bluuebunny/crossref_metadata_2025_split huggingface dataset:
Incorporation of Metallic Species into Midblock‐Sulfonated Block Ionomers
Authors: Deng Jing , Yan Jiaqi , Tilly Joseph C. , Deng Liyuan , Mineart Kenneth P. , Spontak Richard J. 
Published: August 2018

AbstractBlock ionomers can, in the same fashion as their neutral block copolymer analogs, microphase‐order into various nanoscale morphologies. The added benefit of a copolymer possessing a charged species is that the resultant block ionomer becomes amphiphilic and capable of imbibing polar liquids, including water. This characteristic facilitates incorporation of metallic species into the soft nanostructure for a wide range of target applications. In this study, the nonpolar and polar constituents of solvent‐templated midblock‐sulfonated block ionomers (SBIs) are first selectively metallated for complementary morphological analysis. Next, four different salts, with cationic charges ranging from +1 to +3, are introduced into three hydrated SBIs varying in their degree of sulfonation (DOS), and cation uptake is measured as a function of immersion time. These results indicate that uptake generally increases with increasing salt concentration, cationic charge, and specimen DOS. Swelling and nanoindentation measurements conducted at ambient temperature demonstrate that water uptake decreases, while the surface modulus increases, with increasing cationic charge. Chemical spectra acquired from energy‐dispersive X‐ray spectroscopy (EDS) confirm the presence of each of the ion‐exchanged species, and corresponding EDS chemical maps reveal that the spatial distribution of these species is relatively uniform throughout the block ionomer films.
Tracing scientific reasoning in psychiatry: Reporting of statistical inference in abstracts of top journals 1975–2015
Authors: Baethge Christopher , Deckert Markus , Stang Andreas 
Published: August 2018

AbstractObjectiveTo analyze the reporting of statistical inference in psychiatry.MethodWe searched 63,928 abstracts, published in 15 leading psychiatric journals (1975–2015).ResultsMedian abstract length increased from 664 (1975) to 1,323 (2015) characters, and median use of numbers from two to 14/abstract. A total of 3.6% of all abstracts exclusively contained significance terminology in a nonstatistical sense, and 45% showed some form of statistical inference, increasing from 26% to 52%. In those abstracts, statistical inference based on thresholds was dominant. Its proportion decreased from 99% to 66%, but with rising numbers of articles, figures rose from 1,095 to 2,382. Although reporting p values without thresholds did not appear 40 years ago and remains rare, combining precise p values with thresholds is now common. In 2010–2015, 86% of abstracts contained p values or p value thresholds, 22% confidence intervals, and 7% confidence intervals only. Results varied across journals.ConclusionThere is a moderate shift from reporting p values along set thresholds, such as p ≤ 0.05, to presenting precise p values and confidence intervals, but not as pronounced as in epidemiology and general medicine. The long debate on estimation over testing has not led to a substantial replacement of p values by confidence intervals. Null hypothesis testing (“p ≤ .05”) dominates statistical thinking.
Accelerating compressed sensing in parallel imaging reconstructions using an efficient circulant preconditioner for cartesian trajectories
Authors: Koolstra Kirsten , van Gemert Jeroen , Börnert Peter , Webb Andrew , Remis Rob 
Published: August 2018

PurposeDesign of a preconditioner for fast and efficient parallel imaging (PI) and compressed sensing (CS) reconstructions for Cartesian trajectories.TheoryPI and CS reconstructions become time consuming when the problem size or the number of coils is large, due to the large linear system of equations that has to be solved in
and
‐norm based reconstruction algorithms. Such linear systems can be solved efficiently using effective preconditioning techniques.MethodsIn this article we construct such a preconditioner by approximating the system matrix of the linear system, which comprises the data fidelity and includes total variation and wavelet regularization, by a matrix that is block circulant with circulant blocks. Due to this structure, the preconditioner can be constructed quickly and its inverse can be evaluated fast using only two fast Fourier transformations. We test the performance of the preconditioner for the conjugate gradient method as the linear solver, integrated into the well‐established Split Bregman algorithm.ResultsThe designed circulant preconditioner reduces the number of iterations required in the conjugate gradient method by almost a factor of 5. The speed up results in a total acceleration factor of approximately 2.5 for the entire reconstruction algorithm when implemented in MATLAB, while the initialization time of the preconditioner is negligible.ConclusionThe proposed preconditioner reduces the reconstruction time for PI and CS in a Split Bregman implementation without compromising reconstruction stability and can easily handle large systems since it is Fourier‐based, allowing for efficient computations.
Yield design‐based numerical analysis of three‐dimensional reinforced concrete structures
Authors: Vincent Hugues , Arquier Mathieu , Bleyer Jérémy , de Buhan Patrick 
Published: August 2018

SummaryThe objective of this contribution is to present some new recent developments regarding the evaluation of the ultimate bearing capacity of massive three‐dimensional reinforced concrete structures which cannot be modeled as 1D (beams) or 2D (plates) structural members. The approach is based upon the implementation of the lower bound static approach of yield design through a discretization of the three‐dimensional structure into tetrahedral finite elements, on the one hand, the formulation of the corresponding optimization problem in the context of semi‐definite programming techniques, on the other hand. Another key feature of the method lies in the treatment of the concrete‐embedded reinforcing bars not as individual elements, but by resorting to an extension of the yield design homogenization approach. The whole procedure is first validated on the rather simple illustrative problem of a uniformly loaded simply supported beam, then applied to the design of a bridge pier cap taken as an example of more complex and realistic structure.
Prognostic Value of the ESPEN Consensus and Guidelines for Malnutrition: Prediction of Post‐Discharge Clinical Outcomes in Older Inpatients
Authors: Sánchez‐Rodríguez Dolores , Annweiler Cédric , Ronquillo‐Moreno Natalia , Vázquez‐Ibar Olga , Escalada Ferran , Duran Xavier , Muniesa Josep M. , Marco Ester 
Published: August 2018

AbstractIntroductionOur study aimed to determine whether malnutrition and nutrition‐related conditions using the European Society for Clinical Nutrition and Metabolism (ESPEN) consensus were associated with functional status, institutionalization, readmissions, and mortality in older patients at 3‐month follow‐up.MethodsA cohort of 102 consecutive deconditioned patients was assessed at 3 months postdischarge from postacute geriatric care. Inclusion criteria were age ≥70 years, scores of Mini‐Mental Status Examination ≥21/30, and being admitted for rehabilitation after an acute non‐disabling disease. Malnutrition as defined by ESPEN consensus and nutrition‐related conditions (such as frailty, sarcopenia, overweight/obesity, nutrient deficiency, and cachexia) was assessed, and related to postdischarge clinical outcomes at 3‐month follow‐up.ResultsOf 95 included patients (84.5 ± 6.5 years; 63.2% women), 31 had unintentional weight loss and 19 fulfilled malnutrition criteria defined by the ESPEN consensus. Nutrition‐related conditions were frequent: 94 patients had frailty, 44 sarcopenia, 58 overweight/obesity, and 59 nutrient deficiency. Sarcopenia reduced functional status at 3‐month follow‐up (median difference: −25.5; 95% confidence interval (CI) −46.4 – −4.3, P = 0.008). Institutionalization was related to unintentional weight loss in univariate analysis (odds ratio (OR) = 3.9; 95%CI 1.3 – 12.4, P = 0.018). Meeting the basic ESPEN definition of malnutrition was related to institutionalization in univariate (OR = 3.4; 95%CI 1.0 to 11.3, P = 0.042) but not multivariate analysis, and was not significantly associated with readmissions or mortality at 3‐month follow‐up.ConclusionsFurther research is needed on the potential value of the ESPEN consensus and guidelines for malnutrition to identify older patients at risk of worse functional status, institutionalization, readmissions, and mortality at 3‐month follow‐up postdischarge.
Meshfree modeling of a fluid‐particle two‐phase flow with an improved SPH method
Authors: Zhang Z. L. , Walayat K. , Chang J. Z. , Liu M. B. 
Published: August 2018

SummaryFluid‐particle two‐phase flows are very complex and quite challenging to numerically simulate due to the complex and constantly moving fluid‐particle interface. Recent developments in meshfree and particle methods provide alternatives in modeling fluid flows with moving boundaries. In this paper, a modified smoothed particle hydrodynamics (SPH) method is developed to simulate particle sedimentation (two‐dimensional) in Newtonian fluids. The modified SPH includes an enhanced particle approximation scheme, an effective solid boundary treatment algorithm, the artificial stress model, and a turbulence model. By decoupling a field variable and its derivatives in a finite particle method, a decoupled finite particle method is presented, which balances accuracy, efficiency, and stability in SPH simulations without the necessity of solving redundant and challenging corrective matrix equations. A coupled dynamic solid boundary treatment is developed to improve the accuracy near the fixed and moving solid boundaries. The artificial stress term is added into the SPH equations of motion to remove the possible tensile instability phenomenon. The large eddy simulation model is incorporated into the SPH to describe the turbulence effects at high Reynolds numbers. Four different particle sedimentation tests are conducted using the modified SPH along with the finite element fictitious boundary method. It is demonstrated that the improved SPH method can achieve much better results than the conventional SPH while showing a good comparison with the results from the finite element fictitious boundary method and from other sources.
Adaptive BDDC algorithms for the system arising from plane wave discretization of Helmholtz equations
Authors: Peng Jie , Wang Junxian , Shu Shi 
Published: August 2018

SummaryBalancing domain decomposition by constraints algorithms with adaptive primal constraints are developed in a concise variational framework for the weighted plane wave least‐squares discretization of Helmholtz equations with high and various wave numbers. The unknowns to be solved in this preconditioned system are defined on elements rather than vertices or edges, which are different from the well‐known discretizations such as the classical finite element method. Through choosing suitable “interface” and appropriate primal constraints with complex coefficients and introducing some local techniques, we developed a two‐level adaptive balancing domain decomposition by constraints algorithm for the plane wave least‐squares discretization, and the condition number of the preconditioned system is proved to be bounded above by a user‐defined tolerance and a constant that is only dependent on the maximum number of interfaces per subdomain. A multilevel algorithm is also attempted to resolve the bottleneck in large‐scale coarse problem. Numerical results are carried out to confirm the theoretical results and illustrate the efficiency of the proposed algorithms.
Construction of the Pentacyclic Core and Formal Total Synthesis of (rac)‐Renieramycin T
Authors: Kimura Shinya , Saito Naoki 
Published: August 2018

AbstractA formal total synthesis of the antitumor marine natural product (rac)‐renieramycin T, which possesses a characteristic ecteinascidin‐type A ring in the renieramycin–saframycin core skeleton, was elaborated. The key steps in the synthesis of (rac)‐renieramycin T are a modified Pictet–Spengler cyclization of dialkylated oxomalonate derivatives and decarboxylation via a monocarboxylic acid derivative followed by stereocontrolled protonation of the enol intermediate. A key intermediate in our previous synthesis of renieramycin T was used, and the formal synthesis was accomplished in 21 steps from a known piperazine‐2,5‐dione derivative.
Electrochemical sensor based on nanostructured ion imprinted polymer for the sensing and extraction of Cr(III) ions from industrial wastewater
Authors: Aravind Archana , Mathew Beena 
Published: August 2018

ABSTRACTIn the present study we prepared a novel ion imprinted polymer as a sensitive electrochemical sensor for the determination of Cr(III) ion. The Cr(III) ion imprinted polymer was fabricated on a platinum electrode. Due to the presence of a nanolayer on the ion imprinted polymer with specific binding sites, the sensor reacted quickly to Cr(III) ion and can be used for selective extraction of Cr(III) ion. The Cr(III) ion imprinted polymer was prepared by using methacrylic acid as the functional monomer, N,N'‐methylene‐bis‐acrylamide as the crosslinking agent, potassium peroxodisulfate as initiator and Cr(III) ion as the template molecule. Non‐imprinted polymers were also prepared for comparative studies. The synthesized polymer was characterized using Fourier transform IR spectroscopy, TEM, Energy‐dispersive X‐ray spectroscopy and XRD. The limit of detection of the platinum–mutiwalled carbon nanotube ion imprinted polymer sensor was found to be 0.051 µmol L–1 using differential pulse voltammetry. Moreover, the proposed method was effectively used for the sensing and extraction of Cr(III) ion in real samples collected from the metal plating industry. © 2018 Society of Chemical Industry
High‐efficiency flexible III‐V photovoltaic solar cells based on single‐crystal‐like thin films directly grown on metallic tapes
Authors: Pouladi Sara , Rathi Monika , Khatiwada Devendra , Asadirad Mojtaba , Oh Seung Kyu , Dutta Pavel , Yao Yao , Gao Ying , Sun Sicong , Li Yongkuan , Shervin Shahab , Lee Keon‐Hwa , Selvamanickam Venkat , Ryou Jae‐Hyun 
Published: August 2018

AbstractThis study demonstrates the first flexible single‐junction III‐V photovoltaic solar cells (SCs) based on single‐crystal‐like gallium arsenide (GaAs) thin films on a low‐cost metal substrate by direct and continuous deposition, which can bypass expensive single crystal wafer fabrication. The two‐dimensional modeling of the GaAs SC is developed and used to study feasibility of single‐crystal‐like GaAs thin films for high performance SC devices. A promising SC device performance characteristic with an open‐circuit voltage of 560 mV and short circuit current of 19.4 mA/cm2, resulting in a conversion efficiency of ~7.6%, is demonstrated.
Approaches for synthesis of soluble poly(3,6‐dihydroxy‐2,7‐carbazole) with phenolic function
Authors: Aso Fumihiro , Kawashima Hidehisa , Kijima Masashi 
Published: August 2018

ABSTRACTPoly(N‐alkyl‐3,6‐dihydroxy‐2,7‐carbazole) which should be soluble and have phenolic function was synthesized through different two routes. The former method was a direct synthesis by polymerizing a 2,7‐dibromo‐3,6‐dihydroxycarbazole monomer using Ni(cod)2, which only gave a low molecular weight polymer. The latter method was an ether cleavage reaction of methoxy groups in a precursor polymer, poly(3,6‐dimethoxycarbazole), using BBr3, which gave successfully the objective polymer that has a number average molecular weight of 4300 g/mol comparable to the precursor polymer. They showed large spectral changes in photoabsorption and fluorescence on addition of base. They also showed redox behavior similar to a hydroquinone/benzoquinone couple investigated by cyclic voltammetry. These new functions could be derived from the phenolic hydroxy group in the carbazole unit. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2039–2044
Effects of alkyl side chain length of low bandgap naphtho[1,2‐c:5,6‐c′]bis[1,2,5]thiadiazole‐based copolymers on the optoelectronic properties of polymer solar cells
Authors: Tong Junfeng , An Lili , Li Jianfeng , Lv Jie , Guo Pengzhi , Li Liujun , Zhang Peng , Yang Chunyan , Xia Yangjun , Wang Chenglong 
Published: August 2018

ABSTRACTTwo donor‐π‐acceptor (D‐π‐A) type naphtho[1,2‐c:5,6‐c′]bis[1,2,5]thiadiazole (NT)‐based conjugated copolymers (CPs), namely, PBDT‐TT‐DTNT‐HD and PBDT‐TT‐DTNT‐OD, containing different side chain length (2‐hexyldecyl, HD and 2‐octyldodecyl, OD) anchoring to thiophene π‐bridge between the two‐dimensional (2D) 5‐((2‐butyloctyl)thieno[3,2‐b]thiophen‐2‐yl)benzo[1,2‐b:4,5‐b′]dithiophene (BDT‐TT) unit and NT moiety are developed and fully characterized. The resultant two copolymers exhibited broader absorption in wide range of 300–820 nm and obviously deepened EHOMO of approximately −5.50 eV. The effects of side chain length on film‐forming ability, absorption, energy levels, aggregation, dielectric constant (ɛr), mobility, morphology, and photovoltaic properties are further systematically investigated. It was found that the side chain length had little impact on solution‐processability, absorption, energy levels, and aggregation in CB solution of resultant CPs. However, tinily increasing side chain length promoted to form the more ordered structure of neat polymer film even if the corresponding ɛr decreased. As a result, the side‐chain‐extended PBDT‐TT‐DTNT‐OD:PC71BM‐based device achieved 32% increased FF than that of PBDT‐TT‐DTNT‐HD:PC71BM and thus the PCE was significantly raised from 3.99% to 5.21%, which were benefited from 2 times higher SCLC hole mobility, more favorable phase separation, and improved exciton dissociation. These findings could provide an important and valuable insight by side chain modulation for achieving efficient PSCs. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2059–2071
Construction of excellent thermal latent system for the synthesis of networked epoxide polymers by sulfonium salts
Authors: Kawaoka Yoshiaki , Koge Katsushige , Sudo Atsushi , Endo Takeshi 
Published: August 2018

ABSTRACTAn efficient thermally latent initiation system using dual sulfonium salts, consisting S‐benzylsulfonium salt 1 bearing
counter anion and S,S‐dimethylsulfonium salt 2 bearing CH3
counter anion, has been developed for the cationic polymerization of epoxides. Compared to the conventional system using 1 as a thermally latent initiator, the newly developed system allowed significant improvement of stability of epoxy formulations during storage at ambient temperature without sacrificing their curability at elevated temperatures. Such a remarkable performance is attributable to the nucleophilic attack of CH3
to cationic species formed unavoidably by the reaction of 1 with epoxide. Such entrapment of cationic species into the corresponding dormant led to the inhibition of undesirable chain growth of polymers during storage of epoxy formulations. In addition, the dormant can undergo dissociation at elevated temperature to give cationic species, which can readily initiate the polymerization of epoxide. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2096–2102
Study on Post‐Polymerization Modification of Ring‐Opening Metathesis Polymers Involving Pendant Thiolactone Units
Authors: Baysak Elif , Daglar Ozgun , Saim Gunay Ufuk , Hizal Gurkan , Tunca Umit , Durmaz Hakan 
Published: August 2018

ABSTRACTTwo different oxanorbornene monomers were prepared and copolymerized with butyl‐functionalized oxanorbornene monomer through the ring‐opening metathesis polymerization. The resulting polymers were then subjected to the aminolysis reactions with propylamine (PA) in the presence of methyl acrylate (MA) to capture, in situ, the latent thiol. It was found that the polymer, in which the thiolactone unit is close to the polymer backbone, did not undergo an efficient aminolysis reaction even an excess amount of PA was utilized, while the other polymer, in which the thiolactone unit away from the polymer backbone, did efficiently undergo aminolysis reaction even PA was used in low amounts. Besides, a variety of primary amine compounds along with MA were reacted with the polymer, in which the thiolactone group away from the polymer backbone, to test their reactivity toward the aminolysis reactions. All modified polymers were characterized by using conventional instruments such as gel permeation chromatography, nuclear magnetic resonance, and differential scanning calorimetry. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2145–2153
Effect of heat and singeing on stable hydrogen isotope ratios of bird feathers and implications for their use in determining geographic origin
Authors: Vander Zanden Hannah B. , Reid Abigail , Katzner Todd , Nelson David M. 
Published: August 2018

RationaleStable hydrogen isotope (δ2H) ratios of animal tissues are useful for assessing movement and geographic origin of mobile organisms. However, it is uncertain whether heat and singeing affects featherδ2H values and thus subsequent geographic assignments. This is relevant for birds of conservation interest that are burned and killed at concentrating solar‐energy facilities that reflect sunlight to a receiving tower and generate a solar flux field.MethodsWe used a controlled experiment to test the effect of known heat loads (exposure to 200, 250 or 300°C for 1 min) on the morphology andδ2H values of feathers from two songbird species. Subsequently, we examined the effects of singeing onδ2H values of feathers from three other songbird species that were found dead in the field at a concentrating solar‐energy facility.ResultsRelative to control samples, heating caused visual morphological changes to feathers, including shriveling at 250°C and charring at 300°C. Theδ2H values significantly declined by a mean of 27.8‰ in experimental samples exposed to 300°C. There was no statistically detectable difference betweenδ2H values of the singed and unsinged portions of field‐collected feathers from the same bird.ConclusionsLimited singeing that did not dramatically alter the feather morphology did not substantially affectδ2H values of feathers from these songbirds. However, higher temperatures induced charring and reducedδ2H values. Therefore, severely charred feathers should be avoided when selecting feathers forδ2H‐based assessment of geographic origin.