bluuebunny/crossref_metadata_2025 huggingface dataset:
Preservation of Archaeal Surface Layer Structure During Mineralization
Authors: Kish Adrienne , Miot Jennyfer , Lombard Carine , Guigner Jean-Michel , Bernard Sylvain , Zirah Séverine , Guyot François
Published: May 2016

Proteinaceous surface layers (S-layers) are highly ordered, crystalline structures commonly found in prokaryotic cell envelopes that augment their structural stability and modify interactions with metals in the environment. While mineral formation associated with S-layers has previously been noted, the mechanisms were unconstrained. Using Sulfolobus acidocaldarius a hyperthermophilic archaeon native to metal-enriched environments and possessing a cell envelope composed only of a S-layer and a lipid cell membrane, we describe a passive process of iron phosphate nucleation and growth within the S-layer of cells and cell-free S-layer “ghosts” during incubation in a Fe-rich medium, independently of metabolic activity. This process followed five steps: (1) initial formation of mineral patches associated with S-layer; (2) patch expansion; (3) patch connection; (4) formation of a continuous mineral encrusted layer at the cell surface; (5) early stages of S-layer fossilization via growth of the extracellular mineralized layer and the mineralization of cytosolic face of the cell membrane. At more advanced stages of encrustation, encrusted outer membrane vesicles are formed, likely in an attempt to remove damaged S-layer proteins. The S-layer structure remains strikingly well preserved even upon the final step of encrustation, offering potential biosignatures to be looked for in the fossil record.
Perceptual conflict during sensorimotor integration processes - a neurophysiological study in response inhibition
Authors: Chmielewski Witold X. , Beste Christian
Published: May 2016

A multitude of sensory inputs needs to be processed during sensorimotor integration. A crucial factor for detecting relevant information is its complexity, since information content can be conflicting at a perceptual level. This may be central to executive control processes, such as response inhibition. This EEG study aims to investigate the system neurophysiological mechanisms behind effects of perceptual conflict on response inhibition. We systematically modulated perceptual conflict by integrating a Global-local task with a Go/Nogo paradigm. The results show that conflicting perceptual information, in comparison to non-conflicting perceptual information, impairs response inhibition performance. This effect was evident regardless of whether the relevant information for response inhibition is displayed on the global, or local perceptual level. The neurophysiological data suggests that early perceptual/ attentional processing stages do not underlie these modulations. Rather, processes at the response selection level (P3), play a role in changed response inhibition performance. This conflict-related impairment of inhibitory processes is associated with activation differences in (inferior) parietal areas (BA7 and BA40) and not as commonly found in the medial prefrontal areas. This suggests that various functional neuroanatomical structures may mediate response inhibition and that the functional neuroanatomical structures involved depend on the complexity of sensory integration processes.
Comparative Mitochondrial Genome Analysis of Eligma narcissus and other Lepidopteran Insects Reveals Conserved Mitochondrial Genome Organization and Phylogenetic Relationships
Authors: Dai Li-Shang , Zhu Bao-Jian , Zhao Yue , Zhang Cong-Fen , Liu Chao-Liang
Published: May 2016

In this study, we sequenced the complete mitochondrial genome of Eligma narcissus and compared it with 18 other lepidopteran species. The mitochondrial genome (mitogenome) was a circular molecule of 15,376 bp containing 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, two ribosomal RNA (rRNA) genes and an adenine (A) + thymine (T) − rich region. The positive AT skew (0.007) indicated the occurrence of more As than Ts. The arrangement of 13 PCGs was similar to that of other sequenced lepidopterans. All PCGs were initiated by ATN codons, except for the cytochrome c oxidase subunit 1 (cox1) gene, which was initiated by the CGA sequence, as observed in other lepidopterans. The results of the codon usage analysis indicated that Asn, Ile, Leu, Tyr and Phe were the five most frequent amino acids. All tRNA genes were shown to be folded into the expected typical cloverleaf structure observed for mitochondrial tRNA genes. Phylogenetic relationships were analyzed based on the nucleotide sequences of 13 PCGs from other insect mitogenomes, which confirmed that E. narcissus is a member of the Noctuidae superfamily.
Engineering the Campylobacter jejuni N-glycan to create an effective chicken vaccine
Authors: Nothaft Harald , Davis Brandi , Lock Yee Ying , Perez-Munoz Maria Elisa , Vinogradov Evgeny , Walter Jens , Coros Colin , Szymanski Christine M.
Published: May 2016

Campylobacter jejuni is a predominant cause of human gastroenteritis worldwide. Source-attribution studies indicate that chickens are the main reservoir for infection, thus elimination of C. jejuni from poultry would significantly reduce the burden of human disease. We constructed glycoconjugate vaccines combining the conserved C. jejuni N-glycan with a protein carrier, GlycoTag, or fused to the Escherichia coli lipopolysaccharide-core. Vaccination of chickens with the protein-based or E. coli-displayed glycoconjugate showed up to 10-log reduction in C. jejuni colonization and induced N-glycan-specific IgY responses. Moreover, the live E. coli vaccine was cleared prior to C. jejuni challenge and no selection for resistant campylobacter variants was observed. Analyses of the chicken gut communities revealed that the live vaccine did not alter the composition or complexity of the microbiome, thus representing an effective and low-cost strategy to reduce C. jejuni in chickens and its subsequent entry into the food chain.
Fungal endophytes of Catharanthus roseus enhance vindoline content by modulating structural and regulatory genes related to terpenoid indole alkaloid biosynthesis
Authors: Pandey Shiv S. , Singh Sucheta , Babu C. S. Vivek , Shanker Karuna , Srivastava N. K. , Shukla Ashutosh K. , Kalra Alok
Published: May 2016

Not much is known about the mechanism of endophyte-mediated induction of secondary metabolite production in Catharanthus roseus. In the present study two fungal endophytes, Curvularia sp. CATDLF5 and Choanephora infundibulifera CATDLF6 were isolated from the leaves of the plant that were found to enhance vindoline content by 229–403%. The isolated endophytes did not affect the primary metabolism of the plant as the maximum quantum efficiency of PSII, net CO2 assimilation, plant biomass and starch content of endophyte-inoculated plants was similar to endophyte-free control plants. Expression of terpenoid indole alkaloid (TIA) pathway genes, geraniol 10-hydroxylase (G10H), tryptophan decarboxylase (TDC), strictosidine synthase (STR), 16-hydoxytabersonine-O-methyltransferase (16OMT), desacetoxyvindoline-4-hydroxylase (D4H), deacetylvindoline-4-O-acetyltransferase (DAT) were upregulated in endophyte-inoculated plants. Endophyte inoculation upregulated the expression of the gene for transcriptional activator octadecanoid-responsive Catharanthus AP2-domain protein (ORCA3) and downregulated the expression of Cys2/His2-type zinc finger protein family transcriptional repressors (ZCTs). The gene for the vacuolar class III peroxidase (PRX1), responsible for coupling vindoline and catharanthine, was upregulated in endophyte-inoculated plants. These endophytes may enhance vindoline production by modulating the expression of key structural and regulatory genes of vindoline biosynthesis without affecting the primary metabolism of the host plant.
Interfacial electrofluidics in confined systems
Authors: Tang Biao , Groenewold Jan , Zhou Min , Hayes Robert A. , Zhou Guofu
Published: May 2016

Electrofluidics is a versatile principle that can be used for high speed actuation of liquid interfaces. In most of the applications, the fundamental mechanism of electro-capillary instability plays a crucial role, yet it’s potential richness in confined fluidic layers has not been well addressed. Electrofluidic displays which are comprised of thin pixelated colored films in a range of architectures are excellent systems for studying such phenomena. In this study we show theoretically and experimentally that confinement leads to the generation of a cascade of voltage dependent modes as a result of the electro-capillary instability. In the course of reconciling theory with our experimental data we have observed a number of previously unreported phenomena such as a significant induction time (several milliseconds) prior to film rupture as well as a rupture location not corresponding to the minimum electric field strength in the case of the standard convex water/oil interface used in working devices. These findings are broadly applicable to a wide range of switchable electrofluidic applications and devices having confined liquid films.
Fatigue related impairments in oculomotor control are prevented by caffeine
Authors: Connell Charlotte J. W. , Thompson Benjamin , Kuhn Gustav , Claffey Michael P. , Duncan Shelley , Gant Nicholas
Published: May 2016

Strenuous exercise can result in an inability of the central nervous system to drive skeletal muscle effectively, a phenomenon known as central fatigue. The impact of central fatigue on the oculomotor system is currently unexplored. Fatigue that originates in the central nervous system may be related to perturbations in the synthesis and metabolism of several neurotransmitters. In this study we examine central fatigue in the oculomotor system after prolonged exercise. The involvement of central neurotransmission was explored by administering caffeine during exercise. Within a double-blind, randomized, repeated measures, crossover design, 11 cyclists consumed a placebo or caffeine solution during 180 min of stationary cycling. Saccadic eye movements were measured using infra-red oculography. Exercise decreased saccade velocity by 8% (placebo trial). This effect was reversed by caffeine, whereby velocity was increased by 11% after exercise. A non-oculomotor perceptual task (global motion processing) was unaffected by exercise. The human oculomotor system is impaired by strenuous exercise of the locomotor system. Caffeine exerts a protective effect on oculomotor control, which could be related to up-regulated central neurotransmission. In addition, cortical processes supporting global motion perception appear to be robust to fatigue.
A controlled double-duration inducible gene expression system for cartilage tissue engineering
Authors: Ma Ying , Li Junxiang , Yao Yi , Wei Daixu , Wang Rui , Wu Qiong
Published: May 2016

Cartilage engineering that combines competent seeding cells and a compatible scaffold is increasingly gaining popularity and is potentially useful for the treatment of various bone and cartilage diseases. Intensive efforts have been made by researchers to improve the viability and functionality of seeding cells of engineered constructs that are implanted into damaged cartilage. Here, we designed an integrative system combining gene engineering and the controlled-release concept to solve the problems of both seeding cell viability and functionality through precisely regulating the anti-apoptotic gene bcl-2 in the short-term and the chondrogenic master regulator Sox9 in the long-term. Both in vitro and in vivo experiments demonstrated that our system enhances the cell viability and chondrogenic effects of the engineered scaffold after introduction of the system while restricting anti-apoptotic gene expression to only the early stage, thereby preventing potential oncogenic and overdose effects. Our system was designed to be modular and can also be readily adapted to other tissue engineering applications with minor modification.
Isoeugenol is a selective potentiator of camptothecin cytotoxicity in vertebrate cells lacking TDP1
Authors: Elsayed Waheba , El-Shafie Lamia , Hassan Mohamed K. , Farag Mohamed A. , El-Khamisy Sherif F.
Published: May 2016

Camptothecin (CPT), a topoisomerase I (TOP1) inhibitor, exhibits anti-tumor activity against a wide range of tumors. Redundancy of TOP1-mediated repair mechanisms is a major challenge facing the efficiency of TOP1-targetting therapies. This study aims to uncover new TOP1 targeting approaches utilising a selection of natural compounds in the presence or absence of tyrosyl DNA phosphodiesterase I (TDP1); a key TOP1-mediated protein-linked DNA break (PDB) repair enzyme. We identify, isoeugenol, a phenolic ether found in plant essential oils, as a potentiator of CPT cytotoxicity in Tdp1 deficient but not proficient cells. Consistent with our cellular data, isoeugenol did not inhibit Tdp1 enzymatic activity in vitro nor it sensitized cells to the PARP1 inhibitor olaparib. However, biochemical analyses suggest that isoeugenol inhibits TDP2 catalytic activity; a pathway that can compensate for the absence of TDP1. Consistent with this, isoeugenol exacerbated etoposide-induced cytotoxicity, which generates TOP2-mediated PDBs for which TDP2 is required for processing. Together, these findings identify isoeugenol as a potential lead compound for developing TDP2 inhibitors and encourage structure-activity relationship studies to shed more light on its utility in drug discovery programs.
Suppression of X-ray-induced dissociation of H2O molecules in dense ice under pressure
Authors: Fukui Hiroshi , Hiraoka Nozomu , Hirao Naohisa , Aoki Katsutoshi , Akahama Yuichi
Published: May 2016

We investigated molecular dissociation induced by 10-keV X-ray irradiation in dense ice at pressures up to 40 GPa at 300 K. The dissociation yield estimated from the oxygen K-edge X-ray Raman spectra, showed that the molecular dissociation was enhanced up to 14 GPa and gradually suppressed on further compression to 40 GPa. The molecular dissociation was detected for a rather narrow pressure span of 2–40 GPa by the X-ray spectroscopy. The pressure variation of the dissociation yield was similar to that observed in the electric conductivity of ice VII and likely interpreted in terms of proton mobility.
State-space models’ dirty little secrets: even simple linear Gaussian models can have estimation problems
Authors: Auger-Méthé Marie , Field Chris , Albertsen Christoffer M. , Derocher Andrew E. , Lewis Mark A. , Jonsen Ian D. , Mills Flemming Joanna
Published: May 2016

State-space models (SSMs) are increasingly used in ecology to model time-series such as animal movement paths and population dynamics. This type of hierarchical model is often structured to account for two levels of variability: biological stochasticity and measurement error. SSMs are flexible. They can model linear and nonlinear processes using a variety of statistical distributions. Recent ecological SSMs are often complex, with a large number of parameters to estimate. Through a simulation study, we show that even simple linear Gaussian SSMs can suffer from parameter- and state-estimation problems. We demonstrate that these problems occur primarily when measurement error is larger than biological stochasticity, the condition that often drives ecologists to use SSMs. Using an animal movement example, we show how these estimation problems can affect ecological inference. Biased parameter estimates of a SSM describing the movement of polar bears (Ursus maritimus) result in overestimating their energy expenditure. We suggest potential solutions, but show that it often remains difficult to estimate parameters. While SSMs are powerful tools, they can give misleading results and we urge ecologists to assess whether the parameters can be estimated accurately before drawing ecological conclusions from their results.
Evaluation of serum nucleoside diphosphate kinase A for the detection of colorectal cancer
Authors: Otero-Estévez Olalla , De Chiara Loretta , Barcia-Castro Leticia , Páez de la Cadena María , Rodríguez-Berrocal Francisco Javier , Cubiella Joaquín , Hernández Vicent , Martínez-Zorzano Vicenta Soledad
Published: May 2016

We previously described the over-expression of nucleoside diphosphate kinase A (NDKA) in tumours and serum from colorectal cancer (CRC) patients, suggesting its use as biomarker. In this study we evaluated the diagnostic accuracy of serum NDKA to detect advanced neoplasia (CRC or advanced adenomas). Furthermore, the performance of NDKA was compared with the faecal immunochemical test (FIT). The study population included a case-control cohort and a screening cohort (511 asymptomatic first-degree relatives of CRC patients that underwent a colonoscopy and a FIT). Serum NDKA was elevated in CRC patients in the case-control cohort (p = 0.002). In the screening cohort, NDKA levels were higher for advanced adenomas (p = 0.010) and advanced neoplasia (p = 0.006) compared to no neoplasia. Moreover, elevated NDKA was associated with severe characteristics of adenomas (≥3 lesions, size ≥ 1 cm or villous component). Setting specificity to 85%, NDKA showed a sensitivity of 30.19% and 29.82% for advanced adenomas and advanced neoplasia, respectively. NDKA combined with FIT (100 ng/mL cut-off) detected advanced adenomas and advanced neoplasia with 45.28% and 49.12% sensitivity, with specificity close to 90%. The combination of serum NDKA and FIT can improve the detection of advanced neoplasia, mainly for lesions located on the proximal colon, in asymptomatic individuals with CRC family-risk.
A novel species of torque teno mini virus (TTMV) in gingival tissue from chronic periodontitis patients
Authors: Zhang Yu , Li Fei , Shan Tong-Ling , Deng Xutao , Delwart Eric , Feng Xi-Ping
Published: May 2016

A new species of torque teno mini virus, named TTMV-222, was detected in gingival tissue from periodontitis patients using a viral metagenomics method. The 2803-nucleotide genome of TTMV-222 is closely related to TTMV1-CBD279, with 62.6% overall nucleotide similarity. Genetic analyses of the new virus genome revealed a classic genomic organization but a weak identity with known sequences. The prevalence of TTMV-222 in the periodontitis group (n = 150) was significantly higher than that in the healthy group (n = 150) (p = 0.032), suggesting that the new virus may be associated with inflammation in chronic periodontitis patients. However, this finding requires further investigation.
Vitamin D expenditure is not altered in pregnancy and lactation despite changes in vitamin D metabolite concentrations
Authors: Jones Kerry S , Assar Shima , Prentice Ann , Schoenmakers Inez
Published: May 2016

Pregnancy and lactation are associated with changes in vitamin D and calcium metabolism but the impact of these changes on vitamin D expenditure is unknown. We measured plasma 25(OH)D3 half-life with a stable-isotope tracer and investigated relationships with vitamin D metabolites in pregnant, lactating and ‘non-pregnant, non-lactating’ (NPNL) women. Vitamin D metabolites, vitamin D binding protein (DBP), PTH and 25(OH)D3 half-life were measured in third-trimester pregnant women (n22) and repeated during lactation 12 weeks post-partum (n14) and twice in NPNL women (n23 and n10, respectively) in rural Gambia where calcium intakes are low with little seasonality in UVB-exposure. 25(OH)D3 half-life was not significantly different between groups (mean(SD): 20.6(6.8), 22.6(7.7), 18.0(4.7) and 17.7(9.5) days in pregnant, lactating and NPNL women, respectively). Plasma 25(OH)D3, 1,25(OH)2D, and DBP were higher in pregnancy, and calculated free-25(OH)D3 and PTH were lower (P < 0.05). In lactation, 25(OH)D3 and 24,25(OH)2D3 were lower compared to pregnant (P < 0.001, P = 0.02) and NPNL women (P = 0.04, P = 0.07). Significant associations were observed between half-life and 25(OH)D3 (+ve) in pregnancy, and in all groups between 25(OH)D3 and free-25(OH)D3 (+ve) and PTH and 25(OH)D3 (−ve) (P < 0.0001). These data suggest that adaptive changes in pregnancy and lactation occur that prevent pronounced changes in vitamin D expenditure.
Paradoxical activation of MEK/ERK signaling induced by B-Raf inhibition enhances DR5 expression and DR5 activation-induced apoptosis in Ras-mutant cancer cells
Authors: Oh You-Take , Deng Jiusheng , Yue Ping , Sun Shi-Yong
Published: May 2016

B-Raf inhibitors have been used for the treatment of some B-Raf–mutated cancers. They effectively inhibit B-Raf/MEK/ERK signaling in cancers harboring mutant B-Raf, but paradoxically activates MEK/ERK in Ras-mutated cancers. Death receptor 5 (DR5), a cell surface pro-apoptotic protein, triggers apoptosis upon ligation with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) or aggregation. This study focused on determining the effects of B-Raf inhibition on DR5 expression and DR5 activation-induced apoptosis in Ras-mutant cancer cells. Using chemical and genetic approaches, we have demonstrated that the B-Raf inhibitor PLX4032 induces DR5 upregulation exclusively in Ras-mutant cancer cells; this effect is dependent on Ras/c-Raf/MEK/ERK signaling activation. PLX4032 induces DR5 expression at transcriptional levels, largely due to enhancing CHOP/Elk1-mediated DR5 transcription. Pre-exposure of Ras-mutated cancer cells to PLX4032 sensitizes them to TRAIL-induced apoptosis; this is also a c-Raf/MEK/ERK-dependent event. Collectively, our findings highlight a previously undiscovered effect of B-Raf inhibition on the induction of DR5 expression and the enhancement of DR5 activation-induced apoptosis in Ras-mutant cancer cells and hence may suggest a novel therapeutic strategy against Ras-mutated cancer cells by driving their death due to DR5-dependent apoptosis through B-Raf inhibition.
Genome-wide gene-based analysis suggests an association between Neuroligin 1 (NLGN1) and post-traumatic stress disorder
Authors: Kilaru V , Iyer S V , Almli L M , Stevens J S , Lori A , Jovanovic T , Ely T D , Bradley B , Binder E B , Koen N , Stein D J , Conneely K N , Wingo A P , Smith A K , Ressler K J
Published: May 2016

Post-traumatic stress disorder (PTSD) develops in only some people following trauma exposure, but the mechanisms differentially explaining risk versus resilience remain largely unknown. PTSD is heritable but candidate gene studies and genome-wide association studies (GWAS) have identified only a modest number of genes that reliably contribute to PTSD. New gene-based methods may help identify additional genes that increase risk for PTSD development or severity. We applied gene-based testing to GWAS data from the Grady Trauma Project (GTP), a primarily African American cohort, and identified two genes (NLGN1 and ZNRD1-AS1) that associate with PTSD after multiple test correction. Although the top SNP from NLGN1 did not replicate, we observed gene-based replication of NLGN1 with PTSD in the Drakenstein Child Health Study (DCHS) cohort from Cape Town. NLGN1 has previously been associated with autism, and it encodes neuroligin 1, a protein involved in synaptogenesis, learning, and memory. Within the GTP dataset, a single nucleotide polymorphism (SNP), rs6779753, underlying the gene-based association, associated with the intermediate phenotypes of higher startle response and greater functional magnetic resonance imaging activation of the amygdala, orbitofrontal cortex, right thalamus and right fusiform gyrus in response to fearful faces. These findings support a contribution of the NLGN1 gene pathway to the neurobiological underpinnings of PTSD.
Cyclic peptide-based potent human SIRT6 inhibitors
Authors: Liu Jiajia , Zheng Weiping
Published: May 2016

Six side chain-to-side chain cyclic pentapeptides (4–9) harboring a central Nε-dodecyl (or tetradecyl)-thiocarbamoyl-lysine residue all behaved as highly potent (IC50 ∼ 256–495 nM) inhibitors against human SIRT6-catalyzed deacylation reaction.
Self-assembly preparation of gold nanoparticle decorated 1-pyrenemethylamine functionalized graphene oxide–carbon nanotube composites for highly sensitive detection of nitrite
Authors: Rao Dejiang , Sheng Qinglin , Zheng Jianbin
Published: May 2016

Graphene oxide–multiwalled carbon nanotube–(1-pyrenemethylamine)–gold nanocomposites were synthesized by a simple and attractive self-assembly strategy using 1-pyrenemethylamine as a coupling agent.
Powering up the molecular therapy of RNA interference by novel nanoparticles
Authors: Liao Wenzhen , Li Wen , Zhang Tiantian , Kirberger Micheal , Liu Jun , Wang Pei , Chen Wei , Wang Yong
Published: May 2016

With more suitable for disease treatment due to reduced cellular toxicity, higher loading capacity, and better biocompatibility, nanoparticle-based siRNA delivery systems have proved to be more potent, higher specific and less toxic than the traditional drug therapy.
Antibody-free detection of protein phosphorylation using intrinsic peroxidase-like activity of platinum/carbon dot hybrid nanoparticles
Authors: Wang Yuzhen , Qi Wenjin , Song Yujun
Published: May 2016

Platinum and carbon dot hybrid nanomaterials are prepared for visualized detection of phosphoproteins without the need for antibodies or enzymes.
Comb-assisted cavity ring-down spectroscopy of a buffer-gas-cooled molecular beam
Authors: Santamaria Luigi , Sarno Valentina Di , Natale Paolo De , Rosa Maurizio De , Inguscio Massimo , Mosca Simona , Ricciardi Iolanda , Calonico Davide , Levi Filippo , Maddaloni Pasquale
Published: May 2016

We demonstrate continuous-wave cavity ring-down spectroscopy of a partially hydrodynamic molecular beam emerging from a buffer-gas-cooling source.
Flexibilities of isoindoline-derived spin labels for nucleic acids by orientation selective PELDOR
Authors: Erlenbach N. , Endeward B. , Schöps P. , Gophane D. B. , Sigurdsson S. Th. , Prisner T. F.
Published: May 2016

The conformational flexibility of new isoindoline-derived spin labels for nucleic acid have been analyzed by multi-frequency/multi-field PELDOR spectroscopy.
Large amplitude motion of the acetylene molecule within acetylene–neon complexes hosted in helium droplets
Authors: Briant M. , Mengesha E. , de Pujo P. , Gaveau M.-A. , Soep B. , Mestdagh J.-M. , Poisson L.
Published: May 2016

This work examines how the non-superfluid component of helium droplets hosting a C2H2–Ne complex affects the hindered rotation of C2H2 within the complex.
Ni(ii)/Cu(ii)/Zn(ii) 5,5-diethylbarbiturate complexes with 1,10-phenanthroline and 2,2′-dipyridylamine: synthesis, structures, DNA/BSA binding, nuclease activity, molecular docking, cellular uptake, cytotoxicity and the mode of cell death
Authors: Yilmaz Veysel T. , Icsel Ceyda , Suyunova Feruza , Aygun Muhittin , Aztopal Nazlihan , Ulukaya Engin
Published: May 2016

DNA/BSA binding and anticancer properties of new Ni(ii), Cu(ii) and Zn(ii) 5,5-diethylbarbiturate complexes were evaluated.
Inhibition of LPS-induced inflammatory mediators by 3-hydroxyanthranilic acid in macrophages through suppression of PI3K/NF-κB signaling pathways
Authors: Lee Kyoungran , Kwak Jong-Hwan , Pyo Suhkneung
Published: May 2016

Many tryptophan metabolites have immunomodulatory effects on various immune cells.
Electron transfer in tetramethylbiphosphinine complexes of Cp*2Yb and Cp*2Sm
Authors: Jaoul Arnaud , Clavaguéra Carine , Nocton Grégory
Published: May 2016

How to make sure an electron is really transferred to a tmbp ligand?
Efficient catalytic α-trifluoromethylthiolation of aldehydes
Authors: Hu Liqiang , Wu Minghu , Wan Huixin , Wang Jian , Wang Gangqiang , Guo Haibin , Sun Shaofa
Published: May 2016

An efficient organocatalytic method for α-trifluoromethylthiolation of aldehydes has been developed.
Transparent superhydrophobic coatings from amphiphilic-fluorinated block copolymers synthesized by aqueous polymerization-induced self-assembly
Authors: Ouhib Farid , Dirani Ali , Aqil Abdelhafid , Glinel Karine , Nysten Bernard , Jonas Alain M. , Jerôme Christine , Detrembleur Christophe
Published: May 2016

Preparation of transparent and superhydrophobic coatings by co-deposition of an aqueous solution of an amphiphilic fluorinated block copolymer with silica was developed.
Theoretical studies on oxidation-switchable second-order nonlinear optical responses of Metallosalen-Keggin polyoxometalate derivatives
Authors: Ma Teng-Ying , Zhang Ting , Zhu Bo , Yan Li-Kai , Su Zhong-Min
Published: May 2016

The one-electron oxidation effect on the first hyperpolarizability of Metallosalen-Keggin polyoxometalate derivatives.
Tacrine-allyl/propargylcysteine–benzothiazole trihybrids as potential anti-Alzheimer's drug candidates
Authors: Hiremathad Asha , Chand Karam , Esteves A. Raquel , Cardoso Sandra M. , Ramsay Rona R. , Chaves Sílvia , Keri Rangappa S. , Santos M. Amélia
Published: May 2016

Eight novel trihybrids as potential anti-Alzheimer's drugs showed high AChEI and anti-Aβ aggregation capacity, moderate anti-ROS activity and low MAO inhibition.
Low operating temperature toluene sensor based on novel α-Fe2O3/SnO2 heterostructure nanowire arrays
Authors: Wang Tianshuang , Huang Zhangshu , Yu Zhangduo , Wang Boqun , Wang Hui , Sun Peng , Suo Hui , Gao Yuan , Sun Yanfeng , Li Tie , Lu Geyu
Published: May 2016

A novel low operating temperature toluene sensor based on α-Fe2O3/SnO2 heterostructure nanowires arrays by combining USP and hydrothermal strategy.
Development of a macroporous-spherical polyanionic compound (TiO)2P2O7 as a novel anode material for sodium ion batteries
Authors: Zhang Shuming , Liu Yu , Zhang Na , Zhao Kuan , Yang Jianhua , He Shiyang
Published: May 2016

The phosphate-based polyanionic compound with the formula (TiO)2P2O7 was synthesized by a simple precipitation method with a soft template as a novel anode material for sodium ion batteries for the first time.
Synchronization of conformational chirality in mixtures of achiral bent-core molecules
Authors: Anjali S. , Pratibha R.
Published: May 2016

SEM images and frequency variation of ε′′ in PDMBC with flat layers, M50 and M20 with respectively weak and strong layer deformation.
An efficient ultrasonic-mediated one-pot synthesis of 2,3,6,7,9-pentaazabicyclo[3.3.1]nonanes via a N,N-dimethylformamide dimethylacetal catalyzed Mannich-like reaction
Authors: Behbehani Haider , Ibrahim Hamada Mohamed
Published: May 2016

A novel and straightforward method for one-pot synthesis of functionalized 2,3,6,7,9-pentaazabicyclo[3.3.1]nonane derivatives has been developed.
The investigation of non-noble metal doped mesoporous cobalt oxide catalysts for the water–gas shift reaction
Authors: Na Hyun-Suk , Ahn Chang-Il , Jha Ajay , Park Kyung Soo , Jang Won-Jun , Shim Jae-Oh , Jeong Dae-Woon , Roh Hyun-Seog , Bae Jong Wook
Published: May 2016

In this study, we report an investigation of the low temperature water–gas shift (LT-WGS) reaction over a series of non-noble metal doped (Me = Mn, Fe, Co, and Ni) mesoporous Co3O4 catalysts.
Considerable effect of dimethylimidazolium dimethylphosphate in cinnamon essential oil extraction by hydrodistillation
Authors: Pistelli Luisa , Giovanelli Silvia , Margari Piero , Chiappe Cinzia
Published: May 2016

This paper reports an improved essential oil extraction process by hydrodistillation based on the use of an IL in the pre-treatment step.
Top-down dispersion meets bottom-up synthesis: merging ultranano silicon and graphene nanosheets for superior hybrid anodes for lithium-ion batteries
Authors: Huang Yao-Hui , Bao Qi , Duh Jenq-Gong , Chang Chih-Tse
Published: May 2016

An advanced “top-down dispersion meets bottom-up synthesis” leads to high performance graphene-based Si LIB anodes. All the reported manufacturing processes are designed to be industrially feasible.
Thermosensitive Cu2O–PNIPAM core–shell nanoreactors with tunable photocatalytic activity
Authors: Jia He , Roa Rafael , Angioletti-Uberti Stefano , Henzler Katja , Ott Andreas , Lin Xianzhong , Möser Jannik , Kochovski Zdravko , Schnegg Alexander , Dzubiella Joachim , Ballauff Matthias , Lu Yan
Published: May 2016

Cu2O–PNIPAM core–shell nanoparticles have been synthesized to protect Cu2O nanocubes from oxidation and applied as active “nanoreactors” with tunable catalytic activity with temperature for the photocatalytic decomposition of methyl orange.
Improving performance in CdTe/CdSe nanocrystals solar cells by using bulk nano-heterojunctions
Authors: Xie Ya , Tan Qiongxuan , Zhang Zhitao , Lu Kuankuan , Li Miaozi , Xu Wei , Qin Donghuan , Zhang Yangdong , Hou Lintao , Wu Hongbin
Published: May 2016

In this study, CdTe/CdSe NCs BNH solar cells with PCE of 6.25% were successfully fabricated in an inverted structure configuration ITO/ZnO/CdSe/CdSe:CdTe/CdTe/Au by a solution process.
A 7-methoxytacrine–4-pyridinealdoxime hybrid as a novel prophylactic agent with reactivation properties in organophosphate intoxication
Authors: Nepovimova E. , Korabecny J. , Dolezal R. , Nguyen T. D. , Jun D. , Soukup O. , Pasdiorova M. , Jost P. , Muckova L. , Malinak D. , Gorecki L. , Musilek K. , Kuca Kamil
Published: May 2016

Chemical warfare agents constitute an increasing threat to both military and civilian populations. Therefore, effective prophylactic approaches are urgently needed. Herein, we present a novel hybrid compound which is able not only to keep acetylcholinesterase resistant to organophosphate (OP) inhibitors, but also to serve as an enzyme reactivator in the case of OP intoxication.
Zero‐voltage zero‐current switching DC/DC converter with high step‐up and high efficiency
Authors: Lin Xuefeng , Xu Jianping , Zhou Xiang , Zhou Guohua
Published: May 2016

Based on soft‐switched continuous conduction mode boost converter, a zero‐voltage zero‐current switching DC/DC converter is proposed by introducing a flyback‐unit and a voltage‐double‐unit. The proposed converter can achieve high voltage gain without operating at extreme high duty cycle. Moreover, by replacing the output diode of conventional boost converter with an active switch, zero‐voltage‐switched turn‐on of switches and zero‐current‐switched turn‐off of diodes can be achieved, which reduce switching loss and alleviate reverse‐recovery problem of diodes. Furthermore, the energy in leakage inductor can be transferred into the output of the converter to improve the efficiency. The operating characteristics and the voltage gain of the proposed converter are analysed. Experimental results of a 100 W prototype are provided to verify the theoretical analysis results.
Optimal power scheduling of renewable energy systems in microgrids using distributed energy storage system
Authors: Singh Shakti , Singh Mukesh , Kaushik Subhash Chandra
Published: May 2016

The rapid depletion of fossil fuel resources and increase in demand of electricity has renewed interest in micro‐grids (MGs). Incorporating renewable energy sources (RESs) and storage devices into MG could play a vital role in enhancing the reliability of the system. However, due to the intermittent nature of RESs, voltage fluctuations may occur in the system. Therefore, storage devices can be the most viable option to handle the intermittent issues of RESs. Nowadays, handling a group of batteries with different ratings in the MG has been a major focus of research. The batteries with different ratings used for storage as well as grid support is termed as a distributed energy storage system. This work mainly emphasises on optimal power management of an MG by controlling the charging and discharging rates of individual battery. A droop‐based controller is proposed for optimal power management of batteries. An aggregator has been suggested at the MG which distributes the power among the various charging stations (CSs) and each CS finally distributes the power among the individual batteries based on droop participation factor. Moreover, the charging and discharging rates of batteries are controlled to achieve the desired power flow between the MG and CSs. The simulation results show the efficacy of the controller to meet the desired power at the MG. The proposed system is compared with an existing system to prove the efficacy of the proposed controller. Moreover, all the critical cases have been considered, such as the sudden failure of any generating unit. It has been observed that due to sudden failure of any generating unit, CSs manages power of the MG by altering charging and discharging rate of the batteries.
Simplified accelerated particle swarm optimisation algorithm for efficient maximum power point tracking in partially shaded photovoltaic systems
Authors: Rajendran Subha , Srinivasan Himavathi
Published: May 2016

Photovoltaic (PV) systems are becoming increasingly popular due to its advantages such as abundant availability, eco‐friendly nature and low maintenance requirement. In large PV arrays occurrence of partial shading is very high. Under partially shaded conditions the P–V curve of the array exhibits multiple peaks and the conventional maximum power point tracking (MPPT) algorithms fail to detect the global peak. Recently particle swarm optimisation (PSO) technique has gained significant attention due to its ability to locate the maximum power point for any type of P–V curve. Many variations of PSO algorithm to improve its effectiveness are also available. One variation is the accelerated PSO (APSO) where the algorithm is modified to simplify the search process. This study proposes a simple and efficient MPPT for a PV system using a modified APSO algorithm. The proposed algorithm has been validated through simulation and experimental setup for different shading patterns.
Semiclassical stochastic mechanics for the Coulomb potential with applications to modelling dark matter
Authors: Neate Andrew , Truman Aubrey
Published: May 2016

Little is known about dark matter particles save that their most important interactions with ordinary matter are gravitational and that, if they exist, they are stable, slow moving and relatively massive. Based on these assumptions, a semiclassical approximation to the Schrödinger equation under the action of a Coulomb potential should be relevant for modelling their behaviour. We investigate the semiclassical limit of the Schrödinger equation for a particle of mass M under a Coulomb potential in the context of Nelson’s stochastic mechanics. This is done using a Freidlin-Wentzell asymptotic series expansion in the parameter ϵ=ħ/M for the Nelson diffusion. It is shown that for wave functions ψ ∼ exp((R + iS)/ϵ2) where R and S are real valued, the ϵ = 0 behaviour is governed by a constrained Hamiltonian system with Hamiltonian Hr and constraint Hi = 0 where the superscripts r and i denote the real and imaginary parts of the Bohr correspondence limit of the quantum mechanical Hamiltonian, independent of Nelson’s ideas. Nelson’s stochastic mechanics is restored in dealing with the nodal surface singularities and by computing (correct to first order in ϵ) the relevant diffusion process in terms of Jacobi fields thereby revealing Kepler’s laws in a new light. The key here is that the constrained Hamiltonian system has just two solutions corresponding to the forward and backward drifts in Nelson’s stochastic mechanics. We discuss the application of this theory to modelling dark matter particles under the influence of a large gravitating point mass.
Eddy current-shielded x-space relaxometer for sensitive magnetic nanoparticle characterization
Authors: Bauer L. M. , Hensley D. W. , Zheng B. , Tay Z. W. , Goodwill P. W. , Griswold M. A. , Conolly S. M.
Published: May 2016

The development of magnetic particle imaging (MPI) has created a need for optimized magnetic nanoparticles. Magnetic particle relaxometry is an excellent tool for characterizing potential tracers for MPI. In this paper, we describe the design and construction of a high-throughput tabletop relaxometer that is able to make sensitive measurements of MPI tracers without the need for a dedicated shield room.
Synchrotron-based valence shell photoionization of CH radical
Authors: Gans B. , Holzmeier F. , Krüger J. , Falvo C. , Röder A. , Lopes A. , Garcia G. A. , Fittschen C. , Loison J.-C. , Alcaraz C.
Published: May 2016

We report the first experimental observations of X+ 1Σ+←X 2Π and a+ 3Π←X 2Π single-photon ionization transitions of the CH radical performed on the DESIRS beamline at the SOLEIL synchrotron facility. The radical was produced by successive hydrogen-atom abstractions on methane by fluorine atoms in a continuous microwave discharge flow tube. Mass-selected ion yields and photoelectron spectra were recorded as a function of photon energy using a double imaging photoelectron/photoion coincidence spectrometer. The ion yield appears to be strongly affected by vibrational and electronic autoionizations, which allow the observation of high Rydberg states of the neutral species. The photoelectron spectra enable the first direct determinations of the adiabatic ionization potential and the energy of the first triplet state of the cation with respect to its singlet ground state. This work also brings valuable information on the complex electronic structure of the CH radical and its cation and adds new observations to complement our understanding of Rydberg states and autoionization processes.
Oscillator metrology with software defined radio
Authors: Sherman Jeff A. , Jördens Robert
Published: May 2016

Analog electrical elements such as mixers, filters, transfer oscillators, isolating buffers, dividers, and even transmission lines contribute technical noise and unwanted environmental coupling in time and frequency measurements. Software defined radio (SDR) techniques replace many of these analog components with digital signal processing (DSP) on rapidly sampled signals. We demonstrate that, generically, commercially available multi-channel SDRs are capable of time and frequency metrology, outperforming purpose-built devices by as much as an order-of-magnitude. For example, for signals at 10 MHz and 6 GHz, we observe SDR time deviation noise floors of about 20 fs and 1 fs, respectively, in under 10 ms of averaging. Examining the other complex signal component, we find a relative amplitude measurement instability of 3 × 10−7 at 5 MHz. We discuss the scalability of a SDR-based system for simultaneous measurement of many clocks. SDR’s frequency agility allows for comparison of oscillators at widely different frequencies. We demonstrate a novel and extreme example with optical clock frequencies differing by many terahertz: using a femtosecond-laser frequency comb and SDR, we show femtosecond-level time comparisons of ultra-stable lasers with zero measurement dead-time.
Stochastic modelling of intermittent fluctuations in the scrape-off layer: Correlations, distributions, level crossings, and moment estimation
Authors: Garcia O. E. , Kube R. , Theodorsen A. , Pécseli H. L.
Published: May 2016

A stochastic model is presented for intermittent fluctuations in the scrape-off layer of magnetically confined plasmas. The fluctuations in the plasma density are modeled by a super-position of uncorrelated pulses with fixed shape and duration, describing radial motion of blob-like structures. In the case of an exponential pulse shape and exponentially distributed pulse amplitudes, predictions are given for the lowest order moments, probability density function, auto-correlation function, level crossings, and average times for periods spent above and below a given threshold level. Also, the mean squared errors on estimators of sample mean and variance for realizations of the process by finite time series are obtained. These results are discussed in the context of single-point measurements of fluctuations in the scrape-off layer, broad density profiles, and implications for plasma–wall interactions due to the transient transport events in fusion grade plasmas. The results may also have wide applications for modelling fluctuations in other magnetized plasmas such as basic laboratory experiments and ionospheric irregularities.
Noise induced stabilization of chaotic free-running laser diode
Authors: Virte Martin
Published: May 2016

In this paper, we investigate theoretically the stabilization of a free-running vertical-cavity surface-emitting laser exhibiting polarization chaos dynamics. We report the existence of a boundary isolating the chaotic attractor on one side and a steady-state on the other side and identify the unstable periodic orbit playing the role of separatrix. In addition, we highlight a small range of parameters where the chaotic attractor passes through this boundary, and therefore where chaos only appears as a transient behaviour. Then, including the effect of spontaneous emission noise in the laser, we demonstrate that, for realistic levels of noise, the system is systematically pushed over the separating solution. As a result, we show that the chaotic dynamics cannot be sustained unless the steady-state on the other side of the separatrix becomes unstable. Finally, we link the stability of this steady-state to a small value of the birefringence in the laser cavity and discuss the significance of this result on future experimental work.
A potential thermal dynamo and its astrophysical applications
Authors: Lingam Manasvi , Mahajan Swadesh M.
Published: May 2016

It is shown that thermal turbulence, not unlike the standard kinetic and magnetic turbulence, can be an effective driver of a mean-field dynamo. In simple models, such as hydrodynamics and magnetohydrodynamics, both vorticity and induction equations can have strong thermal drives that resemble the α and γ effects in conventional dynamo theories; the thermal drives are likely to be dominant in systems that are endowed with subsonic, low-β turbulence. A pure thermal dynamo is quite different from the conventional dynamo in which the same kinetic/magnetic mix in the ambient turbulence can yield a different ratio of macroscopic magnetic/vortical fields. The possible implications of the similarities and differences between the thermal and non-thermal dynamos are discussed. The thermal dynamo is shown to be highly important in the stellar and planetary context, and yields results broadly consistent with other theoretical and experimental approaches.
Oxide or carbide nanoparticles synthesized by laser ablation of a bulk Hf target in liquids and their structural, optical, and dielectric properties
Authors: Semaltianos N. G. , Friedt J.-M. , Chassagnon R. , Moutarlier V. , Blondeau-Patissier V. , Combe G. , Assoul M. , Monteil G.
Published: May 2016

Laser ablation of a bulk Hf target in deionized (DI) water, ethanol, or toluene was carried out for the production of nanoparticles' colloidal solutions. Due to the interaction of the ablation plasma plume species with the species which are produced by the liquid decomposition at the plume-liquid interface, hafnia (HfO2) nanoparticles are synthesized in DI water, hafnium carbide (HfC) nanoparticles in toluene, and a mixture of these in ethanol. The hafnia nanoparticles are in the monoclinic low temperature phase and in the tetragonal and fcc high temperature phases. Their size distribution follows log-normal function with a median diameter in the range of 4.3–5.3 nm. Nanoparticles synthesized in DI water have band gaps of 5.6 and 5.4 eV, in ethanol 5.72 and 5.65 eV (using low and high pulse energy), and in toluene 3 eV. The values for the relative permittivity in the range of 7.74–8.90 were measured for hafnia nanoparticles' thin films deposited on substrates by drop-casting (self-assembled layers) in parallel plate capacitor structures.
Anharmonicity in light scattering by optical phonons in GaAs1-xBix
Authors: Joshya R. S. , Rajaji V. , Narayana Chandrabhas , Mascarenhas A. , Kini R. N.
Published: May 2016

We present a Raman spectroscopic study of GaAs1−xBix epilayers grown by molecular beam epitaxy. We have investigated the anharmonic effect on the GaAs-like longitudinal optical phonon mode (LOGaAs′) of GaAs1−xBix for different Bi concentrations at various temperatures. The results are analyzed in terms of the anharmonic damping effect induced by thermal and compositional disorder. We have observed that the anharmonicity increases with Bi concentration in GaAs1−xBix as evident from the increase in the anharmonicity constants. In addition, the anharmonic lifetime of the optical phonon decreases with increasing Bi concentration in GaAs1−xBix.