bluuebunny/crossref_metadata_2025 huggingface dataset:
EEG alpha oscillations in the preparation for global and local processing predict behavioral performance
Authors: Volberg Gregor , Kliegl Katrin , Hanslmayr Simon , Greenlee Mark W.
Published: October 2008

Visual attention can be directed either to the global features of a display or to the local elements that make up the display. We investigated whether oscillatory brain responses to globally or locally directed cue stimuli predict behavioral performance in subsequent target processing. Induced alpha band (8–12 Hz) amplitudes in the pre‐stimulus interval were measured separately for the global and the local level, where individual trials were assigned to one of three groups according to the response speed towards incongruent stimuli. Fast responses to local features were associated with high alpha amplitudes in the right centro‐parietal cortex, whereas fast responses to global forms were associated with high alpha in left centro‐parietal cortex. For trials with slower responses, the pattern of hemispheric differences was diminished or even reversed. It is interpreted that the left and the right parietal cortex exert top–down control over hierarchical processing by inhibiting stimulus representations in one hemisphere. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.
Analyzing brain networks with PCA and conditional Granger causality
Authors: Zhou Zhenyu , Chen Yonghong , Ding Mingzhou , Wright Paul , Lu Zuhong , Liu Yijun
Published: October 2008

Identifying directional influences in anatomical and functional circuits presents one of the greatest challenges for understanding neural computations in the brain. Granger causality mapping (GCM) derived from vector autoregressive models of data has been employed for this purpose, revealing complex temporal and spatial dynamics underlying cognitive processes. However, the traditional GCM methods are computationally expensive, as signals from thousands of voxels within selected regions of interest (ROIs) are individually processed, and being based on pairwise Granger causality, they lack the ability to distinguish direct from indirect connectivity among brain regions. In this work a new algorithm called PCA based conditional GCM is proposed to overcome these problems. The algorithm implements the following two procedures: (i) dimensionality reduction in ROIs of interest with principle component analysis (PCA), and (ii) estimation of the direct causal influences in local brain networks, using conditional Granger causality. Our results show that the proposed method achieves greater accuracy in detecting network connectivity than the commonly used pairwise Granger causality method. Furthermore, the use of PCA components in conjunction with conditional GCM greatly reduces the computational cost relative to the use of individual voxel time series. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.
Hierarchical functional modularity in the resting‐state human brain
Authors: Ferrarini Luca , Veer Ilya M. , Baerends Evelinda , van Tol Marie‐José , Renken Remco J. , van der Wee Nic J.A. , Veltman Dirk. J. , Aleman André , Zitman Frans G. , Penninx Brenda W.J.H. , van Buchem Mark A. , Reiber Johan H.C. , Rombouts Serge A.R.B. , Milles Julien
Published: October 2008

Functional magnetic resonance imaging (fMRI) studies have shown that anatomically distinct brain regions are functionally connected during the resting state. Basic topological properties in the brain functional connectivity (BFC) map have highlighted the BFC's small‐world topology. Modularity, a more advanced topological property, has been hypothesized to be evolutionary advantageous, contributing to adaptive aspects of anatomical and functional brain connectivity. However, current definitions of modularity for complex networks focus on nonoverlapping clusters, and are seriously limited by disregarding inclusive relationships. Therefore, BFC's modularity has been mainly qualitatively investigated. Here, we introduce a new definition of modularity, based on a recently improved clustering measurement, which overcomes limitations of previous definitions, and apply it to the study of BFC in resting state fMRI of 53 healthy subjects. Results show hierarchical functional modularity in the brain. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.
Inhibition dominates in shaping spontaneous CA3 hippocampal network activities in vitro
Authors: Ho Ernest C.Y. , Zhang Liang , Skinner Frances K.
Published: October 2008

We have assessed the balance of excitation and inhibition in in vitro rodent hippocampal slices exhibiting spontaneous, basal sharp waves (bSPWs). A defining signature of a network exhibiting bSPWs is the rise and fall in local field activities with frequencies ranging from 0.5 to 4.5 Hz. This variation of extracellular local field activities manifests at the intracellular level as postsynaptic potentials (PSPs). In correspondence with the local field bSPWs, we consider “sparse” and “synchronous” parts of bSPWs at the intracellular level. We have used intracellular data of bSPW‐associated PSPs together with mathematical extraction techniques to quantify the mean and variance of synaptic conductances that a neuron experiences during bSPW episodes. We find that inhibitory conductances dominate in pyramidal cells and in a putative interneuron, and that inhibitory variances are much greater than excitatory ones during synchronous parts of bSPWs. Specifically, we find that there is at least a twofold increase in inhibitory conductance dominance from “sparse” to “synchronous” bSPW states and that this transition is associated with inhibitory fluctuations of greater than 10% of the change in mean inhibitory conductance. On the basis of our findings, we suggest that such inhibitory fluctuations during transition may be a physiological feature of systems expressing such population activities. In summary, our results provide a quantified basis for understanding the interaction of excitatory and inhibitory neuronal subpopulations in bSPW activities. © 2008 Wiley‐Liss, Inc.
Quantitative transcriptional neuroanatomy of the rat hippocampus: Evidence for wide‐ranging, pathway‐specific heterogeneity among three principal cell layers
Authors: Greene James G. , Borges Karin , Dingledine Raymond
Published: October 2008

We have used laser‐capture microdissection and microarray hybridization to characterize gene expression in the three principal neuron layers of rat hippocampus. Correlative and clustering analyses revealed all three layers to be easily differentiated from one another based on gene expression profile alone. A greater disparity in gene expression exists between dentate granule and pyramidal cell layers, reflecting phenotypic and ontological differences between those cell populations. Remarkably, the level of more than 45% of expressed transcripts was significantly different among the three neuron populations, with more than a third of those (>1,000 transcripts) being at least twofold different between layers. Even CA1 and CA3 pyramidal cell layers were dramatically different on a transcriptional level with a separate analysis indicating that nearly 20% of transcripts are differentially expressed between them. Only a small number of transcripts were specific for a given hippocampal cell layer, suggesting that functional differences are more likely secondary to wide‐ranging expression differences of modest magnitude rather than very large disparities in a few genes. Categorical analysis of transcript abundance revealed concerted differences in gene expression among the three cell layers referable to specific cellular pathways. For instance, transcripts encoding proteins involved in glucose metabolism are most highly expressed in the CA3 pyramidal layer, which may reflect an underlying greater metabolic rate of these neurons and partially explain their exquisite vulnerability to seizure‐induced damage. Conversely, transcripts related to MAP kinase signaling pathways and transcriptional regulator activity are prominent in the dentate granule cell layer, which could contribute to its resistance to damage following seizure activity by positioning these neurons to respond to external stimuli by altering transcription. Taken together, these data suggest that unique physiological characteristics of major cell layers, such as neuronal activity, neuronal plasticity, and vulnerability to neurodegeneration, are reflected in substantial transcriptional heterogeneity within the hippocampus. © 2008 Wiley‐Liss, Inc.
Influence of presence of tannic acid on removal of sodium dodecylbenzenesulphonate by O3 and advanced oxidation processes
Authors: Sánchez‐Polo M. , Méndez‐Díaz J.D. , Rivera‐Utrilla J. , Bautista‐Toledo M.I. , Ferro‐Garcia M.A.
Published: October 2008

BACKGROUND: The objective of the present investigation was to determine the role of the tannic acid (TAN) component of organic matter dissolved in water, in the removal of sodium dodecylbenzenesulphonate (SDBS) by ozone and by O3/H2O2, O3/granular activated carbon (GAC) and O3/powdered activated carbon (PAC) advanced oxidation processes.

RESULTS: Low doses of TAN (1 mg L−1) during SDBS ozonation cause (i) an increased ozone decomposition rate and (ii) an increased SDBS removal rate. The SDBS removal rate with ozone in the presence of TAN was reduced when HCO3− ions were added. A rise in TAN concentration increased the SDBS removal rate, with a linear relationship between added TAN and the removal rate. SDBS was removed more effectively by O3/GAC, O3/PAC and O3/H2O2 systems in the presence of TAN.

CONCLUSIONS: Results obtained indicated two mechanisms involved in the generation of HO· radicals by the O3/TAN interaction: (i) direct generation of HO· radicals from the reaction between ozone and TAN, and (ii) increased generation of O2−· radicals in the medium, enhancing the transformation of ozone into HO· radicals by different radical reactions. In O3/GAC and O3/PAC systems, HO· radicals are mainly generated in the O3/TAN interaction, which is a homogeneous reaction with fast kinetics, whereas the O3/GAC and O3/PAC interactions are in a heterogeneous phase with much slower kinetics, and are therefore not competitive in the generation of HO· radicals. Copyright © 2008 Society of Chemical Industry
Mitochondrial DNA phylogeography of Caiman crocodilus in Mesoamerica and South America
Authors: Venegas‐Anaya Miryam , Crawford Andrew J. , Escobedo Galván Armando H. , Sanjur Oris I. , Densmore Llewellyn D. , Bermingham Eldredge
Published: October 2008

The Neotropical crocodylian species, Caiman crocodilus, is widely distributed through Mesoamerica, northern South America, and the Amazon basin. Four subspecies are recognized within C. crocodilus, suggesting some geographic variation in morphology. In this study, we utilized mitochondrial DNA (mtDNA) sequence data from 45 individuals of C. crocodilus throughout its range to infer its evolutionary history and population structure, as well as to evaluate genealogical support for subspecies and their geographic distributions. Our molecular phylogenetic results identified five mtDNA haplotype clades with a mean sequence divergence of 3.4%, indicating considerable evolutionary independence among phylogeographic lineages. Our results were also broadly consistent with current subspecific taxonomy, with some important additional findings. First, we found substantial genetic structuring within C. c. fuscus from southern Mesoamerica. Second, though we confirmed the existence of a widespread Amazonian clade, we also discovered a cryptic and divergent mtDNA lineage that was indistinguishable from C. c. crocodilus based on external morphology. Third, we confirm the status of C. c. chiapasius as a distinct evolutionary lineage, and provide evidence that C. c. fuscus may be moving northward and hybridizing with C. c. chiapasius in northern Mesoamerica. Finally, our results parallel previous phylogeographic studies of other organisms that have demonstrated significant genetic structure over shorter geographic distances in Mesoamerica compared with Amazonia. We support conservation efforts for all five independent lineages within C. crocodilus, and highlight the subspecies C. c. chiapasius as a unit of particular conservation concern. J. Exp. Zool. 309A:614–627, 2008. © 2008 Wiley‐Liss, Inc.
The less than sweet solution to Fiji's sugar industry problems
Authors: Mahadevan Renuka
Published: October 2008

The loss of EU sugar preferences at the end of 2007 has made the push for reform more urgent than ever in the African, Caribbean and Pacific (ACP) countries. Fiji as a case study is useful to understand the difficulties faced in being competitive in the global market without the sugar subsidy. Using farm level survey, it was found that on average, technical efficiency (TE) was only about 72%, and that farm size should be expanded to gain from returns to scale. Empirical investigation and discussion shows that low efficiency is caused by lack of land tenure, poor infrastructural support, inefficiency in sugar institutions and the inadequate adoption of best farm practices. It is evident that the tight vertical integration of the industry necessitates an integrated and holistic approach to policy implementation. Copyright © 2008 John Wiley & Sons, Ltd.
Putting leakage in its place: The significance of retained tourism revenue in the local context in Rural Uganda
Authors: Sandbrook Chris G.
Published: October 2008

It is often argued that leakage of tourism revenue results in minimal economic benefits for host communities, particularly in rural areas of developing countries. However, leakage studies often employ flawed methods, and rarely compare retained revenue with other sources of income to such areas, which can be limited. This paper estimates these values for gorilla tracking tourism at Bwindi Impenetrable National Park, Uganda. Leakage was over 75%, but retained revenue was nevertheless greater than all other sources of revenue to the area combined. It is therefore argued that tourism can be highly significant in the local context despite considerable leakage. Copyright © 2008 John Wiley & Sons, Ltd.
Ultrastructural and temporal changes of the microvascular basement membrane and astrocyte interface following focal cerebral ischemia
Authors: Kwon Il , Kim Eun Hee , del Zoppo Gregory J. , Heo Ji Hoe
Published: October 2008

Microvascular integrity is lost during cerebral ischemia. Detachment of the microvascular basement membrane (BM) from the astrocyte, as well as degradation of the BM, is responsible for the loss of microvascular integrity. However, their ultrastructural and temporal changes during cerebral ischemia are not well known. Male Sprague‐Dawley rats were subjected to permanent middle cerebral artery occlusion (MCAO) for 1, 4, 8, 12, 16, 20, and 48 hr. By using transmission electron microscopy, the proportion of intact BM–astrocyte contacts and electron densities of the BM were measured from five randomly selected microvessels in the ischemic basal ganglia. Their temporal changes and associations with activities of the matrix metalloproteinases (MMPs) were investigated. The intact portion of the BM–astrocyte contacts was decreased significantly within 4 hr and was rarely observed at 48 hr after MCAO. Decreases in the electron density and degradation of the BM were significant 12 hr after MCAO. The intact BM–astrocyte contacts and the mean BM density showed a significant positive correlation (r = 0.784, P < 0.001). MMP‐9 activity was correlated negatively with the intact BM–astrocyte contacts (r = –0.711, P < 0.001) and with the BM density (r = –0.538, P = 0.0016). The increase in MMP‐9 coincided temporally with the loss of the BM–astrocyte contacts and a decrease in the BM density. Ultrastructural alterations occurring in the microvascular BM and its contacts with astrocyte endfeet were temporally associated in cerebral ischemia. Time courses of their alterations should be considered in the treatment targeted to the microvascular BM and its contact with astrocytes. © 2008 Wiley‐Liss, Inc.
Bradykinin selectively modulates the blood–tumor barrier via calcium‐induced calcium release
Authors: Wang Yi‐bao , Liu Yun‐hui
Published: October 2008

To investigate the underlying mechanism for the selective modulation of permeability of the blood–tumor barrier by small dose of BK, we established cell lines of rat brain microvascular endothelial cells (BMECs) and astrocytes by primary culture from neonatal rats. BMECs, astrocytes, or C6 glioma cells were treated with BK, and changes of intracellular NO and intracellular calcium level were measured with a fluorescent spectrophotometer. Similarly to the observations in astrocytes, although the initial application of BK easily triggered a ryanodine‐mediated calcium‐induced calcium release (CICR), we also detected a long‐lasting intracellular nitric oxide (NO) elevation in C6 glioma cells upon BK treatment. However, BMECs are not the direct target of BK. Further study showed that ryanodine‐mediated CICR contributes greatly to the secondary NO elevation induced by BK treatment. With an in vitro blood–tumor barrier (BTB) model, we demonstrated that NO generated in C6 glioma cells might act as an intercellular messenger and play an important role in the selective modulation of permeability of BMECs by BK. In conclusion, BK triggered CICR in C6 glioma cells, and the associated NO generation might be the underlying mechanism for the selective modulation of BTB permeability by BK. © 2008 Wiley‐Liss, Inc.
Capacity for public administration: analysis of meaning and measurement
Authors: Christensen Robert K. , Gazley Beth
Published: September 2008

Public administration researchers and practitioners have placed a heavy emphasis on the theme of programme performance. More recently, there has been a growing sentiment in the literature about the integral role of organisational capacity in achieving performance. While this is often expressed in the (re)iteration of a ‘management matters’ mantra, we see some disarray in the broader capacity literature both in definition and application. As scholars call for more integrated models of governance that link, for example, capacity and performance, we see a growing need for an analysis of the concept of capacity. Using bibliometric and content analyses to explore scholarly treatment of capacity constructs, this article assesses whether the perceived disarray is real, and if so what consequences it might have. We do so by reporting on capacity's meaning and measurement through an analysis of four decades of the private, public and nonprofit management literatures. While specific definitions of capacity are, by nature, context dependent, we conclude by distilling a general, conceptual framework of capacity for public management researchers and practitioners. Copyright © 2008 John Wiley & Sons, Ltd.
Public sector reform in Sub‐Saharan Africa: what can be learnt from the civil service performance improvement programme in Ghana?
Authors: Antwi K. B. , Analoui F. , Nana‐Agyekum D.
Published: September 2008

This paper focuses on public sector management reform ‘best‐practice’ case experience from Sub‐Sahara African (SSA). Given that ‘best‐practice’ is a relative concept and often debatable, the paper uses the Ghana Civil Service Performance Improvement Programme (GCSPIP) experience as rather a ‘good‐practice’ case with the view to sharing the outcome and lessons to encourage collaborative‐learning. It seeks to share the outcome and lessons learnt by the Ghana civil service reform with future public service reformers and to contribute to the literature. The paper concludes with an adaptable three‐dimensional framework. The framework argues that successful future public service reform (PSR) should consider three broad issues: first, are the ‘critical success factors’, including wholehearted political leadership commitment; wholehearted bureaucratic leadership commitment; thoughtful synergistic planning/preparation; patience for implementation and evaluation; capacity to convince; neutralise and accommodate reform‐phobias and critics; sustainable financial and technical resource availability and conscious nurturing of general public support. Second, is the need for reformers to appreciate the concerns of the public and the civil society scepticism of public ‘institutions’ and its ‘operatives’ and finally placing any reform programme in a country‐specific context, including understanding its history, culture, politics, economy, sociology, ideology and values. Copyright © 2008 John Wiley & Sons, Ltd.
In search of a governance institution model for Jakarta Metropolitan Area (JMA) under Indonesia's new decentralisation policy: old problems, new challenges
Authors: Firman Tommy
Published: September 2008

This study explores a possible governance model for Jakarta Metropolitan Area (JMA) under Indonesia's new Decentralisation Policy. At present the management of JMA development is coordinated by Badan Koordinasi Pembangunan Jabodetabekjur (BKSP) —Coordinating Board for JMA Development, but this agency is ineffective and powerless to perform its tasks because of lack of authority and power. The establishment of JMA governance model should take into account the existence of the BKSP which has been politically accepted by all provincial and local governments in the region. Involvement of central government in JMA governance is very important. A mixed model of urban governance is most suitable for the JMA. Thereunder the central government should have authority to plan and develop major physical infrastructure for the whole JMA, while the provincial and local governments retain their respective general administrative functions. Copyright © 2008 John Wiley & Sons, Ltd.
Beyond public administration? HIV/AIDS policy networks and the transformation of public administration in Botswana
Authors: Kaboyakgosi Gape , Mpule Keneilwe P.
Published: September 2008

What impact has HIV/AIDS had on the structure of public administration and what further lessons do these changes hold for other policy sectors in Botswana? For long, Botswana has had the highest prevalence of HIV/AIDS, bringing many developmental challenges. An under‐researched facet of HIV/AIDS is the effect it had on the public administration in Botswana. Whereas classical approaches to public administration suggest that it is ‘civil’ service organisations that lead in health administration, HIV/AIDS spawned a particular type of organisation, the policy network. In mitigating HIV/AIDS, the policy environment became more fragmented with networks for treatment, prevention, advocacy and research emerging. These networks are made up of entities from the public, private for‐profit and not for‐profit sectors. They participate in the agenda setting, formulation, implementation and monitoring and evaluation of HIV/AIDS policy. Traditional public administration theories cease to hold sway; private actors become engaged in ‘public policy’ and the other way round. Policy is carried out in horizontal arrangements; linking government, business and non‐governmental organisations in mutual inter‐dependences. Health care professionals share policy spaces with the media, social scientists and politicians. New challenges face public policy‐making including co‐ordination problems, fragmented accountability and shared policy spaces. Copyright © 2008 John Wiley & Sons, Ltd.
Assessing the regulatory model for water supply in Jakarta
Authors: Iwanami Michiko , Nickson Andrew
Published: September 2008

This article assesses the regulatory model for urban water supply services in Jakarta, the capital of Indonesia. Water supply services have been privately operated there since February 1998 after two companies—Thames PAM Jaya (TPJ), operating in Eastern Jakarta, and PAM Lyonnaise Jaya (PALYJA), operating in Western Jakarta—signed 25‐years concession contracts with the state‐owned Jakarta City Water Company (PAM Jaya). An independent regulatory body, the Jakarta Water Supply Regulatory Body (JWSRB) was established in 2001. The article compares the regulatory system in Jakarta with the French and English approaches to water regulation. It then assesses this regulatory system from the perspective of customers in order to assess how well customer protection, a central purpose of regulation, is being performed. The article concludes that although the essential regulatory mechanisms and activities are operating in Jakarta, the key regulatory role of customer protection is not being performed because customers do not perceive that they receive an acceptable level of water supply services. Copyright © 2008 John Wiley & Sons, Ltd.
Applying rapid results approach to local service delivery: issues, lessons and challenges from Nairobi City Council
Authors: Osiche Mark
Published: September 2008

Over the years, the Kenyan Government has pursued wide‐ranging public sector reforms to improve local service delivery, but little has been achieved due to lack of a wide‐ranging decentralisation policy and institutional framework. To precipitate the reform process, the rapid results approach (RRA), commonly applied in private sector organisations, was recently introduced thorough out the public sector, including local authorities (LAs). This article assesses the efficacy of the rapid results approach (RRA) methodology in local service delivery using Nairobi City Council as a prototype; highlighting the success stories, pitfalls and challenges. The analyses are based on the findings obtained using current literature on the subject matter and the author's interactions with the council staff, councillors and other stakeholders. On the basis of the analysis, the article draws the main conclusions and policy advice on what could be considered critical for further debate, highlighting issues, lessons and challenges that could be raised to improve the practice of RRI. The key messages presented here will help policy makers, scholars and practitioners of reform to re‐think the envisaged countrywide replication of RRI to the rest of LAs. Copyright © 2008 John Wiley & Sons, Ltd.
The mechanism of the oxidative polymerization of aniline and the formation of supramolecular polyaniline structures
Authors: Sapurina Irina , Stejskal Jaroslav
Published: October 2008

Polyaniline is one of the most important conducting and responsive polymers. A molecular mechanism for the oxidation of aniline is proposed. This mechanism explains the specific features of aniline oligomerization and polymerization in various acidity ranges. The formation of polyaniline precipitates, colloids and thin films is reviewed and discussed on the basis of the chemistry of aniline oxidation. The generation of nanostructures, i.e. granules, nanotubes, nanowires and microspheres, is also considered. Oligomers containing phenazine constitutional units play an important role in self‐assembly to form templates. Polyaniline chains then grow from these templates and produce the various individual morphologies. Copyright © 2008 Society of Chemical Industry
Preparation and characterization of styrene/styryl–polyhedral oligomeric silsesquioxane hybrid copolymers
Authors: Zhang He‐xin , Lee Ho‐young , Shin Young‐jun , Yoon Keun‐byoung , Noh Seok‐Kyun , Lee Dong‐ho
Published: October 2008

BACKGROUND: Organic–inorganic nanocomposites were prepared by copolymerization of various monomers and polyhedral oligomeric silsesquioxane (POSS) derivatives. Preliminary results showed that styrene/styryl–POSS copolymers could be obtained using CpTiCl3 catalyst. In the work reported here, the copolymerization of styrene and styryl‐substituted POSS was studied in detail for a more effective catalyst, Cp*TiCl3.

RESULTS: The glass transition temperature (Tg) of the copolymers prepared increased with increasing POSS content. The degradation temperature (Td) of the copolymers was 60 °C higher than that of syndiotactic polystyrene under nitrogen. Although the thermal properties were improved by incorporation of POSS, the catalytic activity decreased with POSS content. The racemic triad and syndiotactic index of the copolymers decreased with increasing POSS content. Gel permeation chromatograms of the copolymers exhibited multimodal distribution due to the presence of multi‐active centres, which were formed by interaction of Ti with the POSS siloxane linkage.

CONCLUSION: With the incorporation of POSS, the thermal properties of polystyrene were improved. The styrene/styryl–POSS copolymers are formed through the various active sites arising from the interactions of Ti with POSS. Copyright © 2008 Society of Chemical Industry
Modelling the Low‐Pressure N2O2 Plasma Afterglow to Determine the Kinetic Mechanisms Controlling the UV Emission Intensity and Its Spatial Distribution for Achieving an Efficient Sterilization Process
Authors: Kutasi Kinga , Saoudi Bachir , Pintassilgo Carlos D. , Loureiro Jorge , Moisan Michel
Published: October 2008

The flowing afterglow of a N2O2 microwave discharge intended to provide intense and spatially uniform UV emission for an efficient inactivation of bacterial spores is modelled with a 3‐D hydrodynamic model leading to the spatial density distribution of the species in the reactor. The agreement of the calculated densities of the NO(A) and NO(B) UV emitting species with the corresponding measured emission intensities strongly supports the choice of the kinetic reactions retained in the model. In that respect, the specific contribution of N and O atoms to the spatial distribution of the NO(A) density (generating the NOγ system) in the late afterglow is, for the first time, brought into relief.

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Methane Oligomerization in a Dielectric Barrier Discharge at Atmospheric Pressure
Authors: Scarduelli Giorgina , Guella Graziano , Mancini Ines , Dilecce Giorgio , De Benedictis Santolo , Tosi Paolo
Published: October 2008

The conversion of methane into more valuable higher hydrocarbons has been more and more fascinating for both the industry and the scientific community. Recently, the direct conversion of methane by using various plasma technologies has received particular attention. This work reports on the formation of a liquid deposit during the plasma treatment of methane mixtures in a coaxial cylindrical dielectric barrier discharge reactor at atmospheric pressure. In order to investigate its nature, the liquid deposit has been analyzed by spectroscopic and mass spectrometric techniques. The material consists of a mixture of hydrocarbons, the most represented moiety being the gem‐dimethyl group CC(CH3)2C.

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A Novel Insensitive High Explosive 3,4‐Bis (Aminofurazano) Furoxan
Authors: Wang Jun , Li Jinshan , Liang Qinqin , Huang Yigang , Dong Haishan
Published: October 2008

A novel insensitive high explosive 3,4‐bis (aminofurazano) furoxan (BAFF) was prepared using 3‐amino‐4‐acylchloroximinofurazan (ACOF) as a precursor. The molecular and crystal structures of BAFF were characterized by IR, MS, 1H NMR, 13C NMR, elemental analysis, and single crystal X‐ray diffraction. The single crystal structure of BAFF recrystallized from water is monoclinic, space group P 21/c, and ρc=1.745 g cm−3, and that recrystallized from ethanol is triclinic, space group P 1, and ρc=1.737 g cm−3. BAFF has multiple crystal forms. The calculated detonation velocity by BKW code is 8100 m s−1 (ρ=1.795 g cm−3, theoretical density calculated by quantum chemistry) and the experimental value is 7177 m s−1 (ρ=1.530 g cm−3, charge density). The tested values of impact, friction, and electrostatic spark sensitivity show that BAFF is insensitive.
Lithographically patterned nanowire electrodeposition
Authors: Xiang Chengxiang , Thompson Michael A. , Yang Fan , Menke Erik J. , Yang Li‐Mei C. , Penner Reginald M.
Published: October 2008

The cover picture of this issue of physica status solidi (c) has been taken from the article [1]. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Test substance characterization for the EPA: what you've always wanted to know but were afraid to ask
Authors: Barta William , Lee Carol , Oster Maryanne , White Tammy
Published: October 2008

The Society of Quality Assurance (SQA) GLP Specialty Section, a member of the SQA Regulatory Forum, is a group of participants from the regulated community which provides insight and guidance to our membership and the regulated community. The Specialty Section has encountered several participants who want to know what types of information and data are needed during an inspection by the US EPA's Office of Enforcement and Compliance Assurance (OECA). The OECA is responsible for monitoring studies submitted to the Office of Pesticide Programs in support of pesticide registrations as defined under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA). All submitted studies are to be conducted according to the FIFRA US Good Laboratory Practice Standards (GLPS). The GLPS contain specific language concerning the characterization of test, control and reference substances used in these studies. This article clarifies those requirements and provides perspective on the EPA expectations on meeting those requirements. The topics of discussion include:

regulatory requirements

responsibilities of the testing facility management, study director, Quality Assurance Unit and the sponsor

preparing for an inspection

overview of data to be made available at the time of inspection

composition of a Certificate of Analysis.

Copyright © 2008 John Wiley & Sons, Ltd.
GSH‐dependent iNOS and HO‐1 mediated apoptosis of human Jurkat cells induced by nickel(II)
Authors: Zhang Dongmei , Shen Jie , Wang Cuicui , Zhang Xin , Chen Junhui
Published: October 2008

The molecular mechanisms by which nickel compounds cause immune cytotoxicity are far from understood. Our preliminary data suggested that nickel(II) induced apoptosis in Jurkat cells by mitochondrial pathway, specifically via mitochondrial membrane potential dissipation and antiapoptotic gene bcl‐2 down‐regulation. The main goal of this study was to further investigate the toxicity of nickel, especially the induction of reactive oxygen species (ROS) on immune cells, which finally induced apoptosis. Nickel was found to induce glutathione (GSH) depletion in a dose‐ and time‐dependent manner. When Jurkat cells were preincubated with antioxidant N‐acetylcysteine (NAC), apoptosis was inhibited distinctly, which suggested that ROS played an initial role in nickel immune toxicity. Heme oxygenase‐1 (HO‐1) and Nitric oxide (NO) which may play an important role in regulatory and protective processes in cells were assayed upon nickel treatment. A significant increase in HO‐1 mRNA levels was detected in nickel treated cells. We confirmed that reduction of Nitrate levels in Jurkat cells was due to down‐regulation of inducible nitric oxide synthase (iNOS), not endothelial nitric oxide synthase (eNOS). Expression changes of HO‐1 and iNOS were markedly blocked when Jurkat cells were preincubated with NAC, suggesting that ROS resulted in HO‐1 and iNOS dysfunction in Jurkat cells. We supposed that the immune toxicity of nickel(II) was mainly due to GSH depletion and finally led to apoptosis, probably via changing the expression levels of HO‐1 and iNOS in human T lymphocytes. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2009.
Ultrasound-Assisted Percutaneous Trigger Finger Release: Is it Safe?
Authors: Paulius Karina L. , Maguina Pirko
Published: October 2008

Trigger fingers can be treated by open or percutaneous division of the A1 pulley. The open approach allows for visualization of the pulley, the tendon, and the adjacent neurovascular bundles. The percutaneous trigger finger release (PTFR) lacks an incision and is thought to lead to a quicker recovery, but the safety and efficacy of this blind procedure are often questioned. Ultrasound imaging has recently been introduced as an adjunct for guiding the needle during percutaneous trigger finger release. This study was designed to evaluate the safety and efficacy of needle trigger finger release with added ultrasound imaging. Eighteen fresh cadaver A1 pulleys were divided percutaneously and then evaluated by converting to an open technique and examining the pulleys, the tendons, and the neurovascular bundles. This study's ultrasound images demonstrated repeated puncture of the tendon sheath and of the neurovascular bundle during PTFR. The subsequent dissection revealed three out of 18 tendons with visible lacerations and 15 out of 18 A1 pulleys with incomplete division. We concluded that ultrasound-guided PTFR can be complicated by flexor tendon lacerations, potential injury to neurovascular bundles, and incomplete division of the A1 pulleys. While the clinical significance of these findings is unclear to us, it does raise questions regarding the safety and efficacy of percutaneous trigger finger release, even when adding ultrasound guidance.
The Synthesis of Oleic Acid Polyglycol Ester Catalyzed by Solid Super Acid
Authors: Luo Xiao‐min , Ren Long‐fang , Zhang Xiao‐lei , Qiang Tao‐tao
Published: October 2008

A SO42−/ZrO2 super acid was prepared and the effect of different kinds of catalysts on the esterification reaction reviewed. The results showed that the SO42−/ZrO2 super acid had higher catalytic activity and reactive selectivity in the synthesis of oleic acid polyglycol ester. Under optimum conditions the product was a monoester and the rate of production was more than 90%. The reaction product was characterized.
Proximal femoral osteotomies in children using the Richards hip screw: Techniques, outcome and subsequent removal
Authors: Webb James A. , Almaiyah Mohammed , McVie Jim , Montgomery Richard J.
Published: October 2008

Introduction

We investigated the clinical and radiological outcome of proximal femoral osteotomies in children using the Richards hip screw. We also describe previously unreported techniques used in the insertion of the screw to aid satisfactory correction of the neck shaft angle and medialisation.

Methods

Seventy-two children undergoing 81 proximal femoral osteotomies under the care of the senior author over a 10-year period were reviewed.

Results

For the primary procedure, there was an overall complication rate of 5%. This included two (2.5%) cases requiring re-operation. There were no fractures and no long-term complications. For subsequent removal of the metalwork, the complication rate was 5%, with a re-operation rate of 1%.

Conclusion

We conclude that the Richards hip screw is a safe, atraumatic and easy-to-use method of fixation for proximal femoral osteotomies in children, with lower complication.
Differential Plasma Glycoproteome of p19ARF Skin Cancer Mouse Model Using the Corra Label-Free LC-MS Proteomics Platform
Authors: Letarte Simon , Brusniak Mi-Youn , Campbell David , Eddes James , Kemp Christopher J. , Lau Hollis , Mueller Lukas , Schmidt Alexander , Shannon Paul , Kelly-Spratt Karen S. , Vitek Olga , Zhang Hui , Aebersold Ruedi , Watts Julian D.
Published: October 2008

Introduction

A proof-of-concept demonstration of the use of label-free quantitative glycoproteomics for biomarker discovery workflow is presented in this paper, using a mouse model for skin cancer as an example.

Materials and Methods

Blood plasma was collected from ten control mice and ten mice having a mutation in the p19ARFgene, conferring them high propensity to develop skin cancer after carcinogen exposure. We enriched for N-glycosylated plasma proteins, ultimately generating deglycosylated forms of the tryptic peptides for liquid chromatography mass spectrometry (LC-MS) analyses. LC-MS runs for each sample were then performed with a view to identifying proteins that were differentially abundant between the two mouse populations. We then used a recently developed computational framework, Corra, to perform peak picking and alignment, and to compute the statistical significance of any observed changes in individual peptide abundances. Once determined, the most discriminating peptide features were then fragmented and identified by tandem mass spectrometry with the use of inclusion lists.

Results and Discussions

We assessed the identified proteins to see if there were sets of proteins indicative of specific biological processes that correlate with the presence of disease, and specifically cancer, according to their functional annotations. As expected for such sick animals, many of the proteins identified were related to host immune response. However, a significant number of proteins are also directly associated with processes linked to cancer development, including proteins related to the cell cycle, localization, transport, and cell death. Additional analysis of the same samples in profiling mode, and in triplicate, confirmed that replicate MS analysis of the same plasma sample generated less variation than that observed between plasma samples from different individuals, demonstrating that the reproducibility of the LC-MS platform was sufficient for this application.

Conclusion

These results thus show that an LC-MS-based workflow can be a useful tool for the generation of candidate proteins of interest as part of a disease biomarker discovery effort.
Homogenization of periodic semilinear parabolic degenerate PDEs
Authors: Sow A.B. , Rhodes R. , Pardoux É.
Published: September 2008

In this paper a second order semilinear parabolic PDE with rapidly oscillating coefficients is homogenized. The novelty of our result lies in the fact that we allow the second order part of the differential operator to be degenerate in some part of\mathbf{R}^{d}.

Our fully probabilistic method is based on the deep connection between PDEs and BSDEs and the weak convergence of a class of diffusion processes.
Pulsating traveling waves in the singular limit of a reaction–diffusion system in solid combustion
Authors: Monneau R. , Weiss G.S.
Published: September 2008

We consider a coupled system of parabolic/ODE equations describing solid combustion. For a given rescaling of the reaction term (the high activation energy limit), we show that the limit solution solves a free boundary problem which is to our knowledge new.

In the time-increasing case, the limit coincides with the Stefan problem with spatially inhomogeneous coefficients. In general it is a parabolic equation with a memory term.

In the first part of our paper we give a characterization of the limit problem in one space dimension. In the second part of the paper, we construct a family of pulsating traveling waves for the limit one phase Stefan problem with periodic coefficients. This corresponds to the assumption of periodic initial concentration of reactant.
A potential model for studying the plasticity and reprogramming of human epidermal stem cells through preimplantation blastocyst microinjection
Authors: Jiang Ruzhang , Huang Bing , Jin Chenjin , Song Ge , Zhong Xiufeng , Yuan Jing , Xiang Peng , He Yuan , Liu Bingqian , Sun Xuerong , Zhang Yuehong , Ge Jian
Published: October 2008

Microinjection of adult stem cells (ASCs) into blastocysts provides a classic model for studying ASC plasticity. To explore the molecular mechanisms that govern the reprogramming of ASCs, we evaluated the experimental model through microinjection of human epidermal stem cells (hEpiSCs) into mouse blastocysts. Mouse blastocysts underwent regular embryogenesis after microinjection of allogeneic cells, confirmed by morphological observation and embryo cell counting. hEpiSCs survive and integrate into mouse embryos, by monitoring the migration of injected cells at 2, 4, 12, 16 and 24 h. In this xenogeneic system, hEpiSCs could be reprogrammed within 24 h, as evidenced by the silencing of CK15 and Integrinβ1 gene expression, without activation of Oct4 and Nanog. Microinjection of hEpiSCs into mouse blastocysts provides an efficient model for studying the molecular mechanisms of their plasticity. Moreover, the possibility of inducing pluripotent stem cells without transgenes or viruses can be entertained.
Response regulator YycF essential for bacterial growth: X‐ray crystal structure of the DNA‐binding domain and its PhoB‐like DNA recognition motif
Authors: Okajima Toshihide , Doi Akihiro , Okada Ario , Gotoh Yasuhiro , Tanizawa Katsuyuki , Utsumi Ryutaro
Published: September 2008

A response regulator YycF and its cognate sensor kinase YycG constitute the two‐component signal transduction system essential for growth of Gram‐positive bacteria with a low GC content. We have determined the X‐ray crystal structure of the effector domain of Bacillus subtilis YycF involved in DNA binding. The structure, containing a winged helix‐turn‐helix motif, was found to be very similar to that of the response regulator PhoB from Escherichia coli. Specific binding of YycF to the PhoB‐regulated alkaline phosphatase promoter was also demonstrated.
Kinetic characterization of l‐[3H]glutamate uptake inhibition and increase oxidative damage induced by glutaric acid in striatal synaptosomes of rats
Authors: Magni Danieli Valnes , Furian Ana Flávia , Oliveira Mauro Schneider , Souza Mauren Assis , Lunardi Fabiane , Ferreira Juliano , Mello Carlos Fernando , Royes Luiz Fernando Freire , Fighera Michele Rechia
Published: September 2008

Glutaric acidemia type I (GA‐I) is an inherited metabolic disease characterized by accumulation of glutaric acid (GA) and striatal degeneration. Although growing evidence suggests that excitotoxicity and oxidative stress play central role in the neuropathogenesis of this disease, mechanism underlying striatal damage in this disorder is not well established. Thus, we decided to investigate the in vitro effects of GA 10 nM (a low concentration that can be present initial development this disorder) on l‐[3H]glutamate uptake and reactive oxygen species (ROS) generation in synaptosomes from striatum of rats. GA reduced l‐[3H]glutamate uptake in synaptosomes from 1 up to 30 min after its addition. Furthermore, we also provided some evidence that GA competes with the glutamate transporter inhibitor l‐trans‐pyrrolidine‐2,4‐dicarboxylate (PDC), suggesting a possible interaction of GA with glutamate transporters on synaptosomes. Moreover, GA produced a significant decrease in the VMAX of l‐[3H]glutamate uptake, but did not affect the KD value. Although the GA did not show oxidant activity per se, it increased the ROS generation in striatal synaptosomes. To evaluate the involvement of reactive species generation in the GA‐induced l‐[3H]glutamate uptake inhibition, trolox (0.3, 0.6 and 6 μM) was added on the incubation medium. Statistical analysis showed that trolox did not decrease inhibition of GA‐induced l‐[3H]glutamate uptake, but decreased GA‐induced reactive species formation in striatal synaptosomes (1, 3, 5, 10, 15 and 30 min), suggesting that ROS generation appears to occur secondarily to glutamatergic overstimulation in this model of organic acidemia. Since GA induced DCFH oxidation increase, we evaluate the involvement of glutamate receptor antagonists in oxidative stress, showing that CNQX, but not MK‐801, decreased the DCFH oxidation increase in striatal synaptosomes. Furthermore, the results presented in this report suggest that excitotoxicity elicited by low concentration of GA, could be in part by maintaining this excitatory neurotransmitter in the synaptic cleft by non‐competitive inhibition of glutamate uptake. Thus the present data may explain, at least partly, initial striatal damage at birth, as evidenced by acute bilateral destruction of caudate and putamen observed in children with GA‐I.