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Detailed characterization of kHz-rate laser-driven fusion at a thin liquid sheet with a neutron detection suite

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High Power Laser Science and Engineering 2024年第1期12卷 13-23页

作者： Benjamin m.Knight Connor m.Gautam Colton R.Stoner Bryan V.Egner Joseph R.Smith Chris m.Orban Juan J.manfredi Kyle D.Frische michael L.Dexter Enam A.Chowdhury Anil K.Patnaik Department of Engineering Physics Air Force Institute of TechnologyWPAFBOHUSA Physics Department Marietta CollegeMariettaOHUSA Department of Physics The Ohio State UniversityColumbusOHUSA Department of materials Science and Engineering and Department of Electrical and Computer ScienceThe Ohio State UniversityColumbusOHUSA Intense Energy Solutions LLCPlain CityOHUSA

We present detailed characterization of laser-driven fusion and neutron production(-10^(5)/second) using 8 mJ, 40 fs laser pulses on a thin(<1 μm) D_2O liquid sheet employing a measurement suite. At relativistic inte... 详细信息

We present detailed characterization of laser-driven fusion and neutron production(-10^(5)/second) using 8 mJ, 40 fs laser pulses on a thin(m) D_2O liquid sheet employing a measurement suite. At relativistic intensity(~ 5 × 10^(18)W/cm^(2))and high repetition rate(1 kHz), the system produces deuterium±deuterium(D-D) fusion, allowing for consistent neutron generation. Evidence of D-D fusion neutron production is verified by a measurement suite with three independent detection systems: an EJ-309 organic scintillator with pulse-shape discrimination, a ~3He proportional counter and a set of 36 bubble detectors. Time-of-flight analysis of the scintillator data shows the energy of the produced neutrons to be consistent with 2.45 meV. Particle-in-cell simulations using the WarpX code support significant neutron production from D-D fusion events in the laser±target interaction region. This high-repetition-rate laser-driven neutron source could provide a low-cost, on-demand test bed for radiation hardening and imaging applications.

关键词： high-repetition-rate laser-driven fusion laser-plasma interaction liquid target neutron detectors

Does the mcNeill Alexander model accurately predict maximum walking speed in novice and experienced race walkers？

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Journal of Sport and Health Science 2018年第3期7卷 372-377页

作者： andrew J.Harrison Patrick G.molloy Laura-Anne m.Furlong Department of Physical Education and Sport Sciences University of LimerickCastletroyLimerick V94 T9PXIreland School of Sport Exercise and Health Sciences Loughborough UniversityEpinalWayLoughboroughLeicestershire LEll 3TUUK

Background:mathematical models propose leg length as a limiting factor in determining the maximum walking *** study evaluated the effectiveness of a leg length-based model in predicting maximum walking velocity in an applied race walking situation,by comparing experienced and novice race walkers during conditions where strictly no flight time(FT)was permitted and in simulated competition conditions(i.e.,FTms).methods:Thirty-four participants(18 experienced and l6 novice race walkers)were recruited for this *** Optojump Next system(8 m)was used to determine walking velocity,step frequency,step length,ground contact time,and FT during race walking over a range of *** were made between novice and experienced participants in predicted maximum velocity and actual velocities achieved with no flight and velocities with FTmaximum velocity to predicted ***:In novices,no significant difference was found between predicted and maximum walking speeds without FT but there was a small 5.8%gain in maximum speed when FT≤40 *** experienced race walkers,there was a significant reduction in maximum walking speed compared with predicted maximum(pmaximum walking speed with FTmaximal walking velocity in novice walkers but not a good predictor of maximum walking speed in well-trained walkers who appear to have optimised their walking technique to make use of non-visible flight periods of less than 40 *** gain in velocity above predicted maximum may be a useful index of race walking proficiency.

关键词： Biomechanics Gait mathematical modelling Race walking Sports technique Technique development

Petrogenesis of middle Triassic Volcaniclastic Rocks from Balochistan,Pakistan:Implications for the Break-Up of Gondwanaland

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Journal of Earth Science 2017年第2期28卷 218-228页

作者： Rehanul Haq Siddiqui m.Qasim Jan m.Ishaq Kakar andrew C.Kerr Abdul Salam Khan Ehsanullah Kakar Balochistan University of Information Technology Engineering and Management Seiences Quetta 87300 Pakistan National Centre of Excellence in Geology University of Peshawar Pakistan & COMSTECH Islamabad 44000 Pakistan Centre of Excellence in mineralogy University of Balochistan Quetta 87300 Pakistan School of Earth and Ocean Sciences Cardiff University Main Building Park Place Cardiff Wales CF 10 3AT UK

Basaltic volcanic conglomerates near the Wulgai village in Balochistan occur in the undivided sedimentary rock unit of the Bagh complex which is the mélange zone beneath the muslim Bagh ophiolite. The presence of middle Triassic grey radiolarian chert within the upper and lower horizon of the conglomerates suggests that the lavas, from which these conglomerates were principally derived, were eroded and re-deposited in the middle Triassic. The Wulgai conglomerate contains several textural and mineralogical varieties of volcanic rocks, such as porphyritic, glomerophyric, intersertal and vitrophyric basalts. The main minerals identified in these samples are augite, olivine, plagioclase（An35–78） leucite and nosean, with apatite ilmenite, magnetite and hematite occurring as accessory minerals. These rocks are mildly to strongly-alkaline with low mg~# and low Cr, Ni and Co contents suggesting that their parent magma had undergone considerable fractionation prior to eruption. Trace element-enriched mantle-normalized patterns with marked positive Nb anomalies are consistent with 10%–15% melting of an enriched mantle source in a within-plate tectonic setting. It is proposed that this middle Triassic intra-plate volcanism may represent mantle plume-derived melts related to the Late Triassic rifting of micro-continental blocks（including Afghan, Iran, Karakorum and Lhasa） from the northern margin of Gondwana.

关键词： middle Triassic Wulgai volcaniclastics juvenile Ceno-Tethys

Environmentally relevant concentrations of aminopolycarboxylate chelating agents mobilize Cd from humic acid

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Journal of Environmental Sciences 2017年第7期29卷 249-257页

作者： Ashley E.North Sophia Sarpong-Kumankomah andrew R.Bellavie Wade m.White Jürgen Gailer Department of Chemistry and Environmental Science Program University of Calgary2500 University Drive NWCalgaryAB T2N 1N4Canada

Although Cd is a pollutant of public health relevance,many dietary sources from which it can be absorbed into human tissues remain *** it is well established that the biogeochemical cycle of Cd involves its complexation with environment-derived ligands（e.g.,humic acids,HAs） and anthropogenic ones（e.g.,chelating agents,CAs）,the interaction of Cd with both of these ligands is less well *** gain insight,a HA–Cd complex was injected on a size-exclusion chromatography（SEC） column coupled on-line with a flame atomic absorption spectrometer（FAAS） using 10 mmol/L Tris buffer（pH 8.0） as the mobile *** approach allowed us to observe the intact HA–Cd complex and the retention behavior of Cd as a function of 2–20 μmol/L concentrations of ethylenediaminetetraacetic acid（EDTA）,diethylenetriaminepentaacetic acid（DTPA） or methylglycinediacetic acid（mGDA） that were added to the mobile *** increase of the retention time of Cd was indicative of a partial or complete abstraction of Cd from *** results revealed that all CAs abstracted Cd from the HA–Cd complex at concentrations of 5 μmol/L,while mGDA and DTPA were effective at 2 μmol/*** bioavailability of some of the on-column formed CA–Cd complexes explains the previously reported increased accumulation of Cd in periphyton in the ecosystem downstream of wastewater treatment *** addition,our results imply that the use of effluents which contain CAs and Cd for the irrigation of food crops can introduce Cd into the food supply and compromise food safety.

关键词： Cadmium Humic acid Chelating agents EDTA DTPA mGDA Bioavailability

The Effect of Gelatin on the Preparation of Silica Coated Iron Particles

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Chemical Research in Chinese Universities 2000年第3期16卷 223-229页

作者： WANG Gui hua andrew Harrison Department of Chemistry Shanghai Normal UniversityShanghai 200234P.R.China Department of Chemistry The University of EdinburghEdinburghEH93JJUK

A method is described for coating fine iron particles(~1 μm) with a uniform silica layer, produced by the hydrolysis of tetraethyl orthosilicate. The presence of a small amount of gelatin on the surface of the iron particles facilitates this process. The X ray photoelectron measurements indicated that the gelatin interacted with the surface of the iron particles by means of both nitrogen(in —NH 2 groups) and oxygen(in —COOH groups) and then bound to the silica. The silica coating increases the resistance of the iron particles to oxidation on heating in air, which makes the temperature at which an observable oxidization occurs from 330 ℃ to 400 ℃ raised.

关键词： Fine iron particles Silica coating Gelatin

Transposable elements at the center of the crossroads between embryogenesis, embryonic stem cells, reprogramming,and long non-coding RNAs

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Science Bulletin 2015年第20期60卷 1722-1733页

作者： andrew Paul Hutchins Duanqing Pei Key Laboratory of Regenerative Biology South China Institute for Stem Cell Biology and Regenerative Medicine Guangzhou Institutes of Biomedicine and Health Chinese Academy of Sciences Guangdong Provincial Key Laboratory of Stem Cell and Regenerative medicine South China Institute for Stem Cell Biology and Regenerative Medicine Guangzhou Institutes of Biomedicine and Health Chinese Academy of Sciences Guangzhou Branch of the Supercomputing Center of Chinese Academy of Sciences South China Institute for Stem Cell Biology and Regenerative Medicine Guangzhou Institutes of Biomedicine and Health Chinese Academy of Sciences

Transposable elements(TEs) are mobile genomic sequences of DNA capable of autonomous and nonautonomous duplication. TEs have been highly successful,and nearly half of the human genome now consists of various families of TEs. Originally thought to be non-functional,these elements have been co-opted by animal genomes to perform a variety of physiological functions ranging from TE-derived proteins acting directly in normal biological functions, to innovations in transcription factor logic and influence on epigenetic control of gene expression. During embryonic development, when the genome is epigenetically reprogrammed and DNA-demethylated, TEs are released from repression and show embryonic stage-specific expression, and in human and mouse embryos, intact TEderived endogenous viral particles can even be detected. Asimilar process occurs during the reprogramming of somatic cells to pluripotent cells: When the somatic DNA is demethylated, TEs are released from repression. In embryonic stem cells(ESCs), where DNA is hypomethylated, an elaborate system of epigenetic control is employed to suppress TEs, a system that often overlaps with normal epigenetic control of ESC gene expression. Finally, many long non-coding RNAs(lnc RNAs) involved in normal ESC function and those assisting or impairing reprogramming contain multiple TEs in their RNA. These TEs may act as regulatory units to recruit RNA-binding proteins and epigenetic modifiers. This review covers how TEs are interlinked with the epigenetic machinery and lnc RNAs, and how these links influence each other to modulate aspects of ESCs,embryogenesis, and somatic cell reprogramming.

关键词： Transposable elements Endogenousretroviruses Embryonic stem cells lncRNA Reprogramming Pluripotency

Comparative effectiveness of i-SCAN^(Tm) and high-definition white light characterizing small colonic polyps

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World Journal of Gastroenterology 2012年第41期18卷 5905-5911页

作者： Johanna L Chan Li Lin michael Feiler andrew I Wolf Diana m Cardona Ziad F Gellad Department of medicine Duke University Medical CenterDurham NC 27705 United States Duke Clinical Research Institute DurhamNC 27705 United States Department of Pathology Duke UniversityMedical Center Durham NC 27705 United States Durham VA medical Center Durham NC 27705United States

AIm： To evaluate accuracy of in vivo diagnosis of ad- enomatous vs non-adenomatous polyps using/-SCAN digital chromoendoscopy compared with high-definition white light. mETHODS： This is a single-center comparative effec- tiveness pilot study. Polyps （n = 103） from 75 average- risk adult outpatients undergoing screening or surveil- lance colonoscopy between December 1, 2010 and April 1, 2011 were evaluated by two participating en- doscopists in an academic outpatient endoscopy center. Polyps were evaluated both with high-definition white light and with/-SCAN to make an/n vivo prediction of adenomatous vs non-adenomatous pathology. We de- termined diagnostic characteristics of/-SCAN and high- definition white light, including sensitivity, specificity, and accuracy, with regards to identifying adenomatous vs non-adenomatous polyps. Histopathologic diagnosis was the gold standard comparison. RESULTS： One hundred and three small polyps, de- tected from forty-three patients, were included in the analysis. The average size of the polyps evaluated in the analysis was 3.7 mm （SD 1.3 mm, range 2 mm to 8 mm）. Formal histopathology revealed that 54/103 （52.4%） were adenomas, 26/103 （25.2%） were hyper- plastic, and 23/103 （22.3%） were other diagnoses in- clude ＂lymphoid aggregates＂, ＂non-specific colitis,＂ and ＂no pathologic diagnosis.＂ Overall, the combined accu- racy of endoscopists for predicting adenomas was iden- tical between/-SCAN （71.8%, 95%CI： 62.1%-80.3%） and high-definition white light （71.8%, 95%CI： 62.1%-80.3%）. However, the accuracy of each endosco- pist differed substantially, where endoscopist A demon- strated 63.0% overall accuracy （95%CI： 50.9%-74.0%） as compared with endoscopist B demonstrating 93.3% overall accuracy （95%CI： 77.9%-99.2%）, irrespective of imaging modality. Neither endoscopist demonstrated a significant learning effect with i-SCAN during the study. Though endoscopist A increased accuracy using/-SCAN from 59% （95%CI： 42.1%-74.4%） in the first hal

关键词： Colonoscopy Adenoma Virtual chromoendoscopy Colonic polyps Comparative effectiveness

Humus-Rich Compost Increases Lettuce Growth, Nutrient Uptake, mycorrhizal Colonisation, and Soil Fertility

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Pedosphere 2019年第2期29卷 170-179页

作者： Zakaria m.SOLAImAN Hongjun YANG Deb ARCHDEACON Orna TIPPETT michaela TIBI andrew S.WHITELEY SoilsWest UWA School of Agriculture and Environment and the UWA Institute of Agriculture Faculty of Science The University of Western Australia College of Resources and Environment Southwest University C-Wise

Sandy soils, typical of Australia's west, either have little or no habitat protection for microbes including arbuscular mycorrhizal(Am) fungi, which are essential for nutrient cycling. To minimize this problem, the application of organic matter, such as humus-rich composts, is necessary during vegetable crop production. This study aimed at determining the effects of humus-rich composts on either indigenous or inoculated Am fungal colonisation in roots, lettuce(Lactuca sativa L. var. Quechua) growth, and soil fertility improvement. Four different humus-rich composts with varying humus contents were applied at the same standard rate to lettuce grown under glasshouse conditions for 10 weeks after sowing and compared with two low-humus composts and non-amended soil(control). Humus-rich composts significantly increased lettuce shoot growth, root growth, and Am fungal colonisation in roots. Humus contents in the composts were also correlated with lettuce shoot and root growth. Soil dissolved organic carbon, microbial biomass carbon, and fertility were increased with the application of humus-rich composts. These humus-rich composts, especially the compost of higher humic acid with and without Am inoculation, might have a significant role in sustainable vegetable production, for example lettuce growth. Overall, the results indicate that supplementation with humus-rich compost is highly beneficial to enhance soil fertility and potentially maintain the sustainability of vegetable production.

关键词： arbuscular mycorrhizal fungi humus nitrogen phosphorus vegetable production

Efficient Silencing of Endogenous microRNAs Using Artificial microRNAs in Arabidopsis thaliana

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molecular Plant 2011年第1期4卷 157-170页

作者： andrew L. Eamens Claire Agius Nell A. Smith Peter m. Waterhouse ming-Bo Wang CSIRO Plant Industry GPO Box 1600 Canberra ACT 2601 Australia School of molecular Bioscience University of Sydney Sydney NSW 2006 Australia

We report here that the expression of endogenous microRNAs （miRNAs） can be efficiently silenced in Arabi- dopsis thaliana （Arabidopsis） using artificial miRNA （amiRNA） technology. We demonstrate that an amiRNA designed to target a mature miRNA directs silencing against all miRNA family members, whereas an amiRNA designed to target the stem-loop region of a miRNA precursor transcript directs silencing against only the individual family member targeted. Furthermore, our results indicate that amiRNAs targeting both the mature miRNA and stem-loop sequence direct RNA silencing through cleavage of the miRNA precursor transcript, which presumably occurs in the nucleus of a plant cell during the initial stages of miRNA biogenesis. This suggests that small RNA （sRNA）-guided RNA cleavage in plants occurs not only in the cytoplasm, but also in the nucleus. many plant miRNA gene families have been identified via sequencing and bio- informatic analysis, but, to date, only a small tranche of these have been functionally characterized due to a lack of ef- fective forward or reverse genetic tools. Our findings therefore provide a new and powerful reverse-genetic tool for the analysis of miRNA function in plants.

关键词： microRNA artificial microRNA RNA silencing.