bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biosensing Paraoxon in Simulated Environmental Samples by Immobilized Organophosphorus Hydrolase in Functionalized Mesoporous Silica
Authors: Lei Chenghong , Valenta Michelle M. , Saripalli K. Prasad , Ackerman Eric J. 
Published: January 2007

ABSTRACTThere is a critical need for highly sensitive, cost‐effective sensors to conduct ecological analyses for environmental and homeland security‐related applications. Enzyme biosensors, which are currently gaining acceptance for environmental monitoring applications, need improvements to deliver faster measurements with stabilized sensing elements, e.g., enzymes. We report here on a method which significantly overcomes this difficulty, and demonstrate its application in a biosensor for aquatic environmental applications. A fast‐responding and stable biosensor was developed via immobilization of organophosphorus hydrolase (OPH) in functionalized mesoporous silica (FMS) with pore sizes in tens of nanometers. The OPH‐FMS composite was held on glassy carbon electrode by a dried Nafion gel and FMS protected OPH from Nafion‐resulted activity loss. The resulting enzyme biosensor, when integrated with an electrochemical instrument, responded rapidly to low paraoxon concentration and achieved steady‐state current in less than 10 s, with a detection limit of 4.0 × 10−7 M paraoxon. The biosensor was tested for detection of paraoxon in simulated environmental samples, under wide‐ranging physicochemical conditions. Results clearly indicate high recovery efficiencies in aqueous solutions (96 to 101%) at different pH, total organic carbon, total dissolved solids, and total suspended solids, and demonstrate the ability of the biosensor unit to continuously monitor paraoxon in aqueous conditions similar to those found in river and lake systems.
Demodex folliculorum in patients with rheumatoid arthritis
Authors: Ciftci Ihsan , Dundar Umit , Cetinkaya Zafer , Kulac Mustafa , Kiyildi Nilay , Turel Aycan , Evcik Deniz , Kavuncu Vural 
Published: January 2007

AbstractThe objective of this study was to investigate the incidence and density of Demodex folliculorum in the patients with rheumatoid arthritis (RA). Forty-one patients with RA and twenty-seven age and sex matched healthy controls were enrolled in this study. Disease Activity Score (DAS 28) was used for the assessment of disease activity. Out of 41 patients, 33 were females and 8 males. The mean disease duration was 10.9 ± 8.2 years. The mean DAS 28 was 3.8 ± 1.2. No statistically significant differences in the incidence and density of Demodex mites were found between patients with RA and controls. Although immunosuppression is thought to be a risk factor for the D. folliculorum infestation no such correlations could be found in the 41 immunosuppressed patients with RA, therefore, further studies with larger groups are needed.
A new case of de novo 11q duplication in a patient with normal development and intelligence and review of the literature
Authors: Zarate Yuri A. , Kogan Jillene M. , Schorry Elizabeth K. , Smolarek Teresa A. , Hopkin Robert J. 
Published: January 2007

AbstractA new case of 11q interstitial duplication is reported in a patient with mild dysmorphic features but normal development. Chromosome analysis revealed a de novo 11q dup(11)(q14.1q21) on G banding and FISH studies. Additional molecular genetic studies revealed a similar but more distal duplication at the level of 11q21q23.1. Previous cases of isolated 11q duplication that overlapped with this case were associated with a wide variety of clinical findings and variable developmental disability. These cases all included additional material not duplicated in this patient. The current case represents the first de novo case of 11q duplication with normal development suggesting that the segment between 11q14.1 and 11q21 contains few genes that are dose sensitive. Review of other cases that have used conventional cytogenetic resolution studies suggests that the band 11q13.5 may contain genes contributing to the developmental disabilities in the cases previously reported with proximal 11q duplication. Differences between conventional cytogenetic techniques and newer molecular genetic studies are expected. These newer techniques will help refine prognosis and counseling for families in the future. © 2007 Wiley‐Liss, Inc.
The impact of time constraints on Internet and Web use
Authors: Slone Debra J. 
Published: January 2007

AbstractThis study examines the influence of time constraints on Internet and Web search goals and search behavior. Specifically, it looks at the searching behavior of public library Internet users who, previously limited to 30 minutes per Internet session, are given an unlimited amount of time for use. Interviews and observations were conducted with 34 participants searching on their own queries. Despite an increase in the time allowed for searching, most people spent less than 30 minutes on the Internet, carrying out tasks like paying bills, shopping, browsing, and making reservations. Those who took more than 30 minutes were looking for jobs or browsing. E‐mail use was universal. In this context, influences like time‐dependent and time‐independent tasks, use of search hubs to perform more efficient searches, and search diversity were recorded. Though there are a number of large and small studies of Internet and Web use, few of them focus on temporal influences. This study extends knowledge in this area of inquiry.
Citation data analysis on hydrogeology
Authors: Schwartz Frank , Fang Y.C. 
Published: January 2007

AbstractThis article explores the status of research in hydrogeology using data mining techniques. First we try to explain what citation analysis is and review some of the previous work on citation analysis. The main idea in this article is to address some common issues about citation numbers and the use of these data. To validate the use of citation numbers, we compare the citation patterns for Water Resources Research papers in the 1980s with those in the 1990s. The citation growths for highly cited authors from the 1980s are used to examine whether it is possible to predict the citation patterns for highly‐cited authors in the 1990s. If the citation data prove to be steady and stable, these numbers then can be used to explore the evolution of science in hydrogeology. The famous quotation, “If you are not the lead dog, the scenery never changes,” attributed to Lee Iacocca, points to the importance of an entrepreneurial spirit in all forms of endeavor. In the case of hydrogeological research, impact analysis makes it clear how important it is to be a pioneer. Statistical correlation coefficients are used to retrieve papers among a collection of 2,847 papers before and after 1991 sharing the same topics with 273 papers in 1991 in Water Resources Research. The numbers of papers before and after 1991 are then plotted against various levels of citations for papers in 1991 to compare the distributions of paper population before and after that year. The similarity metrics based on word counts can ensure that the “before” papers are like ancestors and “after” papers are descendants in the same type of research. This exercise gives us an idea of how many papers are populated before and after 1991 (1991 is chosen based on balanced numbers of papers before and after that year). In addition, the impact of papers is measured in terms of citation presented as “percentile,” a relative measure based on rankings in one year, in order to minimize the effect of time.
Effect of wall shear rate on biofilm deposition and grazing in drinking water flow chambers
Authors: Paris Tony , Skali‐Lami Salaheddine , Block Jean‐Claude 
Published: January 2007

AbstractThe effect of four‐wall shear rates (34.9, 74.8, 142.5, and 194.5 s−1) on bacterial deposition on glass slides in drinking water flow chambers was studied. Biofilm image acquisition was performed over a 50‐day period. Bacterial accumulation and surface coverage curves were obtained. Microscopic observations allowed us to obtain information about the dynamics and spatial distribution of the biofilm. During the first stage of biofilm formation (210–518 h), bacterial accumulation was a function of the wall shear rate: the higher the wall shear rate, the faster the bacterial deposition (1.1 and 1.9 × 104 bacterial cells · cm−2 for wall shear rates of 34.9 and 142.5 s−1, respectively). A new similarity relationship characteristic of a non‐dimensional time and function of the wall shear rate was proposed to describe initial bacterial deposition. After 50 days of exposure to drinking water, surface coverage was more or less identical under the entire wall shear rates (7.44 ± 0.9%), suggesting that biofilm bacterial density cannot be controlled using hydrodynamics. However, the spatial distribution of the biofilm was clearly different. Under low wall shear rate, aggregates were composed of bacterial cells able to “vibrate” independently on the surface, whereas, under a high wall shear rate, aggregates were more cohesive. Therefore, susceptibility to the hydraulic discontinuities occurring in drinking water system may not be similar. In all the flow chambers, significant decreases in bacterial biomass (up to 77%) were associated with the presence of amoebae. This grazing preferentially targeted small, isolated cells. Biotechnol. Bioeng. 2007; 97: 1550–1561. © 2007 Wiley Periodicals, Inc.
Prediction of mass transfer coefficients in non‐Newtonian fermentation media using first‐principles methods
Authors: Radl Stefan , Khinast Johannes G. 
Published: January 2007

AbstractBubble flows in non‐Newtonian fluids were analyzed using first‐principles methods with the aim to compute and predict mass transfer coefficients in such fermentation media. The method we used is a Direct Numerical Simulation (DNS) of the reactive multiphase flow with deformable boundaries and interfaces. With this method, we are able for the first time to calculate mass transfer coefficients in non‐Newtonian liquids of different rheologies without any experimental data. In the current article, shear‐thinning fluids are considered. However, the results provide the basis for further investigations, such as the study of viscoelastic fluids. Biotechnol. Bioeng. 2007; 97: 1329–1334. © 2007 Wiley Periodicals, Inc.
Sulfide oxidation at halo‐alkaline conditions in a fed‐batch bioreactor
Authors: van den Bosch Pim L.F. , van Beusekom Otto C. , Buisman Cees J.N. , Janssen Albert J.H. 
Published: January 2007

AbstractA biotechnological process is described to remove hydrogen sulfide (H2S) from high‐pressure natural gas and sour gases produced in the petrochemical industry. The process operates at halo‐alkaline conditions and combines an aerobic sulfide‐oxidizing reactor with an anaerobic sulfate (SO) and thiosulfate (S2O) reducing reactor. The feasibility of biological H2S oxidation at pH around 10 and total sodium concentration of 2 mol L−1 was studied in gas‐lift bioreactors, using halo‐alkaliphilic sulfur‐oxidizing bacteria (HA‐SOB). Reactor operation at different oxygen to sulfide (O2:H2S) supply ratios resulted in a stable low redox potential that was directly related with the polysulfide (S) and total sulfide concentration in the bioreactor. Selectivity for SO formation decreased with increasing S and total sulfide concentrations. At total sulfide concentrations above 0.25 mmol L−1, selectivity for SO formation approached zero and the end products of H2S oxidation were elemental sulfur (S0) and S2O. Maximum selectivity for S0 formation (83.3±0.7%) during stable reactor operation was obtained at a molar O2:H2S supply ratio of 0.65. Under these conditions, intermediary S plays a major role in the process. Instead of dissolved sulfide (HS−), S seemed to be the most important electron donor for HA‐SOB under S0 producing conditions. In addition, abiotic oxidation of S was the main cause of undesirable formation of S2O. The observed biomass growth yield under SO producing conditions was 0.86 g N mol−1 H2S. When selectivity for SO formation was below 5%, almost no biomass growth was observed. Biotechnol. Bioeng. 2007; 97: 1053–1063. © 2007 Wiley Periodicals, Inc.
Encapsulation of proteins in biodegradable polymeric microparticles using electrospray in the Taylor cone‐jet mode
Authors: Xie Jingwei , Wang Chi‐Hwa 
Published: January 2007

AbstractSolvent extraction (or evaporation from a W1/O/W2‐dispersion), coacervation, and spray drying methods are commonly employed to encapsulate protein drugs in polymeric microparticles for sustained delivery applications. To overcome the limitations of these methods, a novel electrospray method was developed to encapsulate a model protein drug—bovine serum albumin (BSA) in biodegradable polymeric microparticles and examine the feasibility of the process in not denaturing the protein. Microparticles of approximately 20 µm diameter with corrugated surfaces and smooth surfaces were observed by scanning electron microscope. Confocal laser scanning microscope images showed that BSA was distributed evenly in microparticles. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) was employed to investigate the protein integrity of BSA released from the polymer matrix after 38 days. No protein degradation was observed during the 38 days release. The secondary structure of released BSA was characterized by Fourier transform infrared (FTIR) and circular dichroism (CD), which suggested that the released BSA was almost identical to native BSA. The encapsulation efficiency could reach 76% by adjusting the amount of the additive Pluronic F127 and processing parameters. The release profile could be tailored by the fabrication process and the sustained release of BSA could endure for more than 1 month. More than 80% of the bioactivity of BSA (evaluated by BSA ELISA kit) could be maintained after releasing from polymer matrix. Findings of the present study demonstrate that this novel electrospray method is a promising approach to encapsulate bioactive materials such as proteins, enzymes, antibiotics, and DNA fragments in biodegradable polymeric particles. Biotechnol. Bioeng. 2007; 97: 1278–1290. © 2007 Wiley Periodicals, Inc.
Distributed state simulation of endogenous processes in biological wastewater treatment
Authors: Schuler Andrew J. , Jassby David 
Published: January 2007

AbstractDistributed state‐type simulations (based on modeling of individual bacteria as they move through a reactor system) predicted a greater sensitivity of enhanced biological phosphorus removal (EBPR) performance to endogenous degradation than did conventional, “lumped”‐type simulations (based on average biomass compositions). Recent research has indicated that the variable hydraulic residence times experienced by individual microbial storage product accumulating bacteria in systems with completely mixed reactors tend to produce populations with diverse microbial storage product contents (distributed states). Endogenous degradation in EBPR systems is of particular interest because the polyphosphate accumulating organisms (PAOs) responsible for EBPR rely on the accumulation of three different storage products that may be endogenously degraded. Simulations indicated that as endogenous degradation rates of microbial storage products were increased, EBPR performance decreased more rapidly according to the distributed approach than according to the lumped approach. State profile analysis demonstrated that as these rates increased, the population fraction with depleted storage products also increased, and this tended to increase the error in calculated biokinetic rates by the lumped approach. Simulations based on recently reported endogenous rate coefficients also suggested large differences between distributed and lumped predictions of EBPR performance. These results demonstrated that endogenous decay processes may play a more important role in EBPR than predicted by the lumped approach. This suggests a need for further research to determine endogenous process rates, and for incorporation of this information to distributed‐type simulators, as this should lead to improved accuracy of EBPR simulations. Biotechnol. Bioeng. 2007; 97: 1087–1097. © 2007 Wiley Periodicals, Inc.
A simple numerical methodology for BFD problems using stream function vorticity formulation
Authors: Tzirtzilakis E. E. 
Published: January 2007

AbstractThe fundamental problem of biomagnetic fluid dynamics (BFD) in a 2D rectangular channel is numerically studied. The physical problem is described by a coupled, non‐linear system of partial differential equations, with appropriate boundary conditions. For the mathematical formulation, the stream function–vorticity formulation is used and the numerical solution is obtained by developing a pseudotransient numerical technique. A boundary condition for the vorticity is also constructed and grid stretching is used. The efficiency of the method is verified by comparison with other results documented in the literature. New results are also obtained for high values of the magnetic number which is the dominant factor for the determination of the flow field in biomagnetic fluid flow problems. Copyright © 2007 John Wiley & Sons, Ltd.
A simple way to introduce fibers into FEM models
Authors: Vanalli L. , Paccola R. R. , Coda H. B. 
Published: January 2007

AbstractThis communication proposes a simple way to introduce fibers into finite element modelling. This is a promising formulation to deal with fiber‐reinforced composites by the finite element method (FEM), as it allows the consideration of short or long fibers placed arbitrarily inside a continuum domain (matrix). The most important feature of the formulation is that no additional degree of freedom is introduced into the pre‐existent finite element numerical system to consider any distribution of fiber inclusions. In other words, the size of the system of equations used to solve a non‐reinforced medium is the same as the one used to solve the reinforced counterpart. Another important characteristic is the reduced work required by the user to introduce fibers, avoiding ‘rebar’ elements, node‐by‐node geometrical definitions or even complex mesh generation. An additional characteristic of the technique is the possibility of representing unbounded stresses at the end of fibers using a finite number of degrees of freedom. Further studies are required for non‐linear applications in which localization may occur. Along the text the linear formulation is presented and the bounded connection between fibers and continuum is considered. Four examples are presented, including non‐linear analysis, to validate and show the capabilities of the formulation. Copyright © 2007 John Wiley & Sons, Ltd.
Optimization of thermal environment during crystal growth of large‐sized Nd:YAG by Temperature Gradient Technique
Authors: Hongjun Li , Jun Xu , Liangbi Su , Benxue Jiang , Guangjun Zhao , Guoqing Zhou , Yongjun Dong 
Published: January 2007

AbstractA finite‐element model is employed to analysis the thermal environments in Temperature Gradient Technique (TGT) furnace during the growth of large‐sized Nd:YAG crystal. The obtained results show that when the crucible is located at the lower position inside of the heater, a flatter solid‐liquid interface is established, which makes it easier to obtain the core‐free Nd:YAG crystal. Meanwhile, the lower crucible position can induce higher axial temperature gradient, which is beneficial to the release of latent heat. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth and characterization of near stoichiometric LiNbO3 single crystal
Authors: Yao S. H. , Hu X. B. , Wang J. Y. , Liu H. , Gao L. , Cheng X. F. , Yin X. , Chen X. F. 
Published: January 2007

AbstractA near stoichiometric LiNbO3 single crystal has been grown by the Czochralski method from a 58.5% Li melt hold in a large platinum crucible. High resolution X‐ray rocking curves of 30$ \bar 3 $0 and 0006 reflections indicated that the near stoichiometric LiNbO3 crystal possesses the high structural quality. Compared with the congruent LiNbO3, the near stoichiometric LiNbO3 possesses shorter ultraviolet absorption edge, thus higher Li concentration. The OH– infrared absorption band analyses showed that the Li concentration in the near stoichiometric LiNbO3 crystal is higher than that in the congruent LiNbO3 crystal. This result is in good agreement with that of the ultraviolet absorption edge. The electro‐optic (EO) coefficient γ22 of the near stoichiometric LiNbO3 crystal was measured to be 6.75 pm/V higher than that of congruent LiNbO3 crystal. It also proves the near stoichiometric LiNbO3 electro‐optic Q‐switched requires a low driving voltage and it is advantageous for the device performance. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth and characterization of gel grown calcium pyrophosphate tetrahydrate crystals
Authors: Parekh Bharat B. , Joshi Mihir J. 
Published: January 2007

AbstractFormation of calcium pyrophosphate dihydrate (CPPD) crystals in soft tissues such as cartilage, meniscus and synovial tissues lead afflictions. The appearance of these crystals in the synovial fluid give rise to acute arthritis attack, which is known as pseudo‐gout. The growth of calcium pyrophosphate crystals in gel medium can mimic the growth in a body. In the present study, calcium pyrophosphate tetrahydrate (CPPT) crystals are grown by a single diffusion gel growth technique and characterized by powder XRD, FT‐IR spectroscopy, TGA, kinetic and thermodynamic studies of dehydration and dielectric studies. Monoclinic crystals structure, presence of P‐O bonds and four water molecules are confirmed from powder XRD, FT‐IR and TGA studies, respectively. The dielectric investigation suggests the reduction in dielectric constant with increase in frequency. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth of TGS crystals using uniaxially solution‐crystallization method of Sankaranarayanan‐Ramasamy
Authors: Balamurugan N. , Lenin M. , Bhagavannarayana G. , Ramasamy P. 
Published: January 2007

AbstractThe recently discovered crystal growth method called uniaxially solution‐crystallization method of Sankaranarayanan–Ramasamy (SR) is modified in some aspects and used for growth of triglycine sulphate (TGS) crystals. The modification leads to the simplicity, reduction of cost and avoided the temperature fluctuations. The 〈010〉 direction of TGS is very important and used for fabrication of infrared detectors. Using this method, the 〈001〉, 〈010〉 directional crystals of TGS were successfully grown in a glass crystallizer. The grown crystal was characterized by HRXRD, UV‐Visible and dielectric studies. The results prove the suitability of the modified SR method for oriented TGS crystal. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spectroscopic and thermal investigations of poly(vinylidene fluoride) films composites with LaNi3Co2
Authors: Elashmawi I. S. , Elsheshtawi N. A. , Abdelkader H. I. , Hakeem N. A. 
Published: January 2007

AbstractPoly(vinylidene fluoride) (PVDF) and LaNi3Co2 were composites in various combinations by using melting technique. Morphological and physical properties of both the surface and interface of poly(vinylidene fluoride)/ LaNi3Co2 composite films have been investigated. FTIR and XRD diffraction analysis evidenced the increase of α, β and γ‐ PVDF crystalline phases. The bands at 888 and 1414 cm‐1 were assigned to γ‐phase of PVDF. Maximum value of the relative amount of β‐phase was observed at 35 and 60% FL. This result was confirmed by X‐ray diffraction (XRD) and differential scanning calorimetry (DSC) analysis. Maximum value of degree of crystallinity was observed at 15% Filling level (FL). Morphology of SEM consists of two different size rings and spherulites. DSC was used to identify the melting temperature, the order of reaction and the activation energy of melting. A sharp endothermic peak at Tm ≈ 444 K due to melting and T2 ≈ 360 K due to α‐relaxation/transition. Maximum values of magnetoresistance (MR) observed from range (243 to 238K) are due to reorientation of dipoles in a process associated with the glass transition temperature of PVDF. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)