bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development and validation of a septoplasty training model using 3‐dimensional printing technology
Authors: AlReefi Mahmoud A. , Nguyen Lily H.P. , Mongeau Luc G. , Haq Bassam ul , Boyanapalli Siddharth , Hafeez Nauman , Cegarra‐Escolano Francois , Tewfik Marc A. 
Published: November 2016

BackgroundProviding alternative training modalities may improve trainees’ ability to perform septoplasty. Three‐dimensional printing has been shown to be a powerful tool in surgical training. The objectives of this study were to explain the development of our 3‐dimensional (3D) printed septoplasty training model, to assess its face and content validity, and to present evidence supporting its ability to distinguish between levels of surgical proficiency.MethodsImaging data of a patient with a nasal septal deviation was selected for printing. Printing materials reproducing the mechanical properties of human tissues were selected based on literature review and prototype testing. Eight expert rhinologists, 6 senior residents, and 6 junior residents performed endoscopic septoplasties on the model and completed a postsimulation survey. Performance metrics in quality (final product analysis), efficiency (time), and safety (eg, perforation length, nares damage) were recorded and analyzed in a study‐blind manner.ResultsThe model was judged to be anatomically correct and the steps performed realistic, with scores of 4.05 ± 0.82 and 4.2 ± 1, respectively, on a 5‐point Likert scale. Ninety‐two percent of residents desired the simulator to be integrated into their teaching curriculum. There was a significant difference (p < 0.05) between the expert, intermediate, and novice groups in time taken and nares cuts, whereas other performance metrics showed no significant difference.ConclusionTo our knowledge, there are no other simulator training models for septoplasty. Our model incorporates 2 different materials mixed into the 3 relevant consistencies necessary to simulate septoplasty. Our findings provide evidence supporting the validity of the model.
Copper‐Catalyzed Bromination of C(sp3)−H Bonds Distal to Functional Groups
Authors: Liu Tao , Myers Michael C. , Yu Jin‐Quan 
Published: November 2016

AbstractSelective bromination of γ‐methylene C(sp3)−H bonds of aliphatic amides and δ‐methylene C(sp3)−H bonds of nosyl‐protected alkyl amines are developed using NBS as the brominating reagent and catalytic amount of CuII/phenanthroline complexes as the catalyst. Aryl and benzylic C−H bonds at other locations remain intact during this directed radical abstraction reaction.
Unambiguous Determination of Protein Arginine Ionization States in Solution by NMR Spectroscopy
Authors: Yoshimura Yuichi , Oktaviani Nur Alia , Yonezawa Kento , Kamikubo Hironari , Mulder Frans A. A. 
Published: November 2016

AbstractBecause arginine residues in proteins are expected to be in their protonated form almost without exception, reports demonstrating that a protein arginine residue is charge‐neutral are rare and potentially controversial. Herein, we present a 13C‐detected NMR experiment for probing individual arginine residues in proteins notwithstanding the presence of chemical and conformational exchange effects. In the experiment, the 15Nη and 15Nϵ chemical shifts of an arginine head group are correlated with that of the directly attached 13Cζ. In the resulting spectrum, the number of protons in the arginine head group can be obtained directly from the 15N–1H scalar coupling splitting pattern. We applied this method to unambiguously determine the ionization state of the R52 side chain in the photoactive yellow protein from Halorhodospira halophila. Although only three Hη atoms were previously identified by neutron crystallography, we show that R52 is predominantly protonated in solution.
Efficient Overall Water‐Splitting Electrocatalysis Using Lepidocrocite VOOH Hollow Nanospheres
Authors: Shi Huanhuan , Liang Hanfeng , Ming Fangwang , Wang Zhoucheng 
Published: November 2016

AbstractHerein we report the control synthesis of lepidocrocite VOOH hollow nanospheres and further their applications in electrocatalytic water splitting for the first time. By tuning the surface area of the nanospheres, the optimal performance can be achieved with low overpotentials of 270 mV for the oxygen evolution reaction (OER) and 164 mV for the hydrogen evolution reaction (HER) at 10 mA cm−2 in 1 m KOH, respectively. Furthermore, when used as both the anode and cathode for overall water splitting, a low cell voltage of 1.62 V is required to reach the current density of 10 mA cm−2, making the VOOH hollow nanospheres an efficient alternative to water splitting.
Discrete Silver(I)‐Palladium(II)‐Oxo Nanoclusters, {Ag4Pd13} and {Ag5Pd15}, and the Role of Metal–Metal Bonding Induced by Cation Confinement
Authors: Yang Peng , Xiang Yixian , Lin Zhengguo , Lang Zhongling , Jiménez‐Lozano Pablo , Carbó Jorge J. , Poblet Josep M. , Fan Linyuan , Hu Changwen , Kortz Ulrich 
Published: November 2016

AbstractWe introduce the class of discrete silver(I)‐palladium(II)‐oxo nanoclusters with the preparation of {Ag4Pd13} and {Ag5Pd15}. Both polyanions represent the first examples of noble metal‐capped polyoxo‐noble‐metalates in a fully inorganic assembly, featuring an unprecedented host–guest mode containing hetero‐ and homometallic Ag–Pd and Ag–Ag bonding interactions. Comprehensive theoretical calculations suggest that the Ag–Pd metallic bonds originate partially from surface confinement of AgIguest ions onto the anionic polyoxopalladate host that is induced by strong electrostatic forces. This work opens the field of fully inorganic silver‐palladium‐oxo nanoclusters, which can be considered as discrete mixed noble metal precursors for the formation of monodisperse core–shell nanoparticles, with high relevance for catalysis.
Profiling Functional and Biochemical Phenotypes of Circulating Tumor Cells Using a Two‐Dimensional Sorting Device
Authors: Poudineh Mahla , Labib Mahmoud , Ahmed Sharif , Nguyen L. N. Matthew , Kermanshah Leyla , Mohamadi Reza M. , Sargent Edward H. , Kelley Shana O. 
Published: November 2016

AbstractDuring cancer progression, tumors shed circulating tumor cells (CTCs) into the bloodstream. CTCs that originate from the same primary tumor can have heterogeneous phenotypes and, while some CTCs possess benign properties, others have high metastatic potential. Deconstructing the heterogeneity of CTCs is challenging and new methods are needed that can sort small numbers of cancer cells according to their phenotypic properties. Here we describe a new microfluidic approach that profiles, along two independent phenotypic axes, the behavior of heterogeneous cell subpopulations. Cancer cells are first profiled according to expression of a surface marker using a nanoparticle‐enabled approach. Along the second dimension, these subsets are further separated into subpopulations corresponding to migration profiles generated in response to a chemotactic agent. We deploy this new technique and find a strong correlation between the surface expression and migration potential of CTCs present in blood from mice with xenografted tumors. This system provides an important new means to characterize functional diversity in circulating tumor cells.
Gating of Quantum Interference in Molecular Junctions by Heteroatom Substitution
Authors: Liu Xunshan , Sangtarash Sara , Reber David , Zhang Dan , Sadeghi Hatef , Shi Jia , Xiao Zong‐Yuan , Hong Wenjing , Lambert Colin J. , Liu Shi‐Xia 
Published: November 2016

AbstractTo guide the choice of future synthetic targets for single‐molecule electronics, qualitative design rules are needed, which describe the effect of modifying chemical structure. Here the effect of heteroatom substitution on destructive quantum interference (QI) in single‐molecule junctions is, for the first time experimentally addressed by investigating the conductance change when a “parent” meta‐phenylene ethylene‐type oligomer (m‐OPE) is modified to yield a “daughter” by inserting one nitrogen atom into the m‐OPE core. We find that if the substituted nitrogen is in a meta position relative to both acetylene linkers, the daughter conductance remains as low as the parent. However, if the substituted nitrogen is in an ortho position relative to one acetylene linker and a para position relative to the other, destructive QI is alleviated and the daughter conductance is high. This behavior contrasts with that of a para‐connected parent, whose conductance is unaffected by heteroatom substitution. These experimental findings are rationalized by transport calculations and also agree with recent “magic ratio rules”, which capture the role of connectivity in determining the electrical conductance of such parents and daughters.
BCl3‐Induced Annulative Oxo‐ and Thioboration for the Formation of C3‐Borylated Benzofurans and Benzothiophenes
Authors: Warner Andrew J. , Churn Anna , McGough John S. , Ingleson Michael J. 
Published: November 2016

AbstractBCl3‐induced borylative cyclization of aryl‐alkynes possessing ortho‐EMe (E=S, O) groups represents a simple, metal‐free method for the formation of C3‐borylated benzothiophenes and benzofurans. The dichloro(heteroaryl)borane primary products can be protected to form synthetically ubiquitous pinacol boronate esters or used in situ in Suzuki–Miyaura cross couplings to generate 2,3‐disubstituted heteroarenes from simple alkyne precursors in one pot. In a number of cases alkyne trans‐haloboration occurs alongside, or instead of, borylative cyclization and the factors controlling the reaction outcome are determined.
Rheological investigation of a random copolymer of polyacrylamide and polyacryloyl hydrazide (PAM‐ran‐PAH) for oil recovery applications
Authors: Raman Ujjwal Rewati , Sharma Tushar , Sangwai Jitendra S. , Ojha Umaprasana 
Published: November 2016

ABSTRACTIn this article, we synthesize and investigate the rheological properties of a random copolymer PAM‐ran‐PAH of polyacrylamide (PAM) and polyacryloyl hydrazide (PAH) and compare with the results of PAM at different temperature (30 and 80 °C) and salinity (0 and 1.0 wt %). At 30 °C, both PAM and PAM‐ran‐PAH exhibited non‐Newtonian rheology with both shear thinning and shear thickening responses. The rheological properties such as viscosity and moduli (G′ and G″) of PAM significantly deformed at elevated temperature (80 °C) and salinity (1.0 wt %), resulting no recovery in viscosity and moduli. On the other hand, the effect of temperature and salinity was found to be least on PAM‐ran‐PAH and showed better stability with the possibility of recovering its original rheological properties. The performance of PAM and PAM‐ran‐PAH was also characterized by enhanced oil recovery tests. The use of PAM‐ran‐PAH for polymer flooding, due to its stable rheology, resulted in an increase in the oil recovery than PAM. In general, the rheological behavior of PAM‐ran‐PAH as a chemical agent proved to be thermally stable than PAM, which clearly supports its use for saline environment and high temperature applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44648.
The feasibility of printing polylactic acid–nanohydroxyapatite composites using a low‐cost fused deposition modeling 3D printer
Authors: Esposito Corcione Carola , Gervaso Francesca , Scalera Francesca , Montagna Francesco , Sannino Alessandro , Maffezzoli Alfonso 
Published: November 2016

ABSTRACTThe current “gold standard” to treat bone lesions is allografts and autografts, both presenting important disadvantages such as risk of infection and morbidity. Synthetic grafts and scaffolds for bone regeneration represent a promising solution. Fused deposition modeling is a valid tool for developing synthetic bone grafts of complex shapes, which is a key issue. The possibility of building polylactic acid–nanohydroxyapatite (PLA/nanoHA) composites by 3D printing was systematically evaluated. PLA/nanoHA filaments for low‐cost 3D printers were produced by a multistep solvent‐free procedure and characterized by scanning electron microscopy, energy dispersive X‐ray spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry, and rheometry. TGA analysis confirmed the presence of the nanoHA amounts used in the composites, equal to 5 and 15 wt %. The glass‐transition temperature and degree of crystallinity of PLA are not influenced by presence of nanoHA, which remains substantially amorphous. The morphological analysis and compression testing on printed samples showed that nanoHA was uniformly dispersed within the PLA matrix and improved the PLA mechanical properties without changing the rheological performance. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44656.
Double‐Side Co‐Catalytic Activation of Anodic TiO2 Nanotube Membranes with Sputter‐Coated Pt for Photocatalytic H2 Generation from Water/Methanol Mixtures
Authors: Cha Gihoon , Altomare Marco , Truong Nguyen Nhat , Taccardi Nicola , Lee Kiyoung , Schmuki Patrik 
Published: November 2016

AbstractSelf‐standing TiO2 nanotube layers in the form of membranes are fabricated by self‐organizing anodization of Ti metal and a potential shock technique. The membranes are then decorated by sputtering different Pt amounts i) only at the top, ii) only at the bottom or iii) at both top and bottom of the tube layers. The Pt‐decorated membranes are transferred either in tube top‐up or in tube top‐down configuration onto FTO slides and are investigated, after crystallization, as photocatalysts for H2 generation using either front or back‐side light irradiation. Double‐side Pt‐decoration of the tube membranes leads to higher H2 generation rates (independently of tube and light‐irradiation configuration) compared to membranes decorated at only one side with similar overall Pt amounts. The results suggest that this effect cannot be only ascribed to the overall amount of Pt co‐catalyst as such but also to its distribution at both tube extremities. This leads to optimized light absorption and electron diffusion/transfer dynamics: the central part of the membranes acts as light‐harvesting zone and electrons therein generated can diffuse towards the Pt/TiO2 active zones (tube extremities) where they can react with the environment and generate H2.
Stimuli‐Responsive Cucurbit[7]uril‐Mediated BSA Nanoassembly for Uptake and Release of Doxorubicin
Authors: Barooah Nilotpal , Kunwar Amit , Khurana Raman , Bhasikuttan Achikanath C. , Mohanty Jyotirmayee 
Published: November 2016

AbstractWe report the construction of a non‐toxic nanoassembly of bovine serum albumin (BSA) protein and the cucurbit[7]uril macrocycle as well as its stimuli‐responsive breakage with adamantylamine or pH, which restores the protein structure and recognition properties. The assembly showed efficient loading and controlled release of a standard drug, doxorubicin (DOX), and the same was validated in live cells. The cell viability studies documented that the DOX‐loaded assembly mask the cytotoxicity of DOX and the toxicity can be revived at the target on demand, triggering its therapeutic activation. This is found to be more effective in the cancer cells. In addition, such host‐assisted protein assemblies are also highly promising for stabilizing/protecting the native protein structure, a viable approach to prevent/inhibit protein misfolding and aggregation.
Photoswitchable and Water‐Soluble Fluorescent Nano‐Aggregates Based on a Diarylethene–Dansyl Dyad and Liposome
Authors: Cheng Hongbo , Ma Pin , Wang Yanan , Hu Guofei , Fang Shibi , Fang Yanyan , Lin Yuan 
Published: November 2016

AbstractIn this work, a unique approach is developed to generate photoswitchable and water‐soluble fluorescent nano‐aggregates. Initially, a new light‐controlled diarylethene–dansyl dyad DAE 1 is formed by linking two dansyl fluorophores covalently to a symmetrical dithienylethene backbone, whose photophysical properties can be reversibly switched by optical stimuli. Subsequently, the water insolubility of the molecular switch 1 is overcome by incorporating it into the bilayer of liposome DPPC (1,2‐dihexadecanoyl‐sn‐glycero‐3‐phosphocholine) in water. This strategy creates stable fluorescent nano‐aggregates OF‐1@DPPC (≈25 nm diameter) that are soluble in an aqueous medium. The nano‐aggregates OF‐1@DPPC retain and even improve the photoswitchable fluorescence properties of DAE 1. More importantly, OF‐1@DPPC exhibits a remarkable photostability and fatigue resistance after 5 cycles of irradiation with UV and visible light, which is crucial for its practical application.
Self‐calibration strategy for a LOFAR solar radio burst observation
Authors: Vocks C. , Mann G. , Breitling F. 
Published: November 2016

AbstractThe LOw Frequency ARray (LOFAR) is a novel radio interferometer consisting of a central core near Exloo in the Netherlands, remote stations in the Netherlands, and international stations. It observes in two frequency bands, the low band of 10–90 MHz and the high band of 110–250 MHz. The key science project “Solar Physics and Space Weather with LOFAR” aims at studying the solar activity and its influence on interplanetary space. Solar radio radiation in the low and high band emanates from the upper and middle corona, respectively. We present early commissioning observations of the Sun, that serendipitously include a weak radio burst. Since no external calibrator was observed, a self‐calibration approach has tobe used. This works well for the quiet Sun, but not for the burst data. We develop a self‐calibration strategy for radio bursts, and discuss the general properties of such a self‐calibration method. Our results lead to the conclusion that external calibrators with known source structure should generally be preferred. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Curcumin as a multifaceted compound against human papilloma virus infection and cervical cancers: A review of chemistry, cellular, molecular, and preclinical features
Authors: Teymouri Manouchehr , Pirro Matteo , Johnston Thomas P. , Sahebkar Amirhosein 
Published: November 2016

AbstractCurcumin, the bioactive polyphenolic ingredient of turmeric, has been extensively studied for its effects on human papilloma virus (HPV) infection as well as primary and malignant squamous cervical cancers. HPV infections, especially those related to HPV 16 and 18 types, have been established as the leading cause of cervical cancer; however, there are also additional contributory factors involved in the etiopathogenesis of cervical cancers. Curcumin has emerged as having promising chemopreventive and anticancer effects against both HPV‐related and nonrelated cervical cancers. In this review, we first discuss the biological relevance of curcumin and both its pharmacological effects and pharmaceutical considerations from a chemical point of view. Next, the signaling pathways that are modulated by curcumin and are relevant to the elimination of HPV infection and treatment of cervical cancer are discussed. We also present counter arguments regarding the effects of curcumin on signaling pathways and molecular markers dysregulated by benzo(a)pyrene (Bap), a carcinogen found in pathological cervical lesions of women who smoke frequently, and estradiol, as two important risk factors involved in persistent HPV‐infection and cervical cancer. Finally, various strategies to enhance the pharmacological activity and pharmacokinetic characteristics of curcumin are discussed with examples of studies in experimental models of cervical cancer. © 2016 BioFactors, 43(3):331–346, 2017
Reconstruction of biological pathways and metabolic networks from in silico labeled metabolites
Authors: Hadadi Noushin , Hafner Jasmin , Soh Keng Cher , Hatzimanikatis Vassily 
Published: November 2016

AbstractReaction atom mappings track the positional changes of all of the atoms between the substrates and the products as they undergo the biochemical transformation. However, information on atom transitions in the context of metabolic pathways is not widely available in the literature. The understanding of metabolic pathways at the atomic level is of great importance as it can deconvolute the overlapping catabolic/anabolic pathways resulting in the observed metabolic phenotype. The automated identification of atom transitions within a metabolic network is a very challenging task since the degree of complexity of metabolic networks dramatically increases when we transit from metabolite‐level studies to atom‐level studies. Despite being studied extensively in various approaches, the field of atom mapping of metabolic networks is lacking an automated approach, which (i) accounts for the information of reaction mechanism for atom mapping and (ii) is extendable from individual atom‐mapped reactions to atom‐mapped reaction networks. Hereby, we introduce a computational framework, iAM.NICE (in silico Atom Mapped Network Integrated Computational Explorer), for the systematic atom‐level reconstruction of metabolic networks from in silico labelled substrates. iAM.NICE is to our knowledge the first automated atom‐mapping algorithm that is based on the underlying enzymatic biotransformation mechanisms, and its application goes beyond individual reactions and it can be used for the reconstruction of atom‐mapped metabolic networks. We illustrate the applicability of our method through the reconstruction of atom‐mapped reactions of the KEGG database and we provide an example of an atom‐level representation of the core metabolic network of E. coli.
Modern Approaches to Discovering New Hydroxynitrile Lyases for Biocatalysis
Authors: Padhi Santosh Kumar 
Published: November 2016

AbstractHydroxynitrile lyases (HNLs) have grown in importance from laboratory to industry due to their potential to catalyze stereoselective C−C bond‐formation reactions in the synthesis of several chiral intermediates, such as enantiopure α‐cyanohydrins, β‐nitro alcohols, and their derivatives with multiple functional groups. With these wide applications, the demand for finding new HNLs has increased, and this has led to exploration not only of new HNLs but also of new ways to discover them. An exclusive review article on HNLs by Asano et al. in 2011 described the discovery of HNLs along with their applications. Since then many scientific advancements have been seen in this area. This article aims to highlight the modern HNL discovery approaches, based mainly on 1) genome mining, 2) use of INTMSAlign software, 3) rational design (based on a millipede HNL), 4) evolution of catalytic mechanisms, 5) protein engineering guided by catalytic mechanisms, and 6) screening of plants with cyanogen glycoside (CG) content. This description is followed by future prospects. Overall this review represents the present state and the future potential of HNL discovery approaches, and so might be hoped to be instrumental not only in exploration of new HNLs but also in the invention of methods for potential biotechnological applications.
Bifunctionality of ActIV as a Cyclase‐Thioesterase Revealed by in Vitro Reconstitution of Actinorhodin Biosynthesis in Streptomyces coelicolor A3(2)
Authors: Taguchi Takaaki , Awakawa Takayoshi , Nishihara Yukitaka , Kawamura Michiho , Ohnishi Yasuo , Ichinose Koji 
Published: November 2016

AbstractType II polyketide synthases iteratively generate a nascent polyketide thioester of the acyl carrier protein (ACP); this is structurally modified to produce an ACP‐free intermediate towards the final metabolite. However, the timing of ACP off‐loading is not well defined because of the lack of an apparent thioesterase (TE) among relevant biosynthetic enzymes. Here, ActIV, which had been assigned as a second ring cyclase (CYC) in actinorhodin (ACT) biosynthesis, was shown to possess TE activity in vitro with a model substrate, anthraquinone‐2‐carboxylic acid‐N‐acetylcysteamine. In order to investigate its function further, the ACT biosynthetic pathway in Streptomyces coelicolor A3(2) was reconstituted in vitro in a stepwise fashion up to (S)‐DNPA, and the product of ActIV reaction was characterized as an ACP‐free bicyclic intermediate. These findings indicate that ActIV is a bifunctional CYC‐TE and provide clear evidence for the release timing of the intermediate from the ACP anchor.