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Directly modulated quantum dot lasers on silicon with a milliampere threshold and high temperature stability

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Photonics Research 2018年第8期6卷 776-781页

作者： YATING WAN DAISUKE INOUE DAEHWAN JUNG JUSTIN c.NORMAN cHEN SHANG arthur c.gossard JOHN E.BOWERS Institute for Energy Efficiency University of California Santa Barbara Institute of Innovative Research Tokyo Institute of Technology Materials Department University of California Santa Barbara Department of Electrical and computer Engineering University of California Santa Barbara

Microring lasers feature ultralow thresholds and inherent wavelength-division multiplexing functionalities, offering an attractive approach to miniaturizing photonics in a compact area. Here, we present static and dynamic properties of microring quantum dot lasers grown directly on exact(001) GaP/Si. Effectively, a single-mode operation was observed at 1.3 μm with modes at spectrally distant locations. High temperature stability with T_0~103 K has been achieved with a low threshold of 3 mA for microrings with an outer ring radius of 15 μm and a ring waveguide width of 4 μm. Small signal modulation responses were measured for the first time for the microrings directly grown on silicon, and a 3 dB bandwidth of 6.5 GHz was achieved for a larger ring with an outer ring radius of 50 μm and a ring waveguide width of 4 μm. The directly modulated microring laser,monolithically integrated on a silicon substrate, can incur minimal real estate cost while offering full photonic functionality.

关键词：微环激光器通讯技术发展现状技术创新

Probiotic supplementation decreases intestinal transit time: Meta-analysis of randomized controlled trials

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World Journal of Gastroenterology 2013年第29期19卷 4718-4725页

作者： Larry E Miller arthur c Ouwehand Miller Scientific consulting Inc. Arden NC 28704 United States DuPont Nutrition and Health FIN-02460 Kantvik Finland

AIM: To determine the efficacy of probiotic supplementation on intestinal transit time (ITT) and to identify factors that influence these outcomes. METHODS: A systematic review of randomized controlled trials (RcTs) of probiotic supplementation that measured ITT in adults was conducted by searching MEDLINE and EMBASE using relevant combinations. Main search limits included RcTs of probiotic supplementation in healthy or constipated adults that measured ITT. Study quality was assessed using the Jadad scale. A random effects meta-analysis was performed with standardized mean difference (SMD) of ITT between probiotic and control groups as the primary outcome. Meta-regression and subgroup analyses were conducted to examine the impact of moderator variables on ITT SMD. RESULTS: A total of 11 clinical trials with 13 treatment effects representing 464 subjects were included in this analysis. Probiotic supplementation was associated with decreased ITT in relation to controls, with an SMD of 0.40 (95%cI: 0.20-0.59, P constipation (r 2 = 39%, P = 0.01), higher mean age (r 2 = 27%, P = 0.03), and higher percentage of female subjects (r 2 = 23%, P ctive of decreased ITT with probiotics in meta-regression. Subgroup analyses demonstrated statistically greater reductions in ITT with probiotics in subjects with vs without constipation and in older vs younger subjects [both SMD: 0.59 (95%cI: 0.39-0.79) vs 0.17 (95%cI: -0.08-0.42), P = 0.01]. Medium to large treatment effects were identified with Bifidobacterium Lactis (B. lactis ) HN019 (SMD: 0.72, 95%cI: 0.27-1.18, P ctis DN-173 010 (SMD: 0.54, 95%cI: 0.15-0.94, P combination products yielded small treatment effects. cONcLUSION: Overall, short-term probiotic supplementation decreases ITT with consistently greater treatment effects identified in constipated or older adults and with certain probiotic strains.

关键词： constipation Gastrointestinal Intestinal transit time Meta-analysis Probiotics

The effects of human-generated sound on fish

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Integrative Zoology 2009年第1期4卷 43-52页

作者： arthur N.POPPER Mardi c.HASTINGS Department of Biology University of MarylandCollege ParkUSA Applied Research Laboratory The Pennsylvania State UniversityState CollegeUSA

There is growing international concern about the effects of human-generated sound on fish and other aquatic ***,because of a striking paucity of well-designed and controlled experimental data,very little is actually known about the effects of these sounds on *** suggest that human-generated sounds,even from very high intensity sources,might have no effect in some cases or might result in effects that range from small and temporary shifts in behavior all the way to immediate *** this point,however,it is nearly impossible to ex-trapolate from results with one sound source,one fish species,or even fish of one size to other sources,species,or fish *** present paper briefly discusses the potential effects of sound on fish,describes some of the more recent well-controlled experimental studies,and points out areas for future study that will be needed before a real understanding of the effects of sound on fish can be developed.

关键词： anthropogenic sound behavior hearing noise sound.

co_(6)Se_(8)(PEt_(3))_(6) superatoms as tunable chemical dopants for two-dimensional semiconductors

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npj computational Materials 2018年第1期4卷 373-378页

作者： arthur c.Reber Shiv N.Khanna Department of Physics Virginia Commonwealth UniversityRichmondVA 23284USA

Electronic,optoelectronic,and other functionalities of semiconductors are controlled by the nature and density of carriers,and the location of the Fermi *** strategies to tune these parameters holds the key to precise control over semiconductors *** propose that ligand exchange on superatoms can offer a systematic strategy to vary these *** demonstrate this by considering a WSe_(2) surface doped with ligated metal chalcogenide co_(6)Se_(8)(PEt_(3))_(6) *** superatoms are characterized by valence quantum states that can readily donate multiple *** find that the WSe_(2) support binds more strongly to the co_(6)Se_(8) cluster than the PEt3 ligand,so ligand exchange between the phosphine ligand and the WSe_(2) support is energetically *** metal chalcogenide superatoms serves as a donor that may transform the WSe_(2) p-type film into an ntype *** theoretical findings complement recent experiments where WSe_(2) films with supported co_(6)Se_(8)(PEt_(3))_(6) are indeed found to undergo a change in behavior from p-to *** further show that by replacing the PEt3 ligands by cO ligands,one can control the electronic character of the surface and deposited species.

关键词： properties. semiconductors holds

correcting for non-compliance when determining colonic transit time with radio-opaque markers

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World Journal of Gastroenterology 2017年第4期23卷 740-742页

作者： Alvin Ibarra Kaisa Olli arthur c Ouwehand DuPont Nutrition and Health 02460 KantvikFinland

The use of radio-opaque markers and abdominal X-ray is the standard method for determining colonic transit time(cTT). However, when there are deviations in the intake of these markers by participants in clinical trials it is desirable to improve observations by introducingcorrections, where possible. To date, there is no standard procedure to adjust for such deviations. This report proposes a series of alternatives based on possible scenarios for deviations from the intended intake of radio-opaque markers. The proposed method to correct for missed or delayed consumption of radioopaque markers can help to increase the accuracy of the cTT measurements in clinical trials.

关键词： colonic transit time Gastroenterology Gut transit time Radio-opaque marker X-ray

NumericalModeling of ElasticWave Propagation in a Fluid-Filled Borehole

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communications in computational Physics 2008年第1期3卷 33-51页

作者： arthur c.H.cheng Joakim O.Blanch cambridge GeoSciences 14090 Southwest FreewaySuite 300Sugar LandTX 77478USA Nexus GeoSciences 14090 Southwest FreewaySuite 240Sugar LandTX 77478USA previously at SensorWise Inc.2908 RodgerdaleHoustonTX 77042USA.

We review the methods of simulating elastic wave propagation in a *** considered two different approaches: a quasi-analytic approach using theDiscreteWavenumber SummationMethod, and the purely numerical Finite DifferenceMethod. We consider the special geometry of the borehole and discuss the problem incylindrical coordinates. We point out some numerical difficulties that are particularlyunique to this problem in cylindrical coordinates.

关键词： Acoustic borehole numerical modeling.

contemporary meta-analysis of short-term probiotic consumption on gastrointestinal transit

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World Journal of Gastroenterology 2016年第21期22卷 5122-5131页

作者： Larry E Miller Angela K Zimmermann arthur c Ouwehand Miller Scientific consulting Inc. Asheville NC 28803 United States DuPont Nutrition and Health FIN-02460 Kantvik Finland

AIM: To determine the efficacy of probiotic supplementation on intestinal transit time(ITT) in adults and to identify factors that influence these outcomes. METHODS: We conducted a systematic review of randomized controlled trials of probiotic supplementation that measured ITT in adults. Study quality was assessed using the Jadad scale. A random effects meta-analysis was performed with standardized mean difference(SMD) of ITT between probiotic and control groups as the primary outcome. Meta-regression and subgroup analyses examined the impact of moderator variables on SMD of ***: A total of 15 clinical trials with 17 treatment effects representing 675 subjects were included in this analysis. Probiotic supplementation was moderately efficacious in decreasing ITT compared to control, with an SMD of 0.38(95%cI: 0.23-0.53, P cally greater reductions in ITT with probiotics in subjects with vs without constipation(SMD: 0.57 vs 0.22, P constipation(R^2 = 38%, P centage of female subjects(R^2 = 26%, P = 0.02), and fewer probiotic strains(R^2 = 20%, P ctive of decreased ITT with probiotics in meta-regression. Medium to large treatment effects were identified with B. lactis HN019(SMD: 0.67, P ctis DN-173 010(SMD: 0.54, P c strains yielded negligible reductions in ITT relative to ***: Probiotic supplementation is moderately efficacious for reducing ITT in adults. Probiotics were most efficacious in constipated subjects, when evaluated in high-quality studies, and with certain probiotic strains.

关键词： constipation Gastrointestinal Intestinal transit time Meta-analysis Probiotics

Influence of a probiotic mixture on antibiotic induced microbiota disturbances

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World Journal of Gastroenterology 2014年第33期20卷 11878-11885页

作者： Sofia Forssten Malkanthi Evans Dale Wilson arthur c Ouwehand Active Nutrition DuPont Nutrition & Health 02460 Kantvik Finland KGK Synergize London ONN6A 5R8 Canada

AIM: To study the effect of probiotic consumption on the faecal microbiota during and after antibiotic exposure.

关键词： Probiotic Antibiotic treatment Amoxicillin/ clavulanate Microbiota Beta-lactamases Lactobacillus acidophilus Bifidobacterium lactis

Influence of growing location and cultivar on Rhyzopertha dominica （coleoptera： Bostrichidae） and Sitophilus oryzae （coleoptera： curculionidae） infestation of rough rice

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Insect Science 2007年第3期14卷 231-239页

作者： FRANK H. arthur RUSTY c. BAUTISTA TERRENcE J. SIEBENMORGEN USDA-ARS Grain Marketing and Production Research center Manhattan Kansas Department of Food Science University of Arkansas Fayetteville Arkansas USA

Long-grain rice cultivars cocodrie, Wells, and XP 723 grown in three locations （Hazen, MO; Essex and Newport, AR, USA）, and medium-grain rice cultivars Bengal and XP 713 grown in two locations （Jonesboro and Lodge corner, AR, USA）, were harvested and assayed for susceptibility to Rhyzopertha dominica （F.）（coleoptera： Bostrichidae）, the lesser grain borer, and Sitophilus oryzae （L.）（coleoptera： curculionidae）, the rice weevil, on rice held at 27℃, 57% and 75% relative humidity （RH）. Separate samples from the same harvest lots were also analyzed for the physical characteristics of brown rice yield, percentage whole kernels and kernel thickness. Progeny production and feeding damage of R. dominica were significantly different among long-grain cultivars within two of the three locations （P 〈 0.05）, but not for location or RH （P ≥ 0.05）, while progeny production of S. oryzae was different among cultivars, location, and RH （P 〈 0.05）. On medium-grain rice, both cultivar and location were significant for progeny production of R. dominica, but not RH, while cultivar and RH were significant for progeny production of S. oryzae, but not location. On both rice types, feeding damage of R. dominica followed the same trends and was always strongly positively correlated with progeny production （P 〈 0.05）, but for S. oryzae there were several instances in which progeny production was not correlated with feeding damage （P ≥ 0.05）. Physical characteristics of both rice types were statistically significant （P 〈 0.01） but actual numerical differences were extremely small, and were generally not correlated with progeny production of either species. Results indicate that the location in which a particular rice cultivar is grown, along with its characteristics, could affect susceptibility of the rice to R. dominica and S. oryzae.

关键词： rough rice cultivars stored-product insects Rhyzopertha dominica Sitophilus oryzae