bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cardiac motion and spillover correction for quantitative PET imaging using dynamic MRI
Authors: Marchesseau Stephanie , Totman John J. , Fadil Hakim , Leek Francesca A. A. , Chaal Jasper , Richards Mark , Chan Mark , Reilhac Anthonin 
Published: December 2018

PurposeCardiac positron emission tomography/magnetic resonance imaging (PET/MRI) acquisition presents novel clinical applications thanks to the combination of viability and metabolic imaging (PET) and functional and structural imaging (MRI). However, the resolution of PET, as well as cardiac and respiratory motion in nongated cardiac imaging acquisition protocols, leads to a reduction in image quality and severe quantitative bias. Respiratory or cardiac motion is customarily addressed with gated reconstruction which results in higher noise.MethodsInspired by a method that has been used in brain PET, a practical correction approach, designed to overcome these existing limitations for quantitative PET imaging, was developed and applied in the context of cardiac PET/MRI. The correction approach for PET data consists of computing the mean density map of each underlying moving region, as obtained with MRI, and translating them to the PET space taking into account the PET spatial and temporal resolution. Using these tissue density maps, the method then constructs a system of linear equations that models the activity recovery and cross‐contamination coefficients, which can be solved for the true activity values. Physical and numerical cardiac phantoms were employed in order to quantify the proposed correction. The full correction pipeline was then used to assess differences in metabolic function between scar and healthy myocardium in eight patients with recent acute myocardial infarction using [11C]‐acetate. Data from ten additional patients, injected with [18F]‐FDG, were used to compare the method to the standard electrocardiography (ECG)‐gated approach.ResultsThe proposed method resulted in better recovery (from 32% to 95% on the simulated phantom model) and less residual activity than the standard approach. Higher signal‐to‐noise and contrast‐to‐noise ratios than ECG‐gating were also witnessed (Signal‐to‐noise ratio (SNR) increased from 2.92 to 5.24, contrast‐to‐noise ratio (CNR) increased from 62.9 to 145.9 when compared to a four‐gate reconstruction). Finally, the relevance of this correction using [11C]‐acetate PET patient data, for which erroneous physiological conclusions could have been made based on the uncorrected data, was established as the correction led to the expected clinical results.ConclusionsAn efficient and simple method to correct for the quantitative biases in PET measurements caused by cardiac motion has been developed. Validation experiments using phantom and patient data showed improved accuracy and reliability with this approach when compared to simpler strategies such as gated acquisition or optimal regions of interest (ROI).
Computation and structural elucidation of compounds formed via epoxide alcoholysis
Authors: Alvarenga Elson S. , Teixeira Milena G. , Lopes Dayane T. , Demuner Antonio J. 
Published: December 2018

AbstractIsobenzofuranones are known for their wide range of biological activities such as fungicide, insecticide, and anticancer. The search for novel bioactive compounds was performed by reaction of epoxide 2 with methanol, ethanol, propan‐1‐ol, propan‐2‐ol, and butan‐1‐ol.The mechanism for the stereoselective and stereospecific epoxide opening with methanol was reasoned by calculating the transition states for the two putative structures (rac)‐3a and (rac)‐3b. The compound (rac)‐3a is the kinetic product as inferred from the lower energies of its transition state (TS1). The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts for these two candidate structures were calculated and compared with the experimental data using mean absolute error (MAE) and DP4 analyses. Therefore, the relative stereochemistry of (rac)‐3a was established by the mechanism, MAE, and DP4 approaches. The hydroxyl group was acetylated to surpass the problem of signal overlapping of H5 and H6 in the 1H NMR. The relative stereochemistry of the corresponding ester determined by NMR interpretation was in agreement with the structure of (rac)‐3a.
Surface influence on the rotational and translational dynamics of molecules confined inside a mesoporous carbon xerogel
Authors: Cadar Calin , Ardelean Ioan 
Published: December 2018

AbstractLow‐field nuclear magnetic resonance techniques are employed to extract information about the effects introduced by the interaction with the surface on the rotational and translational dynamics of molecules confined inside a mesoporous carbon xerogel. The molecules under study were water, cyclohexane, and hexane. They were chosen due to their different interaction strength with the carbonaceous matrix. Frequency dependent longitudinal relaxation measurements, using the fast field cycling technique, allowed extraction of the fractal dimension of the carbon xerogel surface. It was observed that the measured value is influenced by the molecule affinity to the surface. Diffusion measurements, using the pulse field gradient technique, have revealed that the stronger interaction with the surface of cyclohexane and hexane molecules leads to an increased diffusive tortuosity, as compared with water.
High‐density quantum dots composites and its photolithographic patterning applications
Authors: Lee Seonwoo , Lee Changhee 
Published: December 2018

With the growing interest in quantum dots (QDs), many applications are emerging recently. In particular, the display industry has shown widespread interest in using QDs as the next generation colorants. One application is to replace conventional color filters with QD‐based color conversion films to significantly improve color purity and luminous efficiency. However, QD blending which is capable of photolithographic patterning is a very challenging problem due to its low dispersion property and aggregations in polar medias. Herein, we report a photo‐patternable QD dispersion that can produce fine patterns through a photolithography process. First, the QDs dispersed in a nonpolar solvent, for example, chloroform or hexane, were separated and dried to obtain a QD powder. And then, the dispersion characteristics of the QD powders were investigated after mixing commercial dispersants and UV curable oligomers. Furthermore, the QD dispersion was investigated up to 30 wt.% of QDs by mixing with various commercial additives. We have studied the optical property changes of QDs during the photocuring process and the heating process prior to actual application. And, we have studied the surface characteristics of the fine QDs patterns after patterning process. As a result, it was confirmed that QDs are able to be well dispersed up to 30 wt.%.
Consequences of using estimated response values from negligible interactions in factorial designs
Authors: Xampeny Rafel , Grima Pere , Tort‐Martorell Xavier 
Published: December 2018

AbstractThis article analyzes the increase in the probability of committing type I and type II errors in assessing the significance of the effects when some properly selected runs have not been carried out, and their responses have been estimated from the interactions considered null from scratch. This is done by simulating the responses from known models that represent a wide variety of practical situations that the experimenter will encounter; the responses considered to be missing are then estimated, and the significance of the effects is assessed. Through comparison with the parameters of the model, the errors are then identified. To assess the significance of the effects when there are missing values, the Box‐Meyer method has been used. The conclusions are that one missing value in eight run designs, and up to three missing values in 16 run designs experiments can be estimated without hardly any notable increase in the probability of error when assessing the significance of the effects.
A semiparametric profile monitoring via residuals
Authors: Siddiqui Zainab , Abdel‐Salam Abdel‐Salam G. 
Published: December 2018

AbstractProfile monitoring is a vast area of research underneath the statistical process monitoring (SPM). Several methods for univariate and multivariate process control are found in literature to monitor the profile data, including parametric, nonparametric, and some semiparametric methods. The main idea behind monitoring the linear profiles in mixed effects is to model the possible individual differences between similar set of profiles for future monitoring. In this paper, nonparametric and semiparametric approaches are proposed to model the profile data in a linear mixed effect setting by considering the residuals from a parametric model. A simulation study was carried out to compare the efficiency of the proposed methods. At first step, the residuals from a parametric linear mixed model are obtained. A nonparametric approach (NPR) is then used to model these residuals. Finally, a semiparametric method (MMRRPM) is proposed as a convex combination of the parametric (P) and nonparametric estimations based on the residuals (NPR) to model the profile data in mix effects. Two Hoteling's T2 statistics were computed for each technique based on fitted values and the estimated random effects. The results show that the proposed methods are most effective to monitor the autocorrelated profile data compared with the state‐of‐the‐art.
High‐precision magnesium isotope analysis of geological and environmental reference materials by multiple‐collector inductively coupled plasma mass spectrometry
Authors: Gao Ting , Ke Shan , Li Ruiying , Meng Xu'nan , He Yongsheng , Liu Chengshuai , Wang Yang , Li Zijian , Zhu Jian‐Ming 
Published: December 2018

RationaleHigh‐precision magnesium (Mg) isotopic analysis for geological and environmental reference materials is a prerequisite to ensure data quality before using Mg isotopes to trace geochemical and environmental processes. However, the Mg‐isotopic ratios of many commonly used reference materials, especially sediments, have rarely been reported. Furthermore, published values for some commonly used reference materials exhibit a significant inconsistency across laboratories and thus need more data comparison.MethodsWe developed different Mg purification schemes for silicate rocks, high‐Ca carbonates and carbonatites, and high‐Mn samples because of their significantly different matrices. We then used synthetic solutions to evaluate potential effects on measurement using multiple‐collector inductively coupled plasma mass spectrometry (MC‐ICP‐MS). The accuracy and precision of our procedures were assessed by measurement on both synthetic solutions and well‐studied geostandards.ResultsThe three different schemes for routine, high‐Ca, and high‐Mn samples can remove matrices efficiently with nearly 100% Mg yield. However, the presence of acid molarity and concentration mismatch, matrix elements, and fluctuations in room temperature can significantly affect the precision and accuracy of Mg isotope analysis, and must be avoided. The Mg isotopic ratios of reference materials obtained in this study are identical to the previously published values within ±0.06‰, verifying that our procedures are robust.ConclusionsThis study presented a thorough set of tests for high precision and accuracy of Mg isotope measurements using MC‐ICP‐MS, which demonstrate reproducibility and accuracy better than 0.05‰ for δ25Mg values and 0.06‰ for δ26Mg values. We reported high‐quality Mg isotopic data for 16 geological and environmental reference materials to aid the inter‐laboratory calibration of Mg isotope measurements in the future.
Synthesis, Characterization, Molecular Docking Studies and Biological Evaluation of Some Conjugated Quinazoline‐Sulfonamide Scaffold
Authors: Kumar A. Sunil , Kudva Jyothi , Bharath B. R. , Rai Vaishali M , Kumar S. Madan , Kumar Vasantha , Sajankila Shyama Prasad 
Published: December 2018

AbstractA series of sulfonamides containing 4‐aminoquinazoline scaffolds 7 a‐7 l was synthesized, characterized and evaluated for their in vitro antitubercular, antimicrobial and anticancer activity. The compounds with 4‐nitrophenyl (7 c), 3‐trifluoromethylphenyl (7 f) and 5‐chloro‐pyridin‐2‐yl (7 h) derivatives have shown potent antitubercular activity against Mycobacterium tuberculosis H37Rv strain and the activity was two‐fold higher than the standard drug Ciprofloxacin. The compounds with 4‐chlorophenyl (7 a), pyridin‐2‐yl (7 g), 5‐chloro‐pyridin‐2‐yl (7 h) and pyrimidin‐2‐yl (7 i, 7 j and 7 k) derivatives were observed as excellent antimicrobial agents. The preliminary toxicity of selected potent compounds was also tested on Red Blood Cells by hemolytic assay and found to be non‐toxic even at higher concentrations. Compounds with 4‐nitrophenyl (7 c) and 4‐fluorophenyl (7 e) substitutions emerged as potent molecules against MDA‐MB‐231 cell line. ADME (Absorption, Distribution, Metabolism and Excretion) screening study revealed that the compounds are strong candidates for antitubercular activity with good ADME parameters. In addition, the structure and antitubercular activity relationship were further supported by molecular docking studies of the active compounds against the DNA topoisomerase II (5BTC) enzyme of M. tuberculosis.
Magnetic Nanofiber Layers as a Functional Surface for Biomolecule Immobilization and One‐Use ‘Sensing in‐a‐Drop’ Applications
Authors: Sanli Serdar , Celik Emine Guler , Demir Bilal , Gumus Z. Pinar , Ilktac Raif , Aksuner Nur , Demirkol Dilek Odaci , Timur Suna 
Published: December 2018

AbstractStabilization of biomolecules on matrices is critically important. Here we constructed composite nanofibers with magnetic features by electro‐spinning of magnetic nanoparticles (MNP) in an appropriate polymer matrix on a collector surface for multiple uses. ‘Poly(vinylalcohol)‐polyethyleneimine/Fe3O4 magnetic nanoparticles’ (PVA‐PEI/MNP) composite nanofiber was used on the screen printed electrodes (SPE) to serve as a platform for the glucose oxidase (GOx) biofilm as the model biomolecule. To show the potential application of this material as a biosensor component, the resulted biofilm, called ‘PVA‐PEI/MNP/GOx’, was fixed on SPE via a neodymium magnet for the electrochemical detection of glucose at −0.7 V where oxygen consumption due to enzymatic reaction was measured. The main advantage of the obtained magnetic biomembrane is that it allows analysis with a single drop. After step‐by‐step surface modifications, analytical characterization was performed using various techniques, such as voltammetry, electrochemical impedance spectroscopy, Fourier‐transform infrared spectroscopy and X‐Ray photoelectron spectroscopy as well as microscopic techniques. The linear range of the PVA‐PEI/MNP/GOx surface was found as 0.0125 to 0.5 mM with a limit of detection of 11.5 μM for glucose as analyte. The application of PVA‐PEI/MNP/GOx for glucose detection in synthetic samples was carried out. Data proved the potential use of the ‘PVA‐PEI/MNP’ surface as a biomolecule immobilization platform for disposable biosensor applications.
A Concise Stereoselective Route to C‐ and P‐ Chirogenic Hydroxypropyl Phosphines by Ring‐Opening of Optically Active Oxaphospholane‐2‐oxide
Authors: Keisar Orit Redy , Ashkenazi Nissan 
Published: December 2018

AbstractA facile, stereoselective method for the synthesis of both carbon‐ and P‐chirogenic phosphine oxides and phosphines bearing a hydroxyl chelating arm was developed. A carefully designed oxaphospholane was constructed via tandem Arbuzov‐ intramolecular cyclization reaction, using commercially available compounds. Regioselective ring opening alkylation/arylation provided optically active phosphine oxides within two synthetic steps. An additional step of stereospecific deoxygenation produced P‐chirogenic tertiary phosphines in high dr.
Brilliant green dye adsorption onto composite snail shell–rice husk: Adsorption isotherm, kinetic, mechanistic, and thermodynamics analysis
Authors: Popoola Lekan Taofeek , Aderibigbe Tajudeen Adejare , Yusuff Adeyinka Sikiru , Munir Musleema Mofehintoluwa 
Published: December 2018

AbstractThis study examined the potential for a composite of snail shell–rice husk (SS‐RH) to successfully remove brilliant green dye (BGD) from aqueous solutions using the batch adsorption method. The adsorbent was synthesized by the calcination process and prepared at a calcination temperature, calcination time, and SS‐RH mixing ratio of 681.10°C, 2.61 hours (h), and 2.61 mixing ratio, respectively. The SS‐RH active functional groups were characterized by the Fourier transform infrared (FTIR) spectroscopy, while examination of its surface morphology was executed by scanning electron microscope. The effects of the BGD's initial concentration, time, pH, solution temperature, adsorbent mass dosage, and rotation speed of the stirrer on it removal were examined. The Langmuir and Sip isotherms fit well for the BGD uptake onto the SS‐RH among the two‐parameter and three‐parameter isotherms examined with R2 values of 0.9995 and 1,000, and optimum adsorption capacities of 129.87 and 123.30 milligrams per gram (mg/g), respectively. Experimental data conformed perfectly using a pseudo‐second‐order kinetic model. The thickness of the boundary layer contributed to the adsorption, as revealed by mechanistic parameters. Thermodynamic adsorption parameters suggested that BGD adsorption onto the SS‐RH was nonspontaneous and endothermic, exhibiting a high level of disorderliness at the solid–liquid interface. The results proved SS‐RH to be a valuable, low‐cost adsorbent for BGD adsorption from aqueous solution.
Carboniferous chondrichthyan assemblages from the Surprise Canyon and Watahomigi formations (latest Mississippian–Early Pennsylvanian) of the western Grand Canyon, Northern Arizona
Authors: Hodnett John-Paul M. , Elliott David K. 
Published: December 2018

AbstractTwo chondrichthyan assemblages of Late Mississippian/Early Pennsylvanian age are now recognized from the western Grand Canyon of northern Arizona. The latest Serpukhovian Surprise Canyon Formation has yielded thirty-one taxa from teeth and dermal elements, which include members of the Phoebodontiformes, Symmoriiformes, Bransonelliformes, Ctenacanthiformes, Protacrodontoidea, Hybodontiformes, Neoselachii (Anachronistidae), Paraselachii (Gregoriidae, Deeberiidae, Orodontiformes, and Eugeneodontiformes), Petalodontiformes, and Holocephali. The euselachian grade taxa are remarkably diverse with four new taxa recognized here; the Protacrodontidae:Microklomax carrieaenew genus new species andNovaculodus billingsleyinew genus new species, and the Anchronistidae:Cooleyella plateranew species andAmaradontus santuciinew genus new species The Surprise Canyon assemblage also has the youngest occurrence of the elasmobranchClairina, previously only known from the Upper Devonian. The Surprise Canyon Formation represents a nearshore fluvial infilling of karstic channels, followed by a shallow marine bioherm reef, and finally deeper open water deposition. The early Bashkirian Watahomigi Formation represents open marine deposition and contains only two taxa: a new xenacanthiform,Hokomata parvanew genus new species, and the holocephalanDeltodus. The relationship between the Surprise Canyon and Watahomigi chondrichthyan assemblages and other significant coeval chondrichthyan assemblages suggests that there may have been eastern and western distinctions among the Euamerican assemblages during the Serpukhovian due to geographic separation by the formation of Pangea.UUID:http://zoobank.org/54a906b6-4873-4f84-92b5-ca0752de01aa
NAMBA FORCING, WEAK APPROXIMATION, AND GUESSING
Authors: COX SEAN , KRUEGER JOHN 
Published: December 2018

AbstractWe prove a variation of Easton’s lemma for strongly proper forcings, and use it to prove that, unlike the stronger principle IGMP, GMP together with 2ω ≤ ω2 is consistent with the existence of an ω1-distributive nowhere c.c.c. forcing poset of size ω1. We introduce the idea of a weakly guessing model, and prove that many of the strong consequences of the principle GMP follow from the existence of stationarily many weakly guessing models. Using Namba forcing, we construct a model in which there are stationarily many indestructibly weakly guessing models which have a bounded countable subset not covered by any countable set in the model.
BROUWER’S FAN THEOREM AND CONVEXITY
Authors: BERGER JOSEF , SVINDLAND GREGOR 
Published: December 2018

AbstractIn the framework of Bishop’s constructive mathematics we introduce co-convexity as a property of subsets B of ${\left\{ {0,1} \right\}^{\rm{*}}}$, the set of finite binary sequences, and prove that co-convex bars are uniform. Moreover, we establish a canonical correspondence between detachable subsets B of ${\left\{ {0,1} \right\}^{\rm{*}}}$ and uniformly continuous functions f defined on the unit interval such that B is a bar if and only if the corresponding function f is positive-valued, B is a uniform bar if and only if f has positive infimum, and B is co-convex if and only if f satisfies a weak convexity condition.
INTERPRETABLE SETS IN DENSE O-MINIMAL STRUCTURES
Authors: JOHNSON WILL 
Published: December 2018

AbstractWe give an example of a dense o-minimal structure in which there is a definable quotient that cannot be eliminated, even after naming parameters. Equivalently, there is an interpretable set which cannot be put in parametrically definable bijection with any definable set. This gives a negative answer to a question of Eleftheriou, Peterzil, and Ramakrishnan. Additionally, we show that interpretable sets in dense o-minimal structures admit definable topologies which are “tame” in several ways: (a) they are Hausdorff, (b) every point has a neighborhood which is definably homeomorphic to a definable set, (c) definable functions are piecewise continuous, (d) definable subsets have finitely many definably connected components, and (e) the frontier of a definable subset has lower dimension than the subset itself.
THE ELLIS GROUP CONJECTURE AND VARIANTS OF DEFINABLE AMENABILITY
Authors: JAGIELLA GRZEGORZ 
Published: December 2018

AbstractWe consider definable topological dynamics forNIPgroups admitting certain decompositions in terms of specific classes of definably amenable groups. For such a group, we find a description of the Ellis group of its universal definable flow. This description shows that the Ellis group is of bounded size. Under additional assumptions, it is shown to be independent of the model, proving a conjecture proposed by Newelski. Finally we apply the results to new classes of groups definable in o-minimal structures, generalizing all of the previous results for this setting.
ON CONSTRAINTS AND DIVIDING IN TERNARY HOMOGENEOUS STRUCTURES
Authors: KOPONEN VERA 
Published: December 2018

AbstractLet ${\cal M}$ be ternary, homogeneous and simple. We prove that if ${\cal M}$ is finitely constrained, then it is supersimple with finite SU-rank and dependence is k-trivial for some k &lt; ω and for finite sets of real elements. Now suppose that, in addition, ${\cal M}$ is supersimple with SU-rank 1. If ${\cal M}$ is finitely constrained then algebraic closure in ${\cal M}$ is trivial. We also find connections between the nature of the constraints of ${\cal M}$, the nature of the amalgamations allowed by the age of ${\cal M}$, and the nature of definable equivalence relations. A key method of proof is to “extract” constraints (of ${\cal M}$) from instances of dividing and from definable equivalence relations. Finally, we give new examples, including an uncountable family, of ternary homogeneous supersimple structures of SU-rank 1.