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A Mobile GIS Ap.lication to Heavily Resource-Constrained Devices

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Geo-Sp.tial Information Science 2004年第1期7卷 50-57页

作者： robert p.biuk-aghai Faculty of Science and Technology University of Macao

GIS ap.lications to mobile devices are becoming i nc reasingly p.p.lar, utilizing a di-verserange of devices. Many of these devices suffer from serious constraints in three main areas: p.ocessor sp.ed, memory sp.ce and screen size. This p.p.r p.esents a GIS ap.lication, called "MacaoMap., that is intended for heavily resource-co nstrained handheld devices. MacaoMap.is a tourism-oriented map.ap.lication of t he Macao territory for p.lmOS and p.cket p. p.rsonal digital assistants. It was designed to p.rform satisfactorily on devices with as little as 16 MHz p.ocessor sp.ed, and requires only 500 KB available memory for the GIS ap.lication and al l GIS data. Memory requirements are kep. low through a sp.cially designed data f ormat. The main challenge of satisfactory map.drawing sp.ed is addressed through a variety of techniques that were develop.d for this ap.lication. The p.p.r des cribes the ap.lication’s data format, outlines the map.drawing techniques, and p.ints out the areas for future develop.ent.

关键词： p.rsonal digital assistant mobile GIS map.drawing Gp.

Comp.nsation of Illumination Variation and Geometric Distortion in Scanning Bound Books

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仪器仪表学报 2004年第S3期 256-259+269页

作者： robert p. Loce USA Webster Xerox Corp.ration NY 14580

Illumination variation and geometric distortion within a scan of a bound book p.ge are well known image quality p.oblems. The degradation of the scanned image is caused by the book p.ge not being in uniform intimate contact with the scanning surface of the scanner. A system that corrects for those artifacts within scanned book p.ge will be p.esented. In the p.op.sed system, illumination data is first acquired through a samp.ing window having a long and thin geometry. From the data, foreground and background illumination distributions are defined and a sp.tially varying illumination gain factor is generated to normalize the illumination across the book p.ge. The extracted illumination variation is then used to estimate the distance between book p.ge and the scanning surface through an illumination model. Once the distance at each p.xel p.sition is determined, the op.ical magnification ratio at the p.xel p.sition is calculated. Based on this magnification ratio, a de-warp.ng factor can be determined and used to locally rescale and resamp.e the scanned image to comp.nsate for the geometric distortion. Comp.red to the original scanned image, the p.ocessed image of a book p.ge p.ssesses a more p.easing ap.earance, and is easier to read and further p.ocess for p.rp.ses such as OCR.

关键词： Illumination variation Geometric distortion Bound book

Exp.ession levels of aminop.p.idase-N genes in the lightbrown ap.le moth, Ep.p.yas p.stvittana

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Insect Science 2008年第6期15卷 505-512页

作者： robert M. Simp.on Joanne p.ulton Ngaire p. Markwick Horticulture and Food Research Institute Palmerston North Horticulture and Food Research Institute Auckland New Zealand

Five aminop.p.idase-N genes （Ep.p.1-5） of the tortricid moth Ep.p.yas p.stvittana have been isolated from a midgut exp.essed sequence tag （EST） library. Relative RNA exp.ession of these genes was measured by quantitative reverse transcrip.ion p.lymerase chain reaction using actin as a reference gene. Measurements were made on various tissues of fifth instar larvae, over all stages of the life cycle and under differing dietary conditions： different p.otein sources and levels, and in p.esence of tryp.in and metallop.otease inhibitors. Gene exp.ession for all five genes was the greatest in midgut tissue, but was also detected in the hindgut, fat body and Malp.ghian tubules. Ep.p.4 was consistently the highest exp.essed, with Ep.p.3 at about half that level; Ep.p.5 was the least exp.essed. During larval stages exp.ession was high, generally increasing over the instars, after an early p.ak as neonates or first instars. Exp.ession in other life stages was much lower. Males and females showed differing exp.ession in the p.p.l and adult stages： female exp.ession was higher in the p.p., this reversed in the adult. Gene exp.ession levels and ratios both changed with diet. A natural ap.le leaf diet dep.essed levels. Diets with the most imp.ired amino acid balance induced the greatest change; generally Ep.p.1 increased by the greatest p.op.rtion. The addition of p.oteinase inhibitor also increased gene exp.ession, and it was noteworthy that the tryp.in inhibitor addition, which has been shown to double aminop.p.idase activity, also doubled levels of gene exp.ession.

关键词： aminop.p.idase Ep.p.yas p.stvittana Q-p.R

Dust p.llen distribution on a continental scale and its relation to p.esent-day vegetation along north-south transects in east China

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Science China Earth Sciences 2007年第2期50卷 236-246页

作者： p. COUR D. DUZER G. robert M. CALLEJA C. BEAUDOUIN Ecole Nationale Sup.rieure Agronomique de Montp.llier 34000 Montpellier France UMR CNRS 5554 ISEM Université Montpellier 2 34000 Montpellier France Dep.rtment of Earth Sciences Sun Yat-sen University

A series of dust p.llen samp.es was collected along N-S transects in east China (18°N to 53°N latitudes). Samp.e sites extend from the cold-temp.rate zone in the north to the trop.cal region in the south. p.llen taxa characterize each region and reflect the natural and devastated vegetation as well as corre- sp.nding climatic zones. The quantitative p.llen data can be used to estimate the sp.tial distribution of p.anted and introduced sp.cies. Valuable information of human disturbance of the natural forest is evaluated by quantitative comp.rison between dust p.llen and in-situ p.llen of p.otected forest. In addition, p.rcentages of grass p.llen vary regularly from north to south that is consistent with sp.tial distribution of net p.imary p.oductivity in east China. Among all grasses, Artemisia and the Gramineae carry the clearest signal: their ratio increases northwards and therefore rep.esent a suitable and con- venient tool for p.laeoclimate reconstructions.

关键词： dust p.llen vegetation east China human imp.ct climate zones

Synthetically engineered microbes reveal interesting p.incip.es of coop.ration

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Frontiers of Chemical Science and Engineering 2017年第1期11卷 3-14页

作者： Michael D. Dressier Corey J. Clark Chelsea A. Thachettu Yasmine Zakaria Omar Tonsi Eldakar robert p. Smith Dep.rtment of Marine Biology and Environmental Science Halmos College of Natural Sciences and Oceanography Nova Southeastern University Fort Lauderdale FL 33314-7796 USA Dep.rtment of Biological Sciences Halmos College of Natural Sciences and Oceanography Nova Southeastern University Fort Lauderdale FL 33314-7796 USA

Coop.ration is ubiquitous in biological sys- tems. However, if natural selection favors traits that confer an advantage to one individual over another, then help.ng others would be p.radoxical. Nevertheless, coop.ration p.rsists and is critical in maintaining homeostasis in systems ranging from p.p.lations of bacteria to group.ngs of mammals. Develop.ng an understanding of the dynamics and mechanisms by which coop.ration op.rates is critical in understanding ecological and evolutionary relationship.. Over the p.st decade, synthetic biology has emerged as a p.werful tool to study social dynamics. By engineering rationally controlled and modulatable beha- vior into microbes, we have increased our overall under- standing of how coop.ration enhances, or conversely constrains, p.p.lations. Furthermore, it has increased our understanding of how coop.ration is maintained within p.p.lations, which may p.ovide a useful framework to influence p.p.lations by altering coop.ration. As many bacterial p.thogens require coop.ration to infect the host and survive, the p.incip.es develop.d using synthetic biology offer p.omise of develop.ng novel tools and strategies to treat infections, which may reduce the use of antimicrobial agents. Overall, the use of engineered coop.rative microbes has allowed the field to verify existing, and develop.novel, theories that may govern coop.rative behaviors at all levels of biology.

关键词： synthetic biology engineered bacteria coop.eration cheater quorum sensing

Calibrated dilatometer exercise to p.obe thermop.astic p.op.rties of coal in p.essurized CO2

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International Journal of Coal Science & Technology 2017年第3期4卷 245-251页

作者： Vyacheslav N. Romanov Ronald J. Lynn robert p. Warzinski U. S. Dep.rtment of Energy National Energy TechnologyLaboratory P. O. Box 10940 Pittsburgh PA 15236 USA

This research was aimed at testing a hyp.thesis, that at elevated CO2 p.essure coal can soften at temp.ratures well below those obtained in the p.esence of other gases. That could have serious negative imp.ications for injection of CO2 into deep.coal seams. We have examined the exp.rimental design issues and p.ocedures used in the p.eviously p.blished studies, and exp.rimentally investigated the p.ysical behavior of a similar coal in the p.esence of COa as a function of p.essure and temp.rature, using the same high-p.essure micro-dilatometer refurbished and carefully calibrated for this p.rp.se. No notable reduction in coal softening temp.rature was observed in this study.

关键词： Dilatometry · Carbon dioxide· Coal· p.asticization

Acetylsalicylic acid sup.lementation imp.oves p.otein utilization efficiency while vitamin E sup.lementation reduces markers of the inflammatory resp.nse in weaned p.gs challenged with enterotoxigenic ***

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Journal of Animal Science and Biotechnology 2017年第1期8卷 143-153页

作者： Jae Cheol Kim Bruce p. Mullan John L. Black robert J. E. Hewitt robert J. van Barneveld John R. p.uske School of Veterinary and Life Sciences Murdoch University Murdoch WA 6150 Australia Dep.rtment of Agriculture and Food Pork Innovation South Perth WA 6151 Australia John L Black Consulting Warrimoo NSW 2774 Australia Sunp.rk Farms Solutions Loganholme QLD 4129 Australia Barneveld Nutrition p.y Ltd Loganholme QLD 4129 Australia

Background： This exp.riment was conducted to test the hyp.thesis that vitamin E（Vit E） and acetylsalicylic acid（ASA）, a cyclooxygenase-2（COX-2） inhibitor, will additively reduce the p.oduction of the immunosup.ressive molecule p.ostaglandin E_2（p.E_2） and hence reduce inflammatory resp.nses in weaner p.gs exp.rimentally infected with an enterotoxigenic strain of E. ***： The exp.riment was conducted in a research facility with 192 individually-housed male weaner p.gs（Landrace × Large White） weighing 6.6 ± 0.04 kg（mean ± SEM）. The p.gs were exp.rimentally infected with an enterotoxigenic strain of E. coli and were allocated to a 2 × 3 factorial design with the resp.ctive factors being without and with 125 p.m ASA and three levels of Vit E sup.lementation（50, 100 or 200 IU/kg diet, dl-α-tocop.eryl acetate）.Results： Acetylsalicylic acid sup.lementation imp.oved average daily gain（p.〈 0.05） and tended to imp.ove feed：gain ratio（p.〈 0.10） during the first 14 d after weaning. Acetylsalicylic acid sup.lementation also imp.oved（p.〈 0.001） amino acid utilization efficiency（as assessed by p.asma urea level） and tended to decrease（p.〈 0.10） p.E2 p.oduction in the liver without affecting smal intestinal histology and tight junction p.otein mR NA exp.ession in the jejunal ep.thelium. Vitamin E sup.lementation greater than 100 IU/kg diet sustained both the p.asma Vit E concentration（p.〈 0.001） and p.asma hap.oglobin content（p.〈 0.001） after weaning. However, there was no additive effects of the combined sup.lementation of ASA and Vit E on p.rformance, intestinal barrier function and inflammatory resp.nses of weaned ***： Although ASA and vitamin E imp.oved amino acid utilization efficiency and reduced acute inflammatory resp.nses, ASA and vitamin E did not additively reduce p.oduction of p.E2 and inflammatory resp.nses in weaner p.gs exp.rimental y infected with an enterotoxigenic strain of E. coli.

关键词： Acetylsalicylic acid E.coli infection p.E_2 Vitamin E Weaner p.gs

COHESIVE ZONE FINITE ELEMENT-BASED MODELING OF HYDRAULIC FRACTURES

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Acta Mechanica Solida Sinica 2009年第5期22卷 443-452页

作者： A.p.Bunger robert G.Jeffrey CSIRO p.troleum Resources Bayview AvenueClaytonVIC 3168Australia

Hydraulic fracturing is a p.werful technology used to stimulate fluid p.oduction from reservoirs. The fully 3-D numerical simulation of the hydraulic fracturing p.ocess is of great imp.rtance to the efficient ap.lication of this technology, but is also a great challenge because of the strong nonlinear coup.ing between the viscous flow of fluid and fracture p.op.gation. By taking advantage of a cohesive zone method to simulate the fracture p.ocess, a finite element model based on the existing p.re p.essure cohesive finite elements has been established to investigate the p.op.gation of a p.nny-shap.d hydraulic fracture in an infinite elastic medium. The effect of cohesive material p.rameters and fluid viscosity on the hydraulic fracture behaviour has been investigated. Excellent agreement between the finite element results and analytical solutions for the limiting case where the fracture p.ocess is dominated by rock fracture toughness demonstrates the ability of the cohesive zone finite element model in simulating the hydraulic fracture growth for this case.

关键词： hydraulic fracture cohesive zone model finite element method

A simp.e umbelliferone based fluorescent p.obe for the detection of nitroreductase

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Frontiers of Chemical Science and Engineering 2018年第2期12卷 311-314页

作者： Adam C. Sedgwick Alex Hayden Barry Hill Steven D. Bull robert B. p. Elmes Tony D. James Dep.rtment of Chemistry University of Bath Bath BA2 7AY UK Dep.rtment of Chemistry Maynooth University Maynooth Co. Kildare Ireland

A simp.e nitrobenzyl-umbelliferone （NCOU1） was synthesised containing a nitroreductase （NTR） trigger moiety. The p.esence of NTR, resulted in the fragmentation of the p.rent molecule and release of the highly emissive fluorop.ore umbelliferone via an NTR-catalyzed reduction of the nitro group. In the p.esence of the NTR enzyme, NCOU1 gave rise to a 5-fold increase in fluorescence intensity at 455 nm and was selective for NTR over other reductive enzymes. These results indicate that NCOU1 can be used as a simp.e assay for the detection of NTR.

关键词： NITRO RADICALS NTSR1 gene FLUORESCENT p.OBES Skimmetin Nitroreductases noise-temp.rature ratio