bluuebunny/crossref_metadata_2025 huggingface dataset:
Description of a return‐to‐work occupational therapy programme for stroke rehabilitation in Singapore
Authors: Chan Mei Leng
Published: March 2008

Stroke is the fourth leading cause of death and the major cause of disability in Singapore. The number of stroke survivors is expected to rise with the increase in the ageing population. This paper describes how occupational therapists are involved in stroke and work rehabilitation in Singapore. A retrospective study of stroke clients referred to a vocational assessment unit in 2004 showed that 55% of the clients were able to return to work. The majority of the clients changed their job positions from blue‐collar workers to clerical workers. On the other hand, the main reasons for poor outcome were: unfit to work in general, needed further rehabilitation, further medical care was indicated, failed to meet appointments and withdrawal from the job trial. Three case vignettes are discussed to illustrate the multifactorial aspects influencing positive work outcomes. Further research is needed in exploring the factors that affect stroke rehabilitation and return‐to‐work outcomes. Copyright © 2008 John Wiley & Sons, Ltd.
Stabilization and destabilization in non‐conservative gyroscopic systems
Authors: Kirillov Oleg N.
Published: March 2008

Stability of a linear autonomous non‐conservative system in presence of potential, gyroscopic, dissipative, and nonconservative positional forces is studied. The cases when the non‐conservative system is close to a gyroscopic system or to a circulatory one, are examined. It is known that the marginal stability of gyroscopic and circulatory systems can be destroyed or improved up to asymptotic stability due to action of small non‐conservative positional and velocity‐dependent forces. The present contribution shows that in both cases the boundary of the asymptotic stability domain of the perturbed system possesses singularities such as “Dihedral angle” and “Whitney umbrella” that govern stabilization and destabilization. Approximations of the stability boundary near the singularities and estimates of the critical gyroscopic and circulatory parameters are found in an analytic form. In case of two degrees of freedom these estimates are obtained in terms of the invariants of matrices of the system. As an example, the asymptotic stability domain of the modified Maxwell‐Bloch equations is investigated with an application to the stability problems of gyroscopic systems with stationary and rotating damping, such as the Crandall gyropendulum, tippe top and Jellet's egg. An instability mechanism in a system with two degrees of freedom, originating after discretization of models of a rotating disc in frictional contact and possessing the spectral mesh in the plane ‘frequency’ versus ‘angular velocity’, is described in detail and its role in the disc brake squeal problem is discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On soft‐fuzzy computing and modelling
Authors: Kosiński Witold
Published: March 2008

In real‐life problems both parameters and data used in mathematical modelling are vague. Pattern recognition, system modelling, diagnosis, image analysis, fault detection and others are fields where soft calculation with unprecise, fuzzy, objects plays an important role. In the presentation recent results in the theory of ordered fuzzy numbers and their normed algebra are shortly reviewed. Then possible applications in modelling dynamical systems and mechanics are presented. From the classical framework known algebraic and evolution equations describing such systems are transformed to their fuzzy versions. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Controllability of neutral functional evolution integrodifferential systems with infinite delay
Authors: Balachandran K.
Published: March 2008

In this paper we establish sufficient conditions for the controllability of neutral functional evolution integrodifferential systems. The results are obtained by using analytic semigroup theory and the Nussbaum fixed point theorem. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Control analysis for water quality problem
Authors: Louaked Mohammed , Saïdi Abdelkader
Published: March 2008

The optimal control of water quality model is considered. We analyze a regularized version of the pointwise control. A numerical algorithm is presented. The solution approach is a combination of a TVD scheme for the shallow water equations and a purley deterministic particle method for the pollutant problem. We present some computational results. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dual‐based error analysis for uncertainty quantification in a chemical system
Authors: Mathelin Lionel , Le Maître Olivier P.
Published: March 2008

An a posteriori error estimation for the numerical solution of a stochastic variational problem arising in the context of parametric uncertainty is presented. The discretization of the stochastic variational problem uses piecewise continuous orthogonal polynomials in the stochastic domain. The a posteriori methodology is derived by measuring the error as the functional difference between the continuous and discrete solutions. An example is shown on a chemical system which reaction rates are uncertain. The present approach efficiency in providing a good accuracy in the uncertainty quantification at a reasonable computational cost is demonstrated. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stability and robustness properties of a class of discrete–time residual generators
Authors: Stoica Adrian–Mihail
Published: March 2008

The aim of this paper is to present a design methodology for an observer–based fault detection filter. This approach allows to compute a filter gain such that both fault detection and disturbance attenuation requirements are accomplished. The developments are based on H∞ optimization in the discrete–time framework. The existence conditions for the observer–based detection filter are expressed in terms of feasibility of a system of matrix inequalities. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerical methods for 2D weakly singular Volterra integral equations of the second kind
Authors: Tynda Alexander N.
Published: March 2008

The paper is dedicated to the numerical solution of 2D weakly singular Volterra integral equations with two different kernels. In order to weaken a singularity influence on the numerical computations we transform these equations in both cases into equivalent equations. The piecewise polynomial approximation of the exact solution is then applied. For numerical computing of weakly singular integrals we construct the special Gauss‐type cubature formula based on a nonuniform grid. Also we suggest the practical mesh which is less nonuniform than standard graded mesh tk = (k/N)r /(1–α) T, and at the same time it gives an equivalent approximation error for the functions from Cr,α (0, T ]. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nonlinear dynamics of an inclined cable subjected to boundary motion conditions
Authors: Woszczyna Anna , Bryja Danuta , Prokopowicz Dawid
Published: March 2008

The paper is devoted to the dynamic modelling of pretensed cable with geometry distinguished by a small or large sag‐tospan ratio and horizontal or inclined cable chord. Spatial cable vibrations are considered from the viewpoint of kinematic excitation caused by a motion of connecting points between the cable and suspended structure or pylon. The nonlinear equations describing in‐plane and out‐of‐plane cable vibrations are derived and solved by standard Galerkin's procedure. Linear and nonlinear solutions for simple model of cable‐stayed bridge loaded by moving unit force are presented. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Problem of magnetoelasticity for a solid with the spherical cavity
Authors: Dashko Olga
Published: March 2008

The solution of a static problem of magnetoelastisity for a soft ferromagnetic elastic solid with the spherical cavity is obtained on the base of the linear theory of Brown, Pao and Yeh. It is assumed that the solid has a multi‐domain structure, so the hysteresis loss and remanent magnetization are neglected. The solid is affected by a magnetic field which is uniform at infinity and determined by the magnetic induction vector. The cavity causes some distortion of the field distribution near the interface. So the field induces magnetic moments and produces stresses and deformations in the body. The problem is solved for an unperturbed strain state. An approach is discussed to find the perturbed values on the base of the solution obtained. The Fourier variable separation method is used. The stresses are presented via harmonic functions. As a result magnetoelastic stresses are obtained in the closed form. Their distribution in the body is studied and some results of numerical calculations are shown. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Moment closure for FENE models of complex fluids
Authors: Du Qiang
Published: March 2008

In this talk, we present some joint work with current and former colleagues at Penn State (C. Liu, P. Yu and Y. Hyon) on moment closure approximations of multiscale complex fluid models. Moment closure not only provides a computationally feasible approach to simulate many multiscale phenomena but also offers insight to the understanding of the underlying physical processes. We will discuss some of our recent works on developing systematic moment closure models for micromacro FENE models of complex fluids and demonstrate their effectiveness for a wide range of parameter regimes. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A mesh adaptation for non‐stationary problems
Authors: Felcman Jiří , Kubera Petr
Published: March 2008

The subject‐matter of this paper is the numerical simulation of the multidimensional inviscid compressible transonic gas flow. An adaptive mesh is constructed in the framework of the ADER higher order cell‐centred finite volume scheme. An adaptation strategy based on the residual error indicator is followed by a recovery of the approximate solution on the new mesh. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Description of light focusing by a spherical lens using diffraction integral method
Authors: Guha Shekhar , Gonzalez Leonel P. , Sheng Qin
Published: March 2008

We describe here the propagation of light through a plano‐convex spherical lens using the Stratton‐Chu vector diffraction integrals. The values of the electric and magnetic fields on the two lens surfaces and at a point outside the lens are calculated by repeated use of the diffraction integrals and the intensity distribution in the focal region of the lens is determined. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Chemotoxicity recovery of mitochondria in non‐Hodgkin lymphoma resulting in minimal residual disease
Authors: Kusao Ian , Agsalda Melissa , Troelstrup David , Villanueva Nicolas , Shiramizu Bruce
Published: March 2008

Background

The mechanisms responsible for resistant disease or recurrence of non‐Hodgkin lymphoma (NHL) in children cover a wide spectrum from drug resistance to genetic mutations. A unique mechanism suggesting the role of mitochondria as the key energy source is studied following a clinical observation where pediatric Burkitt lymphoma (BL) specimens from patients on therapy were found to have increased copies of mitochondria DNA (mtDNA) in specimens which were shown to be positive for minimal residual disease and/or persistent disease (MRD/PD). This study hypothesized that the mitochondria play an important role in a cell's recovery from toxicity via a compensatory increase in mtDNA.

Procedure

BL specimens with MRD/PD were assayed for mtDNA. An in vitro model was then designed using Ramos cell lines by exposing the lymphoma cells to varying concentrations of doxorubicin and vincristine for 1 hr; and allowing for recovery in culture over 7 days. DNA was extracted from aliquots over several days to determine mtDNA copy numbers by real‐time polymerase chain reaction (PCR).

Results

Increased mtDNA copy numbers were found in clinical specimens with MRD/PD as well as in recovering Ramos cells from chemotoxicity.

Conclusions

The recovering lymphoma cells from the chemotoxic effects appeared to compensate by increasing mtDNA content, which may contribute to the clinical residual or resistant disease in some cases of childhood BL. Pediatr Blood Cancer 2008;51:193–197. © 2008 Wiley‐Liss, Inc.
Shwachman–Diamond syndrome presenting in a premature infant as pancytopenia
Authors: Black L. Vandy , Soltau Thomas , Kelly David R. , Berkow Roger L.
Published: March 2008

Shwachman–Diamond syndrome is a rare autosomal recessive disorder characterized by bone marrow dysfunction, exocrine pancreatic insufficiency, failure to thrive, and skeletal abnormalities. It is most commonly diagnosed in early childhood after the development of hematologic abnormalities. We report a premature infant born at 33 weeks gestation who was small for gestational age and displayed persistent cytopenias requiring transfusion. Genetic testing confirmed a diagnosis of Shwachman–Diamond syndrome (SDS). Pediatr Blood Cancer 2008;51:123–124. © 2008 Wiley‐Liss, Inc.
Antimicrobial prescribing trends in primary care: implications for health policy in Bahrain
Authors: Al Khaja Khalid A. J. , Sequeira Reginald P. , Damanhori Awatif H. H. , Ismaeel Abdulrahman Y. , Handu Shailendra S.
Published: March 2008

Purpose

To evaluate antimicrobial prescribing pattern by primary care physicians.

Methods

A nation‐wide, retrospective, multi‐centric prescription‐audit was carried out in primary care health centres in Bahrain.

Results

Systemic antimicrobials ranked the fourth most common class of drugs prescribed. Amoxycillin, cephalexin, erythromycin, ciprofloxacin and cotrimoxazole were prescribed by general practitioners (GPs) more often than by family physicians (FPs) (p < 0.05). With respect to prescribing of other antimicrobials and anthelmintic mebendazole, the differences between GPs and FPs were nonsignificant. Seventy‐seven per cent of systemic antimicrobials prescribed were for respiratory tract infections (RTIs). Topical antimicrobial preparations for ear and eye infections were prescribed by GPs in a rate significantly higher than by FPs (p < 0.05); of these, chloramphenicol and Locacorten vioform® (flumethasone +  clioquinol) ear drops and sulphacetamide eye drops were more often prescribed by GPs (p < 0.05). There were no significant differences in prescribing between GPs and FPs as regards topical antimicrobials used for oropharyngeal, skin and vulvovaginal infections.

Conclusion

Antimicrobials were extensively used in primary care, mainly for treating RTIs. The general practitioners were more avid prescribers of antimicrobials compared to the FPs. Rational use of antimicrobials in primary care should be encouraged and the reasons for the observed differences in prescribing of antimicrobials between the GPs and FPs need further evaluation. Copyright © 2008 John Wiley & Sons, Ltd.
Spirituality as a core domain in the assessment of quality of life in oncology
Authors: Whitford Hayley S. , Olver Ian N. , Peterson Melissa J.
Published: March 2008

Objectives: This study investigated including spiritual wellbeing as a core domain in the assessment of quality of life (QOL) in an Australian oncology population.

Methods: Four hundred and ninety consecutive cancer patients with mixed diagnoses completed the Functional Assessment of Chronic Illness Therapy—Spiritual Well‐Being (FACIT‐Sp) and the Mental Adjustment to Cancer (MAC) scale.

Results: Overall, 449 patients completed assessments. Spiritual wellbeing demonstrated a significant, positive association with QOL (r=0.59), fighting spirit (r=0.49) and a significant, negative relationship with helplessness/hopelessness (r=−0.47) and anxious preoccupation (r=−0.26). A hierarchical multiple regression showed spiritual wellbeing to be a significant, unique contributor to QOL beyond the core domains of physical, social/family, and emotional wellbeing (R2 change=0.08, p=0.000). However, high levels of meaning/peace or faith did not appear to significantly impact patients' ability to enjoy life despite chronic symptoms of pain or fatigue, making the current results inconsistent with other findings.

Conclusion: Results lend further support to the biopsychosocialspiritual model. By failing to assess spiritual wellbeing, the ‘true’ burden of cancer is likely to be miscalculated. However, at this stage, the exact clinical utility of spirituality assessment is unclear. Copyright © 2008 John Wiley & Sons, Ltd.
Effects of psychological distress on quality of life of adult daughters and their mothers with cancer
Authors: Kim Youngmee , Wellisch David K. , Spillers Rachel L.
Published: March 2008

Introduction: As the population continues to age, adult daughters are more likely to be involved in caregiving. Given the fact that sharing emotional experiences is common in female relationships, (dis)similarity between mothers with cancer and their adult caregiving daughters is expected. However, the extent to which the (dis)similarity in psychological distress influences the quality of life of each person remains unknown.

Method: This study aims at addressing this concern, using a total of 98 mother–daughter dyads participating in the American Cancer Society's Study of Cancer Survivors‐I and Quality of Life Survey for Caregivers.

Results: Using the Actor Partner Interdependence Model, the results showed that although each person's psychological distress is the strongest predictor of their own quality of life, a mother's distress also plays a significant role in the daughter's quality of life. Specifically, when mothers experienced greater levels of psychological distress, the daughters reported better mental health but poorer physical health.

Conclusions: Our findings on the disproportionately strong association between psychological distress of mothers with cancer and their adult caregiving daughters' quality of life suggest that caregiving daughters may benefit from programs designed to assist them to cope better with their mothers' psychological distress when both are living with cancer. Copyright © 2008 John Wiley & Sons, Ltd.
Surface Modification of Nafion Membranes Using Atmospheric‐Pressure Low‐Temperature Plasmas for Electrochemical Applications
Authors: Kim Jong Hoon , Sohn Juhee , Cho Jin Hoon , Choi Myeong Yeol , Koo Il Gyo , Lee Woong Moo
Published: March 2008

The surface morphology of a proton‐conducting polymer membrane is modified by plasma treatments in view of electrochemical applications. The atmospheric‐pressure glow plasmas generated using helium/hydrogen gas mixtures, or helium as the working gas are etching the surfaces very efficiently. The Nafion membranes placed between two dielectric disks undergo morphological, as well as surface chemical structural changes during exposure to the RF powered discharges. The change in the surface morphology depends on the composition of the plasma. The electrochemical cell employing the modified membrane as the electrolyte displays remarkable improvements in registering the current density.

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Catalytic effect of dissolved humic acids on the chemical degradation of phenylurea herbicides
Authors: Salvestrini Stefano , Capasso Sante , Iovino Pasquale
Published: March 2008

BACKGROUND:

Although biodegradation seems to be the main cause of herbicide degradation, abiotic degradation can also be important for chemicals such as phenylureas, which are subject to catalysed soil reactions. The aim of this work is to investigate the effect of dissolved humic acids (HAs), normally present in natural waters, on the hydrolysis of phenylurea herbicides, and it presents a kinetic model that takes into account the role of adsorption.

RESULTS:

The linearity of the adsorption isotherms indicates that phenylurea–humic acid interaction can be considered in terms of a repartition‐like equilibrium of phenylurea between water and HAs. Kinetic experiments show that the degradation rates of phenylureas increase with HA concentration.

CONCLUSION:

The kinetic equation adopted adequately describes the experimental data trend, allowing the evaluation of the catalytic effect of HAs on the chemical degradation of phenylureas. Carboxyl groups of HAs seem to play a leading role in the catalysis. The kinetic equation derived in this work could be helpful in predicting the persistence of phenylureas and of related compounds in natural water. Copyright © 2008 Society of Chemical Industry
Intermolecular band dispersion in highly ordered monolayer and multilayer films of pentacene on Cu(110)
Authors: Yamane Hiroyuki , Kawabe Eiji , Yoshimura Daisuke , Sumii Ryohei , Kanai Kaname , Ouchi Yukio , Ueno Nobuo , Seki Kazuhiko
Published: March 2008

We report the electronic structure and the charge transport mechanism of highly ordered films of pentacene on Cu(110) surface studied by angle‐resolved ultraviolet photoemission spectroscopy using synchrotron radiation. For a flat‐lying monolayer film, we observed the evidences of (i) formation of the interface states and (ii) two‐dimensional intermolecular band dispersion of the resultant interface states, which may originate from the hybridization between the molecular orbi‐tals and the wave function of the substrate. For an upright‐standing multilayer film, we observed the two‐dimensional intermolecular band dispersion, which originates from the intermolecular π–π interaction. The observed effective masses of the hole for different azimuths demonstrate the presence of the anisotropy of the hole mobility in pentacene crystals also at higher temperatures. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The propagation and diurnal cycles of deep convection in northern tropical Africa
Authors: Laing Arlene G. , Carbone Richard , Levizzani Vincenzo , Tuttle John
Published: March 2008

The propagation and diurnal cycle of organized convection in northern tropical Africa are examined using five years (1999–2003) of digital infrared imagery for May–August. Reduced‐dimension techniques are used to document the properties of cold clouds ‐ proxies for deep convection and precipitation. Large‐scale environments are diagnosed from global analyses.

Organized convection in Africa consists of coherent sequences or episodes which span an average distance of about 1000 km and last about 25 h. A substantial fraction of events exhibits systematic propagation at regional to continental scales while undergoing decay and regeneration. Episodes with 36 h duration and 1472 km span recur at a one‐per‐day interval. Most episodes have phase speed of 10–20 m s−1, which is faster than most African easterly waves. Convective episodes tend to initiate in the lee of high terrain, consistent with thermal forcing from elevated heat sources. Average diurnal frequency maxima result from the superposition of local diurnal maximum with the delayed‐phase arrival of systems propagating from the east. Propagation occurs with moderate low‐ to mid‐tropospheric shear, which varies with the African easterly jet migration and West African monsoon phases. Frequent deep convection occurs with local shear maxima near high terrain. For the peak monsoon period and for 10°W–10°E, where easterly waves and convective systems are frequent, 35% of cold cloud episodes occur east of the wave trough compared with about 24% to the west. Based on the coherent behaviour of organized, propagating convection, inferences may be made regarding the prediction of precipitation beyond one or two days. Copyright © 2008 Royal Meteorological Society
Bulk formulation of surface fluxes extended to weak‐wind stable conditions
Authors: Mahrt L.
Published: March 2008

The bulk formulation for surface fluxes based on surface‐layer similarity theory is found to be a poor approximation for weak‐wind stably‐stratified conditions. These conditions are often non‐stationary, with very weak turbulence, and have often been excluded from analysis. As a consequence of such exclusion and the failure to account for self‐correlation in the bulk aerodynamic formula for the surface stress, the validity of the similarity theory has been overestimated for weak‐wind stable conditions.

Four months of turbulence data from FLOSSII are analysed, in order to generalize the bulk formula to include the influence of the non‐stationary mesoscale motions on the generation of turbulence. The generalization of the bulk formula leads to a more systematic variation of the drag coefficient. Excluding cases of significant non‐stationarity of the wind field also leads to a more systematic behaviour of the drag coefficient, although it removes most of the very stable cases, thus introducing bias. Additional data are required in order to establish confidence in the generalized bulk formula. Copyright © 2008 Royal Meteorological Society
On the onset of bora and the formation of rotors and jumps near a mountain gap
Authors: Gohm Alexander , Mayr Georg J. , Fix Andreas , Giez Andreas
Published: March 2008

This study investigates the onset phase of a strong Adriatic bora windstorm that occurred on 4 April 2002. The target area is a gap about 20 km wide embedded in the coastal mountain barrier of the Dinaric Alps that favours strong jet‐like winds. Airborne‐aerosol back‐scatter lidar measurements on board the DLR Falcon research aircraft, together with surface and upper‐air observations, are used to verify high‐resolution numerical experiments conducted with the mesoscale atmospheric model RAMS and a single‐layer shallow‐water model (SWM). Especially during the breakthrough phase of the bora, the flow at the gap exit exhibits a complex spatial structure and temporal evolution. On a transect through the centre of the gap, a hydraulic jump forms; this is located close to the coast throughout the night, and starts to propagate downstream in the early morning. On a transect through the edge of the gap, a lee‐wave‐induced rotor becomes established, due to boundary‐layer separation. It starts to propagate downstream about two hours after the jump. This flow evolution implies that the onset of strong winds at the coast occurs several hours earlier downstream of the centre of the gap than downwind of the edge of the gap. Consequently, the wind field in the vicinity of Rijeka airport, located downwind of the gap, is strongly inhomogeneous and transient, and represents a potential hazard to aviation. Measured bora winds at the surface exceed 20 ms−1, and the simulated wind speed in the gap wind layer exceeds 30 ms−1. The simulated turbulent kinetic energy exceeds 10 m2 s−2.

RAMS indicates that wave‐breaking near a critical level is the dominant mechanism for the generation of the windstorm. Gap jets can be identified downstream of several mountain passes. The simulated wave pattern above the Dinaric Alps, the wave decay with height due to directional wind shear and the strong flow descent on the leeward side of the barrier are supported by measured back‐scatter intensities. Basic bora flow features, including gap jets and jumps, are remarkably well reproduced by SWM simulations. The RAMS reference run captures observed flow phenomena and the temporal flow evolution qualitatively well. A cold low‐level bias, an overestimated bora inversion strength, and a slightly too‐early bora onset are probably related to insufficient turbulent mixing in the boundary layer. The amplitude of trapped gravity waves, the time of the bora breakthrough and the inversion strength are found to be quite sensitive to the turbulence parametrization. Copyright © 2008 Royal Meteorological Society
Phase transformation induced by classical ion implantation in austenitic stainless steel
Authors: Dudognon J. , Vayer M. , Pineau A. , Erre R.
Published: March 2008

Structural modifications induced by Cr, Ar, N, Xe, Mo, Ag and Pb ion implantations in a 316LVM austenitic stainless steel within a 70‐nm thick surface layer were studied by grazing incidence X‐ray diffraction. In the implanted layer, austenite lattice expansion was first observed, then ferrite formation and in some cases amorphization. Atomic force microscopy (AFM) was used to study changes in surface topography under ion implantation: roughening, grain boundaries revelation, holes formation. Magnetic force microscopy (MFM) was used to distinguish on the surface ferrite domains when they were formed. Ferrite started to grow at grain boundaries and covered all the surface of the sample in some cases. A theoretical damage level was estimated using SRIM‐2003 computer program. The amount of ferrite and the amorphization rate were considered with respect to the damage level brought in the implanted layer by ion introduction. Existence of damage level thresholds for ferrite formation (200 displacements per atom (dpa)) and amorphization (400 dpa) were considered as evidence. These thresholds were independent of the nature of implanted element and the fluence of implantation. Copyright © 2008 John Wiley & Sons, Ltd.
Psychometric properties of a Persian language version of the Illness Attitude Scale in non‐clinical Iranian populations
Authors: Shaeiri Mohammad Reza , Atrifard Mahdieh , Asghari Ali
Published: March 2008

This paper examines the psychometric properties of a Persian language version of the Illness Attitude Scale (P‐IAS) in two Iranian student samples. After translation of the Illness Attitude Scale from English into Persian and pilot testing, the P‐IAS was used in two studies. In Study 1, the results of principal component analysis with oblique (Oblimin) rotation showed that five factors best explained the P‐IAS structure among 929 students. These factors were (1) fear of illness and disease; (2) frequency of treatment; (3) hypochondriacal beliefs and symptom effects; (4) health behaviours; and (5) thanatophobia. Cronbach's alpha, mean inter‐item correlations and test–retest coefficients showed that this solution was reliable. In Study 2, with a sample of 50 Iranian students, Pearson correlations were calculated between the five factors of the P‐IAS and somatization dimension of the revised Symptom Checklist 90. The results of the second study provided further support for the construct validity of the three factors of fear of illness and disease, frequency of treatment, and hypochondriacal beliefs and symptom effects. The authors suggest that the P‐IAS is sufficiently valid and reliable for clinical and research purposes in the Iranian population. Copyright © 2008 John Wiley & Sons, Ltd.
Implementation Matters: A Review of Research on the Influence of Implementation on Program Outcomes and the Factors Affecting Implementation
Authors: Durlak Joseph A. , DuPre Emily P.
Published: March 2008

The first purpose of this review was to assess the impact of implementation on program outcomes, and the second purpose was to identify factors affecting the implementation process. Results from over quantitative 500 studies offered strong empirical support to the conclusion that the level of implementation affects the outcomes obtained in promotion and prevention programs. Findings from 81 additional reports indicate there are at least 23 contextual factors that influence implementation. The implementation process is affected by variables related to communities, providers and innovations, and aspects of the prevention delivery system (i.e., organizational functioning) and the prevention support system (i.e., training and technical assistance). The collection of implementation data is an essential feature of program evaluations, and more information is needed on which and how various factors influence implementation in different community settings.
Phytoplankton stoichiometry
Authors: Klausmeier C. A. , Litchman E. , Daufresne T. , Levin S. A.
Published: March 2008

Because phytoplankton live at the interface between the abiotic and the biotic compartments of ecosystems, they play an important role in coupling multiple nutrient cycles. The quantitative details of how these multiple nutrient cycles intersect is determined by phytoplankton stoichiometry. Here we review some classic work and recent advances on the determinants of phytoplankton stoichiometry and their role in determining ecosystem stoichiometry. First, we use a model of growth with flexible stoichiometry to reexamine Rhee and Goldman's classic chemostat data. We also discuss a recent data compilation by Hall and colleagues that illustrates some limits to phytoplankton flexibility, and a model of physiological adaptation that can account for these results. Second, we use a model of resource allocation to determine the how the optimal nitrogen‐to‐phosphorus stoichiometry depends on the ecological conditions under which species grow and compete. Third, we discuss Redfield's mechanism for the homeostasis of the oceans’ nitrogen‐to‐phosphorus stoichiometry and show its robustness to additional factors such as iron‐limitation and temporal fluctuations. Finally, we suggest areas for future research.
Multifunctional Magnetic-fluorescent Nanocomposites for Biomedical Applications
Authors: Corr Serena A , Rakovich Yury P , Gun’ko Yurii K
Published: March 2008

Nanotechnology is a fast-growing area, involving the fabrication and use of nano-sized materials and devices. Various nanocomposite materials play a number of important roles in modern science and technology. Magnetic and fluorescent inorganic nanoparticles are of particular importance due to their broad range of potential applications. It is expected that the combination of magnetic and fluorescent properties in one nanocomposite would enable the engineering of unique multifunctional nanoscale devices, which could be manipulated using external magnetic fields. The aim of this review is to present an overview of bimodal “two-in-one” magnetic-fluorescent nanocomposite materials which combine both magnetic and fluorescent properties in one entity, in particular those with potential applications in biotechnology and nanomedicine. There is a great necessity for the development of these multifunctional nanocomposites, but there are some difficulties and challenges to overcome in their fabrication such as quenching of the fluorescent entity by the magnetic core. Fluorescent-magnetic nanocomposites include a variety of materials including silica-based, dye-functionalised magnetic nanoparticles and quantum dots-magnetic nanoparticle composites. The classification and main synthesis strategies, along with approaches for the fabrication of fluorescent-magnetic nanocomposites, are considered. The current and potential biomedical uses, including biological imaging, cell tracking, magnetic bioseparation, nanomedicine and bio- and chemo-sensoring, of magnetic-fluorescent nanocomposites are also discussed.
Flow cytometric cell cycle analysis of cultured brown bear fibroblast cells
Authors: Caamaño J.N. , Rodriguez A. , Salas A. , Muñoz M. , Diez C. , Prather R.S. , Gómez E.
Published: March 2008

The aim of this study was to assess by flow cytometry the cell cycle of brown bear fibroblast cells cultured under different growth conditions. Skin biopsies were taken in Cantabria (Spain) from a live, anaesthetized brown bear. DNA analysis was performed by flow cytometry following cell DNA staining with propidium iodide. Serum starvation increased (P < 0.01) the percentage of G0/G1 phase cells (92.7 ± 0.86) as compared to cycling cells (39.7 ± 0.86) or cells cultured to confluency (87.3 ± 0.86). DMSO included for 48 h in the culture significantly increased (P < 0.01) the percentage of G0/G1 phase of the cell cycle at all concentrations used and decreased percentages of S phase in a dose‐dependent fashion. Roscovitine increased the G0/G1 phase of the cell cycle (P < 0.01) at 15 μM concentration. Interestingly, the G2/M stage significantly increased at 30 and 50 μM compared to the control and 15 μM (P < 0.02). The cell cycle of brown bear adult fibroblast cells can be successfully synchronized under a variety of culture conditions.
Expression of glutamyl aminopeptidase by osteogenic induction in rat bone marrow stromal cells
Authors: Wu Yao , Xiao Jingang , Wu Ling , Tian Weidong , Liu Lei
Published: March 2008

Glutamyl aminopeptidase (GluAP, EC 3.4.11.7, ENPEP) is a 130‐kDa homodimeric zinc metallopeptidase which specifically cleaves the N‐terminal glutamate or aspartate residue of peptidic substrates such as cholecystokinin‐8 or angiotensin (Ang) II, in vitro. We used a DNA microarray hybridization (Genechip Rat Expression Array 230A, Affymetrix Inc., Santa Clara, CA, USA) to demonstrate that GluAP was upregulated in osteogenic induced rat bone marrow stromal cells (BMSCs). To compare the expression of GluAP in the osteogenic differentiation and non‐osteogenic differentiation of rat BMSCs in vitro, the cells were osteogenic induced in vitro. We also performed an MTT assay, alkaline phosphatase assay, alizarin red staining, and an immunohistochemical analysis to determine the osteogenic differentiation of BMSCs. The expression of GluAP was examined by real‐time polymerase chain reaction (PCR). The real‐time PCR results showed that GluAP was upregulated in osteogenic differentiated BMSCs in vitro, suggesting that GluAP may be correlated with the osteogenic differentiation of BMSCs.
The mechanism of myoblast deformation in response to cyclic strain—A cytomechanical study
Authors: Zheng Leilei , Song Jinlin , Li Zhihua , Fan Yubo , Zhao Zhihe , Chen Yangxi , Deng Feng , Hu Yun
Published: March 2008

Mechanical strain is one of the important epigenetic factors that cause deformation and differentiation of skeletal muscles. This research was designed to investigate how myoblast deformation occurs after cyclic strain loading. Myoblasts were passaged three times and harvested; various cyclic strains (2.5 kPa, 5 kPa and 10 kPa) were then loaded using a pulsatile mechanical system. The adaptive response of the myoblasts was observed at different time points (0.5 h, 1 h, 6 h and 12 h) post‐loading. At the early stage of cyclic strain loading (<1 h), almost no visible morphological changes were observed in the myoblasts. The actin cytoskeleton showed a disordered arrangement and a weak fluorescence expression; there was little expression of talin. At 6 h and 12 h post‐loading, the myoblasts changed their orientation to parallel (in the 2.5 kPa and 5 kPa groups) or perpendicular (in the 10 kPa group) to the direction of strain. Fluorescence expression of both the actin cytoskeleton and talin was significantly increased. The results suggest that cyclic strain has at least two ways to regulate adaptation of myoblasts: (1) by directly affecting actin cytoskeleton at an early stage post‐loading to cause depolymerization; and (2) by later chemical signals transmitted from the extracellular side to intracellular side to initiate repolymerization.
Overexpression of a TFIIIA‐type zinc finger protein gene ZFP252 enhances drought and salt tolerance in rice (Oryza sativa L.)
Authors: Xu Dong-Qing , Huang Ji , Guo Shu-Qiao , Yang Xia , Bao Yong-Mei , Tang Hai-Juan , Zhang Hong-Sheng
Published: March 2008

We previously identified a salt and drought stress‐responsive TFIIIA‐type zinc finger protein gene ZFP252 from rice. Here we report the functional analysis of ZFP252 using gain‐ and loss‐of‐function strategies. We found that overexpression of ZFP252 in rice increased the amount of free proline and soluble sugars, elevated the expression of stress defense genes and enhanced rice tolerance to salt and drought stresses, as compared with ZFP252 antisense and non‐transgenic plants. Our findings suggest that ZFP252 plays an important role in rice response to salt and drought stresses and is useful in engineering crop plants with enhanced tolerance to salt and drought stresses.
Reconstructing the single‐cell‐level behavior of a toggle switch from population‐level measurements
Authors: Tozaki Hirokazu , Kobayashi Tetsuya J. , Okano Hiroyuki , Yamamoto Ryo , Aihara Kazuyuki , Kimura Hidenori
Published: March 2008

Single‐cell‐level behaviors of cells are typically inferred from ensemble measurements. However, such inferences implicitly assume a biological version of ergodicity: the percentage of cells in a state is identical to the probability to find a cell in that state. While the ergodicity does not always hold, it has been rarely tested. Here, we reveal that the ergodicity does not necessarily hold even for simple toggle switches and that apparent stabilities of the switches are due to a balance between single‐cell‐level biased stabilities and growth rates differences. Therefore, verification of the ergodicity and reconstructing single‐cell‐level behaviors are crucial for understanding intracellular systems.
Resonance Raman spectroscopy can detect structural changes in haemozoin (malaria pigment) following incubation with chloroquine in infected erythrocytes
Authors: Webster Grant T. , Tilley Leann , Deed Samantha , McNaughton Don , Wood Bayden R.
Published: March 2008

Resonance Raman spectroscopy was applied to monitor the effects of chloroquine (CQ) treatment on cultures of Plasmodium falciparum trophozoites. A number of bands assigned to A1g and B1g modes characteristic of the haemozoin aggregate are reduced in intensity in the CQ‐treated cells, however, no bands from the CQ are observed. The intensity changes are attributed to intermolecular drug binding of the CQ in a sandwich type complex between ferriprotoporphyrin IX (FePPIX) dimer units. It is postulated that the CQ binds via π–π interactions between adjacent and orientated porphyrins thereby disrupting the haemozoin aggregate and reducing excitonic interactions between adjacent haems. The results show the potential of Raman microscopy as a screening tool for FePPIX:drug interactions in live cells.
Cell responses regulated by early reorganization of actin cytoskeleton
Authors: Papakonstanti E.A. , Stournaras C.
Published: March 2008

Microfilaments exist in a dynamic equilibrium between monomeric and polymerized actin and the ratio of monomers to polymeric forms is influenced by a variety of extracellular stimuli. The polymerization, depolymerization and redistribution of actin filaments are modulated by several actin‐binding proteins, which are regulated by upstream signalling molecules. Actin cytoskeleton is involved in diverse cellular functions including migration, ion channels activity, secretion, apoptosis and cell survival. In this review we have outlined the role of actin dynamics in representative cell functions induced by the early response to extracellular stimuli.
Post‐insult minocycline treatment attenuates hypoxia‐ischemia‐induced neuroinflammation and white matter injury in the neonatal rat: a comparison of two different dose regimens
Authors: Carty Michelle L. , Wixey Julie A. , Colditz Paul B. , Buller Kathryn M.
Published: March 2008

An increase in the number of activated microglia in the brain is a key feature of neuroinflammation after a hypoxic–ischemic insult to the preterm neonate and can contribute to white matter injury in the brain. Minocycline is a potent inhibitor of microglia and may have a role as a neuroprotective agent that ameliorates brain injury after hypoxia–ischemia in neonatal animal models. However to date large doses, pre‐insult administration and short periods of treatment after hypoxia–ischemia have mostly been investigated in animal models making it difficult to translate minocycline's potential applicability to protect the human preterm neonatal brain exposed to hypoxia–ischemia. We investigated whether repeated doses of minocycline can minimize white matter injury and neuroinflammation one week after hypoxia–ischemia (right carotid artery ligation and 30 min 6% O2) in the post‐natal day 3 rat pup. Two dosage regimens of minocycline were administered for one week; a high dose of 45 mg/kg 2 h after hypoxia–ischemia then 22.5 mg/kg daily or a low dose 22.5 mg/kg 2 h after hypoxia–ischemia then 10 mg/kg. Post‐natal day 3 hypoxia–ischemia significantly reduced myelin content, numbers of O1‐ and O4‐positive oligodendrocyte progenitor cells and increased activated microglia one week later on post‐natal day 10. The low dose minocycline regimen was as effective as the high dose in ameliorating neuroinflammation after post‐natal day 3 hypoxia–ischemia. However only the high dose regimen significantly attenuated reductions in O1‐ and O4‐positive oligodendrocyte progenitor cells and myelin content. The low dose only significantly attenuated the reduction in O1‐positive oligodendrocyte cell counts. Repeated, daily, post‐insult treatment with minocycline abolished neuroinflammation and may provide neuroprotection to white matter for up to one week after hypoxia–ischemia in a rodent preterm model. The present findings suggest the potential clinical relevance of a repeated, daily minocycline treatment strategy, administered after a hypoxia–ischemia insult, as a therapeutic intervention for hypoxia–ischemia‐affected preterm neonates.
Role of p38 MAPK and pro‐inflammatory cytokines expression in glutamate‐induced neuronal death of neonatal rats
Authors: Chaparro‐Huerta V. , Flores‐Soto M.E. , Gudiño‐Cabrera G. , Rivera‐Cervantes M.C. , Bitzer‐Quintero O.K. , Beas‐Zárate C.
Published: March 2008

Pro‐inflammatory cytokines TNF‐α, IL‐1β and IL‐6 rises significantly during neuronal damage and activate the signaling p38 MAPK pathway, which is involved in the apoptotic (AP) neuronal death. Systemic administration of glutamate as monosodium salt (MSG) to newborn animals induces neuronal death, however whether neurons die by AP or necrosis through MAPK p38 pathway activation it is unknown. In this study, TNF‐α, IL‐1β and IL‐6 expression levels, AP neuronal death and cellular type that produces TNF‐α was also identified in the cerebral cortex (CC) and striatum (St) of rats at 8, 10, and 14 days of age after neonatal exposure to MSG. TNF‐α production and AP neuronal death was significantly increased in the CC at PD8–10, and in the St in all ages studied by excitotoxicity effect induced with MSG. This effect was completely inhibited by SB203580 (p38 inhibitor) in both regions studied. TNF‐α, IL‐1β and IL‐6 RNAm increased after MSG administration, whereas SB203580 did not modify their expression. These data indicates that neuronal death induced by excitotoxicity appears to be mediated through p38 signaling pathway activated by TNF‐α and their inhibition may have an important neuroprotective role as part of anti‐inflammatory therapeutic strategy.
On equivalence of two approaches in index theory
Authors: Manuilov V.
Published: March 2008

The algebra Ψ(M) of order zero pseudodifferential operators on a compact manifoldMdefines a well-knownC*-extension of the algebraC(S*M) of continuous functions on the cospherical bundleS*M⊂T*Mby the algebra К of compact operators. In his proof of the index theorem, Higson defined and used an asymptotic homomorphismTfromC0(T*M) to К, which plays the role of a deformation for the commutative algebraC0(T*M). Similar constructions exist also for operators and symbols with coefficients in aC*-algebra. Recently we have shown that the image of the above extension under the Connes–Higson construction isTand that this extension can be reconstructed out ofT. That is why the classical approach to the index theory coincides with the one based on asymptotic homomorphisms. But the image of the above extension is defined only outside the zero section ofT*(M), so it may seem that the information encoded in the extension is not the same as that in the asymptotic homomorphism. We show that this is not the case.
INDECOMPOSABILITY GRAPHS OF RINGS
Authors: CVETKO-VAH KARIN , DOLŽAN DAVID
Published: March 2008

We define a subgraph of the zero divisor graph of a ring, associated to the ring idempotents. We study its properties and prove that for large classes of rings the connectedness of the graph is equivalent to the indecomposability of the ring and in those cases we also calculate the graph’s diameter.