bluuebunny/crossref_metadata_2025_split huggingface dataset:
Manganese‐Catalyzed Hydrogenation of Esters to Alcohols
Authors: Espinosa‐Jalapa Noel Angel , Nerush Alexander , Shimon Linda J. W. , Leitus Gregory , Avram Liat , Ben‐David Yehoshoa , Milstein David 
Published: October 2016

AbstractHomogeneous catalytic hydrogenation of esters to alcohols is an industrially important, environmentally benign reaction. While precious metal‐based catalysts for this reaction are now well known, only very few catalysts based on first‐row metal complexes were reported. Here we present the hydrogenation of esters catalyzed by a complex of earth‐abundant manganese. The reaction proceeds under mild conditions and insight into the mechanism is provided based on an NMR study and the synthesis of novel Mn complexes postulated as intermediates.
Periodic Mesoporous Organosilica with a Basic Urea‐Derived Framework for Enhanced Carbon Dioxide Capture and Conversion Under Mild Conditions
Authors: Liu Mengshuai , Lu Xingyuan , Shi Lei , Wang Fangxiao , Sun Jianmin 
Published: October 2016

AbstractA periodic mesoporous organosilica with a basic urea‐derived framework (PMO‐UDF) was prepared and characterized thoroughly. The PMO‐UDF showed an enhanced CO2 capture capacity at low pressure (≤1 atm) and an exceptional catalytic activity in CO2 coupling reactions with various epoxides to yield the corresponding cyclic carbonates under mild conditions because of the presence of a high surface area, basic pyridine units, and multiple hydrogen‐bond donors. The highly stable catalyst could be reused at least six successive times without a significant decrease of the catalytic efficiency or structural deterioration, thus the PMO‐UDF composite is considered as a promising material for CO2 capture and conversion.
New Redox Polymers that Exhibit Reversible Cleavage of Sulfur Bonds as Cathode Materials
Authors: Baloch Marya , Ben Youcef Hicham , Li Chunmei , Garcia‐Calvo Oihane , Rodriguez Lide M. , Shanmukaraj Devaraj , Rojo Teofilo , Armand Michel 
Published: October 2016

AbstractTwo new cathode materials based on redox organosulfur polymers were synthesized and investigated for rechargeable lithium batteries as a proof‐of‐concept study. These cathodes offered good cycling performance owing to the absence of polysulfide solubility, which plagues Li/S systems. Herein, an aliphatic polyamine or a conjugated polyazomethine was used as the base to tether the redox‐active species. The activity comes from the cleavage and formation of S−S or N−S bonds, which is made possible by the rigid conjugated backbone. The synthesized polymers were characterized through FTIR spectroscopy and thermogravimetric analysis (TGA). Galvanostatic measurements were performed to evaluate the discharge/charge cycles and characterize the performance of the lithium‐based cells, which displayed initial discharge capacities of approximately 300 mA h g−1 at C/5 over 100 cycles with approximately 98 % Coulombic efficiency.
Degradation of lignin and cellulose during foliar litter decomposition in an alpine forest river
Authors: Yue Kai , Peng Changhui , Yang Wanqin , Peng Yan , Zhang Chuan , Huang Chunping , Wu Fuzhong 
Published: October 2016

AbstractLignin and cellulose are thought to be critical factors that affect the rate of litter decomposition; however, few data are available on their degradation dynamics during litter decomposition in lotic ecosystems, such as forest rivers, where litter can decompose much more rapidly than in terrestrial ecosystems. We studied the degradation of lignin and cellulose in the foliar litter of four dominant riparian species (willow:Salix paraplesia; azalea:Rhododendron lapponicum; cypress:Sabina saltuaria; and larch:Larix mastersiana) in an alpine forest river. Over an entire year's incubation, litter lignin and cellulose degraded by 14.7–100% and 57.7–100% of their initial masses, respectively, depending on litter species. Strong degradations of lignin and cellulose occurred in the prefreezing period (i.e., the first 41 d) during litter decomposition, and the degradation rate was the highest among all the decomposition periods regardless of litter species. Litter species, decomposition period, and environmental factors such as temperature and nutrient availability showed significant influences on lignin and cellulose degradation rates. Compared with previously reported data regarding the dynamics of lignin and cellulose during litter decomposition in terrestrial ecosystems, our results suggest that lignin and cellulose can be degraded much more rapidly in lotic ecosystems, indicating that the traditionally used two‐phased model for the dynamics of lignin in decomposing litter may not be suitable in lotic ecosystems.
An evaluation of inclusive capital stock for urban planning
Authors: Fujii Hidemichi , Managi Shunsuke 
Published: October 2016

Abstract
Rapid urbanization has caused significant problems, and sustainable city design can play an important role in solving these problems under limited budgets and resources. Previous studies have proposed city evaluation indicators that can suggest appropriate urban designs. However, these indicators do not clearly consider economic theory, which is crucial for understanding accumulation of urban capital stock by the flows from daily urban activities. This study proposes a research framework based on economic theory for evaluating urban sustainability; this framework uses the inclusive wealth index (IWI) concept to examine inclusive urban capital stock. It examines the advantages of using the IWI as a city evaluation indicator along with data envelopment analysis and a decomposition analysis framework. We use data for 20 Japanese ordinance‐designated cities for an empirical study to demonstrate a proposed approach for evaluating inclusive urban capital. The developed research application evaluates each city's relative superiority in terms of capital accumulation and identifies those factors determining changes in capital flows via changes in efficiency, priority, and scale. The combination of these results can be helpful to decision makers seeking to increase urban capital by considering reference city information and relative superiority.
White matter structural network abnormalities underlie executive dysfunction in amyotrophic lateral sclerosis
Authors: Dimond Dennis , Ishaque Abdullah , Chenji Sneha , Mah Dennell , Chen Zhang , Seres Peter , Beaulieu Christian , Kalra Sanjay 
Published: October 2016

AbstractResearch in amyotrophic lateral sclerosis (ALS) suggests that executive dysfunction, a prevalent cognitive feature of the disease, is associated with abnormal structural connectivity and white matter integrity. In this exploratory study, we investigated the white matter constructs of executive dysfunction, and attempted to detect structural abnormalities specific to cognitively impaired ALS patients. Eighteen ALS patients and 22 age and education matched healthy controls underwent magnetic resonance imaging on a 4.7 Tesla scanner and completed neuropsychometric testing. ALS patients were categorized into ALS cognitively impaired (ALSci, n = 9) and ALS cognitively competent (ALScc, n = 5) groups. Tract‐based spatial statistics and connectomics were used to compare white matter integrity and structural connectivity of ALSci and ALScc patients. Executive function performance was correlated with white matter FA and network metrics within the ALS group. Executive function performance in the ALS group correlated with global and local network properties, as well as FA, in regions throughout the brain, with a high predilection for the frontal lobe. ALSci patients displayed altered local connectivity and structural integrity in these same frontal regions that correlated with executive dysfunction. Our results suggest that executive dysfunction in ALS is related to frontal network disconnectivity, which potentially mediates domain‐specific, or generalized cognitive impairment, depending on the degree of global network disruption. Furthermore, reported co‐localization of decreased network connectivity and diminished white matter integrity suggests white matter pathology underlies this topological disruption. We conclude that executive dysfunction in ALSci is associated with frontal and global network disconnectivity, underlined by diminished white matter integrity. Hum Brain Mapp 38:1249–1268, 2017. © 2016 Wiley Periodicals, Inc.
Upregulation of endothelial gene markers in Wharton's jelly mesenchymal stem cells cultured on polyelectrolyte multilayers
Authors: Rammal Hassan , Harmouch Chaza , Maerten Clément , Gaucher Caroline , Boulmedais Fouzia , Schaaf Pierre , Voegel Jean Claude , Laurent‐Maquin Dominique , Menu Patrick , Kerdjoudj Halima 
Published: October 2016

AbstractDesigning convenient substrates is a pertinent parameter that can guide stem cell differentiation. Current research is directed toward differentiating mesenchymal stem cells (MSCs) into endothelial cells (ECs). It is generally accepted that MSCs cannot be easily differentiated into ECs without high concentrations of proangiogenic factors. To guide either bone marrow‐derived mesenchymal stem cells (BM‐MSCs) and Wharton's jelly‐derived mesenchymal stem cells (WJ‐MSCs) into ECs‐like phenotype, poly(allylamine‐hydrochloride)/poly(styrene‐sulfonate) multilayers film (PAH/PSS) was used as culture coating and compared to type I collagen (as control coating). After 2 weeks of culture and in absence of angiogenic growth factors, PAH/PSS upregulated KDR, PECAM‐1, and CDH5 genes, whereas combining PAH/PSS with endothelial growth media (EGM‐2®) led to the production of respective proteins by WJ‐MSCs. In contrast, not fully EC‐like phenotype is obtained from the differentiation of BM‐ or WJ‐MSCs cultured on type I collagen. Thus, using PAH/PSS coating in synergy with EGM‐2® appears as an ideal condition promoting WJ‐MSCs differentiation into ECs‐like. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 292–300, 2017.
Intravoxel incoherent motion (IVIM)‐derived parameters in diffusion‐weighted MRI: Associations with prognostic factors in invasive ductal carcinoma
Authors: Lee Youn Joo , Kim Sung Hun , Kang Bong Joo , Kang Young Jee , Yoo Heesoo , Yoo Jaewan , Lee Jaeun , Son Yo Han , Grimm Robert 
Published: October 2016

PurposeTo investigate relationships between intravoxel incoherent motion (IVIM) metrics of invasive ductal carcinoma of the breast and prognostic factors.Materials and MethodsThis retrospective study included a total of 82 masses from 72 patients who underwent 3T breast magnetic resonance imaging (MRI) and diffusion‐weighted imaging. IVIM metrics of tissue diffusivity (Dslow), pseudodiffusivity (Dfast), and perfusion fraction (Dpf) were measured using histogram analysis for whole lesion volumes. We evaluated relationships between IVIM metrics and prognostic factors or subtypes of invasive ductal carcinoma.ResultsThe Dslow 50th, 75th, and 90th percentile metrics were reduced in the estrogen receptor (ER)‐positive group compared with the ER‐negative group (individually, P = 0.044, 0.024, 0.045). Additionally, the Dslow 75th percentile value was a significant differentiator of histologic grade, tumor subtype, and Ki‐67 grouping (individually, P = 0.024, 0.049, 0.016). The Dpf mean, 75th, 90th percentile, skewness, and kurtosis metrics were correlated with the size of ductal carcinoma in situ (DCIS) component (individually, P = 0.034, 0.032, 0.027, 0.013, 0.013).ConclusionThe Dslow metrics differentiated between ER‐positive and ‐negative groups, and the Dpf metrics were associated with the size of the DCIS component.Level of Evidence: 4J. MAGN. RESON. IMAGING 2017;45:1394–1406
PET/MRI of metabolic activity in osteoarthritis: A feasibility study
Authors: Kogan Feliks , Fan Audrey P. , McWalter Emily J. , Oei Edwin H. G. , Quon Andrew , Gold Garry E. 
Published: October 2016

PurposeTo evaluate positron emission tomography / magnetic resonance imaging (PET/MRI) knee imaging to detect and characterize osseous metabolic abnormalities and correlate PET radiotracer uptake with osseous abnormalities and cartilage degeneration observed on MRI.Materials and MethodsBoth knees of 22 subjects with knee pain or injury were scanned at one timepoint, without gadolinium, on a hybrid 3.0T PET‐MRI system following injection of 18F‐fluoride or 18F‐fluorodeoxyglucose (FDG). A musculoskeletal radiologist identified volumes of interest (VOIs) around bone abnormalities on MR images and scored bone marrow lesions (BMLs) and osteophytes using a MOAKS scoring system. Cartilage appearance adjacent to bone abnormalities was graded with MRI‐modified Outerbridge classifications. On PET standardized uptake values (SUV) maps, VOIs with SUV greater than 5 times the SUV in normal‐appearing bone were identified as high‐uptake VOI (VOIHigh). Differences in 18F‐fluoride uptake between bone abnormalities, BML, and osteophyte grades and adjacent cartilage grades on MRI were identified using Mann–Whitney U‐tests.ResultsSUVmax in all subchondral bone lesions (BML, osteophytes, sclerosis) was significantly higher than that of normal‐appearing bone on MRI (P < 0.001 for all). Of the 172 high‐uptake regions on 18F‐fluoride PET, 63 (37%) corresponded to normal‐appearing subchondral bone on MRI. Furthermore, many small grade 1 osteophytes (40 of 82 [49%]), often described as the earliest signs of osteoarthritis (OA), did not show high uptake. Lastly, PET SUVmax in subchondral bone adjacent to grade 0 cartilage was significantly lower compared to that of grades 1–2 (P < 0.05) and grades 3–4 cartilage (P < 0.001).ConclusionPET/MRI can simultaneously assess multiple early metabolic and morphologic markers of knee OA across multiple tissues in the joint. Our findings suggest that PET/MR may detect metabolic abnormalities in subchondral bone, which appear normal on MRI.Level of Evidence: 2Technical Efficacy: Stage 1J. MAGN. RESON. IMAGING 2017;45:1736–1745
Positive Group Affective Tone and Team Creative Performance and Change‐Oriented Organizational Citizenship Behavior: A Moderated Mediation Model
Authors: Shin Yuhyung , Kim Mihee , Lee Sang‐Hoon 
Published: October 2016

AbstractDespite the vast amount of research on creativity and organizational citizenship behavior (OCB), little knowledge has been accumulated with respect to underlying mechanisms and boundary conditions affecting team creative performance and change OCB. To fill this research gap, this study aims at proposing and testing a moderated mediation model that delineates the relationships among positive group affective tone (PGAT), team reflexivity, team leader transformational leadership, team creative performance, and team change OCB. As hypothesized, PGAT was positively associated with team reflexivity, which in turn significantly predicted team creative performance and change OCB. In addition, the relationship between PGAT and team reflexivity and the indirect effects of PGAT on team creative performance and change OCB through team reflexivity were more pronounced when team leader transformational leadership was high than when it was low. These findings were validated in a post hoc analysis that compared the proposed moderated mediation model with alternative models.
Correction of phase errors in quantitative water–fat imaging using a monopolar time‐interleaved multi‐echo gradient echo sequence
Authors: Ruschke Stefan , Eggers Holger , Kooijman Hendrik , Diefenbach Maximilian N. , Baum Thomas , Haase Axel , Rummeny Ernst J. , Hu Houchun H. , Karampinos Dimitrios C. 
Published: October 2016

PurposeTo propose a phase error correction scheme for monopolar time‐interleaved multi‐echo gradient echo water–fat imaging that allows accurate and robust complex‐based quantification of the proton density fat fraction (PDFF).MethodsA three‐step phase correction scheme is proposed to address a) a phase term induced by echo misalignments that can be measured with a reference scan using reversed readout polarity, b) a phase term induced by the concomitant gradient field that can be predicted from the gradient waveforms, and c) a phase offset between time‐interleaved echo trains. Simulations were carried out to characterize the concomitant gradient field‐induced PDFF bias and the performance estimating the phase offset between time‐interleaved echo trains. Phantom experiments and in vivo liver and thigh imaging were performed to study the relevance of each of the three phase correction steps on PDFF accuracy and robustness.ResultsThe simulation, phantom, and in vivo results showed in agreement with the theory an echo time‐dependent PDFF bias introduced by the three phase error sources. The proposed phase correction scheme was found to provide accurate PDFF estimation independent of the employed echo time combination.ConclusionComplex‐based time‐interleaved water–fat imaging was found to give accurate and robust PDFF measurements after applying the proposed phase error correction scheme. Magn Reson Med 78:984–996, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
Diffusion‐weighted J‐resolved spectroscopy
Authors: Landheer Karl , Schulte Rolf , Geraghty Ben , Hanstock Christopher , Chen Albert P. , Cunningham Charles H. , Graham Simon J. 
Published: October 2016

PurposeTo develop a novel diffusion‐weighted magnetic resonance spectroscopy (DW‐MRS) technique in conjunction with J‐resolved spatially localized spectroscopy (JPRESS) to measure the apparent diffusion coefficients (ADCs) of brain metabolites beyond N‐acetylaspartic acid (NAA), creatine (Cr), and choline (Cho) at 3T. This technique will be useful to probe tissue microstructures in vivo, as the various metabolites have different physiological characteristics.MethodsTwo JPRESS spectra were collected (high b‐value and low b‐value), and the ADCs of 16 different metabolites were estimated. Two analysis pipelines were developed: 1) a 2D pipeline that uses ProFit software to extract ADCs from metabolites not typically accessible at 3T and 2) a 1D pipeline that uses TARQUIN software to extract the metabolite concentrations from each line in the 2D dataset, allowing for scaling as well as validation.ResultsThe ADCs of 16 different metabolites were estimated from within six subjects in parietal white matter. There was excellent agreement between the results obtained from the 1D and 2D pipelines for NAA, Cr, and Cho.ConclusionThe proposed technique provided consistent estimates for the ADCs of NAA, Cr, Cho, glutamate + glutamine, and myo‐inositol in all subjects and additionally glutathione and scyllo‐inositol in all but one subject. Magn Reson Med 78:1235–1245, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
Quantitative measurement of cerebral blood volume using velocity‐selective pulse trains
Authors: Liu Dexiang , Xu Feng , Lin Doris D. , van Zijl Peter C.M. , Qin Qin 
Published: October 2016

PurposeTo develop a non–contrast‐enhanced MRI method for cerebral blood volume (CBV) mapping using velocity‐selective (VS) pulse trains.MethodsThe new pulse sequence applied velocity‐sensitive gradient waveforms in the VS label modules and velocity‐compensated ones in the control scans. Sensitivities to the gradient imperfections (e.g., eddy currents) were evaluated through phantom studies. CBV quantification procedures based on simulated labeling efficiencies for arteriolar, capillary, and venular blood as a function of cutoff velocity (Vc) are presented. Experiments were conducted on healthy volunteers at 3T to examine the effects of unbalanced diffusion weighting, cerebrospinal (CSF) contamination and variation of Vc.ResultsPhantom results of the used VS pulse trains demonstrated robustness to eddy currents. The mean CBV values of gray matter and white matter for the experiments using Vc = 3.5 mm/s and velocity‐compensated control with CSF‐nulling were 5.1 ± 0.6 mL/100 g and 2.4 ± 0.2 mL/100 g, respectively, which were 23% and 32% lower than results from the experiment with velocity‐insensitive control, corresponding to 29% and 25% lower in averaged temporal signal‐to‐noise ratio values.ConclusionA novel technique using VS pulse trains was demonstrated for CBV mapping. The results were both qualitatively and quantitatively close to those from existing methods. Magn Reson Med 77:92–101, 2017. © 2016 International Society for Magnetic Resonance in Medicine
Increased robustness in reference region model analysis of DCE MRI using two‐step constrained approaches
Authors: Ahmed Zaki , Levesque Ives R. 
Published: October 2016

PurposeReference region models (RRMs) can quantify tumor perfusion in dynamic contrast‐enhanced MRI without an arterial input function. Inspection of the RRM reveals that one of the free parameters in the fit is uniquely linked to the reference region and is common to all voxels. A two‐step approach is proposed that takes this constraint into account.MethodsThree constrained RRM (CRRM) approaches were devised and evaluated. Simulations were performed to compare their accuracy and precision over a range of noise and temporal resolutions. The CRRM was also applied on a virtual phantom that simulates different perfusion values. In vivo evaluation was performed on data from breast cancer and soft tissue sarcoma.ResultsIn simulations, the CRRM consistently improved precision and had better accuracy at low signal‐to‐noise ratio (SNR). In virtual phantom, the CRRMs were able to fit voxels that had similar kinetics to the reference tissue, whereas the unconstrained models failed to accurately fit these voxels. In the in vivo data, the constrained approaches produced parameter maps that had less variability and were in better agreement with the Tofts model.ConclusionThese findings indicate that the two‐step fitting approach of the CRRM can reduce the variability of perfusion estimates for quantifying perfusion with dynamic contrast‐enhanced (DCE) MRI. Magn Reson Med 78:1547–1557, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
Local SAR near deep brain stimulation (DBS) electrodes at 64 and 127 MHz: A simulation study of the effect of extracranial loops
Authors: Golestanirad Laleh , Angelone Leonardo M. , Iacono Maria Ida , Katnani Husam , Wald Lawrence L. , Bonmassar Giorgio 
Published: October 2016

PurposeMRI may cause brain tissue around deep brain stimulation (DBS) electrodes to become excessively hot, causing lesions. The presence of extracranial loops in the DBS lead trajectory has been shown to affect the specific absorption rate (SAR) of the radiofrequency energy at the electrode tip, but experimental studies have reported controversial results. The goal of this study was to perform a systematic numerical study to provide a better understanding of the effects of extracranial loops in DBS leads on the local SAR during MRI at 64 and 127 MHz.MethodsA total of 160 numerical simulations were performed on patient‐derived data, in which relevant factors including lead length and trajectory, loop location and topology, and frequency of MRI radiofrequency (RF) transmitter were assessed.ResultsOverall, the presence of extracranial loops reduced the local SAR in the tissue around the DBS tip compared with straight trajectories with the same length. SAR reduction was significantly larger at 127 MHz compared with 64 MHz. SAR reduction was significantly more sensitive to variable loop parameters (eg, topology and location) at 127 MHz compared with 64 MHz.ConclusionLead management strategies could exist that significantly reduce the risks of 3 Tesla (T) MRI for DBS patients. Magn Reson Med 78:1558–1565, 2017. © 2016 International Society for Magnetic Resonance in Medicine.