bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantification of vitamin C in the rat brain in vivo using short echo‐time 1H MRS
Authors: Terpstra Melissa , Tkác̆ Ivan , Rao Raghavendra , Gruetter Rolf 
Published: April 2006

AbstractBoth ultrashort echo‐time STEAM and MEGA‐PRESS‐edited spectroscopy were used to validate noninvasive quantification of vitamin C (ascorbate) in the developing rat brain, where changes in ascorbate concentration have been reported. Despite strong overlap with resonances from glutamine, glutamate, glutathione, and macromolecules, reliable quantification of ascorbate (Cramer‐Rao lower bounds < 0.2 μmol/g) by LCModel analysis of STEAM (TE = 2 ms) spectra was possible at 9.4 T. Ascorbate concentrations quantified from the STEAM spectra were in very good agreement with concentrations calculated from fully resolved ascorbate resonances in MEGA‐PRESS‐edited spectra measured from identical volumes of interest. Ascorbate concentrations measured using STEAM decreased with increasing postnatal rat age, in agreement with published brain ascorbate concentrations measured in vitro using high‐performance liquid chromatography (HPLC). Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Advantages of parallel imaging in conjunction with hyperpolarized helium—A new approach to MRI of the lung
Authors: Lee Ray F. , Johnson Glyn , Grossman Robert I. , Stoeckel Bernd , Trampel Robert , McGuinness Georgeann 
Published: April 2006

AbstractHyperpolarized helium (3He) gas MRI has the potential to assess pulmonary function. The non‐equilibrium state of hyperpolarized 3He results in the continual depletion of the signal level over the course of excitations. Under non‐equilibrium conditions the relationship between the signal‐to‐noise ratio (SNR) and the number of excitations significantly deviates from that established in the equilibrium state. In many circumstances the SNR increases or remains the same when the number of data acquisitions decreases. This provides a unique opportunity for performing parallel MRI in such a way that both the temporal and spatial resolution will increase without the conventional decrease in the SNR. In this study an analytical relationship between the SNR and the number of excitations for any flip angle was developed. Second, the point‐spread function (PSF) was utilized to quantitatively demonstrate the unconventional SNR behavior for parallel imaging in hyperpolarized gas MRI. Third, a 24‐channel (24ch) receive and two‐channel (2ch) transmit phased‐array system was developed to experimentally prove the theoretical predictions with 3He MRI. The in vivo experimental results prove that significant temporal resolution can be gained without the usual SNR loss in an equilibrium system, and that the entire lung can be scanned within one breath‐hold (∼13 s) by applying parallel imaging to 3D data acquisition. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Linear combination filtering for T2‐selective imaging of the knee
Authors: Vidarsson Logi , Gold Garry E. , Hargreaves Brian , Pauly John M. 
Published: April 2006

AbstractRecently a novel T2 selective imaging method based on linear combination (LC) filtering was developed. By linearly combining images acquired with different echo times LC filtering is able to generate images showing only tissues with a preselected range of T2 relaxation times. In this study the use of LC filtering in knee imaging was investigated. Three LC filters were designed: a short LC filter for imaging the knee meniscus, a medium LC filter for articular cartilage, and a long LC filter for synovial fluid. To verify the filter designs, eight phantoms with different T2 relaxation times were imaged. In addition, in vivo images were acquired from four asymptomatic volunteers and a subject with cartilage damage. T2 maps were also generated using the same source images. Signal‐to‐noise ratio (SNR) measurements were made of the meniscus, cartilage, and fluid regions on the three LC filtered images. The highest SNR was seen in the target tissue on each of the LC filtered images. LC filtering is a new method that can selectively image knee tissues based on their T2. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Elasto‐plastic finite element analysis of shells with damage due to microvoids
Authors: Woelke Pawel , Voyiadjis George Z. , Perzyna Piotr 
Published: April 2006

AbstractThis paper presents a non‐linear finite element analysis for the elasto‐plastic behaviour of thick/thin shells and plates with large rotations and damage effects. The refined shell theory given by Voyiadjis and Woelke (Int. J. Solids Struct.2004;41:3747–3769) provides a set of shell constitutive equations. Numerical implementation of the shell theory leading to the development of theC0quadrilateral shell element (Woelke and Voyiadjis, Shell element based on the refined theory for thick spherical shells. 2006, submitted) is used here as an effective tool for a linear elastic analysis of shells. The large rotation elasto‐plastic model for shells presented by Voyiadjis and Woelke (General non‐linear finite element analysis of thick plates and shells. 2006, submitted) is enhanced here to account for the damage effects due to microvoids, formulated within the framework of a micromechanical damage model. The evolution equation of the scalar porosity parameter as given by Duszek‐Perzyna and Perzyna (Material Instabilities:Theory and Applications,ASME Congress, Chicago, AMD‐Vol. 183/MD‐50, 9–11 November 1994; 59–85) is reduced here to describe the most relevant damage effects for isotropic plates and shells, i.e. the growth of voids as a function of the plastic flow. The anisotropic damage effects, the influence of the microcracks and elastic damage are not considered in this paper. The damage modelled through the evolution of porosity is incorporated directly into the yield function, giving a generalized and convenient loading surface expressed in terms of stress resultants and stress couples. A plastic node method (Comput. Methods Appl. Mech. Eng.1982;34:1089–1104) is used to derive the large rotation, elasto‐plastic‐damage tangent stiffness matrix. Some of the important features of this paper are that the elastic stiffness matrix is derived explicitly, with all the integrals calculated analytically (Woelke and Voyiadjis, Shell element based on the refined theory for thick spherical shells. 2006, submitted). In addition, a non‐layered model is adopted in which integration through the thickness is not necessary. Consequently, the elasto‐plastic‐damage stiffness matrix is also given explicitly and numerical integration is not performed. This makes this model consistent mathematically, accurate for a variety of applications and very inexpensive from the point of view of computer power and time. Copyright © 2006 John Wiley & Sons, Ltd.
The potential role of occupational therapy in acute care with clients with HIV/AIDS
Authors: Fish Gillian , Rudman Deborah Laliberte 
Published: April 2006

AbstractAs medical interventions aimed at prolonging the lives of people with Human Immunodeficiency Virus (HIV) and Acquired Immunodeficiency Syndrome (AIDS) are implemented, HIV/AIDS is evolving into a chronic disease with associated disability. People with HIV/AIDS can experience numerous occupational performance problems and occupational therapists need to examine and develop their role in helping to meet the needs of this population. Acute‐care occupational therapists work with clients with HIV/AIDS who experience multiple admissions and who present with varying levels of occupational function. This paper outlines the potential role of occupational therapy in acute care with clients with HIV/AIDS using the Model of Occupational Performance (Canadian Association of Occupational Therapists, 1991) as a conceptual framework. The results of a retrospective chart review that investigated the role of two occupational therapists working with clients with HIV/AIDS in an acute‐care setting are presented and compared with the potential role. Practice and research recommendations to address the discrepancies between the potential and present role are presented. Copyright © 1998 Whurr Publishers Ltd.
Understanding assessment concepts within the occupational therapy context
Authors: Clemson Lindy , Fitzgerald Maureen H. 
Published: April 2006

AbstractThis paper explores therapists' perceptions about issues of validity, reliability and usefulness of assessment tools. It draws on the findings of a qualitative inquiry that was designed to evaluate the usefulness of the Westmead Home Safety Assessment. The study also explored therapists attitudes and beliefs about reliability, validity and related concepts, and how they understand and use these concepts in practice. In‐depth, semi‐structured interviews and participant‐observations were conducted. The findings suggest that issues of reliability and validity were not clearly understood, terms were confused and therapists had difficulty in applying the concepts in their practice. Reliability was viewed as important but much less attention was given to validity. By not understanding validity, therapists may not give themselves credit where it is due, lack confidence in their assessments and their ability, and, therefore, may not always use tools to their best advantage. Copyright © 1998 Whurr Publishers Ltd.
Supervising students: exploring the experience through reflective journals
Authors: Jung Bonny , Tryssenaar Joyce 
Published: April 2006

AbstractFieldwork is a vital component of undergraduate occupational therapy education and is dependent on effective clinical educators. This study explored the lived experience of clinical preceptors, through an interpretive approach. Thirteen clinical preceptors kept reflective journals during a six‐week fieldwork experience. Data were analysed using an inductive retrospective content analysis of the journals. Results included the anticipation related to preparing for the students, self‐doubt about personal abilities; preparation and organization for the student; the time consuming nature of the task; balancing workload demands; personal enjoyment and rewards from the experience; desire for a positive experience to validate personal skill level; and closure reaction. The themes were consistent across the majority of the journals. Isolated therapists reported a collegial benefit from student supervision. The results may be helpful in connecting continuing education opportunities with preceptors' needs and in the orientation of new preceptors. Copyright © 1998 Whurr Publishers Ltd.
Creative arts in occupational therapy: ancient history or contemporary practise?
Authors: Thompson Melanie , Blair Sheena E.E. 
Published: April 2006

AbstractThis paper is primarily concerned with the use of creative arts by occupational therapists in adult mental health rehabilitation. A review of relevant literature within and beyond occupational therapy suggests that creative arts have therapeutic value. The first section considers the more traditional, psychodynamic framework for creative arts in mental health. This underpinned much therapeutic creative art work between the 1960s and 1980s. The second section draws on a broader, more eclectic framework of theorising and research. This offers a rationale for the use of creative arts in their own therapeutic right. It is hoped that this will stimulate thinking among occupational therapists about retaining and promoting creative arts within their practice. Copyright © 1998 Whurr Publishers Ltd.
Pilot study of the inpatient rehabilitation – scales of therapeutic occupation
Authors: Sass Pamela L. , Nelson David L. 
Published: April 2006

AbstractThe IR – SOTO is a self‐help instrument that assists the occupational therapist in evaluating the adherence of an inpatient rehabilitation facility to an occupational approach to therapy. The IR – SOTO focuses on individualization of therapy, holism, naturalistic occupations, documentation of occupation and communication of occupational therapy principles. A series of practitioner panels provided feedback on the content validity of early versions of the instrument. Pilot testing of the revised instrument (a 62‐item survey using seven‐point Likert scales) was carried out using a mailed survey (n = 138) to nine inpatient rehabilitation facilities in different areas of the United States. The pilot version of the IR–SOTO was internally consistent, with alpha = 0.91. The overall mean score across items and across subjects of 5.48 on a seven‐point scale (sd = 0.52) indicates some adherence to an occupational approach to therapy. The scores of one facility were significantly lower than five of the other facilities. Continued revision of the instrument to enhance reliability and validity is recommended, with testing of test–retest reliability as a priority. The IR–SOTO holds promise for measuring a facility's approach to the use of occupation as therapy in inpatient rehabilitation. Copyright © 1998 Whurr Publishers Ltd.
Heat and fire resistance of polyurethane‐polydimethylsiloxane hybrid material
Authors: Belva Frederic , Bourbigot Serge , Duquesne Sophie , Jama Charaf , Le Bras Michel , Pelegris Christine , Rivenet Murielle 
Published: April 2006

AbstractThis work examines the synthesis of polyurethane (PU)—polydimethylsiloxane (PDMS) hybrid in order to provide low flammability to PU. Chemical characterization of PU/PDMS hybrid by solid state NMR of carbon and FT‐IR shows that some PDMS segments are incorporated in the macromolecular chains of PU. Heat stability of PU (thermo‐oxidative decomposition) is not enhanced by the incorporation of PDMS except that the amount of the high temperature residue is improved and depends on the amount of PDMS incorporated in the PU chains. It is explained by the formation and the accumulation of silica. On the contrary, thermal stabilization (charring) occurs in the pyrolytic conditions when incorporating PDMS. The accumulation of silica as well as charring enhancement enables the flammability properties of the PU/PDMS hybrid to form a protective layer limiting heat transfer between the flame and the substrate. The heat release rate measured by cone calorimetry of PU/PDMS hybrid is significantly decreased compared to virgin PU and temperature of the back of the sample is comparatively low compared to virgin PU. Copyright © 2006 John Wiley & Sons, Ltd.
Complex activity of clay and CNT particles in flame retarded EVA copolymer
Authors: Marosfői B. B. , Marosi Gy. J. , Szép A. , Anna P. , Keszei S. , Nagy B. J. , Martvonova H. , Sajó I. E. 
Published: April 2006

AbstractInterface modifications optimized for fire retardancy require detailed research. Confocal Raman microscopy was used to analyze the degradation locally in the area of the nanotube and clay additives. The double‐walled carbon nanotube (DWCNT), containing Co catalyst residue, accelerates the deacetylation process of poly(ethylene‐co‐vinylacetate) (EVA) considerably, while the montmorillonite (MMT) has no significant influence under static circumstances. The compounding process influences the effect of MMT, which causes partial crosslinking in EVA during the compounding. This mechanochemical reaction is catalyzed by uncovered MMT particles, while organophillized MMT promotes the charring process. Inorganic surface modification with various metal ions has also some stabilizing effect. Spray drying of MMT results in microparticles of increased surface area and improved thermal stability of the EVA system. The lowest rate of flame spreading was achieved using uncoated MMT, while coating with cationic surfactant was most efficient for hindering dripping. The rate of heat release (RHR) of the organically modified and the spray dried MMT was approximately the same. The combined organic‐inorganic modified clay moderates both the dripping and the flame spreading in the EVA. Copyright © 2006 John Wiley & Sons, Ltd.
Use of prescription medications with a potential for fetal harm among pregnant women
Authors: Andrade Susan E. , Raebel Marsha A. , Morse Abraham N. , Davis Robert L. , Chan K. Arnold , Finkelstein Jonathan A. , Fortman Kris K. , McPhillips Heather , Roblin Douglas , Smith David H. , Yood Marianne Ulcickas , Platt Richard , Gurwitz Jerry H. 
Published: April 2006

AbstractPurposeTo estimate the prevalence of use of prescription drugs with a potential for fetal harm among pregnant women in the United States.MethodsA retrospective study was conducted using the automated databases of eight health maintenance organizations involved in the HMO Research Network Center for Education and Research on Therapeutics (CERT). Women who delivered an infant from January 1996 to December 2000 were identified. The frequency of use of prescription drugs with a potential for fetal harm was based upon the expert review of a clinical teratologist and the U.S. Food and Drug Administration (FDA) risk classification system, assuming a gestational duration of 270 days.ResultsAmong the 114 165 women with no documentation of a diagnosis suggesting potential pre‐term birth or dispensing of ovulation stimulants in the 270 days before delivery, 1305 (1.1%) received a teratogenic drug during the 270 days before delivery, based upon the expert review of a clinical teratologist. A larger proportion of women received U.S. FDA category D or X drugs (5.8%; N = 6600). However, the general patterns of use were similar, with higher use in early pregnancy compared to later trimesters. The proportion of women dispensed a teratogen during pregnancy was substantially higher among women who received a teratogen in the 90 days before pregnancy compared to women who did not (adjusted RR = 38.9, 95%CI, 33.5, 45.3).ConclusionsOur results suggest that further efforts directed at physicians to counsel women or at the women themselves about the potential risks of particular medications appear warranted. Copyright © 2006 John Wiley & Sons, Ltd.
Initial non‐compliance with antihypertensive monotherapy is followed by complete discontinuation of antihypertensive therapy
Authors: Van Wijk Boris L.G. , Klungel Olaf H. , Heerdink Eibert R. , de Boer Anthonius 
Published: April 2006

AbstractPurposeDiscontinuation with treatment is a major problem in the treatment of hypertension. The objective of our study was to assess the association between non‐compliance and discontinuation in patients who started using antihypertensive monotherapy.MethodsA nested case‐control study within a cohort of new users of antihypertensive drugs between 1st January 1999 and 31st December 2002 was performed. We used data from the PHARMO database, a record linkage system containing drug‐dispensing records from community pharmacies and linked hospital discharge records of approximately 950,000 subjects. Cases discontinued their use of antihypertensive monotherapy and were not switched to other antihypertensive treatment, controls stayed on their initially prescribed monotherapy. Conditional logistic regression was used to calculate odds ratios (OR) and their 95% confidence intervals (CI).ResultsIn a cohort of 39,714 new users of antihypertensive drugs, we identified 9111 cases and 9111 matched controls. The percentage of non‐compliant patients (compliance <80%) among cases and controls was 14.0% and 5.8%, respectively [OR 2.86 (95%CI: 2.52–3.24)]. Patients who used less than 90 days had a higher risk on discontinuation [OR 3.10 (95%CI: 2.67–3.59)] than patients who used more than 90 days [OR 2.28 (95%CI: 1.79–2.92)]. The association was generally similar among males and females, among the different types of antihypertensives and among the different age groups.ConclusionIn patients who start antihypertensive monotherapy, non‐compliance is often followed by discontinuation of this antihypertensive treatment. The pharmacy medication history is a valuable tool for physicians to identify patients who have a high risk on discontinuation with antihypertensive treatment. Copyright © 2006 John Wiley & Sons, Ltd.
Factors associated with the pharmacist counselling without dispensing
Authors: Caamaño Francisco , Tomé‐Otero Manuel , Takkouche Bahi 
Published: April 2006

AbstractPurposeTo describe the pharmacist counselling without dispensing and to analysed the characteristics of pharmacies and pharmacists that provide this type of counselling, and the characteristics of customers that receive it to a greater extent.MethodsWe carried out a cohort study on a sample of 166 pharmacists in North West Spain. Different characteristics of pharmacists and clients and other variables related to counselling were measured (who initiates the consultation; type of consultation; whether or not the patient consulted with a doctor previously and who is the receptor of the counselling) were included in the models as independent variables. Pharmacist Counselling without dispensing (PhCwD) were included as dependent variable. We constructed logistic regression models.ResultsThe response rate to the first questionnaire was 98.8% and the participation rate in the follow‐up was 60%. Out of 7010 registered pharmacist counselling, 6034 were included in the final analysis (86.1%). The proportion of PhCwD is 26.3% (95%IC: 25.2–27.4).ConclusionsOur results show the number of working hours of the pharmacist and the amount of customers are associated with PhCwD. So working hours and amount customers should be reduced. Other factor that should be taken into account is the fact that pharmacists with less experience should give less counsels. Thus during the university period pharmacist counselling should be studied. Finally, our results show that an important proportion of counselling is given regardless the dispensation process, and this should be taken into account when defining the pharmacists remuneration system. Copyright © 2006 John Wiley & Sons, Ltd.
Optimization of opto‐electronic property and device efficiency of polyfluorenes by tuning structure and morphology
Authors: Chen Peng , Yang Guizhong , Liu Tianxi , Li Tingcheng , Wang Min , Huang Wei 
Published: April 2006

AbstractPolyfluorene‐based oligomers and polymers (PFs) have been studied intensively as active materials for organic optoelectronic devices. In this review, the optimization of the opto‐electronic property and device efficiency of polyfluorenes in the field of light‐emitting diodes (LEDs) and photovoltaic cells (PVs) by tuning structure and morphology are summarized in terms of two typical modification techniques: copolymerization and blending. The relationships between molecular structures, thin film morphologies, opto‐electronic properties and device efficiencies are discussed, and some recent progress in LEDs and PVs is simultaneously reviewed. After the introduction, the basic knowledge of molecular structures and properties of polyfluorene homopolymers is presented as a background for a better understanding of their great potential for opto‐electronic applications. Immediately after this, three different opinions on the origin of low‐energy emission band at 520–540 nm in polyfluorene‐based LEDs are addressed. Rod–coil block copolymers and alternative copolymers are focused on in the next section, which are a vivid embodiment of controlling supramolecular structures and tailoring molecular structures, respectively. In particular, various supramolecular architectures induced by altering coil blocks are carefully discussed. Recent work that shows great improvement in opto‐electronic properties or device performance by blending or doping is also addressed. Additionally, the progress of understanding concerning the mechanisms of exciton dynamics is briefly referred to. Copyright © 2006 Society of Chemical Industry