bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative analyses of whole-genome protein sequences from multiple organisms
Authors: Yokono Makio , Satoh Soichirou , Tanaka Ayumi
Published: April 2018

Phylogenies based on entire genomes are a powerful tool for reconstructing the Tree of Life. Several methods have been proposed, most of which employ an alignment-free strategy. Average sequence similarity methods are different than most other whole-genome methods, because they are based on local alignments. However, previous average similarity methods fail to reconstruct a correct phylogeny when compared against other whole-genome trees. In this study, we developed a novel average sequence similarity method. Our method correctly reconstructs the phylogenetic tree of in silico evolved E. coli proteomes. We applied the method to reconstruct a whole-proteome phylogeny of 1,087 species from all three domains of life, Bacteria, Archaea, and Eucarya. Our tree was automatically reconstructed without any human decisions, such as the selection of organisms. The tree exhibits a concentric circle-like structure, indicating that all the organisms have similar total branch lengths from their common ancestor. Branching patterns of the members of each phylum of Bacteria and Archaea are largely consistent with previous reports. The topologies are largely consistent with those reconstructed by other methods. These results strongly suggest that this approach has sufficient taxonomic resolution and reliability to infer phylogeny, from phylum to strain, of a wide range of organisms.
Weighted Multi-marker Genetic Risk Scores for Incident Coronary Heart Disease among Individuals of African, Latino and East-Asian Ancestry
Authors: Iribarren Carlos , Lu Meng , Jorgenson Eric , Martínez Manuel , Lluis-Ganella Carla , Subirana Isaac , Salas Eduardo , Elosua Roberto
Published: April 2018

We examined the clinical utility of two multi-locus genetic risk scores (GRSs) previously validated in Europeans among persons of African (AFR; n = 2,089), Latino (LAT; n = 4,349) and East-Asian (EA; n = 4,804) ancestry. We used data from the GERA cohort (30–79 years old, 68 to 73% female). We utilized two GRSs with 12 and 51 SNPs, respectively, and the Framingham Risk Score (FRS) to estimate 10-year CHD risk. After a median 8.7 years of follow-up, 450 incident CHD events were documented (95 in AFR, 316 in LAT and 39 EA, respectively). In a model adjusting for principal components and risk factors, tertile 3 vs. tertile 1 of GRS_12 was associated with 1.86 (95% CI, 1.15–3.01), 1.52 (95% CI, 1.02–2.25) and 1.19 (95% CI, 0.77–1.83) increased hazard of CHD in AFR, LAT and EA, respectively. Inclusion of the GRSs in models containing the FRS did not increase the C-statistic but resulted in net overall reclassification of 10% of AFR, 7% LAT and EA and in reclassification of 13% of AFR and EA as well as 10% LAT in the intermediate FRS risk subset. Our results support the usefulness of incorporating genetic information into risk assessment for primary prevention among minority subjects in the U.S.
Elevated expression of human bHLH factor ATOH7 accelerates cell cycle progression of progenitors and enhances production of avian retinal ganglion cells
Authors: Zhang Xiang-Mei , Hashimoto Takao , Tang Ronald , Yang Xian-Jie
Published: April 2018

The production of vertebrate retinal projection neurons, retinal ganglion cells (RGCs), is regulated by cell-intrinsic determinants and cell-to-cell signaling events. The basic-helix-loop-helix (bHLH) protein Atoh7 is a key neurogenic transcription factor required for RGC development. Here, we investigate whether manipulating human ATOH7 expression among uncommitted progenitors can promote RGC fate specification and thus be used as a strategy to enhance RGC genesis. Using the chicken retina as a model, we show that cell autonomous expression of ATOH7 is sufficient to induce precocious RGC formation and expansion of the neurogenic territory. ATOH7 overexpression among neurogenic progenitors significantly enhances RGC production at the expense of reducing the progenitor pool. Furthermore, forced expression of ATOH7 leads to a minor increase of cone photoreceptors. We provide evidence that elevating ATOH7 levels accelerates cell cycle progression from S to M phase and promotes cell cycle exit. We also show that ATOH7-induced ectopic RGCs often exhibit aberrant axonal projection patterns and are correlated with increased cell death during the period of retinotectal connections. These results demonstrate the high potency of human ATOH7 in promoting early retinogenesis and specifying the RGC differentiation program, thus providing insight for manipulating RGC production from stem cell-derived retinal organoids.
Children passively allow other’s rule violations in cooperative situations
Authors: Ikeda Ayaka , Okumura Yuko , Kobayashi Tessei , Itakura Shoji
Published: April 2018

Recent studies in developmental psychology have revealed the developmental origins of cooperation. Although such studies regard cooperation as a pro-social behavior, studies on adults have found a negative aspect: cooperation sometimes promotes unethical behavior. Adults also exhibit altruistic cheating, even though their cheating might not actually benefit them. However, the development of negative aspects of cooperation remains unclear. Our study examined whether 7-year-old children engage in negative aspects of cooperation from two aspects using a peeking paradigm. Specifically, Experiment 1 examined children’s negative aspects of cooperation from the perspective of collaboration and Experiment 2 examined altruistic behavior. Results of Experiment 1 revealed that children kept the cheating of a collaborative partner secret even though they did not actively cheat themselves. In Experiment 2, children also kept the partner’s cheating secret even when violations did not provide any reward to themselves, if the predefined reward was high. In contrast, children did not keep the cheating secret if the predefined reward was low. Overall, our findings suggest that even 7-year-olds tend to act as if cooperating is more important than following rules that are compatible and exhibit negative aspects of cooperation.
Scandium doping brings speed improvement in Sb2Te alloy for phase change random access memory application
Authors: Chen Xin , Zheng Yonghui , Zhu Min , Ren Kun , Wang Yong , Li Tao , Liu Guangyu , Guo Tianqi , Wu Lei , Liu Xianqiang , Cheng Yan , Song Zhitang
Published: April 2018

Phase change random access memory (PCRAM) has gained much attention as a candidate for nonvolatile memory application. To develop PCRAM materials with better properties, especially to draw closer to dynamic random access memory (DRAM), the key challenge is to research new high-speed phase change materials. Here, Scandium (Sc) has been found it is helpful to get high-speed and good stability after doping in Sb2Te alloy. Sc0.1Sb2Te based PCRAM cell can achieve reversible switching by applying even 6 ns voltage pulse experimentally. And, Sc doping not only promotes amorphous stability but also improves the endurance ability comparing with pure Sb2Te alloy. Moreover, according to DFT calculations, strong Sc-Te bonds lead to the rigidity of Sc centered octahedrons, which may act as crystallization precursors in recrystallization process to boost the set speed.
Accurate estimation of a phase diagram from a single STM image
Authors: Takeuchi Kazuhito , Yuge Koretaka , Tabata Shinya , Saito Hiroki , Kurokawa Shu , Sakai Akira
Published: April 2018

We propose a new approach to constructing a phase diagram using the effective Hamiltonian derived only from a single real-space image produced by scanning tunneling microscopy (STM). Currently, there have been two main methods to construct phase diagrams in material science: ab initio calculations and CALPHAD with thermodynamic information obtained by experiments and/or theoretical calculations. Although the two methods have successfully revealed a number of unsettled phase diagrams, their results sometimes contradicted when it is difficult to construct an appropriate Hamiltonian that captures the characteristics of materials, e.g., for a system consisting of multiple-scale objects whose interactions are essential to the system’s characteristics. Meanwhile, the advantage of our approach over existing methods is that it can directly and uniquely determine the effective Hamiltonian without any thermodynamic information. The validity of our approach is demonstrated through an Mg–Zn–Y long-period stacking-ordered structure, which is a challenging system for existing methods, leading to contradictory results. Our result successfully reproduces the ordering tendency seen in STM images that previous theoretical study failed to reproduce and clarifies its previously unknown phase diagram. Thus, our approach can be used to clear up contradictions shown by existing methods.
Transplantation of human microbiota into conventional mice durably reshapes the gut microbiota
Authors: Wrzosek Laura , Ciocan Dragos , Borentain Patrick , Spatz Madeleine , Puchois Virginie , Hugot Cindy , Ferrere Gladys , Mayeur Camille , Perlemuter Gabriel , Cassard Anne-Marie
Published: April 2018

Human microbiota-associated (HMA) mice are an important model to study the relationship between liver diseases and intestinal microbiota. We describe a new method to humanize conventional mice based on bowel cleansing with polyethylene glycol followed by fecal microbiota transplantation (FMT) from a human donor. Four successive bowel cleansings were sufficient to empty the intestine and decrease the microbiota by 90%. We then compared four different strategies based on the frequency of FMT over four weeks: (1) twice a week; (2) once a week; (3) two FMTs; (4) one FMT. We were able to transfer human bacteria to mice, irrespective of the strategy used. We detected human bacteria after four weeks, even if only one FMT was performed, but there was a shift of the microbiota over time. FMT twice a week for four weeks was too frequent and perturbed the stability of the newly formed ecosystem. FMT once a week appears to be the best compromise as it allowed engraftment of Faecalibacterium, and a higher diversity of bacteria belonging to the Bacteroidales order. Our easy to establish HMA mouse model could be used as an alternative to classical HMA mice to study the relationship between the liver and the microbiota.
Increased experimental conditions and marker densities identified more genetic loci associated with southern and northern leaf blight resistance in maize
Authors: Li Yong-xiang , Chen Lin , Li Chunhui , Bradbury Peter J. , Shi Yun-su , Song Yanchun , Zhang Dengfeng , Zhang Zhiwu , Buckler Edward S. , Li Yu , Wang Tianyu
Published: April 2018

Southern leaf blight (SLB) and northern leaf blight (NLB) are the two major foliar diseases limiting maize production worldwide. Upon previous study with the nested association mapping (NAM) population, which consist of 5,000 recombinant inbred lines from 25 parents crossed with B73, we expanded the phenotyping environments from the United States (US) to China, and increased the marker densities from 1106 to 7386 SNPs for linkage mapping, and from 1.6 to 28.5 million markers for association mapping. We identified 49 SLB and 48 NLB resistance-related unique QTLs in linkage mapping, and multiple loci in association mapping with candidate genes involved in known plant disease-resistance pathways. Furthermore, an independent natural population with 282 diversified inbred lines were sequenced for four candidate genes selected based on their biological functions. Three of them demonstrated significant associations with disease resistance. These findings provided valuable resources for further implementations to develop varieties with superior resistance for NLB and SLB.
Rest-related consolidation protects the fine detail of new memories
Authors: Craig Michael , Dewar Michaela
Published: April 2018

Newly encoded memories are labile and consolidate over time. The importance of sleep in memory consolidation has been well known for almost a decade. However, recent research has shown that awake quiescence, too, can support consolidation: people remember more new memories if they quietly rest after encoding than if they engage in a task. It is not yet known how exactly this rest-related consolidation benefits new memories, and whether it affects the fine detail of new memories. Using a sensitive picture recognition task, we show that awake quiescence aids the fine detail of new memories. Young adults were significantly better at discriminating recently encoded target pictures from similar lure pictures when the initial encoding of target pictures had been followed immediately by 10 minutes of awake quiescence than an unrelated perceptual task. This novel finding indicates that, in addition to influencing how much we remember, our behavioural state during wakeful consolidation determines, at least in part, the level of fine detail of our new memories. Thus, our results suggest that rest-related consolidation protects the fine detail of new memories, allowing us to retain detailed memories.
Structural insights from lipid-bilayer nanodiscs link α-Synuclein membrane-binding modes to amyloid fibril formation
Authors: Viennet Thibault , Wördehoff Michael M. , Uluca Boran , Poojari Chetan , Shaykhalishahi Hamed , Willbold Dieter , Strodel Birgit , Heise Henrike , Buell Alexander K. , Hoyer Wolfgang , Etzkorn Manuel
Published: April 2018

The protein α-Synuclein (αS) is linked to Parkinson’s disease through its abnormal aggregation, which is thought to involve cytosolic and membrane-bound forms of αS. Following previous studies using micelles and vesicles, we present a comprehensive study of αS interaction with phospholipid bilayer nanodiscs. Using a combination of NMR-spectroscopic, biophysical, and computational methods, we structurally and kinetically characterize αS interaction with different membrane discs in a quantitative and site-resolved way. We obtain global and residue-specific αS membrane affinities, and determine modulations of αS membrane binding due to αS acetylation, membrane plasticity, lipid charge density, and accessible membrane surface area, as well as the consequences of the different binding modes for αS amyloid fibril formation. Our results establish a structural and kinetic link between the observed dissimilar binding modes and either aggregation-inhibiting properties, largely unperturbed aggregation, or accelerated aggregation due to membrane-assisted fibril nucleation.
DARPP-32 and t-DARPP promote non-small cell lung cancer growth through regulation of IKKα-dependent cell migration
Authors: Alam Sk. Kayum , Astone Matteo , Liu Ping , Hall Stephanie R. , Coyle Abbygail M. , Dankert Erin N. , Hoffman Dane K. , Zhang Wei , Kuang Rui , Roden Anja C. , Mansfield Aaron S. , Hoeppner Luke H.
Published: April 2018

Lung cancer is the leading cause of cancer-related death worldwide. Here we demonstrate that elevated expression of dopamine and cyclic adenosine monophosphate-regulated phosphoprotein, Mr 32000 (DARPP-32), and its truncated splice variant t-DARPP promote lung tumor growth, while abrogation of DARPP-32 expression in human non-small-cell lung cancer (NSCLC) cells reduces tumor growth in orthotopic mouse models. We observe a physical interaction between DARPP-32 and inhibitory kappa B kinase-α (IKKα) that promotes NSCLC cell migration through non-canonical nuclear factor kappa-light-chain-enhancer of activated B cells 2 (NF-κB2) signaling. Bioinformatics analysis of 513 lung adenocarcinoma patients reveals that elevated t-DARPP isoform expression is associated with poor overall survival. Histopathological investigation of 62 human lung adenocarcinoma tissues also shows that t-DARPP expression is elevated with increasing tumor (T) stage. Our data suggest that DARPP-32 isoforms serve as a negative prognostic marker associated with increasing stages of NSCLC and may represent a novel therapeutic target.
Molecularly Imprinted Polymer-based Materials for Quantifying Pharmaceuticals
Authors: Maciejewska D. , Sobiech M. , Luliński P.
Published: April 2018

Synthetic polymers possessing cavities designed for a target analyte (named molecularly imprinted polymers, MIPs) are used for the development of various analytical procedures. MIPs are used in the different steps of the methods including extraction and cleanup of analytes, as well as analysis of matrix effects. Basically, the analytes adsorbed by appropriate imprinted polymers in off-line or in on-line systems are eluted and detected directly using different analytical techniques or in combination with other separation techniques or sensors. Many procedures dealing with MIPs have been successfully elaborated and extensively reviewed. This chapter focuses on the commercially available MIP sorbents and the patented MIPs dedicated to the determination of pharmaceuticals. Additionally, some details of analytical procedures are presented for the isolation of pharmaceuticals from complex matrices.
Molecularly Imprinted Polymer-based Optical Chemosensors for Selective Chemical Determinations
Authors: Moreno-Bondi M. C. , Benito-Peña E. , Carrasco S. , Urraca J. L.
Published: April 2018

Molecular imprinting is able to provide essential analyte recognition without the limitations of biomolecules. These human-made materials have emerged as artificial sensing units for the development of optical sensors, potentially replacing antibodies, enzymes or other biological receptors. They are characterized by low production costs, stability, format adaptability and the possibility to imprint, and thus the ability to recognize, a wide variety of target molecules. MIP-based chemosensors can be interrogated using different optical techniques including UV-vis, infrared, fluorescence, chemiluminescence, surface plasmon resonance (SPR) or surface-enhanced Raman scattering (SERS) spectroscopy. This chapter summarizes the main developments and applications of MIPs in the area of optical sensors, with special emphasis on their analytical applications over the past five years.
Molecularly Imprinted Polymer Sensor Arrays
Authors: Li Ping , Richardson William J. , Song Di , Shimizu Ken D.
Published: April 2018

This chapter provides an updated review of research about chemosensor arrays and assays assembled from molecularly imprinted polymers (MIPs) and imprinted materials. The molecular imprinting process provides rapid and inexpensive access to tailorable molecular recognition elements for sensing applications. However, chemosensors based on individual MIPs typically reveal low selectivity and high cross-reactivity. Assembling multiple MIPs into an array presents a convenient and effective solution to this problem. The binding pattern of each analyte to an array of MIPs can provide a unique fingerprint which can be classified using multivariate pattern recognition algorithms. In this chapter, key aspects in designing and developing MIP sensor arrays will be discussed, including the choice of template and monomer, polymer matrix and morphology, signaling mechanisms, and statistical data analysis. Selected examples from the literature are presented to highlight unique advantages and applications of the MIP chemosensor array as well as future problems and challenges.
Effect of geometrical constraints on human pluripotent stem cell nuclei in pluripotency and differentiation
Authors: Grespan Eleonora , Giobbe Giovanni G. , Badique Florent , Anselme Karine , Rühe Jürgen , Elvassore Nicola
Published: April 2018

Pluripotent stem cells are differentiated on microstructured substrates to investigate the nuclear deformability during differentiation and the role of mechanoregulating proteins.
One-pot synthesis of Pd@Pt3Ni core–shell nanobranches with ultrathin Pt3Ni{111} skins for efficient ethanol electrooxidation
Authors: Wang Yuanyuan , Wang Wei , Xue Fei , Cheng Yong , Liu Kai , Zhang Qiaobao , Liu Maochang , Xie Shuifen
Published: April 2018

Pd@Pt3Ni core–shell nanobranches with ultrathin Pt3Ni{111} skins were facilely synthesized in one-pot and exhibited outstanding performances for ethanol electrooxidation.
Adenine–thymine tautomerization under the influence of strong homogeneous electric fields
Authors: Arabi Alya A. , Matta Chérif F.
Published: April 2018

This paper reveals the key energy correction terms contributing to the low probability of AT tautomerization under electric fields.
Magnetic field effects on coenzyme B12- and B6-dependent lysine 5,6-aminomutase: switching of the J-resonance through a kinetically competent radical-pair intermediate
Authors: Chen Jun-Ru , Ke Shyue-Chu
Published: April 2018

External magnetic fields interact with lysine 5,6-aminomutase, through an immobilized radical-pair with constant and large exchange interaction, to switch on J-resonance between singlet and triplet spin states, which have different reactive fates.
Novel chelators based on adamantane-derived semicarbazones and hydrazones that target multiple hallmarks of Alzheimer's disease
Authors: Palanimuthu Duraippandi , Wu Zhixuan , Jansson Patric J. , Braidy Nady , Bernhardt Paul V. , Richardson Des R. , Kalinowski Danuta S.
Published: April 2018

Novel adamantane-derived semicarbazones and hydrazones show multi-functional activity as potential therapeutics for Alzheimer's disease.
5-Methyl-2-thienylcalcium iodide
Authors: Koch Alexander , Krieck Sven , Görls Helmar , Westerhausen Matthias
Published: April 2018

Several preconditions are required to allow a high-yield synthesis of 2-thienylcalcium halide including protection of the 5-position by a methyl group and formation of a tetrahydropyran adduct.
Electrochemical oxidation of ciprofloxacin in two different processes: the electron transfer process on the anode surface and the indirect oxidation process in bulk solutions
Authors: Shen Bo , Wen Xianghua , Korshin Gregory V.
Published: April 2018

Two typical electrochemical processes, including direct electron transfer and indirect oxidation, were investigated with ciprofloxacin as a target compound.
Improved NOx reduction in the presence of alkali metals by using hollandite Mn–Ti oxide promoted Cu-SAPO-34 catalysts
Authors: Zha Kaiwen , Kang Lin , Feng Chong , Han Lupeng , Li Hongrui , Yan Tingting , Maitarad Phornphimon , Shi Liyi , Zhang Dengsong
Published: April 2018

Hollandite Mn–Ti oxide promoted Cu-SAPO-34 catalysts exhibited outstanding deNOx performance and excellent resistance against alkali metal poisoning.
New reactions and processes for the efficient synthesis of a HCV NS5b prodrug
Authors: Orr Robert K. , McCabe Dunn Jamie M. , Nolting Andrew , Hyde Alan M. , Ashley Eric R. , Leone Joseph , Sirota Eric , Jurica Jon A. , Gibson Andrew , Wise Christopher , Oliver Steven , Ruck Rebecca T.
Published: April 2018

The evolution of synthetic chemistry approaches towards a green and sustainable synthesis of a HCV NS5b cyclic prodrug nucleoside (CPN) is described.
NMR spectroscopy: a potent tool for studying monolayer-protected metal nanoclusters
Authors: Salassa G. , Bürgi T.
Published: April 2018

NMR spectroscopy is a powerful tool to study the structure, dynamics and interactions of monolayer protected metal clusters.
Incorporation of Fmoc-Y nanofibers into Ca-alginate hydrogels for improving their mechanical properties and the controlled release of small molecules
Authors: Chen Jiahui , Tao Na , Fang Shiqi , Chen Zewen , Liang Li , Sun Xiaoyi , Li Juan , Liu You-Nian
Published: April 2018

A robust interpenetrating network (IPN) hydrogel was assembled from calcium alginate and Fmoc-tyrosine for the controlled release of small molecules.
Synthesis, characterization, and thermal properties of cobalt(ii) compounds with guanidinate ligands
Authors: Zhang Yuxiang , Du Liyong , Liu Xinfang , Ding Yuqiang
Published: April 2018

The synthesis, characterization, and thermal properties of cobalt(ii) compounds with guanidinate ligands and their potential as CVD precursors are reported.
Role of the puckered anisotropic surface in the surface and adsorption properties of black phosphorus
Authors: Lazar Petr , Otyepková Eva , Pykal Martin , Čépe Klára , Otyepka Michal
Published: April 2018

The structure of phosphorene resembles the honeycomb arrangement of graphene, but its layers are buckled and highly anisotropic.
Fabricating highly luminescent solid hybrids based on silicon nanoparticles: a simple, versatile and green method
Authors: Huang Jingchun , Li Qi , Shao Zhengzhong
Published: April 2018

In this work, we report a simple but novel method to transfer highly luminescent silicon nanoparticles (Si NPs) from solutions to solids without sacrificing their excellent photoluminescence (PL) properties.
Quantum dot–polymer conjugates for stable luminescent displays
Authors: Ghimire Sushant , Sivadas Anjaly , Yuyama Ken-ichi , Takano Yuta , Francis Raju , Biju Vasudevanpillai
Published: April 2018

The broad absorption of light in the UV-Vis-NIR region and the size-based tunable photoluminescence color of semiconductor quantum dots make these tiny crystals one of the most attractive antennae in solar cells and phosphors in electrooptical devices.
Neighboring phenolic group-activated gem-difluoroallylboration of imines for the catalyst-free synthesis of gem-difluorohomoallylamines
Authors: Yang Xing , Zhang Feng , Zhou Yang , Huang Yi-Yong
Published: April 2018

An unprecedented imine allylation with pinacol gem-difluoroallylborates for the synthesis of a wide range of racemic gem-difluorohomoallylamine derivatives under catalyst-free conditions was enabled by a neighboring phenolic group in an N-protecting group.
A Rh(iii)-catalyzed redox-neutral C–H alkylation reaction with allylic alcohols by using a traceless oxidizing directing group
Authors: Wang Yubo , Chen Yu , Yang Yaxi , Zhou Bing
Published: April 2018

A Rh(iii)-catalyzed C–H alkylation of N-phenoxyacetamides with allylic alcohols has been developed to provide valuable β-aryl ketones under mild and redox-neutral conditions by using a traceless oxidizing directing group.
Tandem blocking of PCR extension to form a single-stranded overhang for facile, visual, and ultrasensitive gene detection
Authors: Sui Zhe , Li Tong , An Ran , Wu Wei , Komiyama Makoto , Liang Xingguo
Published: April 2018

Here we present a simple but practically useful assay for gene detection. This strategy employs the advantages of both PCR and Au colloidal science, and thus satisfactorily fulfills the factors required for Point-of-Care detection.
Effect of Bi2O3content on the microstructure and electrical properties of SrBi2Nb2O9piezoelectric ceramics
Authors: He Xiaochun , Chu Ruiqing , Xu Zhijun , Yao Zhongran , Hao Jigong
Published: April 2018

Lead-free ceramics, SrBi2Nb2O9–xBi2O3(SBN–xBi), with different Bi contents of which the molar ratio,n(Sr) : n(Bi) : n(Nb), is 1 : 2(1 +x/2) : 2 (x= −0.05, 0.0, 0.05, 0.10), were prepared by conventional solid-state reaction method.
Thermosensitive star polymer pompons with a core–arm structure as thermo-responsive controlled release drug carriers
Authors: Xu Na , Huang Xiaobei , Yin Guangfu , Bu Meijiao , Pu Ximing , Chen Xianchun , Liao Xiaoming , Huang Zhongbing
Published: April 2018

Herein, a thermosensitive star polymer pompon with a core–arm structure was synthesized using a grafting-on method as a thermo-responsive controlled release drug carrier.
Nanolayer-like-shaped MgFe2O4 synthesised via a simple hydrothermal method and its catalytic effect on the hydrogen storage properties of MgH2
Authors: Ali N. A. , Idris Nurul Hayati , Din M. F. Md , Mustafa N. S. , Sazelee N. A. , Halim Yap F. A. , Sulaiman N. N. , Yahya M. S. , Ismail M.
Published: April 2018

The nanolayer-like-shaped MgFe2O4-added MgH2 composite showed an improvement in de/absorption properties compared to that of un-doped MgH2.
Diastereoselective construction of 4-indole substituted chromans bearing a ketal motif through a three-component Friedel–Crafts alkylation/ketalization sequence
Authors: Guo Jiao-Mei , Wang Wen-Bo , Guo Jia , Zhu Yan-Shuo , Bai Xu-Guan , Jin Shao-Jing , Wang Qi-Lin , Bu Zhan-Wei
Published: April 2018

The first TfOH-catalyzed three-component Friedel–Crafts alkylation/ketalization sequence of indoles, alcohols and ortho-hydroxychalcones was developed to afford a wide range of 4-indole substituted chromans bearing a ketal motif in 77–99% yields.
Stapled peptides as a new technology to investigate protein–protein interactions in human platelets
Authors: Iegre Jessica , Ahmed Niaz S. , Gaynord Josephine S. , Wu Yuteng , Herlihy Kara M. , Tan Yaw Sing , Lopes-Pires Maria E. , Jha Rupam , Lau Yu Heng , Sore Hannah F. , Verma Chandra , O' Donovan Daniel H. , Pugh Nicholas , Spring David R.
Published: April 2018

We describe the first application of stapled peptides in human platelets. Bim BH3 stapled peptides are used to overcome the limitations of traditional methods and uncover a new role for Bim in platelet activation.
Sustainable luminescent solar concentrators based on organic–inorganic hybrids modified with chlorophyll
Authors: Frias A. R. , Pecoraro E. , Correia S. F. H. , Minas L. M. G. , Bastos A. R. , García-Revilla S. , Balda R. , Ribeiro S. J. L. , André P. S. , Carlos L. D. , Ferreira R. A. S.
Published: April 2018

Development of natural-based luminescent solar concentrators able to convert sunlight into specific wavelengths which are guided by total internal reflection to a PV device featuring reliable, sustainable and competitive energy systems.
A stable electron-deficient metal–organic framework for colorimetric and luminescence sensing of phenols and anilines
Authors: Gong Teng , Li Peng , Sui Qi , Chen Jinquan , Xu Jianhua , Gao En-Qing
Published: April 2018

A Eu3+ MOF with ideally spaced electron-deficient viologen moieties is capable of highly sensitive colorimetric/luminescence detection of electron-rich aromatic contaminants in water through charge transfer and resonance energy transfer.
Fabrication of an electroconductive, flexible, and soft poly(3,4-ethylenedioxythiophene)–thermoplastic polyurethane hybrid scaffold by in situ vapor phase polymerization
Authors: Park Jin Seul , Kim Boram , Lee Byong-Taek , Choi Jong Seob , Yim Jin-Heong
Published: April 2018

We fabricated an electroconductive, flexible, and soft poly(3,4-ethylenedioxythiophene)–thermoplastic polyurethane hybrid scaffold by in situ vapor phase polymerization.
Intracellular delivery of a native functional protein using cell-penetrating peptide functionalized cubic MSNs with ultra-large mesopores
Authors: Bae Sang-Eun , Lyu Soo Kyung , Kim Ki-Jung , Shin Hee Joo , Kwon Hyockman , Huh Seong
Published: April 2018

Pore-enlarged 3D cubic cMSNs were successfully prepared, and their surfaces were functionalized by a cell-penetrating R8-peptide through the click reaction for cytosolic delivery of a functional protein in its native form.
Approaches to improve the biocompatibility and systemic circulation of inorganic porous nanoparticles
Authors: Tamarov K. , Näkki S. , Xu W. , Lehto V.-P.
Published: April 2018

The exploitation of various inorganic nanoparticles as drug carriers and therapeutics is becoming increasingly common.
Red-emission over a wide range of wavelengths at various temperatures from tetragonal BaCN2:Eu2+
Authors: Masubuchi Yuji , Nishitani Sayaka , Hosono Akira , Kitagawa Yuuki , Ueda Jumpei , Tanabe Setsuhisa , Yamane Hisanori , Higuchi Mikio , Kikkawa Shinichi
Published: April 2018

A new tetragonal BaCN2 polymorph was obtained via a simple nitridation reaction of BaCO2, and the Eu doped product showed a red emission with an extremely wide range of red-shift of the emission wavelength with decreasing temperature.
Half-metallicity and enhanced ferromagnetism in Li-adsorbed ultrathin chromium triiodide
Authors: Guo Yilv , Yuan Shijun , Wang Bing , Shi Li , Wang Jinlan
Published: April 2018

Ultrathin CrI3 nanosheets can be tuned to be half-metallic and the intrinsic ferromagnetism can be largely enhanced by the adsorption of Li atoms.
Fast concrete crack detection method via L2 sparse representation
Authors: Wang Baoxian , Zhang Quanle , Zhao Weigang
Published: April 2018

A fast concrete crack detector based on L2 sparse representation is proposed. Specifically, via dividing the existing concrete images, many representative crack and non‐crack image regions are selected for the over‐complete dictionary. To suppress the noise disturbances, discrete cosine transformation is to extract the frequency‐domain characteristics of these regions. For one new concrete image, it is first divided into many non‐overlapping regions, and their sparse coefficients are fast computed on the established over‐complete dictionary. Moreover then, a pooling operation is to extract the difference value between their sum coefficients on the crack templates and those on the non‐crack ones, and easily yet effectively select the crack candidates via the sign bit of their difference values. Experiments on the practical concrete images show that the algorithm has high precision and efficiency.
Fast group detection for massive MIMOs
Authors: Lu Hoang‐Yang , Yen Mao‐Hsu , Chen Bo‐Sing
Published: April 2018

In this study, the authors consider symbol detection at the receiver of the base station for uplink massive multiple‐input multiple‐output (MIMO) systems over a fading channel, in which the base station uses a large number of antennas to serve many users. First, the authors review the existing detection methods such as the minimum mean square error and Vertical‐Bell Laboratories Layered Space Time (V‐BLAST). In addition, because the bit error rate (BER) performance of V‐BLAST is close to that of the optimal method, the authors describe the procedures of the V‐BLAST in detail. Then, to achieve a satisfactory trade‐off between the BER performance and the computational complexity for practical implementation in massive MIMO systems, the authors propose a fast group‐based symbol detection scheme. They also derive the expressions needed to select the symbol indices of a group for detection. Our simulation results and complexity analysis show that the performance of the proposed scheme is close to that of the V‐BLAST algorithm with a significant saving in computational complexity.
Uplink training with pilot optimisation for multicell massive multiple‐input multiple‐output systems
Authors: Nguyen Hieu V. , Nguyen Van‐Dinh , Nguyen Hien M. , Shin Oh‐Soon
Published: April 2018

The authors investigate pilot contamination in a multicell massive multiple‐input multiple‐output system, in which the estimated channel state information (CSI) is significantly different from the real CSI. Pilot contamination is an obstacle to achievable rates for users. The authors first propose an uplink training strategy to limit the effect of intercell pilot contamination on channel estimation with low complexity. As a result, the downlink data rate through the reciprocal channels is significantly improved. However, as the conventional uplink training, this strategy suffers from intra‐cell pilot contamination when the length of pilots is smaller than the number of users in a cell, while increasing the length of pilots degrades the spectral efficiency. The authors, therefore, propose a pilot optimisation that can be incorporated into the proposed training strategy. Based on the minimum mean square error criterion, they derive a closed‐form equation to determine the optimal pilots for all users in a multicell system. The joint pilot optimisation and proposed uplink training strategy is found to outperform other schemes, especially when the number of users exceeds the length of pilots in a cell. Numerical results verify that the downlink achievable rate with the proposed training strategy and pilot optimisation outperforms that with conventional approaches.
Energy efficient millimetre‐wave fronthaul and OFDMA resource optimisation in C‐RANs
Authors: Jing Zewei , Qin Meng , Yang Qinghai , Kwak Kyung‐Sup , Rao Ramesh R.
Published: April 2018

Recently, millimetre‐wave (mmWave) wireless fronthauls have been regarded as an effective solution to deploy remote radio heads with higher flexibility and efficiency in cloud radio access networks (C‐RANs). Different from the traditional fibre fronthauls, in order to maximise the utilisation of the time‐frequency resource, the mmWave wireless fronthauls are more expected to operate in a dynamic allocation manner. In this study, the energy efficient mmWave fronthaul and OFDMA resource optimisation in C‐RANs is investigated. The TDMA‐based fronthaul allocation mechanism is first presented and then the joint resource optimisation is formulated as an energy efficiency (EE) maximisation problem which is in the form of a mixed‐integer non‐linear fractional programming (MINLFP) problem. By taking advantage of the Dinkelbach method, the MINLFP problem is transformed into a subtractive optimisation problem and solved by using the Lagrange dual decomposition theory. Moreover, a maximal weighted bipartite graph matching approach is proposed to determine the optimal resource block allocation. Finally, extensive simulation results are provided to evaluate the EE performance of the proposed algorithm by comparing with several benchmark schemes, and it shows that the proposed algorithm can achieve great EE performance gain over the benchmark schemes.
Comparative effects of capacitive and inductive superstrates on the RCA's gain
Authors: Zhou Lin , Chen Xing , Cui Yuguo , Duan Xin
Published: April 2018

The radiation performance of the resonant cavity antenna (RCA) is mainly determined by the superstrate, and thereby various superstrates are designed for the RCA to obtain high performance. In this work, the comparative effects of the capacitive and inductive superstrates on the RCA's gain are investigated systematically. Three approaches including the leaky‐wave model, full‐wave simulations and prototype measurements are employed for the investigation. Using the leaky‐wave model, the gains of the RCA with various superstrates are calculated and a difference between the gains with the capacitive and inductive superstrates is observed. Full‐wave simulations and prototype measurements further prove the result. All the approaches demonstrate that the capacitive superstrate has the potential to obtain a higher gain, in comparison with the inductive superstrate having the same reflection magnitude and aperture size.
Design and analysis of wideband low‐power LNA for improved RF performance with compact chip area
Authors: Pandey Sunil , Gawande Tushar , Inge Shashank , Pathak Abhijeet , Kondekar Pravin N.
Published: April 2018

Here, a wideband low‐noise amplifier (LNA) based on the two‐stage cascade configuration is presented to improve the radiofrequency (RF) performance. With the common gate (CG) input stage, the proposed LNA provides wideband input matching, while the wideband gain response was achieved using the peaking inductors inserted at the drain terminals of each stage. With a standard CMOS process, the chip area of the proposed wideband LNA is only 0.116 mm2. However, it consumes a 5.4 mW power from a supply voltage of . From the post‐layout simulation results, it achieves maximum power gain of 11.13 dB at 8.5 GHz, input return loss below −9.44 dB, reverse isolation less than −60 dB, and small group delay variation of ±97 ps across 8.5–20 GHz frequency range. Moreover, noise figure (NF) lies in the range of 2.19–3.23 dB, whereas the NF minimum () varies in the range of 1.55–2.91 dB for 8.5–20 GHz frequency range. Apart from this, the proposed LNA achieves an IIP3 of 0.96 dBm, when a two‐tone test is performed with a frequency spacing of 50 MHz.
Review of planning methodologies used for determination of optimal generation capacity mix: the cases of high shares of PV and wind
Authors: Senatla Mamahloko , Bansal Ramesh C.
Published: April 2018

It is an undeniable fact that energy systems all over the world are at the point of a paradigm shift as a need for decarbonisation is eminent and unavoidable. The pressure to decarbonise mounts year after year. Since two thirds of all anthropogenic greenhouse‐gas emissions come from the energy sector, decarbonisation is more about reducing emissions in the energy system than any other system in the world. The increased need for decarbonisation has resulted in the increased installation of photovoltaic (PV) and wind systems in countries such as China, India, Germany, Ireland, Denmark, Japan and USA. The increased use of intermittent renewable energy resources introduces a need for advanced methods of planning because traditional planning methods give sub‐optimal generation capacity mix when the electric grid is faced with high shares of variable renewable energy resources such as PV and wind. In light of this, this review highlights the major changes in planning methodologies when solving for optimal penetration of generation capacity in systems with high shares of PV and wind. The major highlights are placed on why the methodologies need to evolve as penetration levels of PV and wind increase and further highlight missing issues from the current advanced methods.
Autonomous grid‐synchronising control of VSC‐HVDC with real‐time frequency mirroring capability for wind farm integration
Authors: Yang Renxin , Zhang Chen , Cai Xu , Shi Gang
Published: April 2018

This study provides a novel control method for voltage source converter high‐voltage direct current (VSC‐HVDC) systems with two salient features: autonomous grid‐synchronisation without phase‐locked loop and real‐time grid frequency mirroring capability. The first feature is realised using a newly proposed control method for receiving end converter (REC) called inertial synchronising control (ISC). This method innovatively adopts the physical inertia of DC capacitors to directly synchronise with the grid, without emulating the motional equation of a synchronous generator (SG) as virtual SG control. Hence, less control loops and easy parameter tuning are achieved. The control robustness to grid impedance variation is also improved. Moreover, the second feature is realised with the merit of ISC. Owing to the fast grid‐synchronisation capability of ISC, grid frequency dynamic is bound with DC voltage dynamic intrinsically; hence, the instantaneous grid frequency information can be obtained by measuring the local DC voltage of sending end converter, whereby wind turbines can proceed with inertial and frequency response. Consequently, REC is similar to SG in terms of electromechanical characteristics. The effectiveness of the proposed method is evaluated by comparing it to an existing method in PSCAD/EMTDC, and its performance on the robustness to grid impedance variation is addressed.
Radial basis function network‐based available measurement classification of interferometric radar altimeter for terrain‐aided navigation
Authors: Lee Jungshin , Bang Hyochoong
Published: April 2018

The purpose of this study is to propose a measurement classification method necessary to implement precision terrain‐aided navigation (TAN) by using an interferometric radar altimeter (IRA) as a technology that can replace global positioning system/inertial navigation system integrated navigation. IRA is a sensor that extracts the angle perpendicular to the direction of flight, the look angle, and the slant range from the aircraft to the nearest terrain point. Unlike the radio altimeter which only measures the direct downward distance, IRA can be converted into three‐dimensional coordinates in the navigation system. However, the IRA output has a disadvantage that it has uncertainty that cannot be predicted due to the signal processing and environmental factors. Therefore, a useful navigation technique for classifying sensor outputs is needed to implement precision TAN. This study introduces the radial basis function network and extreme learning machine methods to classify available IRA measurements and verifies the suitability of the proposed classification method by applying it to the bank of Kalman filter) and particle filter‐based TAN.
Effective improvement in the etching characteristics of Si{110} in low concentration TMAH solution
Authors: Swarnalatha Veerla , Narasimha Rao Avvaru Venkata , Pal Prem
Published: April 2018

An aqueous tetramethylammonium hydroxide (TMAH) solution is widely used for silicon wet anisotropic etching to perform bulk micromachining for the fabrication of microstructures on a silicon wafer. To reduce the etching time to increase the productivity, etchant must provide high etch rate. In the present work, the etching characteristics of Si{110} in low concentration TMAH (5 wt%) with the addition of various concentrations (5–20%) of reducing agent hydroxylamine (NH2 OH) have been studied to increase the etch rate of Si{110} to reduce the etch time for the fabrication of microstructures. Moreover, it is aimed to enhance the undercutting at convex corner for the fast release of the structure. The etch rate of Si{110} and the undercutting at convex corners with the addition of NH2 OH increases by more than three times that in pure TMAH. In addition to the etch rate and undercutting, the effect of NH2 OH on etched surface morphology is investigated systematically. The present study is focused to enhance the application of wet etching in silicon micromachining for the fabrication of various kinds of microstructures for applications in microelectromechanical systems.
Comparison of the power-2 limb-darkening law from the STAGGER-grid to Kepler light curves of transiting exoplanets
Authors: Maxted P. F. L.
Published: April 2018

Context. Inaccurate limb-darkening models can be a significant source of error in the analysis of the light curves for transiting exoplanet and eclipsing binary star systems, particularly for high-precision light curves at optical wavelengths. The power-2 limb-darkening law, Iλ(µ) = 1 − c(1−µα), has recently been proposed as a good compromise between complexity and precision in the treatment of limb-darkening.

Aims. My aim is to develop a practical implementation of the power-2 limb-darkening law and to quantify the accuracy of this implementation.

Methods. I have used synthetic spectra based on the 3D stellar atmosphere models from the STAGGER-grid to compute the limb-darkening for several passbands (UBVRI, CHEOPS, TESS, Kepler, etc.). The parameters of the power-2 limb-darkening laws are optimized using a least-squares fit to a simulated light curve computed directly from the tabulated Iλ(μ) values. I use the transformed parameters h1 = 1 − c(1 − 2−α) and h2 = c2−α to directly compare these optimized limb-darkening parameters to the limb darkening measured from Kepler light curves of 16 transiting exoplanet systems.

Results. The posterior probability distributions (PPDs) of the transformed parameters h1 and h2 resulting from the light curve analysis are found to be much less strongly correlated than the PPDs for c and α. The agreement between the computed and observed values of (h1, h2) is generally very good but there are significant differences between the observed and computed values for Kepler-17, the only star in the sample that shows significant variability between the eclipses due to magnetic activity (star spots).

Conclusions. The tabulation of h1 and h2 provided here can be used to accurately model the light curves of transiting exoplanets. I also provide estimates of the priors that should be applied to transformed parameters h1 and h2 based on my analysis of the Kepler light curves of 16 stars with transiting exoplanets.