bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of nanofibrous morphology in LDPE/LLDPE/PP blends and its effect on mechanical properties of blend films
Authors: Sonawane Pradip S. , Radhakrishnan S. , Bhangale J. A. , Gadhavi A. L. , Khare Anagha 
Published: December 2007

AbstractNanofibrous morphology has been observed in ternary blends of low density polyethylene (LDPE), linear low density polyethylene (LLDPE), and isotactic polypropylene (PP) when these were melt‐extruded via slit die followed by hot stretching. The morphology was dependent on the concentration of the component polymers in ternary blend LDPE/LLDPE/PP. The films were characterized by wide angle X‐ray diffraction (XRD), scanning electron microscopy (SEM), and testing of mechanical properties. The XRD patterns reveal that the β phase of PP is obtained in the as‐stretched nanofibrillar composites, whose concentration decreases with the increase of LLDPE concentration. The presence of PP nanofibrils shows significant nucleation ability for crystallization of LDPE/LLDPE blend. The SEM observations of etched samples show an isotropic blend of LDPE and LLDPE reinforced with more or less randomly distributed and well‐defined nanofibrils of PP, which were generated in situ. The tensile modulus and strength of LDPE/LLDPE/PP blends were significantly enhanced in the machine direction than in the transverse direction with increasing LLDPE concentration. The ultimate elongation increased with increasing LLDPE concentration, and there was a critical LLDPE concentration above which it increased considerably. There was a dramatic increase in the falling dart impact strength for films obtained by blow extrusion of these blends. These impressive mechanical properties of extruded samples can be explained on the basis of the formation of PP nanofibrils with high aspect ratio (at least 10), which imparted reinforcement to the LDPE/LLDPE blend. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Monodisperse Magnetite Nanoparticles Coupled with Nuclear Localization Signal Peptide for Cell‐Nucleus Targeting
Authors: Xu Chenjie , Xie Jin , Kohler Nathan , Walsh Edward G. , Chin Y. Eugene , Sun Shouheng 
Published: December 2007

AbstractFunctionalization of monodisperse superparamagnetic magnetite (Fe3O4) nanoparticles for cell specific targeting is crucial for cancer diagnostics and therapeutics. Targeted magnetic nanoparticles can be used to enhance the tissue contrast in magnetic resonance imaging (MRI), to improve the efficiency in anticancer drug delivery, and to eliminate tumor cells by magnetic fluid hyperthermia. Herein we report the nucleus‐targeting Fe3O4 nanoparticles functionalized with protein and nuclear localization signal (NLS) peptide. These NLS‐coated nanoparticles were introduced into the HeLa cell cytoplasm and nucleus, where the particles were monodispersed and non‐aggregated. The success of labeling was examined and identified by fluorescence microscopy and MRI. The work demonstrates that monodisperse magnetic nanoparticles can be readily functionalized and stabilized for potential diagnostic and therapeutic applications.
GDNF fusion protein for targeted‐drug delivery across the human blood–brain barrier
Authors: Boado Ruben J. , Zhang Yun , Zhang Yufeng , Wang Yuntao , Pardridge William M. 
Published: December 2007

AbstractGlial‐derived neurotrophic factor (GDNF) is a neurotrophin that could be developed as a neurotherapeutic for Parkinson's disease, stroke, and motor neuron disease. However, GDNF does not cross the blood–brain barrier (BBB). Human GDNF was re‐engineered by fusion of the mature GDNF protein to the carboxyl terminus of the chimeric monoclonal antibody (MAb) to the human insulin receptor (HIR). The HIRMAb‐GDNF fusion protein is bi‐functional, and both binds the HIR, to trigger receptor‐mediated transport across the BBB, and binds the GDNF receptor (GFR)‐α1, to activate GDNF neuroprotection pathways behind the BBB. COS cells were dual transfected with the heavy chain (HC) and light chain fusion protein expression plasmids, and the HC of the fusion protein was immunoreactive with antibodies to both human IgG and GDNF. The HIRMAb‐GDNF fusion protein bound with high affinity to the extracellular domain of both the HIR, ED50 = 0.87 ± 0.13 nM, and the GFRα1, ED50 = 1.68 ± 0.17 nM. The HIRMAb‐GDNF fusion protein activated luciferase gene expression in human neural SK‐N‐MC cells dual transfected with the c‐ret kinase and a luciferase reporter gene under the influence of the rat tyrosine hydroxylase promoter, and the ED50, 1.68 ± 0.45 nM, was identical to the ED50 in the GFRα1 binding assay. The fusion protein was active in vivo in a rat middle cerebral artery occlusion model, where the stroke volume was reduced 77% (P < 0.001). In conclusion, these studies describe the re‐engineering of GDNF, to make this neurotrophin transportable across the human BBB. Biotechnol. Bioeng. 2008;100: 387–396. © 2007 Wiley Periodicals, Inc.
Predicting first molar width using virtual models of dental arches
Authors: Lee Seung‐Pyo , Delong Ralph , Hodges James S. , Hayashi Kazuo , Lee Jae‐Bong 
Published: December 2007

AbstractIn dentistry, large regions of dentition often are restored with minimal information about the original anatomy. The ability to predict missing anatomy from existing anatomy would aid such restorations. This study investigated the relationship between first molar mesial‐distal width and arch shape using newly defined reference points and three‐dimensional (3D) digital methods. Full‐mouth dental stone casts from 167 dental students were scanned and rendered as 3D virtual models. Maxillary and mandibular arch lengths and widths and first molar mesial‐distal widths were measured on the virtual models using new definitions incorporating virtual planes. A linear mixed model of the first molar width regressed on the other measurements was done. Intraobserver reproducibility was evaluated by means of intraclass correlation (ICC) and standard deviation of measurement error (SDME). All measured distances were averaged as a combined group and as gender groups. The correlation coefficients between the maxillary and mandibular first molar widths were over 0.70 (P < 0.01). Intraobserver error was small. ICCs were over 0.92 and SDMEs were from 0.11 to 0.21 mm. Arch dimensions and first molar widths were defined and measured. Regression equations were calculated for predicting first molar width. The prediction of first molar width using arch dimension is essential for virtual designing of missing first molars. This approach also provides reliable reference point definitions for the virtual dental model which was impossible with traditional measurement methods. Therefore, this study would be helpful for understanding the 3D anatomy of dental arch and fabrication of automatic prosthodontic restorations. Clin. Anat. 21:27–32, 2008. © 2007 Wiley‐Liss, Inc.
Synthesis, Molecular Structure and Properties of the [H6−nNi30C4(CO)34(CdCl)2]n− (n=3–6) Bimetallic Carbide Carbonyl Cluster: A Model for the Growth of Noncompact Interstitial Metal Carbides
Authors: Bernardi Alessandro , Femoni Cristina , Iapalucci Maria Carmela , Longoni Giuliano , Ranuzzi Fabrizio , Zacchini Stefano , Zanello Piero , Fedi Serena 
Published: December 2007

AbstractReaction of the [Ni9C(CO)17]2− dianion with CdCl2⋅2.5 H2O in THF affords the novel bimetallic NiCd carbide carbonyl clusters [H6−nNi30C4(CO)34(μ5‐CdCl)2]n− (n=3–6), which undergo several protonation–deprotonation equilibria in solution depending on the basicity of the solvent or upon addition of acids or bases. Although the occurrence in solution of these equilibria complicates the pertinent electrochemical studies on their electron‐transfer activity, they clearly indicate that the clusters [H6−nNi30C4(CO)34(μ5‐CdCl)2]n− (n=3–6), as well as the structurally related [H6−nNi34C4(CO)38]n− (n=4–6), undergo reversible or partially reversible redox processes and provide circumstantial and unambiguous evidence for the presence of hydrides for n=3, 4 and 5. Three of the [H6−nNi30C4(CO)34(μ5‐CdCl)2]n− anions (n=4–6) have been structurally characterized in their [NMe3(CH2Ph)]4[H2Ni30C4(CO)34(CdCl)2]⋅2 COMe2, [NEt4]5[HNi30C4(CO)34(CdCl)2]⋅2 MeCN and [NMe4]6[Ni30C4(CO)34(CdCl)2]⋅6 MeCN salts, respectively. All three anions display almost identical geometries and bonding parameters, probably because charge effects are minimized by delocalization over such a large metal carbonyl anion. Moreover, the Ni30C4 core in these NiCd carbide clusters is identical within experimental error to those present in the [HNi34C4(CO)38]5− and [Ni35C4(CO)39]6− species, suggesting that the stepwise assembly of their nickel carbide cores may represent a general pathway of growth of nickel polycarbide clusters. The fact that the [H6−nNi30C4(CO)34(μ5‐CdCl)2]n−(n=4–6) anions display two valence electrons more than the structurally related [H6−nNi34C4(CO)38]n− (n=4–6) species has been rationalized by extended Hückel molecular orbital (EHMO) analysis.
Modeling Carbon and Nitrogen Removal in an Industrial Wastewater Treatment Plant Using an Adaptive Network‐Based Fuzzy Inference System
Authors: Civelekoglu Gokhan , Perendeci Altunay , Yigit Nevzat O. , Kitis Mehmet 
Published: December 2007

AbstractAdvanced neuro‐fuzzy modeling, namely an adaptive network‐based fuzzy inference system (ANFIS), was employed to develop models for the prediction of carbon and nitrogen removal in the aerobic biological treatment stage of a full‐scale wastewater treatment plant treating process wastewaters from the sugar production industry. A total of six independent ANFIS models were developed with or without principal component analysis (PCA) using the correlations among the influent and effluent data from the plant. Input variables were reduced from eight to four and from eleven to nine for chemical oxygen demand (COD) and NH4+–N–TN (total nitrogen) models, respectively, by considering PCA results and linear correlation matrices among input and output variables. Correlation coefficients (R) were not in good agreement with root mean square error (RMSE) and average percentage error (APE) values without PCA. For the COD model after PCA; RMSE, APE and R values were 9.4 mg/L, 8.37 and 0.978%, respectively. Such values for the TN model were 4.3 mg/L, 23.65 and 0.992%. The results overall indicated that the simulated effluent COD, NH4+–N, and TN concentrations well fit measured concentrations. The ANFIS modeling approach may have application potential for performance prediction and control of treatment processes in treatment plants.
Model Based Evaluation for the Anaerobic Treatment of Corn Processing Wastewaters
Authors: Ersahin Mustafa Evren , Insel Guclu , Dereli Recep Kaan , Ozturk Izzet , Kinaci Cumali 
Published: December 2007

AbstractThe objective of this study was to implement a process model to simulate the dynamic behavior of a full‐scale anaerobic reactor treating corn processing wastewaters under mesophilic conditions. For this purpose, the IWA Anaerobic Digestion Model No.1 (ADM1) was applied to an expanded granular sludge bed reactor of an industrial wastewater treatment plant. The plant has a wastewater treatment capacity of 1594 m3/day. Sensitivity analysis showed that the influent characterization, based on disintegration into carbohydrates, proteins, lipids and inert components, had a large impact on the model outputs. An efficient correlation obtained between the measured and the simulated data, including effluent COD, pH and methane production, highlights good parameter optimization and wastewater characterization. This paper demonstrates a practical example for the application of the ADM1 to an agro‐industrial full‐scale anaerobic reactor.
Local self‐assembly mechanisms underlie the differential transformation of the proximal and distal cut axonal ends into functional and aberrant growth cones
Authors: Erez Hadas , Spira Micha E. 
Published: December 2007

AbstractFollowing axotomy, both the proximal and distal cut axonal ends transform into growth cones (GCs). Whereas the GCs formed by the tip of the proximal segment branch to form neurites, the structure formed by the distal cut end fails to grow. The mechanisms underlying the formation of an aberrant GC by the distal cut end are not understood. Earlier we described the cascade that transforms the tip of the proximal cut axon into a GC. This involves microtubule (MT) polar reorientation, which culminates in the formation of two MT‐based vesicle traps, one for Golgi‐derived vesicles and the other that retains retrogradely transported vesicles. The formation of these traps is the outcome of local interactions between dynamically repolymerizing MTs and molecular motors. The concentration of Golgi‐derived vesicles in the plus‐end trap is essential for the successful generation of a functional GC. By using online confocal imaging of transected culturedAplysianeurons, we analyzed here the restructuring of the distal cut end after axotomy. We found that initially the proximal and distal cut ends undergo identical alterations. Nevertheless, in contrast to the proximal end, the distal cut axon forms only a minus‐end MT‐based trap that concentrates endocytotic vesicles driven by minus‐end oriented motors. Whereas the MTs forming the trap polymerize pointing their plus‐ends centrifugally to form finger‐like protrusions, the trapped vesicles cannot translocate out to fuse with the plasma membrane. Thus, the structure formed at the distal cut axon is incompetent to support growth processes. J. Comp. Neurol. 507:1019–1030, 2008. © 2007 Wiley‐Liss, Inc.
Transmission Holographic Polymer Dispersed Liquid Crystals Based on a Siloxane Polymer
Authors: Woo Ju Yeon , Kim Eun Hee , Kim Byung Kyu 
Published: December 2007

AbstractThe low surface energy and the great immiscibility of poly (dimethylsiloxane) (PDMS) with liquid crystals (LCs) are used in the fabrication of holographic polymer dispersed liquid crystals (HPDLCs). By adding increasing amounts of PDMS, the extent of the phase separation between the polymer and the LC, the LC channel width, and—eventually—also the diffraction efficiency of the film can be increased, while keeping the droplet size essentially the same. In addition, the presence of PDMS causes a decrease in the switching voltage and an increase in the response time. At an optimum content of PDMS (PUA40), a minimum switching voltage of 4 V μm−1, a rise time of 0.20 ms, and a decay of 14.75 ms were obtained. Regarding the effect of the LC content, an overshoot of the diffraction efficiency was observed when the amount of LC exceeded 35 %, which can be attributed to droplet coalescence.
Peripheral sensitization in migraine—role for P2X purinergic receptors in the dura–vascular sensory pathway
Authors: Jennings Ernest A. , Cho Hyun‐jung 
Published: December 2007

AbstractPeripheral sensitization is still considered a prime contributor underlying the mechanisms of migraine. Trigeminal primary afferent neurons are the first neurons in the dural nociceptive pathway, and activation results in conscious perception of pain. Peripheral sensitization can lower the activation threshold of primary afferent neurons, rendering them more excitable, allowing for increases in release of neurotransmitter from both central and peripheral terminals. Increase in neurotransmitter release from central terminals contributes to excitation of second‐order neurons, while the release of peptides from peripheral terminals has been implicated in neurogenic inflammation. Adenosine 5′‐triphosphate (ATP) causes pain in human studies, and depolarize sensory neurons. There is evidence of the action of ATP at many levels in the dura–vascular sensory pathway. Animal studies have shown that some P2X receptors are located in neurons innervating the dura, including the P2X3 receptor, which is most often shown to be involved in nociceptive pathways. In this article, we briefly review peripheral sensitization in relation to migraine and provide emphasis for P2X receptor involvement where it is available. Drug Dev Res 68:321–328, 2007. © 2007 Wiley‐Liss, Inc.
Solid‐State Au/Hg Microelectrode for the Investigation of Fe and Mn Cycling in a Freshwater Wetland: Implications for Methane Production
Authors: Ma Shufen , Luther George W. , Keller Jason , Madison Andrew S. , Metzger Edouard , Emerson David , Megonigal J. Patrick 
Published: December 2007

AbstractThe solid‐state voltammetric gold‐amalgam microelectrode was used to measure multiple redox species (O, S, Fe and Mn) in situ at (sub)millimeter vertical resolution to elucidate rhizosphere processes in Jug Bay wetlands. In vegetated soil, a classic diagenetic redox sequence without any dissolved sulfide was observed in summer. However, the rhizosphere can be quite variable which is due to the introduction of O2 to the anoxic sediments by plants. In nonvegetated soil, the vertical concentration–depth profiles were relatively constant. The presence of Fe(II), Mn(II) and soluble Fe(III) in deeper sediments indicates the oxidation of Fe(II) as well as the nonreductive dissolution of Fe(III) and the reductive dissolution of Fe(III) and Mn(III, IV) solids. Mn(III, IV) and Fe(III) redox chemistry is important in organic matter mineralization mediated by bacteria and in suppressing methane formation. In addition, Mn(III, IV) also can oxidize Fe(II) to supply Fe(III) for bacterial Fe(III) reduction. Studying Fe and Mn cycling via voltammetric methods can give insights to methane production and loss as there is no methane sensor for sediment work at present.
Gel‐Integrated Voltammetric Microsensors and Submersible Probes as Reliable Tools for Environmental Trace Metal Analysis and Speciation
Authors: Tercier‐Waeber Mary‐Lou , Confalonieri Fabio , Koudelka‐Hep Milena , Dessureault‐Rompré Jacynthe , Graziottin Flavio , Buffle Jacques 
Published: December 2007

AbstractThis article gives a review of the analytical and environmental criteria which must be considered and the relevant specific developments needed for direct, reliable voltammetric measurements of trace metal speciation in environmental systems. In particular, this article will focus on the tools which enable remote, long‐term in situ measurements. The development of such tools is a challenging task. The strategies that can be used to achieve this goal are described for the development of innovative and versatile gel‐integrated voltammetric microsensors, micro‐/mini‐integrated analytical systems, and submersible probes. The advantages of these new tools with respect to selectivity, sensitivity, reliability, spatial and temporal resolution of data, and thus efficient environmental monitoring of the biogeochemical cycle of trace metals are demonstrated by providing examples of measurements made in various aquatic samples in laboratory (water, soils, solid–liquid interface) and in situ in fresh and seawaters.
Evaluation of Liquid‐ and Solid‐Contact, Pb2+‐Selective Polymer‐Membrane Electrodes for Soil Analysis
Authors: McGraw Christina M. , Radu Tanja , Radu Aleksandar , Diamond Dermot 
Published: December 2007

AbstractPb2+‐selective electrodes (ISEs) have been developed for the analysis of soil. Recent advances have extended the previous achievable limits of detection of ion‐selective electrodes (ISEs) to submicromolar levels, opening up possibilities for new applications in environmental analysis. The simple construction of ISE's, their low cost and low power demand, coupled with improved detection limits make the electrodes well suited for environmental analysis. In this paper, the development and use of both liquid‐ and solid‐contact ISEs for the detection of Pb2+ in a range of soil samples from abandoned mining sites is described. Solid‐contact electrodes were made using poly(3‐octylthipophene) as the internal mixed conductor layer. In addition, three techniques for the extraction of analyte from soil were studied in order to optimize the extraction of metal ions using techniques and solvents compatible with portable devices. Soil Pb2+ levels between 30 and 29,100 mg/kg were measured with the ISEs and were shown to be in good agreement with reference AAS measurements. Issues arising from the current definition and interpretation of ISE detection limits are also discussed.
A New Enzyme Immobilization Technique Based on Thionine‐Bovine Serum Albumin Conjugate and Gold Colloidal Nanoparticles for Reagentless Amperometric Biosensor Applications
Authors: Chen Shihong , Yuan Ruo , Chai Yaqin , Li Na 
Published: December 2007

AbstractA novel enzyme immobilization technique based on thionine‐bovine serum albumin conjugate (Th‐BSA) and gold colloidal nanoparticles (nano‐Au) was developed. Thionine was covalently bound onto the BSA film with glutaraldehyde(GA) as cross‐linker to achieve Th‐BSA conjugate. The free amino groups of thionine were then used to attach nano‐Au for the immobilization of horseradish peroxidase (HRP). Such nano‐Au/Th‐BSA matrix shows a favorable microenvironment for retaining the native activity of the immobilized HRP and thionine immobilized in this way can effectively shuttle electrons between the electrode and the enzyme. The proposed biosensor displays excellent catalytic activity and rapid response for H2O2. The linear range for the determination of H2O2 is from 4.9×10−7 to 1.6×10−3 M with a detection limit of 2.1×10−7 M at 3σ and a Michaelies‐Menten constant K$\rm{ {_{M}^{app}}}$ value of 0.023 mM.
CE hydrogen deuterium exchange‐MS in peptide analysis
Authors: Lau Simon S. M. , Stainforth Nick M. , Watson David G. , Skellern Graham G. , Wren Stephen A. C , Tettey Justice N. A. 
Published: December 2007

AbstractCE and hydrogen‐deuterium (H/D) exchange MS are useful tools in the analysis and characterisation of peptides. This study reports the facile coupling of these tools in the H/D exchange CE‐MS analysis of model and pharmaceutically important peptides, using a sheath flow interface. The peptides varied in mass from 556 (leucine enkephalin) to 1620 Da (bombesin), and in charge state from 0.33 (leucine enkephalin) to 3.0 (substance P). The application of a BGE composed of ammonium formate buffer (25 mM, pD 3.5 in D2O (>98% D atom)), a sheath liquid composed of formic acid (0.25% v/v in D2O) and ACN (30:70 v/v), and dissolving the samples in a mixture of ACN/D2O (50:50 v/v) facilitates complete H/D exchange. Because of complete H/D exchange the ESI mass spectra produced are easy to interpret and comparable to those obtained from LC‐MS analysis. The CE‐H/D‐MS approach has the advantage of requiring lower volumes of deuterated solvents. The b‐ and y‐series fragments produced by using in‐source decomposition correspond to those predicted. With the peptides studied, the complete exchange H/D exchange observed with both the molecular and fragment ions helps to confirm both amino acid composition and sequence.
CE of poly(amidoamine) succinamic acid dendrimers using a poly(vinyl alcohol)‐coated capillary
Authors: Desai Ankur , Shi Xiangyang , Baker James R. 
Published: December 2007

AbstractVarious generations (G1–G8) of negatively charged poly(amidoamine) (PAMAM) succinamic acid dendrimers (PAMAM‐SAH) were analyzed by CE using a poly(vinyl alcohol)‐coated capillary. Due to its excellent stability and osmotic flow‐shielding effect, highly reproducible migration times were achieved for all generations of dendrimer (e.g., RSD for the migration times of G5 dendrimer was 0.6%). We also observed a reverse trend in migration times for the PAMAM‐SAH dendrimers (i.e., higher generations migrated faster than lower generation dendrimers) compared to amine‐terminated PAMAM dendrimers reported in the literature. This reversal in migration times was attributed to the difference in counterion binding around these negatively charged dendrimers. This reverse trend allowed a generational separation for lower generation (G1–G3) dendrimers. However, a sufficient resolution for the migration peaks of higher generations (G4–G5) in a mixture could not be achieved. This could be due to their nearly identical charge/mass ratio and dense molecular conformations. In addition, we show that dye‐functionalized PAMAM‐SAH dendrimers can also be analyzed with high reproducibility using this method.