bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of Stress Corrosion Cracking Characteristics of CP Ti, Ti-6AI-7Nb, Ti-6AI-4V, and Ti-15IVIo
Authors: Williamson RS , Roach MD , Zardiackas LD 
Published: April 2008

The purpose of this research was to evaluate and compare the stress corrosion cracking (SCC) of Ti-15 Mo (ASTM F2066), Ti-6Al-7Nb (ASTM1295), Ti-6A1-4V ELI (ASTM F136), and Grade 4 CPTi (ASTM F67). Evaluation of alloy composition, microstructure, Vickers microhardness, and tensile properties was performed to determine compliance with the appropriate ASTM specification. For SCC testing, smooth tensile samples with a gauge length of 10 mm and a gauge diameter of 4 mm and notched samples with a notch root diameter of 4 mm (Kt=3.2) were prepared using low stress grinding procedures. Three smooth and three notched samples were tested in distilled HiO and Ringer's solution at 37°C. Testing was performed using the slow extension rate method at a stroke rate of 10-5 mm/s according to the guidelines established in ASTM G129. The ratio of the percent elongation (PER) and reduction of area (ROAR) of smooth and notched samples tested in Ringer's solution and distilled water were evaluated. The fracture surfaces of representative samples were also examined for fracture mode identification using SEM.
Results showed that all alloys complied with the appropriate ASTM specification. SCC may be considered to occur in a material if the ductile properties in an aggressive media are inferior to the ductile properties in a non-aggressive media. Evaluations of the PER and ROAR ratios in smooth and notched samples for each alloy in Ringer's and distilled water showed no indication of SCC failure mechanisms. SEM examination of the fracture surfaces showed no differences in the fracture morphology regardless of the testing solution. These results were consistent with the mechanical testing data. It is therefore concluded that SCC mechanisms were not operating or contributing to the fracture of these alloys under the conditions evaluated.
Bone Marrow-Derived Mesenchymal Stem Cells Ameliorate Autoimmune Enteropathy Independently of Regulatory T Cells
Authors: Parekkadan Biju , Tilles Arno W. , Yarmush Martin L. 
Published: April 2008

Abstract
Cell-based tolerogenic therapy is a relatively new approach for the treatment of autoimmune diseases. Mesenchymal stem cells (MSCs) have been shown to be potent immunomodulatory agents in a number of experimental and clinical scenarios; however, their use in various autoimmune diseases is undefined. Herein, we report the efficacy of MSC transplantation in a multiorgan autoimmunity model. Mice with defective peripheral tolerance caused by a deficiency in regulatory T cells were used as a testbed for therapy. After screening multiple target tissues of autoimmune attack, we observed an MSC-specific improvement in the histopathology of the distal ileum of treated mice. We then showed that MSCs can reduce mesenteric lymph node (MLN) cellularity in autoimmune mice during active disease and decrease activated T-cell populations in the MLN. Trafficking studies using enhanced green fluorescent protein (eGFP)-reporter MSCs revealed no appreciable engraftment in the intestine, but it did reveal the presence of eGFP+ cells organized in clusters within the MLN, as well as ancillary nodes. Semiquantitative analysis showed no difference in the number of clusters; however, eGFP+ cells in MLNs compared with ancillary nodes had distinct fibroblastoid morphology and formed a network with neighboring eGFP+ cells. Finally, we show evidence that transplantation of MSCs caused global immunosuppression, as measured by increased CD4+ CD8+ thymocyte production and serum interleukin-10 and decreased serum interferon-γ. These data implicate the intestine as a new site of MSC tolerance induction and should motivate additional studies evaluating the use of MSCs as a treatment for autoimmune enteropathies.
Disclosure of potential conflicts of interest is found at the end of this article.
Acute toxicity of thioarsenates to Vibrio fischeri
Authors: Planer-Friedrich Britta , Franke Doreen , Merkel Broder , Wallschläger Dirk 
Published: April 2008

Abstract
Thioarsenic species often are the predominant arsenic species in sulfidic environments, yet little is known about their toxicity. We report to our knowledge the first determination of acute toxicity of mono-, di-, and trithioarsenate to the bioluminescent bacterium Vibrio fischeri, which increases with an increasing number of thio(SH)-groups. Whereas mono- and dithioarsenate are much less toxic (effective analyte concentration causing a 50% decrease in luminescence [EC50], 676 and 158 mg/L, respectively), the toxicity of trithioarsenate (EC50, 14.4 mg/L) is comparable to the toxicities of arsenate and arsenite (EC50, 9.1 and 26.1 mg/L, respectively). The low toxicity of monothioarsenate is remarkable, because it has chemical properties very similar to those of arsenate. In contrast to the toxicities of arsenite and arsenate, the toxicity of thioarsenates increases with exposure time, suggesting a lack of detoxification mechanisms or a conversion of thioarsenic species into arsenic oxyanions after uptake. We determined the acute toxicity of synthetic arsenite solutions with varying sulfide concentration to V. fischeri. Arsenic speciation in these solutions was measured by ion chromatography–inductively coupled plasma–mass spectrometry, and the observed toxicity was related to the different arsenic species present. High inhibition of luminescence was observed at low and high ratios of sulfur to arsenic, in which arsenite or a mixture of di-, tri-, and tetrathioarsenate dominated arsenic speciation. Acute toxicity decreased at sulfur to arsenic ratios of from 1 to 10, with a minimum luminescence inhibition of 30% at a ratio of 3.5, at which concentrations of 55 mg/L of arsenite and 30 mg/L of trithioarsenate were determined. The toxicity observed under these conditions is much lower than that anticipated from the individual dose–response curves that predict each species alone already should cause 70 to 80% inhibition. The low toxicity suggests an antagonistic toxicological interaction between arsenite and trithioarsenate.
Dipeptidyl Peptidase-IV Inhibitors: Pharmacological Profile and Clinical Use
Authors: White John R. 
Published: April 2008

IN BRIEF
Sitagliptin is the first agent in a new category of medications, the dipeptidyl peptidase-IV (DPP-IV) inhibitors. It was recently approved in the United States for the management of hyperglycemia in patients with type 2 diabetes; vildagliptin, a second agent in this class, is likely to join it on the U.S. market soon. These compounds accentuate the activity of endogenously produced antihyperglyemic incretin hormones and are generally well tolerated. This article provides an overview of the pharmacology and clinical use of the DPP-IV inhibitors.
Use of FM1‐43 and Other Derivatives to Investigate Neuronal Function
Authors: Cousin Michael A. 
Published: April 2008

AbstractThe fluorescent dye FM1‐43 and its derivatives can be used to monitor the physiology of synaptic vesicle turnover in central nerve terminals. They do so by their ability to reversibly partition into membranes, a process that results in a huge increase in fluorescence in comparison to their quantum yield in solution. This unit provides protocols for quantifying total synaptic vesicle turnover, the kinetics and extent of synaptic vesicle exocytosis, and the kinetics and mode of synaptic vesicle endocytosis. Descriptions of other ways these protocols have been used to derive information about the life cycle of the synaptic vesicle are also provided. Curr. Protoc. Neurosci. 43:2.6.1‐2.6.12. © 2008 by John Wiley & Sons, Inc.
Ballistic Labeling with Fluorescent Dyes and Indicators
Authors: Morgan Joshua L. , Wong Rachel O.L. 
Published: April 2008

AbstractNeuronal cell labeling is fundamental to investigations of the nervous system. Labeling of cells in live or fixed tissue with dyes or ion indicators using ballistic approaches has recently been developed for the study of neuronal architecture and function. In this approach, dye‐coated particles are propelled into cells by a pulse of pressurized helium. This unit provides step‐by‐step protocols for coating tungsten particles with fluorescent or indicator dyes and for delivering these particles into cells and tissue. The major advantage of the ballistic method of dye delivery is that large populations of neurons can be rapidly labeled within a piece of live or fixed tissue. Advantages and limitations of the approach are discussed and technical advice is provided. Curr. Protoc. Neurosci. 43:2.11.1‐2.11.10. © 2008 by John Wiley & Sons, Inc.
Growth and Manipulation of Yeast
Authors: Treco Douglas A. , Winston Fred 
Published: April 2008

AbstractYeast cultures can be grown, maintained, and stored in liquid media or on agar plates using techniques similar to those for bacterial cultures. This unit describes culture conditions for these basic techniques. Additional methods describe determination of yeast mating type, diploid construction, sporulation, tetrad dissection, and random spore analysis. Curr. Protoc. Mol. Biol. 82:13.2.1‐13.2.12. © 2008 by John Wiley & Sons, Inc.
In Situ Polymerase Chain Reaction and Hybridization to Detect Low‐Abundance Nucleic Acid Targets
Authors: Bagasra Omar 
Published: April 2008

AbstractThis unit provides detailed methods and material descriptions for in situ hybridization following in situ amplification of DNA or RNA by PCR. It includes all essential components of the techniques, including variations suitable for different kinds of tissue and cell preparations. Planning, controls, and critical parameters for the amplification steps are discussed. Curr. Protoc. Mol. Biol. 82:14.8.1‐14.8.28. © 2008 by John Wiley & Sons, Inc.
Laboratory Safety
Authors: Meisenhelder Jill , Bursik Steve , Lunn George , Strober Warren 
Published: April 2008

AbstractThe pursuit of scientific knowledge has been considerably advanced by the use of a wide variety of hazardous substances, including radioisotopes, hazardous chemicals, and biohazards. This appendix addresses each of these classes of hazards and primary safety precautions that need to be considered. Curr. Protoc. Hum. Genet. 57:A.2A.1‐A.2A.10. © 2008 by John Wiley & Sons, Inc.
Fabrication of Hairy Polymeric Films Inspired by Geckos: Wetting and High Adhesion Properties
Authors: Cho Woo Kyung , Choi Insung S. 
Published: April 2008

AbstractIn this paper, we report a facile and efficient method for fabricating gecko‐inspired, hairy hard poly(dimethylsiloxane) (h‐PDMS) structures, composed of nanopillars with controllable lengths. The structures are generated by utilizing an anodic aluminum oxide (AAO) membrane as a replication template. For easy handling of the replicated h‐PDMS films, the vinyl‐terminated glass substrate is used. The cross‐linking between the vinyl moieties on the glass surface and methylhydrosiloxanes, one of the h‐PDMS components, makes it easy to transfer the molded h‐PDMS layer from the AAO template to the glass. The resulting hairy h‐PDMS‐coated glass surface shows both the static water contact angle as high as 150.5° ± 0.4° (superhydrophobicity) and high adhesion to water. A water droplet placed on the h‐PDMS surface does not slide, even when the surface is tilted vertically or turned upside down. We believe that the densely packed h‐PDMS nanopillars (2.6 × 106 pillars mm−2) are the key contributor to the observed high adhesion, presumably by generating large van der Waals' forces from the large surface area in very close contact with water. The adhesion force of the surface is found to be strong enough to catch a water droplet that rolls down fast on a tilted self‐cleaning surface. In addition to water, the wetting and high adhesion properties of the molded nanopillar h‐PDMS films are also investigated with several organic liquids.
Initiated and Oxidative Chemical Vapor Deposition of Polymeric Thin Films: iCVD and oCVD
Authors: Tenhaeff Wyatt E. , Gleason Karen K. 
Published: April 2008

AbstractThe techniques of initiated chemical vapor deposition (iCVD) and oxidative chemical vapor deposition (oCVD) enable the fabrication of chemically well‐defined thin polymeric films on complex objects with micro‐ and nano‐scale features. By depositing polymers from the vapor phase, many wetting and solution effects are avoided, and conformal films can be created. In iCVD, a variant of hot filament CVD, the deposition rate is enhanced and chemical functionalities of the polymers' constituents are maintained by including a thermally labile initiator in the feed stream. Due to the low energy required when using an initiator, delicate substrates can be coated. In oCVD, infusible, electrically conductive films are formed directly on the substrate of interest as the oxidant and monomer are introduced into the reactor simultaneously. This Feature Article provides an overview of the work that has been done to develop iCVD and oCVD into platform technologies. Relevant background, fundamentals, and applications will be discussed.
β‐ and γ‐Disubstituted Olefins: Substrates for Copper‐Catalyzed Asymmetric Allylic Substitution
Authors: Falciola Caroline A. , Tissot‐Croset Karine , Reyneri Hugo , Alexakis Alexandre 
Published: April 2008

AbstractThe copper‐catalyzed asymmetric allylic alkylation has shown through many examples that it is a powerful means to generate stereogenic centers with mono β‐ and γ‐substituted olefinic substrates. However, little has been reported about more substituted olefinic patterns, such as β‐disubstituted allylic electrophiles. In this paper, we show that a simple procedure using easily accessible Grignard reagents and as low as 3 mol% of copper/ligand can promote high to nearly perfect enantioselectivities (up to >99% ee) with very good γ‐selectivities on a wide panel of aliphatic or aromatic β‐disubstituted substrates.
Population balance modeling of bubbly flows considering the hydrodynamics and thermomechanical processes
Authors: Cheung Sherman C. P. , Yeoh G. H. , Tu J. Y. 
Published: April 2008

AbstractThree‐dimensional two‐fluid model and population balance equation is presented to treat the complex hydrodynamics and thermomechanical processes under various bubbly flow conditions. The class method, realized by the MUSIG model, alongside with suitable bubble coalescence and bubble breakage kernels is adopted. Homogeneous MUSIG model predictions have shown to yield good agreement against isothermal bubbly flow measurements. Subcooled boiling flow is further modeled through the use of class method with an improved wall heat partition model. Against experimental data, numerical results also showed good agreement for the local Sauter mean bubble diameter, void fraction, and interfacial area concentration profiles. Inhomogeneous MUSIG model is applied to investigate transition bubbly‐to‐slug flow. Better prediction of bubble diameter is accomplished, especially capturing separation of small and large bubbles. Weakness exists nonetheless in the interfacial forces model. Work is in progress through the consideration of swarm and cluster bubbles instead of isolated spherical bubble calibration. © 2008 American Institute of Chemical Engineers AIChE J, 2008
PRNP mutations in a series of apparently sporadic neurodegenerative dementias in China
Authors: Zheng Liu , Longfei Jia , Jing Ye , Xinqing Zhang , Haiqing Song , Haiyan Lv , Fen Wang , Xiumin Dong , Jianping Jia 
Published: April 2008

AbstractMutations in prion protein gene (PRNP) may lead to genetic prion disease, which usually has a broad range of phenotypic presentations that overlap with other neurodegenerative dementias. In this study, we screened the PRNP gene to evaluate the frequency of PRNP mutations and their correlations with clinical phenotype in 185 sporadic neurodegenerative dementia cases and 310 control subjects. Samples of DNA from each subject underwent polymerase chain reaction (PCR) amplification and direct sequencing of PRNP. The clinical characteristics of patients carrying PRNP mutations were detailed. We identified five different PRNP mutations in five patients, of which three were novel (S97N, F198V, and R208C) and two were known (D178N‐129M and M232R). The rate of PRNP mutation was 2.70% in our sample. Though future studies confirming the correlation between PRNP mutations and clinical phenotype need to be undertaken, PRNP genotyping may be a valuable tool to differentiate between prion disease and other neurodegenerative dementias. Am. J. Med. Genet. © 2008 Wiley‐Liss, Inc.
Epoxy‐clay nanocomposites: Influence of the clay surface modification on structure
Authors: Rýznarová B. , Zelenka J. , Lednický F. , Baldrian J. 
Published: April 2008

AbstractIn this article, the effect of four different clay surface modifiers on the structure of epoxy‐clay nanocomposites was studied. Various organoclays were prepared via cation exchange reaction between inorganic cations naturally occuring in the clay gallery and different alkylammonium ions. Epoxy‐clay nanocomposites were prepared by in situ intercalative polymerization using a hardener of polyoxypropylenediamine type. It was found that various clay surface modifiers exhibit different catalytic effect on curing of epoxy inside the clay gallery as observed by measuring of the gel time with dynamic mechanical analysis. This was confirmed by monitoring the change in the d‐spacing by wide angle X‐ray scattering performed in situ during curing. Morphology of the cured systems was probed by transmission electron microscopy (TEM) and wide angle X‐ray scattering (WAXS). The degree of dispersion observed by TEM and WAXS corresponds with achieved mechanical properties of cured composites. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Porous honeycomb films prepared from poly (phthalazionone ether sulfone ketone) (PPESK) by self‐organization method
Authors: Zhang Youquan , Tian Ye , Wang Lihua 
Published: April 2008

AbstractPreparation of honeycomb‐patterned films from Poly (phthalazionone ether sulfone ketone) (PPESK), one of the thermally stable polymers, in a humid atmosphere was reported in this article. The mechanism of forming honeycomb structure was discussed. Some influences, such as the effect of PPESK concentration and the atmosphere humidity were tested. Furthermore, the thermal stability of honeycomb‐patterned films was also investigated, and it was shown that the honeycomb structures could be stable existed at 300°C. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Maghnite‐H+, a solid catalyst for the cationic polymerization of α‐methylstyrene
Authors: Moulkheir Ayat , Harrane Amine , Belbachir Mohamed 
Published: April 2008

AbstractThe polymerization of α‐methylstyrene (AMS) catalyzed by Maghnite‐H+(Mag‐H) was investigated. Mag‐H is a montmorillonite sheet silicate clay, exchanged with protons. It was found that the cationic polymerization of AMS is initiated by Mag‐H at ambient temperature in bulk and in solution. The effect of the amount of Mag‐H, the temperature, and the solvent was studied. The polymerization rate increased with increase in the temperature and the proportion of catalyst, and it was larger in nonpolar solvents. These results indicated the cationic nature of the polymerization. It may be suggested that the polymerization is initiated by proton addition to monomer from Mag‐H. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis and characterization of emulsion polymerized mixed matrix aluminum silicate/poly(2,6‐dimethyl 1,4‐phenylene oxide) films
Authors: Sadeghi F. , Tremblay A. Y. , Kruczek B. 
Published: April 2008

AbstractA series of poly (2,6‐dimethyl‐1,4‐phenylene oxide) (PPO)‐based organic/inorganic films for the potential application in membrane gas separation were prepared by employing a method in which aluminum hydroxonitrate contained in a stable water‐in‐oil (W/O) emulsion, the oil phase being a solution of PPO in trichloroethylene, was mixed with a homogeneous solution of PPO in trichloroethylene containing tetraethyl orthosilicate (TEOS). Inorganic polymerization occurred in or at the surface of the aqueous droplets of the W/O emulsion. Subsequently, thin films were prepared by a spin coating technique, and they were referred to as emulsion polymerized mixed matrix (EPMM) films. Scanning electron micrographs taken from a film cross section indicated the presence of particles in the PPO matrix, and energy dispersive X‐ray measurements showed that the embedded particles contained Al and Si elements. Differential scanning calorimetry analysis showed a decrease in the glass transition of the EPMM films with increase of TEOS loading. The compatibility between aluminum silicate nanoparticles and PPO in the EPMM films was confirmed by air separation tests. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Cellular Uptake, Cytotoxicity, and Metabolic Profiling of Human Cancer Cells Treated with Ruthenium(II) Polypyridyl Complexes [Ru(bpy)2(NN)]Cl2 with NN=bpy, phen, dpq, dppz, and dppn
Authors: Schatzschneider Ulrich , Niesel Johanna , Ott Ingo , Gust Ronald , Alborzinia Hamed , Wölfl Stefan 
Published: April 2008

AbstractA series of five ruthenium(II) polypyridyl complexes [Ru(bpy)2(NN)]Cl2 was tested against human HT‐29 and MCF‐7 cancer cell lines. Cellular uptake efficiency and cytotoxicity were found to increase with the size of the aromatic surface area of the NN ligand. The most active compound carrying the dppn ligand exhibits a low micromolar IC50 value against both cell lines comparable to that of cisplatin under similar conditions. Continuous measurement of oxygen consumption, extracellular acidification rate, and impedance of the cell layer with a chip‐based sensor system upon exposure to the complexes showed only small changes for the first two parameters throughout the series. A significant and irreversible decrease in impedance was, however, found for the dppn compound. This suggests that its biological activity is related to modifications in cell morphology or cell–cell and cell–matrix contacts.
Structural remodeling of nucleus ambiguus projections to cardiac ganglia following chronic intermittent hypoxia in C57BL/6J mice
Authors: Lin Min , Ai Jing , Li Lihua , Huang Chenghui , Chapleau Mark W. , Liu Rugao , Gozal David , Wead William B. , Wurster Robert D. , Cheng Zixi (Jack) 
Published: April 2008

AbstractThe baroreflex control of heart rate (HR) is reduced following chronic intermittent hypoxia (CIH). Since the nucleus ambiguus (NA) plays a key role in baroreflex control of HR, we examined whether CIH remodels vagal efferent projections to cardiac ganglia. C57BL/6J mice (3–4 months of age) were exposed to either room air (RA) or CIH for 3 months. Confocal microscopy was used to examine NA axons and terminals in cardiac ganglia following Fluoro‐Gold (FG) injections to label cardiac ganglia, and microinjections of tracer DiI into the left NA to anterogradely label vagal efferents. We found that: 1) Cardiac ganglia were widely distributed on the dorsal surface of the atria. Although the total number of cardiac ganglia did not differ between RA and CIH mice, the size of ganglia and the somatic area of cardiac principal neurons (PNs) were significantly decreased (P < 0.01), and the size of the PN nuclei was increased following CIH (P < 0.01). 2) NA axons entered cardiac ganglia and innervated PNs with dense basket endings in both RA and CIH mice, and the percentage of innervated PNs was similar (RA: 50 ± 1.0%; CIH: 49 ± 1.0%; P > 0.10). In CIH mice, however, swollen cardiac axons and terminals without close contacts to PNs were found. Furthermore, varicose endings around PNs appeared swollen and the axonal varicose area around PNs was almost doubled in size (CIH: 163.1 ± 6.4 μm2; RA: 88 ± 3.9 μm2, P < 0.01). Thus, CIH significantly altered the structure of cardiac ganglia and resulted in reorganized vagal efferent projections to cardiac ganglia. Such remodeling of cardiac ganglia and vagal efferent projections provides new insight into the effects of CIH on the brain–heart circuitry of C57BL/6J mice. J. Comp. Neurol. 509:103–117, 2008. © 2008 Wiley‐Liss, Inc.