bluuebunny/crossref_metadata_2025 huggingface dataset:
A squalene synthase-like enzyme initiates production of tetraterpenoid hydrocarbons in Botryococcus braunii Race L
Authors: Thapa Hem R. , Naik Mandar T. , Okada Shigeru , Takada Kentaro , Molnár István , Xu Yuquan , Devarenne Timothy P.
Published: April 2016

The green microalga Botryococcus braunii is considered a promising biofuel feedstock producer due to its prodigious accumulation of hydrocarbon oils that can be converted into fuels. B. braunii Race L produces the C40 tetraterpenoid hydrocarbon lycopadiene via an uncharacterized biosynthetic pathway. Structural similarities suggest this pathway follows a biosynthetic mechanism analogous to that of C30 squalene. Confirming this hypothesis, the current study identifies C20 geranylgeranyl diphosphate (GGPP) as a precursor for lycopaoctaene biosynthesis, the first committed intermediate in the production of lycopadiene. Two squalene synthase (SS)-like complementary DNAs are identified in race L with one encoding a true SS and the other encoding an enzyme with lycopaoctaene synthase (LOS) activity. Interestingly, LOS uses alternative C15 and C20 prenyl diphosphate substrates to produce combinatorial hybrid hydrocarbons, but almost exclusively uses GGPP in vivo. This discovery highlights how SS enzyme diversification results in the production of specialized tetraterpenoid oils in race L of B. braunii.
3D-QSAR and docking studies of flavonoids as potent Escherichia coli inhibitors
Authors: Fang Yajing , Lu Yulin , Zang Xixi , Wu Ting , Qi XiaoJuan , Pan Siyi , Xu Xiaoyun
Published: April 2016

Flavonoids are potential antibacterial agents. However, key substituents and mechanism for their antibacterial activity have not been fully investigated. The quantitative structure-activity relationship (QSAR) and molecular docking of flavonoids relating to potent anti-Escherichia coli agents were investigated. Comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) were developed by using the pIC50 values of flavonoids. The cross-validated coefficient (q2) values for CoMFA (0.743) and for CoMSIA (0.708) were achieved, illustrating high predictive capabilities. Selected descriptors for the CoMFA model were ClogP (logarithm of the octanol/water partition coefficient), steric and electrostatic fields, while, ClogP, electrostatic and hydrogen bond donor fields were used for the CoMSIA model. Molecular docking results confirmed that half of the tested flavonoids inhibited DNA gyrase B (GyrB) by interacting with adenosine-triphosphate (ATP) pocket in a same orientation. Polymethoxyl flavones, flavonoid glycosides, isoflavonoids changed their orientation, resulting in a decrease of inhibitory activity. Moreover, docking results showed that 3-hydroxyl, 5-hydroxyl, 7-hydroxyl and 4-carbonyl groups were found to be crucial active substituents of flavonoids by interacting with key residues of GyrB, which were in agreement with the QSAR study results. These results provide valuable information for structure requirements of flavonoids as antibacterial agents.
Production and characterization of tearless and non-pungent onion
Authors: Kato Masahiro , Masamura Noriya , Shono Jinji , Okamoto Daisaku , Abe Tomoko , Imai Shinsuke
Published: April 2016

The onion lachrymatory factor (LF) is produced from trans-S-1-propenyl-L-cysteine sulfoxide (PRENCSO) through successive reactions catalyzed by alliinase (EC 4.4.1.4) and lachrymatory factor synthase (LFS), and is responsible for the tear inducing-property and the pungency of fresh onions. We developed tearless, non-pungent onions non-transgenically by irradiating seeds with neon-ion at 20 Gy. The bulbs obtained from the irradiated seeds and their offspring bulbs produced by selfing were screened by organoleptic assessment of tear-inducing property or HPLC analysis of LF production. After repeated screening and seed production by selfing, two tearless, non-pungent bulbs were identified in the third generation (M3) bulbs. Twenty M4 bulbs obtained from each of them showed no tear-inducing property or pungency when evaluated by 20 sensory panelists. The LF production levels in these bulbs were approximately 7.5-fold lower than those of the normal onion. The low LF production levels were due to reduction in alliinase activity, which was a result of low alliinase mRNA expression (less than 1% of that in the normal onion) and consequent low amounts of the alliinase protein. These tearless, non-pungent onions should be welcomed by all who tear while chopping onions and those who work in facilities where fresh onions are processed.
Imaging of Angiotropism/Vascular Co-Option in a Murine Model of Brain Melanoma: Implications for Melanoma Progression along Extravascular Pathways
Authors: Bentolila Laurent A. , Prakash Roshini , Mihic-Probst Daniela , Wadehra Madhuri , Kleinman Hynda K. , Carmichael Thomas S. , Péault Bruno , Barnhill Raymond L. , Lugassy Claire
Published: April 2016

Angiotropism/pericytic mimicry and vascular co-option involve tumor cell interactions with the abluminal vascular surface. These two phenomena may be closely related. However, investigations of the two processes have developed in an independent fashion and different explanations offered as to their biological nature. Angiotropism describes the propensity of tumor cells to spread distantly via continuous migration along abluminal vascular surfaces, or extravascular migratory metastasis (EVMM). Vascular co-option has been proposed as an alternative mechanism by which tumors cells may gain access to a blood supply. We have used a murine brain melanoma model to analyze the interactions of GFP human melanoma cells injected into the mouse brain with red fluorescent lectin-labeled microvascular channels. Results have shown a striking spread of melanoma cells along preexisting microvascular channels and features of both vascular co-option and angiotropism/pericytic mimicry. This study has also documented the perivascular expression of Serpin B2 by angiotropic melanoma cells in the murine brain and in human melanoma brain metastases. Our findings suggest that vascular co-option and angiotropism/pericytic mimicry are closely related if not identical processes. Further studies are needed in order to establish whether EVMM is an alternative form of cancer metastasis in addition to intravascular cancer dissemination.
Interactive effect of microstructure and cavity dimension on filling behavior in micro coining of pure nickel
Authors: Wang Chuanjie , Wang Chunju , Xu Jie , Zhang Peng , Shan Debin , Guo Bin
Published: April 2016

In this study, interactive effects of microstructure and cavity dimension on the filling behaviors in micro coining were investigated. The results indicate that the filling ability is dependent on both the cavity width t and the ratio of cavity width to grain size t/d strongly. The critical ratio t/d for the worst filling ability increases with cavity width t and tends to disappear when the cavity width t increases to 300 μm. A polycrystalline filling model considering the friction size effect, effect of constrained grains by the tools, grain size, cavity width and ratio of cavity width to grain size is proposed to reveal the filling size effect in micro coining. A quasi in-situ Electron Backscatter Diffraction (EBSD) method is proposed to investigate filling mechanism in micro coining. When several grains across the cavity width, each grain deforms heterogeneously to ordinate the deformation compatibility. When there is only one grain across the cavity width, the grain is fragmented into several smaller grains with certain prolongation along the extrusion direction to coordinate the deformation in the cavity. This is different from the understandings before. Then the filling deformation mechanism is revealed by a proposed model considering the plastic flow in micro coining.
Fano resonance of Li-doped KTa1−xNbxO3 single crystals studied by Raman scattering
Authors: Rahaman M. M. , Imai T. , Sakamoto T. , Tsukada S. , Kojima S.
Published: April 2016

The enhancement of functionality of perovskite ferroelectrics by local structure is one of current interests. By the Li-doping to KTa1−xNbxO3 (KTN), the large piezoelectric and electro-optic effects were reported. In order to give new insights into the mechanism of doping, the microscopic origin of the Fano resonance induced by the local structure was investigated in 5%Li-doped KTN single crystals by Raman scattering. The coupling between the continuum states and the transverse optical phonon near 196 cm−1 (Slater mode) caused a Fano resonance. In the vicinity of the cubic-tetragonal phase transition temperature, TC-T = 31 °C, the almost disappearance of the Fano resonance and the remarkable change of the central peak (CP) intensity were observed upon heating. The local symmetry of the polar nanoregions (PNRs), which was responsible for the symmetry breaking in the cubic phase, was determined to E(x, y) symmetry by the angular dependence of Raman scattering. The electric field induced the significant change in the intensity of both CP and Fano resonance. From these experimental results, it is concluded that the origin of the Fano resonance in Li-doped KTN crystals is the coupling between polarization fluctuations of PNRs and the Slater mode, both belong to the E(x, y) symmetry.
Competing effect of spin-orbit torque terms on perpendicular magnetization switching in structures with multiple inversion asymmetries
Authors: Yu Guoqiang , Akyol Mustafa , Upadhyaya Pramey , Li Xiang , He Congli , Fan Yabin , Montazeri Mohammad , Alzate Juan G. , Lang Murong , Wong Kin L. , Khalili Amiri Pedram , Wang Kang L.
Published: April 2016

Current-induced spin-orbit torques (SOTs) in structurally asymmetric multilayers have been used to efficiently manipulate magnetization. In a structure with vertical symmetry breaking, a damping-like SOT can deterministically switch a perpendicular magnet, provided an in-plane magnetic field is applied. Recently, it has been further demonstrated that the in-plane magnetic field can be eliminated by introducing a new type of perpendicular field-like SOT via incorporating a lateral structural asymmetry into the device. Typically, however, when a current is applied to such devices with combined vertical and lateral asymmetries, both the perpendicular field-like torque and the damping-like torque coexist, hence jointly affecting the magnetization switching behavior. Here, we study perpendicular magnetization switching driven by the combination of the perpendicular field-like and the damping-like SOTs, which exhibits deterministic switching mediated through domain wall propagation. It is demonstrated that the role of the damping-like SOT in the deterministic switching is highly dependent on the magnetization direction in the domain wall. By contrast, the perpendicular field-like SOT is solely determined by the relative orientation between the lateral structural asymmetry and the current direction, regardless of the magnetization direction in the domain wall. The experimental results further the understanding of SOTs-induced switching, with implications for spintronic devices.
Determinants of emigration and their impact on survival during dispersal in fox and jackal populations
Authors: Kapota Dror , Dolev Amit , Bino Gilad , Yosha Dotan , Guter Amichai , King Roni , Saltz David
Published: April 2016

Animals disperse in response to poor resource conditions as a strategy of escaping harsh competition and stress, but may also disperse under good resource conditions, as these provide better chances of surviving dispersal and gaining fitness benefits such as avoiding kin competition and inbreeding. Individual traits should mediate the effect of resources, yielding a complex condition-dependent dispersal response. We investigated how experimental food reductions in a food-rich environment around poultry-growing villages interact with individual-traits (age, gender, body-mass) in two sympatric canids, red foxes and golden jackals, to jointly affect emigration propensity and survival during dispersal. Sub-adult foxes emigrated more frequently from the food-rich habitat than from the pristine, food-limited habitat, while adult foxes showed the opposite trend. During dispersal, adults exhibited lower survival while sub-adults did not experience additional mortality costs. Although fox mortality rates increased in response to food reduction, dispersal remained unchanged, while jackals showed strong dispersal response in two of the three repetitions. Jackal survival under food reduction was lowest for the dispersing individuals. While resources are an important dispersal determinant, different age classes and species experience the same resource environment differently and consequently have different motivations, yielding different dispersal responses and consequences.
Proteasomes generate spliced epitopes by two different mechanisms and as efficiently as non-spliced epitopes
Authors: Ebstein F. , Textoris-Taube K. , Keller C. , Golnik R. , Vigneron N. , Van den Eynde B. J. , Schuler-Thurner B. , Schadendorf D. , Lorenz F. K. M. , Uckert W. , Urban S. , Lehmann A. , Albrecht-Koepke N. , Janek K. , Henklein P. , Niewienda A. , Kloetzel P. M. , Mishto M.
Published: April 2016

Proteasome-catalyzed peptide splicing represents an additional catalytic activity of proteasomes contributing to the pool of MHC-class I-presented epitopes. We here biochemically and functionally characterized a new melanoma gp100 derived spliced epitope. We demonstrate that the gp100mel47–52/40–42 antigenic peptide is generated in vitro and in cellulo by a not yet described proteasomal condensation reaction. gp100mel47–52/40–42 generation is enhanced in the presence of the β5i/LMP7 proteasome-subunit and elicits a peptide-specific CD8+ T cell response. Importantly, we demonstrate that different gp100mel-derived spliced epitopes are generated and presented to CD8+ T cells with efficacies comparable to non-spliced canonical tumor epitopes and that gp100mel-derived spliced epitopes trigger activation of CD8+ T cells found in peripheral blood of half of the melanoma patients tested. Our data suggest that both transpeptidation and condensation reactions contribute to the frequent generation of spliced epitopes also in vivo and that their immune relevance may be comparable to non-spliced epitopes.
Increased Risk of Psoriasis due to combined effect of HLA-Cw6 and LCE3 risk alleles in Indian population
Authors: Chandra Aditi , Lahiri Anirudhya , Senapati Swapan , Basu Baidehi , Ghosh Saurabh , Mukhopadhyay Indranil , Behra Akhilesh , Sarkar Somenath , Chatterjee Gobinda , Chatterjee Raghunath
Published: April 2016

HLA-Cw6 is one of the most associated alleles in psoriasis. Recently, Late Cornified Envelop 3 (LCE3) genes were identified as a susceptibility factor for psoriasis. Some population showed epistatic interaction of LCE3 risk variants with HLA-Cw6, while some population failed to show any association. We determined the associations of a 32.2 kb deletion comprising LCE3C-3B genes and three SNPs (rs1886734, rs4112788; rs7516108) at the LCE3 gene cluster among the psoriasis patients in India. All three SNPs at the LCE3 gene cluster failed to show any association. In contrary, for patients with HLA-Cw6 allele, all three SNPs and the LCE3C-3B deletion showed significant associations. While, all five LCE3 genes were upregulated in psoriatic skin, only LCE3A showed significant overexpression with homozygous risk genotype compared to the non-risk genotype. LCE3B also showed significant overexpression in patients with HLA-Cw6 allele. Moreover, LCE3A showed significantly higher expression in patients bearing homozygous risk genotype in presence of HLA-Cw6 allele but not in those having non-risk genotype, demonstrating the combined effect of HLA-Cw6 allele and risk associated genotype near LCE3A gene. Integration of genetic and gene expression data thus allowed us to identify the actual disease variants at the LCE3 cluster among the psoriasis patients in India.
Comparison of DNA Quantification Methods for Next Generation Sequencing
Authors: Robin Jérôme D. , Ludlow Andrew T. , LaRanger Ryan , Wright Woodring E. , Shay Jerry W.
Published: April 2016

Next Generation Sequencing (NGS) is a powerful tool that depends on loading a precise amount of DNA onto a flowcell. NGS strategies have expanded our ability to investigate genomic phenomena by referencing mutations in cancer and diseases through large-scale genotyping, developing methods to map rare chromatin interactions (4C; 5C and Hi-C) and identifying chromatin features associated with regulatory elements (ChIP-seq, Bis-Seq, ChiA-PET). While many methods are available for DNA library quantification, there is no unambiguous gold standard. Most techniques use PCR to amplify DNA libraries to obtain sufficient quantities for optical density measurement. However, increased PCR cycles can distort the library’s heterogeneity and prevent the detection of rare variants. In this analysis, we compared new digital PCR technologies (droplet digital PCR; ddPCR, ddPCR-Tail) with standard methods for the titration of NGS libraries. DdPCR-Tail is comparable to qPCR and fluorometry (QuBit) and allows sensitive quantification by analysis of barcode repartition after sequencing of multiplexed samples. This study provides a direct comparison between quantification methods throughout a complete sequencing experiment and provides the impetus to use ddPCR-based quantification for improvement of NGS quality.
Integrated Metabolomics Study of the Milk of Heat-stressed Lactating Dairy Cows
Authors: Tian He , Zheng Nan , Wang Weiyu , Cheng Jianbo , Li Songli , Zhang Yangdong , Wang Jiaqi
Published: April 2016

Heat stress (HS) damages the global dairy industry by reducing milk yields and quality, harming health, and damaging the reproduction of dairy cows, causing huge economic losses each year. However, an understanding of the physiological mechanism of HS lactating dairy cows remains elusive. Here, a metabolomics study using LC-MS and 1H NMR spectroscopy was performed to analyze the metabolomic differences in the milk between HS-free and HS dairy cows, and discover diagnostic biomarkers and changes in the metabolic pathway. A total of 53 discriminating metabolites were significantly up- or down-regulated in the HS group compared with the HS-free group (P < 0.05). These biomarkers were involved in pathways of carbohydrate, amino acid, lipid, and gut microbiome-derived metabolism. Comparing these potential biomarkers with previously identified HS candidate biomarkers in plasma, significant correlations between the levels of lactate, pyruvate, creatine, acetone, β-hydroxybutyrate, trimethylamine, oleic acid, linoleic acid, lysophosphatidylcholine 16:0, and phosphatidylcholine 42:2 in milk and plasma were found, indicating that the blood-milk barrier became leaky and the levels of these 10 biomarkers in milk can reflect HS-induced metabolomic alterations in blood. These novel findings can support more in-depth research to elucidate the milk-based changes in metabolic pathways in HS lactating dairy cows.
Zero gas reference standards
Authors: Miñarro Marta Doval , Brewer Paul J. , Brown Richard J. C. , Persijn Stefan , van Wijk Janneke , Nieuwenkamp Gerard , Baldan Annarita , Kaiser Claire , Sutour Christophe , Macé Tatiana , Škundrić Nikola , Tarhan Tanıl
Published: April 2016

High purity nitrogen or air, often referred to as zero gas, is essential for calibrating instrumentation used in a wide variety of measurements, such as air quality monitoring.
Prospects for point-of-care pathogen diagnostics using surface-enhanced Raman scattering (SERS)
Authors: Granger Jennifer H. , Schlotter Nicholas E. , Crawford Alexis C. , Porter Marc D.
Published: April 2016

This review highlights recent advances in the application of surface-enhanced Raman scattering (SERS) in pathogen detection and discusses many of the challenges in moving this technology to the point-of-care (POC) arena.
Ultra-high Rhodamine B adsorption capacities from an aqueous solution by activated carbon derived from Phragmites australis doped with organic acid by phosphoric acid activation
Authors: Guo Zizhang , Zhang Jian , Liu Hai
Published: April 2016

This study shows that oxalic acid (OA) and succinic acid (SA) were employed to modifyPhragmites australis(PA)-based activated carbons (ACs) during phosphoric acid activation to improve Rhodamine B (RhB) removal from aqueous solutions.
Comparative simulative analysis of single and double stranded truncated octahedral DNA nanocages
Authors: Iacovelli Federico , Falconi Mattia , Knudsen Birgitta R. , Desideri Alessandro
Published: April 2016

Spacefill view of double (DSL) and single (SSL) stranded linkers DNA cages. The blue atoms represent the shared cages scaffold, while the yellow atoms show the single stranded DNA oligonucleotides shaping the double stranded linkers of the DSL cage.
A sensitivity metric and software to guide the analysis of soft films measured by a quartz crystal microbalance
Authors: McNamara Thomas P. , Blanford Christopher F.
Published: April 2016

The TPM-sensitivity metric guides the analysis of viscoelastic thin films studied with a quartz crystal microbalance.
Single-molecule imaging reveals the stoichiometry change of β2-adrenergic receptors by a pharmacological biased ligand
Authors: Sun Yahong , Li Nan , Zhang Mingliang , Zhou Wei , Yuan Jinghe , Zhao Rong , Wu Jimin , Li Zijian , Zhang Youyi , Fang Xiaohong
Published: April 2016

The stoichiometry of β2AR is determined in living cells and the association of β2AR dimerization with biased signalling is revealed.
Ethynide-stabilized high-nuclearity silver(i) sulfido molecular clusters assembled using organic sulfide precursors
Authors: Chen Zi-Yi , Tam Dennis Y. S. , Mak Thomas C. W.
Published: April 2016

Two unprecedented molecular clusters bearing Ag9S6@Ag36 and Ag120S24 cores stabilized by surface ethynide ligands are assembled using novel organic sulfide precursors and structurally characterized by single-crystal X-ray analysis. The figure shows the Ag120S24(PhCC)52 core unit of the latter cluster.
A broken-symmetry density functional study of structures, energies, and protonation states along the catalytic O–O bond cleavage pathway in ba3cytochrome c oxidase from Thermus thermophilus
Authors: Han Du Wen-Ge , Götz Andreas W. , Yang Longhua , Walker Ross C. , Noodleman Louis
Published: April 2016

The [Fea3, CuB] dinuclear center states along the O–O bond cleavage pathway in ba3cytochromecoxidase have been studied using broken-symmetry density functional calculations.
Direct observation of nanoparticle multiple-ring pattern formation during droplet evaporation with dark-field microscopy
Authors: Li Hui , Luo Hao , Zhang Zhen , Li Yongjun , Xiong Bin , Qiao Chunyan , Cao Xuan , Wang Tie , He Yan , Jing Guangyin
Published: April 2016

Highly diluted Au nanorod droplet evaporation and the formation of a multiple-ring pattern on a hydrophobic substrate were observed directly with dark-field microscopy.
Thermal decomposition of graphene oxyradicals under the influence of an embedded five-membered ring
Authors: You Xiaoqing , Wang Hongmiao , Zhang Hong-Bo , Pilling Michael J.
Published: April 2016

In this study, we examined the influence of an embedded five-membered ring on the thermal decomposition of graphene oxyradicals.
Ultrafast spectroscopy, superluminescence and theoretical modeling of a two-photon absorbing fluorene derivative
Authors: Kurhuzenkau S. A. , Woodward A. W. , Yao S. , Belfield K. D. , Shaydyuk Y. O. , Sissa C. , Bondar M. V. , Painelli A.
Published: April 2016

Linear and nonlinear optical properties and photostability of a fluorene derivative are studied and rationalized within essential state models.
Supramolecular 1-D polymerization of DNA origami through a dynamic process at the 2-dimensionally confined air–water interface
Authors: Yonamine Yusuke , Cervantes-Salguero Keitel , Minami Kosuke , Kawamata Ibuki , Nakanishi Waka , Hill Jonathan P. , Murata Satoshi , Ariga Katsuhiko
Published: April 2016

1D polymerization of a DNA origami structure at the 2D air–water interface has been successfully regulated by the Langmuir–Blodgett technique.
Ionic liquid nanostructure enables alcohol self assembly
Authors: Murphy Thomas , Hayes Robert , Imberti Silvia , Warr Gregory G. , Atkin Rob
Published: April 2016

Weakly structured solutions are formed from mixtures of one or more amphiphiles and a polar solvent (usually water), and often contain additional organic components.
Correction: Aromatic cages B420/+: unprecedented existence of octagonal holes in boron clusters
Authors: Tai Truong Ba , Lee Sang Uck , Nguyen Minh Tho
Published: April 2016

Correction for ‘Aromatic cages B420/+: unprecedented existence of octagonal holes in boron clusters’ by Truong Ba Tai et al., Phys. Chem. Chem. Phys., 2016, DOI: 10.1039/c5cp07342a.
Dinickel complexes with anthyridine-based ligands
Authors: Huang Da-Wei , Liu Yi-Hung , Peng Shie-Ming , Liu Shiuh-Tzung
Published: April 2016

Two new dinickel complexes with anthyridine-based ligands and their properties were investigated.
Probing bistability in FeIIand CoIIcomplexes with an unsymmetrically substituted quinonoid ligand
Authors: van der Meer Margarethe , Rechkemmer Yvonne , Breitgoff Frauke D. , Dechert Sebastian , Marx Raphael , Dörfel María , Neugebauer Petr , van Slageren Joris , Sarkar Biprajit
Published: April 2016

A quinone ligand with a [O,O,O,N] donor set is presented. Its FeIIcomplex displays bistability as a function of temperature, pressure and photoexcitation and its CoIIcomplex displays a redox-induced spin-state change.
Method for the production of acrylonitrile–butadiene–styrene (ABS) and polycarbonate (PC)/ABS standards for direct Sb determination in plastics from e-waste using laser-induced breakdown spectroscopy
Authors: Aquino Francisco W. B. , Paranhos Caio M. , Pereira-Filho Edenir R.
Published: April 2016

A procedure for direct Sb determination in solid e-waste samples using ABS and PC/ABS standards containing Sb2O3 is shown. Sb can be used to confirm the presence of PBDEs.
Effects of mono- and divalent metal ions on DNA binding and catalysis of human apurinic/apyrimidinic endonuclease 1
Authors: Miroshnikova Anastasia D. , Kuznetsova Alexandra A. , Vorobjev Yuri N. , Kuznetsov Nikita A. , Fedorova Olga S.
Published: April 2016

Here, we used stopped-flow fluorescence techniques to conduct a comparative kinetic analysis of the conformational transitions in human apurinic/apyrimidinic endonuclease 1 (APE1) and in DNA containing an abasic site in the course of their interaction.
DNA sequence-dependent ionic currents in ultra-small solid-state nanopores
Authors: Comer Jeffrey , Aksimentiev Aleksei
Published: April 2016

Atomic resolution simulations elucidate the effect of DNA sequence and conformation on the ionic current blockades produced by the presence of a DNA strand in an ultra-small solid-state nanopore.
Catalytic stereoselective cascade reactions of quinols with trifluoromethyl ketones: direct access to CF3-containing 1,3-dioxolanes
Authors: Li Feng , Wang Jingjing , Xu Mengmeng , Zhao Xiaobo , Zhou Xiaohong , Zhao Wen-Xian , Liu Lantao
Published: April 2016

A general and efficient synthesis of CF3-containing 1,3-dioxolanes using Et3N-catalyzed ketalization/oxa-Michael cascade of quinols with trifluoromethyl ketones is described. The desired products were obtained in 68%–95% yields with acceptable diastereoselectivities.
A convenient enantioselective CBS-reduction of arylketones in flow-microreactor systems
Authors: De Angelis Sonia , De Renzo Maddalena , Carlucci Claudia , Degennaro Leonardo , Luisi Renzo
Published: April 2016

A convenient, versatile, and green CBS-asymmetric reduction of aryl and heteroaryl ketones has been developed by using the microreactor technology.
Hypervalent iodine(iii)-promoted N-incorporation into N-aryl vinylogous carbamates to quinoxaline diesters: access to 1,4,5,8-tetraazaphenanthrene
Authors: Sagar A. , Vidaycharan Shinde , Shinde Anand H. , Sharada Duddu S.
Published: April 2016

An oxidative N-incorporation strategy for synthesis of quinoxaline diesters under metal-free and mild reaction conditions is described via the formation of two C(sp2)–N bonds utilizing NaN3 as the cheap N-atom source.
Direct functionalization of poly(vinyl chloride) by photo-mediated ATRP without a deoxygenation procedure
Authors: Huang Zhong , Feng Chun , Guo Hao , Huang Xiaoyu
Published: April 2016

A facile and robust strategy of photo-mediated ATRP to directly modify commercial PVC and surfaces of PVC-based materials without any functional group transformation and deoxygenation procedures was reported.
N-(3-(Dimethyl benzyl ammonio)propyl)alkanamide chloride derivatives as corrosion inhibitors for mild steel in 1 M HCl solution: experimental and theoretical investigation
Authors: Shaban Samy M.
Published: April 2016

The effects of the synthesized cationic surfactants corrosion inhibitiors DMBL, DMBM and DMBP on the corrosion of mild carbon steel in acidic medium (1.0 M HCl) were investigated using weight loss and electrochemical measurements.
Influence of dip-coated MgO interphase on the mechanical and dielectric properties of 2D-SiCf/SiC composites
Authors: Hu Yang , Luo Fa , Duan Shichang , Zhou Wancheng , Zhu Dongmei
Published: April 2016

This work focused on the use of the dip-coating process to prepare magnesium oxide (MgO) coatings on silicon carbide fibers (SiCf) as an interfacial system for SiCf/SiC composites.
Simpler and highly sensitive enzyme-free sensing of urea via NiO nanostructures modified electrode
Authors: Arain Munazza , Nafady Ayman , Sirajuddin Sirajuddin , Ibupoto Zafar Hussain , Hussain Sherazi Syed Tufail , Shaikh Tayyaba , Khan Hamayun , Alsalme Ali , Niaz Abdul , Willander Magnus
Published: April 2016

In this study, NiO nanostructures were synthesized via a hydrothermal process using ascorbic acid as doping agent in the presence of ammonia.
Performance and mechanism of hierarchically porous Ce–Zr oxide nanospheres encapsulated calcium alginate beads for fluoride removal from water
Authors: Chen Liang , Zhang Kaisheng , He Junyong , Cai Xing-Guo , Xu Weihong , Liu Jin-Huai
Published: April 2016

Hierarchically porous Ce–Zr metal oxide nanospheres encapsulated calcium alginate millimeter-sized beads showed a high efficiency for fluoride removal from water.
One-step hydrothermal synthesis of hydrophilic Fe3O4/carbon composites and their application in removing toxic chemicals
Authors: Chen Ming , Shao Leng-Leng , Li Jia-Jia , Pei Wei-Jie , Chen Meng-Ke , Xie Xia-Hui
Published: April 2016

Hydrophilic Fe3O4/C nanocomposites have been prepared by a simple one-step hydrothermal reaction route, and demonstrated a high Cr(vi) removal capacity.
Photoelectric properties and potential nitro derivatives sensing by a highly luminescent of Zn(ii) and Cd(ii) metal–organic frameworks assembled by the flexible hexapodal ligand, 1,3,5-triazine-2,4,6-triamine hexaacetic acid
Authors: Li Shuang , Song Jian , Ni Jue Chen , Wang Zhi Nan , Gao Xue , Shi Zhan , Bai Feng Ying , Xing Yong Heng
Published: April 2016

The luminescent quenching of coordination polymers 1 and 2 were especially obvious with the increasing of the nitro derivatives concentration, indicating 1 and 2 have very high sensitivity sensing properties.
Expanding the (cross-)hyperconjugation of 1,4-disilacyclohexa-2,5-dienes to larger monomers and oligomers: a computational investigation
Authors: Denisova Aleksandra V. , Emanuelsson Rikard , Ottosson Henrik
Published: April 2016

DFT calculations are used to study molecules that can be regarded as expanded 1,4-disilacyclohexa-2,5-dienes as well as oligomers based on these or 1,4-disilacyclohexa-2,5-diene with the aim to identify systems with extended (cross)-hyperconjugation.
A unique multi-functional cationic luminescent metal–organic nanotube for highly sensitive detection of dichromate and selective high capacity adsorption of Congo red
Authors: Ding Bin , Guo Chao , Liu Shi Xin , Cheng Yue , Wu Xiang Xia , Su Xiu Mei , Liu Yuan Yuan , Li Yan
Published: April 2016

In this work a flexible multi-dentate 1-(4-aminobenzyl)-1,2,4-triazole (abtz) ligand has been employed, a unique cationic triazole–Ag(i) metal–organic nanotube {[Ag(μ3-abtz)]·(NO3)·(0.125H2O)}n (MONT-1) has been isolated under solvo-thermal conditions.
SBA-15 supported ionic liquid phase (SILP) with H2PW12O40− for the hydrolytic catalysis of red macroalgal biomass to sugars
Authors: Malihan Lenny B. , Nisola Grace M. , Mittal Neha , Lee Seong-Poong , Seo Jeong Gil , Kim Hern , Chung Wook-Jin
Published: April 2016

Efficient sugar production from biomass was achieved using a heterogeneous catalyst SBA-supported ionic liquid phase (SILP) with acidic H2PW12O40−.
Transcriptome-guided discovery and functional characterization of two UDP-sugar 4-epimerase families involved in the biosynthesis of anti-tumor polysaccharides in Ornithogalum caudatum
Authors: Yin Sen , Kong Jian-Qiang
Published: April 2016

A transcriptome-guided discovery and functional identification of UGE and UXE families were presented. Importantly, OcUGE1/2 and OcUXE1 were preliminarily revealed to be responsible for the biosynthesis of anticancer polysaccharides inO. caudatum.
Preparation and characterization of room temperature vulcanized silicone rubber using α-amine ketoximesilanes as auto-catalyzed cross-linkers
Authors: Zhao Qian , Liu Qingyang , Xu Huihui , Bei Yiling , Feng Shengyu
Published: April 2016

A series of α-amine ketoximesilanes were prepared and used as auto-catalyzed cross-linkers in one component room temperature vulcanized (RTV) silicone rubber.
Time-efficient syntheses of nitrogen and sulfur co-doped graphene quantum dots with tunable luminescence and their sensing applications
Authors: Xu Hongbo , Zhou Shenghai , Xiao Lili , Yuan Qunhui , Gan Wei
Published: April 2016

N,S co-doped GQDs with fast preparation and tunable fluorescence were developed and employed as fluorescence probe for selective detection of Fe3+.
One “Click” access to self-complementary molecular modules for halogen bonding
Authors: Cavallo G. , Metrangolo P. , Pilati T. , Resnati G. , Scrivanti A. , Aversa M. , Cariati E.
Published: April 2016

The application of “click chemistry” has proved its efficacy for the construction of novel molecular modules for halogen bonding driven self-assembly.
Preparation of halogenated furfurals as intermediates in the carbohydrates to biofuel process
Authors: Meller Elad , Aviv Avishay , Aizenshtat Zeev , Sasson Yoel
Published: April 2016

Efficient processe for the production of CMF and BMF is demonstrated in a biphasic system of aqueous acid and 1,2-dichloroethane.
Simultaneous adsorptive removal of fluoride and phosphate by magnesia–pullulan composite from aqueous solution
Authors: Ye Yuanyao , Hu Ying , Hussain Zakir , Li Xi , Li Daosheng , Kang Jianxiong
Published: April 2016

The presence of fluoride and phosphate could affect the adsorption rate of another one while simultaneous adsorption on MgOP.
A 2D porous porphyrin-based covalent organic framework for sulfur storage in lithium–sulfur batteries
Authors: Liao Huaping , Wang Hongmin , Ding Huimin , Meng Xiangshi , Xu Hai , Wang Baoshan , Ai Xinping , Wang Cheng
Published: April 2016

A rationally designed porphyrin-based COF has been employed as a host material for sulfur storage in lithium–sulfur batteries.
Design and synthesis of an efficient nanoporous adsorbent for Hg2+ and Pb2+ ions in water
Authors: Li Xiaopan , Bian Chaoqun , Meng Xiangju , Xiao Feng-Shou
Published: April 2016

An efficient nanoporous adsorbent for Hg2+ and Pb2+ ions in water has been rationally synthesized from the interaction of aqueous NaH2C3N3S3 and Na3C3N3S3 solutions. This adsorbent exhibits excellent adsorption capacity and selectivity as well as superior recyclability.
Controllable electrostatic self-assembly of sub-3 nm graphene quantum dots incorporated into mesoporous Bi2MoO6 frameworks: efficient physical and chemical simultaneous co-catalysis for photocatalytic oxidation
Authors: Hao Yuchen , Dong Xiaoli , Wang Xiuying , Zhai Shangru , Ma Hongchao , Zhang Xiufang
Published: April 2016

Over the past few years, the direct assembly of co-catalyst/modification materials into mesoporous photocatalysts has been considered a great challenge.
Synthetic control over intra- and intermolecular charge transfer can turn on the fluorescence emission of non-emissive coumarin
Authors: Jhun Byung Hak , Ohkubo Kei , Fukuzumi Shunichi , You Youngmin
Published: April 2016

Photoinduced charge transfer was exploited in coumarin compounds to obtain strong fluorescence emission.
Crystallographic dependence of internal bias in domain engineered Mn-doped relaxor-PbTiO3 single crystals
Authors: Luo Nengneng , Zhang Shujun , Li Qiang , Yan Qingfeng , Zhang Yiling , Ansell Troy , Luo Jun , Shrout Thomas R.
Published: April 2016

Unique properties have been obtained by defect dipole engineering in relaxor-PT single crystals.
Non-canonical dynamic mechanisms of interaction between the p66Shc protein and Met receptor
Authors: Landry Mélissa , Pomerleau Véronique , Saucier Caroline
Published: April 2016

Met receptor tyrosine kinase (RTK) is known to bind to the three distinct protein isoforms encoded by the ShcA (Shc) gene. Structure–function studies have unveiled critical roles for p52Shc-dependent signalling pathways in Met-regulated biological functions. The molecular basis of the interaction between the Met and p52Shc proteins is well-defined, but not for the longest protein isoform, p66Shc. In the present study, co-immunoprecipitation assays were performed in human embryonic kidney 293 (HEK293) cells, transiently co-transfected with Met and p66Shc mutants, in order to define the molecular determinants involved in mediating Met–p66Shc interaction. Our results show that p66Shc interacts constitutively with the receptor Met, and the Grb2 (growth factor receptor-bound protein-2) and Gab1 (Grb2-associated binder-1) adaptor proteins. Although its phosphotyrosine-binding domain (PTB) and Src homology 2 (SH2) domains co-ordinate p66Shc binding to non-activated Met receptor, these phosphotyrosine-binding modules, and its collagen homology domain 2 (CH2) region, exert negative constraints. In contrast, p66Shc interaction with the activated Met depends mainly on the integrity of its PTB domain, and to a lesser extent of its SH2 domain. Even though not required for the recruitment of p66Shc, tyrosine phosphorylation of p66Shc by activated Met enhances these interactions by mechanisms not reliant on the integrity of the Met multisubstrate-binding site. In turn, this increases phosphotyrosine-dependent p66Shc–Grb2–Gab1 complex formation away from the receptor, while blocking Grb2 and Gab1 recruitment to activated Met. In conclusion, we identify, for the first time, a novel non-canonical dynamic mode of interaction between Met and the p66 protein isoform of Shc and its effects on rewiring binding effector complexes according to the activation state of the receptor.
Splenic release of platelets contributes to increased circulating platelet size and inflammation after myocardial infarction
Authors: Gao Xiao-Ming , Moore Xiao-Lei , Liu Yang , Wang Xin-Yu , Han Li-Ping , Su Yidan , Tsai Alan , Xu Qi , Zhang Ming , Lambert Gavin W. , Kiriazis Helen , Gao Wei , Dart Anthony M. , Du Xiao-Jun
Published: April 2016

Acute myocardial infarction (AMI) is characterized by a rapid increase in circulating platelet size but the mechanism for this is unclear. Large platelets are hyperactive and associated with adverse clinical outcomes. We determined mean platelet volume (MPV) and platelet–monocyte conjugation (PMC) using blood samples from patients, and blood and the spleen from mice with AMI. We further measured changes in platelet size, PMC, cardiac and splenic contents of platelets and leucocyte infiltration into the mouse heart. In AMI patients, circulating MPV and PMC increased at 1–3 h post-MI and MPV returned to reference levels within 24 h after admission. In mice with MI, increases in platelet size and PMC became evident within 12 h and were sustained up to 72 h. Splenic platelets are bigger than circulating platelets in normal or infarct mice. At 24 h post-MI, splenic platelet storage was halved whereas cardiac platelets increased by 4-fold. Splenectomy attenuated all changes observed in the blood, reduced leucocyte and platelet accumulation in the infarct myocardium, limited infarct size and alleviated cardiac dilatation and dysfunction. AMI-induced elevated circulating levels of adenosine diphosphate and catecholamines in both human and the mouse, which may trigger splenic platelet release. Pharmacological inhibition of angiotensin-converting enzyme, β1-adrenergic receptor or platelet P2Y12 receptor reduced platelet abundance in the murine infarct myocardium albeit having diverse effects on platelet size and PMC. In conclusion, AMI evokes release of splenic platelets, which contributes to the increase in platelet size and PMC and facilitates myocardial accumulation of platelets and leucocytes, thereby promoting post-infarct inflammation.
The line tension of two-dimensional ionic fluids
Authors: Eustaquio-Armenta María del Rosario , Méndez-Maldonado Gloria Arlette , González-Melchor Minerva
Published: April 2016

Pressure tensor components are very useful in the calculation of the tension associated with a liquid-vapor interface. In this work, we present expressions for the pressure tensor components of two-dimensional ionic fluids, modeled at the level of the primitive model. As an application, we carried out molecular dynamics simulations of liquid-vapor interfaces to calculate the line tension of the 1:1 two-dimensional ionic fluid, whose liquid-vapor coexistence curve had already been obtained in a previous work. The pressure tensor components were validated by simulating states of one phase and reproducing the scalar pressure, previously obtained from bulk simulations and reported in the literature. The effects on the line tension and the coexisting densities, originated by the choice of the Ewald parameters, the cutoff radius, and the interfacial length were also evaluated.
Phase behaviour of self-assembled monolayers controlled by tuning physisorbed and chemisorbed states: A lattice-model view
Authors: Fortuna Sara , Cheung David L. , Johnston Karen
Published: April 2016

The self-assembly of molecules on surfaces into 2D structures is important for the bottom-up fabrication of functional nanomaterials, and the self-assembled structure depends on the interplay between molecule-molecule interactions and molecule-surface interactions. Halogenated benzene derivatives on platinum have been shown to have two distinct adsorption states: a physisorbed state and a chemisorbed state, and the interplay between the two can be expected to have a profound effect on the self-assembly and phase behaviour of these systems. We developed a lattice model that explicitly includes both adsorption states, with representative interactions parameterised using density functional theory calculations. This model was used in Monte Carlo simulations to investigate pattern formation of hexahalogenated benzene molecules on the platinum surface. Molecules that prefer the physisorbed state were found to self-assemble with ease, depending on the interactions between physisorbed molecules. In contrast, molecules that preferentially chemisorb tend to get arrested in disordered phases. However, changing the interactions between chemisorbed and physisorbed molecules affects the phase behaviour. We propose functionalising molecules in order to tune their adsorption states, as an innovative way to control monolayer structure, leading to a promising avenue for directed assembly of novel 2D structures.
The necking time of gas bubbles in liquids of arbitrary viscosity
Authors: Bolaños-Jiménez R. , Sevilla A. , Martínez-Bazán C.
Published: April 2016

We report an experimental and theoretical study of the collapse time of a gas bubble injected into an otherwise stagnant liquid under quasi-static conditions and for a wide range of liquid viscosities. The experiments were performed by injecting a constant flow rate of air through a needle with inner radius a into several water/glycerine mixtures, providing a viscosity range of 20 cP ≲ μ ≲ 1500 cP. By analyzing the temporal evolution of the neck radius, R0(t), the collapse time has been extracted for three different stages during the collapse process, namely, Ri/a = 0.6, 0.4, and 0.2, being Ri = R0(t = 0) the initial neck radius. The collapse time is shown to monotonically increase with both Ri/a and with the Ohnesorge number, Oh=μ/ρσRi, where ρ and σ represent the liquid density and the surface tension coefficient, respectively. The theoretical approach is based on the cylindrical Rayleigh-Plesset equation for the radial liquid flow around the neck, which is the appropriate leading-order representation of the collapse dynamics, thanks to the slenderness condition R0(t) r1(t) ≪ 1, where r1(t) is half the axial curvature of the interface evaluated at the neck. The Rayleigh-Plesset equation can be integrated numerically to obtain the collapse time, τcol, which is made dimensionless using the capillary time, tσ=ρRi3/σ. We present a novel scaling law for τcol as a function of Ri/a and Oh that closely follows the experimental data for the entire range of both parameters, and provide analytical expressions in the inviscid and Stokes regimes, i.e., τcol(Oh→0)→2lnC and τcol(Oh → ∞) → 2Oh, respectively, where C is a constant of order unity that increases with Ri/a.
Invited Review Article: Review of post-process optical form metrology for industrial-grade metal additive manufactured parts
Authors: Stavroulakis P. I. , Leach R. K.
Published: April 2016

The scope of this review is to investigate the main post-process optical form measurement technologies available in industry today and to determine whether they are applicable to industrial-grade metal additive manufactured parts. An in-depth review of the operation of optical three-dimensional form measurement technologies applicable to metal additive manufacturing is presented, with a focus on their fundamental limitations. Looking into the future, some alternative candidate measurement technologies potentially applicable to metal additive manufacturing will be discussed, which either provide higher accuracy than currently available techniques but lack measurement volume, or inversely, which operate in the appropriate measurement volume but are not currently accurate enough to be used for industrial measurement.
On solutions of Maxwell’s equations with dipole sources over a thin conducting film
Authors: Margetis Dionisios , Luskin Mitchell
Published: April 2016

We derive and interpret solutions of time-harmonic Maxwell’s equations with a vertical and a horizontal electric dipole near a planar, thin conducting film, e.g., graphene sheet, lying between two unbounded isotropic and non-magnetic media. Exact expressions for all field components are extracted in terms of rapidly convergent series of known transcendental functions when the ambient media have equal permittivities and both the dipole and observation point lie on the plane of the film. These solutions are simplified for all distances from the source when the film surface resistivity is large in magnitude compared to the intrinsic impedance of the ambient space. The formulas reveal the analytical structure of two types of waves that can possibly be excited by the dipoles and propagate on the film. One of these waves is intimately related to the surface plasmon-polariton of transverse-magnetic polarization of plane waves.