bluuebunny/crossref_metadata_2025 huggingface dataset:
Apatite‐coated poly(lactic‐co‐glycolic acid) microspheres as an injectable scaffold for bone tissue engineering
Authors: Kang Sun‐Woong , Yang Hee Seok , Seo Sang‐Woo , Han Dong Keun , Kim Byung‐Soo
Published: September 2007

Biodegradable polymer/ceramic composite scaffold could overcome limitations of biodegradable polymers or ceramics for bone regeneration. Injectable scaffold has raised great interest for bone regeneration in vivo, since it allows one for easy filling of irregularly shaped bone defects and implantation of osteogenic cells through minimally invasive surgical procedures The purpose of this study was to determine whether apatite‐coated poly(lactic‐co‐glycolic acid) (PLGA) microspheres could be used as an injectable scaffold to regenerate bone in vivo. Apatite‐coated PLGA microspheres were fabricated by incubating PLGA microspheres in simulated body fluid. The apatite that coated the PLGA microsphere surfaces was similar to apatite in natural bone, as demonstrated by scanning electron microscopy, X‐ray diffraction spectra, energy‐dispersive spectroscopy, and Fourier transformed‐infrared spectroscopy analyses. Rat osteoblasts were mixed with apatite‐coated PLGA microspheres and injected immediately into subcutaneous sites of athymic mice. Osteoblast transplantation with plain PLGA microspheres served as a control. Histological analysis of the implants at 6 weeks with hematoxylin and eosin staining, Masson's trichrome staining, and von Kossa staining revealed much better regeneration of bone in the apatite‐coated PLGA microsphere group than the plain PLGA microsphere group. The new bone formation area and the calcium content of the implants were significantly higher in the apatite‐coated PLGA microsphere group than in the plain PLGA microsphere group. This study demonstrates the feasibility of using apatite‐coated PLGA microspheres as an injectable scaffold for in vivo bone tissue engineering. This scaffold may be useful for bone regeneration through minimally invasive surgical procedures in orthopedic applications. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Fibrous capsule formation around titanium and copper
Authors: Suska Felicia , Emanuelsson Lena , Johansson Anna , Tengvall Pentti , Thomsen Peter
Published: September 2007

Previous studies suggest that implant material properties influence the quality and quantity of fibrous capsule around the implant. However, the precise relation between material surface chemistry, early inflammatory response, and fibrous subsequent repair outcome is still unknown. Titanium (Ti) and copper (Cu), surfaces with different inflammatory potential, were implanted subcutaneously in rats and retrieved fibrous capsules were analyzed after 28 and 56 days. Histological examinations show pronounced differences in capsule morphology. The fibrous capsule around Ti was thinner than that around Cu, with less number of the inflammatory cells in the layer close to the implant surface, and less and smaller blood vessels. The capsule around Cu was thick, with a large number of the inflammatory cells, particularly macrophages and giant cells, and increased number of blood vessels. Our study suggests that material surface properties, which initiate early, multiple cellular inflammatory events, are also associated with increased fibrosis and angiogenesis during repair phase. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Non‐conventional signal transduction by type 1 interferons: The NF‐κB pathway
Authors: Du Ziyun , Wei Lai , Murti Aruna , Pfeffer Susan R. , Fan Meiyun , Yang Chuan He , Pfeffer Lawrence M.
Published: October 2007

Type I interferons (IFNs) regulate diverse cellular functions by modulating the expression of IFN‐stimulated genes (ISGs) through the activation of the well established signal transduction pathway of the Janus Kinase (JAK) and signal transducers and activators of transcription (STAT) proteins. Although the JAK–STAT signal transduction pathway is critical in mediating IFN's antiviral and antiproliferative activities, other signaling pathways are activated by IFNs and regulate cellular response to IFN. The NF‐κB transcription factor regulates the expression of genes involved in cell survival and immune responses. We have identified a novel IFN mediated signal pathway that leads to NF‐κB activation and demonstrate that a subset of ISGs that play key roles in cellular response to IFN is regulated by NF‐κB. This review focuses on the IFN‐induced NF‐κB activation pathway and the role of NF‐κB in ISG expression, antiviral activity and apoptosis, and the therapeutic application of IFN in cancer and infectious disease. J. Cell. Biochem. 102: 1087–1094, 2007. © 2007 Wiley‐Liss, Inc.
Generation of novel, secreted epidermal growth factor receptor (EGFR/ErbB1) isoforms via metalloprotease‐dependent ectodomain shedding and exosome secretion
Authors: Sanderson Michael P. , Keller Sascha , Alonso Angel , Riedle Svenja , Dempsey Peter J. , Altevogt Peter
Published: October 2007

Exosomes are small membrane vesicles derived from intracellular multivescicular bodies (MVBs) that can undergo constitutive and regulated secretion from cells. Exosomes can also secrete soluble proteins through metalloprotease‐dependent ectodomain shedding. In this study, we sought to determine whether ErbB1 receptors are present within exosomes isolated from the human keratinocyte cell line, HaCaT, and whether exosome‐associated ErbB1 receptors can undergo further proteolytic processing. We show that full‐length transmembrane ErbB1 is secreted in HaCaT exosomes. EGF treatment and calcium flux stimulated the release of phosphorylated ErbB1 in exosomes but only ligand‐stimulated release was blocked by the ErbB1 kinase inhibitor, AG1478, indicating that ligand‐dependent ErbB1 receptor activation can initiate ErbB1 secretion into exosomes. In addition, other immunoreactive but truncated ErbB1 isoforms were detected in exosomes suggestive of additional proteolytic processing. We demonstrate that cellular and exosomal ErbB1 receptors can undergo ectodomain shedding to generate soluble N‐terminal ectodomains and membrane‐associated C‐terminal remnant fragments (CTFs). ErbB1 shedding was activated by calcium flux and the metalloprotease activator APMA (4‐aminophenylmercuric acetate) and was blocked by a metalloprotease inhibitor (GM6001). Soluble ErbB1 ectodomains shed into conditioned medium retained the ability to bind exogenous ligand. Our results provide new insights into the proteolysis, trafficking and fate of ErbB1 receptors and suggest that the novel ErbB1 isoforms may have functions distinct from the plasma membrane receptor. J. Cell. Biochem. 103: 1783–1797, 2007. © 2007 Wiley‐Liss, Inc.
Trifluoromethanesulfonic acid, an alternative solvent medium for the direct electrophilic fluorination of DOPA: new syntheses of 6‐[18F]fluoro‐L‐DOPA and 6‐[18F]fluoro‐D‐DOPA
Authors: Behnam Azad Babak , Chirakal Raman , Schrobilgen Gary J.
Published: October 2007

Previous work from this laboratory has shown that the direct fluorination of 3, 4‐dihydroxy‐phenyl‐L‐alanine (L‐DOPA) in anhydrous HF (aHF) or BF3/HF with F2 is an efficient method for the synthesis of 6‐fluoro‐L‐DOPA. Since then, 18F‐labeled 6‐fluoro‐L‐DOPA ([18F]6‐fluoro‐L‐DOPA) has been used to study presynaptic dopaminergic function in the human brain and to monitor gastrointestinal carcinoid tumors.

This work demonstrates that the reactivity and selectivity of F2 toward L‐DOPA in CF3SO3H is comparable with that in aHF. This new synthetic procedure has led to the production of [18F]fluoro‐L‐DOPA and [18F]fluoro‐D‐DOPA isomers in 17±2% radiochemical yields (decay corrected with respect to [18F]F2). The 2‐ and 6‐FDOPA isomers were separated by HPLC and subsequently characterized by 19F NMR spectroscopy. The corresponding [18F]‐FDOPA enantiomers have been obtained in clinically useful quantities by a synthetic approach that avoids the use of aHF. Copyright © 2007 John Wiley & Sons, Ltd.
A compact one‐dimensional modal FDTD method
Authors: Luo Shuiping , Chen Zhizhang (David)
Published: September 2007

The finite‐difference time‐domain (FDTD) method is an effective technique for computing wideband electrical parameters such as scattering parameters of waveguide structures. in the computations, a known incident is normally required and is usually obtained with a simulation of a long uniform structure. For a three‐dimensional problem, simulation of a long structure can be very memory‐ and CPU time‐intensive. In addition, effective absorbing boundary conditions are needed to effectively terminate the structure even at and below the cutoff frequencies. To address these issues, many one‐dimensional FDTD methods and absorbing schemes were proposed. However, they all have dispersion characteristics different from those of the conventional FDTD method, leading to undesired errors or reflections. In this paper, a new one‐dimensional scheme is developed that has numerical dispersion characteristics very similar to that of the conventional FDTD method. When used as the absorbing boundary condition, it generates reflections of less than −200 dB even at and below the cutoff frequencies for the considered modes. When used to obtain the incident wave, its results have difference of less than −200 dB from that produced by the conventional FDTD method. Copyright © 2007 John Wiley & Sons, Ltd.
Raman scattering from double‐walled carbon nanotubes
Authors: Kuzmany H. , Plank W. , Pfeiffer R. , Simon F.
Published: September 2007

Raman scattering from double‐walled carbon nanotubes is reported with particular emphasis on the response from the radial breathing mode (RBM) of the inner‐shell tubes. The unexpected large number of very narrow lines observed is explained by the growth of one and the same inner tube type in different outer tubes in a highly shielded environment. The response of the RBM and of the G‐line is used to analyze the transition from peapods to double‐walled carbon nanotubes. During the transformation process the Raman response disappears for a short time, indicating the existence of some Raman dark matter. By preparing the starting peapods from heterofullerenes such as (C59N)2 or 13C‐substituted fullerenes, hetero‐nanotubes can be grown where nitrogen or the 13C atoms are incorporated into the inner tube wall. Copyright © 2007 John Wiley & Sons, Ltd.
Vibrational spectroscopy of the seselin crystal
Authors: Bento R. R. F. , Freire P. T. C. , Lemos V. , Teixeira A. M. R. , Lima R. J. C. , de Oliveira M. C. F. , Mafezoli J. , Mourão G. M. M. S. , Pontes F. M.
Published: September 2007

Seselin, C14H12O3, is a coumarin which crystallizes in a monoclinic structure P21/b(C2h5) with four molecules per unit cell. In a Fourier‐transform Raman spectroscopic study performed at room temperature, several normal modes were observed. Vibrational wavenumber and wave vector calculations using density functional theory were compared with experiment, which allowed the assignment of a number of normal modes of the crystal. Temperature‐dependent Raman spectra were recorded between 10 and 300 K. No anomalies were observed in the phonon spectra, indicating that the monoclinic structure remains stable. Copyright © 2007 John Wiley & Sons, Ltd.
Raman spectroscopy of smithsonite
Authors: Frost Ray L. , Hales Matt C. , Wain Daria L.
Published: September 2007

Raman spectroscopy at both 298 and 77 K has been used to study a series of selected natural smithsonites from different origins. An intense sharp band at 1092 cm−1 is assigned to the CO32− symmetric stretching vibration. Impurities of hydrozincite are identified by a band around 1060 cm−1. An additional band at 1088 cm−1 which is observed in the 298 K spectra but not in the 77 K spectra is attributed to a CO32− hot band. Raman spectra of smithsonite show a single band in the 1405–1409 cm−1 range assigned to the ν3 (CO3)2− antisymmetric stretching mode. The observation of additional bands for the ν3g modes for some smithsonites is significant in that it shows distortion of the ZnO6 octahedron. No ν2 bending modes are observed for smithsonite. A single band at 730 cm−1 is assigned to the ν4 in phase bending mode. Multiple bands be attributed to the structural distortion are observed for the carbonate ν4 in phase bending modes in the Raman spectrum of hydrozincite with bands at 733, 707 and 636 cm−1. An intense band at 304 cm−1 is attributed to the ZnO symmetric stretching vibration. Copyright © 2007 John Wiley & Sons, Ltd.
Effect of pre‐harvest salicylic acid spray treatment on post‐harvest antioxidant in the pulp and peel of ‘Cara cara’ navel orange (Citrus sinenisis L. Osbeck)
Authors: Huang Renhua , Xia Renxue , Lu Yunmei , Hu Liming , Xu Yongjie
Published: October 2007

BACKGROUND: Exogenous salicylic acid (SA) pretreatment could change the antioxidant system and maintain the nutritional value of fruits and vegetables, which have a higher ability to withstand oxidation injuries. However, the relationship between a pre‐harvest SA spray and post‐harvest antioxidant compounds in fruit remains unknown.

RESULTS: The post‐harvest behaviour of antioxidant compounds in ‘Cara cara’ navel orange (Citrus sinenisis L. Osbeck) fruit was investigated in relation to the pre‐harvest SA applications. Pre‐harvest SA treatment significantly increased the content of carotenoids (lycopene and α‐carotene), ascorbic acid, glutathione, total phenolics, and total flavonoids in the pulp and peel during storage. Furthermore, the values of these antioxidant compounds were high in the fruit treated with high SA concentrations (1.0 and 2.0 mmol L−1). High antioxidant activity was also observed in the SA pre‐harvest treated fruit when compared with the control. The positive relationships were found between the antioxidant activity and the content of these active compounds.

CONCLUSION: These results indicated that SA could maintain fruit antioxidant activity and nutrition which was shown by the increase in content of antioxidant compounds and suggested that pre‐harvest treatment with SA promised a novel technology, which was a substitute for the perplexing programme control of post‐harvest nutrition in fruit. Copyright © 2007 Society of Chemical Industry
Enzymatic modification as a tool to improve the functional properties of heat‐processed soy flour
Authors: Radha Cheruppanpullil , Ramesh Kumar Parigi , Prakash Vishweshwaraiah
Published: October 2007

BACKGROUND: There are a number of antinutritional factors present in soybeans that exert a negative impact on the nutritional quality of the protein. Among those factors that are destroyed by heat treatment are protease inhibitors and lectins. Protease inhibitors show antinutritional effect and moreover the digestibility of the protein is limited by the presence of these antinutrients. The aims of the present study are (1) to study the effect of autoclaving on the trypsin inhibitor inactivation, nitrogen solubility and protein digestibility of defatted soy flour and (2) to study the effect of enzymatic modification on the functional properties of autoclaved soy flour.

RESULTS: The solubility of the soy flour decreased with increase in autoclaving time. Partial hydrolysis of the autoclaved soy flour increased its acid solubility (pH 4.5) from 17% to 56% over a control value of 24% without affecting its functional properties. Inactivation of trypsin inhibitors improved the protein digestibility of soy flour from 25% to 95%. Particle size analysis of the autoclaved flour indicated the formation of soy protein aggregates, which resulted in poor solubility. The enzymatic modification of autoclaved soy flour resulted in its property as a good emulsifying agent with an emulsion capacity of 118 ± 4 mL.

CONCLUSION: Enzymatic modification of the heat‐processed soy flour increased its solubility and other functional attributes. The increased acid solubility would be advantageous in the utilization of soy proteins in acidic foods. Thus the autoclaved and partially modified soy flour is a potential source for specific functional foods. Copyright © 2007 Society of Chemical Industry
The universal covering homomorphism in o‐minimal expansions of groups
Authors: Edmundo Mário J. , Eleftheriou Pantelis E.
Published: September 2007

Suppose G is a definably connected, definable group in an o‐minimal expansion of an ordered group. We show that the o‐minimal universal covering homomorphism $ \tilde p $: $ \tilde G $→ G is a locally definable covering homomorphism and π1(G) is isomorphic to the o‐minimal fundamental group π (G) of G defined using locally definable covering homomorphisms. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A ratio‐dependent predator–prey model with stage structure and optimal harvesting policy
Authors: Cai Liming , Li Xuezhi , Yu Jingyuan , Zhu Guangtian
Published: October 2007

In this paper, a ratio‐dependent predator–prey model with stage structure and harvesting is investigated. Mathematical analyses of the model equations with regard to boundedness of solutions, nature of equilibria, permanence and stability are performed. By constructing appropriate Lyapunov functions, a set of easily verifiable sufficient conditions are obtained for the global asymptotic stability of nonnegative equilibria of the model. The existence possibilities of bioeconomic equilibria have been examined. An optimal harvesting policy is also given by using Pontryagin's maximal principle. Copyright © 2007 John Wiley & Sons, Ltd.
Enhanced relative BOLD signal changes in T2‐weighted stimulated echoes
Authors: Goerke Ute , van de Moortele Pierre‐Francois , Ugurbil Kamil
Published: September 2007

The origin of the stimulus/task‐induced signal changes in spin echo (SE) functional MRI (fMRI) at high magnetic fields is dynamic averaging due to diffusion in the presence of field gradients surrounding deoxyhemoglobin‐containing microvasculature. The same mechanism is expected to be operative in stimulated echoes (STE). Compared to SE‐fMRI, however, STE‐fMRI has the potential for larger diffusion weighting and consequently larger stimulus/task‐induced signal changes as a result of an additional delay, the mixing time, TM. In the present study, functional signal changes were quantified for both primary echo (PRE) and STE as a function of echo and mixing time. The relative blood oxygenation level dependent (BOLD) signal changes in STE were larger than in PRE at the same echo time and increased with both mixing and echo time. The contrast‐to‐noise ratio (CNR) of the STE, however, is close to the CNR of the PRE, indicating an increase of physiological noise with longer mixing times. In addition, the signal attenuation due to diffusion in the presence of magnetic field gradients near blood vessels was modeled using Monte Carlo simulations. They support the hypothesis that the sensitivity of the STE to fluctuations of susceptibility‐induced magnetic field gradients near microvasculature is enhanced as a result of an extended diffusion time. Magn Reson Med 58:754–762, 2007. © 2007 Wiley‐Liss, Inc.
A method for improving the performance of gradient systems for diffusion‐weighted MRI
Authors: Nagy Zoltan , Weiskopf Nikolaus , Alexander Daniel C. , Deichmann Ralf
Published: September 2007

The MR signal is sensitive to diffusion. This effect can be increased by the use of large, balanced bipolar gradients. The gradient systems of MR scanners are calibrated at installation and during regular servicing visits. Because the measured apparent diffusion constant (ADC) depends on the square of the amplitude of the diffusion sensitizing gradients, errors in the gradient calibration are exaggerated. If the error is varying among the different gradient axes, it will affect the estimated degree of anisotropy. To assess the gradient calibration accuracy in a whole‐body MRI scanner, ADC values were calculated for a uniform water phantom along each gradient direction while monitoring the temperature. Knowledge of the temperature allows the expected diffusion constant of water to be calculated independent of the MRI measurement. It was found that the gradient axes (±x, ±y, ±z) were calibrated differently, resulting in offset ADC values. A method is presented to rescale the amplitude of each of the six principal gradient axes within the MR pulse sequence. The scaling factor is the square root of the ratio of the expected and observed diffusion constants. In addition, fiber tracking results in the human brain were noticeably affected by improving the gradient system calibration. Magn Reson Med 58:763–768, 2007. © 2007 Wiley‐Liss, Inc.
Very‐low‐frequency electron paramagnetic resonance (EPR) imaging of nitroxide‐loaded cells
Authors: Kao Joseph P.Y. , Barth Eugene D. , Burks Scott R. , Smithback Philip , Mailer Colin , Ahn Kang‐Hyun , Halpern Howard J. , Rosen Gerald M.
Published: September 2007

Recent advances in electron paramagnetic resonance (EPR) imaging have made it possible to image, in real time in vivo, cells that have been labeled with nitroxide spin probes. We previously reported that cells can be loaded to high (millimolar) intracellular concentrations with (2,2,5,5‐tetramethylpyrrolidin‐1‐oxyl‐3‐ylmethyl)amine‐N,N‐diacetic acid by incubation with the corresponding acetoxymethyl (AM) ester. Furthermore, the intracellular lifetime (t1/e) of this nitroxide is 114 min—sufficiently long to permit in vivo imaging studies. In the present study, at a gradient of ∼50 mT/m, we acquire and compare EPR images of a three‐tube phantom, filled with either a 200‐μM solution of the nitroxide, or a suspension of cells preincubated with the nitroxide AM ester. In both cases, 3‐mm resolution images can be acquired with excellent signal‐to‐noise ratios (SNRs). These findings indicate that cells well‐loaded with nitroxide are readily imageable by EPR imaging, and that in vivo tracking studies utilizing such cells should be feasible. Magn Reson Med 58:850–854, 2007. © 2007 Wiley‐Liss, Inc.
Combined functional and viability cardiac MR imaging in a single breathhold
Authors: Ibrahim El‐Sayed H. , Stuber Matthias , Kraitchman Dara L. , Weiss Robert G. , Osman Nael F.
Published: September 2007

The combination of cardiac viability and functional information enhances the identification of different heart tissues in the setting of ischemic heart disease. A method has recently been proposed for obtaining black‐blood delayed‐enhancement (DE) viability images using the stimulated‐echo acquisition mode (STEAM) MRI pulse sequence in a single short breathhold. The method was validated against conventional inversion‐recovery (IR) DE images for identifying regions of myocardial infarction (MI). The method was based on the acquisition of three consecutive images of the same anatomical slice. One image has T1‐weighted contrast in which infarction appears bright. The two other images are used to construct an anatomical image of the heart, which is combined with the first image to produce a black‐blood viability image. However, using appropriate modulation and demodulation frequencies, the latter two images bear useful information about myocardial deformation that results in a cardiac strain‐encoding (SENC) functional image. In this work, a method is proposed for obtaining three consecutive SENC images in a single acquisition that can be combined to produce a composite image of the heart, which shows both functional and viability information. The proposed technique reduces scan time by one‐half, compared with separate acquisitions of functional and viability images, and alleviates misregistration problems caused by separate breathholds. Magn Reson Med 58:843–849, 2007. © 2007 Wiley‐Liss, Inc.
Modelling Staphylococcus aureus–induced septicemia using NMR
Authors: Plummer R. , Bodkin J. , Yau T.W. , Power D. , Pantarat N. , Larkin T.J. , Szekely D. , Bubb W.A. , Sorrell T.C. , Kuchel P.W.
Published: September 2007

We present a novel NMR‐based study of the molecular aspects of the “attack” on human red blood cells (RBCs) by growing bacteria. Staphylococcus aureus expresses virulence factors, including α‐hemolysin, which contribute to the clinical condition known as septic shock. α‐Hemolysin is a pore‐forming toxin and its secretion increases the permeability of a range of mammalian cell types infected with S. aureus. 31P NMR spectra of the probe molecules dimethyl methylphosphonate (DMMP) and hypophosphite (HPA) in RBC suspensions show separate intra‐ and extracellular resonances. These resonances coalesced over time in RBC suspensions inoculated with S. aureus or pure α‐hemolysin, due to increasing permeability of the RBC membrane. Increased RBC permeability resulted in leakage of intracellular proteins, plus an increase in the exchange rate of the solutes between the intra‐ and extracellular compartments, both effects contributing to the coalescence of the split peaks. The addition of antibiotics prevented peak coalescence and enabled the minimal inhibitory concentration (MIC) for eight strains of S. aureus to be determined for oxacillin and erythromycin. The MIC values obtained by using 31P NMR spectroscopy were within one dilution of the MICs obtained using the standard National Committee for Clinical Laboratory Standards (NCCLS) method. The results are encouraging for the use of NMR spectroscopy in clinical microbiology. Magn Reson Med 58:656–665, 2007. © 2007 Wiley‐Liss, Inc.
Parallel load‐balanced simulation for short‐range interaction particle methods with hierarchical particle grouping based on orthogonal recursive bisection
Authors: Fleissner Florian , Eberhard Peter
Published: September 2007

We describe an efficient load‐balancing algorithm for parallel simulations of particle‐based discretization methods such as the discrete element method or smoothed particle hydrodynamics. Our approach is based on an orthogonal recursive bisection of the simulation domain that is the basis for recursive particle grouping and assignment of particle groups to the parallel processors. Particle grouping is carried out based on sampled discrete particle distribution functions. For interaction detection and computation, which is the core part of particle simulations, we employ a hierarchical pruning algorithm for an efficient exclusion of non‐interacting particles via the detection of non‐overlapping bounding boxes. Load balancing is based on a hierarchical PI‐controller approach, where the differences of processor per time step waiting times serve as controller input. Copyright © 2007 John Wiley & Sons, Ltd.
Street lamps, alleys, ratio analysis, and nonprofit organizations
Authors: Tinkelman Daniel , Donabedian Bairj
Published: September 2007

This article offers an accounting‐based framework for evaluating the efficiency of nonprofit organizations using four factors. Separately, these factors reflect (1) the proportion of revenues actually used in the current year, (2) the proportion of the expenditures allocated to programs, (3) the units of output produced from that spending, and (4) the value of the units produced, expressed in terms of an index value. Combined, these four factors measure the value of units produced per dollar of revenue received, an accounting measure of overall efficiency. Using this framework provides insight into both the appropriateness and the limitations of employing solely financial measures to judge nonprofit organizations and also identifies conceptual areas absent from currently available evaluation tools.
Nonprofit association CEOs how their context shapes what, how, and why they learn
Authors: Sherlock John J. , Nathan Maria L.
Published: September 2007

This qualitative study explored the learning experiences of twelve national nonprofit membership association CEOs using a phenomenological research design. While the professional context of an organization's chief executive is considered unique from other executive positions, the impact of this context on what and how CEOs learned was unclear. The findings describe association CEO learning as being affected in significant ways by the politically charged context in which the nonprofit association CEO operates with his or her board of directors. Power imbalances with staff and the board make learning through traditional organizational dialogue a less useful learning process for the CEOs. Furthermore, the feelings of isolation and vulnerability that are generated from the nonprofit association CEO context often cause CEOs to use private reflection and dialogue with their spouse as primary learning mechanisms. The study concludes that the association CEO context uniquely and profoundly shapes what, how, and why CEOs learn. Perhaps lacking the financial security of lucrative severance payments, which are often specified in employment contracts of for‐profit CEOs, the nonprofit association CEO will often temper his or her actions to avoid personal vulnerability with a politically charged board of directors.
Dr. Carver's odyssey
Authors: Murray Vic
Published: September 2007

Boards That Make a Difference: A New Design for Leadership in Nonprofit and Public Organizations (Third Edition), by John Carver. San Francisco: Jossey‐Bass, 2006. 448 pp., $36.00 cloth.
A possible case of renal osteodystrophy in a skeleton from medieval Wharram Percy, England
Authors: Mays S. , Turner‐Walker G.
Published: October 2007

The skeletal remains of a child aged 13–15 years, recovered from Wharram Percy, England, and dating from AD 960–1700, were examined using gross observation, radiography and scanning electron microscopy. Lesions suggestive of renal osteodystrophy were found. Palaeopathological recognition of renal disease has hitherto relied upon the identification of soft tissue lesions or the presence of urinary calculi. This appears to be the first palaeopathological identification of renal insufficiency on the basis of skeletal changes alone. Copyright © 2007 John Wiley & Sons, Ltd.
Studies on the glutathione S‐transferase proteome of adult Drosophila melanogaster: Responsiveness to chemical challenge
Authors: Alias Zazali , Clark Alan G.
Published: October 2007

GSTs from adult Drosophila melanogaster have been partially purified using three different affinity chromatography media and separated by 2‐DE. Nine GSTs have been identified by MALDI‐TOF MS. In the absence of special treatments, eight GSTs could be positively identified. These were DmGSTs D1 (the dominant Delta isoform which was present in five protein zones of differing pI) and D3 (and possibly also D5); the Epsilon‐class GSTs E3, 6, 7 and 9 and a previously uncharacterised, probable member of the class, CG16936. The Sigma‐class DmGSTS1 was prominent. DmGSTD2 was detected only after pretreatment of the flies with Phenobarbital (PhB). Treatment with Paraquat (PQ) led to an increase in the total GST activity, as measured with the substrates 1‐chloro‐2,4‐dinitrobenzene (CDNB) and 3,4‐dichloro‐nitrobenzene (DCNB) and an increase in the relative amounts of the D1, D3, E6 and E7 isoforms. PhB treatment led to increases in the relative amounts of the D1, D2, E3, E6, E7 and E9 isoforms detected with a possible depression in the relative amount of GSTS1. CG16936 was unaffected by either pretreatment.
Light‐induced immobilisation of biomolecules as an attractive alternative to microdroplet dispensing‐based arraying technologies
Authors: Duroux Meg , Skovsen Esben , Neves‐Petersen Maria Teresa , Duroux Laurent , Gurevich Leonid , Petersen Steffen B.
Published: October 2007

The present work shows how UV ‘light‐induced molecular immobilisation’ (LIMI) of biomolecules onto thiol reactive surfaces can be used to make biosensors, without the need for traditional microdispensing technologies. Using ‘LIMI,’ arrays of biomolecules can be created with a high degree of reproducibility. This technology can be used to circumvent the need for often expensive nano/microdispensing technologies. The ultimate size of the immobilised spots is defined by the focal area of the UV beam, which for a diffraction‐limited beam can be less than 1 μm in diameter. LIMI has the added benefit that the immobilised molecules will be spatially oriented and covalently bound to the surface. The activity of the sensor molecules is retained. Antibody sensor arrays made using LIMI demonstrated successful antigen binding. In addition, the pattern of immobilised molecules on the surface is not restricted to conventional array formats. The ultimate consequence of the LIMI is that it is possible to write complex protein patterns using bitmaps at high resolution onto substrates. Thus, LIMI of biomolecules provides a new technological platform for biomolecular immobilisation and the potential for replacing present microdispensing arraying technologies.
1,1,1‐Trichloro‐3‐(1‐phenethylamino‐ethylidene)‐ pentane‐2,4‐dione—synthesis, spectroscopic, theoretical and structural elucidation
Authors: Kolev Tsonko M. , Angelov Plamen
Published: September 2007

1,1,1‐Trichloro‐3‐(1‐phenethylamino‐ethylidene)‐pentane‐2,4‐dione is spectroscopically and structurally elucidated by means of linear‐polarized IR spectroscopy (IR‐LD) of oriented solids as a colloidal suspension in nematic liquid crystal. Structural information and IR‐spectroscopic assignment are supported by quantum chemical calculations at MP2 and B3LYP level of theory and 6‐311++G** basis set. The geometry is characterized with an inramolecular hydrogen bond of NH…OC with length of 2.526 Å and a NHO angle of 140.5(1)°. The NHC(CH3)CCCO(CH3) fragment is nearly flat with a maximal deviation of total planarity of 10.4°. Copyright © 2007 John Wiley & Sons, Ltd.
Highly efficient and well‐controlled ambient temperature RAFT polymerization of glycidyl methacrylate under visible light radiation
Authors: Yin Huiwen , Zheng Haimei , Lu Lican , Liu Pengsheng , Cai Yuanli
Published: October 2007

A range of well‐defined poly(glycidyl methacrylate) (PGMA) polymers and their corresponding block copolymers were synthesized via 2‐cyanoprop‐2‐yl(4‐fluoro) dithiobenzoate or CPFDB‐mediated ambient temperature reversible addition fragmentation chain transfer radical polymerization or RAFT polymerization under environmentally friendly visible light radiation (λ = 405–577 nm), using a (2,4,6‐trimethylbenzoyl) diphenylphosphine oxide photoinitiator. As comparison, CPFDB‐mediated ambient temperature RAFT polymerizations of glycidyl methacrylate (GMA) under both full‐wave radiation (λ = 254–577 nm) and long‐wave radiation (λ = 365–577 nm) were also studied in this article. The results indicated that CPFDB moieties were significantly photolyzed under either full‐wave radiation or long‐wave radiation, thus undermining the controlled behavior of these RAFT processes. Whereas this photolysis was significantly suppressed under visible light radiation, thus CPFDB functionalities exerted well control over RAFT process, leading to a remarkably living behavior up to 90% GMA monomer conversions. This strategy facilitates the facile synthesis of well‐defined PGMA polymers. More importantly, under visible light radiation, a relatively high initial molar ratio of GMA to CPFDB and TPO led to shortening initialization period of RAFT process and accelerating overall polymerization rate. These effects are remarkably in favor of the facile synthesis of well‐defined PGMA polymers and PGMA‐based copolymers with high molecular weights. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5091–5102, 2007
Preparation, Tg improvement, and thermal stability enhancement mechanism of soluble poly(methyl methacrylate) nanocomposites by incorporating octavinyl polyhedral oligomeric silsesquioxanes
Authors: Xu Hongyao , Yang Benhong , Wang Jiafeng , Guang Shanyi , Li Cun
Published: October 2007

The soluble poly(methyl methacrylate‐co‐octavinyl‐polyhedral oligomeric silsesquioxane) (PMMA–POSS) hybrid nanocomposites with improved Tg and high thermal stability were synthesized by common free radical polymerization and characterized using FTIR, high‐resolution 1H NMR, 29Si NMR, GPC, DSC, and TGA. The POSS contents in the nanocomposites were determined based on FTIR spectrum, revealing that it can be effectively adjusted by varying the feed ratio of POSS in the hybrid composites. On the basis of the 1H NMR analysis, the number of the reacted vinyl groups on each POSS molecules was determined to be about 6–8. The DSC and TGA measurements indicated that the hybrid nanocomposites had higher Tg and better thermal properties than the pure PMMA homopolymer. The Tg increase mechanism was investigated using FTIR, displaying that the dipole–dipole interaction between PMMA and POSS also plays very important role to the Tg improvement besides the molecular motion hindrance from the hybrid structure. The thermal stability enhances with increase of POSS content, which is mainly attributed to the incorporation of nanoscale inorganic POSS uniformly dispersed at molecular level. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5308–5317, 2007
Synthesis and characterization of well‐defined, amphiphilic poly(N‐isopropylacrylamide)‐ b‐[2‐hydroxyethyl methacrylate‐poly(ϵ‐caprolactone)]n graft copolymers by RAFT polymerization and macromonomer method
Authors: Zhu Jing‐Ling , Zhang Xian‐Zheng , Cheng Han , Li Yong‐Yong , Cheng Si‐Xue , Zhuo Ren‐Xi
Published: October 2007

The well‐defined, thermosensitive and biodegradable graft copolymers, poly(N‐isopropylacrylamide)‐b‐[2‐hydroxyethyl methacrylate‐poly(ε‐caprolactone)]n (PNIPAAm‐b‐(HEMA‐PCL)n) (n = 3 or 9), were synthesized by combining reversible addition‐fragmentation chain transfer polymerization and macromonomer method. The copolymers were able to self‐assemble into micelles in water with low critical micellar concentration and demonstrated temperature sensitivity with a lower critical solution temperature at around 36 °C. Transmission electron microscopy shows that the micelles exhibit a nanosized spherical morphology within a size range of 30–100 nm. The PNIPAAm‐b‐(HEMA‐PCL)3 copolymer exhibited biodegradation and low cytotoxicity. The paclitaxel‐loaded PNIPAAm‐b‐(HEMA‐PCL)3 micelles displayed thermosensitive controlled release behavior, which indicates potential as drug carriers. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5354–5364, 2007
Synthesis and biological application of glycopolymers
Authors: Miura Yoshiko
Published: October 2007

Saccharides on the cell surfaces participate in a number of biochemical phenomena via the protein–saccharide interaction. Synthetic glycopolymers mimic the function of the cell‐surface saccharides and efficiently interact with proteins, cells, and pathogens based on the multivalent effect. Since the biological functions of saccharides are paid much attention, the glycopolymers are being increasingly explored as biomaterials for medicinal application and tissue engineering. This review presents a practical approach of glycopolymers. The glycopolymers were prepared by the facile syntheses of poly(vinyl saccharide)s and the physical and biological properties were introduced. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5031–5036, 2007
Deposition of Plasma‐Polymerized 1‐Cyanoisoquinoline Thin Films and Their Dielectric Properties
Authors: Zhao Xiong‐Yan , Wang Ming‐Zhu , Wang Zhi
Published: September 2007

A novel plasma‐polymerized 1‐cyanoisoquinoline (PPCIQ) thin film of desired thickness was prepared by plasma polymerization under different glow discharge conditions. The effect of the discharge power on the chemical structure, surface composition and morphology of the PPCIQ thin films were investigated by Fourier Transform Infrared (FTIR) Spectroscopy, X‐ray Photoelectron Spectroscopy (XPS), Atomic Force Microscopy (AFM) and deposition rate measurements. A high retention of the aromatic ring structure of the starting monomer in the deposited plasma films is obtained at a low discharge power of 15 W. The plasma‐synthesized films are homogeneous and quite suitable for the measurement of dielectric properties. The dielectric measurements show that a low dielectric constant of 2.62 has been obtained for the PPCIQ thin films for the first time.

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Covalently functionalized carbon nanotubes as macroinitiators for radical polymerization
Authors: Papagelis K. , Kalyva M. , Tasis D. , Parthenios J. , Siokou A. , Galiotis C.
Published: October 2007

Single‐walled carbon nanotubes were functionalized along their sidewalls with hydroxyalkyl groups using a radical addition scheme. These moieties were found to be active in the polymerization of acrylic acid from the surface of the nanotubes by a redox radical mechanism. The resulting polymerized nanotubes were analyzed by UV–Vis, XPS, Raman and SEM techniques. The composite material was found to be soluble in aqueous media (pH > 5) and polar organic solvents. The reported grafting technique is expected to be suitable for industrial production of modified carbon nanotubes. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Carbon nanotube based magnetic flux detector for molecular spintronics
Authors: Cleuziou J. P. , Wernsdorfer W. , Bouchiat V. , Ondarçuhu T. , Monthioux M.
Published: October 2007

This work describes the study of a superconducting quantum interference device (SQUID) with single‐walled carbon nanotube (CNT) Josephson junctions. Quantum confinement in each junction induces a discrete quantum dot (QD) energy level structure, which can be controlled with two lateral electrostatic gates. The gates are also used to directly tune the quantum phase interference of the Cooper pairs circulating in the SQUID ring. Optimal modulation of the switching current with magnetic flux is achieved when both QD junctions are in the ‘on’ or ‘off’ state. In particular, the SQUID design establishes that these CNT Josephson junctions can be used as gate‐controlled π junctions. Besides, the CNT‐SQUIDs are sensitive local magnetometers, which are very promising for the study of magnetization reversal of an individual magnetic particle or molecule placed on one of the two CNT Josephson junctions. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Solvation of excess electrons trapped in charge pockets on hydrated molecular surfaces
Authors: Jalbout Abraham F. , Contreras‐Torres Flavio , Castillo R. Del
Published: September 2007

We have previously computed a set of hypothetical molecular surfaces, which formed charge pockets that were capable of excess electron entrapment. These charge pockets arose due to the fact that the molecular surfaces possessed an extended network of OH groups on one side of the surface and hydrogen atoms on the opposite side. The uneven distribution of the OH groups coupled to the partial positive charge of the hydrogen atoms caused electrons to be attracted to the surface. In the present investigation we will consider the ability of the hydrogen cyanide (HCN)‐water complex in stabilizing excess electrons on molecular surfaces. The computed vertical detachment energy (VDE) values are high, suggesting anion stability. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
The hydroxyacetone (CH3COCH2(OH)) torsional potential and isomerization: A theoretical study
Authors: Jalbout Abraham F. , Contreras‐Torres Flavio F. , Adamowicz L.
Published: September 2007

In this work we explore the torsional potentials for hydroxyacetone using second order Møller‐Plesset (MP2) and coupled‐cluster (CCSD(T)) ab initio theoretical methods. We have calculated these potential energy surfaces as a function of single OH rotation, and simultaneous OH and methyl rotation. The results indicate that the low energy isomers coupled to the reduced barrier to methyl rotation can lead to several rotamers for this species to form. The values are compared to experimental quantities and implications for astrobiological research are also addressed. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Comparing the means and variances of a bivariate log‐normal distribution
Authors: Bebu Ionut , Mathew Thomas
Published: October 2007

For a bivariate log‐normal distribution, a confidence interval is developed for the ratio of the means. The generalized confidence interval approach is used for this purpose, and the procedure is applicable regardless of the sample size. It is also noted that the same approach can be used to obtain a confidence interval for the ratio of the variances. A modified signed log‐likelihood ratio procedure is also described for computing confidence intervals. The coverage probabilities of the proposed confidence intervals are estimated by Monte Carlo, and the generalized confidence intervals are found to exhibit satisfactory performance even for small sample sizes. Numerical results also show that the corresponding test procedures provide larger power compared with the modified signed log‐likelihood ratio test. Two examples are given: one dealing with the comparison of the means and variances of health‐care costs and the other dealing with testing mean equivalence in quantitative assays. Copyright © 2007 John Wiley & Sons, Ltd.
The design and use of WSDL‐Test: a tool for testing Web services
Authors: Sneed Harry M. , Huang Shihong
Published: September 2007

Web services are becoming increasingly important to many businesses, especially as an enabling technology for systems that adopt a service‐oriented architecture approach to their development. However, testing Web services poses significant challenges. This paper describes the design and use of WSDL‐Test, a tool designed specifically for this purpose. A key feature of WSDL‐Test is its ability to simulate the actual usage of Web services in a controlled environment. This enables WSDL‐Test to generate requests and validate responses in a rapid and reliable manner. To illustrate the use of WSDL‐Test, the paper also discusses our experience using the tool on a real‐world online eGoverment application. Copyright © 2007 John Wiley & Sons, Ltd.
Contemporary systems and complexity studies in China: review and prospect
Authors: Tong Wu
Published: October 2007

This paper presents the development of complexity and systems studies as proceeding along three stages: studies about systemic being and systemic structuralism, studies about systemic evolution and systemic historicism, complexity studies and post‐modernism. The paper also discusses the differences in complexity and systems studies between Chinese and Western researchers along three dimensions: ontological and epistemological emphases, objectivistic and subjectivistic assumptions and the ways of applying metaphors. The paper finally explores the value of pragmatism for complexity and systems studies. Copyright © 2007 John Wiley & Sons, Ltd.
Ascot Racecourse – Architektur trifft Tradition
Authors: Marinitsch Stefan , Sischka Johann
Published: October 2007

Ascot ist neben Wimbledon eines der sportlichen Großereignisse des Jahres. Während Royal Ascot besuchen täglich bis zu 80000 Personen die Pferderennen. International bekannt ist besonders der “Ladies Day”, wo jedes Jahr besonders extravagante Hutkreationen zu bewundern sind. Seit 2006 erstrahlt die Rennbahn im neuen Glanz. Kernstück dabei ist der neue Grand Stand, ein insgesamt 260 m langes Gebäude mit einer transparenten Glasfassade sowie einem geschwungenem Dach mit Blech‐ und Membranendeckung. Dieses ist geometrisch komplex und kragt bis zu 21 m über die Tribünen aus. Thema dieses Aufsatzes ist die Planung und Umsetzung der aufwendigen Dachkonstruktion unter Einhaltung eines sehr engen Terminrahmens.
Tragmodelle zur Bestimmung der Längsschubtragfähigkeit des Kronendübels als neuartiges Verbindungsmittel im Verbundbau
Authors: Fink Josef , Petraschek Thomas
Published: October 2007

Die geometrische Gestaltung des Kronendübels stellt eine neue Formgebung für eine Betondübelleiste dar und ist eine Entwicklung des Instituts für Tragkonstruktionen – Stahlbau der TU Wien. Ausgehend davon werden in diesem Beitrag zwei Tragmodelle zur Beschreibung des Tragvermögens einer solchen Schubverbindung mit allgemeiner Geometrie vorgestellt, deren Aufgabe die Sicherstellung der gemeinsamen Tragwirkung von Stahl‐ und Betonbauteil durch die Aufnahme des Schubflusses in der Kontaktfuge ist. Grundkonzept dieser Modelle ist, dass die Längsschubtragfähigkeit durch das Tragvermögen der vollkommen plastizierten Stahlkrone definiert wird. Der Vergleich mit einem experimentell erzielten Ergebnis zeigt, dass mittels der angeführten Modelle die Längsschubtragfähigkeit richtig prognostiziert werden kann. Zur Verifizierung des Tragmodells werden Ergebnisse einer nichtlinearen FE‐Analyse mit dem Programm ABAQUS angeführt.