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Compact nano-void spectrometer based on a stable engineered scattering system

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Photonics Research 2022年第10期10卷 2328-2336页

作者： QI SUN PRZEmYSLAW FALAK TOm VETTENBURG timothy LEE DAVID BPHILLIPS GILBERTO BRAmBILLA mARTYNAS BERESNA Optoelectronics Research Centre University of SouthamptonSouthamptonSO171BJUK University of Dundee NethergateDundeeDD14HNUK University of Exeter ExeterEX44QLUK

Random scattering of light in disordered media can be used for highly sensitive speckle-based wavemeters and spectrometers. However, the multiple scattering events that fold long optical paths within a compact space also make such devices exceedingly sensitive to vibrations and small disturbances to the disordered media. Here, we show how scattering can be engineered so that it can be used for a compact computational spectrometer that is largely insensitive to environmental factors. We designed and fabricated a three-dimensional pseudo-random nano-void pattern with 62% scattering efficiency. The controlled amount of multiple scattering ensured a sufficiently long optical path for the target resolution of 100 pm, with optimal long-term stability. The 200-μm-thick scattering silica substrate was integrated in a compact assembly with a low-cost camera sensor. The target resolution was achieved for full spectrum measurements while single wavelengths could be determined with 50 pm resolution. Such tailored scattering systems can improve the trade-off among cost, size, stability, and spectral resolution in computational spectrometers.

关键词： stability disordered exceeding

Local hardening and asymmetric twin growth by twin-twin interactions in a mg alloy

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Journal of magnesium and Alloys 2023年第1期11卷 176-191页

作者： Krishna Yaddanapudi mariyappan Arul Kumar Jiaxiang Wang Xin Wang timothy J.Rupert Enrique J.Lavernia Julie m.Schoenung Irene J.Beyerlein Subhash mahajan Department of materials Science and Engineering University of CaliforniaDavisCA 95616USA materials Science and Technology Division Los Alamos National LaboratoryLos AlamosNM 87545USA Department of mechanical Engineering Materials DepartmentUniversity of CaliforniaSanta BarbaraCA 93106USA Department of materials Science and Engineering University of CaliforniaIrvineUSA materials Department University of CaliforniaSanta BarbaraCA 93106USA

In this study,the role of twin-twin interactions on the distributions of local defects(e.g.,dislocations)and stress fields in a magnesium alloy is investigated.A co-zone(1012)-(1012)tensile twin junction in a deformed mg-3wt.%Y alloy is analyzed using transmission electron microscopy(TEm).The results show that the morphology of the impinging(1012)twin is asymmetric,and the non-interacting boundary of the recipient(1012)twin is *** analysis of TEm images reveals that type-II pyramidal[1213](1212)dislocations concentrate in the vicinity of the twin-twin junction *** samedislocations are also observed inside the interacting twin domains along with a few ***dislocations emanating from the impinging(1012)twin boundary have edge character and are extended with faults parallel to the basal *** contrast,thedislocations connected to the recipient(1012)twin are predominantly screw orientation and ***-viscoplastic fast Fourier transform based crystal plasticity calculations are performed to rationalize the observed twin morphology and local dislocation *** model calculations suggest that the local stress fields generated at the junction site where the two twins meet are responsible for the experimentally observed concentration of*** calculated stress fields are asymmetric with respect to the junction site,explaining the observed asymmetric morphology of the impinging ***,these findings show strong effects of twin-twin interactions on the distribution of dislocations as well as the evolution of the twinned microstructure and as such,can help advance understanding of twinning in mg alloys and their effect on mechanical behavior.

关键词： Tensile twins Twin-twin intersections mg alloys Crystal plasticity TEm

Net ecosystem carbon exchange for Bermuda grass growing in mesocosms as affected by irrigation frequency

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Pedosphere 2022年第3期32卷 393-401页

作者： Yuan LI Gabriel *** timothy J.CLOUGH John E.HUNT David WHITEHEAD Department of Soil and Physical Sciences Lincoln UniversityLincoln 7647(New Zealand) manaaki Whenua-Landcare Research P.O.Box 69040Lincoln 7640(New Zealand) State Key Laboratory of Grassland Agro-ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730020(China) Soil Biology Group Wageningen University and ResearchP.O.Box 47Wageningen 6700 AA(The Netherlands)

Intensification of grazed grasslands following conversion from dryland to irrigated farming has the potential to alter ecosystem carbon(C)cycling and affect components of carbon dioxide(CO_(2))exchange that could lead to either net accumulation or loss of soil *** there are many studies on the effect of water availability on biomass production and soil C stocks,much less is known about the effect of the frequency of water inputs on the components of CO_(2)*** grew Bermuda grass(Cynodon dactylon L.)in mesocosms under irrigation frequencies of every day(I_(1) treatment,30 d),every two days(I_(2) treatment,12 d),every three days(I_(3) treatment,30 d),and every six days(I_(6) treatment,18 d,after I_(2) treatment).Rates of CO_(2)exchange for estimating net ecosystem CO_(2)exchange(F_(N)),ecosystem respiration(R_(E)),and soil respiration(R_(S))were measured,and gross C uptake by plants(F_(G))and respiration from leaves(R_(L))were calculated during two periods,1–12 and 13–30 d,of the 30-d *** the first 12 d,there were no significant differences in cumulative F_(N)(mean±standard deviation,61±30 g C m^(-2),n=4).During the subsequent 18 d,cumulative F_(N) decreased with decreasing irrigation frequency and increasing cumulative soil water deficit(W),with values of 70±22,60±16,and 18±12 g C m^(-2) for the I_(1),I_(3),and I_(6) treatments,*** were similar decreases in F_(G),R_(E),and R_(L) with increasing W,but differences in R_(S) were not *** of the C_(4) grass growing in a C_(3)-derived soil enabled partitioning of R_(S) into its autotrophic(R_(A))and heterotrophic(R_(H))components using a^(13)C natural abundance isotopic technique at the end of the experiment when differences in cumulative W between the treatments were the *** values of R_(H) and its percentage contributions to R_(S)(43%±8%,42%±8%,and 8%±5%for the I_(1),I_(3),and I_(6) treatments,respectively)suggested that R_(H) remained unaffected across a wide

关键词： ^(13)C natural abundance CO_(2)exchange N_(2)O emission soil heterotrophic respiration water deficit

Two haplotype-resolved genomes reveal important flower traits in bigleaf hydrangea(Hydrangea macrophylla)and insights into Asterid evolution

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Horticulture Research 2023年第12期10卷 45-57页

作者： Xingbo Wu Sheron A.Simpson Ramey C.Youngblood Xiaofen FLiu Brian E.Scheffler timothy A.Rinehart Lisa W.Alexander Amanda m.Hulse-Kemp Department of Environmental Horticulture Tropical Research and Education CenterUniversity of FloridaHomesteadFL 33031United States Genomics and Bioinformatics Research Unit USDA-ARSRaleighNC 27695United States Genomics and Bioinformatics Research Unit USDA-ARSStonevilleMS 38776United States Institute for Genomics Biocomputing and BiotechnologyMississippi State UniversityStarkvilleMS 39762United States Crop Production and Protection USDA-ARSBeltsvilleMD 20705United States Floral and Nursery Plants Research Unit U.S.National ArboretumUSDA-ARSMcMinnvilleTN 37110United States Department of Crop and Soil Sciences North Carolina State UniversityRaleighNC 27695United States

The Hydrangea genus belongs to the Hydrangeaceae family,in the Cornales order of flowering plants,which early diverged among the Asterids,and includes several species that are commonly used ornamental *** them,Hydrangea macrophylla is one of the most valuable species in the nursery trade,yet few genomic resources are available for this crop or closely related Asterid *** high-quality haplotype-resolved reference genomes of hydrangea cultivars‘Veitchii’and‘Endless Summer’[highest quality at 2.22 gigabase pairs(Gb),396 contigs,N5022.8 megabase pairs(mb)]were assembled and scaffolded into the expected 18 *** the newly developed high-quality reference genomes along with high-quality genomes of other related flowering plants,nuclear data were found to support a single divergence point in the Asterids clade where both the Cornales and Ericales diverged from the *** mapping with an F1 hybrid population demonstrated the power of linkage mapping combined with the new genomic resources to identify the gene for inflorescence shape,CYP78A5 located on chromosome 4,and a novel gene,BAm3 located on chromosome 17,for causing double *** developed in this study will not only help to accelerate hydrangea genetic improvement but also contribute to understanding the largest group of flowering plants,the Asterids.

关键词： Hydra traits resolved

A survey of sub-inhibitory concentrations of antibiotics in the environment

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Journal of Environmental Sciences 2021年第1期33卷 21-27页

作者： Louise K.m.Chow timothy m.Ghaly michael R.Gillings Department of Biological Sciences Macquarie UniversityNSW 2109Australia ARC Centre of Excellence in Synthetic Biology Macquarie UniversityNSW 2109Australia

Antibiotics are poorly metabolized,and can enter the environment via human waste streams,agricultural run-off and pharmaceutical *** consequently expect to see a concentration gradient of antibiotic compounds radiating from areas of human *** antibiotics should be thought of as pollutants,as they can accumulate,and have biological *** antibiotic pollutants can increase rates of mutation and lateral transfer events,and continue to exert selection pressure even at sub-inhibitory ***,we conducted a literature survey on environmental concentrations of *** collated 887 data points from 40 peer-reviewed *** then determined whether these concentrations were biologically relevant by comparing them to their minimum selective concentrations,usually defined as between 1/4 and 1/230 of the minimum inhibitory *** concentrations of antibiotics surveyed often fall into this *** general,the antibiotic concentrations recorded in aquatic and sediment samples were *** findings indicate that environmental concentrations of antibiotics are likely to be influencing microbial ecology,and to be driving the selection of antibiotic resistant bacteria.

关键词： Antimicrobial Pollution Evolution microorganism Environment Antibiotic resistance

Realising the Potential of Genomics for m. tuberculosis: A Silver Lining to the Pandemic?

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China CDC weekly 2022年第20期4卷 437-439页

作者： timothy m Walker Derrick W Crook Oxford University Clinical Research Unit Ho Chi Minh CityVietnam Nuffield Department of medicine University of Oxford OxfordUK

The impact of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)pandemic on tuberculosis has been ***,there were 1.4 million fewer patients receiving tuberculosis treatment in 2020,representing not a fall in the global case load but a failure to serve millions of patients with the disease(1–2).morbidity,mortality,and onward transmission are inevitable outcomes of such failure,setting the world back a decade of progress.

关键词： tuberculosis mortality acute

江南造山带东段赣东北蛇绿岩的形成时代:来自辉长岩LA-ICP-mS锆石U-Pb年龄的证据

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现代地质 2017年第4期31卷 697-704,745页

作者：蒋幸福彭松柏 kusky timothy 王璐邓浩王军鹏东华理工大学地球科学学院江西南昌330013 中国地质大学(武汉)地球科学学院湖北武汉430074 中国地质大学(武汉)地质过程与矿产资源国家重点实验室湖北武汉430074 中国地质大学(武汉)教育部长江三峡库区地质灾害研究中心湖北武汉430074

赣东北元古宙蛇绿岩位于江南造山带东段,主要由蛇纹石化超基性岩、堆晶岩、辉长岩、辉绿岩、低温高压蓝片岩以及斜长花岗岩组成。对赣东北蛇绿岩中辉长岩进行了LA-ICP-mS锆石U-Pb定年,获得^(207)Pb/^(206)Pb加权平均年龄值为(992±25)ma... 详细信息

赣东北元古宙蛇绿岩位于江南造山带东段,主要由蛇纹石化超基性岩、堆晶岩、辉长岩、辉绿岩、低温高压蓝片岩以及斜长花岗岩组成。对赣东北蛇绿岩中辉长岩进行了LA-ICP-mS锆石U-Pb定年,获得^(207)Pb/^(206)Pb加权平均年龄值为(992±25)ma(mSWD=1.19),以此代表该辉长岩的结晶年龄。这一年代学结果表明扬子陆块东南缘古洋盆在新元古代早期就已存在,但晚于扬子北缘中元古代晚期古洋盆(~1 120 ma),暗示扬子克拉通中—新元古代结晶基底的形成具有从西北往东南逐步拼贴的特征。

关键词：江南造山带赣东北蛇绿岩辉长岩锆石U-Pb定年新元古代早期

The Zunhua-Zanhuang Ophiolitic mélange: Traces of an Archean Suture in the North China Craton

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Acta Geologica Sinica(English Edition) 2015年第A2期89卷 37-38页

作者： kusky T.m LI J.H PLOAT A WANG Junpeng DENG Hao WANG Lu Center for Global Tectonics China University of Geosciences Wuhan 430074 China Department of Geology Peking University China Department of Earth and Environmental Sciences University of Windsor Ontario Canada

Sutures mark places once widely separated defined on the basis differences in the where oceans have closed and two terranes have collided. Sutures are of geological relationships, and geologic, structural, magmatic,

关键词： RESEARCH Suture zones (Structural geology) Orogenic belts Structural geology Ophiolites melanges (Petrology)

The BRICS and Beyond： Insights into Human Development/Security from ＂Global Governance＂？

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Fudan Journal of the Humanities and Social Sciences 2014年第3期7卷 381-394页

作者： timothy m. Shaw mcCormack Graduate School University of Massachusetts Boston 100 Morrissey BoulevardBoston MA 02125-3393 USA

The decade of the BRICS is leading to the reanalysis of global relations, encouraged by the simultaneous rise of emerging markets and decline of the eurozone PIIGS. But is the trajectory towards global reorder and/or disorder? Development like capitalisms and regionalisms is increasingly diverse: heterogeneous transnational networks best approached through a global studies frame? Together these factors impact the balance between developmental and fragile states in African as elsewhere. And there are debates about what is emerging: companies? economies? states? and/or societies? meanwhile, the “global” increasingly includes informal and illegal economies, especially TOC, including transnational Chinese mafias. Transnational governance continues to widen its scope to include airline and container alliances as well as a trio of commissions on drugs.

关键词：人类发展金砖治理安全地域主义资本主义跨国公司航空公司