bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of external electric field on the microstructures and properties of carbon nanotubes/thermosets nanocomposites
Authors: Duan Jingkuan , Kim Chonung , Jiang Pingkai 
Published: February 2009

AbstractThe alignment of multiwalled carbon nanotubes (MWCNTs) and thermosetting resins in nanocomposites based on field‐aided micro‐tailoring (FAiMTa) technology was studied by means of scanning electric microscopy (SEM), Raman spectroscopy, and atomic force microscopy (AFM), and the effect of the different values of electric field intensity on the changes of the microstructures and properties of nanocomposites were presented. The experimental results implied that the electric field encouraged the molecular alignment of polymers and MWCNTs orientation within the polymeric matrices along the field direction during their curing stages. It was found that the extents of their orientation and alignment were closely dependent on the external electric field intensity by means of Raman spectroscopy and AFM measurements. The thermal and dielectric properties of nanocomposites were examined by thermogravimetric analysis (TGA) and dielectric analysis (DEA), respectively. The TGA and DEA measurements revealed substantial differences in the thermal and dielectric behaviors for the thermoelectrically processed nanocomposites. These differences could be ascribed to the microstructural changes of matrix at the molecular level and the alignment of nanofillers. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Dynamic and capillary rheology of LDPE‐EVA–based thermoplastic elastomer: Effect of silica nanofiller
Authors: Hui Shalmali , Chaki Tapan K. , Chattopadhyay Santanu 
Published: February 2009

AbstractThe effect of pristine silica nanoparticles on the dynamic and capillary rheology of a model LDPE‐EVA thermoplastic elastomeric system is explored in this paper. The pristine silica nanoparticles were melt‐blended with the LDPE‐EVA system at 1.5, 3, and 5 wt% loadings, respectively, by varying the sequence of addition. In one of the compositions, coupling agent bis‐[3‐(triethoxysilyl)propyl] tetrasulphide (Si‐69) was used to improve the interaction of hydrophilic silica particles with polymer matrix. Results obtained reveal that the viscoelastic behavior of such composites is influenced remarkably by loadings of silica, variation of sequence, and addition of Si‐69. Upon addition of coupling agent, G′ value increases especially at higher strain levels due to increased polymer‐filler interactions. All systems with various loading of nanosilica represent an increase in elastic response with increasing frequency. Both the unfilled and filled blends exhibit rheological behavior of non‐Newtonian fluids. But interestingly, the viscoelastic response varies markedly with the temperature. The dynamic and steady shear rheological properties register a good correlation in regard to the viscous vs. elastic response of such systems. Finally, the rheological behavior is correlated with morphology of the present system processed at various shear rates. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Environmental effects on glass fiber reinforced polypropylene thermoplastic composite laminate for structural applications
Authors: Robert Mathieu , Roy René , Benmokrane Brahim 
Published: February 2009

AbstractThis article presents the mechanical and microstructural characterization of glass fiber reinforced polypropylene thermoplastic composite laminates (PP/Glass) exposed to tap water, salt solution, and freeze/thaw cycles. PP/Glass specimens were immersed at 23, 50, and 70°C in tap water to simulate the relative humidity of the direct environment and in a salt solution of 3% NaCl to simulate the effect of de‐icing salt. The measured flexural strengths of the specimens before and after exposure were considered as a measure of the durability performance of the specimens and were used for long‐term properties prediction based on the Arrhenius theory. In addition, the durability of PP/Glass to freeze/thaw cycles was studied for as received specimens and specimens saturated with tap water. Scanning electron microscopy was also used to characterize the effect of aging on the PP/Glass specimens. The results showed that the durability of PP/Glass composite is related to the quality of their consolidation. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Analysis of fire calls to an industrial complex over a 12‐year period
Authors: Cadwallader L.C. 
Published: February 2009

AbstractThis article gives an analysis of fire calls from over a decade of operations at a process facility complex operated by the Idaho National Laboratory. These data include valid alarms, unwanted or false alarms, ambulance calls, and hazardous material cleanup calls. Of special interest are false alarms, which are not only a nuisance to facility productivity but also are detrimental to public and facility safety. Of the fire calls listed here, over half were from false alarms. The results given are compared with National Fire Protection Association data. The data presented can serve as exemplar data for future facilities and can be compared with other operating facilities' experiences. © 2009 American Institute of Chemical Engineers Process Saf Prog, 2009
Modeling longitudinal count data with dropouts
Authors: Alosh Mohamed 
Published: February 2009

AbstractThis paper explores the utility of different approaches for modeling longitudinal count data with dropouts arising from a clinical study for the treatment of actinic keratosis lesions on the face and balding scalp. A feature of these data is that as the disease for subjects on the active arm improves their data show larger dispersion compared with those on the vehicle, exhibiting an over‐dispersion relative to the Poisson distribution. After fitting the marginal (or population averaged) model using the generalized estimating equation (GEE), we note that inferences from such a model might be biased as dropouts are treatment related. Then, we consider using a weighted GEE (WGEE) where each subject's contribution to the analysis is weighted inversely by the subject's probability of dropout. Based on the model findings, we argue that the WGEE might not address the concerns about the impact of dropouts on the efficacy findings when dropouts are treatment related. As an alternative, we consider likelihood‐based inference where random effects are added to the model to allow for heterogeneity across subjects. Finally, we consider a transition model where, unlike the previous approaches that model the log‐link function of the mean response, we model the subject's actual lesion counts. This model is an extension of the Poisson autoregressive model of order 1, where the autoregressive parameter is taken to be a function of treatment as well as other covariates to induce different dispersions and correlations for the two treatment arms. We conclude with a discussion about model selection. Published in 2009 by John Wiley & Sons, Ltd.
Gloss phenomena and image analysis of atomic force microscopy in molecular and cell biology
Authors: Zhu Jie , Sabharwal Tanya , Guo Lianhong , Kalyanasundaram Aruna , Wang Guodong 
Published: February 2009

AbstractProper sample preparation, scan setup, data collection and image analysis are key factors in successful atomic force microscopy (AFM), which can avoid gloss phenomena effectively from unreasonable manipulations or instrumental defaults. Fresh cleaved mica and newly treated glass cover were checked first as the substrates for all of the sample preparation for AFM. Then, crystals contamination from buffer was studied separately or combined with several biologic samples, and the influence of scanner, scan mode and cantilever to data collection was also discussed intensively using molecular and cellular samples. At last, images treatment and analysis with off‐line software had been focused on standard and biologic samples, and artificial glosses were highly considered for their high probability. SCANNING 31: 49–58, 2009. © 2009 Wiley Periodicals, Inc.
Confocal scanning optical microscopy of a 3‐million‐year‐old Australopithecus afarensis femur
Authors: Bromage T. G. , Goldman H. M. , McFarlin S. C. , Perez Ochoa A. , Boyde A. 
Published: February 2009

AbstractPortable confocal scanning optical microscopy (PCSOM) has been specifically developed for the noncontact and nondestructive imaging of early human fossil hard tissues, which here we describe and apply to a 3‐million‐year‐old femur from the celebrated Ethiopian skeleton, “Lucy,” referred to Australopithecus afarensis. We examine two bone tissue parameters that demonstrate the potential of this technology. First, subsurface reflection images from intact bone reveal bone cell spaces, the osteocyte lacunae, whose density is demonstrated to scale negatively with body size, reflecting aspects of metabolism and organismal life history. Second, images of a naturally fractured cross section near to Lucy's femoral mid‐shaft, which match in sign those of transmitted circularly polarized light, reveal relative collagen fiber orientation patterns that are an important indicator of femoral biomechanical efficacy. Preliminary results indicate that Lucy was characterized by metabolic constraints typical for a primate her body size and that in her femur she was adapted to habitual bipedalism. Limitations imposed by the transport and invasive histology of unique or rare fossils motivated development of the PCSOM so that specimens may be examined wherever and whenever nondestructive imaging is required. SCANNING 31: 1–10, 2009. © 2009 Wiley Periodicals, Inc.
Effect of fabrication process parameters on the apex‐radius of STM tungsten nanotip
Authors: Tahmasebipour Gh. , Hojjat Y. , Ahmadi V. , Abdullah A. 
Published: February 2009

AbstractScanning tunneling microscope (STM) has found a wide application in nanoscience and nanotechnology. This microscope uses an ultra‐sharp metallic tip for image acquisition. Resolution of STM images depends largely on the radius of the tip apex; the smaller the radius the higher the resolution. In the present research, an experimental set‐up was designed and implemented for fabrication of STM tungsten nanotip using electrochemical‐etching method with the aim of optimization of nanotip fabrication process parameters by using Taguchi method. These parameters are electrolyte concentration, immersion length of the tungsten wire, inner diameter of the cathode tube, and the process voltage. It was found that the optimum level of the process parameters for gaining minimum radius of the nanotip apex is electrolyte concentration of 2 M/lit, wire immersion length of 4 mm, cathode tube inner diameter of 55 mm, and voltage of 3.5 V within the range of experiments. By setting the process parameters on the optimum level, the radius of the nanotip apex was decreased by five times in comparison to the mean value of the experimental results. The radius of the nanotip apex was improved down to about 10 nm under the optimum conditions. SCANNING 31: 65–74, 2009. © 2009 Wiley Periodicals, Inc.
Cerebral biometry in fetal magnetic resonance imaging: new reference data
Authors: Tilea B. , Alberti C. , Adamsbaum C. , Armoogum P. , Oury J. F. , Cabrol D. , Sebag G. , Kalifa G. , Garel C. 
Published: February 2009

AbstractObjectivesTo provide normal magnetic resonance imaging (MRI) reference biometric data of the fetal brain, to evaluate reproducibility and gender effect, to compare the two cerebral hemispheres and to compare MRI with ultrasonographic biometry, in a large cohort.MethodsNormal cerebral fetal MRI examinations were collected prospectively and several parameters were measured: the supratentorial space (bone and cerebral fronto‐occipital and biparietal (BPD) diameters), the length of the corpus callosum (LCC), the surface area, height and anteroposterior diameter of the vermis, the transverse cerebellar diameter (TCD) and the anteroposterior diameter of the pons. We evaluated the interobserver reproducibility of measurements and the possible gender effect on measurements of bone BPD, TCD and LCC. We compared right and left hemispheres, right and left atria and ultrasound and MRI measurements.ResultsThe study included 589 fetuses, ranging from 26 to 40 weeks. Normal values (from 3rd to 97th percentile) are provided for each parameter. Interobserver agreement was excellent, with an intraclass correlation coefficient (ICC) > 0.75 for many parameters. The gender effect was evaluated in 372 cases and did not reveal any clinically meaningful difference. Comparison between the right and left cerebral hemispheres and between the right and left atria did not reveal any meaningful differences. Ultrasound and MRI measurements of BPD and TCD were compared in 94 cases and 48 cases, respectively, and the agreement was excellent (ICC = 0.85).ConclusionsWe present new reproducible reference charts for cerebral MRI biometry at 26–40 weeks' gestation, from a large cohort of fetuses. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.
Anatomic Significance of a Positive Barium Enema in Deep Infiltrating Endometriosis of the Large Bowel
Authors: Anaf Vincent , Nakadi Issam El , De Moor Veronique , Coppens Emmanuel , Zalcman Marc , Noel Jean‐Christophe 
Published: February 2009

AbstractPurposeThe anatomopathological significance of a positive double‐contrast barium enema (DCBE) for suspicion of deep infiltrating endometriosis of the large bowel was studied. This is a retrospective study of a prospective database.MethodsA large‐bowel resection was proposed for patients who were suspicious for large‐bowel endometriosis and had a positive DCBE. In a series of 73 patients, 71 large‐bowel resections were performed. Histology and immunohistochemistry with the monoclonal antibody CD‐10 were performed on the resection specimen. Outcome measures were the length of the resected specimen, the largest diameter of the lesion, the positivity of the resection margins, and the degree of infiltration of the large bowel. We also compared the mean largest diameters of the lesions with the degree of infiltration of the large bowel.ResultsBetween December 1997 and October 2005, 80 patients were suspicious for large‐bowel endometriosis: 73 (91%) had positive DCBEs, and 7 (9%) had negative DCBEs. Of the 73 with positive DCBEs, 4 (5%) refused digestive resection and 1 (1.4%) was excluded. Three patients underwent two large‐bowel resections because of the presence of bifocal lesions (left and right colon). A total of 71 resections were performed. In case of positive DCBE, the perivisceral fat and the whole muscularis were infiltrated in 100% of cases. The infiltration reached the submucosa and the mucosa respectively in 82% and 18% of cases. A total of 9.9% of resection margins were positive at histology but only focally. The mean largest diameter of the lesions infiltrating the whole thickness of the large bowel was not statistically different from the mean largest diameter of more superficial lesions.ConclusionsFindings of mass effect with indentations and ridging of the mucosa on DCBE in a setting suspicious for large‐bowel endometriosis correspond well with pathologic findings of deep infiltration of the large‐bowel wall. Clinicians dealing with deep infiltrating endometriosis should be aware of these findings, which could influence their choice of surgical treatment.
Does habitat structure matter? Spatially explicit population modelling of an Iberian gypsum endemic
Authors: Quintana‐Ascencio Pedro Francisco , Caballero Idoia , Olano José Miguel , Escudero Adrián , Albert Maria José 
Published: February 2009

AbstractHabitat heterogeneity may influence plant demography because conditions for survival, growth, and reproduction vary within a species’ range. We assessed the role of microhabitat spatial structure on the demography of Helianthemum squamatum, a shrubby gypsum specialist endemic to the Iberian Peninsula. We evaluated the demographic effect of microhabitat spatial variation using an approach that combined cellular automata with matrix population models, and included environmental and demographic stochasticty. We collected data on seed bank (2003–2005), seedling emergence (2003–2006), and adult survivorship (2004–2007) for H. squamatum in two independent blocks with different grazing intensity in Belinchón (Cuenca, Spain). We built spatial scenarios for each block based on field data of cover and spatial pattern of four microhabitats: lichenic crust, litter, H. squamatum, and shrub. Seedling survivorship was affected by year, block, and microhabitat, with individuals emerging under conspecifics having the highest survival rate and on litter the lowest in both blocks, whereas the effect of crust and other shrubs differed across blocks. Our models indicated population increase in the block with low grazing, but population decline in the block with intense grazing. We hypothesize that higher pressure of livestock grazing and trampling leads to a shift in relative microhabitat suitability for crust and shrub. This potential effect of grazing on spatial demographic variation opens interesting questions for future research. We emphasize the importance of considering microhabitat spatial structure when evaluating management and conservation strategies.
Brain dysfunction in phenylketonuria: Is phenylalanine toxicity the only possible cause?
Authors: van Spronsen F. J. , Hoeksma Marieke , Reijngoud Dirk‐Jan 
Published: February 2009

SummaryIn phenylketonuria, mental retardation is prevented by a diet that severely restricts natural protein and is supplemented with a phenylalanine‐free amino acid mixture. The result is an almost normal outcome, although some neuropsychological disturbances remain. The pathology underlying cognitive dysfunction in phenylketonuria is unknown, although it is clear that the high plasma concentrations of phenylalanine influence the blood–brain barrier transport of large neutral amino acids. The high plasma phenylalanine concentrations increase phenylalanine entry into brain and restrict the entry of other large neutral amino acids. In the literature, emphasis has been on high brain phenylalanine as the pathological substrate that causes mental retardation. Phenylalanine was found to interfere with different cerebral enzyme systems. However, apart from the neurotoxicity of phenylalanine, a deficiency of the other large neutral amino acids in brain may also be an important factor affecting cognitive function in phenylketonuria. Cerebral protein synthesis was found to be disturbed in a mouse model of phenylketonuria and could be caused by shortage of large neutral amino acids instead of high levels of phenylalanine. Therefore, in this review we emphasize the possibility of a different idea about the pathogenesis of mental dysfunction in phenylketonuria patients and the aim of treatment strategies. The aim of treatment in phenylketonuria might be to normalize cerebral concentrations of all large neutral amino acids rather than prevent high cerebral phenylalanine concentrations alone. In‐depth studies are necessary to investigate the role of large neutral amino acid deficiencies in brain.
PKU—What is daily practice in various centres in Europe?
Authors: van Spronsen F. J. , Ahring K. Kiær , Gizewska M. 
Published: February 2009

SummaryBackground:Since the start of the European Society of Phenylketonuria and Allied Disorders Treated as Phenylketonuria (ESPKU) in 1987, an increasing number of parental organizations of member countries have joined. Treatment varies widely within Europe. A survey among professionals was done to determine goals and practice.Method:In 2005, a questionnaire was sent to professionals of member countries, addressing diagnostic and treatment procedures, numbers of patients necessary for a PKU centre, guidelines followed, numbers of patients treated and professionals involved in care, target phenylalanine concentrations, amount of protein prescribed, frequency of monitoring and clinical visits, need for follow‐up of various clinical and biochemical data, the importance of various abnormalities, and definition of (non)compliance.Results:Seventeen centres of 12 countries answered. Professionals of 13 countries could not be reached or did not respond. Differences in care were observed in many issues of care including target phenylalanine concentrations. Only few issues had general consensus.Conclusion:Not all countries were really active at ESPKU level. In the active countries, a professional could not always be contacted. Responses show that PKU care varies largely between European countries. Notwithstanding the large diversity on many issues of day‐to‐day care and therapeutic targets, results showed increasing consensus on some issues. The most important outcome of this questionnaire might be that the Scientific Advisory Committee of the ESPKU initiated meetings for professionals of different backgrounds taking care of PKU patients besides the already existing programme for parents, patients and delegates. Discussion among these professionals may improve quality of care.
Chemical Composition and Nutritional Characteristics of the Seed Oil of Wild Lathyrus, Lens and Pisum Species from Southern Spain
Authors: Pastor‐Cavada Elena , Juan Rocio , Pastor Julio E. , Alaiz Manuel , Vioque Javier 
Published: February 2009

AbstractThe fatty acid composition of the seed oil of 19 wild legume species from southern Spain was analyzed by gas chromatography. The main seed oil fatty acids ranged from C14:0 to C20:0. Among unsaturated fatty acids, the most abundant were linoleic, oleic and linolenic acids, except for Lathyrus angulatus, L. aphaca, L. clymenum, L. sphaericus and L. nigricans where C18:3 contents were higher than C18:1 contents. Palmitic acid was the most abundant saturated acid in studied species, ranging from 11.6% in Lathyrus sativus to 19.3% in Lens nigricans. All studied species showed higher amounts of total unsaturated fatty acids than saturated ones. Among studied species, the ω6/ω3 ratio was variable, ranging from 2.0% in L. nigricans to 13.8% in L. sativus, there being eight species in which the ω6/ω3 ratio was below 5. The fatty acids observed in these plants supports the use of these plants as a source of important dietary lipids.
A rare pentad of foot and ankle deformities in hyperlax children
Authors: Ilyas I. , Wade W. J. , Al Barrag M. , Al Hussainan T. S. , lotaibi L. A. , Alssayad M. 
Published: February 2009

Objective The aim of this paper is to describe the clinical features and radiological appearance of a rare and complex lower leg and foot deformity in hyperlax children. Methods Four children were included in the study; of these, two had bilateral feet involvement. All deformities were present since birth, comprising a pentad of conditions: (1) pathologic external tibia and fibula torsion, (2) ball and socket ankle joint with medial subluxation and talus medial subluxation, (3) excessive hindfoot valgus, (4) peroneal and Achilles tendon displacement anterior to the lateral malleolus and (5) generalized ligament laxity. All children had failed cast manipulation. Only two had undergone a minimal soft tissue procedure, but there had been no improvement. Results All patients were ambulatory and pain free at the mean age of 6.5 years. Conclusion Conservative or minimal soft tissue procedures are not effective in restoring the anatomy of such feet.