Photo-physical and structural interactions between viologen phosphorus-based dendrimers and human serum albumin

International Nuclear Information System (INIS)

Ciepluch, Karol; Katir, Nadia; El Kadib, Abdelkrim; Weber, Monika; Caminade, Anne-Marie; Bousmina, Mostapha; Pierre Majoral, Jean; Bryszewska, Maria

2012-01-01

This work deals with photo-physical and structural interactions between viologen phosphorus dendrimers and human serum albumin (HSA). Viologens are derivatives of 4,4′-bipyridinium salts. Aiming to rationalize the parameters governing such interactions eight types of these polycationic dendrimers in which the generation, the number of charges, the nature of the core and of the terminal groups vary from one to another, were designed and used. The influence of viologen-based dendrimers' on human serum albumin has been investigated. The photo-physical interactions of the two systems have been monitored by fluorescence quenching of free L-tryptophan and of HSA tryptophan residue. Additionally, using circular dichroism (CD) the effect of dendrimers on the secondary structure of albumin was measured. The obtained results show that viologen dendrimers interact with human serum albumin quenching its fluorescence either by collisional (dynamic) way or by forming complexes in a ground state (static quenching). In some cases the quenching is accompanied by changes of the secondary structure of HSA. - Highlights: ► Photo-physical interactions between viologen phosphorus dendrimers and human serum albumin (HSA) were investigated. ► The viologen dendrimers can quench the fluorescence of tryptophan in HSA. ► CD spectra to explain the changes in secondary structure of albumin after exposition of dendrimers.

Photoinduced Charge Shifts and Electron Transfer in Viologen-Tetraphenylborate Complexes: Push-Pull Character of the Exciplex.

Science.gov (United States)

Santos, Willy G; Budkina, Darya S; Deflon, Victor M; Tarnovsky, Alexander N; Cardoso, Daniel R; Forbes, Malcolm D E

2017-06-14

Viologen-tetraarylborate ion-pair complexes were prepared and investigated by steady-state and time-resolved spectroscopic techniques such as fluorescence and femtosecond transient absorption. The results highlight a charge transfer transition that leads to changes in the viologen structure in the excited singlet state. Femtosecond transient absorption reveals the formation of excited-state absorption and stimulated emission bands assigned to the planar (k obs < 10 12 s -1 ) and twisted (k obs ∼ 10 10 s -1 ) structures between two pyridinium groups in the viologen ion. An efficient photoinduced electron transfer from the tetraphenylborate anionic moiety to the viologen dication was observed less than 1 μs after excitation. This is a consequence of the push-pull character of the electron donor twisted viologen structure, which helps formation of the borate triplet state. The borate triplet state is deactivated further via a second electron transfer process, generating viologen cation radical (V •+ ).

Photo-physical and structural interactions between viologen phosphorus-based dendrimers and human serum albumin

Energy Technology Data Exchange (ETDEWEB)

Ciepluch, Karol, E-mail: ciepluch@biol.uni.lodz.pl [Department of General Biophysics, University of Lodz, 141/143 Pomorska St., 90-236 Lodz (Poland); Katir, Nadia [Laboratoire de Chimie de Coordination du CNRS (LCC), 205 route de Narbonne, F-31077 Toulouse cedex 4 (France); Institute of Nanomaterials and Nanotechnology (INANOTECH)-MAScIR (Moroccan Foundation for Advanced Science, Innovation and Research), ENSET, Avenue de l' Armee Royale, Madinat El Irfane, 10100 Rabat (Morocco); El Kadib, Abdelkrim [Institute of Nanomaterials and Nanotechnology (INANOTECH)-MAScIR (Moroccan Foundation for Advanced Science, Innovation and Research), ENSET, Avenue de l' Armee Royale, Madinat El Irfane, 10100 Rabat (Morocco); Weber, Monika [Department of General Biophysics, University of Lodz, 141/143 Pomorska St., 90-236 Lodz (Poland); Caminade, Anne-Marie [Laboratoire de Chimie de Coordination du CNRS (LCC), 205 route de Narbonne, F-31077 Toulouse cedex 4 (France); Bousmina, Mostapha [Hassan II Academy of Sciences and Technology, Avenue MVI, Km4, 10220 Rabat (Morocco); Pierre Majoral, Jean [Laboratoire de Chimie de Coordination du CNRS (LCC), 205 route de Narbonne, F-31077 Toulouse cedex 4 (France); Hassan II Academy of Sciences and Technology, Avenue MVI, Km4, 10220 Rabat (Morocco); Bryszewska, Maria [Department of General Biophysics, University of Lodz, 141/143 Pomorska St., 90-236 Lodz (Poland)

2012-06-15

This work deals with photo-physical and structural interactions between viologen phosphorus dendrimers and human serum albumin (HSA). Viologens are derivatives of 4,4 Prime -bipyridinium salts. Aiming to rationalize the parameters governing such interactions eight types of these polycationic dendrimers in which the generation, the number of charges, the nature of the core and of the terminal groups vary from one to another, were designed and used. The influence of viologen-based dendrimers' on human serum albumin has been investigated. The photo-physical interactions of the two systems have been monitored by fluorescence quenching of free L-tryptophan and of HSA tryptophan residue. Additionally, using circular dichroism (CD) the effect of dendrimers on the secondary structure of albumin was measured. The obtained results show that viologen dendrimers interact with human serum albumin quenching its fluorescence either by collisional (dynamic) way or by forming complexes in a ground state (static quenching). In some cases the quenching is accompanied by changes of the secondary structure of HSA. - Highlights: Black-Right-Pointing-Pointer Photo-physical interactions between viologen phosphorus dendrimers and human serum albumin (HSA) were investigated. Black-Right-Pointing-Pointer The viologen dendrimers can quench the fluorescence of tryptophan in HSA. Black-Right-Pointing-Pointer CD spectra to explain the changes in secondary structure of albumin after exposition of dendrimers.

Reversible polycolour change of viologens from violet through transparent to white

International Nuclear Information System (INIS)

Hoshino, Katsuyoshi; Oikawa, Yosuke; Sakabe, Ichiro; Komatsu, Toshiki

2009-01-01

The electrochromic properties of 1,1'-dibenzyl-4,4'-bipyridinium and 1,1'-diheptyl-4,4'-bipyridinium were investigated in the presence of MBr (M = Li + , Na + , and K + ). The cyclic voltammograms of these viologens showed a white-coloured state in addition to the usual violet one-electron reduction state and the colourless divalent state. Chemical analyses (FT-IR and XPS spectra) of the white film and some control experiments with different supporting electrolytes, MX (X = Cl - and I - ), revealed that the viologens formed water-insoluble ion pairs with tribromide generated by the electrooxidation of monobromide to produce a white film. The film was reversibly decolourized electrochemically to the initial transparent state, providing the polyelectrochromism using the simple viologen/MBr systems. The colouration efficiencies for the violet and the white-coloured states were 170 cm 2 /C and 104 cm 2 /C, respectively.

Porphyrinic supramolecular daisy chains incorporating pillar[5]arene-viologen host-guest interactions

KAUST Repository

Fathalla, Maher; Strutt, Nathan; Srinivasan, Sampath; Katsiev, Khabiboulakh; Hartlieb, Karel J.; Bakr, Osman; Stoddart, J. Fraser

2015-01-01

A porphyrin functionalised with pillar[5]arene and a viologen at its 5- and 15-meso positions assembles in a head-to-tail manner, producing linear supramolecular daisy chains in dichloromethane. At high concentrations, it forms an organogel which has been investigated by electron microscopy and rheological measurements, paving the way for the preparation of other functional supramolecular assemblies which harness viologen"⊂" pillararene host-guest interactions.

Porphyrinic supramolecular daisy chains incorporating pillar[5]arene-viologen host-guest interactions

KAUST Repository

Fathalla, Maher

2015-05-18

A porphyrin functionalised with pillar[5]arene and a viologen at its 5- and 15-meso positions assembles in a head-to-tail manner, producing linear supramolecular daisy chains in dichloromethane. At high concentrations, it forms an organogel which has been investigated by electron microscopy and rheological measurements, paving the way for the preparation of other functional supramolecular assemblies which harness viologen"⊂" pillararene host-guest interactions.

A high sensitive ion pairing probe (the interaction of pyrenetetrasulphonate and methyl viologen): Salt and temperature dependences and applications

Energy Technology Data Exchange (ETDEWEB)

Santana, Jeferson [Departamento de Bioquímica e Departamento de Química, Instituto de Química, Universidade de São Paulo, SP (Brazil); Perez, Katia R. [Departamento de Biofísica, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo-SP (Brazil); Pisco, Thiago B.; Pavanelli, David D.; Briotto Filho, Décio; Rezende, Daisy [Departamento de Bioquímica e Departamento de Química, Instituto de Química, Universidade de São Paulo, SP (Brazil); Rezende Triboni, Eduardo [Universidade Nove de Julho, São Paulo, São Paulo-SP (Brazil); Chagas Alves Lima, Francisco das [Coordenação de Química, Universidade Estadual do Piauí, Teresina-PI (Brazil); Lopes Magalhães, Janildo [Departamento de Química, Centro de Ciências da Natureza, Universidade Federal do Piauí, Centro de Ciências da Natureza, Teresina, PI (Brazil); Midea Cuccovia, Iolanda [Departamento de Bioquímica e Departamento de Química, Instituto de Química, Universidade de São Paulo, SP (Brazil); and others

2014-07-01

The interaction between pyrenetetrasulphonate (PTS) and methyl viologen (MV{sup 2+}) leads to a 1:1 charge transfer complex (CTC) in the concentration range below mmol L{sup −1} of the ligands. Quantum mechanical calculations show the 1:1 complex having the planar moiety of PTS and the charges of the sulfonate groups stabilized by the twisted rings of the positively charged MV{sup 2+} species. The peculiar nature of PTS includes high fluorescence quantum yield (∼1), clear specular UV–vis spectra and fluorescence emission images, as well similar S{sub 2}←S{sub 0} and S{sub 3}←S{sub 0} transitions as those of S{sub 1}←S{sub 0,} all of them exhibiting well resolved vibrational structure. MV{sup 2+} has well known electron-accepting properties that favor the complexation. These features were studied as a function of salt concentration and temperature dependences allowing a detailed comprehension of static and dynamic association processes. Quantum mechanical calculations show the 1:1 stabilization of PTS/MV{sup 2+}. In addition the effect of urea on the CTC equilibrium is presented, as expected the additive acts towards the non-complexed species (solvated free ions). The fluorescence quenching of MV{sup 2+}over PTS highlights is one of the applications of this effect for giant vesicles characterization. - Highlights: • We determined the details of PTS/MV{sup 2+} 1:1 complex formation. • Ground and excited states formation is operative. • Ion pairing effects due to urea effect are shown. • Vesicle formation is illustrated by the pair.

A new repeatable, optical writing and electrical erasing device based on photochromism and electrochromism of viologen

International Nuclear Information System (INIS)

Gao, Li-ping; Wei, Jian; Wang, Yue-chuan; Ding, Guo-jing; Yang, Yu-lin

2012-01-01

New optical writing and electrical erasing devices have been successfully fabricated that exploit the photochromism and electrochromism of viologen. In a preliminary study, both the structures of viologen and device were investigated in detail by UV–vis spectra in order to confirm their effects on the optical writing and electrical erasing performances of corresponding devices. For sandwiched, single and complementary devices based on benzyl viologen (BV 2+ ), only optical writing can be performed, not electrical erasing operations, which indicated these devices cannot realize optical information rewriting. For single and complementary devices based on styrene-functional viologen (V BV 2+ ) and acrylic-functional viologen (ACV 2+ ), optical writing and electrical erasing operations can be reversibly performed and optical information rewriting realized. It is clear that single devices based on V BV 2+ and ACV 2+ possess better performance accompanied with contrast without significant degradation and bleaching times and without significant deterioration over 10 repeated writing/erasing cycles. Furthermore, we put forward possible mechanisms for sandwiched, single and complementary devices based on V BV 2+ and ACV 2+ for the optical writing and electrical erasing operations. This study provides a new strategy to design optical writing and electrical erasing devices to realize optical information rewriting. (paper)

A high constitutive catalase activity confers resistance to methyl viologen-promoted oxidative stress in a mutant of the cyanobacterium Nostoc punctiforme ATCC 29133.

Science.gov (United States)

Moirangthem, Lakshmipyari Devi; Bhattacharya, Sudeshna; Stensjö, Karin; Lindblad, Peter; Bhattacharya, Jyotirmoy

2014-04-01

A spontaneous methyl viologen (MV)-resistant mutant of the nitrogen-fixing cyanobacterium Nostoc punctiforme ATCC 29133 was isolated and the major enzymatic antioxidants involved in combating MV-induced oxidative stress were evaluated. The mutant displayed a high constitutive catalase activity as a consequence of which, the intracellular level of reactive oxygen species in the mutant was lower than the wild type (N. punctiforme) in the presence of MV. The superoxide dismutase (SOD) activity that consisted of a SodA (manganese-SOD) and a SodB (iron-SOD) was not suppressed in the mutant following MV treatment. The mutant was, however, characterised by a lower peroxidase activity compared with its wild type, and its improved tolerance to externally added H₂O₂ could only be attributed to enhanced catalase activity. Furthermore, MV-induced toxic effects on the wild type such as (1) loss of photosynthetic performance assessed as maximal quantum yield of photosystem II, (2) nitrogenase inactivation, and (3) filament fragmentation and cell lysis were not observed in the mutant. These findings highlight the importance of catalase in preventing MV-promoted oxidative damage and cell death in the cyanobacterium N. punctiforme. Such oxidative stress resistant mutants of cyanobacteria are likely to be a better source of biofertilisers, as they can grow and fix nitrogen in an unhindered manner in agricultural fields that are often contaminated with the herbicide MV, also commonly known as paraquat.

Turn-on fluorescence probes based on pyranine/viologen charge-transfer complexes for the determination of nucleotides

Energy Technology Data Exchange (ETDEWEB)

Schäferling, Michael, E-mail: Michael.schaeferling@utu.fi; Lang, Thomas; Schnettelker, Annette

2014-10-15

The formation of ground state charge-transfer complexes between pyranine (8-hydroxypyrene-1,3,6-trisulfonic acid) and viologen (paraquat) derivatives is utilized for the design of novel fluoroionophores for the determination of phosphate species, particularly of nucleotides. The strong quenching of the pyranine fluorescence by viologen-type charge transfer acceptors can be countermanded if these are functionalized with triethylammonium groups that serve as recognition elements for phosphate anions. We report on the fluorogenic responses of these water-soluble molecular probes in presence of different phosphates. Absorbance measurements give additional information on the charge transfer complex formation and the interaction with nucleotides. The experimental data show that these aggregates form attractive, simple and versatile fluorescence turn-on probes for nucleoside triphosphates. The reversibility of the fluorescence response is demonstrated by means of an enzymatic model assay using ATPase for the decomposition of adenosine triphosphate. - Highlights: • Pyranine/viologen charge-transfer complexes as molecular probe for ATP recognition. • Fluorescence turn on mechanism. • Selective compared to other nucleotides and phosphate anions. • Fast and reversible response applicable to monitor enzymatic reactions.

Fabrication, electrochemical and catalytic properties of the nanocomposites composed of phosphomolybdic acid and viologen-functionalized multi-walled carbon nanotubes

Science.gov (United States)

Liu, Jiang; Wang, Jing; Chen, Meng; Qian, Dong-Jin

2017-08-01

Electroactive nanocomposites composed of phosphomolybdic acid (PMA) and viologen-functionalized carbon nanotubes were synthesized and used as heterogeneous catalysts for the electrocatalytic reduction of bromate. Viologen (V) was first covalently anchored on the surface of multi-walled carbon nanotubes (MWNTs) to produce positively charged MWNT-V polyelectrolyte, which was then combined with PMA through electrostatic interaction to form MWNT-V@PMA nanocomposites. Thermogravimetric analysis revealed that the organic species in the MWNT-V polyelectrolyte was about 30% in weight. Composition, structure, and morphology of the nanocomposites were investigated by using UV-vis, infrared, Raman and X-ray photoelectron spectroscopy as well as field emission transition electron microscope. The thickness of organic substituents, viologen, and PMA in the nanocomposites was approximately 10 nm covered on the surface of MWNTs. Cyclic voltammogram measurements for the casting films of MWNT-V@PMA nanocomposites revealed four couples of redox waves with cathodic potentials at about -0.56, -0.19, 0.02, 0.21 V, and anodic ones at about -0.46, -0.11, 0.12, 0.31 V (vs Ag/AgCl), respectively, among which the first one corresponded to the electron transfer process of viologens and others to that of the PMA adsorbed. Finally, the MWNT-V@PMA modified electrodes were used as heterogeneous catalysts for the electrocatalytic bromate reduction, which revealed an almost linear correction between the current density and the bromate concentrations in the concentration range from 1 to 15 mmol/l. [Figure not available: see fulltext.

Structural and spectroscopic properties of the second generation phosphorus-viologen "molecular asterisk".

Science.gov (United States)

Furer, V L; Vandukov, A E; Katir, N; Majoral, J P; El Kadib, A; Caminade, A M; Bousmina, M; Kovalenko, V I

2013-11-01

The FTIR and FT Raman spectra of the second generation phosphorus-viologen "molecular asterisk" G2 built from cyclotriphosphazene core with 12 viologen units and 6 terminal phosphonate groups have been recorded and analyzed. The experimental X-ray data of 1,1-bis(4-formylbenzyl)-4,4'-bipyridinium bis(hexaflurophosphate) was used in molecular modeling studies. The optimization of isolated 1,1-bis(4-formylbenzyl)-4,4'-bipyridinium (BFBP) molecule without counter ions PF6(-) does not lead to significant changes of dihedral angles, thus the molecular conformation does not depend on interactions with the counter ions. The structural optimization and normal mode analysis were performed for G2 on the basis of the density functional theory (DFT). The calculated geometrical parameters and harmonic vibrational frequencies are predicted in a good agreement with the experimental data. It was found that G2 has a kind of "egg timer" structure with planar OC6H4CHNN(CH3) fragments and slightly non-planar cyclotriphosphazene core. The experimental IR and Raman spectra of G2 were interpreted by means of potential energy distribution. Copyright © 2013 Elsevier B.V. All rights reserved.

Charge-Transfer Supra-Amphiphiles Built by Water-Soluble Tetrathiafulvalenes and Viologen-Containing Amphiphiles: Supramolecular Nanoassemblies with Modifiable Dimensions.

Science.gov (United States)

Lv, Zhong-Peng; Chen, Bin; Wang, Hai-Ying; Wu, Yue; Zuo, Jing-Lin

2015-08-05

In this study, multidimensional nanoassemblies with various morphologies such as nanosheets, nanorods, and nanofibers are developed via charge-transfer interaction and supra-amphiphile self-assembling in aqueous phase. The charge-transfer interactions between tetrathiafulvalene derivatives (TTFs) and methyl viologen derivatives (MVs) have been confirmed by the characteristic charger-transfer absorption. (1) H NMR and electrospray ionizsation mass spectrometry (ESI-MS) analyses also indicate supra-amphiphiles are formed by the combination of TTFs and MVs head group through charge-transfer interaction and Coulombic force. X-ray single crystal structural studies, transmission electron microscopy (TEM), and scanning electron microscopy (SEM) reveal that both linkage pattern of TTFs in hydrophilic part and alkane chain structure in hydrophobic part have significant influence on nanoassemblies morphology and microstructure. Moreover, gold nanoparticles (AuNPs) are introduced in the above supramolecular nanoassemblies to construct a supra-amphiphile-driven organic-AuNPs assembly system. AuNPs could be assembled into 1D-3D structures by adding different amount of MVs. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Surfactant 1-Hexadecyl-3-methylimidazolium Chloride Can Convert One-Dimensional Viologen Bromoplumbate into Zero-Dimensional.

Science.gov (United States)

Liu, Guangfeng; Liu, Jie; Nie, Lina; Ban, Rui; Armatas, Gerasimos S; Tao, Xutang; Zhang, Qichun

2017-05-15

A zero-dimensional N,N'-dibutyl-4,4'-dipyridinium bromoplumbate, [BV] 6 [Pb 9 Br 30 ], with unusual discrete [Pb 9 Br 30 ] 12- anionic clusters was prepared via a facile surfactant-mediated solvothermal process. This bromoplumbate exhibits a narrower optical band gap relative to the congeneric one-dimensional viologen bromoplumbates.

Overexpression of Iron Superoxide Dismutase in Transformed Poplar Modifies the Regulation of Photosynthesis at Low CO2 Partial Pressures or Following Exposure to the Prooxidant Herbicide Methyl Viologen1

Science.gov (United States)

Arisi, Ana-Carolina M.; Cornic, Gabriel; Jouanin, Lise; Foyer, Christine H.

1998-01-01

Chloroplast-targeted overexpression of an Fe superoxide dismutase (SOD) from Arabidopsis thaliana resulted in substantially increased foliar SOD activities. Ascorbate peroxidase, glutathione reductase, and monodehydroascorbate reductase activities were similar in the leaves from all of the lines, but dehydroascorbate reductase activity was increased in the leaves of the FeSOD transformants relative to untransformed controls. Foliar H2O2, ascorbate, and glutathione contents were comparable in all lines of plants. Irradiance-dependent changes in net CO2 assimilation and chlorophyll a fluorescence quenching parameters were similar in all lines both in air (21% O2) and at low (1%) O2. CO2-response curves for photosynthesis showed similar net CO2-exchange characteristics in all lines. In contrast, values of photochemical quenching declined in leaves from untransformed controls at intercellular CO2 (Ci) values below 200 μL L−1 but remained constant with decreasing Ci in leaves of FeSOD transformants. When the O2 concentration was decreased from 21 to 1%, the effect of FeSOD overexpression on photochemical quenching at limiting Ci was abolished. At high light (1000 μmol m−2 s−1) a progressive decrease in the ratio of variable (Fv) to maximal (Fm) fluorescence was observed with decreasing temperature. At 6oC the high-light-induced decrease in the Fv/Fm ratio was partially prevented by low O2 but values were comparable in all lines. Methyl viologen caused decreased Fv/Fm ratios, but this was less marked in the FeSOD transformants than in the untransformed controls. These observations suggest that the rate of superoxide dismutation limits flux through the Mehler-peroxidase cycle in certain conditions. PMID:9625709

Synthesis of 3-(4,5-dihydroimidazol-1-YL)propyltriethoxysilane bound Ru(II) complex bearing viologen segment

International Nuclear Information System (INIS)

Gurbuz, N.; Seckin, T.; Ozdemir, I.; Cetinkaya, B.

2005-01-01

The nanostructured metallopolymers consisting of the partially quaternized 3-(4,5-dihydroimidazol-1-yl)propyl having the viologen group linked covalently through the alkyl spacer its Ru(II) complex have been prepared by sol-gel method. Structural elucidation was done with Fourier transform infrared spectroscopy, ultraviolet spectroscopy, and differential thermal analysis (DTA) [ru

A π-Conjugation Extended Viologen as a Two-Electron Storage Anolyte for Total Organic Aqueous Redox Flow Batteries.

Science.gov (United States)

Luo, Jian; Hu, Bo; Debruler, Camden; Liu, Tianbiao Leo

2018-01-02

Extending the conjugation of viologen by a planar thiazolo[5,4-d]thiazole (TTz) framework and functionalizing the pyridinium with hydrophilic ammonium groups yielded a highly water-soluble π-conjugation extended viologen, 4,4'-(thiazolo[5,4-d]thiazole-2,5-diyl)bis(1-(3-(trimethylammonio)propyl)pyridin-1-ium) tetrachloride, [(NPr) 2 TTz]Cl 4  , as a novel two-electron storage anolyte for aqueous organic redox flow battery (AORFB) applications. Its physical and electrochemical properties were systematically investigated. Paired with 4-trimethylammonium-TEMPO (N Me -TEMPO) as catholyte, [(NPr) 2 TTz]Cl 4 enables a 1.44 V AORFB with a theoretical energy density of 53.7 Wh L -1 . A demonstrated [(NPr) 2 TTz]Cl 4 /N Me -TEMPO AORFB delivered an energy efficiency of 70 % and 99.97 % capacity retention per cycle. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Reaction of N,N'-dimethylformamide and divalent viologen molecule to generate an organic dopant for molybdenum disulfide

Science.gov (United States)

Fukui, A.; Miura, K.; Ichimiya, H.; Tsurusaki, A.; Kariya, K.; Yoshimura, T.; Ashida, A.; Fujimura, N.; Kiriya, D.

2018-05-01

Tuning the carrier concentration is essential for semiconducting materials to apply optoelectronic devices. Molybdenum disulfide (MoS2) is a semiconducting material composed of atomically thin (˜0.7 nm thickness) layers. To dope thin MoS2, instead of using conventional atom/ion injection processes, a surface charge transfer method was successfully applied. In this study, we report a simple preparation method of a molecular dopant applicable to the doping process. The method follows a previous report for producing a molecular dopant, benzyl viologen (BV) which shows electron doping to MoS2. To prepare dopant BV molecules, a reduction process with a commercially available divalent BV by sodium borohydride (NaBH4) is required; however, the reaction requires a large consumption of NaBH4. NaBH4 drastically reacts with the solvent water itself. We found a reaction process of BV in an organic solvent, N,N'-dimethylformamide (DMF), by adding a small amount of water dissolving the divalent BV. The reaction is mild (at room temperature) and is autonomous once DMF comes into contact with the divalent BV aqueous solution. The reaction can be monitored with a UV-Vis spectrometer, and kinetic analysis indicates two reaction steps between divalent/monovalent/neutral viologen isomers. The product was soluble in toluene and did not dissolve in water, indicating it is similar to the reported dopant BV. The synthesized molecule was found to act as a dopant for MoS2 by applying a metal-oxide-semiconductor field-effect-transistor (MOSFET) structure. The process is a general method and applicable to other viologen-related dopants to tune the electronic structure of 2D materials to facilitate generating atomically thin devices.

Reaction of N,N’-dimethylformamide and divalent viologen molecule to generate an organic dopant for molybdenum disulfide

Directory of Open Access Journals (Sweden)

A. Fukui

2018-05-01

Full Text Available Tuning the carrier concentration is essential for semiconducting materials to apply optoelectronic devices. Molybdenum disulfide (MoS2 is a semiconducting material composed of atomically thin (∼0.7 nm thickness layers. To dope thin MoS2, instead of using conventional atom/ion injection processes, a surface charge transfer method was successfully applied. In this study, we report a simple preparation method of a molecular dopant applicable to the doping process. The method follows a previous report for producing a molecular dopant, benzyl viologen (BV which shows electron doping to MoS2. To prepare dopant BV molecules, a reduction process with a commercially available divalent BV by sodium borohydride (NaBH4 is required; however, the reaction requires a large consumption of NaBH4. NaBH4 drastically reacts with the solvent water itself. We found a reaction process of BV in an organic solvent, N,N’-dimethylformamide (DMF, by adding a small amount of water dissolving the divalent BV. The reaction is mild (at room temperature and is autonomous once DMF comes into contact with the divalent BV aqueous solution. The reaction can be monitored with a UV-Vis spectrometer, and kinetic analysis indicates two reaction steps between divalent/monovalent/neutral viologen isomers. The product was soluble in toluene and did not dissolve in water, indicating it is similar to the reported dopant BV. The synthesized molecule was found to act as a dopant for MoS2 by applying a metal-oxide-semiconductor field-effect-transistor (MOSFET structure. The process is a general method and applicable to other viologen-related dopants to tune the electronic structure of 2D materials to facilitate generating atomically thin devices.

Crystal structures and luminescence properties of two Cd(II) complexes based on 2-(1H-imidazol-1methyl)-6-methyl-1H-benzimidazole

International Nuclear Information System (INIS)

Zhang, Yuhong; Meng, Xiangru; Wen, Yu; Li, Peng; Ma, Lin; Zhang, Qiuju

2015-01-01

Two new complexes, {[Cd(immb)I 2 ].DMF} n (1) and {[Cd 3 (immb)(btc) 2 ]. H 2 O} n (2) (immb = 2-(1H-imidazol- 1-methyl)-6-methyl-1H-benzimidazole, btc = 1,2,3-benzenetricarboxylate, DMF = dimethyl formamide), have been synthesized and characterized. Single crystal X-ray diffraction shows that 1 exhibits a chain structure constructed by immb ligands bridging Cd(II) ions. In 2, Cd(II) ions are linked by immb ligands with bridging mode and btc3- anions with the μ 2 -η 2 :η 1 bonding pattern leading to a 2D structure. Luminescent properties have been investigated in the solid state at room temperature.

The Effect of Number and Position of P=O/P=S Bridging Units on Cavitand Selectivity toward Methyl Ammonium Salts

Directory of Open Access Journals (Sweden)

Daniela Menozzi

2015-03-01

Full Text Available The present work reports the synthesis and complexation properties of five mixed bridge P=O/P=S cavitands toward N,N-methyl butyl ammonium chloride (1 as prototype guest. The influence of number and position of P=O and P=S groups on the affinity of phosphonate cavitands toward 1 is assessed via ITC titrations in DCE as solvent. Comparison of the resulting Kass values, the enthalpic and entropic contributions to the overall binding with those of the parent tetraphosphonate Tiiii and tetrathiophosphonate TSiiii cavitands allows one to single out the simultaneous dual H-bond between the cavitand and the salt as the major player in complexation.

Anaerobic Aryl Reductive Dehalogenation of Halobenzoates by Cell Extracts of “Desulfomonile tiedjei”

OpenAIRE

DeWeerd, Kim A.; Suflita, Joseph M.

1990-01-01

We studied the transformation of halogenated benzoates by cell extracts of a dehalogenating anaerobe, “Desulfomonile tiedjei.” We found that cell extracts possessed aryl reductive dehalogenation activity. The activity was heat labile and dependent on the addition of reduced methyl viologen, but not on that of reduced NAD, NADP, flavin mononucleotide, flavin adenine dinucleotide, desulfoviridin, cytochrome c3, or benzyl viologen. Dehalogenation activity in extracts was stimulated by formate, C...

The reduction of nitrate, nitrite and hydroxylamine to ammonia by enzymes from Cucurbita pepo L. in the presence of reduced benzyl viologen as electron donor

Science.gov (United States)

Cresswell, C. F.; Hageman, R. H.; Hewitt, E. J.; Hucklesby, D. P.

1965-01-01

1. Enzyme systems from Cucurbita pepo have been shown to catalyse the reduction of nitrite and hydroxylamine to ammonia in yields about 90–100%. 2. Reduced benzyl viologen serves as an efficient electron donor for both systems. Activity of the nitrite-reductase system is directly related to degree of dye reduction when expressed in terms of the function for oxidation–reduction potentials, but appears to decrease to negligible activity below about 9% dye reduction. 3. NADH and NADPH alone produce negligible nitrite loss, but NADPH can be linked to an endogenous diaphorase system to reduce nitrite to ammonia in the presence of catalytic amounts of benzyl viologen. 4. The NADH– or NADPH–nitrate-reductase system that is also present can accept electrons from reduced benzyl viologen, but shows relationships opposite to that for the nitrite-reductase system with regard to effect of degree of dye reduction on activity. The product of nitrate reduction may be nitrite alone, or nitrite and ammonia, or ammonia alone, according only to the degree of dye reduction. 5. The relative activities of nitrite-reductase and hydroxylamine-reductase systems show different relationships with degree of dye reduction and may become reversed in magnitude when effects of degree of dye reduction are tested over a suitable range. 6. Nitrite severely inhibits the rate of reduction of hydroxylamine without affecting the yield of ammonia as a percentage of total substrate loss, but hydroxylamine has a negligible effect on the activity of the nitrite-reductase system. 7. The apparent Km for nitrite (1 μm) is substantially less than that for hydroxylamine, for which variable values between 0·05 and 0·9mm (mean 0·51 mm) have been observed. 8. The apparent Km values for reduced benzyl viologen differ for the nitrite-reductase and hydroxylamine-reductase systems: 60 and 7·5 μm respectively. 9. It is concluded that free hydroxylamine may not be an intermediate in the reduction of nitrite

Electrochemical studies of redox probes in self-organized lyotropic ...

Indian Academy of Sciences (India)

Administrator

quinone|hydroquinone, methyl viologen and ferrocenemethanol probes in a lyotropic hexagonal columnar phase (H1 phase) using cyclic voltammetry and electrochemical impedance ..... hydrogen bond of hydroquinone during oxidation is.

Intense Chiroptical Switching in a Dicationic Helicene-Like Derivative: Exploration of a Viologen-Type Redox Manifold of a Non-Racemic Helquat

Czech Academy of Sciences Publication Activity Database

Pospíšil, Lubomír; Bednárová, Lucie; Štěpánek, Petr; Slavíček, P.; Vávra, Jan; Hromadová, Magdaléna; Dlouhá, Helena; Tarábek, Ján; Teplý, Filip

2014-01-01

Roč. 136, č. 31 (2014), s. 10826-10829 ISSN 0002-7863 R&D Projects: GA ČR GA13-19213S Grant - others:GA ČR(CZ) GA13-34168S; GA MŠk(CZ) ED3.2.00/08.0144 Institutional support: RVO:61388963 ; RVO:61388955 Keywords : helicenoids * helquats * helical cations * ECD spectra * redox switching * chiroptical properties * helicene-viologen hybrids Subject RIV: CC - Organic Chemistry Impact factor: 12.113, year: 2014

Bridging the Gap Between Protein Carboxyl Methylation and Phospholipid Methylation to Understand Glucose-Stimulated Insulin Secretion From the Pancreatic β Cell

OpenAIRE

Kowluru, Anjaneyulu

2007-01-01

Recent findings have implicated post-translational modifications at C-terminal cysteines [e.g., methylation] of specific proteins [e.g., G-proteins] in glucose-stimulated insulin secretion [GSIS]. Furthermore, methylation at the C-terminal leucine of the catalytic subunit of protein phosphatase 2A [PP2Ac] has also been shown to be relevant for GSIS. In addition to these two classes of protein methyl transferases, a novel class of glucose-activated phospholipid methyl transferases have also be...

Bridging the gap between protein carboxyl methylation and phospholipid methylation to understand glucose-stimulated insulin secretion from the pancreatic beta cell.

Science.gov (United States)

Kowluru, Anjaneyulu

2008-01-15

Recent findings have implicated post-translational modifications at C-terminal cysteines [e.g., methylation] of specific proteins [e.g., G-proteins] in glucose-stimulated insulin secretion [GSIS]. Furthermore, methylation at the C-terminal leucine of the catalytic subunit of protein phosphatase 2A [PP2Ac] has also been shown to be relevant for GSIS. In addition to these two classes of protein methyl transferases, a novel class of glucose-activated phospholipid methyl transferases have also been identified in the beta cell. These enzymes catalyze three successive methylations of phosphatidylethanolamine to yield phosphatidylcholine. The "newly formed" phosphatidylcholine is felt to induce alterations in the membrane fluidity, which might favor vesicular fusion with the plasma membrane for the exocytosis of insulin. The objectives of this commentary are to: (i) review the existing evidence on the regulation, by glucose and other insulin secretagogues, of post-translational carboxylmethylation [CML] of specific proteins in the beta cell; (ii) discuss the experimental evidence, which implicates regulation, by glucose and other insulin secretagogues, of phosphatidylethanolamine methylation in the islet beta cell; (iii) propose a model for potential cross-talk between the protein and lipid methylation pathways in the regulation of GSIS and (iv) highlight potential avenues for future research, including the development of specific pharmacological inhibitors to further decipher regulatory roles for these methylation reactions in islet beta cell function.

High proton conductivity in cyanide-bridged metal-organic frameworks: understanding the role of water

NARCIS (Netherlands)

Gao, Y.; Broersen, R.; Hageman, W.; Yan, N.; Mittelmeijer-Hazeleger, M.; Rothenberg, G.; Tanase, S.

2015-01-01

We investigate and discuss the proton conductivity properties of the cyanide-bridged metal–organic framework (MOF) [Nd(mpca)2Nd(H2O)6Mo(CN)8]·nH2O (where mpca is 5-methyl-2-pyrazinecarboxylate). This MOF is one of an exciting class of cyanide-bridged materials that can combine porosity with

A Tri-O-Bridged Diels-Alder Adduct from Cortex Mori Radicis

Directory of Open Access Journals (Sweden)

An-Qi Lu

2018-01-01

Full Text Available Sanggenon X, an unusual tri-O-bridged Diels-Alder adduct, was isolated from Cortex Mori Radicis. Its structure was established by spectroscopic analysis, including NMR and HR-MS (High Resolution Mass Spectrometry. Sanggenon X contained three O-bridged rings, where the oxygenated bridgeheads were all quaternary carbons. Chemical methylation was carried out to deduce the linkages of the three O-bridges. The absolute configuration was determined by calculating the ECD (Electronic Circular Dichroism using the TDDFT (Time-Dependent Density Functional Theory method. Sanggenon X showed significant antioxidant activity against Fe2+-Cys-induced lipid peroxidation in rat liver microsomes, and was as effective as the positive control, curcumin.

Enhanced photocurrent in RuL2(NCS)2/di-(3-aminopropyl)-viologen/SnO2/ITO system

International Nuclear Information System (INIS)

Lee, Wonjoo; Kwak, Chang Gon; Mane, R.S.; Min, Sun Ki; Cai, Gangri; Ganesh, T.; Koo, Gumae; Chang, Jinho; Cho, Byung Won; Kim, Sei-Ki; Han, Sung-Hwan

2008-01-01

A Ru(2,2'-bipyridine-4,4'-dicarboxylic acid) 2 (NCS) 2 [RuL 2 (NCS) 2 ]/di-(3-aminopropyl)-viologen (DAPV)/tin oxide (SnO 2 ) system was prepared and applied to extensive photocurrent generation with its maximum surface area. The SnO 2 thin films on tin-doped indium oxide (ITO) were prepared using the chemical bath deposition method. Then, RuL 2 (NCS) 2 /DAPV on SnO 2 /ITO was easily prepared using self-assembled monolayers (SAMs). The photocurrent measurement of the system showed an excellent photocurrent of 20 nA cm -2 under the air mass 1.5 conditions (100 mW cm -2 ), which was increased by a factor of four compared to ones without SnO 2 layers

Synthesis, Characterization and Application of A Novel Carbon Bridged Half-metallocene Chromium Catalyst for Methyl Methacrylate Polymerization

Institute of Scientific and Technical Information of China (English)

CHENG Zhengzai; GONG Kai; WANG Yang; ZHOU Xue; ZHANG Weixing; LI Yin; SUN Junquan; LI Wenbing

2014-01-01

A new carbon bridged cyclopentadienyl chromium complex of the type [(C5H4)C(CH3)2 CH2(C5H4N)]CrCl2 was prepared by treatment of CrCl3•(THF)3 in THF solution with the lithium salt of ligand containing cyclopentadienyl and pyridyl groups. The chromium complex was characterized by 1H NMR and elemental analysis(EA), and the crystal structure was determined by X-ray diffraction analysis. Activated by Al(i-Bu)3, the chromium complex displayed a very high activity for methyl methacrylate (MMA) polymerization. After 24 hours,more than 95.5%MMA was converted to polymethyl methacrylate (PMMA) with a viscosity average molecular weight (Wη) of 416000 g•mol-1 at 60℃for MMA/Al(i-Bu)3/chromium catalyst molar ratio of up to 2000:20:1. Effects of temperature, molar ratios of MMA/catalyst and catalyst/cocatalyst on the polymerization have been studied. The high conversion of MMA and high molecular weight of PMMA with narrow molecular weight distribution is caused by the unique stable active site formed by the new chromium complex and aluminum cocatalyst.

Reproductive organ and vascular specific promoter of the rice plasma membrane Ca2+ATPase mediates environmental stress responses in plants.

Science.gov (United States)

Huda, Kazi Md Kamrul; Banu, Mst Sufara Akhter; Pathi, Krishna Mohan; Tuteja, Narendra

2013-01-01

Plasma membrane Ca(2+)ATPase is a transport protein in the plasma membrane of cells and helps in removal of calcium (Ca(2+)) from the cell, hence regulating Ca(2+) level within cells. Though plant Ca(2+)ATPases have been shown to be involved in plant stress responses but their promoter regions have not been well studied. The 1478 bp promoter sequence of rice plasma membrane Ca(2+)ATPase contains cis-acting elements responsive to stresses and plant hormones. To identify the functional region, serial deletions of the promoter were fused with the GUS sequence and four constructs were obtained. These were differentially activated under NaCl, PEG cold, methyl viologen, abscisic acid and methyl jasmonate treatments. We demonstrated that the rice plasma membrane Ca(2+)ATPase promoter is responsible for vascular-specific and multiple stress-inducible gene expression. Only full-length promoter showed specific GUS expression under stress conditions in floral parts. High GUS activity was observed in roots with all the promoter constructs. The -1478 to -886 bp flanking region responded well upon treatment with salt and drought. Only the full-length promoter presented cold-induced GUS expression in leaves, while in shoots slight expression was observed for -1210 and -886 bp flanking region. The -1210 bp deletion significantly responded to exogenous methyl viologen and abscisic acid induction. The -1210 and -886 bp flanking region resulted in increased GUS activity in leaves under methyl jasmonate treatments, whereas in shoots the -886 bp and -519 bp deletion gave higher expression. Salicylic acid failed to induce GUS activities in leaves for all the constructs. The rice plasma membrane Ca(2+)ATPase promoter is a reproductive organ-specific as well as vascular-specific. This promoter contains drought, salt, cold, methyl viologen, abscisic acid and methyl jasmonate related cis-elements, which regulated gene expression. Overall, the tissue-specificity and inducible nature of this

Reproductive organ and vascular specific promoter of the rice plasma membrane Ca2+ATPase mediates environmental stress responses in plants.

Directory of Open Access Journals (Sweden)

Kazi Md Kamrul Huda

Full Text Available Plasma membrane Ca(2+ATPase is a transport protein in the plasma membrane of cells and helps in removal of calcium (Ca(2+ from the cell, hence regulating Ca(2+ level within cells. Though plant Ca(2+ATPases have been shown to be involved in plant stress responses but their promoter regions have not been well studied.The 1478 bp promoter sequence of rice plasma membrane Ca(2+ATPase contains cis-acting elements responsive to stresses and plant hormones. To identify the functional region, serial deletions of the promoter were fused with the GUS sequence and four constructs were obtained. These were differentially activated under NaCl, PEG cold, methyl viologen, abscisic acid and methyl jasmonate treatments. We demonstrated that the rice plasma membrane Ca(2+ATPase promoter is responsible for vascular-specific and multiple stress-inducible gene expression. Only full-length promoter showed specific GUS expression under stress conditions in floral parts. High GUS activity was observed in roots with all the promoter constructs. The -1478 to -886 bp flanking region responded well upon treatment with salt and drought. Only the full-length promoter presented cold-induced GUS expression in leaves, while in shoots slight expression was observed for -1210 and -886 bp flanking region. The -1210 bp deletion significantly responded to exogenous methyl viologen and abscisic acid induction. The -1210 and -886 bp flanking region resulted in increased GUS activity in leaves under methyl jasmonate treatments, whereas in shoots the -886 bp and -519 bp deletion gave higher expression. Salicylic acid failed to induce GUS activities in leaves for all the constructs.The rice plasma membrane Ca(2+ATPase promoter is a reproductive organ-specific as well as vascular-specific. This promoter contains drought, salt, cold, methyl viologen, abscisic acid and methyl jasmonate related cis-elements, which regulated gene expression. Overall, the tissue-specificity and inducible

Pulse Radiolysis of Methyl Viologen in Aqueous Solutions

DEFF Research Database (Denmark)

Solar, S.; Solar, W.; Getoff, N.

1982-01-01

dm3 mol–1 s–1, absorbs at 310 nm (ε310= 900 m2 mol–1) and 470 nm (ε470= 630 m2 mol–1) and decays by conversion into MV˙+H+ in a first-order process with k= 6 × 103 s–1. For the equilibrium MV˙+H+ MV˙++ H+ pK= 2.9 ± 0.1 was determined. The presented data explain, at least partly, the instability...

TECHNICAL REPORT

Energy Technology Data Exchange (ETDEWEB)

ADAMS, RICHARD D., PhD.

2011-04-06

Cadmium selenide nanoparticles and nanoclusters were prepared and added to polymer solar cells to improve their photon capture ability. These nanoparticles did exhibit some beneficial effects on the photon conversion efficiencies of selected polymer solar cells. Ternary bulk heterojunction systems based on composites of methyl viologen-doped, CdSe nanoparticles blended with poly (3-hexothiopene) (P3HT) and 6, 6-phenyl C{sub 61}-butyric acid methyl ester (PCBM) were also tested. It was found that the devices with methyl viologen-doped CdSe nanoparticles do produce more photocurrent in a region surrounding the absorption peak of the particles (560 to 660nm) when compared to pristine P3HT:PCBM devices. Gold nanorods were also prepared and tested in some solar cells. These nanorods did produce a very small enhancement in photon absorbance, but the observed increase the photon conversion efficiency was not sufficient to make the effort worthwhile. Our goals were (1) to prepare cadmium sulfide and cadmium selenide clusters and nanoparticles to be tested as photon absorbers to enhance the photon conversion efficiency of polymer solar polymer solar cells and (2) to prepare gold and silver nanorods to be added to polymer solar cells to enhance their photon capture capability. The cadmium sulfide and cadmium selenide nanoparticles and some new nanoclusters were prepared. The cadmium selenide nanoparticles were also tested in solar cells and did exhibit some positive effects when they were combined with certain co-absorbing polymers. Due to solubility problems that were not solved in the available time, the new nanoclusters were not tested in solar cells. Ternary bulk heterojunction systems based on composites of methyl viologen doped, CdSe nanoparticles blended with poly (3-hexothiopene) (P3HT) and 6, 6-phenyl C61-butyric acid methyl ester (PCBM) have been examined in detail. The methyl viologen was added to promote charge separation of the initially formed excitons. It was

Promising Low-Toxicity of Viologen-Phosphorus Dendrimers against Embryonic Mouse Hippocampal Cells

Directory of Open Access Journals (Sweden)

Jean-Pierre Majoral

2013-09-01

Full Text Available A new class of viologen-phosphorus dendrimers (VPDs has been recently shown to possess the ability to inhibit neurodegenerative processes in vitro. Nevertheless, in the Central Nervous Systems domain, there is little information on their impact on cell functions, especially on neuronal cells. In this work, we examined the influence of two VPD (VPD1 and VPD3 of zero generation (G0 on murine hippocampal cell line (named mHippoE-18. Extended analyses of cell responses to these nanomolecules comprised cytotoxicity test, reactive oxygen species (ROS generation studies, mitochondrial membrane potential (ΔΨm assay, cell death detection, cell morphology assessment, cell cycle studies, as well as measurements of catalase (CAT activity and glutathione (GSH level. The results indicate that VPD1 is more toxic than VPD3. However, these two tested dendrimers did not cause a strong cellular response, and induced a low level of apoptosis. Interestingly, VPD1 and VPD3 treatment led to a small decline in ROS level compared to untreated cells, which correlated with slightly increased catalase activity. This result indicates that the VPDs can indirectly lower the level of ROS in cells. Summarising, low-cytotoxicity on mHippoE-18 cells together with their ability to quench ROS, make the VPDs very promising nanodevices for future applications in the biomedical field as nanocarriers and/or drugs per se.

Synthesis and Characterization of Ru(II) Tris(1,1O-phenanthroline)-Electron Acceptor Dyads Incorporating the 4-benzoyl-N-methylpyridinium Cation or N-Benzyl-N'-methyl-viologen. Improving the Dynamic Range, Sensitivity and Response Time of Sol-Gel Based Optical Oxygen Sensors

Science.gov (United States)

Leventis, Nicholas; Rawashdeh, Abdel-Monen M.; Elder, Ian A.; Yang, Jinhua; Dass, Amala; Sotiriou-Leventis, Chariklia

2004-01-01

The title compounds (1 and 2, above) were synthesized by Sonogashira coupling reactions of appropriate Ru(1I) complexes with the electron a cceptors. Characterization was conducted in solution and in frozen ma trices. Finally, the title compounds were evaluated as dopants of sol-gel materials. It was found that the intramolecular quenching efficie ncy of 4-benzoyl-Nmethylpyridinium cation in solution depends on the solvent: photoluminescence is quenched completely in CH,CN, but not i n methanol or ethanol. On the other hand, intramolecular emission que nching by 4-benzyl-N-methyl viologen is complete in all solvents. The difference between the two quenchers is traced electrochemically to t he solvation of the 4-benzoyl-Nmethylpyridiniums by alcohol. In froze n matrices or adsorbed on the surfaces of silica aerogel, both Ru(I1) complex/electron acceptor dyads of this study are photoluminescent, and the absence of quenching has been traced to the environmental rigi dity. When doped aerogels are cooled at 77 K, the emission intensity increases by approximately 4x, and the spectra shift to the blue, analogous to what is observed with Ru(I1) complexes in solutions undergoi ng fluid-to-rigid transition. However, in contrast to frozen solution s, the luminescent moieties in the bulk of aerogels kept at low tempe ratures are still accessible to gas-phase quenchers diffusing through the mesopores, leading to more sensitive platforms for sensors than o ther room-temperature configurations. Thus the photoluminescence of o ur Ru(I1) complex dyads adsorbed on aerogel is quenchable by O2 both at room temperature and at 77 K. Furthermore, it was also found that O 2 modulates the photoluminescence of aerogels doped with 4-benzoyl -N -methylpyridinium-based dyads over a wider dynamic range compared wi th aerogels doped with either our vislogen-based dyads or with Ru(I1) tris(1,lO-phenanthroline) itself.

Experimental vapor pressures (from 1 Pa to 100 kPa) of six saturated Fatty Acid Methyl Esters (FAMEs): Methyl hexanoate, methyl octanoate, methyl decanoate, methyl dodecanoate, methyl tetradecanoate and methyl hexadecanoate

International Nuclear Information System (INIS)

Sahraoui, Lakhdar; Khimeche, Kamel; Dahmani, Abdallah; Mokbel, Ilham; Jose, Jacques

2016-01-01

Highlight: • Vapor-liquid equilibria, Enthalpy of Vaporization, saturated Fatty Acid Methyl Ester. - Abstract: Vapor pressures of six saturated Fatty Acid Methyl Esters (FAMEs), methyl hexanoate (or methyl caproate), methyl octanoate (or methyl caprylate), Methyl decanoate (or methyl caprate), methyl dodecanoate (or methyl laurate), methyl tetradecanoate (or methyl myristate), and methyl hexadecanoate (or methyl palmitate) were measured from 1 Pa to 100 kPa and at temperature range between 262 and 453 K using a static apparatus. The experimental data (P-T) were compared with the available literature data.

Electricity generation using microbial fuel cells

Energy Technology Data Exchange (ETDEWEB)

Mohan, Y.; Manoj Muthu Kumar, S.; Das, D. [Department of Biotechnology, Indian Institute of Technology, Kharagpur 721302 (India)

2008-01-15

Conversion of biomass into electricity is possible using microbial fuel cells (MFCs). The present paper deals with the studies of a two-chambered salt bridge MFC using Enterobacter cloacae IIT-BT 08 in MYG medium. The effect of different electron mediators, concentration of the mediator, ionic strength (salt concentration) of the medium and the surface area of the salt-bridge in contact with the anode and cathode chambers on the power generation in MFCs are reported. In the case of methyl viologen (MV) (0.1 mM) as the electron mediator, the voltage generation was 0.4 V but no current was detected. Different concentrations of methylene blue (MB) were also studied as the mediator. A maximum voltage of 0.37 V was seen at 0.05 mM MB, whereas a maximum current and power of 56.7{mu} A and 19.2{mu} W, respectively, were observed in the case of 0.03 mM MB with a voltage of 0.34 V. The corresponding power density and current density of 9.3mW/m{sup 2} and 27.6mA/m{sup 2}, respectively, were obtained. When the surface area of the salt bridge in contact with the anode and cathode chambers was increased, a proportionate improvement in the power output from 19.2 to 708{mu} W was detected. The maximum power density and current density of 236mW/m{sup 2} and 666.7mA/m{sup 2}, respectively, which are found to be very promising for a salt bridge MFC were observed. (author)

Neuronal DNA Methylation Profiling of Blast-Related Traumatic Brain Injury.

Science.gov (United States)

Haghighi, Fatemeh; Ge, Yongchao; Chen, Sean; Xin, Yurong; Umali, Michelle U; De Gasperi, Rita; Gama Sosa, Miguel A; Ahlers, Stephen T; Elder, Gregory A

2015-08-15

Long-term molecular changes in the brain resulting from blast exposure may be mediated by epigenetic changes, such as deoxyribonucleic acid (DNA) methylation, that regulate gene expression. Aberrant regulation of gene expression is associated with behavioral abnormalities, where DNA methylation bridges environmental signals to sustained changes in gene expression. We assessed DNA methylation changes in the brains of rats exposed to three 74.5 kPa blast overpressure events, conditions that have been associated with long-term anxiogenic manifestations weeks or months following the initial exposures. Rat frontal cortex eight months post-exposure was used for cell sorting of whole brain tissue into neurons and glia. We interrogated DNA methylation profiles in these cells using Expanded Reduced Representation Bisulfite Sequencing. We obtained data for millions of cytosines, showing distinct methylation profiles for neurons and glia and an increase in global methylation in neuronal versus glial cells (pDNA methylation perturbations in blast overpressure-exposed animals, compared with sham blast controls, within 458 and 379 genes in neurons and glia, respectively. Differentially methylated neuronal genes showed enrichment in cell death and survival and nervous system development and function, including genes involved in transforming growth factor β and nitric oxide signaling. Functional validation via gene expression analysis of 30 differentially methylated neuronal and glial genes showed a 1.2 fold change in gene expression of the serotonin N-acetyltransferase gene (Aanat) in blast animals (pDNA methylation induced in response to multiple blast overpressure exposures. In particular, increased methylation and decreased gene expression were observed in the Aanat gene, which is involved in converting serotonin to the circadian hormone melatonin and is implicated in sleep disturbance and depression associated with traumatic brain injury.

Magnetic Field Effects on Photoelectrochemical Reactions of Porphyrin-Viologen Linked Compounds in an Ionic Liquid

Science.gov (United States)

Tahara, Hironobu; Yonemura, Hiroaki; Harada, Satoko; Yamada, Sunao

2011-08-01

Magnetic field effects (MFEs) on photoelectrochemical reactions of three porphyrin-viologen linked compounds with various methylene groups [ZnP(n)V (n=4,6,8)] were examined in 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]) as an ionic liquid using a two-electrode cell. Stable anodic photocurrents are produced by irradiating ZnP(n)V (n=4,6,8) in [BMIM][BF4] with visible light, and the MFEs on photocurrents were clearly observed in ZnP(n)V (n=4,6,8). The MFEs on photocurrents increase with magnetic field for lower magnetic fields (B ≤200 mT) and are constant for higher magnetic fields (B > 200 mT). The magnitude of the MFEs in ZnP(n)V (n=6,8) are larger than that in ZnP(4)V. The MFEs can be explained by radical pair mechanism. The magnitude of the MFEs is larger than those in electrodes modified with ZnP(n)V (n=4,6,8) as Langmuir-Blodgett films. The results are most likely attributable to the properties of [BMIM][BF4] and the mechanism of photoelectrochemical reaction.

BDNF rs6265 methylation and genotype interact on risk for schizophrenia.

Science.gov (United States)

Ursini, Gianluca; Cavalleri, Tommaso; Fazio, Leonardo; Angrisano, Tiziana; Iacovelli, Luisa; Porcelli, Annamaria; Maddalena, Giancarlo; Punzi, Giovanna; Mancini, Marina; Gelao, Barbara; Romano, Raffaella; Masellis, Rita; Calabrese, Francesca; Rampino, Antonio; Taurisano, Paolo; Di Giorgio, Annabella; Keller, Simona; Tarantini, Letizia; Sinibaldi, Lorenzo; Quarto, Tiziana; Popolizio, Teresa; Caforio, Grazia; Blasi, Giuseppe; Riva, Marco A; De Blasi, Antonio; Chiariotti, Lorenzo; Bollati, Valentina; Bertolino, Alessandro

2016-01-01

Epigenetic mechanisms can mediate gene-environment interactions relevant for complex disorders. The BDNF gene is crucial for development and brain plasticity, is sensitive to environmental stressors, such as hypoxia, and harbors the functional SNP rs6265 (Val(66)Met), which creates or abolishes a CpG dinucleotide for DNA methylation. We found that methylation at the BDNF rs6265 Val allele in peripheral blood of healthy subjects is associated with hypoxia-related early life events (hOCs) and intermediate phenotypes for schizophrenia in a distinctive manner, depending on rs6265 genotype: in ValVal individuals increased methylation is associated with exposure to hOCs and impaired working memory (WM) accuracy, while the opposite is true for ValMet subjects. Also, rs6265 methylation and hOCs interact in modulating WM-related prefrontal activity, another intermediate phenotype for schizophrenia, with an analogous opposite direction in the 2 genotypes. Consistently, rs6265 methylation has a different association with schizophrenia risk in ValVals and ValMets. The relationships of methylation with BDNF levels and of genotype with BHLHB2 binding likely contribute to these opposite effects of methylation. We conclude that BDNF rs6265 methylation interacts with genotype to bridge early environmental exposures to adult phenotypes, relevant for schizophrenia. The study of epigenetic changes in regions containing genetic variation relevant for human diseases may have beneficial implications for the understanding of how genes are actually translated into phenotypes.

Development kinetics of silver clusters on silver halides

International Nuclear Information System (INIS)

Grzesiak, S.; Belloni, J.; Marignier, J.-L.

2008-01-01

Silver nuclei are produced by pulse radiolysis at the surface of AgCl nanocrystallites in the presence of an electron donor, the methyl viologen, which induces the growth of silver nuclei. The experimental results observed on the increase of the silver atom concentration and on the decay of the donor concentration during this process, which is similar to the photographic development by an electron donor, are compared with the kinetics obtained from numerical simulation. The model assumes that the formation of silver clusters with a supercritical nuclearity is required before the start of an electron transfer reaction from the two reduced forms of the donor methyl viologen to the silver clusters. The reaction is controlled by the access of the donor to the surface sites of the AgCl crystallite. The rate constant values of the successive steps of the mechanism are derived from the adjustment of calculated kinetics to experimental signals under various conditions, using a single set of parameters which are fairly suitable under all conditions studied

A diketiminate-bound diiron complex with a bridging carbonate ligand

Science.gov (United States)

Sadique, Azwana R.; Brennessel, William W.; Holland, Patrick L.

2009-01-01

Reduction of carbon dioxide by a diiron(I) complex gives μ-carbonato-κ3 O:O′,O′′-bis­{[2,2,6,6-tetra­methyl-3,5-bis­(2,4,6-triisopropyl­phenyl)heptane-2,5-diiminate(1−)-κ2 N,N′]iron(II)} toluene disolvate, [Fe2(C41H65N)2(CO3)]·2C7H8, a diiron(II) species with a bridging carbonate ligand. The asymmetric unit contains one diiron complex and two cocrystallized toluene solvent mol­ecules that are distributed over three sites, one with atoms in general positions and two in crystallographic sites. Both FeII atoms are η2-coordinated to diketiminate ligands, but η1- and η2-coordinated to the bridging carbonate ligand. Thus, one FeII center is three-coordinate and the other is four-coordinate. The bridging carbonate ligand is nearly perpendicular to the iron–diketiminate plane of the four-coordinate FeII center and parallel to the plane of the three-coordinate FeII center. PMID:19407402

47 CFR 80.1007 - Bridge-to-bridge radiotelephone installation.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Bridge-to-bridge radiotelephone installation. 80.1007 Section 80.1007 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Bridge-to-Bridge Act § 80.1007 Bridge-to-bridge radiotelephone installation. Use of the bridge-to-bridge...

Color stability and flexural strength of poly (methyl methacrylate) and bis-acrylic composite based provisional crown and bridge auto-polymerizing resins exposed to beverages and food dye: an in vitro study.

Science.gov (United States)

Gujjari, Anil K; Bhatnagar, Vishrut M; Basavaraju, Ravi M

2013-01-01

To evaluate the color stability and flexural strength of poly (methyl methacrylate) (PMMA) and bis-acrylic composite based provisional crown and bridge auto-polymerizing resins exposed to tea, coffee, cola, and food dye. Two provisional crown and bridge resins, one DPI self-cure tooth molding powder (PMMA) (Group A), and one Protemp 4 Temporization Material (bis-acrylic composite) (Group B) were used. Disk-shaped specimens for color stability testing (n = 30 for each material) and bar-shaped specimens for flexural strength testing (n = 30 for each material) were fabricated using a metal mold. The specimens were immersed in artificial saliva, artificial saliva + tea, artificial saliva + coffee, artificial saliva + cola, and artificial saliva + food dye solutions and stored in an incubator at 37°C. Color measurements were taken before immersion, and then after 3 and 7 days of immersion. Flexural strength was evaluated after 7 days of immersion. Group A showed significantly higher color stability as compared to Group B, and artificial saliva + coffee solution had the most staining capacity for the resins. Test solutions had no effect on the flexural strength of Group A, but Group B specimens immersed in artificial saliva + cola showed significantly lower flexural strength values as compared to the control group. The findings of the study showed that for materials used in the study, PMMA was more color stable than bis-acrylic composite based resin. Also, material based on PMMA was more resistant to damage from dietary beverages as compared to bis-acrylic composite based provisional crown and bridge resin.

Methyl-Analyzer--whole genome DNA methylation profiling.

Science.gov (United States)

Xin, Yurong; Ge, Yongchao; Haghighi, Fatemeh G

2011-08-15

Methyl-Analyzer is a python package that analyzes genome-wide DNA methylation data produced by the Methyl-MAPS (methylation mapping analysis by paired-end sequencing) method. Methyl-MAPS is an enzymatic-based method that uses both methylation-sensitive and -dependent enzymes covering >80% of CpG dinucleotides within mammalian genomes. It combines enzymatic-based approaches with high-throughput next-generation sequencing technology to provide whole genome DNA methylation profiles. Methyl-Analyzer processes and integrates sequencing reads from methylated and unmethylated compartments and estimates CpG methylation probabilities at single base resolution. Methyl-Analyzer is available at http://github.com/epigenomics/methylmaps. Sample dataset is available for download at http://epigenomicspub.columbia.edu/methylanalyzer_data.html. fgh3@columbia.edu Supplementary data are available at Bioinformatics online.

Rhodamine B induces long nucleoplasmic bridges and other nuclear anomalies in Allium cepa root tip cells.

Science.gov (United States)

Tan, Dehong; Bai, Bing; Jiang, Donghua; Shi, Lin; Cheng, Shunchang; Tao, Dongbing; Ji, Shujuan

2014-03-01

The cytogenetic toxicity of rhodamine B on root tip cells of Allium cepa was investigated. A. cepa were cultured in water (negative control), 10 ppm methyl methanesulfonate (positive control), and three concentrations of rhodamine B (200, 100, and 50 ppm) for 7 days. Rhodamine B inhibited mitotic activity; increased nuclear anomalies, including micronuclei, nuclear buds, and bridged nuclei; and induced oxidative stress in A. cepa root tissues. Furthermore, a substantial amount of long nucleoplasmic bridges were entangled together, and some nuclei were simultaneously linked to several other nuclei and to nuclear buds with nucleoplasmic bridges in rhodamine B-treated cells. In conclusion, rhodamine B induced cytogenetic effects in A. cepa root tip cells, which suggests that the A. cepa root is an ideal model system for detecting cellular interactions.

Electrochemical Single-Molecule Transistors with Optimized Gate Coupling

DEFF Research Database (Denmark)

Osorio, Henrry M.; Catarelli, Samantha; Cea, Pilar

2015-01-01

Electrochemical gating at the single molecule level of viologen molecular bridges in ionic liquids is examined. Contrary to previous data recorded in aqueous electrolytes, a clear and sharp peak in the single molecule conductance versus electrochemical potential data is obtained in ionic liquids....... These data are rationalized in terms of a two-step electrochemical model for charge transport across the redox bridge. In this model the gate coupling in the ionic liquid is found to be fully effective with a modeled gate coupling parameter, ξ, of unity. This compares to a much lower gate coupling parameter...

47 CFR 80.331 - Bridge-to-bridge communication procedure.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Bridge-to-bridge communication procedure. 80..., Alarm, Urgency and Safety Procedures § 80.331 Bridge-to-bridge communication procedure. (a) Vessels subject to the Bridge-to-Bridge Act transmitting on the designated navigational frequency must conduct...

Purification and characterization of [Fe]-hydrogenase from high yielding hydrogen-producing strain, Enterobacter cloacae IIT-BT08 (MTCC 5373)

Energy Technology Data Exchange (ETDEWEB)

Dutta, Tumpa; Das, Amit Kumar; Das, Debabrata [Department of Biotechnology, Indian Institute of Technology, Kharagpur, WB 721302 (India)

2009-09-15

Fe-hydrogenase from Enterobacter cloacae IIT-BT08 was purified 1284 fold with specific activity of 335 {mu}mol H{sub 2}/min/mg protein for hydrogen evolution using reduced methyl viologen as an electron-donor at 25 C. The molecular weight of the monomeric enzyme was determined to be 51 kDa by MALDI-ToF mass spectrometry. The PI of the enzyme was {proportional_to}5.6 displaying its acidic nature. The optimal temperature and pH for hydrogen evolution was 37 C and 7-7.2 respectively. The affinity constant, K{sub m} for reduced methyl viologen was 0.57 {+-} 0.03 mM and that of reduced ferredoxin was 0.72 {+-} 0.04 {mu}M. The enzyme contained {proportional_to}11.47 gm-atom Fe/mol of Fe-hydrogenase. Electron paramagnetic resonance analysis ascertained the existence of iron molecules as [4Fe-4S] clusters. The internal amino acid sequences of trypsin digested peptides of hydrogenase as determined by ESI MS/MS Q-ToF showed 80-87% identities with the respective sequences of Clostridium sp. and Trichomonas sp. hydrogenase. (author)

Untitled

Indian Academy of Sciences (India)

Iot A a. (1) pH - 108. ------ -----. -200 -800 -400 O - 1200 -800 - 400 0. mV NHE mv NHE. Figure 3. CV of 1 and 2 at pH = 108. The voltammograms of compound 1 and 2 are more complex than, for example, those of methyl viologen. Shoulders, appearing in the CV's of 1 and 2, indicate competing reactions. Rapid reversible or ...

Determination of one-electron reduction potentials of some radiosensitive compounds by pulse radiolysis

International Nuclear Information System (INIS)

Zuo Zhihua; Yao Side; Li Hucheng; Lin Nianyun; Jin Yizun

1994-01-01

One-electron reduction potential (E 7 1 ) is one of the important parameters of radiosensitive compound with high electron affinity. In this work one-electron reduction potentials of some radiosensitizers, such as Miso, 911, CMNa, SMU-1, SMU-2, SMD, SNN, S 3 and BSO, were determined pulse radiolytically by using anthraquinone-2-sulfate (AQS), duroquinone (DQ) and methyl viologen (MV 2+ ) as references

Color stability and flexural strength of poly (methyl methacrylate and bis-acrylic composite based provisional crown and bridge auto-polymerizing resins exposed to beverages and food dye: An in vitro study

Directory of Open Access Journals (Sweden)

Anil K Gujjari

2013-01-01

Full Text Available Aim: To evaluate the color stability and flexural strength of poly (methyl methacrylate (PMMA and bis-acrylic composite based provisional crown and bridge auto-polymerizing resins exposed to tea, coffee, cola, and food dye. Materials and Methods: Two provisional crown and bridge resins, one DPI self-cure tooth molding powder (PMMA (Group A, and one Protemp 4 Temporization Material (bis-acrylic composite (Group B were used. Disk-shaped specimens for color stability testing (n = 30 for each material and bar-shaped specimens for flexural strength testing (n = 30 for each material were fabricated using a metal mold. The specimens were immersed in artificial saliva, artificial saliva + tea, artificial saliva + coffee, artificial saliva + cola, and artificial saliva + food dye solutions and stored in an incubator at 37°C. Color measurements were taken before immersion, and then after 3 and 7 days of immersion. Flexural strength was evaluated after 7 days of immersion. Results: Group A showed significantly higher color stability as compared to Group B, and artificial saliva + coffee solution had the most staining capacity for the resins. Test solutions had no effect on the flexural strength of Group A, but Group B specimens immersed in artificial saliva + cola showed significantly lower flexural strength values as compared to the control group. Conclusion: The findings of the study showed that for materials used in the study, PMMA was more color stable than bis-acrylic composite based resin. Also, material based on PMMA was more resistant to damage from dietary beverages as compared to bis-acrylic composite based provisional crown and bridge resin.

Cyclodextrin ketones as oxidation catalysts: investigation of bridged derivatives

DEFF Research Database (Denmark)

Fenger, Thomas Hauch; Marinescu, Lavinia; Bols, Mikael

2009-01-01

A series of alpha-cyclodextrin derivatives containing a 3, 4 or 5 membered ether-linked bridge between the 6A and 6D oxygen atoms, with and without a ketone, were prepared. The synthesis used perbenzylated alpha-cyclodextrin A,D-diol as a starting material upon which O-alkylation and further modi...... derivatives were also made. The 6A,6D-di-O-(propa-2-on-1,3-diyl)-6C,6F-di-O-methyl and di-O-pivaloyl derivatives were also prepared. The new compounds were analysed for catalysis of the oxidation of amines and alcohols....

Myocardial Bridge

Science.gov (United States)

... Center > Myocardial Bridge Menu Topics Topics FAQs Myocardial Bridge En español Your heart is made of muscle, ... surface of the heart. What is a myocardial bridge? A myocardial bridge is a band of heart ...

Fragrance material review on cyclohexyl methyl pentanone.

Science.gov (United States)

Scognamiglio, J; Letizia, C S; Api, A M

2013-12-01

A toxicologic and dermatologic review of cyclohexyl methyl pentanone when used as a fragrance ingredient is presented. Cyclohexyl methyl pentanone is a member of the fragrance structural group Alkyl Cyclic Ketones. These fragrances can be described as being composed of an alkyl, R1, and various substituted and bicyclic saturated or unsaturated cyclic hydrocarbons, R2, in which one of the rings may include up to 12 carbons. Alternatively, R2 may be a carbon bridge of C2-C4 carbon chain length between the ketone and cyclic hydrocarbon. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for cyclohexyl methyl pentanone were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, skin sensitization, phototoxicity, photoallergy, and genotoxicity data. A safety assessment of the entire Alkyl Cyclic Ketones will be published simultaneously with this document; please refer to Belsito et al. (Belsito, D., Bickers, D., Bruze, M., Calow, P., Dagli, M., Fryer, A.D., Greim, H., Miyachi, Y., Saurat, J.H., Sipes, I.G., 2013. A toxicologic and dermatologic assessment of alkyl cyclic ketones when used as fragrance ingredients (submitted for publication).) for an overall assessment of the safe use of this material and all Alkyl Cyclic Ketones in fragrances. Copyright © 2013. Published by Elsevier Ltd.

Synthesis and spectral characterization of mono- and binuclear copper(II) complexes derived from 2-benzoylpyridine-N4-methyl-3-thiosemicarbazone: Crystal structure of a novel sulfur bridged copper(II) box-dimer

Science.gov (United States)

Jayakumar, K.; Sithambaresan, M.; Aiswarya, N.; Kurup, M. R. Prathapachandra

2015-03-01

Mononuclear and binuclear copper(II) complexes of 2-benzoylpyridine-N4-methyl thiosemicarbazone (HL) were prepared and characterized by a variety of spectroscopic techniques. Structural evidence for the novel sulfur bridged copper(II) iodo binuclear complex is obtained by single crystal X-ray diffraction analysis. The complex [Cu2L2I2], a non-centrosymmetric box dimer, crystallizes in monoclinic C2/c space group and it was found to have distorted square pyramidal geometry (Addison parameter, τ = 0.238) with the square basal plane occupied by the thiosemicarbazone moiety and iodine atom whereas the sulfur atom from the other coordinated thiosemicarbazone moiety occupies the apical position. This is the first crystallographically studied system having non-centrosymmetrical entities bridged via thiolate S atoms with Cu(II)sbnd I bond. The tridentate thiosemicarbazone coordinates in mono deprotonated thionic tautomeric form in all complexes except in sulfato complex, [Cu(HL)(SO4)]·H2O (1) where it binds to the metal centre in neutral form. The magnetic moment values and the EPR spectral studies reflect the binuclearity of some of the complexes. The spin Hamiltonian and bonding parameters are calculated based on EPR studies. In all the complexes g|| > g⊥ > 2.0023 and the g values in frozen DMF are consistent with the dx2-y2 ground state. The thermal stabilities of some of the complexes were also determined.

Clostridium beijerinckii mutant obtained atmospheric pressure glow discharge generates enhanced electricity in a microbial fuel cell.

Science.gov (United States)

Liu, Jun; Guo, Ting; Wang, Dong; Ying, Hanjie

2015-01-01

A Clostridium beijerinckii mutant M13 was derived from C. beijerinckii NCIMB 8052 by atmospheric pressure glow discharge. C. beijerinckii M13 generated a maximum output power density of 79.2 mW m(-2) and a maximum output voltage of 230 mV in a microbial fuel cell containing 1 g glucose l(-1) as carbon source and 0.15 g methyl viologen l(-1) as an electron carrier.

The Akashi Kaikyo Bridge and the Storebælt Bridge

DEFF Research Database (Denmark)

Gimsing, Niels Jørgen

1999-01-01

With the completion of the Akashi Kaikyo Bridge and the Storebælt East Bridge the development of the suspension bridge technology in the 20th century has manifested itself in two impressive structures. With the present echnology may bridges of similar (and also more modest) dimensions...... will undoubtedly be built far into the next century. For bridges going beyond the spans of existing bridges it is, however, likely that new concepts will be developed....

N-Methyl Inversion and Accurate Equilibrium Structures in Alkaloids: Pseudopelletierine.

Science.gov (United States)

Vallejo-López, Montserrat; Écija, Patricia; Vogt, Natalja; Demaison, Jean; Lesarri, Alberto; Basterretxea, Francisco J; Cocinero, Emilio J

2017-11-21

A rotational spectroscopy investigation has resolved the conformational equilibrium and structural properties of the alkaloid pseudopelletierine. Two different conformers, which originate from inversion of the N-methyl group from an axial to an equatorial position, have been unambiguously identified in the gas phase, and nine independent isotopologues have been recorded by Fourier-transform microwave spectroscopy in a jet expansion. Both conformers share a chair-chair configuration of the two bridged six-membered rings. The conformational equilibrium is displaced towards the axial form, with a relative population in the supersonic jet of N axial /N equatorial ≈2/1. An accurate equilibrium structure has been determined by using the semiexperimental mixed-estimation method and alternatively computed by quantum-chemical methods up to the coupled-cluster level of theory. A comparison with the N-methyl inversion equilibria in related tropanes is also presented. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bridge Management Systems

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

In this paper bridge management systems are discussed with special emphasis on management systems for reinforced concrete bridges. Management systems for prestressed concrete bridges, steel bridges, or composite bridges can be developed in a similar way....

Synthesis and spectral characterization of mono- and binuclear copper(II) complexes derived from 2-benzoylpyridine-N⁴-methyl-3-thiosemicarbazone: crystal structure of a novel sulfur bridged copper(II) box-dimer.

Science.gov (United States)

Jayakumar, K; Sithambaresan, M; Aiswarya, N; Kurup, M R Prathapachandra

2015-03-15

Mononuclear and binuclear copper(II) complexes of 2-benzoylpyridine-N(4)-methyl thiosemicarbazone (HL) were prepared and characterized by a variety of spectroscopic techniques. Structural evidence for the novel sulfur bridged copper(II) iodo binuclear complex is obtained by single crystal X-ray diffraction analysis. The complex [Cu2L2I2], a non-centrosymmetric box dimer, crystallizes in monoclinic C2/c space group and it was found to have distorted square pyramidal geometry (Addison parameter, τ=0.238) with the square basal plane occupied by the thiosemicarbazone moiety and iodine atom whereas the sulfur atom from the other coordinated thiosemicarbazone moiety occupies the apical position. This is the first crystallographically studied system having non-centrosymmetrical entities bridged via thiolate S atoms with Cu(II)I bond. The tridentate thiosemicarbazone coordinates in mono deprotonated thionic tautomeric form in all complexes except in sulfato complex, [Cu(HL)(SO4)]·H2O (1) where it binds to the metal centre in neutral form. The magnetic moment values and the EPR spectral studies reflect the binuclearity of some of the complexes. The spin Hamiltonian and bonding parameters are calculated based on EPR studies. In all the complexes g||>g⊥>2.0023 and the g values in frozen DMF are consistent with the d(x2-y2) ground state. The thermal stabilities of some of the complexes were also determined. Copyright © 2014 Elsevier B.V. All rights reserved.

Railroad Bridges

Data.gov (United States)

Department of Homeland Security — Bridges-Rail in the United States According to The National Bridge Inspection Standards published in the Code of Federal Regulations (23 CFR 650.3), a bridge isA...

Implementation of Bridge Management System on Interurban Bridge in Maluku Province

Directory of Open Access Journals (Sweden)

Erwin Marasabessy

2015-05-01

Full Text Available Bridges as transport infrastructures play a vital role in smoothing traffic flows. The success of a bridge in playing its role and serving its function depends on its management. The Directorate General of Highways of the Ministry of Public Work has used a system to manage bridges known as the Bridge Management System (BMS. The system allows a systematic plan and provides a uniform procedure for all bridge operation activities on the national and provincial level. Data from Implementation Agency of National Inter-Urban Roads of Area IX, Northern Maluku in 2011 indicates that the total length of national roads in Maluku Province is 15,238.01 M, with a total of 562 bridges. In Ambon Island, especially, there are 52 bridges totaling 1,176.25 m in length. The study was conducted at several inter-urban bridges in Maluku Province of Ambon Island: Wai Batu Merah, Wai Ruhu, Wai Lawa, Wai Yari and Wai Tua bridges. Assessment of bridge structure conditions was conducted visually to determine the conditions of the existing bridges comprehensively by referring to the Bridge Management System (BMS complemented with a computer-based Bridge Management Information System (BMIS. Condition scores for the five bridges—Wai Batu Merah, Wai Ruhu, Wai Lawa, Wai Yari, and Wai Tua, according to Bridge Management System, are 2, 1, 2, 1, and 2 respectively. The scores of the five bridges indicate that their physical condition can be categorized as good or with minor defects. Based on technical screening, the proposed treatment for Wai Batu Merah, Wai Ruhu, Wai Lawa, dan Wai Tua bridges is the rehabilitation of their sub-elements. As for the Wai Yari Bridge, the treatment will be maintained regularly. The defect repair costs are IDR 149,138,238.00, IDR 81,048,000.00, IDR 174,579,106.10, IDR 79,233,324.01 and IDR 238,323,258.60 for Wai Batu, Wai Ruhu, Wai Lawa, Wai Yari, and Wai Tua Bridges, respectively.

Long-term bridge performance high priority bridge performance issues.

Science.gov (United States)

2014-10-01

Bridge performance is a multifaceted issue involving performance of materials and protective systems, : performance of individual components of the bridge, and performance of the structural system as a whole. The : Long-Term Bridge Performance (LTBP)...

Identification of Differentially Methylated Sites with Weak Methylation Effects

Directory of Open Access Journals (Sweden)

Hong Tran

2018-02-01

Full Text Available Deoxyribonucleic acid (DNA methylation is an epigenetic alteration crucial for regulating stress responses. Identifying large-scale DNA methylation at single nucleotide resolution is made possible by whole genome bisulfite sequencing. An essential task following the generation of bisulfite sequencing data is to detect differentially methylated cytosines (DMCs among treatments. Most statistical methods for DMC detection do not consider the dependency of methylation patterns across the genome, thus possibly inflating type I error. Furthermore, small sample sizes and weak methylation effects among different phenotype categories make it difficult for these statistical methods to accurately detect DMCs. To address these issues, the wavelet-based functional mixed model (WFMM was introduced to detect DMCs. To further examine the performance of WFMM in detecting weak differential methylation events, we used both simulated and empirical data and compare WFMM performance to a popular DMC detection tool methylKit. Analyses of simulated data that replicated the effects of the herbicide glyphosate on DNA methylation in Arabidopsis thaliana show that WFMM results in higher sensitivity and specificity in detecting DMCs compared to methylKit, especially when the methylation differences among phenotype groups are small. Moreover, the performance of WFMM is robust with respect to small sample sizes, making it particularly attractive considering the current high costs of bisulfite sequencing. Analysis of empirical Arabidopsis thaliana data under varying glyphosate dosages, and the analysis of monozygotic (MZ twins who have different pain sensitivities—both datasets have weak methylation effects of <1%—show that WFMM can identify more relevant DMCs related to the phenotype of interest than methylKit. Differentially methylated regions (DMRs are genomic regions with different DNA methylation status across biological samples. DMRs and DMCs are essentially the same

Helquats, helical extended diquats, as fast electron transfer systems

Czech Academy of Sciences Publication Activity Database

Pospíšil, Lubomír; Teplý, Filip; Gál, Miroslav; Adriaenssens, Louis; Horáček, Michal; Severa, Lukáš

2010-01-01

Roč. 12, č. 7 (2010), s. 1550-1556 ISSN 1463-9076 R&D Projects: GA ČR GA203/09/0705; GA ČR GP203/09/P502; GA MŠk ME09114; GA MŠk OC 140 Institutional research plan: CEZ:AV0Z40400503; CEZ:AV0Z40550506 Keywords : reversible redox systems * self-exchange kinetics * methyl viologen Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.454, year: 2010

47 CFR 80.163 - Operator requirements of the Bridge-to-Bridge Act.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Operator requirements of the Bridge-to-Bridge... Requirements § 80.163 Operator requirements of the Bridge-to-Bridge Act. Each ship subject to the Bridge-to-Bridge Act must have on board a radio operator who holds a restricted radiotelephone operator permit or...

Bridge health monitoring metrics : updating the bridge deficiency algorithm.

Science.gov (United States)

2009-10-01

As part of its bridge management system, the Alabama Department of Transportation (ALDOT) must decide how best to spend its bridge replacement funds. In making these decisions, ALDOT managers currently use a deficiency algorithm to rank bridges that ...

47 CFR 80.309 - Watch required by the Bridge-to-Bridge Act.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Watch required by the Bridge-to-Bridge Act. 80... Safety Watches § 80.309 Watch required by the Bridge-to-Bridge Act. In addition to the watch requirement contained in § 80.148, all vessels subject to the Bridge-to-Bridge Act must keep a watch on the designated...

Field performance of timber bridges. 7, Connell Lake stress-laminated deck bridge

Science.gov (United States)

L. E. Hislop; M. A. Ritter

The Connell Lake bridge was constructed in early 1991 on the Tongass National Forest, Alaska, as a demonstration bridge under the Timber Bridge Initiative. The bridge is a stress-laminated deck structure with an approximate 36-ft length and 18-ft width and is the first known stress-laminated timber bridge constructed in Alaska. Performance of the bridge was monitored...

Track-Bridge Longitudinal Interaction of Continuous Welded Rails on Arch Bridge

Directory of Open Access Journals (Sweden)

Rong Chen

2013-01-01

Full Text Available Taking arch bridges, including deck, half-through, and through arch bridges (short for DAB, HTAB, and TAB as examples, mechanics analysis models of longitudinal interaction between continuously welded rails (short for CWRs and arch bridges are established. Based on the finite element method (FEM, the longitudinal interaction calculation software of CWR on arch bridges has been developed. Focusing on an HTAB, the tension, compression, and deflection conditions are calculated and analyzed. The results show that the mechanics analysis models of three types of arch bridges can truly reflect the real state of the structure; the calculation software can be used for systematic research of the CWR on arch bridge; as for HTAB, temperature difference of arch rib has a small effect on rail tension/compression, and arch bridge can be simplified as a continuous beam for rail tension/compression additional force calculation; in calculation of deflection conditions of HTAB, it is suggested that train loads are arranged on half span and full span and take the direction of load entering bridge into account. Additionally, the deflection additional force variation of CFST basket handle arch bridge is different from that of ordinary bridge.

Whole-genome methylation caller designed for methyl- DNA ...

African Journals Online (AJOL)

etchie

2013-02-20

Feb 20, 2013 ... Our method uses a single-CpG-resolution, whole-genome methylation ... Key words: Methyl-DNA immunoprecipitation, next-generation sequencing, ...... methylation is prevalent in embryonic stem cells andmaybe mediated.

Electron transfer between a zinc porphyrin photo-sensitized in the visible, and various acceptors, in aqueous and micellar solutions

International Nuclear Information System (INIS)

Le Roux, Dominique

1983-01-01

This research thesis addresses the study of reactions occurring during the transformation of solar energy in chemical energy, and more precisely the search for photochemical systems allowing the dissociation of water into hydrogen and oxygen. In this study on water photolysis, the author chose to use a porphyrin soluble in water, the zinc tetra-meta-N-methylpyridinium porphyrin, as one of its isomer provided a good efficiency in hydrogen formation. Before reporting the study of electron photo-transfer, the author reports the study of photo-physical and photochemical properties of this porphyrin. Then, in the case of a well known electron acceptor (methyl viologen), he studied the influence of Coulomb effects on the kinetics of direct electron transfer, and on the kinetics of recombination of formed species. He also studied the influence of organised systems (cationic micelles) on these reactions when using a viologen with long chains. He finally reports the study of reactions of the triplet state of this porphyrin with metallic complexes

Identification of endometrial cancer methylation features using combined methylation analysis methods.

Directory of Open Access Journals (Sweden)

Michael P Trimarchi

Full Text Available DNA methylation is a stable epigenetic mark that is frequently altered in tumors. DNA methylation features are attractive biomarkers for disease states given the stability of DNA methylation in living cells and in biologic specimens typically available for analysis. Widespread accumulation of methylation in regulatory elements in some cancers (specifically the CpG island methylator phenotype, CIMP can play an important role in tumorigenesis. High resolution assessment of CIMP for the entire genome, however, remains cost prohibitive and requires quantities of DNA not available for many tissue samples of interest. Genome-wide scans of methylation have been undertaken for large numbers of tumors, and higher resolution analyses for a limited number of cancer specimens. Methods for analyzing such large datasets and integrating findings from different studies continue to evolve. An approach for comparison of findings from a genome-wide assessment of the methylated component of tumor DNA and more widely applied methylation scans was developed.Methylomes for 76 primary endometrial cancer and 12 normal endometrial samples were generated using methylated fragment capture and second generation sequencing, MethylCap-seq. Publically available Infinium HumanMethylation 450 data from The Cancer Genome Atlas (TCGA were compared to MethylCap-seq data.Analysis of methylation in promoter CpG islands (CGIs identified a subset of tumors with a methylator phenotype. We used a two-stage approach to develop a 13-region methylation signature associated with a "hypermethylator state." High level methylation for the 13-region methylation signatures was associated with mismatch repair deficiency, high mutation rate, and low somatic copy number alteration in the TCGA test set. In addition, the signature devised showed good agreement with previously described methylation clusters devised by TCGA.We identified a methylation signature for a "hypermethylator phenotype" in

Bridges

NARCIS (Netherlands)

Zant, W.

2017-01-01

We estimate to what extent bridges in Mozambique lead to transport cost reductions and attribute these reductions to key determinants, in particular road distance, road quality and crossing borders. For identification we exploit the introduction of a road bridge over the Zambezi river, in August

Methylation of food commodities during fumigation with methyl bromide

International Nuclear Information System (INIS)

Starratt, A.N.; Bond, E.J.

1990-01-01

Sites of methylation in several commodities (wheat, oatmeal, peanuts, almonds, apples, oranges, maize, alfalfa and potatoes) during fumigation with 14 C-methyl bromide were studied. Differences were observed in levels of the major volatiles: methanol, dimethyl sulphide and methyl mercaptan, products of O- and S-methylation, resulting from treatment of the fumigated materials with 1N sodium hydroxide. In studies of maize and wheat, histidine was the amino acid which underwent the highest level of N-methylation. (author). 24 refs, 3 tabs

Field performance of timber bridges. 4, Graves Crossing stress-laminated deck bridge

Science.gov (United States)

J. P. Wacker; M. A. Ritter

The Graves Crossing bridge was constructed October 1991 in Antrim County, Michigan, as part of the demonstration timber bridge program sponsored by the USDA Forest Service. The bridge is a two-span continuous, stress-laminated deck superstructure and it is 36-ft long and 26-ft wide. The bridge is one of the first stress-laminated deck bridges to be built of sawn lumber...

Myocardial Bridging

Directory of Open Access Journals (Sweden)

Shi-Min Yuan

2016-02-01

Full Text Available Abstract Myocardial bridging is rare. Myocardial bridges are most commonly localized in the middle segment of the left anterior descending coronary artery. The anatomic features of the bridges vary significantly. Alterations of the endothelial morphology and the vasoactive agents impact on the progression of atherosclerosis of myocardial bridging. Patients may present with chest pain, myocardial infarction, arrhythmia and even sudden death. Patients who respond poorly to the medical treatment with β-blockers warrant a surgical intervention. Myotomy is a preferred surgical procedure for the symptomatic patients. Coronary stent deployment has been in limited use due to the unsatisfactory long-term results.

The hepatic bridge.

Science.gov (United States)

Sugarbaker, Paul H

2018-07-01

The hepatic bridge forms a tunnel of liver parenchyma that may obscure peritoneal metastases associated with the round ligament. Visualization and then resection of nodules associated with this structure is necessary. The incidence of a hepatic bridge and the extent that it covered the round ligament was determined in consecutive patients. Extent of coverage of the round ligament by the hepatic bridge was determined: Class 1 indicates up to one-third of the round ligament obscured, Class 2 up to two-thirds and Class 3 more than two-thirds. In 102 patients in whom the round ligament of the liver could be completely visualized, 50 had a hepatic bridge. Class 1 was 22 (44%) of the bridges, Class 2 was 16 (32%) and Class 3 was 12 (24%). A hepatic bridge was more frequently present in 28 of 45 male patients (62%) vs. 22 of 57 female patients (38%). Approximately one-half of our patients having cytoreductive surgery for peritoneal metastases were observed to have a hepatic bridge. Up to 56% of these patients have Class 2 or 3 hepatic bridge and may require division of the hepatic bridge to completely visualize the contents of the tunnel created by this structure. Copyright © 2018 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

Bridge resource program.

Science.gov (United States)

2013-09-01

The mission of Rutgers Universitys Center for Advanced Infrastructure and Transportation (CAIT) Bridge Resource Program (BRP) is to provide bridge engineering support to the New Jersey Department of Transportation (NJDOT)s Bridge Engineering an...

Bridged graphite oxide materials

Science.gov (United States)

Herrera-Alonso, Margarita (Inventor); McAllister, Michael J. (Inventor); Aksay, Ilhan A. (Inventor); Prud'homme, Robert K. (Inventor)

2010-01-01

Bridged graphite oxide material comprising graphite sheets bridged by at least one diamine bridging group. The bridged graphite oxide material may be incorporated in polymer composites or used in adsorption media.

Laboratory and field testing of an accelerated bridge construction demonstration bridge : US Highway 6 bridge over Keg Creek.

Science.gov (United States)

2013-04-01

The US Highway 6 Bridge over Keg Creek outside of Council Bluffs, Iowa is a demonstration bridge site chosen to put into practice : newly-developed Accelerated Bridge Construction (ABC) concepts. One of these new concepts is the use of prefabricated ...

Guardrails for Use on Historic Bridges: Volume 2—Bridge Deck Overhang Design

OpenAIRE

Frosch, Robert J.; Morel, Adam J.

2016-01-01

Bridges that are designated historic present a special challenge to bridge engineers whenever rehabilitation work or improvements are made to the bridges. Federal and state laws protect historically significant bridges, and railings on these bridges can be subject to protection because of the role they play in aesthetics. Unfortunately, original railings on historic bridges do not typically meet current crash-test requirements and typically do not meet current standards for railing height and...

MethylMix 2.0: an R package for identifying DNA methylation genes.

Science.gov (United States)

Cedoz, Pierre-Louis; Prunello, Marcos; Brennan, Kevin; Gevaert, Olivier

2018-04-14

DNA methylation is an important mechanism regulating gene transcription, and its role in carcinogenesis has been extensively studied. Hyper and hypomethylation of genes is a major mechanism of gene expression deregulation in a wide range of diseases. At the same time, high-throughput DNA methylation assays have been developed generating vast amounts of genome wide DNA methylation measurements. We developed MethylMix, an algorithm implemented in R to identify disease specific hyper and hypomethylated genes. Here we present a new version of MethylMix that automates the construction of DNA-methylation and gene expression datasets from The Cancer Genome Atlas (TCGA). More precisely, MethylMix 2.0 incorporates two major updates: the automated downloading of DNA methylation and gene expression datasets from TCGA and the automated preprocessing of such datasets: value imputation, batch correction and CpG sites clustering within each gene. The resulting datasets can subsequently be analyzed with MethylMix to identify transcriptionally predictive methylation states. We show that the Differential Methylation Values created by MethylMix can be used for cancer subtyping. olivier.gevaert@stanford.edu. https://bioconductor.org/packages/release/bioc/manuals/MethylMix/man/MethylMix.pdf. MethylMix 2.0 was implemented as an R package and is available in bioconductor.

Global DNA methylation analysis using methyl-sensitive amplification polymorphism (MSAP).

Science.gov (United States)

Yaish, Mahmoud W; Peng, Mingsheng; Rothstein, Steven J

2014-01-01

DNA methylation is a crucial epigenetic process which helps control gene transcription activity in eukaryotes. Information regarding the methylation status of a regulatory sequence of a particular gene provides important knowledge of this transcriptional control. DNA methylation can be detected using several methods, including sodium bisulfite sequencing and restriction digestion using methylation-sensitive endonucleases. Methyl-Sensitive Amplification Polymorphism (MSAP) is a technique used to study the global DNA methylation status of an organism and hence to distinguish between two individuals based on the DNA methylation status determined by the differential digestion pattern. Therefore, this technique is a useful method for DNA methylation mapping and positional cloning of differentially methylated genes. In this technique, genomic DNA is first digested with a methylation-sensitive restriction enzyme such as HpaII, and then the DNA fragments are ligated to adaptors in order to facilitate their amplification. Digestion using a methylation-insensitive isoschizomer of HpaII, MspI is used in a parallel digestion reaction as a loading control in the experiment. Subsequently, these fragments are selectively amplified by fluorescently labeled primers. PCR products from different individuals are compared, and once an interesting polymorphic locus is recognized, the desired DNA fragment can be isolated from a denaturing polyacrylamide gel, sequenced and identified based on DNA sequence similarity to other sequences available in the database. We will use analysis of met1, ddm1, and atmbd9 mutants and wild-type plants treated with a cytidine analogue, 5-azaC, or zebularine to demonstrate how to assess the genetic modulation of DNA methylation in Arabidopsis. It should be noted that despite the fact that MSAP is a reliable technique used to fish for polymorphic methylated loci, its power is limited to the restriction recognition sites of the enzymes used in the genomic

Dynamic assessment of bridge deck performance considering realistic bridge-traffic interaction

Science.gov (United States)

2017-09-01

Concrete bridge decks are directly exposed to daily traffic loads and may experience some surface cracking caused by excessive stress or fatigue accumulation, which requires repair or replacement. Among typical bridges in North America, bridge decks ...

Cable Supported Bridges

DEFF Research Database (Denmark)

Gimsing, Niels Jørgen

Cable supported bridges in the form of suspension bridges and cable-stayed bridges are distinguished by their ability to overcome large spans.The book concentrates on the synthesis of cable supported bridges, covering both design and construction aspects. The analytical part covers simple methods...... to quantify the different structural configurations and allows a preliminary optimization of the main structure.Included are the most recent advances in structural design, corrosion protection of cables, aerodynamic safety, and erection procedures....

Bridge Programs in Illinois: Results of the 2010 Illinois Bridge Status Survey

Science.gov (United States)

Taylor, J. L.; Harmon, T.

2010-01-01

This report provides a summary of major results of the Illinois Bridge Status Survey, administered online between April and June 2010. The purpose of the survey was to understand the extent to which bridge programs are being implemented in Illinois, as well as to build an online directory of bridge programs. Bridge programs are an emerging…

Field performance of timber bridges. 6, Hoffman Run stress-laminated deck bridge

Science.gov (United States)

M. A. Ritter; P. D. Hilbrich Lee; G. J. Porter

The Hoffman Run bridge, located just outside Dahoga, Pennsylvania, was constructed in October 1990. The bridge is a simple-span, single-lane, stress-laminated deck superstructure that is approximately 26 ft long and 16 ft wide. It is the second stress-laminated timber bridge to be constructed of hardwood lumber in Pennsylvania. The performance of the bridge was...

Drill pipe bridge plug

International Nuclear Information System (INIS)

Winslow, D.W.; Brisco, D.P.

1991-01-01

This patent describes a method of stopping flow of fluid up through a pipe bore of a pipe string in a well. It comprises: lowering a bridge plug apparatus on a work string into the pipe string to a position where the pipe bore is to be closed; communicating the pipe bore below a packer of the bridge plug apparatus through the bridge plug apparatus with a low pressure zone above the packer to permit the fluid to flow up through the bridge plug apparatus; engaging the bridge plug apparatus with an internal upset of the pipe string; while the fluid is flowing up through the bridge plug apparatus, pulling upward on the work string and the bridge plug apparatus and thereby sealing the packer against the pipe bore; isolating the pipe bore below the packer from the low pressure zone above the packer and thereby stopping flow of the fluid up through the pipe bore; disconnecting the work string from the bridge plug apparatus; and maintaining the bridge plug apparatus in engagement with the internal upset and sealed against the pipe bore due to an upward pressure differential applied to the bridge plug apparatus by the fluid contained therebelow

Systemic effects of chronically administered methyl prednisolonate and methyl 17-deoxyprednisolonate.

Science.gov (United States)

Olejniczak, E; Lee, H J

1984-06-01

The systemic activities of methyl prednisolonate and methyl 17-deoxyprednisolonate (1) were studied in rats. Methyl 17-deoxyprednisolonate produced significant changes in the amount of sodium ion (decreased) and potassium ion (increased) in urine; however, methyl prednisolonate had no effect on electrolyte balance. Both methyl prednisolonate and methyl 17-deoxyprednisolonate had no effect on liver glycogen content, plasma corticosterone level and relative adrenal weight. In contrast, the parent compound prednisolone caused a significant decrease in liver glycogen content, plasma corticosterone level and relative adrenal weight.

Bridging Anticoagulation

Science.gov (United States)

... clinical centers in the United States, Canada, and Brazil. A more detailed description of the study is ... Your Personal Message Send Message Share on Social Media Bridging Anticoagulation The BRIDGE Study Investigators Circulation. 2012; ...

Bridging the Gap

DEFF Research Database (Denmark)

Kramer Overgaard, Majken; Broeng, Jes; Jensen, Monika Luniewska

Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures.......Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures....

Long Span Bridges in Scandinavia

DEFF Research Database (Denmark)

Gimsing, Niels Jørgen

1998-01-01

The first Scandinavian bridge with a span of more than 500 m was the Lillebælt Suspension Bridge opened to traffic in 1970.Art the end of the 20th century the longest span of any European bridge is found in the Storebælt East Bridge with a main span of 1624 m. Also the third longest span in Europe...... is found in Scandinavia - the 1210 m span of the Höga Kusten Bridge in Sweden.The Kvarnsund Bridge in Norway was at the completion in 1991 the longest cable-stayed bridge in the world, and the span of 530 m is still thge longest for cable-stayed bridges in concrete. The Øresund Bridge with its sapn of 490...

trans-Methylpyridine cyclen versus cross-bridged trans-methylpyridine cyclen. Synthesis, acid-base and metal complexation studies (metal = Co2+, Cu2+, and Zn2+).

Science.gov (United States)

Bernier, Nicolas; Costa, Judite; Delgado, Rita; Félix, Vítor; Royal, Guy; Tripier, Raphaël

2011-05-07

The synthesis of the cross-bridged cyclen CRpy(2) {4,10-bis((pyridin-2-yl)methyl)-1,4,7,10-tetraazabicyclo[5.5.2]tetradecane}, a constrained analogue of the previously described trans-methylpyridine cyclen Cpy(2) is reported. The additional ethylene bridge confers to CRpy(2) proton-sponge type behaviour which was explored by NMR and potentiometric studies. Transition metal complexes have been synthesized (by complexation of both ligands with Co(2+), Cu(2+) and Zn(2+)) and characterized in solution and in the solid state. The single crystal X-ray structures of [CoCpy(2)](2+), [CuCpy(2)](2+) and [ZnCpy(2)](2+) complexes were determined. Stability constants of the complexes, including those of the cross-bridged derivative, were determined using potentiometric titration data and the kinetic inertness of the [CuCRpy(2)](2+) complex in an acidic medium (half-life values) was evaluated by spectrophotometry. The pre-organized structure of the cross-bridged ligand imposes an additional strain for the complexation leading to complexes with smaller thermodynamic stability in comparison with the related non-bridged ligand. The electrochemical study involving cyclic voltammetry underlines the importance of the ethylene cross-bridge on the redox properties of the transition metal complexes.

Integral Abutment and Jointless Bridges

Directory of Open Access Journals (Sweden)

Cristian-Claudiu Comisu

2005-01-01

Full Text Available Integral bridges, or integral abutment and jointless bridges, as they are more commonly known in the USA, are constructed without any movement joints between spans or between spans and abutments. Typically these bridges have stub-type abutments supported on piles and continuous bridge deck from one embankment to the other. Foundations are usually designed to be small and flexible to facilitate horizontal movement or rocking of the support. Integrally bridges are simple or multiple span ones that have their superstructure cast integrally with their substructure. The jointless bridges cost less to construct and require less maintenance then equivalent bridges with expansion joints. Integral bridges present a challenge for load distribution calculations because the bridge deck, piers, abutments, embankments and soil must all be considered as single compliant system. This paper presents some of the important features of integral abutment and jointless bridge design and some guidelines to achieve improved design. The goal of this paper is to enhance the awareness among the engineering community to use integral abutment and jointless bridges in Romania.

Bridge deterioration models to support Indiana's bridge management system.

Science.gov (United States)

2016-02-01

An effective bridge management system that is equipped with reliable deterioration models enables agency engineers to carry out : monitoring and long-term programming of bridge repair actions. At the project level, deterioration models help the agenc...

Automatic Bridge Control System

OpenAIRE

M. Niraimathi; S.Sivakumar; R.Vigneshwaran; R.Vinothkumar; P.Babu

2012-01-01

Bridge vibration control is an important issue whose purpose is to extend the structural service life of bridges. Normally, the bridge is modeled as an elastic beam or plate subject to a moving vehicle. However, the moving truck on a bridge is a complicated problem that must still be researched. In this paper, wepropose a new method, to overcome the huge load in the bridge a load cell is used at the entry which will monitor the load continuously at both ends. To escape from the heavy water fl...

Ultrafast static and diffusion-controlled electron transfer at Ag 29 nanocluster/molecular acceptor interfaces

KAUST Repository

Aly, Shawkat Mohammede; AbdulHalim, Lina G.; Besong, Tabot M.D.; Soldan, Giada; Bakr, Osman; Mohammed, Omar F.

2015-01-01

Efficient absorption of visible light and a long-lived excited state lifetime of silver nanoclusters (Ag29 NCs) are integral properties for these new clusters to serve as light-harvesting materials. Upon optical excitation, electron injection at Ag29 NC/methyl viologen (MV2+) interfaces is very efficient and ultrafast. Interestingly, our femto- and nanosecond time-resolved results demonstrate clearly that both dynamic and static electron transfer mechanisms are involved in photoluminescence quenching of Ag29 NCs. © 2016 The Royal Society of Chemistry.

Ultrafast static and diffusion-controlled electron transfer at Ag 29 nanocluster/molecular acceptor interfaces

KAUST Repository

Aly, Shawkat Mohammede

2015-10-29

Efficient absorption of visible light and a long-lived excited state lifetime of silver nanoclusters (Ag29 NCs) are integral properties for these new clusters to serve as light-harvesting materials. Upon optical excitation, electron injection at Ag29 NC/methyl viologen (MV2+) interfaces is very efficient and ultrafast. Interestingly, our femto- and nanosecond time-resolved results demonstrate clearly that both dynamic and static electron transfer mechanisms are involved in photoluminescence quenching of Ag29 NCs. © 2016 The Royal Society of Chemistry.

Existing Steel Railway Bridges Evaluation

Science.gov (United States)

Vičan, Josef; Gocál, Jozef; Odrobiňák, Jaroslav; Koteš, Peter

2016-12-01

The article describes general principles and basis of evaluation of existing railway bridges based on the concept of load-carrying capacity determination. Compared to the design of a new bridge, the modified reliability level for existing bridges evaluation should be considered due to implementation of the additional data related to bridge condition and behaviour obtained from regular inspections. Based on those data respecting the bridge remaining lifetime, a modification of partial safety factors for actions and materials could be respected in the bridge evaluation process. A great attention is also paid to the specific problems of determination of load-caring capacity of steel railway bridges in service. Recommendation for global analysis and methodology for existing steel bridge superstructure load-carrying capacity determination are described too.

Isomerization and dissociation in competition: the two-component dissociation rates of methyl acetate ions

Science.gov (United States)

Mazyar, Oleg A.; Mayer, Paul M.; Baer, Tomas

1997-11-01

Threshold photoelectron-photoion coincidence (TPEPICO) spectroscopy has been used to investigate the unimolecular chemistry of metastable methyl acetate ions, CH3COOCH3.+. The rate of molecular ion fragmentation with the loss of CH3O. and CH2OH radicals as a function of ion internal energy was obtained from the coincidence data and used in conjunction with Rice-Ramsperger-Kassel-Markus and ab initio molecular orbital calculations to model the dissociation/isomerization mechanism of the methyl acetate ion (A). The data were found to be consistent with the mechanism involving a hydrogen-bridged complex CH3CO[middle dot][middle dot][middle dot]H[middle dot][middle dot][middle dot]OCH2.+(E) as the direct precursor of the observed fragments CH3CO+ and CH2OH.. The two-component decay rates were modeled with a three-well-two-product potential energy surface including the distonic ion CH3C(OH)OCH2.+(B) and enol isomer CH2C(OH)OCH3.+(C), which are formed from the methyl acetate ion by two consecutive [1,4]-hydrogen shifts. The 0 K heats of formation of isomers B and C as well as transition states TSAB, TSBC, and TSBE (relative to isomer A) were calculated from Rice-Ramsperger-Kassel-Markus (RRKM) theory.

Field performance of timber bridges. 5, Little Salmon Creek stress-laminated deck bridge

Science.gov (United States)

M. A. Ritter; J. A. Kainz; G. J. Porter

The Little Salmon Creek bridge was constructed in November 1988 on the Allegheny National Forest in Pennsylvania. The bridge is a simple span, single-lane, stress-laminated deck superstructure that is approximately 26-ft long and 16-ft wide. The bridge is unique in that it is the first known stress-laminated timber bridge to be constructed of hardwood lumber. The...

Field performance of timber bridges. 9, Big Erick`s stress-laminated deck bridge

Science.gov (United States)

J. A. Kainz; J. P. Wacker; M. Nelson

The Big Erickas bridge was constructed during September 1992 in Baraga County, Michigan. The bridge is 72 ft long, 16 ft wide, and consists of three simple spans: two stress-laminated deck approach spans and a stress-laminated box center span. The bridge is unique in that it is one of the first known stress-laminated timber bridge applications to use Eastern Hemlock...

Hydraulic modeling of flow impact on bridge structures: a case study on Citarum bridge

Science.gov (United States)

Siregar, R. I.

2018-02-01

Flood waves because of the rapid catchment response to high intense rainfall, breaches of flood defenses may induce huge impact forces on structures, causing structural damage or even failures. Overflowing stream that passes over the bridge, it means to discharge flood water level is smaller than the capacity of the river flow. In this study, the researches present the methodological approach of flood modeling on bridge structures. The amount of force that obtained because of the hydrostatic pressure received by the bridge at the time of the flood caused the bridge structure disrupted. This paper presents simulation of flow impact on bridge structures with some event flood conditions. Estimating the hydrostatic pressure developed new model components, to quantify the flow impact on structures. Flow parameters applied the model for analyzing, such as discharge, velocity, and water level or head that effect of bridge structures. The simulation will illustrate the capability of bridge structures with some event flood river and observe the behavior of the flow that occurred during the flood. Hydraulic flood modeling use HEC-RAS for simulation. This modeling will describe the impact on bridge structures. Based on the above modelling resulted, in 2008 has flood effect more than other years on the Citarum Bridge, because its flow overflow on the bridge.

DNA methylation analysis reveals distinct methylation signatures in pediatric germ cell tumors

International Nuclear Information System (INIS)

Amatruda, James F; Frazier, A Lindsay; Poynter, Jenny N; Ross, Julie A; Christensen, Brock; Fustino, Nicholas J; Chen, Kenneth S; Hooten, Anthony J; Nelson, Heather; Kuriger, Jacquelyn K; Rakheja, Dinesh

2013-01-01

Aberrant DNA methylation is a prominent feature of many cancers, and may be especially relevant in germ cell tumors (GCTs) due to the extensive epigenetic reprogramming that occurs in the germ line during normal development. We used the Illumina GoldenGate Cancer Methylation Panel to compare DNA methylation in the three main histologic subtypes of pediatric GCTs (germinoma, teratoma and yolk sac tumor (YST); N = 51) and used recursively partitioned mixture models (RPMM) to test associations between methylation pattern and tumor and demographic characteristics. We identified genes and pathways that were differentially methylated using generalized linear models and Ingenuity Pathway Analysis. We also measured global DNA methylation at LINE1 elements and evaluated methylation at selected imprinted loci using pyrosequencing. Methylation patterns differed by tumor histology, with 18/19 YSTs forming a distinct methylation class. Four pathways showed significant enrichment for YSTs, including a human embryonic stem cell pluripotency pathway. We identified 190 CpG loci with significant methylation differences in mature and immature teratomas (q < 0.05), including a number of CpGs in stem cell and pluripotency-related pathways. Both YST and germinoma showed significantly lower methylation at LINE1 elements compared with normal adjacent tissue while there was no difference between teratoma (mature and immature) and normal tissue. DNA methylation at imprinted loci differed significantly by tumor histology and location. Understanding methylation patterns may identify the developmental stage at which the GCT arose and the at-risk period when environmental exposures could be most harmful. Further, identification of relevant genetic pathways could lead to the development of new targets for therapy

Existing Steel Railway Bridges Evaluation

Directory of Open Access Journals (Sweden)

Vičan Josef

2016-12-01

Full Text Available The article describes general principles and basis of evaluation of existing railway bridges based on the concept of load-carrying capacity determination. Compared to the design of a new bridge, the modified reliability level for existing bridges evaluation should be considered due to implementation of the additional data related to bridge condition and behaviour obtained from regular inspections. Based on those data respecting the bridge remaining lifetime, a modification of partial safety factors for actions and materials could be respected in the bridge evaluation process. A great attention is also paid to the specific problems of determination of load-caring capacity of steel railway bridges in service. Recommendation for global analysis and methodology for existing steel bridge superstructure load-carrying capacity determination are described too.

Cleavage of phosphorothioated DNA and methylated DNA by the type IV restriction endonuclease ScoMcrA.

Directory of Open Access Journals (Sweden)

Guang Liu

2010-12-01

Full Text Available Many taxonomically diverse prokaryotes enzymatically modify their DNA by replacing a non-bridging oxygen with a sulfur atom at specific sequences. The biological implications of this DNA S-modification (phosphorothioation were unknown. We observed that simultaneous expression of the dndA-E gene cluster from Streptomyces lividans 66, which is responsible for the DNA S-modification, and the putative Streptomyces coelicolor A(32 Type IV methyl-dependent restriction endonuclease ScoA3McrA (Sco4631 leads to cell death in the same host. A His-tagged derivative of ScoA3McrA cleaved S-modified DNA and also Dcm-methylated DNA in vitro near the respective modification sites. Double-strand cleavage occurred 16-28 nucleotides away from the phosphorothioate links. DNase I footprinting demonstrated binding of ScoA3McrA to the Dcm methylation site, but no clear binding could be detected at the S-modified site under cleavage conditions. This is the first report of in vitro endonuclease activity of a McrA homologue and also the first demonstration of an enzyme that specifically cleaves S-modified DNA.

Light-weight aluminium bridges and bridge decks. An overview of recent applications

NARCIS (Netherlands)

Maljaars, J.; Soetens, F.; Kluyver, D. de

2008-01-01

The last decades have shown a large increase in the application of aluminium alloys for light-weight bridges. For bridge construction, aluminium alloys have some specific advantages, but also some points of attention. This paper deals with some recent projects of aluminium bridges, and for these

Modeling of the oxidation of methyl esters—Validation for methyl hexanoate, methyl heptanoate, and methyl decanoate in a jet-stirred reactor

Science.gov (United States)

Glaude, Pierre Alexandre; Herbinet, Olivier; Bax, Sarah; Biet, Joffrey; Warth, Valérie; Battin-Leclerc, Frédérique

2013-01-01

The modeling of the oxidation of methyl esters was investigated and the specific chemistry, which is due to the presence of the ester group in this class of molecules, is described. New reactions and rate parameters were defined and included in the software EXGAS for the automatic generation of kinetic mechanisms. Models generated with EXGAS were successfully validated against data from the literature (oxidation of methyl hexanoate and methyl heptanoate in a jet-stirred reactor) and a new set of experimental results for methyl decanoate. The oxidation of this last species was investigated in a jet-stirred reactor at temperatures from 500 to 1100 K, including the negative temperature coefficient region, under stoichiometric conditions, at a pressure of 1.06 bar and for a residence time of 1.5 s: more than 30 reaction products, including olefins, unsaturated esters, and cyclic ethers, were quantified and successfully simulated. Flow rate analysis showed that reactions pathways for the oxidation of methyl esters in the low-temperature range are similar to that of alkanes. PMID:23710076

Modeling of the oxidation of methyl esters-Validation for methyl hexanoate, methyl heptanoate, and methyl decanoate in a jet-stirred reactor.

Science.gov (United States)

Glaude, Pierre Alexandre; Herbinet, Olivier; Bax, Sarah; Biet, Joffrey; Warth, Valérie; Battin-Leclerc, Frédérique

2010-11-01

The modeling of the oxidation of methyl esters was investigated and the specific chemistry, which is due to the presence of the ester group in this class of molecules, is described. New reactions and rate parameters were defined and included in the software EXGAS for the automatic generation of kinetic mechanisms. Models generated with EXGAS were successfully validated against data from the literature (oxidation of methyl hexanoate and methyl heptanoate in a jet-stirred reactor) and a new set of experimental results for methyl decanoate. The oxidation of this last species was investigated in a jet-stirred reactor at temperatures from 500 to 1100 K, including the negative temperature coefficient region, under stoichiometric conditions, at a pressure of 1.06 bar and for a residence time of 1.5 s: more than 30 reaction products, including olefins, unsaturated esters, and cyclic ethers, were quantified and successfully simulated. Flow rate analysis showed that reactions pathways for the oxidation of methyl esters in the low-temperature range are similar to that of alkanes.

Development of bridge girder movement criteria for accelerated bridge construction.

Science.gov (United States)

2014-06-01

End diaphragms connect multiple girders to form a bridge superstructure system for effective resistance to earthquake loads. Concrete : girder bridges that include end diaphragms consistently proved to perform well during previous earthquake events. ...

Active Control of Suspension Bridges

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

In this paper some recent research on active control of very long suspension bridges, is presented. The presentation is based on research work at Aalborg University, Denmark. The active control system is based on movable flaps attached to the bridge girder. Wind load on bridges with or without...... flaps attached to the girder is briefly presented. A simple active control system is discussed. Results from wind tunnel experiments with a bridge section show that flaps can be used effectively to control bridge girder vibrations. Flutter conditions for suspension bridges with and without flaps...

Evaluation of electrode surface modification techniques for the development of chemical sensors

International Nuclear Information System (INIS)

Galiatsatos, C.

1988-01-01

This thesis covers several aspects of electrode surface modification techniques. The successful application of gamma-radiation to create polymer-coated electrodes, where the polymers can be ion exchangers and consequently of great analytical interest by themselves (such as the polymer poly(diallyl) dimethyl ammonium chloride) or where some other neutral polymers can function as convenient matrices for the introduction of biomolecules and/or other electrochemically interesting species is reported. This is demonstrated by using the neutral polymer poly(vinyl alcohol) (PVAL) as a matrix for immobilization of the enzyme glucose oxidase and the mediator methyl viologen. The effect of γ-radiation on PVAL is discussed, as well as swelling properties of the irradiated polymers and specific characteristics of the created chemical sensors. Results of an experiment where the various kinds of interactions between the ion-exchange polymer Nafion and some positively charged species are explored are reported, and a model system for competition (methyl viologen vs. ruthenium hexaamine) which increases significantly our understanding of the interaction is mentioned. The effect of γ-radiation on Nafion and its ion-exchange compabilities is discussed also. A system of conduction polymers primarily polypyrrole, used as a detector of electroinactive anions due to their doping-undergoing in the film is discussed. Preliminary results on a new method that involves chemical cross-linking of a triisocyane molecule with -OH containing polymers in the presence of enzymes are reported

Crystal structure of rubidium methyl-diazo-tate.

Science.gov (United States)

Grassl, Tobias; Korber, Nikolaus

2017-02-01

The title compound, Rb + ·H 3 CN 2 O - , has been crystallized in liquid ammonia as a reaction product of the reductive ammonolysis of the natural compound streptozocin. Elemental rubidium was used as reduction agent as it is soluble in liquid ammonia, forming a blue solution. Reductive bond cleavage in biogenic materials under kinetically controlled conditions offers a new approach to gain access to sustainably produced raw materials. The anion is nearly planar [dihedral angle O-N-N-C = -0.4 (2)°]. The Rb + cation has a coordination number of seven, and coordinates to five anions. One anion is bound via both its N atoms, one by both O and N, two anions are bound by only their O atoms, and the last is bound via the N atom adjacent to the methyl group. The diazo-tate anions are bridged by cations and do not exhibit any direct contacts with each other. The cations form corrugated layers that propagate in the (-101) plane.

Morphological aspects of myocardial bridges.

Science.gov (United States)

Lujinović, Almira; Kulenović, Amela; Kapur, Eldan; Gojak, Refet

2013-11-01

Although some myocardial bridges can be asymptomatic, their presence often causes coronary disease either through direct compression of the "tunnel" segment or through stimulation and accelerated development of atherosclerosis in the segment proximally to the myocardial bridge. The studied material contained 30 human hearts received from the Department of Anatomy. The hearts were preserved 3 to 5 days in 10% formalin solution. Thereafter, the fatty tissue was removed and arterial blood vessels prepared by careful dissection with special reference to the presence of the myocardial bridges. Length and thickness of the bridges were measured by the precise electronic caliper. The angle between the myocardial bridge fibre axis and other axis of the crossed blood vessel was measured by a goniometer. The presence of the bridges was confirmed in 53.33% of the researched material, most frequently (43.33%) above the anterior interventricular branch. The mean length of the bridges was 14.64 ± 9.03 mm and the mean thickness was 1.23 ± 1.32 mm. Myocardial bridge fibres pass over the descending blood vessel at the angle of 10-90 degrees. The results obtained on a limited sample suggest that the muscular index of myocardial bridge is the highest for bridges located on RIA, but that the difference is not significant in relation to bridges located on other branches. The results obtained suggest that bridges located on other branches, not only those on RIA, could have a great contractive power and, consequently, a great compressive force, which would be exerted on the wall of a crossed blood vessel.

Field performance of timber bridges. 17, Ciphers stress-laminated deck bridge

Science.gov (United States)

James P. Wacker; James A. Kainz; Michael A. Ritter

In September 1989, the Ciphers bridge was constructed within the Beltrami Island State Forest in Roseau County, Minnesota. The bridge superstructure is a two-span continuous stress-laminated deck that is approximately 12.19 m long, 5.49 m wide, and 305 mm deep (40 ft long, 18 ft wide, and 12 in. deep). The bridge is one of the first to utilize red pine sawn lumber for...

Remarks on crack-bridging concepts

International Nuclear Information System (INIS)

Bao, G.; Suo, Z.

1992-01-01

The article draws upon recent work by us and our colleagues on metal and ceramic matrix composites for high temperature engines. The central theme here is to deduce mechanical properties, such as toughness, strength and notch-ductility, from bridging laws that characterize inelastic processes associated with fracture. A particular set of normalization is introduced to present the design charts, segregating the roles played by the shape, and the scale, of a bridging law. A single material length, γ 0 E/σ 0 , emerges, where γ 0 is the limiting-separation, σ 0 the bridging-strength, and E the Young's modulus of the solid. It is the huge variation of this length-from a few manometers for atomic bond, to a meter for cross-over fibers - that underlies the richness in material behaviors. Under small-scale bridging conditions, γ 0 E/σ 0 is the only basic length scale in the mechanics problem and represents, with a pre-factor about 0.4, the bridging zone size. A catalog of small-scale bridging solutions is compiled for idealized bridging laws. Large-scale bridging introduces a dimensionless group, a/(γ 0 E/σ 0 ), where a is a length characterizing the component. The group plays a major role in all phenomena associated with bridging, and provides a focus of discussion in this article. For example, it quantifies the bridging scale when a is the unbridged crack length, and notch-sensitivity when a is hole radius. The difference and the connection between Irwin's fracture mechanics and crack bridging concepts are discussed. It is demonstrated that fracture toughness and resistance curve are meaningful only when small-scale bridging conditions prevail, and therefore of limited use in design with composites. Many other mechanical properties of composites, such as strength and notch-sensitivity, can be simulated by invoking large-scale bridging concepts. 37 refs., 21 figs., 3 tabs

49 CFR 236.312 - Movable bridge, interlocking of signal appliances with bridge devices.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Movable bridge, interlocking of signal appliances with bridge devices. 236.312 Section 236.312 Transportation Other Regulations Relating to... SYSTEMS, DEVICES, AND APPLIANCES Interlocking Standards § 236.312 Movable bridge, interlocking of signal...

Cooperativity of complex salt bridges

OpenAIRE

Gvritishvili, Anzor G.; Gribenko, Alexey V.; Makhatadze, George I.

2008-01-01

The energetic contribution of complex salt bridges, in which one charged residue (anchor residue) forms salt bridges with two or more residues simultaneously, has been suggested to have importance for protein stability. Detailed analysis of the net energetics of complex salt bridge formation using double- and triple-mutant cycle analysis revealed conflicting results. In two cases, it was shown that complex salt bridge formation is cooperative, i.e., the net strength of the complex salt bridge...

Comprehensive evaluation of fracture critical bridges.

Science.gov (United States)

2014-02-01

Two-girder steel bridges are classified as fracture critical bridges based on the definition given in the AASHTO LRFD Bridge Design Specifications. In a fracture critical bridge a failure of a tension member leads to collapse of the bridge. However, ...

Experimental elaboration and analysis of dye-sensitized TiO2 solar cells (DSSC) dyed by natural dyes and conductive polymers

Science.gov (United States)

KałuŻyński, P.; Maciak, E.; Herzog, T.; Wójcik, M.

2016-09-01

In this paper we propose low cost and easy in development fully working dye-sensitized solar cell module made with use of a different sensitizing dyes (various anthocyanins and P3HT) for increasing the absorption spectrum, transparent conducting substrates (vaccum spattered chromium and gold), nanometer sized TiO2 film, iodide and methyl viologen dichloride based electrolyte, and a counter electrode (vaccum spattered platinum or carbon). Moreover, some of the different technologies and optimization manufacturing processes were elaborated for energy efficiency increase and were presented in this paper.

Indirect [3H]methyl exchange as a general method for labeling methionine residues: application to calcitonin.

Science.gov (United States)

Barling, P M; Preston, J R; Bibby, N J; Wilson, T

1985-02-01

Native porcine calcitonin from Armour is known to contain two components. It is shown that these can be separated by cation-exchange chromatography in 8 M urea. The technique of [3H]methyl exchange on the methionine residue was used to prepare each of these in a tritiated form. The reduced components formed by demethylation were found to readily reoxidize at neutral pH, to regenerate the disulfide bridge. Evidence is provided to show that the two forms were partially interconverted during these steps. The reoxidized 3H-labeled products were found to be indistinguishable in chemical, immunological, and biological properties from the equivalent components in native porcine calcitonin and had specific activities of approximately 20 Ci/mmol. It is concluded that this labeling method can be conveniently applied to peptides containing one or more disulfide bridges, to give products of high specific activity in acceptable yield, provided appropriate conditions are used to ensure correct reoxidation occurs.

Automated sequence- and stereo-specific assignment of methyl-labeled proteins by paramagnetic relaxation and methyl-methyl nuclear overhauser enhancement spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Venditti, Vincenzo; Fawzi, Nicolas L.; Clore, G. Marius, E-mail: mariusc@mail.nih.gov [National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Laboratory of Chemical Physics (United States)

2011-11-15

Methyl-transverse relaxation optimized spectroscopy is rapidly becoming the preferred NMR technique for probing structure and dynamics of very large proteins up to {approx}1 MDa in molecular size. Data interpretation, however, necessitates assignment of methyl groups which still presents a very challenging and time-consuming process. Here we demonstrate that, in combination with a known 3D structure, paramagnetic relaxation enhancement (PRE), induced by nitroxide spin-labels incorporated at only a few surface-exposed engineered cysteines, provides fast, straightforward and robust access to methyl group resonance assignments, including stereoassignments for the methyl groups of leucine and valine. Neither prior assignments, including backbone assignments, for the protein, nor experiments that transfer magnetization between methyl groups and the protein backbone, are required. PRE-derived assignments are refined by 4D methyl-methyl nuclear Overhauser enhancement data, eliminating ambiguities and errors that may arise due to the high sensitivity of PREs to the potential presence of sparsely-populated transient states.

Timber in Bridge Structures

OpenAIRE

Detkin, Viktoria

2016-01-01

The purpose of this final year project was to study the properties of timber as a structural material and the suitability of wood in load bearing members for bridge structures. For a case study, an existing timber bridge was selected. Due to its condition the bridge should be replaced. The design of a new bridge with steel beams holding a glulam deck was made. During the case study the replacement of steel beams by glulam timber ones was discussed. Some calculations were made in order to ...

Synthesis, structure characterization, and anticancer activity of a novel oxygen-bridged tricyclic Biginelli adduct

Science.gov (United States)

Ibrahim, Mohamed M.; El-Sheshtawy, Hamdy S.; El-Kemary, Maged; Al-Juaid, Salih; Youssef, Mohamed; El-Azab, Islam H.

2017-06-01

Herein, we report the one-pot cyclization of Biginelli Adduct, ethyl 4-(2-hydroxyphenyl)-6-methyl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate (I) to the oxygen-bridged adduct, ethyl 2-methyl-4-thioxo-3,4,5,6-tetrahydro-2H-2,6-methanobenzo[g] [1,3,5]oxadiazocine-11-carboxylate (II) in a high yield and purity under mild reaction condition using zinc(II) perchlorate hexahydrate as a highly efficient catalyst. The cyclic product (II) was characterized both in the solid state and in solution using FT-IR, 1H NMR, and UV-visible spectroscopy. Theoretical calculations using density functional theory with B3LYP/6-311++G(d,p) level were used to further investigate the structure properties. DFT calculations (gas phase) revealed the stability of cyclic compound II (3.45 kcal/mol) than compound I. In addition, the anticancer activity of II was investigated using MCF-7 human breast cell line. The results revealed a moderate activity with 223.55 μg/ml IC50 value.

Field performance of timber bridges. 16, North Siwell Road stress-laminated bridge

Science.gov (United States)

J. A. Kainz

The North Siwell Road bridge was constructed during December 1994 in Hinds County, Mississippi. The bridge is a single-span, stress-laminated T-beam structure that measures 9.1 m (30 ft) long and 8.7 m (28.5 ft) wide. Performance of the bridge was monitored for 24 months, beginning at the time of installation. Monitoring involved gathering and evaluating data relative...

Field performance of timber bridges. 10, Sanborn Brook stress-laminated deck bridge

Science.gov (United States)

P. D. Hilbrich Lee; J. P. Wacker; M. A. Ritter

The Sanborn Brook bridge was constructed in August 1991, 10 miles northeast of Concord, New Hampshire, as part of the demonstration timber bridge program of the USDA Forest Service. The bridge is a simple-span, double-lane, stress-laminated deck superstructure constructed from Southern Pine lumber and is approximately 25 ft long and 28 ft wide with a skew of 14 degrees...

Simulation of multivariate diffusion bridges

DEFF Research Database (Denmark)

Bladt, Mogens; Finch, Samuel; Sørensen, Michael

We propose simple methods for multivariate diffusion bridge simulation, which plays a fundamental role in simulation-based likelihood and Bayesian inference for stochastic differential equations. By a novel application of classical coupling methods, the new approach generalizes a previously...... proposed simulation method for one-dimensional bridges to the mulit-variate setting. First a method of simulating approzimate, but often very accurate, diffusion bridges is proposed. These approximate bridges are used as proposal for easily implementable MCMC algorithms that produce exact diffusion bridges...

Methylation diet and methyl group genetics in risk for adenomatous polyp occurrence

Directory of Open Access Journals (Sweden)

Mark Lucock

2015-06-01

Conclusion: A methylation diet influences methyl group synthesis in the regulation of blood homocysteine level, and is modulated by genetic interactions. Methylation-related nutrients also interact with key genes to modify risk of AP, a precursor of colorectal cancer. Independent of diet, two methylation-related genes (A2756G-MS and A66G-MSR were directly associated with AP occurrence.

Reactions of guanine with methyl chloride and methyl bromide: O6-methylation versus charge transfer complex formation

Science.gov (United States)

Shukla, P. K.; Mishra, P. C.; Suhai, S.

Density functional theory (DFT) at the B3LYP/6-31+G* and B3LYP/AUG-cc-pVDZ levels was employed to study O6-methylation of guanine due to its reactions with methyl chloride and methyl bromide and to obtain explanation as to why the methyl halides cause genotoxicity and possess mutagenic and carcinogenic properties. Geometries of the various isolated species involved in the reactions, reactant complexes (RCs), and product complexes (PCs) were optimized in gas phase. Transition states connecting the reactant complexes with the product complexes were also optimized in gas phase at the same levels of theory. The reactant complexes, product complexes, and transition states were solvated in aqueous media using the polarizable continuum model (PCM) of the self-consistent reaction field theory. Zero-point energy (ZPE) correction to total energy and the corresponding thermal energy correction to enthalpy were made in each case. The reactant complexes of the keto form of guanine with methyl chloride and methyl bromide in water are appreciably more stable than the corresponding complexes involving the enol form of guanine. The nature of binding in the product complexes was found to be of the charge transfer type (O6mG+ · X-, X dbond Cl, Br). Binding of HCl, HBr, and H2O molecules to the PCs obtained with the keto form of guanine did not alter the positions of the halide anions in the PCs, and the charge transfer character of the PCs was also not modified due to this binding. Further, the complexes obtained due to the binding of HCl, HBr, and H2O molecules to the PCs had greater stability than the isolated PCs. The reaction barriers involved in the formation of PCs were found to be quite high (?50 kcal/mol). Mechanisms of genotoxicity, mutagenesis and carcinogenesis caused by the methyl halides appear to involve charge transfer-type complex formation. Thus the mechanisms of these processes involving the methyl halides appear to be quite different from those that involve the

Trans-methylation reactions in plants: focus on the activated methyl cycle.

Science.gov (United States)

Rahikainen, Moona; Alegre, Sara; Trotta, Andrea; Pascual, Jesús; Kangasjärvi, Saijaliisa

2018-02-01

Trans-methylation reactions are vital in basic metabolism, epigenetic regulation, RNA metabolism, and posttranslational control of protein function and therefore fundamental in determining the physiological processes in all living organisms. The plant kingdom is additionally characterized by the production of secondary metabolites that undergo specific hydroxylation, oxidation and methylation reactions to obtain a wide array of different chemical structures. Increasing research efforts have started to reveal the enzymatic pathways underlying the biosynthesis of complex metabolites in plants. Further engineering of these enzymatic machineries offers significant possibilities in the development of bio-based technologies, but necessitates deep understanding of their potential metabolic and regulatory interactions. Trans-methylation reactions are tightly coupled with the so-called activated methyl cycle (AMC), an essential metabolic circuit that maintains the trans-methylation capacity in all living cells. Tight regulation of the AMC is crucial in ensuring accurate trans-methylation reactions in different subcellular compartments, cell types, developmental stages and environmental conditions. This review addresses the organization and posttranslational regulation of the AMC and elaborates its critical role in determining metabolic regulation through modulation of methyl utilization in stress-exposed plants. © 2017 Scandinavian Plant Physiology Society.

Steel-soil composite bridge

DEFF Research Database (Denmark)

Du, Guangli; Pettersson, Lars; Karoumi, Raid

2017-01-01

viability, while their environmental performance is overlooked. Today’s designers are urged to seek new design options to reduce the environmental burdens. Sweden owns more than 24574 bridges and most of them are short spans. Among them, the slab frame bridge (CFB) is a common solution. Soil steel composite...... bridge (SSCB), alternatively, is a functionally equivalent solution to CFB and shows advantages in low cost and easy construction. This paper compares the environmental performance between these two bridge types based on life cycle assessment (LCA). The analysis and result shows that, the SSCB...

Building water bridges in air: Electrohydrodynamics of the floating water bridge

Science.gov (United States)

Marín, Álvaro G.; Lohse, Detlef

2010-12-01

The interaction of electrical fields and liquids can lead to a phenomenon that defies intuition. Some famous examples can be found in electrohydrodynamics as Taylor cones, whipping jets, or noncoalescing drops. A less famous example is the floating water bridge: a slender thread of water held between two glass beakers in which a high voltage difference is applied. Surprisingly, the water bridge defies gravity even when the beakers are separated at distances up to 2 cm. In this paper, experimental measurements and simple models are proposed and discussed for the stability of the bridge and the source of the flow, revealing an important role of polarization forces on the stability of the water bridge. On the other hand, the observed flow can only be explained due to the non-negligible free charge present in the surface. In this sense, the floating water bridge can be considered as an extreme case of a leaky dielectric liquid [J. R. Melcher and G. I. Taylor, Annu. Rev. Fluid Mech. 1, 111 (1969)].

21 CFR 177.2000 - Vinylidene chloride/methyl acrylate/methyl methacrylate polymers.

Science.gov (United States)

2010-04-01

... methacrylate polymers. 177.2000 Section 177.2000 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF...: POLYMERS Substances for Use as Basic Components of Single and Repeated Use Food Contact Surfaces § 177.2000 Vinylidene chloride/methyl acrylate/methyl methacrylate polymers. The vinylidene chloride/methyl acrylate...

Whole-genome methylation caller designed for methyl- DNA ...

African Journals Online (AJOL)

etchie

2013-02-20

Feb 20, 2013 ... Key words: Methyl-DNA immunoprecipitation, next-generation sequencing, Hidden ... its response to environmental cues. .... have a great potential to become the most cost-effective ... hg18 reference genome (set to 0 if not present in retrieved reads). ..... DNA methylation patterns and epigenetic memory.

National Bridge Inventory (NBI) Bridges

Data.gov (United States)

Department of Homeland Security — The NBI is a collection of information (database) describing the more than 600,000 of the Nation's bridges located on public roads, including Interstate Highways,...

Dual chromatin recognition by the histone deacetylase complex HCHC is required for proper DNA methylation in Neurospora crassa

Science.gov (United States)

Honda, Shinji; Bicocca, Vincent T.; Gessaman, Jordan D.; Rountree, Michael R.; Yokoyama, Ayumi; Yu, Eun Y.; Selker, Jeanne M. L.; Selker, Eric U.

2016-01-01

DNA methylation, heterochromatin protein 1 (HP1), histone H3 lysine 9 (H3K9) methylation, histone deacetylation, and highly repeated sequences are prototypical heterochromatic features, but their interrelationships are not fully understood. Prior work showed that H3K9 methylation directs DNA methylation and histone deacetylation via HP1 in Neurospora crassa and that the histone deacetylase complex HCHC is required for proper DNA methylation. The complex consists of the chromodomain proteins HP1 and chromodomain protein 2 (CDP-2), the histone deacetylase HDA-1, and the AT-hook motif protein CDP-2/HDA-1–associated protein (CHAP). We show that the complex is required for proper chromosome segregation, dissect its function, and characterize interactions among its components. Our analyses revealed the existence of an HP1-based DNA methylation pathway independent of its chromodomain. The pathway partially depends on CHAP but not on the CDP-2 chromodomain. CDP-2 serves as a bridge between the recognition of H3K9 trimethylation (H3K9me3) by HP1 and the histone deacetylase activity of HDA-1. CHAP is also critical for HDA-1 localization to heterochromatin. Specifically, the CHAP zinc finger interacts directly with the HDA-1 argonaute-binding protein 2 (Arb2) domain, and the CHAP AT-hook motifs recognize heterochromatic regions by binding to AT-rich DNA. Our data shed light on the interrelationships among the prototypical heterochromatic features and support a model in which dual recognition by the HP1 chromodomain and the CHAP AT-hooks are required for proper heterochromatin formation. PMID:27681634

Wright-Fisher diffusion bridges.

Science.gov (United States)

Griffiths, Robert C; Jenkins, Paul A; Spanò, Dario

2017-10-06

The trajectory of the frequency of an allele which begins at x at time 0 and is known to have frequency z at time T can be modelled by the bridge process of the Wright-Fisher diffusion. Bridges when x=z=0 are particularly interesting because they model the trajectory of the frequency of an allele which appears at a time, then is lost by random drift or mutation after a time T. The coalescent genealogy back in time of a population in a neutral Wright-Fisher diffusion process is well understood. In this paper we obtain a new interpretation of the coalescent genealogy of the population in a bridge from a time t∈(0,T). In a bridge with allele frequencies of 0 at times 0 and T the coalescence structure is that the population coalesces in two directions from t to 0 and t to T such that there is just one lineage of the allele under consideration at times 0 and T. The genealogy in Wright-Fisher diffusion bridges with selection is more complex than in the neutral model, but still with the property of the population branching and coalescing in two directions from time t∈(0,T). The density of the frequency of an allele at time t is expressed in a way that shows coalescence in the two directions. A new algorithm for exact simulation of a neutral Wright-Fisher bridge is derived. This follows from knowing the density of the frequency in a bridge and exact simulation from the Wright-Fisher diffusion. The genealogy of the neutral Wright-Fisher bridge is also modelled by branching Pólya urns, extending a representation in a Wright-Fisher diffusion. This is a new very interesting representation that relates Wright-Fisher bridges to classical urn models in a Bayesian setting. Copyright © 2017 Elsevier Inc. All rights reserved.

DNA Methylation and Methylation Polymorphism in Genetically Stable In vitro Regenerates of Jatropha curcas L. Using Methylation-Sensitive AFLP Markers.

Science.gov (United States)

Rathore, Mangal S; Jha, Bhavanath

2016-03-01

The present investigation aimed to evaluate the degree and pattern of DNA methylation using methylation-sensitive AFLP (MS-AFLP) markers in genetically stable in vitro regenerates of Jatropha curcas L.. The genetically stable in vitro regenerates were raised through direct organogenesis via enhanced axillary shoot bud proliferation (Protocol-1) and in vitro-derived leaf regeneration (Protocol-2). Ten selective combinations of MS-AFLP primers produced 462 and 477 MS-AFLP bands in Protocol-1 (P-1) and Protocol-2 (P-2) regenerates, respectively. In P-1 regenerates, 15.8-31.17 % DNA was found methylated with an average of 25.24 %. In P-2 regenerates, 15.93-32.7 % DNA was found methylated with an average of 24.11 %. Using MS-AFLP in P-1 and P-2 regenerates, 11.52-25.53 % and 13.33-25.47 % polymorphism in methylated DNA was reported, respectively. Compared to the mother plant, P-1 regenerates showed hyper-methylation while P-2 showed hypo-methylation. The results clearly indicated alternation in degree and pattern of DNA methylation; hence, epigenetic instability in the genetically stable in vitro regenerates of J. curcas, developed so far using two different regeneration systems and explants of two different origins. The homologous nucleotide fragments in genomes of P-1 and P-2 regenerates showing methylation re-patterning might be involved in immediate adaptive responses and developmental processes through differential regulation of transcriptome under in vitro conditions.

National Bridge Inventory System (NBI)

Data.gov (United States)

Department of Transportation — The NBI System is the collection of bridge inspection information and costs associated with bridge replacements of structurally deficient bridges on and off the NHS....

Extracorporeal Life Support Bridge to Ventricular Assist Device: The Double Bridge Strategy.

Science.gov (United States)

Marasco, Silvana F; Lo, Casey; Murphy, Deirdre; Summerhayes, Robyn; Quayle, Margaret; Zimmet, Adam; Bailey, Michael

2016-01-01

In patients requiring left ventricular assist device (LVAD) support, it can be difficult to ascertain suitability for long-term mechanical support with LVAD and eventual transplantation. LVAD implantation in a shocked patient is associated with increased morbidity and mortality. Interest is growing in the utilization of extracorporeal life support (ECLS) as a bridge-to-bridge support for these critically unwell patients. Here, we reviewed our experience with ECLS double bridging. We hypothesized that ECLS double bridging would stabilize end-organ dysfunction and reduce ventricular assist device (VAD) implant perioperative mortality. We conducted a retrospective review of prospectively collected data for 58 consecutive patients implanted with a continuous-flow LVAD between January 2010 and December 2013 at The Alfred Hospital, Melbourne, Victoria, Australia. Twenty-three patients required ECLS support pre-LVAD while 35 patients underwent LVAD implantation without an ECLS bridge. Preoperative morbidity in the ECLS bridge group was reflected by increased postoperative intensive care duration, blood loss, blood product use, and postoperative renal failure, but without negative impact upon survival when compared with the no ECLS group. ECLS stabilization improved end-organ function pre-VAD implant with significant improvements in hepatic and renal dysfunction. This series demonstrates that the use of ECLS bridge to VAD stabilizes end-organ dysfunction and reduces VAD implant perioperative mortality from that traditionally reported in these "crash and burn" patients. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Analysis of DNA methylation in Arabidopsis thaliana based on methylation-sensitive AFLP markers.

Science.gov (United States)

Cervera, M T; Ruiz-García, L; Martínez-Zapater, J M

2002-12-01

AFLP analysis using restriction enzyme isoschizomers that differ in their sensitivity to methylation of their recognition sites has been used to analyse the methylation state of anonymous CCGG sequences in Arabidopsis thaliana. The technique was modified to improve the quality of fingerprints and to visualise larger numbers of scorable fragments. Sequencing of amplified fragments indicated that detection was generally associated with non-methylation of the cytosine to which the isoschizomer is sensitive. Comparison of EcoRI/ HpaII and EcoRI/ MspI patterns in different ecotypes revealed that 35-43% of CCGG sites were differentially digested by the isoschizomers. Interestingly, the pattern of digestion among different plants belonging to the same ecotype is highly conserved, with the rate of intra-ecotype methylation-sensitive polymorphisms being less than 1%. However, pairwise comparisons of methylation patterns between samples belonging to different ecotypes revealed differences in up to 34% of the methylation-sensitive polymorphisms. The lack of correlation between inter-ecotype similarity matrices based on methylation-insensitive or methylation-sensitive polymorphisms suggests that whatever the mechanisms regulating methylation may be, they are not related to nucleotide sequence variation.

The global DNA methylation surrogate LINE-1 methylation is correlated with MGMT promoter methylation and is a better prognostic factor for glioma.

Directory of Open Access Journals (Sweden)

Fumiharu Ohka

Full Text Available Gliomas are the most frequently occurring primary brain tumor in the central nervous system of adults. Glioblastoma multiformes (GBMs, WHO grade 4 have a dismal prognosis despite the use of the alkylating agent, temozolomide (TMZ, and even low grade gliomas (LGGs, WHO grade 2 eventually transform to malignant secondary GBMs. Although GBM patients benefit from promoter hypermethylation of the O(6-methylguanine-DNA methyltransferase (MGMT that is the main determinant of resistance to TMZ, recent studies suggested that MGMT promoter methylation is of prognostic as well as predictive significance for the efficacy of TMZ. Glioma-CpG island methylator phenotype (G-CIMP in the global genome was shown to be a significant predictor of improved survival in patients with GBM. Collectively, we hypothesized that MGMT promoter methylation might reflect global DNA methylation. Additionally in LGGs, the significance of MGMT promoter methylation is still undetermined. In the current study, we aimed to determine the correlation between clinical, genetic, and epigenetic profiles including LINE-1 and different cancer-related genes and the clinical outcome in newly diagnosed 57 LGG and 54 GBM patients. Here, we demonstrated that (1 IDH1/2 mutation is closely correlated with MGMT promoter methylation and 1p/19q codeletion in LGGs, (2 LINE-1 methylation levels in primary and secondary GBMs are lower than those in LGGs and normal brain tissues, (3 LINE-1 methylation is proportional to MGMT promoter methylation in gliomas, and (4 higher LINE-1 methylation is a favorable prognostic factor in primary GBMs, even compared to MGMT promoter methylation. As a global DNA methylation marker, LINE-1 may be a promising marker in gliomas.

A study of ion exchange at the poly(butyl viologen)-electrolyte interface by SECM

Energy Technology Data Exchange (ETDEWEB)

Hsu, Chih-Yu.; Vasantha, V.S. [Department of Chemical Engineering, National Taiwan University, Taipei 10617 (China); Ho, Kuo-Chuan [Department of Chemical Engineering, National Taiwan University, Taipei 10617 (China); Institute of Polymer Science and Engineering, National Taiwan University, Taipei 10617 (China)

2008-09-01

In this work, the ion exchange characteristics of poly(butyl viologen) (PBV) thin films on a platinum electrode has been investigated by cyclic voltammetric (CV) scans. Since ferrocyanide anions (Fe(CN){sub 6}{sup 4-}) were added during the polymerization of the PBV thin-film for its stability, Fe(CN){sub 6}{sup 4-} could form charge transfer complex with monomer and co-deposited with polymer. Scanning electrochemical microscopy (SECM) was used to probe the released Fe(CN){sub 6}{sup 4-} ions from PBV film with Os(bpy){sub 3}Cl{sub 2} as a mediator for the approaching process in 0.5 M KCl medium. Mass changes during the redox process of the film were also monitored in-situ by electrochemical quartz crystal microbalance (EQCM). The ion exchange and transport behavior was observed during CV cycling of the film of the SECM and EQCM. The insertion and extraction of anions were found to be potential-dependence. Moreover, the decrease in tip current of released Fe(CN){sub 6}{sup 4-} with increasing cycle number accounted for the ion exchange between Fe(CN){sub 6}{sup 4-} and Cl{sup -} in the KCl electrolyte. However, the Fe(CN){sub 6}{sup 4-}/Fe(CN){sub 6}{sup 3-} redox couple was found to be highly stable between 0.0 and 0.5 V (vs. Ag/AgCl/saturated KCl) in the phosphate buffer solution. Therefore, the electrochemical property of Fe(CN){sub 6}{sup 4-}/Fe(CN){sub 6}{sup 3-} redox couple was studied at different scan rates using CV technique. The peak currents were directly proportional to the scan rate as predicted for a surface confined diffusionless system. The surface coverage ({gamma}) and the concentration of Fe(CN){sub 6}{sup 4-} were determined to be 1.88 x 10{sup -8} mol/cm{sup 2} and 0.641 mol/dm{sup 3}, respectively. By neglecting cations incorporation during redox reaction of the PBV film and also based on the results obtained from energy-dispersive X-ray spectroscopy for the films of as-deposited, reduced and oxidized states, an ion exchange mechanism was

Recognition of methylated DNA through methyl-CpG binding domain proteins

DEFF Research Database (Denmark)

Zou, Xueqing; Ma, Wen; Solov'yov, Ilia

2012-01-01

DNA methylation is a key regulatory control route in epigenetics, involving gene silencing and chromosome inactivation. It has been recognized that methyl-CpG binding domain (MBD) proteins play an important role in interpreting the genetic information encoded by methylated DNA (mDNA). Although...... the function of MBD proteins has attracted considerable attention and is well characterized, the mechanism underlying mDNA recognition by MBD proteins is still poorly understood. In this article, we demonstrate that the methyl-CpG dinucleotides are recognized at the MBD-mDNA interface by two MBD arginines...

Bridge maintenance to enhance corrosion resistance and performance of steel girder bridges

Science.gov (United States)

Moran Yanez, Luis M.

The integrity and efficiency of any national highway system relies on the condition of the various components. Bridges are fundamental elements of a highway system, representing an important investment and a strategic link that facilitates the transport of persons and goods. The cost to rehabilitate or replace a highway bridge represents an important expenditure to the owner, who needs to evaluate the correct time to assume that cost. Among the several factors that affect the condition of steel highway bridges, corrosion is identified as the main problem. In the USA corrosion is the primary cause of structurally deficient steel bridges. The benefit of regular high-pressure superstructure washing and spot painting were evaluated as effective maintenance activities to reduce the corrosion process. The effectiveness of steel girder washing was assessed by developing models of corrosion deterioration of composite steel girders and analyzing steel coupons at the laboratory under atmospheric corrosion for two alternatives: when high-pressure washing was performed and when washing was not considered. The effectiveness of spot painting was assessed by analyzing the corrosion on steel coupons, with small damages, unprotected and protected by spot painting. A parametric analysis of corroded steel girder bridges was considered. The emphasis was focused on the parametric analyses of corroded steel girder bridges under two alternatives: (a) when steel bridge girder washing is performed according to a particular frequency, and (b) when no bridge washing is performed to the girders. The reduction of structural capacity was observed for both alternatives along the structure service life, estimated at 100 years. An economic analysis, using the Life-Cycle Cost Analysis method, demonstrated that it is more cost-effective to perform steel girder washing as a scheduled maintenance activity in contrast to the no washing alternative.

Strength monitoring of bridge constructions and features of its application. Part 2. Continuous monitoring of bridge construction status

Directory of Open Access Journals (Sweden)

Ovchinnikov Igor Georgievich

2014-06-01

Full Text Available The article describes a system of continuous monitoring of bridge constructions — a system of observation over the operating conditions and behavior of the bridge structure, which is aimed at ensuring the preservation of its functional application properties within the specified limits, realized on the continuous, long-term basis with the use of instrumentation and ensures on-line presentation of information on the status of structure. To illustrate, one may consider the existing systems of continuous monitoring for a number of bridge constructions in the United States, Japan, Europe, South Korea, Greece and Russia. The article suggests to examine the systems of continuous monitoring of «Commodore John Barry» truss bridge, «Akashi-Kaikyo» suspension bridge, «Siggenthal» reinforced-concrete arch bridge, «Nimhe» suspension bridge, «Jindo»cable-stayed bridge, «Yandzhon» suspension bridge, «Banghwa» bridge, «Seohae» bridge and «Rio-Antirrio» bridge. In addition one may consider monitoring of the longitudinal launching of the bridge superstructures over the Volga River near the village Pristannoye in Saratov region. Finally, it was drawn the conclusion that monitoring of bridge constructions from the standpoint of their consumers is aimed at solving such important problems as preservation of bridge structures, increase in service life of bridge structures through timely detection of faults and their elimination, as well as preservation of bridge structure carrying capacity by controlling their behavior during the operation and improving the efficiency of expenditure of monetary resources for repair activities by correct determination of time and type of the necessary repair.

Field performance of timber bridges. 15, Pueblo County, Colorado, stress-laminated deck bridge

Science.gov (United States)

L. E. Hislop

The Pueblo County 204B bridge was constructed in March 1990 in Pueblo, Colorado, as a demonstration bridge under the USDA Forest Service Timber Bridge Initiative. The stress-laminated deck superstructure is approximately 10 m long, 9 m wide, and 406 mm deep, with a skew of 10 degrees. Performance monitoring was conducted for 3 years, beginning at...

Principles of Bridge Reliability

DEFF Research Database (Denmark)

Thoft-Christensen, Palle; Nowak, Andrzej S.

The paper gives a brief introduction to the basic principles of structural reliability theory and its application to bridge engineering. Fundamental concepts like failure probability and reliability index are introduced. Ultimate as well as serviceability limit states for bridges are formulated......, and as an example the reliability profile and a sensitivity analyses for a corroded reinforced concrete bridge is shown....

Design and construction of superstructure in prestressed concrete cable-stayed bridge. ; Aomori Bay Bridge. PC shachokyo jobuko no sekkei to seko. ; Aomori Bay Bridge

Energy Technology Data Exchange (ETDEWEB)

Ishibashi, T.; Fujimori, S.; Oba, M.; Tsuyoshi, T. (East Japan Railway Co., Tokyo (Japan))

1991-12-01

Aomori Bay Bridge is a 1,219m long elevated bridge, a part of No.2 Bay Highway of 1,993m in total length crossing over Aomori railway station which was planned in ordecr to integrate the port facilities of Aomori Harbor and expedite cargo traffic smoothly. Of this Bay Bridge, its main bridge portion crossing over Aomori railway station and the sea area was planned as a continuous prestressed concrete cable-stayed bridge of 498m in total length and consisting of three portions including the central portion in which the main span between the central bridge piers was 240m. It is scheduled to open in the summer of 1992. With regard to the design of this bridge, special care for the view of the bridge has been taken covering from the structure style to the accessories. For this bridge, a large scale underground continuous wall solid base with a box-shaped section consisting of 6 chambers was adopted for the base of a main tower. It has the cantilever suspension structure of the wide girder with the inverted Y-shaped pylons. For its stav cable, was adopted a large capacity stay cable with standard tensile strength of 1,942 fabricated on the site and for its covering tube, a FRP tube was adopted. In this article, the construction of the main girder and stay cables, and the construction control during their installation by projection are reported. 7 refs., 14 figs., 9 tabs.

Impact Coefficient Analysis of Long-Span Railway Cable-Stayed Bridge Based on Coupled Vehicle-Bridge Vibration

Directory of Open Access Journals (Sweden)

Yongle Li

2015-01-01

Full Text Available Compared with medium and small span bridges, very limited attention has been paid on the research of the impact coefficient of long-span railway bridges. To estimate the impact effects of long-span railway bridges subjected to moving vehicles, a real long-span railway cable-stayed bridge is regarded as the research object in this study, and a coupled model of vehicle-bridge system is established. The track irregularities are taken as the system excitation and the dynamic responses of the vehicle-bridge system are calculated. The impact effects on main girder, stayed cable, bearings, and bridge tower are discussed at various vehicle speeds. The results show that different components of the long-span railway cable-stayed bridge have different impact coefficients. Even for each part, the impact coefficient is also different at different local positions. It reveals that the impact coefficients in the actual situation may have significant differences with the related code clauses in the present design codes.

A genome-wide methylation study on obesity Differential variability and differential methylation

NARCIS (Netherlands)

Xu, Xiaojing; Su, Shaoyong; Barnes, Vernon A.; De Miguel, Carmen; Pollock, Jennifer; Ownby, Dennis; Shi, Huidong; Zhu, Haidong; Snieder, Harold; Wang, Xiaoling

2013-01-01

Besides differential methylation, DNA methylation variation has recently been proposed and demonstrated to be a potential contributing factor to cancer risk. Here we aim to examine whether differential variability in methylation is also an important feature of obesity, a typical non-malignant common

Maternal intake of methyl-group donors affects DNA methylation of metabolic genes in infants.

Science.gov (United States)

Pauwels, Sara; Ghosh, Manosij; Duca, Radu Corneliu; Bekaert, Bram; Freson, Kathleen; Huybrechts, Inge; Langie, Sabine A S; Koppen, Gudrun; Devlieger, Roland; Godderis, Lode

2017-01-01

Maternal nutrition during pregnancy and infant nutrition in the early postnatal period (lactation) are critically involved in the development and health of the newborn infant. The Maternal Nutrition and Offspring's Epigenome (MANOE) study was set up to assess the effect of maternal methyl-group donor intake (choline, betaine, folate, methionine) on infant DNA methylation. Maternal intake of dietary methyl-group donors was assessed using a food-frequency questionnaire (FFQ). Before and during pregnancy, we evaluated maternal methyl-group donor intake through diet and supplementation (folic acid) in relation to gene-specific ( IGF2 DMR, DNMT1 , LEP , RXRA ) buccal epithelial cell DNA methylation in 6 months old infants ( n  = 114) via pyrosequencing. In the early postnatal period, we determined the effect of maternal choline intake during lactation (in mothers who breast-fed for at least 3 months) on gene-specific buccal DNA methylation ( n  = 65). Maternal dietary and supplemental intake of methyl-group donors (folate, betaine, folic acid), only in the periconception period, was associated with buccal cell DNA methylation in genes related to growth ( IGF2 DMR), metabolism ( RXRA ), and appetite control ( LEP ). A negative association was found between maternal folate and folic acid intake before pregnancy and infant LEP (slope = -1.233, 95% CI -2.342; -0.125, p  = 0.0298) and IGF2 DMR methylation (slope = -0.706, 95% CI -1.242; -0.107, p  = 0.0101), respectively. Positive associations were observed for maternal betaine (slope = 0.875, 95% CI 0.118; 1.633, p  = 0.0241) and folate (slope = 0.685, 95% CI 0.245; 1.125, p  = 0.0027) intake before pregnancy and RXRA methylation. Buccal DNMT1 methylation in the infant was negatively associated with maternal methyl-group donor intake in the first and second trimester of pregnancy and negatively in the third trimester. We found no clear association between maternal choline intake

Field performance of timber bridges. 8, Lynches Woods Park stress-laminated deck bridge

Science.gov (United States)

J. P. Wacker; M. A. Ritter; D. Conger

The Lynches Woods Park bridge was constructed during the summer of 1990 in Newberry, South Carolina. It is a single-span, single-lane, stress-laminated deck superstructure that measures approximately 30 ft long, 16 ft wide, and 14 in. deep. The bridge is unique in that is one of the first known stress-laminated deck bridges to be constructed of Southern Pine lumber...

Salt-bridge energetics in halophilic proteins.

Science.gov (United States)

Nayek, Arnab; Sen Gupta, Parth Sarthi; Banerjee, Shyamashree; Mondal, Buddhadev; Bandyopadhyay, Amal K

2014-01-01

Halophilic proteins have greater abundance of acidic over basic and very low bulky hydrophobic residues. Classical electrostatic stabilization was suggested as the key determinant for halophilic adaptation of protein. However, contribution of specific electrostatic interactions (i.e. salt-bridges) to overall stability of halophilic proteins is yet to be understood. To understand this, we use Adaptive-Poison-Boltzmann-Solver Methods along with our home-built automation to workout net as well as associated component energy terms such as desolvation energy, bridge energy and background energy for 275 salt-bridges from 20 extremely halophilic proteins. We then perform extensive statistical analysis on general and energetic attributes on these salt-bridges. On average, 8 salt-bridges per 150 residues protein were observed which is almost twice than earlier report. Overall contributions of salt-bridges are -3.0 kcal mol-1. Majority (78%) of salt-bridges in our dataset are stable and conserved in nature. Although, average contributions of component energy terms are equal, their individual details vary greatly from one another indicating their sensitivity to local micro-environment. Notably, 35% of salt-bridges in our database are buried and stable. Greater desolvation penalty of these buried salt-bridges are counteracted by stable network salt-bridges apart from favorable equal contributions of bridge and background terms. Recruitment of extensive network salt-bridges (46%) with a net contribution of -5.0 kcal mol-1 per salt-bridge, seems to be a halophilic design wherein favorable average contribution of background term (-10 kcal mol-1) exceeds than that of bridge term (-7 kcal mol-1). Interiors of proteins from halophiles are seen to possess relatively higher abundance of charge and polar side chains than that of mesophiles which seems to be satisfied by cooperative network salt-bridges. Overall, our theoretical analyses provide insight into halophilic signature in its

Bridge the Gap

DEFF Research Database (Denmark)

Marselis, Randi

2017-01-01

This article focuses on photo projects organised for teenage refugees by the Society for Humanistic Photography (Berlin, Germany). These projects, named Bridge the Gap I (2015), and Bridge the Gap II (2016), were carried out in Berlin and brought together teenagers with refugee and German...

Protein methylation in pea chloroplasts

International Nuclear Information System (INIS)

Niemi, K.J.; Adler, J.; Selman, B.R.

1990-01-01

The methylation of chloroplast proteins has been investigated by incubating intact pea (Pisum sativum) chloroplasts with [ 3 H-methyl]-S-adenosylmethionine. Incubation in the light increases the amount of methylation in both the thylakoid and stromal fractions. Numerous thylakoid proteins serve as substrates for the methyltransfer reactions. Three of these thylakoid proteins are methylated to a significantly greater extent in the light than in the dark. The primary stromal polypeptide methylated is the large subunit of ribulose bisphosphate carboxylase/oxygenase. One other stromal polypeptide is also methylated much more in the light than in the dark. Two distinct types of protein methylation occur. One methylinkage is stable to basic conditions whereas a second type is base labile. The base-stable linkage is indicative of N-methylation of amino acid residues while base-lability is suggestive of carboxymethylation of amino acid residues. Labeling in the light increases the percentage of methylation that is base labile in the thylakoid fraction while no difference is observed in the amount of base-labile methylations in light-labeled and dark-labeled stromal proteins. Also suggestive of carboxymethylation is the detection of volatile [ 3 H]methyl radioactivity which increases during the labeling period and is greater in chloroplasts labeled in the light as opposed to being labeled in the dark; this implies in vivo turnover of the [ 3 H]methyl group

Bridge technology report

CERN Document Server

2013-01-01

Please note this is a Short Discount publication. As LANs have proliferated, new technologies and system concepts have come to the fore. One of the key issues is how to interconnect networks. One means of interconnection is to use a 'bridge'. Other competing technologies are repeaters, routers, and gateways. Bridges permit traffic isolation, connect network segments together and operate at the MAC layer. Further, because they operate at the MAC layer, they can handle a variety of protocols such as TCP/IP, SNA, and X.25. This report focuses on the specific technology of bridging two netw

Genome-wide methylation analysis identified sexually dimorphic methylated regions in hybrid tilapia

Science.gov (United States)

Wan, Zi Yi; Xia, Jun Hong; Lin, Grace; Wang, Le; Lin, Valerie C. L.; Yue, Gen Hua

2016-01-01

Sexual dimorphism is an interesting biological phenomenon. Previous studies showed that DNA methylation might play a role in sexual dimorphism. However, the overall picture of the genome-wide methylation landscape in sexually dimorphic species remains unclear. We analyzed the DNA methylation landscape and transcriptome in hybrid tilapia (Oreochromis spp.) using whole genome bisulfite sequencing (WGBS) and RNA-sequencing (RNA-seq). We found 4,757 sexually dimorphic differentially methylated regions (DMRs), with significant clusters of DMRs located on chromosomal regions associated with sex determination. CpG methylation in promoter regions was negatively correlated with the gene expression level. MAPK/ERK pathway was upregulated in male tilapia. We also inferred active cis-regulatory regions (ACRs) in skeletal muscle tissues from WGBS datasets, revealing sexually dimorphic cis-regulatory regions. These results suggest that DNA methylation contribute to sex-specific phenotypes and serve as resources for further investigation to analyze the functions of these regions and their contributions towards sexual dimorphisms. PMID:27782217

DNA sequence explains seemingly disordered methylation levels in partially methylated domains of Mammalian genomes.

Directory of Open Access Journals (Sweden)

Dimos Gaidatzis

2014-02-01

Full Text Available For the most part metazoan genomes are highly methylated and harbor only small regions with low or absent methylation. In contrast, partially methylated domains (PMDs, recently discovered in a variety of cell lines and tissues, do not fit this paradigm as they show partial methylation for large portions (20%-40% of the genome. While in PMDs methylation levels are reduced on average, we found that at single CpG resolution, they show extensive variability along the genome outside of CpG islands and DNase I hypersensitive sites (DHS. Methylation levels range from 0% to 100% in a roughly uniform fashion with only little similarity between neighboring CpGs. A comparison of various PMD-containing methylomes showed that these seemingly disordered states of methylation are strongly conserved across cell types for virtually every PMD. Comparative sequence analysis suggests that DNA sequence is a major determinant of these methylation states. This is further substantiated by a purely sequence based model which can predict 31% (R(2 of the variation in methylation. The model revealed CpG density as the main driving feature promoting methylation, opposite to what has been shown for CpG islands, followed by various dinucleotides immediately flanking the CpG and a minor contribution from sequence preferences reflecting nucleosome positioning. Taken together we provide a reinterpretation for the nucleotide-specific methylation levels observed in PMDs, demonstrate their conservation across tissues and suggest that they are mainly determined by specific DNA sequence features.

Aberrant TET1 Methylation Closely Associated with CpG Island Methylator Phenotype in Colorectal Cancer.

Science.gov (United States)

Ichimura, Norihisa; Shinjo, Keiko; An, Byonggu; Shimizu, Yasuhiro; Yamao, Kenji; Ohka, Fumiharu; Katsushima, Keisuke; Hatanaka, Akira; Tojo, Masayuki; Yamamoto, Eiichiro; Suzuki, Hiromu; Ueda, Minoru; Kondo, Yutaka

2015-08-01

Inactivation of methylcytosine dioxygenase, ten-eleven translocation (TET) is known to be associated with aberrant DNA methylation in cancers. Tumors with a CpG island methylator phenotype (CIMP), a distinct subgroup with extensive DNA methylation, show characteristic features in the case of colorectal cancer. The relationship between TET inactivation and CIMP in colorectal cancers is not well understood. The expression level of TET family genes was compared between CIMP-positive (CIMP-P) and CIMP-negative (CIMP-N) colorectal cancers. Furthermore, DNA methylation profiling, including assessment of the TET1 gene, was assessed in colorectal cancers, as well as colon polyps. The TET1 was silenced by DNA methylation in a subset of colorectal cancers as well as cell lines, expression of which was reactivated by demethylating agent. TET1 methylation was more frequent in CIMP-P (23/55, 42%) than CIMP-N (2/113, 2%, P CIMP-P, 16/40, 40%; CIMP-N, 2/24, 8%; P = 0.002), suggesting that TET1 methylation is an early event in CIMP tumorigenesis. TET1 methylation was significantly associated with BRAF mutation but not with hMLH1 methylation in the CIMP-P colorectal cancers. Colorectal cancers with TET1 methylation have a significantly greater number of DNA methylated genes and less pathological metastasis compared to those without TET1 methylation (P = 0.007 and 0.045, respectively). Our data suggest that TET1 methylation may contribute to the establishment of a unique pathway in respect to CIMP-mediated tumorigenesis, which may be incidental to hMLH1 methylation. In addition, our findings provide evidence that TET1 methylation may be a good biomarker for the prediction of metastasis in colorectal cancer. ©2015 American Association for Cancer Research.

Field performance of timber bridges. 12, Christian Hollow stress-laminated box-beam bridge

Science.gov (United States)

J. P. Wacker; S. C. Catherman; R. G. Winnett

In January 1992, the Christian Hollow bridge was constructed in Steuben County, New York. The bridge is a single-span, stress-laminated box-beam superstructure that is 9.1 m long, 9.8 m wide, and 502 mm deep (30 ft long, 32 ft wide, and 19-3/4 in. deep). The performance of the bridge was continuously monitored for 28 months, beginning shortly after installation....

Evaluating genome-wide DNA methylation changes in mice by Methylation Specific Digital Karyotyping

Directory of Open Access Journals (Sweden)

Maruoka Shuichiro

2008-12-01

Full Text Available Abstract Background The study of genome-wide DNA methylation changes has become more accessible with the development of various array-based technologies though when studying species other than human the choice of applications are limited and not always within reach. In this study, we adapted and tested the applicability of Methylation Specific Digital Karyotyping (MSDK, a non-array based method, for the prospective analysis of epigenetic changes after perinatal nutritional modifications in a mouse model of allergic airway disease. MSDK is a sequenced based method that allows a comprehensive and unbiased methylation profiling. The method generates 21 base pairs long sequence tags derived from specific locations in the genome. The resulting tag frequencies determine in a quantitative manner the methylation level of the corresponding loci. Results Genomic DNA from whole lung was isolated and subjected to MSDK analysis using the methylation-sensitive enzyme Not I as the mapping enzyme and Nla III as the fragmenting enzyme. In a pair wise comparison of the generated mouse MSDK libraries we identified 158 loci that are significantly differentially methylated (P-value = 0.05 after perinatal dietary changes in our mouse model. Quantitative methylation specific PCR and sequence analysis of bisulfate modified genomic DNA confirmed changes in methylation at specific loci. Differences in genomic MSDK tag counts for a selected set of genes, correlated well with changes in transcription levels as measured by real-time PCR. Furthermore serial analysis of gene expression profiling demonstrated a dramatic difference in expressed transcripts in mice exposed to perinatal nutritional changes. Conclusion The genome-wide methylation survey applied in this study allowed for an unbiased methylation profiling revealing subtle changes in DNA methylation in mice maternally exposed to dietary changes in methyl-donor content. The MSDK method is applicable for mouse models

Road Bridges and Culverts, Bridge dataset only includes bridges maintained by Johnson County Public Works in the unincorporated areas, Published in Not Provided, Johnson County Government.

Data.gov (United States)

NSGIC Local Govt | GIS Inventory — Road Bridges and Culverts dataset current as of unknown. Bridge dataset only includes bridges maintained by Johnson County Public Works in the unincorporated areas.

Laboratory Testing of Precast Bridge Beck Panel Transverse Connections for Use in Accelerated Bridge Construction

OpenAIRE

Porter, Scott D.

2009-01-01

Precast concrete bridge deck panels have been used for decades to accelerate bridge construction. Cracking of the transverse connection between panels is a common problem that can damage deck overlays and cause connection leaking leading to corrosion of lower bridge elements. To better understand the behavior of bridge deck transverse female-to-female connections, shear and moment lab testing were performed at Utah State University for the Utah Department of Transportation. Two existing UDOT ...

Human Errors and Bridge Management Systems

DEFF Research Database (Denmark)

Thoft-Christensen, Palle; Nowak, A. S.

on basis of reliability profiles for bridges without human errors are extended to include bridges with human errors. The first rehabilitation distributions for bridges without and with human errors are combined into a joint first rehabilitation distribution. The methodology presented is illustrated...... for reinforced concrete bridges....

A bridge with a view, a view with a bridge : Identifying design considerations for bridges to strengthen regional identity

NARCIS (Netherlands)

Smits, J.E.P.; van der Hoeven, F.D.

2015-01-01

This paper discusses design considerations for creating high quality infrastructural artefacts with an emphasis on bridges. The authors pursue a design study and analysis approach to highlight the specifics of infrastructure design for regional identity, based on their own work on a bridge

Precast concrete elements for accelerated bridge construction : laboratory testing, field testing, evaluation of a precast concrete bridge, Madison County bridge.

Science.gov (United States)

2009-01-01

The importance of rapid construction technologies has been recognized by the Federal Highway Administration (FHWA) and the Iowa : DOT Office of Bridges and Structures. Recognizing this a two-lane single-span precast box girder bridge was constructed ...

Complexation between Methyl Viologen (Paraquat) Bis(Hexafluorophosphate) and Dibenzo[24]Crown-8 Revisited

DEFF Research Database (Denmark)

Gasa, Travis B.; Spruell, Jason M.; Dichtel, William R.

2009-01-01

Paraquat bis(hexafluorophosphate) undergoes stepwise dissociation in acetone. All three species - the neutral molecule, and the mono- and dications - are represented significantly under the experimental conditions typically used in host-guest binding studies. Paraquat forms at least four host...... toward dibenzo[24]crown-8. Thus, the relative abundance of neutral, singly, and doubly charged pseudorotaxanes is identical to the relative abundance of neutral, singly, and doubly charged paraquat unbound with respect to the crown ether in acetone. In the specific case of paraquat/dibenzo[24]crown-8...

Reactivity of OH and O– with aqueous methyl viologen studied by pulse radiolysis

DEFF Research Database (Denmark)

Solar, Sonja; Solar, Wolfgang; Getoff, Nikola

1985-01-01

The behaviour of aqueous MV2+ towards oxidizing radicals (OH and O–) has been investigated in the pH range from 6 to 14 by means of pulse radiolysis. A semi-linear optimization method was applied for resolving the complex reaction mechanism. In the pH range from 6 to 8 the rate constant for attac...

BUILDING A BETTER GLUTEAL BRIDGE: ELECTROMYOGRAPHIC ANALYSIS OF HIP MUSCLE ACTIVITY DURING MODIFIED SINGLE-LEG BRIDGES.

Science.gov (United States)

Lehecka, B J; Edwards, Michael; Haverkamp, Ryan; Martin, Lani; Porter, Kambry; Thach, Kailey; Sack, Richard J; Hakansson, Nils A

2017-08-01

Gluteal strength plays a role in injury prevention, normal gait patterns, eliminating pain, and enhancing athletic performance. Research shows high gluteal muscle activity during a single-leg bridge compared to other gluteal strengthening exercises; however, prior studies have primarily measured muscle activity with the active lower extremity starting in 90 ° of knee flexion with an extended contralateral knee. This standard position has caused reports of hamstring cramping, which may impede optimal gluteal strengthening. The purpose of this study was to determine which modified position for the single-leg bridge is best for preferentially activating the gluteus maximus and medius. Cross-Sectional. Twenty-eight healthy males and females aged 18-30 years were tested in five different, randomized single-leg bridge positions. Electromyography (EMG) electrodes were placed on subjects' gluteus maximus, gluteus medius, rectus femoris, and biceps femoris of their bridge leg (i.e., dominant or kicking leg), as well as the rectus femoris of their contralateral leg. Subjects performed a maximal voluntary isometric contraction (MVIC) for each tested muscle prior to performing five different bridge positions in randomized order. All bridge EMG data were normalized to the corresponding muscle MVIC data. A modified bridge position with the knee of the bridge leg flexed to 135 ° versus the traditional 90 ° of knee flexion demonstrated preferential activation of the gluteus maximus and gluteus medius compared to the traditional single-leg bridge. Hamstring activation significantly decreased (p bridge by flexing the active knee to 135 ° instead of 90 ° minimizes hamstring activity while maintaining high levels of gluteal activation, effectively building a bridge better suited for preferential gluteal activation. 3.

The violin bridge as filter.

Science.gov (United States)

Bissinger, George

2006-07-01

The violin bridge filter role was investigated using modal and acoustic measurements on 12 quality-rated violins combined with systematic bridge rocking frequency f(rock) and wing mass decrements deltam on four bridges for two other violins. No isolated bridge resonances were observed; bridge motions were complex (including a "squat" mode near 0.8 kHz) except for low frequency rigid body pivot motions, all more or less resembling rocking motion at higher frequencies. A conspicuous broad peak near 2.3 kHz in bridge driving point mobility (labeled BH) was seen for good and bad violins. Similar structure was seen in averaged bridge, bridge feet, corpus mobilities and averaged radiativity. No correlation between violin quality and BH driving point, averaged corpus mobility magnitude, or radiativity was found. Increasing averaged-over-f(rock) deltam(g) from 0 to 0.12 generally increased radiativity across the spectrum. Decreasing averaged-over-deltam f(rock) from 3.6 to 2.6 kHz produced consistent decreases in radiativity between 3 and 4.2 kHz, but only few-percent decreases in BH frequency. The lowest f(rock) values were accompanied by significantly reduced radiation from the Helmholtz A0 mode near 280 Hz; this, combined with reduced high frequency output, created overall radiativity profiles quite similar to "bad" violins among the quality-rated violins.

Role of multiprotein bridging factor 1 in archaea: bridging the domains?

NARCIS (Netherlands)

Koning, de B.; Blombach, F.; Wu Hao,; Brouns, S.J.J.; Oost, van der J.

2009-01-01

MBF1 (multiprotein bridging factor 1) is a highly conserved protein in archaea and eukaryotes. It was originally identified as a mediator of the eukaryotic transcription regulator BmFTZ-F1 (Bombyx mori regulator of fushi tarazu). MBF1 was demonstrated to enhance transcription by forming a bridge

MethylMeter(®): bisulfite-free quantitative and sensitive DNA methylation profiling and mutation detection in FFPE samples.

Science.gov (United States)

McCarthy, David; Pulverer, Walter; Weinhaeusel, Andreas; Diago, Oscar R; Hogan, Daniel J; Ostertag, Derek; Hanna, Michelle M

2016-06-01

Development of a sensitive method for DNA methylation profiling and associated mutation detection in clinical samples. Formalin-fixed and paraffin-embedded tumors received by clinical laboratories often contain insufficient DNA for analysis with bisulfite or methylation sensitive restriction enzymes-based methods. To increase sensitivity, methyl-CpG DNA capture and Coupled Abscription PCR Signaling detection were combined in a new assay, MethylMeter(®). Gliomas were analyzed for MGMT methylation, glioma CpG island methylator phenotype and IDH1 R132H. MethylMeter had 100% assay success rate measuring all five biomarkers in formalin-fixed and paraffin-embedded tissue. MGMT methylation results were supported by survival and mRNA expression data. MethylMeter is a sensitive and quantitative method for multitarget DNA methylation profiling and associated mutation detection. The MethylMeter-based GliomaSTRAT assay measures methylation of four targets and one mutation to simultaneously grade gliomas and predict their response to temozolomide. This information is clinically valuable in management of gliomas.

23 CFR 650.809 - Movable span bridges.

Science.gov (United States)

2010-04-01

... 23 Highways 1 2010-04-01 2010-04-01 false Movable span bridges. 650.809 Section 650.809 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.809 Movable span bridges. A fixed bridge...

Sustainable Bridge Infrastructure Procurement

DEFF Research Database (Denmark)

Safi, Mohammed; Du, Guangli; Simonsson, Peter

2016-01-01

The lack of a flexible but systematic approach for integrating lifecycle aspects into bridge investment decisions is a major obstacle hindering the procurement of sustainable bridge infrastructures. This paper addresses this obstacle by introducing a holistic approach that agencies could use...... to procure the most “sustainable” (lifecycle-efficient) bridge through a fair design-build (D-B) tendering process, considering all the main aspects: life-cycle cost (LCC), service life-span, aesthetic demands and environmental impacts (LCA)....

Nonlinearity in oscillating bridges

Directory of Open Access Journals (Sweden)

Filippo Gazzola

2013-09-01

Full Text Available We first recall several historical oscillating bridges that, in some cases, led to collapses. Some of them are quite recent and show that, nowadays, oscillations in suspension bridges are not yet well understood. Next, we survey some attempts to model bridges with differential equations. Although these equations arise from quite different scientific communities, they display some common features. One of them, which we believe to be incorrect, is the acceptance of the linear Hooke law in elasticity. This law should be used only in presence of small deviations from equilibrium, a situation which does not occur in widely oscillating bridges. Then we discuss a couple of recent models whose solutions exhibit self-excited oscillations, the phenomenon visible in real bridges. This suggests a different point of view in modeling equations and gives a strong hint how to modify the existing models in order to obtain a reliable theory. The purpose of this paper is precisely to highlight the necessity of revisiting the classical models, to introduce reliable models, and to indicate the steps we believe necessary to reach this target.

Coupling vibration research on Vehicle-bridge system

Science.gov (United States)

Zhou, Jiguo; Wang, Guihua

2018-01-01

The vehicle-bridge coupling system forms when vehicle running on a bridge. It will generate a relatively large influence on the driving comfort and driving safe when the vibration of the vehicle is bigger. A three-dimensional vehicle-bridge system with biaxial seven degrees of freedom has been establish in this paper based on finite numerical simulation. Adopting the finite element transient numerical simulation to realize the numerical simulation of vehicle-bridge system coupling vibration. Then, analyze the dynamic response of vehicle and bridge while different numbers of vehicles running on the bridge. Got the variation rule of vertical vibration of car body and bridge, and that of the contact force between the wheel and bridge deck. The research results have a reference value for the analysis about the vehicle running on a large-span cabled bridge.

Bimetallic ruthenium complexes bridged by divinylphenylene bearing oligo(ethylene glycol)methylether: synthesis, (spectro)electrochemistry and the lithium cation effect.

Science.gov (United States)

Tian, Li Yan; Liu, Yuan Mei; Tian, Guang-Xuan; Wu, Xiang Hua; Li, Zhen; Kou, Jun-Feng; Ou, Ya-Ping; Liu, Sheng Hua; Fu, Wen-Fu

2014-03-14

A series of 1,4-disubstituted ruthenium-vinyl complexes, (E,E)-[{(PMe3)3(CO)ClRu}2(μ-HC=CH-Ar-CH=CH)], in which the 1,4-diethenylphenylene bridge bears two oligo(ethylene glycol)methyl ether side chains at different positions (2,5- and 2,3-positions), were prepared. The respective products were characterized by elemental analyses and NMR spectroscopy. The structures of complexes 1b and 1e were established by X-ray crystallography. The electronic properties of the complexes were investigated by cyclic voltammetry, and IR and UV-vis/NIR spectroscopies. Electrochemical studies showed that the 2,5-substituents better stabilized the mixed-valence states; the electrochemical behavior was greatly affected by lithium cations, especially complex 1g with 2,3-substituents, which was further supported by IR and UV-vis/NIR spectra changes. Spectroelectrochemical studies showed that the redox chemistry was dominated by the non-innocent character of the bridging fragment.

CpG island methylator phenotype-low (CIMP-low) colorectal cancer shows not only few methylated CIMP-high-specific CpG islands, but also low-level methylation at individual loci.

Science.gov (United States)

Kawasaki, Takako; Ohnishi, Mutsuko; Nosho, Katsuhiko; Suemoto, Yuko; Kirkner, Gregory J; Meyerhardt, Jeffrey A; Fuchs, Charles S; Ogino, Shuji

2008-03-01

The CpG island methylator phenotype (CIMP or CIMP-high) with widespread promoter methylation is a distinct phenotype in colorectal cancer. However, the concept of CIMP-low with less extensive CpG island methylation is still evolving. Our aim is to examine whether density of methylation in individual CpG islands was different between CIMP-low and CIMP-high tumors. Utilizing MethyLight technology and 889 population-based colorectal cancers, we quantified DNA methylation (methylation index, percentage of methylated reference) at 14 CpG islands, including 8 CIMP-high-specific loci (CACNA1G, CDKN2A (p16), CRABP1, IGF2, MLH1, NEUROG1, RUNX3 and SOCS1). Methylation positivity in each locus was defined as methylation index>4. Low-level methylation (methylation index>0, CIMP-high-specific locus was significantly more common in 340 CIMP-low tumors (1/8-5/8 methylation-positive loci) than 133 CIMP-high tumors (> or =6/8 methylation-positive loci) and 416 CIMP-0 tumors (0/8 methylation-positive loci) (PCIMP-high, low-level methylation, was not persistently more prevalent in CIMP-low tumors. In conclusion, compared to CIMP-high and CIMP-0 tumors, CIMP-low colorectal cancers show not only few methylated CIMP-high-specific CpG islands, but also more frequent low-level methylation at individual loci. Our data may provide supporting evidence for a difference in pathogenesis of DNA methylation between CIMP-low and CIMP-high tumors.

Nondestructive testing for bridge diagnosis

International Nuclear Information System (INIS)

Oshima, Toshiyuki; Mikami, Shuichi; Yamazaki, Tomoyuki

1997-01-01

There are many motivations for bridge diagnosis using Nondestructive testing (NDT) to monitor its integrity. The measured frequency and damping on real bridge are compared in one figure as a function of span length and general aspects are explained. These date were measured in every construction of bridges and applied to design new bridges. Ultrasonic testing is also well used for concrete and steel members mainly to detect internal damages or delaminations. Detail analysis on reflected waves gives us more accurate information about the defect. Experimental results are shown as examples in this paper.

Origin and fate of 4-methyl steroid hydrocarbons. I. Diagenesis of 4-methyl sterenes

Energy Technology Data Exchange (ETDEWEB)

Wolff, G.A.; Lamb, N.A.; Maxwell, J.R.

1986-03-01

Treatment of 4-methylcholest-4-ene under mild acid conditions at low temperatures gives chemical evidence for certain features seen in the distributions of sedimentary 4-methyl steroid hydrocarbons, and further indicates that many low temperature diagenetic reactions of steroids are explicable in terms of acid catalyzed rearrangements. Specifically, the results provide: (i) Indirect evidence that the 4-ene skeleton is a key intermediate in the dehydration of 4-methyl stanols in sediments. (ii) An explanation for the distribution of 4-methyl sterenes and A-nor sterenes in the lacustrine Messel shale (Eocene). (iii) An explanation for the presence of 4..beta..-methyl steranes in relatively immature sedimentary rocks, despite the precursor stanols having the 4..cap alpha..-methyl configuration. With increasing maturity in the Paris Basin shales (Lower Toarcian), the less stable 4..beta..-methyl steranes decrease gradually in abundance relative to their 4..cap alpha..-methyl counterparts, at a rate fairly similar to the change in pristane stereochemistry.

Salt bridges: geometrically specific, designable interactions.

Science.gov (United States)

Donald, Jason E; Kulp, Daniel W; DeGrado, William F

2011-03-01

Salt bridges occur frequently in proteins, providing conformational specificity and contributing to molecular recognition and catalysis. We present a comprehensive analysis of these interactions in protein structures by surveying a large database of protein structures. Salt bridges between Asp or Glu and His, Arg, or Lys display extremely well-defined geometric preferences. Several previously observed preferences are confirmed, and others that were previously unrecognized are discovered. Salt bridges are explored for their preferences for different separations in sequence and in space, geometric preferences within proteins and at protein-protein interfaces, co-operativity in networked salt bridges, inclusion within metal-binding sites, preference for acidic electrons, apparent conformational side chain entropy reduction on formation, and degree of burial. Salt bridges occur far more frequently between residues at close than distant sequence separations, but, at close distances, there remain strong preferences for salt bridges at specific separations. Specific types of complex salt bridges, involving three or more members, are also discovered. As we observe a strong relationship between the propensity to form a salt bridge and the placement of salt-bridging residues in protein sequences, we discuss the role that salt bridges might play in kinetically influencing protein folding and thermodynamically stabilizing the native conformation. We also develop a quantitative method to select appropriate crystal structure resolution and B-factor cutoffs. Detailed knowledge of these geometric and sequence dependences should aid de novo design and prediction algorithms. Copyright © 2010 Wiley-Liss, Inc.

Analysis of DNA Cytosine Methylation Patterns Using Methylation-Sensitive Amplification Polymorphism (MSAP).

Science.gov (United States)

Guevara, María Ángeles; de María, Nuria; Sáez-Laguna, Enrique; Vélez, María Dolores; Cervera, María Teresa; Cabezas, José Antonio

2017-01-01

Different molecular techniques have been developed to study either the global level of methylated cytosines or methylation at specific gene sequences. One of them is the methylation-sensitive amplified polymorphism technique (MSAP) which is a modification of amplified fragment length polymorphism (AFLP). It has been used to study methylation of anonymous CCGG sequences in different fungi, plants, and animal species. The main variation of this technique resides on the use of isoschizomers with different methylation sensitivity (such as HpaII and MspI) as a frequent-cutter restriction enzyme. For each sample, MSAP analysis is performed using both EcoRI/HpaII- and EcoRI/MspI-digested samples. A comparative analysis between EcoRI/HpaII and EcoRI/MspI fragment patterns allows the identification of two types of polymorphisms: (1) methylation-insensitive polymorphisms that show common EcoRI/HpaII and EcoRI/MspI patterns but are detected as polymorphic amplified fragments among samples and (2) methylation-sensitive polymorphisms which are associated with the amplified fragments that differ in their presence or absence or in their intensity between EcoRI/HpaII and EcoRI/MspI patterns. This chapter describes a detailed protocol of this technique and discusses the modifications that can be applied to adjust the technology to different species of interest.

An Expert System for Concrete Bridge Management

DEFF Research Database (Denmark)

Brito, J. de; Branco, F. A.; Thoft-Christensen, Palle

1997-01-01

The importance of bridge repair versus new bridge construction has risen in recent decades due to high deterioration rates that have been observed in these structures. Budgets both for building new bridges and keeping the existing ones are always limited. To help rational decision-making, bridge...... management systems are presently being implemented by bridge authorities in several countries. The prototype of an expert system for concrete bridge management is presented in this paper, with its functionality relying on two modules. The inspection module relies on a periodic acquisition of field...... information complemented by a knowledge-based interactive system, BRIDGE-1. To optimize management strategies at the headquarters, the BRIDGE-2 module was implemented, including three submodules: inspection strategy, maintenance and repair....

Model predictive control for a dual active bridge inverter with a floating bridge

OpenAIRE

Chowdhury, Shajjad; Wheeler, Patrick W.; Gerada, C.; Patel, Chintan

2016-01-01

This paper presents a Model Predictive Control technique applied to a dual active bridge inverter where one of the bridges is floating. The proposed floating bridge topology eliminates the need for isolation transformer in a dual inverter system and therefore reduces the size, weight and losses in the system. To achieve multilevel output voltage waveforms the floating inverter DC link capacitor is charged to the half of the main DC link voltage. A finite-set Model Predictive Control technique...

Purification and characterization of the 3-chloro-4-hydroxy-phenylacetate reductive dehalogenase of Desulfitobacterium hafniense

DEFF Research Database (Denmark)

Christensen, Nina; Ahring, Birgitte Kiær; Wohlfarth, Gert

1998-01-01

The membrane-bound 3-chloro-4-hydroxyphenylacetate (Cl-OHPA) reductive dehalogenase from the chlorophenol- educing anaerobe Desulfitobacterium hafniense was purified 11.3-fold to apparent homogeneity in the presence of the detergent CHAPS. The purified dehalogenase catalyzed the reductive...... dechlorination of Cl-OHPA to 4-hydroxyphenylacetate with reduced methyl viologen as the electron donor at a specific activity of 103.2 nkat/mg protein. SDS-PAGErevealed a single protein band with an apparent molecular mass of 46.5 kDa. The enzyme contained 0.68±0.2 mol corrinoid, 12.0±0.7 mol iron, and 13...

Bridge over troubled water?

DEFF Research Database (Denmark)

Svendsen, Gunnar Lind Haase; Nannestad, Peter; Svendsen, Gert Tinggaard

2008-01-01

The problem of integrating non-Western immigrants into Western welfare states is the focus of this paper. To address this issue, we suggest a social capital approach in which we apply the conceptual pair of bridging social capital (BR), which connects an individual to the broader social structure...... relationship between the levels of bridging and bonding capital, suggesting that bonding social capital in the immigrant group does not seem to impede the establishment of the bridging social capital needed for integration....

Evidence for methyl group transfer between the methyl-accepting chemotaxis proteins in Bacillus subtilis

International Nuclear Information System (INIS)

Bedale, W.A.; Nettleton, D.O.; Sopata, C.S.; Thoelke, M.S.; Ordal, G.W.

1988-01-01

The authors present evidence for methyl (as methyl or methoxy) transfer from the methyl-accepting chemotaxis proteins H1 and possibly H3 of Bacillus subtilis to the methyl-accepting chemotaxis protein H2. This methyl transfer, which has been observed in vitro was strongly stimulated by the chemoattractant aspartate and thus may plan an important role in the sensory processing system of this organism. Although radiolabeling of H1 and H3 began at once after the addition of [ 3 H] methionine, radiolabeling of H2 showed a lag. Furthermore, the addition of excess nonradioactive methionine caused immediate exponential delabeling of H1 and H3 while labeling of H2 continued to increase. Methylation of H2 required the chemotactic methyltransferase, probably to first methylate H1 and H3. Aspartate caused increased labeling of H2 and strongly decreased labeling of H1 and H3 after the addition of nonradioactive methionine. Without the addition of nonradioactive methionine, aspartate caused demethylation of H1 and to a lesser extent H3, with an approximately equal increase of methylation of H2

[Analysis of genomic DNA methylation level in radish under cadmium stress by methylation-sensitive amplified polymorphism technique].

Science.gov (United States)

Yang, Jin-Lan; Liu, Li-Wang; Gong, Yi-Qin; Huang, Dan-Qiong; Wang, Feng; He, Ling-Li

2007-06-01

The level of cytosine methylation induced by cadmium in radish (Raphanus sativus L.) genome was analysed using the technique of methylation-sensitive amplified polymorphism (MSAP). The MSAP ratios in radish seedling exposed to cadmium chloride at the concentration of 50, 250 and 500 mg/L were 37%, 43% and 51%, respectively, and the control was 34%; the full methylation levels (C(m)CGG in double strands) were at 23%, 25% and 27%, respectively, while the control was 22%. The level of increase in MSAP and full methylation indicated that de novo methylation occurred in some 5'-CCGG sites under Cd stress. There was significant positive correlation between increase of total DNA methylation level and CdCl(2) concentration. Four types of MSAP patterns: de novo methylation, de-methylation, atypical pattern and no changes of methylation pattern were identified among CdCl(2) treatments and the control. DNA methylation alteration in plants treated with CdCl(2) was mainly through de novo methylation.

Bridge and steel structures. History and vision on bridge erection; Kyoryo kokozobutsu. Kasetsu gijutsu no shorai

Energy Technology Data Exchange (ETDEWEB)

Mukai, S.; Hayashi, T. [Sumitomo Heavy Industries, Ltd., Tokyo (Japan)

1998-08-20

This paper describes the progress of bridge erection technology. It introduces the results of cable erection, rotated/extruded erection, and cantilever erection. The cable erection is a multi point suspension erection using cables. For the rotated/extruded erection, the monolithic construction is conducted on a working yard set in a right angle to the construction position, and the horizontal beams of the bridge piers (corbel girders) are constructed by the rotated method using a slewing base incorporated around the bridge piers at one side. For the construction of stiffening girders of Innoshima-ohashi Bridge of Honshu-Shikoku Joint Bridge in 1978, trussed face bar blocks were extruded from the main tower in order using a travel crane. For the suspension bridges and cable stayed bridges, main towers were erected using various types of cranes. The erection of Tamashima-ohashi Bridge with a weight of 500 ton using an offshore floating crane is introduced as a large block method. Analysis methods and measurement techniques at the site are used in order to analyze the shape in each step under the erection and to ensure the accurate final complete shape. Reduction of the construction cost, improvement of erection technology, and technology development for large-scale projects are subjects in the future. 22 refs., 8 figs., 1 tab.

Reaction products from N-methyl-N-nitrosourea and deoxyribonucleic acid containing thymidine residues. Synthesis and identification of a new methylation product, O4-methyl-thymidine

Science.gov (United States)

Lawley, P. D.; Orr, D. J.; Shah, S. A.; Farmer, P. B.; Jarman, M.

1973-01-01

1. DNA was treated with N-methyl-N-nitrosourea at pH7–8, 37°C, degraded to yield 3- and 7-methylpurines and deoxyribonucleosides and the reaction products were separated by chromatography on ion-exchange resins. The following methods for identification and determination of products were used: with unlabelled N-methyl-N-nitrosourea, u.v. absorption; use of methyl-14C-labelled N-methyl-N-nitrosourea and use of [14C]thymine-labelled DNA. 2. The synthesis of O4-methylthymidine and its identification by u.v. and mass spectroscopy are reported. 3. 3-Methylthymidine and O4-methylthymidine were found as methylation products from N-methyl-N-nitrosourea with thymidine and with DNA, in relatively small yields. Unidentified products containing thymine were found in enzymic digests of N-methyl-N-nitrosourea-treated DNA, which may be phosphotriesters. 4. The possible role of formation of methylthymines in mutagenesis by N-methyl-N-nitrosourea is discussed. PMID:4798180

Dragon bridge - the world largest dragon-shaped (ARCH steel bridge as element of smart city

Directory of Open Access Journals (Sweden)

Chinh Luong Minh

2016-01-01

Full Text Available Dragon Bridge - The world’s largest dragon-shaped steel bridge, with an installation cost of $85 million USD, features 6 lanes for two separate directions, 666 meters of undulating steel in the shape of a dragon in the Ly Dynasty, the symbol of prosperity in Vietnamese culture. This unique and beautifully lit bridge, which also breathes fire and sprays water. It’s the purposeful integration of the lighting hardware articulates the dragon’s form, and the fire-breathing dragon head. This project transcends the notion of monumental bridge with dynamic colour-changing lighting, creating an iconic sculpture in the skyline that is both reverent and whimsical. The signature feature of the bridge was the massive undulating support structure resembling a dragon flying over the river. The dragon is prominent in Vietnamese culture as a symbol of power and nobility. Dragon Bridge stands out as a model of innovation. It has received worldwide attention in the design community and from the global media for its unique arch support system. Dragon Bridge serves as an example of how aesthetic quality of a design can serve cultural, economic and functional purposes. The article presents design solutions of the object and the evaluation of the technical condition before putting the facility into service.

Synthesis of [methyl-14C]crotonobetaine from DL-[methyl-14C]carnitine

International Nuclear Information System (INIS)

Loester, H.; Seim, H.

1996-01-01

The causes of carnitine deficiency syndromes are not completely understood, but decomposition of L-carnitine in vivo is likely to be involved. Carnitine is metabolized to γ-butyrobetaine, and crotonobetaine is probably an intermediate in this pathway. To validate experimentally the precursor-product relationship between the three physiologically occuring γ-betaines - L-carnitine, crotonobetaine, γ-butyrobetaine - labelling with stable or radioactive isotopes became necessary. Methyl-labelled carnitine isomers (L(-)-, D(+)- or DL-) or γ-butyrobetaine can be easily synthesized by methylation of 4-amino-3-hydroxybutyric acid isomers or 4-aminobutyric acid, respectively. Because of problems with the 4-aminocrotonic acid, we synthesized labelled crotonbetaine from labelled carnitine. Thus, DL-[methyl- 14 C]carnitine was dehydrated by reaction with concentrated sulfuric acid. After removal of the latter the products were separated and purified by ion exchange chromatography on DOWEX 50 WX8 (200 - 400 mesh) and gradient elution with hydrochloric acid. In addition to the labelled main product [methyl- 14 C]crotonobetaine (yield about 50 %), [methyl- 14 C]glycine betaine and [methyl- 14 C]acetonyl-trimethylammonium (ATMA) were formed. The end products were identified by combined thin layer chromatography/autoradiography and quantified by liquid scintillation counting. (Author)

Experimental investigation of different fill materials in arch bridges with particular focus on Pearl-Chain Bridges

DEFF Research Database (Denmark)

Lund, Mia Schou Møller; Hansen, Kurt Kielsgaard; Hertz, Kristian Dahl

2016-01-01

Pearl-Chain Bridge technology is a recently developed prefabricated arch solution for road and railway bridges allowing faster, more environmentally friendly, and cheaper bridge construction. This study compared the strength and durability properties of three different types of fill material...

Bridge element deterioration rates.

Science.gov (United States)

2008-10-01

This report describes the development of bridge element deterioration rates using the NYSDOT : bridge inspection database using Markov chains and Weibull-based approaches. It is observed : that Weibull-based approach is more reliable for developing b...

Bridge-Vehicle Impact Assessment

Science.gov (United States)

2011-08-01

Bridges in New York State have been experiencing close to 200 bridge hits a year. These : accidents are attributed to numerous factors including: improperly stored equipment on trucks; : violation of vehicle posting signs; illegal commercial vehicles...

Bridge vehicle impact assessment.

Science.gov (United States)

2011-12-01

Bridges in New York State have been experiencing close to 200 bridge hits a year. These : accidents are attributed to numerous factors including: improperly stored equipment on trucks; : violation of vehicle posting signs; illegal commercial vehicles...

Cord blood buffy coat DNA methylation is comparable to whole cord blood methylation.

Science.gov (United States)

Dou, John; Schmidt, Rebecca J; Benke, Kelly S; Newschaffer, Craig; Hertz-Picciotto, Irva; Croen, Lisa A; Iosif, Ana-Maria; LaSalle, Janine M; Fallin, M Daniele; Bakulski, Kelly M

2018-01-01

Cord blood DNA methylation is associated with numerous health outcomes and environmental exposures. Whole cord blood DNA reflects all nucleated blood cell types, while centrifuging whole blood separates red blood cells, generating a white blood cell buffy coat. Both sample types are used in DNA methylation studies. Cell types have unique methylation patterns and processing can impact cell distributions, which may influence comparability. We evaluated differences in cell composition and DNA methylation between cord blood buffy coat and whole cord blood samples. Cord blood DNA methylation was measured with the Infinium EPIC BeadChip (Illumina) in eight individuals, each contributing buffy coat and whole blood samples. We analyzed principal components (PC) of methylation, performed hierarchical clustering, and computed correlations of mean-centered methylation between pairs. We conducted moderated t-tests on single sites and estimated cell composition. DNA methylation PCs were associated with individual (P PC1 = 1.4 × 10 -9 ; P PC2 = 2.9 × 10 -5 ; P PC3 = 3.8 × 10 -5 ; P PC4 = 4.2 × 10 -6 ; P PC5 = 9.9 × 10 -13 , P PC6 = 1.3 × 10 -11 ) and not with sample type (P PC1-6 >0.7). Samples hierarchically clustered by individual. Pearson correlations of mean-centered methylation between paired samples ranged from r = 0.66 to r = 0.87. No individual site significantly differed between buffy coat and whole cord blood when adjusting for multiple comparisons (five sites had unadjusted Pcoat and whole cord blood are much lower than inter-individual variation, demonstrating that both sample preparation types can be analytically combined and compared.

Wireless Smart Sensor Network System Using SmartBridge Sensor Nodes for Structural Health Monitoring of Existing Concrete Bridges

Science.gov (United States)

Gaviña, J. R.; Uy, F. A.; Carreon, J. D.

2017-06-01

There are over 8000 bridges in the Philippines today according to the Department of Public Works and Highways (DPWH). Currently, visual inspection is the most common practice in monitoring the structural integrity of bridges. However, visual inspections have proven to be insufficient in determining the actual health or condition of a bridge. Structural Health Monitoring (SHM) aims to give, in real-time, a diagnosis of the actual condition of the bridge. In this study, SmartBridge Sensor Nodes were installed on an existing concrete bridge with American Association of State Highway and Transportation Officials (AASHTO) Type IV Girders to gather vibration of the elements of the bridge. Also, standards on the effective installation of SmartBridge Sensor Nodes, such as location and orientation was determined. Acceleration readings from the sensor were then uploaded to a server, wherein they are monitored against certain thresholds, from which, the health of the bridge will be derived. Final output will be a portal or webpage wherein the information, health, and acceleration readings of the bridge will be available for viewing. With levels of access set for different types of users, the main users will have access to download data and reports. Data transmission and webpage access are available online, making the SHM system wireless.

Methyl methacrylate oligomerically-modified clay and its poly(methyl methacrylate) nanocomposites

International Nuclear Information System (INIS)

Zheng Xiaoxia; Jiang, David D.; Wilkie, Charles A.

2005-01-01

A methyl methacrylate oligomerically-modified clay was used to prepare poly(methyl methacrylate) clay nanocomposites by melt blending and the effect of the clay loading level on the modified clay and corresponding nanocomposite was studied. These nanocomposites were characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis and cone calorimetry. The results show a mixed intercalated/delaminated morphology with good nanodispersion. The compatibility between the methylacrylate-subsituted clay and poly(methyl methacrylate) (PMMA) are greatly improved compared to other oligomerically-modified clays

Usability of human Infinium MethylationEPIC BeadChip for mouse DNA methylation studies.

Science.gov (United States)

Needhamsen, Maria; Ewing, Ewoud; Lund, Harald; Gomez-Cabrero, David; Harris, Robert Adam; Kular, Lara; Jagodic, Maja

2017-11-15

The advent of array-based genome-wide DNA methylation methods has enabled quantitative measurement of single CpG methylation status at relatively low cost and sample input. Whereas the use of Infinium Human Methylation BeadChips has shown great utility in clinical studies, no equivalent tool is available for rodent animal samples. We examined the feasibility of using the new Infinium MethylationEPIC BeadChip for studying DNA methylation in mouse. In silico, we identified 19,420 EPIC probes (referred as mEPIC probes), which align with a unique best alignment score to the bisulfite converted reference mouse genome mm10. Further annotation revealed that 85% of mEPIC probes overlapped with mm10.refSeq genes at different genomic features including promoters (TSS1500 and TSS200), 1st exons, 5'UTRs, 3'UTRs, CpG islands, shores, shelves, open seas and FANTOM5 enhancers. Hybridization of mouse samples to Infinium Human MethylationEPIC BeadChips showed successful measurement of mEPIC probes and reproducibility between inter-array biological replicates. Finally, we demonstrated the utility of mEPIC probes for data exploration such as hierarchical clustering. Given the absence of cost and labor convenient genome-wide technologies in the murine system, our findings show that the Infinium MethylationEPIC BeadChip platform is suitable for investigation of the mouse methylome. Furthermore, we provide the "mEPICmanifest" with genomic features, available to users of Infinium Human MethylationEPIC arrays for mouse samples.

A novel method to quantify local CpG methylation density by regional methylation elongation assay on microarray

Directory of Open Access Journals (Sweden)

Qiao Yingjuan

2008-01-01

Full Text Available Abstract Background DNA methylation based techniques are important tools in both clinical diagnostics and therapeutics. But most of these methods only analyze a few CpG sites in a target region. Indeed, difference of site-specific methylation may also lead to a change of methylation density in many cases, and it has been found that the density of methylation is more important than methylation of single CpG site for gene silencing. Results We have developed a novel approach for quantitative analysis of CpG methylation density on the basis of microarray-based hybridization and incorporation of Cy5-dCTP into the Cy3 labeled target DNA by using Taq DNA Polymerase on microarray. The quantification is achieved by measuring Cy5/Cy3 signal ratio which is proportional to methylation density. This methylation-sensitive technique, termed RMEAM (regional methylation elongation assay on microarray, provides several advantages over existing methods used for methylation analysis. It can determine an exact methylation density of the given region, and has potential of high throughput. We demonstrate a use of this method in determining the methylation density of the promoter region of the tumor-related gene MLH1, TERT and MGMT in colorectal carcinoma patients. Conclusion This technique allows for quantitative analysis of regional methylation density, which is the representative of all allelic methylation patterns in the sample. The results show that this technique has the characteristics of simplicity, rapidness, specificity and high-throughput.

Single Molecule Nanoelectrochemistry in Electrical Junctions.

Science.gov (United States)

Nichols, Richard J; Higgins, Simon J

2016-11-15

It is now possible to reliably measure single molecule conductance in a wide variety of environments including organic liquids, ultrahigh vacuum, water, ionic liquids, and electrolytes. The most commonly used methods deploy scanning probe microscopes, mechanically formed break junctions, or lithographically formed nanogap contacts. Molecules are generally captured between a pair of facing electrodes, and the junction current response is measured as a function of bias voltage. Gating electrodes can also be added so that the electrostatic potential at the molecular bridge can be independently controlled by this third noncontacting electrode. This can also be achieved in an electrolytic environment using a four-electrode bipotentiostatic configuration, which allows independent electrode potential control of the two contacting electrodes. This is commonly realized using an electrochemical STM and enables single molecule electrical characterization as a function of electrode potential and redox state of the molecular bridge. This has emerged as a powerful tool in modern interfacial electrochemistry and nanoelectrochemistry for studying charge transport across single molecules as a function of electrode potential and the electrolytic environments. Such measurements are possible in electrolytes ranging from aqueous buffers to nonaqueous ionic liquids. In this Account, we illustrate a number of examples of single molecule electrical measurements under electrode potential control use a scanning tunneling microscope (STM) and demonstrate how these can help in the understanding of charge transport in single molecule junctions. Examples showing charge transport following phase coherent tunneling to incoherent charge hopping across redox active molecular bridges are shown. In the case of bipyridinium (or viologen) molecular wires, it is shown how electrochemical reduction leads to an increase of the single molecule conductance, which is controlled by the liquid electrochemical

Horizontal bridges in polar dielectric liquids

Science.gov (United States)

Woisetschläger, Jakob; Wexler, Adam D.; Holler, Gert; Eisenhut, Mathias; Gatterer, Karl; Fuchs, Elmar C.

2012-01-01

When a high-voltage direct-current is applied to two beakers filled with polar liquid dielectrica like water or methanol, a horizontal bridge forms between the two beakers. By repeating a version of Pellat's experiment, it is shown that a horizontal bridge is stable by the action of electrohydrodynamic pressure. Thus, the static and dynamic properties of the phenomenon called a `floating water bridge' can be explained by the gradient of Maxwell pressure, replenishing the liquid within the bridge against any drainage mechanism. It is also shown that a number of liquids can form stable and long horizontal bridges. The stability of such a connection, and the asymmetry in mass flow through such bridges caused by the formation of ion clouds in the vicinity of the electrodes, is also discussed by two further experiments.

Maternal Methyl-Group Donor Intake and Global DNA (HydroxyMethylation before and during Pregnancy

Directory of Open Access Journals (Sweden)

Sara Pauwels

2016-08-01

Full Text Available It is still unclear to which extent methyl-group intake during pregnancy can affect maternal global DNA (hydroxylmethylation. Pregnancy methylation profiling and its link with methyl-group intake in a healthy population could enhance our understanding of the development of pregnancy related disorders. One hundred forty-eight women were enrolled in the MANOE (MAternal Nutrition and Offspring’s Epigenome study. Thiry-four women were enrolled before pregnancy and 116 during the first trimester of pregnancy. Global DNA (hydroxymethylation in blood using LC-MS/MS and dietary methyl-group intake (methionine, folate, betaine, and choline using a food-frequency questionnaire were estimated pre-pregnancy, during each trimester, and at delivery. Global DNA (hydroxymethylation levels were highest pre-pregnancy and at weeks 18–22 of pregnancy. We observed a positive relation between folic acid and global DNA methylation (p = 0.04 and hydroxymethylation (p = 0.04. A high intake of methionine pre-pregnancy and in the first trimester showed lower (hydroxymethylation percentage in weeks 11–13 and weeks 18–22, respectively. Choline and betaine intake in the first weeks was negatively associated with hydroxymethylation. Women with a high intake of these three methyl groups in the second and third trimester showed higher hyrdoxymethylation/methylation levels in the third trimester. To conclude, a time trend in DNA (hydroxymethylation was found and women with higher methyl-group intake showed higher methylation in the third trimester, and not in earlier phases of pregnancy.

LTBP bridge performance primer.

Science.gov (United States)

2013-12-01

"The performance of bridges is critical to the overall performance of the highway transportation system in the United States. However, many critical aspects of bridge performance are not well understood. The reasons for this include the extreme diver...

33 CFR 115.70 - Advance approval of bridges.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Advance approval of bridges. 115... BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE PROCEDURES § 115.70 Advance approval of bridges. (a) The General Bridge Act of 1946 requires the approval of the location and plans of bridges prior...

Dietary and supplemental maternal methyl-group donor intake and cord blood DNA methylation.

Science.gov (United States)

Pauwels, Sara; Ghosh, Manosij; Duca, Radu Corneliu; Bekaert, Bram; Freson, Kathleen; Huybrechts, Inge; A S Langie, Sabine; Koppen, Gudrun; Devlieger, Roland; Godderis, Lode

2017-01-02

Maternal nutrition is critically involved in the development and health of the fetus. We evaluated maternal methyl-group donor intake through diet (methionine, betaine, choline, folate) and supplementation (folic acid) before and during pregnancy in relation to global DNA methylation and hydroxymethylation and gene specific (IGF2 DMR, DNMT1, LEP, RXRA) cord blood methylation. A total of 115 mother-infant pairs were enrolled in the MAternal Nutrition and Offspring's Epigenome (MANOE) study. The intake of methyl-group donors was assessed using a food-frequency questionnaire. LC-MS/MS and pyrosequencing were used to measure global and gene specific methylation, respectively. Dietary intake of methyl-groups before and during pregnancy was associated with changes in LEP, DNMT1, and RXRA cord blood methylation. Statistically significant higher cord blood LEP methylation was observed when mothers started folic acid supplementation more than 6 months before conception compared with 3-6 months before conception (34.6 ± 6.3% vs. 30.1 ± 3.6%, P = 0.011, LEP CpG1) or no folic acid used before conception (16.2 ± 4.4% vs. 13.9 ± 3%, P = 0.036 for LEP CpG3 and 24.5 ± 3.5% vs. 22.2 ± 3.5%, P = 0.045 for LEP mean CpG). Taking folic acid supplements during the entire pregnancy resulted in statistically significantly higher cord blood RXRA methylation as compared with stopping supplementation in the second trimester (12.3 ± 1.9% vs. 11.1 ± 2%, P = 0.008 for RXRA mean CpG). To conclude, long-term folic acid use before and during pregnancy was associated with higher LEP and RXRA cord blood methylation, respectively. To date, pregnant women are advised to take a folic acid supplement of 400 µg/day from 4 weeks before until 12 weeks of pregnancy. Our results suggest significant epigenetic modifications when taking a folic acid supplement beyond the current advice.

Numerical analysis of dynamic response of vehicle–bridge coupled system on long-span continuous girder bridge

Directory of Open Access Journals (Sweden)

Lipeng An

2016-07-01

Full Text Available To systematically study the vehicle–bridge coupled dynamic response and its change rule with different parameters, a vehicle model with seven degrees of freedom was built and the total potential energy of vehicle space vibration system was deduced. Considering the stimulation of road roughness, the dynamic response equation of vehicle–bridge coupled system was established in accordance with the elastic system principle of total potential energy with stationary value and the “set-in-right-position” rule. On the basis of the self-compiled Fortran program and bridge engineering, the dynamic response of long-span continuous girder bridge under vehicle load was studied. This study also included the calculation of vehicle impact coefficient, evaluation of vibration comfort, and analysis of dynamic response parameters. Results show the impact coefficient changes with lane number and is larger than the value calculated by the “general code for design of highway bridges and culverts (China”. The Dieckmann index of bridge vibration is also related to lane number, and the vibration comfort evaluation is good in normal conditions. The relevant conclusions from parametric analyses have practical significance to dynamic design and daily operation of long-span continuous girder bridges in expressways. Safety and comfort are expected to improve significantly with further control of the vibration of vehicle–bridge system.

Bridge Scour Technology Transfer

Science.gov (United States)

2018-01-24

Scour and flooding are the leading causes of bridge failures in the United States and therefore should be monitored. New applications of tools and technologies are being developed, tested, and implemented to reduce bridge scour risk. The National Coo...

Revised Rules for Concrete Bridges

DEFF Research Database (Denmark)

Thoft-Christensen, Palle; Jensen, F. M.; Middleton, C.

This paper is based on research performed for the Highway Agency, London, UK under the project DPU/9/44 "Revision of Bridge Assessment Rules Based on Whole Life Performance: Concrete Bridges" It contains details of a methodology which can be used to generate Whole Life (WL) reliability profiles....... These WL reliability profiles may be used to establish revised rules for Concrete Bridges....

The stories of two bridges in Ghana

DEFF Research Database (Denmark)

Andreasen, Jørgen

2004-01-01

Public participation in bridge building was promoted by un habitat in the village of Mankrong. The neighbouring village did not participate in the construction of their bridge. The first flooding washed the second bridge down while the "participative bridge" stood up....

Detection of DNA methylation changes in micropropagated banana plants using methylation-sensitive amplification polymorphism (MSAP).

Science.gov (United States)

Peraza-Echeverria, S; Herrera-Valencia, V A.; Kay, A -J.

2001-07-01

The extent of DNA methylation polymorphisms was evaluated in micropropagated banana (Musa AAA cv. 'Grand Naine') derived from either the vegetative apex of the sucker or the floral apex of the male inflorescence using the methylation-sensitive amplification polymorphism (MSAP) technique. In all, 465 fragments, each representing a recognition site cleaved by either or both of the isoschizomers were amplified using eight combinations of primers. A total of 107 sites (23%) were found to be methylated at cytosine in the genome of micropropagated banana plants. In plants micropropagated from the male inflorescence explant 14 (3%) DNA methylation events were polymorphic, while plants micropropagated from the sucker explant produced 8 (1.7%) polymorphisms. No DNA methylation polymorphisms were detected in conventionally propagated banana plants. These results demonstrated the usefulness of MSAP to detect DNA methylation events in micropropagated banana plants and indicate that DNA methylation polymorphisms are associated with micropropagation.

Bridging the Gap

DEFF Research Database (Denmark)

Dahlberg, Rasmus

2016-01-01

The fixed link between Denmark and Sweden connects two busy cities and a large international airport with many of its travelers and employees. 18,000 vehicles and 160 passenger trains transport each day more than 70,000 people across the combined road and rail Øresund Bridge and through the Øresu...... in its final report to the Danish and Swedish transport authorities while drawing upon experiences from two recent comparable cases of infrastructure disruptions: The Champlain Bridge (2009) and the Forth Road Bridge (2015).......The fixed link between Denmark and Sweden connects two busy cities and a large international airport with many of its travelers and employees. 18,000 vehicles and 160 passenger trains transport each day more than 70,000 people across the combined road and rail Øresund Bridge and through the Øresund...... Tunnel, approximately 25,000 of them critical to the regional work market. Even though the risk analysis states that the likelihood of a long-term closure (100C days) is very low Danish and Swedish transport authorities have demanded that the infrastructure operator conducts a survey of the preparedness...

49 CFR 236.766 - Locking, movable bridge.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Locking, movable bridge. 236.766 Section 236.766... Locking, movable bridge. The rail locks, bridge locks, bolt locks, circuit controllers, and electric locks used in providing interlocking protection at a movable bridge. ...

Dynamic assessment of bridge deck performance considering realistic bridge-traffic interaction : research brief

Science.gov (United States)

2017-09-01

This study is to develop simulation methodology to conduct the dynamic assessment of bridge deck performance subjected to traffic. Concrete bridge decks are exposed to daily traffic loads and may experience some surface cracking caused by excessive s...

Development of a precast bridge deck overhang system for the rock creek bridge.

Science.gov (United States)

2008-12-01

Precast, prestressed panels are commonly used at interior beams for bridges in Texas. The use of these : panels provides ease of construction, sufficient capacity, and good economy for the construction of : bridges in Texas. Current practice for the ...

Field performance of timber bridges. 13, Mohawk Canal stress-laminated bridge

Science.gov (United States)

P. D. Hilbrich Lee; X. Lauderdale

The Mohawk Canal bridge was constructed in August 1994, just outside Roll, Arizona. It is a simple-span, double-lane, stress-laminated deck superstructure, approximately 6.4 m (21 ft) long and 10.4 m (34 ft) wide and constructed with Combination 16F-V3 Douglas Fir glued-laminated timber beam laminations. The performance of the bridge was monitored continuously for 2...

Development of inspection robots for bridge cables.

Science.gov (United States)

Yun, Hae-Bum; Kim, Se-Hoon; Wu, Liuliu; Lee, Jong-Jae

2013-01-01

This paper presents the bridge cable inspection robot developed in Korea. Two types of the cable inspection robots were developed for cable-suspension bridges and cable-stayed bridge. The design of the robot system and performance of the NDT techniques associated with the cable inspection robot are discussed. A review on recent advances in emerging robot-based inspection technologies for bridge cables and current bridge cable inspection methods is also presented.

Horizontal bridges in polar dielectric liquids

Energy Technology Data Exchange (ETDEWEB)

Woisetschlaeger, Jakob [Graz University of Technology, Experimental Turbomachinery Research and Optical Measurement Group, Institute for Thermal Turbomachinery and Machine Dynamics, Graz (Austria); Wexler, Adam D.; Fuchs, Elmar C. [Wetsus, Center of Excellence for Sustainable Water Technology, Leeuwarden (Netherlands); Holler, Gert [Graz University of Technology, Institute of Electrical Measurement and Measurement Signal Processing, Graz (Austria); Eisenhut, Mathias [Graz University of Technology, Institute of Analytical Chemistry and Food Chemistry, Graz (Austria); Gatterer, Karl [Graz University of Technology, Institute of Physical and Theoretical Chemistry, Graz (Austria)

2012-01-15

When a high-voltage direct-current is applied to two beakers filled with polar liquid dielectrica like water or methanol, a horizontal bridge forms between the two beakers. By repeating a version of Pellat's experiment, it is shown that a horizontal bridge is stable by the action of electrohydrodynamic pressure. Thus, the static and dynamic properties of the phenomenon called a 'floating water bridge' can be explained by the gradient of Maxwell pressure, replenishing the liquid within the bridge against any drainage mechanism. It is also shown that a number of liquids can form stable and long horizontal bridges. The stability of such a connection, and the asymmetry in mass flow through such bridges caused by the formation of ion clouds in the vicinity of the electrodes, is also discussed by two further experiments. (orig.)

DNA methylation

DEFF Research Database (Denmark)

Williams, Kristine; Christensen, Jesper; Helin, Kristian

2012-01-01

DNA methylation is involved in key cellular processes, including X-chromosome inactivation, imprinting and transcriptional silencing of specific genes and repetitive elements. DNA methylation patterns are frequently perturbed in human diseases such as imprinting disorders and cancer. The recent...... discovery that the three members of the TET protein family can convert 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC) has provided a potential mechanism leading to DNA demethylation. Moreover, the demonstration that TET2 is frequently mutated in haematopoietic tumours suggests that the TET...... proteins are important regulators of cellular identity. Here, we review the current knowledge regarding the function of the TET proteins, and discuss various mechanisms by which they contribute to transcriptional control. We propose that the TET proteins have an important role in regulating DNA methylation...

Lean Construction Applications for Bridge Inspection

Science.gov (United States)

2017-10-01

Lean philosophy was used to analyze the efficiency of bridge inspection. Emphasis was put on identifying activities that add value to the final output, an owner approved bridge inspection report. 26 bridge inspections were shadowed. Time spent on bri...

Spread prestressed concrete slab beam bridges.

Science.gov (United States)

2015-04-01

TxDOT uses prestressed slab beam bridges for short-span bridges ranging from approximately 3050 ft in : length. These bridges have precast, pretensioned slab beams placed immediately adjacent to one another : with a cast-in-place slab made composi...

Degradation of Triazine-2-(14C Metsulfuron-Methyl in Soil from an Oil Palm Plantation.

Directory of Open Access Journals (Sweden)

B S Ismail

Full Text Available Triazine-2-(14C metsulfuron-methyl is a selective, systemic sulfonylurea herbicide. Degradation studies in soils are essential for the evaluation of the persistence of pesticides and their breakdown products. The purpose of the present study was to investigate the degradation of triazine-2-(14C metsulfuron-methyl in soil under laboratory conditions. A High Performance Liquid Chromatograph (HPLC equipped with an UV detector and an on-line radio-chemical detector, plus a Supelco Discovery column (250 x 4.6 mm, 5 μm, and PRP-1 column (305 x 7.0 mm, 10 μm was used for the HPLC analysis. The radioactivity was determined by a Liquid Scintillation Counter (LSC in scintillation fluid. The soil used was both sterilized and non-sterilized in order to observe the involvement of soil microbes. The estimated DT50 and DT90 values of metsulfuron-methyl in a non-sterile system were observed to be 13 and 44 days, whereas in sterilized soil, the DT50 and DT90 were 31 and 70 days, respectively. The principal degradation product after 60 days was CO2. The higher cumulative amount of (14CO2 in (14C-triazine in the non-sterilized soil compared to that in the sterile system suggests that biological degradation by soil micro-organisms significantly contributes to the dissipation of the compound. The major routes of degradation were O-demethylation, sulfonylurea bridge cleavage and the triazine "ring-opened."

Hydrodynamic forces on inundated bridge decks

Science.gov (United States)

2009-05-01

The hydrodynamic forces experienced by an inundated bridge deck have great importance in the design of bridges. Specifically, the drag force, lift force, and the moment acting on the bridge deck under various levels of inundation and a range of flow ...

The origin and fate of 4-methyl steroid hydrocarbons. I. Diagenesis of 4-methyl sterenes

Science.gov (United States)

Wolff, George A.; Lamb, Neil A.; Maxwell, James R.

1986-03-01

Treatment of 4-methylcholest-4-ene under mild acid conditions at low temperatures gives chemical evidence for certain features seen in the distributions of sedimentary 4-methyl steroid hydrocarbons, and further indicates that many low temperature diagenetic reactions of steroids are explicable in terms of acid catalysed rearrangements. Specifically, the results provide: (i) Indirect evidence that the 4-ene skeleton is a key intermediate in the dehydration of 4-methyl stanols in sediments. (ii) An explanation for the distribution of 4-methyl sterenes and A-nor sterenes in the lacustrine Messel shale (Eocene). (iii) An explanation for the presence of 4β-methyl steranes in relatively immature sedimentary rocks, despite the precursor stanols having the 4α-methyl configuration. With increasing maturity in the Paris Basin shales (Lower Toarcian), the less stable 4β-methyl steranes decrease gradually in abundance relative to their 4α-methyl counterparts, at a rate fairly similar to the change in pristane stereochemistry.

A genome-wide methylation study on obesity: differential variability and differential methylation.

Science.gov (United States)

Xu, Xiaojing; Su, Shaoyong; Barnes, Vernon A; De Miguel, Carmen; Pollock, Jennifer; Ownby, Dennis; Shi, Hidong; Zhu, Haidong; Snieder, Harold; Wang, Xiaoling

2013-05-01

Besides differential methylation, DNA methylation variation has recently been proposed and demonstrated to be a potential contributing factor to cancer risk. Here we aim to examine whether differential variability in methylation is also an important feature of obesity, a typical non-malignant common complex disease. We analyzed genome-wide methylation profiles of over 470,000 CpGs in peripheral blood samples from 48 obese and 48 lean African-American youth aged 14-20 y old. A substantial number of differentially variable CpG sites (DVCs), using statistics based on variances, as well as a substantial number of differentially methylated CpG sites (DMCs), using statistics based on means, were identified. Similar to the findings in cancers, DVCs generally exhibited an outlier structure and were more variable in cases than in controls. By randomly splitting the current sample into a discovery and validation set, we observed that both the DVCs and DMCs identified from the first set could independently predict obesity status in the second set. Furthermore, both the genes harboring DMCs and the genes harboring DVCs showed significant enrichment of genes identified by genome-wide association studies on obesity and related diseases, such as hypertension, dyslipidemia, type 2 diabetes and certain types of cancers, supporting their roles in the etiology and pathogenesis of obesity. We generalized the recent finding on methylation variability in cancer research to obesity and demonstrated that differential variability is also an important feature of obesity-related methylation changes. Future studies on the epigenetics of obesity will benefit from both statistics based on means and statistics based on variances.

Development of Inspection Robots for Bridge Cables

Directory of Open Access Journals (Sweden)

Hae-Bum Yun

2013-01-01

Full Text Available This paper presents the bridge cable inspection robot developed in Korea. Two types of the cable inspection robots were developed for cable-suspension bridges and cable-stayed bridge. The design of the robot system and performance of the NDT techniques associated with the cable inspection robot are discussed. A review on recent advances in emerging robot-based inspection technologies for bridge cables and current bridge cable inspection methods is also presented.

Detection and discrimination of maintenance and de novo CpG methylation events using MethylBreak.

Science.gov (United States)

Hsu, William; Mercado, Augustus T; Hsiao, George; Yeh, Jui-Ming; Chen, Chung-Yung

2017-05-15

Understanding the principles governing the establishment and maintenance activities of DNA methyltransferases (DNMTs) can help in the development of predictive biomarkers associated with genetic disorders and diseases. A detection system was developed that distinguishes and quantifies methylation events using methylation-sensitive endonucleases and molecular beacon technology. MethylBreak (MB) is a 22-mer oligonucleotide with one hemimethylated and two unmethylated CpG sites, which are also recognition sites for Sau96I and SacII, and is attached to a fluorophore and a quencher. Maintenance methylation was quantified by fluorescence emission due to the digestion of SacII when the hemimethylated CpG site is methylated, which inhibits Sau96I cleavage. The signal difference between SacII digestion of both MB substrate and maintenance methylated MB corresponds to de novo methylation event. Our technology successfully discriminated and measured both methylation activities at different concentrations of MB and achieved a high correlation coefficient of R 2 =0.997. Additionally, MB was effectively applied to normal and cancer cell lines and in the analysis of enzymatic kinetics and RNA inhibition of recombinant human DNMT1. Copyright © 2017 Elsevier B.V. All rights reserved.

Design and construction of Chiburiko Bridge (stress ribbon bridge). Chiburiko bashi (tsurishoban kyo) no sekkei to seko

Energy Technology Data Exchange (ETDEWEB)

Kamisakoda, K; Tokuyama, S; Sano, K; Onuma, K [Kashima Corp., Tokyo (Japan)

1992-07-30

Chiburiko Bridge lies across Chiburiko which is a lake for agricultural water, and is used by people, carts and cars for administration. It is a stressed-ribbon bridge with the road surface made with concrete covered bands of cables stretched between abutments, and is the first highway bridge in Japan. A report is made on the plan and construction of the bridge. Integration of the precast slab with the cast-in-place concrete as well as mutual integration of the precast slabs are validated by the use of a reproduced model of a part of the bridge. Floor slabs are suspended by cables, and can be constructed with no form nor support by integrating cast-in-place concrete with the precast slabs on mutually joined precast slabs. It has been said that the stressed-ribbon bridge has a structure suitable for long span bridges because it has a simple structure. Studies, however, seems to be necessary on the impact caused by running of vehicles and on the wind resisting stability. 3 refs., 17 figs., 2 tabs.

The South Carolina bridge-scour envelope curves

Science.gov (United States)

Benedict, Stephen T.; Feaster, Toby D.; Caldwell, Andral W.

2016-09-30

The U.S. Geological Survey, in cooperation with the South Carolina Department of Transportation, conducted a series of three field investigations to evaluate historical, riverine bridge scour in the Piedmont and Coastal Plain regions of South Carolina. These investigations included data collected at 231 riverine bridges, which lead to the development of bridge-scour envelope curves for clear-water and live-bed components of scour. The application and limitations of the South Carolina bridge-scour envelope curves were documented in four reports, each report addressing selected components of bridge scour. The current investigation (2016) synthesizes the findings of these previous reports into a guidance manual providing an integrated procedure for applying the envelope curves. Additionally, the investigation provides limited verification for selected bridge-scour envelope curves by comparing them to field data collected outside of South Carolina from previously published sources. Although the bridge-scour envelope curves have limitations, they are useful supplementary tools for assessing the potential for scour at riverine bridges in South Carolina.

Assessment of structural condition of Libeň Bridge

Directory of Open Access Journals (Sweden)

Kněž Petr

2017-01-01

Full Text Available The paper presents diagnostic and load tests of the Inundation bridge which is part of a group of bridges called The Libeň bridge group in Prague. The Libeň bridge group consists of two arched and several framed bridges spanning the Vltava river. One of the vaulted bridges consists of 5 arches and the other vaulted bridge (called Inundation bridge consists of only one arch. Arched bridges are extraordinary structures with both technical and historical value. Since the inundation bridge has the largest arch of whole group, it was selected for testing purposes. The bridge is assembled with three-hinged arch made of concrete. The hinges are made of reinforced concrete and lead contact slabs. Detailed measurements of geometry and material properties were made on the bridge. Based on these measurements a computer model was created to verify the behavior of the structure. Both static and dynamic calculations were performed. Measurements of dynamic characteristics were made during normal operation and with hydraulic vibration exciter. This article will focus on comparing the results of dynamic calculation of the modeled structure and properties measured on real structure excited by hydraulic vibration exciter.

Students design composite bridges

NARCIS (Netherlands)

Stark, J.W.B.; Galjaard, J.C.; Brekelmans, J.W.P.M.

1999-01-01

The paper gives an overview of recent research on steel-concrete composite bridge design by students of Delft University of Technology doing their master's thesis. Primary objective of this research was to find possibilities for application of steel-concrete composite bridges in the Netherlands,

33 CFR 118.140 - Painting bridge piers.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Painting bridge piers. 118.140 Section 118.140 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.140 Painting bridge piers. The District Commander may require...

Superconductivity in small metal bridges

International Nuclear Information System (INIS)

Hannah, E.C.

1975-01-01

Josephson effects in weaklinks are discussed for low and high frequency regimes using simple perturbation techniques. It is proven that no measurement of the supercurrent dependence upon frequency above the Riedel peak frequency can be made using rf sources whose frequencies are below the Riedel peak. Thus the bulk of work done in the field on the high frequency structure of the Josephson current is shown to be invalid. Metal bridges shorter than a newly defined temperature independent length for superconductors, l/sub PHONON/, are proven to be identical in their Josephson current behavior to tunneling junctions. The BCS gap equation is generalized to include voltage gradient effects on pairs within the bridge. The oscillation frequency for long bridges (l/sub BRIDGE/ greater than l/sub PHONON/) is shown to be limited to less than 10'' Hz. An experimental test of the new voltage dependent gap is made as well as tests of the pair reforming time of bridges

Mobility and molecular ions of dimethyl methyl phosphonate, methyl salicylate and acetone

Science.gov (United States)

Nowak, D. M.

1983-06-01

The mobilities of positive and negative reactant ions are reported for (H2O)nH(+); (H2O)2O2 and (H2O)2CO3(-) ion clusters. The formation of positive DMMP monomer and dimer is reported, and equilbria molecular reactions are reported. Acetone is reported as forming a dimer at 81 ppb with a reduced mobility (K sub o) of 1.82, Methyl salicylate is shown to form a protonated and hydrated positive monomer. Mixtures of DMMP and methyl salicylate with acetone showed a substantial change in DMMP ion clustering and little or no change in the methyl salicylate mobility spectra. Negative ions were not observed for DMMP, methyl salicylate, acetone and the mixtures under the conditions reported.

Bridge scour monitoring technologies : development of evaluation and selection protocols for application on river bridges in Minnesota.

Science.gov (United States)

2010-03-01

Bridge failure or loss of structural integrity can result from scour of riverbed sediment near bridge abutments or : piers during high-flow events in rivers. In the past 20 years, several methods of monitoring bridge scour have been : developed spann...

The roles of anion and solvent transport during the redox switching process at a poly(butyl viologen) film studied by an EQCM

Energy Technology Data Exchange (ETDEWEB)

Hsu, Chih-Yu.; Liao, Chun-Hao [Department of Chemical Engineering, National Taiwan University, Taipei 10617 (China); Ho, Kuo-Chuan [Department of Chemical Engineering, National Taiwan University, Taipei 10617 (China); Institute of Polymer Science and Engineering, National Taiwan University, Taipei 10617 (China)

2008-02-15

In this study, three electrolytes (KCl, LiCl, and KNO{sub 3}, each at 0.5 M in aqueous solution) were chosen to study the ion and solvent effect on the redox performance of poly(butyl viologen) (PBV) thin-films between its di-cation and radical-cation state, which is referred as its first redox couple. Before considering the role of ionic transport on the redox process, the exchange between ferrocyanide and anion should be completed. Since the deposition solution of PBV contains potassium ferrocyanide, the residual ferrocyanides inside the films would be exchanged by smaller anions from the bulk solution during the redox reaction of PBV. From cyclic voltammetry (CV) and electrochemical quartz crystal microbalance (EQCM) results, the exchange was almost complete around 50 cycles when scanning the potential within its first redox range. After completion of the exchange process, the transfer would reach a steady state. At 50 cycles, the EQCM results suggested that the transport involves anions and water only for both being extracted upon reduction and being inserted upon oxidation. Therefore, we could obtain the molar fluxes of Cl{sup -}, NO{sub 3}{sup -}, and water. Besides, the average numbers of accompanying water were calculated to be about 24.8 per Cl{sup -} and 14.2 per NO{sub 3}{sup -} upon redox switching process. The instantaneous water to anion molar ratios at any potential were also obtained for Cl{sup -} and NO{sub 3}{sup -}. (author)

Blood-brain transfer and antinociception of linear and cyclic N-methyl-guanidine and thiourea-enkephalins

DEFF Research Database (Denmark)

Verbeken, Mathieu; Wynendaele, Evelien; Mauchauffee, Elodie

2015-01-01

Enkephalins are active in regulation of nociception in the body and are key in development of new synthetic peptide analogs that target centrally located opioid receptors. In this study, we investigated the in vivo blood–brain barrier (BBB) penetration behavior and antinociceptive activity of two...... cyclic enkephalin analogs with a thiourea (CycS) or a N-methyl-guanidine bridge (CycNMe), and their linear counterparts (LinS and LinNMe) in mice, as well as their in vitro metabolic stability. 125I-LinS had the highest blood–brain clearance (K1 = 3.46 μL/g min), followed by 125I-LinNMe, 125I...

Multiple Bistability in Quinonoid-Bridged Diiron(II) Complexes: Influence of Bridge Symmetry on Bistable Properties.

Science.gov (United States)

van der Meer, Margarethe; Rechkemmer, Yvonne; Breitgoff, Frauke D; Marx, Raphael; Neugebauer, Petr; Frank, Uta; van Slageren, Joris; Sarkar, Biprajit

2016-11-21

Quinonoid bridges are well-suited for generating dinuclear assemblies that might display various bistable properties. In this contribution we present two diiron(II) complexes where the iron(II) centers are either bridged by the doubly deprotonated form of a symmetrically substituted quinonoid bridge, 2,5-bis[4-(isopropyl)anilino]-1,4-benzoquinone (H 2 L2') with a [O,N,O,N] donor set, or with the doubly deprotonated form of an unsymmetrically substituted quinonoid bridge, 2-[4-(isopropyl)anilino]-5-hydroxy-1,4-benzoquinone (H 2 L5') with a [O,O,O,N] donor set. Both complexes display temperature-induced spin crossover (SCO). The nature of the SCO is strongly dependent on the bridging ligand, with only the complex with the [O,O,O,N] donor set displaying a prominent hysteresis loop of about 55 K. Importantly, only the latter complex also shows a pronounced light-induced spin state change. Furthermore, both complexes can be oxidized to the mixed-valent iron(II)-iron(III) form, and the nature of the bridge determines the Robin and Day classification of these forms. Both complexes have been probed by a battery of electrochemical, spectroscopic, and magnetic methods, and this combined approach is used to shed light on the electronic structures of the complexes and on bistability. The results presented here thus show the potential of using the relatively new class of unsymmetrically substituted bridging quinonoid ligands for generating intriguing bistable properties and for performing site-specific magnetic switching.

33 CFR 118.90 - Bridges crossing channel obliquely.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Bridges crossing channel obliquely. 118.90 Section 118.90 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.90 Bridges crossing channel obliquely. Bridges...

Evolution of DNA Methylation across Insects.

Science.gov (United States)

Bewick, Adam J; Vogel, Kevin J; Moore, Allen J; Schmitz, Robert J

2017-03-01

DNA methylation contributes to gene and transcriptional regulation in eukaryotes, and therefore has been hypothesized to facilitate the evolution of plastic traits such as sociality in insects. However, DNA methylation is sparsely studied in insects. Therefore, we documented patterns of DNA methylation across a wide diversity of insects. We predicted that underlying enzymatic machinery is concordant with patterns of DNA methylation. Finally, given the suggestion that DNA methylation facilitated social evolution in Hymenoptera, we tested the hypothesis that the DNA methylation system will be associated with presence/absence of sociality among other insect orders. We found DNA methylation to be widespread, detected in all orders examined except Diptera (flies). Whole genome bisulfite sequencing showed that orders differed in levels of DNA methylation. Hymenopteran (ants, bees, wasps and sawflies) had some of the lowest levels, including several potential losses. Blattodea (cockroaches and termites) show all possible patterns, including a potential loss of DNA methylation in a eusocial species whereas solitary species had the highest levels. Species with DNA methylation do not always possess the typical enzymatic machinery. We identified a gene duplication event in the maintenance DNA methyltransferase 1 (DNMT1) that is shared by some Hymenoptera, and paralogs have experienced divergent, nonneutral evolution. This diversity and nonneutral evolution of underlying machinery suggests alternative DNA methylation pathways may exist. Phylogenetically corrected comparisons revealed no evidence that supports evolutionary association between sociality and DNA methylation. Future functional studies will be required to advance our understanding of DNA methylation in insects. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

33 CFR 118.100 - Retroreflective panels on bridge piers.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Retroreflective panels on bridge... SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.100 Retroreflective panels on bridge piers. The... 12 inches square. (c) To mark bridge piers or channel sides on bridges not required to have bridge...

Concrete-Filled Steel Tube Arch Bridges in China

Directory of Open Access Journals (Sweden)

Jielian Zheng

2018-02-01

Full Text Available In the past 20 years, great progress has been achieved in China in the construction of concrete-filled steel tube (CFST arch bridges and concrete arch bridges with a CFST skeleton. The span of these bridges has been increasing rapidly, which is rare in the history of bridge development. The large-scale construction of expressways and high-speed railways demands the development of long-span arch bridges, and advances in design and construction techniques have made it possible to construct such bridges. In the present study, the current status, development, and major innovative technologies of CFST arch bridges and concrete arch bridges with a CFST skeleton in China are elaborated. This paper covers the key construction technologies of CFST arch bridges, such as the design, manufacture, and installation of steel tube arch trusses, the preparation and pouring of in-tube concrete, and the construction of the world’s longest CFST arch bridge—the First Hejiang Yangtze River Bridge. The main construction technologies of reinforced concrete arch bridges are also presented, which include cable-stayed fastening-hanging cantilever assembly, adjusting the load by means of stay cables, surrounding the concrete for arch rib pouring, and so forth. In addition, the construction of two CFST skeleton concrete arch bridges—the Guangxi Yongning Yong River Bridge and the Yunnan–Guangxi Railway Nanpan River Bridge—is discussed. CFST arch bridges in China have already gained a world-leading position; with the continuous innovation of key technologies, China will become the new leader in promoting the development of arch bridges. Keywords: Concrete-filled steel tube (CFST arch bridge, Steel-reinforced concrete arch bridge, Cable-stayed fastening-hanging cantilever assembly, Vacuum-assisted pouring in-tube concrete, Adjusting load by stay cables

An aqueous all-organic redox-flow battery employing a (2,2,6,6-tetramethylpiperidin-1-yl)oxyl-containing polymer as catholyte and dimethyl viologen dichloride as anolyte

Science.gov (United States)

Hagemann, Tino; Winsberg, Jan; Grube, Mandy; Nischang, Ivo; Janoschka, Tobias; Martin, Norbert; Hager, Martin D.; Schubert, Ulrich S.

2018-02-01

Herein we present a new redox-flow battery (RFB) that employs a (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) containing copolymer (P1) as catholyte and the viologen derivative N,N‧-dimethyl-4,4‧-bipyridinium dichloride (MV) as anolyte in an aqueous sodium chloride solution. This is the first time that a combination of an organic polymer and a low-molar-mass organic redox-active material is presented. The electrochemical behavior of the utilized charge-storage materials were investigated by cyclic voltammetry (CV) and feature reversible redox-reactions at E½ = 0.7 V (TEMPO/TEMPO+) and E½ = -0.6 V vs. AgCl/Ag (MV++/MV+•), which lead to a promising cell voltage of 1.3 V in the subsequent battery application. Studies were performed to determine the most suitable anion-exchange membrane (AEM), the ideal conducting salt concentration and the optimal flow rate. The resulting battery reveals a stable charge/discharge performance over 100 consecutive cycles with coulombic efficiencies of up to 95%, a high energy efficiency of 85% and an overall energy density of the electrolyte system of 3.8 W h L-1.

Reliability Modeling of Double Beam Bridge Crane

Science.gov (United States)

Han, Zhu; Tong, Yifei; Luan, Jiahui; Xiangdong, Li

2018-05-01

This paper briefly described the structure of double beam bridge crane and the basic parameters of double beam bridge crane are defined. According to the structure and system division of double beam bridge crane, the reliability architecture of double beam bridge crane system is proposed, and the reliability mathematical model is constructed.

POLYMERIZATION OF METHYL METHACRYLATE WITH ETHYLENE BRIDGED HETERODINUCLEAR METALLOCENE OF SAMARIUM AND TITANIUM-STUDY ON SYNERGISM AND KINETICS

Institute of Scientific and Technical Information of China (English)

无

2001-01-01

Comparison of MMA polymerization results with samarocene chloride, titanocene chloride and the title heterodinuclear (Sm-Ti) catalyst, respectively, showed synergism in the Sm-Ligand-Ti system, which ob viously influenced the polymerization behaviors, for example, of yielding higher activity and higher molecular weight polymer. Kinetic studies on polymerization of MMA with ethylene bridged samarocene and titanocene chloride/M(i-Bu) 3 showed that the polymerization rate was first-order on the catalyst concentration, and 1.9- order on the monomer. The overall activation energy measured was 52.8 kJ/mol.

LIGHT BRIDGE IN A DEVELOPING ACTIVE REGION. I. OBSERVATION OF LIGHT BRIDGE AND ITS DYNAMIC ACTIVITY PHENOMENA

International Nuclear Information System (INIS)

Toriumi, Shin; Katsukawa, Yukio; Cheung, Mark C. M.

2015-01-01

Light bridges, the bright structures that divide the umbra of sunspots and pores into smaller pieces, are known to produce a wide variety of activity events in solar active regions (ARs). It is also known that the light bridges appear in the assembling process of nascent sunspots. The ultimate goal of this series of papers is to reveal the nature of light bridges in developing ARs and the occurrence of activity events associated with the light bridge structures from both observational and numerical approaches. In this first paper, exploiting the observational data obtained by Hinode, the Interface Region Imaging Spectrograph, and the Solar Dynamics Observatory, we investigate the detailed structure of the light bridge in NOAA AR 11974 and its dynamic activity phenomena. As a result, we find that the light bridge has a weak, horizontal magnetic field, which is transported from the interior by a large-scale convective upflow and is surrounded by strong, vertical fields of adjacent pores. In the chromosphere above the bridge, a transient brightening occurs repeatedly and intermittently, followed by a recurrent dark surge ejection into higher altitudes. Our analysis indicates that the brightening is the plasma heating due to magnetic reconnection at lower altitudes, while the dark surge is the cool, dense plasma ejected from the reconnection region. From the observational results, we conclude that the dynamic activity observed in a light bridge structure such as chromospheric brightenings and dark surge ejections are driven by magnetoconvective evolution within the light bridge and its interaction with the surrounding magnetic fields

LIGHT BRIDGE IN A DEVELOPING ACTIVE REGION. I. OBSERVATION OF LIGHT BRIDGE AND ITS DYNAMIC ACTIVITY PHENOMENA

Energy Technology Data Exchange (ETDEWEB)

Toriumi, Shin; Katsukawa, Yukio [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Cheung, Mark C. M., E-mail: shin.toriumi@nao.ac.jp [Lockheed Martin Solar and Astrophysics Laboratory, 3251 Hanover Street, Building/252, Palo Alto, CA 94304 (United States)

2015-10-01

Light bridges, the bright structures that divide the umbra of sunspots and pores into smaller pieces, are known to produce a wide variety of activity events in solar active regions (ARs). It is also known that the light bridges appear in the assembling process of nascent sunspots. The ultimate goal of this series of papers is to reveal the nature of light bridges in developing ARs and the occurrence of activity events associated with the light bridge structures from both observational and numerical approaches. In this first paper, exploiting the observational data obtained by Hinode, the Interface Region Imaging Spectrograph, and the Solar Dynamics Observatory, we investigate the detailed structure of the light bridge in NOAA AR 11974 and its dynamic activity phenomena. As a result, we find that the light bridge has a weak, horizontal magnetic field, which is transported from the interior by a large-scale convective upflow and is surrounded by strong, vertical fields of adjacent pores. In the chromosphere above the bridge, a transient brightening occurs repeatedly and intermittently, followed by a recurrent dark surge ejection into higher altitudes. Our analysis indicates that the brightening is the plasma heating due to magnetic reconnection at lower altitudes, while the dark surge is the cool, dense plasma ejected from the reconnection region. From the observational results, we conclude that the dynamic activity observed in a light bridge structure such as chromospheric brightenings and dark surge ejections are driven by magnetoconvective evolution within the light bridge and its interaction with the surrounding magnetic fields.

Bridge Aesthetics and Structural Honesty

DEFF Research Database (Denmark)

Gimsing, Niels Jørgen

1999-01-01

In bridges the overall form must be chosen with due respect to the transmission of forces if efficient structures shall be created, The design must therefore be governed by experienced structural engineers - in some cases assisted by aesthetic advisers on specific issues. Some basic requirements...... decisive for choosing the form of trusses, arches and cable-stayed bridges are outlined, and several examples show bridges designed without giving priority to the structural aspects....

Strategies For The Replacement Of Historic Bridge Guardrails

OpenAIRE

Clauss, Adam J.

2014-01-01

Bridges that are designated historic present a special challenge to bridge engineers whenever rehabilitation work or improvements are made to the bridges. Federal and state laws protect historically significant bridges, and railings on these bridges can be subject to protection because of the role they play in aesthetics. Unfortunately, original railings on historic bridges do not typically meet current crash-test requirements and typically do not meet current standards for railing height and...

Relationship between methylation status of vitamin D-related genes, vitamin D levels, and methyl-donor biochemistry

Directory of Open Access Journals (Sweden)

Emma Louise Beckett

2016-12-01

Full Text Available Vitamin D is known for its role in the regulation of gene expression via the vitamin D receptor, a nuclear transcription factor. More recently, a role for vitamin D in regulating DNA methylation has been identified as an additional mechanism of modulation of gene expression. How methylation status influences vitamin D metabolism and response pathways is not yet clear. Therefore, we aimed to assess the relationship between plasma 25-hydroxycholecalciferol (25(OHD and the methylation status of vitamin D metabolism enzyme genes (CYP2R1, CYP27B1 and CYP24A1 and the vitamin D receptor gene (VDR. This analysis was conducted in the context of dietary vitamin D, and background methyl donor related biochemistry, with adjustment for several dietary and lifestyle variables. Percentage methylation at CpG sites was assessed in peripheral blood cells using methylation sensitive and dependent enzymes and qPCR. Standard analytical techniques were used to determine plasma 25(OHD and homocysteine, and serum folate and B12, with the relationship to methylation status assessed using multi-variable regression analysis. CYP2R1 and VDR methylation were found to be independent predictors of plasma 25(OHD, when adjusted for vitamin D intake and other lifestyle variables. CYP24A1 was related to plasma 25(OHD directly, but not in the context of vitamin D intake. Methyl-group donor biochemistry was associated with the methylation status of some genes, but did not alter the relationship between methylation and plasma 25(OHD. Modulation of methylation status of CYP2R1, CYP24A1 and VDR in response to plasma 25(OHD may be part of feedback loops involved in maintaining vitamin D homeostasis, and may explain a portion of the variance in plasma 25(OHD levels in response to intake and sun exposure. Methyl-group donor biochemistry, while a potential independent modulator, did not alter this effect.

Methylation screening of the TGFBI promoter in human lung and prostate cancer by methylation-specific PCR

International Nuclear Information System (INIS)

Shah, Jinesh N; Shao, Genze; Hei, Tom K; Zhao, Yongliang

2008-01-01

Hypermethylation of the TGFBI promoter has been shown to correlate with decreased expression of this gene in human tumor cell lines. In this study, we optimized a methylation-specific polymerase chain reaction (MSP) method and investigated the methylation status of the TGFBI promoter in human lung and prostate cancer specimens. Methylation-specific primers were designed based on the methylation profiles of the TGFBI promoter in human tumor cell lines, and MSP conditions were optimized for accurate and efficient amplification. Genomic DNA was isolated from lung tumors and prostatectomy tissues of prostate cancer patients, bisulfite-converted, and analyzed by MSP. Among 50 lung cancer samples, 44.0% (22/50) harbored methylated CpG sites in the TGFBI promoter. An analysis correlating gene methylation status with clinicopathological cancer features revealed that dense methylation of the TGFBI promoter was associated with a metastatic phenotype, with 42.9% (6/14) of metastatic lung cancer samples demonstrating dense methylation vs. only 5.6% (2/36) of primary lung cancer samples (p < 0.05). Similar to these lung cancer results, 82.0% (41/50) of prostate cancer samples harbored methylated CpG sites in the TGFBI promoter, and dense methylation of the promoter was present in 38.9% (7/18) of prostate cancer samples with the feature of locoregional invasiveness vs. only 19.4% (6/31) of prostate cancer samples without locoregional invasiveness (p < 0.05). Furthermore, promoter hypermethylation correlated with highly reduced expression of the TGFBI gene in human lung and prostate tumor cell lines. We successfully optimized a MSP method for the precise and efficient screening of TGFBI promoter methylation status. Dense methylation of the TGFBI promoter correlated with the extent of TGFBI gene silencing in tumor cell lines and was related to invasiveness of prostate tumors and metastatic status of lung cancer tumors. Thus, TGFBI promoter methylation can be used as a potential

When, where and how the bridge breaks: anaphase bridge breakage plays a crucial role in gene amplification and HSR generation

International Nuclear Information System (INIS)

Shimizu, Noriaki; Shingaki, Kenta; Kaneko-Sasaguri, Yukiko; Hashizume, Toshihiko; Kanda, Teru

2005-01-01

Amplified genes are frequently localized on extrachromosomal double minutes (DMs) or in chromosomal homogenously staining regions (HSRs). We previously showed that a plasmid bearing a mammalian replication initiation region could efficiently generate DMs and HSRs after transfection into human tumor cell lines. The Breakage-Fusion-Bridge (BFB) cycle model, a classical model that explains how HSRs form, could also be used to explain how the transfected plasmids generate HSRs. The BFB cycle model involves anaphase bridge formation due to the presence of dicentric chromosomes, followed by the breakage of the bridge. In this study, we used our plasmid-based model system to analyze how anaphase bridges break during mitosis. Dual-color fluorescence in situ hybridization analyses revealed that anaphase bridges were most frequently severed in their middle irrespective of their lengths, which suggests that a structurally fragile site exists in the middle of the anaphase bridge. Breakage of the chromosomal bridges occurred prior to nuclear membrane reformation and the completion of cytokinesis, which indicates that mechanical tension rather than cytokinesis is primarily responsible for severing anaphase bridges. Time-lapse observation of living cells revealed that the bridges rapidly shrink after being severed. If HSR length was extended too far, the bridge could no longer be resolved and became tangled depending on the tension. The unbroken bridge appeared to inhibit the completion of cytokinesis. These observations strongly suggest that anaphase bridges are highly elastic and that the length of the spindle axis determines the maximal HSR length

A DNA methylation microarray-based study identifies ERG as a gene commonly methylated in prostate cancer.

Science.gov (United States)

Schwartzman, Jacob; Mongoue-Tchokote, Solange; Gibbs, Angela; Gao, Lina; Corless, Christopher L; Jin, Jennifer; Zarour, Luai; Higano, Celestia; True, Lawrence D; Vessella, Robert L; Wilmot, Beth; Bottomly, Daniel; McWeeney, Shannon K; Bova, G Steven; Partin, Alan W; Mori, Motomi; Alumkal, Joshi

2011-10-01

DNA methylation of promoter regions is a common event in prostate cancer, one of the most common cancers in men worldwide. Because prior reports demonstrating that DNA methylation is important in prostate cancer studied a limited number of genes, we systematically quantified the DNA methylation status of 1505 CpG dinucleotides for 807 genes in 78 paraffin-embedded prostate cancer samples and three normal prostate samples. The ERG gene, commonly repressed in prostate cells in the absence of an oncogenic fusion to the TMPRSS2 gene, was one of the most commonly methylated genes, occurring in 74% of prostate cancer specimens. In an independent group of patient samples, we confirmed that ERG DNA methylation was common, occurring in 57% of specimens, and cancer-specific. The ERG promoter is marked by repressive chromatin marks mediated by polycomb proteins in both normal prostate cells and prostate cancer cells, which may explain ERG's predisposition to DNA methylation and the fact that tumors with ERG DNA methylation were more methylated, in general. These results demonstrate that bead arrays offer a high-throughput method to discover novel genes with promoter DNA methylation such as ERG, whose measurement may improve our ability to more accurately detect prostate cancer.

DNA methylation and memory formation.

Science.gov (United States)

Day, Jeremy J; Sweatt, J David

2010-11-01

Memory formation and storage require long-lasting changes in memory-related neuronal circuits. Recent evidence indicates that DNA methylation may serve as a contributing mechanism in memory formation and storage. These emerging findings suggest a role for an epigenetic mechanism in learning and long-term memory maintenance and raise apparent conundrums and questions. For example, it is unclear how DNA methylation might be reversed during the formation of a memory, how changes in DNA methylation alter neuronal function to promote memory formation, and how DNA methylation patterns differ between neuronal structures to enable both consolidation and storage of memories. Here we evaluate the existing evidence supporting a role for DNA methylation in memory, discuss how DNA methylation may affect genetic and neuronal function to contribute to behavior, propose several future directions for the emerging subfield of neuroepigenetics, and begin to address some of the broader implications of this work.

HOLOGRAPHIC GRATING RECORDING IN “LYOTROPIC LIQUID CRYSTAL – VIOLOGEN” SYSTEM

Directory of Open Access Journals (Sweden)

Hanna Bordyuh

2013-12-01

Full Text Available This work presents the results of nonlinear optical experiment run on the samples of lyotropic liquid crystal (LLC with viologen admixtures. During the experiment we obtained dynamic grating recording on bilayered LLC-viologen samples and determined main characteristics of recoded gratings. It was found out that the recording takes place in a thin near-cathode coloured viologen layer. The analysis of kinetics of thermal gratings erasing showed that contribution of a thermal nonlinearity into general diffraction efficiency is negligible small. The last fact is connected with a separation of LLC-viologen samples under the action of an electric field and heat sink into the liquid crystal layer

33 CFR 118.70 - Lights on swing bridges.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on swing bridges. 118.70 Section 118.70 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.70 Lights on swing bridges. (a) Swing span lights on through bridges. Each...

33 CFR 118.65 - Lights on fixed bridges.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on fixed bridges. 118.65 Section 118.65 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.65 Lights on fixed bridges. (a) Each fixed bridge span over a navigable...

23 CFR 650.409 - Evaluation of bridge inventory.

Science.gov (United States)

2010-04-01

... 23 Highways 1 2010-04-01 2010-04-01 false Evaluation of bridge inventory. 650.409 Section 650.409... Evaluation of bridge inventory. (a) Sufficiency rating of bridges. Upon receipt and evaluation of the bridge inventory, a sufficiency rating will be assigned to each bridge by the Secretary in accordance with the...

Effects of Electrolyte on Floating Water Bridge

OpenAIRE

Hideo Nishiumi; Fumitaka Honda

2009-01-01

Fuchs found phenomena that when high voltage is applied to deionized water filled in two contacted beakers, a floating water bridge forms spontaneously. In this paper, we examined flow direction of water bridge and what effects the addition of electrolytes such as NaCl, NaOH, and N H 4 C l to the floating water bridge would give. We found that ionization degree reduced the length of water bridge though insoluble electrolyte A l 2 O 3 had no effect on the length of water bridge.

Ligand-based photooxidations of dithiomaltolato complexes of Ru(II) and Zn(II): photolytic CH activation and evidence of singlet oxygen generation and quenching.

Science.gov (United States)

Bruner, Britain; Walker, Malin Backlund; Ghimire, Mukunda M; Zhang, Dong; Selke, Matthias; Klausmeyer, Kevin K; Omary, Mohammad A; Farmer, Patrick J

2014-08-14

The complex [Ru(bpy)2(ttma)](+) (bpy = 2,2'-bipyridine; ttma = 3-hydroxy-2-methyl-thiopyran-4-thionate, 1, has previously been shown to undergo an unusual C-H activation of the dithiomaltolato ligand upon outer-sphere oxidation. The reaction generated alcohol and aldehyde products 2 and 3 from C-H oxidation of the pendant methyl group. In this report, we demonstrate that the same products are formed upon photolysis of 1 in presence of mild oxidants such as methyl viologen, [Ru(NH3)6](3+) and [Co(NH3)5Cl](2+), which do not oxidize 1 in the dark. This reactivity is engendered only upon excitation into an absorption band attributed to the ttma ligand. Analogous experiments with the homoleptic Zn(ttma)2, 4, also result in reduction of electron acceptors upon excitation of the ttma absorption band. Complexes 1 and 4 exhibit short-lived visible fluorescence and long-lived near-infrared phosphorescence bands. Singlet oxygen is both generated and quenched during aerobic excitation of 1 or 4, but is not involved in the C-H activation process.

A data management infrastructure for bridge monitoring

Science.gov (United States)

Jeong, Seongwoon; Byun, Jaewook; Kim, Daeyoung; Sohn, Hoon; Bae, In Hwan; Law, Kincho H.

2015-04-01

This paper discusses a data management infrastructure framework for bridge monitoring applications. As sensor technologies mature and become economically affordable, their deployment for bridge monitoring will continue to grow. Data management becomes a critical issue not only for storing the sensor data but also for integrating with the bridge model to support other functions, such as management, maintenance and inspection. The focus of this study is on the effective data management of bridge information and sensor data, which is crucial to structural health monitoring and life cycle management of bridge structures. We review the state-of-the-art of bridge information modeling and sensor data management, and propose a data management framework for bridge monitoring based on NoSQL database technologies that have been shown useful in handling high volume, time-series data and to flexibly deal with unstructured data schema. Specifically, Apache Cassandra and Mongo DB are deployed for the prototype implementation of the framework. This paper describes the database design for an XML-based Bridge Information Modeling (BrIM) schema, and the representation of sensor data using Sensor Model Language (SensorML). The proposed prototype data management framework is validated using data collected from the Yeongjong Bridge in Incheon, Korea.

Railway bridge monitoring during construction and sliding

Science.gov (United States)

Inaudi, Daniele; Casanova, Nicoletta; Kronenberg, Pascal; Vurpillot, Samuel

1997-05-01

The Moesa railway bridge is a composite steel concrete bridge on three spans of 30 m each. The 50 cm thick concrete deck is supported on the lower flanges of two continuous, 2.7 m high I-beams. The bridge has been constructed alongside an old metallic bridge. After demolishing this one, the new bridge has been slid for 5 m by 4 hydraulic jacks and positioned on the refurbished piles of the old bridge. About 30 fiber optic, low-coherence sensors were imbedded in the concrete deck to monitor its deformations during concrete setting and shrinkage, as well as during the bridge sliding phase. In the days following concrete pour it was possible to follow its thermal expansion due to the exothermic setting reaction and the following thermal and during shrinkage. The deformations induced by the additional load produced by the successive concreting phases were also observed. During the bridge push, which extended over six hours, the embedded and surface mounted sensors allowed the monitoring of the curvature variations in the horizontal plane due to the slightly uneven progression of the jacks. Excessive curvature and the resulting cracking of concrete could be ruled out by these measurements. It was also possible to observe the bridge elongation under the heating action of the sun.

DNA methylation in metabolic disorders

DEFF Research Database (Denmark)

Barres, Romain; Zierath, Juleen R

2011-01-01

DNA methylation is a major epigenetic modification that controls gene expression in physiologic and pathologic states. Metabolic diseases such as diabetes and obesity are associated with profound alterations in gene expression that are caused by genetic and environmental factors. Recent reports...... have provided evidence that environmental factors at all ages could modify DNA methylation in somatic tissues, which suggests that DNA methylation is a more dynamic process than previously appreciated. Because of the importance of lifestyle factors in metabolic disorders, DNA methylation provides...... a mechanism by which environmental factors, including diet and exercise, can modify genetic predisposition to disease. This article considers the current evidence that defines a role for DNA methylation in metabolic disorders....

Histone Lysine Methylation and Neurodevelopmental Disorders

Directory of Open Access Journals (Sweden)

Jeong-Hoon Kim

2017-06-01

Full Text Available Methylation of several lysine residues of histones is a crucial mechanism for relatively long-term regulation of genomic activity. Recent molecular biological studies have demonstrated that the function of histone methylation is more diverse and complex than previously thought. Moreover, studies using newly available genomics techniques, such as exome sequencing, have identified an increasing number of histone lysine methylation-related genes as intellectual disability-associated genes, which highlights the importance of accurate control of histone methylation during neurogenesis. However, given the functional diversity and complexity of histone methylation within the cell, the study of the molecular basis of histone methylation-related neurodevelopmental disorders is currently still in its infancy. Here, we review the latest studies that revealed the pathological implications of alterations in histone methylation status in the context of various neurodevelopmental disorders and propose possible therapeutic application of epigenetic compounds regulating histone methylation status for the treatment of these diseases.

A reagent-assisted method in SERS detection of methyl salicylate

Science.gov (United States)

Li, Yali; Li, Qianwen; Wang, Yanan; Oh, Joohee; Jin, Sila; Park, Yeonju; Zhou, Tieli; Zhao, Bing; Ruan, Weidong; Jung, Young Mee

2018-04-01

With the explosive application of methyl salicylate (MS) molecules in food and cosmetics, the further detection of MS molecules becomes particularly important. Here we investigated the detection of MS molecules based on surface-enhanced Raman scattering (SERS) in a novel molecule/assistant/metal system constructed with MS, 4,4‧-(hexafluoroisopropylidene) bis (benzoic acid) and Ag nanoparticles (AgNPs). The minimum detection concentration is 10-4 M. To explore the function of assisted reagent, we also referred another system without assistant molecules. The result demonstrates that SERS signals were not acquired, which proves that the assistant molecules are critical for the capture of MS molecules. Two possible mechanisms of MS/assistant/AgNPs system were speculated through two patterns of hydrogen bonds. The linker molecules acted as the role of the bridge between metallic substrates and target molecules through the molecular recognition. This strategy is very beneficial to the expanding of MS detection techniques and other hydrogen bond based coupling detections with SERS.

Avocado and olive oil methyl esters

International Nuclear Information System (INIS)

Knothe, Gerhard

2013-01-01

Biodiesel, the mono-alkyl esters of vegetable oils, animal fats or other triacylglycerol-containing materials and an alternative to conventional petroleum-based diesel fuel, has been derived from a variety of feedstocks. Numerous feedstocks have been investigated as potential biodiesel sources, including commodity oils, however, the methyl esters of avocado and olive oil would likely be suitable as biodiesel fuel. In order to expand the database and comprehensive evaluation of the properties of vegetable oil esters, in this work the fuel-related properties of avocado and olive oil methyl esters, which exhibit similar fatty acid profiles including high oleic acid content, are determined. The cetane numbers of avocado oil methyl esters and olive oil methyl esters are relatively high, determined as 59.2 and 62.5, respectively, due to their elevated content of methyl oleate. Other properties are well within the ranges specified in biodiesel standards. The cloud points of both esters are slightly above 0 °C due to their content of saturated esters, especially methyl palmitate. Overall, avocado and olive oil yield methyl esters with fuel properties comparable to methyl esters from other commodity vegetable oils. The 1 H and 13 C NMR spectra of avocado and olive oil methyl esters are reported. -- Highlights: • Methyl esters of avocado and olive oil meet biodiesel fuel standards. • Provides comparison for methyl esters of other vegetable oils with high oleic content. • Discusses and compares present results with prior literature

On the effect of nuclear bridge modes on donor-acceptor electronic coupling in donor-bridge-acceptor molecules

International Nuclear Information System (INIS)

Davis, Daly; Toroker, Maytal Caspary; Speiser, Shammai; Peskin, Uri

2009-01-01

We report a theoretical study of intra-molecular electronic coupling in a symmetric DBA (donor-bridge-acceptor) complex, in which a donor electronic site is coupled to an acceptor site by way of intervening orbitals of a molecular bridge unit. In the off-resonant (deep tunneling) regime of electronic transport, the lowest unoccupied molecular orbitals (MO's) of the DBA system are split into distinguishable donor/acceptor and bridge orbitals. The effect of geometrical changes at the bridge on the donor/acceptor electronic energy manifold is studied for local stretching and bending modes. It is demonstrated that the energy splitting in the manifold of donor/acceptor unoccupied MOs changes in response to such changes, as assumed in simple McConnell-type models. Limitations of the simple models are revealed where the electronic charging of the bridge orbitals correlates with increasing donor/acceptor orbital energy splitting only for stretching but not for bending bridge modes.

IceBridge Mission Flight Reports

Data.gov (United States)

National Aeronautics and Space Administration — The IceBridge Mission Flight Reports data set contains flight reports from NASA Operation IceBridge Greenland, Arctic, Antarctic, and Alaska missions. Flight reports...

Bridges analysis, design, structural health monitoring, and rehabilitation

CERN Document Server

Bakht, Baidar

2015-01-01

This book offers a valuable guide for practicing bridge engineers and graduate students in structural engineering; its main purpose is to present the latest concepts in bridge engineering in fairly easy-to-follow terms. The book provides details of easy-to-use computer programs for: ·      Analysing slab-on-girder bridges for live load distribution. ·      Analysing slab and other solid bridge components for live load distribution. ·      Analysing and designing concrete deck slab overhangs of girder bridges under vehicular loads. ·      Determining the failure loads of concrete deck slabs of girder bridges under concentrated wheel loads. In addition, the book includes extensive chapters dealing with the design of wood bridges and soil-steel bridges. Further, a unique chapter on structural health monitoring (SHM) will help bridge engineers determine the actual load carrying capacities of bridges, as opposed to their perceived analytical capacities. The chapter addressing structures...

Virtual Bridge Design Challenge

Science.gov (United States)

Mitts, Charles R.

2013-01-01

This design/problem-solving activity challenges students to design a replacement bridge for one that has been designated as either structurally deficient or functionally obsolete. The Aycock MS Technology/STEM Magnet Program Virtual Bridge Design Challenge is an authentic introduction to the engineering design process. It is a socially relevant…

The floating water bridge

International Nuclear Information System (INIS)

Fuchs, Elmar C; Woisetschlaeger, Jakob; Gatterer, Karl; Maier, Eugen; Pecnik, Rene; Holler, Gert; Eisenkoelbl, Helmut

2007-01-01

When high voltage is applied to distilled water filled in two glass beakers which are in contact, a stable water connection forms spontaneously, giving the impression of a floating water bridge. A detailed experimental analysis reveals static and dynamic structures as well as heat and mass transfer through this bridge

An orthogonal ferromagnetically coupled tetracopper(II) 2 x 2 homoleptic grid supported by micro-O4 bridges and its DFT study.

Science.gov (United States)

Roy, Somnath; Mandal, Tarak Nath; Barik, Anil Kumar; Pal, Sachindranath; Butcher, Ray J; El Fallah, Mohamed Salah; Tercero, Javier; Kar, Susanta Kumar

2007-03-28

A pyrazole based ditopic ligand (PzOAP), prepared by the reaction between 5-methylpyrazole-3-carbohydrazide and methyl ester of imino picolinic acid, reacts with Cu(NO3)2.6H2O to form a self-assembled, ferromagnetically coupled, alkoxide bridged tetranuclear homoleptic Cu(II) square grid-complex [Cu4(PzOAP)4(NO3)2] (NO3)2.4H2O (1) with a central Cu4[micro-O4] core, involving four ligand molecules. In the Cu4[micro-O4] core, out of four copper centers, two copper centers are penta-coordinated and the remaining two are hexa-coordinated. In each case of hexa-coordination, the sixth position is occupied by the nitrate ion. The complex 1 has been characterized structurally and magnetically. Although Cu-O-Cu bridge angles are too large (138-141 degrees) and Cu-Cu distances are short (4.043-4.131 A), suitable for propagation of expected antiferromagnetic exchange interactions within the grid, yet intramolecular ferromagnetic exchange (J = 5.38 cm(-1)) is present with S = 4/2 magnetic ground state. This ferromagnetic interaction is quite obvious from the bridging connections (d(x2-y2)) lying almost orthogonally between the metal centers. The exchange pathways parameters have been evaluated from density functional calculations.

MODERN ASPECTS OF BRIDGES MONITORING

Directory of Open Access Journals (Sweden)

M. I. Kazakevych

2007-12-01

Full Text Available The major concepts of the elaboration and realization of the bridge construction monitoring systemic approach are presented in this paper. The main peculiarity of the bridge monitoring modern aspect is pointed out here, namely, the transition from the demands of providing the reliability to the demands of providing the whole complex of the structure consumer qualities. The criteria of diagnostics of the bridge exploitation reliability as the fundamental aim of monitoring are formulated here.

75 FR 62181 - Annual Materials Report on New Bridge Construction and Bridge Rehabilitation

Science.gov (United States)

2010-10-07

... INFORMATION CONTACT: Ms. Ann Shemaka, Office of Bridge Technology, HIBT-30, (202) 366-1575, or Mr. Thomas Everett, Office of Bridge Technology, HIBT-30, (202) 366-4675, Federal Highway Administration, 1200 New... is categorized by the following material types, which are identified in the NBI: steel, concrete, pre...

77 FR 53251 - Annual Materials Report on New Bridge Construction and Bridge Rehabilitation

Science.gov (United States)

2012-08-31

... INFORMATION CONTACT: Ms. Ann Shemaka, Office of Bridge Technology, (202) 366-1575, or via email at [email protected] or Mr. Thomas Everett, Office of Bridge Technology, (202) 366-4675, or via email at thomas... the NBI: steel, concrete, pre-stressed concrete, and other. The category ``other'' includes wood...

76 FR 55160 - Annual Materials Report on New Bridge Construction and Bridge Rehabilitation

Science.gov (United States)

2011-09-06

... INFORMATION CONTACT: Ms. Ann Shemaka, Office of Bridge Technology, HIBT-30, (202) 366-1575, or Mr. Thomas Everett, Office of Bridge Technology, HIBT-30, (202) 366-4675, Federal Highway Administration, 1200 New... is categorized by the following material types, which are identified in the NBI: steel, concrete, pre...

Methylated site display (MSD)-AFLP, a sensitive and affordable method for analysis of CpG methylation profiles.

Science.gov (United States)

Aiba, Toshiki; Saito, Toshiyuki; Hayashi, Akiko; Sato, Shinji; Yunokawa, Harunobu; Maruyama, Toru; Fujibuchi, Wataru; Kurita, Hisaka; Tohyama, Chiharu; Ohsako, Seiichiroh

2017-03-09

It has been pointed out that environmental factors or chemicals can cause diseases that are developmental in origin. To detect abnormal epigenetic alterations in DNA methylation, convenient and cost-effective methods are required for such research, in which multiple samples are processed simultaneously. We here present methylated site display (MSD), a unique technique for the preparation of DNA libraries. By combining it with amplified fragment length polymorphism (AFLP) analysis, we developed a new method, MSD-AFLP. Methylated site display libraries consist of only DNAs derived from DNA fragments that are CpG methylated at the 5' end in the original genomic DNA sample. To test the effectiveness of this method, CpG methylation levels in liver, kidney, and hippocampal tissues of mice were compared to examine if MSD-AFLP can detect subtle differences in the levels of tissue-specific differentially methylated CpGs. As a result, many CpG sites suspected to be tissue-specific differentially methylated were detected. Nucleotide sequences adjacent to these methyl-CpG sites were identified and we determined the methylation level by methylation-sensitive restriction endonuclease (MSRE)-PCR analysis to confirm the accuracy of AFLP analysis. The differences of the methylation level among tissues were almost identical among these methods. By MSD-AFLP analysis, we detected many CpGs showing less than 5% statistically significant tissue-specific difference and less than 10% degree of variability. Additionally, MSD-AFLP analysis could be used to identify CpG methylation sites in other organisms including humans. MSD-AFLP analysis can potentially be used to measure slight changes in CpG methylation level. Regarding the remarkable precision, sensitivity, and throughput of MSD-AFLP analysis studies, this method will be advantageous in a variety of epigenetics-based research.

Prosthetic rehabilitation using adhesive bridge and fixed-fixed bridge on the maxilla and telescopic crown overdenture on mandible

Directory of Open Access Journals (Sweden)

Indah Sulistiawaty

2016-12-01

Full Text Available Prosthetic rehabilitation is the rehabilitation process of masticatory and esthetics function for patients missing teeth and alveolar bone by means of manufacture and installation of dentures. The prosthetic rehabilitation commonly used include denture adhesive bridge, fixed-fixed bridge, as well as telescopic overdenture. Adhesive bridge is bridge denture consisting of single pontic and two retainer wings attached to the abutment using cement or resin. Fixed-fixed bridge is a bridge denture with rigid connectors on both ends of the pontics, whereas the telescopic crown Overdenture is a removable denture that uses linked precision on the original tooth in the form of primary coping on abutment and secondary coping on the denture. To expose the procedures of prosthetic rehabilitation using adhesive bridge and fixed-fixed bridge on the maxilla and telescopic crown Overdenture on mandible. Male patients aged 32 years came with complaints of difficulty to chew food because he had lost some teeth behind. In the maxilla, teeth are lost in the region of 15 and 16 performed by making the fixed-fixed bridge with abutment teeth 14 and 17. Loss of teeth in the region of 26, performed the manufacture of adhesive bridge with a box preparation on the occlusal 25 and 27. In the mandible, tooth loss in the region of 36,37,46, and 47 performed manufacture of telescopic crown Overdenture with primer coping on the teeth 35.38, 45, and 48 and the secondary coping on a metal frame. Prosthetic rehabilitation especially in the case of loss of back teeth is very important because with the denture patients can chew properly and maintain the stomatognathic system.

Remediation: Higher Education's Bridge to Nowhere

Science.gov (United States)

Complete College America, 2012

2012-01-01

The intentions were noble. It was hoped that remediation programs would be an academic bridge from poor high school preparation to college readiness. Sadly, remediation has become instead higher education's "Bridge to Nowhere." This broken remedial bridge is travelled by some 1.7 million beginning students each year, most of whom will…

Effects of Electrolyte on Floating Water Bridge

Directory of Open Access Journals (Sweden)

Hideo Nishiumi

2009-01-01

spontaneously. In this paper, we examined flow direction of water bridge and what effects the addition of electrolytes such as NaCl, NaOH, and NH4Cl to the floating water bridge would give. We found that ionization degree reduced the length of water bridge though insoluble electrolyte Al2O3 had no effect on the length of water bridge.

Methylation-sensitive amplified polymorphism-based genome-wide analysis of cytosine methylation profiles in Nicotiana tabacum cultivars.

Science.gov (United States)

Jiao, J; Wu, J; Lv, Z; Sun, C; Gao, L; Yan, X; Cui, L; Tang, Z; Yan, B; Jia, Y

2015-11-26

This study aimed to investigate cytosine methylation profiles in different tobacco (Nicotiana tabacum) cultivars grown in China. Methylation-sensitive amplified polymorphism was used to analyze genome-wide global methylation profiles in four tobacco cultivars (Yunyan 85, NC89, K326, and Yunyan 87). Amplicons with methylated C motifs were cloned by reamplified polymerase chain reaction, sequenced, and analyzed. The results show that geographical location had a greater effect on methylation patterns in the tobacco genome than did sampling time. Analysis of the CG dinucleotide distribution in methylation-sensitive polymorphic restriction fragments suggested that a CpG dinucleotide cluster-enriched area is a possible site of cytosine methylation in the tobacco genome. The sequence alignments of the Nia1 gene (that encodes nitrate reductase) in Yunyan 87 in different regions indicate that a C-T transition might be responsible for the tobacco phenotype. T-C nucleotide replacement might also be responsible for the tobacco phenotype and may be influenced by geographical location.

DNA methylation in sugarcane somaclonal variants assessed through methylation-sensitive amplified polymorphism.

Science.gov (United States)

Francischini, J H M B; Kemper, E L; Costa, J B; Manechini, J R V; Pinto, L R

2017-05-04

Micropropagation is an important tool for large-scale multiplication of plant superior genotypes. However, somaclonal variation is one of the drawbacks of this process. Changes in DNA methylation have been widely reported as one of the main causes of somaclonal variations in plants. In order to investigate the occurrence of changes in the methylation pattern of sugarcane somaclonal variants, the MSAP (methylation-sensitive amplified polymorphism) technique was applied to micro-propagated plantlets sampled at the third subculture phase. The mother plant, in vitro normal plantlets, and in vitro abnormal plantlets (somaclonal variants) of four sugarcane clones were screened against 16 MSAP selective primers for EcoRI/MspI and EcoRI/HpaII restriction enzymes. A total of 1005 and 1200 MSAP-derived markers with polymorphism percentages of 28.36 and 40.67 were obtained for EcoRI/HpaII and EcoRI/MspI restriction enzyme combinations, respectively. The genetic similarity between the mother plant and the somaclonal variants ranged from 0.877 to 0.911 (EcoRI/MspI) and from 0.928 to 0.955 (EcoRI/HpaII). Most of the MASPs among mother plant and micro-propagated plantlets were derived from EcoRI/MspI restriction enzymes suggesting alteration due to gain or loss of internal cytosine methylation. A higher rate of loss of methylation (hypomethylation) than gain of methylation (hypermethylation) was observed in the abnormal in vitro sugarcane plantlets. Although changes in the methylation pattern were also observed in the in vitro normal plantlets, they were lower than those observed for the in vitro abnormal plantlets. The MASP technique proved to be a promising tool to early assessment of genetic fidelity of micro-propagated sugarcane plants.

Comparative Evaluation of Flexural Strength of Provisional Crown and Bridge Materials-An Invitro Study.

Science.gov (United States)

Singh, Ankita; Garg, Sandeep

2016-08-01

Provisional restorations serve a key role as a functional and esthetic try-in for the design of the final prosthesis. During selection of materials for this restoration, clinicians must consider physical properties, ease of handling, cost and patient satisfaction and approval. To evaluate and compare the flexural strength of provisional crown and bridge materials available commercially. This in-vitro study was done to compare the flexural strength of six temporary crown and bridge materials available commercially at 24 hours, 8 days and after repair. Three poly methyl methacrylate based materials (DPI, SC10 and Trulon) and three bis-acrylic based composite resins (Protemp, Cooltemp and Luxatemp) were selected. A total of 72 specimens of dimensions 64mm×10mm×2.5mm were prepared from these materials (12 from each material) and divided into two groups (n=36). Specimens were stored in artificial saliva and were fractured after 24 hours and 8 days using Universal Testing Machine. The fractured samples from the 8 days study were then subjected to repair. A uniform space of 2mm and a 450 bevel was maintained for all the repaired samples for better distribution of forces. Flexural strength of these repaired samples was recorded using the same machine. RESULTs were recorded and statistically analysed by one-way Anova and Post hoc tests. RESULTs revealed that there was decrease in flexural strength for all the materials tested from 24 hours to 8 days, though flexural strength between poly methyl methacrylate and bis-acrylic resins was similar at 24 hours and 8 days time interval. A substantial decrease was noticed in the strength of bis-acrylic composite resins after repair. From the current study it can be suggested that though there is decrease in flexural strength for all the materials from 24 hours to 8 days, both can be used to fabricate the provisional restorations. However, in the event of a fracture of a bis-acrylic provisional restoration, it may be more

LIGHT BRIDGE IN A DEVELOPING ACTIVE REGION. II. NUMERICAL SIMULATION OF FLUX EMERGENCE AND LIGHT BRIDGE FORMATION

International Nuclear Information System (INIS)

Toriumi, Shin; Katsukawa, Yukio; Cheung, Mark C. M.

2015-01-01

Light bridges, the bright structure dividing umbrae in sunspot regions, show various activity events. In Paper I, we reported on an analysis of multi-wavelength observations of a light bridge in a developing active region (AR) and concluded that the activity events are caused by magnetic reconnection driven by magnetconvective evolution. The aim of this second paper is to investigate the detailed magnetic and velocity structures and the formation mechanism of light bridges. For this purpose, we analyze numerical simulation data from a radiative magnetohydrodynamics model of an emerging AR. We find that a weakly magnetized plasma upflow in the near-surface layers of the convection zone is entrained between the emerging magnetic bundles that appear as pores at the solar surface. This convective upflow continuously transports horizontal fields to the surface layer and creates a light bridge structure. Due to the magnetic shear between the horizontal fields of the bridge and the vertical fields of the ambient pores, an elongated cusp-shaped current layer is formed above the bridge, which may be favorable for magnetic reconnection. The striking correspondence between the observational results of Paper I and the numerical results of this paper provides a consistent physical picture of light bridges. The dynamic activity phenomena occur as a natural result of the bridge formation and its convective nature, which has much in common with those of umbral dots and penumbral filaments

Optimum Maintenance Strategies for Highway Bridges

DEFF Research Database (Denmark)

Frangopol, Dan M.; Thoft-Christensen, Palle; Das, Parag C.

As bridges become older and maintenance costs become higher, transportation agencies are facing challenges related to implementation of optimal bridge management programs based on life cycle cost considerations. A reliability-based approach is necessary to find optimal solutions based on minimum...... expected life-cycle costs or maximum life-cycle benefits. This is because many maintenance activities can be associated with significant costs, but their effects on bridge safety can be minor. In this paper, the program of an investigation on optimum maintenance strategies for different bridge types...... is described. The end result of this investigation will be a general reliability-based framework to be used by the UK Highways Agency in order to plan optimal strategies for the maintenance of its bridge network so as to optimize whole-life costs....

Investigation of Aerodynamic Interference between Twin Deck Bridges

Energy Technology Data Exchange (ETDEWEB)

Sitek, M. A. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division. Transportation Research and Analysis Computing Center (TRACC); Bojanowski, C. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division. Transportation Research and Analysis Computing Center (TRACC); Lottes, S. A. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division. Transportation Research and Analysis Computing Center (TRACC)

2016-05-01

Construction of a twin bridge can be a cost effective and minimally disruptive way to increase capacity when an existing bridge is not near the end of its service life. With ever growing vehicular traffic, when demand approaches the capacity of many existing roads and bridges. Remodeling a structure with an insufficient number of lanes can be a good solution in case of smaller and less busy bridges. Closing down or reducing traffic on crossings of greater importance for the construction period, however, can result in major delays and revenue loss for commerce and transportation as well as increasing the traffic load on alternate route bridges. Multiple-deck bridges may be the answer to this issue. A parallel deck can be built next to the existing one, without reducing the flow. Additionally, a new bridge can be designed as a twin or multi-deck structure. Several such structures have been built throughout the United States, among them: - The New NY Bridge Project - the Tappan Zee Hudson River Crossing, - SR-182 Columbia River Bridge, - The Thaddeus Kosciusko Bridge (I-87), - The Allegheny River Bridge, Pennsylvania, which carries I76, - Fred Hartman Bridge, TX, see Figure 1.2. With a growing number of double deck bridges, additional, more detailed, studies on the interaction of such bridge pairs in windy conditions appears appropriate. Aerodynamic interference effects should be examined to assure the aerodynamic stability of both bridges. There are many studies on aerodynamic response of single deck bridges, but the literature on double-deck structures is not extensive. The experimental results from wind tunnels are still limited in number, as a parametric study is required, they can be very time consuming. Literature review shows that some investigation of the effects of gap-width and angle of wind incidence has been done. Most of the CFD computational studies that have been done were limited to 2D simulations. Therefore, it is desirable to investigate twin decks

Genome-wide methylation analysis identifies differentially methylated CpG loci associated with severe obesity in childhood.

Science.gov (United States)

Huang, R C; Garratt, E S; Pan, H; Wu, Y; Davis, E A; Barton, S J; Burdge, G C; Godfrey, K M; Holbrook, J D; Lillycrop, K A

2015-01-01

Childhood obesity is a major public health issue. Here we investigated whether differential DNA methylation was associated with childhood obesity. We studied DNA methylation profiles in whole blood from 78 obese children (mean BMI Z-score: 2.6) and 71 age- and sex-matched controls (mean BMI Z-score: 0.1). DNA samples from obese and control groups were pooled and analyzed using the Infinium HumanMethylation450 BeadChip array. Comparison of the methylation profiles between obese and control subjects revealed 129 differentially methylated CpG (DMCpG) loci associated with 80 unique genes that had a greater than 10% difference in methylation (P-value obesity were validated using sodium bisulfite pyrosequencing across loci within the FYN, PIWIL4, and TAOK3 genes in individual subjects. Three CpG loci within FYN were hypermethylated in obese individuals (all P obesity was associated with lower methylation of CpG loci within PIWIL4 (P = 0.003) and TAOK3 (P = 0.001). After building logistic regression models, we determined that a 1% increase in methylation in TAOK3, multiplicatively decreased the odds of being obese by 0.91 (95% CI: 0.86 - 0.97), and an increase of 1% methylation in FYN CpG3, multiplicatively increased the odds of being obese by 1.03 (95% CI: 0.99 - 1.07). In conclusion, these findings provide evidence that childhood obesity is associated with specific DNA methylation changes in whole blood, which may have utility as biomarkers of obesity risk.

Review of Energy Harvesters Utilizing Bridge Vibrations

Directory of Open Access Journals (Sweden)

Farid Ullah Khan

2016-01-01

Full Text Available For health monitoring of bridges, wireless acceleration sensor nodes (WASNs are normally used. In bridge environment, several forms of energy are available for operating WASNs that include wind, solar, acoustic, and vibration energy. However, only bridge vibration has the tendency to be utilized for embedded WASNs application in bridge structures. This paper reports on the recent advancements in the area of vibration energy harvesters (VEHs utilizing bridge oscillations. The bridge vibration is narrowband (1 to 40 Hz with low acceleration levels (0.01 to 3.8 g. For utilization of bridge vibration, electromagnetic based vibration energy harvesters (EM-VEHs and piezoelectric based vibration energy harvesters (PE-VEHs have been developed. The power generation of the reported EM-VEHs is in the range from 0.7 to 1450000 μW. However, the power production by the developed PE-VEHs ranges from 0.6 to 7700 μW. The overall size of most of the bridge VEHs is quite comparable and is in mesoscale. The resonant frequencies of EM-VEHs are on the lower side (0.13 to 27 Hz in comparison to PE-VEHs (1 to 120 Hz. The power densities reported for these bridge VEHs range from 0.01 to 9539.5 μW/cm3 and are quite enough to operate most of the commercial WASNs.

Fatigue Testing of Dental Bridges on Selected Examples

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Urban Dariusz

2017-03-01

Full Text Available The paper presents example tests of the functional quality of selected designs of dental bridges. These were: porcelain bridges on a metal base (cobalt based alloy, porcelain bridges on a zirconia base (zirconia ceramic – Zirkon Zahn, and full zirconia bridges (Zirkon Zahn. For the purpose of the study, durability of bridges in cyclic fatigue testing was adopted as a measure of their quality. The tests were carried out on a Zwick Roell Z010 universal testing machine. They consisted in cyclic loading and unloading of dental bridges mounted on gypsum models at a loading force of F= 400 [N] and a frequency of load of f= 1 [Hz]. Each bridge was subjected to a cycle of 7200 loads. The results show that there are no significant differences in the functional quality of the bridges.

Vehicle - Bridge interaction, comparison of two computing models

Science.gov (United States)

Melcer, Jozef; Kuchárová, Daniela

2017-07-01

The paper presents the calculation of the bridge response on the effect of moving vehicle moves along the bridge with various velocities. The multi-body plane computing model of vehicle is adopted. The bridge computing models are created in two variants. One computing model represents the bridge as the Bernoulli-Euler beam with continuously distributed mass and the second one represents the bridge as the lumped mass model with 1 degrees of freedom. The mid-span bridge dynamic deflections are calculated for both computing models. The results are mutually compared and quantitative evaluated.

Seismic Passive Control of Cable-Stayed Bridges

Directory of Open Access Journals (Sweden)

Hosam-Eddin M. Ali

1995-01-01

Full Text Available A three-dimensional modeling procedure is proposed for cable-stayed bridges with rubber, steel, and lead energy dissipation devices. The passive control technique is investigated by considering the response of bridge models with and without energy dissipation devices. The impact of various design parameters on the seismic response of current and future bridge designs is studied. Appropriate locations and properties of the passive devices can achieve better performance for cable-stayed bridges by balancing the significant reduction in earthquake-induced forces against tolerable displacements. Proper design of passive systems can help provide solutions for retro-fitting some existing bridges.

Istanbul Bridge Conference 2014

CERN Document Server

Gülkan, Polat; Mahmoud, Khaled

2016-01-01

  The book includes peer-reviewed contributions selected from presentations given at the Istanbul Bridge Conference 2014, held from August 11 – 13 in Istanbul, Turkey. It reports on the current challenges in bridge engineering faced by professionals around the globe, giving a special emphasis to recently developed techniques, innovations and opportunities. The book covers key topics in the field, including modeling and analysis methods; construction and erection techniques; design for extreme events and condition assessment and structural health monitoring. There is a balanced presentation of theory, research and practice. This book, which provides the readers with a comprehensive and timely reference guide on current practices in bridge engineering, is intended for professionals, academic researchers and students alike.

Analysis of RET promoter CpG island methylation using methylation-specific PCR (MSP), pyrosequencing, and methylation-sensitive high-resolution melting (MS-HRM): impact on stage II colon cancer patient outcome.

Science.gov (United States)

Draht, Muriel X G; Smits, Kim M; Jooste, Valérie; Tournier, Benjamin; Vervoort, Martijn; Ramaekers, Chantal; Chapusot, Caroline; Weijenberg, Matty P; van Engeland, Manon; Melotte, Veerle

2016-01-01

Already since the 1990s, promoter CpG island methylation markers have been considered promising diagnostic, prognostic, and predictive cancer biomarkers. However, so far, only a limited number of DNA methylation markers have been introduced into clinical practice. One reason why the vast majority of methylation markers do not translate into clinical applications is lack of independent validation of methylation markers, often caused by differences in methylation analysis techniques. We recently described RET promoter CpG island methylation as a potential prognostic marker in stage II colorectal cancer (CRC) patients of two independent series. In the current study, we analyzed the RET promoter CpG island methylation of 241 stage II colon cancer patients by direct methylation-specific PCR (MSP), nested-MSP, pyrosequencing, and methylation-sensitive high-resolution melting (MS-HRM). All primers were designed as close as possible to the same genomic region. In order to investigate the effect of different DNA methylation assays on patient outcome, we assessed the clinical sensitivity and specificity as well as the association of RET methylation with overall survival for three and five years of follow-up. Using direct-MSP and nested-MSP, 12.0 % (25/209) and 29.6 % (71/240) of the patients showed RET promoter CpG island methylation. Methylation frequencies detected by pyrosequencing were related to the threshold for positivity that defined RET methylation. Methylation frequencies obtained by pyrosequencing (threshold for positivity at 20 %) and MS-HRM were 13.3 % (32/240) and 13.8 % (33/239), respectively. The pyrosequencing threshold for positivity of 20 % showed the best correlation with MS-HRM and direct-MSP results. Nested-MSP detected RET promoter CpG island methylation in deceased patients with a higher sensitivity (33.1 %) compared to direct-MSP (10.7 %), pyrosequencing (14.4 %), and MS-HRM (15.4 %). While RET methylation frequencies detected by nested

A Polish approach to FRP bridges

Science.gov (United States)

Siwowski, Tomasz; Rajchel, Mateusz

2017-12-01

The paper presents initial results of a new approach to FRP composite bridge construction that is presently being developed and tested in Poland. The concept combines lightweight concrete with FRP composites to create a durable highly optimised structure. The paper describes the bridge system itself and presents the research results on its development. The basic design is presented together with research results on its development: FEM analysis and a range of static test results of full-scale bridge beam experiments. The paper finishes with some test results of a full scale bridge that was constructed near Rzeszow in December 2015.

Virginia Bridge Information Systems Laboratory.

Science.gov (United States)

2014-06-01

This report presents the results of applied data mining of legacy bridge databases, focusing on the Pontis and : National Bridge Inventory databases maintained by the Virginia Department of Transportation (VDOT). Data : analysis was performed using a...

Myrsinoic A acid and its derivative: in vitro inhibitors of photosynthesis; Acido myrsinoico A e derivado: inibidores da fotossintese in vitro

Energy Technology Data Exchange (ETDEWEB)

Burger, Marcela Carmen de M.; Oliveira, Gracielle S. de; Menezes, Antonio Carlos S [Universidade Estadual de Goias, Anapolis, GO (Brazil). Unidade Universitaria de Ciencias Exatas e Tecnologicas; Vieira, Paulo Cezar; Silva, Maria Fatima das G.F. da [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Dept. de Quimica; Veiga, Thiago A.M., E-mail: tveiga@unifesp.br [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil). Inst. de Ciencias Ambientais, Quimicas e Farmaceuticas. Dept. de Ciencias Exatas e da Terra

2012-07-01

Myrsinoic A acid, isolated from Myrsine cuneifolia and its hydrogenated derivative had their effect on photosynthesis tested. The compounds inhibited the electron flow (basal, phosphorylating and uncoupled) from water to methyl viologen; therefore, they act as Hill reaction inhibitors in spinach thylakoids. They inhibited partial reactions of PSII electron flow from water to 2,5-dichloro-1,4-benzoquinone, from water to sodium silicomolybdate, and partially electron flow from diphenylcarbazide to 2,6-dichloroindophenol. Their inhibition sites were at the donor and acceptor sides of PSII, between P{sub 680} and Q{sub A}. Chlorophyll {alpha} fluorescence measurements confirmed the behavior of the compounds (pool of quinones). (author)

Myrsinoic A acid and its derivative: in vitro inhibitors of photosynthesis

International Nuclear Information System (INIS)

Burger, Marcela Carmen de M.; Oliveira, Gracielle S. de; Menezes, Antonio Carlos S.; Vieira, Paulo Cezar; Silva, Maria Fatima das G.F. da; Veiga, Thiago A.M.

2012-01-01

Myrsinoic A acid, isolated from Myrsine cuneifolia and its hydrogenated derivative had their effect on photosynthesis tested. The compounds inhibited the electron flow (basal, phosphorylating and uncoupled) from water to methyl viologen; therefore, they act as Hill reaction inhibitors in spinach thylakoids. They inhibited partial reactions of PSII electron flow from water to 2,5-dichloro-1,4-benzoquinone, from water to sodium silicomolybdate, and partially electron flow from diphenylcarbazide to 2,6-dichloroindophenol. Their inhibition sites were at the donor and acceptor sides of PSII, between P 680 and Q A . Chlorophyll α fluorescence measurements confirmed the behavior of the compounds (pool of quinones). (author)

Photolytic and radiolytic studies of redox processes in aqueous solutions of acridine yellow

International Nuclear Information System (INIS)

Micic, O.I.; Nenadovic, M.T.

1981-01-01

Irradiation by visible light of an aqueous solution containing acridine yellow as a sensitizer and EDTA or cysteine as an electron donor leads to the formation of reduced species which can later reduce several different electron acceptors. Methyl viologen, europium(III) salicylate, europium(III) EDTA complex or vanadium(III) salicylate were used as electron acceptors. In the presence of a catalyst reduction of water is accompanied by the evolution of hydrogen. The kinetics and mechanism of redox reactions occurring in such a system have been explored by pulse radiolysis. Optimum conditions for water reduction under continuous illumination are analysed and implications for an energy conversion system discussed. (author)

Reliability Assessment of Concrete Bridges

DEFF Research Database (Denmark)

Thoft-Christensen, Palle; Middleton, C. R.

This paper is partly based on research performed for the Highways Agency, London, UK under the project DPU/9/44 "Revision of Bridge Assessment Rules Based on Whole Life Performance: concrete bridges". It contains the details of a methodology which can be used to generate Whole Life (WL) reliability...... profiles. These WL reliability profiles may be used to establish revised rules for concrete bridges. This paper is to some extend based on Thoft-Christensen et. al. [1996], Thoft-Christensen [1996] et. al. and Thoft-Christensen [1996]....

Complex Testing of the Bridges

Directory of Open Access Journals (Sweden)

Savić Adrijana

2016-01-01

Full Text Available This article describes the process of examining bridges. AB road bridge, founded on the columns by the Karpoš system and damaged due to erosive action of the river, is given as an example. The first tests of the bridge are conducted on the impact load of V 300, because of the appearance of longitudinal cracks. The results of the columns testing are presented in this paper, as well as the rehabilitation measures thus increasing the load capacity of the column.

Protection against de novo methylation is instrumental in maintaining parent-of-origin methylation inherited from the gametes.

Science.gov (United States)

Proudhon, Charlotte; Duffié, Rachel; Ajjan, Sophie; Cowley, Michael; Iranzo, Julian; Carbajosa, Guillermo; Saadeh, Heba; Holland, Michelle L; Oakey, Rebecca J; Rakyan, Vardhman K; Schulz, Reiner; Bourc'his, Déborah

2012-09-28

Identifying loci with parental differences in DNA methylation is key to unraveling parent-of-origin phenotypes. By conducting a MeDIP-Seq screen in maternal-methylation free postimplantation mouse embryos (Dnmt3L-/+), we demonstrate that maternal-specific methylation exists very scarcely at midgestation. We reveal two forms of oocyte-specific methylation inheritance: limited to preimplantation, or with longer duration, i.e. maternally imprinted loci. Transient and imprinted maternal germline DMRs (gDMRs) are indistinguishable in gametes and preimplantation embryos, however, de novo methylation of paternal alleles at implantation delineates their fates and acts as a major leveling factor of parent-inherited differences. We characterize two new imprinted gDMRs, at the Cdh15 and AK008011 loci, with tissue-specific imprinting loss, again by paternal methylation gain. Protection against demethylation after fertilization has been emphasized as instrumental in maintaining parent-of-origin methylation inherited from the gametes. Here we provide evidence that protection against de novo methylation acts as an equal major pivot, at implantation and throughout life. Copyright © 2012 Elsevier Inc. All rights reserved.

Final Environmental Assessment, Horse Creek Bridge Replacement

Science.gov (United States)

2010-10-01

existing bridge pipes that have failed and replace the failed structure with a new, prefabricated pedestrian bridge within the original bridge footprint...vehicles, nor designed for support of standard passenger vehicle loads. The bridge would be a single prefabricated unit consisting of a steel grate...placed on new concrete abutments built on the existing foundations on the creek banks, and put in place by a crane operating from the vehicle parking

Stabilizer for seismically exposed bridge cranes

International Nuclear Information System (INIS)

Engelke, M.; Kuhr, H.

1982-01-01

The invention concerns a stabilizer for seismically exposed bridge cranes in reactor buildings. The trolley and the crane bridge are fitted with the stabilizer consisting of a bipartite safety catch which is connected with a joint and able to take up the vertical loads during an earthquake. This stabilizer is suitable for all kinds of bridge cranes operated in seismically active regions

SURGERY OF SYMPTOMATIC MYOCARDIAL BRIDGING

Directory of Open Access Journals (Sweden)

N. Maghamipour N. Safaei

2007-06-01

Full Text Available Myocardial bridging with systolic compression of the left anterior descending coronary artery (LAD may be associated with myocardial ischemia. In symptomatic myocardial bridging unresponsive to medical treatment, surgical unroofing of the left LAD can be performed. Little information is available about the long-term prognosis of patients with this coronary anomaly after the surgical unroofing, so we decided to evaluate the result of this operation. A total of 26 patients underwent surgical unroofing of myocardial bridging. Patients had a myocardial bridge of at least 3 cm in length in the middle of LAD and with more than 70% compression during systole. Unroofing was performed with cardiopulmonary bypass in 16 and with off pump technique in 10 patients. In 6 patients repeat angiographies for control of myotomy were done. In one of them a nonsignificant 20% narrowing was seen. Postoperative scintigraphic and angiographic studies demonstrated restoration of coronary flow and myocardial perfusion without residual myocardial bridges under beta-stimulation in 24 patients. Two patients had residual narrowing. With off pump technique, 1 patient had perforation of the right ventricle and 1 patient underwent reoperation because of incomplete unroofing during the first operation. None of the patients with cardiopulmonary bypass technique had residual chest pain or other complications. Surgical unroofing of myocardial bridging with the aid of cardiopulmonary bypass is a safe and easy procedure with low operative risk and with excellent functional results.

Modal analysis of cable-stayed UHPC bridge

Directory of Open Access Journals (Sweden)

Tej Petr

2017-01-01

Full Text Available This paper deals with the dynamic analysis of cable-stayed UHPC bridge over the Vltava river near town Melnik in Czech Republic, Europe. Bridge serves for pedestrians and cyclists. This work aims to familiarize the reader with dynamic calculations carried out and the results obtained, describing the dynamic properties of proposed bridge. The construction of bridge is designed as a cable-stayed structure with prestressed bridge deck consisting of prefabricated UHPC panels and reversed “V” shaped steel pylon with height of approximately 40 meters. The deck is anchored using 24 steel hangers in one row in a steel pylon - 17 ropes in the main span and 7 cables on the other side. Range of the main span is 99.18 meters and the secondary span is 31.9 m. Deck width is 4.5 meters with 3.0 meters passing space. The bridge is designed for the possibility of passage of vehicles weighting up to 3.5 tonnes. Deck panels are made of UHPC with reinforcement. At the edge of the bridge on the side of the shorter span the bridge deck is firmly connected with abutment and on the other deck it is stored using a pair of sliding bearings.

Microwave Josephson generation in thin film superconducting bridges

International Nuclear Information System (INIS)

Gubankov, V.N.; Koshelets, V.P.; Ovsyannikov, G.A.

1975-01-01

Thin-film bridges have some advantage over other types of superconducting weak links: good definition of electromagnetic parameters and of weak region geometry. Up to now Josephson properties of bridges have been investigated by using indirect methods (the effect of magnetic field on the critical current I 0 , the bridge behavior in a microwave field, etc.). Direct experimental observation of Josephson radiation from autonomous thin film bridges is reported. Microwave radiation in tin bridges of 'variable' thickness has been investigated where the thickness of the film forming the bridge is far less than the thickness of the bank films. (Auth.)

Floating liquid bridge charge dynamics

Science.gov (United States)

Teschke, Omar; Soares, David Mendez; Gomes, Whyllerson Evaristo; Valente Filho, Juracyr Ferraz

2016-01-01

The interaction of liquid with electric fields is investigated in a configuration where up to 13 kV are applied between electrodes resulting in a 106 V/m electric field in the capillaries and where there is the formation of a free-standing fluid bridge in the interelectrode gap. The Mott-Gurney equation was fitted to the measured ionization current vs applied voltage curve which indicates that the ionization rate at the high-voltage anode electrode dimethylsulfoxide (DMSO) interface and space charging in the interelectrode gap determine the floating liquid bridge current for a given cathode-to-anode voltage. Space charge effects were measured in the cathode becker and also at the liquid bridge since the ionized charges at the anode migrate to the bridge outer surface and decrease the interfacial tension from 43 mJ/m2 to 29 mJ/m2. Two distinct structural regions then form the bridge, a charged plastic (bulk modulus ˜100 MPa) conducting outer layer with a surface conductivity of ˜10-9 Ω-1, which shapes and supports the floating fluid structure, and an inner liquid cylinder, where DMSO molecules flow.

Structure, function and carcinogenicity of metabolites of methylated and non-methylated polycyclic aromatic hydrocarbons: a comprehensive review.

Science.gov (United States)

Flesher, James W; Lehner, Andreas F

2016-01-01

The Unified Theory of PAH Carcinogenicity accommodates the activities of methylated and non-methylated polycyclic aromatic hydrocarbons (PAHs) and states that substitution of methyl groups on meso-methyl substituted PAHs with hydroxy, acetoxy, chloride, bromide or sulfuric acid ester groups imparts potent cancer producing properties. It incorporates specific predictions from past researchers on the mechanism of carcinogenesis by methyl-substituted hydrocarbons, including (1) requirement for metabolism to an ArCH2X type structure where X is a good leaving group and (2) biological substitution of a meso-methyl group at the most reactive center in non-methylated hydrocarbons. The Theory incorporates strong inferences of Fieser: (1) The mechanism of carcinogenesis involves a specific metabolic substitution of a hydrocarbon at its most reactive center and (2) Metabolic elimination of a carcinogen is a detoxifying process competitive with that of carcinogenesis and occurring by a different mechanism. According to this outlook, chemical or biochemical substitution of a methyl group at the reactive meso-position of non-methylated hydrocarbons is the first step in the mechanism of carcinogenesis for most, if not all, PAHs and the most potent metabolites of PAHs are to be found among the meso methyl-substituted hydrocarbons. Some PAHs and their known or potential metabolites and closely related compounds have been tested in rats for production of sarcomas at the site of subcutaneous injection and the results strongly support the specific predictions of the Unified Theory.

Methylated genes as new cancer biomarkers.

LENUS (Irish Health Repository)

Duffy, M J

2012-02-01

Aberrant hypermethylation of promoter regions in specific genes is a key event in the formation and progression of cancer. In at least some situations, these aberrant alterations occur early in the formation of malignancy and appear to be tumour specific. Multiple reports have suggested that measurement of the methylation status of the promoter regions of specific genes can aid early detection of cancer, determine prognosis and predict therapy responses. Promising DNA methylation biomarkers include the use of methylated GSTP1 for aiding the early diagnosis of prostate cancer, methylated PITX2 for predicting outcome in lymph node-negative breast cancer patients and methylated MGMT in predicting benefit from alkylating agents in patients with glioblastomas. However, prior to clinical utilisation, these findings require validation in prospective clinical studies. Furthermore, assays for measuring gene methylation need to be standardised, simplified and evaluated in external quality assurance programmes. It is concluded that methylated genes have the potential to provide a new generation of cancer biomarkers.

Are clinicopathological features of colorectal cancers with methylation in half of CpG island methylator phenotype panel markers different from those of CpG island methylator phenotype-high colorectal cancers?

Science.gov (United States)

Bae, Jeong Mo; Rhee, Ye-Young; Kim, Kyung Ju; Wen, Xianyu; Song, Young Seok; Cho, Nam-Yun; Kim, Jung Ho; Kang, Gyeong Hoon

2016-01-01

CpG island methylator phenotype (CIMP)-high (CIMP-H) colorectal cancer (CRC) is defined when a tumor shows methylation at greater than or equal to 60% of CIMP panel markers. Although CRCs with methylation at 50% of panel markers are classified as CIMP-low/CIMP-0 tumors, little is known regarding the clinicopathological and molecular features of CRCs with methylation at 4/8 panel markers (4/8 methylated markers) and whether they are akin to CIMP-H or CIMP-low/CIMP-0 CRCs in terms of their clinicopathological or molecular features. A total of 1164 cases of surgically resected CRC were analyzed for their methylation status in 8 CIMP panel markers, and the frequencies of various clinicopathological and molecular features were compared between CRCs with 0/8, 1/8 to 3/8, 4/8, and 5/8 to 8/8 methylated markers. CRCs with 4/8 methylated markers were closer to CRCs with 5/8 to 8/8 methylated markers in terms of sex distribution, mucin production, serration, nodal metastasis, CK7 expression, CK20 loss, and CDX2 loss frequencies and overall survival rate. CRCs with methylation at 4/8 markers were closer to CRCs with 1/8 to 3/8 methylated markers in terms of less frequent right colon location and poor differentiation. CRCs with 4/8 methylated markers showed the shortest overall survival time compared with CRCs with 0/8, 1/8 to 3/8, 4/8, or 5/8 to 8/8 methylated markers. In terms of clinicopathological and molecular features, CRCs with 4/8 methylated markers appeared to be closer to CIMP-H than to CIMP-low/CIMP-0 and would thus be better classified as CIMP-H if the CRCs require classification into either CIMP-H or CIMP-low/CIMP-0. Copyright © 2015 Elsevier Inc. All rights reserved.

Field performance of timber bridges. 11, Spearfish Creek stress-laminated box-beam bridge

Science.gov (United States)

J. P. Wacker; M. A. Ritter; K. Stanfill-McMillan

The Spearfish Creek bridge was constructed in 1992 in Spearfish, South Dakota. It is a single-span, stress-laminated, box-beam superstructure. Performance of the bridge is being monitored for 5 years, beginning at installation. This report summarizes results for the first 3-1/2 years of monitoring and includes information on the design, construction, and field...

Estimating bridge stiffness using a forced-vibration technique for timber bridge health monitoring

Science.gov (United States)

James P. Wacker; Xiping Wang; Brian Brashaw; Robert J. Ross

2006-01-01

This paper describes an effort to refine a global dynamic testing technique for evaluating the overall stiffness of timber bridge superstructures. A forced vibration method was used to measure the frequency response of several simple-span, sawn timber beam (with plank deck) bridges located in St. Louis County, Minnesota. Static load deflections were also measured to...

Design aids of NU I-girders bridges.

Science.gov (United States)

2010-05-01

Precast prestressed concrete I-Girder bridges have become the most dominant bridge system in the United States. In the early design : stages, preliminary design becomes a vital first step in designing an economical bridge. Within the state of Nebrask...

Faster bridge construction using precast substructures : brief.

Science.gov (United States)

2011-07-01

Bridge replacement often requires road closures and detours that frustrate road users. It remains a key goal of Wisconsin DOT to reduce construction-related road use interruptions. This will be a challenge with bridges: Bridge inspections in 2007 ide...

BUILDING "BRIDGES" WITH QUALITY ASSURANCE

Science.gov (United States)

The papr describes how, rather than building "bridges" across centuries, quality assurance (QA) personnel have the opportunity to build bridges across technical disciplines, between public and private organizations, and between different QA groups. As reviewers and auditors of a...

Inspection Based Evaluation of a Danish Road Bridge

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

In this paper it is shown how an inspection-based evaluation of a Danish road bridge may be performed using the BRIDGE1 and BRIDGE2 bridge management systems produced within the EC-supported research programme "Assessment of Performance and Optimal Strategies for Inspection and Maintenance...

Violin Bridge Mobility Analysis under In-Plane Excitation

Directory of Open Access Journals (Sweden)

Cheng-Zhong Zhang

2013-11-01

Full Text Available The vibration of a violin bridge is a dynamic contact vibration with two interfaces: strings-bridge, and bridge feet-top plate. In this paper, the mobility of an isolated bridge under in-plane excitation is explored using finite element modeling based on the contact vibration model. Numerical results show that the dynamic contact stiffness in the two contact interfaces has a great impact on the bridge mobility. A main resonance peak is observed in the frequency range of 2–3 kHz in the frequency response of the isolated bridge when the contact stiffness is smaller than a critical threshold. The main resonance peak frequency is affected by the contact stiffness as well. In order to verify the numerical findings, a novel experimental system is then designed on the basis of a piezoelectric dynamometer for bridge mobility analysis. Experimental results confirm the impact of the dynamic contact stiffness on the bridge mobility.

Violin bridge mobility analysis under in-plane excitation.

Science.gov (United States)

Zhang, Cheng-Zhong; Zhang, Guang-Ming; Ye, Bang-Yan; Liang, Li-Dong

2013-11-08

The vibration of a violin bridge is a dynamic contact vibration with two interfaces: strings-bridge, and bridge feet-top plate. In this paper, the mobility of an isolated bridge under in-plane excitation is explored using finite element modeling based on the contact vibration model. Numerical results show that the dynamic contact stiffness in the two contact interfaces has a great impact on the bridge mobility. A main resonance peak is observed in the frequency range of 2-3 kHz in the frequency response of the isolated bridge when the contact stiffness is smaller than a critical threshold. The main resonance peak frequency is affected by the contact stiffness as well. In order to verify the numerical findings, a novel experimental system is then designed on the basis of a piezoelectric dynamometer for bridge mobility analysis. Experimental results confirm the impact of the dynamic contact stiffness on the bridge mobility.

Monitoring bridge scour using fiber optic sensors.

Science.gov (United States)

2015-04-01

The scouring process excavates and carries away materials from the bed and banks of streams, and from : around the piers and abutments of bridges. Scour undermines bridges and may cause bridge failures due to : structural instability. In the last 30 ...

Covered Bridge Security Manual

Science.gov (United States)

Brett Phares; Terry Wipf; Ryan Sievers; Travis Hosteng

2013-01-01

The design, construction, and use of covered timber bridges is all but a lost art in these days of pre-stressed concrete, high-performance steel, and the significant growth both in the volume and size of vehicles. Furthermore, many of the existing covered timber bridges are preserved only because of their status on the National Registry of Historic Places or the...

Public response to bridge colors.

Science.gov (United States)

1973-01-01

To determine people's reactions to bridges painted in colors as white, yellow, green, blue, red, brown, black, and aluminum, two test bridges were selected in Charlottesville, Virginia. One was painted a different color each month and the other was k...

Dynamic behaviour of prestressed concrete bridges

International Nuclear Information System (INIS)

Javor, T.

1982-01-01

The paper presents the results of experimental research of dynamic effects on prestressed concrete bridges in dynamic load tests using testing vehicles. The bridges were passed over in both directions at various speeds also running over an artificial unevenness to produce impact loads. From investigated bridges are shown the dynamic quantities such as dynamic coefficients, natural frequency, logarithmical decrement of damping, etc. (orig.) [de

How does methylation suppress the electron-induced decomposition of 1-methyl-nitroimidazoles?

Science.gov (United States)

Kossoski, F.; Varella, M. T. do N.

2017-10-01

The efficient decomposition of nitroimidazoles (NIs) by low energy electrons is believed to underlie their radiosensitizing properties. Recent dissociative electron attachment (DEA) measurements showed that methylation at the N1 site unexpectedly suppresses the electron-induced reactions in 4(5)-NI. We report theoretical results that provide a clear interpretation of that astounding finding. Around 1.5 eV, DEA reactions into several fragments are initiated by a π* resonance, not considered in previous studies. The autoionization lifetime of this anion state, which limits the predissociation dynamics, is considerably shorter in the methylated species, thereby suppressing the DEA signals. On the other hand, the lifetime of the π* resonance located around 3 eV is less affected by methylation, which explains why DEA is still observed at these energies. Our results demonstrate how even a simple methylation can significantly modify the probabilities for DEA reactions, which may be significant for NI-based cancer therapy.

Salt bridge as a gatekeeper against partial unfolding.

Science.gov (United States)

Hinzman, Mark W; Essex, Morgan E; Park, Chiwook

2016-05-01

Salt bridges are frequently observed in protein structures. Because the energetic contribution of salt bridges is strongly dependent on the environmental context, salt bridges are believed to contribute to the structural specificity rather than the stability. To test the role of salt bridges in enhancing structural specificity, we investigated the contribution of a salt bridge to the energetics of native-state partial unfolding in a cysteine-free version of Escherichia coli ribonuclease H (RNase H*). Thermolysin cleaves a protruding loop of RNase H(*) through transient partial unfolding under native conditions. Lys86 and Asp108 in RNase H(*) form a partially buried salt bridge that tethers the protruding loop. Investigation of the global stability of K86Q/D108N RNase H(*) showed that the salt bridge does not significantly contribute to the global stability. However, K86Q/D108N RNase H(*) is greatly more susceptible to proteolysis by thermolysin than wild-type RNase H(*) is. The free energy for partial unfolding determined by native-state proteolysis indicates that the salt bridge significantly increases the energy for partial unfolding by destabilizing the partially unfolded form. Double mutant cycles with single and double mutations of the salt bridge suggest that the partially unfolded form is destabilized due to a significant decrease in the interaction energy between Lys86 and Asp108 upon partial unfolding. This study demonstrates that, even in the case that a salt bridge does not contribute to the global stability, the salt bridge may function as a gatekeeper against partial unfolding that disturbs the optimal geometry of the salt bridge. © 2016 The Protein Society.

Dissociation dynamics of methylal

Energy Technology Data Exchange (ETDEWEB)

Beaud, P; Frey, H -M; Gerber, T; Mischler, B; Radi, P P; Tzannis, A -P [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

1999-08-01

The dissociation of methylal is investigated using mass spectrometry, combined with a pyrolytic radical source and femtosecond pump probe experiments. Based on preliminary results two reaction paths of methylal dissociation are proposed and discussed. (author) 4 fig., 3 refs.

DNA methylation changes detected by methylation-sensitive amplified polymorphism in two contrasting rice genotypes under salt stress.

Science.gov (United States)

Wang, Wensheng; Zhao, Xiuqin; Pan, Yajiao; Zhu, Linghua; Fu, Binying; Li, Zhikang

2011-09-20

DNA methylation, one of the most important epigenetic phenomena, plays a vital role in tuning gene expression during plant development as well as in response to environmental stimuli. In the present study, a methylation-sensitive amplified polymorphism (MSAP) analysis was performed to profile DNA methylation changes in two contrasting rice genotypes under salt stress. Consistent with visibly different phenotypes in response to salt stress, epigenetic markers classified as stable inter-cultivar DNA methylation differences were determined between salt-tolerant FL478 and salt-sensitive IR29. In addition, most tissue-specific DNA methylation loci were conserved, while many of the growth stage-dependent DNA methylation loci were dynamic between the two genotypes. Strikingly, salt stress induced a decrease in DNA methylation specifically in roots at the seedling stage that was more profound in IR29 than in the FL478. This result may indicate that demethylation of genes is an active epigenetic response to salt stress in roots at the seedling stage, and helps to further elucidate the implications of DNA methylation in crop growth and development. Copyright © 2011. Published by Elsevier Ltd.

Synthesis of Nanometer-Sized Poly (methyl methacrylate) Polymer Network by Gold Nanoparticle Template

Science.gov (United States)

Liu, Fu-Ken; Hsieh, Shang-Yu; Ko, Fu-Hsiang; Chu, Tieh-Chi; Dai, Bau-Tong

2003-06-01

Gold nanoparticle/polymer composites have been produced using a one-system polymer synthesis. The linear polymer, poly (methyl methacrylate) (PMMA, MW = 15,000 g/mol) is applied for the stabilization of gold nanoparticles. The Fourier transfer infrared (FT-IR) analysis data and transition electron microscopy (TEM) image reveal that the core shell structure of gold/PMMA nanocomposite has been synthesized. The ratio of the concentration of the capping polymer material to the concentration of the gold precursor could control the sizes of gold nanoparticles. With specific concentration of the reductant, the core-shell nanostructure could be fluctuated in order. After heating treatment, the network structure of PMMA capped gold nanoparticles could be synthesized as confirmed by the TEM image. The result indicates that PMMA not only acts as the stabilizer, but also as the bridge of the neighboring gold nanoparticles.

IceBridge: Bringing a Field Campaign Home

Science.gov (United States)

Woods, J.; Beck, J.; Bartholow, S.

2015-12-01

IceBridge, a six-year NASA mission, is the largest airborne survey of Earth's polar ice ever flown. It will yield an unprecedented three-dimensional view of Arctic and Antarctic ice sheets, ice shelves and sea ice. These flights will provide a yearly, multi-instrument look at the behavior of the rapidly changing features of the Greenland and Antarctic ice. Data collected during IceBridge will help scientists bridge the gap in polar observations between NASA's Ice, Cloud and Land Elevation Satellite (ICESat) -- in orbit since 2003 -- and ICESat-2, planned for 2017. ICESat stopped collecting science data in 2009, making IceBridge critical for ensuring a continuous series of observations. IceBridge will use airborne instruments to map Arctic and Antarctic areas once a year at a minimum, with new campaigns being developed during the Arctic melt season. IceBridge flights are conducted in the spring and summer for the Arctic and in the fall over Antarctica. Other smaller airborne surveys around the world are also part of the IceBridge campaign. IceBridge actively engages the public and educators through a variety of outlets ranging from communications strategies through social media outlets, to larger organized efforts such as PolarTREC. In field activities include blog posts, photo updates, in flight chat sessions, and more intensive live events to include google hangouts, where field team members can interact with the public during a scheduled broadcast. The IceBridge team provides scientists and other team members with the training and support to become communicators in their own right. There is an exciting new initiative where IceBridge will be collaborating with Undergraduate and Graduate students to integrate the next generation of scientists and communicators into the Science Teams. This will be explored through partnerships with institutions that are interested in mentoring through project based initiatives.

MTHFR methylation moderates the impact of smoking on DNA methylation at AHRR for African American young adults.

Science.gov (United States)

Beach, Steven R H; Lei, Man Kit; Ong, Mei Ling; Brody, Gene H; Dogan, Meeshanthini V; Philibert, Robert A

2017-09-01

Smoking has been shown to have a large, reliable, and rapid effect on demethylation of AHRR, particularly at cg05575921, suggesting that methylation may be used as an index of cigarette consumption. Because the availability of methyl donors may also influence the degree of demethylation in response to smoking, factors that affect the activity of methylene tetrahydrofolate reductase (MTHFR), a key regulator of methyl group availability, may be of interest. In the current investigation, we examined the extent to which individual differences in methylation of MTHFR moderated the association between smoking and demethylation at cg05575921 as well as at other loci on AHRR associated with a main effect of smoking. Using a discovery sample (AIM, N = 293), and a confirmatory sample (SHAPE, N = 368) of young adult African Americans, degree of methylation of loci in the first exon of MTHFR was associated with amplification of the association between smoking and AHRR demethylation at cg05575921. However, genetic variation at a commonly studied MTHFR variant, C677T, did not influence cg05575921 methylation. The significant interaction between MTHFR methylation and the smoking-induced response at cg05575921 suggests a role for individual differences in methyl cycle regulation in understanding the effects of cigarette consumption on genome wide DNA methylation. © 2017 Wiley Periodicals, Inc.

Bridge Deterioration Prediction Model Based On Hybrid Markov-System Dynamic

Directory of Open Access Journals (Sweden)

Widodo Soetjipto Jojok

2017-01-01

Full Text Available Instantaneous bridge failure tends to increase in Indonesia. To mitigate this condition, Indonesia’s Bridge Management System (I-BMS has been applied to continuously monitor the condition of bridges. However, I-BMS only implements visual inspection for maintenance priority of the bridge structure component instead of bridge structure system. This paper proposes a new bridge failure prediction model based on hybrid Markov-System Dynamic (MSD. System dynamic is used to represent the correlation among bridge structure components while Markov chain is used to calculate temporal probability of the bridge failure. Around 235 data of bridges in Indonesia were collected from Directorate of Bridge the Ministry of Public Works and Housing for calculating transition probability of the model. To validate the model, a medium span concrete bridge was used as a case study. The result shows that the proposed model can accurately predict the bridge condition. Besides predicting the probability of the bridge failure, this model can also be used as an early warning system for bridge monitoring activity.

Synthesis of [methyl-{sup 14}C]crotonobetaine from DL-[methyl-{sup 14}C]carnitine

Energy Technology Data Exchange (ETDEWEB)

Loester, H.; Seim, H. [Leipzig Univ. (Germany). Inst. of Clinical Chemistry and Pathobiochemistry

1996-02-01

The causes of carnitine deficiency syndromes are not completely understood, but decomposition of L-carnitine in vivo is likely to be involved. Carnitine is metabolized to {gamma}-butyrobetaine, and crotonobetaine is probably an intermediate in this pathway. To validate experimentally the precursor-product relationship between the three physiologically occuring {gamma}-betaines - L-carnitine, crotonobetaine, {gamma}-butyrobetaine - labelling with stable or radioactive isotopes became necessary. Methyl-labelled carnitine isomers (L(-)-, D(+)- or DL-) or {gamma}-butyrobetaine can be easily synthesized by methylation of 4-amino-3-hydroxybutyric acid isomers or 4-aminobutyric acid, respectively. Because of problems with the 4-aminocrotonic acid, we synthesized labelled crotonbetaine from labelled carnitine. Thus, DL-[methyl-{sup 14}C]carnitine was dehydrated by reaction with concentrated sulfuric acid. After removal of the latter the products were separated and purified by ion exchange chromatography on DOWEX 50 WX8 (200 - 400 mesh) and gradient elution with hydrochloric acid. In addition to the labelled main product [methyl-{sup 14}C]crotonobetaine (yield about 50 %), [methyl-{sup 14}C]glycine betaine and [methyl-{sup 14}C]acetonyl-trimethylammonium (ATMA) were formed. The end products were identified by combined thin layer chromatography/autoradiography and quantified by liquid scintillation counting. (Author).

Quantum Bidding in Bridge

Science.gov (United States)

Muhammad, Sadiq; Tavakoli, Armin; Kurant, Maciej; Pawłowski, Marcin; Żukowski, Marek; Bourennane, Mohamed

2014-04-01

Quantum methods allow us to reduce communication complexity of some computational tasks, with several separated partners, beyond classical constraints. Nevertheless, experimental demonstrations of this have thus far been limited to some abstract problems, far away from real-life tasks. We show here, and demonstrate experimentally, that the power of reduction of communication complexity can be harnessed to gain an advantage in a famous, immensely popular, card game—bridge. The essence of a winning strategy in bridge is efficient communication between the partners. The rules of the game allow only a specific form of communication, of very low complexity (effectively, one has strong limitations on the number of exchanged bits). Surprisingly, our quantum technique does not violate the existing rules of the game (as there is no increase in information flow). We show that our quantum bridge auction corresponds to a biased nonlocal Clauser-Horne-Shimony-Holt game, which is equivalent to a 2→1 quantum random access code. Thus, our experiment is also a realization of such protocols. However, this correspondence is not complete, which enables the bridge players to have efficient strategies regardless of the quality of their detectors.

Re-Assessment of Concrete Bridges

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

In this paper two aspects of re-assessment of the reliability of concrete bridges are discussed namely modelling of the corrosion of reinforcement and updating of uncertain variables. The main reason for deterioration of concrete bridges is corrosion of the reinforcement. Therefore, modelling...

Rapid replacement/construction of bridges.

Science.gov (United States)

2012-11-01

Bridges are a key element of the transportation system because they control system capacity and are normally built at : the highest cost to the system. Once a bridge reaches its useful design service life, it needs to be replaced or : reconstructed i...

33 CFR 118.80 - Lights on bascule bridges.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on bascule bridges. 118.80 Section 118.80 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.80 Lights on bascule bridges. (a) Lift span lights. Each lift span of...

Precast Pearl-Chain concrete arch bridges

DEFF Research Database (Denmark)

Halding, Philip Skov; Hertz, Kristian Dahl; Schmidt, Jacob Wittrup

2015-01-01

A Pearl-Chain Bridge is a closed-spandrel arch bridge consisting of a number of straight pre-fabricated so called Super-Light Deck elements put together in an arch shape by post-tensioning cables. Several Pearl-Chain arches can be positioned adjacent to each other by a crane to achieve a bridge...... of a desired width. On top of the arch is a filling material to level out the surface of the above road. The filling only transfers vertical loads to the arch. The geometry and material properties of Super-Light Decks are presented, and we refer to several fullscale tests of Pearl-Chain arches where...... the technology was used. We also study other important components and details in the Pearl-Chain Bridge concept and review the effects of different types of loads. A theoretical case study of a circular 30 m span Pearl-Chain Bridge is presented showing the influence of a number of parameters: The number of post...

The association between personal sun exposure, serum vitamin D and global methylation in human lymphocytes in a population of healthy adults in South Australia

Energy Technology Data Exchange (ETDEWEB)

Nair-Shalliker, Visalini, E-mail: visalinin@nswcc.org.au [Cancer Research Division, Cancer Council New South Wales (Australia); Dhillon, Varinderpal [CSIRO Food and Nutritional Sciences (Australia); Clements, Mark [Department of Medical Epidemiology and Biostatistics, Karolinska Institutet (Sweden); Armstrong, Bruce K. [Sydney School of Public Health, University of Sydney (Australia); Fenech, Michael [CSIRO Food and Nutritional Sciences (Australia)

2014-07-15

Highlights: • Solar UV exposure is positively correlated with LINE 1 hypomethylation. • This was observed in human peripheral blood lymphocytes. • There was no evident effect modification by serum vitamin D (25OHD) levels. • This was observed in a population of healthy adults from South Australia. - Abstract: Background: There is a positive association between solar UV exposure and micronucleus frequency in peripheral blood lymphocytes (PBL) and this association may be stronger when serum vitamin D (25(OH)D) levels are insufficient (<50 nmol/L). Micronucleus formation can result from global hypomethylation of DNA repeat sequences. The aim of this analysis was to evaluate the relationship between solar UV exposure and methylation pattern in LINE-1 repetitive elements in PBL DNA and to see if serum 25(OH)D levels modify it. Method: Personal solar UV exposure was estimated from hours of outdoor exposure over 6 weeks recalled at the time of blood collection in 208 male and female participants living in South Australia. Methylation in LINE-1 repetitive elements was assessed in PBL using pyrosequencing. Results: Methylation in LINE-1 decreased with increasing solar UV exposure (% decrease = 0.5% per doubling of sUV; 95%CI: −0.7 to −0.2 p{sub value} = 0.00003). Although there was no correlation between LINE-1 methylation and micronucleus frequency, there was a 4.3% increase (95%CI: 0.6–8.1 p-value = 0.02) in nucleoplasmic bridges and a 4.3% increase in necrosis (CI: 1.9–6.8 p-value = 0.0005) for every 1% increase in LINE-1 methylation. Serum 25(OH)D was not associated with DNA methylation; or did it modify the association of solar UV with DNA methylation. Conclusion: Exposure to solar UV radiation may reduce DNA methylation in circulating lymphocytes. This association does not appear to be influenced or mediated by vitamin D status.

Determination of in-situ strength on selected bridge element concrete girder and slab of Nagtahan bridge using rebound hammer test

International Nuclear Information System (INIS)

Uy, Bernadette Betsy B.; Banaga, Renato T.

2013-01-01

This study examined the extent of the damage due to fire on the affected areas of the bridge structure. The need to assess the damage of the Nagtahan Bridge is very useful to provide appropriate measures in the repair or in the reinforcement of the bridge, hence will ensure its strength and integrity. The study included two (2) spans of the bridge deck/slab with specific locations of the bridge that were subjected for testing. The Rebound Hammer was used as a preliminary test in evaluating the bridge condition. Its capability is to assess the in-place uniformity of concrete, to delineate regions in a structure of poor quality or deteriorated concrete, and to estimate the in-place strength; and ultimately, for relative comparison between the different structures of the bridge. With the use of the NDT Rebound Hammer Test, the researchers were able to determine whether or not the in-situ strength of the bridge's concrete has been weakened due to fire. The DPW-Standard Specification is the government acceptable manual, containing the acceptance criteria, used as the basis for standard construction procedures in the department.(author)

Process for the production of methyl methacrylate

NARCIS (Netherlands)

Eastham, G.R.; Johnson, D.W.; Straathof, A.J.J.; Fraaije, Marco; Winter, Remko

2015-01-01

A process of producing methyl methacrylate or derivatives thereof is described. The process includes the steps of; (i) converting 2-butanone to methyl propionate using a Baeyer-Villiger monooxygenase, and (ii) treating the methyl propionate produced to obtain methyl methacrylate or derivatives

Methylation patterns in marginal zone lymphoma.

Science.gov (United States)

Arribas, Alberto J; Bertoni, Francesco

Promoter DNA methylation is a major regulator of gene expression and transcription. The identification of methylation changes is important for understanding disease pathogenesis, for identifying prognostic markers and can drive novel therapeutic approaches. In this review we summarize the current knowledge regarding DNA methylation in MALT lymphoma, splenic marginal zone lymphoma, nodal marginal zone lymphoma. Despite important differences in the study design for different publications and the existence of a sole large and genome-wide methylation study for splenic marginal zone lymphoma, it is clear that DNA methylation plays an important role in marginal zone lymphomas, in which it contributes to the inactivation of tumor suppressors but also to the expression of genes sustaining tumor cell survival and proliferation. Existing preclinical data provide the rationale to target the methylation machinery in these disorders. Copyright © 2016 Elsevier Ltd. All rights reserved.

Future Trends in Reliability-Based Bridge Management

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

Future bridge management systems will be based on simple stochastic models predicting the residual strength of structural elements. The current deterministic management systems are not effective in optimizing e.g. the life cycle cost of a bridge or a system of bridges. A number of important factors...

Assessment of Replacement Bridge using Proof Load Test

Science.gov (United States)

Sundru, Saibabu

2017-11-01

This work begins with an overview of the condition assessment of old bridge and explained reasons for demolishing of the bridge. Briefly presented flexural analysis of two stage post-tensioned prestressed concrete girder, which will be replace the old (new bridge). Construction of I-girder and composite girder at first stage and second stage prestressing respectively is explained with figures. Assessment of the load-caring capacity of the one span of the replacement bridge with simple supports using proof load test is presented which is mandatory according to Indian standards. Weighted sand bags were used to load the bridge up to a predetermined service load with impact factor. Deflections of the I-girders of the bridge were measured at selected locations along and across the bridge span and compared with computed values. Linear response was observed during loading and unloading. Considering the load test results, theoretical estimation and criteria as stipulated in codes of practice, it can be inferred that prestressed concrete I-girder bridge span has adequate capacity to carry the loads and hence, deemed to have passed the test.

DNA methylation-based variation between human populations.

Science.gov (United States)

Kader, Farzeen; Ghai, Meenu

2017-02-01

Several studies have proved that DNA methylation affects regulation of gene expression and development. Epigenome-wide studies have reported variation in methylation patterns between populations, including Caucasians, non-Caucasians (Blacks), Hispanics, Arabs, and numerous populations of the African continent. Not only has DNA methylation differences shown to impact externally visible characteristics, but is also a potential biomarker for underlying racial health disparities between human populations. Ethnicity-related methylation differences set their mark during early embryonic development. Genetic variations, such as single-nucleotide polymorphisms and environmental factors, such as age, dietary folate, socioeconomic status, and smoking, impacts DNA methylation levels, which reciprocally impacts expression of phenotypes. Studies show that it is necessary to address these external influences when attempting to differentiate between populations since the relative impacts of these factors on the human methylome remain uncertain. The present review summarises several reported attempts to establish the contribution of differential DNA methylation to natural human variation, and shows that DNA methylation could represent new opportunities for risk stratification and prevention of several diseases amongst populations world-wide. Variation of methylation patterns between human populations is an exciting prospect which inspires further valuable research to apply the concept in routine medical and forensic casework. However, trans-generational inheritance needs to be quantified to decipher the proportion of variation contributed by DNA methylation. The future holds thorough evaluation of the epigenome to understand quantification, heritability, and the effect of DNA methylation on phenotypes. In addition, methylation profiling of the same ethnic groups across geographical locations will shed light on conserved methylation differences in populations.

Planning of Tatara Bridge. Chodai shachokyo-Tataraohashi-no keikaku gaiyo

Energy Technology Data Exchange (ETDEWEB)

Okukawa, A. (Honshu-Shikoku Bridge Authority, Tokyo (Japan))

1991-12-05

The outline of the Tatara Bridge is given to introduce the features of the entire structural system and fundamental problems concerning the construction of the huge cable stayed bridge. The central span of the bridge is 890m. The topography and geological features of the bridging point are reviewed, and social conditions such as being in a national park, safety for sailing, etc. are taken into consideration for various technological studies on the construction of the huge bridge. Bridge piers are provided in the side spans and appropriate counter weight is loaded to design a more economical bridge which is more suitable for the topography as compared with a suspension bridge. The cable stayed bridge requires no anchorage which is necessary for a suspension bridge with very little topological alteration, and an excellent result is obtained both in cost and term of construction as compared with a suspension bridge. The rigidity of the cable stayed bridge is high, and the stability of the resistance to wind of the structure is also very satisfactory. As a result, it is concluded that the bridge can be designed and constructed using currently available technologies, and a cable stayed bridge is selected in August, 1990 as the type for the Tatara Bridge. 9 figs., 1 tab.

33 CFR 118.85 - Lights on vertical lift bridges.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on vertical lift bridges... BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.85 Lights on vertical lift bridges. (a) Lift span lights. The vertical lift span of every vertical lift bridge shall be lighted so that the center of the...

Crystal structures of titanium–aluminium and –gallium complexes bearing two μ2-CH3 units

Directory of Open Access Journals (Sweden)

Tim Oswald

2017-05-01

Full Text Available The isotypic crystal structures of two titanocene complexes containing an EMe3 unit (E = Al, Ga; Me = methyl with two μ2-coordinating methyl groups, namely [μ-1(η5-(adamantan-1-yl-2κC1cycylopentadienyl]di-μ2-methyl-methyl-2κC-[1(η5-pentamethylcyclopentadienyl]aluminiumtitanium(III, [AlTi(CH33(C10H15(C15H18], and [μ-1(η5-(adamantan-1-yl-2κC1cycylopentadienyl]di-μ2-methyl-methyl-2κC-[1(η5-pentamethylcyclopentadienyl]galliumtitanium(III, [GaTi(CH33(C10H15(C15H18], are reported. Reacting a dinuclear nitrogen-bridged low-valent titanium(III complex with the Lewis acids AlMe3 or GaMe3 results in the loss of molecular dinitrogen and the formation of two monomeric titanocene(III fragments bearing two μ2-bridging methyl groups. Single crystal X-ray diffraction reveals the formation of a new E—C bond involving the pentafulvene ligand while the bridging and terminal methyl groups remain intact.

TMACS test procedure TP012: Panalarm software bridge

International Nuclear Information System (INIS)

Washburn, S.J.

1994-01-01

This Test Procedure addresses the testing of the functionality of the Tank Monitor and Control System (TMACS) Panalarm bridge software. The features to be tested are: Bridge Initialization Options; Bridge Communication; Bridge Performance; Testing Checksum Errors; and Testing Command Reject Errors. Only the first three could be tested; the last two have been deferred to a later date

Running Safety of Trains under Vessel-Bridge Collision

Directory of Open Access Journals (Sweden)

Yongle Li

2015-01-01

Full Text Available To optimize the sensor placement of the health monitoring system, the dynamic behavior of the train-bridge system subjected to vessel-collision should be studied in detail firstly. This study thus focuses on the characteristics of a train-bridge system under vessel-bridge collision. The process of the vessel-bridge collision is simulated numerically with a reliable finite element model (FEM. The dynamic responses of a single car and a train crossing a cable-stayed bridge are calculated. It is shown that the collision causes significant increase of the train’s lateral acceleration, lateral wheelset force, wheel unloading rate, and derailment coefficient. The effect of the collision on the train’s vertical acceleration is much smaller. In addition, parametric studies with various train’s positions, ship tonnage, and train speed are performed. If the train is closer to the vessel-bridge collision position or the ship tonnage is larger, the train will be more dangerous. There is a relatively high probability of running danger at a low speed, resulting from longer stay of the train on the bridge. The train’s position, the ship tonnage, and the train speed must be considered when determining the most adverse conditions for the trains running on bridges under vessel-bridge collision.

Synthesis of [Ru3(μ3-NPh)(Br)(CO)9]- on self-assembled monolayers of di(3-aminopropyl)viologen/ITO surfaces and its application to photoelectrochemical cells

International Nuclear Information System (INIS)

Lee, Deok Yeon; Lee, Mi-Sun; Lim, Iseul; Kang, Soon Hyung; Nah, Yoon-Chae; Lee, Wonjoo; Han, Sung-Hwan

2011-01-01

Triruthenium carbonyl clusters {[Ru 3 (Br)(CO) 11 ] - (denoted as Ru-1), [Ru 3 (μ 2 -Br)(CO) 10 ] - (denoted as Ru-2), and [Ru 3 (μ 3 -NPh)(Br)(CO) 9 ] - (denoted as Ru-3)} were synthesized on di(3-aminopropyl)viologen (DAPV)/indium tin oxide (ITO) using a surface reaction in a ruthenium (III) carbonyl [Ru 3 (CO) 12 ] solution, and were applied to photoelectrochemical cells (PECs) at the molecular level. The formation of DAPV on ITO was realized in the form of self-assembled monolayers. Ru 3 (CO) 12 then easily reacted with the Br - of DAPV, and a mixture of Ru-1 and Ru-2 was formed on DAPV/ITO. Furthermore, Ru-3 was successfully anchored on DAPV/ITO by adding nitrosobenzene in order to react with Ru-2 on DAPV/ITO. The photocurrents of (Ru-1 and Ru-2)/DAPV/ITO and Ru-3/DAPV/ITO in PECs at the molecular level were 6.3 nA cm -2 and 8.6 nA cm -2 , respectively. The quantum yield of Ru-3/DAPV/ITO was ∼0.8%. Time-resolved photoluminescence spectroscopy and emission spectroscopy were recorded to bring out the photoinduced charge transfer process from ruthenium clusters to DAPV.

Rapid analysis of heterogeneously methylated DNA using digital methylation-sensitive high resolution melting: application to the CDKN2B (p15) gene

DEFF Research Database (Denmark)

Candiloro, Ida Lm; Mikeska, Thomas; Hokland, Peter

2008-01-01

ABSTRACT: BACKGROUND: Methylation-sensitive high resolution melting (MS-HRM) methodology is able to recognise heterogeneously methylated sequences by their characteristic melting profiles. To further analyse heterogeneously methylated sequences, we adopted a digital approach to MS-HRM (dMS-HRM) t......ABSTRACT: BACKGROUND: Methylation-sensitive high resolution melting (MS-HRM) methodology is able to recognise heterogeneously methylated sequences by their characteristic melting profiles. To further analyse heterogeneously methylated sequences, we adopted a digital approach to MS-HRM (d......MS-HRM) that involves the amplification of single templates after limiting dilution to quantify and to determine the degree of methylation. We used this approach to study methylation of the CDKN2B (p15) cell cycle progression inhibitor gene which is inactivated by DNA methylation in haematological malignancies...... the methylated alleles and assess the degree of methylation. Direct sequencing of selected dMS-HRM products was used to determine the exact DNA methylation pattern and confirmed the degree of methylation estimated by dMS-HRM. CONCLUSION: dMS-HRM is a powerful technique for the analysis of methylation in CDKN2B...

Inductive effect of methyl group in a series of methylated indoles: A ...

Indian Academy of Sciences (India)

Vol. 125, No. 4, July 2013, pp. 905–912. c Indian Academy of Sciences. Inductive effect of methyl group in a series of methylated indoles: A graph theoretical analysis in the light of density functional theory and correlation with experimental charge transfer transition energies. AMIT S TIWARYa,∗ and ASOK K MUKHERJEEb.

Fatigue test on aluminium bridges

NARCIS (Netherlands)

Maljaars, J.; Soetens, F.; Straalen, van IJ.J.

2005-01-01

Traffic bridges are subjected to variable loads and should therefore be checked on fatigue. Especially low weight materials, like aluminium, are sensitive to fatigue, because the variable load is a substantial part of the total load. This paper shows the structural design of an aluminium bridge

Vulnerability of bridges to fire

DEFF Research Database (Denmark)

Giuliani, Luisa; Crosti, C.; Gentili, F.

2012-01-01

Even if recent effort in developing methodology and measures for design structures against fire and explosions has been mostly focused on buildings, bridges can also be very sensitive to those actions, as witnesses by some recent bridge accidents, which caused major economic losses and also endan...

Methylation-Specific PCR Unraveled

Directory of Open Access Journals (Sweden)

Sarah Derks

2004-01-01

Full Text Available Methylation‐specific PCR (MSP is a simple, quick and cost‐effective method to analyze the DNA methylation status of virtually any group of CpG sites within a CpG island. The technique comprises two parts: (1 sodium bisulfite conversion of unmethylated cytosine's to uracil under conditions whereby methylated cytosines remains unchanged and (2 detection of the bisulfite induced sequence differences by PCR using specific primer sets for both unmethylated and methylated DNA. This review discusses the critical parameters of MSP and presents an overview of the available MSP variants and the (clinical applications.

Bridge employment after early retirement: a bridge to better postretirement well-being of older adults?

NARCIS (Netherlands)

Dingemans, E.

2012-01-01

Using a retirement arrangement does not necessarily mean that people retire fulltime. The phenomenon of bridge employment, already studied in the US, becomes increasingly popular among older adults in the Netherlands. The question is to what extent bridge employment can be beneficial for well-being

Synthesis of 14C-labelled α-methyl tyrosine

International Nuclear Information System (INIS)

Rajagopal, S.; Venkatachalam, T.K.; Conway, T.; Diksic, M.

1992-01-01

A new route for the preparation of radioactively labelled α-methyl L-tyrosine is described. The labelling at the α position has been successfully achieved with 14 C-, 11 C- (very preliminary, unpublished), and 3 H-labelled methyl iodide. A detailed report on 14 C-labelling at the α position and the hydrolysis of 4-methoxy α-methyl phenylalanine is presented. The alkylation proceeds via the methylation of the carbanion of N-benzylidene 4-methoxy phenylalanine methyl ester 2. Hydrolysis of 4-O methyl tyrosine to tyrosine by HBr and HI were analysed and used in the optimization of the hydrolysis conditions of 4. Enantiomeric purity of the isolated L-isomer has been found to be 99% as judged by HPLC. Pseudo first-order rate constant for the hydrolysis of 14 C-labelled α-methyl 4-methoxy phenyl alanine methyl ester was determined. Preliminary findings of the 3 H- and 11 C-radiolabelled α-methyl tyrosine (methyl labelled) are also mentioned. For the first time it was shown that α-methyl D,L-tyrosine can be separated into enantiomerically pure α-methyl D- and L-tyrosine using a CHIRALPAK WH column. (author)

Liberation of methyl acrylate from metallalactone complexes via M-O ring opening (M = Ni, Pd) with methylation agents

KAUST Repository

Lee, S. Y Tina; Ghani, Amylia Abdul; D'Elia, Valerio; Cokoja, Mirza; Herrmann, Wolfgang A.; Basset, Jean-Marie; Kü hn, Fritz

2013-01-01

Ring opening of various nickela- and palladalactones induced by the cleavage of the M-O bond by methyl trifluoromethanesulfonate (MeOTf) and methyl iodide (MeI) is examined. Experimental evidence supports the mechanism of ring opening by the alkylating agent followed by β-H elimination leading to methyl acrylate and a metal-hydride species. MeOTf shows by far higher efficiency in the lactone ring opening than any other methylating agent including the previously reported methyl iodide. © 2013 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.

Rational Design of a Highly Potent and Selective Peptide Inhibitor of PACE4 by Salt Bridge Interaction with D160 at Position P3.

Science.gov (United States)

Dianati, Vahid; Shamloo, Azar; Kwiatkowska, Anna; Desjardins, Roxane; Soldera, Armand; Day, Robert; Dory, Yves L

2017-08-08

PACE4, a member of the proprotein convertases (PCs) family of serine proteases, is a validated target for prostate cancer. Our group has developed a potent and selective PACE4 inhibitor: Ac-LLLLRVKR-NH 2 . In seeking for modifications to increase the selectivity of this ligand toward PACE4, we replaced one of its P3 Val methyl groups with a basic group capable of forming a salt bridge with D160 of PACE4. The resulting inhibitor is eight times more potent than the P3 Val parent inhibitor and two times more selective over furin, because the equivalent salt bridge with furin E257 is not optimal. Moreover, the β-branched nature of the new P3 residue favors the extended β-sheet conformation usually associated with substrates of proteases. This work provides new insight for better understanding of β-sheet backbone-backbone interactions between serine proteases and their peptidic ligands. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Methylation pathways in schizophrenia

International Nuclear Information System (INIS)

Sargent, T.W. III.

1982-01-01

Research on the biochemical causes of human psychosis concentrates on investigating whether schizophremia is linked to abnormalities in the metabolism of methyl carbon groups in the body. The metabolism of C-14 labeled methyl groups in methionine is studied in animals, normal subjects and patient volunteers

Simultaneous Determination of Salicylic Acid, Jasmonic Acid, Methyl Salicylate, and Methyl Jasmonate from Ulmus pumila Leaves by GC-MS

Directory of Open Access Journals (Sweden)

Zhi-hong Huang

2015-01-01

Full Text Available Salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate are important phytohormones and defensive signaling compounds, so it is of great importance to determine their levels rapidly and accurately. The study uses Ulmus pumila leaves infected by Tetraneura akinire Sasaki at different stages as materials; after extraction with 80% methanol and ethyl acetate and purification with primary secondary amine (PSA and graphitized carbon blacks (GCB, the contents of signal compounds salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate were determined by GC-MS. The results showed that the level of salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate increased remarkably in U. pumila once infected by T. akinire Sasaki, but the maximums of these four compounds occurred at different times. Salicylic acid level reached the highest at the early stage, and jasmonic acid level went to the maximum in the middle stage; by contrast, change of content of methyl salicylate and methyl jasmonate was the quite opposite.

Simultaneous Determination of Salicylic Acid, Jasmonic Acid, Methyl Salicylate, and Methyl Jasmonate from Ulmus pumila Leaves by GC-MS.

Science.gov (United States)

Huang, Zhi-Hong; Wang, Zhi-Li; Shi, Bao-Lin; Wei, Dong; Chen, Jian-Xin; Wang, Su-Li; Gao, Bao-Jia

2015-01-01

Salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate are important phytohormones and defensive signaling compounds, so it is of great importance to determine their levels rapidly and accurately. The study uses Ulmus pumila leaves infected by Tetraneura akinire Sasaki at different stages as materials; after extraction with 80% methanol and ethyl acetate and purification with primary secondary amine (PSA) and graphitized carbon blacks (GCB), the contents of signal compounds salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate were determined by GC-MS. The results showed that the level of salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate increased remarkably in U. pumila once infected by T. akinire Sasaki, but the maximums of these four compounds occurred at different times. Salicylic acid level reached the highest at the early stage, and jasmonic acid level went to the maximum in the middle stage; by contrast, change of content of methyl salicylate and methyl jasmonate was the quite opposite.

Synthesis of DL-adrenaline (methyl C{sup 14}) (1961); Synthese de la DL-adrenaline (methyle {sup 14}C) (1961)

Energy Technology Data Exchange (ETDEWEB)

Pichat, L; Audinot, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1961-07-01

The sodium derivative of 5-3-4 dibenzyl oxyphenyl 2-oxazolidinone reacted with methyl iodide {sup 14}C, in stoichiometric quantity, gives rise to the corresponding N-methyl {sup 14}C derivative. The oxazolidinone ring is opened by concentrated hydrochloric acid and the benzyl groups removed by catalytic hydrogenolysis. Adrenaline methyl {sup 14}C is then purified on Dowex 50 X-12 exchange resin. Overall-yield is 45 per cent based upon methyl iodide {sup 14}C. (author) [French] Le derive sode de la (dibenzyloxy-3-4-phenyl)-5 oxazolidinone-2 traite par l'iodure de methyle {sup 14}C, en proportion stoechiometrique, fournit le derive N-methyle {sup 14}C correspondant. Apres ouverture du cycle oxazolidinone par HCL concentre et debenzylation par hydrogenation catalytique, on purifie l'adrenaline (methyle {sup 14}C) par chromatographie sur resine echangeuse Dowex 50 X-12. Le rendement est de 45 pour cent par rapport a l'iodure de methyle {sup 14}C. (auteurs)

Synthesis of DL-adrenaline (methyl C{sup 14}) (1961); Synthese de la DL-adrenaline (methyle {sup 14}C) (1961)

Energy Technology Data Exchange (ETDEWEB)

Pichat, L.; Audinot, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1961-07-01

The sodium derivative of 5-3-4 dibenzyl oxyphenyl 2-oxazolidinone reacted with methyl iodide {sup 14}C, in stoichiometric quantity, gives rise to the corresponding N-methyl {sup 14}C derivative. The oxazolidinone ring is opened by concentrated hydrochloric acid and the benzyl groups removed by catalytic hydrogenolysis. Adrenaline methyl {sup 14}C is then purified on Dowex 50 X-12 exchange resin. Overall-yield is 45 per cent based upon methyl iodide {sup 14}C. (author) [French] Le derive sode de la (dibenzyloxy-3-4-phenyl)-5 oxazolidinone-2 traite par l'iodure de methyle {sup 14}C, en proportion stoechiometrique, fournit le derive N-methyle {sup 14}C correspondant. Apres ouverture du cycle oxazolidinone par HCL concentre et debenzylation par hydrogenation catalytique, on purifie l'adrenaline (methyle {sup 14}C) par chromatographie sur resine echangeuse Dowex 50 X-12. Le rendement est de 45 pour cent par rapport a l'iodure de methyle {sup 14}C. (auteurs)

A Simple and Universal Resistive-Bridge Sensors Interface

Directory of Open Access Journals (Sweden)

Sergey Y. YURISH

2011-02-01

Full Text Available Resistive-bridge sensors are widely used in various sensor systems. There are many sensor signal conditioners from different manufacturers for such sensing elements. However, no one existing on the modern market integrated converter for resistive bridge sensors can work with both: resistive-bridge sensing elements and resistive-to-frequency and -duty-cycle converters’ outputs. A proposed and described in the article universal interface for resistive-bridge sensing elements and bridge-output-to-frequency and/or duty cycle converters based on the designed Universal Sensors and Transducers Interface (USTI integrated. It is based on a simple, cost effective three-point measuring technique and does not require any additional active components. The USTI IC is realized in a standard CMOS technology. The active supply current at operating voltage +4.5 V and clock frequency 20 MHz is not more than 9.5 mA This paper reports experimental results with a strain gauges bridge emulator and differential pressure resistive bridge sensor SX30GD2.

Prestressed concrete cable-stayed bridge; PC shachokyo `Tajiri sky bridge` no seko

Energy Technology Data Exchange (ETDEWEB)

Kaida, Y.; Tsujino, F. [Osaka Prefectural Government Office, Osaka (Japan); Yamamoto, T.; Hishiki, Y.; Saito, K.

1995-01-30

The outline on the execution of PC cable-stayed bridge `Tajiri Sky Bridge` which was built at the opposite coast of Kansai International Airport was reported. This bridge is a double-sided suspension PC cable-stayed bridge with a tower height of 93.6 m having a main beam which is 26.3 m wide, featuring H-type main tower with one side beam, a smooth main beam structure, the leg top part with a large section, etc. A large-capacity factory manufacturing type non-grout cable with a pull strength of 1,900 ton class was adopted for the diagonal bracing. The leg top part is in a massive concrete structure so that, for avoiding the crack of cement due to temperature, a low heat build-up furnace cement was adopted, the water reducing agent was used, pre-cooling and side-clamping PC steel material were adopted and moderate pre-stress was introduced. In the execution of the connection part of the main beam, for preventing the deflection fluctuation due to the change of the main beam/main tower/diagonal bracing due to temperature and vibration due to wind, the earth anchor was used to tentatively fix the extended part. During execution, the wind velocity was strong reaching 25 m/s, which did not produce any problems. 1 ref., 24 figs., 3 tabs.

BRIDGES for Young Adolescents in North Dakota.

Science.gov (United States)

Harris, Mary McDonnell

The BRIDGES Project was initiated to explore ways for North Dakota to provide young people with stronger bridges from childhood to adulthood. This report summarizes recommendations of the 1990-91 Governor's Task Force on Early Adolescence. The recommendations concern practical actions for the building of bridges by the following groups: (1)…

Lifetime Reliability Assessment of Concrete Slab Bridges

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

A procedure for lifetime assesment of the reliability of short concrete slab bridges is presented in the paper. Corrosion of the reinforcement is the deterioration mechanism used for estimating the reliability profiles for such bridges. The importance of using sensitivity measures is stressed....... Finally the produce is illustrated on 6 existing UK bridges....

33 CFR 165.1187 - Security Zones; Golden Gate Bridge and the San Francisco-Oakland Bay Bridge, San Francisco Bay...

Science.gov (United States)

2010-07-01

... Limited Access Areas Eleventh Coast Guard District § 165.1187 Security Zones; Golden Gate Bridge and the... Golden Gate Bridge and the San Francisco-Oakland Bay Bridge, in San Francisco Bay, California. (b... siren, radio, flashing light, or other means, the operator of a vessel shall proceed as directed. [COTP...

Transgenerational epigenetics: Inheritance of global cytosine methylation and methylation-related epigenetic markers in the shrub Lavandula latifolia.

Science.gov (United States)

Herrera, Carlos M; Alonso, Conchita; Medrano, Mónica; Pérez, Ricardo; Bazaga, Pilar

2018-04-01

The ecological and evolutionary significance of natural epigenetic variation (i.e., not based on DNA sequence variants) variation will depend critically on whether epigenetic states are transmitted from parents to offspring, but little is known on epigenetic inheritance in nonmodel plants. We present a quantitative analysis of transgenerational transmission of global DNA cytosine methylation (= proportion of all genomic cytosines that are methylated) and individual epigenetic markers (= methylation status of anonymous MSAP markers) in the shrub Lavandula latifolia. Methods based on parent-offspring correlations and parental variance component estimation were applied to epigenetic features of field-growing plants ('maternal parents') and greenhouse-grown progenies. Transmission of genetic markers (AFLP) was also assessed for reference. Maternal parents differed significantly in global DNA cytosine methylation (range = 21.7-36.7%). Greenhouse-grown maternal families differed significantly in global methylation, and their differences were significantly related to maternal origin. Methylation-sensitive amplified polymorphism (MSAP) markers exhibited significant transgenerational transmission, as denoted by significant maternal variance component of marker scores in greenhouse families and significant mother-offspring correlations of marker scores. Although transmission-related measurements for global methylation and MSAP markers were quantitatively lower than those for AFLP markers taken as reference, this study has revealed extensive transgenerational transmission of genome-wide global cytosine methylation and anonymous epigenetic markers in L. latifolia. Similarity of results for global cytosine methylation and epigenetic markers lends robustness to this conclusion, and stresses the value of considering both types of information in epigenetic studies of nonmodel plants. © 2018 Botanical Society of America.

Analysis of DNA methylation of perennial ryegrass under drought using the methylation-sensitive amplification polymorphism (MSAP) technique.

Science.gov (United States)

Tang, Xiao-Mei; Tao, Xiang; Wang, Yan; Ma, Dong-Wei; Li, Dan; Yang, Hong; Ma, Xin-Rong

2014-12-01

Perennial ryegrass (Lolium perenne), an excellent grass for forage and turf, is widespread in temperate regions. Drought is an important factor that limits its growth, distribution, and yield. DNA methylation affects gene expression and plays an important role in adaptation to adverse environments. In this study, the DNA methylation changes in perennial ryegrass under drought stress were assessed using methylation-sensitive amplified polymorphism (MSAP). After 15 days of drought stress treatment, the plant height was less than half of the control, and the leaves were smaller and darker. Genome-wide, a total of 652 CCGG sites were detected by MSAP. The total methylation level was 57.67 and 47.39 % in the control and drought treatment, respectively, indicating a decrease of 10.28 % due to drought exposure. Fifteen differentially displayed DNA fragments in MSAP profiles were cloned for sequencing analysis. The results showed that most of the genes involved in stress responses. The relative expression levels revealed that three demethylated fragments were up-regulated. The expression of a predicted retrotransposon increased significantly, changing from hypermethylation to non-methylation. Although the extent of methylation in two other genes decreased, the sites of methylation remained, and the expression increased only slightly. All of these results suggested that drought stress decreased the total DNA methylation level in perennial ryegrass and demethylation up-regulated related gene expressions and that the extent of methylation was negatively correlated with expression. Overall, the induced epigenetic changes in genome probably are an important regulatory mechanism for acclimating perennial ryegrass to drought and possibly other environmental stresses.

Microwave-assisted pyrolysis of methyl ricinoleate for continuous production of undecylenic acid methyl ester (UAME).

Science.gov (United States)

Nie, Yong; Duan, Ying; Gong, Ruchao; Yu, Shangzhi; Lu, Meizhen; Yu, Fengwen; Ji, Jianbing

2015-06-01

Undecylenic acid methyl ester (UAME) was continuously produced from methyl ricinoleate using a microwave-assisted pyrolysis system with atomization feeding. The UAME yield of 77 wt.% was obtained at 500°C using SiC as the microwave absorbent and heating medium. The methyl ricinoleate conversion and UAME yield from microwave-assisted pyrolysis process were higher than those from conventional pyrolysis. The effect of temperature on the pyrolysis process was also investigated. The methyl ricinoleate conversion increased but the cracking liquid yield decreased when the temperature increased from 460°C to 560°C. The maximum UAME yield was obtained at the temperature of 500°C. Copyright © 2015 Elsevier Ltd. All rights reserved.

Wind tunnel test of musi VI bridge

Science.gov (United States)

Permata, Robby; Andika, Matza Gusto; Syariefatunnisa, Risdhiawan, Eri; Hermawan, Budi; Noordiana, Indra

2017-11-01

Musi VI Bridge is planned to cross the Musi River in Palembang City, South Sumatera Province, Indonesia. The main span is a steel arch type with 200 m length and side span length is 75 m. Finite element analysis results showed that the bridge has frequency ratio for torsional and heaving mode (torsional frequency/heaving frequency)=1.14. This close to unity value rises concern about aerodynamic behaviour and stability of the bridge deck under wind loading. Sectional static and free vibration wind tunnel test were performed to clarify this phenomena in B2TA3 facility in Serpong, Indonesia. The test followed the draft of Guide of Wind Tunnel Test for Bridges developed by Indonesian Ministry of Public Works. Results from wind tunnel testing show that the bridge is safe from flutter instability and no coupled motion vibration observed. Therefore, low value of frequency ratio has no effect to aerodynamic behaviour of the bridge deck. Vortex-induced vibration in heaving mode occurred in relatively low wind velocity with permissible maximum amplitude value.

Methanol, Ethanol and Propanol in EHD liquid bridging

International Nuclear Information System (INIS)

Fuchs, Elmar C; Wexler, Adam D; Agostinho, Luewton L F; Ramek, Michael; Woisetschläger, Jakob

2011-01-01

When a high-voltage direct-current is applied to two beakers filled with water or polar liquid dielectrica, a horizontal bridge forms between the two beakers. In this work such bridges made of methanol, ethanol, 1-propanol and 2-propanol are investigated with polarimetry and thermography. Whereas methanol, ethanol and 1-propanol bridges become warm like a water bridge, a 2-propanol bridge cools down relative to the surroundings. It is shown how the different stability of the primary and secondary alcoholate ions and the resulting small difference in conductivity between 1-propanol and 2-propanol is responsible for this novel effect.

The shape, stability and breakage of pendant liquid bridges

Science.gov (United States)

Padday, J. F.; Pétré, G.; Rusu, C. G.; Gamero, J.; Wozniak, G.

1997-12-01

Pendant liquid bridges are defined as pendant drops supporting a solid axisymmetric endplate at their lower end. The stability and shape properties of such bridges are defined in terms of the capillary properties of the system and of the mass and radius of the lower free-floating endplate. The forces acting in the pendant liquid bridge are defined exactly and expressed in dimensionless form. Numerical analysis has been used to derive the properties of a given bridge and it is shown that as the bridge grows by adding more liquid to the system a maximum volume is reached. At this maximum volume, the pendant bridge becomes unstable with the length of the bridge increasing spontaneously and irreversibly at constant volume. Finally the bridge breaks with the formation of a satellite drop or an extended thread. The bifurcation and breakage processes have been recorded using a high-speed video camera with a digital recording rate of up to 6000 frames per second. The details of the shape of the bridge bifurcation and breakage for many pendant bridge systems have been recorded and it is shown that satellite drop formation after rupture is not always viscosity dependent. Bifurcation and breakage in simulated low gravity demonstrated that breakage was very nearly symmetrical about a plane through the middle of the pendant bridge.

Seismic response computations for a long span bridge

International Nuclear Information System (INIS)

McCallen, D.B.

1994-01-01

The authors are performing large-scale numerical computations to simulate the earthquake response of a major long-span bridge that crosses the San Francisco Bay. The overall objective of the study is to estimate the response of the bridge to potential large-magnitude earthquakes generated on the nearby San Andreas and Hayward earthquake faults. Generation of a realistic model of the bridge system is complicated by the existence of large pile group foundations that extend deep into soft, saturated clay soils, and by the numerous expansion joints that segment the overall bridge structure. In the current study, advanced, nonlinear, finite element technology is being applied to rigorously model the detailed behavior of the bridge system and to shed light on the influence of the foundations and joints of the bridge

Quantitative DNA methylation analyses reveal stage dependent DNA methylation and association to clinico-pathological factors in breast tumors

International Nuclear Information System (INIS)

Klajic, Jovana; Tost, Jörg; Kristensen, Vessela N; Fleischer, Thomas; Dejeux, Emelyne; Edvardsen, Hege; Warnberg, Fredrik; Bukholm, Ida; Lønning, Per Eystein; Solvang, Hiroko; Børresen-Dale, Anne-Lise

2013-01-01

Aberrant DNA methylation of regulatory genes has frequently been found in human breast cancers and correlated to clinical outcome. In the present study we investigate stage specific changes in the DNA methylation patterns in order to identify valuable markers to understand how these changes affect breast cancer progression. Quantitative DNA methylation analyses of 12 candidate genes ABCB1, BRCCA1, CDKN2A, ESR1, GSTP1, IGF2, MGMT, HMLH1, PPP2R2B, PTEN, RASSF1A and FOXC1 was performed by pyrosequencing a series of 238 breast cancer tissue samples from DCIS to invasive tumors stage I to IV. Significant differences in methylation levels between the DCIS and invasive stage II tumors were observed for six genes RASSF1A, CDKN2A, MGMT, ABCB1, GSTP1 and FOXC1. RASSF1A, ABCB1 and GSTP1 showed significantly higher methylation levels in late stage compared to the early stage breast carcinoma. Z-score analysis revealed significantly lower methylation levels in DCIS and stage I tumors compared with stage II, III and IV tumors. Methylation levels of PTEN, PPP2R2B, FOXC1, ABCB1 and BRCA1 were lower in tumors harboring TP53 mutations then in tumors with wild type TP53. Z-score analysis showed that TP53 mutated tumors had significantly lower overall methylation levels compared to tumors with wild type TP53. Methylation levels of RASSF1A, PPP2R2B, GSTP1 and FOXC1 were higher in ER positive vs. ER negative tumors and methylation levels of PTEN and CDKN2A were higher in HER2 positive vs. HER2 negative tumors. Z-score analysis also showed that HER2 positive tumors had significantly higher z-scores of methylation compared to the HER2 negative tumors. Univariate survival analysis identifies methylation status of PPP2R2B as significant predictor of overall survival and breast cancer specific survival. In the present study we report that the level of aberrant DNA methylation is higher in late stage compared with early stage of invasive breast cancers and DCIS for genes mentioned above

The ectopic expression of a pectin methyl esterase inhibitor increases pectin methyl esterification and limits fungal diseases in wheat.

Science.gov (United States)

Volpi, Chiara; Janni, Michela; Lionetti, Vincenzo; Bellincampi, Daniela; Favaron, Francesco; D'Ovidio, Renato

2011-09-01

Cell wall pectin methyl esterification can influence plant resistance because highly methyl-esterified pectin can be less susceptible to the hydrolysis by pectic enzymes such as fungal endopolygalacturonases (PG). Pectin is secreted into the cell wall in a highly methyl-esterified form and, here, is de-methyl esterified by pectin methyl esterase (PME). The activity of PME is controlled by specific protein inhibitors called PMEI; consequently, an increased inhibition of PME by PMEI might modify the pectin methyl esterification. In order to test the possibility of improving wheat resistance by modifying the methyl esterification of pectin cell wall, we have produced durum wheat transgenic lines expressing the PMEI from Actinidia chinensis (AcPMEI). The expression of AcPMEI endows wheat with a reduced endogenous PME activity, and transgenic lines expressing a high level of the inhibitor showed a significant increase in the degree of methyl esterification. These lines showed a significant reduction of disease symptoms caused by the fungal pathogens Bipolaris sorokiniana or Fusarium graminearum. This increased resistance was related to the impaired ability of these fungal pathogens to grow on methyl-esterified pectin and to a reduced activity of the fungal PG to hydrolyze methyl-esterified pectin. In addition to their importance for wheat improvement, these results highlight the primary role of pectin despite its low content in the wheat cell wall.

Shear evaluation of tapered bridge girder panels with steel corrugated webs near the supports of continuous bridges

OpenAIRE

Zevallos, E.; Hassanein, M.F.; Real Saladrigas, Esther; Mirambell Arrizabalaga, Enrique

2016-01-01

Because of public construction budgets were cut over the last few years, new bridge girders with corrugated webs to reduce the construction costs have become more widely studied and used. In spite that tapered bridge girders with corrugated webs (BGCWs) are used in modern bridges, their shear strength and behaviour rarely exists in literature. Based on available literature, the web of the linearly tapered BGCWs may be divided into three typologies with different structural response to shear f...

Blasting detonators incorporating semiconductor bridge technology

Energy Technology Data Exchange (ETDEWEB)

Bickes, R.W. Jr.

1994-05-01

The enormity of the coal mine and extraction industries in Russia and the obvious need in both Russia and the US for cost savings and enhanced safety in those industries suggests that joint studies and research would be of mutual benefit. The author suggests that mine sites and well platforms in Russia offer an excellent opportunity for the testing of Sandia`s precise time-delay semiconductor bridge detonators, with the potential for commercialization of the detonators for Russian and other world markets by both US and Russian companies. Sandia`s semiconductor bridge is generating interest among the blasting, mining and perforation industries. The semiconductor bridge is approximately 100 microns long, 380 microns wide and 2 microns thick. The input energy required for semiconductor bridge ignition is one-tenth the energy required for conventional bridgewire devices. Because semiconductor bridge processing is compatible with other microcircuit processing, timing and logic circuits can be incorporated onto the chip with the bridge. These circuits can provide for the precise timing demanded for cast effecting blasting. Indeed tests by Martin Marietta and computer studies by Sandia have shown that such precise timing provides for more uniform rock fragmentation, less fly rock, reduce4d ground shock, fewer ground contaminants and less dust. Cost studies have revealed that the use of precisely timed semiconductor bridges can provide a savings of $200,000 per site per year. In addition to Russia`s vast mineral resources, the Russian Mining Institute outside Moscow has had significant programs in rock fragmentation for many years. He anticipated that collaborative studies by the Institute and Sandia`s modellers would be a valuable resource for field studies.

0-6722 : spread prestressed concrete slab beam bridges.

Science.gov (United States)

2014-08-01

The Texas Department of Transportation uses : precast prestressed concrete slab beam bridges for : shorter-span bridges of approximately 3050 ft in : length. Conventional slab beam bridges have slab : beams placed immediately adjacent to one anoth...

Building Bridges One Line at a Time

Science.gov (United States)

Grigsby, Cathy Murray

2012-01-01

In this article, first-grade students were taught the different kinds of lines that were part of the construction of various bridges--the curved lines of the arches of stone bridges, straight lines connecting the cables of a suspension bridge, vertical lines, horizontal lines, and so on. They gained practice in drawing structures and in fine brush…

SURVEY RESULTS AND TESTING OF RAILWAY BRIDGES

Directory of Open Access Journals (Sweden)

I. H. Haniiev

2010-03-01

Full Text Available The article is devoted to the survey and testing of railway bridges by the State Joint-Stock Railway Company «Uzbekiston Temir Yollari» («Uzbekistan Railways». It is stated that in the existing rules on determination of the capacity of bridges the recommendations on taking into account the cumulative deflection to the moment of technical diagnostics of spans on the bridge capacity are absent. The author states on the need to develop a method for determining the wear of spans on restriction of the residual deflection in the bridge floor slabs.

23 CFR 650.705 - Application for discretionary bridge funds.

Science.gov (United States)

2010-04-01

... 23 Highways 1 2010-04-01 2010-04-01 false Application for discretionary bridge funds. 650.705... TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Discretionary Bridge Candidate Rating Factor § 650.705 Application for discretionary bridge funds. Each year through its field offices, the FHWA will...

New conceptual design of portable bamboo bridge for emergency purposes

Science.gov (United States)

Musthaffa, A. A.; Nor, N. M.; Yusof, M. A.; Yuhazri, M. Y.

2018-02-01

Portable bridges serve as routes for troops during the military operations and the disaster relief operation. Nowadays, bamboo has been regarded as one of the alternative construction materials for building and bridge structures. This paper presents the conceptual design of the portable bridge. Several types of portable bridges and bamboo bridges are reviewed in the current work. The characteristics, capability and method of construction of each bridge are discussed. Finally, the conceptual of the portable bamboo bridge for emergency purposes is presented. The idea of producing portable bridge is proposed in the current work as it is crucial for providing route for communities affected by natural disasters.

A cloud-based information repository for bridge monitoring applications

Science.gov (United States)

Jeong, Seongwoon; Zhang, Yilan; Hou, Rui; Lynch, Jerome P.; Sohn, Hoon; Law, Kincho H.

2016-04-01

This paper describes an information repository to support bridge monitoring applications on a cloud computing platform. Bridge monitoring, with instrumentation of sensors in particular, collects significant amount of data. In addition to sensor data, a wide variety of information such as bridge geometry, analysis model and sensor description need to be stored. Data management plays an important role to facilitate data utilization and data sharing. While bridge information modeling (BrIM) technologies and standards have been proposed and they provide a means to enable integration and facilitate interoperability, current BrIM standards support mostly the information about bridge geometry. In this study, we extend the BrIM schema to include analysis models and sensor information. Specifically, using the OpenBrIM standards as the base, we draw on CSI Bridge, a commercial software widely used for bridge analysis and design, and SensorML, a standard schema for sensor definition, to define the data entities necessary for bridge monitoring applications. NoSQL database systems are employed for data repository. Cloud service infrastructure is deployed to enhance scalability, flexibility and accessibility of the data management system. The data model and systems are tested using the bridge model and the sensor data collected at the Telegraph Road Bridge, Monroe, Michigan.

The I-35W bridge Project Website

DEFF Research Database (Denmark)

Kampf, Constance

How can websites be used to rebuild trust?  In August 2007, the Interstate Highway 35-W bridge in Minneapolis, MN collapsed during rush hour.  Although many people were rescued and casualties were as limited as could be expected due to quick and effective intervention, the image of a major bridge...... collapsing during rush hour damaged the Minnesota Department of Transportation's reputation and resulted in the loss of public trust for the organization.  The ensuing bridge reconstruction project included a project website intended to rebuild this trust through transparency, community involvement......, and the use of multimodal features.  This paper looks at the I35-W bridge reconstruction project in Minneapolis through web-based communication by the Minnesota Department of Transportation (MnDOT) about the project. The MnDOT bridge reconstruction website will be examined using a combination of 1). Weick...

Cytosine methylation at CpCpG sites triggers accumulation of non-CpG methylation in gene bodies

OpenAIRE

Zabet, NR; Catoni, Marco; Prischi, F; Paszkowski, Jerzy Waclaw

2017-01-01

Methylation of cytosine is an epigenetic mark involved in the regulation of transcription, usually associated with transcriptional repression. In mammals, methylated cytosines are found predominantly in CpGs but in plants non-CpG methylation (in the CpHpG or CpHpH contexts, where H is A, C or T) is also present and is associated with the transcriptional silencing of transposable elements. In addition, CpG methylation is found in coding regions of active genes. In the absence of the demethylas...

Electron transfer reactions induced by the triplet state of thiacarbocyanine dimers

International Nuclear Information System (INIS)

Chibisov, Alexander K.; Slavnova, Tatyana D.; Goerner, Helmut

2004-01-01

The photoinduced electron transfer between either cationic 5,5 ' -dichloro-3,3 ' ,9-triethylthiacarbocyanine (1) or a structurally similar anionic dye (2) and appropriate donors, e.g. ascorbic acid, and acceptors, e.g. methyl viologen, was studied by ns-laser photolysis. In aqueous solution the dyes in the ground state are present as an equilibrated mixture of dimers and monomers, whereas the triplet state is mainly populated from dimers. The triplet states of both dimers and monomers are quenched by electron donors or acceptors and the rate constant for quenching is generally 2-4 times higher for dimers than for monomers. The kinetics of triplet decay and radical formation and decay as a result of primary and secondary electron transfer were analyzed. While the one-electron reduced dimer decays due to back reactions, the one-electron oxidized dimer rapidly dissociates into the monomer and the monomeric dye radical. For the dimeric dye/donor/acceptor systems the primary photoinduced electron transfer occurs either from the donor or to the acceptor yielding the dimeric dye radicals. The one-electron reduced dimer can be efficiently oxidized by acceptors, e.g. the rate constant for reaction of the dimeric dye radical of 1 with methyl viologen (photoreductive pathway of sensitization) is 1.6x10 9 M -1 s -1 . The photooxidative pathway of sensitization is more complicated; after dissociation of the dimeric dye radical, the monomeric dye radical is reduced in a secondary electron transfer from ascorbic acid, e.g. with a rate constant of 1x10 9 M -1 s -1 for 2, yielding the monomer. On increasing the donor concentration the photooxidative pathway of sensitization is switched to a photoreductive one

Investigation on the performance of bridge approach slab

Directory of Open Access Journals (Sweden)

Abdelrahman Amr

2018-01-01

Full Text Available In Egypt, where highway bridges are to be constructed on soft cohesive soils, the bridge abutments are usually founded on rigid piles, whereas the earth embankments for the bridge approaches are directly founded on the natural soft ground. Consequently, excessive differential settlement frequently occurs between the bridge deck and the bridge approaches resulting in a “bump” at both ends of the bridge deck. Such a bump not only creates a rough and uncomfortable ride but also represents a hazardous condition to traffic. One effective technique to cope with the bump problem is to use a reinforced concrete approach slab to provide a smooth grade transition between the bridge deck and the approach pavement. Investigating the geotechnical and structural performance of approach slabs and revealing the fundamental affecting factors have become mandatory. In this paper, a 2-D finite element model is employed to investigate the performance of approach slabs. Moreover, an extensive parametric study is carried out to appraise the relatively optimum geometries of approach slab, i.e. slab length, thickness, embedded depth and slope, that can yield permissible bumps. Different geo-mechanical conditions of the cohesive foundation soil and the fill material of the bridge embankment are examined.

miRNAting control of DNA methylation

Indian Academy of Sciences (India)

DNA methylation is a type of epigenetic modification where a methyl group is added to the cytosine or adenine residue of a given DNA sequence. It has been observed that DNA methylation is achieved by some collaborative agglomeration of certain proteins and non-coding RNAs. The assembly of IDN2 and its ...

History of cable-stayed bridges

DEFF Research Database (Denmark)

Gimsing, Niels Jørgen

1999-01-01

The principle of supporting a bridge deck by inclined tension members leading to towers on either side of the span has been known for centuries. However, the real development of cable-stayed bridges did not begin before the 1950s. Since then the free span has been increased from 183 m in the Strö...

Analysis of DNA Methylation of Gracilariopsis lemaneiformis Under Temperature Stress Using the Methylation Sensitive Amplification Polymorphism (MSAP) Technique

Science.gov (United States)

Peng, Chong; Sui, Zhenghong; Zhou, Wei; Hu, Yiyi; Mi, Ping; Jiang, Minjie; Li, Xiaodong; Ruan, Xudong

2018-06-01

Gracilariopsis lemaneiformis is an economically important agarophyte, which contains high quality gel and shows a high growth rate. Wild population of G. lemaneiformis displayed resident divergence, though with a low genetic diversity as was revealed by amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) analyses. In addition, different strains of G. lemaneiformis are diverse in morphology. The highly inconsistence between genetic background and physiological characteristics recommends strongly to the regulation at epigenetic level. In this study, the DNA methylation change in G. lemaneiformis among different generation branches and under different temperature stresses was assessed using methylation sensitive amplified polymorphism (MSAP) technique. It was shown that DNA methylation level among different generation branches was diverse. The full and total methylated DNA level was the lowest in the second generation branch and the highest in the third generation. The total methylation level was 61.11%, 60.88% and 64.12% at 15°C, 22°C and 26°C, respectively. Compared with the control group (22°C), the fully methylated and totally methylated ratios were increased in both experiment groups (15°C and 26°C). All of the cytosine methylation/demethylation transform (CMDT) was further analyzed. High temperature treatment could induce more CMDT than low temperature treatment did.

A Hierarchical Analysis of Bridge Decision Makers ... The Role of New Technology Adoption in the Timber Bridge Market: Special Project

Science.gov (United States)

Robert L. Smith; Robert J. Bush; Daniel L. Schmoldt

1995-01-01

Bridge design engineers and local highway officials make bridge replacement decisions across the United States. The Analytical Hierarchy Process was used to characterize the bridge material selection decision of these individuals. State Department of Transportation engineers, private consulting engineers, and local highway officials were personally interviewed in...

Intercellular bridges in vertebrate gastrulation.

Directory of Open Access Journals (Sweden)

Luca Caneparo

Full Text Available The developing zebrafish embryo has been the subject of many studies of regional patterning, stereotypical cell movements and changes in cell shape. To better study the morphological features of cells during gastrulation, we generated mosaic embryos expressing membrane attached Dendra2 to highlight cellular boundaries. We find that intercellular bridges join a significant fraction of epiblast cells in the zebrafish embryo, reaching several cell diameters in length and spanning across different regions of the developing embryos. These intercellular bridges are distinct from the cellular protrusions previously reported as extending from hypoblast cells (1-2 cellular diameters in length or epiblast cells (which were shorter. Most of the intercellular bridges were formed at pre-gastrula stages by the daughters of a dividing cell maintaining a membrane tether as they move apart after mitosis. These intercellular bridges persist during gastrulation and can mediate the transfer of proteins between distant cells. These findings reveal a surprising feature of the cellular landscape in zebrafish embryos and open new possibilities for cell-cell communication during gastrulation, with implications for modeling, cellular mechanics, and morphogenetic signaling.

Characterization of bridge foundations workshop report.

Science.gov (United States)

2013-11-01

"In 2013, the Federal Highway Administration proposed a new research program for the characterization of bridge foundations. To narrow the focus and develop a research roadmap for the program, a workshop on Characterization of Bridge Foundations...

An efficient CMOS bridging fault simulator with SPICE accuracy

NARCIS (Netherlands)

Di, C.; Jess, J.A.G.

1996-01-01

This paper presents an alternative modeling and simulation method for CMOS bridging faults. The significance of the method is the introduction of a set of generic-bridge tables which characterize the bridged outputs for each bridge and a set of generic-cell tables which characterize how each cell

33 CFR 118.110 - Daymarks and lateral lighting on bridges.

Science.gov (United States)

2010-07-01

... bridges. 118.110 Section 118.110 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.110 Daymarks and lateral lighting on bridges. (a... through bridges with U.S. aids to navigation system lateral marks and lights installed on the...

Some aspects of technical models within bridge management system

Directory of Open Access Journals (Sweden)

Grković Slobodan

2015-01-01

Full Text Available Bridge Management System (BMS represents a rational and systematic approach to organizing and conducting of all activities related to bridge maintenance. Main goal of BMS is helping the bridge owner to make an optimal decision with respect to bridge maintenance budget, whether it is dedicated to one bridge or to group of bridges, by securing that the decision is made on the basis of Life-Cycle Cost (LCC estimates. The structure of BMS is based on condition rating and Bridge Database (BD, Deterioration model (DM, Cost Model for evaluation of costs and Optimization Model for choosing the most rational maintenance strategy. Relationship between bridge condition rating and DM with maintenance costs within BMS is very important. Predictions regarding future intensity and rate of bridge deterioration depends on multitude of factors and it is a consequence of several simultaneous actions and deterioration processes (DP which need to be included into DMs. DMs are mostly based on modeling of physical and chemical actions and processes or they are based on statistical analysis of large number of data regarding the condition of existing bridges, or on artificial intelligence models, etc. Stochastic models based on Markov processes are applied within more advanced contemporary BMS. Due to social and economic circumstances and lack of financial resources over the last two decades in Republic of Serbia bridge maintenance was neglected and creation of BD was discontinued. The paper deliberates some aspects of technical models within BMS, with DMs being pointed out, development of BD within bridge maintenance in Republic of Serbia and it gives an overview of sophisticated BMS and current advances in this field.

Monitoring system of arch bridge for safety network management

Science.gov (United States)

Joo, Bong Chul; Yoo, Young Jun; Lee, Chin Hyung; Park, Ki Tae; Hwang, Yoon Koog

2010-03-01

Korea has constructed the safety management network monitoring test systems for the civil infrastructure since 2006 which includes airport structure, irrigation structure, railroad structure, road structure, and underground structure. Bridges among the road structure include the various superstructure types which are Steel box girder bridge, suspension bridge, PSC-box-girder bridge, and arch bridge. This paper shows the process of constructing the real-time monitoring system for the arch bridge and the measured result by the system. The arch type among various superstructure types has not only the structural efficiency but the visual beauty, because the arch type superstructure makes full use of the feature of curve. The main measuring points of arch bridges composited by curved members make a difference to compare with the system of girder bridges composited by straight members. This paper also shows the method to construct the monitoring system that considers the characteristic of the arch bridge. The system now includes strain gauges and thermometers, and it will include various sensor types such as CCTV, accelerometers and so on additionally. For the long term and accuracy monitoring, the latest optical sensors and equipments are applied to the system.

A Comparison of Limb-Socket Kinematics of Bone-Bridging and Non-Bone-Bridging Wartime Transtibial Amputations

Science.gov (United States)

2012-05-16

each successive loading interval. Subset analysis was performed on the basis of amputation type (bone bridging or non bone bridging) and suspension...fitting, patient care. Washington, DC: US Government Printing Office; 1969. 2. Ertl J. Uber amputationsstumpfe. Chirurg. 1949;20:218 24. 3. Pinto MA

Suspension Bridge Flutter for Girder with Separate Control Flaps

DEFF Research Database (Denmark)

Huynh, T.; Thoft-Christensen, Palle

Active vibration control of long span suspension bridge flutter using separated control flaps (SFSC) has shown to increase effectively the critical wind speed of bridges. In this paper, an SFSC calculation based on modal equations of the vertical and torsional motions of the bridge girder including...... the flaps is presented. The length of the flaps attached to the girder, the flap configuration and the flap rotational angles are parameters used to increase the critical wind speed of the bridge. To illustrate the theory a numerical example is shown for a suspension bridge of 1000m+2500m+1000m span based...... on the Great Belt Bridge streamlined girder....

Colorectal Cancer "Methylator Phenotype": Fact or Artifact?

Directory of Open Access Journals (Sweden)

Charles Anacleto

2005-04-01

Full Text Available It has been proposed that human colorectal tumors can be classified into two groups: one in which methylation is rare, and another with methylation of several loci associated with a "CpG island methylated phenotype (CIMP," characterized by preferential proximal location in the colon, but otherwise poorly defined. There is considerable overlap between this putative methylator phenotype and the well-known mutator phenotype associated with microsatellite instability (MSI. We have examined hypermethylation of the promoter region of five genes (DAPK, MGMT, hMLH1, p16INK4a, and p14ARF in 106 primary colorectal cancers. A graph depicting the frequency of methylated loci in the series of tumors showed a continuous, monotonically decreasing distribution quite different from the previously claimed discontinuity. We observed a significant association between the presence of three or more methylated loci and the proximal location of the tumors. However, if we remove from analysis the tumors with hMLH1 methylation or those with MSI, the significance vanishes, suggesting that the association between multiple methylations and proximal location was indirect due to the correlation with MSI. Thus, our data do not support the independent existence of the so-called methylator phenotype and suggest that it rather may represent a statistical artifact caused by confounding of associations.

Two high-frequency mutual inductance bridges with high resolution

NARCIS (Netherlands)

Flokstra, Jakob; Gerritsma, G.J.; Kreuwel, H.J.M.; van der Marel, L.C.

1980-01-01

Two mutual inductance bridges are described for operation up to about 100 kHz. Special attention is paid to the sensitivity and resolution of the bridges. Both bridges can be used to measure variations of about 10 pH in the mutual inductance. The first bridge consists of passive elements only

23 CFR 650.805 - Bridges not requiring a USCG permit.

Science.gov (United States)

2010-04-01

... 23 Highways 1 2010-04-01 2010-04-01 false Bridges not requiring a USCG permit. 650.805 Section 650... OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.805 Bridges not... permit is not required for bridge construction. This determination shall be made at an early stage of...

Using rotating liquid bridges as accelerometers

Energy Technology Data Exchange (ETDEWEB)

Montanero, J.M. [Universidad de Extremadura, Badajoz (Spain). Dept. de Electronica e Ingenieria Electromecanica; Cabezas, G.; Acero, J.; Zayas, F.

1999-07-01

Liquid bridges have recently been proposed as fluid accelerometers that could be used to measure very small inertial forces under microgravity conditions [Meseguer et al., microgravity sci. technol. IX/2 (1996)]. The essential idea is to infer the values of such inertial forces from the liquid bridge interface contour, whose shape obviously depends on the values of such forces (apart from the bridge volume and the geometry of the supporting disks). Following a similar procedure, in this paper we explore the use of rotating axisymmetric liquid bridges to measure the residual axial gravity and the rotation rate of the liquid bridge regarded as a solid body. In light off the difficulties involved in performing experiments on Earth, the role of empirical data is played by an accurate numerical solution of the Young-Laplace equation. The values of both the axial gravity and angular speed are obtained by fitting the approximate analytical expressions derived in this paper to the numerical solution of the Young-Laplace equation. The comparison between the predicted and actual values of the variables of interest shows a satisfactory agreement, supporting the suitability of the procedure. (orig.)

Advanced materials for control of post-earthquake damage in bridges

International Nuclear Information System (INIS)

Shrestha, Kshitij C; Saiidi, M Saiid; Cruz, Carlos A

2015-01-01

This paper presents analytical modeling to study the seismic response of bridge systems with conventional and advanced details. For validation, a 33 m quarter-scale model of a four-span bridge incorporating innovative materials and details seismically tested on the shake tables at the University of Nevada, Reno was taken. The bridge specimen involved use of advanced materials and details to reduce damage at plastic hinges and minimize residual displacements. A three-dimensional, nonlinear model incorporating the response of the innovative materials was developed to study the bridge response using the finite-element software OpenSees. Existing finite-element formulations were used to capture the response of the advanced materials used in the bridge. The analytical model was found to be able to reproduce comparable bent displacements and bent shear forces within reasonable accuracy. The validated model was further used to study different types of bridges under suite of scaled bi-directional near-fault ground motions. Comparisons were made on behavior of five different bridge types, first conventional reinforced concrete bridge, second post-tensioned column bridge, third bridge with elastomeric rubber elements at the plastic hinge zone, fourth bridge with nickel–titanium superelastic shape memory alloy (SMA) reinforcing bar and fifth bridge with CuAlMn superelastic SMA reinforcing bar. Both the SMA used bridges also utilized engineered cementitious composite element at the plastic hinge zone. The results showed effectiveness of the innovative interventions on the bridges in providing excellent recentering capabilities with minimal damage to the columns. (paper)

Building Bridges

DEFF Research Database (Denmark)

The report Building Bridges adresses the questions why, how and for whom academic audience research has public value, from the different points of view of the four working groups in the COST Action IS0906 Transforming Audiences, Transforming Societies – “New Media Genres, Media Literacy and Trust...... in the Media”, “Audience Interactivity and Participation”, “The Role of Media and ICT Use for Evolving Social Relationships” and “Audience Transformations and Social Integration”. Building Bridges is the result of an ongoing dialogue between the Action and non-academic stakeholders in the field of audience......, Brian O’Neill, Andra Siibak, Sascha Trültzsch-Wijnen, Nicoletta Vittadini, Igor Vobič and Frauke Zeller. Stakeholder feedback from: Michelle Arlotta (DeAgostini), Andreea M. Costache (Association of Consumers of Audiovisual Media in Catalonia/TAC), Francesco Diasio (AMARC Europe), Marius Dragomir (Open...

Mathematical bridges

CERN Document Server

Andreescu, Titu; Tetiva, Marian

2017-01-01

Building bridges between classical results and contemporary nonstandard problems, Mathematical Bridges embraces important topics in analysis and algebra from a problem-solving perspective. Blending old and new techniques, tactics and strategies used in solving challenging mathematical problems, readers will discover numerous genuine mathematical gems throughout that will heighten their appreciation of the inherent beauty of mathematics. Most of the problems are original to the authors and are intertwined in a well-motivated exposition driven by representative examples. The book is structured to assist the reader in formulating and proving conjectures, as well as devising solutions to important mathematical problems by making connections between various concepts and ideas from different areas of mathematics. Instructors and educators teaching problem-solving courses or organizing mathematics clubs, as well as motivated mathematics students from high school juniors to college seniors, will find Mathematical Bri...

Free energy landscape of a minimalist salt bridge model.

Science.gov (United States)

Li, Xubin; Lv, Chao; Corbett, Karen M; Zheng, Lianqing; Wu, Dongsheng; Yang, Wei

2016-01-01

Salt bridges are essential to protein stability and dynamics. Despite the importance, there has been scarce of detailed discussion on how salt bridge partners interact with each other in distinct solvent exposed environments. In this study, employing a recent generalized orthogonal space tempering (gOST) method, we enabled efficient molecular dynamics simulation of repetitive breaking and reforming of salt bridge structures within a minimalist salt-bridge model, the Asp-Arg dipeptide and thereby were able to map its detailed free energy landscape in aqueous solution. Free energy surface analysis shows that although individually-solvated states are more favorable, salt-bridge states still occupy a noticeable portion of the overall population. Notably, the competing forces, e.g. intercharge attractions that drive the formation of salt bridges and solvation forces that pull the charged groups away from each other, are energetically comparable. As the result, the salt bridge stability is highly tunable by local environments; for instance when local water molecules are perturbed to interact more strongly with each other, the population of the salt-bridge states is likely to increase. Our results reveal the critical role of local solvent structures in modulating salt-bridge partner interactions and imply the importance of water fluctuations on conformational dynamics that involves solvent accessible salt bridge formations. © 2015 The Protein Society.

Synthesis of N-methyl and N-11C-methyl spiperone by phase transfer catalysis in anhydrous solvent

International Nuclear Information System (INIS)

Omokawa, Hiroyoshi; Tanaka, Akira; Iio, Mayumi; Nishihara, Yoshiaki; Inoue, Osamu; Yamazaki, Toshio.

1985-01-01

Spiperone, a butyrophenone neuroleptic drug, has been used in binding studies of dopamine receptors. Langstrom et al. developed N- 11 C-methyl spiperone, and, in cooperate with Wagner et al., made it possible to visualize the distribution of dopamine receptors in the human brain in vivo. In this paper, we independently developed another synthetic method of N- 11 C-methyl spiperone using the phase transfer catalyst in an anhydrous solvent. Separation of the product is feasible only by passing the reactant solution through a Millipore filter and injecting it onto high pressure liquid chromatography (HPLC). The time required for the synthesis and purification of N- 11 C-methyl spiperone from 11 C-methyl iodide and spiperone was 20 min. Radiochemical yield exceeded 35 % against 11 C-methyl iodide without correcting decay of the radioactivity. (author)

Methylation profiling identified novel differentially methylated markers including OPCML and FLRT2 in prostate cancer.

Science.gov (United States)

Wu, Yu; Davison, Jerry; Qu, Xiaoyu; Morrissey, Colm; Storer, Barry; Brown, Lisha; Vessella, Robert; Nelson, Peter; Fang, Min

2016-04-02

To develop new methods to distinguish indolent from aggressive prostate cancers (PCa), we utilized comprehensive high-throughput array-based relative methylation (CHARM) assay to identify differentially methylated regions (DMRs) throughout the genome, including both CpG island (CGI) and non-CGI regions in PCa patients based on Gleason grade. Initially, 26 samples, including 8 each of low [Gleason score (GS) 6] and high (GS ≥7) grade PCa samples and 10 matched normal prostate tissues, were analyzed as a discovery cohort. We identified 3,567 DMRs between normal and cancer tissues, and 913 DMRs distinguishing low from high-grade cancers. Most of these DMRs were located at CGI shores. The top 5 candidate DMRs from the low vs. high Gleason comparison, including OPCML, ELAVL2, EXT1, IRX5, and FLRT2, were validated by pyrosequencing using the discovery cohort. OPCML and FLRT2 were further validated in an independent cohort consisting of 20 low-Gleason and 33 high-Gleason tissues. We then compared patients with biochemical recurrence (n=70) vs. those without (n=86) in a third cohort, and they showed no difference in methylation at these DMR loci. When GS 3+4 cases and GS 4+3 cases were compared, OPCML-DMR methylation showed a trend of lower methylation in the recurrence group (n=30) than in the no-recurrence (n=52) group. We conclude that whole-genome methylation profiling with CHARM revealed distinct patterns of differential DNA methylation between normal prostate and PCa tissues, as well as between different risk groups of PCa as defined by Gleason scores. A panel of selected DMRs may serve as novel surrogate biomarkers for Gleason score in PCa.

[Specific features of 2-methyl hydroxybenzene and 3-methyl hydroxybenzene distribution in the organism of warm-blooded animals].

Science.gov (United States)

Shormanov, B K; Grishenko, V K; Astashkina, A P; Elizarova, M K

2013-01-01

The present work was designed to study the specific features of 2-methyl hydroxybezene and 3-methyl hydroxybenzene distribution after intragastric administration of these toxicants to warm-blooded animals (rats). They were detected in the unmetabolized form in the internal organs and blood of the animals. The levels of 2-methyl hydroxybezene were especially high in the stomach and blood whereas the maximum content of 3-methyl hydroxybenzene was found in brain, blood, small intestines of the poisoned rats.

Photoproduction of hydrogen by membranes of green photosynthetic bacteria

Energy Technology Data Exchange (ETDEWEB)

Bernstein, J D; Olson, J M

1980-01-01

Photoproduction of H/sub 2/ from ascorbate by unit-membrane vesicles from Chlorobium limicola f. thiosulfatophilum was achieved with a system containing gramicidin D, tetramethyl-p-phenylenediamine, methyl viologen, dithioerythritol, Clostridium hydrogenase, and an oxygen-scavenging mixture of glucose, glucose oxidase, ethanol, and catalase. Maximum quantum yield was less than one percent. Half maximum rate of H/sub 2/ production occurred at a white-light intensity of approximately 0.15 cm/sup -2/. The reaction was inhibited completely by 0.3% sodium dodecylbenzene sulfonate, 1% Triton X-100, or preheating the vesicles at 100/sup 0/C for 5 minutes. Low concentrations (0.01 and 0.05%) of Triton X-100 about doubled the reaction rate.

Pulse-radiolytic one-electron reduction of anthraquinone and chloro-anthraquinones in aqueous-isopropanol-acetone mixed solvent

International Nuclear Information System (INIS)

Rath, M.C.; Pal, H.; Mukherjee, T.

1996-01-01

One-electron reduction of 9,10-anthraquinone and some chloro-anthraquinones and the characteristics of the semiquinones thus formed have been investigated in aqueous-isipropanol-acetone mixed solvent using electron pulse radiolysis technique. Spectroscopic characteristics, kinetic parameters of formation and decay, and the acid/base behaviour of the semiquinones have been investigated. The one-electron reduction potential of the quinones have been measured following electron transfer equilibria with a reference redox system (methyl viologen) and the values thus obtained have been compared with those of some other anthrasemiquinone systems. An analysis of the characteristics of the semiquinones shows that α-chloro substituents adjacent to the C=O group act as electron withdrawing groups. (author)

Genome-wide DNA methylation maps in follicular lymphoma cells determined by methylation-enriched bisulfite sequencing.

Directory of Open Access Journals (Sweden)

Jeong-Hyeon Choi

Full Text Available BACKGROUND: Follicular lymphoma (FL is a form of non-Hodgkin's lymphoma (NHL that arises from germinal center (GC B-cells. Despite the significant advances in immunotherapy, FL is still not curable. Beyond transcriptional profiling and genomics datasets, there currently is no epigenome-scale dataset or integrative biology approach that can adequately model this disease and therefore identify novel mechanisms and targets for successful prevention and treatment of FL. METHODOLOGY/PRINCIPAL FINDINGS: We performed methylation-enriched genome-wide bisulfite sequencing of FL cells and normal CD19(+ B-cells using 454 sequencing technology. The methylated DNA fragments were enriched with methyl-binding proteins, treated with bisulfite, and sequenced using the Roche-454 GS FLX sequencer. The total number of bases covered in the human genome was 18.2 and 49.3 million including 726,003 and 1.3 million CpGs in FL and CD19(+ B-cells, respectively. 11,971 and 7,882 methylated regions of interest (MRIs were identified respectively. The genome-wide distribution of these MRIs displayed significant differences between FL and normal B-cells. A reverse trend in the distribution of MRIs between the promoter and the gene body was observed in FL and CD19(+ B-cells. The MRIs identified in FL cells also correlated well with transcriptomic data and ChIP-on-Chip analyses of genome-wide histone modifications such as tri-methyl-H3K27, and tri-methyl-H3K4, indicating a concerted epigenetic alteration in FL cells. CONCLUSIONS/SIGNIFICANCE: This study is the first to provide a large scale and comprehensive analysis of the DNA methylation sequence composition and distribution in the FL epigenome. These integrated approaches have led to the discovery of novel and frequent targets of aberrant epigenetic alterations. The genome-wide bisulfite sequencing approach developed here can be a useful tool for profiling DNA methylation in clinical samples.

Modeling spatiotemporal dynamics of DNA methylation

DEFF Research Database (Denmark)

Lövkvist, Cecilia Elisabet

into how epigenetic marks are distributed in the human genome. In the first part of the thesis, we investigate DNA methylation and maintenance of methylation patterns throughout cell division. We argue that collaborative models, those where the methylation of CpG sites depends on the methylation status...... into the game more explicitly in another type of model that speaks out the duality of the two aspects. Using statistical analysis of experimental data, this thesis further explores a link between DNA methylation and nucleosome occupancy. By comparing the patterns on promoters to regions with similar Cp...... division. The patterns of epigentic marks depend on enzymes that ensure their maintenance and introduction. Using theoretical models, this thesis proposes new mechanisms for how enzymes operate to maintain patterns of epigenetic marks. Through analysis of experimental data this work gives new insight...

STUDY OF BRIDGE DECK A REVIEW

OpenAIRE

MISS. KSHITIJA S. BALWAN , MR. V. G. KHURD , MR. S. S. CHOUGULE

2018-01-01

The objective of this study was to understand the meaning of bridge deck. To know the different forms of decks used in bridge design. To understand different methods used for analysis of deck and study of box girder and its evolution

Experimental and chemical kinetic modeling study of small methyl esters oxidation: Methyl (E)-2-butenoate and methyl butanoate

Energy Technology Data Exchange (ETDEWEB)

Gail, S.; Sarathy, S.M.; Thomson, M.J. [Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, ON M5S 3G8 (Canada); Dievart, P.; Dagaut, P. [CNRS, 1C, Ave de la Recherche Scientifique, 45071 Orleans Cedex 2 (France)

2008-12-15

This study examines the effect of unsaturation on the combustion of fatty acid methyl esters (FAME). New experimental results were obtained for the oxidation of methyl (E)-2-butenoate (MC, unsaturated C{sub 4} FAME) and methyl butanoate (MB, saturated C{sub 4} FAME) in a jet-stirred reactor (JSR) at atmospheric pressure under dilute conditions over the temperature range 850-1400 K, and two equivalence ratios ({phi}=0.375,0.75) with a residence time of 0.07 s. The results consist of concentration profiles of the reactants, stable intermediates, and final products, measured by probe sampling followed by on-line and off-line gas chromatography analyses. The oxidation of MC and MB in the JSR and under counterflow diffusion flame conditions was modeled using a new detailed chemical kinetic reaction mechanism (301 species and 1516 reactions) derived from previous schemes proposed in the literature. The laminar counterflow flame and JSR (for {phi}=1.13) experimental results used were from a previous study on the comparison of the combustion of both compounds. Sensitivity analyses and reaction path analyses, based on rates of reaction, were used to interpret the results. The data and the model show that MC has reaction pathways analogous to that of MB under the present conditions. The model of MC oxidation provides a better understanding of the effect of the ester function on combustion, and the effect of unsaturation on the combustion of fatty acid methyl ester compounds typically found in biodiesel. (author)

Strategic Planning for the National Bridge Stock of Iran

Directory of Open Access Journals (Sweden)

Ali Sahrapeyma

2013-06-01

Full Text Available The National Bridge Stock of Iran consists of about 330,000 bridges, of which around 50% are older than 30 years. Since 2010, Iran Road Maintenance & Transportation Organization has started implementing a comprehensive Bridge Management System in order to manage this aged stock efficiently. To predict future conditions of bridge stock, a heuristic numerical method is presented. This methodology is based on Markovian process to model deterioration of bridge decks and a multi-objective optimization problem to find the best solutions. The optimization problem involves three decision variables regarding management strategies, and has three objectives regarding cost minimization. Constraints of the problem are the percentage of deficient bridges, the percentage of bridges under MR&Rs (Maintenance, Repair and Rehabilitation and the average value of condition scores. The results show that to avoid future challenges, the annual budget for bridge maintenance should be increased, the current maintenance strategy should be improved as soon as possible, and national manuals and instructions for inspection, condition rating and maintenance should be developed.

Foot force models of crowd dynamics on a wobbly bridge.

Science.gov (United States)

Belykh, Igor; Jeter, Russell; Belykh, Vladimir

2017-11-01

Modern pedestrian and suspension bridges are designed using industry standard packages, yet disastrous resonant vibrations are observed, necessitating multimillion dollar repairs. Recent examples include pedestrian-induced vibrations during the opening of the Solférino Bridge in Paris in 1999 and the increased bouncing of the Squibb Park Bridge in Brooklyn in 2014. The most prominent example of an unstable lively bridge is the London Millennium Bridge, which started wobbling as a result of pedestrian-bridge interactions. Pedestrian phase locking due to footstep phase adjustment is suspected to be the main cause of its large lateral vibrations; however, its role in the initiation of wobbling was debated. We develop foot force models of pedestrians' response to bridge motion and detailed, yet analytically tractable, models of crowd phase locking. We use biomechanically inspired models of crowd lateral movement to investigate to what degree pedestrian synchrony must be present for a bridge to wobble significantly and what is a critical crowd size. Our results can be used as a safety guideline for designing pedestrian bridges or limiting the maximum occupancy of an existing bridge. The pedestrian models can be used as "crash test dummies" when numerically probing a specific bridge design. This is particularly important because the U.S. code for designing pedestrian bridges does not contain explicit guidelines that account for the collective pedestrian behavior.

Hierarchical analysis of bridge decision makers : the role of new technology adoption in the timber bridge market : special project fiscal year 1992

Science.gov (United States)

1995-08-01

Bridge design engineers and local highway officials make bridge replacement decisions across the : United States. The Analytical Hierarchy Process was used to characterize the bridge material selection : decision of these individuals. State Departmen...

Application of bridging-law concepts to short-fibre composites

DEFF Research Database (Denmark)

Lindhagen, J.E.; Gamstedt, Kristofer; Berglund, L.A.

2000-01-01

This is the third paper in a series of four where notch sensitivity, fracture energy and bridging laws are studied in short-fibre polymer composites. Here, bridging laws are derived from experimental crack-opening profiles in centre-hole notched tensile specimens. The materials studied are three...... types of commercial glass-mat composites with different reinforcement structures and matrices. The materials have softening bridging laws and the calculated fracture energies from bridging laws are in good agreement with values determined directly by experiment. The calculated maximum local bridging...

GaggleBridge: collaborative data analysis.

Science.gov (United States)

Battke, Florian; Symons, Stephan; Herbig, Alexander; Nieselt, Kay

2011-09-15

Tools aiding in collaborative data analysis are becoming ever more important as researchers work together over long distances. We present an extension to the Gaggle framework, which has been widely adopted as a tool to enable data exchange between different analysis programs on one computer. Our program, GaggleBridge, transparently extends this functionality to allow data exchange between Gaggle users at different geographic locations using network communication. GaggleBridge can automatically set up SSH tunnels to traverse firewalls while adding some security features to the Gaggle communication. GaggleBridge is available as open-source software implemented in the Java language at http://it.inf.uni-tuebingen.de/gb. florian.battke@uni-tuebingen.de Supplementary data are available at Bioinformatics online.

Seismic Performance of Multi-Span RC Railway Bridges

DEFF Research Database (Denmark)

Georgakis, Christos; Barrau, Xavier