bluuebunny/crossref_metadata_2025_split huggingface dataset:
Performance of delay‐sensitive traffic in multi‐layered satellite IP networks with on‐board processing capability
Authors: Bayhan Suzan , Gür Gürkan , Alagöz Fatih 
Published: February 2007

AbstractIn this article, performance of delay‐sensitive traffic in multi‐layered satellite Internet Protocol (IP) networks with on‐board processing (OBP) capability is investigated. With OBP, a satellite can process the received data, and according to the nature of application, it can decide on the transmission properties. First, we present a concise overview of relevant aspects of satellite networks to delay‐sensitive traffic and routing. Then, in order to improve the system performance for delay‐sensitive traffic, specifically Voice over Internet Protocol (VoIP), a novel adaptive routing mechanism in two‐layered satellite network considering the network's real‐time information is introduced and evaluated. Adaptive Routing Protocol for Quality of Service (ARPQ) utilizes OBP and avoids congestion by distributing traffic load between medium‐Earth orbit and low‐Earth orbit layers. We utilize a prioritized queueing policy to satisfy quality‐of‐service (QoS) requirements of delay‐sensitive applications while evading non‐real‐time traffic suffer low performance level. The simulation results verify that multi‐layered satellite networks with OBP capabilities and QoS mechanisms are essential for feasibility of packet‐based high‐quality delay‐sensitive services which are expected to be the vital components of next‐generation communications networks. Copyright © 2007 John Wiley & Sons, Ltd.
Targeting HSP70 to motoneurons protects locomotor activity from hyperthermia in Drosophila
Authors: Xiao Chengfeng , Mileva‐Seitz Viara , Seroude Laurent , Robertson R. Meldrum 
Published: February 2007

AbstractHeat shock preconditioning can enhance locomotor and synaptic performance during subsequent hyperthermia. The molecular basis underlying this neural phenotypic modification is largely unknown. Here we report that directing the expression of the 70 kDa heat shock protein (HSP70) to motoneurons protected larval locomotor activity of Drosophila. Tissue‐specific expression showed that motoneurons were critical for developing HSP70‐mediated thermoprotection of locomotor activity, whereas peripheral sensory neurons, dopaminergic neurons, serotonergic neurons, and muscle cells alone were insufficient. Targeting HSP70 to motoneurons caused structural plasticity of axonal terminals associated with increased transmitter release at neuromuscular junctions at high temperature. The thermoprotection induced by motoneuronal expression of HSP70 mimicked the protective effect of a prior heat shock (36°C, 1 h; 25°C, 1 h) but the effects of heat shock and motoneuronal expression of HSP70 were not additive. In the absence of heat shock pretreatment, ubiquitously expressed transgenic HSP70 activated the transcription of endogenous hsp70 genes. These results demonstrate that motoneurons were critical for HSP70‐mediated thermoprotection, and that transgenic HSP70 activated the transcription of endogenous hsp70 in motoneurons with the result that a mix of transgenic and endogenous HSP70 conferred thermoprotection in Drosophila larva. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007
Effects of progesterone and its reduced metabolites, dihydroprogesterone and tetrahydroprogesterone, on the expression and phosphorylation of glycogen synthase kinase‐3 and the microtubule‐associated protein Tau in the rat cerebellum
Authors: Guerra‐Araiza Christian , Amorim Miguel A.R. , Camacho‐Arroyo Ignacio , Garcia‐Segura Luis M. 
Published: February 2007

AbstractProgesterone exerts a variety of actions in the brain, where it is rapidly metabolized to 5α‐dihydroprogesterone (DHP) and 3α,5α‐tetrahydroprogesterone (THP). The effect of progesterone and its metabolites on the expression and phosphorylation of the microtubule‐associated protein Tau and glycogen synthase kinase 3β (GSK3β), a kinase involved in Tau phosphorylation, were assessed in two progesterone‐sensitive brain areas: the hypothalamus and the cerebellum. Administration of progesterone, DHP, and THP to ovariectomized rats did not affect Tau and GSK3β assessed in whole hypothalamic homogenates. In contrast, progesterone and its metabolites resulted in a significant decrease in the expression of Tau and GSK3β in the cerebellum. Furthermore, progesterone administration resulted in an increase in the phosphorylation of two epitopes of Tau (Tau‐1 and PHF‐1) phosphorylated by GSK3β, but did not affect the phosphorylation of an epitope of Tau (Ser262) that is GSK3β insensitive. These effects were accompanied by a decrease in the phosphorylation of GSK3β in serine, which is associated to an increase in its activity, suggesting that the effect of progesterone on Tau‐1 and PHF‐1 phosphorylation in the cerebellum is mediated by GSK3β. The regulation of Tau expression and phosphorylation by progesterone may contribute to the hormonal regulation of cerebellar function by the modification of neuronal cytoskeleton. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007
Microtubule‐dependent organization of subcortical microfilaments in the early Drosophila embryo
Authors: Riparbelli Maria Giovanna , Callaini Giuliano , Schejter Eyal D. 
Published: February 2007

AbstractDynamic alterations in the spatial organization of cytoskeletal elements constitute a prominent morphological feature of the early, syncytial stages of embryogenesis in Drosophila. Here, we describe and characterize the dynamic behavior of cytoplasmic, subcortical microfilaments, which form a series of nucleus‐associated structures, at different phases of the simultaneous nuclear division cycles characteristic of early Drosophila embryos. Remodeling of the cytoplasmic microfilament arrays takes place in parallel to the established cyclic reorganization of cortical microfilament structures. We provide evidence that the cortical and subcortical microfilament populations organize independently of each other, and in response to distinct instructive cues. Specifically, formation of subcortical microfilament structures appears to rely on, and spatially mirror, the organization of polarized microtubule arrays, while cortical microfilament restructuring constitutes a centrosome‐dependent process. Genetic analysis identifies a requirement for SCAR, a key mediator of Arp2/3‐based microfilament dynamics, in organization of subcortical microfilament structures. Developmental Dynamics 236:662–670, 2007. © 2007 Wiley‐Liss, Inc.
Synthesis of Controllable‐Size Core–Shell Se@Ag and Se@Au Nanoparticles in UV‐Irradiated TSA Solution
Authors: Yang Liangbao , Shen Yuhua , Xie Anjian , Liang Jianjun , Zhu Jinmiao , Chen Long 
Published: February 2007

AbstractThe formation of Se‐core–Au‐shell and Se‐core–Ag‐shell nanoparticles by using photochemically reduced tungstosilicate Keggin ions has been described. The Se core structure serves both as a chemical and a physical template for the coating of Au and Ag. With this method, the core size and the shell thickness can be controlled by varying the conditions. With this strategy, it is possible to realize a large combination of core–shell nanostructures with potential application in engineered nanomaterials and catalysis by using Keggin ions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Carbon–Hydrogen Bond Activation of Arenes by a [Bis(oxazolinyl)phenyl]rhodium(III) Acetate Complex
Authors: Ito Jun‐ichi , Nishiyama Hisao 
Published: February 2007

AbstractThermolysis of the rhodium(III) complex [(dm‐Phebox‐dm)Rh(OAc)2(H2O)] [1; dm‐Phebox‐dm = 2,6‐bis(4,4‐dimethyloxazolinyl)phenyl] in various arenes results in the formation of the corresponding aryl complexes [(dm‐Phebox‐dm)Rh(Ar)(κ2‐OAc)] [Ar = C6H5 (2), 3,5‐Me2C6H3 (3), 3,4‐Me2C6H3 (4), C6H4Me (5), C6H4CF3 (6), C6H4OMe (7), C6H4COMe (8), C6H4Cl (9)]. The reaction of 1 with monosubstituted benzenes such as toluene, anisole, acetophenone, trifluorotoluene, and chlorobenzene produces a mixture of meta‐ and para‐activated complexes, the ratio of which depends on the substituents on the benzene ring. The relative rate of the reaction of 1 with monosubstituted benzenes C6H5X was determined to be: X = OMe (1.8) > COMe (1.6) > CF3 (1.2), Cl (1.2) > CH3 (1). The acetato ligand of 1 appears to be essential for C–H bond activation of arenes as no reaction of the RhIII complex [(dm‐Phebox‐dm)RhCl2(H2O)] is observed in chlorobenzene at 120 °C. The first‐order rate constants obtained by thermolysis of 1 in [D8]toluene at 97.1–116.5 °C yielded the following activation parameters: ΔH‡ = 22(2) kcal mol–1, ΔS‡ = –24(5) cal mol–1 K–1. The kinetic isotope effect for the C–H bond activation of toluene by 1 was determined to be kH/kD = 5.4 at 100 °C. These data suggest that the rate‐determining step involves the C–H bond cleavage with a rigid, cyclic transition structure. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
A Novel Class of Modified Nucleosides: Synthesis of Alkylidene Isoxazolidinyl Nucleosides Containing Thymine
Authors: Piperno Anna , Rescifina Antonio , Corsaro Antonino , Chiacchio Maria A. , Procopio Antonio , Romeo Roberto 
Published: February 2007

AbstractThe synthesis of hitherto unknown 1‐[3‐(hydroxymethyl)‐2‐methyl‐4‐methyleneisoxazolidin‐5‐yl]thymine (5), 1‐{(Z)‐[3‐(hydroxymethyl)‐2‐methylisoxazolidin‐4‐ylidene]methyl}thymine (6), and 1‐{(E)‐[3‐(hydroxymethyl)‐2‐methylisoxazolidin‐5‐ylidene]methyl}thymine (7) is described. The first compound can be regarded as a N,O‐analogue of Entecavir and DMDC, which contains thymine as a nucleobase. The key allenic nucleobase was prepared in good yields starting from 2,3‐dibromopropene. The subsequent 1,3‐dipolar cycloaddition proceeded with good site selectivity to give 5 and regioisomeric nucleosides 6 and 7.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Regio‐ and Diastereoselective Three‐Component Syntheses of Homoallylic Amines in Aqueous Media Catalyzed by Brønsted Acids
Authors: Deng Dong‐Sheng , Liu Ping , Cai Jiwen 
Published: February 2007

AbstractA systematic investigation into the three component allylation reaction of aldehydes, amines, and allyltributylstannanes catalyzed by Brønsted acids in aqueous media was reported. The reaction was effective and able to produce homoallylic amines in moderate to high yields under mild conditions, with a good scope of substrates. Moreover, the regioselectivity of the reaction favors the formation of the γ‐product, and good diastereoselectivity in favor of the syn isomers when cinnamyltributylstannane was employed as the allylation reagent was observed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Amperometric Biosensors for Detection of Sugars Based on the Electrical Wiring of Different Pyranose Oxidases and Pyranose Dehydrogenases with Osmium Redox Polymer on Graphite Electrodes
Authors: Tasca Federico , Timur Suna , Ludwig Roland , Haltrich Dietmar , Volc Jindrich , Antiochia Riccarda , Gorton Lo 
Published: February 2007

AbstractElectrical wiring of different types of pyranose oxidase (P2O) (fungal wild type, recombinant wild type with a hexa‐histidine tag, mutant form E542K with a hexa‐histidine tag) from Trametes multicolor, and recombinant P2O from Coriolus sp. overexpressed in Escherichia coli as well as of pyranose dehydrogenase (PDH) from Agaricus meleagris and Agaricus xanthoderma with an osmium redox polymer (poly(1‐vinylimidazole)12‐[Os(4,4′‐dimethyl‐2,2′‐dipyridyl)2Cl2]2+/+) on graphite electrodes was carried out. After optimization studies using glucose as substrate, the biosensors, which showed the best characteristics in terms of linear range, detection limit and sensitivity were selected, viz. wild type P2O from T. multicolor and PDH from A. meleagris. These two enzymes were used and investigated for their selectivity for a number of different sugars.
Electrochemical response and separation in cyclic electric field‐flow fractionation
Authors: Chen Zhi , Chauhan Anuj 
Published: February 2007

AbstractElectric field‐flow fractionation (EFFF) is a separation technique that couples a lateral electric field with axial Poiseuille flow to separate particles on the basis of size and/or mobility. In unidirectional EFFF, the field rapidly decreases in time due to charging of the double layer. The field strength could be increased by performing EFFF with cyclic electric fields. In cyclic electric field‐flow fractionation (CEFFF), a periodic voltage, which can be either sinusoidal or square‐wave, is applied in the lateral direction. In this paper, we measure the electrochemical response of CEFFF, i.e., the current–time response for a given time‐dependent voltage and then utilize this electrochemical response in a transport model to predict separation. The CEFFF device studied here comprises two gold‐coated glass plates separated by a spacer. The transient current profiles are measured for a step change and cyclic square‐shaped voltage. The current profile is compared with the equivalent circuit model, and is fitted to a sum of two decaying exponentials. The dependence of the electrochemical response on voltage, frequency, channel thickness, and salt concentration is studied. Next, the electrochemical data are utilized in the convection–diffusion equation to develop a model for separation by CEFFF. The equations are solved by using a combination of analytical and numerical techniques to determine the mean velocity and the dispersion coefficient of molecules, and to determine the effect of various parameters on the separation efficiency of the EFFF device. Also, the model predictions are compared with experimental data available in the literature.
cDNA Labeling Strategies for Microarrays Using Fluorescent Dyes
Authors: Do J. H. , Choi D.‐K. 
Published: February 2007

AbstractMicroarray analysis has become a key experimental tool in the study of genome‐wide patterns of gene expression. The labeling step of target molecules such as cDNA or cRNA plays a key role in a microarray experiment because the amount of mRNA is measured indirectly by the labeled molecules. In this paper, the most widely used cDNA labeling strategies in microarray experiments are reviewed in detail, including direct labeling and indirect labeling methods along with a discussion of the merits and disadvantages of these methods. Furthermore, various RNA amplification approaches were surveyed to obtain a target nucleic acid sufficient for microarray experiments from minute amounts of mRNA. Finally, the labeling strategies of commonly used microarray platforms (e.g., Affymetrix GeneChip®, CodeLink™ Bioarray, Agilent and spotted microarrays) were compared.
Partial regression method to fit a generalized additive model
Authors: He Shui , Mazumdar Sati , Arena Vincent C. , Tang Gong 
Published: February 2007

AbstractGeneralized additive models (GAMs) have been used as a standard analytic tool in studies of air pollution and health during the last decade. The air pollution measure is usually assumed to be linearly related to the health indicator and the effects of other covariates are modeled through smooth functions. A major statistical concern is the appropriateness of fitting GAMs in the presence of concurvity. Generalized linear models (GLM) with natural cubic splines as smoothers (GLM + NS) have been shown to perform better than GAM with smoothing splines (GAM + S), in regard to the bias and variance estimates using standard model fitting methods. As nonparametric smoothers are attractive for their flexibility and easy implementation, search for alternative methods to fit GAM + S is warranted. In this article, we propose a method using partial residuals to fit GAM + S and call it the “partial regression” method. Simulation results indicate better performance of the proposed method compared togam.exactfunction in S‐plus, the standard tool in air pollution studies, in regard to bias and variance estimates. In addition, the proposed method is less sensitive to the degree of smoothing and accommodates asymmetric smoothers. Copyright © 2007 John Wiley & Sons, Ltd.
A sediment budget for a cultivated floodplain in tropical North Queensland, Australia
Authors: Visser Fleur , Roth Christian H. , Wasson Robert , Govers Gerard 
Published: February 2007

AbstractSugarcane is grown on the floodplains of northern Queensland adjacent to the Great Barrier Reef lagoon. Sediment and nutrient loss from these sugarcane areas is considered a potential threat to coastal and marine ecosystems. To enable sugarcane cultivation, farmers have structured the landscape into different elements, comprising fields, water furrows, ‘headlands’ and drains. In order to apply appropriate management of the landscape and reduce export of sediment, it is important to identify which of these elements act as sediment sources or sinks.In this study erosion and deposition rates were measured for the different landscape elements in a subcatchment of the Herbert River and used to create a sediment budget. Despite large uncertainties, the budget shows that the floodplain area is a net source of sediment. Estimated sediment export varies between 2 and 5 t ha−1 y−1. The relative importance of the landscape elements as sediment sources could also be determined. Plant cane is identified as the most important sediment source. Water furrows generate most sediment, but are a less important source of exported sediment due to their low connectivity. Headlands and minor drains act as sediment traps. Copyright © 2007 John Wiley & Sons, Ltd.
Vertical sedimentation units in a barrier island washover fan
Authors: Leatherman S. P. , Williams A. T. 
Published: February 2007

AbstractOverwash is a major component of a barrier island's response to high energy conditions. Examination of the 19‐20 March, 1975, storm deposits at Assateague Island, showed that an overwash sequence could be divided into sedimentation units. Interpretation depends upon defining textural and mineralogical combinations that can be logically ordered as a vertical sequence. If the sequence is depositional and formed from a single material, normal grading usually results; if polymineralogical and erosionally truncated, inverse grading with a top layer of heavy minerals can be formed via an in situ sorting process dependent on disturbance depth and overwash influence.
Systematic monthly morphologic variation of assawoman inlet: Nature and causes
Authors: Slingerland Rudy 
Published: February 2007

AbstractAssawoman Inlet, Virginia, U.S.A., representative of small mesotidal barrier island tidal inlets exhibits systematic variations of sediment volume among certain of its morphologic elements. Sediment volume variations were calculated from topographic‐bathymetric maps of the inlet system, as surveyed on 11 occasions at approximately monthly intervals by a fathometer, and plane table and alidade. Of 36 pairings among nine morphologic elements, seven show statistically significant Pearson Product Moment Correlation Coefficients. The southern ramp margin shoals are negatively correlated with the southern beach face and the northern ramp margin shoals are negatively correlated with the northern beach face on the northern spit. The southern and northern ramp margin shoals themselves are negatively correlated. The southern ramp margin shoals are negatively correlated with the fore flood tidal delta which is negatively correlated with a tidal channel on its landward side. The back flood tidal delta is positively correlated with the northern ramp margin shoals and negatively correlated with the back side of Wallops spit. These associations may be qualitatively explained using wave and tidal climate data during the sampling year plus megaripple and bedding orientations. Constructive waves tend to transfer sediment from the ramp margin shoals landward, building up the adjacent beach faces. Destructive waves tend to move sediment back to the ramp margin shoals. Waves striking the coast obliquely promote asymmetric growth of the shoals, causing the ebb jet to erode into whichever is the smaller shoal.
Autosuspension and the energetics of two‐phase flows: Reply to comments on ‘experimental test of autosuspension’ by J. B. Southard and M. E. Mackintosh
Authors: Paola Chris , Southard John B. 
Published: February 2007

AbstractThe experimental programme of Southard and Mackintosh (1981) provides a definitive refutation of the autosuspension criterion as it was originally defined. A simple energy budget for dilute two‐phase flow is derived from continuum theory of mixtures; it shows that Bagnold's criterion is based on an arbitrary comparison of two elements of the complete two‐phase system. It is recommended that facile, ab hoc criteria for the behaviour of such complex flows be avoided in favour of analyses based on fundamental equations of motion.
The deposition of stony colluvium on clay soil as a cause of gully formation in the Rif Mountains, Morocco
Authors: Van Brink J. W. Den , Jungerius P. D. 
Published: February 2007

AbstractV‐shaped gullies are formed on slopes in the Rif Mountains where stony colluvium covers a truncated Luvisol in finegrained, early pleistocene slope deposits. The colluvium resulted from large‐scale deforestation of summit areas in recent times. A number of properties related to the response of soil material to rainfall were investigated. Colluvium has a high infiltration capacity compared to the Luvisol. Consequently, the deposition of colluvium reduced overland flow and erosion by surface wash. Gully‐forming processes on the other hand were activated by the superposition of permeable over impermeable material.
Mathematical simulation of stable and equilibrium river bed profiles and slopes
Authors: Trofimov A. M. , Moskovkin V. M. 
Published: February 2007

AbstractTwo approaches to the simulation of stable and equilibrium longitudinal profiles and slopes are considered.The first one deals with a solution to the equation of solid matter (sediment) continuity in the equilibrium case and the second approach deals with the application of variational principles.The approaches considered and results obtained can be used in hydroengineering construction for designing stable and equilibrium longitudinal profiles of water streams and slopes.
Rainfall interception and splash detachment with a Brussels sprouts plant: A laboratory simulation
Authors: Noble Christine A. , Morgan R. P. C. 
Published: February 2007

AbstractRates of splash detachment from a sandy soil of the Cottenham Series, subjected to a five‐minute design storm of 50 mm/h with a kinetic energy of 127 J/m2 and a median volume drop size of 3·2 mm supplied from a rotating‐disc rainfall simulator, are determined without a plant cover and with the cover of a single Brussels sprouts plant. Measurements are made at regular intervals throughout the growing season. Plant canopies of 10 to 25 per cent result in reductions of 10 to 25 per cent in rainfall volume and 10 to 81 per cent in rainfall energy. The volume and energy of the rain beneath the plant are significantly (P < 0·05) correlated with its number of leaves (r = −0·84 and −0·92 respectively for n = 49). No reduction was observed in the rate of splash detachment which averages 1·2 kg/m2 for the design storm with and without the plant. The detachment rate was found rather surprisingly to be inversely related to the energy of the rainfall under the plant and positively related to the number of leaves. As the number of leaves increases, so does the detachment rate per unit of rainfall energy.