bluuebunny/crossref_metadata_2025 huggingface dataset:
Potential distributions around a moving test charge in quantum plasmas
Authors: Ali S. , Shukla P. K.
Published: October 2006

By using the dielectric response function of quantum electron plasmas, potential distributions around a moving test charge are calculated. The near-field potential follows the modified Debye-Hückel potential, while the far-field potential turns out to be oscillatory. Both the Debye-Hückel and wake potentials strongly depend on the Fermi energy and the electron quantum correlation strength. The relevance of the present investigation to semiconductor plasmas is discussed.
Design and development of a large range linear encoder with subnanometer resolution
Authors: Huang Yanan , Menq Chia-Hsiang
Published: October 2006

This article presents the design and development of a large range linear encoder system, in which a displacement transducer is controlled to achieve a stable oscillation over the moving reference grating so as to modulate the motion being measured. Utilizing a special demodulating signal and according to linear control theory, a phase-locked feedback loop is designed to extract motion from the transducer’s measurement signal. The measurement dynamics, limited by the sinusoidal nonlinearity in the loop, is analyzed. A method that compensates the effect of the reference grating’s geometric error and that improves the measurement accuracy is also proposed. A prototype system, using an optical pickup unit as the displacement transducer and a holographic grating as the reference, is implemented. The performance of the system is tested to verify its resolution, bandwidth, and accuracy. A measurement resolution of 0.06nm rms with 140Hz bandwidth is achieved, and the measurement range is only limited by the size of the reference grating employed. All the experimental results confirm the theoretical analysis. Calibration of the system shows that after compensation the measurement accuracy is in the nanometer order.
Development of a low energy ion source for ROSINA ion mode calibration
Authors: Rubin Martin , Altwegg Kathrin , Jäckel Annette , Balsiger Hans
Published: October 2006

The European Rosetta mission on its way to comet 67P/Churyumov-Gerasimenko will remain for more than a year in the close vicinity (1 km) of the comet. The two ROSINA mass spectrometers on board Rosetta are designed to analyze the neutral and ionized volatile components of the cometary coma. However, the relative velocity between the comet and the spacecraft will be minimal and also the velocity of the outgassing particles is below 1km∕s. This combination leads to very low ion energies in the surrounding plasma of the comet, typically below 20eV. Additionally, the spacecraft may charge up to a few volts in this environment. In order to simulate such plasma and to calibrate the mass spectrometers, a source for ions with very low energies had to be developed for the use in the laboratory together with the different gases expected at the comet. In this paper we present the design of this ion source and we discuss the physical parameters of the ion beam like sensitivity, energy distribution, and beam shape. Finally, we show the first ion measurements that have been performed together with one of the two mass spectrometers.
Mesoscale simulation of polymer reaction equilibrium: Combining dissipative particle dynamics with reaction ensemble Monte Carlo. I. Polydispersed polymer systems
Authors: Lísal Martin , Brennan John K. , Smith William R.
Published: October 2006

We present a mesoscale simulation technique, called the reaction ensemble dissipative particle dynamics (RxDPD) method, for studying reaction equilibrium of polymer systems. The RxDPD method combines elements of dissipative particle dynamics (DPD) and reaction ensemble Monte Carlo (RxMC), allowing for the determination of both static and dynamical properties of a polymer system. The RxDPD method is demonstrated by considering several simple polydispersed homopolymer systems. RxDPD can be used to predict the polydispersity due to various effects, including solvents, additives, temperature, pressure, shear, and confinement. Extensions of the method to other polymer systems are straightforward, including grafted, cross-linked polymers, and block copolymers. To simulate polydispersity, the system contains full polymer chains and a single fractional polymer chain, i.e., a polymer chain with a single fractional DPD particle. The fractional particle is coupled to the system via a coupling parameter that varies between zero (no interaction between the fractional particle and the other particles in the system) and one (full interaction between the fractional particle and the other particles in the system). The time evolution of the system is governed by the DPD equations of motion, accompanied by changes in the coupling parameter. The coupling-parameter changes are either accepted with a probability derived from the grand canonical partition function or governed by an equation of motion derived from the extended Lagrangian. The coupling-parameter changes mimic forward and reverse reaction steps, as in RxMC simulations.
Effects of bottom electrode conditions on ferroelectric properties of SrBi2Ta2O9 thin films
Authors: Ashikaga Kinya , Inomata Daisuke , Igarashi Yasushi , Takaya Koji , Kanehara Takao , Kumagai Tomoya , Koiwa Ichiro
Published: October 2006

The effect of adhesion layers under the bottom electrodes on ferroelectric characteristics of SrBi2Ta2O9 (SBT) thin films synthesized by sol-gel method was investigated. The remanent polarization (2Pr) of SBT films was found to be smaller for the tantalum oxide (TaOx) adhesion layer than for the titanium oxide (TiOx) adhesion layer, whereas the coercive voltage (2Vc) was larger for the TaOx adhesion layer than for the TiOx adhesion layer. The difference was due to a larger c-axis distribution of crystals in the SBT film on Pt with the TaOx layer than with the TiOx layer. Moreover, the imprint characteristics of SBT capacitors on the TaOx layer were better than those on the TiOx layer because the 2Vc in SBT capacitors was larger for the TaOx layer than for the TiOx layer, and the polarization stability against the hysteresis shift was better for the TaOx layer than for the TiOx layer.
Hydrogen bridging in the compounds X2H (X=Al,Si,P,S)
Authors: Owens Zachary T. , Larkin Joseph D. , Schaefer Henry F.
Published: October 2006

X 2 H hydrides (X=Al, Si, P, and S) have been investigated using coupled cluster theory with single, double, and triple excitations, the latter incorporated as a perturbative correction [CCSD(T)]. These were performed utilizing a series of correlation-consistent basis sets augmented with diffuse functions (aug-cc-pVXZ, X=D, T, and Q). Al2H and Si2H are determined to have H-bridged C2v structures in their ground states: the Al2H ground state is of B12 symmetry with an Al–H–Al angle of 87.6°, and the Si2H ground state is of A12 symmetry with a Si–H–Si angle of 79.8°. However, P2H and S2H have nonbridged, bent Cs structures: the P2H ground state is of A′2 symmetry with a P–P–H angle of 97.0°, and the S2H ground state is of A′2 symmetry with a S–S–H angle of 93.2°. Ground state geometries, vibrational frequencies, and electron affinities have been computed at all levels of theory. Our CCSD(T)/aug-cc-pVQZ adiabatic electron affinity of 2.34eV for the Si2H radical is in excellent agreement with the photoelectron spectroscopy experiments of Xu et al. [J. Chem. Phys. 108, 7645 (1998)], where the electron affinity was determined to be 2.31±0.01eV.
Thermal conduction in nanocrystalline diamond films: Effects of the grain boundary scattering and nitrogen doping
Authors: Liu W. L. , Shamsa M. , Calizo I. , Balandin A. A. , Ralchenko V. , Popovich A. , Saveliev A.
Published: October 2006

The authors investigated thermal conductivity (K) in nanocrystalline diamond (NCD) films on silicon using the 3ω and laser flash techniques. The K temperature dependence has been studied for the undoped and nitrogen-doped NCD films for T=80–400K and compared with that in microcrystalline diamond (MCD) films. The effects of phonon scattering from the grain boundaries and film interfaces on thermal conduction have been studied using three different models. For NCD the room temperature K is 0.1–0.16W∕cmK and decreases with nitrogen doping. The K temperature dependence in NCD is different from that in MCD films and can be adequately described by the phonon-hopping model.
Micromachined silicon plates for sensing molecular interactions
Authors: Carlen Edwin T. , Weinberg Marc S. , Dubé Christopher E. , Zapata Angela M. , Borenstein Jeffrey T.
Published: October 2006

A micromachined surface stress sensor based on a thin suspended crystalline silicon circular plate measures differential surface stress changes associated with vapor phase chemisorption of an alkanethiol self-assembled monolayer. The isolated face of the suspended silicon plate serves as the sensing surface treated with a receptor layer sensitive to a target molecule, in this case Au(111). Chemisorption of an alkanethiol on the gold coated silicon surfaces results in plate bending. Plate displacements, measured with a phase scanning interferometer, indicate a differential surface stress change Δσs=−0.72±0.02Nm−1 for 1-dodecanethiol.
Modelling Nitrogen Deposition on a Local Scale—A Review of the Current State of the Art
Authors: Hertel Ole , Skjøth Carsten Ambelas , Løfstrøm Per , Geels Camilla , Frohn Lise Marie , Ellermann Thomas , Madsen Peter Vangsbo
Published: October 2006

Abstract. Local ammonia emissions from agricultural activities are often associated with high nitrogen deposition in the close vicinity of the sources. High nitrogen (N) inputs may significantly affect the local ecosystems. Over a longer term, high loads may change the composition of the ecosystems, leading to a general decrease in local biodiversity. In Europe there is currently a significant focus on the impact of atmospheric N load on local ecosystems among environmental managers and policy makers. Model tools designed for application in N deposition assessment and aimed for use in the regulation of anthropogenic nitrogen emissions are, therefore, under development in many European countries. The aim of this paper is to present a review of the current understanding and modelling parameterizations of atmospheric N deposition. A special focus is on the development of operational tools for use in environmental assessment and regulation related to agricultural ammonia emissions. For the often large number of environmental impact assessments needed to be carried out by local environmental managers there is, furthermore, a need for simple and fast model systems. These systems must capture the most important aspects of dispersion and deposition of N in the nearby environment of farms with animal production. The paper includes a discussion on the demands on the models applied in environmental assessment and regulation and how these demands are fulfilled in current state-of-the-art models.
Modeling dual pathways for the metazoan spindle assembly checkpoint
Authors: Sear Richard P. , Howard Martin
Published: October 2006

Using computational modeling, we investigate mechanisms of signal transduction. We focus on the spindle assembly checkpoint, where a single unattached kinetochore is able to signal to prevent cell cycle progression. The inhibitory signal switches off rapidly once spindle microtubules have attached to all kinetochores. This requirement tightly constrains the possible mechanisms. Here we investigate two possible mechanisms for spindle checkpoint operation in metazoan cells, both supported by recent experiments. The first involves the free diffusion and sequestration of cell cycle regulators. This mechanism is severely constrained both by experimental fluorescence recovery data and by the large volumes involved in open mitosis in metazoan cells. By using a simple mathematical analysis and computer simulation, we find that this mechanism can generate the inhibition found in experiment but likely requires a two-stage signal amplification cascade. The second mechanism involves spatial gradients of a short-lived inhibitory signal that propagates first by diffusion but then primarily by active transport along spindle microtubules. We propose that both mechanisms may be operative in the metazoan spindle assembly checkpoint, with either able to trigger anaphase onset even without support from the other pathway.
Single-step electronic detection of femtomolar DNA by target-induced strand displacement in an electrode-bound duplex
Authors: Xiao Yi , Lubin Arica A. , Baker Brian R. , Plaxco Kevin W. , Heeger Alan J.
Published: October 2006

We report a signal-on, electronic DNA (E-DNA) sensor that is label-free and achieves a subpicomolar detection limit. The sensor, which is based on a target-induced strand displacement mechanism, is composed of a “capture probe” attached by its 5′ terminus to a gold electrode and a 5′ methylene blue-modified “signaling probe” that is complementary at both its 3′ and 5′ termini to the capture probe. In the absence of target, hybridization between the capture and signaling probes minimizes contact between the methylene blue and electrode surface, limiting the observed redox current. Target hybridization displaces the 5′ end of the signaling probe, generating a short, flexible single-stranded DNA element and producing up to a 7-fold increase in redox current. The observed signal gain is sufficient to achieve a demonstrated (not extrapolated) detection limit of 400 fM, which is among the best reported for single-step electronic DNA detection. Moreover, because sensor fabrication is straightforward, the approach appears to provide a ready alternative to the more cumbersome femtomolar electrochemical assays described to date.
A Role for Clathrin in Reassembly of the Golgi Apparatus
Authors: Radulescu Andreea E. , Siddhanta Anirban , Shields Dennis
Published: October 2006

The Golgi apparatus is a highly dynamic organelle whose organization is maintained by a proteinaceous matrix, cytoskeletal components, and inositol phospholipids. In mammalian cells, disassembly of the organelle occurs reversibly at the onset of mitosis and irreversibly during apoptosis. Several pharmacological agents including nocodazole, brefeldin A (BFA), and primary alcohols (1-butanol) induce reversible fragmentation of the Golgi apparatus. To dissect the mechanism of Golgi reassembly, rat NRK and GH3 cells were treated with 1-butanol, BFA, or nocodazole. During washout of 1-butanol, clathrin, a ubiquitous coat protein implicated in vesicle traffic at the trans-Golgi network and plasma membrane, and abundant clathrin coated vesicles were recruited to the region of nascent Golgi cisternae. Knockdown of endogenous clathrin heavy chain showed that the Golgi apparatus failed to reform efficiently after BFA or 1-butanol removal. Instead, upon 1-butanol washout, it maintained a compact, tight morphology. Our results suggest that clathrin is required to reassemble fragmented Golgi elements. In addition, we show that after butanol treatment the Golgi apparatus reforms via an initial compact intermediate structure that is subsequently remodeled into the characteristic interphase lace-like morphology and that reassembly requires clathrin.
Hepatocyte Growth Factor-induced Ras Activation Requires ERM Proteins Linked to Both CD44v6 and F-Actin
Authors: Orian-Rousseau Véronique , Morrison Helen , Matzke Alexandra , Kastilan Thor , Pace Giuseppina , Herrlich Peter , Ponta Helmut
Published: October 2006

In several types of cells, the activation of the receptor tyrosine kinase c-Met by its ligand hepatocyte growth factor (HGF) requires the coreceptor CD44v6. The CD44 extracellular domain is necessary for c-Met autophosphorylation, whereas the intracellular domain is required for signal transduction. We have already shown that the CD44 cytoplasmic tail recruits ezrin, radixin and moesin (ERM) proteins to the complex of CD44v6, c-Met, and HGF. We have now defined the function of the ERM proteins and the step they promote in the signaling cascade. The association of ERM proteins to the coreceptor is absolutely required to mediate the HGF-dependent activation of Ras by the guanine nucleotide exchange factor Sos. The ERM proteins need, in addition, to be linked to the actin cytoskeleton to catalyze the activation of Ras. Thus, we describe here a new function of the cytoskeleton. It is part of a “signalosome” complex that organizes the activation of Ras by Sos. So far the cytoskeleton has mainly been identified as a “responder” to signal transduction. Here, we show now that F-actin acts as an “inducer” that actively organizes the signaling cascade.
Evolution of the complementary sex-determination gene of honey bees: Balancing selection and trans-species polymorphisms
Authors: Cho Soochin , Huang Zachary Y. , Green Daniel R. , Smith Deborah R. , Zhang Jianzhi
Published: October 2006

The mechanism of sex determination varies substantively among evolutionary lineages. One important mode of genetic sex determination is haplodiploidy, which is used by ∼20% of all animal species, including >200,000 species of the entire insect order Hymenoptera. In the honey bee Apis mellifera, a hymenopteran model organism, females are heterozygous at the csd (complementary sex determination) locus, whereas males are hemizygous (from unfertilized eggs). Fertilized homozygotes develop into sterile males that are eaten before maturity. Because homozygotes have zero fitness and because common alleles are more likely than rare ones to form homozygotes, csd should be subject to strong overdominant selection and negative frequency-dependent selection. Under these selective forces, together known as balancing selection, csd is expected to exhibit a high degree of intraspecific polymorphism, with long-lived alleles that may be even older than the species. Here we sequence the csd genes as well as randomly selected neutral genomic regions from individuals of three closely related species, A. mellifera, Apis cerana, and Apis dorsata. The polymorphic level is approximately seven times higher in csd than in the neutral regions. Gene genealogies reveal trans-species polymorphisms at csd but not at any neutral regions. Consistent with the prediction of rare-allele advantage, nonsynonymous mutations are found to be positively selected in csd only in early stages after their appearances. Surprisingly, three different hypervariable repetitive regions in csd are present in the three species, suggesting variable mechanisms underlying allelic specificities. Our results provide a definitive demonstration of balancing selection acting at the honey bee csd gene, offer insights into the molecular determinants of csd allelic specificities, and help avoid homozygosity in bee breeding.
Phylogenomic analysis reveals bees and wasps (Hymenoptera) at the base of the radiation of Holometabolous insects
Authors: Savard Joël , Tautz Diethard , Richards Stephen , Weinstock George M. , Gibbs Richard A. , Werren John H. , Tettelin Hervé , Lercher Martin J.
Published: October 2006

Comparative studies require knowledge of the evolutionary relationships between taxa. However, neither morphological nor paleontological data have been able to unequivocally resolve the major groups of holometabolous insects so far. Here, we utilize emerging genome projects to assemble and analyze a data set of 185 nuclear genes, resulting in a fully resolved phylogeny of the major insect model species. Contrary to the most widely accepted phylogenetic hypothesis, bees and wasps (Hymenoptera) are basal to the other major holometabolous orders, beetles (Coleoptera), moths (Lepidoptera), and flies (Diptera). We validate our results by meticulous examination of potential confounding factors. Phylogenomic approaches are thus able to resolve long-standing questions about the phylogeny of insects.
A discussion of individual variability, in activity‐based interventions, using the niche concept
Authors: Dada S. , Granlund M. , Alant E.
Published: October 2006

Background  Activity‐based intervention has been defined as a child‐directed, transactional approach that uses logically occurring antecedents and consequences to develop functional and generative skills by embedding intervention of children’s individual goals and objectives in routine, planned or child‐initiated activities. In this approach, clear goals and objectives that are functional and embedded in a play activities or routines are developed. The teacher mediates the child’s environment to facilitate learning with the child directing the teacher on the pace, duration spent on the objective. Learning and development in this framework occur through both a carefully planned environment and adult facilitation. Progress made by a child using this approach focuses on observational data that describe if the child is able to respond in functional and generative ways. While activity‐based interventions are usually provided for a group of children, progress is measured by describing individual children’s responses. Individual variations in the children’s progress, despite exposure to the same interventions are an area that is seldom discussed. This article aims to explore the niche concept and its application to explaining this variation between individuals.

Methods  Four children participated in this single‐subject, multiple‐probe study across four participants. A 3‐week long activity‐based aided language stimulation programme was developed. The effect of the programme was determined by describing the individual participants understanding of the 24 targeted vocabulary items.

Results  The results of the activity‐based language programme are presented and the variability among the participants is discussed using the niche concept. The role of the niche concept in individual development is described and the implications thereof are discussed.

Conclusions  Finally, activity‐based intervention research is placed in a systems perspective and possible outcome measures of this intervention are discussed from a multidimensional ecological perspective.
Reduced expression of C1q-mRNA in monocytes from patients with systemic lupus erythematosus
Authors: Moosig F , Damm F , Knorr-Spahr A , Ritgen M , Zeuner R A , Kneba M , Ernst M , Schröder J O
Published: October 2006

Inherited C1q deficiency is associated strongly with the development of systemic lupus erythematosus (SLE). The aim of our study was to evaluate the ability of monocytes from SLE patients without inherited C1q deficiency to up-regulate C1q-mRNA upon stimulation. Furthermore, we wanted to elucidate the physiological stimulus for up-regulation of C1q-mRNA. Peripheral blood mononuclear cell (PBMC)-derived monocytes from 10 SLE patients, 10 patients with rheumatoid arthritis (RA) and 10 healthy controls (HC) were stimulated with dexamethasone (DXM), interferon-gamma or both. Additionally, purified monocytes from HC were stimulated with interleukin (IL)-10. C1q-mRNA expression was measured by quantitative reverse transcription–polymerase chain reaction (RT–PCR). C1q protein was detected using the standard alkaline phosphatase/anti-alkaline phosphatase (APAAP) technique. SLE monocytes were significantly less able to up-regulate C1q-mRNA when compared to RA or HC. IL-10 was identified as an important stimulus for C1q synthesis. In SLE patients there is a significant functional impairment of monocytes to synthesize C1q upon stimulation. As C1q is linked to the process of recognition and removal of apoptotic cells, this relative C1q deficiency is likely to contribute to the reduced phagocytosis of apoptotic material observed in SLE and thereby might be a central pathogenetic factor.
The major surface‐metalloprotease of the parasitic protozoan, Leishmania, protects against antimicrobial peptide‐induced apoptotic killing
Authors: Kulkarni Manjusha M. , McMaster W. Robert , Kamysz Elzbieta , Kamysz Wojciech , Engman David M. , McGwire Bradford S.
Published: October 2006

Human infection by the vector‐borne protozoan Leishmania is responsible for substantial worldwide morbidity and mortality. The surface‐metalloprotease (leishmanolysin) of Leishmania is a virulence factor which contributes to a variety of functions including evasion of complement‐mediated parasite‐killing and host intramacrophage survival. We tested the hypothesis that leishmanolysin serves to protect parasites from the cytolytic effects of various antimicrobial peptides (AMPs) which are important components of the innate immune system. We found that members of the α‐ and θ‐defensins, magainins and cathelicidins had substantially higher leishmanicidal activity against leishmanolysin‐knock out mutants of L. major. Using the magainin analogue, pexiganan, as a model peptide we show that AMP evasion is due to rapid and extensive peptide degradation by wild‐type parasites. Pexiganan‐treatment of knock out mutants induced disruption of surface‐membrane permeability and expression of features of apoptosis including smaller cell size, loss of mitochondrial membrane potential, exposure of surface phosphatidyl serine as well as induction of caspase 3/7 activity. These results demonstrate leishmanolysin as a virulence factor preventing AMP‐mediated apoptotic killing. This study serves as a platform for the dissection of the AMP‐mediated death pathways of Leishmania and demonstrates the potential that AMP evasion plays during host infection by this parasite.
Mechanisms of action of isoniazid
Authors: Timmins Graham S. , Deretic Vojo
Published: October 2006

For decades after its introduction, the mechanisms of action of the front‐line antituberculosis therapeutic agent isoniazid (INH) remained unclear. Recent developments have shown that peroxidative activation of isoniazid by the mycobacterial enzyme KatG generates reactive species that form adducts with NAD+ and NADP+ that are potent inhibitors of lipid and nucleic acid biosynthetic enzymes. A direct role for some isoniazid‐derived reactive species, such as nitric oxide, in inhibiting mycobacterial metabolic enzymes has also been shown. The concerted effects of these activities – inhibition of cell wall lipid synthesis, depletion of nucleic acid pools and metabolic depression – drive the exquisite potency and selectivity of this agent. To understand INH action and resistance fully, a synthesis of knowledge is required from multiple separate lines of research – including molecular genetic approaches, in vitro biochemical studies and free radical chemistry – which is the intent of this review.
Range‐wide genetic analysis provides evidence of natural isolation among populations of the Mongolian endemic Potentilla ikonnikovii Juz. (Rosaceae)
Authors: WESCHE KARSTEN , HENSEN ISABELL , UNDRAKH RAGCHAA
Published: October 2006

Isolated populations are likely to experience a loss of genetic diversity because of reduced gene flow, and the effects of habitat fragmentation are, therefore, central issues in conservation genetics. Here, we present data on genetic diversity and isolation‐by‐distance for the rare central Asian plant Potentilla ikonnikovii (Rosaceae), which occurs in naturally fragmented populations. Sampling covered the entire distributional range of this endemic of southern Mongolia, where the species is restricted to archipelago‐like mountain systems that emerge from the semidesert lowlands of the Gobi region. Random amplified polymorphic DNA analyses revealed modest levels of genetic diversity at both the population and species level. A ΦST of 0.68 indicates that isolation has strong effects on population genetic structure; most variance is kept among populations rather than within, and the two most remote populations were genetically distinct. Mantel statistics showed that genetic distance was highly correlated to spatial distance (RM > 0.6). We conclude that populations of P. ikonnikovii are severely isolated in terms of genetic structure. This may lead to reduced fitness and a crude monitoring scheme is recommended.
Is early flowering in myrmecochorous plants an adaptation for ant dispersal?
Authors: GUITIÁN JAVIER , GARRIDO JOSÉ L.
Published: October 2006

To analyze the extent to which early flowering of specialized myrmecochorous plants (i.e. plants producing elaiosome‐bearing seeds) may be the result of adaptation for ant dispersal, we investigated flowering and fruiting patterns of common herb and shrub‐layer species in a beechwood forest at the western end of the Cantabrian Range (Spain). Over the same period, we estimated ant abundance, the availability of alternative foods for ants, and the rate of removal of seeds by ants. Our results indicate: (i) that the flowering peaks of most strict myrmecochores occurred approximately 4 weeks earlier than in non‐myrmecochores; (ii) that the fruiting peak of both groups of plants occurred around the same time, in early July; (iii) that the peak in ant abundance coincides with the seed availability peak, and precedes the peak in availability of alternative ant foods; and (iv) that the probability of seed removal by Formica rufibarbis (the only ant species present in the study area) varies over the season, peaking in early July. In conclusion, our results show that despite differences in seed size, plants with ant‐dispersed seeds show highly synchronous flowering, suggesting that strict myrmecochores in our study area may have adapted their phenologies to the seasonal availability of dispersers.
Beliefs about using consumer consultants in inpatient psychiatric units
Authors: McCann Terence V. , Baird John , Clark Eileen , Lu Sai
Published: October 2006

ABSTRACT:  A key recommendation of consumer organizations and governments has been the employment of consumer consultants in inpatient psychiatric facilities, but the attitudes of mental health clinicians towards this measure remain inconsistent. The aims of this study were to examine mental health clinicians’ attitudes about the role of mental health consumer consultants in inpatient psychiatric units, and to ascertain if participants’ age, type of inpatient unit, or grade of staff influenced their attitudes towards consultants. The Consumer Participation and Consultant Questionnaire was used, which was adapted from the Mental Health Consumer Participation Questionnaire. A convenience sample of 47 mental health professionals from two adult inpatient psychiatric units located in a large Australian public general hospital participated in the study. The findings, overall, showed that participants supported the inclusion of consumer consultants in psychiatric units in areas that indirectly impinged on their current roles. Age, level of nurses, and place of employment did not affect their beliefs, but type of occupation was influential. Nurses were less supportive of aspects of consumer consultants’ roles that overlapped with the traditional roles of the nurse. The findings have implications for clinical practice, education, and further research, and these are discussed.
Challenging the smoking culture within a mental health service supportively
Authors: Reilly Paul , Murphy Leeann , Alderton Deirdre
Published: October 2006

ABSTRACT:  Smoking is an entrenched part of the culture of mental health care services. This paper discusses the smoking culture in mental health care settings and demonstrates a supportive model to engage staff to actively address their tobacco use and to influence a change in smoking‐related workplace policy, practice, and culture. With management endorsement, two 9‐week staff smoking cessation support groups were implemented and subsidized nicotine replacement therapy was provided to staff within the Alma Street Mental Health Service, Fremantle Hospital, Western Australia. Eighteen staff members from nursing, social work, administration staff, and patient care assistants participated in the group programme. At the conclusion of the programme, 61% (n = 11) of participants had quit as a result of the groups. Furthermore, a 3‐month follow‐up evaluation revealed that 39% (n = 7) of the group had abstained from smoking because of the programme. More importantly, the groups engaged staff to discuss workplace smoking issues and produced five recommendations to review policy and practice to further influence a change in the smoking culture of the mental health care service. The groups also provided the opportunity to develop a model of intervention to address smoking in a mental health setting and to raise the public health role of mental health nurses.
Integrating information and communication technologies in the Turkish primary school system
Authors: Özdemir Selçuk , Kılıç Ebru
Published: October 2006

The paper reports on an investigation into the 1998–2003 Phase 1 of the information and communication technologies (ICTs) component of the Basic Education Program, a major project jointly funded by the Turkish Ministry of National Education (MONE) and the World Bank designed to integrate ICT into the national primary school system. The study involved a search of the literature regarding ICT integration in primary schools, an analysis of MONE and World Bank documentation and face‐to‐face interviews and a questionnaire survey to gauge the experiences and views of the administrators and computer coordinators involved in the project. The findings revealed major shortcomings in the project, and the paper concludes with recommendations for addressing these shortcomings in Phase 2 of the project, which is now under way, again under the aegis of MONE and the World Bank.
Health: Lost: one mental health bill
Authors: FIRTH WILSON
Published: October 2006

The decision to draft a new mental health bill followed the majority conviction in 1998 of Michael Stone for the murder of Lin and Megan Russell two years before. Stone was known to the psychiatric services at the time and had been diagnosed as suffering from a personality disorder. He had been offered help but had not been detained, on the basis that his condition was regarded as not treatable. Then and now the likelihood of benefit from treatment is a requirement to allow the detention of someone with personality disorder.
Language: Diction addiction
Authors: GREEN JONATHON
Published: October 2006

This black diction has become America's addiction. ‐ Kanye West, 'Crack Music', 2005

Kanye West, whose rocketing status in the world of rap has in the last two years made him one of its best‐known stars, should know. If black America's primary contribution to the world is its music ‐ its sportsmen tend to be found in America‐only competitions, for all that some declare themselves 'world series' ‐ then coming up fast to an equal predominence, at least in the world of slang, is black speech.
Self‐protection? Antidumping Duties, Collusion, and FDI*
Authors: Davies Ronald B. , Liebman Benjamin H.
Published: October 2006

It is well established that the threat of antidumping duties can help sustain collusion between a foreign firm and its domestic counterpart. However, when the foreign firm is a multinational with a subsidiary in the domestic country, that subsidiary can undermine efforts for protection, thereby diminishing the threat of duties that would otherwise sustain collusion. Accordingly, we show that the multinational may choose to submit to a tariff even under collusion since evidence indicates that duties are more difficult to remove than initiate. In this way, it is possible to obtain a greater degree of commitment, although it comes at a cost. Nevertheless, we prove that this can be a more profitable strategy than those previously explored. Thus, a parent firm may instruct its subsidiary to support duties against the parent. In fact, we find several cases where subsidiaries of multinationals have indeed filed for protection from their own parents.
Cross‐country Relative Price Volatility: Effects of Market Structure*
Authors: Cheung Yin‐Wong , Fujii Eiji
Published: October 2006

Using annual data on nine manufacturing sectors of 18 OECD countries, the article studies the implications of market structure for cross‐country relative price variability. It is found that, in accordance with predictions from a standard markup pricing model, reductions in market competition, along with increased nominal exchange rate volatility, are associated with greater variability of cross‐country relative prices. The market structure also has similar effects on components of cross‐country relative price variability. The empirical findings are robust to the inclusion of various control variables and alternative sample specifications.
Discontinuities in the male psyche: waiting, deadness and disembodiment. Archetypal and clinical approaches
Authors: Goss Phil
Published: October 2006

Abstract:  The discontinuities of development in the male psyche that are manifested in some analyses in unconscious experiences of inner disintegration are described. Narcissism and a de‐somatized relationship to their own presence are the dominant clinical presentation in these patients. The analyst sometimes experiences these analyses as ‘dead’, as a result of the projection of a ‘dead mother’ object. The question of how psychic deadness and impotence can be worked with is examined.

Clinical experience with these men shows how notions associated with the puer‐senex archetype can illuminate the stark realities of a patient's early experiences, particularly in how mother's presence is felt. A theoretical and clinical bridge is proposed between puer and narcissus to frame how a man may unconsciously strive against psychic fragmentation by clinging to an identification with both—in order to remain intact in the face of being caught in a pre‐pubescent state which reflects the insecure attachment to mother. The author describes how patients may find a more grounded embrace of reality via the use of the analyst's empathy and a greater potency through work in the transference/countertransference. These strengthening achievements help men to begin to leave the ‘dead mother’ behind.
The week the couch arrived
Authors: Tyminski Robert F.
Published: October 2006

Abstract:  Changes in the therapeutic environment can elicit intense and unpredictable responses from patients, who then react to the new elements with their own unique thoughts, fantasies, emotions and behaviours. When the change is very specific, and when it entails implications for the treatment itself, these patient responses can coalesce around more profound experiences of the transference as well as of the countertransference. The author, as a candidate or analyst‐in‐training, purchased an analytic couch for his office and observed the unfolding of what this new couch meant for existing treatments. Using clinical examples, he describes the three most common patient responses that occurred: rejecting, ambivalent, and embracing. The richly variant ideas and fantasies related to the analytic couch are described, and the couch's history within Freudian and Jungian contexts is reviewed. Personal determinants that could lead to the decision of whether to use a couch as part of analysis are considered from the standpoint of the analyst's preferences and own experience with the couch. The couch is discussed as a signifier of the analytic process with cultural meanings alluding not only to familiar stereotypes, but also to psychological healing and self‐development.
Reduced white matter connectivity in the corpus callosum of children with Tourette syndrome
Authors: Plessen Kerstin J. , Grüner Renate , Lundervold Arvid , Hirsch Jochen G. , Xu Dongrong , Bansal Ravi , Hammar Åsa , Lundervold Astri J. , Wentzel‐Larsen Tore , Lie Stein Atle , Gass Achim , Peterson Bradley S. , Hugdahl Kenneth
Published: October 2006

Background:  Brain imaging studies have revealed anatomical anomalies in the brains of individuals with Tourette syndrome (TS). Prefrontal regions have been found to be larger and the corpus callosum (CC) area smaller in children and young adults with TS compared with healthy control subjects, and these anatomical features have been understood to reflect neural plasticity that helps to attenuate the severity of tics.

Method:  CC white matter connectivity, as measured by the Fractional Anisotropy (FA) index from diffusion tensor images, was assessed in 20 clinically well‐defined boys with Tourette syndrome and 20 age‐ and gender‐matched controls.

Results:  The hypothesis that children with TS would show reduced measures of connectivity in CC fibers was confirmed for all subregions of the CC. There was no significant interaction of TS and region. Reductions in FA in CC regions may reflect either fewer interhemispheric fibers or reduced axonal myelination. FA values did not correlate significantly with the severity of tic symptoms. Group differences in measures of connectivity did not seem to be attributable to the presence of comorbid ADHD or OCD, to medication exposure, or group differences in IQ.

Conclusion:  Our findings of a reduced interhemispheral white matter connectivity add to the understanding of neural connectivity and plasticity in the brains of children who have TS.
The neural correlates of attention deficit hyperactivity disorder: an ALE meta‐analysis
Authors: Dickstein Steven G. , Bannon Katie , Xavier Castellanos F. , Milham Michael P.
Published: October 2006

Background:  Attention deficit/hyperactivity disorder (ADHD) is one of the most prevalent and commonly studied forms of psychopathology in children and adolescents. Causal models of ADHD have long implicated dysfunction in fronto‐striatal and frontal‐parietal networks supporting executive function, a hypothesis that can now be examined systematically using functional neuroimaging. The present work provides an objective, unbiased statistically‐based meta‐analysis of published functional neuroimaging studies of ADHD.

Methods:  A recently developed voxel‐wise quantitative meta‐analytic technique known as activation likelihood estimation (ALE) was applied to 16 neuroimaging studies examining and contrasting patterns of neural activity in patients with ADHD and healthy controls. Voxel‐wise results are reported using a statistical threshold of p < .05, corrected. Given the large number of studies examining response inhibition, additional meta‐analyses focusing specifically on group differences in the neural correlates of inhibition were included.

Results:  Across studies, significant patterns of frontal hypoactivity were detected in patients with ADHD, affecting anterior cingulate, dorsolateral prefrontal, and inferior prefrontal cortices, as well as related regions including basal ganglia, thalamus, and portions of parietal cortex. When focusing on studies of response inhibition alone, a more limited set of group differences were observed, including inferior prefrontal cortex, medial wall regions, and the precentral gyrus. In contrast, analyses focusing on studies of constructs other than response inhibition revealed a more extensive pattern of hypofunction in patients with ADHD than those of response inhibition.

Conclusions:  To date, the most consistent findings in the neuroimaging literature of ADHD are deficits in neural activity within fronto‐striatal and fronto‐parietal circuits. The distributed nature of these results fails to support models emphasizing dysfunction in any one frontal sub‐region. While our findings are suggestive of the primacy of deficits in frontal‐based neural circuitry underlying ADHD, we discuss potential biases in the literature that need to be addressed before such a conclusion can be fully embraced.
Structure and function of the superior temporal plane in adult males with cleft lip and palate: pathologic enlargement with no relationship to childhood hearing deficits
Authors: Shriver A.S. , Canady J. , Richman L. , Andreasen N.C. , Nopoulos P.
Published: October 2006

Background:  In a previous study from our lab, adult males with non‐syndromic cleft lip and/or palate (NSCLP) were shown to have significantly lower temporal lobe gray matter volume than matched controls. The current study was designed to begin a regional analysis of specific subregions of the temporal lobe. The superior temporal plane (STP) is a brain region involved in the governance of auditory processing and aspects of language. The cognitive deficit of subjects with NSCLP is characterized by specific deficits in language; therefore this region of the temporal lobe is particularly important to investigate in this population. The STP has been found to be structurally abnormal in subjects with dyslexia, another developmental disorder involving language deficit. The hypothesis for the current study was that the STP in subjects with NSCLP would be structurally abnormal and that the abnormality would be related to cognitive deficit, but not to developmental hearing deficit.

Methods:  Manual tracing of the STP in NSCLP males and matched controls was performed on magnetic resonance imaging (MRI) scans. Ratios of STP to total temporal lobe gray matter volume were calculated and compared across groups. In addition, the morphology of the STP was correlated to cognitive function as well as measures of hearing deficit during infancy and childhood.

Results:  Despite overall deficit in temporal lobe gray matter, the STP is disproportionately large in subjects with NSCLP compared to controls. Further, gray matter volume of the STP was inversely correlated with IQ and language test scores in CLP subjects. Hearing loss throughout childhood and adulthood was not significantly correlated with brain morphology.

Conclusions:  The structure of the superior temporal plane in adult males with NSCLP was disproportionately large. This abnormally increased volume was directly related to IQ, with greater STP volume being associated with lower cognitive functioning, thus characterizing the finding as ‘pathologic enlargement’. Moreover, there was no relationship between the structure of the STP and measures of childhood hearing impairment, supporting the notion that the language deficits of this population are more likely due to abnormal brain development than to the effects of hearing deficit during childhood.
Maternal urinary tract infection and related drug treatments during pregnancy and risk of congenital abnormalities in the offspring
Authors: Bánhidy F , Ács N , Puhó EH , Czeizel AE
Published: October 2006

Objective  The association between urinary tract infection (UTI) of pregnant women and preterm birth/low birthweight is known, but the possible association between UTI and congenital abnormalities (CAs) was evaluated rarely. Only one study showed an association with atrial septal defect, thus we decided to check this possible association.

Design  The population‐based large data set of the Hungarian Case–Control Surveillance of Congenital Abnormalities (HCCSCA); most maternal UTIs were based on medically recorded data.

Setting  The HCCSCA, 1980–1996, contained 22 843 newborns or fetuses with CAs and 38 151 matched controls, i.e. newborn infants without any HCAs.

Population  Hungarian informative offspring: live births, stillbirths and prenatally diagnosed malformed fetuses.

Methods  Case–control pair analysis.

Main outcome measures  Twenty‐five CA groups.

Results  A total of 1542 (6.75%) mothers in the case group had UTI during entire pregnancy compared with 2188 (5.74%) mothers in the control group (adjusted prevalence odds ratios [POR] with 95% CI: 1.15, 1.06–1.24). We did not find a higher prevalence of UTI during the second and/or third months of pregnancy in total case group (adjusted POR with 95% CI: 1.1, 0.9–1.2) and in any group of CAs including atrial septal defect type II.

Conclusions  No evidence for the teratogenic effect of maternal UTI and related drug treatments during early pregnancy.