bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dinuclear Zinc and Cobalt Complexes with Imidazolyl and N‐Methylmidazolyl Units and Their Solution Speciation and Redox Properties
Authors: Kügler Merle , Gałęzowska Joanna , Schendzielorz Florian , Dechert Sebastian , Demeshko Serhiy , Siewert Inke 
Published: May 2015

AbstractHerein, we report the synthesis of a new ligand, which is preorganised for the complexation of two metal ions and has two 1H‐imidazolyl units in the outer ligand sphere. The zinc and cobalt complexes with the ligand were synthesised and fully characterised, and their solid‐state structures were determined. The complexes show a highly symmetric [M2L2]2+ structural motif. The thermodynamic data, that is, the overall stability constants and redox potential of the Co2+/Co3+ couple, were determined. Potentiometric studies revealed the presence of mononuclear (below pH 7) and differently protonated dimeric species (above pH 7). The formation of distinct species was corroborated by ESI‐MS measurements. Similar species were obtained for the corresponding zinc complexes. Additionally, we determined the dependence of the Co2+/Co3+ redox couple on the protonation state of the complex. The studies showed that there is a considerably strong thermodynamic coupling between the NH protons of the imidazolyl units and the oxidation state of the metal ion. Upon deprotonation of all four NH units, the potential of the redox couple shifted by ca. 1.1 V. We also synthesised the analogous ligand with N‐methylimidazolyl units to investigate the influence of the NH protons on the properties of the complexes. The methylation of the NH unit has virtually no influence on the redox, magnetic and structural properties of the zinc and cobalt complexes.
The Thia‐Michael Reactivity of Zerumbone and Related Cross‐Conjugated Dienones: Disentangling Stoichiometry, Regiochemistry, and Addition Mode with an NMR‐Spectroscopy‐Based Cysteamine Assay
Authors: Appendino Giovanni , Minassi Alberto , Collado Juan A. , Pollastro Federica , Chianese Giuseppina , Taglialatela‐Scafati Orazio , Ayyari Mehdi , Garcia Victor , Muñoz Eduardo 
Published: May 2015

AbstractThe cross‐conjugated and electrophilic dienone system of the humulane sesquiterpene zerumbone (1a) was modified by E/Z photochemical isomerization and/or by removal of homoconjugation with the isolated endocyclic double bond of the medium‐sized ring. The site (C‐6/C‐9), mode (transient or irreversible), stoichiometry (single or twofold), and comparative rates of thiol addition were evaluated using an NMR‐spectroscopy‐based cysteamine assay. Dramatic effects were seen, and this highlights the subtleties of the reaction and the limitations of our predictive power in this field. For biological endpoints sensitive to thiol trapping, a substantial separation between Michael reactivity and biological activity was found for 1a and its analogues. This supports the view that shape complementarity plays a critical role in the covalent binding of Michael acceptors to their macromolecular target(s).
[3+2] Route to Quaternary Oxaprolinol Derivatives as Masked Precursors of Disubstituted β3,β3‐Amino Aldehyde
Authors: Shpak‐Kraievskyi Pavlo , Mankou Makaya Amelle , Beauchard Anne , Martel Arnaud , Laurent Mathieu Y. , Dujardin Gilles 
Published: May 2015

AbstractBicyclic isoxazolidines displaying one or two quaternary stereocenter(s) were formed starting from functional cyclic ketonitrones equipped with a phenyl glycinol chiral auxiliary. The products were engaged in stereocontrolled 1,3‐dipolar cycloaddition reactions with a range of electron‐rich and electron‐poor dipolarophiles. A new reductive removal of the phenyl glycinol chiral auxiliary was introduced and was shown to afford chemoselectively a quaternary isoxazolidine derivative (of oxaprolinol‐type) without cleaving the N–O isoxazolidine bond. Keeping the aldehyde function masked as a cyclic pseudo‐acetal, the liberated oxy‐amine function was shown to be available for a pseudo‐peptide coupling with various N‐protected amino acids. The isoxazolidine ring was opened by a reductive N–O bond cleavage, giving a pseudo‐dipeptide that was C‐terminated with an aldehyde function.
Maximum likelihood estimation of the multivariate hidden dynamic geostatistical model with application to air quality in Apulia, Italy
Authors: Calculli Crescenza , Fassò Alessandro , Finazzi Francesco , Pollice Alessio , Turnone Annarita 
Published: May 2015

Multivariate spatio‐temporal statistical models are deserving for increasing attention for environmental data in general and for air quality data in particular because they can reveal dependencies and spatio‐temporal dynamics across multiple variables and can be used to obtain dynamic concentration maps over specified areas.In this frame, we introduce a multivariate generalization of a known spatio‐temporal model referred to as the hidden dynamic geostatistical model. Maximum likelihood parameter estimates are obtained implementing the expectation maximization algorithm and suitably extending the D‐STEM software, recently introduced for alternative model specifications, allowing to handle multiple variables with heterogeneous spatial support, covariates, and missing data.A case study illustrates some of the statistical issues typical of a medium complexity problem related to air quality data modeling. Considering air quality and meteorological data over the Apulia region, Italy, the usual approach using meteorological variables as regressors is not possible because these data are observed on different monitoring networks, and preliminary spatial interpolation to co‐locate the data is to be avoided. Hence, an eight‐variate model is considered for understanding the relations between daily concentrations of particulate matters (PM10) and nitrogen dioxides (NO2) and six non co‐located meteorological variables. Model interpretation is given, and its use for dynamic map construction, uncertainty included, is illustrated. Moreover, some preliminary evidence of the model capability to detect a Saharan dust event is presented. Copyright © 2015 John Wiley & Sons, Ltd.
Choroid plexus separation in fetuses without ventriculomegaly: Natural course and postnatal outcome
Authors: Ipek Ali , Tanrivermis Sayit Asli , Idilman Ilkay S. , Kurt Aydın , Cay Nurdan , Unal Ozlem , Karabulut Erdem , Keskin Huseyin Levent , Karaoglanoglu Mustafa 
Published: May 2015

ABSTRACTPurposeTo evaluate fetuses with choroid plexus separation without ventriculomegaly in terms of fetal malformations, behavior of the separation during follow‐up, and postnatal outcome.MethodsIn total, 172 fetuses with choroid plexus separation without ventriculomegaly were included in this prospective study. Fetal sonography was performed at 2‐ to 4‐week intervals, and detailed physical and neurologic examinations were performed after their delivery. Fetuses were categorized into normal and abnormal subgroups according to the outcome.ResultsSixteen fetuses (9.3%) were included in the abnormal‐outcome group and 156 fetuses (90.7%) were included in the normal‐outcome group. Both the initial mean lateral ventricular diameter (9.3 mm versus 8.6 mm) and the initial mean choroid plexus separation (4.8 mm versus 3.3 mm) were greater in the abnormal group than in the normal group (p < 0.001 for both comparisons). We found that 4.0 mm was the best cutoff point of choroid plexus separation to detect a major anomaly, with 87.5% sensitivity and 93.6% specificity.ConclusionsChoroid plexus separation without ventriculomegaly often resolves within the third trimester and does not affect postnatal outcome. It can be associated with various fetal malformations; however, with a comprehensive examination, all fetal malformations can be detected prenatally. Follow‐up sonography studies would be useful, especially in the case of suspected corpus callosum agenesis. © 2015 Wiley Periodicals, Inc. J Clin Ultrasound 43:478–484 2015
Vasa expression in spermatogenic cells during the reproductive‐cycle phases of Podarcis sicula (Reptilia, Lacertidae)
Authors: Milani Liliana , Maurizii Maria Gabriella 
Published: May 2015

ABSTRACTThe vasa gene encodes a DEAD‐box ATP‐dependent RNA helicase that regulates the translation of multiple mRNAs involved in germ line differentiation. This protein has been deeply studied in many animals, but few data are available to date on reptiles. In this work, we sequenced a portion of Podarcis sicula vasa gene (Ps‐vasa), developed a specific antibody and verified its specificity. Using anti‐Ps‐Vasa and confocal microscopy, we studied Vasa expression in male germ cells during the reproductive cycle of P. sicula: during full gonadal activity (spring), during regression of gonadal activity (summer) and during slow autumnal recrudescence. We also analyzed Vasa expression in young testes when the walls of the seminiferous tubules were forming. The aim was to verify if Vasa is involved in the process of male germ cell differentiation in all phases of the reproductive cycle. In adult testes, during full gonadal activity and during recrudescence, Vasa staining was detected from spermatogonia to spermatids. Vasa spots were also observed in the nucleus of germ cells supporting its function in different cellular compartments. No Vasa staining was observed in mature spermatozoa during the spring and mid‐late November. The seminiferous epithelium analyzed in the summer appeared reduced with only spermatogonia, all Vasa‐immunostained, some in division to replace germ cells. In immature testes, the seminiferous epithelium contained only spermatogonia and spermatocytes. The clear immunostaining in their cytoplasm revealed that Vasa is already expressed in juvenile male gonads, suggesting a role in the differentiation process since P. sicula early developmental stages. J. Exp. Zool. (Mol. Dev. Evol.) 324B: 424–434, 2015. © 2015 Wiley Periodicals, Inc.
Obese patients and radiography literature: what do we know about a big issue?
Authors: Le Nhat Tan Thanh , Robinson John , Lewis Sarah J. 
Published: May 2015

AbstractObesity is a global health issue with obese patients requiring specialised diagnosis, treatment and care through the health service. The practical and social difficulties associated with medical imaging of obese patients are an increasingly common problem and it is currently unknown how student and qualified radiographers perceive and respond to these challenges. By better understanding challenges presented in providing quality imaging and care of imaging obese patients, education for both qualified and student radiographers can be enhanced. Radiographers are heavily reliant on visual and tactile senses to locate the position of anatomical structures for diagnostic imaging and determine radiation exposure through a delicate consideration of dose, image quality and anatomical attenuation. However, obese patients require modifications to routine radiographic practice in terms of movement/assisted positioning, equipment capabilities to take increased weight or coverage. These patients may also be subject to compromised radiological diagnosis through poor visualisation of structures. In this paper, the professional and educational literature was narratively reviewed to assess gaps in the evidence base related to the skill and care knowledge for obese patients. Literature was sourced relating to discrete radiographic considerations such as the technical factors of imaging obese patients, exposure and the impact of obesity on imaging departments’ service provisions. The recent literature (post‐2000 to coincide with the sharp increase in global obesity) on the perceptions of health professionals and student health practitioners has also been explored because there are no specific radiographer studies to report. By understanding the research in similar fields, we may identify what common attitudes qualified and student radiographer's hold and what challenges, technical and care related, can be prepared for.
An interface‐enriched generalized finite element analysis for electromagnetic problems with non‐conformal discretizations
Authors: Zhang Kedi , Najafi Ahmad Raeisi , Jin Jian‐Ming , Geubelle Philippe H. 
Published: May 2015

SummaryAn interface‐enriched generalized finite element method is presented for analyzing electromagnetic problems involving highly inhomogeneous materials. To avoid creating conformal meshes within a complex computational domain and preparing multiple meshes during optimization, enriched vector basis functions are introduced over the finite elements that intersect the material interfaces to capture the normal derivative discontinuity of the tangential field component. These enrichment functions are directly constructed from a linear combination of the vector basis functions of the sub‐elements. Several numerical examples are presented to verify the method with analytical solutions and demonstrate its h‐refinement convergence rate. The proposed interface‐enriched generalized finite element method is shown to achieve the same level of accuracy as the standard finite element method based on conformal meshes. Two examples, involving multiple microvascular channels and circular inclusions of different radii, are analyzed to illustrate the capability of the proposed approach in handling complicated inhomogeneous geometries. Copyright © 2015 John Wiley & Sons, Ltd.
Phosphorylation of myofibrillar proteins in post‐mortem ovine muscle with different tenderness
Authors: Chen Lijuan , Li Xin , Ni Na , Liu Yue , Chen Li , Wang Zhenyu , Shen Qingwu W , Zhang Dequan 
Published: May 2015

AbstractBACKGROUNDTenderness is one of the most important quality attributes especially for beef and lamb. As protein phosphorylation and dephosphorylation regulate glycolysis, muscle contraction and turnover of proteins within living cells, it may contribute to the conversion of muscle to meat. The changes of myofibrillar protein phosphorylation in post‐mortem ovine muscle with different levels of tenderness were investigated in this study.RESULTSThe protein phosphorylation level (P/T ratio) of the tender group increased from 0.5 to 12 h post mortem and then decreased. The P/T ratio of tough group increased during 24 h post mortem, increasing faster from 0.5 to 4 h post mortem than from 4 to 24 h post mortem.The global phosphorylation level of tough meat was significantly higher than tender meat at 4, 12 and 24 h post mortem (P < 0.05). Protein identification revealed that most of the phosphoproteins were proteins with sarcomeric function; the others were involved in glycometabolism, stress response, etc. The phosphorylation levels of myofibrillar proteins, e.g. myosin light chain 2 and actin, were significantly different among groups of different tenderness and at different post‐mortem time points (P < 0.05).CONCLUSIONProtein phosphorylation may influence meat rigor mortis through contractile machinery and glycolysis, which in turn affect meat tenderness. © 2015 Society of Chemical Industry
Single injection of basic fibroblast growth factor to treat severe vocal fold lesions and vocal fold paralysis
Authors: Kanazawa Takeharu , Komazawa Daigo , Indo Kanako , Akagi Yusuke , Lee Yogaku , Nakamura Kazuhiro , Matsushima Koji , Kunieda Chikako , Misawa Kiyoshi , Nishino Hiroshi , Watanabe Yusuke 
Published: May 2015

Objectives/HypothesisSevere vocal fold lesions such as vocal fold sulcus, scars, and atrophy induce a communication disorder due to severe hoarseness, but a treatment has not been established. Basic fibroblast growth factor (bFGF) therapies by either four‐time repeated local injections or regenerative surgery for vocal fold scar and sulcus have previously been reported, and favorable outcomes have been observed. In this study, we modified bFGF therapy using a single of bFGF injection, which may potentially be used in office procedures.Study DesignRetrospective chart review.MethodsFive cases of vocal fold sulcus, six cases of scars, seven cases of paralysis, and 17 cases of atrophy were treated by a local injection of bFGF. The injection regimen involved injecting 50 µg of bFGF dissolved in 0.5 mL saline only once into the superficial lamina propria using a 23‐gauge injection needle. Two months to 3 months after the injection, phonological outcomes were evaluated.ResultsThe maximum phonation time (MPT), mean airflow rate, pitch range, speech fundamental frequency, jitter, and voice handicap index improved significantly after the bFGF injection. Furthermore, improvement in the MPT was significantly greater in patients with (in increasing order) vocal fold atrophy, scar, and paralysis. The improvement in the MPT among all patients was significantly correlated with age; the MPT improved more greatly in younger patients.ConclusionsRegenerative treatments by bFGF injection—even a single injection—effectively improve vocal function in vocal fold lesions.Level of Evidence4 Laryngoscope, 125:E338–E344, 2015
A Taxonomy of Social Networking Site Users: Social Surveillance and Self‐surveillance Perspective
Authors: Park Min‐Sook , Shin Jong‐Kuk , Ju Yong 
Published: May 2015

ABSTRACTSince social networking sites (SNS) are widely used in modern society, users increasingly use SNS to manage or maintain their existing social relationships and form new ones. This research applies social surveillance and self‐surveillance to classify SNS user types and explores each type's effect on SNS’ marketing performances. Three hundred three online questionnaires are collected to test the research questions. The results of cluster analysis and multivariate analysis of variance (MANOVA) reveal the following four user types based on the different degrees of social surveillance and self‐surveillance:versatile users,self‐expression users,pass‐along users, andintrovert users. Further, the introvert users have the least impact on product‐related information sharing, perception of social presence, purchase intention toward offers on SNS, and emotional experiences in social shopping among the four SNS user types.
P‐LORAKS: Low‐rank modeling of local k‐space neighborhoods with parallel imaging data
Authors: Haldar Justin P. , Zhuo Jingwei 
Published: May 2015

PurposeTo propose and evaluate P‐LORAKS a new calibrationless parallel imaging reconstruction framework.Theory and MethodsLORAKS is a flexible and powerful framework that was recently proposed for constrained MRI reconstruction. LORAKS was based on the observation that certain matrices constructed from fully sampled k‐space data should have low rank whenever the image has limited support or smooth phase, and made it possible to accurately reconstruct images from undersampled or noisy data using low‐rank regularization. This paper introduces P‐LORAKS, which extends LORAKS to the context of parallel imaging. This is achieved by combining the LORAKS matrices from different channels to yield a larger but more parsimonious low‐rank matrix model of parallel imaging data. This new model can be used to regularize the reconstruction of undersampled parallel imaging data, and implicitly imposes phase, support, and parallel imaging constraints without needing to calibrate phase, support, or sensitivity profiles.ResultsThe capabilities of P‐LORAKS are evaluated with retrospectively undersampled data and compared against existing parallel MRI reconstruction methods. Results show that P‐LORAKS can improve parallel imaging reconstruction quality, and can enable the use of new k‐space trajectories that are not compatible with existing reconstruction methods.ConclusionThe P‐LORAKS framewok provides a new and effective way to regularize parallel imaging reconstruction. Magn Reson Med 75:1499–1514, 2016. © 2015 Wiley Periodicals, Inc.
Utilization of a balanced steady state free precession signal model for improved fat/water decomposition
Authors: Henze Bancroft Leah C. , Strigel Roberta M. , Hernando Diego , Johnson Kevin M. , Kelcz Frederick , Kijowski Richard , Block Walter F. 
Published: May 2015

PurposeChemical shift based fat/water decomposition methods such as IDEAL are frequently used in challenging imaging environments with large B0 inhomogeneity. However, they do not account for the signal modulations introduced by a balanced steady state free precession (bSSFP) acquisition. Here we demonstrate improved performance when the bSSFP frequency response is properly incorporated into the multipeak spectral fat model used in the decomposition process.Theory and MethodsBalanced SSFP allows for rapid imaging but also introduces a characteristic frequency response featuring periodic nulls and pass bands. Fat spectral components in adjacent pass bands will experience bulk phase offsets and magnitude modulations that change the expected constructive and destructive interference between the fat spectral components. A bSSFP signal model was incorporated into the fat/water decomposition process and used to generate images of a fat phantom, and bilateral breast and knee images in four normal volunteers at 1.5 Tesla.ResultsIncorporation of the bSSFP signal model into the decomposition process improved the performance of the fat/water decomposition.ConclusionIncorporation of this model allows rapid bSSFP imaging sequences to use robust fat/water decomposition methods such as IDEAL. While only one set of imaging parameters were presented, the method is compatible with any field strength or repetition time. Magn Reson Med 75:1269–1277, 2016. © 2015 Wiley Periodicals, Inc.
MAGPI: A framework for maximum likelihood MR phase imaging using multiple receive coils
Authors: Dagher Joseph , Nael Kambiz 
Published: May 2015

PurposeCombining MR phase images from multiple receive coils is a challenging problem, complicated by ambiguities introduced by phase wrapping, noise, and the unknown phase‐offset between the coils. Various techniques have been proposed to mitigate the effect of these ambiguities but most of the existing methods require additional reference scans and/or use ad hoc post‐processing techniques that do not guarantee any optimality.Theory and MethodsHere, the phase estimation problem is formulated rigorously using a maximum‐likelihood (ML) approach. The proposed framework jointly designs the acquisition‐processing chain: the optimized pulse sequence is a single multiecho gradient echo scan and the corresponding postprocessing algorithm is a voxel‐per‐voxel ML estimator of the underlying tissue phase.ResultsOur proposed framework (Maximum AmbiGuity distance for Phase Imaging, MAGPI) achieves substantial improvements in the phase estimate, resulting in phase signal‐to‐noise ratio (SNR) gains by up to an order of magnitude compared to existing methods.ConclusionThe advantages of MAGPI are: (1) ML‐optimal combination of phase data from multiple receive coils, without a reference scan; (2) voxel‐per‐voxel ML‐optimal estimation of the underlying tissue phase, without the need for phase unwrapping or image smoothing; and (3) robust dynamic estimation of channel‐dependent phase‐offsets. Magn Reson Med 75:1218–1231, 2016. © 2015 Wiley Periodicals, Inc.
A return mapping algorithm for unified strength theory model
Authors: Lin Chen , Li Yue‐Ming 
Published: May 2015

SummaryA return mapping algorithm in principal stress space for unified strength theory (UST) model is presented in this paper. In contrast to Mohr–Coulomb and Tresca models, UST model contains two planes and three corners in the sextant of principal stress space, and the apex is formed by the intersection of 12 corners rather than the six corners of Mohr–Coulomb in the whole principal stress space. In order to utilize UST model, the existing return mapping algorithm in principal stress space is modified. The return mapping schemes for one plane, middle corner, and apex of UST model are derived, and corresponding consistent constitutive matrices in principal stress space are constructed. Because of the flexibility of UST, the present model is not only suitable for analysis based on the traditional yield functions, such as Mohr–Coulomb, Tresca, and Mises, but might also be used for analysis based on a series of new failure criteria. The accuracy of the present model is assessed by the iso‐error maps. Three numerical examples are also given to demonstrate the capability of the present algorithm. Copyright © 2015 John Wiley & Sons, Ltd.