bluuebunny/crossref_metadata_2025 huggingface dataset:
STATIONARY PATTERNS IN CNN-LIKE ENSEMBLES WITH MODIFIED CELL OUTPUT FUNCTIONS
Authors: KANAKOV OLEG I. , SHALFEEV VLADIMIR D. , FORTI GIAN LUIGI
Published: November 2006

Stationary pattern formation in ensembles of coupled bistable elements is investigated both analytically and by means of numerical simulation. The models considered are similar to cellular nonlinear networks (CNNs) — a well-known class of collective dynamical systems intended mainly for image processing — but differ from them in the type of nonlinear functions contained in their equations of motion — cell output functions. The main subject of interest is the transformation of initial conditions, treated as a representation of a half-tone image, into a steady-state pattern. In the analytical part the location of attractors and their basins of attraction in the phase space are estimated for two types of CNN-like systems. In the simulation part the equations of two lattice systems — a CNN and a CNN-like system with local negative coupling — are integrated numerically with initial conditions taken in the form of a sample halftone image. The dependence of the patterns established in both systems upon parameters is studied and compared. The present paper proves, that CNN-like systems with modified cell output functions may be studied analytically, and results available for conventional CNNs may be adapted to this wider class of lattice systems. From the application point of view, it is shown, that the modification of cell output functions under certain conditions does not lead to a breakdown of the system functionality. Moreover, an example is presented, where such a modification allows to introduce new functionality into a system (namely, controlling contour lines width in an edge-detecting system).
SYNCHRONIZATION CRITERIA FOR LUR'E SYSTEMS BY DYNAMIC OUTPUT FEEDBACK WITH TIME-DELAY
Authors: HUANG XIA , CAO JINDE , HO DANIEL W. C.
Published: November 2006

In this paper a master-slave synchronization scheme is investigated by exploiting a dynamic output feedback control mechanism with time-delay and the influences of time-delay on synchronization are studied. Several new sufficient conditions, which are delay-independent or delay-dependent ones, are presented based on a general class of Lyapunov functions. The obtained results, expressed as matrix inequalities improve and generalize the earlier work in the literature and are readily verified via LMI control toolbox without tuning of parameters and/or matrices. The designs of the controller are implemented by solving a constrained nonlinear optimization problem. Finally, we illustrate our results on Chua's circuits and hyperchaotic attractors.
IMPULSIVE CONTROL FOR T–S FUZZY SYSTEM AND ITS APPLICATION TO CHAOTIC SYSTEMS
Authors: WANG YAN-WU , GUAN ZHI-HONG , WANG HUA O. , XIAO JIANG-WEN
Published: November 2006

An impulsive T–S fuzzy model is presented in this paper. The stability of impulsive controlled T–S fuzzy system has been analyzed theoretically. The proposed impulsive control scheme seems to have a simple control structure and may need less control energy than the normal continuous ones for the stabilization of T–S fuzzy system. Some typical chaotic systems, such as Chua's circuit, Lorenz system and Chen's chaotic system, are considered as illustrations to demonstrate the effectiveness of the proposed control scheme.
BIFURCATION ANALYSIS OF A CIRCUIT-RELATED GENERALIZATION OF THE SHIPMAP
Authors: BIZZARRI FEDERICO , STORACE MARCO , GARDINI LAURA
Published: November 2006

In this paper a bifurcation analysis of a piecewise-affine discrete-time dynamical system is carried out. Such a system derives from a well-known map which has good features from its circuit implementation point of view and good statistical properties in the generation of pseudo-random sequences. The considered map is a generalization of it and the bifurcation parameters take into account some common circuit implementation nonidealities or mismatches. It will be shown that several different dynamic situations may arise, which will be completely characterized as a function of three parameters. In particular, it will be shown that chaotic intervals may coexist, may be cyclical, and may undergo several global bifurcations. All the global bifurcation curves and surfaces will be obtained either analytically or numerically by studying the critical points of the map (i.e. extremum points and discontinuity points) and their iterates. In view of a robust design of the map, this bifurcation analysis should come before a statistical analysis, to find a set of parameters ensuring both robust chaotic dynamics and robust statistical properties.
Pentoxifylline inhibits Ca2+-dependent and ATP proteasome-dependent proteolysis in skeletal muscle from acutely diabetic rats
Authors: Baviera Amanda Martins , Zanon Neusa Maria , Carvalho Navegantes Luiz Carlos , Migliorini Renato Hélios , Kettelhut Isis do Carmo
Published: November 2006

Previous studies from this laboratory have shown that catecholamines exert an inhibitory effect on muscle protein degradation through a pathway involving the cAMP cascade. The present work investigated the systemic effect of pentoxifylline (PTX; cAMP-phosphodiesterase inhibitor) treatment on the rate of overall proteolysis, the activity of proteolytic systems, and the process of protein synthesis in extensor digitorum longus muscles from normal and acutely diabetic rats. The direct in vitro effect of this drug on the rates of muscle protein degradation was also investigated. Muscles from diabetic rats treated with PTX showed an increase (22%) in the cAMP content and reduction in total rates of protein breakdown and in activity of Ca2+-dependent (47%) and ATP proteasome-dependent (23%) proteolytic pathways. The high content of m-calpain observed in muscles from diabetic rats was abolished by PTX treatment. The addition of PTX (10−3M) to the incubation medium increased the cAMP content in muscles from normal (22%) and diabetic (51%) rats and induced a reduction in the rates of overall proteolysis that was accompanied by decreased activity of the Ca2+-dependent and ATP proteasome-dependent proteolytic systems, in both groups. The in vitro addition of H-89, an inhibitor of protein kinase A (PKA), completely blocked the effect of PTX on the reduction of proteolysis in muscles from normal and diabetic rats. The present data suggest that PTX exerts a direct inhibitory effect on protein degradative systems in muscles from acutely diabetic rats, probably involving the participation of cAMP intracellular pathways and activation of PKA, independently of tumor necrosis factor-α inhibition.
Control of tight junctional sealing: role of epidermal growth factor
Authors: Flores-Benítez D. , Ruiz-Cabrera A. , Flores-Maldonado C. , Shoshani L. , Cereijido M. , Contreras R. G.
Published: November 2006

Epithelia can adjust the permeability of their paracellular permeation route to physiological requirements, pathological conditions, and pharmacological challenges. This is reflected by a transepithelial electrical resistance (TER) ranging from a few tenth to several thousands Ω·cm2, depending on the degree of sealing of the tight junction (TJ). The present work is part of an effort to understand the causes and mechanisms underlying these adaptations. We observed that an extract of human urine (hDLU) increases TER in a concentration- and time-dependent manner and is more effective when added from the basolateral side of cultured monolayers of Madin-Darby canine kidney cells than from the apical one. We found that its main TER-increasing component is epidermal growth factor (hEGF), as depletion of this peptide with specific antibodies, or inhibition of its receptor with PD153035, abolishes its effect. Since the permeability of the TJ depends on the expression of several species of membrane proteins, chiefly claudins, we explored whether hDLU can affect five members of the claudin family, the three known members of the ZO family, and occludin. EGF present in hDLU decreases the content of claudins-1 and -2 as well as delocalizes them from the TJ and increases the content of claudin-4. As expected from the fact that the degree of sealing of the TJ must be a physiologically regulated parameter, besides of hEGF, we also found that hDLU appears to contain also other components that decrease TER, claudin-4 and -7, and that seem to act with different kinetics than the TER-increasing ones.
Control of 3D Limb Dynamics in Unconstrained Overarm Throws of Different Speeds Performed by Skilled Baseball Players
Authors: Hirashima Masaya , Kudo Kazutoshi , Watarai Koji , Ohtsuki Tatsuyuki
Published: November 2006

This study investigated how the human CNS organizes complex three-dimensional (3D) ball-throwing movements that require both speed and accuracy. Skilled baseball players threw a baseball to a target at three different speeds. Kinematic analysis revealed that the fingertip speed at ball release was mainly produced by trunk leftward rotation, shoulder internal rotation, elbow extension, and wrist flexion in all speed conditions. The study participants adjusted the angular velocities of these four motions to throw the balls at three different speeds. We also analyzed the dynamics of the 3D multijoint movements using a recently developed method called “nonorthogonal torque decomposition” that can clarify how angular acceleration about a joint coordinate axis (e.g., shoulder internal rotation) is generated by the muscle, gravity, and interaction torques. We found that the study participants utilized the interaction torque to generate larger angular velocities of the shoulder internal rotation, elbow extension, and wrist flexion. To increase the interaction torque acting at these joints, the ball throwers increased muscle torque at the shoulder and trunk but not at the elbow and wrist. These results indicates that skilled ball throwers adopted a hierarchical control in which the proximal muscle torques created a dynamic foundation for the entire limb motion and beneficial interaction torques for distal joint rotations.
Gene expression profiles in anatomically and functionally distinct regions of the normal aged human brain
Authors: Liang Winnie S. , Dunckley Travis , Beach Thomas G. , Grover Andrew , Mastroeni Diego , Walker Douglas G. , Caselli Richard J. , Kukull Walter A. , McKeel Daniel , Morris John C. , Hulette Christine , Schmechel Donald , Alexander Gene E. , Reiman Eric M. , Rogers Joseph , Stephan Dietrich A.
Published: November 2006

In this article, we have characterized and compared gene expression profiles from laser capture microdissected neurons in six functionally and anatomically distinct regions from clinically and histopathologically normal aged human brains. These regions, which are also known to be differentially vulnerable to the histopathological and metabolic features of Alzheimer’s disease (AD), include the entorhinal cortex and hippocampus (limbic and paralimbic areas vulnerable to early neurofibrillary tangle pathology in AD), posterior cingulate cortex (a paralimbic area vulnerable to early metabolic abnormalities in AD), temporal and prefrontal cortex (unimodal and heteromodal sensory association areas vulnerable to early neuritic plaque pathology in AD), and primary visual cortex (a primary sensory area relatively spared in early AD). These neuronal profiles will provide valuable reference information for future studies of the brain, in normal aging, AD and other neurological and psychiatric disorders.
Effects of Uncertainty in Climate Inputs on Simulated Evapotranspiration and Runoff in the Western Arctic
Authors: Rawlins M. A. , Frolking S. , Lammers R. B. , Vörösmarty C. J.
Published: November 2006

Hydrological models require accurate precipitation and air temperature inputs in order to adequately depict water fluxes and storages across Arctic regions. Biases such as gauge undercatch, as well as uncertainties in numerical weather prediction reanalysis data that propagate through water budget models, limit the ability to accurately model the terrestrial arctic water cycle. A hydrological model forced with three climate datasets and three methods of estimating potential evapotranspiration (PET) was used to better understand the impact of these processes on simulated water fluxes across the Western Arctic Linkage Experiment (WALE) domain. Climate data were drawn from the NCEP–NCAR reanalysis (NNR) (NCEP1), a modified version of the NNR (NCEP2), and the Willmott–Matsuura (WM) dataset. PET methods applied in the model were Hamon, Penman–Monteith, and Penman–Monteith using adjusted vapor pressure data.

High vapor pressures in the NNR lead to low simulated evapotranspiration (ET) in model runs using the Penman–Monteith PET method, resulting in increased runoff. Annual ET derived from simulations using Penman–Monteith PET was half the magnitude of ET simulated when the Hamon method was used. Adjustments made to the reanalysis vapor pressure data increased the simulated ET flux, reducing simulated runoff. Using the NCEP2 or WM climate data, along with the Penman–Monteith PET function, results in agreement to within 7% between the simulated and observed runoff across the Yukon River basin. The results reveal the high degree of uncertainty present in climate data and the range of water fluxes generated from common model drivers. This suggests the need for thorough evaluations of model requirements and potential biases in forcing data, as well as corroborations with observed data, in all efforts to simulate arctic water balances.
Internationalizing the struggle against neoliberal social policy
Authors: Tang Kwong-leung , Peters Heather
Published: November 2006

English

The dominant economic philosophy, heavily influenced by neoliberalism, is antagonistic to state intervention. Drawing on the case of Canada, we argue that women's groups could resort to international advocacy to combat neoliberal social policy. Such advocacy has a number of potentials as discussed, including fostering a rights-based discourse.

French

Fortement influencée par le néolibéralisme, la philosophie économique dominante est antagoniste à l'intervention étatique. Nous référant à l'expérience canadienne, nous soutenons que les groupes de femmes pourraient faire appel à des organismes internationaux d'appui et de défense des droits pour combattre les politiques néolibérales sociales. De tels défenseurs peuvent plaider en faveur des femmes des façons suivantes: cette inclus promouvoir un discours fondé sur les droits.

Spanish

La filosofía económica dominante que ha sido influida profundamente por el neo-liberalismo, es contraria a la intervención del estado. Basado en el caso de Canadá, argüimos que los grupos representando a las mujeres recuren a la abogacía internacional para combatir las políticas neo-liberales sociales. Tal forma de abogacía tiene las siguientes características: presiona a los gobiernos a que abandonen políticas contra las mujeres; fomenta un discurso basado en los derechos; y actúa como catalizador para los esfuerzos de implementación a nivel domestico y nacional.
Social workers’ roles in the criminal justice system
Authors: Betancourt Bianca , Dolmage Katie , Johnson Charmonair , Leach Tricia , Menchaca Jonathan , Montero Darrel , Wood Tarina
Published: November 2006

English

This article examines trends in American public opinion on capital punishment between 1953 and 2002. It seems that Americans believe that the government spends too little on crime deterrence, that courts are not harsh enough with criminals, and that the death penalty is appropriate for murderers. Implications for social workers are suggested.

French

Cet article examine les tendances de l'opinion publique américaine concernant la peine capitale entre 1953 et 2002. Il semble que les américains croient que le gouvernement dépense trop peu sur des stratégies de prévention ou de dissuasion du crime, que les tribunaux manquent de sévérité face aux criminels et que la peine de mort est appropriée pour les meurtriers. Des implications pour les travailleurs sociaux sont énoncées.

Spanish

Este artículo examina la tendencia in la opinión pública americana con respecto a la pena capital durante 1953-2002. Parece que los americanos creen: el gobierno gasta muy poco en combatir el crimen, las cortes no son lo suficientemente duras con los criminales, y la pena de muerte es apropiada para los asesinos. Las implicaciones para los trabajadores sociales son sugeridas.
Opportunities and challenges for social workers crossing borders
Authors: White Ruth
Published: November 2006

English

Using the author's experience as a social worker who has studied and worked in Canada, Belize, Brussels, Jamaica, London and the USA, this article explores some of the issues facing social work students, scholars and practitioners who migrate across international borders. Topics include equivalency of qualifications, visas and socio-cultural issues.

French

L'auteur de cette recherche s'appuie sur son expérience d'étudiant et de professionnel dans le domaine du travail social au Canada, au Belize, à Bruxelles, en Jamaïque et aux États-Unis pour explorer certains enjeux auxquels sont confrontés les étudiants, les boursiers ou les praticiens oeuvrant à l'international. Les équivalences en matière de qualification, les visas et les questions d'ordre socioculturelles sont au nombre des thèmes abordés.

Spanish

Basándose en la experiencia del autor, que como trabajador social estudió y trabajó en el Canadá, Belice, Bruselas, Jamaica, Londres, y los Estados Unidos, se exploran algunas cuestiones con las que se encuentran estudiantes, investigadores y profesionales de trabajo social cuando emigran fuera de sus países. Se exploran los temas de equivalencia de títulos, visas y asuntos culturales.
War President
Authors: Eichenberg Richard C. , Stoll Richard J. , Lebo Matthew
Published: November 2006

The authors estimate a model of the job approval ratings of President George W. Bush that includes five sets of variables: a “honeymoon” effect, an autoregressive function that tracks a decline in approval, measures of economic performance, measures of important “rally events,” and a measure of the costs of war—in this case, the U.S. death toll in the Iraq War. Several significant effects are found, including the rally that followed the attacks of September 11, 2001; the commencement of the war in Iraq; and the capture of Baghdad in April 2003. Since the beginning of the war in Iraq, however, the casualties of war have had a significant negative impact on Bush’s approval ratings. Although the effects of additional battle deaths in Iraq will decrease approval only marginally, results suggest that there is also little prospect for sustained improvement so long as casualties continue to accumulate.
Building Social Capital in Vulnerable Families
Authors: Terrion Jenepher Lennox
Published: November 2006

Researchers suggest that key to addressing the needs of vulnerable families is to involve parents in their child's academic life. However, this article argues, it is not simply involvement that matters for the improved functioning of these families but the production of the three dimensions of social capital (bonding, bridging, and linking) through human interaction in the school that reduces risk factors in vulnerable families. Thematic analysis of semistructured interviews with participants and community stakeholders in a school-based family support program, Families and Schools Together (F&ST), revealed six success markers implicit in the narratives. The success markers demonstrate that the major outcome of F&ST is the production of social capital in all three of its dimensions. The article highlights the importance of social capital in building stronger, more resilient families.
Law and Terror in the Age of Colonial Constitution Making
Authors: Samaddar Ranabir
Published: November 2006

In this exploration of the close relationship between terror and law, I have several aims. First, I want to demonstrate that the relationship between terror and law is not a question of relating violence just to law, but to the very process of constitution making.
Constitutional Equality and the Politics of Representation in India
Authors: Hasan Zoya
Published: November 2006

It is widely believed that an historic shift has taken place in the forms and modes of political representation available to people seeking representation of their interests and social claims. Two changes are noteworthy. From the classic patterns of the earlier 20th century, based on social relations forged in workplaces, organized in trade unions and mass organizations linked to programmatic political parties, it has moved to a ‘new politics’ of social movements, voluntary associations, NGOs, etc., rather than political parties, and local rather than national concerns. The second change is in the process of representation marked by a greater emphasis on descriptive representation and participation in decision-making. Today, equitable and fair-minded policies can be objected to on the grounds that the processes by which they were arrived at were undemocratic and excluded women and minorities, for instance. Even when there are no laws that require it, many political parties have decided their lists are not properly representative without certain numbers of people from different groups.
Wars without End: The Case of the Naga Hills
Authors: Franke Marcus
Published: November 2006

By employing a longer historical perspective it can be shown that the war that afflicts the Naga Hills today, and which has spread to the whole of what is called India's North-East, may be understood as the continuation of the imperial conquest begun by the British. This longer historical perspective might be summarized as follows: the pre-modern multi-centred world knew regional empires, states, etc., but due to a lack of means of communication and control, in addition to a shortage of manpower and a surplus of land, the centres did not seriously try to subjugate inaccessible frontier areas that constituted a refuge for populations outside the larger polities. When European states began to erect world-wide empires, many of these former regional empires and states turned into peripheral colonies from the perspective of the European metropolises. The frontier areas of these peripheries were in many cases pacified, but not really integrated into the administration of the colonies, and when these colonies themselves returned from periphery to centre by regaining their independence, they in turn endeavoured to incorporate the former frontiers that represent the peripheries of today. In this way, what was once the colonized periphery has transformed into a metropolis and now exerts imperial policy on the former frontier, its contemporary periphery.
The Biblical Roots of Democracy
Authors: Roshwald Mordecai
Published: November 2006

It is customary to look for the roots of modern democracy in ancient Greece - specifically in ancient Athens. Allowance is made, of course, for the difference between the direct democracy of Athens and the representative democracy of the modern era. Similarly, the limitation of the democratic participation in state affairs to the free male citizens of Athens, to the exclusion of slaves, aliens and women, is noted. Yet, barring these differences, the Athenian democracy, at least from the reform of Ephialtes in 462 BC on through most of the following period till the ascendancy of Macedonia, clearly displays the popular participation of the citizens in the ruling of the polis. Thus, a fundamental link is established between Greek antiquity and modernity.
Preparation and Properties of Three-dimensional Braided UHMWPE Fiber Reinforced PMMA Composites
Authors: Zhang Y. D. , Wang Y. L. , Huang Y. , Wan Y. Z.
Published: November 2006

In this study, three-dimensional (3-D) braided UHMWPE fiber reinforced PMMA resin (UHMWPE3DPMMA) composites are prepared by the vacuum impregnation technique. Research has been carried out to determine the mechanical properties and investigate the effects of fiber surface treatment and fiber volume fraction on the mechanical properties of the compsites. The results show that the UHMWPE3DPMMA composites possess excellent impact strength. XPS analysis reveals that oxygen-containing functional groups on the fiber surface increase after fiber surface treatment. It is found that enhanced interface adhesion results in substantial improvement of the flexural and shear properties, but a reduction in the impact strength. The flexural strength and modulus and the longitudinal shear strength increase markedly with increasing fiber volume fraction, attain maximum values at a Vf of 38%, but then decrease. The transverse shear strength exhibits continuous increase with Vf.
The pragmatics of political apologies
Authors: Harris Sandra , Grainger Karen , Mullany Louise
Published: November 2006

Despite the wealth of literature generated over the past two decades on the apology as a speech act, the political apology has been relatively neglected as a research topic. This article aims to examine the pragmatics of such apologies as a generic type of discourse by identifying their salient characteristics: they are in the public domain and highly mediated; they are generated by (and generate) conflict and controversy; on the basis of media and viewer evaluations/judgements, they need to contain both an illocutionary force indicating device ( Ifid) and an explicit expression of the acceptance of responsibility/blame for the ‘offence’ in order to be clearly perceived as valid apologies; and they rarely, if ever, involve an expression of absolution. Drawing primarily on data concerning recent political events in the UK (especially the Iraq War), the article attempts to set out and illustrate the different types of political apology. The resulting analysis is related both to previous and current apology research and to recent developments in politeness theory.
Magnetoencephalography as a Research Tool in Neuroscience: State of the Art
Authors: Ioannides Andreas A.
Published: November 2006

Magnetoencephalography (MEG) is a noninvasive neuroimaging method for detecting, analyzing, and interpreting the magnetic field generated by the electrical activity in the brain. Modern hardware can capture the MEG signal at hundreds of points around the head in a snapshot lasting only a fraction of a millisecond. The sensitivity of modern hardware is high enough to permit the extraction of a clean signal generated by the brain well above the noise level of the MEG hardware. It is possible to identify signatures of superficial and often deep generators in the raw MEG signal, even in snapshots of data. In a more quantitative way, tomographic images of the electrical current density in the brain can be extracted from each snapshot of MEG signal, providing a direct correlate of coherent collective neuronal activity. A number of recent studies have scrutinized brain function in the new spatiotemporal window that real-time tomographic analysis of MEG signals has opened. The results have allowed the variability in a single area to be seen in the context of activity in other areas and background rhythmic activity. In this view, normal brain function is seen as a cascade of extremely fast events and the unfolding of specialized processes, segregated in space and time and organized into well-defined stages of processing.
Microtubule: A Common Target for Parkin and Parkinson’s Disease Toxins
Authors: Feng Jian
Published: November 2006

Parkinson’s disease (PD) is characterized by the selective loss of nigral dopaminergic (DA) neurons, which have long axons enriched with microtubules. Depolymerization of microtubules by PD toxins such as rotenone disrupts vesicular transport. The ensuing accumulation of vesicles in the cell body leads to increased cytosolic concentration of dopamine due to leakage of the vesicles. Elevated oxidative stress induced by dopamine oxidation may thus trigger the selective demise of DA neurons. Many strategies have been developed to protect DA neurons by stabilizing microtubules either directly or through intracellular signaling cascades. On the other hand, parkin, one of the most frequently mutated genes in PD, encodes for a protein-ubiquitin E3 ligase that strongly binds to microtubules. Parkin stabilizes microtubules through three domains that provide strong and independent interactions with tubulin and microtubules. These interactions anchor parkin on microtubules and may facilitate its E3 ligase activity on misfolded proteins transported along microtubules. Thus, parkin and rotenone, two prominent genetic and environmental factors linked to PD, act in an opposing manner on the same molecular target in the cell, microtubules, whose destruction underlies the selective vulnerability of dopaminergic neurons.
Immunogenicity of a polyvalent HIV-1 candidate vaccine based on fourteen wild type gp120 proteins in golden hamsters
Authors: Azizi Ali , Anderson David E , Ghorbani Masoud , Gee Katrina , Diaz-Mitoma Francisco
Published: November 2006

Background

One of the major obstacles in the design of an effective vaccine against HIV-1 is the hypervariability of the HIV-1 envelope glycoprotein. Most HIV-1 vaccine candidates have utilized envelope glycoprotein from a single virus isolate, but to date, none of them elicited broadly reactive humoral immunity. Herein, we hypothesised that a cocktail of HIV-1 gp120 proteins containing multiple epitopes may increase the breadth of immune responses against HIV-1. We compared and evaluated the immunogenicity of HIV-1 vaccines containing either gp120 protein alone or in combinations of four or fourteen gp120s from different primary HIV-1 isolates in immunized hamsters.

Results

We amplified and characterized 14 different gp120s from primary subtype B isolates with both syncytium and non-syncytium inducing properties, and expressed the proteins in Chinese Hamster Ovary (CHO) cell lines. Purified proteins were used either alone or in combinations of four or fourteen different gp120s to vaccinate golden hamsters. The polyvalent vaccine showed higher antibody titers to HIV-1 subtype B isolates MN and SF162 compared to the groups that received one or four gp120 proteins. However, the polyvalent vaccine was not able to show higher neutralizing antibody responses against HIV-1 primary isolates. Interestingly, the polyvalent vaccine group had the highest proliferative immune responses and showed a substantial proportion of cross-subtype CD4 reactivity to HIV-1 subtypes B, C, and A/E

Conclusion

Although the polyvalent approach achieved only a modest increase in the breadth of humoral and cellular immunity, the qualitative change in the vaccine (14 vs. 1 gp120) resulted in a quantitative improvement in vaccine-induced immunity.
Ocular immune privilege is circumvented by CD4+ T cells, leading to the rejection of intraocular tumors in an IFN-γ-dependent manner
Authors: Dace Dru S , Chen Peter W , Alizadeh Hassan , Niederkorn Jerry Y
Published: November 2006

Although intraocular tumors reside in an immune-privileged site, they can circumvent immune privilege and undergo rejection, which typically follows one of two pathways. One pathway involves CD4+ T cells, delayed-type hypersensitivity (DTH), and the culmination in ischemic necrosis of the tumor and phthisis (atrophy) of the eye. The second pathway is DTH-independent and does not inflict collateral injury to ocular tissues, and the eye is preserved. In this study, we used a well-characterized tumor, Ad5E1, to analyze the role of IFN-γ in the nonphthisical form of intraocular tumor rejection. The results showed that IFN-γ induced tumor cell apoptosis, inhibited tumor cell proliferation, and promoted rejection by inhibiting angiogenesis. Microarray analysis revealed that IFN-γ induced up-regulation of five antiangiogenic genes and down-regulation of four proangiogenic genes in Ad5E1 tumor cells. Although IFN-γ knockout (KO) mice have progressively growing intraocular tumors, IFN-γ was not needed for the elimination of extraocular tumors, as all IFN-γ KO mice rejected s.c. tumor inocula. This represents a heretofore unrecognized role for IFN-γ in circumventing ocular immune privilege and eliminating intraocular tumors. The findings also reveal that some IFN-γ-independent tumor rejection processes are excluded from the eye and may represent a new facet of ocular immune privilege.
Klinefelter's syndrome (karyotype 47, XXY) and
schizophrenia-spectrum pathology
Authors: van Rijn Sophie , Aleman André , Swaab Hanna , Kahn René S.
Published: November 2006

Klinefelter's syndrome, characterised by a 47, XXY chromosomal pattern, has
largely been associated with physical abnormalities. Here, we report high
levels of schizophrenia-spectrum pathology in 32 men with this syndrome in
comparison with 26 healthy controls. This may have implications for
treatment of Klinefelter's syndrome and suggests that the X chromosome may
be involved in the aetiology of schizophrenia.
Progression of mild cognitive impairment to dementia: a challenge to current thinking
Authors: Busse Anja , Angermeyer Matthias C. , Riedel-Heller Steffi G.
Published: November 2006

Background

Studies of conversion from mild cognitive impairment to dementia suggest a linear progression over time. Conversion rates during lifetime may extend to 80–90%.

Aims

This study examines the time-dependent evolution from mild cognitive impairment to dementia. Current assumptions regarding yearly and lifetime conversion rates are challenged.

Method

A community sample of 1045 dementia-free individuals aged 75 years and over was examined by neuropsychological testing based on 6 years of observation.

Results

Approximately 60–65% of people with mild cognitive impairment develop clinical dementia during their life. Progression from mild cognitive impairment to dementia appears to be time dependent, occurring primarily within the initial 18 months.

Conclusions

Further long-term studies are needed to examine the time-dependent evolution from mild cognitive impairment to dementia and to establish age-specific conversion rates during lifetime.
Individual- and area-level predictors of self-harm
repetition
Authors: Johnston Amy , Cooper Jayne , Webb Roger , Kapur Navneet
Published: November 2006

Background

No ecological studies have examined the relationship between area
characteristics, individual characteristics and self-harm repetition.

Aims

To investigate the association between area-level factors and incidence
and repetition of self-harm, and to identify which area-level factors are
independently associated with repetition after adjustment for individual
factors.

Method

Prospective cohort study using the Manchester Self-Harm database. Adults
who were resident in Manchester and presented to an emergency department
following self-harm between 1997 and 2002 were included
(n=4743). The main outcome measure was repeat
self-harm within 6 months of the index episode.

Results

Four individual factors (previous self-harm, previous psychiatric
treatment, employment status, marital status) and one area-based factor
(proportion of individuals who were of White ethnicity) were
independently associated with repetition.

Conclusions

Repetition of self-harm may be more strongly related to individual
factors than to area characteristics. We need to better understand the
processes underlying ecological associations with suicidal behaviour
before embarking on area-based interventions.
Changes in genetic and environmental influences on depressive
symptoms across adolescence and young adulthood
Authors: Lau Jennifer Y. F. , Eley Thalia C.
Published: November 2006

Background

Depression rises markedly in adolescence, a time when increased and new
genetic influences have been reported.

Aims

To examine ‘new’ and ‘stable’ genetic and environmental factors on
depressive symptoms in adolescence and young adulthood.

Method

A questionnaire survey investigated a sample of twin and sibling pairs at
three time points over an approximately 3-year period. Over 1800 twin and
sibling pairs reported depressive symptoms at the three time points. Data
were analysed using multivariate genetic models.

Results

Depressive symptoms at all time points were moderately heritable with
substantial non-shared environmental contributions. Wave I genetic
factors accounted for continuity of symptoms at waves 2 and 3. ‘New’
genetic effects at wave 2 also influenced wave 3 symptoms. New non-shared
environmental influences emerged at each time point.

Conclusions

New genetic and environmental influences may explain age-related
increases in depression across development.
Crisis resolution/home treatment teams and psychiatric admission
rates in England
Authors: Glover Gyles , Arts Gerda , Babu Kannan Suresh
Published: November 2006

Background

Introduction of crisis resolution/home treatment teams has been
associated with a reduction in hospital admissions in trials. Between
2001 and 2004 there was a rapid expansion in the numbers of these teams
in England.

Aims

To examine whether national implementation of these teams was associated
with comparable reductions in admissions.

Method

Observational study using routine data covering working age adult
patients in 229 of the 303 local health areas in England from 1998/9 to
2003/4.

Results

Admissions fell generally throughout the period, particularly for younger
working age adults. Introduction of crisis resolution teams was
associated with greater reductions for older working age women (35–64
years); teams always on call were associated with additional reductions
for older men and younger women. By the end of the study admissions had
fallen by 10% more in the 34 areas with crisis resolution teams in place
since 2001, and by 23% more in the 12 of these on call around the clock
than in the 130 areas without such teams by 2003/4. Reductions in bed use
were smaller. Introduction of assertive outreach teams was not associated
with overall reductions in admissions.

Conclusions

Introduction of crisis resolution teams has been associated with
reductions in admissions.
Clinical and social determinants of duration of untreated
psychosis in the ÆSOP first-episode psychosis study
Authors: Morgan Craig , Abdul-Al Rudwan , Lappin Julia M. , Jones Peter , Fearon Paul , Leese Morven , Croudace Tim , Morgan Kevin , Dazzan Paola , Craig Tom , Leff Julian , Murray Robin ,   ÆSOP Study Group
Published: November 2006

Background

Despite considerable research investigating the relationship between a
long duration of untreated psychosis (DUP) and outcomes, there has been
much less considering predictors of a long DUP.

Aims

To investigate the clinical and social determinants of DUP in a large
sample of patients with a first episode of psychosis.

Method

All patients with a first episode of psychosis who made contact with
psychiatric services over a 2-year period and were living in defined
catchment areas in London and Nottingham, UK were included in the ÆSOP
study Data relating to clinical and social variables and to DUP were
collected from patients, relatives and case notes.

Results

An insidious mode of onset was associated with a substantially longer DUP
compared with an acute onset, independent of other factors. Unemployment
had a similar, if less strong, effect. Conversely family involvement in
help-seeking was independently associated with a shorter duration. There
was weak evidence that durations were longer in London than in
Nottingham.

Conclusions

These findings suggest that DUP is influenced both by aspects of the
early clinical course and by the social context.
A Brief Exposure to Moderate Passive Smoke Increases Metabolism and Thyroid Hormone Secretion
Authors: Metsios Giorgos S. , Flouris Andreas D. , Jamurtas Athanasios Z. , Carrillo Andres E. , Kouretas Demetrios , Germenis Anastasios E. , Gourgoulianis Konstantinos , Kiropoulos Theodoros , Tzatzarakis Manolis N. , Tsatsakis Aristeidis M. , Koutedakis Yiannis
Published: November 2006

Context: Active smoking influences normal metabolic status and thyroid function.

Objective: The objective was to assess experimentally the effects of 1 h of moderate passive smoking in a controlled simulated bar/restaurant environment on the metabolism and thyroid hormone levels in healthy nonsmokers.

Participants: Eighteen (nine females, nine males) healthy individuals (mean ± sd: age, 25.3 ± 3.1 yr; height, 174.0 ± 10.1 cm; weight, 65.2 ± 13.7 kg) participated in the study.

Design: In repeated-measures randomized blocks, participants visited the laboratory on 2 consecutive days. In the experimental condition, they were exposed to 1 h of moderate passive smoking at a carbon monoxide concentration of 23 ± 1 ppm in an environmental chamber, whereas in the control condition participants remained in the same chamber for 1 h breathing normal atmospheric air.

Main Outcome Measures: In both conditions, cotinine serum and urine levels, resting energy expenditure (REE), as well as concentration of T3, free T4, and TSH were assessed before participants entered the chamber and immediately after their exit. Heart rate and blood pressure were tested in 10-min intervals during all REE assessments.

Results: The mean ± sd difference of serum and urine cotinine levels (−0.27 ± 3.94 vs. 14.01 ± 6.54 and 0.05 ± 2.07 vs. 7.23 ± 3.75, respectively), REE (6.73 ± 98.06 vs. 80.58 ± 120.91) as well as T3 and free T4 (0.05 ± 0.11 vs. 0.13 ± 0.12 and 0.02 ± 0.15 vs. 0.22 ± 0.20) were increased in the experimental compared with the control condition at baseline and follow-up (P < 0.05). No statistically significant variation was observed in the mean difference of the remaining parameters (P > 0.05). Serum and urine cotinine values were linearly associated with REE (P < 0.05).

Conclusion: One hour of passive smoking at bar/restaurant levels is accompanied by significant increases in metabolism and thyroid hormone levels.
Kinesin 6 family member Subito participates in mitotic spindle assembly and interacts with mitotic regulators
Authors: Cesario Jeff M. , Jang Janet K. , Redding Bethany , Shah Nishit , Rahman Taslima , McKim Kim S.
Published: November 2006

Drosophila Subito is a kinesin 6 family member and ortholog of mitotic kinesin-like protein (MKLP2) in mammalian cells. Based on the previously established requirement for Subito in meiotic spindle formation and for MKLP2 in cytokinesis, we investigated the function of Subito in mitosis. During metaphase, Subito localized to microtubules at the center of the mitotic spindle, probably interpolar microtubules that originate at the poles and overlap in antiparallel orientation. Consistent with this localization pattern, subito mutants improperly assembled microtubules at metaphase, causing activation of the spindle assembly checkpoint and lagging chromosomes at anaphase. These results are the first demonstration of a kinesin 6 family member with a function in mitotic spindle assembly, possibly involving the interpolar microtubules. However, the role of Subito during mitotic anaphase resembles other kinesin 6 family members. Subito localizes to the spindle midzone at anaphase and is required for the localization of Polo, Incenp and Aurora B. Genetic evidence suggested that the effects of subito mutants are attenuated as a result of redundant mechanisms for spindle assembly and cytokinesis. For example, subito double mutants with ncd, polo, Aurora B or Incenp mutations were synthetic lethal with severe defects in microtubule organization.
ARAP2 effects on the actin cytoskeleton are dependent on Arf6-specific GTPase-activating-protein activity and binding to RhoA-GTP
Authors: Yoon Hye-Young , Miura Koichi , Cuthbert E. Jebb , Davis Kathryn Kay , Ahvazi Bijan , Casanova James E. , Randazzo Paul A.
Published: November 2006

ARAP2 is a protein that contains both ArfGAP and RhoGAP domains. We found that it is a phosphatidylinositol (3,4,5)-trisphosphate-dependent Arf6 GAP that binds RhoA-GTP but lacks RhoGAP activity. In agreement with the hypothesis that ARAP2 mediates effects of RhoA, endogenous ARAP2 associated with focal adhesions (FAs) and reduction of ARAP2 expression, by RNAi, resulted in fewer FAs and actin stress fibers (SFs). In cells with reduced levels of endogenous ARAP2, FAs and SFs could be restored with wild-type recombinant ARAP2 but not mutants lacking ArfGAP or Rho-binding activity. Constitutively active Arf6 also caused a loss of SFs. The Rho effector ROKα was ineffective in restoring FAs. Conversely, overexpression of ARAP2 did not restore SFs in cells treated with a ROK inhibitor but induced punctate accumulations of paxillin. We conclude that ARAP2 is an Arf6GAP that functions downstream of RhoA to regulate focal adhesion dynamics.
Multiple domains in Siz SUMO ligases contribute to substrate selectivity
Authors: Reindle Alison , Belichenko Irina , Bylebyl Gwendolyn R. , Chen Xiaole L. , Gandhi Nishant , Johnson Erica S.
Published: November 2006

Saccharomyces cerevisiae contains two Siz/PIAS SUMO E3 ligases, Siz1 and Siz2/Nfi1, and one other known ligase, Mms21. Although ubiquitin ligases are highly substrate-specific, the degree to which SUMO ligases target distinct sets of substrates is unknown. Here we show that although Siz1 and Siz2 each have unique substrates in vivo, sumoylation of many substrates can be stimulated by either protein. Furthermore, in the absence of both Siz proteins, many of the same substrates are still sumoylated at low levels. Some of this residual sumoylation depends on MMS21. Siz1 targets its unique substrates through at least two distinct domains. Sumoylation of PCNA (proliferating cell nuclear antigen) and the splicing factor Prp45 requires part of the N-terminal region of Siz1, the `PINIT' domain, whereas sumoylation of the bud neck-associated septin proteins Cdc3, Cdc11 and Shs1/Sep7 requires the C-terminal domain of Siz1, which is also sufficient for cell cycle-dependent localization of Siz1 to the bud neck. Remarkably, the non-sumoylated septins Cdc10 and Cdc12 also undergo Siz1-dependent sumoylation if they are fused to the short ΨKXE SUMO attachment-site sequence. Collectively, these results suggest that local concentration of the E3, rather than a single direct interaction with the substrate polypeptide, is the major factor in substrate selectivity by Siz proteins.
Influx of extracellular Ca2+ is necessary for electrotaxis inDictyostelium
Authors: Shanley Lynne J. , Walczysko Petr , Bain Mary , MacEwan David J. , Zhao Min
Published: November 2006

Intracellular free Ca2+ ([Ca2+]i) is a pivotal signalling element in cell migration and is thought to be required for chemotaxis of Dictyostelium. Ca2+ signalling may also be important for electrotaxis. However this suggestion has been controversial. We show that electric fields direct Dictyostelium cells to migrate cathodally and increase [Ca2+]i in Dictyostelium cells, as determined by Fluo-3 AM imaging and 45Ca2+ uptake. Omission of extracellular Ca2+([Ca2+]e) and incubation with EGTA abolished the electric-field-stimulated [Ca2+]i rise and directional cell migration. This suggests a requirement for [Ca2+]e in the electrotactic response. Deletion of iplA, a gene responsible for chemoattractant-induced [Ca2+]i increase, had only a minor effect on the electric-field-induced [Ca2+]i rise. Moreover, iplA-null Dictyostelium cells showed the same electrotactic response as wild-type cells. Therefore, iplA-independent Ca2+ influx is necessary for electrotactic cell migration. These results suggest that the [Ca2+]i regulatory mechanisms induced by electric fields are different from those induced by cAMP and folic acid in Dictyostelium cells. Different roles of the iplA gene in chemoattractant-induced and electrically induced Ca2+ signalling, and different effects of [Ca2+]i elevation on chemotaxis and electrotaxis indicate that the chemoattractant and electric cues activate distinctive initial signalling elements.