bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rheological behaviors of glass bead‐ and wollastonite‐filled polypropylene composites modified with thermoplastic elastomers
Authors: Balkan Onur , Ezdeşir Ayhan 
Published: May 2012

AbstractSteady‐ and oscillatory‐shear rheological behaviors of polypropylene/glass bead (PP/GB) and PP/wollastonite (PP/W) melts modified with thermoplastic elastomers, poly(styrene‐b‐ethylene‐co‐butylene‐b‐styrene) copolymer (SEBS) and the corresponding block copolymer grafted with maleic anhydride (SEBS‐g‐MA), were examined by means of a parallel‐plate rheometer. With adding the elastomers (SEBS and SEBS‐g‐MA) and fillers (spherical GB and acicular W) to PP, viscosity especially at low shear rates and shear‐thinning flow behavior at high shear rates were pronounced as evidenced quantitatively by Carreau–Yasuda (CY) parameters, but Cox–Merz analogy became weakened. Besides, melt‐elasticity in terminal region and relaxation time (tc) in crossing point increased, indicating an enhancement in quasi‐solid behavior of molten PP. Comparing with the elastomers, rheological behaviors of molten PP were more influenced with adding the rigid fillers, especially with W due to distinct acicular shape of W particles. SEBS‐g‐MA elastomer more affected rheological behaviors of the ternary composites than SEBS elastomer, implying that SEBS elastomer and the filler particles behaved individually (i.e., development of separate microstructure) in (PP/GB)/SEBS and (PP/W)/SEBS ternary composites, but core‐shell microstructure developed with strong interfacial adhesion by adding SEBS‐g‐MA elastomer, and the filler particles encapsulated with the thick SEBS‐g‐MA elastomer interlayer (i.e., core‐shell particles) acted like neither big elastomer particles nor like individual rigid particles in melt‐state. Moreover, effects of SEBS‐g‐MA elastomer reached a maximum on rheological behaviors of (PP/W)/SEBS‐g‐MA ternary composite, indicating a synergy between core‐shell microstructure and acicular W particles. Correlations between oscillatory‐shear flow properties and microstructures of the blends and composites were evaluated using Cole–Cole (CC), Han–Chuang (HC), and van Gurp–Palmen (vGP) plots. COMPOS., 2012. © 2012 Society of Plastics
Structure and properties of peroxide dynamically vulcanized polypropylene/ethylene–propylene–diene/zinc dimethacrylate composites
Authors: Chen Yukun , Xu Chuanhui , Cao Liming , Wang Yanpeng 
Published: May 2012

AbstractPeroxide dynamically vulcanized thermoplastic olefin (TPO) based on polypropylene (PP)/ethylene–propylene–diene (EPDM) loaded with zinc dimethacrylate (ZDMA) was prepared. The addition of ZDMA improved the complex viscosity of the resulting materials in the melt state significantly, as determined from oscillatory rheology analyses. Dynamic mechanical analysis (DMA) and transmission electron microscopy (TEM) examinations were performed to evaluate the structure of the PP/EPDM/ZDMA composite. Atomic force microscope (AFM) and scanning electron microscopy (SEM) were used to study the morphology. The degree of crystallinity was evaluated using X‐ray diffraction method (XRD). The results revealed that incorporation of ZDMA resulted in a size reduction of the rubber droplets and improved the compatibility between rubber and PP phases. The nanoparticles of the polymerized ZDMA (PZDMA) served as an effective nucleating agent for the crystallization of PP. The rheological properties and mechanical properties were improved by ZDMA. Particularly, the izod impact strength of the PP/EPDM/ZDMA (80/20/6, w/w) composite is nearly 2 times higher than the PP/EPDM (80/20, w/w) and 12 times higher than the PP; besides, the elongation at break of the PP/EPDM/ZDMA (80/20/6, w/w) is 3 times higher than that of the PP/EPDM (80/20, w/w) and 6 times higher than the PP. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Preparation of chitosan‐nanohydroxyapatite composite scaffolds by a supercritical CO2 assisted process
Authors: Karakeçili Ayşe , Arıkan Ayşegül 
Published: May 2012

AbstractIn this study, chitosan‐nanohydroxyapatite composite scaffolds were prepared by a supercritical fluid assisted process. For this purpose, different amounts of nanohydroxyapatite particles, that is, 0.25, 0.50, and 1.00 wt% were added to chitosan (deacetylation degree: DD 75–85%) solution (2%, w/v, in acetic acid). The gels were then frozen at −20°C, treated in acetone and dried in a supercritical fluid extractor under a constant CO2 flow of 15 g/min at 35°C and 200 bar for 5 h to obtain porous scaffolds. Scanning electron microscope views showed that the drying of gels under supercritical CO2 lead to the formation of microporous scaffolds with a pore size distribution of 30–150 μm. Addition of nanohydroxyapatite particles did not significantly affect the pore size distribution. Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy and X‐Ray diffraction analyses supported the successful incorporation of nanohydroxyapatite particles in the scaffold. An increase in water uptake and mechanical strength were observed in composite scaffolds. The results obtained from this study indicated that chitosan‐nanohydroxyapatite scaffolds prepared by using supercritical CO2 shall be considered as a potential candidate for bone tissue engineering applications. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Life cycle assessment of high‐concentration photovoltaic systems
Authors: Fthenakis Vasilis M. , Kim Hyung Chul 
Published: May 2012

ABSTRACTThe environmental profiles of photovoltaic (PV) systems are becoming better as materials are used more efficiently in their production, and overall system performance improves. Our analysis details the material and energy inventories in the life cycle of high‐concentration PV systems, and, based on measured field‐performances, evaluates their energy payback times, life cycle greenhouse gas emissions, and usage of land and water. Although operating high‐concentration PV systems require considerable maintenance, their life cycle environmental burden is much lower than that of the flat‐plate c‐Si systems operating in the same high‐insolation regions. The estimated energy payback times of the Amonix 7700 PV system in operation at Phoenix, AZ, is only 0.9 year, and its estimated greenhouse gas emissions are 27 g CO2‐eq./kWh over 30 years, or approximately 16 g CO2‐eq./kWh over 50 years. Copyright © 2012 John Wiley & Sons, Ltd.
Plasma Directed Organization of Nanodots on Polymers: Effects of Polymer Type and Etching Time on Morphology and Order
Authors: Kontziampasis Dimitrios , Constantoudis Vassilios , Gogolides Evangelos 
Published: May 2012

AbstractOxygen plasma etching of poly(methyl methacrylate) (PMMA), poly(ethylene terephthalate) (PET), and polystyrene (PS) leads to the formation of organized nanodots on the surfaces of the polymers. In this paper, we describe the metrological characterization of these nanodots and compare their morphology as a function of the polymer type. We study the evolution of the surface morphology with etching time and observe a transition point where dual scale roughness develops, order is lost, and sudden increase in the surface roughness is observed. Possible mechanisms are discussed. magnified image
Cost Effective Deposition System for Nitrogen Incorporated Diamond‐like Carbon Coatings
Authors: Kumar Sushil , Dwivedi Neeraj , Kumar Dalai Manas 
Published: May 2012

AbstractNitrogen incorporated diamond‐like carbon (N‐DLC) thin films were grown, at high base pressure of 5 × 10−3 Torr, under varied nitrogen gas pressure (NGP) (variation from 55 to 85 mTorr) and varied negative self‐bias (NSB) (variation from 35 to 190 V), using primary pump (rotary pump) processed radio frequency‐plasma enhanced chemical vapour deposition technique. These films then studied for their structural compositional and nanomechanical properties. Time of flight‐secondary ion mass spectroscopy was used to confirm the presence of nitrogen and to investigate the depth profile of these N‐DLC films, whereas energy dispersive X‐ray analysis measurement was carried to analyze the atomic concentration of constituents of film. Micro‐Raman analysis reveals change in D and G peak positions and ID/IG ratio with the change in NSB as well as NGP. It is worth noting that N‐DLC film grown at NGP and NSB of 55 mTorr and 100 V, respectively, exhibited very high hardness as 40.3 GPa. Hence, due to better nanomechanical properties by simpler, high deposition rate and cost effective process, which yielded very high throughput may leads these N‐DLC films to their wide industrial applications such as hard and protective coating on cutting tools, automobile parts, bio‐implants or wear resistant coating on magnetic hard disk. magnified image
High quality p‐type chemical vapor deposited {111}‐oriented diamonds: Growth and fabrication of related electrical devices
Authors: Lazea Andrada , Garino Yiuri , Teraji Tokuyuki , Koizumi Satoshi 
Published: May 2012

AbstractIn this paper the quality of boron‐doped diamond films grown by microwave (MW) plasma activated chemical vapor deposition on high pressure high temperature synthetic type Ib {111}‐oriented diamond substrates is estimated from the correlations between low‐temperature cathodoluminescence analyses and Hall measurements. The layers attributes, obtained in the low methane concentration regime (0.05% [CH4]/[H2] ratio) and using low plasma powers (450–500 W), are completed by impurities incorporation investigations (secondary ion mass spectroscopy). Hall mobility values exceeding 550 cm2 V−1 s−1 at room temperature and characteristic excitonic luminescence peaks were obtained, indicating towards the high crystalline quality of our {111}‐oriented diamond films. Based on these B‐doped samples, Schottky junctions were fabricated and analyzed, presenting the highest rectification ratio when compared with similar devices.
On analytical properties of the diamagnetic permeability in the presence of the spatial dispersion
Authors: Pitaevskii L. P. 
Published: May 2012

AbstractIt is well known that the usual assumptions about analytical properties of the magnetic permeability μ result in a contradiction in the case of a diamagnetic. It occurs, that the permeability, as a function of the complex frequency ω, decreases monotonically along the imaginary half‐axis in the upper half of the ω‐plane and, consequently, can not reach the limiting value μ = 1 at |ω| → ∞ as it must do. It is discussed how the presence of the spatial dispersion may solve this paradox. © 2012 Wiley Periodicals, Inc.
Non‐convex model for sensor network localization based on connectivity
Authors: Qiao Dapeng , Pang Grantham K.H. 
Published: May 2012

ABSTRACTIn this paper, a new model utilizing all the information derived from connectivity‐based sensor network localization is introduced. The connectivity information between any pair of nodes is modeled as convex and non‐convex constraints. The localization problem is solved by searching for a solution that would satisfy all the constraints established in the problem. A two‐objective evolutionary algorithm called Pareto Archived Evolution Strategy (PAES) is used to solve the localization problem. The solution can reach the most suitable configuration of the unknown nodes because the information on both convex and non‐convex constraints related to connectivity has been utilized. From simulation results, a relationship between the communication range and accuracy is obtained. Furthermore, a two‐level range connectivity‐based sensor network localization method is proposed to enrich the connectivity information. The two‐level range/indication of connectivity between each pair of nodes would indicate three levels of connectivity: strong, weak, or nil. A comparison on accuracy between the one‐level and two‐level ranges of connectivity is carried out by simulation using six different topological networks all containing 100 nodes. Simulation results have shown that better solution can be obtained by using two‐level range connectivity compared with the usual one‐level range connectivity‐based localization. Copyright © 2012 John Wiley & Sons, Ltd.
A systematic approach to exosome‐based translational nanomedicine
Authors: Hood Joshua L. , Wickline Samuel A. 
Published: May 2012

AbstractExosomes are a type of cell‐derived extracellular nanovesicle. They relay information between cells. Some known exosome functions include immune modulation, promotion of angiogenesis, and tumor metastasis. To date, clinical use of exosomes has focused predominantly on evaluating their efficacy as cancer vaccines or diagnostically as biomarker containers. However, few investigations have explored their potential to serve as a platform for the development of semi‐synthetic nanovesicles. Given their nanoscale size, potential to express targeting ligands in native conformations and deformable structure, exosomes offer a logical biological vesicle platform for adapting and producing semi‐synthetic vesicles with excellent potential for nanomedicine applications. However, there are obstacles associated with realizing this potential that must be addressed. Thus, a systematic approach to isolating, modifying, and testing exosomes is presented to facilitate the introduction of exosome‐based translational nanomedicine. WIREs Nanomed Nanobiotechnol 2012, 4:458–467. doi: 10.1002/wnan.1174This article is categorized under:

Diagnostic Tools > Diagnostic Nanodevices
Nanotechnology Approaches to Biology > Nanoscale Systems in Biology
Effects of Second Language Usage on Genetic Counseling Training and Supervision
Authors: Vanneste Rachel , Chiu Sui Mei , Russell Laura , Fitzpatrick Jennifer 
Published: May 2012

AbstractWe conducted an exploratory study of the experiences of genetic counselors who have either trained or supervised in a second language to assess the relevance of this issue to genetic counseling training and supervision. Two hundred‐thirty NSGC members, CAGC members and genetic counseling students completed the online questionnaire. Many of the respondents reported that training and supervision differed when another language was involved. Supervisors reported difficulty in assessing students’ counseling skills and discomfort with an incomplete understanding of session content. Students described a greater focus on vocabulary at the expense of psychosocial dimensions. Despite this, most felt that using another language enhanced their training experience. As such, training programs might consider increasing support to these learners and supervisors by explicitly acknowledging the challenges they face, providing students with language tools to aid in their acquisition of basic skills and providing supervisors with new methods for assessing student counseling skills when using other languages.
Chapter 9: Options for Summarizing Medical Test Performance in the Absence of a “Gold Standard”
Authors: Trikalinos Thomas A. , Balion Cynthia M. 
Published: May 2012

Abstract
The classical paradigm for evaluating test performance compares the results of an index test with a reference test. When the reference test does not mirror the “truth” adequately well (e.g. is an “imperfect” reference standard), the typical (“naïve”) estimates of sensitivity and specificity are biased. One has at least four options when performing a systematic review of test performance when the reference standard is “imperfect”: (a) to forgo the classical paradigm and assess the index test’s ability to predict patient relevant outcomes instead of test accuracy (i.e., treat the index test as a predictive instrument); (b) to assess whether the results of the two tests (index and reference) agree or disagree (i.e., treat them as two alternative measurement methods); (c) to calculate “naïve” estimates of the index test’s sensitivity and specificity from each study included in the review and discuss in which direction they are biased; (d) mathematically adjust the “naïve” estimates of sensitivity and specificity of the index test to account for the imperfect reference standard. We discuss these options and illustrate some of them through examples.
Cancer cachexia is associated with a decrease in skeletal muscle mitochondrial oxidative capacities without alteration of ATP production efficiency
Authors: Julienne Cloé M. , Dumas Jean‐François , Goupille Caroline , Pinault Michelle , Berri Cécile , Collin Anne , Tesseraud Sophie , Couet Charles , Servais Stephane 
Published: May 2012

BackgroundCancer cachexia is a complex syndrome related to a negative energy balance resulting in muscle wasting. Implication of muscle mitochondrial bioenergetics alterations during cancer cachexia was suggested. Therefore, the aim of this study was to explore the efficiency of oxidative phosphorylation in skeletal muscle mitochondria in a preclinical model of cancer cachexia.MethodsBerlin–Druckrey IX rats with peritoneal carcinosis (PC) were used as a model of cancer cachexia with healthy pair‐fed rats (PF) as control. Hindlimb muscle morphology and fibre type composition were analysed in parallel with ubiquitin ligases and UCP gene expression. Oxidative phosphorylation was investigated in isolated muscle mitochondria by measuring oxygen consumption and ATP synthesis rate.ResultsPC rats underwent significant muscle wasting affecting fast glycolytic muscles due to a reduction in fibre cross‐sectional area. MuRF1 and MAFbx gene expression were significantly increased (9‐ and 3.5‐fold, respectively) in the muscle of PC compared to PF rats. Oxygen consumption in non‐phosphorylating state and the ATP/O were similar in both groups. Muscle UCP2 gene was overexpressed in PC rats. State III and the uncoupled state were significantly lower in muscle mitochondria from PC rats with a parallel reduction in complex IV activity (−30 %).ConclusionThis study demonstrated that there was neither alteration in ATP synthesis efficiency nor mitochondrial uncoupling in skeletal muscle of cachectic rats despite UCP2 gene overexpression. Muscle mitochondrial oxidative capacities were reduced due to a decrease in complex IV activity. This mitochondrial bioenergetics alteration could participate to insulin resistance, lipid droplet accumulation and lactate production.
Effect of colon cancer and surgical resection on skeletal muscle mitochondrial enzyme activity in colon cancer patients: a pilot study
Authors: Phillips Bethan E. , Smith Kenneth , Liptrot Sarah , Atherton Philip J. , Varadhan Krishna , Rennie Michael J. , Larvin Mike , Lund Jonathan N. , Williams John P. 
Published: May 2012

BackgroundColon cancer (CC) patients commonly suffer declines in muscle mass and aerobic function. We hypothesised that CC would be associated with reduced muscle mass and mitochondrial enzyme activity and that curative resection would exacerbate these changes.MethodsWe followed age‐matched healthy controls and CC patients without distant metastasis on radiological imaging before and 6 weeks after hemi‐colectomy surgery. Body composition was analysed using dual energy X‐ray absorptiometry. Mitochondrial enzyme activity and protein concentrations were analysed in vastus lateralis muscle biopsies.ResultsIn pre‐surgery, there were no differences in lean mass between CC patients and age‐matched controls (46.1 + 32.5 vs. 46.1 + 37.3 kg). Post‐resection lean mass was reduced in CC patients (43.8 + 30.3 kg, P < 0.01). When comparing markers of mitochondrial function, the following were observed: pyruvate dehydrogenase (PDH) activity was lower in CC patients pre‐surgery (P < 0.001) but normalized post‐resection and cytochrome c oxidase and pyruvate dehydrogenase E2 subunit protein expression were lower in CC patients pre‐surgery and not restored to control values post‐resection (P < 0.001). Nuclear factor kappa‐B, an inflammatory marker, was higher in CC patients pre‐surgery compared to controls (P < 0.01), returning to control levels post‐resection.ConclusionMuscle mass was affected by surgery rather than cancer per se. PDH activity was however lower in cancer patients, suggesting that muscle mass and mitochondrial enzyme activity are not inextricably linked. This reduction in mitochondrial enzyme activity may well contribute to the significant risks of major surgery to which CC patients are exposed.
Comparison of PET/CT with other imaging modalities in women with genital tuberculosis
Authors: Sharma Jai B. , Karmakar Debjyoti , Kumar Rakesh , Shamim Shamim A. , Kumar Sunesh , Singh Neeta , Roy Kallol K. , Reddy Rama M. 
Published: May 2012

AbstractObjectiveTo compare findings with 2‐deoxy‐2‐(18F)fluoro‐D‐glucose positron emission tomography combined with computed tomography (18F‐FDG‐PET/CT) with findings obtained using ultrasound (US), magnetic resonance imaging (MRI), and CT in patients with proven tubercular tubo‐ovarian masses.MethodsSeventeen patients with proven tubercular tubo‐ovarian masses underwent 18F‐FDG‐PET/CT imaging and the findings were compared with US (for all patients), MRI (for 9 patients), CT (for 4 patients), and laparotomy or laparoscopic findings (for 14 patients).ResultsEleven patients (64.7%) had unilateral tubo‐ovarian masses, with activity in 6 masses (35.3%); 4 patients (23.5%) had bilateral tubo‐ovarian masses, with activity in all masses; and 2 patients (11.76%) had unilateral space‐occupying lesions, with activity in 1 lesion. The detection rates of tubo‐ovarian masses with 18F‐FDG‐PET/CT were similar to, but the characterization of adnexal masses was less than, those obtained with CT or MRI. Finally, 18F‐FDG‐PET/CT was equally accurate as laparoscopy or laparotomy in detecting the presence, laterality, and activity of tubo‐ovarian masses.ConclusionImaging with 18F‐FDG‐PET/CT is noninvasive and appears to be clinically useful for the diagnosis of tubercular tubo‐ovarian masses.
Mastodon herbivory in mid-latitude late-Pleistocene boreal forests of eastern North America
Authors: Teale Chelsea L. , Miller Norton G. 
Published: May 2012

AbstractSkeletal remains of the extinct American mastodon have often been found with deposits of short, decorticated twigs intermixed with plant fragments presumed to be gastrointestinal or fecal material. If such deposits are digesta, paleobotanical evidence may be used to analyze mastodon foraging strategy, with implications for assessing habitat selection, ecological roles, and response to environmental change. To identify components of mastodon diet in mid-latitude late-Pleistocene boreall forests of eastern North America, plant macrofossils and pollen from a molar socket (Hyde Park site, New York) were compared with dispersed deposits associated with skeletal remains (Hiscock and Chemung sites, New York). Similar macrofossil condition and twig morphology among samples, but difference from a modern boreal fen analog, confirmed the deposits were digesta. Comparison of twigs with material from other paleontological sites and modern elephants suggested dimensions generally indicative of digesta. Picea formed the bulk of each sample but Pinus may have been locally important. Wintertime browsing of Salix and Populus, and springtime consumption of Alnus, were indicated. Evidence for Cyperaceae, Gramineae, and Compositae was ambiguous. If conifers, broadleaf trees, shrubs, and herbs were necessary to fulfill dietary requirements, mastodons would have been nutritionally stressed by rapid late-Pleistocene decrease in vegetational diversity.