bluuebunny/crossref_metadata_2025 huggingface dataset:
Nanoscale Chemical Imaging of Zeolites Using Atom Probe Tomography
Authors: Schmidt Joel E. , Peng Linqing , Poplawsky Jonathan D. , Weckhuysen Bert M.
Published: May 2018

Understanding structure–composition–property relationships in zeolite‐based materials is critical to engineering improved solid catalysts. However, this can be difficult to realize as even single zeolite crystals can exhibit heterogeneities spanning several orders of magnitude, with consequences for, for example, reactivity, diffusion as well as stability. Great progress has been made in characterizing these porous solids using tomographic techniques, though each method has an ultimate spatial resolution limitation. Atom probe tomography (APT) is the only technique so far capable of producing 3D compositional reconstructions with sub‐nanometer‐scale resolution, and has only recently been applied to zeolite‐based catalysts. Herein, we discuss the use of APT to study zeolites, including the critical aspects of sample preparation, data collection, assignment of mass spectral peaks including the predominant CO peak, the limitations of spatial resolution for the recovery of crystallographic information, and proper data analysis. All sections are illustrated with examples from recent literature, as well as previously unpublished data and analyses to demonstrate practical strategies to overcome potential pitfalls in applying APT to zeolites, thereby highlighting new insights gained from the APT method.
An Artificial Heme Enzyme for Cyclopropanation Reactions
Authors: Villarino Lara , Splan Kathryn E. , Reddem Eswar , Alonso‐Cotchico Lur , Gutiérrez de Souza Cora , Lledós Agustí , Maréchal Jean‐Didier , Thunnissen Andy‐Mark W. H. , Roelfes Gerard
Published: May 2018

An artificial heme enzyme was created through self‐assembly from hemin and the lactococcal multidrug resistance regulator (LmrR). The crystal structure shows the heme bound inside the hydrophobic pore of the protein, where it appears inaccessible for substrates. However, good catalytic activity and moderate enantioselectivity was observed in an abiological cyclopropanation reaction. We propose that the dynamic nature of the structure of the LmrR protein is key to the observed activity. This was supported by molecular dynamics simulations, which showed transient formation of opened conformations that allow the binding of substrates and the formation of pre‐catalytic structures.
Perfluoroalcohols: The Preparation and Crystal Structures of Heptafluorocyclobutanol and Hexafluorocyclobutane‐1,1‐diol
Authors: Baxter Amanda F. , Schaab Jonas , Christe Karl O. , Haiges Ralf
Published: May 2018

The first X‐ray crystal structure of an α‐fluoroalcohol is reported. Heptafluorocyclobutanol was obtained in quantitative yield from hexafluorocyclobutanone by HF addition in anhydrous hydrogen fluoride. The compound was characterized by its X‐ray single crystal structure. Heptafluorocyclobutanol readily undergoes hydrolysis to hexafluorocyclobutane‐1,1‐diol, which was also structurally characterized by X‐ray diffraction.
Enantiodivergent Synthesis of Allenes by Point‐to‐Axial Chirality Transfer
Authors: Armstrong Roly J. , Nandakumar Meganathan , Dias Rafael M. P. , Noble Adam , Myers Eddie L. , Aggarwal Varinder K.
Published: May 2018

An enantiodivergent method for the synthesis of multiply substituted allenes is described. Highly enantioenriched, point‐chiral boronic esters were synthesized by homologation of α‐seleno alkenyl boronic esters with lithiated carbamates and eliminated to form axially chiral allene products. By employing either oxidative or alkylative conditions, both syn and anti elimination could be achieved with complete stereospecificity. The process enables the synthesis of either M or P allenes from a single isomer of a point‐chiral precursor and can be employed for the enantioselective assembly of di‐, tri‐, and tetrasubstituted allenes.
Properties of Oleogels Formed With High‐Stearic Soybean Oils and Sunflower Wax
Authors: Hwang Hong‐Sik , Gillman Jason D. , Winkler‐Moser Jill K. , Kim Sanghoon , Singh Mukti , Byars Jeffrey A. , Evangelista Roque L.
Published: May 2018

In an effort to develop alternatives for harmful trans fats produced by partial hydrogenation of vegetable oils, oleogels of high‐stearic soybean (A6 and MM106) oils were prepared with sunflower wax (SW) as the oleogelator. Oleogels of high‐stearic oils did not have greater firmness when compared to regular soybean oil (SBO) at room temperature. However, the firmness of high‐stearic oil oleogels at 4 °C sharply increased due to the high content of stearic acid. High‐stearic acid SBO had more polar compounds than the regular SBO. Polar compounds in oil inversely affected the firmness of oleogels. Differential scanning calorimetry showed that wax crystals facilitated nucleation of solid fats of high‐stearic oils during cooling. Polar compounds did not affect the melting and crystallization behavior of wax. Solid fat content (SFC) showed that polar compounds in oil and wax interfered with crystallization of solid fats. Linear viscoelastic properties of 7% SW oleogels of three oils reflected well the SFC values while they did not correlate well with the firmness of oleogels. Phase‐contrast microscopy showed that the wax crystal morphology was slightly influenced by solid fats in the high‐steric SBO, A6.
Capitalist maturity and South Korea's post‐development conundrum
Authors: D'Costa Anthony P.
Published: May 2018

South Korea's post World War II economic development trajectory is well known. From an impoverished warn‐torn nation, the country has progressed on all fronts. However, the objective is to focus on the “post‐development” question, namely, what does a country do after it becomes prosperous. To put it another way, what are some of the emergent challenges that successful development poses for Korea, and how might it tackle them. I use the concept of capitalist maturity to denote Korea's current state of prosperity and examine some of the economic, social, and political consequences. Some of these post‐development conundrums I argue have resulted from the transformation of Korea's state–business development partnership to a business–state political partnership in the context of a democratizing Korea. This paper examines the challenges and some of the policy options to address them, including the rebalancing of the state–business relationship.
Insight into How Telomeric G‐Quadruplexes Enhance the Peroxidase Activity of Cellular Hemin
Authors: Ai Tingting , Yang Qiufang , Lv You , Huang Yuqin , Li Yuzhi , Geng Jia , Xiao Dan , Zhou Cuisong
Published: May 2018

The toxic oxidative damage of G‐quadruplexes (G4), linked to neurodegenerative diseases, may arise from their ability to bind and oxidatively activate cellular hemin. However, there have been no precise studies on how telomeric G4 enhances the low intrinsic peroxidase activity of hemin. Herein, a label‐free and nanopore‐based strategy was developed to explore the enhancement mechanism of peroxidase activity of hemin induced by telomeric G4 (d(TTAGGG)n). The nanopore‐based strategy demonstrated that there were simultaneously two different binding modes of telomere G4 to hemin. At the single‐molecule level, it was found that the hybrid structural telomeric G4 directly binds to hemin (the affinity constant (Ka)≈106 m−1) to form a tight complex, and some of them underwent a topological change to a parallel structure with an enhancement of Ka to approximately 107 m−1. Through detailed analysis of the topology and peroxidase activity and molecular modeling investigations, the parallel telomere G4/hemin DNAzyme structure was proven to be preferable for high peroxidase activity. Upon strong π–π stacking, the parallel structural telomere G4 supplied a key axial ligand to the hemin iron, which accelerated the intermediate compound formation with H2O2 in the catalytic cycle. Our studies developed a label‐free and single‐molecule strategy to fundamentally understand the catalytic activity and mechanism of telomeric DNAzyme, which provides some support for utilizing the toxic, oxidative‐damage property in cellular oxidative disease and anticancer therapeutics.
Pd‐Catalyzed Decarbonylative C−H Coupling of Azoles and Aromatic Esters
Authors: Matsushita Kaoru , Takise Ryosuke , Hisada Tomoya , Suzuki Shin , Isshiki Ryota , Itami Kenichiro , Muto Kei , Yamaguchi Junichiro
Published: May 2018

A decarbonylative C−H coupling of azoles and aromatic esters by palladium catalysis is described. Our previously reported Ni‐catalyzed C−H coupling of azoles and aromatic esters has a significant drawback regarding the substrate scope. Herein, we employ palladium catalysis instead of nickel, resulting in a broader substrate scope in terms of azoles and aromatic esters.
How to calculate thermostability of enzymes using a simple approach
Authors: Saqib Abdul A. N. , Siddiqui Khawar S.
Published: May 2018

Determination of thermostability of enzymes is of prime importance for their successful industrial applications and, yet, the published data has often been incompletely analyzed to assess the suitability of enzymes. It is possible to determine meaningful thermostability parameters from the routinely acquired data through a straightforward method that is not only more informative but also provides a means to compare thermostability of enzymes from different sources. Here, we describe a simple, effective, and economical way to determine enzyme thermostability. In our opinion, including this method in Biochemistry and Molecular Biology curricula will encourage students to include thermostability analysis in their future work, leading to a more meaningful approach to evaluate and compare enzymes. Furthermore, as the method requires minimum specialized equipment, the analysis will be particularly suitable for labs that cannot afford expensive setup. © 2018 by The International Union of Biochemistry and Molecular Biology, 46:398–402, 2018.
A generalized purification step for viral particles using mannitol flocculation
Authors: Heldt Caryn L. , Saksule Ashish , Joshi Pratik U. , Ghafarian Majid
Published: May 2018

Vaccine manufacturing has conventionally been performed by the developed world using traditional unit operations like filtration and chromatography. There is currently a shift in the manufacturing of vaccines to the less developed world, requiring unit operations that reduce costs, increase recovery, and are amenable to continuous manufacturing. This work demonstrates that mannitol can be used as a flocculant for an enveloped and nonenveloped virus and can purify the virus from protein contaminants after microfiltration. The recovery of the virus ranges from 58 to 96% depending on virus, the filter pore size, and the starting concentration of the virus. Protein removal of 80% was achieved for the small nonenveloped virus using a 0.1 µm filter because proteins were not flocculated with the virus and flowed through the filter. It is hypothesized that mannitol dehydrates the viral surface by controlling the water structure surrounding the virus. Without the ability to become compact, as occurs with proteins, the virus aggregates in the presence of osmolytes and proteins do not. Osmolyte flocculation is a scalable process using high flux microfilters. It has been applied to both an enveloped and nonenveloped virus, making this process friendly to a variety of vaccine and gene therapy products. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:1027–1035, 2018
Analyzing the effects of adapted flipped classroom approach on computer programming success, attitude toward programming, and programming self‐efficacy
Authors: Özyurt Hacer , Özyurt Özcan
Published: May 2018

This study analyzes the effects of the use of adapted flipped classroom approach on the programming success, attitudes, and self‐efficacy of the students in learning programming. The study was conducted in the 2016–2017 fall semester with freshman students in Introduction to Programming and Algorithm course in the Software Engineering Department of a university in Turkey. The sample of the study consists of 46 students taking this course for the first time. The quasi‐experimental research method was used in the study. One group pretest–posttest design was employed, and quantitative data were obtained from the students. The scale of attitude toward computer programming, computer programming self‐efficacy scale, computer programming success test, and practice control chart were used as data collection tools. The study results show that the use of this approach in programming learning has a positive effect on the students’ programming success and programming self‐efficacy while it does not affect their attitudes toward programming. Additionally, it is concluded that there is a highly positive relationship between the numbers of students’ fulfilling the programming tasks and their programming success. Another conclusion of the study is that there is a positive relationship at a medium level between the numbers of students’ fulfilling the programming tasks and programming self‐efficacy and their attitudes toward programming. Considering the study results as a whole, it is seen that flipped classroom approach can be adapted to teach programming.
Impact of paranasal sinus invasion on advanced nasopharyngeal carcinoma treated with intensity‐modulated radiation therapy: the validity of advanced T stage of AJCC/UICC eighth edition staging system
Authors: Wang Ying , Zhao Jie , Zhao Yajie , Yang Zhen , Lei Mingjun , Li Zhanzhan , Wei Rui , Chen Dengming , He Yuxiang , Shen Liangfang
Published: May 2018

The aim of this study was to clarify the prognostic role of paranasal sinus invasion in advanced NPC patients. Data of patients (n = 295) with advanced NPC (T3/T4N0‐3 M0) treated with intensity‐modulated radiation therapy were retrospectively analyzed. Staging was according to the AJCC/UICC eighth edition staging system. Overall survival (OS), local recurrence‐free survival (LRFS), distant metastasis‐free survival (DMFS), and disease‐free survival (DFS) were calculated, and differences were compared between patients with and without paranasal sinus invasion. Multivariate analysis was used to identify the independent predictors of different survival parameters. Paranasal sinus invasion was present in 126 of 295 (42.7%) patients. Sphenoid, ethmoid, maxillary, and frontal sinus involvements were present in 123 of 295 (41.7%), 95 of 295 (32.2%), 45 of 295 (15.3%), and 0 of 295 (0%), respectively. All survival parameters were significantly better in patients without paranasal sinus invasion. When paranasal sinus invasion was reclassified as T4 instead of T3, all survival rates, other than LRFS (P = 0.156), were significantly better in the new T3 patients, and differences in all survival parameters remained nonsignificant between T3 with paranasal sinus invasion and T4 without paranasal sinus invasion patients (all P > 0.05). In multivariate analysis, paranasal sinus invasion was found to be an independent negative prognostic factor for OS, DFS, and DMFS (P = 0.016, P = 0.004, and P = 0.006, respectively), but not for LRFS (P = 0.068). Paranasal sinus invasion has prognostic value in advanced NPC. It may be reasonable to classify paranasal sinus invasion as T4 stage.
Emotional facial expression transfer from a single image via generative adversarial nets
Authors: Qiao Fengchun , Yao Naiming , Jiao Zirui , Li Zhihao , Chen Hui , Wang Hongan
Published: May 2018

Facial expression transfer from a single image is a challenging task and has drawn sustained attention in the fields of computer vision and computer graphics. Recently, generative adversarial nets (GANs) have provided a new approach to facial expression transfer from a single image toward target facial expressions. However, it is still difficult to obtain a sequence of smoothly changed facial expressions. We present a novel GAN‐based method for generating emotional facial expression animations given a single image and several facial landmarks for the in‐between stages. In particular, landmarks of other subjects are incorporated into a GAN model to control the generated facial expression from a latent space. With the trained model, high‐quality face images and a smoothly changed facial expression sequence can be effectively obtained, which are showed qualitatively and quantitatively in our experiments on the Multi‐PIE and CK+ data sets.
Sketch‐based shape‐preserving tree animations
Authors: Wang Yutong , Wang Luyuan , Deng Zhigang , Jin Xiaogang
Published: May 2018

We present a novel and intuitive sketch‐based tree animation technique, targeting on generating a new type of special effect of smoothly transforming leafy trees into morphologically different new shapes. Both topological consistencies of branches and meaningful in‐between crown shapes are preserved during the transformation. Specifically, it takes a leafy tree and a user's sketch describing the silhouette of the desired crown shape under a certain viewpoint as the input. Based on a self‐adaptive multiscale cage tree representation, branches are locally transformed through a series of topology‐aware deformations, and the resulting tree conforms to the user‐designed shape, demonstrating better aesthetics compared to global single‐cage‐based methods. By interpolating the transformations, we are able to create visually pleasing shape‐preserving animations of trees transforming between two crown shapes. Our proposed framework also provides an efficient way to interactively edit leafy trees toward desired shapes, demonstrating its potential to leverage existing tree modeling frameworks by providing flexible and intuitive tree editing operations.
Distributed coordination with connectivity maintenance for nonholonomic robots
Authors: Huang Wanrong , Wang Yanzhen , Yi Xiaodong , Yang Xue‐Jun
Published: May 2018

Multirobot systems have been studied extensively in the recent years. Maintaining connectivity has significant impacts on the stability and convergence of the multirobot systems. In this work, we design a three‐layer framework for multirobot coordination. Furthermore, a novel distributed algorithm is proposed to achieve the navigation objective while satisfying connectivity maintenance and collision avoidance constraints. The algorithm is a hybrid of an rapidly exploring random tree‐based planner and an extended distributed navigation function‐based controller. The coordination framework and the distributed algorithm are demonstrated to be effective through a series of illustrative simulations. They outperform the current state‐of‐the‐art method in terms of efficiency and applicability.
Example‐based synthesis for sound of ocean waves caused by bubble dynamics
Authors: Wang Kai , Liu Shiguang
Published: May 2018

We present an automatic approach for the semantic modeling of indoor scenes based on a single photograph, instead of relying on depth sensors. Without using handcrafted features, we guide indoor scene modeling with feature maps extracted by fully convolutional networks. Three parallel fully convolutional networks are adopted to generate object instance masks, a depth map, and an edge map of the room layout. Based on these high‐level features, support relationships between indoor objects can be efficiently inferred in a data‐driven manner. Constrained by the support context, a global‐to‐local model matching strategy is followed to retrieve the whole indoor scene. We demonstrate that the proposed method can efficiently retrieve indoor objects including situations where the objects are badly occluded. This approach enables efficient semantic‐based scene editing.
Sawtooth cycle revisited
Authors: Tsuruga Junki , Iwasaki Kei
Published: May 2018

Solving the pressure Poisson equation dominates a large portion of computational time for incompressible fluid flow simulations. To solve the pressure Poisson equation efficiently, geometric multigrid methods are used directly or used as the preconditioner for the conjugate gradient (CG) method. Conventionally, the V‐cycle multigrid method is widely employed, and little attention has been paid to other cycles. In this paper, we introduce the sawtooth cycle multigrid method and its simple extension called N‐cycle, which provides better convergence in equal time comparison with the V‐cycle as a direct solver of the pressure Poisson equation. We also apply the N‐cycle to the preconditioner of the CG method and show that the N‐cycle multigrid CG method can provide better convergence than the V‐cycle multigrid CG method.
Insights into the Sorption Mechanisms of Cr(III) by Chemically Modified Pine Bark
Authors: Arim Aline L. , Quina Margarida J. , Gando-Ferreira Licínio M.
Published: May 2018

The mechanisms of Cr(III) sorption by pine bark treated chemically (MPB) with NaOH were investigated. The removal of Cr(III) was found to be strongly dependent on the initial pH. Thus, a model was developed for describing the adsorption as a function of this variable. The removal efficiencies as a function of the adsorbent dosage for different pH values were predicted. The equilibrium data were well fitted by the modified Langmuir isotherm. Ion exchange at equilibrium suggested chromium uptake and Ca2+ release occurs approximately according to the stoichiometry of the equilibrium reactions. Cr(III) desorption from MPB with chelating agents was not very effective while high efficiencies were achieved with HNO3 solutions.
Cu3P/CuO Core‐Shell Nanorod Arrays as High‐Performance Electrocatalysts for Water Oxidation
Authors: Du Jian , Li Fei , Wang Yong , Zhu Yong , Sun Licheng
Published: May 2018

Earth‐abundant transition‐metal‐based oxides are potential candidates to replace the state‐of‐the‐art noble‐metal‐based oxygen evolution catalysts (OECs) such as IrO2 and RuO2. Despite the low cost and large abundance, copper‐based OER catalysts have been less frequently studied, mainly owing to the low electrical conductivity of copper oxides that results in large overpotential and sluggish kinetics for oxygen evolution. We report here the in situ fabrication of semi‐metallic Cu3P nanorod arrays on commercial copper foam via a template approach; the resulting self‐supported core‐shell Cu−Cu3P/CuO electrode has the merits of high electrical conductivity, large active area, and short diffusion paths for electrolyte and evolved oxygen, exhibiting a low overpotential of 315 mV and high durability over 50 h at a current density of 10 mA cm−2 for OER in 1.0 M KOH. The remarkable OER performance reported here is not only superior to that of analogous Cu−CuO foam electrode, but also outperforms those of copper‐based OER electrocatalysts in the literature.
Searching for Models Exhibiting High Circularly Polarized Luminescence: Electroactive Inherently Chiral Oligothiophenes
Authors: Benincori Tiziana , Appoloni Giulio , Mussini Patricia Romana , Arnaboldi Serena , Cirilli Roberto , Quartapelle Procopio Elsa , Panigati Monica , Abbate Sergio , Mazzeo Giuseppe , Longhi Giovanna
Published: May 2018

Two new inherently chiral oligothiophenes characterized by the atropisomeric 3,3′‐bithianaphtene scaffold functionalized with fused ring bithiophene derivatives, namely 4H‐cyclopenta[2,1‐b3:4b′]dithiophene (CPDT) and dithieno[3,3‐b:2′,3′‐d]pyrrole (DTP), were synthesized. The racemates were fully characterized and resolved into antipodes by enantioselective HPLC. The enantiomers were analyzed through different chiroptical techniques: electronic circular dichroism (ECD) and vibrational circular dichroism (VCD) were employed to attribute the absolute configuration (AC). Comparison of experimental and calculated VCD spectra confirmed the DFT calculated conformational characteristics. The compound functionalized with two CPDT units was oxidized with FeCl3, and ECD and CPL of the resulting material were measured. Circularly polarized luminescence (CPL) was measured to verify if inherently chiral oligothiophenes could be promising systems for chiral photonics applications.
A Theoretical Outlook on the Stereoselectivity Origins of Isoselective Zirconocene Propylene Polymerization Catalysts
Authors: Castro Ludovic , Therukauff Gabriel , Vantomme Aurelien , Welle Alexandre , Haspeslagh Luc , Brusson Jean‐Michel , Maron Laurent , Carpentier Jean‐François , Kirillov Evgueni
Published: May 2018

The first three insertion steps of propylene for isoselective metallocenes from the one‐carbon‐bridged cyclopentadienyl–fluorenyl {Cp/Flu} and silicon‐bridged ansa‐bis(indenyl) {SBI} families were computed by using a theoretical method implementing the B3PW91 functional in combination with solvent corrections incorporated with the Solvation Model based on Density (SMD) continuum model. For C1‐symmetric {Cp/Flu}‐type metallocenes, two mechanisms of stereocontrol were validated theoretically: more facile and more stereoselective chain “stationary” insertion (or site epimerization backskip) and less stereoselective alternating mechanisms. For the C2‐symmetric {SBI}‐type system, the computation results were in complete agreement with the sole operating chain migratory insertion mechanism. The thermochemical data obtained through the study were used to predict microstructures of polypropylenes by using three‐parameter and one‐parameter statistical models for the two metallocene systems, respectively. The calculated meso/rac pentad distributions were found to be in good agreement with those determined experimentally for isotactic polypropylene samples obtained at different polymerization temperatures.
Late‐Stage Functionalization of Arylacetic Acids by Photoredox‐Catalyzed Decarboxylative Carbon–Heteroatom Bond Formation
Authors: Sakakibara Yota , Ito Eri , Fukushima Tomohiro , Murakami Kei , Itami Kenichiro
Published: May 2018

The rapid transformation of pharmaceuticals and agrochemicals enables access to unexplored chemical space and thus has accelerated the discovery of novel bioactive molecules. Because arylacetic acids are regarded as key structures in bioactive compounds, new transformations of these structures could contribute to drug/agrochemical discovery and chemical biology. This work reports carbon–nitrogen and carbon–oxygen bond formation through the photoredox‐catalyzed decarboxylation of arylacetic acids. The reaction shows good functional group compatibility without pre‐activation of the nitrogen‐ or oxygen‐based coupling partners. Under similar reaction conditions, carbon–chlorine bond formation was also feasible. This efficient derivatization of arylacetic acids makes it possible to synthesize pharmaceutical analogues and bioconjugates of pharmaceuticals and natural products.
Clinical trial cytology: Use of on‐site evaluation of small biopsy and FNA samples for clinical trials and biomarker research studies
Authors: Manzo Julia L. , Cuda Jackie , Pantanowitz Liron , Xing Juan , Yu Jing , Beasley H. Scott , Dhir Rajiv , Monaco Sara E.
Published: May 2018

BACKGROUND

After increased requests for biopsies for clinical trials and biomarker research, the University of Pittsburgh Medical Center created a clinical trial research service that partnered pathology, radiology, and medicine to facilitate rapid on‐site evaluation (ROSE) of fine‐needle aspiration (FNA) and/or core needle biopsy (CNB) samples to confirm the presence of tumor in these studies.

METHODS

Clinical trial coordinators organized biopsies for patients needing tumor samples for trials, and informed the cytopathology and radiology team. ROSE was performed to confirm the presence of sufficient tumor in FNA specimens and/or touch preparations of CNB.

RESULTS

A total of 79 cases from a total of 14 clinical trials were evaluated with ROSE, 77 of which (97%) were for research only. There were 53 cases (67%) from breast/ovarian cancer studies that were initiated between 2008 and 2009, whereas 26 cases (33%) included a variety of other tumors for studies that were started between 2011 and 2014. The majority required CNB samples (60 cases; 76%), 20% of which used an FNA for needle placement before obtaining CNB material and 56% of which had touch preparations of the CNB evaluated without a preceding FNA. The concordance rate for ROSE with final adequacy of the sample was 96% to 100%.

CONCLUSIONS

The study institution has experienced an increase in the number of clinical trial studies requesting ROSE to confirm the presence of tumor in a variety of malignancies. Cytology laboratories can help with patient care by offering ROSE to determine the adequacy of clinical trial material to minimize the submission of unsatisfactory or nonrepresentative material. Developing a clinical research service enhances communication and the processing of novel research specimens for cancer patients. Cancer Cytopathol 2018. © 2018 American Cancer Society.
The Oxidation of Peroxide by Disordered Metal Oxides: A Measurement of Thermodynamic Stability “By Proxy”
Authors: Sabri Mayada , King Hannah J. , Gummow Rosalind J. , Malherbe François , Hocking Rosalie K.
Published: May 2018

It is often noted that disordered materials have different chemical properties to their more “ordered” cousins. Quantifying these effects in terms of thermodynamics is challenging in part because disordered materials can be difficult to characterise and are frequently relatively unstable. During the course of our experiments to understand the effects of disorder in catalysts for water oxidation we observed that many disordered manganese and cobalt oxide water oxidation catalysts directly oxidised peroxide in contrast to their more ordered analogues which catalysed its disproportionation, that is, MnO2+2 H++H2O2→Mn2++2 H2O+O2 (oxidation) versus H2O2→H2O+
 O2 (disproportionation). By measuring the efficiency for one reaction over the other as a function of pH, we were able to quantify the relative stability of materials in two series of metal oxides and thereby quantify their relative thermodynamic stability, “by proxy”. We found that for the series of catalysts investigated the disorder made the materials stronger chemical oxidants and worse catalysts for the disproportionation of peroxide.
The value relevance of banking sector multidimensional corporate sustainability performance
Authors: Aras Guler , Tezcan Nuray , Kutlu Furtuna Ozlem
Published: May 2018

The purpose of this paper is to evaluate Turkish banks' multidimensional corporate sustainability performance and whether banks' sustainability efforts are value related. Both qualitative and quantitative data analysis, namely content analysis, entropy based and TOPSIS techniques, have been utilized in order to measure the sustainability performance. The Spearman rank correlation coefficient has been employed to investigate the nexus between overall sustainability performance scores of the banks and market value during the years 2013 and 2015. The results of this study are insignificant in the ongoing debate on whether Turkish banks' sustainability efforts are value related. However, a significant and positive relationship has been found between the financial sustainability performance and the market value in the long run. Additionally, a multidimensional corporate sustainability model that has the five dimensions of economic, environmental, social, governance and financial disclosures has been proposed. This paper is among the first to explore the nexus between sustainability performance and market value in Turkey.
Organizational structure, slack resources and sustainable corporate socially responsible performance
Authors: Zhang Ying , Li Ji , Jiang Wanxing , Zhang Haomin , Hu Yanghong , Liu Min
Published: May 2018

The current research on the slack–performance relationship pays attention mainly to a set of overlapping slack natures, such as being sticky or absorbed, without sufficient consideration of variables related to the internal structure of a given organization. We posit that this weakness may prevent us from further understanding how different slack resources (the slacks) influence firms' corporate socially responsible performance (CSR). Combining the resource‐based view of the firm with a perspective of international integration, we propose a new model explaining how structural‐related variables may interact with the slacks and influence firms' CSR. Analyzing data from publicly listed US firms (2002–2012), we obtain evidence supporting the importance of organizational integration structure for understanding the slack–performance relationship.
Increased network routing efficiency through coordinated Fibbing
Authors: Zhang Weifan , Zhang Dong , Zhu Danhong
Published: May 2018

For finding the best route in a network, distributed routing offers robustness but has poor flexibility while central control of software‐defined networking is just the opposite. The Fibbing architecture can run distributed routing protocols on software‐defined networking and has both robustness and flexibility. The 2 main steps of Fibbing's process are (1) compute a route that is available for the network according to the network topology and the flow request and (2) add fake nodes and fake links to augment the network topology in conformity with the distributed routing protocol and the route computed in the first step. Both of the 2 steps affect the performance of the network, but Fibbing does not consider them coordinately, and the cost of choosing the routes can be reduced further. In this paper, a coordinated algorithm for Fibbing is proposed to determine a lowest‐cost route. In the process to calculate an available route, our algorithm accommodates not only the network topology and the flow request but also the fake nodes and the fake links. The experiments on random topologies and classic topologies show that our algorithm can reduce the numbers of the fake nodes and the costs of the chosen routes, with the improved flow request acceptance ratios achieved.
Novel primary amine diazeniumdiolates—Chemical and biological characterization
Authors: Puglisi Melany P. , Bradaric Michael J. , Pontikis John , Cabai Jonathan , Weyna Theodore , Tednes Patrick , Schretzman Robert , Rickert Karl , Cao Zhao , Andrei Daniela
Published: May 2018

Hit, Lead & Candidate Discovery

Diazeniumdiolates, also known as NONOates, are extensively used in biochemical, physiological, and pharmacological studies due to their ability to release nitric oxide (NO.) and/or their congeneric nitroxyl (HNO). The purpose of this work was to synthesize a series of primary amine‐based diazeniumdiolates as HNO/NO donors and to determine their efficacy as anticancer and antifungal agents in vivo. The seven compounds (3a‐3g) were successfully synthesized and characterized, one of which had been previously reported in the literature (3g). Two compounds showed anti‐proliferative effects against ovarian (ES2 and SKOV3) and AML monocyte‐derived cancer cells (THP‐1) when tested with standard MTT assays. Compounds 3a and 3g demonstrated reduced ovarian cancer cell proliferation when treated at doses from 0.033 to 1.0 mg/mL at the 24 hr time point. These compounds also exhibited moderate and selective antifungal activity against Fusarium oxysporum f.sp. lycopersici, one cause of opportunistic infections of immunocompromised patients, inhibiting the growth of the fungi at LD50 at 10 mg/mL. A third compound (3e) did not exhibit similar activities, possibly due to the alkyl chain. Our results suggest that the primary amine diazeniumdiolates may offer a versatile platform for the development of HNO/NO donors for biomedical applications.
Influence of invasion history on rapid morphological divergence across island populations of an exotic bird
Authors: Valentin Rafael E. , Lockwood Julie L. , Mathys Blake A. , Fonseca Dina M.
Published: May 2018

There is increasing evidence that exotic populations may rapidly differentiate from those in their native range and that differences also arise among populations within the exotic range. Using morphological and DNA‐based analyses, we document the extent of trait divergence among native North American and exotic Hawaiian populations of northern cardinal (Cardinalis cardinalis). Furthermore, using a combination of historical records and DNA‐based analyses, we evaluate the role of founder effects in producing observed trait differences. We measured and compared key morphological traits across northern cardinal populations in the native and exotic ranges to assess whether trait divergence across the Hawaiian Islands, where this species was introduced between 1929 and 1931, reflected observed variation across native phylogeographic clades in its native North America. We used and added to prior phylogenetic analyses based on a mitochondrial locus to identify the most likely native source clade(s) for the Hawaiian cardinal populations. We then used Approximate Bayesian Computation (ABC) to evaluate the role of founder effects in producing the observed differences in body size and bill morphology across native and exotic populations. We found cardinal populations on the Hawaiian Islands had morphological traits that diverged substantially across islands and overlapped the trait space of all measured native North American clades. The phylogeographic analysis identified the eastern North American clade (C. cardinalis cardinalis) as the most likely and sole native source for all the Hawaiian cardinal populations. The ABC analyses supported written accounts of the cardinal's introduction that indicate the original 300 cardinals shipped to Hawaii were simultaneously and evenly released across Hawaii, Kauai, and Oahu. Populations on each island likely experienced bottlenecks followed by expansion, with cardinals from the island of Hawaii eventually colonizing Maui unaided. Overall, our results suggest that founder effects had limited impact on morphological trait divergence of exotic cardinal populations in the Hawaiian archipelago, which instead reflect postintroduction events.
Reindeer green‐wave surfing constrained by predators
Authors: Rivrud Inger Maren , Sivertsen Therese Ramberg , Mysterud Atle , Åhman Birgitta , Støen Ole‐Gunnar , Skarin Anna
Published: May 2018

Migratory large herbivores in seasonal environments are known to follow the onset of new growth during spring, so‐called green‐wave surfing. This ensures prolonged access to forage with an optimal balance between forage quality and quantity. Many studies have focused on herbivores’ ability to follow the spring flush, but without considering potential constraints to surfing the green wave. The presence of predators is likely to be such a limitation, which could force herbivores to deviate from the optimal movement patterns in terms of forage access. We compared how well 319 reindeer (Rangifer tarandus) from seven different populations followed the green‐up at different population densities of brown bear (Ursus arctos). We found that reindeer at higher bear densities selected movement paths with lower access to high‐quality forage and deviated more in time from following the peak of the green wave, thus missing out on valuable forage. In addition, reindeer generally moved faster at higher bear densities, but this pattern was more consistent in forest habitats. Our results indicate that reindeer are forced to deviate from following the spring flush and alter their movement pattern in areas with high bear densities, which may lead to reduced body condition for reindeer experiencing high predation risk. With the recent recolonization of large carnivores in northern ecosystems, it is critical to understand the direct and indirect effects of predators on large herbivores in order to assess effects on population dynamics and potentially cascading consequences on ecosystem function.
Serotonin decreases the production of Th1/Th17 cytokines and elevates the frequency of regulatory CD4+ T‐cell subsets in multiple sclerosis patients
Authors: Sacramento Priscila M. , Monteiro Clarice , Dias Aleida S. O. , Kasahara Taissa M. , Ferreira Thaís B. , Hygino Joana , Wing Ana Cristina , Andrade Regis M. , Rueda Fernanda , Sales Marisa C. , Vasconcelos Claudia Cristina , Bento Cleonice A. M.
Published: May 2018

Excessive levels of proinflammatory cytokines in the CNS are associated with reduced serotonin (5‐HT) synthesis, a neurotransmitter with diverse immune effects. In this study, we evaluated the ability of exogenous 5‐HT to modulate the T‐cell behavior of patients with MS, a demyelinating autoimmune disease mediated by Th1 and Th17 cytokines. Here, 5‐HT attenuated, in vitro, T‐cell proliferation and Th1 and Th17 cytokines production in cell cultures from MS patients. Additionally, 5‐HT reduced IFN‐γ and IL‐17 release by CD8+ T cells. By contrast, 5‐HT increased IL‐10 production by CD4+ T cells from MS patients. A more accurate analysis of these IL‐10‐secreting CD4+ T cells revealed that 5‐HT favors the expansion of FoxP3+CD39+ regulatory T cells (Tregs) and type 1 regulatory T cells. Notably, this neurotransmitter also elevated the frequency of Treg17 cells, a novel regulatory T‐cell subset. The effect of 5‐HT in upregulating CD39+ Treg and Treg17 cells was inversely correlated with the number of active brain lesions. Finally, in addition to directly reducing cytokine production by purified Th1 and Th17 cells, 5‐HT enhanced in vitro Treg function. In summary, our data suggest that serotonin may play a protective role in the pathogenesis of MS.
Kinetic‐Mechanistic and Solid‐State Study of the Oxidative Addition and Migratory Insertion of Iodomethane to [Rhodium(S,O‐BdiPT or N,O‐ox)(CO)(PR1R2R3)] Complexes
Authors: Warsink Stefan , Riekert Kotze P. D. , Janse van Rensburg J. M. (Inus) , Venter Johan A. , Otto Stefanus , Botha Ebrahiem , Roodt Andreas
Published: May 2018

Rhodium(I) carbonyl complexes containing bidentate X,O‐Bid [S,O‐BdiPT or N,O‐ox; S,O‐BdiPTH = N‐benzoyl‐N′,N′‐(diphenyl)thiourea; N,O‐oxH = 8‐hydroxyquinoline] ligands of the form [Rh(X,O‐Bid)(CO)(PR1R2R3)] (R1, R2, R3 = Ph or Cy) bearing different phosphine ligands, were investigated, the structural characterization of four example complexes is described and an extensive spectroscopic kinetic‐mechanistic study of the oxidative addition of iodomethane thereto is discussed. Reaction with iodomethane led to RhIII‐acyl species as secondary (final) products, whereas the primary RhIII‐alkyl complexes, although rapidly formed, were only observed as intermediates, in small quantities for S,O‐BdiPT (large S–Rh–O bite angle of 90–91°) but in significant amounts for N,O‐ox complexes (less steric with a smaller N–Rh–O bite angle of 79–80°). Overall, almost an order‐of‐magnitude difference in rate constants was observed for the S,O‐BdiPT complexes, with the PPh2Cy‐ and PPhCy2‐bearing complexes showing the largest variation. In both the S,O‐BdiPT and N,O‐ox ligand systems an associative activation is inferred from the large negative ΔS≠ values. The relative reactivity of RhI‐X,O‐Bid complexes, where X = O, S or N, follows a surprising similar reactivity relationship when stepwise varying the PPh3, PPh2Cy, PPhCy2 and PCy3 tertiary phosphine ligands, suggesting a systematic behavior by the PR3 ligands, independent of the X,O‐Bid ligand at the RhI metal center.
Tuning the Structure of Phosphahelicenes for Targeted Applications in Enantioselective Phosphine Organocatalysis
Authors: Aillard Paul , Gicquel Maxime , Yavari Keihann , Retailleau Pascal , Voituriez Arnaud , Marinetti Angela
Published: May 2018

The use of phosphahelicenes as nucleophilic organocatalysts for [3+2] cyclization reactions between allenoates and 2‐benzylidenemalononitriles has been extended by the systematic screening of phosphines with different helical scaffolds and substitution patterns. Among others, a new series of phosphahelicenes have been prepared by bromination/Suzuki coupling reactions of a pre‐formed phosphahelicene. This late bromination approach represents a suitable strategy for accessing a broad variety of substituted phosphahelicenes from a single intermediate. It represents a powerful tool for the catalysis‐oriented optimization of their structural features.
Optimization of an Electrochemical Sensor for Determination of Imidacloprid Based on β‐cyclodextrin Electropolymerization on Glassy Carbon Electrode
Authors: Oliveira Ana Elisa Ferreira , Bettio Guilherme Braga , Pereira Arnaldo César
Published: May 2018

An electrochemical sensor based on electropolymerization of β‐cyclodextrin (β‐CD) on a glassy carbon electrode (GCE) was developed for the determination of imidacloprid (IMP). That insecticide is the most commonly used insecticides globally and has been related to the death of bee colonies around the world are imperative. So the development of a simple, cheap and sensitive method for IMP determination is essential. This work aims the modification of a GCE by β‐CD film. The analytical response obtained with GCCE/β‐CD in the presence of the IMP showed an increase in the peak current variation of 947 % in relation to the bare GCE, indicating that the analyte was encapsulated in the β‐CD increasing the detection sensitivity. The followed experimental conditions were optimized: potential range (−1.3 to 0.9 V), presence or absence of dissolved oxygen (presence) and stirring during the electropolymerization (with agitation), number of cycles (5 scans), electrolyte pH (pH=5.0), scan rate (100 mV s−1) and concentration of β‐CD (6 mol L−1). The optimization promoted a peak current variation increase of 57 %, developing a more sensitivity methodology.
Comparative study of mefloquine and sulphadoxine–pyrimethamine for malaria prevention among pregnant women with HIV in southwest Nigeria
Authors: Akinyotu Oriyomi , Bello Folasade , Abdus‐Salam Rukiyat , Arowojolu Ayodele
Published: May 2018

Objective

To compare the effectiveness of mefloquine and sulphadoxine–pyrimethamine as intermittent preventive therapy for malaria among pregnant women with HIV.

Methods

The present randomized, controlled, prospective, open‐label study enrolled women with HIV who had reached at least 16 weeks of pregnancy attending prenatal clinics at secondary and tertiary health facilities in South West Nigeria between January 1 and August 31, 2016. Block randomization was used to assign patients to treatment with mefloquine or sulphadoxine–pyrimethamine for malaria prophylaxis. The primary outcome was malaria parasitemia at delivery. Data were compared with the χ2 and t tests on a per‐protocol basis.

Results

Of 142 women enrolled and randomized equally to each group, 131 (92.3%) completed the study (64 in the mefloquine group and 67 in the sulphadoxine‐pyrimethamine group). Blood‐sample malaria parasites were isolated from 6 (9%) and 5 (7%) patients in the mefloquine and sulphadoxine–pyrimethamine groups, respectively, at enrolment, and 6 (9%) and 9 (13%) patients in the mefloquine and sulphadoxine–pyrimethamine groups, respectively, at delivery; the differences between the groups was not significant at enrolment (P=0.693) or delivery (P=0.466).

Conclusion

Outcomes following prophylactic use of mefloquine for intermittent preventive therapy for malaria among pregnant women with HIV were comparable to sulphadoxine–pyrimethamine treatment; mefloquine is a feasible alternative therapy.

ClinicalTrials.gov: NCT02524444.
H3PW12O40@nano‐ZnO: An efficient, recyclable, and eco‐friendly catalyst for the green synthesis of novel benzo[a]pyrimido[5′,4′:5,6]pyrano[2,3‐c]phenazines via sequential multicomponent reactions under microwave irradiation
Authors: Mohammadrezaei Maryam , Mohebat Razieh , Tabatabaee Masoumeh
Published: May 2018

A simple, efficient, single‐pot synthesis of novel heteroaryl‐substituted benzo[a]pyrimido[5′,4′:5,6]pyrano[2,3‐c]phenazines has been developed via initial Knoevenagel, subsequent Michael, and final heterocyclization reactions of 2‐hydroxynaphthalene‐1,4‐dione, o‐phenylenediamine, aromatic aldehydes, and barbituric acid in the presence of H3PW12O40@nano‐ZnO as a recyclable heterogeneous catalyst in EtOH under microwave irradiation (MWI). This sequential green process with several advantages, such as operational simplicity, high yield, low cost, easy handling, eco‐friendliness and reusability of the catalyst, absence of any tedious work‐up or purification, and avoidance of hazardous or toxic reagents/catalysts/solvents, opens an effective and convenient way to pyrano‐functionalized benzophenazine systems, which are promising compounds for different biomedical applications.