bluuebunny/crossref_metadata_2025_split huggingface dataset:
Solution combustion synthesis of metal nanopowders: Copper and copper/nickel alloys
Authors: Kumar A. , Wolf E. E. , Mukasyan A. S. 
Published: December 2010

AbstractBased on a general methodology for the preparation of metal–nanopowders by solution combustion synthesis (SCS), the reaction pathways for SCS of pure copper and copper–nickel alloy nanopowders are investigated. It is confirmed that the necessary condition for SCS of metals in a metal‐nitrate oxidizer–glycine system is the property of the oxidizer to decompose with formation of HNO3 species. In this case, for compositions with excess of glycine, a hydrogen reducing atmosphere develops in the reaction front, leading to the formation of reduced metals. The proposed reaction pathways are supported by X‐ray diffraction analysis of the quenched samples and DTA–TGA studies of the Cu(NO3)2·6H2O–glycine and Ni(NO3)2·6H2O/Cu(NO3)2·6H2O–glycine systems. The results show that the formation of Cu2O and CuO oxide phases takes place at early stages in the reaction front followed by their reduction to pure Cu phase in the postcombustion zones. However, in a Cu–Ni alloy, a fraction of intermetallic Cu–Ni phase appeared directly in the combustion front, whereas the rest of the oxygen‐free alloy formed through reduction of oxide phases. © 2011 American Institute of Chemical Engineers AIChE J, 2011
Transformation of hemipentahydrate to monohydrate of risedronate monosodium by seed crystallization in solution
Authors: Nguyen Thi Nhat Phuong , Kim Kwang‐Joo 
Published: December 2010

AbstractThe transformation from a hemipentahydrate to a monohydrate of risedronate monosodium was studied by seed crystallization in solution. By using the in‐line measurement based on ultrasonic measuring technique and the off‐line measurements such as optical microscopic and crystallography, transformation of hydrate forms and crystallization of monohydrate were observed. The effect of concentration of solution and solid fraction of suspension on the ultrasonic velocity was found. The hydrate composition, concentration of solution, and supersaturation during the transformation were estimated with elapsed time. The effect of monohydrate seed, agitation rate and temperature on the induction time, transformation, and crystallization was also investigated. Eventually, transformation from hemipentahydrates to monohydrates and crystallization of monohydrate were analyzed successfully from in‐line measuring technique. © 2011 American Institute of Chemical Engineers AIChE J, 2011
Brief communication: Developmental dysplasia of the hip in medieval London
Authors: Mitchell Piers D. , Redfern Rebecca C. 
Published: December 2010

AbstractDevelopmental dysplasia of the hip (DDH) is a spectrum of disease starting in childhood and in many cases persisting into adulthood. The spectrum ranges from acetabular dysplasia, through hip subluxation to dislocation. The aim of this research was to determine the prevalence and pathoanatomy of acetabular dysplasia and subluxation in excavated human skeletal remains, to complement past research on dislocation in DDH. The material under study was the medieval cemetery of St. Mary Spital in London, in use from c.1100 to 1539 AD. A series of 572 adults with both hips preserved were analyzed. Acetabular dysplasia was indicated by a shallow acetabulum with upward sloping roof. Subluxation was suggested by degenerative change along the margin of the acetabulum suggestive of labral tears, and degenerative change in the outer part of the acetabular roof suggestive of osteoarthritis. The prevalence of DDH (acetabular dysplasia, subluxation, or dislocation) was 1.7%. Because this a congenital musculoskeletal disorder of relatively high frequency, with significant variation in prevalence between populations around the world, it is a topic that warrants targeted research from physical anthropologists studying past populations. Am J Phys Anthropol, 2011. © 2010 Wiley‐Liss, Inc.
Relationship between canine dimorphism and mandibular morphology in the hamadryas baboon and the Japanese monkey
Authors: Fukase Hitoshi 
Published: December 2010

AbstractTo examine morphological interrelationships between canine size and mandibular corpus shape, inter‐sex comparisons were made in the hamadryas baboon and the Japanese monkey, known to display extreme and moderate canine dimorphism, respectively. Results of adult comparisons showed that all mandibular dimensions were significantly larger in the males than in the females in both species. In the hamadryas baboon, the males also exhibited a higher ratio of anterior to posterior corpus height than the females. This sex difference in corpus shape was not significant in the Japanese monkey, indicating lack of involvement of canine dimorphism. Analysis of mandibular growth patterns in the hamadryas baboon demonstrated that significant sexual size difference did not occur before incisor eruption, and that the anteriorly high corpus of the adult male mandible was associated with a rapidly increasing symphyseal height after incisor eruption. It was also shown that the female canine started to erupt shortly after incisor eruption, while the forming male canine continued to stay near the mandibular base and developed further in size until eruption. The relative positions of the incisors keptshifting upwards even after eruption in the males, while they hardly changed in the females. It is therefore suggested that the prolonged development and size increase of the male canine is accompanied by further enlargement of the symphysis, resulting in the higher anterior corpus of the adult males compared to the adult females. The results thus indicate the importance of understanding the spatial relationships of the developing teeth in interpreting mandibular morphology. Am J Phys Anthropol, 2011. © 2010 Wiley‐Liss, Inc.
Influence of hydrophobic tail on the adsorption of isomeric alcohols at air/water interface
Authors: Le T. N. , Phan C. M. , Ang H. M. 
Published: December 2010

ABSTRACTThis study investigated the influence of molecular structures of alcohols on adsorption behaviour. The adsorption isotherm of nonanols, octanols and hexanols at air–water interface was determined using the Wilhelmy plate method, in combination with an automatic dispenser. The experimental data were fitted with Frumkin–Langmuir isotherms by applying least‐squares techniques in Solver (MS Excel) to identify the adsorption parameters. These parameters can be used to quantify and compare the surface behaviours of all the investigated surfactants. It has been found that with the same concentration, the straight chain alcohols had stronger surface activity than the corresponding branched alcohols. The adsorption activity was also strongly related to the position of the hydroxyl group, with primary alcohols showing strongest adsorption. Overall, it was found that the surface activity decreased with increasing bulkiness of the alcohol structure. The results also highlighted the significance of low concentration data in determining the adsorption isotherm of alcohols. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd.
Atomic absorption spectrometric determination of cadmium and lead in soil after total digestion
Authors: Naeem Kashif , Yawar Wasim , Akhter Perveen , Rehana Ishrat 
Published: December 2010

ABSTRACTTo establish the baseline levels of cadmium (Cd) and lead (Pb) in Pakistani soil, samples were collected from various ecological areas of the country. A total digestion procedure using an acid mixture of HFHClO4 was investigated for heavy metal analysis of soil samples. Concentrations of these elements were measured using flame and graphite furnace atomic absorption spectrometry. Measured elemental contents of Cd and Pb varied from 0.41–1.18 and 22.47–95.75 µg/g with geometric mean 0.73 and 47.99 and geometric standard deviation concentrations of 1.36 and 1.65 µg/g, respectively. Two certified reference materials (IAEA Soil‐7 and IAEA‐405 estuarine sediment) were introduced for the validation of analytical data. The estimated values were compared with other regions of the world and found lower than the world average values, Cd 27% and Pb 13%, and therefore considered comparatively safe and may not be a cause of concern for environmental pollution. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd.
Effect of bis‐triazoles on a ribose‐based fluorescent sensor
Authors: Huang Huei‐Jyun , Fang Hau‐Yu , Chir Jiun‐Ly , Wu An‐Tai 
Published: December 2010

ABSTRACTWe synthesized two ribosyl‐based fluorescent sensors. Both sensors have an anthracene as the fluorophore, but they differ in the recognition site for metal ions. One (3) has two ribosyl esters, and the other (6) has two triazole groups linked to two ribosyl esters. Among the metal ions examined in MeOH, compound 3 displayed a large chelation‐enhanced fluorescence (CHEF) effect with Hg2+ and Cu2+ ions, and compound 6 displayed a large chelation‐quenched fluorescence (CHQF) effect with Cu2+ and Ni2+ ions. The results demonstrated that the absence (sensor 3) and presence (sensor 6) of an incorporated bis‐triazole group in a ribosyl‐based fluorescent sensor conferred different preferences and distinct binding modes for metal ions. Copyright © 2010 John Wiley & Sons, Ltd.
Cathodic electrochemiluminescent behavior of luminol at nafion–nano‐TiO2 modified glassy carbon electrode
Authors: Ye Ruihong , Huang Lizhang , Qiu Bin , Song Ziwang , Lin Zhenyu , Chen Guonan 
Published: December 2010

ABSTRACTThe electrochemiluminescence (ECL) behavior of luminol on a nafion–nano‐TiO2 modified glassy carbon electrode (nafion–nano‐TiO2GCE) was studied. Two ECL peaks (ECL‐1 and ECL‐2) were found during cathodic potential scanning. ECL‐1 at ca −0.4 V (vs AgAgCl reference electrode) came from the reaction between luminol and active oxygen anion produced at the GCE surface directly, while ECL‐2 at ca −0.9 V (vs AgAgCl reference electrode) came from the reaction between luminol and the active oxygen anion catalyzed by TiO2. The possible mechanism for the generation of both ECL peaks has been proposed. The reproducibility of the ECL intensities on nafion–nano‐TiO2GCE at ECL‐1 and ECL‐2 was good, with relative standard deviations (n = 10) of 4.3 and 1.3%, respectively. The ECL‐2 generated at the nafion–nano‐TiO2GCE surface was further developed to detect the dissolved oxygen, and a detection limit of 0.02 mg/L was achieved. The proposed method was applied to detect dissolved oxygen in water with satisfactory result. Copyright © 2010 John Wiley & Sons, Ltd.
Marrow‐Derived stem cell motility in 3D synthetic scaffold is governed by geometry along with adhesivity and stiffness
Authors: Peyton Shelly R. , Kalcioglu Z. Ilke , Cohen Joshua C. , Runkle Anne P. , Van Vliet Krystyn J. , Lauffenburger Douglas A. , Griffith Linda G. 
Published: December 2010

AbstractDesign of 3D scaffolds that can facilitate proper survival, proliferation, and differentiation of progenitor cells is a challenge for clinical applications involving large connective tissue defects. Cell migration within such scaffolds is a critical process governing tissue integration. Here, we examine effects of scaffold pore diameter, in concert with matrix stiffness and adhesivity, as independently tunable parameters that govern marrow‐derived stem cell motility. We adopted an “inverse opal” processing technique to create synthetic scaffolds by crosslinking poly(ethylene glycol) at different densities (controlling matrix elastic moduli or stiffness) and small doses of a heterobifunctional monomer (controlling matrix adhesivity) around templating beads of different radii. As pore diameter was varied from 7 to 17 µm (i.e., from significantly smaller than the spherical cell diameter to approximately cell diameter), it displayed a profound effect on migration of these stem cells—including the degree to which motility was sensitive to changes in matrix stiffness and adhesivity. Surprisingly, the highest probability for substantive cell movement through pores was observed for an intermediate pore diameter, rather than the largest pore diameter, which exceeded cell diameter. The relationships between migration speed, displacement, and total path length were found to depend strongly on pore diameter. We attribute this dependence to convolution of pore diameter and void chamber diameter, yielding different geometric environments experienced by the cells within. Bioeng. 2011; 108:1181–1193. © 2010 Wiley Periodicals, Inc.
Escherichia coli W as a new platform strain for the enhanced production of L‐Valine by systems metabolic engineering
Authors: Park Jin Hwan , Jang Yu‐Sin , Lee Jeong Wook , Lee Sang Yup 
Published: December 2010

AbstractA less frequently employed Escherichia coli strain W, yet possessing useful metabolic characteristics such as less acetic acid production and high L‐valine tolerance, was metabolically engineered for the production of L‐valine. The ilvA gene was deleted to make more pyruvate, a key precursor for L‐valine, available for enhanced L‐valine biosynthesis. The lacI gene was deleted to allow constitutive expression of genes under the tac or trc promoter. The ilvBNmut genes encoding feedback‐resistant acetohydroxy acid synthase (AHAS) I and the L‐valine biosynthetic ilvCED genes encoding acetohydroxy acid isomeroreductase, dihydroxy acid dehydratase, and branched chain amino acid aminotransferase, respectively, were amplified by plasmid‐based overexpression. The global regulator Lrp and L‐valine exporter YgaZH were also amplified by plasmid‐based overexpression. The engineered E. coli W (ΔlacI ΔilvA) strain overexpressing the ilvBNmut, ilvCED, ygaZH, and lrp genes was able to produce an impressively high concentration of 60.7 g/L L‐valine by fed‐batch culture in 29.5 h, resulting in a high volumetric productivity of 2.06 g/L/h. The most notable finding is that there was no other byproduct produced during L‐valine production. The results obtained in this study suggest that E. coli W can be a good alternative to Corynebacterium glutamicum and E. coli K‐12, which have so far been the most efficient L‐valine producer. Furthermore, it is expected that various bioproducts including other amino acids might be more efficiently produced by this revisited platform strain of E. coli. Bioeng. 2011; 108:1140–1147. © 2010 Wiley Periodicals, Inc.
Enzyme inactivation by ethanol and development of a kinetic model for thermophilic simultaneous saccharification and fermentation at 50 °C with Thermoanaerobacterium saccharolyticum ALK2
Authors: Podkaminer Kara K. , Shao Xiongjun , Hogsett David A. , Lynd Lee R. 
Published: December 2010

AbstractStudies were undertaken to understand phenomena operative during simultaneous saccharification and fermentation (SSF) of a model cellulosic substrate (Avicel) at 50°C with enzymatic hydrolysis mediated by a commercial cellulase preparation (Spezyme CP) and fermentation by a thermophilic bacterium engineered to produce ethanol at high yield, Thermoanaerobacterium saccharolyticum ALK2. Thermal inactivation at 50°C, as shown by the loss of 50% of enzyme activity over 4 days in the absence of ethanol, was more severe than at 37°C, where only 25% of enzyme activity was lost. In addition, at 50°C ethanol more strongly influenced enzyme stability. Enzyme activity was moderately stabilized between ethanol concentrations of 0 and 40 g/L, but ethanol concentrations above 40 g/L accelerated enzyme inactivation, leading to 75% loss of enzymatic activity in 80 g/L ethanol after 4 days. At 37°C, ethanol did not show a strong effect on the rate of enzyme inactivation. Inhibition of cellulase activity by ethanol, measured at both temperatures, was relatively similar, with the relative rate of hydrolysis inhibited 50% at ethanol concentrations of 56.4 and 58.7 g/L at 50 and 37°C, respectively. A mathematical model was developed to test whether the measured phenomena were sufficient to quantitatively describe system behavior and was found to have good predictive capability at initial Avicel concentrations of 20 and 50 g/L. Biotechnol. Bioeng. 2011; 108:1268–1278. © 2010 Wiley Periodicals, Inc.
Modeling industrial centrifugation of mammalian cell culture using a capillary based scale‐down system
Authors: Westoby Matthew , Rogers Jameson K. , Haverstock Ryan , Romero Jonathan , Pieracci John 
Published: December 2010

AbstractContinuous‐flow centrifugation is widely utilized as the primary clarification step in the recovery of biopharmaceuticals from cell culture. However, it is a challenging operation to develop and characterize due to the lack of easy to use, small‐scale, systems that can be used to model industrial processes. As a result, pilot‐scale continuous centrifugation is typically employed to model large‐scale systems requiring a significant amount of resources. In an effort to reduce resource requirements and create a system which is easy to construct and utilize, a capillary shear device, capable of producing energy dissipation rates equivalent to those present in the feed zones of industrial disk stack centrifuges, was developed and evaluated. When coupled to a bench‐top, batch centrifuge, the capillary device reduced centrate turbidity prediction error from 37% to 4% compared to using a bench‐top centrifuge alone. Laboratory‐scale parameters that are analogous to those routinely varied during industrial‐scale continuous centrifugation were identified and evaluated for their utility in emulating disk stack centrifuge performance. The resulting relationships enable bench‐scale process modeling of continuous disk stack centrifuges using an easily constructed, scalable, capillary shear device coupled to a typical bench‐top centrifuge. Bioeng. 2011; 108:989–998. © 2010 Wiley Periodicals, Inc.
Development and validation of an analytical method for determination of endocrine disruptor, 2,4‐D, in paddy field water
Authors: Park Ji‐Yeon , Choi Jeong‐Heui , Abd El‐Aty A. M. , Kim Bo Mi , Park Jong‐Hyouk , Choi Woo Jung , Shim Jae‐Han 
Published: December 2010

AbstractThe acidic herbicides are an important class of chemical compounds that are used to control a variety of weeds that threaten many crops. Owing to their low microbial activity levels, the acidic herbicides exhibit a residual activity remaining for periods of up to several months in soils and water. The principal objective of this study was to develop an analytical method based on liquid–liquid and solid‐phase extraction followed by HPLC, for the determination of 2,4‐D in paddy field water. The residues were verified via tandem mass spectrometry (MS/MS) in negative‐ion electrospray ionization (ESI) mode. Linearity was good over a concentration range of 1–100 µg/L with a correlation coefficient (r2) of 0.999. The mean recovery rates of triplicate results ranged from 85.2 to 90.85%. The limits of detection and quantitation were 0.4 and 1.0 µg/L, respectively. The method proposed herein was applied to field samples acquired from Hampyung and Sunchang counties, Republic of Korea. The analyte was detected at a concentration range of 6.8–12.8 and 3.55–24.0 µg/L, respectively. Copyright © 2010 John Wiley & Sons, Ltd.
In search of the psychopathic sexuality taxon: Indicator size does matter
Authors: Walters Glenn D. , Marcus David K. , Edens John F. , Knight Raymond A. , Sanford Glenn M. 
Published: December 2010

AbstractRecent research has suggested that a qualitatively distinct subtype of psychopathic sex offender can be identified via taxometric analyses (Harris et al., 2007). In this study we attempted to replicate the hypothesized psychopathic sexuality taxon in a group of 503 male sexual offenders using data from the Psychopathy Checklist‐Revised (PCL‐R: Hare, 2003) and five coercive and precocious sexuality items. Ambiguous to dimensional results were obtained when, in a replication of the Harris et al. (2007) study, dichotomized indicators were analyzed with summed input maximum covariance (MAXCOV). Clearly dimensional results, however, were obtained when higher correlating and more valid quasi‐continuous indicators were analyzed with traditional (input variables not summed) MAXCOV, and both dichotomous and quasi‐continuous indicators were analyzed with mean above minus below a cut (MAMBAC) and latent‐mode factor analysis (L‐Mode). These results suggest that Harris et al. (2007) may have mistaken the random fluctuations of weakly correlating and poorly differentiating indicators for a taxon. Consistent with the vast majority of earlier research, our results suggest that psychopathy (with or without coercive and precocious sexuality) is a dimensional construct. Copyright © 2010 John Wiley & Sons, Ltd.
Autotest: An educational software application to support teachers in creating tests
Authors: Hernández‐Del‐Olmo Félix , Gaudioso Elena 
Published: December 2010

AbstractIn this paper, we present the students' evaluation procedure at the UNED (Spanish Distance Education University). At UNED, students are free to choose the location and the date they take their exams. However, this approach requires that teachers define and develop several exams for every single subject. To ease this task, in this paper we present Autotest, a tool that generates exams in an automatic way. We instantiate this tool for a subject being taught by the authors, Complexity and Computability taught in the third year of the Computer Science studies at UNED. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 636–640, 2013
Adaptive distance learning and testing system
Authors: Marković Suzana , Jovanović Zoran , Jovanović Nenad , Jevremović Aleksandar , Popović Ranko 
Published: December 2010

AbstractUser models are essential to e‐learning systems, giving students learning continuity, tutors evidence of students' progress, and both a way to personalize students' learning materials to their abilities and preferences. Personalizing information has long been the motivation behind developing e‐learning systems. Adaptive educational systems attempt to maintain a learning style profile for each student and use this profile to adapt the presentation and navigation of instructional content to each student. This kind of system adapts the learning process on the basis of the student's learning preferences, knowledge, and availability. One such Web‐based tool is built at the Business School of Professional Studies in Blace (the system of intelligent evaluation using tests), which infers student knowledge using adaptive testing. The knowledge is not evaluated according to fixed standards, but it depends on individual characteristics of each student, therefore, the learning style which is the most suitable. This system is part of the integrated assessment system inside of integrated curriculum. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21:E2–E13, 2013
Analysis and modeling of tutor functions
Authors: Ayachi‐Ghanouchi Sonia , Cheniti‐Belcadhi Lilia , Lewis Robert 
Published: December 2010

AbstractIn distance education and training, tutors play a fundamental role as they act as a facilitator of the learning process, particularly through their evaluation of the progress made. In this paper, we provide an overview of tutoring in e‐learning contexts and describe the main functions that should be assumed by a tutor. We then analyze all activities performed by tutors and establish conceptual models based on the Unified Modeling Language. The models promote an in‐depth analysis and a detailed description of the functions needed to tutor on‐line courses. These models may not only be used as guidelines for tutors but also as a general schema to assess their work. Evaluation and validation of these models have been accomplished by a questionnaire that has been designed and distributed to learners in the framework of a tutored e‐learning experiment. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 657–670, 2013