bluuebunny/crossref_metadata_2025 huggingface dataset:
SU-8 Cantilevers for Bio/chemical Sensing; Fabrication, Characterisation and Development of Novel Read-out Methods
Authors: Nordström Maria , Keller Stephan , Lillemose Michael , Johansson Alicia , Dohn Søren , Haefliger Daniel , Blagoi Gabriela , Havsteen-Jakobsen Mogens , Boisen Anja
Published: December 2008

Here, we present the activities within our research group over the last five yearswith cantilevers fabricated in the polymer SU-8. We believe that SU-8 is an interestingpolymer for fabrication of cantilevers for bio/chemical sensing due to its simple processingand low Young’s modulus. We show examples of different integrated read-out methodsand their characterisation. We also show that SU-8 cantilevers have a reduced sensitivity tochanges in the environmental temperature and pH of the buffer solution. Moreover, weshow that the SU-8 cantilever surface can be functionalised directly with receptormolecules for analyte detection, thereby avoiding gold-thiol chemistry.
A Fluorescent Sensor for Dinitrobenzoic Acid Based on a Cyanuric Acid and Xanthene Skeleton
Authors: Muñiz Francisco M. , Simón Luis , Sáez Silvia , Raposo César , Alcázar Victoria , Morán Joaquín R.
Published: December 2008

A new fluorescent sensor based on a dimethylxanthene skeleton has beensynthesized. Because of its oxyanion hole structure, this receptor includes a suitablecavity for the association of carboxylic acids. The receptor’s fluorescence is quenchedupon addition of dinitrobenzoic acid.
Multiscale Unsupervised Segmentation of SAR Imagery Using the Genetic Algorithm
Authors: Wen Xian-Bin , Zhang Hua , Jiang Ze-Tao
Published: December 2008

A valid unsupervised and multiscale segmentation of synthetic aperture radar(SAR) imagery is proposed by a combination GA-EM of the Expectation Maximization(EM) algorith with the genetic algorithm (GA). The mixture multiscale autoregressive(MMAR) model is introduced to characterize and exploit the scale-to-scale statisticalvariations and statistical variations in the same scale in SAR imagery due to radar speckle,and a segmentation method is given by combining the GA algorithm with the EMalgorithm. This algorithm is capable of selecting the number of components of the modelusing the minimum description length (MDL) criterion. Our approach benefits from theproperties of the Genetic and the EM algorithm by combination of both into a singleprocedure. The population-based stochastic search of the genetic algorithm (GA) exploresthe search space more thoroughly than the EM method. Therefore, our algorithm enablesescaping from local optimal solutions since the algorithm becomes less sensitive to itsinitialization. Some experiment results are given based on our proposed approach, andcompared to that of the EM algorithms. The experiments on the SAR images show that theGA-EM outperforms the EM method.
Sensitive Detection of Haloperidol and Hydroxyzine at Multi-Walled Carbon Nanotubes-Modified Glassy Carbon Electrodes
Authors: Huang Fei , Peng Youyuan , Jin Guiying , Zhang Song , Kong Jilie
Published: December 2008

Haloperidol (i.e. HPD) and hydroxyzine (i.e. HXY), two effective and important tranquilizers with low redox activity, were found to generate an irreversible anodic peak at about +0.86 V (vs. SCE) or two anodic peaks at about +0.83 and +0.91 V in 0.05 M NaH2PO4-Na2HPO4 (pH=7.0) buffer solution with a multi-walled carbon nanotubes-modified glassy carbon electrode (i.e. MWNTs/GC), respectively. Their sensitive and quantitative measurement based on the first two anodic peaks was established under the optimum conditions. The anodic peak current was linear to HPD and HXY concentration from 1×10-7 to 2.5 ×10-5 M and 5×10-8 to 2.5 ×10-5 M, the detection limits obtained were 8×10-9 and 5×10-9 M, separately. The modified electrode exhibited some excellent characteristics including easy regeneration, high stability, good reproducibility and selectivity. The method proposed was successfully applied to the detection of HPD and HXY in drug tablets and proved to be reliable compared with ultraviolet spectrophotometry. The modified electrode was characterized by electrochemical methods.
Electrochemical Determination of Trace Sudan I Contamination in Chili Powder at Carbon Nanotube Modified Electrodes
Authors: Ming Liang , Xi Xia , Chen Tingting , Liu Jie
Published: December 2008

We have developed a simple, convenient and inexpensive voltammetric method for determining trace Sudan I contamination in chili powder, based on the catalyzed electrochemical reduction of Sudan I at the carbon nanotube modified electrode. Under optimized conditions, the method exhibited acceptable analytical performance in terms of linearity (over the concentration range 6.0×10–7 to 7.5×10–5 M, r = 0.9967), detection limit (2.0×10–7 M) and reproducibility (RSD = 4.6%, n=10, for 2.0×10–5 M Sudan I).
Sensor Performance Requirements for the Retrieval of Atmospheric Aerosols by Airborne Optical Remote Sensing
Authors: Seidel Felix , Schläpfer Daniel , Nieke Jens , Itten Klaus I.
Published: December 2008

This study explores performance requirements for the retrieval of the atmospheric aerosol optical depth (AOD) by airborne optical remote sensing instruments. Independent of any retrieval techniques, the calculated AOD retrieval requirements are compared with the expected performance parameters of the upcoming hyperspectral sensor APEX at the reference wavelength of 550nm. The AOD accuracy requirements are defined to be capable of resolving transmittance differences of 0.01 to 0.04 according to the demands of atmospheric corrections for remote sensing applications. For the purposes of this analysis, the signal at the sensor level is simulated by radiation transfer equations. The resulting radiances are translated into the AOD retrieval sensitivity (Δτλaer ) and compared to the available measuring sensitivity of the sensor (NE ΔLλsensor). This is done for multiple signal-to-noise ratios (SNR) and surface reflectance values. It is shown that an SNR of 100 is adequate for AOD retrieval at 550nm under typical remote sensing conditions and a surface reflectance of 10% or less. Such dark surfaces require the lowest SNR values and therefore offer the best sensitivity for measuring AOD. Brighter surfaces with up to 30% reflectance require an SNR of around 300. It is shown that AOD retrieval for targets above 50% surface reflectance is more problematic with the current sensor performance as it may require an SNR larger than 1000. In general, feasibility is proven for the analyzed cases under simulated conditions.
A Dynamic Range Expansion Technique for CMOS Image Sensors with Dual Charge Storage in a Pixel and Multiple Sampling
Authors: Shafie Suhaidi , Kawahito Shoji , Itoh Shinya
Published: December 2008

A dynamic range expansion technique for CMOS image sensors with dual charge storage in a pixel and multiple sampling technique is presented. Each pixel contains a photodiode and a storage diode which is connected to the photodiode via a separation gate. The sensitivity of the signal charge in the storage diode can be controlled either by a separation gate which limits the charge to flow into the storage diode or by controlling the accumulation time in the storage diode. The operation of the sensitivity control with separation gate techniques is simulated and it is found that a blocking layer to the storage diode plays an important role for high controllability of sensitivity of the storage diode. A prototype chip for testing multiple short time accumulations is fabricated and measured.
Assessment and Analysis of QuikSCAT Vector Wind Products for the Gulf of Mexico: A Long-Term and Hurricane Analysis
Authors: Sharma Neha , D’Sa Eurico
Published: December 2008

The northern Gulf of Mexico is a region that has been frequently impacted in recent years by natural disasters such as hurricanes. The use of remote sensing data such as winds from NASA’s QuikSCAT satellite sensor would be useful for emergency preparedness during such events. In this study, the performance of QuikSCAT products, including JPL’s latest Level 2B (L2B) 12.5 km swath winds, were evaluated with respect to buoy-measured winds in the Gulf of Mexico for the period January 2005 to February 2007. Regression analyses indicated better accuracy of QuikSCAT’s L2B DIRTH, 12.5 km than the Level 3 (L3), 25 km wind product. QuikSCAT wind data were compared directly with buoy data keeping a maximum time interval of 20 min and spatial interval of 0.1° (≈10 km). R2 values for moderate wind speeds were 0.88 and 0.93 for L2B, and 0.75 and 0.89 for L3 for speed and direction, respectively. QuikSCAT wind comparisons for buoys located offshore were better than those located near the coast. Hurricanes that took place during 2002-06 were studied individually to obtain regressions of QuikSCAT versus buoys for those events. Results show QuikSCAT’s L2B DIRTH wind product compared well with buoys during hurricanes up to the limit of buoy measurements. Comparisons with the National Hurricane Center (NHC) best track analyses indicated QuikSCAT winds to be lower than those obtained by NHC, possibly due to rain contamination, while buoy measurements appeared to be constrained at high wind speeds. This study has confirmed good agreement of the new QuikSCAT L2B product with buoy measurements and further suggests its potential use during extreme weather conditions in the Gulf of Mexico.
A Novel Optical Fiber Sensor for Steel Corrosion in Concrete Structures
Authors: Leung Christopher K.Y. , Wan Kai Tai , Chen Liquan
Published: December 2008

Steel corrosion resulting from the penetration of chloride ions or carbon dioxide is a major cause of degradation for reinforced concrete structures,. The objective of the present investigation was to develop a low-cost sensor for steel corrosion, which is based on a very simple physical principle. The flat end of a cut optical fiber is coated with an iron thin film using the ion sputtering technique. Light is then sent into a fiber embedded in concrete and the reflected signal is monitored. Initially, most of the light is reflected by the iron layer. When corrosion occurs to remove the iron layer, a significant portion of the light power will leave the fiber at its exposed end, and the reflected power is greatly reduced. Monitoring of the reflected signal is hence an effective way to assess if the concrete environment at the location of the fiber tip may induce steel corrosion or not. In this paper, first the principle of the corrosion sensor and its fabrication are described. The sensing principle is then verified by experimental results. Sensor packaging for practical installation will be presented and the performance of the packaged sensors is assessed by additional experiments.
Innovative Sensors for Environmental Monitoring in Museums
Authors: Bacci Mauro , Cucci Costanza , Mencaglia Andrea Azelio , Mignani Anna Grazia
Published: December 2008

Different physical and chemical factors, such as light, temperature, relative humidity, pollutants and so on, can affect works of art on display. Each factor does not act individually, but its effect can be enhanced or accelerated by the presence of other factors. Accordingly, an evaluation of the impact of the whole environment on art objects is recognized as an essential requirement for conservation purposes. To meet the most up-todate guidelines on preventive conservation, in recent years several scientific projects supported by the EC were aimed at developing innovative tools that could complement the standard methods for environmental monitoring in museums. These research projects produced a new generation of passive sensors that are capable of taking into account the overall environmental effects by mimicking in some way the behaviour of real works of art. The main goal of the present paper is to provide a survey of these sensors, which represent a new frontier in the environmental control in museums. Furthermore, the use of optical fibres, as both intrinsic sensors and devices for interrogating sensors, will also be illustrated, and examples of their use in the cultural heritage field will be reported.
Role of Satellite Sensors in Groundwater Exploration
Authors: Mukherjee Saumitra
Published: December 2008

Spatial as well as spectral resolution has a very important role to play in water resource management. It was a challenge to explore the groundwater and rainwater harvesting sites in the Aravalli Quartzite-Granite-Pegmatite Precambrian terrain of Delhi, India. Use of only panchromatic sensor data of IRS-1D satellite with 5.8-meter spatial resolution has the potential to infer lineaments and faults in this hard rock area. It is essential to identify the location of interconnected lineaments below buried pediment plains in the hard rock area for targeting sub-surface water resources. Linear Image Self Scanning sensor data of the same satellite with 23.5-meter resolution when merged with the panchromatic data has produced very good results in delineation of interconnected lineaments over buried pediment plains as vegetation anomaly. These specific locations of vegetation anomaly were detected as dark red patches in various hard rock areas of Delhi. Field investigation was carried out on these patches by resistivity and magnetic survey in parts of Jawaharlal Nehru University (JNU), Indira Gandhi national Open University, Research and Referral Hospital and Humayuns Tomb areas. Drilling was carried out in four locations of JNU that proved to be the most potential site with ground water discharge ranging from 20,000 to 30,000 liters per hour with 2 to 4 meters draw down. Further the impact of urbanization on groundwater recharging in the terrain was studied by generating Normalized difference Vegetation Index (NDVI) map which was possible to generate by using the LISS-III sensor of IRS-1D satellite. Selection of suitable sensors has definitely a cutting edge on natural resource exploration and management including groundwater.
Electrochemical Sensors for Clinic Analysis
Authors: Wang You , Xu Hui , Zhang Jianming , Li Guang
Published: December 2008

Demanded by modern medical diagnosis, advances in microfabrication technology have led to the development of fast, sensitive and selective electrochemical sensors for clinic analysis. This review addresses the principles behind electrochemical sensor design and fabrication, and introduces recent progress in the application of electrochemical sensors to analysis of clinical chemicals such as blood gases, electrolytes, metabolites, DNA and antibodies, including basic and applied research. Miniaturized commercial electrochemical biosensors will form the basis of inexpensive and easy to use devices for acquiring chemical information to bring sophisticated analytical capabilities to the non-specialist and general public alike in the future.
An Optical Tomography System Using a Digital Signal Processor
Authors: Rahim Ruzairi Abdul , Thiam Chiam Kok , Rahiman Mohd. Hafiz Fazalul
Published: December 2008

The use of a personal computer together with a Data Acquisition System (DAQ) as the processing tool in optical tomography systems has been the norm ever since the beginning of process tomography. However, advancements in silicon fabrication technology allow nowadays the fabrication of powerful Digital Signal Processors (DSP) at a reasonable cost. This allows this technology to be used in an optical tomography system since data acquisition and processing can be performed within the DSP. Thus, the dependency on a personal computer and a DAQ to sample and process the external signals can be reduced or even eliminated. The DSP system was customized to control the data acquisition process of 16x16 optical sensor array, arranged in parallel beam projection. The data collected was used to reconstruct the cross sectional image of the pipeline conveyor. For image display purposes, the reconstructed image was sent to a personal computer via serial communication. This allows the use of a laptop to display the tomogram image besides performing any other offline analysis.
Relationship Between Remotely-sensed Vegetation Indices, Canopy Attributes and Plant Physiological Processes: What Vegetation Indices Can and Cannot Tell Us About the Landscape
Authors: Glenn Edward P. , Huete Alfredo R. , Nagler Pamela L. , Nelson Stephen G.
Published: December 2008

Vegetation indices (VIs) are among the oldest tools in remote sensing studies. Although many variations exist, most of them ratio the reflection of light in the red and NIR sections of the spectrum to separate the landscape into water, soil, and vegetation. Theoretical analyses and field studies have shown that VIs are near-linearly related to photosynthetically active radiation absorbed by a plant canopy, and therefore to light-dependent physiological processes, such as photosynthesis, occurring in the upper canopy. Practical studies have used time-series VIs to measure primary production and evapotranspiration, but these are limited in accuracy to that of the data used in ground truthing or calibrating the models used. VIs are also used to estimate a wide variety of other canopy attributes that are used in Soil-Vegetation-Atmosphere Transfer (SVAT), Surface Energy Balance (SEB), and Global Climate Models (GCM). These attributes include fractional vegetation cover, leaf area index, roughness lengths for turbulent transfer, emissivity and albedo. However, VIs often exhibit only moderate, non-linear relationships to these canopy attributes, compromising the accuracy of the models. We use case studies to illustrate the use and misuse of VIs, and argue for using VIs most simply as a measurement of canopy light absorption rather than as a surrogate for detailed features of canopy architecture. Used this way, VIs are compatible with "Big Leaf" SVAT and GCMs that assume that canopy carbon and moisture fluxes have the same relative response to the environment as any single leaf, simplifying the task of modeling complex landscapes.
Assessment of the Spatial Co-registration of Multitemporal Imagery from Large Format Digital Cameras in the Context of Detailed Change Detection
Authors: Coulter Lloyd L. , Stow Douglas A.
Published: December 2008

Large format digital camera (LFDC) systems are becoming more broadly available and regularly collect image data over large areas. Spectral and radiometric attributes of imagery from LFDC systems make this type of image data appropriate for semi-automated change detection. However, achieving accurate spatial co-registration between multitemporal image sets is necessary for semi-automated change detection. This study investigates the accuracy of co-registration between multitemporal image sets acquired using the Leica Geosystems ADS40, Intergraph Z/I Imaging® DMC, and Vexcel UltraCam-D sensors in areas of gentle, moderate, and extreme terrain relief. Custom image sets were collected and orthorectified by imagery vendors, with guidance from the authors. Results indicate that imagery acquired by vendors operating LFDC systems may be coregistered with pixel or sub-pixel level accuracy, even for environments with high terrain relief. Specific image acquisition and processing procedures facilitating this level of coregistration are discussed.
Identification of Metals (Heavy and Radioactive) in Drinking Water by an Indirect Analysis Method Based on Scale Tests
Authors: Rajkovic Miloš B. , Lacnjevac Caslav M. , Ralevic Nebojsa R. , Stojanović Mirjana D. , Tosković Dragan V. , Pantelic Gordana K. , Ristic Nikola M. , Jovanic Sasa
Published: December 2008

The analysis of water quality, regarding the content of metals, especially heavy and radioactive ones, has been carried out in an indirect way, by testing scale formed in a hot-water heater, using water from the water-supply network of the city of Belgrade – the district of New Belgrade. The determination of the composition and the structure of the scale has resulted in its complete identification, and its crystallochemical formula has been defined. It has unequivocally been established that the obtained results are within the tolerance boundary with the results acquired by a conventional analysis of water, when it is a matter of very low concentrations. The presence of radioactive elements of uranium and strontium in a scale sample has been found and the way of their penetrating its composition and structure has been explained. Applying the fractional extraction method, uranium has been established to be of an anthropogenic origin.
Compound Cellular Imaging of Laser Scanning Confocal Microscopy by Using Gold Nanoparticles and Dyes
Authors: Tsai Shiao-Wen , Chen Yi-Yun , Liaw Jiunn-Woei
Published: December 2008

Combining the scattered light of gold nanoparticles (GNPs) and the fluorescence of dye molecules, a compound cellular imaging of laser scanning confocal microscopy (LSCM) is obtained. The human breast cancer cell line (MDA-MB-435S, BCRC 60429) is used for experiment. These cells are incubated with a glucose medium containing GNPs for 26 hours, and then are stained by Prodium Iodide (PI) for their nuclei. By using a single laser to illuminate these cells and adjusting the ranges of two bandpass filters for the detection, the scattered light from the GNPs and the fluorescence of PI can be induced simultaneously, but be detected separately without crosstalk. Furthermore, a compound cellular image can be obtained by merging the two images of the expressions of GNP and PI together. From the TEM images of these cells, it is observed that GNPs are aggregated in the vesicles of the cytoplasm due to the cell’s endocytosis. The aggregation of GNPs makes the surface plasmon resonance band of GNPs broadened, so that strong scattered light from GNPs can be generated by the illumination of different-wavelength lasers (458, 488, 514, 561, and 633 nm).
Personalization of Rule-based Web Services
Authors: Choi Okkyung , Han Sang Yong
Published: December 2008

Nowadays Web users have clearly expressed their wishes to receive personalized services directly. Personalization is the way to tailor services directly to the immediate requirements of the user. However, the current Web Services System does not provide any features supporting this such as consideration of personalization of services and intelligent matchmaking. In this research a flexible, personalized Rule-based Web Services System to address these problems and to enable efficient search, discovery and construction across general Web documents and Semantic Web documents in a Web Services System is proposed. This system utilizes matchmaking among service requesters’, service providers’ and users’ preferences using a Rule-based Search Method, and subsequently ranks search results. A prototype of efficient Web Services search and construction for the suggested system is developed based on the current work.
Conductometric Microbiosensors for Environmental Monitoring
Authors: Jaffrezic-Renault Nicole , Dzyadevych Sergei V.
Published: December 2008

This review presents the principles of conductometric measurements in ionic media and the equivalent electrical circuits of different designs for conductometric measurements. These types of measurements were first applied for monitoring biocatalytic reactions. The use of conductometric microtransducers is then presented and detailed in the case of pollutant detection for environmental monitoring. Conductometric biosensors have advantages over other types of transducers: they can be produced through inexpensive thinfilm standard technology, no reference electrode is needed and differential mode measurements allow cancellation of a lot of interferences. The specifications obtained for the detection of different pesticides, herbicides and heavy metal ions, based on enzyme inhibition, are presented as well as those obtained for the detection of formaldehyde, 4- chlorophenol, nitrate and proteins as markers of dissolved organic carbon based on enzymatic microbiosensors.
Biomarkers of Contaminant Exposure in Chub (Leuciscus cephalus L.) – Biomonitoring of Major Rivers in the Czech Republic
Authors: Havelkova Marcela , Blahova Jana , Kroupova Hana , Randak Tomas , Slatinska Iveta , Leontovycova Drahomira , Grabic Roman , Pospisil Richard , Svobodova Zdenka
Published: December 2008

Biochemical analysis of organisms to assess exposure to environmental contaminants is of great potential use. Biochemical markers, specifically liver enzymes of the first and the second phase of xenobiotic transformation - cytochrome P450 (CYP 450), ethoxyresorufin-O-deethylase (EROD), glutathione-S-transferase (GST) and tripeptide reduced glutathione (GSH) - were used to assess contamination of the aquatic environment at 12 locations near the mouths of major rivers in the Czech Republic. These rivers were the Lužnice, Otava, Sázava, Berounka, Vltava, Labe, Ohře, Svratka, Dyje, Morava and Odra. The indicator species selected was the Chub (Leuciscus cephalus L.). The highest levels of CYP 450 and EROD catalytic activity were found in livers of fish from the Labe (Obříství) (0.32±0.10 nmol mg-1 protein and 1061.38±545.51 pmol min-1 mg-1 protein, respectively). The highest levels of GST catalytic activity and GSH content were found in fish from the Otava (35.39±13.35 nmol min-1 mg-1 protein and 4.29±2.10 nmol GSH mg-1 protein, respectively). They were compared with levels of specific inductors of these biochemical markers in muscle. The results confirmed contamination of some river locations (Labe Obříství, Svratka).
High Sensitivity MEMS Strain Sensor: Design and Simulation
Authors: Mohammed Ahmed A. S. , Moussa Walied A. , Lou Edmond
Published: December 2008

In this article, we report on the new design of a miniaturized strain microsensor. The proposed sensor utilizes the piezoresistive properties of doped single crystal silicon. Employing the Micro Electro Mechanical Systems (MEMS) technology, high sensor sensitivities and resolutions have been achieved. The current sensor design employs different levels of signal amplifications. These amplifications include geometric, material and electronic levels. The sensor and the electronic circuits can be integrated on a single chip, and packaged as a small functional unit. The sensor converts input strain to resistance change, which can be transformed to bridge imbalance voltage. An analog output that demonstrates high sensitivity (0.03mV/me), high absolute resolution (1μe) and low power consumption (100μA) with a maximum range of ±4000μe has been reported. These performance characteristics have been achieved with high signal stability over a wide temperature range (±50oC), which introduces the proposed MEMS strain sensor as a strong candidate for wireless strain sensing applications under harsh environmental conditions. Moreover, this sensor has been designed, verified and can be easily modified to measure other values such as force, torque…etc. In this work, the sensor design is achieved using Finite Element Method (FEM) with the application of the piezoresistivity theory. This design process and the microfabrication process flow to prototype the design have been presented.
CMOS Humidity Sensor System Using Carbon Nitride Film as Sensing Materials
Authors: Lee Sung Pil , Lee Ji Gong , Chowdhury Shaestagir
Published: December 2008

An integrated humidity sensor system with nano-structured carbon nitride film as humidity sensing material is fabricated by a 0.8 μm analog mixed CMOS process. The integrated sensor system consists of differential humidity sensitive field effect transistors (HUSFET), temperature sensor, and operational amplifier. The process contains two poly, two metal and twin well technology. To form CNx film on Si3N4/Si substrate, plasma etching is performed to the gate area as well as trenches. CNx film is deposited by reactive RF magnetron sputtering method and patterned by the lift-off technique. The drain current is proportional to the dielectric constant, and the sensitivity is 2.8 ㎂/%RH.
Multidirectional Scanning Model, MUSCLE, to Vectorize Raster Images with Straight Lines
Authors: Karas Ismail , Bayram Bulent , Batuk Fatmagul , Akay Abdullah , Baz Ibrahim
Published: December 2008

This paper presents a new model, MUSCLE (Multidirectional Scanning for Line Extraction), for automatic vectorization of raster images with straight lines. The algorithm of the model implements the line thinning and the simple neighborhood methods to perform vectorization. The model allows users to define specified criteria which are crucial for acquiring the vectorization process. In this model, various raster images can be vectorized such as township plans, maps, architectural drawings, and machine plans. The algorithm of the model was developed by implementing an appropriate computer programming and tested on a basic application. Results, verified by using two well known vectorization programs (WinTopo and Scan2CAD), indicated that the model can successfully vectorize the specified raster data quickly and accurately.
Downscaling Thermal Infrared Radiance for Subpixel Land Surface Temperature Retrieval
Authors: Liu Desheng , Pu Ruiliang
Published: December 2008

Land surface temperature (LST) retrieved from satellite thermal sensors often consists of mixed temperature components. Retrieving subpixel LST is therefore needed in various environmental and ecological studies. In this paper, we developed two methods for downscaling coarse resolution thermal infrared (TIR) radiance for the purpose of subpixel temperature retrieval. The first method was developed on the basis of a scale-invariant physical model on TIR radiance. The second method was based on a statistical relationship between TIR radiance and land cover fraction at high spatial resolution. The two methods were applied to downscale simulated 990-m ASTER TIR data to 90-m resolution. When validated against the original 90-m ASTER TIR data, the results revealed that both downscaling methods were successful in capturing the general patterns of the original data and resolving considerable spatial details. Further quantitative assessments indicated a strong agreement between the true values and the estimated values by both methods.
Intercomparison of Evapotranspiration Over the Savannah Volta Basin in West Africa Using Remote Sensing Data
Authors: Opoku-Duah S. , Donoghue D. N.M. , Burt T. P.
Published: December 2008

This paper compares evapotranspiration estimates from two complementary satellite sensors – NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS) and ESA’s ENVISAT Advanced Along-Track Scanning Radiometer (AATSR) over the savannah area of the Volta basin in West Africa. This was achieved through solving for evapotranspiration on the basis of the regional energy balance equation, which was computationally-driven by the Surface Energy Balance Algorithm for Land algorithm (SEBAL). The results showed that both sensors are potentially good sources of evapotranspiration estimates over large heterogeneous landscapes. The MODIS sensor measured daily evapotranspiration reasonably well with a strong spatial correlation (R2=0.71) with Landsat ETM+ but underperformed with deviations up to ~2.0 mm day-1, when compared with local eddy correlation observations and the Penman-Monteith method mainly because of scale mismatch. The AATSR sensor produced much poorer correlations (R2=0.13) with Landsat ETM+ and conventional ET methods also because of differences in atmospheric correction and sensor calibration over land.
Anatomical and histochemical characterization of extrafloral nectaries of Prockia crucis (Salicaceae)
Authors: Thadeo Marcela , Cassino Mariana F. , Vitarelli Narah C. , Azevedo Aristéa A. , Araújo João M. , Valente Vânia M. M. , Meira Renata M. S. A.
Published: December 2008

Besides being vital tools in taxonomic evaluation, the anatomy of plant secretory structures and the chemical composition of their secretions may contribute to a more thorough understanding of the roles and functions of these secretory structures. Here we used standard techniques for plant anatomy and histochemistry to examine secretory structures on leaves at different stages of development of Prockia crucis, to evaluate the origin and development of the structures, and to identify the disaccharides and monosaccharides in the exudates. Fructose, glucose, and sucrose constituted up to 49.6% of the entire secretion. The glands were confirmed to be extrafloral nectaries (EFNs); this is the first report of their presence in the genus Prockia. These EFNs are globular, sessile glands, with a central concavity occurring on the basal and marginal regions of the leaf. The epidermis surrounding the concavity is secretory, forming a single‐layered palisade that strongly reacts with periodic acid–Schiff's reagent (PAS) and xylidine Ponceau, indicators of total polysaccharides and total proteins, respectively, in the exudate. On the basis of the similarity of these glands to the salicoid teeth in Populus and Salix, we suggest that these three taxa are phylogenetically close.
Prevalence of common mental disorders and their work consequences in france, according to occupational category
Authors: Cohidon Christine , Imbernon Ellen , Goldberg Marcel
Published: December 2008

In the previously published version of this article Marcel Goldberg name was misspelled within the authorship as Marcel Gorldberg. The corrected version, Marcel Goldberg, appears above to amend the record.
Instandsetzung von Rissen in Stahlbetonbauteilen nach einer außergewöhnlichen Einwirkung
Authors: Fuchs Maximilian , Keuser Manfred
Published: December 2008

Außergewöhnliche Einwirkungen – wie z. B. Erdbeben und Stoßbeanspruchungen, die durch Fahrzeuganprall oder durch Druckund Stoßwellen infolge von Detonationen verursacht werden – führen i. d. R. zu lokalen Schädigungen in Stahlbetonbauteilen. Sowohl der Schadensbewertung als auch der Instandsetzung von geschädigten Stahlbetonbauteilen kommt im Hinblick auf eine dauerhafte Nutzung der Infrastruktur große Bedeutung zu.

Eine mögliche Instandsetzung des Schadens, der durch eine außergewöhnliche Einwirkung hervorgerufen wurde, ist Gegenstand der Untersuchungen. Aufgrund der in einem derartigen Falle nicht wiederkehrenden Rissursache liegt eine Wiederherstellung des monolithischen Bauteilgefüges durch kraftschlüssiges Verbinden der Rissufer mittels Injektion als mögliche Instandsetzungsmaßnahme nahe. Um Kenntnis über die Auswirkungen einer derartigen Rissinjektion auf das Verhalten von geschädigten Stahlbetonbauteilen zu erlangen, wurden zunächst Grundlagenversuche an ausgewählten Probekörpern, die jeweils einen Ausschnitt aus einem geschädigten Bauteil darstellen, durchgeführt. Darauf aufbauend wurden Versuche zur praktischen Anwendung an Stahlbetonplatten, die durch Kontaktdetonation geschädigt waren, durchgeführt. Der Beitrag schließt mit einer Diskussion zur praktischen Anwendbarkeit für die Instandsetzung von Stahlbetonbauteilen nach außergewöhnlicher Einwirkung.
Essential oils analysis in dried materials and granulates obtained from Thymus vulgaris L., Salvia officinalis L., Mentha piperita L. and Chamomilla recutita L.
Authors: Kowalski Radosław , Wawrzykowski Jacek
Published: December 2008

The aim of the research was to evaluate the influence of herbal raw materials granulation on changes in the content and composition of essential oil. The following ground materials and granulates were subjected to analysis: Thymi Herba (Thymus vulgaris L.), Salviae Herba (Salvia officinalis L.), Menthae Piperitae Herba (Mentha piperita L.) and Chamomillae Anthodium (Chamomilla recutita L.). Studies revealed that granulation of raw materials causes an increase in the final product density. i.e. for C. recutita it increased about 4.0‐fold, for S. officinalis about 3.4‐fold, for T. vulgaris about 2.6‐fold, and for M. piperita about 1.6‐fold. Moreover, granulation negatively affected the essential oil content in the evaluated raw materials, resulting in the following losses: about 56.6% for T. vulgaris, about 73.6% for S. officinalis, about 71.3% for M. piperita and about 43.9% for C. recutita. Furthermore, significant changes in the composition of essential oils isolated from granulates were observed with reference to ground materials, e.g. the percentage of iso‐menthol in oil achieved from M. piperita granulate increased from about 29% to about 40%, that of camphor in oil from S. officinalis granulate was 14% in relation to about 8%, and that of thymol in oil from T. vulgaris granulate increased from about 44% to about 67%, whereas the percentage of α‐bisabolol oxide A in oil from C. recutita granulate decreased from about 34% to about 18%. Copyright © 2008 John Wiley & Sons, Ltd.
Oral facial clefts and gene polymorphisms in metabolism of folate/one‐carbon and vitamin A: a pathway‐wide association study
Authors: Boyles Abee L. , Wilcox Allen J. , Taylor Jack A. , Shi Min , Weinberg Clarice R. , Meyer Klaus , Fredriksen Åse , Ueland Per Magne , Johansen Anne Marte W. , Drevon Christian A. , Jugessur Astanand , Trung Truc Nguyen , Gjessing Håkon K. , Vollset Stein Emil , Murray Jeffrey C. , Christensen Kaare , Lie Rolv T.
Published: December 2008

An increased risk of facial clefts has been observed among mothers with lower intake of folic acid or vitamin A around conception. We hypothesized that the risk of clefts may be further moderated by genes involved in metabolizing folate or vitamin A. We included 425 case‐parent triads in which the child had either cleft lip with or without cleft palate (CL/P) or cleft palate only (CPO), and no other major defects. We analyzed 108 SNPs and one insertion in 29 genes involved in folate/one‐carbon metabolism and 68 SNPs from 16 genes involved in vitamin A metabolism. Using the Triad Multi‐Marker (TRIMM) approach we performed SNP, gene, chromosomal region, and pathway‐wide association tests of child or maternal genetic effects for both CL/P and CPO. We stratified these analyses on maternal intake of folic acid or vitamin A during the periconceptional period.

As expected with this high number of statistical tests, there were many associations with P‐values<0.05; although there were fewer than predicted by chance alone. The strongest association in our data (between fetal FOLH1 and CPO, P=0.0008) is not in agreement with epidemiologic evidence that folic acid reduces the risk of CL/P in these data, not CPO. Despite strong evidence for genetic causes of oral facial clefts and the protective effects of maternal vitamins, we found no convincing indication that polymorphisms in these vitamin metabolism genes play an etiologic role. Genet. Epidemiol. 2009. © 2008 Wiley Liss, Inc.
A critical evaluation of genomic control methods for genetic association studies
Authors: Dadd Tony , Weale Michael E. , Lewis Cathryn M.
Published: December 2008

Population stratification is an important potential confounder of genetic case‐control association studies. For replication studies, limited availability of samples may lead to imbalanced sampling from heterogeneous populations. Genomic control (GC) can be used to correct χ2 test statistics which are presumed to be inflated by a factor λ; this may be estimated by a summary χ2 value (λmedian or λmean) from a set of unlinked markers. Many studies applying GC methods have used fewer than 50 unlinked markers and an important question is whether this can adequately correct for population stratification. We assess the behavior of GC methods in imbalanced case‐control studies using simulation. SNPs are sampled from two subpopulations with intra‐continental levels of FST (≤0.005) and sampling schemata ranging from balanced to completely imbalanced between subpopulations. The sampling properties of λmedian and λmean are explored using 6–1,600 unlinked markers to estimate Type 1 error and power empirically. GC corrections based on the χ2‐distribution (GCmedian or GCmean) can be anti‐conservative even when more than 100 single nucleotide polymorphisms (SNPs) are genotyped and realistic levels of population stratification exist. The GCF procedure performs well over a wider range of conditions, only becoming anti‐conservative at low levels of α and with fewer than 25 SNPs genotyped. A substantial loss of power can arise when population stratification is present, but this is largely independent of the number of SNPs used. A literature survey shows that most studies applying GC have used GCmedian or GCmean, rather than GCF, which is the most appropriate GC correction method. Genet. Epidemiol. 2009. © 2008 Wiley Liss, Inc.
A comparison of principal component analysis and factor analysis strategies for uncovering pleiotropic factors
Authors: Wang Xiaojing , Kammerer Candace M. , Anderson Stewart , Lu Jiang , Feingold Eleanor
Published: December 2008

Principal component analysis (PCA) and factor analysis (FA) are often used to uncover genetic factors that contribute to complex disease phenotypes. The purpose of such an analysis is to distill a genetic signal from a large number of correlated phenotype measurements. That signal can then be used in genetic analyses (e.g. linkage analysis), presumably leading to greater success at finding genes than one would achieve with any one raw trait. Although both PCA and FA have been used this way, there has been no comparison of their performance in the literature. We compared the ability of these two procedures to extract unobserved underlying genetic components from complex simulated data on nuclear families. We first simulated seven underlying genetic and environmentally determined traits. Then we derived two sets of 50 complex (observed) traits using algebraic combinations of the underlying components. We next performed PCA and FA on the complex traits. We assessed two aspects of the performance of the methods: (1) ability to detect the underlying genetic components; (2) whether the methods worked better when applied to raw traits or to residuals (after regressing out significant environmental covariates). Our results indicate that both the methods behave similarly in most cases, although FA generally produced factors that had stronger correlations with the underlying traits. We also found that using residuals in PCA or FA analyses greatly increased the probability that the PCs or factors detected common genetic components instead of common environmental factors, except if there was statistical interaction between genetic and environmental factors. Genet. Epidemiol. 2009. © 2008 Wiley‐Liss, Inc.
Allelic‐based gene‐gene interaction associated with quantitative traits
Authors: Jung Jeesun , Sun Bin , Kwon Deukwoo , Koller Daniel L. , Foroud Tatiana M.
Published: December 2008

Recent studies have shown that quantitative phenotypes may be influenced not only by multiple single nucleotide polymorphisms (SNPs) within a gene but also by the interaction between SNPs at unlinked genes. We propose a new statistical approach that can detect gene‐gene interactions at the allelic level which contribute to the phenotypic variation in a quantitative trait. By testing for the association of allelic combinations at multiple unlinked loci with a quantitative trait, we can detect the SNP allelic interaction whether or not it can be detected as a main effect. Our proposed method assigns a score to unrelated subjects according to their allelic combination inferred from observed genotypes at two or more unlinked SNPs, and then tests for the association of the allelic score with a quantitative trait. To investigate the statistical properties of the proposed method, we performed a simulation study to estimate type I error rates and power and demonstrated that this allelic approach achieves greater power than the more commonly used genotypic approach to test for gene‐gene interaction. As an example, the proposed method was applied to data obtained as part of a candidate gene study of sodium retention by the kidney. We found that this method detects an interaction between the calcium‐sensing receptor gene (CaSR), the chloride channel gene (CLCNKB) and the Na, K, 2Cl cotransporter gene (CLC12A1) that contributes to variation in diastolic blood pressure. Genet. Epidemiol. 2009. © 2008 Wiley‐Liss, Inc.
A simple and effective method for cancer immunotherapy by inactivated allogeneic leukocytes infusion
Authors: Su Xiaosan , Guo Sujuan , Zhou Chunxia , Wang Dongmei , Ma Wenbo , Zhang Shuren
Published: December 2008

Allogeneic mixed leukocytes reaction has been reported to activate vast numbers of T lymphocytes and produce large amounts of type 1 cytokines that are linked to an initiation of antitumor immunity. Using poor immunogeneic B16‐F10 and Lewis lung carcinoma (LLC) tumor model, we evaluated the effects of inactivated allogeneic leukocytes infusion (ALI) on the generation of antitumor immune response, as well as its effect on the primary and metastatic tumor. Allogeneic response promoted the generation of both specific and nonspecific antitumor immunity in an in vitro mixed lymphocytes‐tumor cell culture system. Introveinous infusion of mitotically inactivated allogeneic leukocytes resulted in increased type‐1 cytokines (including IL‐2 and IFN‐γ) release, proliferation of various lymphocyte subsets, and generation of both specific and nonspecific antitumor immune response. As a result of such immune response, ALI caused a delayed tumor growth and a prolonged survival in established B16‐F10 melanoma model. In LLC pulmonary spontaneous metastases model, ALI treatment significantly reduced postoperative tumor metastasis as the lung weights were far smaller than control group (0.16 vs. 0.34 g). Furthermore, after primary tumor resection and ALI treatment, 62.5% mice obtained long‐term survival (>120 days) and there were no tumor growths in these mice when they were rechallenged with the same tumor. These experiments demonstrate that inactivated ALI could activate innate and adoptive antitumor immune response. It would be a simple, effective and secured method for cancer immunotherapy. © 2008 Wiley‐Liss, Inc.
Dietary intakes of mushrooms and green tea combine to reduce the risk of breast cancer in Chinese women
Authors: Zhang Min , Huang Jian , Xie Xing , Holman C. D'Arcy J.
Published: December 2008

To investigate effects of dietary mushrooms and joint effects of mushrooms and green tea on breast cancer, a case–control study was conducted in southeast China in 2004–2005. The incident cases were 1,009 female patients aged 20–87 years with histologically confirmed breast cancer. The 1,009 age‐matched controls were healthy women randomly recruited from outpatient breast clinics. Information on frequency and quantity of dietary intake of mushrooms and tea consumption, usual diet, and lifestyle were collected by face‐to‐face interview using a validated and reliable questionnaire. Compared with nonconsumers, the Odds ratios (Ors) were 0.36 (95% CI = 0.25–0.51) and 0.53 (0.38–0.73) for daily intake of ≥10 g fresh mushrooms and ≥4 g dried mushrooms, based on multivariate logistic regression analysis adjusting for established and potential confounders. There were dose–response relationships with significant tests for trend (p < 0.001). The inverse association was found in both pre‐ and postmenopausal women. Compared with those who consumed neither mushrooms nor green tea, the ORs were 0.11 (0.06–0.20) and 0.18 (0.11–0.29) for daily high intake of fresh and dried mushrooms combined with consuming beverages made from ≥1.05 g dried green tea leaves per day. The corresponding linear trends were statistically significant for joint effect (p < 0.001). We conclude that higher dietary intake of mushrooms decreased breast cancer risk in pre‐ and postmenopausal Chinese women and an additional decreased risk of breast cancer from joint effect of mushrooms and green tea was observed. More research is warranted to examine the effects of dietary mushrooms and mechanism of joint effects of phytochemicals on breast cancer. © 2008 Wiley‐Liss, Inc.