bluuebunny/crossref_metadata_2025 huggingface dataset:
Ciliate Paramecium is a natural reservoir of Legionella pneumophila
Authors: Watanabe Kenta , Nakao Ryo , Fujishima Masahiro , Tachibana Masato , Shimizu Takashi , Watarai Masahisa
Published: April 2016

Legionella pneumophila, the causative agent of Legionnaires’ disease, replicates within alveolar macrophages and free-living amoebae. However, the lifestyle of L. pneumophila in the environment remains largely unknown. Here we established a novel natural host model of L. pneumophila endosymbiosis using the ciliate Paramecium caudatum. We also identified Legionella endosymbiosis-modulating factor A (LefA), which contributes to the change in life stage from endosymbiosis to host lysis, enabling escape to the environment. We isolated L. pneumophila strains from the environment and they exhibited cytotoxicity toward P. caudatum and induced host lysis. Acidification of the Legionella-containing vacuole (LCV) was inhibited and enlarged LCVs including numerous bacteria were observed in P. caudatum infected with L. pneumophila. An isogenic L. pneumophila lefA mutant exhibited decreased cytotoxicity toward P. caudatum and impaired the modification of LCVs, resulting in the establishment of endosymbiosis between them. Our results suggest that L. pneumophila may have a mechanism to switch their endosymbiosis in protistan hosts in the environment.
PFKFB3 Control of Cancer Growth by Responding to Circadian Clock Outputs
Authors: Chen Lili , Zhao Jiajia , Tang Qingming , Li Honggui , Zhang Chenguang , Yu Ran , Zhao Yan , Huo Yuqing , Wu Chaodong
Published: April 2016

Circadian clock dysregulation promotes cancer growth. Here we show that PFKFB3, the gene that encodes for inducible 6-phosphofructo-2-kinase as an essential supporting enzyme of cancer cell survival through stimulating glycolysis, mediates circadian control of carcinogenesis. In patients with tongue cancers, PFKFB3 expression in both cancers and its surrounding tissues was increased significantly compared with that in the control and was accompanied with dys-regulated expression of core circadian genes. In the in vitro systems, SCC9 tongue cancer cells displayed rhythmic expression of PFKFB3 and CLOCK that was distinct from control KC cells. Furthermore, PFKFB3 expression in SCC9 cells was stimulated by CLOCK through binding and enhancing the transcription activity of PFKFB3 promoter. Inhibition of PFKFB3 at zeitgeber time 7 (ZT7), but not at ZT19 caused significant decreases in lactate production and in cell proliferation. Consistently, PFKFB3 inhibition in mice at circadian time (CT) 7, but not CT19 significantly reduced the growth of implanted neoplasms. Taken together, these findings demonstrate PFKFB3 as a mediator of circadian control of cancer growth, thereby highlighting the importance of time-based PFKFB3 inhibition in cancer treatment.
CRISPR-Cas9D10A nickase-based genotypic and phenotypic screening to enhance genome editing
Authors: Chiang Ting-Wei Will , le Sage Carlos , Larrieu Delphine , Demir Mukerrem , Jackson Stephen P.
Published: April 2016

The RNA-guided Cas9 nuclease is being widely employed to engineer the genomes of various cells and organisms. Despite the efficient mutagenesis induced by Cas9, off-target effects have raised concerns over the system’s specificity. Recently a “double-nicking” strategy using catalytic mutant Cas9D10A nickase has been developed to minimise off-target effects. Here, we describe a Cas9D10A-based screening approach that combines an All-in-One Cas9D10A nickase vector with fluorescence-activated cell sorting enrichment followed by high-throughput genotypic and phenotypic clonal screening strategies to generate isogenic knockouts and knock-ins highly efficiently, with minimal off-target effects. We validated this approach by targeting genes for the DNA-damage response (DDR) proteins MDC1, 53BP1, RIF1 and P53, plus the nuclear architecture proteins Lamin A/C, in three different human cell lines. We also efficiently obtained biallelic knock-in clones, using single-stranded oligodeoxynucleotides as homologous templates, for insertion of an EcoRI recognition site at the RIF1 locus and introduction of a point mutation at the histone H2AFX locus to abolish assembly of DDR factors at sites of DNA double-strand breaks. This versatile screening approach should facilitate research aimed at defining gene functions, modelling of cancers and other diseases underpinned by genetic factors and exploring new therapeutic opportunities.
Lysine fatty acylation promotes lysosomal targeting of TNF-α
Authors: Jiang Hong , Zhang Xiaoyu , Lin Hening
Published: April 2016

Tumor necrosis factor-α (TNF-α) is a proinflammation cytokine secreted by various cells. Understanding its secretive pathway is important to understand the biological functions of TNF-α and diseases associated with TNF-α. TNF-α is one of the first proteins known be modified by lysine fatty acylation (e.g. myristoylation). We previously demonstrated that SIRT6, a member of the mammalian sirtuin family of enzymes, can remove the fatty acyl modification on TNF-α and promote its secretion. However, the mechanistic details about how lysine fatty acylation regulates TNF-α secretion have been unknown. Here we present experimental data supporting that lysine fatty acylation promotes lysosomal targeting of TNF-α. The result is an important first step toward understanding the biological functions of lysine fatty acylation.
A multiple-shape memory polymer-metal composite actuator capable of programmable control, creating complex 3D motion of bending, twisting, and oscillation
Authors: Shen Qi , Trabia Sarah , Stalbaum Tyler , Palmre Viljar , Kim Kwang , Oh Il-Kwon
Published: April 2016

Development of biomimetic actuators has been an essential motivation in the study of smart materials. However, few materials are capable of controlling complex twisting and bending deformations simultaneously or separately using a dynamic control system. Here, we report an ionic polymer-metal composite actuator having multiple-shape memory effect, and is able to perform complex motion by two external inputs, electrical and thermal. Prior to the development of this type of actuator, this capability only could be realized with existing actuator technologies by using multiple actuators or another robotic system. This paper introduces a soft multiple-shape-memory polymer-metal composite (MSMPMC) actuator having multiple degrees-of-freedom that demonstrates high maneuverability when controlled by two external inputs, electrical and thermal. These multiple inputs allow for complex motions that are routine in nature, but that would be otherwise difficult to obtain with a single actuator. To the best of the authors’ knowledge, this MSMPMC actuator is the first solitary actuator capable of multiple-input control and the resulting deformability and maneuverability.
Catechol degradation on hematite/silica–gas interface as affected by gas composition and the formation of environmentally persistent free radicals
Authors: Li Hao , Guo Huiying , Pan Bo , Liao Shaohua , Zhang Di , Yang Xikun , Min Chungang , Xing Baoshan
Published: April 2016

Environmentally persistent free radicals (EPFRs) formed on a solid particle surface have received increasing attention because of their toxic effects. However, organic chemical fate regulated by EPFRs has rarely been investigated, and this information may provide the missing link in understanding their environmental behavior. Previous studies have suggested that the reduction of transition metals is involved in EPFRs formation. We thus hypothesize that an oxidative environment may inhibit EPFRs formation in particle-gas interface, which will consequently release free radicals and accelerate organic chemical degradation. Our result indicates that a 1% hematite coating on a silica surface inhibited catechol degradation in N2, especially at low catechol loadings on solid particles (SCT). However, under an O2 environment, catechol degradation decreased when SCT was <1 μg/mg but increased when SCT was >1 μg/mg. Stable organic free radicals were observed in the N2 system with g factors in the 2.0035–2.0050 range, suggesting the dominance of oxygen-centered free radicals. The introduction of O2 into the catechol degradation system substantially decreased the free radical signals and decreased the Fe(II) content. These results were observed in both dark and light irradiation systems, indicating the ubiquitous presence of EPFRs in regulating the fate of organic chemicals.
The dynamics of carbon stored in xylem sapwood to drought-induced hydraulic stress in mature trees
Authors: Yoshimura Kenichi , Saiki Shin-Taro , Yazaki Kenichi , Ogasa Mayumi Y. , Shirai Makoto , Nakano Takashi , Yoshimura Jin , Ishida Atsushi
Published: April 2016

Climate-induced forest die-off is widespread in multiple biomes, strongly affecting the species composition, function and primary production in forest ecosystems. Hydraulic failure and carbon starvation in xylem sapwood are major hypotheses to explain drought-induced tree mortality. Because it is difficult to obtain enough field observations on drought-induced mortality in adult trees, the current understanding of the physiological mechanisms for tree die-offs is still controversial. However, the simultaneous examination of water and carbon uses throughout dehydration and rehydration processes in adult trees will contribute to clarify the roles of hydraulic failure and carbon starvation in tree wilting. Here we show the processes of the percent loss of hydraulic conductivity (PLC) and the content of nonstructural carbohydrates (NSCs) of distal branches in woody plants with contrasting water use strategy. Starch was converted to soluble sugar during PLC progression under drought, and the hydraulic conductivity recovered following water supply. The conversion of NSCs is strongly associated with PLC variations during dehydration and rehydration processes, indicating that stored carbon contributes to tree survival under drought; further carbon starvation can advance hydraulic failure. We predict that even slow-progressing drought degrades forest ecosystems via carbon starvation, causing more frequent catastrophic forest die-offs than the present projection.
Broadband absorption enhancement in plasmonic nanoshells-based ultrathin microcrystalline-Si solar cells
Authors: Raja Waseem , Bozzola Angelo , Zilio Pierfrancesco , Miele Ermanno , Panaro Simone , Wang Hai , Toma Andrea , Alabastri Alessandro , De Angelis Francesco , Zaccaria Remo Proietti
Published: April 2016

With the objective to conceive a plasmonic solar cell with enhanced photocurrent, we investigate the role of plasmonic nanoshells, embedded within a ultrathin microcrystalline silicon solar cell, in enhancing broadband light trapping capability of the cell and, at the same time, to reduce the parasitic loss. The thickness of the considered microcrystalline silicon (μc-Si) layer is only ~1/6 of conventional μc-Si based solar cells while the plasmonic nanoshells are formed by a combination of silica and gold, respectively core and shell. We analyze the cell optical response by varying both the geometrical and optical parameters of the overall device. In particular, the nanoshells core radius and metal thickness, the periodicity, the incident angle of the solar radiation and its wavelength are varied in the widest meaningful ranges. We further explain the reason for the absorption enhancement by calculating the electric field distribution associated to resonances of the device. We argue that both Fabry-Pérot-like and localized plasmon modes play an important role in this regard.
Insulin resistance is associated with altered amino acid metabolism and adipose tissue dysfunction in normoglycemic women
Authors: Wiklund Petri , Zhang Xiaobo , Pekkala Satu , Autio Reija , Kong Lingjia , Yang Yifan , Keinänen-Kiukaanniemi Sirkka , Alen Markku , Cheng Sulin
Published: April 2016

Insulin resistance is associated adiposity, but the mechanisms are not fully understood. In this study, we aimed to identify early metabolic alterations associated with insulin resistance in normoglycemic women with varying degree of adiposity. One-hundred and ten young and middle-aged women were divided into low and high IR groups based on their median HOMA-IR (0.9 ± 0.4 vs. 2.8 ± 1.2). Body composition was assessed using DXA, skeletal muscle and liver fat by proton magnetic resonance spectroscopy, serum metabolites by nuclear magnetic resonance spectroscopy and adipose tissue and skeletal muscle gene expression by microarrays. High HOMA-IR subjects had higher serum branched-chain amino acid concentrations (BCAA) (p < 0.05 for both). Gene expression analysis of subcutaneous adipose tissue revealed significant down-regulation of genes related to BCAA catabolism and mitochondrial energy metabolism and up-regulation of several inflammation-related pathways in high HOMA-IR subjects (p < 0.05 for all), but no differentially expressed genes in skeletal muscle were found. In conclusion, in normoglycemic women insulin resistance was associated with increased serum BCAA concentrations, down-regulation of mitochondrial energy metabolism and increased expression of inflammation-related genes in the adipose tissue.
Sphingosine 1-phosphate receptor 2 (S1P2) attenuates reactive oxygen species formation and inhibits cell death: implications for otoprotective therapy
Authors: Herr Deron R. , Reolo Marie J. Y. , Peh Yee Xin , Wang Wei , Lee Chang-Wook , Rivera Rich , Paterson Ian C. , Chun Jerold
Published: April 2016

Ototoxic drugs, such as platinum-based chemotherapeutics, often lead to permanent hearing loss through apoptosis of neuroepithelial hair cells and afferent neurons of the cochlea. There is no approved therapy for preventing or reversing this process. Our previous studies identified a G protein-coupled receptor (GPCR), S1P2, as a potential mediator of otoprotection. We therefore sought to identify a pharmacological approach to prevent cochlear degeneration via activation of S1P2. The cochleae of S1pr2−/− knockout mice were evaluated for accumulation of reactive oxygen species (ROS) with a nitro blue tetrazolium (NBT) assay. This showed that loss of S1P2 results in accumulation of ROS that precedes progressive cochlear degeneration as previously reported. These findings were supported by in vitro cell-based assays to evaluate cell viability, induction of apoptosis and accumulation of ROS following activation of S1P2 in the presence of cisplatin. We show for the first time, that activation of S1P2 with a selective receptor agonist increases cell viability and reduces cisplatin-mediated cell death by reducing ROS. Cumulatively, these results suggest that S1P2 may serve as a therapeutic target for attenuating cisplatin-mediated ototoxicity.
MiR-299-5p regulates apoptosis through autophagy in neurons and ameliorates cognitive capacity in APPswe/PS1dE9 mice
Authors: Zhang Yueqi , Liu Chengeng , Wang Jinling , Li Qiliang , Ping Hong , Gao Shichao , Wang Peichang
Published: April 2016

Abnormalities of autophagy can result in neurodegenerative disorders such as Alzheimer’s disease (AD). Nevertheless, the regulatory mechanisms of autophagy in AD are not well understood. Here, we describe our findings that microRNA (miR)-299-5p functions as an autophagy inhibitor by suppressing Atg5 and antagonizing caspase-dependent apoptosis. We observed decreased levels of miR-299-5p both in primary neurons under conditions of starvation and in hippocampi of APPswe/PS1dE9 mice. Additionally, low levels of miR-299-5p were observed in cerebrospinal fluid of AD patients. MiR-299-5p treatment resulted in attenuation of Atg5 and autophagy in primary neurons from APPswe/PS1dE9 mice, N2a cells and SH-SY5Y cells, whereas antagomiR-299-5p enhanced autophagy. Atg5 was verified as a direct target of miR-299-5p by dual luciferase reporter assays. Furthermore, transfection of miR-299-5p into primary hippocampal neurons caused the attenuation of caspase-mediated apoptosis, which was reversed upon starvation-induced autophagy. Inhibition of autophagy by shRNA knockdown of LC3β reduced apoptotic neuron death induced by antagomiR-299-5p. Injection of agomiR-299-5p into the cerebral ventricles of AD mice inhibited both autophagy and apoptosis and also improved the cognitive performance of mice. Overall, our results suggest that miR-299-5p modulates neuron survival programs by regulating autophagy. Thus, miR-299-5p serves as a potential neuroprotective factor in AD.
SPECT-OPT multimodal imaging enables accurate evaluation of radiotracers for β-cell mass assessments
Authors: Eter Wael A. , Parween Saba , Joosten Lieke , Frielink Cathelijne , Eriksson Maria , Brom Maarten , Ahlgren Ulf , Gotthardt Martin
Published: April 2016

Single Photon Emission Computed Tomography (SPECT) has become a promising experimental approach to monitor changes in β-cell mass (BCM) during diabetes progression. SPECT imaging of pancreatic islets is most commonly cross-validated by stereological analysis of histological pancreatic sections after insulin staining. Typically, stereological methods do not accurately determine the total β-cell volume, which is inconvenient when correlating total pancreatic tracer uptake with BCM. Alternative methods are therefore warranted to cross-validate β-cell imaging using radiotracers. In this study, we introduce multimodal SPECT - optical projection tomography (OPT) imaging as an accurate approach to cross-validate radionuclide-based imaging of β-cells. Uptake of a promising radiotracer for β-cell imaging by SPECT, 111In-exendin-3, was measured by ex vivo-SPECT and cross evaluated by 3D quantitative OPT imaging as well as with histology within healthy and alloxan-treated Brown Norway rat pancreata. SPECT signal was in excellent linear correlation with OPT data as compared to histology. While histological determination of islet spatial distribution was challenging, SPECT and OPT revealed similar distribution patterns of 111In-exendin-3 and insulin positive β-cell volumes between different pancreatic lobes, both visually and quantitatively. We propose ex vivo SPECT-OPT multimodal imaging as a highly accurate strategy for validating the performance of β-cell radiotracers.
Unique fractal evaluation and therapeutic implications of mitochondrial morphology in malignant mesothelioma
Authors: Lennon Frances E. , Cianci Gianguido C. , Kanteti Rajani , Riehm Jacob J. , Arif Qudsia , Poroyko Valeriy A. , Lupovitch Eitan , Vigneswaran Wickii , Husain Aliya , Chen Phetcharat , Liao James K. , Sattler Martin , Kindler Hedy L. , Salgia Ravi
Published: April 2016

Malignant mesothelioma (MM), is an intractable disease with limited therapeutic options and grim survival rates. Altered metabolic and mitochondrial functions are hallmarks of MM and most other cancers. Mitochondria exist as a dynamic network, playing a central role in cellular metabolism. MM cell lines display a spectrum of altered mitochondrial morphologies and function compared to control mesothelial cells. Fractal dimension and lacunarity measurements are a sensitive and objective method to quantify mitochondrial morphology and most importantly are a promising predictor of response to mitochondrial inhibition. Control cells have high fractal dimension and low lacunarity and are relatively insensitive to mitochondrial inhibition. MM cells exhibit a spectrum of sensitivities to mitochondrial inhibitors. Low mitochondrial fractal dimension and high lacunarity correlates with increased sensitivity to the mitochondrial inhibitor metformin. Lacunarity also correlates with sensitivity to Mdivi-1, a mitochondrial fission inhibitor. MM and control cells have similar sensitivities to cisplatin, a chemotherapeutic agent used in the treatment of MM. Neither oxidative phosphorylation nor glycolytic activity, correlated with sensitivity to either metformin or mdivi-1. Our results suggest that mitochondrial inhibition may be an effective and selective therapeutic strategy in mesothelioma, and identifies mitochondrial morphology as a possible predictor of response to targeted mitochondrial inhibition.
Synergistic Modification Induced Specific Recognition between Histone and TRIM24 via Fluctuation Correlation Network Analysis
Authors: Zhang Jinmai , Luo Huajie , Liu Hao , Ye Wei , Luo Ray , Chen Hai-Feng
Published: April 2016

Histone modification plays a key role in gene regulation and gene expression. TRIM24 as a histone reader can recognize histone modification. However the specific recognition mechanism between TRIM24 and histone modification is unsolved. Here, systems biology method of dynamics correlation network based on molecular dynamics simulation was used to answer the question. Our network analysis shows that the dynamics correlation network of H3K23ac is distinctly different from that of wild type and other modifications. A hypothesis of “synergistic modification induced recognition” is then proposed to link histone modification and TRIM24 binding. These observations were further confirmed from community analysis of networks with mutation and network perturbation. Finally, a possible recognition pathway is also identified based on the shortest path search for H3K23ac. Significant difference of recognition pathway was found among different systems due to methylation and acetylation modifications. The analysis presented here and other studies show that the dynamic network-based analysis might be a useful general strategy to study the biology of protein post-translational modification and associated recognition.
Structural insights into the Escherichia coli lysine decarboxylases and molecular determinants of interaction with the AAA+ ATPase RavA
Authors: Kandiah Eaazhisai , Carriel Diego , Perard Julien , Malet Hélène , Bacia Maria , Liu Kaiyin , Chan Sze W. S. , Houry Walid A. , Ollagnier de Choudens Sandrine , Elsen Sylvie , Gutsche Irina
Published: April 2016

The inducible lysine decarboxylase LdcI is an important enterobacterial acid stress response enzyme whereas LdcC is its close paralogue thought to play mainly a metabolic role. A unique macromolecular cage formed by two decamers of the Escherichia coli LdcI and five hexamers of the AAA+ ATPase RavA was shown to counteract acid stress under starvation. Previously, we proposed a pseudoatomic model of the LdcI-RavA cage based on its cryo-electron microscopy map and crystal structures of an inactive LdcI decamer and a RavA monomer. We now present cryo-electron microscopy 3D reconstructions of the E. coli LdcI and LdcC, and an improved map of the LdcI bound to the LARA domain of RavA, at pH optimal for their enzymatic activity. Comparison with each other and with available structures uncovers differences between LdcI and LdcC explaining why only the acid stress response enzyme is capable of binding RavA. We identify interdomain movements associated with the pH-dependent enzyme activation and with the RavA binding. Multiple sequence alignment coupled to a phylogenetic analysis reveals that certain enterobacteria exert evolutionary pressure on the lysine decarboxylase towards the cage-like assembly with RavA, implying that this complex may have an important function under particular stress conditions.
Sight restoration after congenital blindness does not reinstate alpha oscillatory activity in humans
Authors: Bottari Davide , Troje Nikolaus F. , Ley Pia , Hense Marlene , Kekunnaya Ramesh , Röder Brigitte
Published: April 2016

Functional brain development is characterized by sensitive periods during which experience must be available to allow for the full development of neural circuits and associated behavior. Yet, only few neural markers of sensitive period plasticity in humans are known. Here we employed electroencephalographic recordings in a unique sample of twelve humans who had been blind from birth and regained sight through cataract surgery between four months and 16 years of age. Two additional control groups were tested: a group of visually impaired individuals without a history of total congenital blindness and a group of typically sighted individuals. The EEG was recorded while participants performed a visual discrimination task involving intact and scrambled biological motion stimuli. Posterior alpha and theta oscillations were evaluated. The three groups showed indistinguishable behavioral performance and in all groups evoked theta activity varied with biological motion processing. By contrast, alpha oscillatory activity was significantly reduced only in individuals with a history of congenital cataracts. These data document on the one hand brain mechanisms of functional recovery (related to theta oscillations) and on the other hand, for the first time, a sensitive period for the development of alpha oscillatory activity in humans.
Theoretical studies on CO2 capture behavior of quaternary ammonium-based polymeric ionic liquids
Authors: Wang Tao , Ge Kun , Chen Kexian , Hou Chenglong , Fang Mengxiang
Published: April 2016

How does a humidity swing adsorption process work? Theoretical studies are conducted to reveal the underlying mechanisms, especially the proton transfer process of hydrated water.
Octahedron-based gallium borates (Ga-PKU-1) with an open framework: acidity, catalytic dehydration and structure–activity relationship
Authors: Wang Guangjia , Wang Weilu , Zhang Fenhua , Gao Wenliang , Cong Rihong , Yang Tao
Published: April 2016

The octahedron-based Ga-PKU-1 catalyst with an open framework acted as an efficient solid acid catalyst for isopropanol decomposition.
Synergistic photothermal antimicrobial therapy using graphene oxide/polymer composite layer-by-layer thin films
Authors: Kurapati Rajendra , Vaidyanathan Mahalakshmi , Raichur Ashok M.
Published: April 2016

Simple and highly-efficient synergistic antimicrobial coatings based on graphene oxide, which could be coated on any substrate irrespective of shape.
Surface modification of aligned CdO nanosheets and their enhanced field emission properties
Authors: Bagal Vivekanand S. , Patil Girish P. , Deore Amol B. , Suryawanshi Sachin R. , Late Dattatray J. , More Mahendra A. , Chavan Padmakar G.
Published: April 2016

Porous aligned CdO nanosheets were grown by simple and cost effective method of thermal annealing. These nanosheets were decorated with Au nanoparticles, and the field emission properties of the Au-decorated aligned CdO nanosheets were enhanced.
A fluorescent turn-on probe for visualizing lysosomes in hypoxic tumor cells
Authors: Luo Sihang , Liu Yingchao , Wang Feiyi , Fei Qiang , Shi Ben , An Jiancai , Zhao Chunchang , Tung Chen-Ho
Published: April 2016

A fluorescent probe localized in lysosomes after reductive cleavage with azoreductase gave strong fluorescence, providing specificity for imaging lysosomes in hypoxic cancer cells.
Strong electrochemiluminescent interactions between carbon nitride nanosheet–reduced graphene oxide nanohybrids and folic acid, and ultrasensitive sensing for folic acid
Authors: Zhou Chen , Chen Yingmei , Shang Pengxiang , Chi Yuwu
Published: April 2016

The electrochemiluminescence from carbon nitride nanosheets can be strongly and selectively quenched by folic acid, resulting in a new and ultrasensitive sensor for folic acid.
Solvent-promoted catalyst-free N-formylation of amines using carbon dioxide under ambient conditions
Authors: Lv Hui , Xing Qi , Yue Chengtao , Lei Ziqiang , Li Fuwei
Published: April 2016

An unprecedented catalyst-free formylation of amines using CO2 and hydrosilanes was developed.
Harnessing NMR relaxation interference effects to characterise supramolecular assemblies
Authors: Karunanithy Gogulan , Cnossen Arjen , Müller Henrik , Peeks Martin D. , Rees Nicholas H. , Claridge Timothy D. W. , Anderson Harry L. , Baldwin Andrew J.
Published: April 2016

Supramolecular assemblies can show unusual splitting patterns in their NMR spectra, with the magnitude of the effect increasing with molecular size. A simple NMR relaxation experiment reveals the origin of the effect and provides information on tumbling rates and local electronic structure.
Single-benzene solid emitters with lasing properties based on aggregation-induced emissions
Authors: Tang Baolei , Liu Huapeng , Li Feng , Wang Yue , Zhang Hongyu
Published: April 2016

Highly efficient single-benzene solid emitters exhibiting aggregation-induced emission (AIE), crystallization-enhanced emission (CEE), as well as amplified spontaneous emission (ASE) have been obtained based on structurally simple ESIPT-active organic molecules.
K- and L-edge X-ray absorption spectrum calculations of closed-shell carbon, silicon, germanium, and sulfur compounds using damped four-component density functional response theory
Authors: Fransson Thomas , Burdakova Daria , Norman Patrick
Published: April 2016

X-ray absorption spectra of carbon, silicon, germanium, and sulfur compounds have been investigated by means of damped four-component density functional response theory.
Evaluating the solid electrolyte interphase formed on silicon electrodes: a comparison of ex situ X-ray photoelectron spectroscopy and in situ neutron reflectometry
Authors: Fears T. M. , Doucet M. , Browning J. F. , Baldwin J. K. S. , Winiarz J. G. , Kaiser H. , Taub H. , Sacci R. L. , Veith G. M.
Published: April 2016

This work details the in situ characterization of the interface between a silicon electrode and an electrolyte using a linear fluorinated solvent molecule.
Understanding the anomalous behavior of Vegard's law in Ce1−xMxO2 (M = Sn and Ti; 0 < x ≤ 0.5) solid solutions
Authors: Baidya Tinku , Bera Parthasarathi , Kröcher Oliver , Safonova Olga , Abdala Paula M. , Gerke Birgit , Pöttgen Rainer , Priolkar Kaustubh R. , Mandal Tapas Kumar
Published: April 2016

A lattice parameter vs. ‘x’ curve in Ce1−xSnxO2 (x = 0.0–0.5) solid solutions is deviated from systematic linearity unlike in Ce1−xZrxO2 due to higher electronegativity of Sn.
Binary breath figures for straightforward and controllable self-assembly of microspherical caps
Authors: Gong Jianliang , Xu Bingang , Tao Xiaoming , Li Lei
Published: April 2016

A binary breath figure approach of using water and methanol has been developed for controllable self-assembly of microspherical caps.
Two novel bi-functional hybrid materials constructed from POMs and a Schiff base with excellent third-order NLO and catalytic properties
Authors: Hu Gonghao , Miao Hao , Mei Hua , Zhou Shuai , Xu Yan
Published: April 2016

The first polyoxometalates modified by a porphyrin-resembling planar Schiff base with excellent third-order NLO and catalytic properties have been successfully developed.
A first-in-class and a fished out anticancer platinum compound: cis-[PtCl2(NH3)2] and cis-[PtI2(NH3)2] compared for their reactivity towards DNA model systems
Authors: Musumeci Domenica , Platella Chiara , Riccardi Claudia , Merlino Antonello , Marzo Tiziano , Massai Lara , Messori Luigi , Montesarchio Daniela
Published: April 2016

The reactivity ofcis-PtI2(NH3)2with selected DNA model systems, in single, double strand or G-quadruplex form, has been studied by circular dichroism, UV-visible spectroscopy and electrospray mass spectrometry using cisplatin as a control.
Simultaneous and selective transformation of glucose to arabinose and nitrosobenzene to azoxybenzene driven by visible-light
Authors: Zhou Baowen , Song Jinliang , Wu Tianbin , Liu Huizhen , Xie Chao , Yang Guanying , Han Buxing
Published: April 2016

The simultaneous and selective conversion of glucose to arabinose and nitrosobenzene to azoxybenzene can be achieved by photocatalysis over Pd/CdS in water under visible light irradiation.
Sterically stabilized fluorescent silver nanoconjugates for optical discrimination of Cu(ii) in real samples and in vitro bioimaging of the Cu(ii) scavenging process in human lymphocytes by atomic force microscopy
Authors: Rasheed Wasia , Shah Muhammad Raza , Kazmi Mehdi Hasan , Shah Kiramat , Afridi Saifullah
Published: April 2016

The nanosensor (Cf-AgNPs) with low cytotoxicity, hemocompatibility and good selectivity for detection of Cu(ii) in real samples.
Engineering of supramolecular photoactive protein architectures: the defined co-assembly of photosystem I and cytochrome c using a nanoscaled DNA-matrix
Authors: Stieger Kai R. , Ciornii Dmitri , Kölsch Adrian , Hejazi Mahdi , Lokstein Heiko , Feifel Sven C. , Zouni Athina , Lisdat Fred
Published: April 2016

We report on the development of an all-biomolecule-based light harvesting 3D architecture on electrodes allowing efficient and tunable photocurrent generation.
Impact of strength and size of donors on the optoelectronic properties of D–π–A sensitizers
Authors: Sivanadanam J. , Ganesan P. , Gao Peng , Nazeeruddin Md. K. , Emeline Alexei , Bahnemann Detlef , Rajalingam R.
Published: April 2016

A series of carbazole based sensitizers have been synthesized to understand the influence of the strength of the donor moiety on the optical, electrochemical and photovoltaic properties.
Surface-functionalizable amphiphilic nanoparticles for pickering emulsions with designer fluid–fluid interfaces
Authors: Pan Ming , Kim Minkyu , Blauch Lucas , Tang Sindy K. Y.
Published: April 2016

This work describes the synthesis of amphiphilic silica nanoparticles with functionalizable surfaces for stabilizing aqueous drops in fluorinated oils, and for enabling the generation of emulsions with tailored interfacial properties.
Morphological, dynamic mechanical, rheological and impact strength properties of the PP/PVB blends: the effect of waste PVB as a toughener
Authors: Zanjanijam Ali Reza , Hakim Shokoufeh , Azizi Hamed
Published: April 2016

In this study, compatibilized PP/PVB blends were prepared and their morphological, dynamic mechanical, rheological and Izod impact strength properties were investigated.
Spectroscopic and electron microscopic analysis of bi-ligand functionalized glycopolymer/FITC–gold nanoparticles
Authors: Dave Kashyap , Malleswara Rao N. Naga , Trinadh Mummuluri , Monisha B. Anu , Sesha Sainath Annadanam V. , Dhayal Marshal
Published: April 2016

We report a strategy to quantify the relative binding affinity of glycopolymers on FITC-AuNP by release of the FITC via self-assembly process and which was improved by introducing a PEG segment to the glycopolymer of similar functionalities.
Palonosetron attenuates 1,2-dimethyl hydrazine induced preneoplastic colon damage through downregulating acetylcholinesterase expression and up-regulating synaptic acetylcholine concentration
Authors: Mishra Rakesh K. , Sammi Shreesh Raj , Rawat Jitendra K. , Roy Subhadeep , Singh Manjari , Gautam Swetlana , Yadav Rajnish K. , Devi Uma , Ansari Mohd Nazam , Saeedan Abdulaziz S. , Saraf Shubhini A. , Pandey Rakesh , Kaithwas Gaurav
Published: April 2016

The present study was undertaken to evaluate the effect of palonosetron (PAL) against 1,2-dimethylhydrazine (DMH)-induced colon cancer.
Screening and characterization for the optimization of CdS-based photocatalysts
Authors: Weng Yu-Ching , Chang Hao
Published: April 2016

The photocatalyst with a precursor composition In0.2–Cd0.8S showed the highest photocurrent under light illumination.
Imine-linked micron-network polymers with high polyethylene glycol uptake for shaped-stabilized phase change materials
Authors: Tang Jia , Fan Shuang , Dong Wenjun , Wang Jingjing , Gao Hongyi , Yang Mu , Yang Ming , Wang Ge
Published: April 2016

Micron-network polymers with high free interstitial space show high adsorption of PEG (up to 85 wt%) for shape-stabilized phase change materials with high energy storage density.
Bimetallic docked covalent organic frameworks with high catalytic performance towards tandem reactions
Authors: Leng Wenguang , Ge Rile , Dong Bin , Wang Chang , Gao Yanan
Published: April 2016

Mn/Pd bimetallic docked covalent organic frameworks showed high catalytic performance towards a tandem reaction.
Fluorescent carbon dots from milk by microwave cooking
Authors: Wang Dan , Zhu Lin , Mccleese Christopher , Burda Clemens , Chen Jian-Feng , Dai Liming
Published: April 2016

Fluorescent carbon dots were synthesized from milk by microwave cooking and used for two-photon excitedin vitrocell imaging.
A field-induced hole generation layer for high performance alternating current polymer electroluminescence and its application to extremely flexible devices
Authors: Lee Ju Han , Cho Sung Hwan , Kim Richard Hahnkee , Jeong Beomjin , Hwang Sun Kak , Hwang Ihn , Kim Kang Lib , Kim Eui Hyuk , Lee Tae-Woo , Park Cheolmin
Published: April 2016

An extremely flexible AC-PEL device was developed with doped PEDOT:PSS.
Oxygen stoichiometry, conductivity and gas sensing properties of BaSnO3
Authors: Alagdal Ibtessam A. , West Anthony R.
Published: April 2016

BaSnO3 powder loses a small amount of oxygen in air at high temperatures leading to significant changes in its electronic conductivity.
Pre‐processing of incomplete spectrum sensing data in spectrum sensing data falsification attacks detection: a missing data imputation approach
Authors: Yao Junnan , Cao Jianjun , Zheng Qibin , Ma Jingang
Published: April 2016

Attacks detection is an important issue in collaborative spectrum sensing (CSS) system of cognitive radio networks. Many approaches are proposed to cope with the malicious behaviour of attackers. In existing works, spectrum sensing data (SSD) received by the fusion centre is generally assumed to be integrated. However, in practical scenarios, the received SSD may be incomplete due to the imperfect reporting channel or specific CSS schemes. The performance of existing attacks detection approaches may degrade especially when the probability of missing data is large. To alleviate this challenge, the authors focus on pre‐processing of incomplete SSD and propose a practical imputation algorithm, which is derived from the maximum a posteriori probability criterion, to fill in the missing values. Simulation results indicate that the proposed algorithm restores the characteristics of the SSD, and mitigate the impacts of missing value on existing attacks detection algorithm effectively.
Distributed energy efficiency beamforming design in multiple‐input‐single‐output interference channels
Authors: Xu Hongbo , Liu Jun , Zhou Aizhi
Published: April 2016

Coordinated beamforming designs based on energy efficiency of multiple‐user interference channels have attracted much attention. The optimisation problem has a fractional form, and is coupled among users, which makes it difficult to be solved directly. A beamforming design for energy‐efficient communication in multiple‐input–single‐output interference channels is studied, and proposes an efficient distributed approach to solve it. A novel method is developed to transform the optimisation problem into a DC (difference of two convex/concave functions) structure. The transformed optimisation problem is approximated by using a separable structure across the users, and this approximated version is solved iteratively. Numerical results show the effectiveness of the authors’ proposed algorithm.
Application of grounded metallic enclosing mesh for expanding rated voltage of dry‐type transformer
Authors: de Oliveira Luiz F. , Cabral Sérgio H.L.
Published: April 2016

Thanks to the awareness of safety, dry‐type transformer has experienced a significant demand, lately. However, a limiting condition for an even more significant increase in its demand is that its maximum rated voltage is about 36 kV, in most of countries. Beyond this limit, dry‐type transformer becomes definitely uneconomical in comparison to oil‐filled transformer because of the expressive increase in dielectric clearance distances and consequent drawbacks. Thus, the aim of this work is to propose a way for overcoming this limit, based on shielding the electric field of the high‐voltage windings of the dry transformer with a grounded metallic mesh. The effectiveness of the proposition is shown whereas most of the undesirable of its consequences are also evaluated. Namely, losses and temperature rise concerns as well as items of standard dielectric tests, which are analysed through computer modelling and simulation. Due to its outstanding importance, analysis of distribution of lightning impulse voltage along the high‐voltage winding is also experimentally performed. The result is a set of key hints given by the authors and to be observed by transformer designers for making real the production of dry‐type transformer with a rated voltage higher than 36 kV.
Design of cascaded all pass network with monotonous group delay response for broadband radio frequency applications
Authors: Keerthan Prabhakar , Vinoy Kalarickaparambil Joseph
Published: April 2016

In this study, an iterative procedure is developed for designing radio frequency circuits with a specified group delay dispersion (GDD) characteristics over a broad bandwidth. Second order all pass networks (APNs) are cascaded systematically over multiple stages to achieve the same. The approach is flexible enough to design circuits for various group delay responses. This is demonstrated using two‐stage APN with both positive and negative slopes of linear and non‐linear group delay responses for a frequency band of 500 MHz–1 GHz. The proposed multi‐stage design procedure is shown to help extend the bandwidth over which a uniform resolution of frequency discrimination is possible. Practical limitations in implementing this circuit are addressed while developing the prototype. The circuit is realised as a surface mount device‐based implementation of modified two‐stage APN. The realised circuit has a GDD of −6 ns/GHz and an insertion loss of 1.2 dB for 500 MHz–1 GHz band. The performance parameters such as GDD, insertion loss and device footprint of the proposed approach are significantly better than previously reported.
Joint estimation of DOA and TOA for MB‐OFDM UWB signals based on frequency‐domain processing
Authors: Hua Meng‐Chang , Liu Hsin‐Chin
Published: April 2016

This study proposes a new joint direction of arrival (DOA) and time of arrival (TOA) estimation (JDTE) scheme for multi‐band orthogonal frequency‐division multiplexing (MB‐OFDM) ultra‐wideband systems with a two‐antenna receiver based on frequency‐domain processing. Prior joint TOA and DOA estimation (JTDE) schemes first measure the TOAs from the received waveforms at all antennas and then obtain the DOA from the TOA measurements. The proposed JDTE method estimates parameters directly from the waveforms received at all antennas, where the channel frequency response associated with the two antenna elements can be considered as a 2D (frequency and space) ‘virtual array’. The DOA is estimated by exploiting the spatial dimension of the virtual array first, and then the TOA is estimated by exploiting the frequency dimension of the virtual array. The use of the virtual array enables the number of resolvable paths to exceed the number of antennas. More importantly, the Cramer–Rao bound (CRB) of DOA estimation that is derived from the received waveforms is significantly lower than that obtained from the TOA metric, and the CRB of the estimated TOA is also slightly lower than that obtained using the JTDE scheme. Numerical simulations verify the superiority of the proposed method.
Geometric joint probabilistic data association approach to ballistic missile warhead tracking using FMCW radar seeker
Authors: Han Seul‐Ki , Ra Won‐Sang , Whang Ick‐Ho , Park Jin Bae
Published: April 2016

This study proposes a new ballistic missile warhead tracking algorithm for enhancing the anti‐ballistic capability of a wideband frequency‐modulated continuous‐wave (FMCW) radar seeker. Under the assumption that the target has a single dominant scattering point, the existing FMCW radars usually adopt the peak tracking algorithm which tracks the scattering point with maximum power in frequency spectra in order to calculate its range/range rate information. However, this method is not applicable for ballistic target tracking using wideband FMCW with high range resolution. This is because the return echoes of ballistic target obtained from wideband FMCW radar seeker are generally represented by many scattering points and, moreover, the most significant scattering point often does not appear at the warhead section of concern. To overcome this limitation, an inventive data association scheme is newly devised by exploiting the geometric constraints. This constraints is derived from the observation that the geometric relation between the scattering points corresponding to the warhead and body sections tends to be roughly determined by the velocity vector of the ballistic missile. Since it could be used for evaluating association hypotheses, the proposed geometric data association tracking filter can drastically improve the warhead tracking performance in practice. Through computer simulations, the effectiveness of the proposed method is demonstrated.
Direction of arrival estimation using array of antennas for low‐altitude targets in multi‐path environment
Authors: Akhavan Saeed , Bahabadi Mehdi Akhavan , Norouzi Yaser , Lolaee Hosein
Published: April 2016

The multi‐path phenomenon can degrade the direction estimation of arrival in radar systems. Without considering this phenomenon, it is possible to consider the multi‐path signal in place of the true signal. In this study, a practical model is developed for radar signals received in flat areas such as deserts. After the modelling process including the presentation of received signals and their formulation, the authors suggest the maximum likelihood (ML) decision to estimate the elevation angle of the targets. Afterwards, by considering the relevant issues, they promote the ML method over the maximum a posteriori decision and the windowing decision. This model and its estimation are very useful in practical applications, particularly in low peak power and low probability of intercept radars.
One‐step in‐situ fabrication of silver‐modified Cu2O crystals with enhanced visible photocatalytic activity
Authors: Li Junqi , Sun Long , Yan Ying , Zhu Zhenfeng
Published: April 2016

Silver‐modified cuprous oxide (Cu2O) crystals (SMCCs) were successfully created by a facile one‐step in‐situ Ag‐loading reaction under room temperature. The samples were studied by X‐ray diffraction, scanning electron microscopy, UV‐vis diffuse reflectance spectra and transmission electron microscopy. The photocatalytic performance of the SMCCs were estimated by using methyl orange aqueous solution as a standard pollutant under visible light irradiation. As a result, the SMCCs show a higher photocatalytic activity than the pure phase Cu2O. The silver nanoparticles which adhered on the surface of Cu2O of different size and content can greatly effects the photocatalytic efficiency. The enhanced photocatalytic activity owed to the effective charge transfer of excited electron‐hole pairs by loading Ag.
Energy dissipation of quantum‐dot cellular automata logic gates
Authors: Rahimi Ehsan
Published: April 2016

Quantum‐dot cellular automata (QCA) is a new paradigm in nanoelectronics, where binary information is represented by charge configuration in cells. Ideal QCA logic gates are thought to be dissipationless, since there is no intercell charge transfer and no current flows out of cells. This work presents that these gates dissipate energy and compare energy consumptions of conventional QCA logic gates in electrostatic and thermodynamic approaches. The results show that increasing the number of inputs, concentration of the geometry and the unbalanced numbers of ‘0’ and ‘1’ output states in the gate's truth table add to the energy dissipation of a QCA gate.
Physics‐based simulation study of high‐performance gallium arsenide phosphide–indium gallium arsenide tunnel field‐effect transistor
Authors: Raad Bhagwan Ram , Sharma Dheeraj , Nigam Kaushal , Kondekar Pravin
Published: April 2016

For the first time, this work presents a novel combination of gallium arsenide phosphide (GaAsP) and indium gallium arsenide (InGaAs) as drain/channel and source materials, respectively, of tunnel field‐effect transistor (TFET) for high‐performance ultra‐low‐power applications. With this combination, the ON‐state current of the proposed device is improved ten times as compared with GaAs–Ge TFET; however, the ambipolar current remains equal to the OFF‐state current. It also exhibits a very low threshold voltage (half in amount) as compared with GaAs–Ge TFET. Apart from these, GaAsP–InGaAs TFET shows huge reduction in the subthreshold slope for better switching operation.