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Bacteriological challenges to asbestos cement water distribution pipelines

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Journal of Environmental Sciences 2010年第8期22卷 1203-1208页

作者： dunling Wang d. roy Cullimore Centre for Sustainable Infrastructure Research Institute for Research in Construction National Research Council Canada 6 Research Drive Regina SK S4S 7J7 Canada droycon Bioconcepts Inc. 315 Dewdney Avenue Regina SK S4N 0E7 Canada

Asbestos cement （AC） pipes were commonly installed in the drinking water distribution systems from the mid 1920s to the late 1980s. In recent years, an increase in the number of water main breaks has occurred in the AC portions of some pipe networks, which can be partially attributed to the corrosion of the aged pipes. This study evaluated the potential role that microorganisms may have played in the degeneration and failure of AC pipes. In this study, a fresh AC pipe section was collected from the distribution network of the City of Regina, Canada and examined for microbiological activities and growth on inside surfaces of pipe sample. Black slime bacterial growths were found to be attached to inner pipe surfaces and a distinctively fibrous internal coating （patina） with iron oxides was formed over the time. The microbial populations inside the patina and the black slime were tested with BART^TM testers. Heterotrophic aerobic bacteria （HAB） and slime forming bacteria （SLYM） dominated in both the black growths and inside the patina. Iron related bacteria, denitrification bacteria and sulfate reducing bacteria were also commonly present. Microbial challenge assays were conducted by submerging the cut segments of the AC pipe into selected bacterial cultures for a period of 10 days under both aerobic and anaerobic environments. Weight changes were determined and the surface morphology was examined for each of the assayed pipe segments. Results indicated that acid producing bacteria, SLYM and HAB could facilitate the pipe weight loss under anaerobic environments.

关键词： asbestos cement pipes drinking water distribution network bacteriological challenges biofilms patina

Multi-year MOdIS active fire type classification over the Brazilian Tropical Moist Forest Biome

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International Journal of digital Earth 2017年第1期10卷 54-84页

作者： d.P.roy S.S.Kumar Geospatial Sciences Center of Excellence South Dakota State UniversityBrookingsSDUSA

The Brazilian Tropical Moist Forest Biome(BTMFB)spans almost 4 million km^(2) and is subject to extensive annual fires that have been categorized into deforestation,maintenance,and forest fire *** on fire types is important as they have different atmospheric emissions and ecological impacts.A supervised classification methodology is presented to classify the fire type of MOderate resolution Imaging Spectroradiometer(MOdIS)active fire detections using training data defined by consideration of Brazilian government forest monitoring program annual land cover maps,and using predictor variables concerned with fuel flammability,fuel load,fire behavior,fire seasonality,fire annual frequency,proximity to surface transportation,and local *** fire seasonality,local temperature,and fuel flammability were the most influential on the *** fire type results for all 1.6 million MOdIS Terra and Aqua BTMFB active fire detections over eight years(2003–2010)are presented with an overall fire type classification accuracy of 90.9%(kappa 0.824).The fire type user’s and producer’s classification accuracies were respectively 92.4%and 94.4%(maintenance fires),88.4%and 87.5%(forest fires),and,88.7%and 75.0%(deforestation fires).The spatial and temporal distribution of the classified fire types are presented and are similar to patterns reported in the available recent literature.

关键词： Earth observation land cover remote sensing

Global operational land imager Landsat-8 reflectance-based active fire detection algorithm

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International Journal of digital Earth 2018年第2期11卷 154-178页

作者： S.S.Kumar d.P.roy Plant and Environmental Sciences New Mexico State UniversityLas CrucesNMUSA Geospatial Sciences Center of Excellence South Dakota State UniversityBrookingsSDUSA

A global operational land imager(GOLI)Landsat-8 daytime active fire detection algorithm is *** utilizes established contextual active fire detection approaches but takes advantage of the significant increase in fire reflectance in Landsat-8 band 7(2.20μm)relative to band 4(0.66μm).The detection thresholds are fixed and based on a statistical examination of 39 million non-burning Landsat-8 ***-temporal tests based on band 7 reflectance and relative changes in normalized difference vegetation index in the previous six months are used to reduce commissions *** probabilities of active fire detection for the GOLI and two recent Landsat-8 active fire detection algorithms are simulated to provide insights into their performance with respect to the fire size and *** algorithms are applied to 11 Landsat-8 images that encompass a range of burning conditions and *** and omission errors are assessed by visual interpretation of detected active fire locations and by examination of the Landsat-8 images and higher spatial resolution Google Earth *** GOLI algorithm has lower omission and comparable commission errors than the recent Landsat-8 active fire detection *** GOLI algorithm has demonstrable potential for global application and is suitable for implementation with other Landsat-like reflective wavelength sensors.

关键词： Earth observation remote sensing visible/infrared remote sensing

Vibration of an infinite inhomogeneous transversely isotropic viscoelastic medium with cylindrical hole

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Applied Mathematics and Mechanics(English Edition) 2008年第3期29卷 367-378页

作者： d.P.Acharya Indrajit roy P.K.Biswas 109/3 Kailash Roy Chowdhury RoadBarrackporeKolkata 700120WBIndia Brahmapara SimuraliNadia 741248WBIndia department of Mathematics Kanchrapara CollegeKanchraparaWBIndia

This paper investigates the influences of higher order viscoelasticity and the inhomogeneities of the transversely isotropic elastic parameters on the disturbances in an infinite medium, caused by the presence of a transient radial force or twist on the surface of a cylindrical hole with circular cross section. Following Voigt＇s model for higher order viscoelasticity, the nonvanishing stress components valid for a transversely isotropic and higher order viscoelastic solid medium have been deduced in terms of radial displacement component. Considering the power law variation of elastic and viscoelastic parameters, the stress equation of motion has been developed. Solving this equation under suitable boundary conditions, due to transient forces and twists, radial displacement and relevant stress components have been determined in terms of modified Bessel functions. The problem for the presence of transient radial force has been numerically analysed. Modulations of displacement and stresses due to different order of viscoelasticity and inhomogeneity have been graphically depicted. The numerical study of the disturbance caused by the presence of twist on the surface may be similarly done but is not pursued in this paper.

关键词： higher order viscoelasticity inhomogeneity and transversely isotropy transient force and twist radial displacement stress components modified Bessel functions

Putting meaning into NETMAR-the open service network for marine environmental data

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International Journal of digital Earth 2014年第10期7卷 811-828页

作者： Adam M.Leadbetter roy K.Lowry d.Oliver Clements British Oceanographic data Centre LiverpoolUK Plymouth Marine Laboratory PlymouthUK

The open service network for marine environmental data(NETMAR)project uses semantic web technologies in its pilot system which aims to allow users to search,download and integrate satellite,in situ and model data from open ocean and coastal *** semantic web is an extension of the fundamental ideas of the World Wide Web,building aweb of datathrough annotation of metadata and data with hyperlinked *** the framework of the NETMAR project,an interconnected semantic web resourcewasdeveloped to aid in dataandweb service discovery and to validate Open Geospatial Consortium Web Processing Service orchestration.A second semantic resource was developed to support interoper-ability of coastal web atlases across jurisdictional *** paper outlines the approach taken to producing the resource registry used within the NETMAR project and demonstrates the use of these semantic resources to support user interactions with *** interconnected semantic resources allow the increased ability to share and disseminate data through the facilitation of interoperability between data *** formal representation of geospatial knowledge to advance geospatial interoperability is a growing research *** and methods such as those outlined in this paper have the potential to support these efforts.

关键词： geoinformatics oceanography geospatial data integration

Changes in electrical conductivity of liquid foods during ohmic heating

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International Journal of Agricultural and Biological Engineering 2014年第5期7卷 133-138页

作者： Shivmurti Srivastav Srishti roy department of Food Processing Technology A.D.Patel Institute of TechnologyNew Vallabh Vidya NagarAnandGujarat 388121India

Ohmic heating is a food processing method in which alternating current(AC)went through a food sample and resulted in internal energy generation in *** is an alternative fast heating *** principal advantage is the ability to rapidly and uniformly heat food materials of various *** ohmic heating,change in electrical conductivity was *** intensity of food materials’electrical conductivity or overall resistance critically controls ohmic heating *** ohmic heating set-up was prepared under this *** juice was heated(about 32℃ to 80℃)in a batch type ohmic heater at different voltage gradients in the range of 50-70 V/*** was statistically found that the voltage gradient had significant impact on conductivity and system performance coefficient(SPC)(Pded that the electrical conductivity values linearly increased with *** SPCs of the system ranged between 0.779 and *** value of R2 of the linear model was greater than 0.98.

关键词： ohmic heating electrical conductivity thermal conductivity liquid foods

Hydrodynamics of gas-solid fluidization of a homogeneous ternary mixture in a conical bed:Prediction of bed expansion and bed fluctuation ratios

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Particuology 2013年第6期11卷 681-688页

作者： d.T.K.dora S.R.Panda Y.K.Mohanty G.K.roy department of Chemical Engineering Gandhi Institute of Engineering and Technology(GIET) department of Chemical Engineering National Institute of Technology(NIT)

Hydrodynamic characteristics of fluidization in a conical or tapered bed differ from those in a columnar bed because the superficial velocity in the bed varies in the axial direction. Fixed and fluidized regions could coexist and sharp variations in pressure drop could occur, thereby giving rise to a noticeable pressure drop-flow rate hysteresis loop under incipient fluidization conditions. To explore these unique properties, several experiments were carried out using homogeneous, well-mixed, ternary mixtures with three dif- ferent particle sizes at varying composition in gas-solid conical fluidized beds with varying cone angles. The hydrodynamic characteristics determined include the minimum fluidization velocity, bed fluctuation, and bed expansion ratios. The dependence of these quantities on average particle diameter, mass fraction of the fines in the mixture, initial static bed height, and cone angle is discussed. Based on dimensional analysis and factorial design, correlations are developed using the system parameters, i.e. geometry of the bed （cone angle）, particle diameter, initial static bed height, density of the solid, and superficial velocity of the fluidizing medium. Experimental values of minimum fluidization velocity, bed fluctuation, and bed expansion ratios were found to agree well with the developed correlations.

关键词： Gas-solid fluidization Conical bed Homogeneous ternary mixtures Bed fluctuation ratio Bed expansion ratio

Nutritional stress reduces flight performance and exploratory behavior in a butterfly

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Insect Science 2019年第5期26卷 897-910页

作者： Elisabeth Reim danny Eichhorn Jan d.roy Philip O.M.Steinhoff Klaus Fischer Zoological Institute and Museum Greifswald UniversityGreifswaldGermany

Anthropogenic global change, including agricultural intensification and climate change, poses a substantial challenge to many herbivores due to a reduced availability of feeding resources. The concomitant food stress is expected to detrimentally affect performance, amongst others in dispersal-related traits. Thus, while dispersal is of utmost importance to escape from deteriorating habitat conditions, such conditions may negatively feedback on the ability to do so. Therefore, we here investigate the impact of larval and adult food stress on traits related to dispersal ability, including morphology, physiology, flight performance, and exploratory behavior, in a butterfly. We show that inadequate nutrition during development and in the adult stage dim inishes flight performance, despite som e reallocation of somatic resources. detrimental effects of food stress on flight performance were mainly caused by reductions in body mass and storage reserves. Similar results were found for exploratory behavior. Furthermore, exploratory behavior was found to be (moderately) repeatable at the individual level, which might indicate the existence of a personality trait. This notion is further supported by the fact that flight performance and exploratory behavior were positively correlated, potentially suggesting the existence of a dispersal syndrome. In summary, our findings may have important implications for dispersal in natural environments, as the conditions requiring dispersal the m ost impair flight ability and thereby likely dispersal rates.

关键词： condition dispersal syndrome flight ability food stress habitat degradation resource allocation

Heat stroke induced cerebellar dysfunction:A “forgotten syndrome”

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World Journal of Clinical Cases 2013年第8期1卷 260-261页

作者： Athula d Kosgallana Shreyashee Mallik Vishal Patel roy G Beran department of Neurology Liverpool HospitalLiverpoolNSW 2170Australia School of Medicine Griffith UniversityBrisbaneQLD 4222Australia Strategic Health Evaluation NorthbridgeNSW 1560Australia

We report a case of heat stroke induced acute cerebellar dysfunction, a rare neurological disease characterized by gross cerebellar dysfunction with no acute radiographic changes, in a 61 years old ship captain presenting with slurred speech and gait ataxia. A systematic review of the literature on heat stroke induced cerebellar dysfunction was performed, with a focus on investigations, treatment and outcomes. After review of the literature and detailed patient investigation it was concluded that this patient suffered heat stroke at a temperature less than that quoted in the literature.

关键词： Heat stroke Cerebellar syndrome Ataxic hemiparesis Hyperthermia Cerebellar atrophy