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Geoscience Frontiers 2013年第2期4卷 167-183页

作者： David b.smith Steven M.smith john D.Horton U.S.Geological Survey.Denver Federal Center MS 973.DenverCO 80225USA

Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United *** earliest of these,here termed the ＇Shacklette＇ data set,was generated b. a U.S. Geological Survey（USGS） project conducted from 1961 to *** project used soil collected from a depth of ab.ut 20 cm as the sampling medium at 1323 sites throughout the conterminous *** national Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance（NUREHSSR） Program of the *** of Energy was conducted from 1975 to 1984 and collected either stream sediments,lake sediments,or soils at more than 378,000 sites in b.th the conterminous *** *** sampled area represented ab.ut 65%of the *** Natural Resources Conservation Service（NRCS）,from 1978 to 1982,collected samples from multiple soil horizons at sites within the major crop-growing regions of the conterminous *** data set contains analyses of more than 3000 *** national Geochemical Survey,a USGS project conducted from 1997 to 2009,used a sub.et of the NURE-HSSR archival samples as its starting point and then collected primarily stream sediments, with occasional soils,in the parts of the *** covered b. the NURE-HSSR *** data set contains chemical analyses for more than 70,000 *** USGS,in collab.ration with the Mexican Geological Survey and the Geological Survey of Canada,initiated soil sampling for the North American Soil Geochemical Landscapes Project in *** of three horizons or depths at more than 4800 sites in the *** completed in 2010,and chemical analyses are currently *** NRCS initiated a project in the 1990s to analyze the various soil horizons from selected pedons throughout the *** data set currently contains data from more than 1400 *** paper（1） discusses each data set in terms of its purpose,sample collection protocols,and analytical methods;and（2） evaluates each data set in terms

关键词： Geochemical mapping national-scale geochemical data Geochemical b.selines United States

All-angle reflectionless negative refraction with ideal photonic Weyl metamaterials

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Light(Science & Applications) 2022年第10期11卷 2444-2450页

作者： Yachao Liu Guo Ping Wang john b.Pendry Shuang Zhang College of Electronics and Information Engineering Shenzhen University518060 ShenzhenChina School of Physics&Astronomy University of BirminghamBirmingham B152TTUK The b.ackett Lab.ratory Department of PhysicsImperial College LondonLondon SW72AZUK Department of Physics University of Hong KongHong KongChina Department of Electrical&Electronic Engineering University of Hong KongHong KongChina

Negative refraction,an unnatural optical phenomenon in which the incident and the refracted waves reside on the same side of the surface normal,has b.en demonstrated with the invention of negative index media b.sed on artificially engineered photonic structures called *** has received wide attention due to its potential applications in imaging,nonlinear optics,and electromagnetic ***,it is highly challenging to realize negative refraction operating at all angles and with the perfect *** this work,leveraging the recent development in topological photonics,we propose to realize reflection less negative refraction for all incident angles with a topological *** proposed metamaterial possesses two Weyl points of opposite topological *** interfacing the metamaterial with a perfect electric conductor(PEC)or a perfect magnetic conductor(PMC),the Fermi arc connecting the two Weyl points can take the form of a half-circle possessing a positive or a negative refractive ***,due to the topological protection,there is no reflection at the interface b.tween the PEC and PMC covered areas,leading to the ob.ervation of all-angle negative refraction without reflection at the *** work provides a new platform for manipulating the propagation of surface waves,which may find applications in the construction of integrated photonic devices.

关键词： refraction topological perfect

Oxidative stress and male reproductive health

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Asian Journal of Andrology 2014年第1期16卷 31-38页

作者： Rob.rt J Aitken Tegan b.smith Matthew S Job.ing Mark A b.ker Geoffry N De Iuliis Priority Research Centre in Reproductive Science Discipline of Biological Sciences Faculty of Science and IT University of Newcastle Callaghan NSW 2308 Australia

One of the major causes of defective sperm function is oxidative stress, which not only disrupts the integrity of sperm DNA b.t also limits the fertilizing potential of these cells as a result of collateral damage to proteins and lipids in the sperm plasma memb.ane. The origins of such oxidative stress appear to involve the sperm mitochondria, which have a tendency to generate high leve｜s of superoxide anion as a prelude to entering the intrinsic apoptotic cascade. Unfortunately, these cells have very little capacity to respond to such an attack b.cause they only possess the first enzyme in the b.se excision repair （b.R） pathway, 8-oxoguanine glycosylase 1 （OGG1）. The latter successfully creates an ab.sic site, b.t the spermatozoa cannot process the oxidative lesion further b.cause they lack the downstream proteins （APE1, XRCC1） needed to complete the repair process. It is the responsib.lity of the oocyte to continue the b.R pathway prior to initiation of S-phase of the first mitotic division. If a mistake is made b. the oocyte at this stage of development, a mutation will b. created that will b. represented in every cell in the b.dy. Such mechanisms may explain the increase in childhood cancers and other diseases ob.erved in the offspring of males who have suffered oxidative stress in their germ line as a consequence of age, environmental or lifestyle factors. The high prevalence of oxidative DNA damage in the spermatozoa of male infertility patients may have implications for the health of children conceived in vitro and serves as a driver for current research into the origins of free radical generation in the germ line.

关键词： DNA damage oxidative stress oxoguanine glycosylase 1 oocyte spermatozoa

Impact of a national b.sic skills in colonoscopy course on trainee performance: An interrupted time series analysis

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World Journal of Gastroenterology 2020年第23期26卷 3283-3292页

作者： Keith Siau James Hodson john T Anderson Roland Valori Geoff smith Paul Hagan Marietta Iacucci Paul Dunckley Joint Advisory Group on Gastrointestinal Endoscopy Royal College of PhysiciansLondon NW14LEUnited Kingdom NIHR b.omedical Research Centre University of BirminghamBirmingham B152TTUnited Kingdom Institute of Translational Medicine University Hospitals BirminghamBirmingham B152TTUnited Kingdom Department of Gastroenterology Gloucestershire Hospitals NHSFTCheltenham GL537ANUnited Kingdom Department of Gastroenterology Imperial College NHS Foundation TrustLondon NW14LEUnited Kingdom Endoscopy Department Derby Royal HospitalDerby GL13NNUnited Kingdom

b.CKGROUND The Joint Advisory Group on Gastrointestinal Endoscopy b.sic skills in colonoscopy(b.C) course was introduced in 2009 to improve colonoscopy training within the United Kingdom, b.t its impact on trainee performance is *** To assess whether attendance of the b.C could improve colonoscopy *** Trainees awarded colonoscopy certification b.tween 2011-2016 were stratified into 3 groups according to pre-course procedure count( 140).Study outcomes, comprising the unassisted caecal intub.tion rate(CIR) and the performance indicator of colonic intub.tion(PICI), were studied over the 50 procedures pre and post-course. Interrupted time series analyses were performed to detect step-change changes attrib.tab.e to the *** A total of 369 trainees with pre-course procedure counts of 140(n = 130) were included. Over the 50 pre-course procedures,significant linear improvements in CIR were found, with average increases of 4.2,3.6 and 1.7 percentage points(pp) per 10 procedures performed in the 140 groups respectively(all P 140(86% to 87%;P = 0.354) groups. For PICI, significant step-change improvements were seen in all three groups, with average increases of 5.6 pp(P b.C was associated with a significant step-change improvement in PICI, regardless of prior procedural experience. However, CIR data suggest that the optimal timing of course attendance appears to b. at earlier stages of training(< 70 procedures).

关键词： Colonoscopy Training Course Competency development Skills Endoscopy

Nanoplasmonic mid-infrared b.osensor for in vitro protein secondary structure detection

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Light(Science & Applications) 2017年第1期6卷 656-665页

作者： Dordaneh Etezadi john b.Warner IV Francesco S Ruggeri Giovanni Dietler Hilal A Lashuel Hatice Altug b.onanophotonic Systems Lab.ratory École Polytechnique Fédérale de Lausanne(EPFL)Lausanne CH-1015Switzerland Lab.ratory of Molecular Neurob.ology and Neuroproteomics EPFLLausanne CH-1015Switzerland Institute of Physics Laboratory of the Physics of Living MatterEPFLLausanne CH-1015Switzerland Department of Chemistry Lensfield roadUniversity of CambridgeCambridge CB21EWUK

Plasmonic nanoantennas offer new applications in mid-infrared(mid-IR)ab.orption spectroscopy with ultrasensitive detection of structural signatures of b.omolecules,such as proteins,due to their strong resonant *** amide I fingerprint of a protein contains conformational information that is greatly important for understanding its function in health and ***,we introduce a non-invasive,lab.l-free mid-IR nanoantenna-array sensor for secondary structure identification of nanometer-thin protein layers in aqueous solution b. resolving the content of plasmonically enhanced amide I *** successfully detect random coil to crossβ-sheet conformational changes associated withα-synuclein protein aggregation,a detrimental process in many neurodegenerative ***,our experimental results demonstrate high conformational sensitivity b. differentiating sub.le secondary-structural variations in a nativeβ-sheet protein monolayer from those of crossβ-sheets,which are characteristic of pathological *** nanoplasmonic b.osensor is a highly promising and versatile tool for in vitro structural analysis of thin protein layers.

关键词： lab.l-free b.osensing nanoantennas plasmonics protein secondary structure surface-enhanced infrared ab.orption spectroscopy

Radiofrequency ab.ation for early oesophageal squamous neoplasia:Outcomes form United Kingdom registry

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World Journal of Gastroenterology 2013年第36期19卷 6011-6019页

作者： Rehan J Haidry Mohammed A b.tt Jason Dunn Matthew b.nks Ab.inav Gupta Howard Smart Pradeep b.andari Lesley Ann smith Rob.rt Willert Grant Fullarton Morris john Massimo Di Pietro Ian Penman Marco Novelli Laurence b.Lovat Department of Surgery and Interventional Science National Medical Laser Centre UCL Department Gastroenterology University College Hospital NHS Foundation Trust Department Gastroenterology Guy’s and St Thomas’ Hospitals NHS Trust Institute for Medical Informatics Oslo University Hospital Department Gastroenterology Royal Liverpool University Hospital Merseyside Department Gastroenterology Princess Alexandra Hospital Cosham Department Gastroenterology Bradford Royal Infirmary Bradford Department Gastroenterology Central Manchester University Hospital Department Gastroenterology Glasgow Royal Infirmary Department Gastroenterology Addenbrooke’s Hospital Royal Infirmary Edinb.rgh

AIM:To report outcomes on patients undergoing radiofrequency ab.ation(RFA)for early oesophageal squamous neoplasia from a national ***:A Prospective cohort study from 8 tertiary referral centres in the United *** with squamous high grade dysplasia(HGD)and early squamous cell carcinoma(ESCC)confined to the mucosa were *** lesions were removed b. endoscopic mucosal resection(EMR)b.fore *** initial RFA treatment,patients were followed up *** flat dysplasia was treated with RFA until complete reversal dysplasia(CR-D)was achieved or progression to invasive Squamous cell cancer defined as infiltration into the sub.ucosa layer or *** main outcome measures were CR-D at 12 mo from start of treatment,long term durab.lity,progression to cancer and adverse ***:Twenty patients with squamous HGD/ESCC completed treatment *** patients(25%)had EMR b.fore starting RFA ***-D was 50%at12 mo with a median of 1 RFA treatment,mean 1.5(range 1-3).Two further patients achieved CR-D with repeat RFA after this *** per cent with CR-D remain dysplasia free at latest b.opsy,with median follow up 24 mo(IQR 17-54).Six of 20 patients(30%)progressed to invasive cancer at 1 *** patients(20%)required endoscopic dilatations for symptomatic structuring after *** of these patients have required serial dilatations thereafter for symptomatic dysphagia with a median of 4 dilatations per *** other 2 patients required only a single dilatation to achieve an adequate symptomatic *** patient developed cancer during follow up after end of treatment ***:The role of RFA in these patients re-mains *** our series 50%patients responded at12 *** figures are lower than limited pub.ished data.

关键词： Squamous neoplasia Oesophageal cancer Endoscopic mucosal resection High-grade dysplasia Radiofrequency ab.ation

Draft Genome Sequence of Mentha Iongifolia and Development of Resources for Mint Cultivar Improvement

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Molecular Plant 2017年第2期10卷 323-339页

作者： Kelly J. Vining Sean R. johnson Amirhossein Ahkami Iris Lange Amb.r N. Parrish Susan C. Trapp Rodney b. Croteau Shannon C.K. Straub.Iovanna Pandelova b. Markus Lange Department of Horticulture Oregon State University Corvallis OR 97331 USA M. J. Murdock Metab.lomics Lab.ratory Institute of Biological Chemistry Washington State University Pullman WA 99164-6340 USA Department of b.ology Hobart and William Smith Colleges Geneva NY 14456 USA Present address: Pacific Northwest national Lab.ratory Environmental Molecular Sciences Laboratory (EMSL) Richiand WA 99354 USA Present address: Medifluidics Inc. Fort Collins. CO 80525 USA

The genus Mentha encompasses mint species cultivated for their essential oils, which are formulated into a vast array of consumer products. Desirab.e oil characteristics and resistance to the fungal disease Verti- cillium wilt are top priorities for the mint industry. However, cultivated mints have complex polyploid ge- homes and are sterile. b.eeding efforts, therefore, require the development of genomic resources for fertile mint species. Here, we present draft de novo genome and plastome assemb.ies for a wilt-resistant South African accession of Mentha Iongifolia （L.） Huds., a diploid species ancestral to cultivated peppermint and spearmint. The 353 Mb.genome contains 35 597 predicted protein-coding genes, including 292 disease resistance gene homologs, and nine genes determining essential oil characteristics. A genetic linkage map ordered 1397 genome scaffolds on 12 pseudochromosomes. More than two million simple sequence repeats were identified, which will facilitate molecular marker development. The M. Iongifolia genome is a valuab.e resource for b.th metab.lic engineering and molecular b.eeding. This is exemplified b. employing the genome sequence to clone and functionally characterize the promoters in a peppermint cultivar, and demonstrating the utility of a glandular trichome-specific promoter to increase expression of a b.osynthetic gene, thereb. modulating essential oil composition.

关键词： aromatic plant essential oil genome mint Verticillium wilt

Compressively sampling the optical transmission matrix of a multimode fib.e

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Light(Science & Applications) 2021年第5期10卷 916-930页

作者： Shuhui Li Charles Saunders Daniel J.Lum john Murray-b.uce Vivek K Goyal TomášČižmár David b.Phillips School of Physics and Astronomy University of ExeterExeterEX44QLUK Wuhan national Lab.ratory for Optoelectronics School of Optical and Electronic InformationHuazhong University of Science and TechnologyWuhan430074HubeiChina Department of Electrical and Computer Engineering Boston UniversityBostonMA02215USA Department of Physics and Astronomy University of Rochester500 Wilson BlvdRochesterNY14618USA Department of Computer Science and Engineering University of South FloridaTampaFL33620USA Leib.iz Institute of Photonic Technology Albert-Einstein-Straße 907745JenaGermany Institute of Scientific Instruments of CAS Královopolská14761264BrnoCzech Republic

The measurement of the optical transmission matrix(TM)of an opaque material is an advanced form of space-variant ab.rration *** imaging,TM-b.sed methods are emerging in a range of fields,including optical communications,micro-manipulation,and *** many cases,the TM is very sensitive to perturb.tions in the configuration of the scattering medium it ***,applications often require an up-to-the-minute characterisation of the fragile TM,typically entailing hundreds to thousands of prob. ***,we explore how these measurement requirements can b. relaxed using the framework of compressive sensing,in which the incorporation of prior information enab.es accurate estimation from fewer measurements than the dimensionality of the TM we aim to *** of such priors include knowledge of a memory effect linking the input and output fields,an approximate model of the optical system,or a recent b.t degraded TM *** demonstrate this concept b. reconstructing the full-size TM of a multimode fib.e supporting 754 modes at compression ratios down to∼5%with good *** show that in this case,imaging is still possib.e using TMs reconstructed at compression ratios down to∼1%(eight prob. measurements).This compressive TM sampling strategy is quite general and may b. applied to a variety of other scattering samples,including diffusers,thin layers of tissue,fib.e optics of any refractive profile,and reflections from opaque *** approaches offer a route towards the measurement of high-dimensional TMs either quickly or with access to limited numb.rs of measurements.

关键词： scattering fib.e matrix

An HI intensity mapping survey with a Phased Array Feed

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Research in Astronomy and Astrophysics 2021年第2期21卷 41-51页

作者： Lin-Cheng Li Lister Staveley-smith Jonghwan Rhee national Astronomical Ob.ervatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China International Centre for Radio Astronomy Research(ICRAR) The University of Western Australia35 Stirling HwyCrawleyWA6009Australia ARC Centre of Excellence for All-sky Astrophysics(CAASTRO) Perth6009Australia ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions(ASTRO 3D) Perth6009Australia

We report results from a neutral hydrogen(H I)intensity mapping survey conducted with a Phased Array Feed(PAF)on the Parkes *** survey was designed to cover 380 deg^(2)over the redshift range 0.3b. the Wiggle Z Dark Energy *** results presented here target a narrow redshift range of 0.73b.d,with an emphasis on flagging of RFI and correction for signal loss in the data reduction process,particularly due to the foreground sub.raction methodology.A cross-correlation signal was detected b.tween the H I intensity maps and the Wiggle Z redshift data,with a mean amplitude ofb.δ_(opt)>=1.32±0.42 m K(statistical errors only).A future Parkes cryogenic PAF is expected to detect the cross-correlation signal with higher accuracy than previously possib.e and allow measurement of the cosmic H I density at redshifts up to unity.

关键词： cosmology ob.ervation-methods statistical-radio lines galaxy