bluuebunny/crossref_metadata_2025_split huggingface dataset:
Non‐Covalent Substrate Directed Enantioselective Heck Desymmetrization of cis‐Cyclohex‐4‐ene‐1,2‐diol: Synthesis of all cis Chiral 5‐Aryl‐cyclohex‐3‐ene‐1,2‐diols and Mechanistic Investigation
Authors: Angnes Ricardo A. , Thompson Lee M. , Mashuta Mark S. , Correia Carlos R. D. , Hammond Gerald B. 
Published: July 2018

AbstractEnantioselective substrate directed Heck reactions are desirable for the stereoselective synthesis of complex molecules. However, due to the coordination requirements of both chiral ligands and directing groups, such methodologies are underdeveloped. We report herein the desymmetrization of meso (1R,2S)‐cyclohex‐4‐ene‐1,2‐diol in an enantioselective and substrate directed fashion. The method provides all cis substituted highly functionalized chiral allylic alcohols in a complementary fashion to other Heck protocols.The products were obtained in high enantioselectivities (higher than 95% ee) and moderate to high yields (38–87%). The noncovalent interactions responsible for the directing effect were elucidated through computational examination of relevant minima and transition structures.magnified image
Microwave‐Assisted and Base‐Promoted Domino Reaction of Cyclic N‐Sulfonyl Ketimines with α,β‐Disubstituted Nitroalkenes: A Green Access to 2‐Hydroxyarylpyridines
Authors: Guin Soumitra , Majee Debashis , Biswas Soumen , Samanta Sampak 
Published: July 2018

AbstractMicrowave‐assisted and organobase‐promoted eco‐friendly one‐pot protocol has been developed to construct an interesting class of pyridyl‐substituted phenols/α‐naphthols containing a carboxylate or aroyl group at C2 position on the pyridine ring. A series of N‐sulfonyl ketimines and different kinds of bielectrophiles, such as MBH acetates of nitroalkenes/α‐arylacetylenyl‐β‐arylnitroolefins, were involved in this cyclization process, which delivers good to high yields of aforementioned heterocycles and excels with several compatible functionalities.
Gold‐Catalyzed Transformations of Propargyl Alcohols and Propargyl Amines
Authors: Zhang Bing , Wang Tao 
Published: July 2018

AbstractPropargyl alcohols and propargyl amines are useful building blocks for the synthesis of heterocycles and complex molecules. The development of homogeneous gold catalysis has greatly benefited organic synthesis. This Focus Review presents an overview of the gold‐catalyzed transformations of propargyl alcohols and amines.
Synthesis and Cytotoxicity of (±)‐9‐Hydroxy‐5‐oxo‐2,3,4,5‐tetrahydro‐1H‐benzo[b]azepine‐2‐carboxamide: An Active Component of Juglans regia
Authors: Marepu Nagaraju , Yeturu Sunandamma , Pal Manojit 
Published: July 2018

AbstractA total synthesis of a benzazepine natural product was achieved via an alternative strategy using a Strecker‐type synthesis/Heck coupling process to construct the core ring. A comparison of spectral data of the target molecule with the previously reported one suggested the need for structure revision. The compound described herein also showed cytotoxic properties.
3‐Cyano Imidazopyridine Acceptor‐based Bipolar andn‐type Host Materials for Phosphorescent Organic Light‐Emitting Diodes
Authors: Kothavale Shantaram , Lee Kyung Hyung , Lee Jun Yeob 
Published: July 2018

AbstractTwo host materials named 8‐(3‐(9H‐carbazol‐9‐yl)phenyl)‐2‐phenylimidazo[1,2‐a]pyridine‐3‐carbonitrile (mCzImPy) and 8,8′‐(1,3‐phenylene)bis(2‐phenylimidazo[1,2‐a]pyridine‐3‐carbonitrile) (mBisImPy) were synthesized as a bipolar host and a n‐type host, respectively, from the herocyclic imidazopyridine unit through its 3‐position CN modification. They worked as the hosts of yellow phosphorescent emitter and the mCzImPy host achieved high quantum efficiency of 18.2% in the yellow phosphorescent devices. Therefore, the 3‐cyanoimidazopyridine showed potential as an electron transport unit of host design.
Numerical investigation on sealing behaviors of an extremely high‐speed two‐stage impellers structure in cryogenic rockets
Authors: Ma Yuan , Li Yanzhong , Xie Fushou , Wang Lei , Zhu Kang 
Published: July 2018

AbstractAiming at a high‐speed‐impeller mechanical seal structure that plays a significant role in the oxidant turbopump of cryogenic rocket systems, the computational fluid dynamic approach is introduced to analyze its working performance, including the phase distribution in the flow channel, the cooling effect of the frictional element, and the sealing function as well as the power consumptions of the impellers. The established periodic 3D model, which could simultaneously account for the turbulent flow, coupled heat transfer, cavitation, and evaporation, as well as the change of thermophysical properties, was successfully verified by the experimental data. The results show that the sealing ability of a totally liquid‐filled impeller would increase with increasing rotational speed, blade size, and density of the working fluid. After the rotational speed increasing over a certain value (14,000 r/min in this case), a dynamically steady gas–liquid interface would be maintained at the Impeller II's blades, which indicates the completely effective sealing of liquid. Meanwhile, the friction surface could be effectively cooled by this two‐stage leakage cooling scheme, and its maximum temperature could be stably controlled at the rated speed. Based on the good sealing performance and effective cooling, this high‐speed‐impeller seal structure was proved to be feasible and available for cryogenic rocket systems.
Adaptive tilting angles to achieve high‐precision scanning of a dual probes AFM
Authors: Wu Jim‐Wei , Lo Yu‐Ting , Liu Wei‐Chih , Liu Da‐Wei , Chang Kuang‐Yao , Fu Li‐Chen 
Published: July 2018

AbstractAtomic force microscopy (AFM) is a powerful measurement tool, widely used in microfabricated structure inspection. However, since it is typical that the fixed tilting angle of a probe is employed in traditional AFM, the corner and sidewall image of the scanned sample would be distorted. To overcome the problem, a so‐called adaptive tilting angle algorithm (ATAA) applied to a self‐designed dual‐probe AFM system is presented to achieve on‐line sidewall estimation during scanning of general samples. Through the use of the proposed ATAA, the tilting angles of dual probes for each scan line can be self‐adjusted to the optimal ones. Overall, a probe tilt mechanism is designed, which allows the AFM system to change the tilting angles of the probes during the scanning process such that the dual‐probe structure AFM can acquire a complete high precision image with just a single scan. The experimental results show the performance of sidewall measurement and the high‐precision image obtained by the proposed method.
Functional and anatomical connectivity‐based parcellation of human cingulate cortex
Authors: Jin Fei , Zheng Pengpeng , Liu Huaigui , Guo Hui , Sun Zhihua 
Published: July 2018

AbstractIntroductionHuman cingulate cortex (CC) has been implicated in many functions, which is highly suggestive of the existence of functional subregions.MethodsIn this study, we used resting‐state functional magnetic resonance imaging (rs‐fMRI) and diffusion tensor imaging (DTI) to parcellate the human cingulate cortex (CC) based on resting‐state functional connectivity (rsFC) patterns and anatomical connectivity (AC) patterns, to analyze the rsFC patterns and the AC patterns of different subregions, and to recognize whether the parcellation results obtained by the two different methods were consistent.ResultsThe CC was divided into six functional subregions, including the anterior cingulate cortex, dorsal anterior midcingulate cortex, ventral anterior midcingulate cortex, posterior midcingulate cortex, dorsal posterior cingulate cortex, and ventral posterior cingulate cortex. The CC was also divided into ten anatomical subregions, termed Subregion 1 (S1) to Subregion 10 (S10). Each subregion showed specific connectivity patterns, although the functional subregions and the anatomical subregions were internally consistent.ConclusionsUsing different model MRI images, we established a parcellation scheme, which is internally consistent for the human CC, which may provide an in vivo guide for subregion‐level studies and improve our understanding of this brain area at subregional levels.
A multi‐GPU finite element computation and hybrid collision handling process framework for brain deformation simulation
Authors: Tian Ye , Hu Yong , Shen Xukun 
Published: July 2018

AbstractThis paper offers a fast multi‐graphics processing unit (GPU) parallel simulation framework to the problem of real‐time and nonlinear finite element computation of brain deformation. A load balancing strategy is proposed to ensure the efficient distribution of nonlinear finite element computation on multi‐GPU. A data storage structure is designed to minimize the amount of data transfer and make full use of the overlay technique of GPU to reduce the transferring latency between multi‐GPUs. We further present a fast central processing unit (CPU)–GPU parallel continuous collision detection and response method, which not only can deal with the collision between the brain and skull but also can handle the self‐collision of the brain. Our method can make full use of CPU and GPU to implement a parallel computation about deformation and collision detection. Our experimental results show that our method is able to handle a brain geometric model with high detail gyrus composed of more than 40,000 tetrahedron elements. This can facilitate the fidelity of the current virtual brain surgery simulator. We evaluate our approach qualitatively and quantitatively and compare it with related works.
“Zero Reference” During Cardiac Catheterization
Authors: Waldman J.D. , Loeffler T.S. , Turner S.W. , Pappelbaum S.J. 
Published: July 2018

Hemodynamic pressure measurements obtained during cardiac catheterization studies are calibrated to an arbitrary level where the pressure is considered zero. Despite the fundamental nature of the zero reference level, there is no standardized method for determination of “zero reference.”A horizontal metal rod has been constructed to be level with the pressure transducer domes. With lateral radiographic viewing, the metal rod is adjusted to be level with the junction of the inferior vena cava and the right atrium. The technique is rapid, reliable, without risk and allows accurate comparison of hemodynamic data between patients and in the same patient longitudinally.
Trade‐off between seed yield components and seed composition traits in sea level quinoa in response to sowing dates
Authors: Curti Ramiro N. , Sanahuja María del Carmen , Vidueiros Silvina M. , Pallaro Anabel N. , Bertero Héctor Daniel 
Published: July 2018

AbstractBackground and objectivesThe relative influences of genetic and environmental factors on seed composition traits as well as the interrelations among these attributes and seed yield are largely unknown in quinoa. These aspects are approached here through experiments conducted at a low elevation temperate environment with four quinoa genotypes sown at three dates and the hypothesis that variation in seed composition traits can be explained by the relative embryo size was tested.FindingsThere was an important range of variation for almost all seed composition traits, and the genotype‐by‐sowing date (G × S) interaction effect was significant for yield and its components plus protein and oil concentrations. Variation in fat and protein concentration was associated with embryo and seed size but not with relative embryo size (trait indifferent to environmental and genetic factors). A winter sowing date induced positive associations between fat and carbohydrate concentrations, seed, and embryo weight, but negative associations among almost all of these traits and seed yield and protein content. On the other hand, a mid‐spring sowing date induced positive associations between seed yield and protein content.ConclusionsWinter sowing dates are suited for obtaining heavier seeds associated with higher fat and carbohydrates concentrations under the explored conditions; whereas under mid‐spring sowings higher seed yield, associated with high protein content but at the expense of smaller seeds are achieved.Significance and noveltyVariability in the main seed composition traits in sea level quinoa cultivars was explained mostly by G × S interaction. The choice of genotypes and sowing dates that modify the trade‐offs between the main yield and seed composition traits might contribute to obtain a specific quality and higher yields. Variation in protein and fat concentrations was no associated with the relative embryo size.
Atrial fibrillation, an epiphenomenon of acute Stanford type‐A aortic dissection with suspected intimo‐intimal intussusception
Authors: Ciulla Michele M. , Vivona Patrizia , Lemos Alessandro , Sozzi Fabiola , Cioffi Ugo , Testori Alberto 
Published: July 2018

Key Clinical MessageSupraventricular arrhythmias can sometimes be “only” epiphenomena appearing during acute hypoxia, pneumonia, pulmonary embolism, and thrombosis. Indeed, atrial fibrillation is not rare in acute aortic dissection as it is estimated in about one half of patients and may be secondary to a perfusion deficit of the sinoatrial node artery.
Exergy, Exergoeconomic and Enviroeconomic Evaluation of a Biomass Boiler‐Steam Engine Micro‐CHP System
Authors: Açıkkalp Emin , Zeng Thomas , Ortwein Andreas , Burkhardt Holger , Klenk Werner 
Published: July 2018

AbstractBiomass‐based micro‐combined heat‐and‐power (CHP) systems could play an important role in future renewable energy systems by providing net stability and balance electricity fluctuations from wind and solar systems by demand‐driven and base load operations. A biomass boiler‐steam engine micro‐CHP system was investigated via exergy‐based analysis methods to evaluate the optimization potential concerning exergy, environmental, and economic aspects. It was shown that the system has low exergy efficiency compared to systems from the literature and that the boiler is mainly affected by capital cost. Major improvements in terms of exergy efficiency as well as economics should therefore be focused on the boiler.
Effects of Steam Addition during Calcination on Carbonation Behavior in a Calcination/Carbonation Loop
Authors: Chou Yiang-Chen , Cheng Jui-Yen , Liu Wan-Hsia , Hsu Heng-Wen 
Published: July 2018

AbstractThe effects of steam addition during calcination on the carbonation behavior of calcium‐based sorbents in cyclic calcination/carbonation experiments were investigated. Variations in the CaO conversion rate during carbonation were measured to evaluate the influence of operating conditions and particle size on the carbonation reaction in kinetic‐ and diffusion‐controlled reaction regimes. Surface sintering and particle aggregation during cyclic calcination/carbonation affected the sorbent surface area, pore volume, and possibly the pore size, resulting in less sorbent recyclability and a trigger time retard in the fast kinetic‐controlled carbonation. Steam addition during calcination positively affected the recyclability of the sorbents and altered the carbonation behavior.
Monitoring biological processes using univariate statistical process control
Authors: Mansouri Majdi , Al‐Khazraji Ayman , Yin Teh Sin , Harkat Mohamed‐Faouzi , Nounou Hazem , Nounou Mohamed 
Published: July 2018

AbstractBiological modelling is a challenging task specifically when state variables are difficult or even impossible to be measured. Consequently, monitoring quality of biological process will be impacted negatively due to the lack of an accurate model capable of reflecting precisely the process dynamics. Moreover, the faults in such systems cannot be detected robustly. The current work proposes a novel approach that combines state estimation with process monitoring techniques. The developed approach, named as particle filter (PF)'based multiscale maximum double exponentially weighted moving average (MS‐M‐DEWMA) chart, includes two main phases. In the first phase, the PF technique is applied to estimate the unknown nonlinear states of the biological processes. In the second phase, the statistical univariate chart, MS‐M‐DEWMA is adopted to address fault detection in biological processes. Therefore, in this work, we propose a monitoring approach capable of detecting shifts in mean and/or variance in biological systems (pre‐defined structure obtained using material and energy balances) where the variables are estimated using state estimation techniques. The detection chart MS‐M‐DEWMA is applied to the residuals computed using the PF. The advantages of PF‐based MS‐M‐DEWMA method are threefold: (i) extract features and decorrelate measurements using dynamical multiscale representation; (ii) estimate the state of nonlinear biological processes using the PF technique; and (iii) enhance monitoring of biological processes through detecting shifts of both variance and mean using MS‐M‐DEWMA chart. The proposed approach is validated using a Cad system in E. coli (CSEC) model.
CFD study on Taylor bubble characteristics in Carreau‐Yasuda shear thinning liquids
Authors: Sontti Somasekhara Goud , Atta Arnab 
Published: July 2018

AbstractIn the present study, Taylor bubble formation in two‐phase gas‐non‐Newtonian Carreau liquid flowing through a confined co‐flow microchannel is investigated. Systematic analyses are carried out to explore the influences of rheological properties, inlet velocities, and surface tension on Taylor bubble length, shape, velocity, and liquid film thickness. Aqueous solutions of carboxymethyl cellulose (CMC) with different mass concentrations are considered as the non‐Newtonian liquids to understand the fundamentals of flow behaviour. With increasing solution viscosity and liquid phase inlet velocity, Taylor bubble formation frequency and velocity increased; however, the bubble length was found to decrease. Velocity profiles inside the Taylor bubble and liquid slug were analyzed, and distinct velocity distributions were found for different CMC concentrations. Flow regime maps are developed based on gas and liquid velocities for Carreau liquids in the co‐flow microchannel. This study essentially provides useful guidelines in designing a non‐Newtonian microfluidic system for precise control and manipulation of Taylor bubbles.
Numerical simulation of polymer filling process by a combined finite element/discontinuous Galerkin/level set method
Authors: Gao Puyang , Ouyang Jie , Zhou Wen 
Published: July 2018

AbstractThe filling process in injection molding involves polymer melt and air with large density/viscosity ratios and the transient free surface. It is treated as a challenging viscoelastic‐Newtonian two‐phase flow problem especially on irregular domains. In this paper, the complex filling process for the irregular cavity is simulated using a combined finite element/discontinuous Galerkin/level set method with application to the socket with five inserts, which is rarely investigated. The rheological behaviour of the viscoelastic fluid is predicted according to the eXtended Pom‐Pom (XPP) constitutive model. The level set method proposed from prior literature is utilized to capture the moving interface because of its simplicity and efficiency. The hybrid continuous and discontinuous Galerkin method is utilized to solve the viscoelastic incompressible Navier‐Stokes equations. The second order Runge Kutta discontinuous Galerkin (RKDG) method is employed to deal with the XPP constitutive equation and the level set equation due to their hyperbolic natures. This combined algorithm is convenient to cope with the irregular cavity and avoid any stabilization terms. We first investigate the filling process of the rectangular cavity without and with a diamond insert and compare with other numerical and experimental results to illustrate the validity of the coupled method. Moreover, the cavity of the socket with five inserts is considered an application case. We analyze the influences of the inlet velocity and elasticity on physical quantities such as stresses, stretch, etc. The simulation results could provide some numerical predictions for the polymer industry.
XNA Synthesis and Reverse Transcription by Engineered Thermophilic Polymerases
Authors: Cozens Christopher , Pinheiro Vitor B. 
Published: July 2018

AbstractThe B‐family polymerases of hyperthermophilic archaea have proven an exceptional platform for engineering polymerases with extended substrate spectra, despite multiple mechanisms for detecting and avoiding incorporation of non‐cognate substrates. These polymerases can efficiently synthesize and reverse‐transcribe a number of xenonucleic acids (XNAs) that differ significantly from the canonical B‐form of DNA. We present here a protocol for hexitol nucleic acid (HNA) synthesis by an engineered Thermococcus gorgonarius polymerase variant, including adaptation for large‐scale synthesis and purification, and for other XNAs. We describe XNA purification and reverse transcription (with a previously reported XNA RT also based on Thermococcus gorgonarius), as well as key considerations for the characterization and optimization of XNA reactions. © 2018 by John Wiley & Sons, Inc.
Current approaches to waste polymer utilization and minimization: a review
Authors: Okan Meltem , Aydin Halil Murat , Barsbay Murat 
Published: July 2018

AbstractThe mass production of polymer products, in particular plastics, and their widespread use depending on the inherent advantages they have, make these materials ironically a threat to life on Earth. Polymer recycling is being considered as one of the most widely accepted remedies to the threat of growing amounts of plastic waste by both the public and scientists. In practice, recycling is associated with many difficulties, such as problems related to separation, sorting and cleaning operations, lack of fiscal subsidies, instability of selective garbage separation programs, high transport and electricity costs, etc. Still, a large section of society and the authorities agree on the necessity and importance of recycling to protect the environment, and natural habitats and resources for future generations in a balanced manner to conserve raw materials, and to reduce energy consumption, municipal solid waste production and greenhouse gas emission. The recycling effort is almost endless in itself and includes a variety of approaches such as refurbishing, mechanically reshaping, chemically treating, thermally utilizing, etc. Some novel approaches such as application in carbon capture or synthesis of carbon nanostructures from the plastic waste are among the new process technologies of recycling. From traditional and promising polymer waste utilization approaches, this review will highlight sustainable methods to reduce impacts of plastic waste on the environment. © 2018 Society of Chemical Industry