UK warnings for cognitive responses and forgoing, but the canadian warnings were responded to more strongly. Avoidance of the Australian warnings was greater than to UK ones, but less than to the canadian warnings. The impact of warnings declined over time in all three countries. Declines were comparable between Australia and the United Kingdom on all measures except avoiding, where Australia had a greater rate of decline;and for salience where the decline was slower in canada. Having two rotating sets of warnings does not appear to reduce wear-out over a single set of *** size may be more important than warning type in preventing wear-out, although both probably contribute interactively.

关键词： Longer term impact of cigarette package warnings in Australia compared with the United Kingdom and canada

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The crop Journal 2018年第2期6卷 148-161页

作者： Leon Hartwell Allen Jr. Lingxiao Zhang kenneth J.Boote Bernard A.Hauser U.S.Department of Agriculture-Agricultural Research Service GainesvilleFL 32608USA Department of Agronomy University of FloridaGainesvilleFL 32611USA Department of Biology University of FloridaGainesvilleFL 32611USA

A study was conducted in four compartments of a polycarbonate greenhouse at Gainesville,FL, USA to investigate how a soybean(Glycine max L. Merr.) cultivar, Maverick(maturity group iii, indeterminate), responded to three elevated temperatures, ELT,(day/night of 34/26 °c, 38/30 °c, and 42/34 °c) in comparison to a control growth temperature(30/22 °c).carbon dioxide(cO_2) concentration was maintained at 700 μmol mol^(-1) in each compartment by a processor controlled air-sampling and cO_2-injection system. Three sequential experiments were conducted at different times of year(summer, autumn, and early spring)to investigate the effect of intensity, timing, and duration of ELT on soybean node number,internode elongation, mainstem length, and number of pods set per plant. At the control temperature, the soybean plants grown in the polycarbonate greenhouse were taller than field-grown plants. When plants were grown under continuous ELT applied soon after sowing or at initial flowering, the number of nodes increased with increasing ELT intensity,whereas the length of individual internodes decreased. When ELT treatment was applied during the beginning of flowering stage(R1–R2) or earlier, more nodes were produced and the length of affected internodes was decreased. When the ELT was imposed later at reproductive stage R5+ just before the beginning of seed filling, effects on node numbers and internode lengths were negligible. Short-term(10-day) duration of ELT applied at four stages from V3 to R5+ did not significantly affect final mean numbers of nodes or mean mainstem lengths. Possible mechanisms of elevated temperature effects on soybean internode elongation and node number(internode number) are discussed. Total pod numbers per plant increased linearly with mainstem node numbers and mainstem ***, total pod numbers per plant were greatest at 34/26 °c rather than at the control temperature of 30/22 °c(and remained high at 38/30 °c). Mild increases in temperatu

关键词： Elevated temperature Internode elongation Node number Pod yield Soybean phenology

clinical efficacy of rosuvastatin in lipid management in chinese patients in Hong Kong

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chinese Medical Journal 2009年第23期122卷 2814-2819页

作者： Vivian W.Y. Lee T.S. chau Vice EH. Leung kenneth K.c. Lee Brian Tomlinson School of Pharmacy Faculty of Medicine The Chinese University of Hong Kong Hong Kong China Department of Medicine and Therapeutics The Chinese University of Hong Kong Hong Kong China

Background Rosuvastatin has been claimed to be more potent than other statins in its ability to lower the low-density lipoprotein （LDL） cholesterol levels. This study aimed to investigate the clinical efficacy of rosuvastatin in LDL cholesterol lowering therapy for new or switched hyperlipidaemic chinese patients. Methods This study was a retrospective one in patients who took rosuvastatin in the outpatient clinics of Prince of Wales Hospital during the period of July 1,2004 to June 30, 2005. The prescribing pattern, the utilization pattern and the side effect profile were recorded. Attainment of lipid goals for each patient was assessed according to the National cholesterol Education Program Adult Treatment Panel （NcEP ATP） iii guidelines. Results A total of 261 chinese patients （mean age （64.8±12） years; 55.6% male） were recruited into the study. The mean LDL-cholesterol level was （3.50±1.29） mmol/L prior to Rosuvastatin and （2.30±1.73） mmol/L after Rosuvastatin treatment （P 〈0.0001）. Rosuvastatin raised the LDL-cholesterol goal achievement rate from 28.0% to 74.3% in all patients combined （P 〈0.0001） and from 11.0% to 79.0% for statin naive patients （P 〈0.0001）. Approximately 4% of patients developed side effects including myalgia, elevated liver enzymes, and dizziness. conclusion Rosuvastatin was effective in improving LDL-cholesterol goal attainment and lowering LDL-cholesterol and triglyceride （TG） levels in either newly started or switched patients.

关键词： cholesterol rosuvastatin clinical efficacy

Breeding for drought tolerance in perennial ryegrass(Lolium perenne L.)and tall fescue(Lolium arundinaceum[Schreb.]Darbysh.)by exploring genotype by environment by management interactions

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Grassland Research 2023年第1期2卷 22-36页

作者： claudio c.Fernandes Filho Mario H.Murad Leite Andrade Jose A.Rodrigues Nunes Joseph Wipff Debra L.Hignight Esteban F.Rios Kevin Kenworthy kenneth Hignight Biology Department Institute of Natural SciencesUniversidade Federal de LavrasLavrasBrazil Agronomy Department University of FloridaGainesvilleFloridaUSA NexGen Plant Science center LLCAlbanyOregonUSA NexGen Turf Research LLCAlbanyOregonUSA

Background:Drought‐tolerant turfgrass cultivars are becoming more important each year as landscape irrigation practices are becoming more ***:In this study,we quantified the level of drought tolerance(DT)in perennial ryegrass and tall fescue genotypes across years under different mowing(MH)and fertility(FL)rates.A total of 48 ryegrass and 38 tall fescue genotypes were planted in 2011 at NexGen,Albany,*** trial was divided into three subtrials:(i)DT;(ii)MH and DT;and(iii)FL and ***:The results showed that there was significant genetic variance for most of the traits in both *** genotype×year interaction was predominantly simple,indicating small changes in genotype ranking for both *** MH improved DT in perennial ryegrass,whereas higher MH resulted in greater DT in tall *** both species,higher MH improved the population mean for turf *** FL inputs led to higher turf quality for both species,but it did not affect the DT ***:Using a selection index,six genotypes for perennial ryegrass and four for tall fescue were selected.

关键词： drought stress ryegrass tall fescue turf quality turfgrass breeding

Elevated temperature intensity, timing, and duration of exposure affect soybean internode elongation,mainstem node number, and pod number per plant

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