bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of New Blue Anthracene‐based Conjugated Polymers and Their Applications in Polymer Light‐Emitting Diodes
Authors: Shih Hung‐Min , Lin Cheng‐Jui , Tseng Shin‐Rong , Lin Chih‐Hung , Hsu Chain‐Shu
Published: February 2011

A series of anthracene‐based conjugated copolymers containing 9,10‐bis(6‐bromonaphthalen‐2‐yl)‐2‐tert‐butylanthracene (BNA) and 2,7‐diphenyl substituted fluorene (DPPF) moieties are prepared via a palladium‐catalyzed Suzuki polymerization. All of the synthesized polymers emit blue light at around 450 nm and show good thermal and color stability. Their electroluminescence spectra remain unchanged at high driving voltage. The double‐layer polymer light‐emitting diode (PLED) fabricated with ITO/PEDOT:PSS/DPPFBNA3/CsF/Al, produces a maximum brightness of 1 650 cd · m−2 and has a luminance efficiency of 0.39 cd · A−1. The ITO/PEDOT:PSS/TFB/DPPFBNA3/CsF/Al multilayer PLED, incorporating a TFB layer to facilitate hole transportation, produces a maximum brightness of 5 371 cd · m−2 and a luminance efficiency of 1.18 cd · A−1.

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Castor‐Oil‐Based Waterborne Polyurethane Dispersions Cured with an Aziridine‐Based Crosslinker
Authors: Xia Ying , Larock Richard C.
Published: February 2011

Castor‐oil‐based anionic PU dispersions are post‐cured using a multiaziridine‐based crosslinker CX‐100. Thermal and mechanical properties of the resulting films are studied by DMA, DSC, TGA, and tensile tests. Mechanical properties are dramatically improved by the crosslinker. For example, the Young's modulus and tensile strength increase from 14.5 to 125 MPa and 13.1 to 18.1 MPa, respectively, when the aziridine fraction increases from 0 to 100%. The onset decomposition temperature of the films, T5, increases from 162 to 209 °C, indicating a significant increase in the thermal stability as the amount of aziridine is increased. This work provides an effective way of curing biorenewable anionic PU dispersions to prepare high performance, environmentally friendly coatings.

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Monte Carlo Simulation of Randomly Branched Step‐Growth Polymers: Generation and Analysis of Representative Molecular Ensembles
Authors: Hillegers L. Tom , Kapnistos Michael , Nijenhuis Atze , Slot Johan J. M. , Steeman Paul A. M.
Published: February 2011

A Monte Carlo simulation procedure has been set up and applied to generate representative ensembles of randomly branched step‐growth polymers based on their reaction recipe. The molecular distributions thus obtained are consistent with those from statistical/analytical approaches. However, because the current method gives access to the complete ensemble of simulated molecules, a very detailed structural analysis is possible. Our procedures are applicable to any ‘AfBg’ system with f + g ≥ 1. We apply this approach to randomly branched polyamides in order to gain insight into their molecular structure and understand the effect of the reaction recipe on the final product.

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Tissue‐engineered vascularized bone grafts: Basic science and clinical relevance to trauma and reconstructive microsurgery
Authors: Johnson Elizabeth O. , Troupis Theodore , Soucacos Panayotis N.
Published: February 2011

Bone grafts are an important part of orthopaedic surgeon's armamentarium. Despite well‐established bone‐grafting techniques, large bone defects still represent a challenge. Efforts have therefore been made to develop osteoconductive, osteoinductive, and osteogenic bone‐replacement systems. The long‐term clinical goal in bone tissue engineering is to reconstruct bony tissue in an anatomically functional three‐dimensional morphology. Current bone tissue engineering strategies take into account that bone is known for its ability to regenerate following injury, and for its intrinsic capability to re‐establish a complex hierarchical structure during regeneration. Although the tissue engineering of bone for the reconstruction of small to moderate sized bone defects technically feasible, the reconstruction of large defects remains a daunting challenge. The essential steps towards optimized clinical application of tissue‐engineered bone are dependent upon recent advances in the area of neovascularization of the engineered construct. Despite these recent advances, however, a gap from bench to bedside remains; this may ultimately be bridged by a closer collaboration between basic scientists and reconstructive surgeons. The aim of this review is to introduce the basic principles of tissue engineering of bone, outline the relevant bone physiology, and discuss the recent concepts for the induction of vascularization in engineered bone tissue. © 2011 Wiley‐Liss, Inc. Microsurgery, 2011.
Vascularized fibula transfer for lower limb reconstruction
Authors: Beris Alexandros E. , Lykissas Marios G. , Korompilias Anastasios V. , Vekris Marios D. , Mitsionis Gregory I. , Malizos Konstantinos N. , Soucacos Panayiotis N.
Published: February 2011

Massive bony defects of the lower extremity are usually the result of high‐energy trauma, tumor resection, or severe sepsis. Vascularized fibular grafts are useful in the reconstruction of large skeletal defects, especially in cases of scarred and avascular recipient sites, or in patients with combined bone and soft‐tissue defects. Microvascular free fibula transfer is considered the most suitable autograft for reconstruction of the middle tibia because of its long cylindrical straight shape, mechanical strength, predictable vascular pedicle, and hypertrophy potential. The ability to fold the free fibula into two segments or to combine it with massive allografts is a useful technique for reconstruction of massive bone defects of the femur or proximal tibia. It can also be transferred with skin, fascia, or muscle as a composite flap. Proximal epiphyseal fibula transfer has the potential for longitudinal growth and can be used in the hip joint remodeling procedures. Complications can be minimized by careful preoperative planning of the procedure, meticulous intraoperative microsurgical techniques, and strict postoperative rehabilitation protocols. This literature review highlights the different surgical techniques, indications, results, factors influencing the outcome, and major complications of free vascularized fibular graft for management of skeletal or composite defects of the lower limb. © 2011 Wiley‐Liss, Inc. Microsurgery, 2011.
Buttock reconstruction using a pedicled deep inferior epigastric perforator flap
Authors: Kim Kwang Seog , Kim Eui Sik , Hwang Jae Ha , Lee Sam Yong
Published: February 2011

Although deep inferior epigastric perforator (DIEP) flaps are mainly used for breast reconstruction as free flaps, they are also useful as pedicled island flaps. However, DIEP flaps have seldom been used for reconstructions in the lateral hip region. Furthermore, to the best of our knowledge, no report has been issued on the use of this flap for buttock reconstruction. The authors describe the successful use of a pedicled oblique DIEP flap for the reconstruction of a severe scar contracture in the buttock. The pedicled DIEP flap can be a useful option for the reconstruction of large buttock defects, and if a transverse DIEP flap is unavailable, an oblique DIEP flap should be considered an alternative. © 2011 Wiley‐Liss, Inc. Microsurgery, 2011.
Long‐term results after muscle‐rib flap transfer for reconstruction of composite limb defects
Authors: Georgescu Alexandru V. , Ignatiadis Ioannis , Ileana Matei , Irina Capota , Filip Ardelean , Olariu Radu
Published: February 2011

The authors present the long‐term results in a series of 44 cases with post‐traumatic bone defects solved with muscle‐rib flaps, between March 1997 and December 2007. In these cases, we performed 21 serratus anterior‐rib flaps (SA‐R), 10 latissimus dorsi‐rib flaps (LD‐R), and 13 LD‐SA‐R. The flaps were used in upper limb in 18 cases and in lower limb in 26 cases. With an overall immediate success rate of 95.4% (42 of 44 cases) and a primary bone union rate of 97.7% (43 of 44 cases), and despite the few partisans of this method, we consider that this procedure still remains very usefully for small and medium bone defects accompanied by large soft tissue defects. © 2011 Wiley‐Liss, Inc. Microsurgery, 2011.
Use of the descending branch of the lateral femoral circumflex vessels as a composite interposition graft in lower extremity reconstruction
Authors: Echo Anthony , Bullocks Jamal M.
Published: February 2011

The prevailing treatment for distal third lower extremity defects is with autologous free tissue transfers. In the trauma patient, these reconstructions are wrought with challenges, including the selection of appropriate recipient vessels, avoiding the zone of injury, and choosing the appropriate flap for transfer, all while maintaining perfusion to the foot. With distal defects and a large zone of injury, the free flap pedicle may need additional length to cover the defect and reach the recipient vessels without excess tension. The creation of an arteriovenous loop from an autologous vein graft is the usual solution. We present a case where additional pedicle length was needed to have a free flap completely cover a distal leg defect and connect to the anterior tibial vessels proximally. The saphenous vein was not available as an interposition graft; therefore, the descending branch of the lateral femoral circumflex artery and venae comitantes were used as a composite arteriovenous interposition graft. © 2011 Wiley‐Liss, Inc. Microsurgery, 2011.
MRI of blood flow of the human retina
Authors: Peng Qi , Zhang Yi , Nateras Oscar San Emeterio , van Osch Matthias J.P. , Duong Timothy Q.
Published: February 2011

This study reports a high‐resolution MRI approach to image basal blood flow and hypercapnia‐induced blood‐flow changes in the unanesthetized human retina on a 3‐T MRI scanner. Pseudocontinuous arterial spin labeling technique with static tissue suppression was implemented to minimize movement artifacts and improve blood‐flow sensitivity. Turbo spin–echo acquisition was used to achieve high spatial resolution free of susceptibility artifacts. The size, shape, and position of a custom‐made receive radiofrequency coil were optimized for sensitivity in the posterior retina. Synchronized eye blink and respiration to the end of each data readout minimized eye movement and physiological fluctuation. Robust high‐contrast blood‐flow MRI of the unanesthetized human retina was obtained at 500 × 800 μm2 in‐plane resolution. Blood flow in the posterior retina was 93 ± 31 mL/(100 mL min) (mean ± standard deviation, N = 5). Hypercapnic inhalation (5% CO2) increased blood flow by 12 ± 4% relative to air (P < 0.01, N = 5). This study demonstrates the feasibility of blood‐flow MRI of the retina of unanesthetized human. Because blood flow is tightly coupled to metabolic function under normal conditions and it is often perturbed in diseases, this approach could provide unique insights into retinal physiology and serve as an objective imaging biomarker for disease staging and testing of novel therapeutic strategies. This approach could open up new avenue of retinal research. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Real‐time motion correction for high‐resolution larynx imaging
Authors: Barral Joëlle K. , Santos Juan M. , Damrose Edward J. , Fischbein Nancy J. , Nishimura Dwight G.
Published: February 2011

Motion—both rigid‐body and nonrigid—is the main limitation to in vivo, high‐resolution larynx imaging. In this work, a new real‐time motion compensation algorithm is introduced. Navigator data are processed in real time to compute the displacement information, and projections are corrected using phase modulation in k‐space. Upon automatic feedback, the system immediately reacquires the data most heavily corrupted by nonrigid motion, i.e., the data whose corresponding projections could not be properly corrected. This algorithm overcomes the shortcomings of the so‐called diminishing variance algorithm by combining it with navigator‐based rigid‐body motion correction. Because rigid‐body motion correction is performed first, continual bulk motion no longer impedes nor prevents the convergence of the algorithm. Phantom experiments show that the algorithm properly corrects for translations and reacquires data corrupted by nonrigid motion. Larynx imaging was performed on healthy volunteers, and substantial reduction of motion artifacts caused by bulk shift, swallowing, and coughing was achieved. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Inflow‐based vascular‐space‐occupancy (iVASO) MRI
Authors: Hua Jun , Qin Qin , Donahue Manus J. , Zhou Jinyuan , Pekar James J. , van Zijl Peter C.M.
Published: February 2011

Vascular‐space‐occupancy (VASO) MRI, a blood nulling approach for assessing changes in cerebral blood volume (CBV), is hampered by low signal‐to‐noise ratio (SNR) because only 10–20% of tissue signal is recovered when using nonselective inversion for blood nulling. A new approach, called inflow‐VASO (iVASO), is introduced in which only blood flowing into the slice has experienced inversion, thereby keeping tissue and cerebrospinal fluid (CSF) signal in the slice maximal and reducing CSF partial volume effects. SNR increases of 198% ± 12% and 334% ± 9% (mean ± SD, n = 7) with respect to VASO were found at TR values of 5s and 2s, respectively. When using inflow approaches, data interpretation is complicated by the fact that signal changes are affected by vascular transit times. An optimal TR‐range (1.5–2.5s) was derived in which the iVASO response during activation predominantly reflects arterial/arteriolar CBV (CBVa) changes. In this TR‐range, perfusion contributions to the signal change are negligible because arterial label has not yet undergone capillary exchange, and arterial and precapillary blood signals are nulled. For TR = 2s, the iVASO signal change upon visual stimulation corresponded to a CBVa increase of 58% ± 7%, in agreement with arteriolar CBV changes previously reported. The onset of the hemodynamic response for iVASO occurred 1.2 ± 0.5s (n = 7) faster than for conventional VASO. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Echo‐planar imaging with prospective slice‐by‐slice motion correction using active markers
Authors: Ooi Melvyn B. , Krueger Sascha , Muraskin Jordan , Thomas William J. , Brown Truman R.
Published: February 2011

Head motion is a fundamental problem in functional magnetic resonance imaging and is often a limiting factor in its clinical implementation. This work presents a rigid‐body motion correction strategy for echo‐planar imaging sequences that uses micro radiofrequency coil “active markers” for real‐time, slice‐by‐slice prospective correction. Before the acquisition of each echo‐planar imaging‐slice, a short tracking pulse‐sequence measures the positions of three active markers integrated into a headband worn by the subject; the rigid‐body transformation that realigns these markers to their initial positions is then fed back to dynamically update the scan‐plane, maintaining it at a fixed orientation relative to the head. Using this method, prospectively‐corrected echo‐planar imaging time series are acquired on volunteers performing in‐plane and through‐plane head motions, with results demonstrating increased image stability over conventional retrospective image‐realignment. The benefit of this improved image stability is assessed in a blood oxygenation level dependent functional magnetic resonance imaging application. Finally, a non‐rigid‐body distortion‐correction algorithm is introduced to reduce the remaining signal variation. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Ischemia‐reperfusion injury in rat skeletal muscle assessed with T2‐weighted and dynamic contrast‐enhanced MRI
Authors: Loerakker S. , Oomens C. W. J. , Manders E. , Schakel T. , Bader D. L. , Baaijens F. P. T. , Nicolay K. , Strijkers G. J.
Published: February 2011

Pressure ulcers are localized areas of soft tissue breakdown due to mechanical loading. Susceptible individuals are subjected to pressure relief strategies to prevent long loading periods. Therefore, ischemia‐reperfusion injury may play an important role in the etiology of pressure ulcers. To investigate the inter‐relation between postischemic perfusion and changes in skeletal muscle integrity, the hindlimbs of Brown Norway rats were subjected to 4‐h ischemia followed by 2‐h reperfusion. Dynamic contrast‐enhanced MRI was used to examine perfusion, and changes in skeletal muscle integrity were monitored with T2‐weighted MRI. The dynamic contrast‐enhanced MRI data showed a heterogeneous postischemic profile in the hindlimb, consisting of areas with increased contrast enhancement (14–76% of the hindlimb) and regions with no‐reflow (5–77%). For T2, a gradual increase in the complete leg was observed during the 4‐h ischemic period (from 34 to 41 msec). During the reperfusion phase, a heterogeneous distribution of T2 was observed. Areas with increased contrast enhancement were associated with a decrease in T2 (to 38 msec) toward preischemic levels, whereas no‐reflow areas exhibited a further increase in T2 (to 42 msec). These results show that reperfusion after prolonged ischemia may not be complete, thereby continuing the ischemic condition and aggravating tissue damage. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Segmented 2D‐selective RF excitations with weighted averaging and flip angle adaptation for MR spectroscopy of irregularly shaped voxel
Authors: Finsterbusch Jürgen , Busch Martin G.
Published: February 2011

A weighted averaging scheme with flip angle adaptation is presented for segmented 2D‐selective RF excitations and applied to single‐line segments of a blipped‐planar trajectory. Segments covering the central k‐space, i.e. those with significant signal contributions, are averaged more often than the (outer) segments with low RF amplitudes and minor signal contributions. For compensation, these outer segments are applied with an increased RF amplitude, i.e. a larger flip angle, such that an unaltered signal contribution is obtained in a reduced number of shots. Numerical simulations and experiments in phantoms and the human brain in vivo demonstrate that the approach considerably increases the signal efficiency, i.e. the signal accumulated per time unit, without introducing profile distortions. Its application to single‐voxel MR spectroscopy of a corpus‐callosum‐shaped region‐of‐interest yielded, due to an optimum coverage of the target volume, higher signal amplitudes than conventional localization based on cross‐sectional RF excitations. Thus, the approach could improve the reliability of single‐voxel MR spectroscopy. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Traveling‐wave RF shimming and parallel MRI
Authors: Brunner David O. , Paška Jan , Froehlich Juerg , Pruessmann Klaas P.
Published: February 2011

At sufficiently high Larmor frequencies, traveling electromagnetic waves along a magnet bore can be used for remote magnetic resonance excitation and detection, effectively using the bore as a waveguide. So far, this approach has relied only on the lowest waveguide modes and thus has not supported multiple‐channel operation for radiofrequency shimming and parallel imaging. In this work, this limitation is addressed by establishing a larger number of propagating modes and tapping their spatial field diversity with multiple waveguide ports. The number of available modes is increased by loading with dielectric inserts; the ports are implemented by stub and loop couplers at the end of a waveguide extension. The resulting traveling‐wave array, operated at 298 MHz in a 7T whole‐body magnet, is shown to enable radiofrequency shimming as well as parallel imaging with commonly used acceleration factors. The last part of the study concerns the amount of dielectric loading that is required. For the given Larmor frequency and bore dimensions, it is found that rather few water‐filled inserts, occupying ∼5% of the bore cross‐section, are sufficient for effective parallel imaging. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Comparison of lung T2* during free‐breathing at 1.5 T and 3.0 T with ultrashort echo time imaging
Authors: Yu Jiangsheng , Xue Yiqun , Song Hee Kwon
Published: February 2011

Assessment of lung effective transverse relaxation time (T2*) may play an important role in the detection of structural and functional changes caused by lung diseases such as emphysema and chronic bronchitis. While T2* measurements have been conducted in both animals and humans at 1.5 T, studies on human lung at 3.0 T have not yet been reported. In this work, ultrashort echo time imaging technique was applied for the measurement and comparison of T2* values in normal human lungs at 1.5 T and 3.0 T. A 2D ultrashort echo time pulse sequence was implemented and evaluated in phantom experiments, in which an eraser served as a homogeneous short T2* sample. For the in vivo study, five normal human subjects were imaged at both field strengths and the results compared. The average T2* values measured during free‐breathing were 2.11(±0.27) ms at 1.5 T and 0.74(±0.1) ms at 3.0 T, respectively, resulting in a 3.0 T/1.5 T ratio of 2.9. Furthermore, comparison of the relaxation values at end‐expiration and end‐inspiration, accomplished through self‐gating, showed that during normal breathing, differences in T2* between the two phases may be negligible. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Atlas‐based knee cartilage assessment
Authors: Carballido‐Gamio Julio , Majumdar Sharmila
Published: February 2011

Magnetic resonance imaging analysis of knee cartilage properties at corresponding anatomic locations could be a valuable tool in studies of knee osteoarthritis by enabling accurate comparisons at practically any region. A technique of this kind is presented in this study. The proposed technique is based on gray‐level bone matching using affine transformations and free‐form deformations thus eliminating the need of bone segmentations and landmark matching. Sixteen subjects of the osteoarthritis initiative with knee osteoarthritis (10 from baseline; 6 from 24‐month follow‐up) were included in this study. Baseline subjects were used to create a gray‐level atlas of the patella with its corresponding mean cartilage thickness and T2 maps. Follow‐up subjects were used to validate atlas‐based point‐to‐point cartilage comparisons. All registrations were qualitatively evaluated with fused gray‐level images of registered patellas. Quantitative evaluation was performed based on mean values of minimum Euclidean distances between matched bone‐cartilage interfaces. A mean distance of 0.554 mm was obtained between the subjects used to build the atlas, and a mean distance of 0.633 mm was found between the atlas and validation subjects. The technique can be applied to other anatomical regions and with other cartilage measures. Qualitative and quantitative results demonstrate the accuracy of the technique and warrant its application in larger cross‐sectional and longitudinal studies of osteoarthritis. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Diffusion imaging with prospective motion correction and reacquisition
Authors: Benner Thomas , van der Kouwe André J. W. , Sorensen A. Gregory
Published: February 2011

A major source of artifacts in diffusion‐weighted imaging is subject motion. Slow bulk subject motion causes misalignment of data when more than one average or diffusion gradient direction is acquired. Fast bulk subject motion can cause signal dropout artifacts in diffusion‐weighted images and results in erroneous derived maps, e.g., fractional anisotropy maps. To address both types of artifacts, a fully automatic method is presented that combines prospective motion correction with a reacquisition scheme. Motion correction is based on the prospective acquisition correction method modified to work with diffusion‐weighted data. The images to reacquire are determined automatically during the acquisition from the imaging data, i.e., no extra reference scan, navigators, or external devices are necessary. The number of reacquired images, i.e., the additional scan duration can be adjusted freely. Diffusion‐weighted prospective acquisition correction corrects slow bulk motion well and reduces misalignment artifacts like image blurring. Mean absolute residual values for translation and rotation were <0.6 mm and 0.5°. Reacquisition of images affected by signal dropout artifacts results in diffusion maps and fiber tracking free of artifacts. The presented method allows the reduction of two types of common motion related artifacts at the cost of slightly increased acquisition time. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Combination of complex‐based and magnitude‐based multiecho water‐fat separation for accurate quantification of fat‐fraction
Authors: Yu Huanzhou , Shimakawa Ann , Hines Catherine D. G. , McKenzie Charles A. , Hamilton Gavin , Sirlin Claude B. , Brittain Jean H. , Reeder Scott B.
Published: February 2011

Multipoint water–fat separation techniques rely on different water–fat phase shifts generated at multiple echo times to decompose water and fat. Therefore, these methods require complex source images and allow unambiguous separation of water and fat signals. However, complex‐based water–fat separation methods are sensitive to phase errors in the source images, which may lead to clinically important errors. An alternative approach to quantify fat is through “magnitude‐based” methods that acquire multiecho magnitude images. Magnitude‐based methods are insensitive to phase errors, but cannot estimate fat‐fraction greater than 50%. In this work, we introduce a water–fat separation approach that combines the strengths of both complex and magnitude reconstruction algorithms. A magnitude‐based reconstruction is applied after complex‐based water–fat separation to removes the effect of phase errors. The results from the two reconstructions are then combined. We demonstrate that using this hybrid method, 0–100% fat‐fraction can be estimated with improved accuracy at low fat‐fractions. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Detection of neuronal current MRI in human without BOLD contamination
Authors: Luo Qingfei , Jiang Xia , Gao Jia‐Hong
Published: February 2011

Controversial results regarding the detectability of neuronal current magnetic resonance imaging (ncMRI) have been reported in different studies on human subjects. In all the previous studies, the ncMRI signal was detected under a continuous and paradigm task‐induced blood oxygen level dependent (BOLD) signal background. The aim of this study is to investigate the possibility of detecting ncMRI signal in human brain in the situation that task‐induced BOLD background is absent or minimum. In this study, by adopting an event‐related visuomotor paradigm with long interstimulus interval (=20 s), the ncMRI signal was detected when the BOLD signal fully returned to its baseline, and the potential BOLD background contamination was avoided effectively. The results showed that the visuomotor stimulation elicited BOLD activation in visual and motor cortices, but no significant ncMRI signal change (in magnitude) was detected in human brain. These experimental findings are consistent with theoretical predications. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Determination of the optimal first‐order gradient moment for flow‐sensitive dephasing magnetization‐prepared 3D noncontrast MR angiography
Authors: Fan Zhaoyang , Zhou Xiangzhi , Bi Xiaoming , Dharmakumar Rohan , Carr James C. , Li Debiao
Published: February 2011

Flow‐sensitive dephasing (FSD) magnetization preparation has been developed for black‐blood vessel wall MRI and noncontrast MR angiography. The first‐order gradient moment, m1, is a measure of the flow‐sensitization imparted by an FSD preparative module. Determination of the optimal m1 for each individual is highly desirable for FSD‐prepared MR angiography. This work developed a 2D m1‐scouting method that evaluates a range of m1 values for their effectiveness in blood signal suppression in a single scan. The feasibility of using the 2D method to predict blood signal suppression in 3D FSD‐prepared imaging was validated on a flow phantom and the popliteal arteries of 5 healthy volunteers. Excellent correlation of the blood signal measurements between the 2D scouting and 3D FSD imaging was obtained. Therefore, the optimal m1 determined from the 2D m1‐scouting scan may be directly translated to 3D FSD‐prepared imaging. In vivo studies of additional 10 healthy volunteers and 2 patients have demonstrated the proposed method can help significantly improve the signal performance of FSD MR angiography, indicating its potential to enhance diagnostic confidence. Further systematic studies in patients are warranted to evaluate its clinical value. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Unilateral calf atrophy secondary to a de novo mutation of the caveolin‐3 gene
Authors: Arias Gómez Manuel , Alberte‐Woodwar Miguel , Arias‐Rivas Susana , Dapena Dolores , Pintos Elena , Navarro Carmen
Published: February 2011

A 23‐year‐old man was evaluated for atrophy of the left calf. He had a myopathic pattern on electromyography. Light microscopy showed dystrophic changes and reduced immunostaining for dysferlin and caveolin‐3. The subsarcolemmal space was enlarged, and abnormal vesicles were visible with electron microscopy. A genetic study showed a heterozygous A45T mutation at exon 2 of the caveolin‐3 gene. Such a mutation has been reported previously with limb‐girdle muscular dystrophy type 1C and rippling muscle disease phenotypes. Muscle Nerve 44: 126–128, 2011.
A mesh adaptation procedure for periodic domains
Authors: Dobrzynski Cécile , Melchior Maxime , Delannay Laurent , Remacle Jean‐François
Published: February 2011

In this paper, an original technique is developed in order to build adaptive meshes on periodic domains. The new approach has the important property that it is code‐reused. The procedure is used against three different algorithms, namely, MAdLib ( Int. J. Numer. Meth. Engng 2000; in press), mmg (Proc. 17th Int. Meshing Roundtable, 2008) and the couple Yams (Rapport Technique RT‐0252, 2001) /Ghs3d (Proc. 8th Int. Meshing Roundtable, 1999). None of the latter algorithms needs to be adapted before it is applied to periodic domains. Some examples of adaptation are presented based on analytical, isotropic and anisotropic mesh‐size fields. Periodicity in translation and rotation both are considered. Finally, the mesh adaptation strategy is used in order to reduce the computational cost of a prediction of strain heterogeneity throughout a periodic polycrystalline aggregate deforming by dislocation slip. Copyright © 2011 John Wiley & Sons, Ltd.
Explicit finite element artificial boundary scheme for transient scalar waves in two‐dimensional unbounded waveguide
Authors: Zhao Mi , Du Xiuli , Liu Jingbo , Liu Heng
Published: February 2011

To simulate the transient scalar wave propagation in a two‐dimensional unbounded waveguide, an explicit finite element artificial boundary scheme is proposed, which couples the standard dynamic finite element method for complex near field and a high‐order accurate artificial boundary condition (ABC) for simple far field. An exact dynamic‐stiffness ABC that is global in space and time is constructed. A temporal localization method is developed, which consists of the rational function approximation in the frequency domain and the auxiliary variable realization into time domain. This method is applied to the dynamic‐stiffness ABC to result in a high‐order accurate ABC that is local in time but global in space. By discretizing the high‐order accurate ABC along artificial boundary and coupling the result with the standard lumped‐mass finite element equation of near field, a coupled dynamic equation is obtained, which is a symmetric system of purely second‐order ordinary differential equations in time with the diagonal mass and non‐diagonal damping matrices. A new explicit time integration algorithm in structural dynamics is used to solve this equation. Numerical examples are given to demonstrate the effectiveness of the proposed scheme. Copyright © 2011 John Wiley & Sons, Ltd.
Linking home care interventions and hospitalization outcomes for frail and non‐frail elderly patients
Authors: Monsen Karen A. , Westra Bonnie L. , Oancea S. Cristina , Yu Fang , Kerr Madeleine J.
Published: February 2011

Structured clinical data generated using standardized terminologies such as the Omaha System are available for evaluating healthcare quality and patient outcomes. New intervention management grouping approaches are needed to deal with large, complex clinical intervention data sets. We evaluated 56 intervention groups derived using four data management approaches with a data set of 165,700 interventions from 14 home care agencies to determine which approaches and interventions predicted hospitalizations among frail (n = 386) and non‐frail (n = 1,364) elders. Hospitalization predictors differed for frail and non‐frail elders. Low frequencies in some intervention groups were positively associated with hospitalization outcomes, suggesting that there may be a mismatch between the level of care that is needed and the level of care that is provided. © 2011 Wiley Periodicals, Inc. Res Nurs Health
Trajectories of depressive symptoms from adolescence to young adulthood: Chinese Americans versus non‐hispanic whites
Authors: Chen Angela Chia‐Chen , Haas Steven , Gillmore Mary Rogers , Kopak Albert
Published: February 2011

We examined age, sex, and race/ethnicity differences in trajectories of depressive symptom from adolescence to early adulthood; we also tested whether socioeconomic status and acculturation were associated with the differences. The findings suggest that adolescents over age 15 had a higher level and faster decline in depressive symptoms than their younger counterparts; females had higher level and a faster decline in depressive symptoms than males. Chinese American females had the highest depressive symptoms sustained across 7 years; Chinese American males over age 15 had higher depressive symptoms than their White male counterparts. Neither socioeconomic status nor acculturation was significantly associated with the differences in the trajectories. Our findings suggest a need for greater attention to Chinese American adolescents' psychological well‐being. © 2011 Wiley Periodicals, Inc. Res Nurs Health 34:176–191, 2011
Family caregivers of hospitalized adults in Israel: A point‐prevalence survey and exploration of tasks and motives
Authors: Auslander Gail K.
Published: February 2011

The prevalence of family inpatient caregiving in Israel, its extent, content, and related caregiver and patient variables were examined. Of 1,076 patients surveyed, 744 (69%) had family caregivers, and 513 caregivers were interviewed. Caregivers averaged 8 hours a day at the hospital and most frequently carried out monitoring tasks. Their main motivation was the desire to help the patient. Variables that explained overall caregiving tasks were the desire to help the patient (β = .38), to ensure quality of care (β = .19) and external pressure (β = .19). Variables that explained number of hours spent in caregiving were patient's age (β = −.28) and caregiver motivation related to benefits (β = −.19) and separation concerns (β = .18). Staff should identify caregivers, assess their motivations, and help determine appropriate tasks. © 2011 Wiley Periodicals, Inc. Res Nurs Health 34:204–217, 2011
Understanding donors: A case of university performing arts programs in the USA
Authors: Ko Yong Jae , Gibson Heather , Kim May
Published: February 2011

The purpose of the study was to: (a) to examine the factors that influence donor behavior, (b) to determine which specific perceived benefits are predictors of donor behavior, and (c) to examine the influence of gender, age, and income level of university performing arts program (PAP) donors. Secondary data from the Value and Impact Study, collected by 14 Major University Presenters (MUPs) was used. Results of data analyses using 1771 donor responses suggest that identification with the PAP, familiarity with planned giving options, and public recognition are important predictors of donor behavior. Donors highly value priority seating, advanced notice of programs, and ability to purchase single tickets in advance of public sale. Additionally, age, gender, economic status, and perceived benefits were found to be important variables for understanding donor behavior. Given these results, implications for future research and practice in relationship marketing are discussed.

Copyright © 2011 John Wiley & Sons, Ltd.
Five direct marketing strategies for nonprofit organisations
Authors: Saxton Joe
Published: February 2011

This paper outlines five direct marketing strategies which nonprofit organisations are following; Donation‐led, Intimacy, Audience‐led, Product‐led and Multi‐product. The purpose in identifying these strategies is to show that nonprofit organisations have a greater range of strategic choices than is often assumed. The second part of the paper looks at the building blocks for a successful direct marketing strategy and shows how they differ between the five strategies.

Direct marketing is used as a generic term throughout this paper. Relationship marketing is used to indicate relationship building, as opposed to simply communicating directly.
The impact of the internet upon fundraising
Authors: Whiteley Michael , Baker John
Published: February 2011

Through research on a sample of the top 2000 charities, the Voluntary Organisations Internet Server (VOIS) revealed the potential for a major initiative to provide the opportunity for voluntary organisations to create a quality brand of information on the Internet by coming together on a collective site. The Internet is an ideal medium for voluntary organisations to get their message across, build relationships and raise funds. VOIS has been designed specifically to facilitate these activities and provide the means to a collective presence. While it is mainly large organisations that are using it at the moment, the Internet represents the opportunity for smaller organisations to have a substantial presence because of its democratic nature. VOIS has utilised the principle of economies of scale in order that all organisations can afford to have a useful presence on the Internet. This paper will examine fundraising activities that are already occurring on the Internet, analyse the strengths of the Internet as a marketing tool, explain how marketers can utilise these strengths and explain how VOIS has tried to facilitate these strengths within the features of its standardised site.
Electronic mail as a fundraising tool
Authors: Lake Howard
Published: February 2011

The World Wide Web has attracted considerable attention and investment in the for‐profit and nonprofit worlds, but electronic mail (e‐mail) alone can be one of the most effective online fundraising and marketing tools. Its use in fundraising appeals is considered and its relationship to traditional direct mail fundraising discussed. Other more innovative methods of incorporating e‐mail into a fundraising mix are explored, including the basic applications of an e‐mail signature to the more advanced uses of automated e‐mail response systems.

This paper is based on research carried out by the author at City University during 1994 and 1995 as part of an MSc course in Information Science and published as ‘Electronic sources of fundraising information for UK nonprofit fundraisers’.
Legal update
Authors: Norton Philip
Published: February 2011

This update covers developments in relation to UK charity law, particularly in relation to fundraising and other marketing strategies. Future issues will consider legal updates in the United States and Europe.

If readers have any particular questions on charity law, please write to Philip Norton at the Publisher's offices, so that he can answer questions that are of general interest to readers.
Markets for emission permits with free endowment: A vintage capital analysis
Authors: Bréchet Thierry , Tsachev Tsvetomir , Veliov Vladimir M.
Published: February 2011

In this paper, we develop a vintage capital model for a firm involved in a market for tradable emission permits. We analyze both the firm's optimal investment plans and the market equilibrium. This allows us to scrutinize how firms use permits free endowment, and to highlight the implications of non‐optimal uses both at the firm and at the market level. We provide a new rationale for the market of tradable permits not to be cost‐efficient. The novel technical points in this context are the use of a distributed (vintage) optimal control model of the firm, the use of optimality conditions for non‐smooth problems, and the involvement of a nonlinear Fredholm integral equation of the first kind for the description of the equilibrium price of permits, and its practical meaning for market regularization. Copyright © 2011 John Wiley & Sons, Ltd.
Influenzaviren auf dem Weg vom Tier zum Menschen. Grippeausbrüche
Authors: Klenk Hans‐Dieter
Published: February 2011

Influenza‐A‐Viren kommen in großer Vielfalt bei Wasservögeln vor und werden von dort gelegentlich auf andere Tiere sowie auf den Menschen übertragen. In einem komplizierten Anpassungsprozess kann so in seltenen Fällen ein neues human‐pathogenes Virus entstehen, das sich dann pandemisch ausbreitet. In den letzten 100 Jahren kam es auf diese Weise zu mindestens fünf Pandemien einschließlich des H1N1‐Ausbruchs im Jahre 2009. Aus den pandemischen Viren gehen durch Mutationen die saisonalen Erreger hervor, die die jährlichen Grippeepidemien verursachen. Vereinzelte Übertragungen von H5N1‐Viren auf den Menschen haben bislang nicht zu einer Pandemie geführt.
Influenzaviren: Biologie und Pathogenitätsfaktoren. Erreger saisonaler Epidemien und weltweiter Pandemien
Authors: Michaelis Martin
Published: February 2011

Trotz langjähriger Forschung auf dem Gebiet der Influenzaviren bleiben bis heute viele Fragen bezüglich der molekularen Vorgänge im Rahmen der Influenzavirusreplikation und ‐biologie offen. Dieser Umstand wird insbesondere dadurch verdeutlicht, dass in den letzten drei Jahren zwei neue Influenzaproteine (PB1‐F2, PB1‐N40) entdeckt wurden, deren Funktionen und Bedeutungen insbesondere im Fall von PB1‐N40 noch unverstanden sind. Diese Lücken im Verständnis der Influenzaviren und der durch sie verursachten Erkrankungen begrenzen naturgemäß die Möglichkeiten, verlässliche Vorhersagen über die Entwicklung neuer Viren und die Entstehung neuer Pandemien (und entsprechende spezifische Vorsorgemaßnahmen) zu treffen. Daher ist auf diesem Gebiet weitere intensive Forschung notwendig, insbesondere mit Schwerpunkten auf der Heterogenität und Diversität der Influenzaviren und der Virus‐Wirtszellinteraktionen in unterschiedlichen Zelltypen.
Die neuen (drohenden?) Grippe‐Pandemien. Von der Vogelgrippe H5N1 zur Schweinegrippe H1N1
Authors: Zündorf Ilse , Dingermann Theo
Published: February 2011

Seit den letzten großen Grippe‐Pandemien im 20. Jahrhundert überwacht die Weltgesundheitsorganisation sehr sorgfältig das Auftreten neuer Influenza‐Virus‐Subtypen. Das Vogelgrippe‐Virus H5N1 hat 2005/2006 die Welt in Alarmbereitschaft versetzt. Infolgedessen verfügt nun jedes Land und in Deutschland zusätzlich jedes Bundesland über einen eigenen Pandemieplan. Aber es war nicht das Vogelgrippevirus H5N1, sondern ein neues H1N1‐Virus, das 2009 für eine Generalprobe der Maßnahmen sorgte. Mittlerweile befinden wir uns in der Post‐Pandemic‐Period und wir wissen jetzt, dass glücklicherweise alles recht glimpflich abgelaufen ist. Es hätte aber auch alles sehr viel schlimmer kommen können. Daher war die oftmals bagatellisierende Berichterstattung gegen Ende der Pandemiephase in hohem Maße populistisch und verantwortungslos.
Zur Herstellung von Influenza‐Impfstoffen auf MDCK‐Zellkulturen. Zellkultur versus Ei
Authors: Bruckhoff Berthold
Published: February 2011

Während bei einigen Impfstoffen gegen virale Infektionen (z.B. MMR, Rabies, FSME) die Herstellung mittels Zellkulturen ein bereits lang genutzter und gut etablierter Prozess ist, werden Influenza‐Impfstoffe noch immer über das wenig standardisierbare Medium Hühnereier produziert. Durch den Einsatz einer permanenten MDCK‐Zelllinie kann die aufwendige und sensible Produktion auf Eiern durch einen robusten, standardisierten und geschlossenen Herstellungungsprozess ersetzt werden. Dadurch steht ein Influenza‐Impfstoff mit einer hohen Reinheit zur Verfügung, der auch bei Hühnerei‐ oder Antibiotika‐Allergikern eingesetzt werden kann. Das Herstellungsverfahren über MDCK‐Zellkulturen ist für die saisonalen Influenza‐Vakzine Optaflu bereits zugelassen und wurde darüber hinaus auch für den pandemischen Impfstoff Celtura kommerziell genutzt.
M2‐Inhibitoren und Neuraminidase‐Inhibitoren. Wirkstoffe gegen Grippe
Authors: Klebe Gerhard , Schlitzer Martin
Published: February 2011

Die ersten Grippetherapeutika waren die M2‐Hemmstoffe Amantadin und Rimantadin. Aufgrund weitreichender Resistenzen hat sich ihr Wert mittlerweile deutlich reduziert. Neuraminidase‐Inhibitoren sind ein schönes Beispiel für ein erfolgreiches strukturbasiertes Wirkstoffdesign. Jedoch nehmen auch hier die Resistenzen zu. Neuraminidase‐Inhibitoren werden kontinuierlich weiterentwickelt. Hier befinden sich die Wirkstoffentwickler in einem Wettlauf mit der Wandlungsfähigkeit des Virus.
Wie sicher war die Oseltamivir‐Versorgung in Zeiten der Grippe‐Pandemie? Industrielle Oseltamivir‐Synthese
Authors: Holzgrabe Ulrike
Published: February 2011

Die Synthese des stereochemisch anspruchsvollen Oseltamivir ist an sich schon eine Herausforderung. Im Fall der Grippepandemien muss der Arzneistoff in kürzester Zeit im Tonnenmaßstab hergestellt werden. Nur Hoffmann‐La Roche, die über die Lizenz für Oseltamivir verfügen, war in der Lage, diese Herausforderung zu bewältigen. Obgleich die anfänglich kalkulierten 400 Millionen Therapiezyklen nicht hergestellt worden sind, hat nie Knappheit an Oseltamivir bestanden.
RNA‐Interferenz‐Test zur Auffindung neuer Targets. Neuartige Hochdurchsatz‐Screening‐Technik
Authors: Schmitz Jens
Published: February 2011

Mittels RNA‐Interferenz kann die Expression spezifischer Gene sehr effizient reguliert bzw. komplett inhibiert werden. Durch den Einsatz von genomweiten RNA‐Interferenz‐Screening‐Techniken im Hochdurchsatzverfahren können auf diese Weise humane Gene identifiziert werden, die für zentrale biologische Prozesse in Zellen verantwortlich sind und die Basis zum Verständnis molekularer Ursachen humaner Krankheiten bilden. Außerdem können neue Zielstrukturen für Wirkstoffe, z.B. gegen Influenzavirus‐Infektionen, entdeckt werden. Dies macht die Entwicklung neuer erfolgversprechender Therapiestrategien möglich.
Gefäßzerstörung in der Tumortherapie
Authors: Berger S. , Bourdy S. , Hergaden B. , Schmitt J. , Zündorf I. , Dingermann T.
Published: February 2011

Ein recht erfolgreicher Ansatz in der Tumortherapie ist die Inhibition der Angiogenese. Hierfür sind bereits einige Wirkstoffe auf dem Markt. Nun wird mit der Zerstörung bereits bestehender Gefäße auch noch ein anderes Therapiekonzept verfolgt. Für die neue Wirkstoffgruppe wurde auch ein passendes Kürzel gefunden: VDA für vascular disrupting agents.
Proteinflexibilität der Neuraminidase öffnet neue Möglichkeiten für die Wirkstoffentwicklung
Authors: von Grafenstein Susanne , Liedl Klaus R.
Published: February 2011

Obwohl bereits Neuraminidase‐Inhibitoren auf dem Markt sind, bleibt das Oberflächenprotein Neuraminidase weiterhin ein spannendes Forschungsobjekt, denn Einblicke in die Proteinflexibilität bieten neue Möglichkeiten für die Entwicklung von Neuraminidase‐Inhibitoren.