bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and characterization of core–shell‐type polymeric micelles from diblock copolymers via reversible addition–fragmentation chain transfer
Authors: Zhang Ping , Liu Qunfeng , Qing Aixiang , Shi Jianbo , Lu Mangeng 
Published: March 2006

AbstractA method was developed to enable the formation of nanoparticles by reversible addition–fragmentation chain transfer polymerization. The thermoresponsive behavior of polymeric micelles was modified by means of micellar inner cores and an outer shell. Polymeric micelles comprising AB block copolymers of poly(N‐isopropylacrylamide) (PIPAAm) and poly(2‐hydroxyethylacrylate) (PHEA) or polystyrene (PSt) were prepared. PIPAAm‐b‐PHEA and PIPAAm‐b‐PSt block copolymers formed a core–shell micellar structure after the dialysis of the block copolymer solutions in organic solvents against water at 20 °C. Upon heating above the lower critical solution temperature (LCST), PIPAAm‐b‐PHEA micelles exhibited an abrupt increase in polarity and an abrupt decrease in rigidity sensed by pyrene. In contrast, PIPAAm‐b‐PSt micelles maintained constant values with lower polarity and higher rigidity than those of PIPAAm‐b‐PHEA micelles over the temperature range of 20–40 °C. Structural deformations produced by the change in the outer polymer shell with temperature cycles through the LCST were proposed for the PHEA core, which possessed a lower glass‐transition temperature (ca. 20 °C) than the LCST of the PIPAAm outer shell (ca. 32.5 °C), whereas the PSt core with a much higher glass‐transition temperature (ca. 100 °C) retained its structure. The nature of the hydrophobic segments composing the micelle inner core offered an important control point for thermoresponsive drug release and the drug activity of the thermoresponsive polymeric micelles. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3312–3320, 2006
Synthesis of amphiphilic star block copolymers via diethyldithiocarbamate‐mediated living radical polymerization
Authors: Ishizu Koji , Katsuhara Hideya , Itoya Kazuo 
Published: March 2006

Abstract(AB)f star block copolymers were synthesized by the radical polymerization of a poly(t‐butyl acrylate)‐block‐poly(methyl methacrylate) diblock macroinitiator with ethylene glycol dimethacrylate in methanol under UV irradiation. Diblock macroinitiators were prepared by diethyldithiocarbamate‐mediated sequential living radical copolymerization initiated by (4‐cyano‐4‐diethyldithiocarbamyl)pentanoic acid under UV irradiation. The arm number (f) was controlled by the variation of the initial concentration of the diblock initiator. It was found from light scattering data that such star block copolymers (f ≥ 344) not only took a spherical shape but also formed a single molecule in solution. Subsequently, we derived amphiphilic [arm: poly(acrylic acid)‐block‐poly(methyl methacrylate)] star block copolymers by the hydrolysis of poly(t‐butyl acrylate) blocks. These amphiphilic star block copolymers were soluble in water because the external blocks were composed of hydrophilic poly(acrylic acid) chains. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3321–3327, 2006
Synthesis of metal (Fe or Pd)/alloy (Fe–Pd)‐nanoparticles‐embedded multiwall carbon nanotube/sulfonated polyaniline composites by γ irradiation
Authors: Reddy Kakarla Raghava , Lee Kwang‐Pill , Gopalan Anantha Iyengar , Kim Min Seok , Showkat Ali Md , Nho Young Chang 
Published: March 2006

AbstractComposites of multiwall carbon nanotubes (MWCNTs) and sulfonated polyaniline (SPAN) were prepared through the oxidative polymerization of a mixture of aniline, 2,5‐diaminobenzene sulfonic acid, and MWCNTs. Fe, Pd, or Fe–Pd alloy nanoparticles were embedded into the MWCNT–SPAN matrix by the reduction of Fe, Pd, or a mixture of Fe and Pd ions with γ radiation. Sulfonic acid groups and the emeraldine form of backbone units in SPAN served as the source for the reduction of the metal ions in the presence of γ radiation. The existence of metallic/alloy particles in the MWCNT–SPAN matrix was further ascertained through characterization by high‐resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, thermogravimetric analysis, and conductivity measurements. HRTEM pictures clearly revealed the existence of Fe, Pd, and Fe–Pd nanoparticles of various sizes in the MWCNT–SPAN matrices. There were changes in the electronic properties of the MWCNT–SPAN–M composites due to the interaction between the metal nanoparticles and MWCNT–SPAN. Metal‐nanoparticle‐loaded MWCNT–SPAN composites (MWCNT–SPAN–M; M = Fe, Pd, or Fe–Pd alloy) showed better thermal stability than the pristine polymers. The conductivity of the MWCNT–SPAN–M composites was approximately 1.5 S cm−1, which was much higher than that of SPAN (2.46 × 10−4 S cm−1). Metal/alloy‐nanoparticle‐embedded, MWCNT‐based composite materials are expected to find applications in molecular electronics and other fields. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3355–3364, 2006
Quantification of branching in disordered materials
Authors: Kulkarni A. S. , Beaucage G. 
Published: March 2006

AbstractThe phenomenon of structural branching is ubiquitous in a wide array of materials: polymers, ceramic aggregates, polymeric networks, and gels. Branching has a strong influence on the structure–property relationships of these materials. Despite the interdisciplinary importance and decades of effort, the analytical description and quantification of branching are weak. Existing techniques for polymers based on size exclusion chromatography and rheology are, at best, qualitative, and quantitative characterization techniques such as nuclear magnetic resonance spectroscopy and transmission electron microscopy (for ceramic aggregates) have limitations in providing routine quantification. For ceramic aggregates, theoretical work has dominated, and only a few publications on analytical studies exist to support the theory. Small‐angle scattering of X‐rays and neutrons can be used to quantify the branch content through application of concepts native to fractal geometry. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1395–1405, 2006
Pyrotechnic and Thermal Studies on the Magnesium‐Strontium Nitrate Pyrotechnic System
Authors: Tuukkanen Irmeli M. , Charsley Edward L. , Laye Peter G. , Rooney James J. , Griffiths Trevor T. , Lemmetyinen Helge 
Published: March 2006

AbstractThe pyrotechnic and thermal properties of a range of binary magnesium‐strontium nitrate compositions containing from 10% to 90% by mass of magnesium have been determined. The burning rate and light output were measured after consolidating the compositions into cardboard tubes. The exothermicity, temperature of ignition and time to ignition of the compositions were also determined and the products of combustion were characterized.
Redefining ‘doing something’: health professionals' views on their role in the care of stroke patients
Authors: Pound Pandora , Ebrahim Shah 
Published: March 2006

AbstractStroke has traditionally been considered, both by lay people and by many people working within the health services, to be a tragic yet essentially uninteresting condition, possibly because of its associations with old age, chronicity and the widespread perception that very little can be done about it. This study explored health professionals' views about their role in caring for people with stroke, and about what they gained from and contributed to this work. Questionnaires were distributed to staff working on an elderly care unit, a general medical ward and a stroke unit. Nurses and physiotherapists were positive and reported that they had much to offer people with stroke, and many rewards to gain from their work. Occupational therapists reported that in theory they had much to contribute to people with stroke, but in practice lack of resources and staff shortages prevented them from fulfilling their potential. Speech therapists also complained of scarce resources, and of a lack of recognition of their specialty, but felt able to contribute to improving peoples' quality of life. Both psychologists reported that their work with people with stroke was satisfying and stimulating. However, with the exception of the consultant on the stroke unit, doctors reported feeling they had little to offer, and little to gain from working with people with stroke. Therapists on the elderly care unit, and speech therapists in all settings reported difficulties within the multidisciplinary team. Although each profession had different concerns and priorities, the majority seemed to have a positive approach to their work with people with stroke. Similarly, the majority reported that the best thing about their work was when people recovered, although professions defined recovery differently. Copyright © 1997 Whurr Publishers Ltd.
The assessment of functional ability in patients with Parkinson's disease: The PLM‐test and three clinical tests
Authors: Kokko Satu‐Mari , Paltamaa Jaana , Ahola Erja , Mälkiä Esko 
Published: March 2006

AbstractThis study assesses functional ability of Parkinson's disease (PD) patients by means of an objective movement analysis (the PLM‐test) and three clinical tests. The correlation between the tests was also studied. The main object of this study was to detect and measure relevant disabilities in Parkinson's disease to obtain a clinical test battery. Copyright © 1997 Whurr Publishers Ltd.
Admission interviews: questions of utility and cost in masters of physical therapy programs in the United States
Authors: Gabard Donald L , Porzio Rochelle , Oxford Toni , Braun Robert 
Published: March 2006

AbstractPurposeThe purpose of this research was twofold. The first purpose was to assess the predictive validity of the interview process in student completion of entry level Masters of Physical Therapy programs on the conventional schedule for the university. The second was to provide a descriptive study of interview formats currently used by these institutions and the cost to the institution, estimated by hours of labor used exclusively for the interview process.MethodA questionnaire was mailed to the Director of Admissions of 63 accredited Masters of Physical Therapy programs in the United States. Forty‐three responded to the questionnaire for a response rate of 68.3%. Twenty‐eight programs (65.1%) performed interviews and fifteen (34.9%) programs did not.ResultsA two‐tailed t‐test revealed that no significant difference existed between programs that interview and those that did not with regards to the attrition rate of students. There was great diversity between the programs in interview content and structure. The cost to the institutions in terms of hours averaged 261 hours per school for faculty and support staff combined.ConclusionThe schools of physical therapy that award the Masters of Physical Therapy degree vary markedly in the interview content and format both between schools and with recommendations known to enhance validity and reliability. Since, no difference exists in attrition of students between schools that interview and those that do not, the expense and time invested by both the institution and the students are important considerations. The findings of this study indicate the need for continued investigation of the effectiveness of the interview process and alternative methods of valid and reliable student selection. Copyright © 1997 Whurr Publishers Ltd.
Respiratory muscle activity and pulmonary function during acutely induced airways obstruction
Authors: van der Schans Cees P , de Jong Wietze , de Vries Gerrie , Postma Dirkje S , Koëter Gerard H , van der Mark Thomas W 
Published: March 2006

AbstractBackgroundPatients with airway obstruction may spontaneously breathe with a positive expiratory pressure by pursing their lips during expiration, especially in case of dyspnea. Dyspnea seems to be related to increased activity of the respiratory muscles. A potential explanation for the use of pursed lips breathing (PLB) is that this type of breathing leads to a reduction of respiratory muscle activity. The purpose of this study was to assess the effect of breathing with a positive expiratory pressure of 5cm H2O, simulating pursed lips breathing (SPLB), on respiratory muscle activity and pulmonary function during induced airway obstruction.MethodsIn twelve asthmatic patients, tonic and phasic electromyographic (EMG) activity of the following muscles was obtained: scalene muscle, parasternal muscle, and abdominal muscles. Pulmonary function and EMG measurements were performed before and after propranolol induced airway obstruction.ResultsSimulated pursed lips breathing resulted in a significant increase of functional residual capacity and tidal volume both at baseline and during airway obstruction. Phasic respiratory muscle activity during PEP breathing increased especially at baseline. We conclude that beneficial effects of breathing with a positive expiratory pressure of 5cm H2O, which is similar to pursed lips breathing, cannot be explained by changes in respiratory muscle activity or pulmonary function. Copyright © 1997 Whurr Publishers Ltd.
Deep defect related photoluminescence in heavily doped CuGaTe2 crystals
Authors: Jagomägi Andri , Krustok Jüri , Grossberg Maarja , Danilson Mati , Raudoja Jaan 
Published: March 2006

AbstractCuGaTe2 samples very often exhibit optical and electrical properties of heavily doped semiconductors. This paper investigates the low temperature photoluminescence properties of polycrystalline CuGaTe2 samples. The photoluminescence spectra of “heavily doped” semiconductors are usually characterized by the broadening of the photoluminescence bands that is caused by the fluctuations of the forbidden band edges. The deep photoluminescence region observed (0.8–1.3 eV) consists of two peaks. One of them is located at 0.955 eV and has been reported before. Another, totally new band was discovered at 1.14 eV. The low‐temperature j‐shift of both bands was detected. Also, rather significant blue shift with the increasing temperature was noticed. It is proposed that both bands consist of two recombination channels. At low temperatures tail‐to‐impurity recombination dominates. As the temperature increases, the tail‐to‐impurity recombination transforms into band‐to‐impurity recombination. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Sapphire‐etched vertical‐electrode nitride‐based semiconductor light‐emitting diode (SEVENS LED) fabricated by the wet etching technique
Authors: Kim Seong‐Jin 
Published: March 2006

AbstractA sapphire‐etched vertical‐electrode nitride‐based semiconductor (SEVENS) light‐emitting diode (LED) has been fabricated by a selective wet etching technique. The light output power of the SEVENS LED is substantially enhanced compared with a conventional NiAu lateral‐electrode (LE) GaN‐based LED formed on a sapphire substrate. The light output power of the SEVENS LED is not saturated up to as high as 300 mA junction current, being a notable improvement over that (250 mA junction current) of the LE LED. The 250 mA light output power of the SEVENS LED with an entire sapphire‐removed surface is 4.3 times larger than that of the LE LED. The variations of peak wavelength and full width at half maximum are less for the SEVENS LED compared to the LE LED. This performance improvement is attributed to the transfer of the sapphire substrate to a silicon substrate and the microroughened surface self‐formed by wet etching of the sapphire substrate. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fabrication of III–V nano‐ and microtubes using MOVPE grown materials
Authors: Paetzelt H. , Gottschalch V. , Bauer J. , Herrnberger H. , Wagner G. 
Published: March 2006

AbstractIn this issue's Editor's Choice [1], Paetzelt et al. present a novel class of nano‐ and micro‐dimensional sized objects formed by releasing thin strained multi‐layers from their substrate by selective etching of a sacrificial layer after growth by metal‐organic vapor‐phase epitaxy (MOVPE).The cover picture is an SEM image of a multi‐layer tube rolled in 〈110〉 direction with a diameter of around 6 µm. This tube was fabricated from the layer system: GaAs buffer/AlAs sacrificial layer/In0.37Ga0.63As strained layer/Al0.35Ga0.65As bottom barrier/GaAs quantum well and Al0.35Ga0.65As top barrier.The first author, Hendrik Paetzelt, is current a Ph.D. student at the Institute of Inorganic Chemistry of the University of Leipzig. He investigates the growth of highly strained thin films and selective wetchemical etching techniques for the fabrication and the subsequent characterization of nano‐ and microtubes from multi‐layer systems. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of magnetic field on off‐axis donor binding energy in a nanotube
Authors: Orozco E. A. , Gonzalez J. D. , Duarte O. S. , Mikhailov I. D. 
Published: March 2006

AbstractWe analyze the effect of the mixing of the low‐lying s and px ,y subbands on the ground‐state binding energy of the off‐axis donors in cylindrical nanotubes in the presence of a magnetic field parallel to the axis. We express the wave function as a product of combinations of s and p subband wave functions and an envelope function that depends only on the electron–ion separation. By using the variational principle we derive a differential equation for the envelope function, which we solve numerically. The curves for the dependence of the ground‐state binding energies on the donor distance from the axis are presented and it is shown that the effect of the subband mixing for off‐axis donors in nanotubes is considerable. It is found that the magnetic field enhances the binding energies of donors located close to the axis whereas for donors located far from the axis the effect of the magnetic field on the binding energy is the opposite. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Study of the electronic structures of sheelite and sheelite‐like PbWO4
Authors: Yi Zhijun , Liu Tingyu , Zhang Qiren , Sun Yuanyuan 
Published: March 2006

AbstractThe electronic structures of different types of PbWO4 (PWO) crystal have been studied within the framework of the fully relativistic self‐consistent Dirac–Slater theory, using a numerically discrete variational (DV‐Xα) method. In the calculation, the lattice relaxation of sheelite‐like PWO (Pb7.5W8O32) is considered. The densities of states and joint densities of states for sheelite and sheelite‐like PWO clusters are obtained. The calculated results indicate that the electronic structures of sheelite and sheelite‐like PWO clusters embedded in themselves are very similar. However, when the sheelite and sheelite‐like PWO clusters are embedded in each other the electronic structures change significantly; for example, peaks for density of states become undistinguishable, and some states even become forbidden. The calculated results show that stolzite‐type PWO may be the most stable structure and the physical properties of the PWO crystal are sensitive to its structure. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Investigations of the optical and EPR spectra of V3+ ions in C(NH2)3Al(SO4)2 · 6H2O crystal
Authors: Feng Wen‐Lin , Wu Xiao‐Xuan , Zheng Wen‐Chen 
Published: March 2006

AbstractBy means of the diagonalization of the complete energy matrix of 3d2/d8 ions in trigonal symmetry and in consideration of the covalency reduction effect, the optical and EPR spectra of V3+ ions in C(NH2)3Al(SO4)2 · 6H2O crystal are calculated. The results are in agreement with the observed values. The difficulty about the too‐large spin–orbit coupling parameter in the explanation of EPR parameters from the Abragam and Pryce model is removed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electronic properties of ThSiO4 polymorphs (thorite and huttonite) from first principles calculations
Authors: Shein I. R. , Shein K. I. , Medvedeva N. I. , Ivanovskii A. L. 
Published: March 2006

AbstractThe full‐potential linearized augmented plane wave method with the generalized gradient approximation for the exchange and correlation potential (FLAPW‐GGA) is used to understand the electronic properties of the tetragonal (thorite) and monoclinic (huttonite) polymorphs of thorium orthosilicate ThSiO4. Electronic bands, total and partial density of states and charge density were obtained for the first time and applied to describe the chemical bonding. Both ThSiO4 phases are insulating; the Th 5f states are itinerant and overlap with O 2p bands, the chemical bonding in the both phases is a combination of covalent and ionic types. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Note on the calculation of analytical Hessians in the zeroth‐order regular approximation (ZORA)
Authors: van Lenthe J. H. , van Lingen J. N. J. 
Published: March 2006

AbstractThe previously proposed atomic zeroth‐order regular approximation (ZORA) approach, which was shown to eliminate the gauge dependent effect on gradients and to be remarkably accurate for geometry optimizations, is tested for the calculation of analytical second derivatives. It is shown that the resulting analytic second derivatives are indeed exact within this approximation. The method proves to yield frequencies that are remarkably close to the experimental frequency for uranium hexafluoride but less satisfactory for the gold dimer. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
A conversation with Dr David Reilly
Authors: Reilly David 
Published: March 2006

AbstractDavid Reilly, FRCP, MRCGP, FFHom, is a doctor, active in caring for people. He is a Consultant Physician at the Centre for Integrative Care, Glasgow Homoeopathic Hospital; Honorary Senior Lecturer at Glasgow University; Visiting Professor of Medicine in Maryland and faculty member at Harvard Medical School, USA. Trained in orthodox medicine (as a physician and as a GP), complementary medicine (mainly homoeopathy and acupuncture) and mind–body medicine, he has sought fresh ways of approaching medicine and human caring, emphasizing the innate healing capacity in people, the factors that modify this, and their interaction with therapeutic process –especially in the therapeutic encounter. His ideas were recently used as core elements in the Fifth Wave document on future public health development (www.scottishcouncilfoundation.org). A published scientist, a teacher and a broadcaster, he is also a musician and poet and explores the synthesis of art and science (which he nicknamed ‘artience’). He is currently Scotland's Dynamic Place Award ‘Person of the Year’ –for achieving a new standard in healing environment created at Glasgow Homoeopathic Hospital (www.ghh.info). At a personal level he says, ‘I am now old enough to have made major mistakes and young enough to learn from them. Fortunately, I am not as old as I used to be.’ Copyright © 2004 Whurr Publishers Ltd.
Narratives of hope: Keisha's story
Authors: Turner de Sales 
Published: March 2006

AbstractIn this paper, a case study exemplar is discussed to illustrate how the phenomenon of hope was explicated for one Australian youth. A total of 10 youths between the ages of 15 and 24 participated in this study. Data were collected using photographs taken by the participants and in‐depth interviews. Gadamerian hermeneutic phenomenology was used to conduct this study and, to become immersed in the data, the researcher devised a unique method of analysis consistent with the study's philosophical underpinnings. The findings illuminate the phenomenon of hope, attesting to its importance to the study participants. Copyright © 2004 Whurr Publishers Ltd.