bluuebunny/crossref_metadata_2025_split huggingface dataset:
Correction of gradient‐induced phase errors in radial MRI
Authors: Moussavi Amir , Untenberger Markus , Uecker Martin , Frahm Jens 
Published: February 2013

PurposeTo correct gradient‐induced phase errors in radial MRI.MethodsGradient‐induced eddy currents affect the MRI data acquisition by gradient delays and phase errors that may lead to severe image artifacts for non‐Cartesian imaging scenarios such as radial trajectories. While gradient delays are dealt with by respective shifts of the acquisition window during radial image acquisition, this work introduces a simple method for quantifying and correcting phase errors from the actual data prior to image reconstruction. For a given gradient system, the approach yields a specific phase error per gradient that can be used for correcting the raw data.ResultsPhantom studies at 9.4 T demonstrated marked improvements in radial image quality. It could be shown that the phase correction is not compromised by data undersampling. Moreover, the selective correction of gradient‐induced phase errors retained the phase information caused by different concentrations of a paramagnetic contrast agent.ConclusionThe proposed method does not require additional reference measurements and separately corrects for phase errors induced by eddy currents, while retaining the residual phase of the object which may carry physiologic information. Magn Reson Med 71:308–312, 2014. © 2013 Wiley Periodicals, Inc.
Analysis and correction of biases in cross‐relaxation MRI due to biexponential longitudinal relaxation
Authors: Mossahebi Pouria , Yarnykh Vasily L. , Samsonov Alexey 
Published: February 2013

PurposeCross‐relaxation imaging (CRI) is a family of quantitative magnetization transfer techniques that utilize images obtained with off‐resonance saturation and longitudinal relaxation rate (R1) maps reconstructed by the variable flip angle (VFA) method. It was demonstrated recently that a significant bias in an apparent VFA R1 estimation occurs in macromolecule‐rich tissues due to magnetization transfer (MT)‐induced biexponential behavior of longitudinal relaxation of water protons. The purpose of this article is to characterize theoretically and experimentally the resulting bias in the CRI maps and propose methods to correct it.TheoryThe modified CRI algorithm is proposed, which corrects for such biases and yields accurate parametric bound pool fraction f, cross‐relaxation rate k, and R1 maps. Additionally, an analytical correction procedure is introduced to recalculate previously obtained parameter values.ResultsThe systematic errors due to unaccounted MT‐induced biexponential relaxation can be characterized as an overestimation of R1, f, and k, with a relative bias comparable with the magnitude of f. The phantom and human in vivo experiments demonstrate that both proposed modified CRI and analytical correction approaches significantly improve the accuracy of the CRI method.ConclusionThe accuracy of the CRI method can be considerably improved by taking into account the contribution of MT‐induced biexponential longitudinal relaxation into variable flip angle R1 measurements. Magn Reson Med 71:830–838, 2014. © 2013 Wiley Periodicals, Inc.
Quick water‐selective excitation of fast relaxing tissues with 3D UTE sequences
Authors: Springer Fabian , Steidle Günter , Martirosian Petros , Grosse Ulrich , Syha Roland , Schabel Christoph , Claussen Claus D. , Schick Fritz 
Published: February 2013

PurposeThe aim of this study was to implement a time effective 1‐1 double pulse water‐selective excitation (WE) into a three‐dimensional ultrashort echo time (UTE) sequence (WE‐UTE) for visualization of short‐T2 tissues with positive contrast and sufficient suppression of surrounding fat.MethodsFirst, an analytical description of magnetization components in the steady state applying WE‐UTE was derived and results were compared with numerical simulations based on Bloch's equations. Parameters were optimized for best positive contrast between short‐T2 tissues and fat under consideration of variable relaxation properties over a broad range. Maximal signal yield and signal efficiency of on‐resonant protons were compared with UTE sequences with and without off‐resonance fat saturation (FatSat). WE‐UTE was exemplarily applied for in‐vivo musculoskeletal imaging on a 3T whole‐body MR unit.ResultsSteady state magnetization of WE‐UTE could be described analytically and showed excellent accordance with numerical simulations. Even for tissues with T2 = 1 ms WE‐UTE resulted in 79% of maximal signal yield of UTE without FatSat and was more efficient regarding signal yield if compared with UTE with FatSat. Using WE‐UTE in‐vivo tendons and ligaments could be well delineated with positive contrast to surrounding fat.ConclusionWE‐UTE provides a quick method for visualizing short‐T2 tissues with positive contrast. Magn Reson Med 71:534–543, 2014. © 2013 Wiley Periodicals, Inc.
Three‐dimensional mapping of the creatine kinase enzyme reaction rate in muscles of the lower leg
Authors: Parasoglou Prodromos , Xia Ding , Chang Gregory , Convit Antonio , Regatte Ravinder R. 
Published: February 2013

Phosphorus (31P) magnetization transfer (MT) techniques enable the non‐invasive measurement of metabolic turnover rates of important enzyme‐catalyzed reactions, such as the creatine kinase reaction (CK), a major transducing reaction involving adenosine triphosphate and phosphocreatine. Alteration in the kinetics of the CK reaction rate appears to play a central role in many disease states.In this study, we developed and implemented at ultra‐high field (7T) a novel three‐dimensional 31P‐MT imaging sequence that maps the kinetics of CK in the entire volume of the lower leg at relatively high resolution (0.52 mL voxel size), and within acquisition times that can be tolerated by patients (below 60 min). We tested the sequence on five healthy and two clinically diagnosed type 2 diabetic subjects. Overall, we obtained measurements that are in close agreement with measurements reported previously using spectroscopic methods. Importantly, our spatially resolved method allowed us to measure local CK reaction rate constants and metabolic fluxes in individual muscles in a non‐invasive manner. Furthermore, it allowed us to detect variations of the CK rates of different muscles, which would not have been possible using unlocalized MRS methods.The results of this work suggest that 3D mapping of the CK reaction rates and metabolic fluxes can be achieved in the skeletal muscle in vivo at relatively high spatial resolution and with acquisition times well tolerated by patients. The ability to measure bioenergetics simultaneously in large areas of muscles will bring new insights into possible heterogeneous patterns of muscle metabolism associated with several diseases and serve as a valuable tool for monitoring the efficacy of interventions. Copyright © 2013 John Wiley & Sons, Ltd.
Innovation in Global Collaborations: From Student Placement to Mutually Beneficial Exchanges
Authors: Suarez‐Balcazar Yolanda , Hammel Joy , Mayo Liliana , Inwald Stephanie , Sen Supriya 
Published: February 2013

AbstractFive years ago, an academic department in the United States and the Ann Sullivan Center of Peru (CASP) initiated an international partnership to foster research collaborations and reciprocal consultation, and to create an advanced clinical placement for occupational therapy doctoral students. CASP is a globally recognized hub for community‐based research, demonstration and training for people with disabilities (most of whom are from low‐income families). CASP has provided occupational therapy students and faculty with a rich cultural environment in which to learn and collaborate as well as opportunities for developing research collaborations. The purpose of this manuscript is to discuss an innovative model of international collaboration highlighting specific areas of exchange and reciprocal learning. First, we will describe the collaboration and CASP's rich learning opportunities. Second, we will discuss a model of collaboration that includes three main phases: planning and preparation, developing and sustaining the partnership, and evaluating and celebrating outcomes and benefits. We illustrate the partnership with a case example and describe exchanges between CASP and a local community agency with whom faculty have collaborated for 20 years. Finally, we discuss implications of our innovative model towards developing and sustaining global partnerships. Copyright © 2013 John Wiley & Sons, Ltd.
Patient‐perceived facilitators in the transition of care for young adult survivors of childhood cancer
Authors: Sadak Karim Thomas , DiNofia Amanda , Reaman Gregory 
Published: February 2013

AbstractBackgroundA new challenge has emerged in optimizing the transition of pediatric survivorship care to similarly focused programs that are age‐appropriate for young adults. The purpose of this study is to identify components of a clinical survivorship program that facilitate the transition of care for young adult survivors of childhood cancer from a pediatric to adult care‐setting.ProcedurePrior to transition, a descriptive study of childhood cancer survivors was conducted using a cross‐sectional study design. A questionnaire was used to identify which clinical components of a survivorship program would most influence their decision to transition care to an adult medical center.ResultsOf 129 invited survivors, 103 participated (80%). Most survivors were age 16–19 years (40/103, 39%) or 20–24 years (37/103, 36%). When asked if the participant was willing to transition their survivorship care to an adult facility, 97 (95%) responded affirmatively. The clinical components most frequently rated “Very Important” in the decision to transition were the acceptance of insurance (80/103, 78%) followed by the presence of a provider knowledgeable in childhood cancer (68/103, 66%). The clinical components most frequently rated “Very Important” or “Important” were the availability of flexible scheduling (102/103, 99%) followed by the comprehensive nature of the care provided (101/103, 98%).ConclusionsThe decision to transition survivorship care to age‐appropriate care‐settings is complex and not well understood. Issues related to insurance, clinical team composition and scheduling appear to be most important for young adult survivors making this decision. Pediatr Blood Cancer 2013;601365‐1368. © 2013 Wiley Periodicals, Inc.
MPL W515L mutation in pediatric essential thrombocythemia
Authors: Farruggia Piero , D'Angelo Paolo , La Rosa Maria , Scibetta Nunzia , Santangelo Giuseppe , Lo Bello Antonio , Duner Elena , Randi Maria Luigia , Putti Maria Caterina , Santoro Alessandra 
Published: February 2013

AbstractEssential thrombocythemia (ET) is extremely rare in the pediatric population. In most patients no molecular abnormality can be found, with about 40% of pediatric patients harboring a JAK2 V617F mutation. Another recurrent mutation, involving a W to L or K transversion at MPL codon 515, has been reported in about 3–8% of adult ET patients. Herein we describe this mutation in a pediatric patient. Pediatr Blood Cancer 2013;60E52‐E54. © 2013 Wiley Periodicals, Inc.
Enhanced photovoltaic performance of cross‐linked ruthenium dye with functional cross‐linkers for dye‐sensitized solar cell
Authors: Liu Ken‐Yen , Ho Kuo‐Chuan , Lin King‐Fu 
Published: February 2013

ABSTRACTPhotovoltaic performance of cross‐linkable Ru(2,2′‐bipyridine‐4,4′‐bicarboxylic acid)(4,4′‐bis((4‐vinyl benzyloxy)methyl)‐2,2′‐bipyridine)(NCS)2 (denoted as RuS dye) adsorbing on TiO2 mesoporous film was enhanced by polymerizing with either ionic liquid monomer, 1‐(2‐acryloyloxy‐ethyl)‐3‐methyl‐imidazol‐1‐ium iodide (AMImI), to form RuS‐cross‐AMImI or di‐functional acrylic monomer with ether linkage, triethyleneglycodimethacrylate (TGDMA), to form RuS‐cross‐TGDMA. Their cross‐linking properties were investigated by UV–vis spectroscopy by rinsing with 0.1 N NaOH aqueous solution. The power conversion efficiencies (PCEs) of dye‐sensitized solar cells (DSSCs) with RuS‐cross‐AMImI and RuS‐cross‐TGDMA both reached over 8% under standard global air mass 1.5 full sunlight. The increased PCE for DSSCs with RuS‐cross‐AMImI comparing with cross‐linked RuS was attributed to the I− counterion of AMImI increasing the charge regeneration rate of RuS dye, whereas that with RuS‐cross‐TGDMA was attributed to the Li+ coordination property of TGDMA. The photovoltaic performance of RuS‐cross‐TGDMA was also slightly better than that of RuS‐cross‐AMImI because of higher open‐circuit photovoltage (Voc) and short‐circuit photocurrent (Jsc). Its higher Voc was supported by the Bode plot of impedance under illumination and Nyquist plots at dark, whereas higher Jsc was supported by the incident monochromatic photon‐to‐current conversion efficiency spectra and charge extraction experiments. Copyright © 2013 John Wiley & Sons, Ltd.
Study of Q224K, V152G double mutation in bean PGIP2, an LRR protein for plant defense—An in silico approach
Authors: Maulik Aditi , Basu Soumalee 
Published: February 2013

AbstractPolygalacturonase inhibiting proteins (PGIPs) are leucine‐rich repeat (LRR) proteins from plants that are organized into multigene families. They act as specific inhibitors against Polygalacturonases (PGs) from phytopathogens and share high sequence identity within species. We performed in silico mutation (Q224K and V152G) in PGIP2 from Phaseolus vulgaris to corresponding residues of another member, PGIP1. This mutation is known to cause 100% loss of inhibition against the PG of fungus Fusarium phyllophilum (Fp). A comparative analysis between PGIP2 and the double mutant, using 50 ns molecular dynamics simulations explored structural difference affecting PG binding properties. Simulations revealed that the mutation at 224, strains this residue which acts as a lock for the PGIP‐PG complex through main chain H‐bond. Changes in secondary structural elements and strain in the bend region along the convex face of the solenoidal protein affected the flexibility of the mutant protein. At the concave interacting face of the mutant, subtle changes in the sidechain behavior of the PG‐binding residues occurred in a concerted manner revealing flipping of aromatic rings to be crucial to avoid steric clash with FpPG in PGIP2. Docking PGIP2 and the mutant protein individually to FpPG illustrated the inability of the latter to inhibit FpPG leaving its active site free. Our study demonstrates that the effect of mutation affects the flexibility of the protein along the convex face, while binding specificity is altered through the concave face imparting minimal change in the typical structure supported by the LRRs. Proteins 2013. © 2012 Wiley Periodicals, Inc.
Nanoparticles exposing neurotensin tumor‐specific drivers
Authors: Falciani Chiara , Brunetti Jlenia , Lelli Barbara , Accardo Antonella , Tesauro Diego , Morelli Giancarlo , Bracci Luisa 
Published: February 2013

Nanoparticles have attracted much attention for their potential application as in vivo carriers of drugs. Labeling of nanoparticles with bioactive markers that are able to direct them toward specific biological target receptors has led to a new generation of drug delivery systems. In particular, low molecular weight peptides that remain stable in vivo could be promising tools to selectively drive nanoparticles loaded with active components to tumor cells.We reported, recently, that tetrabranched neurotensin peptides (NT4) may be used to selectively target tumor cells with liposomes. Liposomes functionalized with tetrabranched neurotensin peptide, NT4, and loaded with doxorubicin showed clear advantages in cell binding, anthracyclin internalization, and cytotoxicity in respect of not functionalized liposomes.In this study, we compare branched (NT4) versus linear (NT) peptides in the ability to drive liposomes to target cells and deliver their toxic cargo. We showed here that the more densely decorated liposomes had a better activity profile in terms of drug delivery. Presentation of peptides to the cell membranes in the grouped shape provided by branched structure facilitates liposome cell binding and fusion. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.
LuRh2Si2: Sensitivity of the Fermi surface to the Si z‐position
Authors: Reiss Pascal , Rourke Patrick M. C. , Zwicknagl Gertrud , Grosche F. Malte , Friedemann Sven 
Published: February 2013

AbstractWe present band structure calculations of the non‐magnetic compound LuRh2Si2 which serves as a reference for YbRh2Si2, a prototypical material for the investigation of quantum critical points. The relative z position of the Si atoms is found to have a strong impact on the band structure and the Fermi surface topology. We find the total energy to be minimized for z = 0.381c whereas a comparison of predicted extremal orbits with Shubnikov–de Haas frequencies shows best agreement at the experimental value z = 0.379c. We therefore recommend usage of z = 0.379c for future electronic structure calculations of LuRh2Si2 and YbRh2Si2.
Light‐induced degradation in copper‐contaminated gallium‐doped silicon
Authors: Lindroos Jeanette , Yli‐Koski Marko , Haarahiltunen Antti , Schubert Martin C. , Savin Hele 
Published: February 2013

AbstractTo date, gallium‐doped Czochralski (Cz) silicon has constituted a solar cell bulk material free of light‐induced degradation. However, we measure light‐induced degradation in gallium‐doped Cz silicon in the presence of copper impurities. The measured degradation depends on the copper concentration and the material resistivity. Gallium‐doped Cz silicon is found to be less sensitive to copper impurities than boron‐doped Cz silicon, emphasizing the role of boron in the formation of copper‐related light‐induced degradation. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Perceived Social Support in Spanish Cancer Outpatients with Psychiatric Disorder
Authors: Costa‐Requena Gema , Ballester Arnal Rafael , Gil Francisco 
Published: February 2013

AbstractThis study examines differences in perceived social support during oncology treatment of cancer patients, whilst taking into account the presence of psychiatric disorder. Of particular interest were cancer patients who received psychopharmacology treatment compared with those who did not. A total of 760 cancer outpatients were recruited from one hospital in Spain. Multivariate analysis of variance with the general linear model procedure was used. The Medical Outcomes Study Social Support Survey was used to assess social support perceived. The Diagnostic Interview Schedule using DSM‐III‐R criteria was utilized for the diagnosis of psychiatric disorders. There were significant differences between the patients diagnosed with a psychiatric disorder and those not diagnosed with psychiatric disorders in terms of perceived Emotional/Informational Support (F = 19.11, p < 0.01), Affectionate Support (F = 12.30, p < 0.01) and the Overall Support Index (F = 16.73, p < 0.01). In patients requiring psychopharmacology treatment, significant differences were presented with Structural Support (F = 4.32, p < 0.05), Emotional/Informational Support perceived (F = 7.87, p < 0.01), Instrumental Support (F = 4.17, p < 0.05) and Overall Support Index (F = 7.84, p < 0.01). Psychopharmacology treatment helped to increase the perception of social support received by the patient. Healthcare professionals could provide support that would normalize cancer patients' distress, taking into account the importance of perceived social support for the psychological well‐being of patients. Copyright © 2013 John Wiley & Sons, Ltd.
Distribution of P2O5 between Phosphorus‐Enrichment Phase and Matrix Phase in Phosphorus‐Containing Slag
Authors: Zhou Han‐Mei , Bao Yan‐Ping , Lin Lu 
Published: February 2013

AbstractIn order to make better recovery utilization of the phosphorus in the steel slag, and as P2O5 mainly exists in phosphorus‐enrichment phase and matrix phase of steel slag, it is a must to study the distribution of P2O5 between those two phases in the phosphorus‐containing slag and its related influencing factors. Heat experiments were conducted in this research, and the final slag was analyzed with the method of scanning electron microscope (SEM) + energy disperse spectroscopy (EDS). Then Lp, rp, and Cp in both phosphorus‐enrichment phase and matrix phase were calculated, respectively. From this study, is has been found that CaO% in matrix phase, the basicity of slag and mass fraction of P2O5 in both phosphorus‐enrichment phase and matrix phase influence the distribution ratio of P2O5 in the slag. Adding CaF2 also has effect on P2O5 partition while adding MgO and MnO has no obvious effect. Besides, for the low content of T.Fe in matrix phase, there is no linear relationship between Lp or $\gamma _{{\rm P}_{2} {\rm O}_{5} } $ and T.Fe in matrix phase.
Current Treatment and Outcome of Esophageal Perforations in Adults: Systematic Review and Meta‐Analysis of 75 Studies
Authors: Biancari Fausto , D’Andrea Vito , Paone Rosalba , Di Marco Carlo , Savino Grazia , Koivukangas Vesa , Saarnio Juha , Lucenteforte Ersilia 
Published: February 2013

AbstractBackgroundThe current prognosis of esophageal perforation and the efficacy of available treatment methods are not well defined.MethodsWe performed a systematic review of esophageal perforations published from January 2000 to April 2012 and subjected a proportion of the retrieved data to a meta‐analysis. Meta‐regression was performed to determine predictors of mortality immediately after esophageal perforation.ResultsAnalysis of 75 studies resulted in a pooled mortality of 11.9 % [95 % confidence interval (CI) 9.7–14.3: 75 studies with 2,971 patients] with a mean hospital stay of 32.9 days (95 % CI 16.9–48.9: 28 studies with 1,233 patients). Cervical perforations had a pooled mortality of 5.9 %, thoracic perforations 10.9 %, and intraabdominal perforations 13.2 %. Mortality after esophageal perforation secondary to foreign bodies was 2.1 %, iatrogenic perforation 13.2 %, and spontaneous perforation 14.8 %. Treatment started within 24 h after the event resulted in a mortality rate of 7.4 % compared with 20.3 % in patients treated later (risk ratio 2.279, 95 % CI 1.632–3.182). Primary repair was associated with a pooled mortality of 9.5 %, esophagectomy 13.8 %, T‐tube or any other tube repair 20.0 %, and stent‐grafting 7.3 %.ConclusionsResults of recent studies indicate that mortality after esophageal perforation is high despite any definitive surgical or conservative strategy. Stent‐grafting is associated with somewhat lower mortality rates, but studies may be biased by patient selection and limited experience.