bluuebunny/crossref_metadata_2025_split huggingface dataset:
Autocomplete as Research Tool: A Study on Providing Search Suggestions
Authors: Ward David , Hahn Jim , Feist Kirsten 
Published: December 2012

As the library website and on its online searching tools become the primary “branch” many users visit for their research, methods for providing automated, context-sensitive research assistance need to be developed to guide unmediated searching towards the most relevant results. This study examines one such method, the use of autocompletion in search interfaces, by conducting usability tests on its use in typical academic research scenarios. The study reports notable findings on user preference for autocomplete features, and suggests best practices for their implementation.
The Photo‐Stability of Polymer Solar Cells: Contact Photo‐Degradation and the Benefits of Interfacial Layers
Authors: Williams Graeme , Wang Qi , Aziz Hany 
Published: December 2012

AbstractThe organic/electrode interfaces in organic solar cells are systematically studied for their light, heat, and electrical stability in an inert atmosphere. Various extraction layers are examined for their effect on device stability, including poly(3,4‐ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) and MoO3 for hole extraction layers, as well as LiF, Cs2CO3, and lithium acetylacetonate (Liacac) for electron extraction layers. The organic/metal interface is shown to be inherently photo‐unstable, resulting in significant losses in device efficiency with irradiation. X‐ray photoelectron spectroscopy measurements of the organic/aluminum interface suggest that the photo‐induced changes are chemical in nature. In general, interfacial layers are shown to substantially reduce photo‐degradation of the active layer/electrode interface. In spite of their photo‐stability, several interfacial layers present at the active layer/cathode interface suffer from thermal degradation effects due to temperature increases under exposure to light. Electrical aging effects are proven to be negligible in comparison to other major modes of degradation.
Mammal Hip Morphology and Function: Coxa Recta and Coxa Rotunda
Authors: Bouma Heinse W. , De Boer Stefan F. , De Vos John , Van Kampen Paulien M. , Hogervorst Tom 
Published: December 2012

AbstractUsing 15 parameters, we provide a systematic description of mammal proximal femoral morphology. We established two types of proximal femoral morphology, termed coxa recta and coxa rotunda, characterized by low versus high concavity of the head–neck junction. Concavity is a measure of the sphericity of the femoral head as it meets the femoral neck that can be quantified by angular measurements. We asked whether the parameter of concavity corresponds with the classification of mammal proximal femoral morphology based on coalesced versus separate ossification patterns and locomotor patterns. Statistical analysis demonstrated a distinction between coxa recta and coxa rotunda with significant differences between the two groups in all but 3 of the 15 parameters examined. We found the most discriminating measurement between mammal hips to be the concavity of the posterior head–neck junction (beta angle). Coxa recta (small concavity) and coxa rotunda (large concavity) relate to the ossification pattern seen in proximal femoral development, and species‐specific patterns of locomotion. We interpret the two hip types to reflect optimization for strength (recta) versus mobility (rotunda). Conceptually, both hip types can be recognized in humans, where coxa recta can be related to the development of osteoarthritis. Anat Rec, 2013. © 2012 Wiley Periodicals, Inc.
Continuous purification of antibodies from cell culture supernatant with aqueous two‐phase systems: From concept to process
Authors: Rosa Paula A. J. , Azevedo Ana M. , Sommerfeld S. , Mutter Martina , Bäcker Werner , Aires‐Barros M. Raquel 
Published: December 2012

AbstractAn aqueous two‐phase extraction (ATPE) process based on a PEG/phosphate system was developed for the capture of human immunoglobulin G and successfully applied to a Chinese hamster ovary and a PER.C6® cell supernatant. A continuous ATPE process incorporating three different steps (extraction, back‐extraction, and washing) was set up and validated in a pump mixer‐settler battery. Most of the higher molecular weight cell supernatant impurities were removed during the extraction step, while most of the lower molecular weight impurities were removed during the subsequent steps. A global recovery yield of 80% and a final protein purity of more than 99% were obtained for the IgG purification from a CHO cell supernatant, representing a 155‐fold reduction in the protein/IgG ratio. For the purification of IgG from a PER.C6® cell supernatant, a global recovery yield of 100%, and a host cell protein purity were attained, representing a 22‐fold reduction in the host cell protein/IgG ratio. These results, thus, open promising perspectives for the application of the developed ATPE process as a platform for the capture of antibodies. In fact, this new process has shown the ability to successfully recover and purify different antibodies from distinct cell culture supernatants. This technology can also overcome some of the limitations encountered using the typical chromatographic processes, besides inherent advantages of scalability, process integration, capability of continuous operation, and economic feasibility.
PM10 Source Apportionment in Ahvaz, Iran, Using Positive Matrix Factorization
Authors: Sowlat Mohammad Hossein , Naddafi Kazem , Yunesian Masud , Jackson Peter L. , Lotfi Saeedeh , Shahsavani Abbas 
Published: December 2012

AbstractSource apportionment of particulate matter <10 µm in diameter (PM10), having considerable impacts on human health and the environment, is of high priority in air quality management. The present study, therefore, aimed at identifying the potential sources of PM10 in an arid area of Ahvaz located in southwest of Iran. For this purpose, we collected 24‐h PM10 samples by a high volume air sampler. The samples were then analyzed for their elemental (Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, Pb, Se, Si, Sn, Sr, Li, Ti, V, Zn, Mo, and Sb) and ionic (NH, Cl−, NO, and SO) components using inductively coupled plasma optical emission spectrometry and ion chromatography instruments, respectively. Eight factors were identified by positive matrix factorization: crustal dust (41.5%), road dust (5.5%), motor vehicles (11.5%), marine aerosol (8.0%), secondary aerosol (9.5%), metallurgical plants (6.0%), petrochemical industries and fossil fuel combustion (13.0%), and vegetative burning (5.0%). Result of this study suggested that the natural sources contribute most to PM10 particles in the area, followed closely by the anthropogenic sources.
High‐performance execution of service compositions: a multicore‐aware engine design
Authors: Peternier Achille , Pautasso Cesare , Binder Walter , Bonetta Daniele 
Published: December 2012

SUMMARYAlthough modern computer hardware offers an increasing number of processing elements organized in nonuniform memory access (NUMA) architectures, prevailing middleware engines for executing business processes, workflows, and Web service compositions have not been optimized for properly exploiting the abundant processing resources of such machines. Amongst others, factors limiting performance are inefficient thread scheduling by the operating system, which can result in suboptimal use of system memory and CPU caches, and sequential code sections that cannot take advantage of multiple available cores.In this article, we study the performance of the JOpera process execution engine on recent multicore machines. We first evaluate its performance without any dedicated optimization for multicore hardware, showing that additional cores do not significantly improve performance, although the engine has a multithreaded design. Therefore, we apply optimizations on the basis of replication together with an improved, hardware‐aware usage of the underlying resources such as NUMA nodes and CPU caches. Thanks to our optimizations, we achieve speedups from a factor of 2 up to a factor of 20 (depending on the target machine) when compared with a baseline execution ‘as is’. Copyright © 2012 John Wiley & Sons, Ltd.
Finding exemplars in dense data with affinity propagation on clusters of GPUs
Authors: Kurdziel Marcin , Boryczko Krzysztof 
Published: December 2012

SUMMARYThis work presents an efficient implementation of affinity propagation (AP) on clusters of graphical processing units (GPUs). AP is a state‐of‐the‐art method for finding exemplars in data sets described by similarity matrices. It is typically employed in crisp clustering applications. However, when finding exemplars in an n‐pattern data set with dense, non‐metric similarities, AP performs iterative processing of three n × n floating point matrices. One of them stores the similarities, and the other two store the values that will ultimately pinpoint the exemplars. For large similarity matrices, AP is therefore computationally expensive. Although matrix operations of AP are well suited for GPUs, its memory footprint limits the size of tasks that can be solved on one unit. We present, however, a decomposition scheme for AP that distributes the calculations over multiple GPUs, with low communication‐to‐computation ratio. Because of this favorable communication pattern, our implementation finds exemplars in large, dense similarity data efficiently, even when GPUs are connected by a slow network. Furthermore, by combining global device memory of multiple GPUs, it can solve problems that would not fit in a single unit. Copyright © 2012 John Wiley & Sons, Ltd.
Dendritic Polyoxometalate Hybrids: Efficient and Recoverable Catalysts for Oxidation Reactions
Authors: Nlate Sylvain , Jahier Claire 
Published: December 2012

AbstractThe purpose of this microreview is to highlight developments in dendritic polyoxometalate (DENDRI‐POM) hybrid materials and their catalytic application in oxidation reactions. To the best of our knowledge, there are no reviews dealing with the design and synthesis of DENDRI‐POM hybrids and their use as catalysts. Thus, this article will mainly focus on research carried out in our group, including a brief summary of the work done by others in the field. The context includes the design and synthetic strategies for DENDRI‐POM materials, including chiral counterparts, and the use of DENDRI‐POM materials as recoverable catalysts. We show that the properties of POMs, such as, their solubility, stability, and catalytic efficiency and selectivity, including enantioselectivity, can be tuned by varying the structure of the dendritic part in the DENDRI‐POM framework.
Poly(trimethylene terephthalate)/magnesium hydroxide composites with on‐demand thickening at high temperatures
Authors: Messmore Benjamin W. , Zudans Andrew W. , Pottiger Michael T. , Berl Anna G. 
Published: December 2012

AbstractMagnesium hydroxide, when melt extruded with poly(trimethylene terephthalate) (PTT) at low concentrations (1–3 wt.%), can be melt processed during extrusion and injection molding. When the polymer is heated in the melt to 295°C, the viscosity of the composite behaves similarly to control samples and the viscosity decreases as a function of temperature. When the temperature of the composite is raised above 295°C (above the normal processing conditions for PTT), a significant change in the melt rheology of the composite is observed relative to unfilled compositions. This change in melt rheology coincides with the decomposition temperature of magnesium hydroxide and formation of magnesium oxide, a common thickening agent employed in unsaturated polyester resins. Lower processing temperature polyesters, including PTT, enable processing of the polymer in the presence of magnesium hydroxide under normal conditions. The viscosity modifier ‘turns on’ when the composite sees elevated temperature where magnesium oxide is known to form. The magnesium oxide is hypothesized to interact with PTT carboxyl end groups, providing the observed increase in viscosity. The rheological response observed in the composites is dependent on the concentration of magnesium hydroxide. During burning, the viscosity modifier results in a non‐dripping formulation of PTT. Copyright © 2012 John Wiley & Sons, Ltd.
Molecular mechanism of WW‐domain binding protein‐2 coactivation function in estrogen receptor signaling
Authors: Buffa Laura , Saeed Ali M. , Nawaz Zafar 
Published: December 2012

AbstractThe link between breast cancer and estrogen receptor (ER) is well established. The ER is a hormone‐inducible transcription factor that, upon binding to its ligand, regulates the expression of a variety of genes mainly involved in cell proliferation and differentiation. Coactivators are proteins recruited by the hormone‐activated receptor, which allow or enhance the ER transactivation functions by acting as chromatin remodeling enzymes or adaptors between ER and the transcriptional machinery. Our laboratory has previously identified the WW‐domain binding protein‐2 (WBP‐2) as a bona fide coactivator of ER. However, the molecular mechanism underlying WBP‐2 coactivation function was not clear yet. In this study, we explore and identify the mechanism by which WBP‐2 acts as coactivator of ER. Our data show that WBP‐2 is involved in the regulation of ER target genes, and its expression is required for the proper expression of some ER target genes. To clarify the molecular mechanism by which WBP‐2 regulates ER function, we performed chromatin immunoprecipitation assays. We demonstrate here that WBP‐2 binds to the ER target gene promoter pS2 promoter and is required for the binding of the phosphorylated form of RNA polymerase II (associated with active transcription/elongation) to the same promoter. Furthermore, we also show that WBP‐2 is essential for the recruitment of the histone acetyl transferase p300, an important chromatin modifier enzyme and for histone acetylation at the same target region. Collectively, our data indicate that WBP‐2 enhances ER transactivation function at certain genes by facilitating the recruitment and/or the stabilization of a histone modifier enzyme that favors a relaxed chromatin structure, permissive of transcription. © 2012 IUBMB Life,
65(1):76–84, 2013
Synthesis and Characterization of pH‐Sensitive Positive‐charge Silica Nanoparticles for Oral Anionic Drug Delivery
Authors: Mahkam Mehrdad , Pakravan Asrin 
Published: December 2012

AbstractThe objective of this study is to utilize the pH sensitivity of modified mesoporous silica nanoparticles (MSN) for oral drug delivery. In the first time, a pH‐sensitive ionic liquid was synthesized through the quaternization of 3‐aminopropyltrimethoxysilane (3‐ATMS) with sodium monochloroacetate (SMCA). Then, silica nanoparticle was modified by this pH‐sensitive ionic liquid and converted to a pH‐sensitive positive‐charge silica nanoparticle (PCSN). The nanoparticle was characterized by FTIR and SEM. Naproxen as anionic drug molecules was entrapped in this pH‐sensitive positive‐charge silica nanoparticles (PCSN) and the in vitro release profiles were established separately in both (SGF, pH 1) and (SIF, pH 7.4).
Effects of paternal folate deficiency on the expression of insulin‐like growth factor‐2 and global DNA methylation in the fetal brain
Authors: Kim Hye Won , Kim Ki Nam , Choi Yun Jung , Chang Namsoo 
Published: December 2012

ScopeWe examined the effect of paternal folate deficiency on the folate content, the percentage of 5‐methycytosine (percentage of 5‐mC) in the total DNA, and the protein expression of insulin‐like growth factor‐2 (IGF‐2) in the fetal whole brain.Methods and resultsRats were mated after males were fed a folic acid deficient (PD) or folic acid supplemented (PS) diet for 4 weeks, and fetuses were killed on day 20 of gestation. The folate content in the fetal liver was significantly lower in the PD group than in the PS group, whereas it did not differ in the fetal whole brain. The percentage of 5‐mC and the protein expression of IGF‐2 in the fetal whole brain were both lower in the PD group than in the PS group. There were positive correlations between paternal liver and testis folate content and the percentage of 5‐mC and IGF‐2 expression in the fetal whole brain.ConclusionOur results on the folate content, the percentage of 5‐mC, and IGF‐2 expression in the fetal whole brain show that paternal folate deficiency at mating can influence fetal brain DNA methylation and IGF‐2 expression despite an adequate maternal folate status during the gestational period.
Crystallization and morphology studies of biodegradable poly(ε‐caprolactone)/silica nanocomposites
Authors: Li Yi , Han Changyu , Bian Junjia , Zhang Xin , Han Lijing , Dong Lisong 
Published: December 2012

AbstractBiodegradable poly(ε‐caprolactone) (PCL)/silica nanocomposites at various silica loadings were prepared via direct melt compounding method in this work. Scanning electron microscopy observation indicated that when the silica content was < 3 wt%, the nanoparticles dispersed evenly in the PCL matrix and exhibited only aggregates with particle size of less than 100 nm. The results of nonisothermal melt crystallization showed that the crystallization peak temperature was higher in the nanocomposites than in neat PCL; moreover, the overall crystallization rate was faster in the nanocomposites than in neat PCL during isothermal melt crystallization. Both nonisothermal and isothermal melt crystallization studies suggested that the crystallization of PCL was enhanced by the presence of silica and influenced by the silica loading. The effect of silica on the crystallization behavior was twofold: the presence of silica may provide heterogeneous nucleation sites for the PCL crystallization while the aggregates of silica may restrict crystal growth of PCL. However, the crystal structure of PCL remained almost unchanged despite the presence of silica in the nanocomposites. POLYM. COMPOS., 2013. © 2012 Society of Plastics Engineers
Double‐hydrophobic siloxane diblock copolymers: Synthesis, micellization behavior, and application as a stabilizer for silver nanoparticles
Authors: Zhou Hong‐Ming , Cheng Hua , Luo Zheng‐Hong 
Published: December 2012

AbstractThe double‐hydrophobic well‐defined polydimethylsiloxane‐block‐poly(methyl methacrylate) (PDMS‐b‐PMMA) diblock copolymers were synthesized via atom transfer radical polymerization (ATRP). Their chemical compositions and the structure were investigated. The micellization behavior of the double‐hydrophobic diblock copolymers with equal block length was thoroughly studied. The results showed that their self‐assembly behavior was analogous to the star‐like micelles. Furthermore, the effect of temperature on the aggregates was investigated to verify that the resulting copolymer (PDMS‐b‐PMMA) was to some extent temperature sensitive. Till date, there have been few reports on the utilization of nonamphiphilic block copolymers to synthesize and confine metal nanoparticles in aggregates. In this study, we explored the role of double‐hydrophobic block copolymers as a mediator for organically dispersible silver nanoparticles (AgNPs) and it offered to be an effective stabilizer for preparing AgNPs. Besides, AgNPs generated in organic solvent is an important addition to the hitherto predominantly water‐based processes for producing nanoparticles inside the polymer surfactant. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
The influence of bending on the performance of flexible carbon black/polymer composite gas sensors
Authors: Kinkeldei Thomas , Zysset Christoph , Münzenrieder Niko , Tröster Gerhard 
Published: December 2012

AbstractThe performance of electronics on flexible substrates suffers under substrate bending leading to reduced device performance. In this article, we highlighted the influence of bending strain on a conductive polymer composite gas sensor and developed a model to investigate the influence of strain. We evaluated the strain influence on the resistance of a gas sensor with respect to sensitivity, filler content, cyclic loading, and electrode orientation. The sensitivity of gas sensors increased with decreasing tensile bending radii. The influence of strain was dominant for gas sensors with less carbon black concentration. Cyclic bending tests showed a decrease of sensor resistance versus time and a plastic deformation. A sensor geometry orientations effect to reduce the sensitivity to bending strain was achieved by aligning the electrode fingers parallel to the strain. A model was successfully implemented to simulate strain influences inside the polymer incorporating the Poisson ratio. We suggest a concept to achieve a strain insensitive gas sensor by creating an orientation between single particles inside the composite. Implementing this results into existing gas sensors will improve the measurement quality and reliability of sensors on flexible substrates. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013
The effect of mixing methods on the dispersion of carbon nanotubes during the solvent‐free processing of multiwalled carbon nanotube/epoxy composites
Authors: Gupta Murari L. , Sydlik Stefanie A. , Schnorr Jan M. , Woo Dong Jin , Osswald Sebastian , Swager Timothy M. , Raghavan Dharmaraj 
Published: December 2012

AbstractSeveral solvent‐free processing methods to disperse multiwalled carbon nanotubes (MWCNTs) in bisphenol F‐based epoxy resin were investigated, including the use of a microfluidizer (MF), planetary shear mixer (PSM), ultrasonication (US) and combinations. The processed mixture was cured with diethyl toluene diamine. Three complimentary techniques were used to characterize the dispersion of the MWCNTs in cured composite samples: optical microscopy, micro Raman spectroscopy, and scanning electron microscopy (SEM). For sample MF + PSM, optical micrographs and Raman images showed reduced agglomeration and a homogeneous distribution of MWCNTs in the epoxy matrix. SEM analysis of fractured specimen after tensile testing revealed breakage of nanotubes along the fracture surface of the composite. A comparison of the MWCNT dispersion in the epoxy samples processed using different methods showed that a combination of MF and PSM processing yields a more homogeneous sample than the PSM or US + PSM processed samples. Mechanical testing of the composites showed about 15% improvement in the tensile strength of samples processed by the MF + PSM method over other methods. Thermogravimetric analysis (TGA) results showed a small decrease in the onset degradation temperature for poorly dispersed samples produced by PSM compared with the well‐mixed samples (MF + PSM). These results strongly suggest that the MF + PSM processing method yield better‐dispersed and stronger MWCNT/epoxy composites. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013