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Science China Earth Sciences 2006年第12期49卷 1323-1331页

作者： T. P. jones l. Merolla r. j. richard Department of Earth Ocean and Planetary Sciences Cardiff UniversityCardiff CF10 3YE UK School of Biosciences Cardiff University PO Box 911 Cardiff CF10 3US UK

Based on the study of Beijing PM10 bioreactivity with the newly developed plasmid DNA assay method, and analysis for trace elements of PM10, the cause of plasmid DNA damage by PM10 was investigated. The study showed that plasmid DNA oxidative damages by PM10 are of difference in different seasons at various areas. The concentrations of TM50 of PM10 in whole samples respectively collected at urban and comparison sites during winter were 900 μg ml?1 and 74 μg ml?1, while those in their corresponding soluble fractions were 540 μg ml?1 and 86 μg ml?1. In contrast, TM50 contents of PM10 from summer whole samples at urban areas and comparison sites were 116 μg ml?1 and 210 μg ml?1, whereas those in their soluble fractions were 180 μg ml?1 and 306 μg ml?1. The difference of bioreactivity of Beijing PM10 resulted from the variation of trace elements. The oxidative damage of plasmid DNA caused by Pb, Zn, As in PM10 (whole sample) was relatively strong. TM50 and Mn, V, Zn display stronger correlation in the soluble fraction. It implies that Zn could be the major trace element in Beijing PM10 which contributes to oxidative damage to plasmid DNA.

关键词： Beijing PM10 trace metals correlation health effect.

Grass Cover Influences Hydrophysical Parameters and Heterogeneity of Water Flow in a Sandy Soil

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Pedosphere 2011年第6期21卷 719-729页

作者： l.lICHNEr D.j.ElDrIDGE K.SCHACHT N.ZHUKOVA l.HOlKO M.ír j.PECHO Institute of Hydrology Slovak Academy of Sciences Department of Environment Climate Change and Water School of BiologicalEarth and Environmental SciencesUniversity of New South Wales Geography Department Ruhr-University BochumUniversitaetsstrasse M.Nodia Institute of Geophysics Institute of Hydrodynamics Academy of Sciences of the Czech Republic Institute of Atmospheric Physics Academy of Sciences of the Czech Republic

Vegetation cover has a major effect on water flow in soils. Two sites, separated by distance of about 50 m, were selected to quantify the influence of grass cover on hydrophysical parameters and heterogeneity of water flow in a sandy soil emerging during a heavy rain following a long hot, dry period. A control soil （pure sand） with limited impact of vegetation or organic matter was obtained by sampling at 50 cm depth beneath a glade area, and a grassland soil was covered in a 10 cm thick humic layer and colonised by grasses. The persistence of water repellency was measured using the water drop penetration time test, sorptivity and unsaturated hydraulic conductivity using a mini disk infiltrometer, and saturated hydraulic conductivity using a double-ring infiltrometer. Dye tracer experiments were used to assess the heterogeneity of water flow, and both the modified method for estimating effective cross section and an original method for assessing the degree of preferential flow were used to quantify this heterogeneity from the images of dyed soil profiles. Most hydrophysical parameters were substantially different between the two surfaces. The grassland soil had an index of water repellency about 10 times that of pure sand and the persistence of water repellency almost 350 times that of pure sand. Water and ethanol sorptivities in the grassland soil were 7% and 43%, respectively, of those of the pure sand. Hydraulic conductivity and saturated hydraulic conductivities in the grassland soil were 5% and 16% of those of the pure sand, respectively. Dye tracer experiments revealed a stable flow with ＂air-draining＂ condition in pure sand and well-developed preferential flow in grassland soil, corresponding to individual grass tussocks and sinai! micro-depressions. The grassland soil was substantially more water repellent and had 3 times the degree of preferential flow compared to pure sand. The results of this study reinforce our view that the consequences of any change in

关键词： dye tracing grassland soil hydrophobicity infiltration preferential flow

How do small birds evolve in response to climate change?Data from the long-term record at la Brea tar pits

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Integrative Zoology 2020年第4期15卷 249-261页

作者： Katherine l.lONG Donald r.PrOTHErO Valerie j.P.SYVErSON Department of Geological Sciences Cal Poly PomonaPomonaCaliforniaUSA Natural History Museum of los Angeles County Los AngelesCaliforniaUSA Department of Geosciences University of Wisconsin MadisonMadisonWisconsinUSA

Biology textbooks describe the small changes in the beaks of the Galápagos finches as exemplars of how birds evolve in response to environmental ***,recent studies of the abundant fossil birds at rancho la Brea find no evidence of evolutionary responses to the dramatic climate changes of the glacial–interglacial cycle over the past 35000 years:none of the large birds exhibit any change in body size or limb proportions,even during the last glacial maximum approximately 18000–20000 years ago,when the southern California chaparral was replaced by snowy coniferous ***,these are all large birds with large ranges and broad habitat preferences,capable of living in many different *** the smaller birds at la Brea,which have smaller home ranges and narrower habitats,might respond to climate more like Galápagos *** only 3 common small birds at la Brea are the western meadowlark,the yellow-billed magpie and the *** this study,we demonstrate that these birds also show complete stasis over the last glacial–interglacial cycle,with no statistically significant changes between dated *** research suggests that the small-scale changes over short timescales seen in the Galápagos finches are merely fluctuations around a stable morphology,and rarely lead to long-term accumulation of changes or ***,the prevalence of stasis supports the view that long-term directional changes in morphology are quite *** directional changes in morphology occur frequently over short(les,in the long term such changes only rarely remain stable for long enough to appear in the fossil record.

关键词： birds evolution macroevolution microevolution Pleistocene

Crustal reworking and orogenic styles inferred from zircon Hf isotopes:Proterozoic examples from the North Atlantic region

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Geoscience Frontiers 2019年第2期10卷 417-424页

作者： C.j.Spencer C.l.Kirkland A.r.Prave r.A.Strachan V.Pease Earth Dynamics research Group The Institute of Geoscience Research (TIGeR)Department of Applied GeologyCurtin University Centre for Exploration Targeting d Curtin Node Department of Applied GeologyCurtin University Department of Earth and Environmental Sciences University of St Andrews School of Earth and Environmental Sciences University of Portsmouth Department of Geological Sciences Stockholm University

Zircon Hf evolutionary patterns are powerful tools to investiage magma petrogenesis and crustal evolution. The ^(176)Hf/^(177)Hf isotopic signature of a rock is particularly informative and can be used to derive an estimation of the time when mantle extraction and diagnose closed system reworking where successive samples through time define an Hf evolution array dependant on the source lu/Hf ratio. However, many magmatic events require new mantle addition as the thermal impetus for melting pre-existing crust. In this situation, rather than simply reflecting reworking, the isotopic signature indicates mixing with contributions from both reworked crust and new radiogenic input. Different geodynamic settings have different propensities for either reworking or addition of new mantle-derived magma. Hence, Hf-time trends carry within them a record, albeit cryptic, of the evolving geodynamic environment as different tectonic configurations recycle and add new crust at different rates, magnitudes, and from different sources. As an example of the difference in apparent Hf evolution slopes, we present Hf-time compilations from three geographically distinct Meso-to Neoproterozoic orogenic belts in the North Atlantic region whose geodynamic configurations remain a subject of debate. We use the εHf/Ma trajectory to assist in understanding their evolution. The εHf/Ma trajectory of the Sveconorwegian Orogen corresponds to a ^(176)lu/^(177) Hf ratio of 0.012, which implies a process driven primarily by reworking of preexisting crust that is balanced with input from the depleted mantle resulting in a relatively shallowεHf/Ma slope. The Valhalla Orogen reveals a similar comparatively shallow εHf/Ma path. In stark contrast to these patterns is the steep εHf/Ma trajectory of the Grenville Orogen that requires a mixing process involving a greater contribution of old crust of at least ～ 1.8 Ga age. The degree of reworking required to produce the εHf/Ma trend of the Grenville Orogen is co

关键词： Zircon Hf Crustal evolution Grenville Sveconorwegian Valhalla

Characteristics of a gold-doped electrode for application in high-performance lithium-sulfur battery

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journal of Energy Chemistry 2022年第1期31卷 116-128,I0004页

作者： Vittorio Marangon Daniele Di lecce Dan j.l.Brett Paul r.Shearing jusef Hassoun University of Ferrara Department of Chemical and Pharmaceutical SciencesVia Fossato di Mortara 17Ferrara44121Italy Electrochemical Innovation lab Department of Chemical EngineeringUCLLondon WC1E 7JEUnited Kingdom The Faraday Institution Quad OneBecquerel AveHarwell CampusDidcot OX11 ORAUnited Kingdom National Interuniversity Consortium of Materials Science and Technology(INSTM) University of Ferrara Research UnitUniversity of FerraraVia Fossato di Mortara17Ferrara 44121Italy

Bulk sulfur incorporating 3 wt% gold nano-powder is investigated as possible candidate to maximize the fraction of active material in the li-S battery *** material is prepared via simple mixing of gold with molten sulfur at 120℃,quenching at room temperature,and *** comprehensive study reports relevant electrochemical data,advanced X-ray computed tomography(CT)imaging of the positive and negative electrodes,and a thorough structural and morphological characterization of the S:Au 97:3 w/w *** cathode exhibits high rate capability within the range from C/10 to 1C,a maximum capacity above 1300 mAh gs^(-1),and capacity retention between 85%and 91%after 100 cycles at 1C and C/3 *** novel formulation enables a sulfur fraction in the composite cathode film as high as 78 wt%,an active material loading of 5.7 mg cm^(-2),and an electrolyte/sulfur(E/S)ratio of 5μl mg^(-1),which lead to a maximum areal capacity of 5.4 mAh cm^(-2).X-ray CT at the micro-and nanoscale reveals the microstructural features of the positive electrode that favor fast conversion kinetics in the *** analysis of sulfur distribution in the porous cathode displays that electrodeposition during the initial cycle may trigger an activation process in the cell leading to improved ***,the tomography study reveals the characteristics of the lithium anode and the cell separator upon a galvanostatic test prolonged over 300 cycles at a 2C rate.

关键词： lithium-sulfur battery Sulfur loading Electrolyte/sulfur ratio Gold nanoparticles X-ray tomography

Augmented reality system to assist inexperienced pool players

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Computational Visual Media 2016年第2期2卷 183-193页

作者： l.Sousa r.Alves j.M.F.rodrigues lArSy S and Institute of Engineering University of the Algarve lArSy S CIAC and Institute of Engineering University of the Algarve

Pool and billiards are amongst a family of games played on a table with six pockets along the rails. This paper presents an augmented reality tool designed to assist unskilled or amateur players of such games. The system is based on a projector and a Kinect 2 sensor placed above the table, acquiring and processing the game on-the-fly. By using depth information and detecting the table's rails(borders),the balls' positions, the cue direction, and the strike of the ball, computations predict the resulting balls' trajectories after the shot is played. These results—trajectories, visual effects, and menus—are visually output by the projector, making them visible on the snooker table. The system achieves a shot prediction accuracy of 98% when no bouncing occurs.

关键词： computer vision augmented reality(Ar) Kinect pool game

Australian sugarcane soldier fly’s salivary gland transcriptome in response to starvation and feeding on sugarcane crops

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Insect Science 2020年第4期27卷 708-720页

作者： Kayvan Etebari Karel r.lindsay Andrew l.Ward Michael j.Furlong School of Biological Sciences The University of QueenslandBrisbaneQLDAustralia Sugar research Australia Te KowaiQLDAustralia Sugar research Australia IndooroopillyQLDAustralia

The soldier fly is an endemic pest of sugarcane in *** numbers of larvae can cause significant damage to roots and reduce the crop *** is known about the composition and function of the soldier fly salivary gland,its secretions,and their roles in insect—plant *** this study,we performed transcriptome analysis of the salivary glands of starved and sugarcane root-fed soldier fly larvae.A total of 31119 highly expressed assembled contigs were identified in the salivary glands and almost 50%of them showed high levels of similarity to known proteins in Nr *** all the obtained contigs,only 9727 sequences contain an open reading frame of over 100 amino *** 31%of contigs were predicted to encode secretory proteins,including some digestive and detoxifying enzymes and potential *** known salivary secreted peptides such as serine protease,cysteine proteinase inhibitors,antimicrobial peptides and venom proteins were among the top 100 highly expressed *** gene expression analysis revealed significant modulation of 850 transcripts in salivary glands upon exposure to plant roots or starvation ***,we identified some venom proteins which were significantly upregulated in the salivary glands of soldier fly larvae exposed to sugarcane *** other insects and nematodes some of these proteins have been used to manipulate host plant defense systems and facilitate the invasion of the host *** findings provide a further insight into the identification of potential effector proteins involved in soldier fly-sugarcane interactions.

关键词： Inopus salivary gland soldier fly sugarcane pest transcriptome

radiotherapy-customized head immobilization masks:from modeling and analysis to 3D printing

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Nuclear Science and Techniques 2019年第9期30卷 103-118页

作者： M.A.r.loja D.S.Craveiro l.Vieira E.Sousa j.A.rodrigues r.j.F.Portal CIMOSM Centro de Investigacao em Modelacao e Optimizacao de Sistemas Multifuncionais ISEL IPL Instituto Superior de Engenharia de Lisboa Av. Conselheiro Emidio Navarro 1 1959-007 Lisbon Portugal lAETA IDMEC Instituto Superior Teccnico Universidade de Lisboa Av. Rovisco Pais 1 1049-001 Lisbon Portugal Department of Mechanical and Industrial Engineering Faculty of Science and Technology NOVA UNIDEMI Universidade Nova de Lisboa Caparica Portugal H&TrC -Health &Technology research Center ESTeSL - Escola Superior de Tecnologia da Saude de Lisboa Av. D. Joao II Lote 4.69.01 1990-096 Lisbon Portugal Instituto de Biofisica e Engenharia Biomedica Faculdade de Ciencias da Universidade de Lisboa Lisbon Portugal

Immobilization devices may be a valuable aid to ensure the improved effectiveness of radiotherapy treatments where constraining the movements of specific anatomical segments is crucial. This need is also present in other situations, specifically when the superposition of various medical images is required for fine identification and characterization of some pathologies. Because of their structural characteristics, existing head immobilization systems may be claustrophobic and very uncomfortable for patients, during both the modeling and usage stages. Because of this, it is important to minimize all the discomforts related to the mask to alleviate patients’ distress and to simultaneously guarantee and maximize the restraint effectiveness of the mask. In the present work, various head immobilization mask models are proposed based on geometrical information extracted from computerized tomography images and from 3D laser scanning point clouds. These models also consider the corresponding connection to a radiotherapy table, as this connection is easily altered to accommodate various manufacturers’ solutions. A set of materials used in the radiotherapy field is considered to allow the assessment of the stiffness and strength of the masks when submitted to typical loadings.

关键词： Computed tomography 3D laser scanning Geometric modeling Head immobilization devices Stiffness and strength analyses 3D printing

THE POSSIBIlITY OF A NEW rESONANCE OF THrEE-BODY lINEAr CHAIN STrUCTUrE IN THE rEACTION ^(12)C+^(16)O AT E_(c.m)≈33.5MeV

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Chinese Physics letters 1990年第5期7卷 212-215页

作者： KONG Xiangjing P.l.li j.j.Kolata A.Morsad l.Goetting r.A.Kryger S.Dixit r.Tighe W.Chune Shanghai Institute of Nuclear research Academia SinicaShanghai 201800 Department of Physics University of Notre DameNotre DameIndiana 46556U.S.A.

There is a peak in the excitation function of total cross section of low energyα-particles in the reaction ^(12)C+^(16)O at E_(c.m)≈*** experimental distribution of α-particle emitted event has been *** result of theoretical calculation roughly agrees with experimental data,gives an orientation where three-body resonances can be expected,and the information on internal structure of three-body linear chain molecule.

关键词： molecule excitation

Anomaly Detection and Classification in Streaming PMU Data in Smart Grids

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Computer Systems Science & Engineering 2023年第9期46卷 3387-3401页

作者： A.l.Amutha r.Annie Uthra j.Preetha roselyn r.Golda Brunet Department of Computational Intelligence SRM Institute of Science and TechnologyChennai603203India Department of Electrical and Electronics Engineering SRM Institute of Science and TechnologyChennai603203India Department of Computer Science and Engineering Government College of EngineeringSalem636011India

The invention of Phasor Measurement Units(PMUs)produce synchronized phasor measurements with high resolution real time monitoring and control of power system in smart grids that make *** are used in transmitting data to Phasor Data Concentrators(PDC)placed in control centers for monitoring purpose.A primary concern of system operators in control centers is maintaining safe and efficient operation of the power *** can be achieved by continuous monitoring of the PMU data that contains both normal and abnormal *** normal data indicates the normal behavior of the grid whereas the abnormal data indicates fault or abnormal conditions in power *** a result,detecting anomalies/abnormal conditions in the fast flowing PMU data that reflects the status of the power system is critical.A novel methodology for detecting and categorizing abnormalities in streaming PMU data is presented in this *** proposed method consists of three modules namely,offline Gaussian Mixture Model(GMM),online GMM for identifying anomalies and clustering ensemble model for classifying the *** significant features of the proposed method are detecting anomalies while taking into account of multivariate nature of the PMU dataset,adapting to concept drift in the flowing PMU data without retraining the existing model unnecessarily and classifying the *** proposed model is implemented in Python and the testing results prove that the proposed model is well suited for detection and classification of anomalies on the fly.

关键词： Smart Grid PMU data incremental learning classifying anomalies artificial intelligence