bluuebunny/crossref_metadata_2025 huggingface dataset:
High glucose levels boost the aggressiveness of highly metastatic cholangiocarcinoma cells via O-GlcNAcylation
Authors: Phoomak Chatchai , Vaeteewoottacharn Kulthida , Silsirivanit Atit , Saengboonmee Charupong , Seubwai Wunchana , Sawanyawisuth Kanlayanee , Wongkham Chaisiri , Wongkham Sopit
Published: March 2017

Increased glucose utilization is a feature of cancer cells to support cell survival, proliferation, and metastasis. An association between diabetes mellitus and cancer progression was previously demonstrated in cancers including cholangiocarcinoma (CCA). This study was aimed to determine the effects of high glucose on protein O-GlcNAcylation and metastatic potentials of CCA cells. Two pairs each of the parental low metastatic and highly metastatic CCA sublines were cultured in normal (5.6 mM) or high (25 mM) glucose media. The migration and invasion abilities were determined and underlying mechanisms were explored. Results revealed that high glucose promoted migration and invasion of CCA cells that were more pronounced in the highly metastatic sublines. Concomitantly, high glucose increased global O-GlcNAcylated proteins, the expressions of vimentin, hexokinase, glucosamine-fructose-6-phosphate amidotransferase (GFAT) and O-GlcNAc transferase of CCA cells. The glucose level that promoted migration/invasion was shown to be potentiated by the induction of GFAT, O-GlcNAcylation and an increase of O-GlcNAcylated vimentin and vimentin expression. Treatment with a GFAT inhibitor reduced global O-GlcNAcylated proteins, vimentin expression, and alleviated cell migration. Altogether, these results suggested the role of high glucose enhanced CCA metastasis via modulation of O-GlcNAcylation, through the expressions of GFAT and vimentin.
The RNAi pathway plays a small part in Wolbachia-mediated blocking of dengue virus in mosquito cells
Authors: Terradas Gerard , Joubert D. Albert , McGraw Elizabeth A.
Published: March 2017

Wolbachia pipientis is an insect endosymbiont known to limit the replication of viruses including dengue and Zika in their primary mosquito vector, Aedes aegypti. Wolbachia is being released into mosquito populations globally in a bid to control the diseases caused by these viruses. It is theorized that Wolbachia’s priming of the insect immune system may confer protection against subsequent viral infection. Other hypotheses posit a role for competition between Wolbachia and viruses for host cellular resources. Using an A. aegypti cell line infected with Wolbachia, we tested the effects of targeting siRNAs against the major innate immune pathways on dengue virus loads. We show that while Wolbachia infection induces genes in the Toll, JAK/STAT and RNAi pathways, only reduced expression of RNAi leads to a rebound of dengue virus loads in Wolbachia-infected cells. The magnitude of the effect explained less than 10% of the total DENV load, demonstrating that blocking must be dependent on other factors in addition to the expression of RNAi. The findings bode well for the long-term stability of blocking given that immunity gene expression would likely be highly plastic and susceptible to rapid evolution.
Dynamics of miRNA transcriptome during gonadal development of zebrafish
Authors: Presslauer Christopher , Tilahun Bizuayehu Teshome , Kopp Martina , Fernandes Jorge M. O. , Babiak Igor
Published: March 2017

Studies in non-teleost vertebrates have found microRNAs (miRNAs) to be essential for proper gonadal development. However, comparatively little is known about their role during gonadal development in teleost fishes. So far in zebrafish, a model teleost, transcript profiling throughout gonadal development has not been established because of a tiny size of an organ in juvenile stages and its poor distinguishability from surrounding tissues. We performed small RNA sequencing on isolated gonads of See-Thru-Gonad line, from the undifferentiated state at 3 weeks post fertilization (wpf) to fully mature adults at 24 wpf. We identified 520 gonadal mature miRNAs; 111 of them had significant changes in abundance over time, while 50 miRNAs were either testis- or ovary-enriched significantly in at least one developmental stage. We characterized patterns of miRNA abundance over time including isomiR variants. We identified putative germline versus gonadal somatic miRNAs through differential small RNA sequencing of isolated gametes versus the whole gonads. This report is the most comprehensive analysis of the miRNA repertoire in zebrafish gonads during the sexual development to date and provides an important database from which functional studies can be performed.
Racial and Ethnic Variation in the Association of Social Integration with Mortality: Ten-year Prospective Population-based US Study
Authors: Barger Steven D. , Uchino Bert N.
Published: March 2017

Substantial data link social relationships with mortality but few studies have examined whether these associations are consistent across racial and ethnic groups. The purpose of the present study was to evaluate the presence and form of the social relationship/mortality association in a representative sample of US Black (n = 4,201), non-Hispanic White (n = 20,217) and Hispanic (n = 5,097) groups. In models adjusted for age, sex, chronic disease, socioeconomic status and smoking social integration was inversely related to ten-year survival in all groups. However, among Whites the association was linear and graded whereas among Blacks the association was linear but was statistically significant only for the highest level of social integration (hazard ratio [HR] = 0.66, 95% confidence interval = 0.47–0.94). A threshold pattern was observed among Hispanics, in that lower mortality risk was found for all social integration categories above the lowest level (HRs from 0.58 to 0.52, P’s < 0.01) and each of the higher social integration categories were in turn equivalent. Received social support was unrelated to mortality across all groups. Higher social integration is associated with a survival advantage for Blacks and Whites. For Hispanics, moderate and high levels of social integration were equally protective.
A Novel Ideal Radionuclide Imaging System for Non-invasively Cell Monitoring built on Baculovirus Backbone by Introducing Sleeping Beauty Transposon
Authors: Lv Jing , Pan Yu , Ju Huijun , Zhou Jinxin , Cheng Dengfeng , Shi Hongcheng , Zhang Yifan
Published: March 2017

Sleeping Beauty (SB) transposon is an attractive tool in stable transgene integration both in vitro and in vivo; and we introduced SB transposon into recombinant sodium-iodide symporter baculovirus system (Bac-NIS system) to facilitate long-term expression of recombinant sodium-iodide symporter. In our study, two hybrid baculovirus systems (Bac-eGFP-SB-NeoR and Bac-NIS-SB-NeoR) were successfully constructed and used to infect U87 glioma cells. After G418 selection screening, the Bac-eGFP-SB-NeoR-U87 cells remained eGFP positive, at the 18th and 196th day post transfection (96.03 ± 0.21% and 97.43 ± 0.81%), while eGFP positive population declined significantly at 18 days in cells transfected with unmodified baculovirus construct. NIS gene expression by Bac-NIS-SB-NeoR-U87 cells was also maintained for 28 weeks as determined by radioiodine uptake assay, reverse transcription-polymerase chain reaction (RT-PCR) and Western Blot (WB) assay. When transplanted in mice, Bac-NIS-SB-NeoR-U87 cells also expressed NIS gene stably as monitored by SPECT imaging for 43 days until the tumor-bearing mice were sacrificed. Herein, we showed that incorporation of SB in Bac-NIS system (hybrid Bac-NIS-SB-NeoR) can achieve a long-term transgene expression and can improve radionuclide imaging in cell tracking and monitoring in vivo.
Finite-size effects on bacterial population expansion under controlled flow conditions
Authors: Tesser Francesca , Zeegers Jos C. H. , Clercx Herman J. H. , Brunsveld Luc , Toschi Federico
Published: March 2017

The expansion of biological species in natural environments is usually described as the combined effect of individual spatial dispersal and growth. In the case of aquatic ecosystems flow transport can also be extremely relevant as an extra, advection induced, dispersal factor. We designed and assembled a dedicated microfluidic device to control and quantify the expansion of populations of E. coli bacteria under both co-flowing and counter-flowing conditions, measuring the front speed at varying intensity of the imposed flow. At variance with respect to the case of classic advective-reactive-diffusive chemical fronts, we measure that almost irrespective of the counter-flow velocity, the front speed remains finite at a constant positive value. A simple model incorporating growth, dispersion and drift on finite-size hard beads allows to explain this finding as due to a finite volume effect of the bacteria. This indicates that models based on the Fisher-Kolmogorov-Petrovsky-Piscounov equation (FKPP) that ignore the finite size of organisms may be inaccurate to describe the physics of spatial growth dynamics of bacteria.
Multi-gigahertz, femtosecond Airy beam optical parametric oscillator pumped at 78 MHz
Authors: Aadhi A. , Sharma Varun , Chaitanya N. Apurv , Samanta G. K.
Published: March 2017

We report a high power ultrafast Airy beam source producing femtosecond pulses at multi-gigahertz (GHz) repetition rate (RR). Based on intra-cavity cubic phase modulation of an optical parametric oscillator (OPO) designed in high harmonic cavity configuration synchronous to a femtosecond Yb-fiber laser operating at 78 MHz, we have produced ultrafast 2D Airy beam at multi-GHz repetition rate through the fractional increment in the cavity length. While small (<1 mm) crystals are used in femtosecond OPOs to take the advantage of broad phase-matching bandwidth, here, we have exploited the extended phase-matching bandwidth of a 50-mm long Magnesium-oxide doped periodically poled LiNbO3 (MgO:PPLN) crystal for efficient generation of ultrafast Airy beam and broadband mid-IR radiation. Pumping the MgO:PPLN crystal of grating period, Λ = 30 μm and crystal temperature, T = 100 °C using a 5-W femtosecond laser centred at 1064 nm, we have produced Airy beam radiation of 684 mW in ~639 fs (transform limited) pulses at 1525 nm at a RR of ~2.5 GHz. Additionally, the source produces broadband idler radiation with maximum power of 510 mW and 94 nm bandwidth at 3548 nm in Gaussian beam profile. Using an indirect method (change in cavity length) we estimate maximum RR of the Airy beam source to be ~100 GHz.
Response inhibition in Attention deficit disorder and neurofibromatosis type 1 – clinically similar, neurophysiologically different
Authors: Bluschke Annet , von der Hagen Maja , Papenhagen Katharina , Roessner Veit , Beste Christian
Published: March 2017

There are large overlaps in cognitive deficits occurring in attention deficit disorder (ADD) and neurodevelopmental disorders like neurofibromatosis type 1 (NF1). This overlap is mostly based on clinical measures and not on in-depth analyses of neuronal mechanisms. However, the consideration of such neuronal underpinnings is crucial when aiming to integrate measures that can lead to a better understanding of the underlying mechanisms. Inhibitory control deficits, for example, are a hallmark in ADD, but it is unclear how far there are similar deficits in NF1. We thus compared adolescent ADD and NF1 patients to healthy controls in a Go/Nogo task using behavioural and neurophysiological measures. Clinical measures of ADD-symptoms were not different between ADD and NF1. Only patients with ADD showed increased Nogo errors and reductions in components reflecting response inhibition (i.e. Nogo-P3). Early perceptual processes (P1) were changed in ADD and NF1. Clinically, patients with ADD and NF1 thus show strong similarities. This is not the case in regard to underlying cognitive control processes. This shows that in-depth analyses of neurophysiological processes are needed to determine whether the overlap between ADD and NF1 is as strong as assumed and to develop appropriate treatment strategies.
A biomimetic gelatin-based platform elicits a pro-differentiation effect on podocytes through mechanotransduction
Authors: Hu Mufeng , Azeloglu Evren U. , Ron Amit , Tran-Ba Khanh-Hoa , Calizo Rhodora C. , Tavassoly Iman , Bhattacharya Smiti , Jayaraman Gomathi , Chen Yibang , Rabinovich Vera , Iyengar Ravi , Hone James C. , He John C. , Kaufman Laura J.
Published: March 2017

Using a gelatin microbial transglutaminase (gelatin-mTG) cell culture platform tuned to exhibit stiffness spanning that of healthy and diseased glomeruli, we demonstrate that kidney podocytes show marked stiffness sensitivity. Podocyte-specific markers that are critical in the formation of the renal filtration barrier are found to be regulated in association with stiffness-mediated cellular behaviors. While podocytes typically de-differentiate in culture and show diminished physiological function in nephropathies characterized by altered tissue stiffness, we show that gelatin-mTG substrates with Young’s modulus near that of healthy glomeruli elicit a pro-differentiation and maturation response in podocytes better than substrates either softer or stiffer. The pro-differentiation phenotype is characterized by upregulation of gene and protein expression associated with podocyte function, which is observed for podocytes cultured on gelatin-mTG gels of physiological stiffness independent of extracellular matrix coating type and density. Signaling pathways involved in stiffness-mediated podocyte behaviors are identified, revealing the interdependence of podocyte mechanotransduction and maintenance of their physiological function. This study also highlights the utility of the gelatin-mTG platform as anin vitrosystem with tunable stiffness over a range relevant for recapitulating mechanical properties of soft tissues, suggesting its potential impact on a wide range of research in cellular biophysics.
Molecular modeling and structural characterization of a high glycine–tyrosine hair keratin associated protein
Authors: Singh Rakesh S. , Palmer Jeremy C. , Pudney Paul D. A. , Paul Prem K. C. , Johannessen Christian , Debenedetti Pablo G. , Raut Janhavi , Lee Ken , Noro Massimo , Tiemessen David
Published: March 2017

For the first time, the molecular structure of a hair cortical matrix protein KAP8.1 has been characterised using modelling and spectroscopy.
Elucidation of charge-transfer SERS selection rules by considering the excited state properties and the role of electrode potential
Authors: Mohammadpour Mozhdeh , Khodabandeh Mohammad Hassan , Visscher Lucas , Jamshidi Zahra
Published: March 2017

The charge-transfer mechanism contributing to SERS is investigated by examining the properties of the excited CT-state and contributions of the electrode potential.
Polarity control of h-BN nanoribbon edges by strain and edge termination
Authors: Yamanaka Ayaka , Okada Susumu
Published: March 2017

We studied the polarity of h-BN nano-flakes in terms of their edge geometries, edge hydrogen termination, and uniaxial strain by evaluating their electrostatic potential using density functional theory.
High precision osmium stable isotope measurements by double spike MC-ICP-MS and N-TIMS
Authors: Nanne Josefine A. M. , Millet Marc-Alban , Burton Kevin W. , Dale Chris W. , Nowell Geoff M. , Williams Helen M.
Published: March 2017

We present a method for precise determination of stable osmium isotope compositions by MC-ICP-MS and N-TIMS using a double spike.
Synthesis and catalytic performance in the propene epoxidation of a vanadium catalyst supported on mesoporous silica obtained with the aid of sucrose
Authors: Janiszewska Ewa , Kowalak Stanislaw
Published: March 2017

Sucrose is an effective template for mesoporous silica—an efficient support of vanadium catalysts, active in propene epoxidation to propylene oxide.
Tuning diastereoisomerism in platinum(ii) phosphino- and aminothiolato hydrido complexes
Authors: Polo A. , Duran J. , Juanola R. , Real J. , Benet-Buchholz J. , Solà M. , Poater A.
Published: March 2017

Tuning between thecisandtransPt(ii) based complexes bearing phosphinothiolato and aminothiolato ligands.
Preparation and evaluation of the microwave absorption properties of template-free graphene foam-supported Ni nanoparticles
Authors: Xiong Liangliang , Yu Mei , Liu Jianhua , Li Songmei , Xue Bing
Published: March 2017

This study aims to explore superior microwave absorption properties using magnetic Ni nanoparticles to decorate a three-dimensional graphene foam.
Photoluminescence of self-assembled Ag(i) and Au(i) N-heterocyclic carbene complexes. Interplay the aurophilic, hydrogen bonding and hydrophobic interactions
Authors: Syu Herbert J. H. , Chiou Josh Y. Z. , Wang Ju-Chun , Lin Ivan J. B.
Published: March 2017

The incorporation of a 2-hydroxyl group at the long alkyl chain of NHC increases the hydrogen bonding interactions and thus induces the liquid crystal phase formation for the tetra nuclear Ag–NHC complex.
Electric field induced electronic properties modification of ZrS2/HfS2 van der Waals heterostructure
Authors: Shang Jimin , Zhang Shuai , Cheng Xuerui , Wei Zhongming , Li Jingbo
Published: March 2017

By using first-principles calculations, we investigate the electronic properties of a ZrS2/HfS2 heterostructure modulated by an external electric field.
Towards sustainable hydrocarbon fuels with biomass fast pyrolysis oil and electrocatalytic upgrading
Authors: Lam Chun Ho , Das Sabyasachi , Erickson Nichole C. , Hyzer Cale D. , Garedew Mahlet , Anderson James E. , Wallington Timothy J. , Tamor Michael A. , Jackson James E. , Saffron Christopher M.
Published: March 2017

Electrocatalytic hydrogenation offers a carbon and energy efficient strategy for upgrading pyrolytic bio-oil with renewable electricity in biomass processing depots.
New visible light excitable donor–acceptor 7-hydroxy-coumarins as blue fluorescent probes for selective staining of vacuoles in yeasts and L. donovani
Authors: Raghuvanshi Ashutosh , Kumar Jha Ajay , Kathuria Manoj , Priya Awasthi Bhanu , Purohit Deepak , Mitra Kalyan , Goel Atul
Published: March 2017

New 3-cyano-7-hydroxy-4-methylthio-coumarins (CHMCs) were discovered as blue fluorescent probes for staining vacuoles.
Supramolecular amphiphiles based on cyclodextrin and hydrophobic drugs
Authors: Sun Tao , Wang Qingbing , Bi Yunke , Chen Xinli , Liu Lisha , Ruan Chunhui , Zhao Zhifeng , Jiang Chen
Published: March 2017

Herein we report a novel “supra-prodrug-type” superamphiphile design: via a redox-sensitive self-immolative linker, a hydrophobic drug molecule was labeled with an azobenzene moiety, which was designed to be capped by a hydrophilic cyclodextrin (CD) molecule.
A simple functional carbon nanotube fiber for in vivo monitoring of NO in a rat brain following cerebral ischemia
Authors: Liu Li , Zhang Limin , Dai Zhihui , Tian Yang
Published: March 2017

A simple ratiometric electrochemical biosensor for NO monitoring in rat brain following cerebral ischemia was developed based on a carbon nanotube fiber modified with hemin.
Pore modulation of zirconium–organic frameworks for high-efficiency detection of trace proteins
Authors: Liu Chun-Sen , Zhang Zhi-Hong , Chen Min , Zhao Hui , Duan Feng-He , Chen Di-Ming , Wang Ming-Hua , Zhang Shuai , Du Miao
Published: March 2017

This work develops a series of tunable electrochemical aptasensors based on Zr-MOFs with modulated pores, showing promising potential for high-efficiency detection of trace proteins.
Dithiolato-bridged nickel–iron complexes as models for the active site of [NiFe]-hydrogenases
Authors: Song Li-Cheng , Yang Xi-Yue , Cao Meng , Gao Xiu-Yun , Liu Bei-Bei , Zhu Liang , Jiang Feng
Published: March 2017

While the first NiFe-based μ-hydroxo model [3]+ can be prepared by reaction of a dicarbonyl model [1]2+ with Me3NO·2H2O, the functional modeling of H2 activation catalyzed by the Ni-SIa state gives the t-hydride model [2]+ in high yield.
Bithienopyrroledione vs. thienopyrroledione based copolymers: dramatic increase of power conversion efficiency in bulk heterojunction solar cells
Authors: Qiao Xiaolan , Chen Weichao , Wu Qinghe , Zhang Shiqian , Wu Hongzhuo , Liu Zhiqiang , Yang Renqiang , Li Hongxiang
Published: March 2017

Bithienopyrroledione (bi-TPD) based polymers P1 and P2 are designed and synthesized.
A luminescent polyoxoniobate lanthanide derivative {Eu3(H2O)9[Nb48O138(H2O)6]}27−
Authors: Chen Shumin , Ma Pengtao , Luo Huihui , Wang Yangyang , Niu Jingyang , Wang Jingping
Published: March 2017

An Eu-containing polyoxoniobate (CN3H6)7K3H17{Eu3(H2O)9Nb48O138(H2O)6}·40H2O is obtained under the protection of citric acid, which is a triangular cylindrical entity and displays red emission.
Initiating radical reactions with non-thermal plasmas
Authors: Gorbanev Yury , Leifert Dirk , Studer Armido , O'Connell Deborah , Chechik Victor
Published: March 2017

Non-thermal plasmas initiate radical chain reactions under mild conditions without the need for any added initiators.
Enantioselective [2+2] annulation of simple aldehydes with isatin-derived ketimines via oxidative N-heterocyclic carbene catalysis
Authors: Xu Jianfeng , Yuan Shiru , Peng Jingyi , Miao Maozhong , Chen Zhengkai , Ren Hongjun
Published: March 2017

An unprecedented [2+2] annulation of aldehydes with ketimines to afford enantioenriched spirooxindole β-lactams via oxidative NHC catalysis is disclosed.
Visible-light-mediated C2-amination of thiophenes by using DDQ as an organophotocatalyst
Authors: Song Chunlan , Yi Hong , Dou Bowen , Li Yiying , Singh Atul K. , Lei Aiwen
Published: March 2017

A direct C–H amination of thiophenes was presented via an oxidation pathway under visible-light irradiation, in which the thiophene radical cation serves as the key intermediate. Various thiophenes and azoles could be transformed into the corresponding amination products well, and H2O was the only byproduct, which is environmentally benign.
Silver-promoted (radio)fluorination of unsaturated carbamates via a radical process
Authors: Yang Bin , Chansaenpak Kantapat , Wu Hongmiao , Zhu Lin , Wang Mengzhe , Li Zibo , Lu Hongjian
Published: March 2017

The intramolecular fluorocyclization of unsaturated carbamates proceeds via a cyclization/1,2-(hetero)aryl migration/fluorination cascade involving an unusual radical process, and provides a straightforward access to (radio)fluorinated oxazolidin-2-ones, oxazolidine-2,4-diones and 1,3-oxazinan-2-ones.
Capturing the multiscale dynamics of membrane protein complexes with all-atom, mixed-resolution, and coarse-grained models
Authors: Liao Chenyi , Zhao Xiaochuan , Liu Jiyuan , Schneebeli Severin T. , Shelley John C. , Li Jianing
Published: March 2017

Multiscale models reveal consistent structural stability as well as the swinging motion of an intracellular loop for a biological regulatory role.
Effects of Ge and Sn substitution on the metal–semiconductor transition and thermoelectric properties of Cu12Sb4S13tetrahedrite
Authors: Kosaka Yasufumi , Suekuni Koichiro , Hashikuni Katsuaki , Bouyrie Yohan , Ohta Michihiro , Takabatake Toshiro
Published: March 2017

The substitutions of Ge and Sn for Cu in Cu12Sb4S13tetrahedrite lead to the suppression of the metal–semiconductor transition and enhancement of the thermoelectric performance.
Time-resolved molecule counting by photon statistics across the visible spectrum
Authors: Grußmayer K. S. , Herten D.-P.
Published: March 2017

We have established a robust approach for estimating the number of independently emitting fluorophores from the photon statistics across the visible spectrum.
Detection and identification of Criegee intermediates from the ozonolysis of biogenic and anthropogenic VOCs: comparison between experimental measurements and theoretical calculations
Authors: Giorio Chiara , Campbell Steven J. , Bruschi Maurizio , Archibald Alexander T. , Kalberer Markus
Published: March 2017

Ozonolysis of alkenes is a key reaction in the atmosphere, playing an important role in determining the oxidising capacity of the atmosphere and acting as a source of compounds that can contribute to local photochemical “smog”. The reaction products of the initial step of alkene-ozonolysis are Criegee intermediates (CIs), which have for many decades eluded direct experimental detection because of their very short lifetime. We use an innovative experimental technique, stabilisation of CIs with spin traps and analysis with proton transfer reaction mass spectrometry, to measure the gas phase concentration of a series of CIs formed from the ozonolysis of a range of both biogenic and anthropogenic alkenes in flow tube experiments. Density functional theory (DFT) calculations were used to assess the stability of the CI-spin trap adducts and show that the reaction of the investigated CIs with the spin trap occurs very rapidly except for the large β-pinene CI. Our measurement method was used successfully to measure all the expected CIs, emphasising that this new technique is applicable to a wide range of CIs with different molecular structures that were previously unidentified experimentally. In addition, for the first time it was possible to study CIs simultaneously in an even more complex reaction system consisting of more than one olefinic precursor. Comparison between our new experimental measurements, calculations of stability of the CI-spin trap adducts and results from numerical modelling, using the master chemical mechanism (MCM), shows that our new method can be used for the quantification of CIs produced in situ in laboratory experiments.
The lab-on-PCB approach: tackling the μTAS commercial upscaling bottleneck
Authors: Moschou Despina , Tserepi Angeliki
Published: March 2017

Recent developments in the lab-on-PCB integration technology, highlighting its standardized industrial fabrication potential.
Conventional Type II photoinitiators as activators for photoinduced metal-free atom transfer radical polymerization
Authors: Allushi Andrit , Kutahya Ceren , Aydogan Cansu , Kreutzer Johannes , Yilmaz Gorkem , Yagci Yusuf
Published: March 2017

A novel methodology for photoinduced metal-free Atom Transfer Radical Polymerization (ATRP) by using conventional Type II photoinitiators such as benzophenone, thioxanthone, isopropyl thioxanthone and camphorquinone as sensitizers is presented.
Fine-tuning the magnetocaloric effect and SMMs behaviors of coplanar RE4 complexes by β-diketonate coligands
Authors: Gao Hong-Ling , Wang Ni-Ni , Wang Wen-Min , Shen Hai-Yun , Zhou Xiao-Pu , Chang Yi-Xin , Zhang Ru-Xia , Cui Jian-Zhong
Published: March 2017

By introducing different β-diketonate coligands, Gd4 complexes show cryogenic magnetic refrigeration properties, whereas Dy4 clusters exhibit different SMMs behaviors.
Photocatalytically active TiO2 microtubes assembled with radially aligned nanowires
Authors: Xu Yang , Wen Wei , Tang Ming-Zao , Wu Jin-Ming
Published: March 2017

A PET-templated route is developed to synthesize highly photocatalytically active TiO2 microtubes assembled with radially aligned nanowires.
CO2 separation membranes with high permeability and CO2/N2 selectivity prepared by electrostatic self-assembly of polyethylenimine on reverse osmosis membranes
Authors: Sun Jing , Yi Zhuan , Zhao Xueting , Zhou Yong , Gao Congjie
Published: March 2017

A facilitated transport membrane with high CO2 permeance and CO2/N2 selectivity was prepared by an aqueous self-assembly method using commercially available PEI and RO membranes as the assembled molecule and substrate, respectively.
Metal-free C–H alkylation of heteroarenes with alkyltrifluoroborates: a general protocol for 1°, 2° and 3° alkylation
Authors: Matsui Jennifer K. , Primer David N. , Molander Gary A.
Published: March 2017

A photoredox-catalyzed C–H functionalization of heteroarenes using a variety of primary, secondary, and tertiary alkyltrifluoroborates is reported.
Transforming waste newspapers into nitrogen-doped conducting interlayers for advanced Li–S batteries
Authors: Chang Chi-Hao , Chung Sheng-Heng , Manthiram Arumugam
Published: March 2017

A nitrogen-doped conducting (NC) interlayer derived from waste newspapers exhibits a synergistic polysulfide-trapping capability due to abundant microporous structures and nitrogen-doped sites. Li–S cells employing NC interlayers demonstrate improved electrochemical utilization and cell reversibility.
A facile and scalable fabrication method for thin film composite reverse osmosis membranes: dual-layer slot coating
Authors: Park Sung-Joon , Ahn Won-Gi , Choi Wansuk , Park Sang-Hee , Lee Jong Suk , Jung Hyun Wook , Lee Jung-Hyun
Published: March 2017

The dual-layer slot coating technique can fabricate a sub-10 nm ultrathin, highly selective membrane outperforming commercial reverse osmosis membranes.
Correction: Nanoporous film-mediated growth of ultrathin and continuous metal–organic framework membranes for high-performance hydrogen separation
Authors: Zhang Shenxiang , Wang Zhenggong , Ren Huiting , Zhang Feng , Jin Jian
Published: March 2017

Correction for ‘Nanoporous film-mediated growth of ultrathin and continuous metal–organic framework membranes for high-performance hydrogen separation’ by Shenxiang Zhang et al., J. Mater. Chem. A, 2017, 5, 1962–1966.
Use of Models of Finite Elements in the Biomechanics of the Lumbar Spine
Authors: Oppermann Marcelo , Brasil Lourdes Mattos , Silva Alex Sandro Araújo , Cardoso Leandro Xavier
Published: March 2017

The same correspondence between general mechanics and civil engineering is true for biomechanics and surgical implants. Currently, numerous mechanical processes are required until a prosthesis is offered to its target audience. These processes typically require human or animal vertebrae, as well as all the complexity involving such tissues, for example, an ethics committee, the availability of materials, etc. Thus, finite element models (FEMs) have become a great option to carry out biomechanical tests independently from anatomical specimens, and, at the same time, to obtain mathematical data to assist in the general physical understanding. The present review discusses the mechanical principles involved in bioengineering, clarifies the steps for the development of FEMs, and shows application scenarios for these models. To the knowledge of the authors, the present paper is the first review study in Portuguese aimed to health care professionals in a language accessible to them.
Risk Assessment Scores for Cancer-Associated Venous Thromboembolic Disease
Authors: Angelini Dana , Khorana Alok
Published: March 2017

Current guidelines recommend that patients with cancer be assessed for venous thromboembolism (VTE) risk at the time of chemotherapy initiation and periodically thereafter. Rates of VTE vary substantially among cancer patients. Multiple clinical factors contribute to VTE risk, including the primary site of cancer, extent of disease, interventions including major surgery, hospitalization, and systemic therapy. However, risk of VTE cannot reliably be predicted based on a single risk factor or biomarker. Within the last decade, risk assessment scores have been developed in cancer patients to more reliably predict thromboembolic events. This review provides an overview of evidence supporting the use of such tools for both primary and recurrent cancer-associated VTE. Potential applications of risk assessment tools as well as current knowledge gaps are outlined.
Grisel Syndrome: Case Report
Authors: Roncaglio Bruno , Debom Tadeu Gervazoni , Brazolino Marcus Alexandre Novo , Maia Thiago Cardoso , Batista Filho José Lucas , Cardoso Igor Machado , Jacob Junior Charbel
Published: March 2017

We report a case of a rare disease, Grisel syndrome, which manifests as a kind of rotational fixation of the atlas on the axis, resulting from an infectious process of the upper airways. In the present report, we discuss etiology, clinical presentation, diagnosis, treatment and outcome after intervention.
First clinical experiences with a novel endoscopic over-the-scope clip system
Authors: Dinelli Marco , Omazzi Barbara , Andreozzi Paolo , Zucchini Nicola , Redaelli Alessandro , Manes Gianpiero
Published: March 2017

We describe our experience with a new over-the-scope clip (OTSC) system (Padlock Clip™) in the treatment of 14 patients. Eight of the 14 patients were treated for closure of gastrointestinal fistulas (n = 4), iatrogenic gastrointestinal perforations (n = 2), or hemostasis of post-polypectomy bleeding (n = 2). The site of clipping was the lower gastrointestinal tract in five patients and the upper gastrointestinal tract in three patients. The clip was successfully delivered in seven out of the eight patients and clinical success was achieved in all patients. Endoscopic full thickness resection (EFTR) was performed to treat six patients: four with recurrent adenoma (n = 4), one with ulcerated nodules at ileorectal anastomosis, and one with a neuro-endocrine tumor of the rectum. A complete intestinal wall resection was achieved in three of the six patients (50 %) and an R0 resection in five of the six patients (83.3 %). No complications related to the procedure and no recurrence at endoscopic follow-up were observed in any patient. The novel Padlock Clip seems to be an effective and safe tool to treat gastrointestinal fistulas, perforations or post-polypectomy bleeding, and to perform EFTR.
An electromagnetic method for removing the communication blackout with a space vehicle upon re-entry into the atmosphere
Authors: Cheng Jianjun , Jin Ke , Kou Yong , Hu Ruifeng , Zheng Xiaojing
Published: March 2017

When a hypersonic vehicle travels in the Earth and Mars atmosphere, the surface of the vehicle is surrounded by a plasma layer, which is an envelope of ionized air, created from the compression and heat of the atmosphere by the shock wave. The vehicles will lose contact with ground stations known as the reentry communication blackout. Based on the magnetohydrodynamic framework and electromagnetic wave propagation theory, an analytical model is proposed to describe the effect of the effectiveness of electromagnetic mitigation scheme on removing the reentry communication blackout. C and Global Positioning System (GPS) bands, two commonly used radio bands for communication, are taken as the cases to discuss the effectiveness of the electromagnetic field mitigation scheme. The results show that the electron density near the antenna of vehicles can be reduced by the electromagnetic field, and the required external magnetic field strength is far below the one in the magnetic window method. The directions of the external electric field and magnetic field have a significant impact on the effectiveness of the mitigation scheme. Furthermore, the effect of electron collisions on the required applied electromagnetic field is discussed, and the result indicates that electron collisions are a key factor to analyze the electromagnetic mitigation scheme. Finally, the feasible regions of the applied electromagnetic field for eliminating blackout are given. These investigations could have a significant benefit on the design and optimization of electromagnetic mitigation scheme for the blackout problem.
Depth-resolved local conformation and thermal relaxation of polystyrene near substrate interface
Authors: Nguyen Hung Kim , Inutsuka Manabu , Kawaguchi Daisuke , Tanaka Keiji
Published: March 2017

By means of sum-frequency generation spectroscopy, we report a depth-resolved measurement of the local conformation and chain relaxation of polystyrene (hPS) located at different distances from the quartz interface. To control the distance from the quartz interface, deuterated polystyrene (dPS) layers with thicknesses of 3.4, 7.5, and 20 nm were coated on the quartz substrates. The hPS chains in direct contact with the substrate surface predominantly orient their phenyl rings in a direction normal to the substrate. This conformation was found to be barely relaxed when the film was annealed for 24 h at 423 K, higher than the bulk glass transition temperature. In contrast, for the hPS chains supported on the dPS layer, the orientation of phenyl rings of hPS became weaker with the annealing and this trend was more significant with increasing distance from the quartz substrate. In particular, the orientation of phenyl rings of hPS after annealing vanished at a distance of 20 nm. These results might provide an important evidence of the difference in the relaxation dynamics of the PS chains located at different distances from the quartz interface.
Reversible self-propelled Leidenfrost droplets on ratchet surfaces
Authors: Jia Zhi-hai , Chen Meng-yao , Zhu Hai-tao
Published: March 2017

We investigate the self-propelled motion of the Leidenfrost droplets on hot surfaces with ratchet like topology. It is found that on hot ratchet surfaces with the certain geometry parameters, the droplets move in the direction towards the steep side of the teeth; as the surface temperature rises, droplets are observed to self propel to the right-angle side direction. Furthermore, there exists a temperature threshold to trigger the motion, at which the droplets do not move in either direction but stay at the stagnation state. A physical model is proposed to analyze the observation in this paper.
A no-go theorem for the n-twistor description of a massive particle
Authors: Okano Satoshi , Deguchi Shinichi
Published: March 2017

It is proved that the n-twistor expression of a particle’s four-momentum vector reduces, by a unitary transformation, to the two-twistor expression for a massive particle or the one-twistor expression for a massless particle. Therefore the genuine n-twistor description of a massive particle in four-dimensional Minkowski space fails for the case n≥3.
Investigating the origins of high multilevel resistive switching in forming free Ti/TiO2−x-based memory devices through experiments and simulations
Authors: Bousoulas P. , Giannopoulos I. , Asenov P. , Karageorgiou I. , Tsoukalas D.
Published: March 2017

Although multilevel capability is probably the most important property of resistive random access memory (RRAM) technology, it is vulnerable to reliability issues due to the stochastic nature of conducting filament (CF) creation. As a result, the various resistance states cannot be clearly distinguished, which leads to memory capacity failure. In this work, due to the gradual resistance switching pattern of TiO2−x-based RRAM devices, we demonstrate at least six resistance states with distinct memory margin and promising temporal variability. It is shown that the formation of small CFs with high density of oxygen vacancies enhances the uniformity of the switching characteristics in spite of the random nature of the switching effect. Insight into the origin of the gradual resistance modulation mechanisms is gained by the application of a trap-assisted-tunneling model together with numerical simulations of the filament formation physical processes.
Transport properties of the binary mixtures of the three organic liquids toluene, methanol, and cyclohexane
Authors: Lapeira E. , Gebhardt M. , Triller T. , Mialdun A. , Köhler W. , Shevtsova V. , Bou-Ali M. M.
Published: March 2017

We report on the measurements of diffusion (D), thermodiffusion (DT), and Soret (ST) coefficients in binary pairs of the ternary system toluene-methanol-cyclohexane using different instrumental techniques: microgravity measurements (SODI/DCMIX2) on the International Space Station, thermogravitational column in combination with sliding symmetric tubes, optical beam deflection, optical digital interferometry, and counter flow cell. The binary systems have large regions where the mixtures are either not miscible or the Soret coefficient is negative. All the coefficients have been measured over a wide composition range with the exception of a miscibility gap. Results from different instruments and literature data are in favorable agreement over a broad composition range. Additionally, we have carefully measured the physical properties and the optical contrast factors (∂n/∂c)p,T and (∂n/∂T)p,c. The latter ones were also calculated using the Looyenga equation. The measurements in methanol-cyclohexane mixture revealed a decay of the diffusion coefficient when approaching the miscibility gap. We have interpreted this in the spirit of the pseudospinodal concept.
Development and experimental study of oil-free capacitor module for plasma focus device
Authors: Sharma Ravindra Kumar , Sharma Archana
Published: March 2017

This development is concerned with the compact capacitor module for a plasma focus device. Oil-free, non-standard geometry capacitors are designed and developed for high current delivery in sub-microseconds time. Metalized dielectric film based pulse capacitor becomes progressively less viable at currents above 10 kA. It is due to reliability and energy scaling difficulties, based on effects such as vaporization, high resistivity, and end connection. Bipolar electrolytic capacitors are also not preferred due to their limited life and comparatively low peak current delivery. Bi-axially oriented polypropylene (BOPP) film with extended aluminum foil is a combination to deliver moderately high power. But, electrically weak points, relative permittivity, and the edge gap margins have made its adoption difficult. A concept has been developed in lab for implementing the above combination in a less complex and costly manner. This paper concerns the development and testing process techniques for quite different hollow cylindrical, oil-free capacitors (4 μF, 10 kV, 20 nH). Shot life of 1000 has been experimentally performed on the test bed at its rated energy density level. The technological methods and engineering techniques are now available and utilized for manufacturing and testing of BOPP film based oil-free capacitors.
Electrical transport measurements of thin film samples under high hydrostatic pressure
Authors: Zabaleta J. , Parks S. C. , Baum B. , Teker A. , Syassen K. , Mannhart J.
Published: March 2017

We present a method to perform electrical measurements of epitaxial films and heterostructures a few nanometers thick under high hydrostatic pressures in a diamond anvil cell (DAC). Hydrostatic pressure offers the possibility to tune the rich landscape of properties shown by epitaxial heterostructures, systems in which the combination of different materials, performed with atomic precision, can give rise to properties not present in their individual constituents. Measuring electrical conductivity under hydrostatic pressure in these systems requires a robust method that can address all the challenges: the preparation of the sample with side length and thickness that fits in the DAC setup, a contacting method compatible with liquid media, a gasket insulation that resists high forces, as well as an accurate procedure to place the sample in the pressure chamber. We prove the robustness of the method described by measuring the resistance of a two dimensional electron system buried at the interface between two insulating oxides under hydrostatic conditions up to ∼5 GPa. The setup remains intact until ∼10 GPa, where large pressure gradients affect the two dimensional conductivity.
Forced oscillations dynamic tribometer with real-time insights of lubricated interfaces
Authors: Yahiaoui M. , Rigaud E. , Mazuyer D. , Cayer-Barrioz J.
Published: March 2017

This paper presents an innovative forced oscillations dynamic tribometer, the CHRONOS tribometer, with a lubricated ball-on-flat contact configuration fitted out with an in situ optical visualization system and a triggered high-speed camera. The CHRONOS tribometer generates controlled oscillating kinematics by means of a shaker with a range of strokes from 5 μm to 2.5 mm and an oscillation frequency which can be adjusted from 5 Hz to 250 Hz. Displacement and velocity are measured using a vibrometer. The ball-on-flat mean contact pressure is set between 200 MPa and 600 MPa. During motion, the instantaneous normal and friction forces and the interfacial film thickness distribution (in the nanometer scale) are simultaneously measured. In addition to this instantaneous approach, a more macroscopic approach is developed in terms of moving averages of friction and velocity. Another parameter, the friction-velocity tilt angle, is also introduced. This last parameter may give information on the friction-velocity dependence. Eventually, the experiments performed on the CHRONOS device lead to the representation of synchronized temporal signals of displacement/velocity, friction, and lubricant central film thickness. This superimposition of key parameters reveals time effects introduced by the periodical fluid squeeze and flow in the contact.
A global plasma model for reactive deposition of compound films by modulated pulsed power magnetron sputtering discharges
Authors: Zheng B. C. , Wu Z. L. , Wu B. , Li Y. G. , Lei M. K.
Published: March 2017

A spatially averaged, time-dependent global plasma model has been developed to describe the reactive deposition of a TiAlSiN thin film by modulated pulsed power magnetron sputtering (MPPMS) discharges in Ar/N2 mixture gas, based on the particle balance and the energy balance in the ionization region, and considering the formation and erosion of the compound at the target surface. The modeling results show that, with increasing the N2 partial pressure from 0% to 40% at a constant working pressure of 0.3 Pa, the electron temperature during the strongly ionized period increases from 4 to 7 eV and the effective power transfer coefficient, which represents the power fraction that effectively heats the electrons and maintains the discharge, increases from about 4% to 7%; with increasing the working pressure from 0.1 to 0.7 Pa at a constant N2 partial pressure of 25%, the electron temperature decreases from 10 to 4 eV and the effective power transfer coefficient decreases from 8% to 5%. Using the modeled plasma parameters to evaluate the kinetic energy of arriving ions, the ion-to-neutral flux ratio of deposited species, and the substrate heating, the variations of process parameters that increase these values lead to an enhanced adatom mobility at the target surface and an increased input energy to the substrate, corresponding to the experimental observation of surface roughness reduction, the microstructure transition from the columnar structure to the dense featureless structure, and the enhancement of phase separation. At higher N2 partial pressure or lower working pressure, the modeling results demonstrate an increase in electron temperature, which shifts the discharge balance of Ti species from Ti+ to Ti2+ and results in a higher return fraction of Ti species, corresponding to the higher Al/Ti ratio of deposited films at these conditions. The modeling results are well correlated with the experimental observation of the composition variation and the microstructure transition of deposited TiAlSiN compound films, demonstrating the applicability of this approach in understanding the characteristics of reactive MPPMS discharges as well as the composition and microstructure of deposited compound films. The model for reactive MPPMS discharges has no special limitations and is applicable to high power impulse magnetron sputtering discharges as well.
Beyond histograms: Efficiently estimating radial distribution functions via spectral Monte Carlo
Authors: Patrone Paul N. , Rosch Thomas W.
Published: March 2017

Despite more than 40 years of research in condensed-matter physics, state-of-the-art approaches for simulating the radial distribution function (RDF) g(r) still rely on binning pair-separations into a histogram. Such methods suffer from undesirable properties, including subjectivity, high uncertainty, and slow rates of convergence. Moreover, such problems go undetected by the metrics often used to assess RDFs. To address these issues, we propose (I) a spectral Monte Carlo (SMC) quadrature method that yields g(r) as an analytical series expansion and (II) a Sobolev norm that assesses the quality of RDFs by quantifying their fluctuations. Using the latter, we show that, relative to histogram-based approaches, SMC reduces by orders of magnitude both the noise in g(r) and the number of pair separations needed for acceptable convergence. Moreover, SMC reduces subjectivity and yields simple, differentiable formulas for the RDF, which are useful for tasks such as coarse-grained force-field calibration via iterative Boltzmann inversion.