bluuebunny/crossref_metadata_2025_split huggingface dataset:
Informed Molecular Design of Conjugated Oligoelectrolytes To Increase Cell Affinity and Antimicrobial Activity
Authors: Zhou Cheng , Chia Geraldine W. N. , Ho James C. S. , Seviour Thomas , Sailov Talgat , Liedberg Bo , Kjelleberg Staffan , Hinks Jamie , Bazan Guillermo C. 
Published: April 2018

AbstractMembrane‐intercalating conjugated oligoelectrolytes (COEs) are emerging as potential alternatives to conventional, yet increasingly ineffective, antibiotics. Three readily accessible COEs, belonging to an unreported series containing a stilbene core, namely D4, D6, and D8, were designed and synthesized so that the hydrophobicity increases with increasing side‐chain length. Decreased aqueous solubility correlates with increased uptake by E. coli. The minimum inhibitory concentration (MIC) of D8 is 4 μg mL−1 against both E. coli and E. faecalis, with an effective uptake of 72 %. In contrast, the MIC value of the shortest COE, D4, is 128 μg mL−1 owing to the low cellular uptake of 3 %. These findings demonstrate the application of rational design to generate efficacious antimicrobial COEs that have potential as low‐cost antimicrobial agents.
Copper(I)‐Catalyzed Enantio‐ and Diastereodivergent Borylative Coupling of Styrenes and Imines
Authors: Itoh Taisuke , Kanzaki Yamato , Shimizu Yohei , Kanai Motomu 
Published: April 2018

AbstractWe report copper(I)‐catalyzed enantio‐ and diastereodivergent borylative coupling of styrenes and imines to produce enantiomerically‐enriched α,β‐dibranched γ‐boryl amine derivatives. Each of the four possible stereoisomers of the products, derived from the two contiguous stereocenters, was selectively accessible by choosing a proper chiral ligand for the copper catalyst. This method, which combines catalyst‐controlled stereodivergency and constitutional divergency derived from the lynchpin motif (i.e., the C−B bond), offers a strategy for addressing the construction of molecular structural diversity concomitant with precise chirality control.
Studies on thermal behavior of imidazole diamine based benzoxazines
Authors: Kannan Kesavan , Krishnan Srinivasan , Chavali Murthy , Alagar Muthukaruppan 
Published: April 2018

ABSTRACTThe objective of the present work is to develop a novel type of structurally modified benzoxazines with improved performance characteristics using imidazole core based diamine with formaldehyde and different types of phenolic compounds in order to utilize them for high‐performance applications. In this work, an attempt has been made to bring down the polymerization temperature of the benzoxazine monomers, which is one of the most deficient factor restrict the applications of benzoxazines, when used in the form of adhesives, sealants, encapsulants, and matrices with other substrates, though they possess numerous advantages and valuable properties than those of other available thermosets. In this context, in this study, two approaches have been adopted to bring down the polymerization temperature, viz., (i) the development of structurally modified benzoxazine monomers with imidazole core and (ii) an incorporation of varying nature of chemical compounds as catalysts, to lower the polymerization temperature and to enhance the thermal stability and char yield. Three types of benzoxazines were developed using imidazole core based diamine with monohydric phenols and formaldehyde, at appropriate conditions. The molecular structure of benzoxazines was confirmed from Fourier transform infrared spectroscopy and 1H‐nuclear magnetic resonance analysis. From data, it was observed that the imidazole diamine based benzoxazines prepared from 1‐naphthol exhibits lower curing temperature of about 192 °C than that of other samples studied in this work. In addition, the influencing effect of catalysts viz., 4‐hydroxy acetophenone, 4‐hydroxy benzaldehyde, 4‐hydroxyphenyl maleimide, and thiodipropionic acid (TPA) on thermal properties of benzoxazines also was studied. Among the catalysts, it was found that the TPA is the most efficient catalyst. In the case of imidazole diamine based benzoxazines prepared from cyanophenol, the TPA reduces value of polymerization temperature (Tp) from 217 to 167 °C. The thermogravimetric analysis indicates that thermal stability of the benzoxazines are improved to a significant extent when 10 wt % catalysts were incorporated into the system. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46562.
Investigation of the clay sensitivity and cement hydration process of modified HPEG‐type polycarboxylate superplasticizers
Authors: Zhao Hongwei , Liao Bing , Nian Fuwei , Wang Kun , Guo Ying , Pang Hao 
Published: April 2018

ABSTRACTIn this work, three kinds of HPEG‐type polycarboxylate superplasticizers (PCs) were synthesized with three kinds of typical functional monomers: [diallyl dimethyl ammonium chloride (DMDAAC), 2‐hydroxyethyl methacrylate (HEMA), and 2‐(dimethylamino) ethyl methacrylate (DMAM), respectively. The effects of montmorillonite clay on the fluidity of cement/PC pastes were investigated. It was found that the fluidity was negatively affected by the clays in the order: DMAM‐PC < HEMA‐PC < conventional PC (CPC) < DMDAAC‐PC. The DMAM‐PC was found to disperse cement well even in presence of montmorillonite clay. The dispersion performance of DMDAAC‐PC was much more effectively affected by clay due to the reaction between ammonium and montmorillonite. More study including mortar fluidity, adsorption behavior and morphology of the cement samples were investigated in details. Thermogravimetric analysis and X‐ray diffraction experiments allowed us to observe the influence of PCs on the hydrated products. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46572.
A novel combination of sandwich and co‐continuous structure based on polypropylene and styrene‐butadiene‐styrene block copolymer formed with wide range of polypropylene content
Authors: Wang Ping , Zhang Jun 
Published: April 2018

ABSTRACTThe styrene–butadiene–styrene block copolymer (SBS)/polypropylene (PP) blends with a unique sandwich layered co‐continuous structure were prepared by melt compounding. Differing from single conventional co‐continuous and sandwich structure, this structure was formed, where pure PP and co‐continuous SBS/PP phase acting as the face sheets and core. Even though the volume content was 20 or 10 vol %, PP always amazingly formed a continuous phase in SBS/PP blends, whereas the morphology of SBS phase relatively changed from dispersed particles to continuous network as its content increased to 50 vol %. For immiscible SBS/PP blends, due to the huge difference of complex viscosity and surface tension between SBS and PP, a pure PP layer existed on the surface of blends which can be ascribed to the PP enrichment. Herein, the structure of blends with more than 50 vol % SBS was presented as sandwich layered co‐continuous structure by combining the pure PP layer and co‐continuous structure. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2018,135, 46580.
Influence of thermal and morphological characteristics on mechanical responses of polypropylene/γ‐irradiated elastomer blends
Authors: Dutta Anindya , Ghosh Anup K. 
Published: April 2018

ABSTRACTThe approach of this paper is to examine the mechanical responses of polypropylene (PP)/γ‐irradiated ethylene acrylic elastomer blends and subsequently compare them with the PP/unirradiated ethylene acrylic elastomer blends. Thorough correlations were drawn between the mechanical characteristics of blends and their morphological, thermal, thermomechanical, and fractured surface morphological aspects. The idea of carrying out γ‐irradiation was to introduce crosslinking points in the elastomer phase. For better understanding, correlations between the impact test results and the fractured surface morphologies were analyzed. The limited tensile properties of PP/γ‐irradiated elastomer blends were attributed not only to the poor interfacial adhesion, obtained by fitting with several theoretical mechanical models, but also to the substantially higher elastomer particle size in the blends than in the PP/unirradiated elastomer blends. The higher loss modulus and tan δ values for PP/unirradiated elastomer blends along with the attainment of much smaller particles of elastomers were responsible for the phenomenal increase in impact properties, which was actually attributed to the formation of crazes inside the dispersed phase during applied impact stress. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2018,135, 46597.
Mechanism of internal and external electron donor effects on propylene polymerization with MgCl2‐supported Ziegler–Natta catalyst: New evidences based on active center counting
Authors: Weng Yuhong , Jiang Baiyu , Fu Zhisheng , Fan Zhiqiang 
Published: April 2018

ABSTRACTTwo TiCl4/Di/MgCl2 type supported Ziegler–Natta catalysts were prepared by loading dibutylphthalate or dicyclopentyldimethoxysilane (DCPDMS) (internal donor, Di) and TiCl4 on activated δ‐MgCl2 in sequence, and a blank catalyst was prepared by loading TiCl4 on the same δ‐MgCl2 without adding Di. These catalysts have similar specific surface area and pore size distribution, thus form a suitable base for comparative studies. Propylene polymerization with the catalysts was conducted in n‐heptane slurry using triethylaluminum (TEA) as cocatalyst, and the effects of Di as well as De (external donor, in this work it was DCPDMS) on the number of active centers, the distribution of active centers among three polypropylene (PP) fractions (isotactic, medium isotactic, and atactic PP chains), and chain propagation rate constants of the PP fractions were studied by counting the number of active centers in the PP fractions using a method based on selective quench‐labeling of the propagation chains by 2‐thiophenecarbonyl chloride. When De was not added in the polymerization, introducing a phthalate type Di in the catalyst evidently changed the active center distribution by enhancing the proportion of active centers producing isotactic PP (iPP) (
), but scarcely changed reactivities of the three groups of active centers forming the three fractions. When the De was added in the polymerization system with TiCl4/phthalate/MgCl2 catalyst, further shifting of active center distribution in favor of
took place, meanwhile reactivities of the three groups of active centers also remarkably changed in favor of
. Mutual effects of these changes led to overwhelming dominance of iPP production in the TiCl4/Di/MgCl2–TEA/De system (Di = phthalate, De = alkoxysilane). In contrast, though using alkoxysilane as Di also caused shifting of active center distribution in favor of
when De was not added, addition of alkoxysilane De caused reverse shifting of active center distribution in favor of those producing PP of lower stereoregularity. This unfavorable change largely counteracted the reactivity changes in favor of
caused by the De, rendering the catalytic system rather poor isospecificity. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46605.
Papillary Architecture and Functional Characterization of Mucosubstances in the Sheep Tongue
Authors: Erdoğan Serkan , Sağsöz Hakan 
Published: April 2018

ABSTRACTThis research aimed to reveal the general morphology and topographic distribution of lingual papillae, epithelial characteristics, mucosal structure, and glands with their mucin content in the sheep tongue, with consideration of species‐specific characteristics. The tongues of ten sheep were analyzed for this purpose. Filiform and fungiform papillae existed within the borders of the ventral surface of the lingual apex. The majority of the filiform papillae had multiple secondary projections. Fungiform papillae were also seen on the lingual torus among lenticular papillae, as well as 6 to 10 circumvallate papillae arranged on its caudal border. The species‐specific details of the general anatomical structure of the tongue were determined and, in general, the papillary organization in the sheep was similar to goats, while the papillary organization also was similar to features with deer species, specifically the filiform papilla from the mechanical papillae and fungiform papilla from the gustatory papillae. Neutral and weak sulfated mucins and N‐acetyl sialomucins were located in seromucous glands, salivary duct epithelium and von Ebner's glands. Carboxylated acid mucins and N‐acetyl sialomucins were not present in seromucous and von Ebner's glands. In seromucous glands, MUC1, MUC5AC, and MUC6 localized only in epithelial cells of ducts, whereas MUC2 localized in both glandular and ductal epithelial cells. All MUCs were present in both von Ebner's glands and salivary ducts. We showed that this mucin composition, may serve as a physical barrier in the initial section of the digestive system. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc.
The Nasal Cavity of the Rat and Mouse—Source of Mesenchymal Stem Cells for Treatment of Peripheral Nerve Injury
Authors: Alvites Rui Damásio , Caseiro Ana Rita , Pedrosa Sílvia Santos , Branquinho Mariana Esteves , Varejão Artur S.P. , Maurício Ana Colette 
Published: April 2018

ABSTRACTThe nasal cavity performs several crucial functions in mammals, including rodents, being involved in respiration, behavior, reproduction, and olfaction. Its anatomical structure is complex and divided into several regions, including the olfactory recess where the olfactory mucosa (OM) is located and where the capture and interaction with the environmental odorants occurs. Among the cells of this region are the OM mesenchymal stem cells (MSCs), whose location raises the possibility that these cells could be involved in the peculiar ability of the olfactory nerve to regenerate continuously throughout life, although this relationship has not yet been confirmed. These cells, like all MSCs, present functional characteristics that make them candidates in new therapies associated with regenerative medicine, namely to promote the regeneration of the peripheral nerve after injury. The availability of stem cells to be therapeutically applied essentially depends on their collection in the tissue of origin. In the case of mice and rat's OM‐MSCs, knowledge about the anatomy and histology of their nasal cavity is essential in establishing effective collection protocols. The present article describes the morphological characteristics of rodent's OM and establishes an alternative protocol for access to the olfactory recess and collection of the OM. Anat Rec, 301:1678–1689, 2018. © 2018 Wiley Periodicals, Inc.
Probing chemical space of tick‐borne encephalitis virus reproduction inhibitors with organoselenium compounds
Authors: Orlov Alexey A. , Eletskaya Anastasia A. , Frolov Konstantin A. , Golinets Anastasia D. , Palyulin Vladimir A. , Krivokolysko Sergey G. , Kozlovskaya Liubov I. , Dotsenko Victor V. , Osolodkin Dmitry I. 
Published: April 2018

AbstractTick‐borne encephalitis virus (TBEV), a member of the genus Flavivirus, is the leading cause of arboviral neuroinfections in Europe. Only a few classes of the nucleoside and non‐nucleoside inhibitors were investigated against TBEV reproduction. Paving the way to previously unexplored areas of anti‐TBEV chemical space, we assessed the inhibition of TBEV reproduction in the plaque reduction assay by various compounds derived from cyanothioacetamide and cyanoselenoacetamide. Compounds from seven classes, including 4‐(alkylthio)‐2‐aryl‐3‐azaspiro[5.5]undec‐4‐ene‐1,1,5‐tricarbonitriles, 3‐arylamino‐2‐(selenazol‐2‐yl)acrylonitriles, ethyl 6‐(alkylseleno)‐5‐cyano‐2‐oxo‐1,2‐dihydropyridine‐3‐carboxylates, 6‐(alkylseleno)‐2‐oxo‐1,4,5,6‐tetrahydropyridine‐3‐carbonitriles, 2‐(alkylseleno)‐5‐oxo‐1,4,5,6,7,8‐hexahydroquinoline‐3‐carbonitriles, 8‐selenoxo‐3,5,7,11‐tetraazatricyclo[7.3.1.02,7]tridec‐2‐ene‐1,9‐dicarbonitriles, and selenolo[2,3‐b]quinolines, inhibited TBEV reproduction with EC50 values in the micromolar range while showing moderate cytotoxicity and no inhibition of enterovirus reproduction. Thus, new scaffolds with promising anti‐TBEV activity were found.
Enantioselective Mukaiyama–Michael Reaction Catalyzed by a Chiral Rhodium Complex Based on Pinene‐Modified Pyridine Ligands
Authors: Gong Jun , Wan Qian , Kang Qiang 
Published: April 2018

AbstractThe rhodium complex Λ‐Rh1 containing chiral pinene‐modified pyridine ligands is prepared through a two‐step synthetic procedure; it exhibits excellent reactivity and enantiocontrol towards the enantioselective Mukaiyama–Michael reaction of α,β‐unsaturated 2‐acyl imidazoles with silyl enol ethers, affording enantioenriched 1,5‐dicarbonyl compounds in good yields (up to 99 %) with excellent enantioselectivities (up to 99 % ee).
C−H Alkenylation of Pyrroles by Electronically Matching Ligand Control
Authors: Kim Hyun Tae , Lee Woohyeong , Kim Eunmin , Joo Jung Min 
Published: April 2018

AbstractDirecting group and substrate control strategies have frequently been employed for the regioselective C−H alkenylation of acid‐ and oxidant‐sensitive pyrrole heterocycles. We developed an undirected, aerobic strategy for the C−H alkenylation of N‐alkylpyrroles by ligand control. For C2‐alkenylation of electron‐rich N‐alkylpyrroles, an electrophilic palladium catalyst derived from Pd(OAc)2 and 4,5‐diazafluoren‐9‐one (DAF) was used. Alternatively, a combination of Pd(OAc)2 and a mono‐protected amino acid ligand, Ac‐Val‐OH, was useful for C5‐alkenylation of N‐alkylpyrroles possessing electron‐withdrawing groups at the C2 position. This approach based on the electronic effects of heterocycles and catalysts can rapidly provide a wide range of alkenyl pyrroles from readily available N‐alkylpyrroles and alkenes.
Selectivity Control on Hydrogenation of Substituted Nitroarenes through End‐On Adsorption of Reactants in Zeolite‐Encapsulated Platinum Nanoparticles
Authors: Chen Qiang , Wang Mengyue , Zhang Chengxi , Ren Kui , Xin Yue , Zhao Ming , Xing Enhui 
Published: April 2018

AbstractPlatinum nanoparticles encapsulated into zeolite Y (Pt@Y catalyst) exhibit excellent catalytic selectivity in the hydrogenation of substituted nitroarenes to form the corresponding aromatic amines, even after complete conversion. With the hydrogenation of p‐chloronitrobenzene as a model, the role of zeolite encapsulation toward perfect selectivity can be attributed to constraint of the substrate adsorbed on the platinum surface in an end‐on conformation. This conformation results in the activation of only one adsorbed group, with little influence on the other one in the molecule. Owing to a much lower apparent activation energy of Pt@Y for the hydrogenation of a separately adsorbed nitro group than that of the adsorbed chloro group, the Pt@Y catalyst can prevent hydrodechlorination of p‐chloronitrobenzene under mild conditions. Moreover, such a conformation results in a reduced adsorption energy of target p‐chloroaniline on the platinum surface; thus suppressing the reactivity of hydrodechlorination of p‐chloroaniline to circumvent further C−Cl bond breakage.
Some Controllability Aspects for Iterative Learning Control
Authors: Leissner Patrik , Gunnarsson Svante , Norrlöf Mikael 
Published: April 2018

AbstractSome controllability aspects for iterative learning control (ILC) are discussed. Via a batch (lifted) description of the problem a state space model of the system to be controlled is formulated in the iteration domain. This model provides insight and enables analysis of the conditions for and relationships between controllability, output controllability and target path controllability. In addition, the property miminum lead target path controllability is introduced. This property, which is connected to the number of time delays, plays an important role in the design of ILC algorithms. The properties are illustrated by a numerical example.
A Filter‐based Clock Synchronization Protocol for Wireless Sensor Networks
Authors: Yang Wenlun , Fu Minyue 
Published: April 2018

AbstractClock parameters in wireless sensors experience slow changes due to low‐cost construction and environmental conditions. In this paper, a filter‐based distributed protocol, called FBP, is proposed to dynamically achieve clock synchronization for wireless sensor networks. The idea of FBP is derived from a first‐order filter which is robust to environmental noises. The proposed protocol is fully distributed, meaning that each node relies only on its local clock readings and reading announcements from its neighbouring sensor nodes. This will allow the proposed protocol applicable to large sensor networks. By applying FBP, the compensated clock skews can be bounded into a small steady‐state error. Numerical simulations show that the proposed protocol yields better performances in both convergence property and synchronization accuracy.
Quadrotor Control Via Robust Generalized Dynamic Inversion and Adaptive Non‐Singular Terminal Sliding Mode
Authors: Ansari Uzair , Bajodah Abdulrahman H. , Hamayun Mirza Tariq 
Published: April 2018

AbstractA robust two‐loops structured control system design for quadrotor's position/attitude trajectory tracking is proposed. The aim of the outer loop is to provide the roll/pitch tilting commands to the inner loop, which in turns generates the tilting angles that control the quadrotor's center of gravity in the horizontal plane. The outer loop utilizes Robust Generalized Dynamic Inversion (RGDI) of a prescribed asymptotically stable differential equation in the deviation function of the horizontal position coordinates from their reference trajectories. The inner loop employs an Adaptive Non‐singular Terminal Sliding Mode (ANTSM) to control the tilting angles, in addition to controlling the yaw attitude angle and the vertical position coordinate. The proposed scheme solves the singularity avoidance problems of generalized inversion and terminal sliding mode control. The stability of outer and inner loop is ensured by utilizing positive definite Lyapunov energy function for stable tracking performance against parametric variations and bounded unknown external disturbances. Numerous simulations are conducted on a six Degrees of Freedom (DoF) quadrotor model in the presence of parametric variations, un modeled dynamics, and external disturbances.
miRNA‐regulated transcription associated with mouse strains predisposed to hypnotic effects of ethanol
Authors: Vestal B. , Russell P. , Radcliffe R.A. , Bemis L. , Saba L.M. , Kechris K. 
Published: April 2018

AbstractIntroductionStudying innate sensitivity to ethanol can be an important first step toward understanding alcohol use disorders. In brain, we investigated transcripts, with evidence of miRNA modulation related to a predisposition to the hypnotic effect of ethanol, as measured by loss of righting reflex (LORR).MethodsExpression of miRNAs (12 samples) and expression of mRNAs (353 samples) in brain were independently analyzed for an association with LORR in mice from the LXS recombinant inbred panel gathered across several small studies. These results were then integrated via a meta‐analysis of miRNA–mRNA target pairs identified in miRNA‐target interaction databases.ResultsWe found 112 significant miRNA–mRNA pairs where a large majority of miRNAs and mRNAs were highly interconnected. Most pairs indicated a pattern of increased levels of miRNAs and reduced levels of mRNAs being associated with more alcohol‐sensitive strains. For example, CaMKIIn1 was targeted by multiple miRNAs associated with LORR. CAMK2N1 is an inhibitor of CAMK2, which among other functions, phosphorylates, or binds to GABAA and NMDA receptors.ConclusionsOur results suggest a novel role of miRNA‐mediated regulation of an inhibitor of CAMK2 and its downstream targets including the GABAA and NMDA receptors, which have been previously implicated to have a role in ethanol‐induced sedation and sensitivity.