bluuebunny/crossref_metadata_2025 huggingface dataset:
Status and Prospects for Combined GPS LOD and VLBI UT1 Measurements
Authors: Senior K. , Kouba J. , Ray J.
Published: November 2010

Status and Prospects for Combined GPS LOD and VLBI UT1 Measurements

A Kalman filter was developed to combine VLBI estimates of UT1-TAI with biased length of day (LOD) estimates from GPS. The VLBI results are the analyses of the NASA Goddard Space Flight Center group from 24-hr multi-station observing sessions several times per week and the nearly daily 1-hr single-baseline sessions. Daily GPS LOD estimates from the International GNSS Service (IGS) are combined with the VLBI UT1-TAI by modeling the natural excitation of LOD as the integral of a white noise process (i.e., as a random walk) and the UT1 variations as the integration of LOD, similar to the method described by Morabito et al. (1988). To account for GPS technique errors, which express themselves mostly as temporally correlated biases in the LOD measurements, a Gauss-Markov model has been added to assimilate the IGS data, together with a fortnightly sinusoidal term to capture errors in the IGS treatments of tidal effects. Evaluated against independent atmospheric and oceanic axial angular momentum (AAM + OAM) excitations and compared to other UT1/LOD combinations, ours performs best overall in terms of lowest RMS residual and highest correlation with (AAM + OAM) over sliding intervals down to 3 d. The IERS 05C04 and Bulletin A combinations show strong high-frequency smoothing and other problems. Until modified, the JPL SPACE series suffered in the high frequencies from not including any GPS-based LODs. We find, surprisingly, that further improvements are possible in the Kalman filter combination by selective rejection of some VLBI data. The best combined results are obtained by excluding all the 1-hr single-baseline UT1 data as well as those 24-hr UT1 measurements with formal errors greater than 5 μs (about 18% of the multi-baseline sessions). A rescaling of the VLBI formal errors, rather than rejection, was not an effective strategy. These results suggest that the UT1 errors of the 1-hr and weaker 24-hr VLBI sessions are non-Gaussian and more heterogeneous than expected, possibly due to the diversity of observing geometries used, other neglected systematic effects, or to the much shorter observational averaging interval of the single-baseline sessions. UT1 prediction services could benefit from better handling of VLBI inputs together with proper assimilation of IGS LOD products, including using the Ultra-rapid series that is updated four times daily with 15 hr delay.
Dynamical Modeling and Excitation Reconstruction as Fundamental of Earth Rotation Prediction
Authors: Zotov L.
Published: November 2010

Dynamical Modeling and Excitation Reconstruction as Fundamental of Earth Rotation Prediction

Though pure mathematical approximations such as regression models and neural networks show good results in Earth rotation forecasting, dynamical modeling remains the only base for the physically meaningful prediction. That assumes the knowledge of cause-effect relationships and physical model of the rotating Earth. Excitation reconstruction from the observed Earth orientation parameters (EOP) is a crucial stage, needed for comparison with known causes, such as tidal forcing, atmospheric (AAM), oceanic (OAM) angular momentum changes, and uncovering unknown ones. We demonstrate different approaches, which can be used to avoid ill-conditionality and amplification of noises during the inversion. We present amplitude and phase studies of the model and reconstructed excitations of Chandler wobble. We found out, that modulation of Chandler excitation is synchronous with 18-yr tidal effects in the Earth's rotation rate changes. The results of the study can be used for excitation and EOP forecast. The key issues of the EOP prediction are discussed.
From Probate Inventories to a Data Set for the History of the Consumer Society
Authors: Schuurman Anton , Pastoor Gabriël
Published: November 2010

In this article we present a set of computer applications for handling (probate) inventories. The programs have been developed at the Department of Rural History within the framework of aresearch programme for the history of consumption in the Netherlands: the MatCult Project. This project studies the development of consumer behaviour in the Netherlands from the sixteenth to the twentieth century. Special attention is given to regional and to town-country differences. The main sources are probate inventories.

After a short overview of the history of the use of computers in inventory research, the Dbase TVapplications MatStore and MatCode are discussed. These programs allow the researcher to be flexible, detailed and economic. Firstly, the information from the inventories is stored as literally as possible in the computer. Secondly, this input is encoded and adapted for analysis using general statistical packages. Thus the programs provide a research tool that is capable of analysing inventories from different periods and locations and that allows international comparisons.
α-Synuclein and DJ-1 as Potential Biological Fluid Biomarkers for Parkinson’s Disease
Authors: Waragai Masaaki , Sekiyama Kazunari , Sekigawa Akio , Takamatsu Yoshiki , Fujita Masayo , Hashimoto Makoto
Published: November 2010

Parkinson’s disease (PD) is the most common form of movement disorder and affects approximately 4% of the population aged over 80 years old. Currently, PD cannot be prevented or cured, and no single diagnostic biomarkers are available. Notably, recent studies suggest that two familial PD-linked molecules, α-synuclein and DJ-1, are present in cerebrospinal fluid (CSF) and that their levels may be altered during the progression of PD. In this regard, sensitive and accurate methods for evaluation of α-synuclein and DJ-1 levels in the CSF and blood have been developed, and the results suggest that the levels of both molecules are significantly decreased in the CSF in patients with PD compared with age-matched controls. Furthermore, specific detection and quantification of neurotoxic oligometric forms of α-synuclein in the blood using enzyme-linked immunosorbent assays might be expected as potential peripheral biomarkers for PD, although further validation is required. Currently, neither α-synuclein nor DJ-1 is satisfactory as a single biomarker for PD, but combinatory evaluation of these biological fluid molecules with other biomarkers and imaging techniques may provide reliable information for diagnosis of PD.
A Molecular–Structure Hypothesis
Authors: Boeyens Jan C. A.
Published: November 2010

The self-similar symmetry that occurs between atomic nuclei, biological growth structures, the solar system, globular clusters and spiral galaxies suggests that a similar pattern should characterize atomic and molecular structures. This possibility is explored in terms of the current molecular structure-hypothesis and its extension into four-dimensional space-time. It is concluded that a quantum molecule only has structure in four dimensions and that classical (Newtonian) structure, which occurs in three dimensions, cannot be simulated by quantum-chemical computation.
Palm Date Fibers: Analysis and Enzymatic Hydrolysis
Authors: Shafiei Marzieh , Karimi Keikhosro , Taherzadeh Mohammad J.
Published: November 2010

Waste palm dates were subjected to analysis for composition and enzymatic hydrolysis of their flesh fibers. The fruit contained 32% glucose and 30% fructose, while the water-insoluble fibers of its flesh consisted of 49.9% lignin and 20.9% polysaccharides. Water-insoluble fibers were settled to 55% of its initial volume in 12 h. The presence of skin and flesh colloidal fibers results in high viscosity and clogging problems during industrial processes. The settling velocity of the fibers was improved by enzymatic hydrolysis. Hydrolysis resulted in 84.3% conversion of the cellulosic part of the fibers as well as reducing the settling time to 10 minutes and the final settled volume to 4% of the initial volume. It implies easier separation of the fibers and facilitates fermentation processes in the corresponding industries. Two kinds of high- and low-lignin fibers were identified from the water-insoluble fibers. The high-lignin fibers (75% lignin) settled easily, while the low-lignin fibers (41.4% lignin) formed a slurry suspension which settled very slowly. The hydrophilicity of these low-lignin fibers is the major challenge of the industrial processes.
Antioxidative Peptides Derived from Enzyme Hydrolysis of Bone Collagen after Microwave Assisted Acid Pre-Treatment and Nitrogen Protection
Authors: Lin Yun-Jian , Le Guo-Wei , Wang Jie-Yun , Li Ya-Xin , Shi Yong-Hui , Sun Jin
Published: November 2010

This study focused on the preparation method of antioxidant peptides by enzymatic hydrolysis of bone collagen after microwave assisted acid pre-treatment and nitrogen protection. Phosphoric acid showed the highest ability of hydrolysis among the four other acids tested (hydrochloric acid, sulfuric acid and/or citric acid). The highest degree of hydrolysis (DH) was 9.5% using 4 mol/L phosphoric acid with a ratio of 1:6 under a microwave intensity of 510 W for 240 s. Neutral proteinase gave higher DH among the four protease tested (Acid protease, neutral protease, Alcalase and papain), with an optimum condition of: (1) ratio of enzyme and substrate, 4760 U/g; (2) concentration of substrate, 4%; (3) reaction temperature, 55 °C and (4) pH 7.0. At 4 h, DH increased significantly (P < 0.01) under nitrogen protection compared with normal microwave assisted acid pre-treatment hydrolysis conditions. The antioxidant ability of the hydrolysate increased and reached its maximum value at 3 h; however DH decreased dramatically after 3 h. Microwave assisted acid pre-treatment and nitrogen protection could be a quick preparatory method for hydrolyzing bone collagen.
Myricetin Protects Cells against Oxidative Stress-Induced Apoptosis via Regulation of PI3K/Akt and MAPK Signaling Pathways
Authors: Kang Kyoung Ah , Wang Zhi Hong , Zhang Rui , Piao Mei Jing , Kim Ki Cheon , Kang Sam Sik , Kim Young Woo , Lee Jongsung , Park Deokhoon , Hyun Jin Won
Published: November 2010

Recently, we demonstrated that myricetin exhibits cytoprotective effects against H2O2-induced cell damage via its antioxidant properties. In the present study, myricetin was found to inhibit H2O2-induced apoptosis in Chinese hamster lung fibroblast (V79-4) cells, as shown by decreased apoptotic bodies, nuclear fragmentation, sub-G1 cell population, and disruption of mitochondrial membrane potential (Dym), which are increased in H2O2-treated cells. Western blot data showed that in H2O2-treated cells, myricetin increased the level of Bcl-2, which is an anti-apoptotic factor, and decreased the levels of Bax, active caspase-9 and -3, which are pro-apoptotic factors. And myricetin inhibited release of cytochrome c from mitochondria to cytosol in H2O2-treated cells. Myricetin-induced survival correlated with Akt activity, and the rescue of cells by myricetin treatment against H2O2-induced apoptosis was inhibited by the specific PI3K (phosphoinositol-3-kinase) inhibitor. Myricetin-mediated survival also inhibited the activation of p38 mitogen activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK), which are members of MAPK. Our studies suggest that myricetin prevents oxidative stress-induced apoptosis via regulation of PI3K/Akt and MAPK signaling pathways.
1,1’,1’’,1’’’-[Porphyrin-5,10,15,20-tetrayltetrakis(3,1-phenylenemethylene)]tetraquinolinium Tetrabromide
Authors: Ishikawa Yoshinobu , Yamashita Takeshi , Fujii Satoshi , Uno Tadayuki
Published: November 2010

Cationic porphyrins interact strongly with guanine quadruplex DNA (G-quadruplex). We herein report the preparation of a cationic porphyrin bearing quinolinium side arms, 1,1’,1’’,1’’’-[porphyrin-5,10,15,20-tetrayltetrakis(3,1-phenylenemethylene)]­tetra­quinolinium tetrabromide (mQu), as a potential G-quadruplex ligand.
Catalytic CVD Synthesis of Carbon Nanotubes: Towards High Yield and Low Temperature Growth
Authors: Magrez Arnaud , Seo Jin Won , Smajda Rita , Mionić Marijana , Forró László
Published: November 2010

The catalytic chemical vapor deposition (CCVD) is currently the most flexible and economically attractive method for the growth of carbon nanotubes. Although its principle is simple, the precisely controlled growth of carbon nanotubes remains very complex because many different parameters influence the growth process. In this article, we review our recent results obtained on the synthesis of carbon nanotubes via CCVD. We discuss the role of the catalyst and the catalyst support. Our recent results obtained from the water assisted growth and the equimolar C2H2-CO2 reaction are also discussed. Both procedures lead to significantly enhanced carbon nanotube growth. In particular, the latter allows growing carbon nanotubes on diverse substrate materials at low temperatures.
Transparent Conducting Oxides for Photovoltaics: Manipulation of Fermi Level, Work Function and Energy Band Alignment
Authors: Klein Andreas , Körber Christoph , Wachau André , Säuberlich Frank , Gassenbauer Yvonne , Harvey Steven P. , Proffit Diana E. , Mason Thomas O.
Published: November 2010

Doping limits, band gaps, work functions and energy band alignments of undoped and donor-doped transparent conducting oxides Zn0, In2O3, and SnO2 as accessed by X-ray and ultraviolet photoelectron spectroscopy (XPS/UPS) are summarized and compared. The presented collection provides an extensive data set of technologically relevant electronic properties of photovoltaic transparent electrode materials and illustrates how these relate to the underlying defect chemistry, the dependence of surface dipoles on crystallographic orientation and/or surface termination, and Fermi level pinning.
Verrucisidinol and Verrucosidinol Acetate, Two Pyrone-Type Polyketides Isolated from a Marine Derived Fungus, Penicillium aurantiogriseum
Authors: Yu Ke , Ren Biao , Wei Junli , Chen Caixia , Sun Jinsheng , Song Fuhang , Dai Huanqin , Zhang Lixin
Published: November 2010

The new secondary metabolites verrucosidinol (1) and its derivative verrucosidinol acetate (2), together with a potent neurotoxin verrucosidin (3), a congener norverrucosidin (4) and a mixture of two known phytotoxic metabolites terrestric acids (5 and 6), were isolated from the marine derived fungus Penicillium aurantiogriseum. Verrucosidinol has a ring-opened ethylene oxide moiety in the polyene α-pyrone skeleton, and verrucosidinol acetate is its acetate derivative. The chemical structures were determined by comparing with literature data and a combination of spectroscopic techniques, including high resolution mass spectrum and two-dimentional nuclear magnetic resonance spectroscopic analysis.
The Knoevenagel-Doebner Reaction on 1,2-O-(2,2,2-Trichloroethylidene) Derivatives of D-Gluco- and D-Manno- furanose
Authors: Kök Gökhan , Karayıldırım Tamer , Ay Kadir , Ay Emriye
Published: November 2010

The synthesis of new α,β-unsaturated furanuronic acid derivatives of α-gluco- (3), β-gluco- (6) and β-manno-chloraloses (9) via a convenient one pot procedure using the Knoevenagel-Doebner reaction approach are described. The dialdofuranose derivatives were reacted with malonic acid under Knoevenagel-Doebner reaction conditions and (E)-α,β-unsaturated furanuronic acid derivatives were obtained.
Application of Phosphine-Phosphite Ligands in the Iridium Catalyzed Enantioselective Hydrogenation of 2-Methylquinoline
Authors: Rubio Miguel , Pizzano Antonio
Published: November 2010

The hydrogenation of 2-methylquinoline with Ir catalysts based on chiral phosphine-phosphites has been investigated. It has been observed that the reaction is very sensitive to the nature of the ligand. Optimization of the catalyst, allowed by the highly modular structure of these phosphine-phosphites, has improved the enantioselectivity of the reaction up to 73% ee. The influence of additives in this reaction has also been investigated. Contrary to the beneficial influence observed in related catalytic systems, iodine has a deleterious effect in the present case. Otherwise, aryl phosphoric acids produce a positive impact on catalyst activity without a decrease on enantioselectivity.
Farnesol, a Potential Efflux Pump Inhibitor in Mycobacterium smegmatis
Authors: Jin Jing , Zhang Ji-Yu , Guo Na , Sheng Hui , Li Lei , Liang Jun-Chao , Wang Xue-Lin , Li Yang , Liu Ming-Yuan , Wu Xiu-Ping , Yu Lu
Published: November 2010

The active multidrug efflux pump (EP) has been described as one of the mechanisms involved in the natural drug resistance of bacteria, such as mycobacteria. As a result, the development of efflux pumps inhibitors (EPIs) is an important topic. In this study, a checkerboard synergy assay indicated that farnesol both decreased the minimum inhibitory concentration (MIC) of ethidium bromide (EtBr) 8-fold against Mycobacterium smegmatis (M. smegmatis) mc2155 ATCC 700084 when incorporated at a concentration of 32 μg/mL (FICI = 0.625) and decreased MIC 4-fold at 16 μg/mL (FICI = 0.375). Farnesol also showed synergism when combined with rifampicin. A real-time 96-well plate fluorometric method was used to assess the ability of farnesol to inhibit EPs in comparison withfour positive EPIs: chlorpromazine, reserpine, verapamil, and carbonyl cyanide m-chlorophenylhydrazone (CCCP). Farnesol significantly enhanced the accumulation of EtBr and decreased the efflux of EtBr in M. smegmatis; these results suggest that farnesol acts as an inhibitor of mycobacterial efflux pumps.
Multiple Routes to Oestrogen Antagonism
Authors: Glover Hilary R. , Barker Stewart , Malouitre Sylvanie D. M. , Puddefoot John R. , Vinson Gavin P.
Published: November 2010

Several lines of evidence attest to the existence of alternative ligand binding sites on the oestrogen receptor (ER), including non-competitive inhibition by trilostane or tamoxifen. It is possible that the inhibitory action of conventional oestrogen agonists at high concentrations may indicate that they too interact at alternative ER sites, albeit at low affinity. To test this possibility an oestrogen reporter assay was used to compare the activity of different oestrogens and antagonists in breast cancer and prostate cell lines. All four cell lines tested contained different amounts of oestrogen receptor α (ERα), ERβ, progesterone receptor and coregulator mRNA. Though differences were observed in response to stimulation and inhibition, these correlated only with the presence or absence of ERα, and not with the other components. Thus stimulation of the reporter by oestradiol and oestrone was biphasic in the breast cancer cells, while prostate cells were unable to respond. Only T47D cells were stimulated by oestriol or diethylstilboestrol, however reporter activity of all the cell lines was repressed by 10mM diethylstilboestrol. Reporter activity of MCF-7 cells was inhibited by tamoxifen, raloxifene and ICI 182,780, but stimulated by trilostane, yet all these antioestrogens inhibited agonist-stimulated activity. Trilostane also inhibited the agonism seen in cells co-treated with E2 and tamoxifen. It is clear that several of the compounds tested may have either agonist or antagonist effects under different conditions and at different concentrations, acting through ERα alone. Though biphasic dose response curves, or hormesis, have been attributed to various mechanisms, we here provide evidence that alternative ligand binding sites may contribute to this phenomenon.
Spotlight on Human LL-37, an Immunomodulatory Peptide with Promising Cell-Penetrating Properties
Authors: Seil Michèle , Nagant Carole , Dehaye Jean-Paul , Vandenbranden Michel , Lensink Marc Ferdinand
Published: November 2010

Cationic antimicrobial peptides are major components of innate immunity and help control the initial steps of the infectious process. They are expressed not only by immunocytes, but also by epithelial cells. They share an amphipathic secondary structure with a polar cationic site, which explains their tropism for prokaryote membranes and their hydrophobic site contributing to the destructuration of these membranes. LL-37 is the only cationic antimicrobial peptide derived from human cathelicidin. LL-37 can also cross the plasma membrane of eukaryotic cells, probably through special domains of this membrane called lipid rafts. This transfer could be beneficial in the context of vaccination: the activation of intracellular toll-like receptors by a complex formed between CpG oligonucleotides and LL-37 could conceivably play a major role in the building of a cellular immunity involving NK cells.
Periodate Oxidation of Methylcellulose: Characterization and Properties of Oxidized Derivatives
Authors: Rinaudo Marguerite
Published: November 2010

In this paper, the behavior of oxidized methylcelluloses is compared with that of the initial methylcellulose, an amphiphilic cellulose derivative. Methylcelluloses are important for many applications in the cosmetic and food industries. The mechanism of thermo-gelation of methylcellulose is briefly explained as well as the method of oxidation of polysaccharides. Then, our experiments involve the preparation of oxidized methylcelluloses: three degrees of oxidation are prepared and the new polymers are characterized by NMR, IR, SEC and rheology. Oxidation with periodate theoretically allows introduction of two aldehydic groups on C2–C3 glycol positions of anhydroglucose units. This reaction not only enhances the flexibility of the cellulosic backbone, but also causes a decrease in the molecular weight. In particular, the rheological behavior of methylcellulose and oxidized methylcellulose as a function of temperature is examined. The oxidized methylcelluloses prepared, being rich in aldehyde functions, become interesting intermediaries to prepare new cellulose derivatives. In this paper, three examples of reductive amination based on the reaction of modified methylcelluloses and −NH2 groups of different molecules are described: β-alanine produces a polyelectrolyte; chitosan and hyaluronan-ADH (derivative obtained with adipic dihydrazide allowing introduction of −NH2 functions on HA backbone) are crosslinked and give new biocompatible hydrogels.
The Santa Clara Strength of Religious Faith Questionnaire: Assessing Faith Engagement in a Brief and Nondenominational Manner
Authors: Plante Thomas G.
Published: November 2010

The Santa Clara Strength of Religious Faith Questionnaire is a brief (10-item, or five-item short form version), reliable and valid self report measure assessing strength of religious faith and engagement suitable for use with multiple religious traditions, denominations, and perspectives. It has been used in medical, student, psychiatric, substance abuse, and among general populations nationally and internationally and among multiple cultures and languages. Brief non denominational self report measures of religious and faith engagement that have demonstrated reliability and validity are not common but can have potential for general utility in both clinical and research settings. This article provides an overview of the scale and current research findings regarding its use in both research and clinical practice.
Theory and Applications of Surface Plasmon Resonance, Resonant Mirror, Resonant Waveguide Grating, and Dual Polarization Interferometry Biosensors
Authors: Daghestani Hikmat N. , Day Billy W.
Published: November 2010

Biosensors have been used extensively in the scientific community for several purposes, most notably to determine association and dissociation kinetics, protein-ligand, protein-protein, or nucleic acid hybridization interactions. A number of different types of biosensors are available in the field, each with real or perceived benefits over the others. This review discusses the basic theory and operational arrangements of four commercially available types of optical biosensors: surface plasmon resonance, resonant mirror, resonance waveguide grating, and dual polarization interferometry. The different applications these techniques offer are discussed from experiments and results reported in recently published literature. Additionally, recent advancements or modifications to the current techniques are also discussed.
Remote Sensing of Ecology, Biodiversity and Conservation: A Review from the Perspective of Remote Sensing Specialists
Authors: Wang Kai , Franklin Steven E. , Guo Xulin , Cattet Marc
Published: November 2010

Remote sensing, the science of obtaining information via noncontact recording, has swept the fields of ecology, biodiversity and conservation (EBC). Several quality review papers have contributed to this field. However, these papers often discuss the issues from the standpoint of an ecologist or a biodiversity specialist. This review focuses on the spaceborne remote sensing of EBC from the perspective of remote sensing specialists, i.e., it is organized in the context of state-of-the-art remote sensing technology, including instruments and techniques. Herein, the instruments to be discussed consist of high spatial resolution, hyperspectral, thermal infrared, small-satellite constellation, and LIDAR sensors; and the techniques refer to image classification, vegetation index (VI), inversion algorithm, data fusion, and the integration of remote sensing (RS) and geographic information system (GIS).
An Analytical Model of Joule Heating in Piezoresistive Microcantilevers
Authors: Ansari Mohd Zahid , Cho Chongdu
Published: November 2010

The present study investigates Joule heating in piezoresistive microcantilever sensors. Joule heating and thermal deflections are a major source of noise in such sensors. This work uses analytical and numerical techniques to characterise the Joule heating in 4-layer piezoresistive microcantilevers made of silicon and silicon dioxide substrates but with the same U-shaped silicon piezoresistor. A theoretical model for predicting the temperature generated due to Joule heating is developed. The commercial finite element software ANSYS Multiphysics was used to study the effect of electrical potential on temperature and deflection produced in the cantilevers. The effect of piezoresistor width on Joule heating is also studied. Results show that Joule heating strongly depends on the applied potential and width of piezoresistor and that a silicon substrate cantilever has better thermal characteristics than a silicon dioxide cantilever.
Measuring Relative-Story Displacement and Local Inclination Angle Using Multiple Position-Sensitive Detectors
Authors: Matsuya Iwao , Katamura Ryuta , Sato Maya , Iba Miroku , Kondo Hideaki , Kanekawa Kiyoshi , Takahashi Motoichi , Hatada Tomohiko , Nitta Yoshihiro , Tanii Takashi , Shoji Shuichi , Nishitani Akira , Ohdomari Iwao
Published: November 2010

We propose a novel sensor system for monitoring the structural health of a building. The system optically measures the relative-story displacement during earthquakes for detecting any deformations of building elements. The sensor unit is composed of three position sensitive detectors (PSDs) and lenses capable of measuring the relative-story displacement precisely, even if the PSD unit was inclined in response to the seismic vibration. For verification, laboratory tests were carried out using an Xθ-stage and a shaking table. The static experiment verified that the sensor could measure the local inclination angle as well as the lateral displacement. The dynamic experiment revealed that the accuracy of the sensor was 150 µm in the relative-displacement measurement and 100 µrad in the inclination angle measurement. These results indicate that the proposed sensor system has sufficient accuracy for the measurement of relative-story displacement in response to the seismic vibration.
Hydrostatic Pressure Sensing with High Birefringence Photonic Crystal Fibers
Authors: Fávero Fernando C. , Quintero Sully M. M. , Martelli Cicero , Braga Arthur M.B. , Silva Vinícius V. , Carvalho Isabel C. S. , Llerena Roberth W. A. , Valente Luiz C. G.
Published: November 2010

The effect of hydrostatic pressure on the waveguiding properties of high birefringence photonic crystal fibers (HiBi PCF) is evaluated both numerically and experimentally. A fiber design presenting form birefringence induced by two enlarged holes in the innermost ring defining the fiber core is investigated. Numerical results show that modal sensitivity to the applied pressure depends on the diameters of the holes, and can be tailored by independently varying the sizes of the large or small holes. Numerical and experimental results are compared showing excellent agreement. A hydrostatic pressure sensor is proposed and demonstrated using an in-fiber modal interferometer where the two orthogonally polarized modes of a HiBi PCF generate fringes over the optical spectrum of a broad band source. From the analysis of experimental results, it is concluded that, in principle, an operating limit of 92 MPa in pressure could be achieved with 0.0003% of full scale resolution.
A Design of Wireless Sensor Networks for a Power Quality Monitoring System
Authors: Lim Yujin , Kim Hak-Man , Kang Sanggil
Published: November 2010

Power grids deal with the business of generation, transmission, and distribution of electric power. Recently, interest in power quality in electrical distribution systems has increased rapidly. In Korea, the communication network to deliver voltage, current, and temperature measurements gathered from pole transformers to remote monitoring centers employs cellular mobile technology. Due to high cost of the cellular mobile technology, power quality monitoring measurements are limited and data gathering intervals are large. This causes difficulties in providing the power quality monitoring service. To alleviate the problems, in this paper we present a communication infrastructure to provide low cost, reliable data delivery. The communication infrastructure consists of wired connections between substations and monitoring centers, and wireless connections between pole transformers and substations. For the wireless connection, we employ a wireless sensor network and design its corresponding data forwarding protocol to improve the quality of data delivery. For the design, we adopt a tree-based data forwarding protocol in order to customize the distribution pattern of the power quality information. We verify the performance of the proposed data forwarding protocol quantitatively using the NS-2 network simulator.
Adaptive AOA-Aided TOA Self-Positioning for Mobile Wireless Sensor Networks
Authors: Wen Chih-Yu , Chan Fu-Kai
Published: November 2010

Location-awareness is crucial and becoming increasingly important to many applications in wireless sensor networks. This paper presents a network-based positioning system and outlines recent work in which we have developed an efficient principled approach to localize a mobile sensor using time of arrival (TOA) and angle of arrival (AOA) information employing multiple seeds in the line-of-sight scenario. By receiving the periodic broadcasts from the seeds, the mobile target sensors can obtain adequate observations and localize themselves automatically. The proposed positioning scheme performs location estimation in three phases: (I) AOA-aided TOA measurement, (II) Geometrical positioning with particle filter, and (III) Adaptive fuzzy control. Based on the distance measurements and the initial position estimate, adaptive fuzzy control scheme is applied to solve the localization adjustment problem. The simulations show that the proposed approach provides adaptive flexibility and robust improvement in position estimation.
A Dipping Duration Study for Optimization of Anodized-Aluminum Pressure-Sensitive Paint
Authors: Sakaue Hirotaka , Ishii Keiko
Published: November 2010

Anodized-aluminum pressure-sensitive paint (AA-PSP) uses the dipping deposition method to apply a luminophore on a porous anodized-aluminum surface. We study the dipping duration, one of the parameters of the dipping deposition related to the characterization of AA-PSP. The dipping duration was varied from 1 to 100,000 s. The properties characterized are the pressure sensitivity, temperature dependency, and signal level. The maximum pressure sensitivity of 65% is obtained at the dipping duration of 100 s, the minimum temperature dependency is obtained at the duration of 1 s, and the maximum signal level is obtained at the duration of 1,000 s, respectively. Among the characteristics, the dipping duration most influences the signal level. The change in the signal level is a factor of 8.4. By introducing a weight coefficient, an optimum dipping duration can be determined. Among all the dipping parameters, such as the dipping duration, dipping solvent, and luminophore concentration, the pressure sensitivity and signal level are most influenced by the dipping solvent.
Optical Sensing with Simultaneous Electrochemical Control in Metal Nanowire Arrays
Authors: MacKenzie Robert , Fraschina Corrado , Sannomiya Takumi , Auzelyte Vaida , Vörös Janos
Published: November 2010

This work explores the alternative use of noble metal nanowire systems in large-scale array configurations to exploit both the nanowires’ conductive nature and localized surface plasmon resonance (LSPR). The first known nanowire-based system has been constructed, with which optical signals are influenced by the simultaneous application of electrochemical potentials. Optical characterization of nanowire arrays was performed by measuring the bulk refractive index sensitivity and the limit of detection. The formation of an electrical double layer was controlled in NaCl solutions to study the effect of local refractive index changes on the spectral response. Resonance peak shifts of over 4 nm, a bulk refractive index sensitivity up to 115 nm/RIU and a limit of detection as low as 4.5 × 10−4 RIU were obtained for gold nanowire arrays. Simulations with the Multiple Multipole Program (MMP) confirm such bulk refractive index sensitivities. Initial experiments demonstrated successful optical biosensing using a novel form of particle-based nanowire arrays. In addition, the formation of an ionic layer (Stern-layer) upon applying an electrochemical potential was also monitored by the shift of the plasmon resonance.
A Tunable Strain Sensor Using Nanogranular Metals
Authors: Schwalb Christian H. , Grimm Christina , Baranowski Markus , Sachser Roland , Porrati Fabrizio , Reith Heiko , Das Pintu , Müller Jens , Völklein Friedemann , Kaya Alexander , Huth Michael
Published: November 2010

This paper introduces a new methodology for the fabrication of strain-sensor elements for MEMS and NEMS applications based on the tunneling effect in nano-granular metals. The strain-sensor elements are prepared by the maskless lithography technique of focused electron-beam-induced deposition (FEBID) employing the precursor trimethylmethylcyclopentadienyl platinum [MeCpPt(Me)3]. We use a cantilever-based deflection technique to determine the sensitivity (gauge factor) of the sensor element. We find that its sensitivity depends on the electrical conductivity and can be continuously tuned, either by the thickness of the deposit or by electron-beam irradiation leading to a distinct maximum in the sensitivity. This maximum finds a theoretical rationale in recent advances in the understanding of electronic charge transport in nano-granular metals.
Reconciling Groundwater Storage Depletion Due to Pumping with Sustainability
Authors: Van der Gun Jac , Lipponen Annukka
Published: November 2010

Groundwater pumping causes depletion of groundwater storage. The rate of depletion incurred by any new well is gradually decreasing and eventually becomes zero in the long run, after induced recharge and reduction of natural discharge of groundwater combined (capture) have become large enough to balance the pumping rate completely. If aquifer-wide aggregated pumping rates are comparatively large, then such a new dynamic equilibrium may not be reached and groundwater storage may become exhausted. Decisions to pump groundwater are motivated by people’s need for domestic water and by expected benefits of using water for a variety of activities. But how much finally is abstracted from an aquifer (or is considered to be an optimal aggregate abstraction rate) depends on a wide range of other factors as well. Among these, the constraint imposed by the groundwater balance (preventing aquifer exhaustion) has received ample attention in the professional literature. However, other constraints or considerations related to changes in groundwater level due to pumping are observed as well and in many cases they even may dominate the decisions on pumping. This paper reviews such constraints or considerations, examines how they are or may be incorporated in the decision-making process, and evaluates to what extent the resulting pumping rates and patterns create conditions that comply with principles of sustainability.
Ecophysiology of Aspergillus Section Nigri Species Potential Ochratoxin A Producers
Authors: Astoreca Andrea L. , Magnoli Carina E. , Dalcero Ana M.
Published: November 2010

After aflatoxins, ochratoxin A (OTA) is the most studied mycotoxin due to the toxicological significance in human and animal diets. OTA presence has been extensively reported worldwide in the last decade in several agricultural products. The main OTA producer in tropical and temperate climates is Aspergillus carbonarius followed by species belonging to A. niger aggregate. Currently, many scientists worldwide have studied the influence of water activity and temperature for growth and biosynthesis of OTA by these species on synthetic media. This article reviews ecophysiological studies of Aspergillus section Nigri strains on synthetic media and natural substrates. The results of these investigations suggest that significant amounts of OTA can be produced in only five days and that the use of different storage practices, such as aW and temperature levels below 0.930 and 15 °C, respectively, allow controlling fungal contamination and minimizing the OTA production in several products as peanuts, corn, dried grapes and derived products for human consumption.
Snake Venom Disintegrins and Cell Migration
Authors: Selistre-de-Araujo Heloisa S. , Pontes Carmen L. S. , Montenegro Cyntia F. , Martin Ana Carolina B. M.
Published: November 2010

Cell migration is a key process for the defense of pluricellular organisms against pathogens, and it involves a set of surface receptors acting in an ordered fashion to contribute directionality to the movement. Among these receptors are the integrins, which connect the cell cytoskeleton to the extracellular matrix components, thus playing a central role in cell migration. Integrin clustering at focal adhesions drives actin polymerization along the cell leading edge, resulting in polarity of cell movement. Therefore, small integrin-binding proteins such as the snake venom disintegrins that inhibit integrin-mediated cell adhesion are expected to inhibit cell migration. Here we review the current knowledge on disintegrin and disintegrin-like protein effects on cell migration and their potential use as pharmacological tools in anti-inflammatory therapy as well as in inhibition of metastatic invasion.
Total lymphocyte count as a tool for timing opportunistic infection prophylaxis in resource-limited settings: a study from India
Authors: Srirangaraj Sreenivasan , Venkatesha Dasegowda
Published: November 2010

Introduction: In resource-limited settings, due to the high cost of CD4 cell count testing, physicians must decide about opportunistic infection (OI) prophylaxis without a laboratory evaluation of HIV stage and level of immune suppression. This study aimed to evaluate the correlation of total lymphocyte count (TLC), an inexpensive laboratory parameter, to CD4 count, and to determine a range of TLC cut-offs for the initiation of OI prophylaxis that is appropriate for resource-limited settings. Methodology: Spearman correlation between CD4 count and TLC was assessed in patients attending the Anti-Retroviral Therapy (ART) centre at Mysore, India. Positive predictive value (PPV), negative predictive value (NPV), sensitivity, and specificity of various TLC cut-offs were computed for CD4 counts < 200 cells/mm3. Correlation and statistical indices were computed for all patients and for HIV patients with active tuberculosis. Results: Good correlation was noted between the 106 paired TLC and CD4 counts (r = 0.3497).TLC < 1200cells/mm3 had 88.14% sensitivity and 34.78% specificity for CD4 count < 200 cells/mm3. In those patients with active tuberculosis, TLC< 2000cells/mm3 had 95.24% sensitivity and 100% specificity for CD4 count < 200cells/ mm3. Conclusions: TLC could serve as a low-cost tool for determining when to initiate prophylaxis in resource-constrained settings.
Estimating the time period between infection and diagnosis based on CD4+ counts at first diagnosis among HIV-1 antiretroviral naïve patients in Nigeria
Authors: Forbi Joseph C , Forbi Thanda D , Agwale Simon M
Published: November 2010

Introduction: CD4+ T-cell levels are an important criterion for categorizing HIV-related clinical conditions. Late diagnosis of infection contributes to poor medical outcomes and the continuation of viral transmission. This population-based cohort study in north central Nigeria reports the initial CD4+ lymphocyte counts at the time of first HIV diagnosis and determines the approximate time interval when HIV infection was acquired.. Methodology: Confirmed HIV-1 infected individuals (n = 588) for whom the dates of first HIV diagnosis were known were enrolled in this study. CD4+ lymphocyte counts were measured using a Fluorescence Activated Cell Sorter (FACS) platform that automatically quantifies CD4+ lymphocytes as absolute numbers of lymphocytes per μL of blood. The estimated time interval between HIV infection and time of first HIV diagnosis was determined as a function of the CD4+ lymphocytes' decay rate per calendar year. Results: The results showed that 22.1% and 49.7% of HIV-infected individuals present late with advanced (CD4+: 200-349 cells/mL) and severe (CD4+: < 200 cells/mL) immunosuppression respectively, while only 12.1% present with CD4+  500 cells/mL and 16.2%with CD4+ between 350-499 cells/mL. Mean CD4+ counts for females were higher when compared to those of males (p > 0.05), The time interval between HIV infection and first diagnosis was approximately 6.1 years for males and 7.3 years for females. Conclusion: The majority of HIV-infected individuals in this study accessed health care at late stages of infection, suggesting many HIV-infected individuals in Nigeria are unaware of their HIV status. More efficient programs for early diagnosis of HIV to prevent transmission are urgently required.
Multiple contaminations of chickens with Campylobacter, Escherichia coli and Salmonella in Yaounde (Cameroon)
Authors: Nzouankeu Ariane , Ngandjio Antoinette , Ejenguele Guy , Njine Thomas , Ndayo Wouafo Marguerite
Published: November 2010

Introduction: Food-borne diseases associated with Campylobacter, Escherichia coli, and Salmonella are mainly caused by the consumption of raw or undercooked poultry meat. The objective of this study was to evaluate the prevalence of Campylobacter, Escherichia coli, and Salmonella in chickens. Methodology: One hundred and fifty chickens collected from eight retail markets in Yaounde were examined for the presence of Campylobacter, Escherichia coli, and Salmonella using standard bacteriological procedures. Results: Of the 150 chickens collected, 135 (90%) were contaminated with Campylobacter (68.9% C. coli and 31.1% C. jejuni). All the chickens were positive for E. coli. Among the 150 isolates, 17 (11.3%) were enteropathogenic E. coli (EPEC). Additionally, 103 Salmonella strains were recovered from 90 chickens. Salmonella Enteritidis (45.6%) and Salmonella Hadar (28.1%) were the most frequent serotypes. Multiple contamination was found in 142 chickens (94.6%), of which 83 (55.3%) were concurrently contaminated with Campylobacter, Escherichia coli, and Salmonella. Conclusion: These results show that chickens in Cameroon are highly contaminated with Campylobacter, Escherichia coli, and Salmonella. The multiple contaminations of chickens is a potential risk of infection for consumers and highlights the necessity of public awareness for food safety.
Influenza immunization rates, knowledge, attitudes and practices of health care workers in Iran
Authors: Khazaeipour Zahra , Ranjbarnovin Neda , Hoseini Najmesadat
Published: November 2010

Introduction: This study aimed to determine influenza vaccine coverage and evaluate the knowledge, attitudes and practice about influenza and vaccine of health care workers in Tehran, Iran. Methodology: This cross-sectional survey involved 144 health care workers (HCWs) at the Tehran University of Medical Science between October 2008 and February 2009. Participants received a self-administered questionnaire directed at 35 items of knowledge and every correct response was scored one point. Results: Influenza vaccination coverage for the 2008-2009 season was 66.9 % (range, 45% to 62%). Most HCWs (80.6%) had received an influenza vaccination in the past, and 65.4% intended to receive vaccination in the coming year.  The main reason given for being immunized was the effectiveness of the influenza vaccine (51.4%). The main reason given for not being immunized was concern about adverse effects (23.1%). The knowledge score for the 35 items ranged from 0 to 34 (mean 17.37). Mean knowledge scores differed between educational levels. There was no significant difference in mean knowledge scores between females and males (P > 0.05). Independent variables (age, sex, marital status, having children aged ≤ 16 years, educational level) were not significant predictors of taking influenza immunization. Conclusion: Despite the high coverage rate of influenza vaccination in our study, we would expect a higher rate because of free vaccine availability. The results indicate the need for on-going education of influenza disease among HCWs to increase vaccination rates.
Approach to Pandemic 2009 influenza: first report from a main referral hospital for Pandemic H1N1 influenza care in Iran
Authors: Dashti-Khavidaki Simin , Khalili Hossein , Gholamalipour Farid , Soudbakhsh Abdolreza , Talasaz Azita Hajhossein , Hajabdolbaghi Mahboobeh , Rasoolinejad Mehrnaz , Mokhtari Azad Talat , Fathi Mehdi , Talebian Mohammad Taghi , Nasiripour Somayeh
Published: November 2010

Introduction: Pandemic H1N1 influenza A (pdmH1N1) was a major health threat worldwide. Methodology:  A prospective cross-sectional study was conducted at Imam Khomeini Hospital in Iran. Cases of suspicious pdmH1N1 patients referred to the emergency ward of the hospital were enrolled in the study, regardless of whether the final location of treatment was the community, the hospital ward, or the intensive care unit.   Oseltamivir was administered within three hours of the patient's admission.  The median length of stay for hospitalized patients was 3 days. Results:  Gastrointestinal symptoms (nausea [164/434; 37.8%] and vomiting [98/434; 22.6%]) were the most common adverse reactions to oseltamivir in the study population, followed by dizziness (74/434; 17.1%). Out of 434 patients, 209 (48.2%) were treated in the community, 201 (46.3%) were admitted to the general ward in the hospital, and 24 (5.5%) were admitted to an ICU. Conclusions: This study provided insight on the effectiveness of oseltamivir in treating pandemic influenza A, as well as possible adverse reactions to the drug.  The study further drew attention to a variety of pdmH1N1 complications, in particular secondary bacterial pneumonia. We also determined that 2009 influenza A (H1N1) infection-related critical illness and mortality affected fewer elderly than younger patients. Additionally, it was shown that our approach to patients with suspected Influenza A/H1N1 virus in our hospital was compatible with World Health Organization pandemic flu guidelines in our country.