bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multiple origins of the cortical gamma rhythm
Authors: Whittington Miles A. , Cunningham Mark O. , LeBeau Fiona E.N. , Racca Claudia , Traub Roger D. 
Published: November 2010

AbstractGamma rhythms (30–80 Hz) are a near‐ubiquitous feature of neuronal population activity in mammalian cortices. Their dynamic properties permit the synchronization of neuronal responses to sensory input within spatially distributed networks, transient formation of local neuronal “cell assemblies,” and coherent response patterns essential for intercortical regional communication. Each of these phenomena form part of a working hypothesis for cognitive function in cortex. All forms of physiological gamma rhythm are inhibition based, being characterized by rhythmic trains of inhibitory postsynaptic potentials in populations of principal neurons. It is these repeating periods of relative enhancement and attenuation of the responsivity of major cell groups in cortex that provides a temporal structure shared across many millions of neurons. However, when considering the origins of these repeating trains of inhibitory events considerable divergence is seen depending on cortical region studied and mode of activation of gamma rhythm generating networks. Here, we review the evidence for involvement of multiple subtypes of interneuron and focus on different modes of activation of these cells. We conclude that most massively parallel brain regions have different mechanisms of gamma rhythm generation, that different mechanisms have distinct functional correlates, and that switching between different local modes of gamma generation may be an effective way to direct cortical communication streams. Finally, we suggest that developmental disruption of the endophenotype for certain subsets of gamma‐generating interneuron may underlie cognitive deficit in psychiatric illness. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 71: 92–106, 2011
Three groups of interneurons account for nearly 100% of neocortical GABAergic neurons
Authors: Rudy Bernardo , Fishell Gordon , Lee SooHyun , Hjerling‐Leffler Jens 
Published: November 2010

AbstractAn understanding of the diversity of cortical GABAergic interneurons is critical to understand the function of the cerebral cortex. Recent data suggest that neurons expressing three markers, the Ca2+‐binding protein parvalbumin (PV), the neuropeptide somatostatin (SST), and the ionotropic serotonin receptor 5HT3a (5HT3aR) account for nearly 100% of neocortical interneurons. Interneurons expressing each of these markers have a different embryological origin. Each group includes several types of interneurons that differ in morphological and electrophysiological properties and likely have different functions in the cortical circuit. The PV group accounts for ∼40% of GABAergic neurons and includes fast spiking basket cells and chandelier cells. The SST group, which represents ∼30% of GABAergic neurons, includes the Martinotti cells and a set of neurons that specifically target layerIV. The 5HT3aR group, which also accounts for ∼30% of the total interneuronal population, is heterogeneous and includes all of the neurons that express the neuropeptide VIP, as well as an equally numerous subgroup of neurons that do not express VIP and includes neurogliaform cells. The universal modulation of these neurons by serotonin and acetylcholine via ionotropic receptors suggests that they might be involved in shaping cortical circuits during specific brain states andbehavioral contexts. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 71: 45–61, 2011
Red Phosphorescence in RuII Complexes of a Tridentate N‐Heterocyclic Carbene Ligand Incorporating Tetrahydropyrimidine
Authors: Friese Viviane , Nag Samik , Wang Jianhua , Santoni Marie‐Pierre , Rodrigue‐Witchel Alexandre , Hanan Garry S. , Schaper Frank 
Published: November 2010

AbstractA new N‐heterocyclic carbene ligand N,N′‐bis(2‐pyridyl)‐tetrahydropyrimidinium hexafluorophosphate (1) has been synthesized and characterized. Its homoleptic RuII complex 2 exhibits a more facile oxidation (+1.17 V vs. SCE) relative to the prototypical [Ru(tpy)2]2+ (+1.32 V vs. SCE) complex (tpy = 2,2′:6′,2″‐terpyridine). The heteroleptic RuII complex 3, incorporating 1 and 4′‐p‐tolyl‐tpy, also displays a more positive oxidising potential (+1.28 V vs. SCE) than [Ru(tpy)2]2+. The X‐ray crystal structures of complexes 2 and 3 confirm the meridional tridentate coordination of ligand 1 to RuII. The Ru–C bond length is shorter in heteroleptic complex 3 [1.901(7) Å] than in homoleptic complex 2 [1.969(2) Å and 1.972(3) Å]. The complexes display broad metal‐to‐ligand charge‐transfer absorption bands in the visible region (2: λmax = 440 and 470 nm; 3: λmax = 440 and 473 nm), and their solid‐state emission is redshifted (2: λmax = 753 nm; 3: λmax = 735 nm) considerably relative to that of [Ru(tpy)2]2+ (λmax = 620 nm).
Recent developments in the methodology and application of MEEKC
Authors: Ryan Richie , McEvoy Eamon , Sheila Donegan  , Power Joe , Altria Kevin 
Published: November 2010

AbstractMEEKC is an electrodriven separation technique that utilises the unique properties of a microemulsion (ME) as a background electrolyte to achieve separation of a diverse range of solutes. MEs are composed of nanometre‐sized oil droplets suspended in aqueous buffer, which is commonly referred to as oil‐in‐water ME. The droplets are stabilised by the presence of both a surfactant and co‐surfactant. The use of water‐in‐oil MEs in MEEKC has also been investigated. This review details the advances in MEEKC‐based separations from the period June 2008 – June 2010. Areas covered include online sample concentration, suppressed electroosmosis MEEKC, chiral separations, MEEKC‐MS, MEEKC‐ICP‐MS and ME structure characterisation. The review also includes a fundamental introduction to MEEKC, along with a review of recent applications.
Recent advances in CE‐MS: Synergy of wet chemistry and instrumentation innovations
Authors: Pantůčková Pavla , Gebauer Petr , Boček Petr , Křivánková Ludmila 
Published: November 2010

AbstractCE with MS detection is a hyphenated technique which greatly improves the ability of CE to deal with real samples, especially with those coming from biology and medicine, where the target analytes are present as trace amounts in very complex matrices. CE‐MS is now almost a routine technique performed on commercially available instruments. It faces currently a tremendous development of the technique itself as well as of its wide application area. Great interest in CE‐MS is reflected in the scientific literature by many original research articles and also by numerous reviews. The review presented here has a general scope and belongs to a series of regularly published reviews on the topic. It covers the literature from the last 2 years, since January 2008 till June 2010. It brings a critical selection of related literature sorted into groups reflecting the main topics of actual scientific interest: (i) innovations in CE‐ESI‐MS, (ii) use of alternative interfaces, and (iii) ways to enhance sensitivity. Special attention is paid to novel electrolyte systems amenable to CE‐MS including nonvolatile BGEs, to advanced CE separation principles such as MEKC, MEEKC, chiral CE, and to the use of preconcentration techniques.
Recent advances in the MS analysis of glycoproteins: Theoretical considerations
Authors: Lazar Iulia M. , Lazar Alexandru C. , Cortes Diego F. , Kabulski Jarod L. 
Published: November 2010

AbstractProtein glycosylation is involved in a broad range of biological processes that regulate protein function and control cell fate. As aberrant glycosylation has been found to be implicated in numerous diseases, the study and large‐scale characterization of protein glycosylation is of great interest not only to the biological and biomedical research community, but also to the pharmaceutical and biotechnology industry. Due to the complex chemical structure and differing chemical properties of the protein/peptide and glycan moieties, the analysis and structural characterization of glycoproteins has been proven to be a difficult task. Large‐scale endeavors have been further limited by the dynamic outcome of the glycosylation process itself, and, occasionally, by the low abundance of glycoproteins in biological samples. Recent advances in MS instrumentation and progress in miniaturized technologies for sample handling, enrichment and separation, have resulted in robust and compelling analysis strategies that effectively address the challenges of the glycoproteome. This review summarizes the key steps that are involved in the development of efficient glycoproteomic analysis methods, and the latest innovations that led to successful strategies for the characterization of glycoproteins and their corresponding glycans. As a follow‐up to this work, we review innovative capillary and microfluidic‐MS workflows for the identification, sequencing and characterization of glycoconjugates.
The application of terrestrial laser scanning to aeolian saltation cloud measurement and its response to changing surface moisture
Authors: Nield Joanna M. , Wiggs Giles F.S. 
Published: November 2010

AbstractSaltation is the dominant form of aeolian transport of sand sized grains, yet its heterogeneous spatial and temporal distribution, and inherent feedback and interaction with the surface over which sand is transported, hinders large scale quantification. In this letter we present preliminary data on saltation cloud characteristics quantified using terrestrial laser scanning (TLS). These data, together with surface moisture and surface roughness patterns, elucidate the importance of saltation in the development of protodunes on a drying beach, and indicate the potential usefulness of TLS in examining aeolian processes in both beach and desert environments. Copyright © 2010 John Wiley & Sons, Ltd.
Evaluation of a humidity‐measuring instrument for the determination of water in spray‐dried flavour powders
Authors: Veazey Robert L. , Bockhorn Brian , Golding Robert , Wu Anna 
Published: November 2010

AbstractSpray drying is a common technique for encapsulation of liquid and dry flavours. Control of the water content of spray‐dried flavour powders is critical for maintaining product quality and storage stability. Karl Fischer titration is the method of choice for confirming that the product meets specifications, but a simpler technique would be welcome in the quality control laboratory. We report here the results of an evaluation of a humidity‐measuring instrument, the Computrac® Vapor Pro®, for determining the water content of spray‐dried flavour powders. The instrument heats the sample to drive off moisture, which is measured with a water‐specific sensor. The influence of the oven temperature, sample size, purge time, and endpoint detection method were determined for our samples. The optimized Vapor Pro® measurements show excellent correlation (r2 = 0.9923, n = 51) with the reference Karl Fischer method over a range of 1.3% to 7.4% water, with comparable precision. The instrument is thus capable of replacing a Karl Fischer titrator for at‐line monitoring and QC evaluation of water in spray‐dried flavours.
Development of high intensity focused ultrasound simulator for large‐scale computing
Authors: Okita Kohei , Ono Kenji , Takagi Shu , Matsumoto Yoichiro 
Published: November 2010

AbstractHigh intensity focused ultrasound (HIFU) has been developed as a noninvasive therapeutic option. HIFU simulations are required to support the development of the HIFU device as well as the realization of noninvasive treatments. In this study, an HIFU simulator is developed that uses voxel data constructed from computed tomography scan data on the living human body and signed distance function (SDF) data to represent the object. The HIFU simulator solves the conservation equations of mass and momentum for mixtures with the equation of state for each medium. The numerical method is the finite‐difference time‐domain method. A high‐order finite‐difference method based on Lagrange interpolation is implemented to reduce numerical phase error. This approach reproduces wave propagation to an nth order of accuracy. Representation of the sound source by volume fraction, which is obtained from the SDF using a smoothed Heaviside function, provides around 1.66th order of accuracy in the spherical wave problem. As a realistic application, transcranial HIFU therapy for a brain tumor is modeled, where tissue inhomogeneity causes not only displacement of the focal point but also diffusion of the focused ultrasound. Even in such cases, focus control using phase delays, which are pre‐computed based on the time‐reversal procedure, enables correct focal point targeting as well as improved ultrasound focusing. Copyright © 2010 John Wiley & Sons, Ltd.
Interfacial flow computations using adaptive Eulerian–Lagrangian method for spacecraft applications
Authors: Sim Jaeheon , Shyy Wei 
Published: November 2010

SUMMARYUnderstanding the interfacial dynamics and fluid physics associated with the operation of spacecraft is important for scientific as well as engineering purposes. To help address the issues associated with moving boundaries, interfacial dynamics, and spatial‐temporal variations in time and length scales, a 3‐D adaptive Eulerian–Lagrangian method is extended and further developed. The stationary (Eulerian) Cartesian grid is adopted to resolve the fluid flow, and the marker‐based triangulated moving (Lagrangian) surface meshes are utilized to treat the phase boundary. The key concepts and numerical procedures, along with the selected interfacial flow problems are presented. Specifically, the liquid fuel draining dynamics in different flow regimes, and the liquid surface stability under vertically oscillating gravitational acceleration are investigated. Direct assessment of experimental measurement and scaling analysis is made to highlight the computational performance of the present approach as well as the key fluid physics influenced by the given flow parameters. Copyright © 2010 John Wiley & Sons, Ltd.
A high‐order upwind control‐volume method based on integrated RBFs for fluid‐flow problems
Authors: Mai‐Duy N. , Tran‐Cong T. 
Published: November 2010

AbstractThis paper is concerned with the development of a high‐order upwind conservative discretization method for the simulation of flows of a Newtonian fluid in two dimensions. The fluid‐flow domain is discretized using a Cartesian grid from which non‐overlapping rectangular control volumes are formed. Line integrals arising from the integration of the diffusion and convection terms over control volumes are evaluated using the middle‐point rule. One‐dimensional integrated radial basis function schemes using the multiquadric basis function are employed to represent the variations of the field variables along the grid lines. The convection term is effectively treated using an upwind scheme with the deferred‐correction strategy. Several highly non‐linear test problems governed by the Burgers and the Navier–Stokes equations are simulated, which show that the proposed technique is stable, accurate and converges well. Copyright © 2010 John Wiley & Sons, Ltd.
A Stokes model with cavitation for the numerical simulation of hydrodynamic lubrication
Authors: Nilsson B. , Hansbo P. 
Published: November 2010

AbstractWe present a cavitation model based on the Stokes equation and formulate adaptive finite element methods for its numerical solution. A posteriori error estimates and adaptive algorithms are derived, and numerical examples illustrating the theory are supplied, in particular with comparison to the simplified Reynolds model of lubrication. Copyright © 2010 John Wiley & Sons, Ltd.
Simulation of two‐phase flow with moving immersed boundaries
Authors: Holmvall M. , Lindström S. B. , Uesaka T. 
Published: November 2010

AbstractA two‐dimensional multi‐phase model for immiscible binary fluid flow including moving immersed objects is presented. The fluid motion is described by the incompressible Navier–Stokes equation coupled with a phase‐field model based on van der Waals' free energy density and the Cahn–Hilliard equation. A new phase‐field boundary condition was implemented with minimization of the free energy in a direct way, to specifically improve the physical behavior of the contact line dynamics for moving immersed objects. Numerical stability and execution time were significantly improved by the use of the new boundary condition. Convergence toward the analytical solution was demonstrated for equilibrium contact angle, the Lucas–Washburn theory and Stefan's problem. The proposed model may be used for multi‐phase flow problems with moving boundaries of complex geometry, such as the penetration of fluid into a deformable, porous medium. Copyright © 2010 John Wiley & Sons, Ltd.
Wideband fast multipole boundary element method: Application to acoustic scattering from aerodynamic bodies
Authors: Wolf W. R. , Lele S. K. 
Published: November 2010

AbstractA wideband adaptive multi‐level fast multipole method (MLFMM) is used to accelerate the matrix–vector products arising from a boundary element method (BEM) formulation which solves the Burton–Miller boundary integral equation (BIE). The wideband MLFMM presented here applies a plane wave expansion formulation with fast interpolation and filtering for calculations in the high‐frequency regime and a partial wave expansion formulation with rotation‐coaxial translation in the low‐frequency regime. The iterative solvers GMRES, Bi‐CGSTAB and CGS are tested and compared and a block diagonal preconditioner is used to improve the condition number of the BEM matrices and to accelerate the convergence of the iterative solvers. Details on the implementation of the formulations are described, including the treatment of singular integrals. Results for acoustic scattering from a wing plus engine nacelle configuration for a prescribed source in a subsonic uniform flow are presented for a broad range of frequencies in order to assess the implemented capability. Copyright © 2010 John Wiley & Sons, Ltd.
Fundamental validation of the finite volume particle method for 3D sloshing dynamics
Authors: Guo Lian Cheng , Zhang Shuai , Morita Koji , Fukuda Kenji 
Published: November 2010

AbstractThe use of the finite volume particle (FVP) method is validated for three‐dimensional sloshing dynamics with a free surface by comparing with results from experiments. In the first part, two typical sloshing experiments for a single liquid phase are simulated, and slosh characteristics that include the free surface behavior and hydrodynamic pressure are reported. Moreover, the influences of the circular wall geometry and spatial resolution in the simulation are studied in a sensitivity analysis. In the second part, two sloshing problems with solid bodies are simulated to preliminarily verify the applicability of the FVP method to three‐dimensional solid bodies' motion in liquid flow. Good agreement between simulations and corresponding experiments indicates that the present FVP method well reproduces three‐dimensional sloshing behavior. Copyright © 2010 John Wiley & Sons, Ltd.
Environmental fate of pyrethroids in urban and suburban stream sediments and the appropriateness of Hyalella azteca model in determining ecological risk
Authors: Palmquist Katherine , Fairbrother Anne , Salatas Johanna , Guiney Patrick D. 
Published: November 2010

Abstract
According to several recent studies using standard acute Hyalella azteca sediment bioassays, increased pyrethroid use in urban and suburban regions in California has resulted in the accumulation of toxic concentrations of pyrethroids in sediments of area streams and estuaries. However, a critical review of the literature indicates that this is likely an overestimation of environmental risk. Hyalella azteca is consistently the most susceptible organism to both aqueous and sediment-associated pyrethroid exposures when compared to a suite of other aquatic taxa. In some cases, H. azteca LC50 values are less than the community HC10 values, suggesting that the amphipod is an overly conservative model for community- or ecosystem-level impacts of sediment-associated pyrethroids. Further, as a model for responses of field populations of H. azteca, the laboratory bioassays considerably overestimate exposure, because the amphipod is more appropriately characterized as an epibenthic organism, not a true sediment dweller; H. azteca preferentially inhabit aquatic macrophytes, periphyton mats, and leaf litter, which drastically reduces their exposure to contaminated sediments. Sediment-bound pyrethroids are transported via downstream washing of fine particulates resulting in longer range transport but also more efficient sequestration of the chemical. In addition, site-specific variables such as sediment organic carbon content, grain size, temperature, and microbial activity alter pyrethroid bioavailability, degradation, and toxicity on a microhabitat scale. The type and source of the carbon in particular, influences the pyrethroid sequestering ability of sediments. The resulting irregular distribution of pyrethroids in stream sediments suggests that sufficient nonimpacted habitat may exist as refugia for resident sediment-dwelling organisms for rapid recolonization to occur. Given these factors, we argue that the amphipod model provides, at best, a screening level assessment of pyrethroid impacts and can correctly identify those sediments not toxic to benthic organisms but cannot accurately predict where sediments will be toxic. Integr Environ Assess Manag 2011;7:325–335. © 2011 SETAC
Synthesis of [13C5] and [carbonyl‐14C]‐5‐chlorofuran‐2‐carboxylic acid
Authors: Dorff Peter N. , Powell Mark E. , Elmore Charles S. 
Published: November 2010

AbstractThe inventory of labeled compounds and methods for their preparation are constantly growing, but still more building blocks of biologically relevant compounds need to be developed. Furans are frequently encountered in bioactive molecules, and a good synthesis of labeled furan is found in the literature. We required a relatively uncommon labeled furan, 5‐chloro‐2‐furoic acid, for investigative work labeled with C‐13 and C‐14. Carboxylation of the lithium anion of [13C4]furan with 13CO2 followed by chlorination using benzyltrimethylammonium dichloroiodate provided the target compound in modest yield and high purity. The same procedure was then repeated with unlabeled furan and 14CO2 to give [carbonyl‐14C]‐5‐chlorofuran‐2‐carboxylic acid. Copyright © 2010 John Wiley & Sons, Ltd.