bluuebunny/crossref_metadata_2025_split huggingface dataset:
Turbulent heat transfer enhancement in a triangular duct using delta‐winglet vortex generators
Authors: Althaher M.A. , Abdul‐Rassol A.A. , Ahmed H.E. , Mohammed H.A. 
Published: August 2011

AbstractThe augmentation of convective heat transfer of a turbulent flow using delta‐winglet vortex generators (VG) in a triangular duct was experimentally investigated. Two side walls of the heated test section are electrically heated with a constant heat flux while the lower wall is indirectly heated. Single, double, and triple pairs of VG are utilized. Each pair of VG was punched on one wall of the test duct. The effects of the number of VG pairs, the VG angle of attack, the VG location from the leading edge of the test duct, the VG geometry, and Reynolds number are examined in this paper. The results indicate that the Nusselt number and friction factor are relatively proportional to the size, number, and the inclination angle of the VG. The Nusselt number increases and the friction factor decreases as the Reynolds number increases. The present results were compared with the available literature and they show good agreement. Correlation equations of Nusselt number and friction factor for turbulent flow are developed, for the cases studied, as a function of Reynolds number and VG angle of attack. © 2011 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com/journal/htj). DOI 10.1002/htj.20382
Differential action of small molecule HER kinase inhibitors on receptor heterodimerization: Therapeutic implications
Authors: Sánchez‐Martín M. , Pandiella A. 
Published: August 2011

AbstractDeregulation of ErbB/HER receptor tyrosine kinases has been linked to several types of cancer. The mechanism of activation of these receptors includes establishment of receptor dimers. Here, we have analyzed the action of different small molecule HER tyrosine kinase inhibitors (TKIs) on HER receptor dimerization. Breast cancer cell lines were treated with distinct TKIs and the formation of HER2‐HER3 dimers was analyzed by coimmunoprecipitation and western blot or by Förster resonance energy transfer assays. Antibody‐dependent cellular cytotoxicity was analyzed by measuring the release of lactate dehydrogenase and cell viability. Lapatinib and neratinib interfered with ligand‐induced dimerization of HER receptors; while pelitinib, gefitinib, canertinib or erlotinib did not. Moreover, lapatinib and neratinib were able to disrupt previously formed receptor dimers. Structural analyses allowed the elucidation of the mechanism by which some TKIs prevent the formation of HER receptor dimers, while others do not. Experiments aimed at defining the functional importance of dimerization indicated that TKIs that impeded dimerization prevented down‐regulation of HER2 receptors, and favored the action of trastuzumab. We postulate that TKIs that prevent dimerization and down‐regulation of HER2 may augment the antitumoral action of trastuzumab, and this mechanism of action should be considered in the treatment of HER2 positive tumors which combine TKIs with antireceptor antibodies.
Mutations in SERPINF1 cause osteogenesis imperfecta type VI
Authors: Homan Erica P , Rauch Frank , Grafe Ingo , Lietman Caressa , Doll Jennifer A , Dawson Brian , Bertin Terry , Napierala Dobrawa , Morello Roy , Gibbs Richard , White Lisa , Miki Rika , Cohn Daniel H , Crawford Susan , Travers Rose , Glorieux Francis H , Lee Brendan 
Published: August 2011

Abstract
Osteogenesis imperfecta (OI) is a spectrum of genetic disorders characterized by bone fragility. It is caused by dominant mutations affecting the synthesis and/or structure of type I procollagen or by recessively inherited mutations in genes responsible for the posttranslational processing/trafficking of type I procollagen. Recessive OI type VI is unique among OI types in that it is characterized by an increased amount of unmineralized osteoid, thereby suggesting a distinct disease mechanism. In a large consanguineous family with OI type VI, we performed homozygosity mapping and next-generation sequencing of the candidate gene region to isolate and identify the causative gene. We describe loss of function mutations in serpin peptidase inhibitor, clade F, member 1 (SERPINF1) in two affected members of this family and in an additional unrelated patient with OI type VI. SERPINF1 encodes pigment epithelium–derived factor. Hence, loss of pigment epithelium–derived factor function constitutes a novel mechanism for OI and shows its involvement in bone mineralization. © 2011 American Society for Bone and Mineral Research
Geometric measures of large biomolecules: Surface, volume, and pockets
Authors: Mach Paul , Koehl Patrice 
Published: August 2011

AbstractGeometry plays a major role in our attempts to understand the activity of large molecules. For example, surface area and volume are used to quantify the interactions between these molecules and the water surrounding them in implicit solvent models. In addition, the detection of pockets serves as a starting point for predictive studies of biomolecule‐ligand interactions. The alpha shape theory provides an exact and robust method for computing these geometric measures. Several implementations of this theory are currently available. We show however that these implementations fail on very large macromolecular systems. We show that these difficulties are not theoretical; rather, they are related to the architecture of current computers that rely on the use of cache memory to speed up calculation. By rewriting the algorithms that implement the different steps of the alpha shape theory such that we enforce locality, we show that we can remediate these cache problems; the corresponding code, UnionBall has an apparent ${\cal O}$(n) behavior over a large range of values of n (up to tens of millions), where n is the number of atoms. As an example, it takes 136 sec with UnionBall to compute the contribution of each atom to the surface area and volume of a viral capsid with more than five million atoms on a commodity PC. UnionBall includes functions for computing analytically the surface area and volume of the intersection of two, three and four spheres that are fully detailed in an appendix. UnionBall is available as an OpenSource software. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Sequential IL‐23 and IL‐17 and increased Mmp8 and Mmp14 expression characterize the progression of an experimental model of periodontal disease in type 1 diabetes
Authors: Silva Juliete A.F. , Ferrucci Danilo L. , Peroni Luis A. , Abrahão Patrícia G.S. , Salamene Aline F. , Rossa‐Junior Carlos , Carvalho Hernandes F. , Stach‐Machado Dagmar R. 
Published: August 2011

AbstractMolecular mechanisms responsible for periodontal disease (PD) and its worsening in type 1 Diabetes Mellitus (DM1) remain unknown. Cytokine profile and expression levels of collagenases, Mmp14, and tissue inhibitors were determined, as were the numbers of neutrophils and macrophages in combined streptozotocin‐induced DM1 and ligature‐induced PD models. Increased IL‐23 (80‐fold) and Mmp8 expression (25‐fold) was found in DM1. Ligature resulted in an IL‐1β/IL‐6 profile, increased expression of Mmp8, Mmp13, and Mmp14 (but not Mmp1), and transient expression of Timp1 and Reck in non‐diabetics. PD in DM1 involved IL‐1β (but not IL‐6) and IL‐23/IL‐17, reduced IL‐6 and IL‐10, sustained Mmp8 and Mmp14, increased Mmp13 and reduced Reck expression in association with 20‐fold higher counts of neutrophils and macrophages. IL‐23 and Mmp8 expression are hallmarks of DM1. In association with the IL‐1/IL‐6 (Th1) response in PD, one found a secondary IL‐17 (Th17) pathway in non‐diabetic rats. Low IL‐6/TNF‐α suggest that the Th1 response was compromised in DM1, while IL‐17 indicates a prevalence of the Th17 pathway, resulting in high neutrophil recruitment. Mmp8, Mmp13, and Mmp14 expression seems important in the tissue destruction during PD in DM1. PD‐associated IL‐1/IL‐6 (Th1), IL‐10, and Reck expression are associated with the acute‐to‐chronic inflammation transition, which is lost in DM1. In conclusion, IL‐23/IL‐17 are associated with the PD progression in DM1. J. Cell. Physiol. 227: 2441–2450, 2012. © 2011 Wiley Periodicals, Inc.
Levels of Biological Organization and the Origin of Novelty
Authors: Hall Brian K. , Kerney Ryan 
Published: August 2011

AbstractThe concept of novelty in evolutionary biology pertains to multiple tiers of biological organization from behavioral and morphological changes to changes at the molecular level. Identifying novel features requires assessments of similarity (homology and homoplasy) of relationships (phylogenetic history) and of shared developmental and genetic pathways or networks. After a brief discussion of how novelty is used in recent literature, we discuss whether the evolutionary approach to homology and homoplasy initially formulated by Lankester in the 19th century informs our understanding of novelty today. We then discuss six examples of morphological features described in the recent literature as novelties, and assess the basis upon which they are regarded as novel. The six are: origin of the turtle shell, transition from fish fins to tetrapod limbs, origination of the neural crest and neural crest cells, cement glands in frogs and casquettes in fish, whale bone‐eating tubeworms, and the digestion of plant proteins by nematodes. The article concludes with a discussion of means of acquiring novel genetic information that can account for novelty recognized at higher levels. These are co‐options of existing genetic circuitry, gene duplication followed by neofunctionalization, gene rearrangements through mobile genetic elements, and lateral gene transfer. We conclude that on the molecular level only the latter category provides novel genetic information, in that there is no homologous precursor. However, novel phenotypes can be generated through both neofunctionalization and gene rearrangements. Therefore, assigning phenotypic or genotypic “novelty” is contingent on the level of biological organization addressed. J. Exp. Zool. (Mol. Dev. Evol.) 318B:428–437, 2012. © 2011 Wiley Periodicals, Inc.
Accurate low‐cost microwave component models using shape‐preserving response prediction
Authors: Koziel Slawomir 
Published: August 2011

SUMMARYA technique for accurate modeling of microwave components is presented. Our methodology exploits a recently introduced shape‐preserving response prediction (SPRP) technology, which is adopted here to work directly with electromagnetic simulation data of the device under consideration. Unlike in original SPRP, no low‐fidelity model is used, which simplifies implementation and makes our method applicable for a variety of microwave structures. SPRP allows us to create models at a low computational cost of a few electromagnetic simulations, which is convenient when solving various design tasks such as parametric optimization. As demonstrated using several test structures including microstrip filters and a planar antenna, the modeling accuracy is competitive to standard approximation techniques. Application examples for design optimization and statistical analysis are also provided. Copyright © 2011 John Wiley & Sons, Ltd.
Surgical resection for bulky or recurrent axillary metastatic melanoma
Authors: Shada Amber L. , Walters Dustin M. , Tierney Shannon N. , Slingluff Craig L. 
Published: August 2011

AbstractIntroductionMetastatic melanoma has few FDA approved treatments, and aggressive surgical resection has to be considered for management of bulky axillary metastases. We hypothesized that axillary resection in this setting is well tolerated and improves symptoms in the majority of patients.MethodsWe reviewed a prospectively collected database and identified 47 stage IIIC and IV patients with axillary nodal disease greater than 5 cm (68%), recurrent disease (36%), or disease adherent to axillary neurovascular structures (45%). Paresthesias, pain, and bleeding were present in 40% of patients, and were stable or improved after surgery in 75%. Most patients were asymptomatic prior to resection, and underwent resection for prevention of potential symptoms.ResultsMost patients underwent outpatient surgery. Postoperative complications included lymphedema (34%), range of motion limitation (23%), wound infection (17%), and neuropathic pain (17%). Among symptomatic patients, average time to progression was 3 months, compared to 9.5 months in asymptomatic patients (P = 0.08). Five‐year survival was lower (16%) in symptomatic patients than in asymptomatic patients (35%, P = 0.001).DiscussionSurgery for bulky axillary melanoma metastases is well tolerated, and should be considered in the management of Stage III or IV melanoma. Resection prior to symptoms may improve quality of life and is associated with longer survival. J. Surg. Oncol. 2012; 105:21–25. © 2011 Wiley Periodicals, Inc.
Optimisation of a solid‐phase microextraction method for the analysis of nicotine in hair
Authors: Brčić Karačonji Irena , Zimić Lukrica , Brajenović Nataša , Skender Ljiljana 
Published: August 2011

AbstractA headspace solid‐phase microextraction method (HS‐SPME) followed by gas chromatography with mass spectrometric detection (GC/MS) has been developed for the determination of low concentrations of nicotine in hair. Parameters affecting the SPME procedure including type of fiber coating, extraction mode, extraction temperature and time, desorption time, stirring, and salt addition have been evaluated and optimised. The method provided good linearity (r2≥0.9980) over the concentration range tested (0.2–20 ng/mg) and low detection limit (0.02 ng/mg). Precision expressed as relative standard deviation was <10%. The average accuracy was 95%. The proposed method was used to determine hair nicotine levels in 100 children in order to assess exposure to environmental tobacco smoke (ETS). The described HS‐SPME procedure is fast, simple, sensitive, and solvent‐free and is therefore suitable for studies involving ETS exposure assessment.
Characterization and identification of multiple constituents in Yinhuang granules by high‐performance liquid chromatography with diode‐array and time‐of‐flight mass spectrometry detection
Authors: Liu E‐Hu , Liu Qun , Chu Chu , Li Ping 
Published: August 2011

AbstractA fast high‐performance liquid chromatography (HPLC) method with diode‐array detection (DAD) and time‐of‐flight mass spectrometry (TOF/MS) has been developed for the analysis of multi‐constituent in Yinhuang granules, a well‐known combined herbal remedy prepared from the extract mixtures of Flos Lonicerae and Radix Scutellariae. The fast HPLC analysis was performed on an Agilent ZorBax SB‐C18 column (4.6×50 mm, 1.8 μm) and 0.2% aqueous formic acid and acetonitrile was the optimum mobile phase for gradient elution in 17 min, which is five times faster than the performance of conventional columns packed with 5.0 μm particles. With various fragmentor voltages in TOF/MS, accurate mass measurements (<5 ppm error) for molecular ions and characteristic fragment ions represented reliable identification criteria for different constituents. A total of 28 compounds, including nine phenolic acids, three iridoid glycosides and nine saponins from Flos Lonicerae and seven flavonoids from Radix Scutellariae, were identified or tentatively characterized in the extract of Yinhuang granules. The established fast HPLC‐DAD‐TOF/MS method turns out to be useful and efficient for quality control of this commonly used Chinese herbal preparation.
Polypyrrole/graphene composite‐coated fiber for the solid‐phase microextraction of phenols
Authors: Zou Jing , Song Xinhong , Ji Jiaojiao , Xu Weici , Chen Jinmei , Jiang Yaqi , Wang Yiru , Chen Xi 
Published: August 2011

AbstractA polypyrrole (Ppy)/graphene (G) composite was developed and applied as a novel coating for use in solid‐phase microextraction (SPME) coupled with gas chromatography (GC). The Ppy/G‐coated fiber was prepared by electrochemically polymerizing pyrrole and G on a stainless‐steel wire. The extraction efficiency of Ppy/G‐coated fiber for five phenols was the highest compared with the fibers coated with either Ppy or Ppy/graphene oxide (GO) using the same method preparation. Significantly, compared with various commercial fibers, the extraction efficiency of Ppy/G‐coated fiber is better than or comparable to 85 μm CAR/PDMS fiber (best extraction efficiency of phenol, o‐cresol, and m‐cresol in commercial fibers) and 85 μm polyacrylate (PA) fiber (best extraction efficiency of 2,4‐dichlorophenol and p‐bromophenol in commercial fibers). The effects of extraction and desorption parameters such as extraction time, stirring rate, and desorption temperature and time on the extraction/desorption efficiency were investigated and optimized. The calibration curves were linear from 10 to 1000 μg/L for o‐cresol, m‐cresol, p‐bromophenol, and 2,4‐dichlorophenol, and from 50 to 1000 μg/L for phenol. The detection limits were within the range 0.34–3.4 μg/L. The single fiber and fiber‐to‐fiber reproducibilities were <8.3 (n=7) and 13.3% (n=4), respectively. The recovery of the phenols spiked in natural water samples at 200 μg/L ranged from 74.1 to 103.9% and the relative standard deviations were <3.7%.
Corrosion resistance of 3,4‐dihydroxyphenylalanine/octadecylamine complex coatings on copper substrate
Authors: Xu F. Z. , Chen S. G. , Chen Y. Y. , Chen Y. 
Published: August 2011

AbstractOctadecylamine (ODA) film assisted with the preferential adhesion of poly‐DOPA was prepared on copper substrates by dip‐coating method. The DOPA self‐polymerized and adhered membrane was firmed to the copper substrate in mild aqueous alkaline environments. By immersing the substrate coated with poly‐DOPA in its absolute ethyl alcohol solution, ODA was adsorbed onto the substrate to give a hydrophobic surface. The formation and surface structure of the film were characterized by water contact angle measurement (DA), and scanning electron microscopy. The corrosion behavior of the functional hybrid films was evaluated by electrochemical impedance spectroscopy. Experimental results show that the impedance of the composite films reaches to 106 Ω, enhancing anti‐corrosion property of copper surface greatly.
Modeling of the material behavior during hot hydroforming
Authors: Elsenheimer D. , Taplick C. , Groche P. 
Published: August 2011

AbstractFor the purpose of numerically simulating metal forming processes, material data are necessary, determined by testing procedures similar to the particular process. The new technology of hot tube bulge tests has been introduced recently, fulfilling the requirements of material data determination for hot hydroforming. Based on measurement data gained by this technology, selected constitutive relations for approximating the flow stress depending on temperature, strain rate and logarithmic strain were parameterized applying linear regression analysis. Using the material law with the best approximation quality among the regarded equations, a numerical simulation of an exemplary forming process was accomplished. A comparison between the experimentally obtained geometry after a hot hydroforming process and the prediction by numerical analysis is used for evaluating the quality and applicability of the determined material data for this kind of process. Additionally, a process simulation, using extrapolated material data from compression tests is presented to visualize the influence of the testing procedure on the resulting part geometry prediction.
Effect of boron concentration on the solidification microstructure and properties of Fe‐Cr‐B alloy
Authors: Zhang H. , Fu H. , Jiang Y. , Guo H. , Lei Y. , Zhou R. , Cen Q. 
Published: August 2011

AbstractIn this article, the effect of boron concentration (B = 0, 0.4, 0.8, 1.4 and 2.0 respectively) on the solidification microstructure and properties of Fe‐Cr‐B alloy containing 0.35% C, 10–12% Cr, 0.5–0.8% Si, and 0.7–1.0% Mn was studied by means of the optical microscope (OM), the scanning electron microscope (SEM), X‐ray diffraction (XRD), Rockwell hardness and Vickers hardness tester. The results indicate that the microstructure of boron‐free sample consists of the martensite, and its hardness reaches 59.2 HRC. When a small amount of boron element was added, the eutectic phase of network structure generated along the grain boundary. The amount of eutectic phase increases when the boron concentration increases. Moreover, the eutectic phase is the mixture of boride and boron carbide. The boride is Fe2B and the boron carbide is (Cr, Fe)7(C, B)3. Compared with boron‐free sample, the Rockwell hardness of the samples with different boron concentrations are all higher, above 62 HRC, and the hardness grow up with the increase of boron concentration. When the boron concentration reaches to 1.4%, the Rockwell hardness of the alloy is 65.7 HRC, which is the highest in this study. When the boron concentration rises to 2.0%, the hardness has no obvious change.
Experimental and numerical investigations on powder pressing with superimposed oscillations of two materials
Authors: Behrens B.‐A. , Seidel H.‐J. , Lange F. , Kammler M. 
Published: August 2011

AbstractDem Pressvorgang ist in der Fertigungskette zur Herstellung pulvertechnisch hergestellter Bauteile eine besondere Bedeutung beizumessen, da in dieser Fertigungsstufe die Dichteverteilung und somit die spezifischen Eigenschaften maßgeblich bestimmt werden. Insbesondere die beim Pressen zwangsläufig auftretende Reibung zwischen den formgebenden Werkzeugen und dem Pulverkörper führt zu Dichtegradienten, die ihrerseits zu Sinterverzügen und somit auch zu inhomogenen Werkstoffeigenschaften innerhalb des Bauteils führen. Das Ziel der hier vorgestellten Arbeit bestand daher in der gezielten Erprobung des schwingungsüberlagerten Pressens zur Fertigung pulvertechnisch hergestellter Bauteile, um reibungsbedingte Dichtegradienten zu reduzieren. Es wurden sowohl ein Aluminiumpulver (Alumix 13 der Fa. ECKA) als auch ein Gemenge aus Schleif‐ und Bindemittel (Fa. Comet Schleifscheiben) untersucht, wie es zur Fertigung keramisch gebundener Schleifkörper eingesetzt wird. Die Ergebnisse geben werkstoffabhängig unterschiedliche Hinweise für die positiven Auswirkungen einer Schwingungsüberlagerung des Pressvorgangs. So konnte die Existenz einer günstigen Überlagerungsfrequenz gezeigt werden, die für das untersuchte Gemenge aus Schleif‐ und Bindemittel im Bereich um 60 Hz liegt. Des Weiteren zeigte sich mittels experimenteller und numerischer Untersuchungen, dass durch die Wahl einer geeigneten Überlagerungsfrequenz Dichteverteilungen erzielbar sind, wie sie sich sonst nur beim technisch deutlich aufwändigeren zweiseitigen Pressen einstellen.