bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surface modification of Aramid fibers with new chemical method for improving interfacial bonding strength with epoxy resin
Authors: Liu Tie‐Min , Zheng Yuan‐Suo , Hu Jie 
Published: June 2010

AbstractFriedel‐Crafts reaction was elected as the specific chemical approach to modify Aramid fiber surface in this article. After the surface treatment, the interfacial shear strength value of Aramid fiber/Epoxy composites was enhanced by about 50%. The surface elements of Aramid fibers were determined by X‐ray photoelectron spectroscopy, whose results showed that the ratio of Oxygen/Carbon was increased. The crystalline state of Aramid fibers was determined by X‐ray diffraction instrument, and the surface morphological of Aramid fibers was analyzed by Scanning electron microscope. The results indicated that this novel surface treatment approach, which is a suitable way of the batch‐process for Industrialization, not only can improve the interfacial bonding strength of Aramid fibers reinforced Epoxy resin matrix composites remarkably, but also hardly has any negative influence on the intrinsic tensile strength of Aramid fibers. The wettability degree of the fiber surface was enhanced by this new approach too. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of iron carboxylates on the photodegradability of polypropylene. I. Natural weathering studies
Authors: Rajakumar K. , Sarasvathy V. , Thamaraichelvan A. , Chitra R. , Vijayakumar C. T. 
Published: June 2010

AbstractTo enhance the photodegradability of polypropylene (PP), various carboxylates of iron, including ferric caprate (MF03), ferric laurate (MF04), ferric myristate (MF05), ferric palmitate (MF06), and ferric stearate (MF07), were synthesized. Virgin PP was blended with the synthesized prodegradants (0.2%) and blown into films. To study the photodegradation behavior of PP with and without the prodegradants under natural weathering conditions, all of the films were exposed to sunlight according to the procedure of ASTM 1435. All of the weathered films were found to degrade after a certain number of days of exposure; this was found from the steep increases in the carbonyl, hydroperoxide, hydroxyl, lactone, ester, carboxylic acid, and crystallinity indices. At the same time, a sudden decrease in the elongation at break percentages and tensile strength and surface cracks were also observed. PP containing the prodegradants degraded at a faster rate than the virgin material. The time taken for the material to lose half of the elongation at break value was taken as the half‐time, and this was used to determine the effectiveness of the prodegradants. The effectiveness of the prodegradants for the photodegradation of PP was found to be in the following order: MF03 > MF04 > MF05 > MF06 > MF07. With increasing alkyl chain length of the prodegradants, the stability of the alkyl radical increased, whereas the mobility of the radical in the PP matrix decreased. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
The effect of pigments on the stability of silicone/montmorillonite prosthetic nanocomposites
Authors: Vasilakos Sozon P. , Tarantili Petroula A. 
Published: June 2010

AbstractThe purpose of this investigation was to evaluate the protection provided to silicone by pigments, such as dry earth pigments. In addition, the effect of nanostructured and organically modified montmorillonite fillers on the overall behavior of reinforced systems was explored. To obtain relevant data and, furthermore, to reveal possible mechanisms of structural changes that could influence silicone stability, pure and reinforced silicon elastomers were mixed with various colorants and studied for their stability to accelerating aging, during the exposure to UV radiation and humidity. A number of tests were run such as, Attenuated Total Reflectance, Fourier Transform Infrared Spectroscopy (ATR‐FTIR), Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), and Tensile measurements. Swelling in toluene and color tests were also carried out. The experimental results showed that the UV aging of silicone elastomers results in chain scission and cross‐linking rather than formation of oxygen containing groups. The main conclusion of this work is montmorillonite acts as a significant reinforcement and protects silicone against degradation during exposure to UV irradiation. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effects of the content of silane coupling agent KH‐560 on the properties of LLDPE/magnesium hydroxide composites
Authors: Yang Zhen , Cai Jun , Zhou Chengang , Zhou Dao , Chen Bifeng , Yang Hu , Cheng Rongshi 
Published: June 2010

AbstractBased on traditional idea of molecular coupling effect, surface modifiers were helpful to improve the performances of inorganic/organic composites. However, it was also widely accepted that the content of surface modifier should be controlled in a suitable range, and more or less modifiers could not reach to optimal properties. The intrinsic reason for this phenomenon was not clear until now. In this article, the influences of the content of surface modifier: silane coupling agent KH‐560, on the final performances of linear low‐density polyethylene (LLDPE)/magnesium hydroxide (MH) composites, have been studied. The performance tests of LLDPE/MH composites, including mechanical properties measurements, thermal oxidative stability analysis, and surface morphology observation, all confirmed that there was an optimal content range of surface modifier. However, further morphology investigation of the modified MH by particle size and particle size distribution analyzer showed that, the particle size and particle size distribution of MH both increased as the content of KH‐560 increased. ATR‐FTIR analysis proved that silane grafting was achieved on the MH particle surface, which not only improved the compatibility between MH and LLDPE for molecular coupling effect, but also caused bigger particle size and wider particle size distribution, which were disadvantageous to improve the performances of the composites. The two opposite effects of the surface modifiers mentioned above affected the final performances of the composites. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of fiber orientation on pore size characteristics of nonwoven structures
Authors: Rawal Amit , Kameswara Rao P. V. , Russell Stephen , Jeganathan Arjun 
Published: June 2010

AbstractFiber orientation is a key parameter affecting the geometrical, hydraulic and mechanical properties of nonwoven materials. The effect of fiber orientation on the pore size has been experimentally investigated based on air‐laid, parallel‐laid, and cross‐laid structures following through‐air bonding. It was evident that there is a discernible difference between the mean flow and maximum pore sizes of these nonwoven materials. The influence on pore size was further elucidated by evaluating experimental and theoretical models based on sieving‐percolation pore network theory including a model that incorporates directional parameter to account for the effect of fiber orientation. It was established that good agreement with experimental data can be obtained using such a model. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
High dispersion ability of fluorene‐based polyester as a polymer matrix for carbon nanotubes
Authors: Kawasaki Shinichi , Yamada Masahiro , Kobori Kana , Jin Fengzhe , Takata Toshikazu 
Published: June 2010

AbstractThe high compatibility of fluorene‐based polyester (FBP‐HX) as a polymer matrix for multiwalled carbon nanotubes (MWCNTs) is discussed. A low surface resistivity due to the fine dispersion of MWCNTs in FBP‐HX and polycarbonate (PC) is reported. With a solution‐casting method, a percolation threshold with the addition of between 0.5 and 1.0 wt % MWCNTs was observed in the MWCNT/PC and MWCNT/FBP‐HX composites. Because of the coverage of FBP‐HX on the MWCNTs, a higher surface resistivity and a higher percolation ratio of the MWCNT/FBP‐HX composites were achieved compared with the values for the MWCNT/PC composites. In the MWCNT/FBP‐HX composites, MWCNTs covered with FBP‐HX were observed by scanning electronic microscopy. Because of the coverage of FBP‐HX on the MWCNTs, FBP‐HX interfered with the electrical pathway between the MWCNTs. The MWCNTs in FBP‐HX were covered with a 5‐nm layer of FBP‐HX, but the MWCNTs in the MWCNT/PC composites were in their naked state. MWCNT/PC sheets demonstrated the specific Raman absorption of the MWCNTs only with the addition of MWCNTs of 1 wt % or above because of the coverage of the surface of the composite sheet by naked MWCNTs. In contrast, MWCNT/FBP‐HX retained the behavior of the matrix resin until a 3 wt % addition of MWCNTs was reached because of the coverage of MWCNTs by the FBP‐HX resin, induced by its high wettability. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Abdominal adiposity in rheumatoid arthritis: Association with cardiometabolic risk factors and disease characteristics
Authors: Giles Jon T. , Allison Matthew , Blumenthal Roger S. , Post Wendy , Gelber Allan C. , Petri Michelle , Tracy Russell , Szklo Moyses , Bathon Joan M. 
Published: June 2010

AbstractObjectiveAbdominal adiposity, especially visceral adiposity, is emerging as a recognized cardiometabolic risk factor. This study was undertaken to investigate how abdominal fat is distributed in rheumatoid arthritis (RA), and its RA‐related determinants.MethodsMen and women with RA were compared with non‐RA controls from the Multi‐Ethnic Study of Atherosclerosis. Participants underwent anthropometric studies and quantification of visceral and subcutaneous fat areas (VFA and SFA) using abdominal computed tomography.ResultsA total of 131 RA patients were compared with 121 controls. Despite similar body mass index and waist circumference between the RA and control groups, the adjusted mean VFA was 45 cm2 higher (+51%) in male RA patients versus male controls (P = 0.005), but did not significantly differ by RA status in women. The adjusted mean SFA was 119 cm2 higher (+68%) in female RA patients versus female controls (P < 0.001), but did not significantly differ by RA status in men. Elevated VFA (≥75th percentile) was associated with a significantly higher adjusted probability of having an elevated fasting glucose level, hypertension, or meeting the composite definition of the metabolic syndrome in the RA group compared with controls. Within the RA group, rheumatoid factor seropositivity and higher cumulative prednisone exposure were significantly associated with a higher mean adjusted VFA. Higher C‐reactive protein levels and lower Sharp/van der Heijde scores were significantly associated with both VFA and SFA.ConclusionThe distribution of abdominal fat differs significantly by RA status. Higher VFA in men with RA, and the more potent association of VFA with cardiometabolic risk factors in men and women with RA, may contribute to cardiovascular risk in RA populations.
Knockdown of Fcγ receptor III in an arthritic temporomandibular joint reduces the nociceptive response in rats
Authors: Kramer Phillip R. , Puri Jyoti , Bellinger Larry L. 
Published: June 2010

AbstractObjectiveFcγ receptor III (FcγRIII; CD16) is a receptor expressed on immune cells that selectively binds IgG molecules. IgG binding results in cellular activation and cytokine release. IgG is an important factor in arthritis and can be found in the arthritic temporomandibular joint (TMJ). We undertook this study to test the hypothesis that a reduction in FcγRIII expression in TMJ tissues would reduce the nociceptive and inflammatory responses in an inflamed joint.MethodsSmall interfering RNA (siRNA), either naked or complexed with linear polyethyleneimine, was injected into the superior joint space of the TMJ in rats. After administration of siRNA the joint was injected with saline or with Freund's complete adjuvant to induce arthritis. Nociceptive responses were quantitated in the rat by measuring the animal's meal duration. FcγRIII expression in the TMJ tissue was assayed by immunocytochemistry or Western blotting. Cleavage of FcγRIII transcript was then assayed by 5′ rapid amplification of complementary DNA ends. Interleukin‐1β (IL‐1β) and IgG content was measured in the TMJ tissue by enzyme‐linked immunosorbent assay.ResultsInjection of FcγRIII siRNA reduced the amount of FcγRIII in the TMJ tissues, and the transcript was cleaved in a manner consistent with an RNA interference mechanism. Moreover, injection of FcγRIII siRNA reduced the nociceptive response of rats with an arthritic TMJ and reduced the amount of the proinflammatory cytokine IL‐1β.ConclusionFcγRIII contributes to the pain resulting from inflammatory arthritis of the TMJ, and siRNA has the potential to be an effective treatment for this disorder.
Cecr2 mutations causing exencephaly trigger misregulation of mesenchymal/ectodermal transcription factors
Authors: Fairbridge Nicholas A. , Dawe Christine E. , Niri Farshad H. , Kooistra Megan K. , King‐Jones Kirst , McDermid Heather E. 
Published: June 2010

AbstractBACKGROUND: Over 200 mouse genes are associated with neural tube defects (NTDs), including Cecr2, the bromodomain‐containing subunit of the CERF chromatin remodeling complex. METHODS: Gene‐trap mutation Cecr2Gt45Bic results in 74% exencephaly (equivalent of human anencephaly) on the BALB/c strain. Gene expression altered during cranial neural tube closure by the Cecr2 mutation was identified through microarray analysis of 11–14 somites stage Cecr2Gt45Bicembryos. RESULTS: Analysis of Affymetrix Mouse 430 2.0 chips detected 60 transcripts up‐regulated and 54 transcripts down‐regulated in the Cecr2Gt45Bic embryos (fold > 1.5, p < 0.05). The Cecr2 transcript was reduced only ∼7‐ to 14‐fold from normal levels, suggesting the Cecr2Gt45Bic is a hypomorphic mutation. We therefore generated a novel Cecr2 null allele (Cecr2
tm1.1Hemc). Resulting mutants displayed a stronger penetrance of exencephaly than Cecr2Gt45Bic in both BALB/c and FVB/N strains, in addition to midline facial clefts and forebrain encephalocele in the FVB/N strain. The Cecr2 transcript is reduced 260‐fold in the Cecr2tm1.1Hemc line. Subsequent qRT‐PCR using Cecr2
tm1.1Hemc mutant heads confirmed downregulation of transcription factors Alx1/Cart1,
Dlx5, Eya1, and Six1. CONCLUSIONS: As both Alx1/Cart1 and Dlx5 mouse mutations result in exencephaly, we hypothesize that changes in expression of these mesenchymal/ectodermal transcription factors may contribute to NTDs associated with Cecr2. Birth Defects Research (Part A), 2010. © 2010 Wiley‐Liss, Inc.
Challenges to multiple testing in clinical trials
Authors: James Hung H. M. , Wang Sue‐Jane 
Published: June 2010

AbstractMultiple testing problems are complex in evaluating statistical evidence in pivotal clinical trials for regulatory applications. However, a common practice is to employ a general and rather simple multiple comparison procedure to handle the problems. Applying multiple comparison adjustments is to ensure proper control of type I error rates. However, in many practices, the emphasis of the type I error rate control often leads to a choice of a statistically valid multiple test procedure but the common sense is overlooked. The challenges begin with confusions in defining a relevant family of hypotheses for which the type I error rates need to be properly controlled. Multiple testing problems are in a wide variety, ranging from testing multiple doses and endpoints jointly, composite endpoint, non‐inferiority and superiority, to studying time of onset of a treatment effect, and searching for minimum effective dose or a patient subgroup in which the treatment effect lies. To select a valid and sensible multiple test procedure, the first step should be to tailor the selection to the study questions and to the ultimate clinical decision tree. Then evaluation of statistical power performance should come in to play in the next step to fine tune the selected procedure.
Membrane binding and perturbation studies of the antimicrobial peptides caerin, citropin, and maculatin
Authors: Brian Chia C. S. , Gong Yujing , Bowie John H. , Zuegg Johannes , Cooper Matthew A. 
Published: June 2010

AbstractCitropin 1.1, maculatin 1.1, and caerin 1.1 are short antibacterial cationic peptides from the skin glands of the Australian tree frog Litoria species. Several analogues have been synthesized to give a better insight into the relationship between the structure of the peptides and their antibacterial and haemolytic activity. Binding studies using a surface plasmon resonance (SPR) biosensor together with a vesicle‐capture sensor chip have been used to investigate selectivity of the peptides and their analogues for 1,2‐dimyristoyl‐sn‐glycero‐3‐phosphoglycerol (DMPG) and 1,2‐dimyristoyl‐sn‐glycero‐3‐phosphocholine (DMPC) vesicles, as well as for vesicles made from lipid extracts from Escherichia coli and bovine brain. Data obtained for membrane selectivity using natural lipid extracts show better correlation with minimum inhibitory concentration (MIC) values against Gram‐positive bacteria and haemolytic activity than that obtained using synthetic DMPG and DMPC. Electron microscopy and membrane leakage studies using Gram‐positive bacteria gave further insight into the membrane disruption properties of the peptides. For maculatin 1.1, it was found that the central proline residue, which is responsible for a bend in the α‐helical structure, is essential not only for the antibacterial activity but also for binding, and perturbation of membranes. The caerin analogues showed only small variations in their MIC values and membrane binding. In contrast, for citropin 1.1, the analogue replacing the aspartate with a lysine showed the lowest MIC against Gram‐positive bacteria and best membrane binding to E. coli lipid extracts, coinciding with an increased hydrophobic moment of the peptide. These data give further insight into these antimicrobial natural products, toward the development and evaluation of these and other analogues as potential antibiotics. © 2010 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 96:147–157, 2011.
Continuous scalable blood filtration device using inertial microfluidics
Authors: Mach Albert J. , Di Carlo Dino 
Published: June 2010

AbstractCell separation is broadly useful for applications in clinical diagnostics, biological research, and potentially regenerative medicine. Recent attention has been paid to label‐free size‐based techniques that may avoid the costs or clogging issues associated with centrifugation and mechanical filtration. We present for the first time a massively parallel microfluidic device that passively separates pathogenic bacteria cells from diluted blood with macroscale performance. The device was designed to process large sample volumes in a high‐throughput, continuous manner using 40 single microchannels placed in a radial array with one inlet and two rings of outlets. Each single channel consists of a short focusing, gradual expansion and collection region and uses unique differential transit times due to size‐dependent inertial lift forces as a method of cell separation. The gradual channel expansion region is shown to manipulate cell equilibrium positions close to the microchannel walls, critical for higher efficiency collection. We demonstrate >80% removal of pathogenic bacteria from blood after two passes of the single channel system. The massively parallel device can process 240 mL/h with a throughput of 400 million cells/min. We expect that this parallelizable, robust, and label‐free approach would be useful for filtration of blood as well as for other cell separation and concentration applications from large volume samples. Biotechnol. Bioeng. 2010;107: 302–311. © 2010 Wiley Periodicals, Inc.
Design of cellular porous biomaterials for wall shear stress criterion
Authors: Chen Yuhang , Zhou Shiwei , Cadman Joseph , Li Qing 
Published: June 2010

AbstractThe microfluidic environment provided by implanted prostheses has a decisive influence on the viability, proliferation and differentiation of cells. In bone tissue engineering, for instance, experiments have confirmed that a certain level of wall shear stress (WSS) is more advantageous to osteoblastic differentiation. This paper proposes a level‐set‐based topology optimization method to regulate fluidic WSS distribution for design of cellular biomaterials. The topological boundary of fluid phase is represented by a level‐set model embedded in a higher‐dimensional scalar function. WSS is determined by the computational fluid dynamics analysis in the scale of cellular base cells. To achieve a uniform WSS distribution at the solid–fluid interface, the difference between local and target WSS is taken as the design criterion, which determines the speed of the boundary evolution in the level‐set model. The examples demonstrate the effectiveness of the presented method and exhibit a considerable potential in the design optimization and fabrication of new prosthetic cellular materials for bioengineering applications. Biotechnol. Bioeng. 2010;107:737–746. © 2010 Wiley Periodicals, Inc.
Efficient phase separation and product recovery in organic‐aqueous bioprocessing using supercritical carbon dioxide
Authors: Brandenbusch Christoph , Bühler Bruno , Hoffmann Philip , Sadowski Gabriele , Schmid Andreas 
Published: June 2010

AbstractBiphasic hydrocarbon functionalizations catalyzed by recombinant microorganisms have been shown to be one of the most promising approaches for replacing common chemical synthesis routes on an industrial scale. However, the formation of stable emulsions complicates downstream processing, especially phase separation. This fact has turned out to be a major hurdle for industrial implementation. To overcome this limitation, we used supercritical carbon dioxide (scCO2) for both phase separation and product purification. The stable emulsion, originating from a stereospecific epoxidation of styrene to (S)‐styrene oxide, a reaction catalyzed by recombinant Escherichia coli, could be destabilized efficiently and irreversibly, enabling complete phase separation within minutes. By further use of scCO2 as extraction agent, the product (S)‐styrene oxide could be obtained with a purity of 81% (w/w) in one single extraction step. By combining phase separation and product purification using scCO2, the number of necessary workup steps can be reduced to one. This efficient and easy to use technique is generally applicable for the workup of biphasic biocatalytic hydrocarbon functionalizations and enables a cost effective downstream processing even on a large scale. Biotechnol. Bioeng. 2010;107:642–651. © 2010 Wiley Periodicals, Inc.