WorldWideScience

Sample records for bicyclic heterocycles application

  1. Vapor pressures and sublimation enthalpies of novel bicyclic heterocycle derivatives

    International Nuclear Information System (INIS)

    Blokhina, Svetlana V.; Ol’khovich, Marina V.; Sharapova, Angelica V.; Perlovich, German L.; Proshin, Alexey N.

    2014-01-01

    Highlights: • The vapor pressures of novel bicyclo-derivatives of amine were measured. • Thermodynamic functions of sublimation were calculated. • The influence of substituent structure and chemical nature on the vapor pressure was studied. -- Abstract: The vapor pressures of five novel bicyclic heterocycle derivatives were measured over the temperature 341.15 to 396.15 K using the transpiration method by means of an inert gas carrier. From these results the standard enthalpies and Gibbs free energies of sublimation at the temperature 298.15 K were calculated. The effects of alkyl- and chloro-substitutions on changes in the thermodynamic functions have been investigated. Quantitative structure–property relationship on the basis HYBOT physico-chemical descriptors for biologically active compounds have been developed to predict the sublimation enthalpies and Gibbs free energies of the compounds studied

  2. Does the Intramolecular Hydrogen Bond Affect the Spectroscopic Properties of Bicyclic Diazole Heterocycles?

    Directory of Open Access Journals (Sweden)

    Paweł Misiak

    2018-01-01

    Full Text Available The formation of an intramolecular hydrogen bond in pyrrolo[1,2-a]pyrazin-1(2H-one bicyclic diazoles was analyzed, and the influence of N-substitution on HB formation is discussed in this study. B3LYP/aug-cc-pVDZ calculations were performed for the diazole, and the quantum theory of atoms in molecules (QTAIM approach as well as the natural bond orbital (NBO method was applied to analyze the strength of this interaction. It was found that the intramolecular hydrogen bond that closes an extra ring between the C=O proton acceptor group and the CH proton donor, that is, C=O⋯H–C, influences the spectroscopic properties of pyrrolopyrazine bicyclic diazoles, particularly the carbonyl frequencies. The influence of N-substitution on the aromaticity of heterocyclic rings is also discussed in this report.

  3. Differential specificity in the glomerular response profiles for alicyclic, bicyclic and heterocyclic odorants

    Science.gov (United States)

    Johnson, Brett A.; Xu, Zhe; Pancoast, Paige; Kwok, Jennifer; Ong, Joan; Leon, Michael

    2008-01-01

    As part of our ongoing effort to relate stimulus to response in the olfactory system, we tested the hypothesis that the unique chemical structures and odors of various cyclic odorants would be associated with unique spatial response patterns in the glomerular layer of the rat olfactory bulb. To this end, rats were exposed to sets of odorants including monocyclic hydrocarbons, bicyclic compounds, and various heterocyclic structures containing oxygen or nitrogen in the ring. Relative activity across the entire layer was assessed by mapping uptake of 2-deoxyglucose into anatomically standardized data matrices. Whereas monocyclic hydrocarbons evoked patterns similar to those evoked by open-chained hydrocarbon odorants, a set of bicyclic compounds with structures and odors similar to camphor evoked uptake in paired ventral domains not previously associated with any other odorant chemical structures. Despite their unique odors as judged by humans, heterocyclic odorants either evoked uptake in previously characterized areas corresponding to their functional groups or stimulated weak or patchy patterns involving isolated glomeruli. While the patchiness of the patterns may be partly related to the rigidity of the compounds, which would be expected to restrict their interactions to only a few receptors, the weakness of the patterns suggests the possibility of species-specific odorant representations. We conclude that whereas some of the novel cyclic structures indeed were represented by unique patterns in the rat bulb, other unique structures were poorly represented, even when they evoked intense and unique odors in humans. PMID:16958095

  4. Big Bicycle Data Processing: from Personal Data to Urban Applications

    Science.gov (United States)

    Pettit, C. J.; Lieske, S. N.; Leao, S. Z.

    2016-06-01

    Understanding the flows of people moving through the built environment is a vital source of information for the planners and policy makers who shape our cities. Smart phone applications enable people to trace themselves through the city and these data can potentially be then aggregated and visualised to show hot spots and trajectories of macro urban movement. In this paper our aim is to develop procedures for cleaning, aggregating and visualising human movement data and translating this into policy relevant information. In conducting this research we explore using bicycle data collected from a smart phone application known as RiderLog. We focus on the RiderLog application initially in the context of Sydney, Australia and discuss the procedures and challenges in processing and cleaning this data before any analysis can be made. We then present some preliminary map results using the CartoDB online mapping platform where data are aggregated and visualised to show hot spots and trajectories of macro urban movement. We conclude the paper by highlighting some of the key challenges in working with such data and outline some next steps in processing the data and conducting higher volume and more extensive analysis.

  5. Heterocyclic Nanographenes and Other Polycyclic Heteroaromatic Compounds: Synthetic Routes, Properties, and Applications.

    Science.gov (United States)

    Stępień, Marcin; Gońka, Elżbieta; Żyła, Marika; Sprutta, Natasza

    2017-02-22

    Two-dimensionally extended, polycyclic heteroaromatic molecules (heterocyclic nanographenes) are a highly versatile class of organic materials, applicable as functional chromophores and organic semiconductors. In this Review, we discuss the rich chemistry of large heteroaromatics, focusing on their synthesis, electronic properties, and applications in materials science. This Review summarizes the historical development and current state of the art in this rapidly expanding field of research, which has become one of the key exploration areas of modern heterocyclic chemistry.

  6. Design Analysis And Applications Of A Regenerative Bicycle Ergometer

    Directory of Open Access Journals (Sweden)

    Chukwuneke J. L.

    2015-08-01

    Full Text Available Man needs to do some form of physical work in other to remain healthy this work is similar to the work done by any machine or equipment and thus should be channeled to give useful output but rather it is usually dissipated into the environment in form of heat. The regenerative bicycle ergometer takes advantage of the greater power generated by the limbs and arms thus conserves converts and stores the energy dissipated by the rider with an ideal mechanical advantage of 7.6 it strategically uses simple mechanisms to magnify its work and then converts this mechanical energy into electrical energy by the use of a dynamo with a speed ratio of 108.5 and a transmission efficiency of 89 the rider pedals 27rpm to obtain the dynamos rated input of 2600rpm giving an output of 12.6volts. The regenerative bicycle ergometer is designed and constructed to perform all the core functions of a bicycle ergometer having an allowable load of 116.5kg and a maximum resistance of 65.33N which is equivalent to a mass of 6.66kg. The energy converted is stored in a 12volts battery making its use flexible clean and meeting the energy demands of man.

  7. Generation of Polar Semi-Saturated Bicyclic Pyrazoles for Fragment-Based Drug Discovery Campaigns.

    Science.gov (United States)

    Luise, Nicola; Wyatt, Paul

    2018-05-07

    Synthesising polar semi-saturated bicyclic heterocycles can lead to better starting points for fragment-based drug discovery (FBDD) programs. This communication highlights the application of diverse chemistry to construct bicyclic systems from a common intermediate, where pyrazole, a privileged heteroaromatic able to bind effectively to biological targets, is fused to diverse saturated counterparts. The generated fragments can be further developed either after confirmation of their binding pose or early in the process, as their synthetic intermediates. Essential quality control (QC) for selection of small molecules to add to a fragment library is discussed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Heterocyclic Naphthalimides as New Skeleton Structure of Compounds with Increasingly Expanding Relational Medicinal Applications.

    Science.gov (United States)

    Gong, Huo-Hui; Addla, Dinesh; Lv, Jing-Song; Zhou, Cheng-He

    2016-01-01

    Naphthalimide compounds are an important type of nitrogen-containing aromatic heterocycles with cyclic double imides and the naphthalene framework. This π-deficient large conjugated planar structure enables naphthalimide derivatives to readily interact with various biological cations, anions, small molecules and macromolecules such as DNAs, enzymes and recetors in living organism via noncovalent bonds, therefore exhibiting extensive potentiality in relatively medicinal applications. Currently, some naphthalimides as anticancer agents have entered into clinical trials and other naphthalimide-based medicinal developments as potential drugs for treatment of various diseases are actively and unprecedentedly expanding. Naphthalimide-derived artificial ion receptors, fluorescent probes and cell imaging agents are being overwhelmingly investigated and have a diversity of potential applications in real-time detecting ions and biomolecules, understanding biological processes and determining pharmacological and pharmacokinetic properties. All the above mentions have strongly implied that naphthalimide-based derivatives as new skeleton structure of compounds possess increasingly expanding relational medicinal applications, and the related research is becoming a quite attractive active topic and newly rising highlight. Combining with our research and referring other works from literature, this work systematically reviews the current research and development of heterocyclic naphthalimides as anticancer, antibacterial, antifungal, antiviral, anti-inflammatory, antidepressant agents as well as artificial cation and anion receptors, diagnostic agents and pathologic probes, and cell imaging agents for biologically important species. Some rational design strategies, structure-activity relationships and action mechanisms are discussed. The perspectives of the future development of naphthalimide-based medicinal chemistry are also presented.

  9. Bicycle Crashes

    Data.gov (United States)

    Town of Chapel Hill, North Carolina — This data set maps the locations of crashes involving bicyclists in the Chapel Hill Region of North Carolina.The data comes from police-reported bicycle-motor...

  10. Handbook of heterocyclic chemistry

    National Research Council Canada - National Science Library

    Katritzky, Alan R

    2010-01-01

    ... Heterocyclic Chemistry I (1984) Comprehensive Heterocyclic Chemistry II (1996) Comprehensive Heterocyclic Chemistry III (2008) Comprehensive Organic Functional Group Transformations I (1995) Compreh...

  11. Cytotoxic effects of chemotherapeutic drugs and heterocyclic compounds at application on the cells of primary culture of neuroepithelium tumors.

    Science.gov (United States)

    Kulchitsky, Vladimir A; Potkin, Vladimir I; Zubenko, Yuri S; Chernov, Alexander N; Talabaev, Michael V; Demidchik, Yuri E; Petkevich, Sergei K; Kazbanov, Vladimir V; Gurinovich, Tatiana A; Roeva, Margarita O; Grigoriev, Dmitry G; Kletskov, Alexei V; Kalunov, Vladimir N

    2012-01-01

    Neuroepithelial tumor cells were cultured in vitro. The biopsy material was taken from 93 children at removal of the brain tumors during neurosurgical operations. The individual features of the cells sensitivity of primary cultures in respect to protocol-approved chemotherapy drugs and changes in the Interleukin-6 (Il-6) level in the culture medium after the application of chemotherapy were established. The initial level of Il-6 exceeded 600.0 pg/ml in the cultural medium with histologically verified pilomyxoid astrocytoma cells, and ranged from 100.0 to 200.0 pg/ml in the medium at cultivation of ganglioneuroblastoma and pilocytic astrocytoma. A decrease in the Il-6 level in the medium culture of primary tumors cells was observed after the application of chemotherapeutic agents on the cells of pilomyxoid astrocytoma, astrocytomas, and pilocytic desmoplastic/nodular medulloblastoma. The production of Il-6 increased after application of cytostatic drugs on the cells of oligoastrocytomas. A decrease in Il-6 level after application of Cisplatin and Methotrexate and a 5-10 fold increase in the level of Il-6 after application of Etoposide, Carboplatin, Cytarabine, and Gemcitabine were registered in the medium with ganglioneuroblastoma. To improve the cytotoxic action of chemotherapeutic agents, the combined application of cytostatics with heterocyclic compounds was carried out. A computer modeling of ligand-protein complexes of carbamide using the Dock 6.4 and USF Chimera program packages was performed with molecular mechanics method. Special attention was drawn to the ability of several isoxazole heterocycles and isothiazolyl to inhibit the tyrosine kinase. It was proved in vitro that the joint application of chemotherapeutic agents and heterocyclic compounds could reduce the concentration of the cytostatic factor by 10 or more times, having maintained the maximum cytotoxic effect. It was assumed that the target amplification of cytotoxic action of chemotherapeutic

  12. Design Comparison of Inner and Outer Rotor of Permanent Magnet Flux Switching Machine for Electric Bicycle Application

    Science.gov (United States)

    Jusoh, L. I.; Sulaiman, E.; Bahrim, F. S.; Kumar, R.

    2017-08-01

    Recent advancements have led to the development of flux switching machines (FSMs) with flux sources within the stators. The advantage of being a single-piece machine with a robust rotor structure makes FSM an excellent choice for speed applications. There are three categories of FSM, namely, the permanent magnet (PM) FSM, the field excitation (FE) FSM, and the hybrid excitation (HE) FSM. The PMFSM and the FEFSM have their respective PM and field excitation coil (FEC) as their key flux sources. Meanwhile, as the name suggests, the HEFSM has a combination of PM and FECs as the flux sources. The PMFSM is a simple and cheap machine, and it has the ability to control variable flux, which would be suitable for an electric bicycle. Thus, this paper will present a design comparison between an inner rotor and an outer rotor for a single-phase permanent magnet flux switching machine with 8S-10P, designed specifically for an electric bicycle. The performance of this machine was validated using the 2D- FEA. As conclusion, the outer-rotor has much higher torque approximately at 54.2% of an innerrotor PMFSM. From the comprehensive analysis of both designs it can be conclude that output performance is lower than the SRM and IPMSM design machine. But, it shows that the possibility to increase the design performance by using “deterministic optimization method”.

  13. Fusing porphyrins with polycyclic aromatic hydrocarbons and heterocycles for optoelectronic applications

    Science.gov (United States)

    Thompson, Mark E.; Diev, Viacheslav; Hanson, Kenneth; Forrest, Stephen R.

    2015-08-18

    A compound that can be used as a donor material in organic photovoltaic devices comprising a non-activated porphyrin fused with one or more non-activated polycyclic aromatic rings or one or more non-activated heterocyclic rings can be obtained by a thermal fusion process. The compounds can include structures of Formula I: ##STR00001## By heating the reaction mixture of non-activated porphyrins with non-activated polycyclic aromatic rings or heterocyclic rings to a fusion temperature and holding for a predetermined time, fusion of one or more polycyclic rings or heterocyclic rings to the non-activated porphyrin core in meso,.beta. fashion is achieved resulting in hybrid structures containing a distorted porphyrin ring with annulated aromatic rings. The porphyrin core can be olygoporphyrins.

  14. New chiral zwitterionic phosphorus heterocycles: synthesis, structure, properties and application as chiral solvating agents.

    Science.gov (United States)

    Sheshenev, Andrey E; Boltukhina, Ekaterina V; Grishina, Anastasiya A; Cisařova, Ivana; Lyapkalo, Ilya M; Hii, King Kuok Mimi

    2013-06-17

    A family of new chiral zwitterionic phosphorus-containing heterocycles (zPHC) have been derived from methylene-bridged bis(imidazolines). These structures were unambiguously determined, including single-crystal XRD analysis for two compounds. The stability, acid/base and electronic properties of these dipolar phosphorus heterocycles were subsequently investigated. zPHCs can be successfully employed as a new class of chiral solvating agents for the enantiodifferentiation of chiral carboxylic and sulfonic acids by NMR spectroscopy. The stoichiometry and binding constants for the donor-acceptor complexes formed were established by NMR titration methods. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Greener Synthesis of N-Heterocycles via Sustainable Applications of Nano-Catalysts

    Science.gov (United States)

    A brief historic account of reactions involving microwave (MW) exposure of neat reactants or catalysis by mineral surfaces, such as alumina, silica, clay, or their ‘doped’ versions, for the rapid one-pot assembly of heterocyclic compounds from in situ generated reactive intermedi...

  16. New Chiral Zwitterionic Phosphorus Heterocycles: Synthesis, Structure, Properties and Application as Chiral Solvating Agents

    Czech Academy of Sciences Publication Activity Database

    Sheshenev, A. E.; Boltukhina, E. V.; Grishina, Anastasia; Císařová, I.; Lyapkalo, Ilya; Hii, K. K.

    2013-01-01

    Roč. 19, č. 25 (2013), s. 8136-8143 ISSN 0947-6539 Grant - others:7th European Community Framework Programme(XE) FP7-252247 Institutional support: RVO:61388963 Keywords : binding constants * chirality * enantioselectivity * NMR spectroscopy * phosphorus heterocycles * zwitterions Subject RIV: CC - Organic Chemistry Impact factor: 5.696, year: 2013

  17. Synthesis and Radiolabeling of Modified Peptides Attached to Heterocyclic Rings and Their Possible Medical Applications

    International Nuclear Information System (INIS)

    Shams El-Din, H.A.A.

    2012-01-01

    Keeping in mind the pharmacological potential of heterocyclic rings as well as the advantage of biodegradability and biocompatibility of amino acids/peptides, in this thesis we were prompted for the following: 1. Synthesis of novel dipeptide derivatives coupled with different heterocyclic rings (pyridine, 1,2,4-triazol-pyridine, 1,3,4-oxadiazolpyridine and tetrazol-pyridine rings). 2. Characterization of the synthesized compounds on the basis of their spectral data (IR, Mass and 1 H-NMR spectra). 3. Study their antimicrobial activity as one of their expected biological activities. 4. Study the radioiodination of some synthesized dipeptide derivatives. 5. Study the biodistribution of the radiolabeled compounds in normal mice as preliminary studies for the possibility of using them as agents for imaging and treatment.

  18. Application of heterocyclic aldehydes as components in Ugi–Smiles couplings

    Directory of Open Access Journals (Sweden)

    Katelynn M. Mason

    2016-09-01

    Full Text Available Efficient one-pot Ugi–Smiles couplings are reported for the use of furyl-substituted aldehyde components. In the presence of these heterocyclic aldehydes, reactions tolerated variations in amine components and led to either isolated N-arylamide Ugi–Smiles adducts or N-arylepoxyisoindolines, products of tandem Ugi–Smiles Diels–Alder cyclizations, in moderate yields. A thienyl-substituted aldehyde was also a competent component for Ugi–Smiles adduct formation.

  19. Bimacrocyclic concave N-heterocyclic carbenes (NHCs): synthesis, structure, and application in catalyses

    OpenAIRE

    Lüning , Ulrich; Winkelmann , Ole

    2009-01-01

    Abstract Imidazolinium moieties have been incorporated into bimacrocycles to generate precursors for concave N-heterocyclic carbenes (NHCs). Starting from 2-nitroresorcinol and alkenols, symmetric concave imidazolinium salts 1 were obtained. Bimacrocyclization was achieved via ring closing metathesis (RCM). In an analogous fashion, axially chiral concave imidazolinium salts 2 were obtained by using a naphthalene bridgehead devoid of local C2-symmetry. The concave NHCs derived from ...

  20. Application of micro-solid-phase extraction for the on-site extraction of heterocyclic aromatic amines in seawater.

    Science.gov (United States)

    Basheer, Chanbasha

    2018-04-01

    An efficient on-site extraction technique to determine carcinogenic heterocyclic aromatic amines in seawater has been reported. A micro-solid-phase extraction device placed inside a portable battery-operated pump was used for the on-site extraction of seawater samples. Before on-site applications, parameters that influence the extraction efficiency (extraction time, type of sorbent materials, suitable desorption solvent, desorption time, and sample volume) were investigated and optimized in the laboratory. The developed method was then used for the on-site sampling of heterocyclic aromatic amines determination in seawater samples close to distillation plant. Once the on-site extraction completed, the small extraction device with the analytes was brought back to the laboratory for analysis using high-performance liquid chromatography with fluorescence detection. Based on the optimized conditions, the calibration curves were linear over the concentration range of 0.05-20 μg/L with correlation coefficients up to 0.996. The limits of detection were 0.004-0.026 μg/L, and the reproducibility values were between 1.3 and 7.5%. To evaluate the extraction efficiency, a comparison was made with conventional solid-phase extraction and it was applied to various fortified real seawater samples. The average relative recoveries obtained from the spiked seawater samples varied in the range 79.9-95.2%. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Regioselective Aziridination of Silyl Allenes and Application for the Synthesis of New Heterocycles

    Science.gov (United States)

    Burke, Eileen Grace

    Rhodium catalyzed aziridination of homoallenic sulfamates has proven to be a successful first step in the synthesis of a diverse array of complex nitrogenated motifs. Previously, however, the resultant methyleneaziridine was limited to the exocyclic isomer. In this work, a reliable direction strategy for the formation of the endocyclic isomer was identified. Placement of a silicon group on the allene so that its C - Si bond is co-planar to the distal pi-bond allowed for stabilization of the developing positive charge during aziridination, and therefore selective activation to form the endocyclic methyleneaziridine. This strategy proved robust, and endocyclic methyleneaziridines were formed in high yields with exclusive formation of the desired isomer regardless of the substitution of the allene. With the endocyclic isomer now readily available, its reactivity could be explored. First, the endocyclic methyleneaziridine was applied to the synthesis of densely functionalized, nitrogen containing motifs. In comparison with their exocyclic counterparts, the endocyclic methyleneaziridines were found to have differing reactivity. The olefin could be epoxidized using meta-chloroperoxybenzoic acid (mCPBA), and the resulting spirocyclic intermediate rapidly rearranged to an azetidin-3-one. This synthesis of the highly substituted fourmembered heterocycle represented a novel approach to these motifs, and was found to be both flexible, and to selectively form a single diastereomer. Additional derivatization of these scaffolds gave a diverse array of complex products. Further use of the endocyclic methyleneaziridine focused not on the complexity of the product motif but rather on its utility. The remaining silyl group could be eliminated upon reaction with a fluoride source, triggering the formation of an alkyne and resultant opening of the aziridine. This strained heterocyclic alkyne and its synthesis represent a new addition to the field of strained alkyne synthesis. Uniquely

  2. Bicycle Safety in Action.

    Science.gov (United States)

    National Commission on Safety Education, Washington, DC.

    This material was designed to assist schools in teaching bicycle safety. As the population grows and competition for road space increases, it is more imperative than ever that we concentrate attention on the need for caution among pupil cyclists. The pamphlet: (1) discusses the role of bicycle safety in classroom instruction and in student…

  3. Bicycle Purchaser Training Workshop.

    Science.gov (United States)

    Schwarz, William

    A course was developed to provide data to buyers of new bicycles so they could make an informed decision about their purchases. The instructional systems design process (analysis, design, development, implementation, and evaluation) was used to analyze the need for a training course on buying and fitting a bicycle. Information was collected…

  4. A practical application of the geometrical theory on fibered manifolds to an autonomous bicycle motion in mechanical system with nonholonomic constraints

    Science.gov (United States)

    Haddout, Soufiane

    2018-01-01

    The equations of motion of a bicycle are highly nonlinear and rolling of wheels without slipping can only be expressed by nonholonomic constraint equations. A geometrical theory of general nonholonomic constrained systems on fibered manifolds and their jet prolongations, based on so-called Chetaev-type constraint forces, was proposed and developed in the last decade by O. Krupková (Rossi) in 1990's. Her approach is suitable for study of all kinds of mechanical systems-without restricting to Lagrangian, time-independent, or regular ones, and is applicable to arbitrary constraints (holonomic, semiholonomic, linear, nonlinear or general nonholonomic). The goal of this paper is to apply Krupková's geometric theory of nonholonomic mechanical systems to study a concrete problem in nonlinear nonholonomic dynamics, i.e., autonomous bicycle. The dynamical model is preserved in simulations in its original nonlinear form without any simplifying. The results of numerical solutions of constrained equations of motion, derived within the theory, are in good agreement with measurements and thus they open the possibility of direct application of the theory to practical situations.

  5. Do Online Bicycle Routing Portals Adequately Address Prevalent Safety Concerns?

    Directory of Open Access Journals (Sweden)

    Martin Loidl

    2018-03-01

    Full Text Available Safety concerns are among the most prevalent deterrents for bicycling. The provision of adequate bicycling infrastructure is considered as one of the most efficient means to increase cycling safety. However, limited public funding does not always allow agencies to implement cycling infrastructure improvements at the desirable level. Thus, bicycle trip planners can at least partly alleviate the lack of adequate infrastructure by recommending optimal routes in terms of safety. The presented study provides a systematic review of 35 bicycle routing applications and analyses to which degree they promote safe bicycling. The results show that most trip planners lack corresponding routing options and therefore do not sufficiently address safety concerns of bicyclists. Based on these findings, we developed recommendations on how to better address bicycling safety in routing portals. We suggest employing current communication technology and analysis to consider safety concerns more explicitly.

  6. Synthesis, characterization and applications of some novel mordent and heterocyclic disperse dyes on polyester and wool fibers

    Directory of Open Access Journals (Sweden)

    Hitendra Mangubhai Patel

    2012-10-01

    Full Text Available The novel mordent and disperse heterocyclic dyes were prepared by coupling of various diazo solution of aromatic amines with 1-[(2-butyl-2,3-dihydrobenzofuran-3-yl]-1-(4-hydroxyphenylmethanone. The resultant mordent and disperse heterocyclic dyes were characterized by elemental analyses, IR and 1H-NMR and 13C-NMR spectral studies. The UV-visible spectral data have also been discussed in terms of structural property relationship. The dyeing assessment of all the mordent and disperse heterocyclic dyes was evaluated on wool and polyester textile fibers. The results of antibacterial studies of chrome pretreated fabrics revealed that the toxicity of mordented dyes against Escherichia coli, Staphylococcus aureus, Salmonella typhi, Bacillus subtilis bacteria was fairly good.

  7. Cationic bis-N-heterocyclic carbene (NHC) ruthenium complex: Structure and application as latent catalyst in olefin metathesis

    KAUST Repository

    Rouen, Mathieu

    2014-09-11

    An unexpected cationic bis-N-heterocyclic carbene (NHC) benzylidene ether based ruthenium complex (2 a) was prepared through the double incorporation of an unsymmetrical unsaturated N-heterocyclic carbene (U2-NHC) ligand that bore an N-substituted cyclododecyl side chain. The isolation and full characterization (including X-ray diffraction studies) of key synthetic intermediates along with theoretical calculations allowed us to understand the mechanism of the overall cationization process. Finally, the newly developed complex 2 a displayed interesting latent behavior during ring-closing metathesis, which could be "switched on" under acidic conditions.

  8. Application of Finite Element Method to Determine the Performances of a Permanent Magnet Synchronous Motor for Driving a Bicycle

    Directory of Open Access Journals (Sweden)

    Nicolae Digă

    2014-09-01

    Full Text Available In this paper, the authors present a case study in which was analyzed by finite element method a permanent magnet synchronous motor for driving a bicycle using the analysis and simulation software ANSYS Electromagnetics Low Frequency of ANSYS Inc. Company. Modelling and simulation with ANSYS ® Maxwell 2D of electromagnetic field in the studied motor was conducted for different initial positions (internal angle rotor-stator configured (set δ1. It was identified the internal angle for which the performances of PMSM are very close to those obtained by computation.

  9. An Operator's Guide to Safe and Enjoyable Bicycling.

    Science.gov (United States)

    San Jose Dept. of Public Works, CA.

    Addressed to young persons and adults, this booklet delineates the duties and rights applicable to bicyclists as drivers of vehicles. The following topics are discussed: Rules of the road, defensive bicycling techniques, the bicycle as a machine, registration and theft prevention, walking the bike, bike routes, and recreational and group rides.…

  10. Failure modes of valve-regulated lead-acid batteries for electric bicycle applications in deep discharge

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Yonglang; Tang, Shengqun [College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350108 (China); Meng, Gang; Yang, Shijun [Hubei Camel Storage Battery Co. Ltd., Gucheng 441705 (China)

    2009-06-01

    The 36 or 48 V valve-regulated lead-acid (VRLA) battery packs have been widely applied to the power sources of electric bicycles or light electric scooters in China. The failure modes of the 12 V/10 Ah VRLA batteries have been studied by the cycle life test at C{sub 2} discharge rate and 100% depth of discharge (DOD). It indicates that the main cause of the battery failure in this cycle duty is the softening and shedding of positive active mass (PAM) rather than individual water loss, recombination efficiency or sulfation, etc. When the electrolyte saturation falls to a certain extent, the high oxygen recombination current leads to the depolarization of the negative plate and the shift of the positive plate to a higher potential. The violent oxygen evolution accelerates the softening of PAM and the end of cycle life. (author)

  11. An electrochemical procedure coupled with a Schiff base method; application to electroorganic synthesis of new nitrogen-containing heterocycles

    International Nuclear Information System (INIS)

    Dowlati, Bahram; Othman, Mohamed Rozali

    2013-01-01

    The synthesis of Nitrogen-containing heterocycles has been achieved using chemical and electrochemical methods, respectively. The direct chemical synthesis of nucleophiles proceeds through the Schiff base chemical reaction. This procedure offers an alternate reaction between dicarbonyl compounds and diamines leads to the formation of products. The results indicate that the Schiff base chemical method for synthesis of the product has successfully performed in excellent overall yield. In the electrochemical step, a series of Nitrogen-containing compounds were electrosynthesized. Various parameters such as the applied potential, pH of the electrolytic solution, cell configuration and also purification techniques, were carried out to optimize the yields of corresponding products. New Nitrogen-containing heterocycle derivatives were synthesized using an electrochemical procedure coupled with a Schiff base as a facile, efficient and practical method. The products have been characterized after purification by IR, 1 H NMR, 13 C NMR and ESI-MS 2

  12. Butchers and Bicycles

    DEFF Research Database (Denmark)

    Kahle, Lynn; Eriksen, Steen Mandsfelt

    2016-01-01

    Morten Wagener is a Danish design, and innovator who founded the cargo and personal transportation bicycle company, ”Butchers and Bicycles,”. He identified a business opportunity to improve the future of urban transport. His idea was that most of the trikes) on the market lacked good design......, maneuverability and styling. With his engineering and design background, Wagener set out to design a new trike; which would meet the needs of the target market, which his research identified as well- educated individuals who were very interested in aesthetics. Furthermore, Wagener was convinced that trikes were...... between order and delivery. From a marketing perspective, one of the differentiating factors of Morten’s product is the quality of the ride (compared to competing products) and so his marketing team coined the slogan “Built-to-Tilt” because even though it’s a trike it feels like riding a two...

  13. Synthesis of Heterocycles through a Ruthenium‐Catalyzed Tandem Ring‐Closing Metathesis/Isomerization/N‐Acyliminium Cyclization Sequence

    DEFF Research Database (Denmark)

    Ascic, Erhad; Jensen, Jakob Feldthusen; Nielsen, Thomas Eiland

    2011-01-01

    Tandem bicycle: In the title reaction double bonds created during ring-closing metathesis isomerize to generate reactive iminium intermediates that undergo intramolecular cyclization reactions with tethered heteroatom and carbon nucleophiles. In this way, a series of biologically interesting hete...... heterocyclic compounds can be made, including a known precursor for the total synthesis of the antiparasitic natural product harmicine....

  14. Microwave-Assisted Multicomponent Synthesis of Heterocycles

    NARCIS (Netherlands)

    Kruithof, A.; Ruijter, E.; Orru, R.V.A.

    2011-01-01

    Multicomponent reactions are valuable tools for the generation of diverse heterocycles. As in many fields or organic chemistry, microwave irradiation is rapidly replacing conventional heating methods in multicomponent chemistry. In this review, we present an overview of recent applications of the

  15. Bicycle traffic in urban areas

    Directory of Open Access Journals (Sweden)

    Anđelković Zorica

    2015-01-01

    Full Text Available Cycling is a term describing the use of bicycles, but also any mean of transport driven solely by human power. Development of bicycle traffic in urban areas involves construction of cycling infrastructure, adapting streets and other traffic infrastructure to a form suitable for cycling and other means of transport (individual motorized traffic, public transport, walking, ensuring the adequate budget and systematic planning and development of sustainable transport in cities. The paper presents basic settings and conditions as input elements to plan bicycle traffic in urban areas, as well as program- design conditions which lead the activities of planners and designers of urban roads in connection with cyclists.

  16. Free Use of Bicycles at CERN

    CERN Multimedia

    2000-01-01

    Imagine you have just arrived at CERN. You are from Russia or Japan and have no car but you do need to get around and do not like depending on public transport. What do you do? You go to the EP Service Point (Building 124) and meet Boris Cabaud to get a CERN bicycle. Use of the bicycle is free but you have to fill in an application form which needs to be signed by your Group or Division Secretary. Then the application is filled in, you are put on the waiting list and it might take you from one to four weeks to get your bike depending on the season. “Normally the bikes are only for Users in the EP division as they are paid for by the EP budget,” says Boris, “but some other divisions have made arrangements to cover the costs.” Boris takes care of 350 bicycles at present. Each bike can be lent for maximum one year. During the winter the bikes can be stored in building 301 as it is difficult to ride them in the snow. If a bike is broken or lost all costs will be billed to the group or team account of the bo...

  17. Synthesis and research of benzylamides of some isocyclic and heterocyclic acids as potential anticonvulsants.

    Science.gov (United States)

    Strupińska, Marzanna; Rostafińska-Suchar, Grazyna; Pirianowicz-Chaber, Elzbieta; Stables, James P; Jiang, Jeff; Paruszewski, Ryszard

    2013-01-01

    A series of benzylamides of isocyclic and heterocyclic acids was synthesized and tested in Anticonvulsant Screening Project (ASP) of Antiepileptic Drug Development Program (ADDP) of NIH. Near all synthesized derivatives of heterocyclic acids showed activity. All obtained derivatives of mono- and bicyclic isocyclic acids were inactive. The power of action of heterocyclic acids derivatives seems does not depend upon kind of heteroatom (N, O or S). One of the compounds (2-furoic acid benzylamide (4)) appeared most promising. It showed in minimal clonic seizure (6Hz) test (ASP) in rats after i. p. administration: MES ED50 = 36.5 mg/kg, TOX TD50 = 269.75 mg/kg, and PI = 7.39.

  18. Application of chitosan and its N-heterocyclic derivatives for preconcentration of noble metal ions and their determination using atomic absorption spectrometry.

    Science.gov (United States)

    Azarova, Yu A; Pestov, A V; Ustinov, A Yu; Bratskaya, S Yu

    2015-12-10

    Chitosan and its N-heterocyclic derivatives N-2-(2-pyridyl)ethylchitosan (2-PEC), N-2-(4-pyridyl) ethylchitosan (4-PEC), and N-(5-methyl-4-imidazolyl) methylchitosan (IMC) have been applied in group preconcentration of gold, platinum, and palladium for subsequent determination by atomic absorption spectroscopy (AAS) in solutions with high background concentrations of iron and sodium ions. It has been shown that the sorption mechanism, which was elucidated by XPS, significantly influences the sorption capacity of materials, the efficiency of metal ions elution after preconcentration, and, as a result, the accuracy of metal determination by AAS. We have shown that native chitosan was not suitable for preconcentration of Au(III), if the elution step was used as a part of the analysis scheme. The group preconcentration of Au(III), Pd(II), and Pt(IV) with subsequent quantitative elution using 0.1M HCl/1M thiourea solution was possible only on IMC and 4-PEC. Application of IMC for analysis of the national standard quartz ore sample proved that gold could be accurately determined after preconcentration/elution with the recovery above 80%. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Statewide analysis of bicycle crashes : [project summary].

    Science.gov (United States)

    2017-06-01

    An extensive literature review was conducted to locate existing studies in four areas: (1) risk factors that affect the frequency and severity of bicycle crashes; (2) bicycle crash causes, patterns, and contributing factors; (3) network screening met...

  20. An integrated approach to bicycle safety.

    NARCIS (Netherlands)

    Wittink, R.D.

    1997-01-01

    The advantages of cycling are outlined, as well as the conditions under which use of the bicycle and the safety of cycling can he promoted. Bicycles are an attractive product. The potential to use a bicycle for trips shorter than 5 km is high and it's use can also be substantial for longer

  1. A review on bis-hydrazonoyl halides: Recent advances in their synthesis and their diverse synthetic applications leading to bis-heterocycles of biological interest

    Directory of Open Access Journals (Sweden)

    Ahmad Sami Shawali

    2016-11-01

    Full Text Available This review covers a summary of the literature data published on the chemistry of bis-hydrazonoyl halides over the last four decades. The biological activities of some of the bis-heterocyclic compounds obtained from these bis-hydrazonoyl halides are also reviewed and discussed.

  2. EP BICYCLE POOL - VIGNETTES 2002

    CERN Multimedia

    EP-SMI Help Desk

    2002-01-01

    The vignettes (insurance certificates) for 2002 become obligatory from 1 June. If you have a bicycle from the EP Pool, please bring it to the EP-SMI Help Desk (Building 124) on any working day up to 31 May between 8h.30 - 12h.00 or 13h.30 - 17h.30. EP-SMI Help Desk

  3. Bicycle Safety: Sport Education Style

    Science.gov (United States)

    Sinelnikov, Oleg A.; Hastie, Peter A.; Cole, Amy; Schneulle, Deanna

    2005-01-01

    Although the benefits of regular physical activity are well-documented and very well known, Americans are still becoming more sedentary and obese. As some experts envision the potential of nonmotorized transport in the future, especially in urban settings, it is not surprising that diverse groups view walking and bicycling as a solution to an…

  4. Applications of ortho-phenylisonitrile and ortho-N-Boc aniline for the two-step preparation of novel bis-heterocyclic chemotypes.

    Science.gov (United States)

    Xu, Zhigang; Shaw, Arthur Y; Nichol, Gary S; Cappelli, Alexandra P; Hulme, Christopher

    2012-08-01

    Concise routes to five pharmacologically relevant bis-heterocyclic scaffolds are described. Significant molecular complexity is generated in a mere two synthetic operations enabling access to each scaffold. Routes are often improved by microwave irradiation and all utilize isocyanide-based multi-component reaction methods to incorporate the required diversity elements. Common reagents in all initial condensation reactions include 2-(N-Boc-amino)-phenyl-isocyanide 1, mono-Boc-phenylenediamine 2 and ethyl glyoxalate 3.

  5. Bicycle urbanism as competitive advantage in the neoliberal age

    DEFF Research Database (Denmark)

    Ibsen, Mikkel Elkær; Olesen, Kristian

    2018-01-01

    In the light of the emergent ‘bicycle renaissance’ in the US, this paper analyses the rationale basis of bicycle role model, Portland’s promotion of bicycling. By conceptualizing bicycle promotion as a ‘travelling idea’, the paper discusses the key rationales and discourses structuring how bicycl...

  6. Road accidents involving bicycles: configurations and injuries.

    Science.gov (United States)

    Orsi, Chiara; Montomoli, Cristina; Otte, Dietmar; Morandi, Anna

    2017-12-01

    This study analyzed the most common types of accident involving bicycles and compared the frequency of injuries. The data source was the database of German In-Depth Accident Study (GIDAS). Cases consist of bicycles and their riders involved in accidents between 2000 and 2010. In most collisions, the bicycle impacted with a car. The percentage of injured bicyclists was higher in collisions with a heavy vehicle and decreased when the bicycle impacted with lighter vehicles. A high percentage of injured bicyclists in single accidents was observed; the most severe injury was more frequently to head and extremities. Accidents involving a car and a bicycle with the right of way in a bicycle path represented about 20% of involved and injured bicyclists. The ten most frequent configurations represented about 60% of involved and injured bicyclists. These results contribute to understand the dangerous scenarios for bicyclists and to suggest preventive actions.

  7. Design and analysis of sustainable paper bicycle

    Science.gov (United States)

    Roni Sahroni, Taufik; Nasution, Januar

    2017-12-01

    This paper presents the design of sustainable paper bicycle which describes the stage by stage in the production of paper bicycle. The objective of this project is to design a sustainable paper bicycles to be used for children under five years old. The design analysis emphasizes in screening method to ensure the design fulfil the safety purposes. The evaluation concept is presented in designing a sustainable paper bicycle to determine highest rating. Project methodology is proposed for developing a sustainable paper bicycle. Design analysis of pedal, front and rear wheel, seat, and handle were presented using AutoCAD software. The design optimization was performed to fulfil the safety factors by modifying the material size and dimension. Based on the design analysis results, it is found that the optimization results met the factor safety. As a result, a sustainable paper bicycle was proposed for children under five years old.

  8. Identification of the mechanical properties of bicycle tyres for modelling of bicycle dynamics

    Science.gov (United States)

    Doria, Alberto; Tognazzo, Mauro; Cusimano, Gianmaria; Bulsink, Vera; Cooke, Adrian; Koopman, Bart

    2013-03-01

    Advanced simulation of the stability and handling properties of bicycles requires detailed road-tyre contact models. In order to develop these models, in this study, four bicycle tyres are tested by means of a rotating disc machine with the aim of measuring the components of tyre forces and torques that influence the safety and handling of bicycles. The effect of inflation pressure and tyre load is analysed. The measured properties of bicycle tyres are compared with those of motorcycle tyres.

  9. Bamboo Bicycle – Past or Future?

    Directory of Open Access Journals (Sweden)

    Suzana Jakovljević

    2016-01-01

    Full Text Available In this article the experiment was carried out to establish tensile strength values of two different bamboo species, which are obtained by the static tensile test. The tensile strength results of two tested species Tonkin Cane and Ku Zhu bamboo are presented and compared with traditional materials used for bicycle frame to determine their suitability for designing a frame. Physiology and other properties of bamboo were elaborated as well. The purpose of this study was to gain more knowledge on bamboo and prove his suitability in use as an alternative for ecologically unacceptable materials. Therefore, application of the natural materials is essential for the sustainable development. The fact that they have unlimited resources the use of bamboo has great potential and this article explains why.

  10. Alkoxy(alkyl)silylalkyl derivatives of nitrogen-containing heterocycles

    International Nuclear Information System (INIS)

    Trofimova, Ol'ga M; Voronkov, Mikhail G; Chernov, Nikolai F

    1999-01-01

    The published data on the synthesis, properties and transformations of alkoxy(alkyl)silylalkyl derivatives of nitrogen-containing heterocycles of the general formula Het(CH 2 ) n SiX 3 are surveyed and systematised. Data on the biological activities and applications of these compounds are presented. The bibliography includes 255 references.

  11. Application of Chan-Lam cross coupling for the synthesis of N-heterocyclic carbene precursors bearing strong electron donating or withdrawing groups

    Science.gov (United States)

    Huang, Liliang; He, Chengxiang; Sun, Zhihua

    2015-07-01

    Chan-Lam cross coupling allowed efficient synthesis of N,N’-disubstituted ortho-phenylene diamines bearing strong electron donating or withdrawing groups, such as nitro or methoxy groups, with moderate to high yields. These diamines can then be turned into N-heterocyclic carbene precursors after condensation with trimethyl orthoformate. The same strategy can also be utilized for the synthesis of N-monosubstituted aniline derivatives containing a functionalized ortho-aminomethyl group as intermediates for chiral 6-membered ring carbene precursors.

  12. Evaluation electric bicycles; Evaluation velos electriques

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-10-01

    Leovelo service is the first measure in favor of the bicycle to control the air pollution and to conserve energy. It provides in the city of Clermont-Ferrand (France) a service of bicycle hiring. This document evaluates the project after two years of operating. It provides a technical evaluation (maintenance, equipment, financing) and also the socio-economic impacts. (A.L.B.)

  13. A study on electric bicycle energy efficiency

    Directory of Open Access Journals (Sweden)

    Ivan EVTIMOV

    2015-09-01

    Full Text Available The paper presents a construction of an experimental electric bicycle for evaluation of the energy efficiency. The bicycle is equipped with onboard computer which can store the information about motion and energy consumption. The result concerning power, energy consumption, recharging during brake process, etc. are given. Energy consumption for 3 typical city routes is studied.

  14. SOFIE, a bicycle that supports older cyclists?

    NARCIS (Netherlands)

    Dubbeldam, R.; Baten, C.; Buurke, J. H.; Rietman, J. S.

    2017-01-01

    Older cyclists remain at high risk of sustaining an injury after a fall with their bicycle. A growing awareness for the need and possibilities to support safety of older cyclists has been leading to bicycle design ideas. However, the effectiveness and acceptance of such designs has not been studied

  15. The environmental benefits of bicycling and walking.

    Science.gov (United States)

    1993-01-01

    Bicycling and walking are the two major non-fuel-consuming, non-polluting : forms of transportation in the United States. Millions of Americans ride : bicycles and/or walk for a wide variety of purposes --- commuting to work, as : part of their job, ...

  16. Adsorption Characteristics of DNA Nucleobases, Aromatic Amino Acids and Heterocyclic Molecules on Silicene and Germanene Monolayers

    KAUST Repository

    Hussain, Tanveer; Vovusha, Hakkim; Kaewmaraya, Thanayut; Amornkitbamrung, Vittaya; Ahuja, Rajeev

    2017-01-01

    Binding of DNA/RNA nucleobases, aromatic amino acids and heterocyclic molecules on two-dimensional silicene and germanene sheets have been investigated for the application of sensing of biomolecules using first principle density functional theory

  17. Azomesogens with a heterocyclic moiety

    Indian Academy of Sciences (India)

    Unknown

    Azomesogens with a heterocyclic moiety. †. JAYRANG S DAVE and MEERA MENON*. Department of Applied Chemistry, Faculty of Technology and Engineering, MS University of Baroda,. Baroda 390 001, India. Abstract. Azobenzene derivatives were among the first ten liquid crystalline compounds. But there have been.

  18. Revealed Preference Methods for Studying Bicycle Route Choice—A Systematic Review

    Directory of Open Access Journals (Sweden)

    Ray Pritchard

    2018-03-01

    Full Text Available One fundamental aspect of promoting utilitarian bicycle use involves making modifications to the built environment to improve the safety, efficiency and enjoyability of cycling. Revealed preference data on bicycle route choice can assist greatly in understanding the actual behaviour of a highly heterogeneous group of users, which in turn assists the prioritisation of infrastructure or other built environment initiatives. This systematic review seeks to compare the relative strengths and weaknesses of the empirical approaches for evaluating whole journey route choices of bicyclists. Two electronic databases were systematically searched for a selection of keywords pertaining to bicycle and route choice. In total seven families of methods are identified: GPS devices, smartphone applications, crowdsourcing, participant-recalled routes, accompanied journeys, egocentric cameras and virtual reality. The study illustrates a trade-off in the quality of data obtainable and the average number of participants. Future additional methods could include dockless bikeshare, multiple camera solutions using computer vision and immersive bicycle simulator environments.

  19. Electric bicycles in The Netherlands: Current developments and future possibilities

    NARCIS (Netherlands)

    Rooijen, T. van

    2010-01-01

    Developments with electric bicycles in the Netherlands are progressing rapidly. The number of electric bicycles sold is rises every year. Cycling is a very popular mode of transport in The Netherlands. In 2008 more than one million bicycles were sold. At the moment one out of ten bicycles sold is

  20. Synthesis of heterocyclic compounds through palladium-catalyzed C-H cyclization processes.

    Science.gov (United States)

    Inamoto, Kiyofumi

    2013-01-01

    Herein, we describe our development of synthetic methods for heterocyclic compounds based on the palladium-catalyzed carbon-hydrogen bond (C-H) functionalization/intramolecular carbon-heteroatom (nitrogen or sulfur) bond formation process. By this C-H cyclization method, we efficiently prepared various N-heterocycles, including indazoles, indoles, and 2-quinolinones, as well as S-heterocycles such as benzothiazoles and benzo[b]thiophenes. Yields are typically good to high and good functional-group tolerance is observed for each process, thereby indicating that the method provides a novel, highly applicable synthetic route to the abovementioned biologically important heterocyclic frameworks. As an application of this approach, an auto-tandem-type, one-pot process involving the oxidative Heck reaction and subsequent C-H cyclization using cinnamamides and arylboronic acids as starting materials in the presence of a palladium catalyst was also developed for the rapid construction of the 2-quinolinone nucleus.

  1. Low-stress bicycling and network connectivity.

    Science.gov (United States)

    2012-05-01

    For a bicycling network to attract the widest possible segment of the population, its most fundamental attribute should be low-stress connectivity, that is, providing routes between peoples origins and destinations that do not require cyclists to ...

  2. 36 CFR 1004.30 - Bicycles.

    Science.gov (United States)

    2010-07-01

    ... parking area to bicycle use pursuant to the criteria and procedures of §§ 1001.5 and 1001.7 of this... consistent with the protection of natural, scenic and aesthetic values, safety considerations and management...

  3. On-road Bicycle Pavement Markings

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — A mile by mile breakdown of the on-street bicycle pavement markings installed within the City of Pittsburgh. These include bike lanes, shared lane markings...

  4. Bicycle-bus conflict area study.

    Science.gov (United States)

    2009-11-01

    Increasing bicycle use and bus ridership are both desirable policy goals : from a sustainability standpoint, but on city streets these two modes of : transport are often in conflict. While occupying opposite ends of the size : and weight spectrum, th...

  5. Bicycles, transportation sustainability, and quality of life.

    Science.gov (United States)

    2014-01-01

    The research presented in this report focuses on the exploration of a variety of objective and subjective quality of life indicators and approaches for bicycle transportation using a mixed methods approach. The authors have created a conceptual frame...

  6. Heterociclos 1,2,3-triazólicos: histórico, métodos de preparação, aplicações e atividades farmacológicas 1,2,3-triazolic heterocycles: history, preparations, applications and pharmacological activities

    Directory of Open Access Journals (Sweden)

    Júlio O. F. Melo

    2006-06-01

    Full Text Available The 1,2,3-triazole, known since the end of 19th century, is a very widely used heterocyclic system present in many synthetic substances and commercial pharmaceutical compounds. In fact, 1,2,3-triazoles show several applications in many areas especially as medicines against many diseases like cancer, AIDS, Parkinson and Alzheimer. Nowadays there is a large variety of known methods to obtain these heterocyclic compounds comprising mainly three synthetic routes. Nevertheless, there is no article that gives an objective overview of the synthetic methods for obtaining these kinds of azoheterocycles. This paper presents a brief history of this class of compounds, and a synthetic discussion concerning the main synthetic methods for its preparation, such as cyclization through hydrazones, concerted cycloadditon [2+3] and pseudopericyclic cyclization - and some others of restricted application, but also important. Finally, this paper also provides a brief overview on pharmacological applications of some 1,2,3-triazoles.

  7. Electric motor assisted bicycle as an aerobic exercise machine.

    Science.gov (United States)

    Nagata, T; Okada, S; Makikawa, M

    2012-01-01

    The goal of this study is to maintain a continuous level of exercise intensity around the aerobic threshold (AT) during riding on an electric motor assisted bicycle using a new control system of electrical motor assistance which uses the efficient pedaling rate of popular bicycles. Five male subjects participated in the experiment, and the oxygen uptake was measured during cycling exercise using this new pedaling rate control system of electrical motor assistance, which could maintain the pedaling rate within a specific range, similar to that in previous type of electrically assisted bicycles. Results showed that this new pedaling rate control system at 65 rpm ensured continuous aerobic exercise intensity around the AT in two subjects, and this intensity level was higher than that observed in previous type. However, certain subjects were unable to maintain the expected exercise intensity because of their particular cycling preferences such as the pedaling rate. It is necessary to adjust the specific pedaling rate range of the electrical motor assist control according to the preferred pedaling rate, so that this system becomes applicable to anyone who want continuous aerobic exercise.

  8. Assembly of Four Diverse Heterocyclic Libraries Enabled by Prins Cyclization, Au-Catalyzed Enyne Cycloisomerization, and Automated Amide Synthesis

    Science.gov (United States)

    Cui, Jiayue; Chai, David I.; Miller, Christopher; Hao, Jason; Thomas, Christopher; Wang, JingQi; Scheidt, Karl A.; Kozmin, Sergey A.

    2013-01-01

    We describe a unified synthetic strategy for efficient assembly of four new heterocyclic libraries. The synthesis began by creating a range of structurally diverse pyrrolidinones or piperidinones. Such compounds were obtained in a simple one-flask operation starting with readily available amines, ketoesters, and unsaturated anhydrides. The use of tetrahydropyran-containing ketoesters, which were rapidly assembled by our Prins cyclization protocol, enabled efficient fusion of pyran and piperidinone cores. A newly developed Au(I)-catalyzed cycloisomerization of alkyne-containing enamides further expanded heterocyclic diversity by providing rapid entry into a wide range of bicyclic and tricyclic dienamides. The final stage of the process entailed diversification of each of the initially produced carboxylic acids using a fully automated platform for amide synthesis, which delivered 1872 compounds in high diastereomeric and chemical purity. PMID:22860634

  9. Aerobic Pd-Catalyzed sp3 C–H Olefination: A Route to Both N-Heterocyclic Scaffolds and Alkenes

    Science.gov (United States)

    Stowers, Kara J.; Fortner, Kevin C.

    2011-01-01

    This communication describes a new method for the Pd/polyoxometalate-catalyzed aerobic olefination of unactivated sp3 C–H bonds. Nitrogen heterocycles serve as directing groups, and air is used as the terminal oxidant. The products undergo reversible intramolecular Michael addition, which protects the mono-alkenylated product from over-functionalization. Hydrogenation of the Michael adducts provides access to bicyclic nitrogen-containing scaffolds that are prevalent in alkaloid natural products. Additionally, the cationic Michael adducts undergo facile elimination to release α,β-unsaturated olefins, which can be elaborated in numerous C–C and C–heteroatom bond-forming reactions. PMID:21476513

  10. Heterocyclic Scaffolds: Centrality in Anticancer Drug Development.

    Science.gov (United States)

    Ali, Imran; Lone, Mohammad Nadeem; Al-Othman, Zeid A; Al-Warthan, Abdulrahman; Sanagi, Mohd Marsin

    2015-01-01

    Cancer has been cursed for human beings for long time. Millions people lost their lives due to cancer. Despite of the several anticancer drugs available, cancer cannot be cured; especially at the late stages without showing any side effect. Heterocyclic compounds exhibit exciting medicinal properties including anticancer. Some market selling heterocyclic anticancer drugs include 5-flourouracil, methortrexate, doxorubicin, daunorubicin, etc. Besides, some natural products such as vinblastine and vincristine are also used as anticancer drugs. Overall, heterocyclic moeities have always been core parts in the expansion of anticancer drugs. This article describes the importance of heterocyclic nuclei in the development of anticancer drugs. Besides, the attempts have been made to discuss both naturally occurring and synthetic heterocyclic compounds as anticancer agents. In addition, some market selling anticancer heterocyclic compounds have been described. Moreover, the efforts have been made to discuss the mechanisms of actions and recent advances in heterocyclic compounds as anticancer agents. The current challenges and future prospectives of heterocyclic compounds have also been discussed. Finally, the suggestions for syntheses of effective, selective, fast and human friendly anticancer agents are discussed into the different sections.

  11. Electronic bond tuning with heterocyclic carbenes

    KAUST Repository

    Falivene, Laura

    2013-01-01

    We discuss the impact of the nature of the heterocyclic carbene ring, when used as a complex forming ligand, on the relative stability of key intermediates in three typical Ru, Pd and Au promoted reactions. Results show that P-heterocyclic carbenes have a propensity to increase the bonding of the labile ligand and of the substrate in Ru-promoted olefin metathesis, whereas negligible impact is expected on the stability of the ruthenacycle intermediate. In the case of Pd cross-coupling reactions, dissociation of a P-heterocyclic carbene is easier than dissociation of the N-heterocyclic analogue. In the case of the Au-OH synthon, the Au-OH bond is weakened with the P-heterocyclic carbene ligands. A detailed energy decomposition analysis is performed to rationalize these results. © 2013 The Royal Society of Chemistry.

  12. Bicycling to school improves the cardiometabolic risk factor profile

    DEFF Research Database (Denmark)

    Ostergaard, Lars; Børrestad, Line A B; Tarp, Jakob

    2012-01-01

    To investigate whether bicycling to school improves cardiometabolic risk factor profile and cardiorespiratory fitness among children.......To investigate whether bicycling to school improves cardiometabolic risk factor profile and cardiorespiratory fitness among children....

  13. Using crowdsourcing to prioritize bicycle network improvements : final report.

    Science.gov (United States)

    2016-04-01

    Effort to improve the bicycle route network using crowdsourced data is a powerful means : of incorporating citizens in infrastructure improvement decisions, which will improve : livability by maximizing the benefit of the bicycle infrastructure fundi...

  14. Methods to assess the stability of a bicycle rider system

    NARCIS (Netherlands)

    Cooke, A.G.; Bulsink, Vera Elisabeth; Beusenberg, Mark; Dubbeldam, Rosemary; Bonnema, Gerrit Maarten; Poelman, Wim; Koopman, Hubertus F.J.M.

    2012-01-01

    The SOFIE (Intelligent Assisted Bicycles) project wishes to create performance and design guidelines for mechatronic appliances which improve the stability of electric bicycles, so-called intelligent stability assist devices (IAD). To achieve this goal, a stability hypothesis, an advanced

  15. Successful Swiss solar bicycles in Australia

    International Nuclear Information System (INIS)

    Hansen, K.

    2000-01-01

    The article takes a look at the Swiss 'Spirit of Bike' team's success in the 'Power Challenge' race across Australia using solar-bicycles based on commercially available models. Apart from the sporting aspects of race, technical details on the cycles and their supply of solar power are given. Also, the history behind the success of the team is presented and the monitoring of man (and woman) and machine during the race is described. The article also discusses the electric bicycles that are commercially available and the potential of these energy-efficient vehicles in Switzerland

  16. Low-stress bicycling and network connectivity : [research brief].

    Science.gov (United States)

    2012-05-01

    In one sense, a citys or regions bicycling network includes all of its roads and paths on which bicycling is permitted. However, some streets provide such a poor level of safety and comfort for bicycling that the majority of the population cons...

  17. Investigation of Bicycle Travel Time Estimation Using Bluetooth Sensors for Low Sampling Rates

    Directory of Open Access Journals (Sweden)

    Zhenyu Mei

    2014-10-01

    Full Text Available Filtering the data for bicycle travel time using Bluetooth sensors is crucial to the estimation of link travel times on a corridor. The current paper describes an adaptive filtering algorithm for estimating bicycle travel times using Bluetooth data, with consideration of low sampling rates. The data for bicycle travel time using Bluetooth sensors has two characteristics. First, the bicycle flow contains stable and unstable conditions. Second, the collected data have low sampling rates (less than 1%. To avoid erroneous inference, filters are introduced to “purify” multiple time series. The valid data are identified within a dynamically varying validity window with the use of a robust data-filtering procedure. The size of the validity window varies based on the number of preceding sampling intervals without a Bluetooth record. Applications of the proposed algorithm to the dataset from Genshan East Road and Moganshan Road in Hangzhou demonstrate its ability to track typical variations in bicycle travel time efficiently, while suppressing high frequency noise signals.

  18. What do we know about bicycle helmets?

    NARCIS (Netherlands)

    Bogerd, C.P. Halldin, P. Houtenbos, M. Otte, D. Rossi, R.M. Walker, L. Willinger, R. & Shinar, D.

    2012-01-01

    Cycling is an excellent sustainable alternative to driving for many journeys. But cyclists have fewer safety options than car-users, with a helmet being the main safety device that is available. However, there are indications that increasing bicycle helmet usage through legislation causes

  19. Hydraulic brake-system for a bicycle

    NARCIS (Netherlands)

    Van Frankenhuyzen, J.

    2007-01-01

    The invention relates to a hydraulic brake system for a bicycle which may or may not be provided with an auxiliary motor, comprising a brake disc and brake claws cooperating with the brake disc, as well as fluid-containing channels (4,6) that extend between an operating organ (1) and the brake

  20. 36 CFR 4.30 - Bicycles.

    Science.gov (United States)

    2010-07-01

    ... road or parking area to bicycle use pursuant to the criteria and procedures of §§ 1.5 and 1.7 of this... consistent with the protection of a park area's natural, scenic and aesthetic values, safety considerations...

  1. The Synthesis of cis- and trans-Fused Bicyclic Sugar Amino Acids

    NARCIS (Netherlands)

    Risseeuw, Martijn D.P.; Grotenbreg, Gijsbert M.; Witte, Martin D.; Tuin, Adriaan W.; Leeuwenburgh, Michiel A.; Marel, Gijsbert A. van der; Overkleeft, Herman S.; Overhand, Mark

    2006-01-01

    Four isomeric bicyclic sugar amino acids (SAAs) were prepared from an α-acetylenic-C-glucoside by employing a Petasis olefination and a ring-closing metathesis (RCM) as key steps. The applicability of the resulting SAAs in solid-phase peptide synthesis was demonstrated by the synthesis of a

  2. Heterocyclic Anticancer Compounds: Recent Advances and the Paradigm Shift towards the Use of Nanomedicine's Tool Box.

    Science.gov (United States)

    Martins, Pedro; Jesus, João; Santos, Sofia; Raposo, Luis R; Roma-Rodrigues, Catarina; Baptista, Pedro Viana; Fernandes, Alexandra R

    2015-09-16

    The majority of heterocycle compounds and typically common heterocycle fragments present in most pharmaceuticals currently marketed, alongside with their intrinsic versatility and unique physicochemical properties, have poised them as true cornerstones of medicinal chemistry. Apart from the already marketed drugs, there are many other being investigated for their promising activity against several malignancies. In particular, anticancer research has been capitalizing on the intrinsic versatility and dynamic core scaffold of these compounds. Nevertheless, as for any other promising anticancer drugs, heterocyclic compounds do not come without shortcomings. In this review, we provide for a concise overview of heterocyclic active compounds and families and their main applications in medicine. We shall focus on those suitable for cancer therapy while simultaneously addressing main biochemical modes of action, biological targets, structure-activity relationships as well as intrinsic limitation issues in the use of these compounds. Finally, considering the advent of nanotechnology for effective selective targeting of drugs, we shall discuss fundamental aspects and considerations on nanovectorization of such compounds that may improve pharmacokinetic/pharmacodynamic properties of heterocycles.

  3. Allene functionalization via bicyclic methylene aziridines.

    Science.gov (United States)

    Boralsky, Luke A; Marston, Dagmara; Grigg, R David; Hershberger, John C; Schomaker, Jennifer M

    2011-04-15

    The oxidative functionalization of olefins is a common method for the formation of vicinal carbon-heteroatom bonds. However, oxidative methods to transform allenes into synthetic motifs containing three contiguous carbon-heteroatom bonds are much less developed. This paper describes the use of bicyclic methylene aziridines (MAs), prepared via intramolecular allene aziridination, as scaffolds for functionalization of all three allene carbons. © 2011 American Chemical Society

  4. Business Process Reengineering within the bicycle industry

    OpenAIRE

    Bartolomé Rodriguez, David

    2010-01-01

    Bicycle leader brands have shift production overseas to reduce the cost of labor and to implement new technologies at lower cost. Bike manufacturer both in Asia and Europe employ a traditional way of production  based on economics of scale that aims cost per unit reduction. Where MRP systems and forecasting are part of their day basis operations. This traditional way of operation offers room for innovation that must be seen as a business opportunity. Thus, alternative management approaches ca...

  5. Heterocyclic anions of astrobiological interest

    International Nuclear Information System (INIS)

    Cole, Callie A.; Demarais, Nicholas J.; Bierbaum, Veronica M.; Yang, Zhibo; Snow, Theodore P.

    2013-01-01

    As more complex organic molecules are detected in the interstellar medium, the importance of heterocyclic molecules to astrobiology and the origin of life has become evident. 2-Aminothiazole and 2-aminooxazole have recently been suggested as important nucleotide precursors, highlighting azoles as potential prebiotic molecules. This study explores the gas-phase chemistry of three deprotonated azoles: oxazole, thiazole, and isothiazole. For the first time, their gas-phase acidities are experimentally determined with bracketing and H/D exchange techniques, and their reactivity is characterized with several detected interstellar neutral molecules (N 2 O, O 2 , CO, OCS, CO 2 , and SO 2 ) and other reactive species (CS 2 , CH 3 Cl, (CH 3 ) 3 CCl, and (CH 3 ) 3 CBr). Rate constants and branching fractions for these reactions are experimentally measured using a modified commercial ion trap mass spectrometer whose kinetic data are in good accord with those of a flowing afterglow apparatus reported here. Last, we have examined the fragmentation patterns of these deprotonated azoles to elucidate their destruction mechanisms in high-energy environments. All experimental data are supported and complemented by electronic structure calculations at the B3LYP/6-311++G(d,p) and MP2(full)/aug-cc-pVDZ levels of theory.

  6. Heterocyclic anions of astrobiological interest

    Energy Technology Data Exchange (ETDEWEB)

    Cole, Callie A.; Demarais, Nicholas J.; Bierbaum, Veronica M. [Department of Chemistry and Biochemistry, 215 UCB, University of Colorado, Boulder, CO 80309 (United States); Yang, Zhibo [Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73019 (United States); Snow, Theodore P., E-mail: Callie.Cole@colorado.edu, E-mail: Nicholas.Demarais@colorado.edu, E-mail: Veronica.Bierbaum@colorado.edu, E-mail: Zhibo.Yang@ou.edu, E-mail: Theodore.Snow@colorado.edu [Department of Astrophysical and Planetary Sciences, 391 UCB, University of Colorado, Boulder, CO 80309 (United States)

    2013-12-20

    As more complex organic molecules are detected in the interstellar medium, the importance of heterocyclic molecules to astrobiology and the origin of life has become evident. 2-Aminothiazole and 2-aminooxazole have recently been suggested as important nucleotide precursors, highlighting azoles as potential prebiotic molecules. This study explores the gas-phase chemistry of three deprotonated azoles: oxazole, thiazole, and isothiazole. For the first time, their gas-phase acidities are experimentally determined with bracketing and H/D exchange techniques, and their reactivity is characterized with several detected interstellar neutral molecules (N{sub 2}O, O{sub 2}, CO, OCS, CO{sub 2}, and SO{sub 2}) and other reactive species (CS{sub 2}, CH{sub 3}Cl, (CH{sub 3}){sub 3}CCl, and (CH{sub 3}){sub 3}CBr). Rate constants and branching fractions for these reactions are experimentally measured using a modified commercial ion trap mass spectrometer whose kinetic data are in good accord with those of a flowing afterglow apparatus reported here. Last, we have examined the fragmentation patterns of these deprotonated azoles to elucidate their destruction mechanisms in high-energy environments. All experimental data are supported and complemented by electronic structure calculations at the B3LYP/6-311++G(d,p) and MP2(full)/aug-cc-pVDZ levels of theory.

  7. Derisking the Cu-Mediated 18F-Fluorination of Heterocyclic Positron Emission Tomography Radioligands.

    Science.gov (United States)

    Taylor, Nicholas J; Emer, Enrico; Preshlock, Sean; Schedler, Michael; Tredwell, Matthew; Verhoog, Stefan; Mercier, Joel; Genicot, Christophe; Gouverneur, Véronique

    2017-06-21

    Molecules labeled with fluorine-18 ( 18 F) are used in positron emission tomography to visualize, characterize and measure biological processes in the body. Despite recent advances in the incorporation of 18 F onto arenes, the development of general and efficient approaches to label radioligands necessary for drug discovery programs remains a significant task. This full account describes a derisking approach toward the radiosynthesis of heterocyclic positron emission tomography (PET) radioligands using the copper-mediated 18 F-fluorination of aryl boron reagents with 18 F-fluoride as a model reaction. This approach is based on a study examining how the presence of heterocycles commonly used in drug development affects the efficiency of 18 F-fluorination for a representative aryl boron reagent, and on the labeling of more than 50 (hetero)aryl boronic esters. This set of data allows for the application of this derisking strategy to the successful radiosynthesis of seven structurally complex pharmaceutically relevant heterocycle-containing molecules.

  8. Solid-phase synthesis of complex and pharmacologically interesting heterocycles

    DEFF Research Database (Denmark)

    Nielsen, Thomas Eiland

    2009-01-01

    Efficient routes for the creation of heterocycles continue to be one of the primary goals for solid-phase synthesis. Recent advances in this field rely most notably on transition-metal-catalysis and N-acyliminium chemistry to mediate a range of cyclization processes for the generation of compounds...... with significant structural complexity and diversity. This review describes some of the most systematic solid-phase approaches that are potentially suited for pharmaceutical applications, that is, the methods described are useful for the synthesis of compound collections, and exhibit tunable stereochemistry...

  9. Combinatorial Libraries of Bis-Heterocyclic Compounds with Skeletal Diversity

    Science.gov (United States)

    Soural, Miroslav; Bouillon, Isabelle; Krchňák, Viktor

    2009-01-01

    Combinatorial solid-phase synthesis of bis-heterocyclic compounds, characterized by the presence of two heterocyclic cores connected by a spacer of variable length/structure, provided structurally heterogeneous libraries with skeletal diversity. Both heterocyclic rings were assembled on resin in a combinatorial fashion. PMID:18811208

  10. Combinatorial Libraries of Bis-Heterocyclic Compounds with Skeletal Diversity

    OpenAIRE

    Soural, Miroslav; Bouillon, Isabelle; Krchňák, Viktor

    2008-01-01

    Combinatorial solid-phase synthesis of bis-heterocyclic compounds, characterized by the presence of two heterocyclic cores connected by a spacer of variable length/structure, provided structurally heterogeneous libraries with skeletal diversity. Both heterocyclic rings were assembled on resin in a combinatorial fashion.

  11. Safety impacts of bicycle infrastructure: A critical review.

    Science.gov (United States)

    DiGioia, Jonathan; Watkins, Kari Edison; Xu, Yanzhi; Rodgers, Michael; Guensler, Randall

    2017-06-01

    This paper takes a critical look at the present state of bicycle infrastructure treatment safety research, highlighting data needs. Safety literature relating to 22 bicycle treatments is examined, including findings, study methodologies, and data sources used in the studies. Some preliminary conclusions related to research efficacy are drawn from the available data and findings in the research. While the current body of bicycle safety literature points toward some defensible conclusions regarding the safety and effectiveness of certain bicycle treatments, such as bike lanes and removal of on-street parking, the vast majority treatments are still in need of rigorous research. Fundamental questions arise regarding appropriate exposure measures, crash measures, and crash data sources. This research will aid transportation departments with regard to decisions about bicycle infrastructure and guide future research efforts toward understanding safety impacts of bicycle infrastructure. Copyright © 2017 Elsevier Ltd and National Safety Council. All rights reserved.

  12. Bilateral tension pneumothorax resulting from a bicycle-to-bicycle collision.

    Science.gov (United States)

    Edwin, Frank; Sereboe, Lawrence; Tettey, Mark Mawutor; Aniteye, Ernest; Bankah, Patrick; Frimpong-Boateng, Kwabena

    2009-01-01

    Bilateral tension pneumothorax occurring as a result of recreational activity is exceedingly rare. A 10-year-old boy with no previous respiratory symptoms was involved in a bicycle-to-bicycle collision during play. He was the only one hurt. A few hours later, he was rushed to the general casualty unit of the emergency department of our institution with respiratory distress, diminished bilateral chest excursions and diminished breath sounds. The correct diagnosis was made after a chest radiograph was obtained in the course of resuscitation at the casualty unit. Pleural space needle decompression was suggestive of tension only on the right. Bilateral tube thoracostomies provided effective relief. He was discharged from hospital after a week in excellent health. This case illustrates the need for children to have safety instruction to reduce the risks of recreational bicycling. Chest radiography may be needed to establish the diagnosis of bilateral tension pneumothorax. Needle thoracostomy decompression is not always effective.

  13. Characterizing the speed and paths of shared bicycles in Lyon

    OpenAIRE

    Jensen , Pablo; Rouquier , Jean-Baptiste; Ovtracht , Nicolas; Robardet , Céline

    2010-01-01

    Thanks to numerical data gathered by Lyon's shared bicycling system V\\'elo'v, we are able to analyze 11.6 millions bicycle trips, leading to the first robust characterization of urban bikers' behaviors. We show that bicycles outstrip cars in downtown Lyon, by combining high speed and short paths.These data also allows us to calculate V\\'elo'v fluxes on all streets, pointing to interesting locations for bike paths.

  14. Bicycle: a bioinformatics pipeline to analyze bisulfite sequencing data.

    Science.gov (United States)

    Graña, Osvaldo; López-Fernández, Hugo; Fdez-Riverola, Florentino; González Pisano, David; Glez-Peña, Daniel

    2018-04-15

    High-throughput sequencing of bisulfite-converted DNA is a technique used to measure DNA methylation levels. Although a considerable number of computational pipelines have been developed to analyze such data, none of them tackles all the peculiarities of the analysis together, revealing limitations that can force the user to manually perform additional steps needed for a complete processing of the data. This article presents bicycle, an integrated, flexible analysis pipeline for bisulfite sequencing data. Bicycle analyzes whole genome bisulfite sequencing data, targeted bisulfite sequencing data and hydroxymethylation data. To show how bicycle overtakes other available pipelines, we compared them on a defined number of features that are summarized in a table. We also tested bicycle with both simulated and real datasets, to show its level of performance, and compared it to different state-of-the-art methylation analysis pipelines. Bicycle is publicly available under GNU LGPL v3.0 license at http://www.sing-group.org/bicycle. Users can also download a customized Ubuntu LiveCD including bicycle and other bisulfite sequencing data pipelines compared here. In addition, a docker image with bicycle and its dependencies, which allows a straightforward use of bicycle in any platform (e.g. Linux, OS X or Windows), is also available. ograna@cnio.es or dgpena@uvigo.es. Supplementary data are available at Bioinformatics online.

  15. Fatal Cervical Spine Injury Following a Bicycle Crash

    Directory of Open Access Journals (Sweden)

    Uhrenholt Lars

    2017-06-01

    Full Text Available Spinal injury following direct loading of the head and neck is a rare sequel of bicycle crashes. Fatal head injuries following bicycle crashes have been described in great detail and safety measures such as bicycle helmets have been developed accordingly. Less frequently, however, potentially severe cervical spine injuries have been described. We present the case of a middle-aged female who sustained an ultimately fatal cervical spine injury following a collision with a car whilst biking wearing a helmet. We discuss the literature regarding the protective effects of bicycle helmets, the relevance to cervical spine injury and legislation on mandatory use of helmets for injury prevention.

  16. Bicycle safety education for children from a developmental and learning perspective.

    Science.gov (United States)

    2014-01-01

    When children ride bicycles in and near traffic, they engage in a complicated task of combining motor skills and cognitive skills. In addition to developing bicycle-handling skills, bicycle safety education programs teach children how to ride safely ...

  17. Radical C-H functionalization to construct heterocyclic compounds.

    Science.gov (United States)

    Yu, Jin-Tao; Pan, Changduo

    2016-02-07

    Heterocyclic compounds are widely present in natural products, pharmaceuticals and bioactive molecules. Thus, organic and pharmaceutical chemists have been making extensive efforts to construct those heterocyclic frameworks through developing versatile and efficient synthetic strategies. The direct C-H functionalization via the radical pathway has emerged as a promising and dramatic approach towards heterocycles with high atom- and step-economy. Heterocyclic compounds such as coumarins, furans, benzofurans, xanthones, benzothiazoles, indoles, indolines, oxindoles, quinolines, isoquinolines, quinoxaline, and phenanthridines have been successfully synthesized by C-H functionalization through the radical pathway. In this review, recent advances on radical C-H functionalization to construct heterocyclic compounds are highlighted with discussions.

  18. Aspects and prospects of the chemistry of organic heterocycles (review)

    International Nuclear Information System (INIS)

    Schroth, W.

    1986-01-01

    The systematics of heterocycles, their place in organic chemistry, and their significance for theory and practice are discussed. Problems of the chemistry of heterocycles are discussed on the examples of systems with various types of conjugation and ring sizes. The focus is on the principles of synthesis of heterocycles, in particular, those based on acetylene, various C 3 fragments, carbon disulfide, and maleic anhydride. Individual sections of the survey are devoted to the role of heterocycles in biosynthesis, as well as certain problems common to the chemistry of heterocycles, biochemistry, and macromolecular chemistry

  19. Cyclists' attitudes toward policies encouraging bicycle travel: findings from the Taupo Bicycle Study in New Zealand.

    Science.gov (United States)

    Tin Tin, Sandar; Woodward, Alistair; Thornley, Simon; Langley, John; Rodgers, Anthony; Ameratunga, Shanthi

    2010-03-01

    Utility cycling provides substantial health, environmental and economic benefits. Despite a favourable trend in leisure-time cycling, cycling is infrequently used for everyday travel needs in New Zealand. This study investigated cyclists' attitudes toward environmental and policy measures that would encourage them to cycle more, particularly for a trip to work. A cross-sectional analysis was undertaken using baseline data obtained from the Taupo Bicycle Study, a web-based longitudinal study. The study population comprised 2469 cyclists, aged 16 years or over, who had enrolled in the 2006 Wattyl Lake Taupo Cycle Challenge. The majority (88%) reported the provision of bicycle lanes as an important factor that would encourage them to cycle more often, followed by bicycle paths (76%), better bicycle security (64%), reduced motor vehicle speed (55%) and bike friendly public transport (38%). Of those who reported travelling to work at least once a week (N = 2223), varying proportions reported shower facilities at work (61%), fewer difficult intersections (43%), rising fuel costs (41%), fewer car parks (27%), bike designed to commute (26%) and rising cost of car parking (25%) as important factors that would encourage them to cycle to work more often. There were important differences in these perceived influences defined by the participants' socio-demographic characteristics and current cycling habits.

  20. The tert-Amino Effect in Heterocyclic Chemistry. Synthesis of Spiro Heterocycles

    Directory of Open Access Journals (Sweden)

    Y. Morzherin

    2005-09-01

    Full Text Available The tert-amino reaction effect was examined. A new method to synthesize spiro heterocycles is presented. It was shown that the “tert-amino effect” could be applied to the formation of spiro-fused heterocycles. The formation of spiro compounds proceeds in most cases in good yields in a one-pot reaction.

  1. [Medical coverage of a road bicycle race].

    Science.gov (United States)

    Reifferscheid, Florian; Stuhr, Markus; Harding, Ulf; Schüler, Christine; Thoms, Jürgen; Püschel, Klaus; Kappus, Stefan

    2010-07-01

    Major sport events require adequate expertise and experience concerning medical coverage and support. Medical and ambulance services need to cover both participants and spectators. Likewise, residents at the venue need to be provided for. Concepts have to include the possibility of major incidents related to the event. Using the example of the Hamburg Cyclassics, a road bicycle race and major event for professional and amateur cyclists, this article describes the medical coverage, number of patients, types of injuries and emergencies. Objectives regarding the planning of future events and essential medical coverage are consequently discussed. (c) Georg Thieme Verlag Stuttgart-New York.

  2. Latent segmentation based count models: Analysis of bicycle safety in Montreal and Toronto.

    Science.gov (United States)

    Yasmin, Shamsunnahar; Eluru, Naveen

    2016-10-01

    The study contributes to literature on bicycle safety by building on the traditional count regression models to investigate factors affecting bicycle crashes at the Traffic Analysis Zone (TAZ) level. TAZ is a traffic related geographic entity which is most frequently used as spatial unit for macroscopic crash risk analysis. In conventional count models, the impact of exogenous factors is restricted to be the same across the entire region. However, it is possible that the influence of exogenous factors might vary across different TAZs. To accommodate for the potential variation in the impact of exogenous factors we formulate latent segmentation based count models. Specifically, we formulate and estimate latent segmentation based Poisson (LP) and latent segmentation based Negative Binomial (LNB) models to study bicycle crash counts. In our latent segmentation approach, we allow for more than two segments and also consider a large set of variables in segmentation and segment specific models. The formulated models are estimated using bicycle-motor vehicle crash data from the Island of Montreal and City of Toronto for the years 2006 through 2010. The TAZ level variables considered in our analysis include accessibility measures, exposure measures, sociodemographic characteristics, socioeconomic characteristics, road network characteristics and built environment. A policy analysis is also conducted to illustrate the applicability of the proposed model for planning purposes. This macro-level research would assist decision makers, transportation officials and community planners to make informed decisions to proactively improve bicycle safety - a prerequisite to promoting a culture of active transportation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. In vitro disposition profiling of heterocyclic compounds.

    Science.gov (United States)

    Keemink, Janneke; Wuyts, Benjamin; Nicolaï, Johan; Jonghe, Steven De; Stella, Alessandro; Herdewijn, Piet; Augustijns, Patrick; Annaert, Pieter

    2015-08-01

    Compound libraries that are screened for biological activity commonly contain heterocycles. Besides potency, drug-like properties need to be evaluated to ensure in vivo efficacy of test compounds. In this context, we determined hepatic and intestinal disposition profiles for 17 heterocyclic compounds. All studied compounds showed rapid uptake in suspended rat hepatocytes, whereas metabolism was poor and the rate-limiting step in hepatic elimination. In vitro assays demonstrated a relatively low solubility and high intestinal permeability. Based on these in vitro data, heterocycles were categorized in the biopharmaceutics classification system (BCS) and the biopharmaceutics drug disposition classification system (BDDCS) to predict disposition characteristics before clinical data are available. Our findings emphasized the importance to use hepatocytes in addition to microsomes to study metabolism, since the latter lack non-microsomal enzymes and cellular context. Moreover, intracellular exposure should be considered to gain insight in the relevant fraction of the compound available at the enzymatic site. Finally, the study reveals discrepancies associated with the classification of heterocycles in BCS versus BDDCS. These probably originate from the binary character of both systems. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Sulfamides in the synthesis of heterocyclic compounds

    International Nuclear Information System (INIS)

    Gazieva, Galina A; Kravchenko, Angelina N; Lebedev, Oleg V

    2000-01-01

    A comparative analysis of the structures and physicochemical properties of sulfamides and ureas has been performed. New procedures for the synthesis of heterocyclic compounds containing the sulfamide fragment are surveyed and the properties of the resulting compounds are described. The bibliography includes 112 references.

  5. -Heterocyclic Carbene Complexes of Mineral Acids

    KAUST Repository

    Brill, Marcel; Nahra, Fady; Gó mez-Herrera, Alberto; Zinser, Caroline; Cordes, David B.; Slawin, Alexandra M. Z.; Nolan, Steven P.

    2016-01-01

    We have synthesized and characterized new gold-N-heterocyclic carbene (NHC) complexes derived from the deprotonation of mineral acids. The use of sulfuric acid was a particularly interesting case. These complexes were tested in known gold-catalyzed reactions, such as the hydration of alkynes and the Meyer–Schuster rearrangement. They proved to be highly efficient in both reactions.

  6. -Heterocyclic Carbene Complexes of Mineral Acids

    KAUST Repository

    Brill, Marcel

    2016-11-08

    We have synthesized and characterized new gold-N-heterocyclic carbene (NHC) complexes derived from the deprotonation of mineral acids. The use of sulfuric acid was a particularly interesting case. These complexes were tested in known gold-catalyzed reactions, such as the hydration of alkynes and the Meyer–Schuster rearrangement. They proved to be highly efficient in both reactions.

  7. 40 CFR 52.1162 - Regulation for bicycle use.

    Science.gov (United States)

    2010-07-01

    ... safety education for bicyclists, motorists, children, students, street maintenance personnel and... as for a program of bicycle safety education including the motor vehicle operators license... bicycles share road space with motorized vehicles. (5) Bikeway means bike paths, bike lanes and bike routes...

  8. Synthetic strategy for bicyclic tetrapeptides HDAC inhibitors using ...

    Indian Academy of Sciences (India)

    Cyclic peptides show diverse biological activities and are considered as good therapeutic agents due to structural rigidity, receptor selectivity and biochemical stability. We have developed bicyclic tetrapeptide HDAC inhibitors based on different cyclic tetrapeptide scaffolds. For the synthesis of these bicyclic tetrapeptides, ...

  9. Modeling of speed distribution for mixed bicycle traffic flow

    Directory of Open Access Journals (Sweden)

    Cheng Xu

    2015-11-01

    Full Text Available Speed is a fundamental measure of traffic performance for highway systems. There were lots of results for the speed characteristics of motorized vehicles. In this article, we studied the speed distribution for mixed bicycle traffic which was ignored in the past. Field speed data were collected from Hangzhou, China, under different survey sites, traffic conditions, and percentages of electric bicycle. The statistics results of field data show that the total mean speed of electric bicycles is 17.09 km/h, 3.63 km/h faster and 27.0% higher than that of regular bicycles. Normal, log-normal, gamma, and Weibull distribution models were used for testing speed data. The results of goodness-of-fit hypothesis tests imply that the log-normal and Weibull model can fit the field data very well. Then, the relationships between mean speed and electric bicycle proportions were proposed using linear regression models, and the mean speed for purely electric bicycles or regular bicycles can be obtained. The findings of this article will provide effective help for the safety and traffic management of mixed bicycle traffic.

  10. In-depth analysis of bicycle hydraulic disc brakes

    Science.gov (United States)

    Maier, Oliver; Györfi, Benedikt; Wrede, Jürgen; Arnold, Timo; Moia, Alessandro

    2017-10-01

    Hydraulic Disc Brakes (HDBs) represent the most recent and innovative bicycle braking system. Especially Electric Bicycles (EBs), which are becoming more and more popular, are equipped with this powerful, unaffected by environmental influences, and low-wear type of brakes. As a consequence of the high braking performance, typical bicycle braking errors lead to more serious accidents. This is the starting point for the development of a Braking Dynamics Assistance system (BDA) to prevent front wheel lockup and nose-over (falling over the handlebars). One of the essential prerequisites for the system design is a better understanding of bicycle HDBs' characteristics. A physical simulation model and a test bench have been built for this purpose. The results of the virtual and real experiments conducted show a high correlation and allow valuable insights into HDBs on bicycles, which have not been studied scientifically in any depth so far.

  11. Anaerobic Degradation of Bicyclic Monoterpenes in Castellaniella defragrans

    Directory of Open Access Journals (Sweden)

    Edinson Puentes-Cala

    2018-02-01

    Full Text Available The microbial degradation pathways of bicyclic monoterpenes contain unknown enzymes for carbon–carbon cleavages. Such enzymes may also be present in the betaproteobacterium Castellaniella defragrans, a model organism to study the anaerobic monoterpene degradation. In this study, a deletion mutant strain missing the first enzyme of the monocyclic monoterpene pathway transformed cometabolically the bicyclics sabinene, 3-carene and α-pinene into several monocyclic monoterpenes and traces of cyclic monoterpene alcohols. Proteomes of cells grown on bicyclic monoterpenes resembled the proteomes of cells grown on monocyclic monoterpenes. Many transposon mutants unable to grow on bicyclic monoterpenes contained inactivated genes of the monocyclic monoterpene pathway. These observations suggest that the monocyclic degradation pathway is used to metabolize bicyclic monoterpenes. The initial step in the degradation is a decyclization (ring-opening reaction yielding monocyclic monoterpenes, which can be considered as a reverse reaction of the olefin cyclization of polyenes.

  12. Safety effects of permanent running lights for bicycles

    DEFF Research Database (Denmark)

    Madsen, Jens Chr. Overgaard; Andersen, T.; Lahrmann, Harry

    2013-01-01

    , including all recorded bicycle accidents with personal injury to the participating cyclist, is 19% lower for cyclists with permanent running lights mounted; indicating that the permanent bicycle running light significantly improves traffic safety for cyclists. The study shows that use of permanent bicycle......Making the use of daytime running lights mandatory for motor vehicles is generally documented to have had a positive impact upon traffic safety. Improving traffic safety for bicyclists is a focal point in the road traffic safety work in Denmark. In 2004 and 2005 a controlled experiment including...... 3845 cyclists was carried out in Odense, Denmark in order to examine, if permanent running lights mounted to bicycles would improve traffic safety for cyclists. The permanent running lights were mounted to 1845 bicycles and the accident rate was recorded through 12 months for this treatment group...

  13. Revitalization of Cycling in a Former Bicycle Kingdom: Beijing

    DEFF Research Database (Denmark)

    Zhao, Chunli; Carstensen, Trine Agervig; Olafsson, Anton Stahl

    This paper scrutinizes and analyses the relevant historical policy documents chronologically - from the 1960s to the present - in order to figure out the potentials of revitalizing the bicycle mode share in Beijing. Firstly, we targeted two top-drawer conflicts of the bicycle use, which are travel......- or commuting distance and motorised vehicle-oriented urban development. Secondly, we analysed how the various related policies resulted in the changing landscape of the bicycle mode share, including increasing in the bicycle mode share, created the conflicts and declined the bicycle mode share. The results...... are revealed by collection and analysis of historical material and interviews with key stakeholders. The historical material is obtained from libraries, online resources, and reports from professionals including urban designers, transportation engineers, research centres and politicians of the Beijing...

  14. Structural design of a composite bicycle fork

    International Nuclear Information System (INIS)

    Baldissera, Paolo; Delprete, Cristiana

    2014-01-01

    Highlights: • Case study about composite bicycle fork design. • Special requirements for a Student Team project. • FE model to evaluate stiffness, strength and potential failure modes. • Comparison of two manufacturing approaches. • FE model stiffness validation on the manufactured fork. - Abstract: Despite the wide literature on the mechanical behaviour of carbon/epoxy composites, it is rare to find practical methodological approaches in finite element design of structural components made by laminate layup. Through the case study of a special bicycle fork needed in a Student Team prototype, this paper proposes a simplified methodology as starting point for educational and manufacturing purposes. In order to compare two manufacturing solutions in terms of stiffness, strength and failure mode, a numerical model was implemented. Since the project requirements imposed to avoid standard destructive testing, the model validation was based on a posteriori linear stiffness comparison with the manufactured component. The slight discrepancies between experimental and numerical results were discussed in order to check their origin and to assess the reliability of the model. The overall methodology, even if complain with only a part of the safety standard requirements, shows to be reliable enough and can be the basis for further extension and refinement

  15. Finding the Speed of a Bicycle in Circular Motion by Measuring the Lean Angle of the Bicycle

    Science.gov (United States)

    Ben-Abu, Yuval; Wolfson, Ira; Yizhaq, Hezi

    2018-01-01

    We suggest an activity for measuring the speed of a bicycle going in circular motion by measuring the bicycle's lean angle. In this activity students will be able to feel the strength that is being activated on their bodies while they are moving in circular motion. They will also understand that it is impossible to ride in a circle without the…

  16. An international review of the frequency of single-bicycle crashes (SBCs) and their relation to bicycle modal share

    DEFF Research Database (Denmark)

    Schepers, Paul; Agerholm, Niels; Amoros, Emmanuelle

    2015-01-01

    of SBC casualties among the total number of road crash casualties increases proportionally less than the increase in bicycle modal share. Conclusions While most fatal injuries among cyclists are due to motor vehicle–bicycle crashes, most hospital admissions and emergency department attendances result...

  17. Characteristics of bicyclic sesquiterpanes in crude oils and petroleum products.

    Science.gov (United States)

    Yang, Chun; Wang, Zhendi; Hollebone, Bruce P; Brown, Carl E; Landriault, Mike

    2009-05-15

    This study presents a quantitative gas chromatography-mass spectrometry analysis of bicyclic sesquiterpanes (BSs) in numerous crude oils and refined petroleum products including light and mid-range distillate fuels, residual fuels, and lubricating oils collected from various sources. Ten commonly recognized bicyclic sesquiterpanes were determined in all the studied crude oils and diesel range fuels with principal dominance of BS3 (C(15)H(28)), BS5 (C(15)H(28)) and BS10 (C(16)H(30)), while they were generally not detected or in trace in light fuel oils like gasoline and kerosene and most lubricating oils. Laboratory distillation of crude oils demonstrated that sesquiterpanes were highly enriched in the medium distillation fractions of approximately 180 to 481 degrees C and were generally absent or very low in the light distillation fraction (boiling point to approximately 180 degrees C) and the heavy residual fraction (>481 degrees C). The effect of evaporative weathering on a series of diagnostic ratios of sesquiterpanes, n-alkanes, and biomarkers was evaluated with two suites of weathered oil samples. The change of abundance of sesquiterpanes was used to determine the extent of weathering of artificially evaporated crude oils and diesel. In addition to the pentacyclic biomarker C(29) and C(30) alphabeta-hopane, C(15) and C(16) sesquiterpanes might be alternative internal marker compounds to provide a direct way to estimate the depletion of oils, particularly diesels, in oil spill investigations. These findings may offer potential applications for both oil identification and oil-source correlation in cases where the tri- to pentacyclic biomarkers are absent due to refining or environmental weathering of oils.

  18. Methodological proposal for the implementation of shared bicycle applied to the Brazilian context

    OpenAIRE

    BARBOSA, PHILIPPE; Modesto de Sousa, Adriana; Azevedo Oliveira, Rodrigo; ESPANA, JUAN

    2016-01-01

    [EN] The main objective of this study is to analyze the bicycle rental system in the Federal District "Bike Brasilia". It aims to identify guidelines that supported the application process and consensus, disagreements and guidelines established by the Institute for Policies and Development in Transportation - ITDP and relate those listed by Zhang regarding rented bikes systems. This is an exploratory study based on the strategy of document analysis and its secondary sources: institutional doc...

  19. Assessing and Mapping of Road Surface Roughness based on GPS and Accelerometer Sensors on Bicycle-Mounted Smartphones

    Science.gov (United States)

    Shen, Jie; Wan, Mi; Shi, Jiafeng

    2018-01-01

    The surface roughness of roads is an essential road characteristic. Due to the employed carrying platforms (which are often cars), existing measuring methods can only be used for motorable roads. Until now, there has been no effective method for measuring the surface roughness of un-motorable roads, such as pedestrian and bicycle lanes. This hinders many applications related to pedestrians, cyclists and wheelchair users. In recognizing these research gaps, this paper proposes a method for measuring the surface roughness of pedestrian and bicycle lanes based on Global Positioning System (GPS) and accelerometer sensors on bicycle-mounted smartphones. We focus on the International Roughness Index (IRI), as it is the most widely used index for measuring road surface roughness. Specifically, we analyzed a computing model of road surface roughness, derived its parameters with GPS and accelerometers on bicycle-mounted smartphones, and proposed an algorithm to recognize potholes/humps on roads. As a proof of concept, we implemented the proposed method in a mobile application. Three experiments were designed to evaluate the proposed method. The results of the experiments show that the IRI values measured by the proposed method were strongly and positively correlated with those measured by professional instruments. Meanwhile, the proposed algorithm was able to recognize the potholes/humps that the bicycle passed. The proposed method is useful for measuring the surface roughness of roads that are not accessible for professional instruments, such as pedestrian and cycle lanes. This work enables us to further study the feasibility of crowdsourcing road surface roughness with bicycle-mounted smartphones. PMID:29562731

  20. Photometabolism of Heterocyclic Aromatic Compounds by Rhodopseudomonas palustris OU 11

    Science.gov (United States)

    Sasikala, C.; Ramana, C. V.; Rao, P. Raghuveer

    1994-01-01

    Rhodopseudomonas palustris OU 11 (ATCC 51186; DSM 7375) isolated from a pond of chemical industry effluent could anaerobically photometabolize heterocyclic aromatic compounds belonging to the pyridine and pyrazine groups only after a period of adaptation on pyrazinoic acid of 5 to 6 weeks. Growth on heterocyclic compounds was light dependent. The effects of various concentrations of heterocyclic compounds on growth suggest that higher concentrations of these compounds inhibit growth and are toxic. PMID:16349307

  1. Structural mechanisms of photoeffect in polyimide structures containing heterocyclic fragments

    International Nuclear Information System (INIS)

    Aleksandrova, E. L.

    2006-01-01

    Trends in the variation in the quantum yields of charge-carrier photogeneration in polyimide structures containing heterocyclic fragments are studied. It is shown that the efficiency of sensitization of polyimides depends on the donor and acceptor properties of the fragments of monomeric units of the polyimide. It is established that the range of spectral sensitivity for heterocyclic fragments representing intramolecular complexes with charge transport is wider than that for heterocycles that do not represent such complexes

  2. Beijing Bicycle - Stories from a Transformative Space

    DEFF Research Database (Denmark)

    Bagger-Petersen, Mai Corlin

    2012-01-01

    Ideas, words, images and stories travel from west to east – and from east to west. Stories are chosen and retold in different settings and images are reproduced and appropriated into new contexts – and in new times. Cinema, in this case the mainland Chinese, becomes both a space of production...... and a production of space that reveals how transnational and translocal mechanisms affect the cinematic language, transforming the images and stories chosen for the cinematic representation. Wang Xiaoshuai’s Beijing Bicycle (Shiqi Sui de Danche) (2001) is a result of transnational currents weaving the carpet...... relevant in a new context – that of the Chinese mainland society in the 21st century. Doreen Massey (2005: 9) defines space as “a simultaneity of stories-so-far”, a space that is constantly exploding and imploding with the influx of new and old stories. Within this theoretical framework Wang Xiaoshuai...

  3. New heterocyclic compounds from Ranunculus ternatus Thunb.

    Science.gov (United States)

    Feng, Zi-Ming; Zhan, Zhi-Lai; Yang, Ya-Nan; Jiang, Jian-Shuang; Zhang, Pei-Cheng

    2017-10-01

    Five new heterocyclic compounds, 5-α-d-fructofuranosylmethyl-furfural (1), 5-β-d-fructofuranosylmethyl-furfural (2), 5-β-d-fructopyranosylmethyl-furfural (3), 4-(2-((2S-2,3-dihydroxypropoxy)methyl)-5-formyl-1H-pyrrol-1-yl)butanoic acid (4), and 3S,4S-4,5,8-trihydroxy-3-(prop-1-en-2-yl)isochroman-1-one (5), were obtained from the root of Ranunculus ternatus Thunb., which is a traditional Chinese anti-tuberculosis medicine. Their structures were elucidated by UV, IR, HRESIMS, NMR data, and the comparison of experimental and calculated electronic circular dichroism (ECD) spectra. Notably, compounds 1-3 are rarely occurring furfural fructosides in natural sources. These heterocyclic compounds could be further studied for the synthetic chemists and pharmacologists due to the source and structural properties. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Associations between a walkability index and bicycle use in Denmark

    DEFF Research Database (Denmark)

    Madsen, T.; Christiansen, L.; Nielsen, Thomas Alexander Sick

    2012-01-01

    /day, and important health benefits can accrue from regular commuting cycling. Studies have shown a positive correlation between walkability attributes of neighborhood environments (street connectivity, and use mix, residential density, retail floor area ratio) and cycling. Results from Australia/Belgium show...... associations between measures of walkability and bicycle use for transport and the present study focuses on exploring whether these findings can be applied to a Danish setting where cycling culture differs and bicycle share is much higher (17% of all trips are by bicycle)...

  5. Bicyclic peptide inhibitor of urokinase-type plasminogen activator

    DEFF Research Database (Denmark)

    Roodbeen, Renée; Jensen, Berit Paaske; Jiang, Longguang

    2013-01-01

    The development of protease inhibitors for pharmacological intervention has taken a new turn with the use of peptide-based inhibitors. Here, we report the rational design of bicyclic peptide inhibitors of the serine protease urokinase-type plasminogen activator (uPA), based on the established...... investigated the solution structures of the bicyclic peptide by NMR spectroscopy to map possible conformations. An X-ray structure of the bicyclic-peptide-uPA complex confirmed an interaction similar to that for the previous upain-1/upain-2-uPA complexes. These physical studies of the peptide...

  6. Use and activity levels on newly built bicycle playgrounds

    DEFF Research Database (Denmark)

    Schipperijn, Jasper; Hansen, Christine Kier; Rask, Simon

    2015-01-01

    Increasing the use of urban green space (UGS) as well as increasing cycling could potentially help address the growing inactivity problem. Three bicycle playgrounds were designed based on a participatory process and afterwards constructed in the UGS along a cycle-route on the historic outer defence...... close to one of the sites. A future study involving objective before and after measures when a new bicycle playground is build will be needed to reveal if bicycle playgrounds can provide additional activity to its users, or ‘just’ a different type of activity, in a different location....

  7. Water purification by reverse osmosis using heterocyclic polymer membranes

    Science.gov (United States)

    Scott, H.

    1972-01-01

    Pyrrone (polyimidazopyrrolone) polymers are a new class of thermally stable, radiation and chemical resistant aromatic-heterocyclic polymers featuring a greater chemical and mechanical durability than cellulose acetate.

  8. A Novel Electric Bicycle Battery Monitoring System Based on Android Client

    Directory of Open Access Journals (Sweden)

    Chuanxue Song

    2017-01-01

    Full Text Available The battery monitoring system (BMS plays a crucial role in maintaining the safe operation of the lithium battery electric bicycle and prolonging the life of the battery pack. This paper designed a set of new battery monitoring systems based on the Android system and ARM single-chip microcomputer to enable direct management of the lithium battery pack and convenient monitoring of the state of the battery pack. The BMS realizes the goal of monitoring the voltage, current, and ambient temperature of lithium batteries, estimating the state of charge (SOC and state of health (SOH, protecting the battery from abuse during charging or discharging, and ensuring the consistency of the batteries by integrating the passive equalization circuit. The BMS was proven effective and feasible through several tests, including charging/discharging, estimation accuracy, and communication tests. The results indicated that the BMS could be used in the design and application of the electric bicycle.

  9. Heterocyclic Anticancer Compounds: Recent Advances and the Paradigm Shift towards the Use of Nanomedicine’s Tool Box

    Directory of Open Access Journals (Sweden)

    Pedro Martins

    2015-09-01

    Full Text Available The majority of heterocycle compounds and typically common heterocycle fragments present in most pharmaceuticals currently marketed, alongside with their intrinsic versatility and unique physicochemical properties, have poised them as true cornerstones of medicinal chemistry. Apart from the already marketed drugs, there are many other being investigated for their promising activity against several malignancies. In particular, anticancer research has been capitalizing on the intrinsic versatility and dynamic core scaffold of these compounds. Nevertheless, as for any other promising anticancer drugs, heterocyclic compounds do not come without shortcomings. In this review, we provide for a concise overview of heterocyclic active compounds and families and their main applications in medicine. We shall focus on those suitable for cancer therapy while simultaneously addressing main biochemical modes of action, biological targets, structure-activity relationships as well as intrinsic limitation issues in the use of these compounds. Finally, considering the advent of nanotechnology for effective selective targeting of drugs, we shall discuss fundamental aspects and considerations on nanovectorization of such compounds that may improve pharmacokinetic/pharmacodynamic properties of heterocycles.

  10. Street Intersection Characteristics and Their Impacts on Perceived Bicycling Safety

    Science.gov (United States)

    2018-01-01

    Safety concern is one of the core issues that deter people from bicycling in the US. Earlier studies have explored the associations between intersection design characteristics and bicyclist safety perceptions. Research shows that there are significan...

  11. Using Smartphones to Collect Bicycle Travel Data in Texas

    Science.gov (United States)

    2012-08-08

    Researchers believed that if smartphones could prove to be an effective tool for collecting bicycle travel data, the information could be used for aiding decision making as to what types of facilities users prefer and guiding decisions about future f...

  12. Associations between bicycling and carotid arterial stiffness in adolescents

    DEFF Research Database (Denmark)

    Ried-Larsen, M; Grøntved, A; Østergaard, Lars

    2015-01-01

    Youth Heart Study. Total frequency of bicycle usage was assessed by self-report, and carotid arterial stiffness was assessed using B-mode ultrasound. After adjusting for pubertal status, body height, and objectively measured physical activity and other personal lifestyle and demographic factors, boys......The aim of the study was to investigate the associations between bicycling and carotid arterial stiffness, independent of objectively measured moderate-and-vigorous physical activity. This cross-sectional study included 375 adolescents (age 15.7 ± 0.4 years) from the Danish site of the European...... using their bicycle every day of the week displayed a higher carotid arterial compliance {standard beta 0.47 [95% confidence interval (CI) 0.07-0.87]} and distension [standard beta 0.38 (95% CI -0.04 to 0.81)]. Boys using their bicycle every day of the week furthermore displayed a lower Young's elastic...

  13. Safety effects of permanent running lights for bicycles

    DEFF Research Database (Denmark)

    Madsen, Jens Chr. Overgaard; Andersen, T.; Lahrmann, Harry

    2013-01-01

    Making the use of daytime running lights mandatory for motor vehicles is generally documented to have had a positive impact upon traffic safety. Improving traffic safety for bicyclists is a focal point in the road traffic safety work in Denmark. In 2004 and 2005 a controlled experiment including...... 3845 cyclists was carried out in Odense, Denmark in order to examine, if permanent running lights mounted to bicycles would improve traffic safety for cyclists. The permanent running lights were mounted to 1845 bicycles and the accident rate was recorded through 12 months for this treatment group...... and 2000 other bicyclists, the latter serving as a control group without bicycle running lights. The safety effect of the running lights is analysed by comparing incidence rates – number of bicycle accidents recorded per man-month – for the treatment group and the control group. The incidence rate...

  14. Fluid Mechanics of a High Performance Racing Bicycle Wheel

    Science.gov (United States)

    Mercat, Jean-Pierre; Cretoux, Brieuc; Huat, Francois-Xavier; Nordey, Benoit; Renaud, Maxime; Noca, Flavio

    2013-11-01

    In 2012, MAVIC released the most aerodynamic bicycle wheel on the market, the CXR 80. The french company MAVIC has been a world leader for many decades in the manufacturing of bicycle wheels for competitive events such as the Olympic Games and the Tour de France. Since 2010, MAVIC has been in a research partnership with the University of Applied Sciences in Geneva, Switzerland, for the aerodynamic development of bicycle wheels. While most of the development up to date has been performed in a classical wind tunnel, recent work has been conducted in an unusual setting, a hydrodynamic towing tank, in order to achieve low levels of turbulence and facilitate quantitative flow visualization (PIV). After a short introduction on the aerodynamics of bicycle wheels, preliminary fluid mechanics results based on this novel setup will be presented.

  15. Comparative life cycle assessment of ghana-made bamboo-frame bicycle and conventional bicycles assembled and used in the Netherlands

    NARCIS (Netherlands)

    Agyekum, E.O.; Fortuin, K.P.J.; Harst, van der E.J.M.

    2014-01-01

    In order to assess the sustainability of bamboo-framed bicycles produced in Ghana, an environmental and social life cycle assessments (LCA) were performed. For the environmental LCA, a bamboo-frame bicycle was compared with aluminium- and steel-frame bicycles, focussing on processes related to the

  16. Methodological proposal for the implementation of shared bicycle applied to the Brazilian context

    Energy Technology Data Exchange (ETDEWEB)

    Espana, J.P.; Barbosa, P.

    2016-07-01

    The main objective of this study is to analyze the bicycle rental system in the Federal District {sup B}ike Brasilia{sup .} It aims to identify guidelines that supported the application process and consensus, disagreements and guidelines established by the Institute for Policies and Development in Transportation - ITDP and relate those listed by Zhang regarding rented bikes systems. This is an exploratory study based on the strategy of document analysis and its secondary sources: institutional documents, basic design, procurement and other official documents made exclusively for this study. To support the discussion, a systematic literature review of the rules describing specially: sustainability, transport, urban mobility, bicycle rental and environment. The results reveal that while some of the parameters and indicators of efficiency are met on time, the bicycle sharing system of the city of Brasilia, has weaknesses that can lead to inefficiency and impracticality of maintaining and expanding such services. On the other hand, Bike Brasilia partially fulfills the principles enumerated by Zhang and lacks improvement in the steps for the successful operation of the system. (Author)

  17. Palladium-catalyzed allylation of tautomerizable heterocycles with alkynes.

    Science.gov (United States)

    Lu, Chuan-Jun; Chen, Dong-Kai; Chen, Hong; Wang, Hong; Jin, Hongwei; Huang, Xifu; Gao, Jianrong

    2017-07-21

    A method for the allylic amidation of tautomerizable heterocycles was developed by a palladium catalyzed allylation reaction with 100% atom economy. A series of structurally diverse N-allylic substituted heterocycles can be synthesized in good yields with high chemo-, regio-, and stereoselectivities under mild conditions.

  18. Alkynylation of heterocyclic compounds using hypervalent iodine reagent.

    Science.gov (United States)

    Kamlar, M; Císařová, I; Veselý, J

    2015-03-14

    The alkynylation of various nitrogen- and/or sulphur-containing heterocyclic compounds using hypervalent iodine TMS-EBX by utilization of tertiary amines under mild conditions is described. The developed metal-free methodology furnishes the corresponding alkynylated heterocycles bearing quaternary carbon in high yields.

  19. Finding the speed of a bicycle in circular motion by measuring the lean angle of the bicycle

    Science.gov (United States)

    Ben-Abu, Yuval; Wolfson, Ira; Yizhaq, Hezi

    2018-05-01

    We suggest an activity for measuring the speed of a bicycle going in circular motion by measuring the bicycle’s lean angle. In this activity students will be able to feel the strength that is being activated on their bodies while they are moving in circular motion. They will also understand that it is impossible to ride in a circle without the bicycle leaning at an angle, an action that is performed intuitively.

  20. α-Diazo oxime ethers for N-heterocycle synthesis.

    Science.gov (United States)

    Choi, Subin; Ha, Sujin; Park, Cheol-Min

    2017-06-01

    This Feature Article introduces the preparation and synthetic utility of α-diazo oxime ethers. α-Oximino carbenes are useful synthons for N-heterocycles, and can be easily prepared from α-diazo oxime ethers as precursors. We begin with the preparation of α-diazo oxime ethers and their application in [3+2] cycloaddition. It turns out that the nature of metals bound to carbenes plays a crucial role in modulating the reactivity of α-oximino carbenes, in which copper carbenes smoothly react with enamines, whereas the less reactive enol ethers and nitriles require gold carbenes. In Section 3.2, a discussion on N-O and C-H bond activation is presented. Carbenes derived from diazo oxime ethers show unique reactivity towards N-O and C-H bond activation, in which the proximity of the two functionalities, carbene and oxime ether, dictates the preferred reaction pathways toward pyridines, pyrroles, and 2H-azirines. In Section 3.3, the development of tandem reactions based on α-diazo oxime ethers is discussed. The nature of carbenes in which whether free carbenes or metal complexes are involved dissects the pathway and forms different types of 2H-azirines. The 2H-azirine formation turned out to be an excellent platform for the tandem synthesis of N-heterocycles including pyrroles and pyridines. In the last section, we describe the electrophilic activation of 2H-azirines with vinyl carbenes and oximino carbenes. The resulting azirinium species undergo rapid ring expansion rearrangements to form pyridines and pyrazines.

  1. Synthesis of boron-containing heterocyclic compounds

    International Nuclear Information System (INIS)

    Azev, Yuri; Slepukhina, Irina; Gabel, Detlef

    2004-01-01

    The synthesis of boron-containing 1,3,5-triazines and 1,2,4-triazines is described. Derivatives of 1,3,5-triazine containing the o-carborane cluster have been obtained by reacting the corresponding propargyl derivatives with B 10 H 14 . Derivatives of 1,2,4-triazine containing the B 12 H 12 2- cluster have been obtained by nucleophilic substitution of ethylsulfone derivatives with B 12 H 11 SH 2- . They have been isolated in their ring-protonated form. Reaction of RNH 2 -B 8 H 11 NH-R with stericly demanding heterocycles failed, either for steric or for solubility reasons

  2. Reviving a ghost in the history of technology: the social construction of the recumbent bicycle.

    Science.gov (United States)

    Ahmed, Hassaan; Qureshi, Omer Masood; Khan, Abid Ali

    2015-02-01

    Recumbent bicycles have never truly been associated with international cycling. Conventional safety (upright) bicycles have long been at the center of the cycling world, for both sport and transportation. This is despite the fact that recumbent bicycles are faster, more comfortable, and more efficient than the upright bicycles. The aim of this article is to explain the historical and social perspectives that led to the rejection of the recumbent bicycle by utilizing the theory of Social Construction of Technology (SCOT) and Bijker's two power theory, providing a contrast with the adoption of the safety bicycle.

  3. The PurdueTracer: An Energy-Efficient Human-Powered Hydraulic Bicycle with Flexible Operation and Software Aids

    Directory of Open Access Journals (Sweden)

    Gianluca Marinaro

    2018-01-01

    Full Text Available Hydrostatic transmissions (HT are widely applied to heavy-duty mobile applications because of the advantages of layout flexibility, power to weight ratio, and ease of control. Though applications of fluid power in light-duty vehicles face challenges, including the unavailability of off-the-shelf components suitable to the power scale, there are potential advantages for HTs in human-powered vehicles, such as bicycles, the most important one being the energy-saving advantage achievable through regenerative braking in a hybrid HT. This paper describes an innovative design for a hydraulic hybrid bicycle, i.e., the PurdueTracer. The PurdueTracer is an energy-efficient human-powered hydraulic bicycle with flexible operation and software aids. An open-circuit hydraulic hybrid transmission allows PurdueTracer to operate in four modes: Pedaling, Charging, Boost, and Regeneration, to satisfy users’ need for different riding occasions. An aluminum chassis that also functions as a system reservoir was customized for the PurdueTracer to optimize the durability, riding comfort, and space for components. The selection of the hydraulic components was performed by creating a model of the bicycle in AMESim simulation software and conducting a numerical optimization based on the model. The electronic system equipped users with informative feedback showing the bicycle performance, intuitive execution of functions, and comprehensive guidance for operation. This paper describes the design approach and the main results of the PurdueTracer, which also won the 2017 National Fluid Power Association Fluid Power Vehicle Challenge. This championship serves to prove the excellence of this vehicle in terms of effectiveness, efficiency, durability, and novelty.

  4. N-heterocyclic carbene complexes of silver and gold as novel tools against breast cancer progression.

    Science.gov (United States)

    Saturnino, Carmela; Barone, Ines; Iacopetta, Domenico; Mariconda, Annaluisa; Sinicropi, Maria Stefania; Rosano, Camillo; Campana, Antonella; Catalano, Stefania; Longo, Pasquale; Andò, Sebastiano

    2016-12-01

    Metal carbenic complexes have received considerable attention in both the catalysis and biological fields for their potential applications in cancer and antimicrobial therapies. A small series of new silver and gold N-heterocyclic carbene complexes has been designed and synthesized. Among the tested complexes, one compound was particularly active in inhibiting anchorage-dependent and -independent breast cancer proliferation, and inducing cell apoptosis via a mitochondria-related process. The antitumor activity was associated to the transcriptional activation of the tumor suppressor gene p53 in an Sp1-dependent manner, as evidenced by biological and docking studies. Our results highlight the importance and the versatility of N-heterocyclic carbene complexes of gold and silver as useful tools against breast cancer progression.

  5. How similar are two-unit bicycle and motorcycle crashes?

    Science.gov (United States)

    Haworth, Narelle; Debnath, Ashim Kumar

    2013-09-01

    This paper explores the similarities and differences between bicycle and motorcycle crashes with other motor vehicles. If similar treatments can be effective for both bicycle and motorcycle crashes, then greater benefits in terms of crash costs saved may be possible for the same investment in treatments. To reduce the biases associated with under-reporting of these crashes to police, property damage and minor injury crashes were excluded. The most common crash type for both bicycles (31.1%) and motorcycles (24.5%) was intersection from adjacent approaches. Drivers of other vehicles were coded most at fault in the majority of two-unit bicycle (57.0%) and motorcycle crashes (62.7%). The crash types, patterns of fault and factors affecting fault were generally similar for bicycle and motorcycle crashes. This confirms the need to combat the factors contributing to failure of other drivers to yield right of way to two-wheelers, and suggest that some of these actions should prove beneficial to the safety of both motorized and non-motorized two-wheelers. In contrast, child bicyclists were more often at fault, particularly in crashes involving a vehicle leaving the driveway or footpath. The greater reporting of violations by riders and drivers in motorcycle crashes also deserves further investigation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Reduced Dynamics of the Non-holonomic Whipple Bicycle

    Science.gov (United States)

    Boyer, Frédéric; Porez, Mathieu; Mauny, Johan

    2018-06-01

    Though the bicycle is a familiar object of everyday life, modeling its full nonlinear three-dimensional dynamics in a closed symbolic form is a difficult issue for classical mechanics. In this article, we address this issue without resorting to the usual simplifications on the bicycle kinematics nor its dynamics. To derive this model, we use a general reduction-based approach in the principal fiber bundle of configurations of the three-dimensional bicycle. This includes a geometrically exact model of the contacts between the wheels and the ground, the explicit calculation of the kernel of constraints, along with the dynamics of the system free of any external forces, and its projection onto the kernel of admissible velocities. The approach takes benefits of the intrinsic formulation of geometric mechanics. Along the path toward the final equations, we show that the exact model of the bicycle dynamics requires to cope with a set of non-symmetric constraints with respect to the structural group of its configuration fiber bundle. The final reduced dynamics are simulated on several examples representative of the bicycle. As expected the constraints imposed by the ground contacts, as well as the energy conservation, are satisfied, while the dynamics can be numerically integrated in real time.

  7. The Bicycle Compatibility Index : a level of service concept, implementation manual

    Science.gov (United States)

    1998-11-01

    Currently, no methodology is widely accepted by engineers, planners, or bicycle coordinators that will allow them to determine how compatible a roadway is for allowing efficient operation of both bicycles and motor vehicles. Determining how existing ...

  8. Daily Bicycling in Older Adults May Be Effective to Reduce Fall Risks - A Case Control Study.

    Science.gov (United States)

    Batcir, Shani; Melzer, Itshak

    2018-01-18

    Older adults gain many health benefits from riding bicycles regularly. We aimed to explore whether older persons who ride bicycles regularly have better balance than controls. Balance control and voluntary stepping were assessed in 20 older adults aged 65 to 85 who live in an agricultural community village who regularly ride bicycles (BR), and 30 age- and gender-matched non-bicycle riders (NBR). Self-reported function and fear of fall were also assessed. Bicycle riders showed significantly better balance, faster voluntary stepping, and better self-reported advanced lower extremity function compared with NBR. The results might suggest that bicycling regularly preserves balance control and speed of voluntary stepping in older adults because bicycling might maintain specific balance coordination patterns. The results should be treated with caution since BR were older adults who selected an active life style (i.e., bicycling as well as living in an agricultural village) that may bias the results.

  9. Interventions in Bicycle Infrastructure, Lessons from Dutch and Danish Cases

    DEFF Research Database (Denmark)

    van Goeverden, K.; Nielsen, Thomas Alexander Sick; Harder, Henrik

    2015-01-01

    of interventions in bicycle infrastructure on travel choices, safety, design appreciation, and other factors. These clarify under which conditions certain measures are effective or not and inform about the effectiveness of improving a single route versus upgrading a whole network. The information from the studies...... to be still generally valid. In addition to studies that traditionally focus on dedicated bicycle infrastructure, two cases of shared space are discussed, a rather new type of intervention that assumes mixed use of infrastructure. One case is from Denmark, the other from the Netherlands. The paper will so...... uncover the valuable results of the possibly largest evaluations of interventions in bicycle infrastructure ever made, verify these by examining more recent studies, and contribute to the discussion of shared space....

  10. Predicting Public Bicycle Adoption Using the Technology Acceptance Model

    Directory of Open Access Journals (Sweden)

    Benjamin T. Hazen

    2015-10-01

    Full Text Available Bicycle sharing programs provide a sustainable mode of urban transportation. Although cities across the globe have developed these systems for their citizens and visitors, usage rates are not as high as anticipated. This research uses the technology acceptance model as the basis to understand one’s intention to adopt bicycle sharing programs. Using survey data derived from 421 participants in Beijing, China, the proposed covariance-based structural equation model consisting of perceived quality, perceived convenience, and perceived value is found to predict 50.5% of the variance in adoption intention. The findings of this research contribute to theory and practice in the burgeoning literature on public bicycle systems and sustainable urban transportation by offering a theoretical lens through which to consider system adoption, and providing information to practitioners as to what factors might contribute most to adoption.

  11. Using magnetorheological fluids in an innovative hybrid bicycle damper

    International Nuclear Information System (INIS)

    Shiao, Y J; Nguyen, T S

    2015-01-01

    Magnetorheological fluids are capable of changing their viscosity quickly. This can provide good controllability and fast dynamic response. A conventional passive suspension system with air spring or hydraulic damper has simple design and financial benefit for bicycles, but its operation is uncontrollable and non-adaptive. This paper presented a semi-active hybrid bicycle suspension system which combines conventional air spring and a new magnetorheological damping brake together to reduce vibration of a bicycle. A multi-layer magnetorheological brake and linkage mechanism are connected to bike fork to form the adaptive damping part of the innovative hybrid suspension system. The simulation results proved that the semi-active suspension system can reduce bike vibration effectively. (paper)

  12. Driver braking behavior analysis to improve autonomous emergency braking systems in typical Chinese vehicle-bicycle conflicts.

    Science.gov (United States)

    Duan, Jingliang; Li, Renjie; Hou, Lian; Wang, Wenjun; Li, Guofa; Li, Shengbo Eben; Cheng, Bo; Gao, Hongbo

    2017-11-01

    Bicycling is one of the fundamental modes of transportation especially in developing countries. Because of the lack of effective protection for bicyclists, vehicle-bicycle (V-B) accident has become a primary contributor to traffic fatalities. Although AEB (Autonomous Emergency Braking) systems have been developed to avoid or mitigate collisions, they need to be further adapted in various conflict situations. This paper analyzes the driver's braking behavior in typical V-B conflicts of China to improve the performance of Bicyclist-AEB systems. Naturalistic driving data were collected, from which the top three scenarios of V-B accidents in China were extracted, including SCR (a bicycle crossing the road from right while a car is driving straight), SCL (a bicycle crossing the road from left while a car is driving straight) and SSR (a bicycle swerving in front of the car from right while a car is driving straight). For safety and data reliability, a driving simulator was employed to reconstruct these three scenarios and some 25 licensed drivers were recruited for braking behavior analysis. Results revealed that driver's braking behavior was significantly influenced by V-B conflict types. Pre-decelerating behaviors were found in SCL and SSR conflicts, whereas in SCR the subjects were less vigilant. The brake reaction time and brake severity in lateral V-B conflicts (SCR and SCL) was shorter and higher than that in longitudinal conflicts (SSR). The findings improve their applications in the Bicyclist-AEB and test protocol enactment to enhance the performance of Bicyclist-AEB systems in mixed traffic situations especially for developing countries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Evaluation and application of microwave-assisted extraction and dispersive liquid-liquid microextraction followed by high-performance liquid chromatography for the determination of polar heterocyclic aromatic amines in hamburger patties.

    Science.gov (United States)

    Aeenehvand, Saeed; Toudehrousta, Zahra; Kamankesh, Marzieh; Mashayekh, Morteza; Tavakoli, Hamid Reza; Mohammadi, Abdorreza

    2016-01-01

    This study developed an analytical method based on microwave-assisted extraction and dispersive liquid-liquid microextraction followed by high-performance liquid chromatography for the determination of three polar heterocyclic aromatic amines from hamburger patties. Effective parameters controlling the performance of the microextraction process, such as the type and volume of extraction and disperser solvents, microwave time, nature of alkaline aqueous solution, pH and salt amount, were optimized. The calibration graphs were linear in the range of 1-200 ng g(-1), with a coefficient of determination (R(2)) better than 0.9993. The relative standard deviations (RSD) for seven analyses were between 3.2% and 6.5%. The recoveries of those compounds in hamburger patties were from 90% to 105%. Detection limits were between 0.06 and 0.21 ng g(-1). A comparison of the proposed method with the existing literature demonstrates that it is a simple, rapid, highly selective and sensitive, and it gives good enrichment factors and detection limits for determining HAAs in real hamburger patties samples. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Asymmetric Catalytic Aza-Diels-Alder/Ring-Closing Cascade Reaction Forming Bicyclic Azaheterocycles by Trienamine Catalysis.

    Science.gov (United States)

    Li, Yang; Barløse, Casper; Jørgensen, Julie; Carlsen, Bjørn Dreiø; Jørgensen, Karl Anker

    2017-01-01

    An asymmetric catalytic aza-Diels-Alder/ring-closing cascade reaction between acylhydrazones and in situ formed trienamines is presented. The reaction proceeds through a formal aza-Diels-Alder cycloaddition, followed by a ring-closing reaction forming the hemiaminal ring leading to chiral bicyclic azaheterocycles in moderate to good yield (up to 71 %), good enantio- (up to 92 % ee) and diastereoselectivity (up to >20:1 d.r.). Furthermore, transformations are presented to show the potential application of the formed product. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Synthesis of fused bicyclic piperidines: potential bioactive templates for medicinal chemistry.

    Science.gov (United States)

    Zhou, Jinglan; Campbell-Conroy, Erica L; Silina, Alina; Uy, Johnny; Pierre, Fabrice; Hurley, Dennis J; Hilgraf, Nicole; Frieman, Bryan A; DeNinno, Michael P

    2015-01-02

    An array of six pyridyl-substituted fused bicyclic piperidines was prepared as novel cores for medicinal chemistry. For maximum diversity, the size of the fused ring varied from three to six atoms and contained up to two oxygen atoms. The pyridine ring was incorporated to improve physicochemical properties and to challenge the robustness of the chemistry. The presence of the pyridine did interfere with our initial approaches to these molecules, and in several instances, a blocking strategy had to be employed. These new scaffolds possess high sp3 character and may prove useful in multiple medicinal chemistry applications.

  16. Theoretical study of ionization and one-electron oxidation potentials of N-heterocyclic compounds.

    Science.gov (United States)

    Sviatenko, Liudmyla K; Gorb, Leonid; Hill, Frances C; Leszczynski, Jerzy

    2013-05-15

    A number of density functionals was utilized to predict gas-phase adiabatic ionization potentials (IPs) for nitrogen-rich heterocyclic compounds. Various solvation models were applied to the calculation of difference in free energies of solvation of oxidized and reduced forms of heterocyclic compounds in acetonitrile (AN) for correct reproduction of their standard oxidation potentials. We developed generally applicable protocols that could successfully predict the gas-phase adiabatic ionization potentials of nitrogen-rich heterocyclic compounds and their standard oxidation potentials in AN. This approach is supported by a MPW1K/6-31+G(d) level of theory which uses SMD(UA0) approximation for estimation of solvation energy of neutral molecules and PCM(UA0) model for ionized ones. The mean absolute derivation (MAD) and root mean square error (RMSE) of the current theoretical models for IP are equal to 0.22 V and 0.26, respectively, and for oxidation potentials MAD = 0.13 V and RMSE = 0.17. Copyright © 2013 Wiley Periodicals, Inc.

  17. Adsorption Characteristics of DNA Nucleobases, Aromatic Amino Acids and Heterocyclic Molecules on Silicene and Germanene Monolayers

    KAUST Repository

    Hussain, Tanveer

    2017-09-14

    Binding of DNA/RNA nucleobases, aromatic amino acids and heterocyclic molecules on two-dimensional silicene and germanene sheets have been investigated for the application of sensing of biomolecules using first principle density functional theory calculations. Binding energy range for nucleobases, amino acids and heterocyclic molecules with both the sheets have been found to be (0.43-1.16eV), (0.70-1.58eV) and (0.22-0.96eV) respectively, which along with the binding distances show that these molecules bind to both sheets by physisorption and chemisorption process. The exchange of electric charges between the monolayers and the incident molecules has been examined by means of Bader charge analysis. It has been observed that the introduction of DNA/RNA nucleobases, aromatic amino acids and heterocyclic molecules alters the electronic properties of both silicene and germanene nano sheets as studied by plotting the total (TDOS) and partial (PDOS) density of states. The DOS plots reveal the variation in the band gaps of both silicene and germanene caused by the introduction of studied molecules. Based on the obtained results we suggest that both silicene and germanene monolayers in their pristine form could be useful for sensing of biomolecules.

  18. Bicycling to Work and Primordial Prevention of Cardiovascular Risk

    DEFF Research Database (Denmark)

    Grøntved, Anders; Koivula, Robert W; Johansson, Ingegerd

    2016-01-01

    of incident obesity, hypertension, hypertriglyceridemia, and impaired glucose tolerance, comparing individuals who commuted to work by bicycle with those who used passive modes of transportation. We also examined the relationship of change in commuting mode with incidence of these clinical risk factors......% CI 0.74-0.91) compared with participants not cycling to work at both times points or who switched from cycling to other modes of transport during follow-up. CONCLUSIONS: These data suggest that commuting by bicycle to work is an important strategy for primordial prevention of clinical cardiovascular...... risk factors among middle-aged men and women....

  19. Wireless controller and smartphone based interaction system for electric bicycles.

    Directory of Open Access Journals (Sweden)

    Jorge REVUELTA HERRERO

    2016-07-01

    Full Text Available Throughout the last years, great improvements have been made in the automotive industry, a sector with a high impact in both economics and social environments. Many development efforts have targeted on satisfying the need of providing smart environments to the end user in vehicles, such as cars. This paper proposes a brand-new solution in the automotive field, consisting of a new product family which aims to transform the traditional bicycle to an electric bicycle using an architecture that provides an adaptive environment to the user, improving the driving experience enabling value-added services.

  20. Sulfur ylides in the synthesis of heterocyclic and carbocyclic compounds

    International Nuclear Information System (INIS)

    Lakeev, Sergei N; Maydanova, Irina O; Galin, Fanur Z; Tolstikov, Genrikh A

    2001-01-01

    Data on the use of sulfonium ylides in the synthesis of carbocyclic and heterocyclic compounds published over the last 15 years are analysed, systematised and generalised. The bibliography includes 139 references.

  1. New heterocyclic compounds: Synthesis and antitrypanosomal properties.

    Science.gov (United States)

    Pomel, S; Dubar, F; Forge, D; Loiseau, P M; Biot, C

    2015-08-15

    Three new series of quinoline, quinolone, and benzimidazole derivatives were synthesized and evaluated in vitro against Trypanosoma brucei gambiense. In the quinoline series, the metallo antimalarial drug candidate (ferroquine, FQ) and its ruthenium analogue (ruthenoquine, RQ, compound 13) showed the highest in vitro activities with IC50 values around 0.1 μM. Unfortunately, both compounds failed to cure Trypanosoma brucei brucei infected mice in vivo. The other heterocyclic compounds were active in vitro with IC50 values varying from 0.8 to 34 μM. One of the most interesting results was a fluoroquinolone derivative (compound 2) that was able to offer a survival time of 8 days after a treatment at the single dose of 100 μmol/kg by intraperitoneal route. Although no clear-cut structure-activity relationships emerged, further pharmacomodulations are worth to be developed in this series. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Multicomponent reactions: A simple and efficient route to heterocyclic phosphonates

    Science.gov (United States)

    2016-01-01

    Summary Multicomponent reactions (MCRs) are one of the most important processes for the preparation of highly functionalized organic compounds in modern synthetic chemistry. As shown in this review, they play an important role in organophosphorus chemistry where phosphorus reagents are used as substrates for the synthesis of a wide range of phosphorylated heterocycles. In this article, an overview about multicomponent reactions used for the synthesis of heterocyclic compounds bearing a phosphonate group on the ring is given. PMID:27559377

  3. Immobilization of N-Heterocyclic Carbene Compounds: A Synthetic Perspective.

    Science.gov (United States)

    Zhong, Rui; Lindhorst, Anja C; Groche, Florian J; Kühn, Fritz E

    2017-02-08

    Over the course of the past 15 years the success story of N-heterocyclic carbene (NHC) compounds in organic, inorganic, and organometallic chemistry has been extended to another dimension. The immobilization of NHC compounds, undergoing continuous diversification, broadens their range of applications and leads to new solutions for challenges in catalytic and synthetic chemistry. This review intends to present a synthetic toolkit for the immobilization of NHC compounds, giving the reader an overview on synthetic techniques and strategies available in the literature. By individually summarizing and assessing the synthetic steps of the immobilization process, a comprehensive picture of the strategies and methodologies for the immobilization of NHC compounds is presented. Furthermore, the characterization of supported NHC compounds is discussed in detail in order to set up necessary criteria for an in-depth analysis of the immobilized derivatives. Finally, the catalytic applications of immobilized NHC compounds are briefly reviewed to illustrate the practical use of this technique for a broad variety of reaction types.

  4. Making eco-friendly transportation safer: developing computer-based simulations to assess of the impacts of bicycle accident prevention interventions on healthcare utilization.

    Science.gov (United States)

    Juhra, Christian; Borycki, Elizabeth M; Kushniruk, Andre W; Anderson, Jim; Anderson, Marilyn

    2011-01-01

    Computer-based modeling and simulations are becoming increasingly used for applications in health and safety. In this paper we describe a multi-phase project aimed at modeling bicycle accidents in Munster, Germany. The work involved a first phase of collecting empirical data on accident rates and severity. In the second phase a computer-based simulation model of bicycle accidents was created, using data from phase one to identify relevant parameters in the model. Finally, initial results from running the model are described that will be used to inform decision making regarding safety initiatives.

  5. Solid-supported synthesis: From pharmacologically relevant heterocycles to biologically active surfaces

    DEFF Research Database (Denmark)

    Komnatnyy, Vitaly V.

    for solid-phase synthesis, methods for on - and off-bead screening of combinatorial libraries and their applic ation to various biological targets. The first part of the thesis is dedicated to the development of methodology for the synthesis of structurally diverse heterocyclic scaffolds via N...... methods for the controlled organo-functionalization of titanium, one of the most prominent materials in medicinal device industry, have been suggested . Initial acidic and oxidative treatment s of the metal surface genera te reactive hydroxyl moieties , which are subsequently modified with synthetically...... versatile amine -containing reagents. Subsequent applications in antimicrobial peptide synthesis, metal -catalysis, release from the surface, and polymer grafti ng, are also presented....

  6. Bicycling-related accidents and factors contributing to injury

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Perez, L.M.; Wideberg, J.; Gonzalez Perez-Somarriba, B.

    2016-07-01

    Objective: This study was conducted to find the epidemiological characteristics of bicycling-related maxillofacial fractures in a defined population, and identify factors contributing to injury. Methodology: A prospective study was carried out involving patients presenting with maxillofacial fractures sustained in bicycling-related accidents. Results: Between 908 of all cycling accidents attending for medical treatment, 122 patients (13% of all cycling accidents) were admitted with facial fractures between 2007 and 2014. Male and female ratio was 2.6:1, and the mean age was 29.4 years (standard deviation: 12.8, range: 12-79 years). Causes of injury included collisions (63%) and accidental falls (37%). The fracture patterns seen were mandibular (49%), zygomatic (32%), orbital (13%), nasal (7%), maxillary (2%), and frontal (2%). Condylar fractures were the most common of the mandibular fractures (63%). The most frequently observed concomitant lesions were orthopedic injuries. Conclusions: Bicycling-related maxillofacial injuries are common and therefore important to identify in order to design a sustainable transport system and for units that provide assistance to traffic accident victims. Missed diagnosis or delayed treatment can lead to facial deformities and functional problems. Wearing protective helmets and the improvement of the helmets design is one aspect that would be of interest for the prevention of injuries. Keywords: Cycling; bicycle-related trauma; maxillofacial fractures; risk factors; helmets. (Author)

  7. preparation of bicyclic lactones using lewis acids catalyzed ene

    African Journals Online (AJOL)

    Administrator

    The synthesis of the cis-fused bicyclic lactones relies extensively on the Lewis acid ... having an allylic hydrogen (an"ene") and a compound containing an electron .... observed that the lithium enolate obtained from 3-methyl-2(5H)- furanone ...

  8. Nonfatal bicycle accident risk after an evening of alcohol consumption

    NARCIS (Netherlands)

    Verster, J.C.; van Herwijnen, J.; Volkerts, E.R.; Olivier, B.

    2009-01-01

    Introduction: After an evening of alcohol consumption, blood alcohol concentration (BAC) may reach intoxication levels above legal limits for operating a car or bicycle. In the Netherlands, legal limits for participating in traffic are 0.05% for experienced drivers and 0.02% for novice drivers. The

  9. Will a bicycle friendly policy make passenger travel more sustainably?

    DEFF Research Database (Denmark)

    Christensen, Linda; Jensen, Thomas Christian

    and bicycling. The study shows that instruments that improve the cyclists’ speed and increase the car drivers’ time consumption and costs will influence the competition conditions significantly. The total transfer potential will be between 12 and 16 % of the car trips in case of short tours, equivalent to 1...

  10. A strategic approach to [6,6]-bicyclic lactones

    DEFF Research Database (Denmark)

    Jepsen, Tue Heesgaard; Glibstrup, Emil; Crestey, Francois Louis Jean

    2017-01-01

    We report an effective synthetic protocol to access [6,6]-bicyclic lactone moieties through a regio- and stereoselective intramolecular Mizoroki–Heck cross-coupling reaction followed by a 6π-electrocyclization. This method enabled the first synthesis of the elusive CD fragment of the Erythrina...

  11. Synthesis and anticonvulsant activity of novel bicyclic acidic amino acids

    DEFF Research Database (Denmark)

    Conti, Paola; De Amici, Marco; Joppolo Di Ventimiglia, Samuele

    2003-01-01

    Bicyclic acidic amino acids (+/-)-6 and (+/-)-7, which are conformationally constrained homologues of glutamic acid, were prepared via a strategy based on a 1,3-dipolar cycloaddition. The new amino acids were tested toward ionotropic and metabotropic glutamate receptor subtypes; both of them...

  12. The effect of a yellow bicycle jacket on cyclist accidents

    DEFF Research Database (Denmark)

    Lahrmann, Harry; Madsen, Tanja Kidholm Osmann; Olesen, Anne Vingaard

    2018-01-01

    Highlights •A randomised controlled trial with 6793 cyclists shows a reduced accident risk due to a yellow bicycle jacket. •The test group had 47% fewer multiparty accidents with personal injury. •The test group had 55% fewer multiparty accidents against motorised vehicles....

  13. Efficiency of choice set generation methods for bicycle routes

    DEFF Research Database (Denmark)

    Halldórsdóttir, Katrín; Rieser-Schussler, Nadine; Axhausen, Kay W.

    2014-01-01

    for scenic routes, dedicated cycle lanes, and road type. Data consisted of 778 bicycle trips traced by GPS and carried out by 139 persons living in the Greater Copenhagen Area, in Denmark. Results suggest that both the breadth first search on link elimination and the doubly stochastic generation function...

  14. Utilizing the Bicycle for Non-Traditional Activities

    Science.gov (United States)

    Maina, Michael P.; Maina, Julie Schlegel; Sebek, Ludek; Hoffmanova, Jana; Kane, Jennifer Jackson

    2012-01-01

    This article examines the bicycle as not simply a means of transportation or as an exercise device, but rather as a vehicle for teambuilding and problem solving activities within a physical education curriculum. The activities described in this article focus on bike-centered initiatives that foster creative problem solving. They have universal…

  15. Costs and benefits of bicycling investments in Portland, Oregon.

    Science.gov (United States)

    Gotschi, Thomas

    2011-01-01

    Promoting bicycling has great potential to increase overall physical activity; however, significant uncertainty exists with regard to the amount and effectiveness of investment needed for infrastructure. The objective of this study is to assess how costs of Portland's past and planned investments in bicycling relate to health and other benefits. Costs of investment plans are compared with 2 types of monetized health benefits, health care cost savings and value of statistical life savings. Levels of bicycling are estimated using past trends, future mode share goals, and a traffic demand model. By 2040, investments in the range of $138 to $605 million will result in health care cost savings of $388 to $594 million, fuel savings of $143 to $218 million, and savings in value of statistical lives of $7 to $12 billion. The benefit-cost ratios for health care and fuel savings are between 3.8 and 1.2 to 1, and an order of magnitude larger when value of statistical lives is used. This first of its kind cost-benefit analysis of investments in bicycling in a US city shows that such efforts are cost-effective, even when only a limited selection of benefits is considered.

  16. Transition metal-catalyzed carbocyclization of nitrogen and oxygen-tethered 1,n-enynes and diynes: synthesis of five or six-membered heterocyclic compounds.

    Science.gov (United States)

    Zhang, Di-Han; Zhang, Zhen; Shi, Min

    2012-10-25

    Cycloisomerization of 1,n-enynes and diynes is a powerful method in organic synthesis to access heterocyclic compounds and has drawn increasing attention from organic chemists. In this paper, we attempted to summarize our recent results on the transition metal-catalyzed cycloisomerization to synthesize five or six-membered heterocyclic compounds using 1,n-enynes and diynes having a propargylic ester moiety. First, we will describe the synthesis of 2,3-disubstituted 3-pyrrolines via gold catalyzed cycloisomerization of 1,6-diynes. In addition, we will also disclose a novel silver catalyzed tandem 1,3-acyloxy migration/Mannich-type addition/elimination of the sulfonyl group of N-sulfonylhydrazone-propargylic esters to 5,6-dihydropyridazin-4-one derivatives. Furthermore, we will introduce three interesting examples of the synthesis of bicyclic compounds via titanium or rhodium catalyzed carbocyclization of enynes. In this context, we have presented that 1,n-enynes and diynes containing propargylic esters are highly reactive and useful starting materials for the cycloisomerization catalyzed by a transition metal catalyst.

  17. METHODS OF SYNTHESIS EIGHT-TELLURIUM-CONTAINING HETEROCYCLES WITH MORE HETEROATOMS

    Directory of Open Access Journals (Sweden)

    G. M. Abakarov

    2013-01-01

    Full Text Available In this article systematized and summarized data on the synthesis of neweight-embered tellurium-containing heterocycles and new preparative methods described above produce heterocyclic tellurium.

  18. Thiosemicarbazides in the synthesis of five- and six-membered heterocyclic compounds

    International Nuclear Information System (INIS)

    Gazieva, Galina A; Kravchenko, Angelina N

    2012-01-01

    Data on key chemical transformations of thiosemicarbazides resulting in heterocyclic compounds are generalized and described systematically. Methods for the synthesis of five- and six-membered heterocycles with two and three heteroatoms are considered. The bibliography includes 190 references.

  19. MICROBIAL DEGRADATION OF NITROGEN, OXYGEN AND SULFUR HETEROCYCLIC COMPOUNDS UNDER ANAEROBIC CONDITIONS: STUDIES WITH AQUIFER SAMPLES

    Science.gov (United States)

    The potential for anaerobic biodegradation of 12 heterocyclic model compounds was studied. Nine of the model compounds were biotransformed in aquifer slurries under sulfate-reducing or methanogenic conditions. The nitrogen and oxygen heterocyclic compounds were more susceptible t...

  20. Microwave-assisted synthesis of bio-active heterocycles in aqueous media

    KAUST Repository

    Polshettiwar, Vivek; Varma, Rajender S.

    2010-01-01

    Synthesis of bio-active heterocycles and fine chemicals in aqueous media are one of the best solutions for the development of green and sustainable protocols. To illustrate the advantages of aqueous MW chemistry in heterocycle synthesis

  1. Bicycle Trains, Cycling, and Physical Activity: A Pilot Cluster RCT.

    Science.gov (United States)

    Mendoza, Jason A; Haaland, Wren; Jacobs, Maya; Abbey-Lambertz, Mark; Miller, Josh; Salls, Deb; Todd, Winifred; Madding, Rachel; Ellis, Katherine; Kerr, Jacqueline

    2017-10-01

    Increasing children's cycling to school and physical activity are national health goals. The objective was to conduct an RCT of a bicycle train program to assess impact on students' school travel mode and moderate-to-vigorous physical activity (MVPA). Pilot cluster RCT with randomization at the school level and N=54 participants. Fourth-fifth graders from four public schools serving low-income families in Seattle, WA in 2014 with analyses in 2015-2016. All participants were provided and fitted with bicycles, safety equipment (helmets, locks, and lights), and a 2- to 3-hour bicycle safety course. The intervention was a bicycle train offered daily (i.e., students volunteered to cycle with study staff to and from school). Time 1 assessments occurred prior to randomization. Time 2 assessments occurred after 3-5 weeks of the intervention (i.e., during Weeks 4-6 of the intervention period). The primary outcome was the percentage of daily commutes to school by cycling measured by validated survey. MVPA, measured by accelerometry and GPS units and processed by machine learning algorithms, was a secondary outcome. For two separate adjusted repeated measures linear mixed effects models in which students (N=54) were nested within schools (N=4), intervention participants had: (1) an absolute increase in mean percentage of daily commutes by cycling of 44.9%, (95% CI=26.8, 63.0) and (2) an increase in mean MVPA of 21.6 minutes/day, (95% CI=8.7, 34.6) from Time 1 to Time 2 compared with controls. A pilot bicycle train intervention increased cycling to school and daily MVPA in the short term among diverse, inner-city elementary school students. The bicycle train intervention appears promising and warrants further experimental trials among large, diverse samples with longer follow-up. This study is registered at www.clinicaltrials.gov NCT02006186. Copyright © 2017 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  2. Chest Traumas due to Bicycle accident in Childhood

    Directory of Open Access Journals (Sweden)

    Ufuk Cobanoglu

    2011-09-01

    Full Text Available Aim:Childhood injuries are the leading cause of death in children and result in significant healthcare utilization. Trauma is the second most common cause of mortality in children aged 1-4 years and leading cause of death in children older than 4 years. Thoracic injury is the second most leading cause of death in traumatized children. Multisystemic injury is found in more than 50% of children with thoracic injuries most of which are secondary to blunt traumas. We planned this study to evaluate thorax trauma cases secondary to bicycle driving in childhood and to draw attention to the importance of the regulation of traffic rules, the education of bicycle drivers.Material and Methods:  A retrospective evaluation was performed in 17 pediatric patients admitted to the Department of Thoracic Surgery during 2006-2010 with a diagnosis of chest trauma due to bicycle driving. For every patient, a pediatric trauma score (PTS was calculated. Descriptive statistics were performed for PTS. Results; Eleven (64.70% cases were injured due to the tricycle accidents and six cases 6 (35.29% were injured due to the two-wheeled bicycle accidents. The most frequent thoracic pathologies included pulmonary contusion (41.2% and chest wall contusion (29.41%. Extrathoracic injuries were seen in 35.29%, the extremities (17.64% and abdomino pelvic (11.76% being the most commonly involved. Treatment consisted of symptomatic treatment in 12 patients (70.58%, tube thoracostomy in 2 patients (11.76%, and thoracotomy in 1 patient (5.9%. The morbidity was seen in 3 patients (17.64%. The mortality rate was 5.9% (n:1. The mean PTS of the cases who had additional system injuries were significantly worse than the cases who had isolated chest traumas Conclusions: The pediatric thorax has a greater cartilage content and incomplete ossification of the ribs. Due to the pliability of the pediatric rib cage and mediastinal mobility, significant intrathoracic injury may exist in the

  3. Heterocyclic amines in meat and meat products

    Directory of Open Access Journals (Sweden)

    Aliye BULGAN

    2013-06-01

    Full Text Available Heterocyclic amines (HA are the mutagenic/carcinogenic compounds which generate as a result of cooking of red meat, poultry meat and fish fillets at high temperatures. Up to 20 different HAs were detected and classified in the researches that conducted on these types of meats cooked at high temperatures. HAs are the products of Maillard reactions and the Strecker degredation of main precursors such as creatine/creatinine, aminoacid and the polysaccharides. Many physical and chemical factors effect the formation of HAs. Thus, it was reported by many researchers that utilizing coating and marination processes in addition to using natural and synthetic antioxidants and seasonings-plant extracts were effective on inhibiting/decreasing the formation of HAs. Additionally, boiling/steaming and microwave cooking methodologies were recommended instead of barbecuing, grilling or frying to inhibit/decrease the formation of HAs. The HAs formed in meat and meat products and the factors which have effects on the formation of HAs are presented in this review.

  4. Recent advances in the electrochemical construction of heterocycles

    Directory of Open Access Journals (Sweden)

    Robert Francke

    2014-12-01

    Full Text Available Due to the fact that the major portion of pharmaceuticals and agrochemicals contains heterocyclic units and since the overall number of commercially used heterocyclic compounds is steadily growing, heterocyclic chemistry remains in the focus of the synthetic community. Enormous efforts have been made in the last decades in order to render the production of such compounds more selective and efficient. However, most of the conventional methods for the construction of heterocyclic cores still involve the use of strong acids or bases, the operation at elevated temperatures and/or the use of expensive catalysts and reagents. In this regard, electrosynthesis can provide a milder and more environmentally benign alternative. In fact, numerous examples for the electrochemical construction of heterocycles have been reported in recent years. These cases demonstrate that ring formation can be achieved efficiently under ambient conditions without the use of additional reagents. In order to account for the recent developments in this field, a selection of representative reactions is presented and discussed in this review.

  5. Blue Chitin columns for the extraction of heterocyclic amines from urine samples

    DEFF Research Database (Denmark)

    Bang, J.; Frandsen, Henrik Lauritz; Skog, K.

    2004-01-01

    During normal cooking of meat, a class of mutagenic/carcinogenic compounds called heterocyclic amines is formed. Heterocyclic amines are rapidly absorbed and metabolised in the human body, and for estimation of the intake of heterocyclic amines, it is useful to determinate their levels in the uri...

  6. N-Heterocyclic Carbene-Catalyzed Olefination of Aldehydes with Vinyliodonium Salts To Generate α,β-Unsaturated Ketones.

    Science.gov (United States)

    Rajkiewicz, Adam A; Kalek, Marcin

    2018-04-06

    An organocatalyzed metal-free, direct olefination of aldehydes with vinyliodonium salts has been achieved by an N-heterocyclic carbene-promoted C-H bond activation. The reaction proceeds under very mild conditions, delivering a range of (hetero)aryl-vinyl ketones in good yields. The retention of the double bond configuration is uniformly observed, and the application of 2-methoxyphenyl auxiliary group in iodonium salts secures a complete selectivity of the vinyl transfer.

  7. BUGS at work : a bicycle user group guide

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This guide provides practical advice to cyclists on how start a Bicycle User Group (BUG) at their workplace. It offers tools to encourage employers to be proactive in improving facilities in support of cycle commuting. Several BUGs across Canada have worked towards getting better bicycle parking, lockers and shower facilities at their workplace. Other incentives include policies such as flexible work hours for cyclist commuters; casual dress on Friday; reimbursement for the subsidized cost of free parking provided by employers; and, use of a company car if needed for company business during the work day. The advantages to employers include: reduced health care costs because cyclists are physically fit; decreased absenteeism; increased productivity; reduced parking costs; lower company transportation bills; and, a greener corporate image. BUGs provide cycling information ranging from cycling maps to pamphlets and they raise cycle awareness. This guide includes cycling survey samples and examples of successful BUG activities across Canada. refs., tabs., figs.

  8. MIT-Skywalker: Evaluating comfort of bicycle/saddle seat.

    Science.gov (United States)

    Goncalves, Rogerio S; Hamilton, Taya; Daher, Ali R; Hirai, Hiroaki; Krebs, Hermano I

    2017-07-01

    The MIT-Skywalker is a robotic device developed for the rehabilitation of gait and balance after a neurological injury. This device has been designed based on the concept of a passive walker and provides three distinct training modes: discrete movement, rhythmic movement, and balance training. In this paper, we present our efforts to evaluate the comfort of a bicycle/saddle seat design for the system's novel actuated body weight support device. We employed different bicycle and saddle seats and evaluated comfort using objective and subjective measures. Here we will summarize the results obtained from a study of fifteen healthy subjects and one stroke patient that led to the selection of a saddle seat design for the MIT-Skywalker.

  9. Pseudoaneurysm of the Radial Artery After a Bicycle Fall.

    Science.gov (United States)

    Ratschiller, Thomas; Müller, Hannes; Schachner, Thomas; Zierer, Andreas

    2018-07-01

    We report a case of a 64-year-old man who developed a painful pulsatile mass in the distal forearm after a bicycle fall with fracture of the wrist. Ultrasonography confirmed a 2.5-cm large pseudoaneurysm of the radial artery. The patient underwent surgical exploration. The pseudoaneurysm was resected and the defect in the arterial wall was reconstructed with an autologous saphenous vein patch. We suggest that the double arterial supply of the hand should be preserved whenever possible.

  10. Harvesting energy from the counterbalancing (weaving) movement in bicycle riding.

    Science.gov (United States)

    Yang, Yoonseok; Yeo, Jeongjin; Priya, Shashank

    2012-01-01

    Bicycles are known to be rich source of kinetic energy, some of which is available for harvesting during speedy and balanced maneuvers by the user. A conventional dynamo attached to the rim can generate a large amount of output power at an expense of extra energy input from the user. However, when applying energy conversion technology to human powered equipments, it is important to minimize the increase in extra muscular activity and to maximize the efficiency of human movements. This study proposes a novel energy harvesting methodology that utilizes lateral oscillation of bicycle frame (weaving) caused by user weight shifting movements in order to increase the pedaling force in uphill riding or during quick speed-up. Based on the 3D motion analysis, we designed and implemented the prototype of an electro-dynamic energy harvester that can be mounted on the bicycle's handlebar to collect energy from the side-to-side movement. The harvester was found to generate substantial electric output power of 6.6 mW from normal road riding. It was able to generate power even during uphill riding which has never been shown with other approaches. Moreover, harvesting of energy from weaving motion seems to increase the economy of cycling by helping efficient usage of human power.

  11. The Comprehensive Benefit Evaluation of Take Shared Bicycles as Connecting to Public Transit

    Science.gov (United States)

    Zhang, J. Y.; Sun, H.; Li, P. F.; Li, C. C.

    2017-10-01

    Shared bicycles as an important way of connecting public transport, have few literature to evaluate its effectiveness.This paper taking Beijing city as an example, make anevaluationfor the six types of travel combinations which are commonly used by the citizens. The author selects four quantitative indicators: fuel consumption, economic cost, total time spent, and CO2 emission. And two qualitative indicators: degree of comfort and convenience. The relative efficiency of quantitative indicators is obtained by data envelopment analysis (DEA) and fuzzification and then take fuzzy synthetic evaluation with qualitative indicators.It was found that the choice of shared bicycles +subway+ shared bicycles and shared bicycles has good comprehensive benefits in medium distance travel. The findings also suggest that shared bicycles +subway+ shared bicycles is the best choice in the utilitarian trips. The conclusions not only provide suggestions for the travellers to select travel modes, but also can adjust the relevant factors to increase the proportion of green travel.

  12. Synthesis of heterocycles through transition-metal-catalyzed isomerization reactions

    DEFF Research Database (Denmark)

    Ishøy, Mette; Nielsen, Thomas Eiland

    2014-01-01

    of structurally complex and diverse heterocycles. In this Concept article, we attempt to cover this area of research through a selection of recent versatile examples. A sea of opportunities! Transition-metal-catalyzed isomerization of N- and O-allylic compounds provides a mild, selective and synthetically...... versatile method to form iminium and oxocarbenium ions. Given the number of reactions involving these highly electrophilic intermediates, this concept provides a sea of opportunities for heterocycle synthesis, (see scheme; Nu=nucleophile). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim....

  13. Inorganic heterocycles with two manganes or rhenium carbonyl units

    International Nuclear Information System (INIS)

    Kuellmer, V.; Vahrenkamp, H.

    1977-01-01

    From the reactive complexes [(CO) 4 M-E-Sn(CH 3 ) 3 ] 2 (M = Mn,Re; E = S,Se) with (CH 3 ) 2 PCl via the non-isolable four-membered ring intermediates [(CO) 4 M-E-P(CH 3 ) 2 ] 2 the six-membered heterocycles[-(CO) 4 M-P(CH 3 ) 2 -E-] 2 are formed. By use of (CH 3 ) 2 AsCl both the four-membered ring intermediates and the six-membered ring products can be isolated. The six-membered heterocycles can be opened by trimethylphosphine. (orig./HK) [de

  14. Synthesis and Characterization of a New Heterocyclic Azo Pigment

    International Nuclear Information System (INIS)

    Asniza, M.; Issam, A.M.; Khalil, H.P.S.A.

    2011-01-01

    A new heterocyclic coupling agent has been produced from the reaction of maleic anhydride and p-aminophenol, namely N-(4-hexahydrophenol)maleimide. The coupling agent underwent azo coupling reaction with aromatic amine, which is p-aminophenol to produce a new heterocyclic azo pigment. The pigment was then subjected to solubility, hiding power and light fastness test. Fourier Transform Infrared Spectroscopy (FTIR), Ultraviolet/ Visible (UV/Vis) Spectroscopy, and Nuclear Magnetic Resonance Spectroscopy ( 1 H-NMR, 13 C-NMR) were used to obtain the characteristics and structural features of the pigment. (author)

  15. Combinatorial synthesis of oxazol-thiazole bis-heterocyclic compounds.

    Science.gov (United States)

    Murru, Siva; Nefzi, Adel

    2014-01-13

    A combinatorial library of novel oxazol-thiazole bis-heterocycles was synthesized in good to excellent overall yields with high purity using a solution and solid-phase parallel synthesis approach. Oxazole amino acids, prepared from serine methyl ester and amino acids via coupling and cyclodehydration, were treated with Fmoc-NCS and α-haloketones for the parallel synthesis of diverse bis-heterocycles. Fmoc-isothiocyanate is used as a traceless reagent for thiazole formation. Oxazole diversity can be achieved by using variety of amino acids, whereas thiazole diversity is produced with various haloketones.

  16. Antioxidant evaluation of heterocyclic compounds by cytokinesis-block micronucleus assay.

    Science.gov (United States)

    Godevac, Dejan; Tesević, Vele; Vajs, Vlatka; Milosavljević, Slobodan; Stanković, Miroslava

    2013-03-01

    This article summarizes the results of using cytokinesis-block micronucleus (CBMN) assay to evaluate the antioxidant potential of heterocyclic compounds. Most studies were carried out with naturally occurring heterocyclic compounds such as plant polyphenols: flavonoids, xanthones, coumarins, and ellagitannins, or plant derived products (juices, extracts, supplements) rich in bioactive heterocyclic compounds. There are also some studies dealing with synthetic heterocyclic antioxidants. CBMN assay is an in vitro study that has been used to evaluate antioxidant and protective effects of heterocyclic compounds on induced chromosome aberration in human lymphocytes.

  17. Improvement of Freezing of Gait in Patients with Parkinson's Disease by Imagining Bicycling

    Directory of Open Access Journals (Sweden)

    Akio Kikuchi

    2014-03-01

    Full Text Available Freezing of gait (FOG is one of the factors that reduce the quality of life in patients with Parkinson's disease (PD. Imagining bicycling before gait start provided improvement in FOG in 2 PD patients. Imagining and mimicking bicycling after the initiation of gait allowed the rhythmic gait to continue without interruption. We suggest that imagining and mimicking bicycling, which are nonexternal cues, could serve as a helpful therapeutic approach for the intractable freezing and interruption of gait of PD patients.

  18. Positron annihilation lifetime studies of changes in free volume on some biorelevant nitrogen heterocyclic compounds and their S-glycosylation

    International Nuclear Information System (INIS)

    Mahmoud, K.R.; Khodair, A.I.; Shaban, S.Y.

    2015-01-01

    A series of N-heterocyclic compounds was investigated by positron annihilation lifetime spectroscopy as well as Doppler broadening of annihilation radiation (DBAR) at room temperature. The results showed that the formation probability and life time of ortho-positronium in this series are structure and electron-donation character dependent, and can give more information about the structure. The DBAR provides direct information about the change of core and valance electrons as well as the number of defect types present in these compounds. - Highlights: • N-heterocyclic compounds were studied by PALS and DBAR at room temperature. • These compounds contain thiohydantoins which have wide applications as anticarcinogenic, antiviral, human immunodeficiency virus (HIV) and antimicrobial activity. • The DBAR provides direct information about the change of core and valance electrons as well as the number of defect types present in these compounds.

  19. The Effect of Sharrows, Painted Bicycle Lanes and Physically Protected Paths on the Severity of Bicycle Injuries Caused by Motor Vehicles.

    Science.gov (United States)

    Wall, Stephen P; Lee, David C; Frangos, Spiros G; Sethi, Monica; Heyer, Jessica H; Ayoung-Chee, Patricia; DiMaggio, Charles J

    2016-01-01

    We conducted individual and ecologic analyses of prospectively collected data from 839 injured bicyclists who collided with motorized vehicles and presented to Bellevue Hospital, an urban Level-1 trauma center in New York City, from December 2008 to August 2014. Variables included demographics, scene information, rider behaviors, bicycle route availability, and whether the collision occurred before the road segment was converted to a bicycle route. We used negative binomial modeling to assess the risk of injury occurrence following bicycle path or lane implementation. We dichotomized U.S. National Trauma Data Bank Injury Severity Scores (ISS) into none/mild (0-8) versus moderate, severe, or critical (>8) and used adjusted multivariable logistic regression to model the association of ISS with collision proximity to sharrows (i.e., bicycle lanes designated for sharing with cars), painted bicycle lanes, or physically protected paths. Negative binomial modeling of monthly counts, while adjusting for pedestrian activity, revealed that physically protected paths were associated with 23% fewer injuries. Painted bicycle lanes reduced injury risk by nearly 90% (IDR 0.09, 95% CI 0.02-0.33). Holding all else equal, compared to no bicycle route, a bicycle injury nearby sharrows was nearly twice as likely to be moderate, severe, or critical (adjusted odds ratio 1.94; 95% confidence interval (CI) 0.91-4.15). Painted bicycle lanes and physically protected paths were 1.52 (95% CI 0.85-2.71) and 1.66 (95% CI 0.85-3.22) times as likely to be associated with more than mild injury respectively.

  20. The Effect of Sharrows, Painted Bicycle Lanes and Physically Protected Paths on the Severity of Bicycle Injuries Caused by Motor Vehicles

    Directory of Open Access Journals (Sweden)

    Stephen P. Wall

    2016-12-01

    Full Text Available We conducted individual and ecologic analyses of prospectively collected data from 839 injured bicyclists who collided with motorized vehicles and presented to Bellevue Hospital, an urban Level-1 trauma center in New York City, from December 2008 to August 2014. Variables included demographics, scene information, rider behaviors, bicycle route availability, and whether the collision occurred before the road segment was converted to a bicycle route. We used negative binomial modeling to assess the risk of injury occurrence following bicycle path or lane implementation. We dichotomized U.S. National Trauma Data Bank Injury Severity Scores (ISS into none/mild (0–8 versus moderate, severe, or critical (>8 and used adjusted multivariable logistic regression to model the association of ISS with collision proximity to sharrows (i.e., bicycle lanes designated for sharing with cars, painted bicycle lanes, or physically protected paths. Negative binomial modeling of monthly counts, while adjusting for pedestrian activity, revealed that physically protected paths were associated with 23% fewer injuries. Painted bicycle lanes reduced injury risk by nearly 90% (IDR 0.09, 95% CI 0.02–0.33. Holding all else equal, compared to no bicycle route, a bicycle injury nearby sharrows was nearly twice as likely to be moderate, severe, or critical (adjusted odds ratio 1.94; 95% confidence interval (CI 0.91–4.15. Painted bicycle lanes and physically protected paths were 1.52 (95% CI 0.85–2.71 and 1.66 (95% CI 0.85–3.22 times as likely to be associated with more than mild injury respectively.

  1. Bicycles, Birds, Bats and Balloons: New Applications for Algebra Classes.

    Science.gov (United States)

    Yoshiwara, Bruce; Yoshiwara, Kathy

    This collection of activities is intended to enhance the teaching of college algebra through the use of modeling. The problems use real data and involve the representation and interpretation of the data. The concepts addressed include rates of change, linear and quadratic regression, and functions. The collection consists of eight problems, four…

  2. Greener Alternatives to Expedient Synthesis of Heterocycles and Nanomaterial

    Science.gov (United States)

    A brief account of reactions involving microwave (MW) exposure of neat reactants or catalyzed by mineral support surfaces, such as alumina, silica, clay, or their ‘doped’ versions, for the rapid one-pot assembly of heterocyclic compounds [1] from in situ generated reactive interm...

  3. Greener Synthetic Alternatives to Heterocycles, Nanomaterials and Nanocomposites

    Science.gov (United States)

    Microwave (MW) expedited reaction of neat reactants or catalyzed by mineral support surfaces, such as alumina, silica, clay, or their ‘doped’ versions, for the rapid one-pot assembly of heterocyclic compounds from in situ generated reactive intermediates via enamines or using hyp...

  4. Transformation of saturated nitrogen-containing heterocyclic compounds by microorganisms.

    Science.gov (United States)

    Parshikov, Igor A; Silva, Eliane O; Furtado, Niege A J C

    2014-02-01

    The saturated nitrogen-containing heterocyclic compounds include many drugs and compounds that may be used as synthons for the synthesis of other pharmacologically active substances. The need for new derivatives of saturated nitrogen-containing heterocycles for organic synthesis, biotechnology and the pharmaceutical industry, including optically active derivatives, has increased interest in microbial synthesis. This review provides an overview of microbial technologies that can be valuable to produce new derivatives of saturated nitrogen-containing heterocycles, including hydroxylated derivatives. The chemo-, regio- and enantioselectivity of microbial processes can be indispensable for the synthesis of new compounds. Microbial processes carried out with fungi, including Beauveria bassiana, Cunninghamella verticillata, Penicillium simplicissimum, Aspergillus niger and Saccharomyces cerevisiae, and bacteria, including Pseudomonas sp., Sphingomonas sp. and Rhodococcus erythropolis, biotransform many substrates efficiently. Among the biological activities of saturated nitrogen-containing heterocyclic compounds are antimicrobial, antitumor, antihypertensive and anti-HIV activities; some derivatives are effective for the treatment and prevention of malaria and trypanosomiasis, and others are potent glycosidase inhibitors.

  5. Toxicity of six heterocyclic nitrogen compounds to Daphnia pulex

    Science.gov (United States)

    Perry, Cynthia M.; Smith, Stephen B.

    1988-01-01

    We determined the relative toxicities to the aquatic crustacean Daphniz pulex of six heterocyclic nitrogen compunds. These compounds were selected because they were detected in lake trout or walleyes and were commercially available. Stress to the daphnid populations may affect forage fish populations that depend either directly or indirectly on zooplankton as a food source in the Great Lakes.

  6. GREENER SYNTHESIS OF HETEROCYCLIC COMPOUNDS USING MICROWAVE IRRADIATION

    Science.gov (United States)

    An introduction of our interest in the microwave-assisted greener synthesis of a variety of heterocyclic compounds will be presented. It involves microwave (MW) exposure of neat reactants (undiluted) catalyzed by the surfaces of recyclable mineral supports, such as alumina, sili...

  7. Synthesis and properties of heterocyclic type I photoinitiators

    International Nuclear Information System (INIS)

    Liska, R.; Knaus, S.; Wendrinsky, J.

    1999-01-01

    The synthesis and properties of a series of new heterocyclic hydroxyalkylphenone-analogous photoinitiators (PIs) is described. The PIs are obtained by reaction of aromatic organolithium compounds with nitriles or by Friedel-Craft's-acylation. Preliminary photocalorimetric tests and UV absorption data are included

  8. Greener and Expeditious Synthesis of Bioactive Heterocycles using Microwave Irradiation

    Science.gov (United States)

    The utilization of green chemistry techniques is dramatically reducing chemical waste and reaction times as has recently been proven in several organic syntheses and chemical transformations. To illustrate these advantages in the synthesis of bio-active heterocycles, we have stud...

  9. 40 CFR 721.10003 - Manganese heterocyclic tetraamine complex (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Manganese heterocyclic tetraamine complex (generic). 721.10003 Section 721.10003 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... section. (2) The significant new uses are: (i) Industrial, commercial, and consumer activities...

  10. In Situ Cyclization of Native Proteins: Structure-Based Design of a Bicyclic Enzyme.

    Science.gov (United States)

    Pelay-Gimeno, Marta; Bange, Tanja; Hennig, Sven; Grossmann, Tom N

    2018-05-30

    Increased tolerance of enzymes towards thermal and chemical stress is required for many applications and can be achieved by macrocyclization of the enzyme resulting in the stabilizing of its tertiary structure. So far, macrocyclization approaches utilize a very limited structural diversity which complicates the design process. Here, we report an approach that enables cyclization via the installation of modular crosslinks into native proteins composed entirely of proteinogenic amino acids. Our stabilization procedure involves the introduction of three surface exposed cysteines which are reacted with a triselectrophile resulting in the in situ cylization of the protein (INCYPRO). A bicyclic version of Sortase A was designed exhibiting increased tolerance towards thermal as well as chemical denaturation, and proved efficient in protein labeling under denaturing conditions. In addition, we applied INCYPRO to the KIX domain resulting in up to 24 °C increased thermal stability. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Injury rates from walking, gardening, weightlifting, outdoor bicycling, and aerobics.

    Science.gov (United States)

    Powell, K E; Heath, G W; Kresnow, M J; Sacks, J J; Branche, C M

    1998-08-01

    The objective of this survey was to estimate the frequency of injuries associated with five commonly performed moderately intense activities: walking for exercise, gardening and yard work, weightlifting, aerobic dance, and outdoor bicycling. National estimates were derived from weighted responses of over 5,000 individuals contacted between April 28 and September 18, 1994, via random-digit dialing of U.S. residential telephone numbers. Self-reported participation in these five activities in the late spring and summer of 1994 was common, ranging from an estimated 14.5 +/- 1.2% of the population for aerobics (nearly 30 million people) to 73.0 +/- 1.5% for walking (about 138 million people). Among participants, the activity-specific 30-d prevalence of injury ranged from 0.9 +- 0.5% for outdoor bicycle riding to 2.4 +- 1.3% for weightlifting. The estimated number in the 30 d of people injured in the 30 d before their interview ranged from 330,000 for outdoor bicycle riding to 2.1 million for gardening or yard work. Incidence rates for injury causing reduced participation in activity were 1.1 +/- 0.5x100 participantsx30 d for walking, 1.1 +/- 0.4 for gardening, and 3.3 +/- 1.9 for weightlifting. During walking and gardening, men and women were equally likely to be injured, but younger people (18-44 yr) were more likely to be injured than older people (45 + yr). Injury rates were low, yet large numbers of people were injured because participation rates were high. Most injuries were minor, but injuries may reduce participation in these otherwise beneficial activities. Additional studies to confirm the magnitude of the problem, to identify modifiable risk factors, and to recommend methods to reduce the frequency of such injuries are needed.

  12. Consumers’ preferences for “bicycle poultry” in Benin

    DEFF Research Database (Denmark)

    Sodjinou, Epiphane; Henningsen, Arne; Koudande, Delphin O.

    2015-01-01

    Village poultry, also termed "bicycle poultry," is produced in scavenging farming systems and is a chewy meat with a low fat content, and constitutes an important source of meat in many African countries. This study investigates consumers’ preferences regarding the physical traits of these birds...... (notably chickens, ducks and guinea fowl) in the Republic of Benin. For this purpose, we applied the hedonic price method on field data collected from retailers in four urban and five rural markets. We found that meatier drake and meatier guinea fowl with white plumage are preferred by consumers who...

  13. Efficiency of Choice Set Generation Methods for Bicycle Routes

    DEFF Research Database (Denmark)

    Halldórsdóttir, Katrín; Rieser-Schüssler, Nadine; W. Axhausen, Kay

    behaviour, observed choices and alternatives composing the choice set of each cyclist are necessary. However, generating the alternative choice sets can prove challenging. This paper analyses the efficiency of various choice set generation methods for bicycle routes in order to contribute to our...... travelling information with GPS loggers, compared to self-reported RP data, is more accurate geographic locations and routes. Also, the GPS traces give more reliable information on times and prevent trip underreporting, and it is possible to collect information on many trips by the same person without...

  14. Injuries to Cyclists due to a Dog-Bicycle Interaction.

    Science.gov (United States)

    Loder, Randall T; Yaacoub, Alan P

    2018-05-01

     Both dogs and bicycles are common in our society and thus a dog-bicycle interaction resulting in an injury to a cyclist is possible. It was the purpose of this study to investigate such injuries.  The National Electronic Injury Surveillance System (NEISS) data for the 10-year period from 2006 through 2015 associated with bicycles were accessed. Injuries involving dogs were identified and the mechanism of injury determined. Due to the stratified and weighted nature of the NEISS data, statistical analyses were performed with SUDAAN 10 software (RTI International, Research Triangle Park, North Carolina, United States). A p  dogs were involved in 35,254 (0.67%) cases. The average age for those involved with a dog was 33.2 years and it was 25.5 years for those in which dogs were not involved. There were more females in the dog group (34.1 vs. 27.6%). Dog involvement increased from ages 0 to 14 years, then decreased until the age of 20 years and then progressively increased. Dog-associated injuries most frequently occurred away from home, involved the knee and distal lower extremity, 49.1% sustaining dog bites. Dog bites were more common in younger individuals. Four injury mechanisms (chased by a dog, hit/collided with a dog, swerved/tried to avoid a dog or riding with a dog) accounted for 97.5% of the injuries. Those chased by a dog were younger, more commonly released from the emergency department, had an injury involving the lower extremity and frequently sustained a bite. The most severe injuries were in those who swerved/tried to avoid a dog or hit a dog.  Approximately 1% of injuries to bicyclists are associated with dogs; one-half sustained a bite. Potential/proposed prevention strategies could be educational materials regarding bicycles and dogs to owners, dog restraint, student/parent education and educational materials in waiting rooms of veterinarians, paediatricians, family practice physicians and emergency rooms. Schattauer GmbH Stuttgart.

  15. Insight into eukaryotic topoisomerase II-inhibiting fused heterocyclic compounds in human cancer cell lines by molecular docking.

    Science.gov (United States)

    Taskin, T; Yilmaz, S; Yildiz, I; Yalcin, I; Aki, E

    2012-01-01

    Etoposide is effective as an anti-tumour drug by inhibiting eukaryotic DNA topoisomerase II via establishing a covalent complex with DNA. Unfortunately, its wide therapeutic application is often hindered by multidrug resistance (MDR), low water solubility and toxicity. In our previous study, new derivatives of benzoxazoles, benzimidazoles and related fused heterocyclic compounds, which exhibited significant eukaryotic DNA topoisomerase II inhibitory activity, were synthesized and exhibited better inhibitory activity compared with the drug etoposide itself. To expose the binding interactions between the eukaryotic topoisomerase II and the active heterocyclic compounds, docking studies were performed, using the software Discovery Studio 2.1, based on the crystal structure of the Topo IIA-bound G-segment DNA (PDB ID: 2RGR). The research was conducted on a selected set of 31 fused heterocyclic compounds with variation in structure and activity. The structural analyses indicate coordinate and hydrogen bonding interactions, van der Waals interactions and hydrophobic interactions between ligands and the protein, as Topo IIA-bound G-segment DNA are responsible for the preference of inhibition and potency. Collectively, the results demonstrate that the compounds 1a, 1c, 3b, 3c, 3e and 4a are significant anti-tumour drug candidates that should be further studied.

  16. Reduction of the Work Function of Gold by N-Heterocyclic Carbenes

    KAUST Repository

    Kim, Hye Kyung

    2017-04-12

    N-Heterocyclic carbenes (NHCs) bind strongly to gold and other metals. This work experimentally probes the effect of NHCs on the work function (WF) of gold for the first time, theoretically analyzes the origin of this effect, and examines the effectiveness of NHC-modified gold as an electron-injecting electrode. UV photoelectron spectroscopy shows the WF of planar gold is reduced by nearly 2 eV to values of 3.3–3.5 eV. This effect is seen for NHCs with various heterocyclic cores, and with either small or large N,N′-substituents. DFT calculations indicate the WF reduction results from both the interface dipole formed between the NHC and the gold and from the NHC molecular dipole. For N,N′-diisopropyl-NHCs, an important contributor to the former is charge transfer associated with coordination of the carbene carbon atom to gold. In contrast, the carbene carbon of N,N′-2,6-diisopropylphenyl-NHCs is not covalently bound to gold, resulting in a lower interface dipole; however, a larger molecular dipole partially compensates for this. Single-layer C60 diodes with NHC-modified gold as the bottom electrode demonstrate high rectification ratios and show that these electrodes can act as effective electron-injecting contacts, suggesting they may be useful for a variety of materials applications.

  17. Reduction of the Work Function of Gold by N-Heterocyclic Carbenes

    KAUST Repository

    Kim, Hye Kyung; Hyla, Alexander; Winget, Paul; Li, Hong; Wyss, Chelsea M.; Jordan, Abraham J.; Larrain, Felipe A.; Sadighi, Joseph P.; Fuentes-Hernandez, Canek; Kippelen, Bernard; Bredas, Jean-Luc; Barlow, Stephen; Marder, Seth R.

    2017-01-01

    N-Heterocyclic carbenes (NHCs) bind strongly to gold and other metals. This work experimentally probes the effect of NHCs on the work function (WF) of gold for the first time, theoretically analyzes the origin of this effect, and examines the effectiveness of NHC-modified gold as an electron-injecting electrode. UV photoelectron spectroscopy shows the WF of planar gold is reduced by nearly 2 eV to values of 3.3–3.5 eV. This effect is seen for NHCs with various heterocyclic cores, and with either small or large N,N′-substituents. DFT calculations indicate the WF reduction results from both the interface dipole formed between the NHC and the gold and from the NHC molecular dipole. For N,N′-diisopropyl-NHCs, an important contributor to the former is charge transfer associated with coordination of the carbene carbon atom to gold. In contrast, the carbene carbon of N,N′-2,6-diisopropylphenyl-NHCs is not covalently bound to gold, resulting in a lower interface dipole; however, a larger molecular dipole partially compensates for this. Single-layer C60 diodes with NHC-modified gold as the bottom electrode demonstrate high rectification ratios and show that these electrodes can act as effective electron-injecting contacts, suggesting they may be useful for a variety of materials applications.

  18. The pH-influenced PET processes between pyronine and different heterocycles.

    Science.gov (United States)

    Yang, Ling; Niu, Jin-Yun; Sun, Ru; Xu, Yu-Jie; Ge, Jian-Feng

    2017-10-11

    The OFF-ON and ON-OFF type pH probes based on rosamine were designed by using the relative electron densities between pyronine and various linked heterocycles. Probe 1a with an indole-pyronine skeleton gave an OFF-ON pH response (pK a = 1.41) with decreasing pH, and the relative fluorescence intensity increased 15-fold, while probe 1b with an imidazole-pyronine skeleton did not give an ON-OFF response to different pH values. When pyronine was connected with a quinolinyl group, i.e., probes 1c-d, the red emission (around 575-800 nm) gave a monotonous ON-OFF pH response (pK a = 3.26 and 2.62, respectively) with decreasing pH. The relative fluorescence intensities decreased 263- and 46-fold, respectively. Changes in the electron donating abilities of the nitrogen containing heterocycles were used to explain variations in PET processes within the probes, and their pH-dependent PET mechanisms were verified using time-dependent density functional theory calculations. Confocal fluorescence imaging was also used to evaluate the potential biomedical application of probes 1a-d. Ultimately, probe 1d with an appropriate pK a value and good biocompatibility showed lysosome targeting ability.

  19. How the Netherlands became a bicycle nation : users, firms and intermediaries, 1860-1940

    NARCIS (Netherlands)

    Tjong Tjin Tai, S.E.; Veraart, F.C.A.; Davids, M.

    2015-01-01

    In 1925, the Netherlands was a country of cyclists and cycle producers, as all classes cycled and almost all cycles were produced domestically. The bicycle was not a Dutch invention and the country had an open economy, and this raises the question ‘how did the Netherlands become a bicycle nation?’

  20. Children's Perception of Gap Affordances: Bicycling Across Traffic-Filled Intersections in an Immersive Virtual Environment

    Science.gov (United States)

    Plumert, Jodie M.; Kearney, Joseph K.; Cremer, James F.

    2004-01-01

    This study examined gap choices and crossing behavior in children and adults using an immersive, interactive bicycling simulator. Ten- and 12-year-olds and adults rode a bicycle mounted on a stationary trainer through a virtual environment consisting of a street with 6 intersections. Participants faced continuous cross traffic traveling at 25mph…

  1. The different ways to get on and off a bicycle for young and old

    NARCIS (Netherlands)

    Dubbeldam, R.; Baten, C. T.M.; Straathof, P.T.C.; Buurke, J. H.; Rietman, J. S.

    2017-01-01

    In the Netherlands, each year 12,000 older cyclists require medical attention due to a single-bicycle accident where no other party is directly involved. Most of these accidents occur at low cycling velocities and 20% occur during (dis)mounting the bicycle. Little is known about the strategies and

  2. Getting Bicycles on Trains - Inter-modal Transport Developments in Denmark

    DEFF Research Database (Denmark)

    Jørgensen, Ulrik; Pedersen, Bjørn Brix

    2001-01-01

    The combined use of bicycles and trains has been favored in contemporary public transport policies in Denmark. Although bicycling has played a major role in Danish personal transportation in more than hundred years, the attitude from public transport authorities towards supporting bicyclists has ...... varied quite a lot....

  3. The unexpected stable market share of the bicycle in The Netherlands

    NARCIS (Netherlands)

    Van Goeverden, C.D.; Van Arem, B.; Godefrooij, T.

    2013-01-01

    In the Netherlands, the share of the bicycle as the main mode in all person trips has been highly constant in the past three decades (about 27%). A constant share is remarkable because a number of developments in this period were unfavourable for bicycle use, like ageing of the population, growing

  4. A summary of design, policies and operational characteristics for shared bicycle/bus lanes.

    Science.gov (United States)

    2012-07-01

    This report contains the results of an investigation of the design and operation of shared bicycle/bus lanes in municipalities in the United States and other countries. These lanes are designated for use by public transit buses, bicycles, and usually...

  5. Bicycle Design : A different approach to improving on the world human powered speed records

    NARCIS (Netherlands)

    Epema, H.K.; Van den Brand, S.; Gregoor, W.; Kooijman, J.D.G.; Pereboom, H.P.; Wielemaker, D.C.; Van der Zweep, C.J.

    2012-01-01

    The current International Human Powered Vehicle Association world records for faired bicycles stand at 133.284km/h for the 200m flying start speed record and 91.562 km for the hour record. Traditionally the recumbent bicycles that have been developed for breaking one of either of these records have

  6. On the influence of tyre and structural properties on the stability of bicycles

    Science.gov (United States)

    Doria, Alberto; Roa Melo, Sergio Daniel

    2018-06-01

    In recent years the Whipple Carvallo Bicycle Model has been extended to analyse high speed stability of bicycles. Various researchers have developed models taking into account the effects of front frame compliance and tyre properties, nonetheless, a systematic analysis has not been yet carried out. This paper aims at analysing parametrically the influence of front frame compliance and tyre properties on the open loop stability of bicycles. Some indexes based on the eigenvalues of the dynamic system are defined to evaluate quantitatively bicycle stability. The parametric analysis is carried out with a factorial design approach to determine the most influential parameters. A commuting and a racing bicycle are considered and numerical results show different effects of the various parameters on each bicycle. In the commuting bicycle, the tyre properties have greater influence than front frame compliance, and the weave mode has the main effect on stability. Conversely, in the racing bicycle, the front frame compliance parameters have greater influence than tyre properties, and the wobble mode has the main effect on stability.

  7. Comparison of five bicycle facility designs in signalized intersections using traffic conflict studies

    DEFF Research Database (Denmark)

    Madsen, Tanja Kidholm Osmann; Lahrmann, Harry Spaabæk

    2017-01-01

    Highlights •Traffic conflict study comparing cyclists’ relative risk for five bicycle layouts. •Watchdog video analysis software applied to reduce video data. •Video analysis software necessary to conduct larger conflict studies. •Recessed bicycle track seems to provide the highest safety level...

  8. Does pedalling on a recumbent bicycle influence the cyclist’s steering behaviour?

    NARCIS (Netherlands)

    Boon, K.M.; Klap, P.; Van Lanen, J.A.; Letsoin, G.J.; Jansen, A.J.

    2014-01-01

    The paper presents the answer to the question how pedalling on a specific recumbent bicycle, such as the VeloX3, influences a cyclist’s ability to steer the bicycle. The research aims to find the correlation between pedalling and the undesired steering movements it creates. To test this assumption a

  9. Evaluating the Interference of Bicycle Traffic on Vehicle Operation on Urban Streets with Bike Lanes

    Directory of Open Access Journals (Sweden)

    Ziyuan Pu

    2017-01-01

    Full Text Available Many urban streets are designed with on-street bike lanes to provide right-of-way for bicycle traffic. However, when bicycle flow is large, extensive passing maneuvers could occupy vehicle lanes and thus cause interferences to vehicle traffic. The primary objective of this study is to evaluate how bicycle traffic affects vehicle operation on urban streets with bike lanes. Data were collected on six street segments in Nanjing, China. The cumulative curves were constructed to extract traffic flow information including individual bicycle and vehicle speeds and aggregated traffic parameters such as flow and density. The results showed that as bicycle density on bike lanes continuously increases faster bicycles may run into vehicle lanes causing considerable reductions in vehicle speeds. A generalized linear model was estimated to predict the vehicle delay. Results showed that vehicle delay increases as bicycle flow and vehicle flow increase. Number of vehicle lanes and width of bike lane also have significant impact on vehicle delay. Findings of the study are helpful to regions around the world in bike infrastructure design in order to improve operations of both bicycles and vehicles.

  10. Skeletal diversification via heteroatom linkage control: preparation of bicyclic and spirocyclic scaffolds from N-substituted homopropargyl alcohols.

    Science.gov (United States)

    Painter, Thomas O; Bunn, Jonathon R; Schoenen, Frank J; Douglas, Justin T; Day, Victor W; Santini, Conrad

    2013-04-19

    The discovery and application of a new branching pathway synthesis strategy that rapidly produces skeletally diverse scaffolds is described. Two different scaffold types, one a bicyclic iodo-vinylidene tertiary amine/tertiary alcohol and the other, a spirocyclic 3-furanone, are each obtained using a two-step sequence featuring a common first step. Both scaffold types lead to intermediates that can be orthogonally diversified using the same final components. One of the scaffold types was obtained in sufficiently high yield that it was immediately used to produce a 97-compound library.

  11. The relationship between bicycle commuting and perceived stress: a cross-sectional study.

    Science.gov (United States)

    Avila-Palencia, Ione; de Nazelle, Audrey; Cole-Hunter, Tom; Donaire-Gonzalez, David; Jerrett, Michael; Rodriguez, Daniel A; Nieuwenhuijsen, Mark J

    2017-06-23

    Active commuting - walking and bicycling for travel to and/or from work or educational addresses - may facilitate daily, routine physical activity. Several studies have investigated the relationship between active commuting and commuting stress; however, there are no studies examining the relationship between solely bicycle commuting and perceived stress, or studies that account for environmental determinants of bicycle commuting and stress. The current study evaluated the relationship between bicycle commuting, among working or studying adults in a dense urban setting, and perceived stress. A cross-sectional study was performed with 788 adults who regularly travelled to work or study locations (excluding those who only commuted on foot) in Barcelona, Spain. Participants responded to a comprehensive telephone survey concerning their travel behaviour from June 2011 through to May 2012. Participants were categorised as either bicycle commuters or non-bicycle commuters, and (based on the Perceived Stress Scale, PSS-4) as either stressed or non-stressed. Multivariate Poisson regression with robust variance models of stress status based on exposures with bicycle commuting were estimated and adjusted for potential confounders. Bicycle commuters had significantly lower risk of being stressed than non-bicycle commuters (Relative Risk; RR (95% CI)=0.73 (0.60 to 0.89), p=0.001). Bicycle commuters who bicycled 4 days per week (RR (95% CI)=0.42 (0.24 to 0.73), p=0.002) and those who bicycled 5 or more days per week (RR (95% CI)=0.57 (0.42 to 0.77), pstressed than those who bicycled less than 4 days. This relationship remained statistically significant after adjusting for individual and environmental confounders and when using different cut-offs of perceived stress. Stress reduction may be an important consequence of routine bicycle use and should be considered by decision makers as another potential benefit of its promotion. © Article author(s) (or their employer

  12. The spatio-temporal Development of Copenhagen's bicycle infrastructure 1912-2013

    DEFF Research Database (Denmark)

    Carstensen, Trine Agervig; Olafsson, Anton Stahl; Bech, Nynne Marie

    2015-01-01

    Cycling plays an important role in low-carbon transitions. Around the globe, cities are constructing bicycle infrastructure. The city of Copenhagen has a bicycle-friendly infrastructure celebrated for its fine-meshed network. This study documents the spatio-temporal development of Copenhagen......’s bicycle infrastructure and explores how the development corresponds to other processes of urban transformation. The study builds on historical maps of bicycle infrastructure that are digitised into geographical information, which allows for a comprehensive analysis of the formation of the network....... In search for identifying drivers, the study analyses the city’s spatial growth pattern, migration pattern, development of road network and changes in the transport culture. Analyses reveal that the bicycle infrastructure expanded at a relatively constant pace during distinct periods of urban transformation...

  13. Vision-Based Bicycle Detection Using Multiscale Block Local Binary Pattern

    Directory of Open Access Journals (Sweden)

    Hongyu Hu

    2014-01-01

    Full Text Available Bicycle traffic has heavy proportion among all travel modes in some developing countries, which is crucial for urban traffic control and management as well as facility design. This paper proposes a real-time multiple bicycle detection algorithm based on video. At first, an effective feature called multiscale block local binary pattern (MBLBP is extracted for representing the moving object, which is a well-classified feature to distinguish between bicycles and nonbicycles; then, a cascaded bicycle classifier trained by AdaBoost algorithm is proposed, which has a good computation efficiency. Finally, the method is tested with video sequence captured from the real-world traffic scenario. The bicycles in the test scenario are successfully detected.

  14. Environmental Risk Factors influencing Bicycle Theft: A Spatial Analysis in London, UK.

    Directory of Open Access Journals (Sweden)

    Lucy Waruguru Mburu

    Full Text Available Urban authorities are continuously drawing up policies to promote cycling among commuters. However, these initiatives are counterproductive for the targeted objectives because they increase opportunities for bicycle theft. This paper explores Inner London as a case study to address place-specific risk factors for bicycle theft at the street-segment level while controlling for seasonal variation. The presence of certain public amenities (e.g., bicycle stands, railway stations, pawnshops was evaluated against locations of bicycle theft between 2013 and 2016 and risk effects were estimated using negative binomial regression models. Results showed that a greater level of risk stemmed from land-use facilities than from area-based socioeconomic status. The presence of facilities such as train stations, vacant houses, pawnbrokers and payday lenders increased bicycle theft, but no evidence was found that linked police stations with crime levels. The findings have significant implications for urban crime prevention with respect to non-residential land use.

  15. Environmental Risk Factors influencing Bicycle Theft: A Spatial Analysis in London, UK.

    Science.gov (United States)

    Mburu, Lucy Waruguru; Helbich, Marco

    2016-01-01

    Urban authorities are continuously drawing up policies to promote cycling among commuters. However, these initiatives are counterproductive for the targeted objectives because they increase opportunities for bicycle theft. This paper explores Inner London as a case study to address place-specific risk factors for bicycle theft at the street-segment level while controlling for seasonal variation. The presence of certain public amenities (e.g., bicycle stands, railway stations, pawnshops) was evaluated against locations of bicycle theft between 2013 and 2016 and risk effects were estimated using negative binomial regression models. Results showed that a greater level of risk stemmed from land-use facilities than from area-based socioeconomic status. The presence of facilities such as train stations, vacant houses, pawnbrokers and payday lenders increased bicycle theft, but no evidence was found that linked police stations with crime levels. The findings have significant implications for urban crime prevention with respect to non-residential land use.

  16. A multi-modal network approach to model public transport accessibility impacts of bicycle-train integration policies

    NARCIS (Netherlands)

    Geurs, Karst Teunis; La Paix Puello, Lissy Cesarina; van Weperen, Sander

    2016-01-01

    In the Netherlands, the bicycle plays an important in station access and, to a lesser extent, in station egress. There is however fairly little knowledge in the potential effects of bicycle-train integration policies. The aim of this paper is to examine the impacts of bicycle-train integration

  17. Hydrolysis of strained bridgehead bicyclic vinyl ethers and sulfides

    International Nuclear Information System (INIS)

    Chwang, W.K.; Kresge, A.J.; Wiseman, J.R.

    1979-01-01

    Rates of hydrolysis of the bridgehead bicyclic vinyl ether 9-oxabicyclo[3.3.1]non-1-ene(6) and its vinyl sulfide counterpart 9-thiabicyclo[3.3.1]non-1-ene(7), catalyzed by the hydronium ion, were measured in H 2 O and in D 2 O solution. These data give isotope effects, k/sub H//k/sub D/ = 2.4 and 1.9 respectively, which show that these reactions occur by the normal, rate-determining carbon protonation, mechanism. The vinyl ether 6 is less reactive than its olefin analogue, bicyclo[3.3.1]non-1-ene (relative rate 1:1/1400), as may have been expected for a constrained bicyclic system such as this, where stabilization of the bridgehead carbocation intermediate by conjugation with oxygen is severely impaired. The vinyl sulfide 7, however, is even less reactive than the vinyl ether (relative rates 1:1/140); this is a remarkable result in view of the fact that conjugation between the sulfur atom and the cationic center is presumably also strongly inhibited. 1 figure, 3 tables

  18. Harvesting Energy from the Counterbalancing (Weaving Movement in Bicycle Riding

    Directory of Open Access Journals (Sweden)

    Shashank Priya

    2012-07-01

    Full Text Available Bicycles are known to be rich source of kinetic energy, some of which is available for harvesting during speedy and balanced maneuvers by the user. A conventional dynamo attached to the rim can generate a large amount of output power at an expense of extra energy input from the user. However, when applying energy conversion technology to human powered equipments, it is important to minimize the increase in extra muscular activity and to maximize the efficiency of human movements. This study proposes a novel energy harvesting methodology that utilizes lateral oscillation of bicycle frame (weaving caused by user weight shifting movements in order to increase the pedaling force in uphill riding or during quick speed-up. Based on the 3D motion analysis, we designed and implemented the prototype of an electro-dynamic energy harvester that can be mounted on the bicycle’s handlebar to collect energy from the side-to-side movement. The harvester was found to generate substantial electric output power of 6.6 mW from normal road riding. It was able to generate power even during uphill riding which has never been shown with other approaches. Moreover, harvesting of energy from weaving motion seems to increase the economy of cycling by helping efficient usage of human power.

  19. Privileged scaffolds or promiscuous binders: a glance of pyrrolo[2,1-f][1,2,4]triazines and related bridgehead nitrogen heterocycles in medicinal chemistry.

    Science.gov (United States)

    Song, Yu'ning; Zhan, Peng; Zhang, Qingzhu; Liu, Xinyong

    2013-01-01

    Pyrrolo[2,1-f][1,2,4]triazine template, a unique bridgehead nitrogen heterocycle, certainly deserves the title of "privileged scaffold" in the drug discovery field because of the versatility and potential to yield derivatives with a wide range of biological activities, such as anti-anaplastic lymphoma kinase (ALK), Janus kinase 2 (JAK2), VEGFR-2, EGFR and/or HER2, Met kinase, p38α mitogen-activated protein (MAP) kinase and insulin-like growth factor receptor (IGF-1R) kinase activities, etc. These different biological properties of pyrrolo[2,1-f][1,2,4]triazine derivatives have motivated new studies in searching for novel derivatives with improved activity and also other applications in pharmaceutical field. However, no systematic review is available in the literature on the pyrrolo[2,1- f][1,2,4]triazine derivatives concerning the design of potent drug-like compounds. Owing to the importance of this heterocyclic system, the present paper is an attempt to the pharmacological activities, structural modifications and the structure-activity relationship (SAR) reported for bridgehead nitrogen heterocycles in the current literature, making an effort to highlight the importance and therapeutic potentials of the pyrrolo[2,1-f][1,2,4]triazine scaffold and its bridgehead nitrogen bioisosters as heterocyclic privileged medicinal scaffolds.

  20. synthesis and characterization of some poly functionalized heterocyclic derivatives of expected biological activity

    International Nuclear Information System (INIS)

    El-sayed, M.S.

    2001-01-01

    The present work was aimed and designed to fulfil The following objectives : 1- Continuation of the effort done by our research group in the field of chemistry of pyridinethione derivatives and their biological activities. 2- Synthesis of several new heterocyclic derivatives containing N and/or S using the laboratory available reagents. 3- Establishment of the structures of the newly synthesized heterocyclic compounds by the data of IR, 1 H-NMR, mass spectra in addition to the elemental analysis. 4- Synthesis of some of these heterocyclic derivatives via alternative routs and this used as a tool to confirm the structures of the newly synthesized heterocyclic derivatives. 5- study of the most probable mechanisms leading to the formation of the new heterocyclic derivatives. 6- The antimicrobial activity of some of the newly synthesized heterocyclic derivatives was tested against several types of organisms

  1. Does the Effect of Micro-Environmental Factors on a Street’s Appeal for Adults’ Bicycle Transport Vary across Different Macro-Environments? An Experimental Study

    OpenAIRE

    Mertens, Lieze; Van Cauwenberg, Jelle; Ghekiere, Ariane; Van Holle, Veerle; De Bourdeaudhuij, Ilse; Deforche, Benedicte; Nasar, Jack; Van de Weghe, Nico; Van Dyck, Delfien

    2015-01-01

    Background : Characteristics of the physical environment can be classified into two broad categories: macro-("raw" urban planning features influenced on a regional level) and micro-(features specifically within a streetscape influenced on a neighborhood level) environmental factors. In urban planning applications, it is more feasible to modify conditions at the neighborhood level than at the regional level. Yet for the promotion of bicycle transport we need to know whether relationships betwe...

  2. Synthesis and antibacterial activity of some heterocyclic derivatives of sulfanilamide

    Directory of Open Access Journals (Sweden)

    B.B. Subudhi

    2012-12-01

    Full Text Available Considering the promising antimicrobial potential of carbonic anhydrase inhibitors and heterocyclic compounds some heterocyclic derivatives of sulfanilamide (2a-e were synthesized. The diazotisation of sulfanilamide followed by substitution with ethylacetoacetate and further condensation yielded compounds 2a-c. Schiff base of sulfanilamide with salicylaldehyde on reaction with thioglycollic acid and chloroacetyl chloride resulted in compound 2d-e. The susceptibility of Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa to the title compounds (300 μg/disc was investigated and compared to that of nitrofurantoin (300 μg/disc and ciprofloxacin (25 μg/disc. The title compounds showed good antimicrobial activity.DOI: http://dx.doi.org/10.4314/bcse.v26i3.15

  3. Biotransformation of heterocyclic dinitriles by Rhodococcus erythropolis and fungal nitrilases

    Czech Academy of Sciences Publication Activity Database

    Vejvoda, Vojtěch; Šveda, Ondřej; Kaplan, Ondřej; Přikrylová, Věra; Elišáková, Veronika; Himl, Michal; Kubáč, David; Pelantová, Helena; Kuzma, Marek; Křen, Vladimír; Martínková, Ludmila

    2007-01-01

    Roč. 29, č. 7 (2007), s. 1119-1124 ISSN 0141-5492 R&D Projects: GA AV ČR IAA500200708; GA MŠk LC06010; GA MŠk OC D25.001 Institutional research plan: CEZ:AV0Z50200510 Keywords : amidase * arpegillus nniger * heterocyclic Subject RIV: EE - Microbiology, Virology Impact factor: 1.222, year: 2007

  4. Oxidation of methyl heterocyclic compounds on vanadium oxide catalysts

    International Nuclear Information System (INIS)

    Shimanskaya, M.V.; Lejtis, L.A.; Iovel', I.G.; Gol'dberg, Yu.Sh.; Skolmejstere, R.A.; Golender, L.O.

    1985-01-01

    Data on vapor-phase oxidation of methyl derivatives of thiophene, Δ 2 - thiazo line, pyridine, pyrazine and pyramidine on oxide vanadium-molybdenum catalysts to corresponding heterylaldehydes are generalized. The dependence of catalytic properties of oxide vanadium-molybdenum systems in oxidation reactions of methylheterocyclic compounds on V:Mo ratio in the catalyst is revealed. It is shown that heterocyclic compounds are coordinated by a heteroatom on Lewis centres of V-Mo-O-catalyst primarily with partially reduced vanadium ions

  5. Photoactivation of heterocyclic change-transfer complexes-electrolytes

    International Nuclear Information System (INIS)

    Studzinskij, O.P.; Ponomareva, R.P.; Proskuryakova, T.V.

    1999-01-01

    Effect of light on the systems containing of five- or six-number nitrogen-containing heterocycles, molecular iodine and different-nature organic solvents, has been studied by the methods of absorption spectroscopy and electric conductivity measurement. It has been ascertained that in proton-donor solvents the complexes of 1:1 composition are formed with charge transfer, their electric conductivity increasing essentially with photoactivation [ru

  6. Ruthenium sulfoxides structure and reactivity with nitrogen heterocyclic bases

    International Nuclear Information System (INIS)

    Oliveira, Denise de.

    1990-01-01

    Ruthenium (II) sulfoxides are compounds of great interest in oxidative catalysis and in chemotherapy. In order to contribute for the understanding of the chemistry and electronic structure of this class of compounds, it has been studied a series of [Ru Cl 2 (S-DMSO) 2 L x ] complexes, where x = 1 (polymeric compounds) or 2 (monomers) and L N-heterocyclic ligands (pyridine, pyrazine and imidazole derivatives). The nature of N-heterocyclic ligand and their coordination are of great relevance to the stability, spectroscopic and electrochemical characteristics of the complexes. The trans-interactions are extremely important in this series, influencing the strength of the Ru(II)-> S-DMSO and Ru(II)-> L π-back donation. The DMSO and L ligands are π-acceptors. The metal-> ligand π-back donation is strengthened when the ligand is trans to chloride, which is π-donor, due to trans-cooperative interactions of the type: π-donor -> Ru(II) π-acceptor. Another interesting aspect in the series of [Ru Cl 2 (S-DMSO) 2 L 2 ] complexes is the occurrence of dissociative equilibria in the solution, due to the existence of three types of ligands. It was observed that the trans-N isomer of 2,6-dimethyl pyrazine derivative undergoes thermal substitution, with preferential liabilization of the N-heterocyclic ligand. Chloride ion is the most inert ligand in this complex. (author). 145 refs., 76 figs., 21 tabs

  7. Partitioning-separation of metal ions using heterocyclic ligands

    International Nuclear Information System (INIS)

    Hudson, M.J.; Drew, M.G.B.; Iveson, P.B.; Russell, M.L.

    2001-01-01

    Some guidelines are proposed for the effective design of heterocyclic ligands for partitioning because there is no doubt that the correct design of a molecular extractant is required for the effective separation of metal ions such as actinides(III) from lanthanides(III). Heterocyclic ligands with aromatic ring systems have a rich chemistry, which is only now becoming sufficiently well understood in relation to the partitioning process. The synthesis, characterisation and structures of some chosen molecules will be introduced in order to illustrate some important features. For example, the molecule N-carboxy-butyl-2-amino-4,6-di (2-pyridyl)-1,3,5-triazine (BADPTZ), which is an effective solvent extraction reagent for actinides and lanthanides, has been synthesised, characterised and its interaction with lanthanide ions studied. The interesting and important features of this molecule will be compared with those of other heterocyclic molecules such as 2,6-bis(5-butyl-1,2,4-triazole-3-yl) pyridine (DBTZP), which is a candidate molecule for the commercial separation of actinides and lanthanide elements. (author)

  8. Heterocycles by Transition Metals Catalyzed Intramolecular Cyclization of Acetylene Compounds

    International Nuclear Information System (INIS)

    Vizer, S.A.; Yerzhanov, K.B.; Dedeshko, E.C.

    2003-01-01

    Review shows the new strategies in the synthesis of heterocycles, having nitrogen, oxygen and sulfur atoms, via transition metals catalyzed intramolecular cyclization of acetylenic compounds on the data published at the last 30 years, Unsaturated heterocyclic compounds (pyrroles and pyrroline, furans, dihydro furans and benzofurans, indoles and iso-indoles, isoquinolines and isoquinolinones, aurones, iso coumarins and oxazolinone, lactams and lactones with various substitutes in heterocycles) are formed by transition metals, those salts [PdCl 2 , Pd(OAc) 2 , HgCl 2 , Hg(OAc) 2 , Hg(OCOCF 3 ) 2 , AuCl 3 ·2H 2 O, NaAuCl 4 ·2H 2 O, CuI, CuCl], oxides (HgO) and complexes [Pd(OAc) 2 (PPh 3 )2, Pd(PPh 3 ) 4 , PdCl 2 (MeCN) 2 , Pd(OAc ) 2 /TPPTS] catalyzed intramolecular cyclization of acetylenic amines, amides, ethers, alcohols, acids, ketones and βdiketones. More complex hetero polycyclic systems typical for natural alkaloids can to obtain similar. Proposed mechanisms of pyrroles, isoquinolines, iso indoles and indoles, benzofurans and iso coumarins, thiazolopyrimidinones formation are considered. (author)

  9. Nucleobases in Space: Laboratory Studies of Polycyclic Aromatic Nitrogen Heterocycles

    Science.gov (United States)

    Elsila, Jamie; Mattioda, Andy; Bernstein, Max; Sandford, Scott; Hudgins, Doug

    2005-01-01

    Polycyclic Aromatic Nitrogen Heterocycles (PANHs) are heterocyclic aromatics Le., PAHs with carbon atoms replaced by a nitrogen atom. These molecules have been detected in meteorite extracts, and in general these nitrogen heterocycles are of astrobiological interest since this class of molecules include nucleobases, basic components of our nucleic acids. These compounds are predicted to be present in the interstellar medium and in Titan tholin, but have received relatively little attention. We will present spectra and reactions of PANHs, frozen in solid H2O at 12 K, conditions germane to astronomical observations. In contrast to simple PAHs, that do not interact strongly with solid H2O, the nitrogen atoms in PANHs are potentially capable of hydrogen bonding with H20 changing their spectra, complicating their remote detection on the surfaces of icy bodies. Moreover, we have studied the photo-chemistry of these interesting compounds under astrophysical conditions and will use our lab studies to assess a potential interstellar heritage of these compounds in carbonaceous chondrites.

  10. The reactions of anthronylidene carbene with some heterocyclic compounds

    International Nuclear Information System (INIS)

    Divisia, Bernadette

    1970-01-01

    The action of the anthronylidene carbene, generated by photochemical decomposition of 9-diazo 10-anthron, on four heterocyclic compounds (furan, thiophene, 1-methyl-pyrrole and 2,5-dihydrofuran) has been examined. Two classical carbene reactions have been observed: the addition on double bond (furan, thiophene, 1-methylpyrrole) and hydrogen atom abstraction of the heterocyclic compound (2,5-dihydrofuran). In the case of furan and thiophene, the cyclo-propanic compound resulting from the addition is spontaneously transformed into an ethylenic derivative by valence isomerization. The furan derivative undergoes a cis-trans isomerization, while the thiophene one undergoes an extra carbene attack. In the case of 1-methylpyrrole, the corresponding cyclo-propanic compound undergoes a ring cleavage, followed by a hydrogen atom migration leading to the formation of a substituted anthron. Only an allylic hydrogen atom selective abstraction of heterocyclic compound takes place in the reaction of anthronylidene carbene with 2,5-dihydrofuran. The asymmetrical coupling of radicals so obtained yields the corresponding substituted anthron. (author) [fr

  11. The public health nutrition intervention management bi-cycle: a model for training and practice improvement.

    Science.gov (United States)

    Hughes, Roger; Margetts, Barrie

    2012-11-01

    The present paper describes a model for public health nutrition practice designed to facilitate practice improvement and provide a step-wise approach to assist with workforce development. The bi-cycle model for public health nutrition practice has been developed based on existing cyclical models for intervention management but modified to integrate discrete capacity-building practices. Education and practice settings. This model will have applications for educators and practitioners. Modifications to existing models have been informed by the authors' observations and experiences as practitioners and educators, and reflect a conceptual framework with applications in workforce development and practice improvement. From a workforce development and educational perspective, the model is designed to reflect adult learning principles, exposing students to experiential, problem-solving and practical learning experiences that reflect the realities of work as a public health nutritionist. In doing so, it assists the development of competency beyond knowing to knowing how, showing how and doing. This progression of learning from knowledge to performance is critical to effective competency development for effective practice. Public health nutrition practice is dynamic and varied, and models need to be adaptable and applicable to practice context to have utility. The paper serves to stimulate debate in the public health nutrition community, to encourage critical feedback about the validity, applicability and utility of this model in different practice contexts.

  12. Predicting Free Flow Speed and Crash Risk of Bicycle Traffic Flow Using Artificial Neural Network Models

    Directory of Open Access Journals (Sweden)

    Cheng Xu

    2015-01-01

    Full Text Available Free flow speed is a fundamental measure of traffic performance and has been found to affect the severity of crash risk. However, the previous studies lack analysis and modelling of impact factors on bicycles’ free flow speed. The main focus of this study is to develop multilayer back propagation artificial neural network (BPANN models for the prediction of free flow speed and crash risk on the separated bicycle path. Four different models with considering different combinations of input variables (e.g., path width, traffic condition, bicycle type, and cyclists’ characteristics were developed. 459 field data samples were collected from eleven bicycle paths in Hangzhou, China, and 70% of total samples were used for training, 15% for validation, and 15% for testing. The results show that considering the input variables of bicycle types and characteristics of cyclists will effectively improve the accuracy of the prediction models. Meanwhile, the parameters of bicycle types have more significant effect on predicting free flow speed of bicycle compared to those of cyclists’ characteristics. The findings could contribute for evaluation, planning, and management of bicycle safety.

  13. An improved multi-value cellular automata model for heterogeneous bicycle traffic flow

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Sheng [College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, 310058 China (China); Qu, Xiaobo [Griffith School of Engineering, Griffith University, Gold Coast, 4222 Australia (Australia); Xu, Cheng [Department of Transportation Management Engineering, Zhejiang Police College, Hangzhou, 310053 China (China); College of Transportation, Jilin University, Changchun, 130022 China (China); Ma, Dongfang, E-mail: mdf2004@zju.edu.cn [Ocean College, Zhejiang University, Hangzhou, 310058 China (China); Wang, Dianhai [College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, 310058 China (China)

    2015-10-16

    This letter develops an improved multi-value cellular automata model for heterogeneous bicycle traffic flow taking the higher maximum speed of electric bicycles into consideration. The update rules of both regular and electric bicycles are improved, with maximum speeds of two and three cells per second respectively. Numerical simulation results for deterministic and stochastic cases are obtained. The fundamental diagrams and multiple states effects under different model parameters are analyzed and discussed. Field observations were made to calibrate the slowdown probabilities. The results imply that the improved extended Burgers cellular automata (IEBCA) model is more consistent with the field observations than previous models and greatly enhances the realism of the bicycle traffic model. - Highlights: • We proposed an improved multi-value CA model with higher maximum speed. • Update rules are introduced for heterogeneous bicycle traffic with maximum speed 2 and 3 cells/s. • Simulation results of the proposed model are consistent with field bicycle data. • Slowdown probabilities of both regular and electric bicycles are calibrated.

  14. Sociodemographic Factors, Population Density, and Bicycling for Transportation in the United States.

    Science.gov (United States)

    Nehme, Eileen K; Pérez, Adriana; Ranjit, Nalini; Amick, Benjamin C; Kohl, Harold W

    2016-01-01

    Transportation bicycling is a behavior with demonstrated health benefits. Population-representative studies of transportation bicycling in United States are lacking. This study examined associations between sociodemographic factors, population density, and transportation bicycling and described transportation bicyclists by trip purposes, using a US-representative sample. This cross-sectional study used 2009 National Household Travel Survey datasets. Associations among study variables were assessed using weighted multivariable logistic regression. On a typical day in 2009, 1% of Americans older than 5 years of age reported a transportation bicycling trip. Transportation cycling was inversely associated with age and directly with being male, with being white, and with population density (≥ 10,000 vs transportation. Twenty-one percent of transportation bicyclists reported trips to work, whereas 67% reported trips to social or other activities. Transportation bicycling in the United States is associated with sociodemographic characteristics and population density. Bicycles are used for a variety of trip purposes, which has implications for transportation bicycling research based on commuter data and for developing interventions to promote this behavior.

  15. An improved multi-value cellular automata model for heterogeneous bicycle traffic flow

    International Nuclear Information System (INIS)

    Jin, Sheng; Qu, Xiaobo; Xu, Cheng; Ma, Dongfang; Wang, Dianhai

    2015-01-01

    This letter develops an improved multi-value cellular automata model for heterogeneous bicycle traffic flow taking the higher maximum speed of electric bicycles into consideration. The update rules of both regular and electric bicycles are improved, with maximum speeds of two and three cells per second respectively. Numerical simulation results for deterministic and stochastic cases are obtained. The fundamental diagrams and multiple states effects under different model parameters are analyzed and discussed. Field observations were made to calibrate the slowdown probabilities. The results imply that the improved extended Burgers cellular automata (IEBCA) model is more consistent with the field observations than previous models and greatly enhances the realism of the bicycle traffic model. - Highlights: • We proposed an improved multi-value CA model with higher maximum speed. • Update rules are introduced for heterogeneous bicycle traffic with maximum speed 2 and 3 cells/s. • Simulation results of the proposed model are consistent with field bicycle data. • Slowdown probabilities of both regular and electric bicycles are calibrated

  16. Modular mechatronic system for stationary bicycles interfaced with virtual environment for rehabilitation.

    Science.gov (United States)

    Ranky, Richard G; Sivak, Mark L; Lewis, Jeffrey A; Gade, Venkata K; Deutsch, Judith E; Mavroidis, Constantinos

    2014-06-05

    Cycling has been used in the rehabilitation of individuals with both chronic and post-surgical conditions. Among the challenges with implementing bicycling for rehabilitation is the recruitment of both extremities, in particular when one is weaker or less coordinated. Feedback embedded in virtual reality (VR) augmented cycling may serve to address the requirement for efficacious cycling; specifically recruitment of both extremities and exercising at a high intensity. In this paper a mechatronic rehabilitation bicycling system with an interactive virtual environment, called Virtual Reality Augmented Cycling Kit (VRACK), is presented. Novel hardware components embedded with sensors were implemented on a stationary exercise bicycle to monitor physiological and biomechanical parameters of participants while immersing them in an augmented reality simulation providing the user with visual, auditory and haptic feedback. This modular and adaptable system attaches to commercially-available stationary bicycle systems and interfaces with a personal computer for simulation and data acquisition processes. The complete bicycle system includes: a) handle bars based on hydraulic pressure sensors; b) pedals that monitor pedal kinematics with an inertial measurement unit (IMU) and forces on the pedals while providing vibratory feedback; c) off the shelf electronics to monitor heart rate and d) customized software for rehabilitation. Bench testing for the handle and pedal systems is presented for calibration of the sensors detecting force and angle. The modular mechatronic kit for exercise bicycles was tested in bench testing and human tests. Bench tests performed on the sensorized handle bars and the instrumented pedals validated the measurement accuracy of these components. Rider tests with the VRACK system focused on the pedal system and successfully monitored kinetic and kinematic parameters of the rider's lower extremities. The VRACK system, a virtual reality mechatronic bicycle

  17. A bicycle safety index for evaluating urban street facilities.

    Science.gov (United States)

    Asadi-Shekari, Zohreh; Moeinaddini, Mehdi; Zaly Shah, Muhammad

    2015-01-01

    The objectives of this research are to conceptualize the Bicycle Safety Index (BSI) that considers all parts of the street and to propose a universal guideline with microscale details. A point system method comparing existing safety facilities to a defined standard is proposed to estimate the BSI. Two streets in Singapore and Malaysia are chosen to examine this model. The majority of previous measurements to evaluate street conditions for cyclists usually cannot cover all parts of streets, including segments and intersections. Previous models also did not consider all safety indicators and cycling facilities at a microlevel in particular. This study introduces a new concept of a practical BSI to complete previous studies using its practical, easy-to-follow, point system-based outputs. This practical model can be used in different urban settings to estimate the level of safety for cycling and suggest some improvements based on the standards.

  18. Synthesis of bicyclic alkaloids from the iridoid antirrhinoside

    DEFF Research Database (Denmark)

    Frederiksen, Signe Maria

    The present thesis describes the isolation of the iridoid glucoside antirrhinoside from Antirrhinum majus, and the approaches made towards its transformation into analogues of biologically active compounds, with special interest in syntheses of bicyclic alkaloids.A synthetic piperidine monoterpene...... or by reduction using lithium aluminum hydride. The piperidines were subjected to hydrogenation to remove the N-benzyl group. The compounds were tested for hypoglycaemic activity by Novo Nordisk, but no activity was observed.Another approach towards a synthetic piperidine monoterpene was attempted. The strategy...... involved preparation of a diol, which through treatment of its ditosyl derivative with an amine would afford a piperidine monoterpene. Antirrhinoside was protected as its 5,6-O-monoacetonide via its 5,6:4',6'-O-diacetonide. The 5,6-O-isopropylidene-derivative was hydrogenated to give the 3,4-dihydro...

  19. Modeling electric bicycle's lane-changing and retrograde behaviors

    Science.gov (United States)

    Tang, Tie-Qiao; Luo, Xiao-Feng; Zhang, Jian; Chen, Liang

    2018-01-01

    Recently, electric bicycle (EB) has been one important traffic tool due to its own merits. However, EB's motion behaviors (especially at a signalized/non-signalized intersection) are more complex than those of vehicle since it always has lane-changing and retrograde behaviors. In this paper, we propose a model to explore EB's lane-changing and retrograde behaviors on a road with a signalized intersection. The numerical results indicate that the proposed model can qualitatively describe each EB's lane-changing and retrograde behaviors near a signalized intersection, and that lane-changing and retrograde behaviors have prominent impacts on the signalized intersection (i.e., prominent jams and congestions occur). The above results show that EB should be controlled as a vehicle, i.e., lane-changing and retrograde behaviors at a signalized intersection should strictly be prohibited to improve the operational efficiency and traffic safety at the signalized intersection.

  20. New pentose dimers with bicyclic moieties from pretreated biomass

    DEFF Research Database (Denmark)

    Rasmussen, H.; Sørensen, Henrik Rokkjær; Tanner, David Ackland

    2017-01-01

    In lignocellulosic biorefinery processes involving enzyme catalysed reactions it is a challenge that enzyme inhibiting compounds are generated and liberated during pretreatment of the biomass. In this study the contribution to cellulase inhibition from xylooligosaccharides and newly discovered...... oligophenolic compounds from pilot scale pretreated wheat straw was assessed at two different pretreatment severities. An increase in severity of the pretreatment led to more oligophenol compounds and in turn the total overall cellulase inhibition increased. When the xylooligosaccharides were enzymatically...... degraded prior to cellulose hydrolysis, a relief in cellulase inhibition was observed, but some inhibition remained, suggesting that other components also played a role in inhibition. We propose that these components include dipentoses with bicyclic moieties and feruloylated tripentoses, because LC...

  1. Continuous variable transmission and regenerative braking devices in bicycles utilizing magnetorheological fluids

    Science.gov (United States)

    Cheung, Wai Ming; Liao, Wei-Hsin

    2013-04-01

    The use of magnetorheological (MR) fluids in vehicles has been gaining popular recently due to its controllable nature, which gives automotive designers more dimensions of freedom in functional designs. However, not much attention has been paid to apply it to bicycles. This paper is aimed to study the feasibility of applying MR fluids in different dynamic parts of a bicycle such as the transmission and braking systems. MR continuous variable transmission (CVT) and power generator assisted in braking systems were designed and analyzed. Both prototypes were fabricated and tested to evaluate their performances. Experimental results showed that the proposed designs are promising to be used in bicycles.

  2. Synthesis and Reactions of Five-Membered Heterocycles Using Phase Transfer Catalyst (PTC Techniques

    Directory of Open Access Journals (Sweden)

    Ahmed M. El-Sayed

    2014-01-01

    Full Text Available Phase transfer catalysts (PTCs have been widely used for the synthesis of organic compounds particularly in both liquid-liquid and solid-liquid heterogeneous reaction mixtures. They are known to accelerate reaction rates by facilitating formation of interphase transfer of species and making reactions between reagents in two immiscible phases possible. Application of PTC instead of traditional technologies for industrial processes of organic synthesis provides substantial benefits for the environment. On the basis of numerous reports it is evident that phase-transfer catalysis is the most efficient way for generation and reactions of many active intermediates. In this review we report various uses of PTC in syntheses and reactions of five-membered heterocycles compounds and their multifused rings.

  3. Rapid trifluoromethylation and perfluoroalkylation of five-membered heterocycles by photoredox catalysis in continuous flow.

    Science.gov (United States)

    Straathof, Natan J W; Gemoets, Hannes P L; Wang, Xiao; Schouten, Jaap C; Hessel, Volker; Noël, Timothy

    2014-06-01

    Trifluoromethylated and perfluoroalkylated heterocycles are important building blocks for the synthesis of numerous pharmaceutical products, agrochemicals and are widely applied in material sciences. To date, trifluoromethylated and perfluoroalkylated hetero-aromatic systems can be prepared utilizing visible light photoredox catalysis methodologies in batch. While several limitations are associated with these batch protocols, the application of microflow technology could greatly enhance and intensify these reactions. A simple and straightforward photocatalytic trifluoromethylation and perfluoroalkylation method has been developed in continuous microflow, using commercially available photocatalysts and microflow components. A selection of five-membered hetero-aromatics were successfully trifluoromethylated (12 examples) and perfluoroalkylated (5 examples) within several minutes (8-20 min). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Acrolein contributes strongly to antimicrobial and heterocyclic amine transformation activities of reuterin.

    Science.gov (United States)

    Engels, Christina; Schwab, Clarissa; Zhang, Jianbo; Stevens, Marc J A; Bieri, Corinne; Ebert, Marc-Olivier; McNeill, Kristopher; Sturla, Shana J; Lacroix, Christophe

    2016-11-07

    Glycerol/diol dehydratases catalyze the conversion of glycerol to 3-hydroxypropionaldehyde (3-HPA), the basis of a multi-component system called reuterin. Reuterin has antimicrobial properties and undergoes chemical conjugation with dietary heterocyclic amines (HCAs). In aqueous solution reuterin is in dynamic equilibrium with the toxicant acrolein. It was the aim of this study to investigate the extent of acrolein formation at various physiological conditions and to determine its role in biological and chemical activities. The application of a combined novel analytical approach including IC-PAD, LC-MS and NMR together with specific acrolein scavengers suggested for the first time that acrolein, and not 3-HPA, is the active compound responsible for HCA conjugation and antimicrobial activity attributed to reuterin. As formation of the HCA conjugate was observed in vivo, our results imply that acrolein is formed in the human gut with implications on detoxification of HCAs. We propose to re-define the term reuterin to include acrolein.

  5. Bioinspired aerobic oxidation of secondary amines and nitrogen heterocycles with a bifunctional quinone catalyst.

    Science.gov (United States)

    Wendlandt, Alison E; Stahl, Shannon S

    2014-01-08

    Copper amine oxidases are a family of enzymes with quinone cofactors that oxidize primary amines to aldehydes. The native mechanism proceeds via an iminoquinone intermediate that promotes high selectivity for reactions with primary amines, thereby constraining the scope of potential biomimetic synthetic applications. Here we report a novel bioinspired quinone catalyst system consisting of 1,10-phenanthroline-5,6-dione/ZnI2 that bypasses these constraints via an abiological pathway involving a hemiaminal intermediate. Efficient aerobic dehydrogenation of non-native secondary amine substrates, including pharmaceutically relevant nitrogen heterocycles, is demonstrated. The ZnI2 cocatalyst activates the quinone toward amine oxidation and provides a source of iodide, which plays an important redox-mediator role to promote aerobic catalytic turnover. These findings provide a valuable foundation for broader development of aerobic oxidation reactions employing quinone-based catalysts.

  6. N-heterocyclic carbene metal complexes as bio-organometallic antimicrobial and anticancer drugs.

    Science.gov (United States)

    Patil, Siddappa A; Patil, Shivaputra A; Patil, Renukadevi; Keri, Rangappa S; Budagumpi, Srinivasa; Balakrishna, Geetha R; Tacke, Matthias

    2015-01-01

    Late transition metal complexes that bear N-heterocyclic carbene (NHC) ligands have seen a speedy growth in their use as both, metal-based drug candidates and potentially active homogeneous catalysts in a plethora of C-C and C-N bond forming reactions. This review article focuses on the recent developments and advances in preparation and characterization of NHC-metal complexes (metal: silver, gold, copper, palladium, nickel and ruthenium) and their biomedical applications. Their design, syntheses and characterization have been reviewed and correlated to their antimicrobial and anticancer efficacies. All these initial discoveries help validate the great potential of NHC-metal derivatives as a class of effective antimicrobial and anticancer agents.

  7. C-H functionalization directed by transformable nitrogen heterocycles: synthesis of ortho-oxygenated arylnaphthalenes from arylphthalazines.

    Science.gov (United States)

    Rastogi, Shiva K; Medellin, Derek C; Kornienko, Alexander

    2014-01-21

    Two protocols for oxygenation of aromatic C-H bonds ortho-positioned to the phthalazine ring were developed. The transannulation of the phthalazine ring to a naphthalene moiety by an Inverse Electron Demand Diels-Alder (IEDDA) reaction led to the synthesis of naphtho[2,1-c]chromenes, 1-(ortho-hydroxyaryl)naphthalenes and 6,7-dihydrobenzo[b]naphtho[1,2-d]oxepine. This new strategy based on the utilization of transformable nitrogen heterocycles in C-H functionalization chemistry can be potentially applicable to the synthesis of a broad range of biaryl compounds.

  8. EncM, a versatile enterocin biosynthetic enzyme involved in Favorskii oxidative rearrangement, aldol condensation, and heterocycle-forming reactions

    Science.gov (United States)

    Xiang, Longkuan; Kalaitzis, John A.; Moore, Bradley S.

    2004-01-01

    The bacteriostatic natural product enterocin from the marine microbe “Streptomyces maritimus” has an unprecedented carbon skeleton that is derived from an aromatic polyketide biosynthetic pathway. Its caged tricyclic, nonaromatic core is derived from a linear poly-β-ketide precursor that formally undergoes a Favorskii-like oxidative rearrangement. In vivo characterization of the gene encM through mutagenesis and heterologous biosynthesis demonstrated that its protein product not only is solely responsible for the oxidative C—C rearrangement, but also facilitates two aldol condensations plus two heterocycle forming reactions. In total, at least five chiral centers and four rings are generated by this multifaceted flavoprotein. Heterologous expression of the enterocin biosynthesis genes encABCDLMN in Streptomyces lividans resulted in the formation of the rearranged metabolite desmethyl-5-deoxyenterocin and the shunt products wailupemycins D-G. Addition of the methyltransferase gene encK, which was previously proposed through mutagenesis to additionally assist EncM in the Favorskii rearrangement, shifted the production to the O-methyl derivative 5-deoxyenterocin. The O-methyltransferase EncK seems to be specific for the pyrone ring of enterocin, because bicyclic polyketides bearing pyrone rings are not methylated in vivo. Expression of encM with different combinations of homologous actinorhodin biosynthesis genes did not result in the production of oxidatively rearranged enterocin-actinorhodin hybrid compounds as anticipated, suggesting that wild-type EncM may be specific for its endogenous type II polyketide synthase or for benzoyl-primed polyketide precursors. PMID:15505225

  9. The Depolymerization of Poly(Ethylene Terephthalate) (PET) Using N-Heterocyclic Carbenes from Ionic Liquids

    Science.gov (United States)

    Kamber, Nahrain E.; Tsujii, Yasuhito; Keets, Kate; Waymouth, Robert M.; Pratt, Russell C.; Nyce, Gregory W.; Hedrick, James L.

    2010-01-01

    The depolymerization of the plastic polyethylene terephthalate (PET or PETE) is described in this laboratory procedure. The transesterification reaction used to depolymerize PET employs a highly efficient N-heterocyclic carbene catalyst derived from a commercially available imidazolium ionic liquid. N-heterocyclic carbenes are potent nucleophilic…

  10. Synthesis and antiacetylcholinesterase activity of new D-glyceraldehyde heterocyclic derivatives

    International Nuclear Information System (INIS)

    Scorzo, Cecilia M.; Fascio, Mirta L.; D'Accorso, Norma B.; Cabrera, Margarita Gutierrez; Saavedra, Luis Astudillo

    2010-01-01

    We report herein the convenient procedures for the syntheses of different heterocyclic compounds from 2,3-O-isopropylidene-D-glyceraldehyde using intramolecular cyclization, 1,3-dipolar cycloaddition or bimolecular coupling reactions. The products were characterized by 1 H and 13 C NMR spectroscopy and elemental analysis. The new heterocycles and their derivatives were evaluated as inhibitors of acetylcholinesterase enzyme. (author)

  11. Gold-catalyzed heterocyclizations in alkynyl- and allenyl-β-lactams

    Directory of Open Access Journals (Sweden)

    Pedro Almendros

    2011-05-01

    Full Text Available New gold-catalyzed methods using the β-lactam scaffold have been recently developed for the synthesis of different sized heterocycles. This overview focuses on heterocyclization reactions of allenic and alkynic β-lactams which rely on the activation of the allene and alkyne component. The mechanism as well as the regio- and stereoselectivity of the cyclizations are also discussed.

  12. Self-association and infrared spectres of some heterocyclic compounds based on pyrrol in solid state

    International Nuclear Information System (INIS)

    Mulloev, N.; Nurulloev, M.; Narziev, B.N.

    1993-01-01

    Present article is devoted to self-association and infrared spectres of some heterocyclic compounds based on pyrrol in solid state. The study results of self-association specified by molecular hydrogen bonds of some heterocyclic compounds based on pyrrol on spectres of infrared absorption of stretching vibrations of N-H group were considered.

  13. Investigations on organogermanium compounds; III. N-tributylgermyl-substituted aliphatic and heterocyclic amines

    NARCIS (Netherlands)

    Rijkens, F.; Janssen, M.J.; Kerk, G.J.M. van der

    1965-01-01

    A series of new organogermanium compounds containing a germanium‐nitrogen bond, in many of which the nitrogen atom forms part of an heterocyclic ring, are prepared, in some cases by new methods: transamination reactions and reactions of germoxanes with heterocyclic amines. Striking differences in

  14. The GR-value deviation from the additivity rule for irradiated systems containing heterocyclic compounds

    International Nuclear Information System (INIS)

    Nanobashvili, H.M.; Shanidze, G.V.; Khidesheli, G.I.; Panchvidze, M.V.

    1988-01-01

    The investigation of the low temperature radiolysis of binary systems containing heterocyclic compounds has been carried out. In the systems under study the G R -value deviation from the additivity rule is observed due to the energy transfer processes from matrix molecules. It is shown that heterocyclic compounds are good radioprotectors. (author)

  15. Carbon-14 labelled nitrogen heterocycles; the syntheses of three phosphodiesterase inhibitors

    International Nuclear Information System (INIS)

    Lawrie, K.W.M.; Novelli, C.E.A.; Saunders, David

    1995-01-01

    The syntheses of three heterocyclic phosphodiesterase inhibitors are described from a common radiolabelled precursor, namely 2-propoxybenzo[cyano- 14 C] nitrile. Conversion of the nitrile to the corresponding methyl ketone or amidine allows elaboration of the heterocycles radiolabelled within the ring systems. (Author)

  16. Microwave-assisted synthesis of bio-active heterocycles in aqueous media

    KAUST Repository

    Polshettiwar, Vivek

    2010-01-01

    Synthesis of bio-active heterocycles and fine chemicals in aqueous media are one of the best solutions for the development of green and sustainable protocols. To illustrate the advantages of aqueous MW chemistry in heterocycle synthesis, in this chapter, various synthetic pathways developed in recent years in aqueous reaction media using microwave irradiation are described.

  17. Carbon-14 labelled nitrogen heterocycles; the syntheses of three phosphodiesterase inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Lawrie, K.W.M.; Novelli, C.E.A.; Saunders, David [SmithKline Beecham Pharmaceuticals Research and Development, Harlow (United Kingdom). Synthetic Isotope Chemistry Dept.; Coates, W.J. [SmithKline Beecham Pharmaceuticals Research and Development, Welwyn (United Kingdom)

    1995-09-01

    The syntheses of three heterocyclic phosphodiesterase inhibitors are described from a common radiolabelled precursor, namely 2-propoxybenzo[cyano-{sup 14}C] nitrile. Conversion of the nitrile to the corresponding methyl ketone or amidine allows elaboration of the heterocycles radiolabelled within the ring systems. (Author).

  18. Physiological responses and exercise preference between the Trikke and the bicycle ergometer

    Directory of Open Access Journals (Sweden)

    Eddie T.C. Lam

    2016-06-01

    Conclusion: Participants were more efficient in using the Trikke than the bicycle ergometer. The Trikke may be an enjoyable alternative for those individuals, particularly women, who have lost interest in traditional forms of exercise.

  19. Integration of bicycling and walking facilities into the infrastructure of urban communities.

    Science.gov (United States)

    2012-02-01

    Several manuals, handbooks and web resources exist to provide varied guidance on planning for and designing bicycle and pedestrian facilities, yet there are no specific indications about which of the varied treatments in these guides work well for us...

  20. Workshop to review problem-behavior research programs : pedestrian, bicycle, and pupil transportation safety

    Science.gov (United States)

    1981-09-01

    This report presents the proceedings of a workshop on pedestrian, bicycle, and pupil transportation safety. The purpose of this workshop was to develop specific recommendations for the planning and implementation of NHTSA research, development, and d...

  1. Associations Between Bicycling and Fall Related Physical Performance in Older Adults

    NARCIS (Netherlands)

    Pijnappels, M.A.G.M.

    2017-01-01

    Falls among older adults remains a significant public health issue. Bicycling positively influences falls risk factors including reduced balance, muscle weakness, and low self-perceived confidence in maintaining balance. However, this association has not been systematically examined. We recruited

  2. Evaluating Bicycle, Pedestrian, Transit and Economic Data Collection Needs and Measures of Effectiveness in Pennsylvania

    Science.gov (United States)

    2018-02-06

    The purpose of this research project was to evaluate the current data collection procedures for bicycle and pedestrian projects utilized by the Pennsylvania Department of Transportation (PennDOT) and Pennsylvania's Metropolitan Planning Organizations...

  3. 2002 bicycle transportation user survey ; developing intermodal connections for the 21st century

    Science.gov (United States)

    2004-12-01

    The Rhode Island Department of Transportation (RIDOT) has been on the forefront in recognizing the potential for bicycle travel to provide mobility, reduce congestion, improve environmental quality, and promote healthy lifestyles. An important compon...

  4. Aging road user, bicyclist, and pedestrian safety : effective bicycling signs and preventing left-turn crashes.

    Science.gov (United States)

    2013-09-01

    Task 1 of this report drivers' knowledge of various bicycle warning signs and pavement markings were assessed. In general knowledge was high. Share the Road and Three Foot Minimum signs were generally more quickly understood and recognized in version...

  5. An Analyses of Bicycle Accidents in Ankara: Analyses of 5 Years

    Directory of Open Access Journals (Sweden)

    Muhittin Yilmaz

    2014-12-01

    Full Text Available Aim: Bicycles are used for transportation, exercise and recreation. In this study we aimed to investigate the epidemiological, clinical and economic aspects of bicycle injuries. Material and Method: We included in the study who admitted to the Emergency Department with a bicycle accident between January 2008 and July 2012. Patient age and sex, accident pattern, presence of personal protective measures, injured body part, Glasgow Coma Scale (GCS score, Revised Trauma Score (RTS, radiological findings, requested consultations, duration of hospital stay, season of injury, and average cost rates were recorded. The study population was divided into 2 age groups as 0-14 years and over 14 years. Results: A patients were 238 (81.2% male and their mean age was 31.5±14.1 years. Fifty-five (18.8% patients were female and their mean age was 34.5±15.9 years. Males had significantly higher rate of bicycle injury (p

  6. Application of chalcones in heterocycles synthesis: Synthesis of 2 ...

    Indian Academy of Sciences (India)

    556. N Kaur and D Kishore gel G plates in the solvent system benzene–methanol ... in ice water (100mL) and stirred for 30min until the reaction mixture reached to ... acetate (0.033mol) in glacial acetic acid was refluxed for 5h. The reaction ...

  7. An insight into the biological activities of heterocyclic-fatty acid hybrid molecules.

    Science.gov (United States)

    Venepally, Vijayendar; Reddy Jala, Ram Chandra

    2017-12-01

    Heterocyclic compounds are the interesting core structures for the development of new bioactive compounds. Fatty acids are derived from renewable raw materials and exhibit various biological activities. Several researchers are amalgamating these two bioactive components to yield bioactive hybrid molecules with some desirable features. Heterocyclic-fatty acid hybrid derivatives are a new class of heterocyclic compounds with a broad range of biological activities and significance in the field of medicinal chemistry. Over the last few years, many research articles emphasized the significance of heterocyclic-fatty acid hybrid derivatives. The present review article focuses the developments in designing and biological evaluation of heterocyclic-fatty acid hybrid molecules. Copyright © 2017. Published by Elsevier Masson SAS.

  8. Teaching children about bicycle safety: an evaluation of the New Jersey Bike School program.

    Science.gov (United States)

    Lachapelle, Ugo; Noland, Robert B; Von Hagen, Leigh Ann

    2013-03-01

    There are multiple health and environmental benefits associated with increasing bicycling among children. However, the use of bicycles is also associated with severe injuries and fatalities. In order to reduce bicycle crashes, a bicycling education program was implemented in selected New Jersey schools and summer camps as part of the New Jersey Safe Routes to School Program. Using a convenience sample of participants to the program, an opportunistic study was designed to evaluate the effectiveness of two bicycle education programs, the first a more-structured program delivered in a school setting, with no on-road component, and the other a less structured program delivered in a summer camp setting that included an on-road component. Tests administered before and after training were designed to assess knowledge acquired during the training. Questions assessed children's existing knowledge of helmet use and other equipment, bicycle safety, as well as their ability to discriminate hazards and understand rules of the road. Participating children (n=699) also completed a travel survey that assessed their bicycling behavior and their perception of safety issues. Response to individual questions, overall pre- and post-training test scores, and changes in test scores were compared using comparison of proportion, t-tests, and ordinary least-squares (OLS) regression. Improvements between the pre-training and post-training test are apparent from the frequency distribution of test results and from t-tests. Both summer camps and school-based programs recorded similar improvements in test results. Children who bicycled with their parents scored higher on the pre-training test but did not improve as much on the post-training test. Without evaluating long-term changes in behavior, it is difficult to ascertain how successful the program is on eventual behavioral and safety outcomes. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Traumatic Globe Subluxation and Intracranial Injury Caused by Bicycle Brake Handle

    OpenAIRE

    Poroy; Cibik; Yazici

    2016-01-01

    Introduction Penetration of a bicycle brake handle into the orbit is a rare and serious type of trauma. Globe subluxation due to such trauma has not been previously reported. Case Presentation A 10-year-old girl presented after falling from a bicycle, which resulted in the handbrake penetrating her right upper eyelid. On examination, the globe was subluxated anteriorly, there was no light perception, and the pupilla was fixed and ...

  10. Stereocontrolled synthesis of polyhydroxylated bicyclic azetidines as a new class of iminosugars.

    Science.gov (United States)

    Malinowski, Maciej; Hensienne, Raphaël; Kern, Nicolas; Tardieu, Damien; Bodlenner, Anne; Hazelard, Damien; Compain, Philippe

    2018-06-12

    We report herein the development of a stereodivergent route towards polyhydroxylated bicyclic azetidine scaffolds, namely 6-azabicyclo[3.2.0]heptane derivatives. The strategy hinges on a common bicyclic β-lactam precursor, which is forged by way of a rare example of a cationic Dieckmann-type reaction, followed by IBX-mediated desaturation. Substrate-controlled diastereoselective oxidations then allow the divergent preparation of novel iminosugar mimics.

  11. A novel stereoselective synthesis of N-heterocycles by intramolecular hydrovinylation

    DEFF Research Database (Denmark)

    Bothe, Ulrich; Rudbeck, H. C.; Tanner, David Ackland

    2001-01-01

    A novel method for the synthesis of bicyclic amines has been developed. Cyclisation of 1,6-dienes by intramolecular hydrovinylation in the presence of catalytic amounts of allylpalladium chloride dimer afforded bicyclic amines in one step. Added phosphines, silver salts, as well as the nature of ...

  12. 2-(2′-Pyridyl)-4,6-diphenylphosphinine versus 2-(2′-Pyridyl)-4,6-diphenylpyridine: Synthesis, Characterization, and Reactivity of Cationic RhIII and IrIII Complexes Based on Aromatic Phosphorus Heterocycles

    NARCIS (Netherlands)

    de Krom, I.; Broeckx, L.E.E.; Lutz, M.; Müller, Christian

    2013-01-01

    The bidentate P,N hybrid ligand 1 allows access for the first time to novel cationic phosphinine-based RhIII and IrIII complexes, broadening significantly the scope of low-coordinate aromatic phosphorus heterocycles for potential applications. The coordination chemistry of 1 towards RhIII and IrIII

  13. A Modified Cellular Automaton Approach for Mixed Bicycle Traffic Flow Modeling

    Directory of Open Access Journals (Sweden)

    Xiaonian Shan

    2015-01-01

    Full Text Available Several previous studies have used the Cellular Automaton (CA for the modeling of bicycle traffic flow. However, previous CA models have several limitations, resulting in differences between the simulated and the observed traffic flow features. The primary objective of this study is to propose a modified CA model for simulating the characteristics of mixed bicycle traffic flow. Field data were collected on physically separated bicycle path in Shanghai, China, and were used to calibrate the CA model using the genetic algorithm. Traffic flow features between simulations of several CA models and field observations were compared. The results showed that our modified CA model produced more accurate simulation for the fundamental diagram and the passing events in mixed bicycle traffic flow. Based on our model, the bicycle traffic flow features, including the fundamental diagram, the number of passing events, and the number of lane changes, were analyzed. We also analyzed the traffic flow features with different traffic densities, traffic components on different travel lanes. Results of the study can provide important information for understanding and simulating the operations of mixed bicycle traffic flow.

  14. Association of Sociodemographic and Perceived Environmental Factors with Public Bicycle Use among Taiwanese Urban Adults

    Directory of Open Access Journals (Sweden)

    Yung Liao

    2016-03-01

    Full Text Available Background: This study examined the sociodemographic and perceived environmental factors associated with public bicycle use among Taiwanese urban adults. Methods: A random-digit-dialing telephone-based cross-sectional survey was administered to Taiwanese urban adults aged 20–64 years in 2015. Data on sociodemographic variables, perceived environmental factors (for attributes identified in the International Physical Activity Questionnaire-Environmental Module, and public bicycle use were obtained from 1002 adults in three cities. Adjusted logistic regression was used. Results: After adjustment for potential confounders, the results showed that adults aged 20–29 years (odds ratio (OR = 4.42 with a university degree or higher (OR = 2.03 were more likely to use public bicycles. In addition, adults living in Kaohsiung City were less likely to use public bicycles (OR = 0.24. Adults who saw people being active (OR = 1.76; 95% CI: 1.05–2.86 and had positive aesthetic experiences of their environment (OR = 1.69 were more likely to use public bicycles. Conclusions: Our findings suggest that seeing physically active people and positive aesthetic perceptions of the environment are key factors for developing transportation policies and intervention strategies for promoting public bicycle use among Taiwanese urban adults.

  15. Evaluation of the dispersion effect in through movement bicycles at signalized intersection via cellular automata simulation

    Science.gov (United States)

    Jiang, Hang; Ma, Yongjian; Jiang, Lin; Chen, Guozhou; Wang, Dongwei

    2018-05-01

    At signalized intersection areas, bicycle traffic presents a dispersion feature which may influence the movements of vehicles during peak period. The primary objective of this study is to simulate the dispersion effect in through-movement bicycle traffic at intersection areas and evaluate its influence on through-movement traffic. A cellular automata (CA) model is developed and validated to simulate the operations of through-movement bicycle traffic departing from two types of intersection approaches. Simulation results show that bicycles benefit from the dispersion effect when they depart from the approach with an exclusive right-turn vehicle lane. But when bicycles travel from the approach with a shared right-turn and through vehicle lane, the dispersion effect will result in friction interference and block interference on through-movement vehicles. Bicycle interferences reduce the vehicle speed and increase the delay of through-movement vehicles. The policy implications in regard to the dispersion effect from two types of approaches are discussed to improve the performance of through-movement traffic operations at signalized intersections.

  16. Synthesis and Characterization of Mono- and Bicycle Heterocyclic Derivatives Containing 1, 2,4-Triazole, 1,3,4-Thiadiazine and 1,3-Thiazole Rings

    Directory of Open Access Journals (Sweden)

    Navabeh Nami

    2012-01-01

    Full Text Available Reaction of tartaric acid with thiocarbohydrazide (2 and thiosemicarbazide (6 afforded 1,2-bis(4-amino-5-mercapto-4H-1,2,4-triazol-3-yl-ethane-1,2-diol (3 and 1,2-bis(5-mercapto-4H-1,2,4-triazol-3-yl-ethane-1,2-diol (7. Reaction of compounds 3 and 7 with DMAD (dimethylacety lendi carboxylate and DEAD (diethylacetylendicarboxylate gave 1,2-bis(7-[(z-methoxycarbonylmethylen]-5,6-dihydro-5H-6-one-[1,2,4] riazolo[3,4-b] [1,3,4] thiadiazin-3-yl-ethan-1,2-diol (4, 1,2-bis(7-[(z-ethoxycarbonylmethylen] -5,6-dihydro -5H-6-one-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-3-yl-ethan-1,2- diol (5 and 1,2-bis(6-[(z-methoxycarbonylmethylen]-5-oxo-[1,3]thiazolo[2,3-c] [1,2,4]triazol-3-yl-ethan-1,2-diol (8 in good yields.

  17. Synthesis of 2-arylidenebenzocycloalkanones containing N-donor heterocyclic rings

    Energy Technology Data Exchange (ETDEWEB)

    Sun, S.-W., E-mail: sunsw0819@163.com [Yuncheng University, Department of Applied Chemistry (China); Zhang, X., E-mail: zhangx@hit.edu.cn [Harbin Institute of Technology, Academy of Fundamental and Interdisciplinary Science (China); Wang, G.-F. [Yuncheng University, Department of Applied Chemistry (China)

    2016-12-15

    A series of 2-arylidenebenzocycloalkanones containing heterocyclic rings 1–8 were prepared and characterized by IR, {sup 1}H NMR and elemental analyses. X-ray diffraction study of 6 reveals that the cyclohexyl ring of the 3,4-dihydronaphthalen-1(2H)-one adopts a chair conformation with a maximum deviation of 0.547(3) Å and makes dihedral angles of 52.24(17)° and 11.23(16)°, respectively, with the benzene plane and the mean plane of the benzimidazole ring.

  18. Condensed heterocycles with a thiazole ring. 13. Azinothiazoloquinoxalinium salts

    International Nuclear Information System (INIS)

    Nesterenko, Yu.A.; Romanov, N.N.

    1987-01-01

    The condensation of 2,3-dichloroquinoxaline with 2-mercaptopyridines and 2-mercaptoquinolines gave the corresponding derivatives of new heterocyclic systems, viz., azino[1',2':3,2]thaizolo[4,5-b]quinoxalinium salts, which can be used for the synthesis of cyanine dyes. The electronic spectra of solutions of the compounds were obtained with an SF-8 spectrophotometer. The PMR spectra of solutions of CF 3 COOD were recorded with a BS-467 spectrometer (60 MHz) with hexamethyldisiloxane (HMDS) as the external standard

  19. Examining Capacity and Functioning of Bicycle Coalitions: A Descriptive Study

    Directory of Open Access Journals (Sweden)

    Melissa Bopp

    2017-11-01

    Full Text Available BackgroundBicycle coalitions represent a strong partner in creating bike-friendly communities through advocacy for physical infrastructure, encouragement for biking, or education about safety. Despite their versatility, little is known about their functioning. Therefore, the purpose of this study was to examine capacity, strengths, and weaknesses of these organizations.MethodsBicycle coalitions/advocacy groups from English-speaking countries were recruited to take part in an online survey via email invitation. The survey addressed basic information about the coalition (community demographics, location, leadership, communication strategies, coalition priorities, barriers to programming/activities, and partners.ResultsCoalitions (n = 56 from four countries completed the survey. Most coalitions operated as a non-profit (n = 44, 95.7%, 45% (n = 21 have paid staff as leaders, while 37% (n = 17 have volunteers as leaders. The following skills were represented in coalitions’ leadership: fundraising (n = 31, 53.4%, event planning (n = 31, 53.4%, urban planning (n = 26, 44%, and policy/legislation expertise (n = 26, 44.8%. Education (n = 26, 63.4% and encouragement (n = 25, 61.6% were viewed as top priorities and the safety of bicyclists (n = 21, 46.7% and advocacy for infrastructure and policy (n = 22, 48.9% is the focus of most activities. A lack of financial resources (n = 36, 81.8% and capable personnel (n = 25, 56.8% were significant barriers to offering programming in the community and that the availability of grants to address issues (n = 38, 86.4% would be the top motivator for improvements.ConclusionBike coalitions represent a critical partner in creating activity-friendly environments and understanding their capacity allows for creating skill/capacity building intervention programs, development of effective toolkits and fostering strong collaborations to address physical inactivity.

  20. Synthesis of heterocyclic chalcone derivatives and their radical scavenging ability toward 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals

    International Nuclear Information System (INIS)

    Hwang, Kijun; Kim, Hoseok; Kim, Beomtae; Han, Incheol

    2012-01-01

    A series of heterocyclic chalcone derivatives bearing heterocycles such as thiophene or furan ring as an isostere of benzene ring were carefully prepared, and the influence of heterocycles on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities was systematically investigated. Structure-activity relationships (SAR) analysis showed that the activities of thiophene ring-containing chalcones were higher than those of furan ring containing chalcones, and the presence of methyl substituent of heterocyclic ring distinctly affected the activities compared with non-substituted heterocycles in an opposite manner, with the 4'-methyl group of thiophene ring increasing activity and the 3'-methyl group of the furan ring decreasing activity. The distinct isosteric effect of heterocycles (i.e., thiophene or furan ring) on radical scavenging activities of heterocyclic chalcones was distinctly demonstrated in our work

  1. Bicycle Frame Prediction Techniques with Fuzzy Logic Method

    Directory of Open Access Journals (Sweden)

    Rafiuddin Syam

    2015-03-01

    Full Text Available In general, an appropriate size bike frame would get comfort to the rider while biking. This study aims to predict the simulation system on the bike frame sizes with fuzzy logic. Testing method used is the simulation test. In this study, fuzzy logic will be simulated using Matlab language to test their performance. Mamdani fuzzy logic using 3 variables and 1 output variable intake. Triangle function for the input and output. The controller is designed in the type mamdani with max-min composition and the method deffuzification using center of gravity method. The results showed that height, inseam and Crank Size generating appropriate frame size for the rider associated with comfort. Has a height range between 142 cm and 201 cm. Inseam has a range between 64 cm and 97 cm. Crank has a size range between 175 mm and 180 mm. The simulation results have a range of frame sizes between 13 inches and 22 inches. By using the fuzzy logic can be predicted the size frame of bicycle suitable for the biker.

  2. Bicycle Frame Prediction Techniques with Fuzzy Logic Method

    Directory of Open Access Journals (Sweden)

    Rafiuddin Syam

    2017-03-01

    Full Text Available In general, an appropriate size bike frame would get comfort to the rider while biking. This study aims to predict the simulation system on the bike frame sizes with fuzzy logic. Testing method used is the simulation test. In this study, fuzzy logic will be simulated using Matlab language to test their performance. Mamdani fuzzy logic using 3 variables and 1 output variable intake. Triangle function for the input and output. The controller is designed in the type mamdani with max-min composition and the method deffuzification using center of gravity method. The results showed that height, inseam and Crank Size generating appropriate frame size for the rider associated with comfort. Has a height range between 142 cm and 201 cm. Inseam has a range between 64 cm and 97 cm. Crank has a size range between 175 mm and 180 mm. The simulation results have a range of frame sizes between 13 inches and 22 inches. By using the fuzzy logic can be predicted the size frame of bicycle suitable for the biker.

  3. The Aeroflex: A Bicycle for Mobile Air Quality Measurements

    Science.gov (United States)

    Elen, Bart; Peters, Jan; Van Poppel, Martine; Bleux, Nico; Theunis, Jan; Reggente, Matteo; Standaert, Arnout

    2013-01-01

    Fixed air quality stations have limitations when used to assess people's real life exposure to air pollutants. Their spatial coverage is too limited to capture the spatial variability in, e.g., an urban or industrial environment. Complementary mobile air quality measurements can be used as an additional tool to fill this void. In this publication we present the Aeroflex, a bicycle for mobile air quality monitoring. The Aeroflex is equipped with compact air quality measurement devices to monitor ultrafine particle number counts, particulate mass and black carbon concentrations at a high resolution (up to 1 second). Each measurement is automatically linked to its geographical location and time of acquisition using GPS and Internet time. Furthermore, the Aeroflex is equipped with automated data transmission, data pre-processing and data visualization. The Aeroflex is designed with adaptability, reliability and user friendliness in mind. Over the past years, the Aeroflex has been successfully used for high resolution air quality mapping, exposure assessment and hot spot identification. PMID:23262484

  4. The Bicycle as a Tool of Ecological Emancipation

    Directory of Open Access Journals (Sweden)

    Klemen Ploštajner

    2015-12-01

    Full Text Available Sustainable development and ecological politics too often act as a mechanism for strengthening alienated state institutions or as a way for developing new market niches for the accumulation of capital. The article tries to offer a critique of technocratic visions of sustainable development by using the bike as a tool of emancipatory politics, and think about political ecology as means for building a community. The bicycle can be seen as an autonomous means of transportation stimulating the construction of ecological urban landscape, which is oriented towards users and community. It stimulates compressed and rationally used urban space, enforces heterogeneous urban plans, increases mixing of diverse practices and needs, liberates public space, which is now subordinated to parking spots and roads, and promotes rights and powers of the users, their autonomy and spontaneity, by enabling the development of open public streets, which are more than just a movement channel. The city, at present subordinated to ecological and social devastation of automobility, is—through extensive usage of bike—re-created as a space for the construction of social, autonomous and ecological community.

  5. How bicycle level of traffic stress correlate with reported cyclist accidents injury severities: A geospatial and mixed logit analysis.

    Science.gov (United States)

    Chen, Chen; Anderson, Jason C; Wang, Haizhong; Wang, Yinhai; Vogt, Rachel; Hernandez, Salvador

    2017-11-01

    Transportation agencies need efficient methods to determine how to reduce bicycle accidents while promoting cycling activities and prioritizing safety improvement investments. Many studies have used standalone methods, such as level of traffic stress (LTS) and bicycle level of service (BLOS), to better understand bicycle mode share and network connectivity for a region. However, in most cases, other studies rely on crash severity models to explain what variables contribute to the severity of bicycle related crashes. This research uniquely correlates bicycle LTS with reported bicycle crash locations for four cities in New Hampshire through geospatial mapping. LTS measurements and crash locations are compared visually using a GIS framework. Next, a bicycle injury severity model, that incorporates LTS measurements, is created through a mixed logit modeling framework. Results of the visual analysis show some geospatial correlation between higher LTS roads and "Injury" type bicycle crashes. It was determined, statistically, that LTS has an effect on the severity level of bicycle crashes and high LTS can have varying effects on severity outcome. However, it is recommended that further analyses be conducted to better understand the statistical significance and effect of LTS on injury severity. As such, this research will validate the use of LTS as a proxy for safety risk regardless of the recorded bicycle crash history. This research will help identify the clustering patterns of bicycle crashes on high-risk corridors and, therefore, assist with bicycle route planning and policy making. This paper also suggests low-cost countermeasures or treatments that can be implemented to address high-risk areas. Specifically, with the goal of providing safer routes for cyclists, such countermeasures or treatments have the potential to substantially reduce the number of fatalities and severe injuries. Published by Elsevier Ltd.

  6. On the Implications of Sense of Control over Bicycling : Design of a Physical Stamina-Aware Bike

    OpenAIRE

    Lee, Chao-Lung; Lee, Da; Cheng, Yun-Maw; Sandnes, Frode Eika; Chen, Li-Chieh; Chen, Wei-Chia

    2010-01-01

    Bicycling has become a mainstream activity among the environmental aware generation. Bicycling communities have gradually shown interests in quantitative data of the bicycling experiences such as road roughness, inclination, pollution, etc. Bikers utilize these data to infer the possible stamina cost and quality of surroundings. This supports them to make a better decision. This study assumes that fitness level indexed by stamina cost could enhance a biker's sense of c...

  7. Conductive Supramolecular Architecture Constructed from Polyoxovanadate Cluster and Heterocyclic Surfactant

    Directory of Open Access Journals (Sweden)

    Toshiyuki Misawa

    2018-01-01

    Full Text Available Proton-conductive solid electrolytes are significant for fuel-cell battery technology. Especially for use in motor vehicles, proton conductors which work at intermediate temperatures (373–673 K under an anhydrous atmosphere are desired to improve the fuel cell stability and efficiency. Inorganic–organic hybrid supramolecular architectures are a promising option for the realization of highly conductive proton conductors. Here, a hybrid layered crystal was synthesized for the first time by using an proton-containing decavanadate (V10 anion and a heterocyclic surfactant cation. A simple ion-exchange reaction led to the formation of an inorganic–organic hybrid of V10 by using dodecylpyridazinium (C12pda as the heterocyclic surfactant. Single crystal X-ray analyses revealed that four C12pda cations were associated with one V10 anion, which was a diprotonated species forming a one-dimensional infinite chain structure through hydrogen bonds. Anhydrous proton conductivity was investigated by alternating current (AC impedance spectroscopy in the range of 313–393 K, exhibiting a maximum value of 1.7 × 10−5 S cm−1 at 373 K.

  8. Sorption of Heterocyclic Organic Compounds to Multiwalled Carbon Nanotubes.

    Science.gov (United States)

    Metzelder, Florian; Funck, Matin; Schmidt, Torsten C

    2018-01-16

    Sorption is an important natural and technical process. Sorption coefficients are typically determined in batch experiments, but this may be challenging for weakly sorbing compounds. An alternative method enabling analysis of those compounds is column chromatography. A column packed with the sorbent is used and sorption data are determined by relating sorbate retention to that of a nonretarded tracer. In this study, column chromatography was applied for the first time to study sorption of previously hardly investigated heterocyclic organic compounds to multiwalled carbon nanotubes (MWCNTs). Sorption data for these compounds are very limited in literature, and weak sorption is expected from predictions. Deuterium oxide was used as nonretarded tracer. Sorption isotherms were well described by the Freundlich model and data showed reasonable agreement with predicted values. Sorption was exothermic and physisorption was observed. H-bonding may contribute to overall sorption, which is supported by reduced sorption with increasing ionic strength due to blocking of functional groups. Lowering pH reduced sorption of ionizable compounds, due to electrostatic repulsion at pH 3 where sorbent as well as sorbates were positively charged. Overall, column chromatography was successfully used to study sorption of heterocyclic compounds to MWCNTs and could be applied for other carbon-based sorbents.

  9. Thermally Stable Heterocyclic Imines as New Potential Nonlinear Optical Materials

    Science.gov (United States)

    Nesterov, Volodymyr V.; Antipin, Mikhail Y.; Nesterov, Vladimir N.; Moore, Craig E.; Cardelino, Beatriz H.; Timofeeva, Tatiana V.

    2004-01-01

    In the course of a search for new thermostable acentric nonlinear optical crystalline materials, several heterocyclic imine derivatives were designed, with the general structure D-pi-A(D'). Introduction of a donor amino group (D') into the acceptor moiety was expected to bring H-bonds into their crystal structures, and so to elevate their melting points and assist in an acentric molecular packing. Six heterocycle-containing compounds of this type were prepared, single crystals were grown for five of them, and these crystals were characterized by X-ray analysis. A significant melting temperature elevation was found for all of the synthesized compounds. Three of the compounds were also found to crystallize in acentric space groups. One of the acentric compounds is built as a three-dimensional H-bonded molecular network. In the other two compounds, with very similar molecular structure, the molecules form one-dimensional H-bonded head-to-head associates (chains). These chains are parallel in two different crystallographic directions and form very unusual interpenetrating chain patterns in an acentric crystal. Two of the compounds crystallized with centrosymmetric molecular packing.

  10. Heterocyclic aramid nanoparticle-assisted graphene exfoliation for fabrication of pristine graphene-based composite paper

    Energy Technology Data Exchange (ETDEWEB)

    Mo, Yao; Liu, Qi; Fan, Jinchen, E-mail: Jinchen.fan@shiep.edu.cn; Shi, Penghui; Min, Yulin, E-mail: ahaqmylin@126.com; Xu, Qunjie [Shanghai University of Electric Power, Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power, College of Environmental and Chemical Engineering (China)

    2015-07-15

    Mechanically strong, electrically conductive, and flexible pristine graphene-based composite paper was prepared based on heterocyclic aramid nanoparticle-assisted liquid-phase exfoliation of graphite. The macroscopic heterocyclic aramid yarns were split and assembled into heterocyclic aramid nanoparticles with the size of ∼30 nm by deprotonation in dimethylsulfoxide in the presence of potassium hydroxide. The obtained heterocyclic aramid nanoparticles dimethylsulfoxide dispersion was used as good medium solvent for highly efficiency liquid-phase exfoliation of graphite. The results demonstrated that the concentration of exfoliated graphene can facile reaches ∼2.72 mg/mL after direct sonication of 7 h with assist of heterocyclic aramid nanoparticles. After exfoliation, the self-assembled pristine graphene-based composite paper was fabricated by vacuum-assisted filtration. Due to the introduction of heterocyclic aramid nanoparticles, the self-assembled pristine graphene/heterocyclic aramid nanoparticles composite paper exhibited good mechanical property with tensile strength of ∼129.7 MPa, meantime, has a high electrical conductivity of ∼1.42 × 10{sup 4} S/m.

  11. Heterocyclic aramid nanoparticle-assisted graphene exfoliation for fabrication of pristine graphene-based composite paper

    International Nuclear Information System (INIS)

    Mo, Yao; Liu, Qi; Fan, Jinchen; Shi, Penghui; Min, Yulin; Xu, Qunjie

    2015-01-01

    Mechanically strong, electrically conductive, and flexible pristine graphene-based composite paper was prepared based on heterocyclic aramid nanoparticle-assisted liquid-phase exfoliation of graphite. The macroscopic heterocyclic aramid yarns were split and assembled into heterocyclic aramid nanoparticles with the size of ∼30 nm by deprotonation in dimethylsulfoxide in the presence of potassium hydroxide. The obtained heterocyclic aramid nanoparticles dimethylsulfoxide dispersion was used as good medium solvent for highly efficiency liquid-phase exfoliation of graphite. The results demonstrated that the concentration of exfoliated graphene can facile reaches ∼2.72 mg/mL after direct sonication of 7 h with assist of heterocyclic aramid nanoparticles. After exfoliation, the self-assembled pristine graphene-based composite paper was fabricated by vacuum-assisted filtration. Due to the introduction of heterocyclic aramid nanoparticles, the self-assembled pristine graphene/heterocyclic aramid nanoparticles composite paper exhibited good mechanical property with tensile strength of ∼129.7 MPa, meantime, has a high electrical conductivity of ∼1.42 × 10 4  S/m.

  12. Bicycle-friendly infrastructure planning in Beijing and Copenhagen - between adapting design solutions and learning local planning cultures

    DEFF Research Database (Denmark)

    Zhao, Chunli; Carstensen, Trine Agervig; Nielsen, Thomas Alexander Sick

    2018-01-01

    Abstract Cities around the world are constructing bicycle infrastructure to increase cycling. However, identifying efficient design solutions and determining how bicycle infrastructure planning knowledge can be integrated into comprehensive policy remains a challenge. The objective of this paper...... is to shed light on the strengths and weaknesses of current bicycle infrastructure planning in both an experienced city, Copenhagen, and in a less experienced city, Beijing. The paper examines how local design solutions are identified, how efficient they are and to what extent bicycle infrastructure planning...

  13. The use of bicycle workstations to increase physical activity in secondary classrooms

    Directory of Open Access Journals (Sweden)

    Alicia Fedewa

    2017-11-01

    Full Text Available Background To date, the majority of interventions have implemented classroom-based physical activity (PA at the elementary level; however, there is both the potential and need to explore student outcomes at high-school level as well, given that very few studies have incorporated classroom-based PA interventions for adolescents. One exception has been the use of bicycle workstations within secondary classrooms. Using bicycle workstations in lieu of traditional chairs in a high school setting shows promise for enhancing adolescents’ physical activity during the school day. Participants and procedure The present study explored the effects of integrating bicycle workstations into a secondary classroom setting for four months in a sample of 115 adolescents using an A-B-A-B withdrawal design. The study took place in one Advanced Placement English classroom across five groups of students. Physical activity outcomes included average heart rate, and caloric expenditure. Behavioural outcomes included percentage of on-task/off-task behaviour and number of teacher prompts in redirecting off-task behaviour. Feasibility and acceptability data of using the bicycle workstations were also collected. Results Findings showed significant improvements in physical activity as measured by heart rate and caloric expenditure, although heart rate percentage remained in the low intensity range when students were on the bicycle workstations. No effects were found on students’ on-task behaviour when using the bicycle workstations. Overall, students found the bikes acceptable to use but noted disadvantages of them as well. Conclusions Using bicycle workstations in high-school settings appears promising for enhancing low-intensity physical activity among adolescents. The limitations of the present study and implications for physical activity interventions in secondary schools are discussed.

  14. Antiradiation compounds XV: condensations of carbon disulfide with amino, chloro, cyanomethyl, and sulfonamido heterocycles

    International Nuclear Information System (INIS)

    Foye, W.O.; Kauffman, J.M.; Lanzillo, J.J.; LaSala, E.F.

    1975-01-01

    Condensations of carbon disulfide were carried out with amino, chloro, and diamino heterocycles to give condensed ring thiazoline-2-thiones and imidazoline-2-thiones, with cyanomethyl heterocycles to give dithio acid derivatives, and with heterocyclic sulfonamides to give sulfonyldithiocarbamates. Of several examples tested, pyrido[3,2-d]thiazoline-2-thione, disodium 2-(5-chloro-2-thienyl)-3,3-dimercaptoacrylonitrile, triethylammonium 4-sulfamoylphenyldithiocarbamate, ammonium β-phenethyldithiocarbamate, and methyl N-(thiophene-2-sulfonyl)dithiocarbamate, only the last-named compound showed any radiation protection for mice. Several compounds gave negative tests for antimalarial activity

  15. Modular mechatronic system for stationary bicycles interfaced with virtual environment for rehabilitation

    Science.gov (United States)

    2014-01-01

    Background Cycling has been used in the rehabilitation of individuals with both chronic and post-surgical conditions. Among the challenges with implementing bicycling for rehabilitation is the recruitment of both extremities, in particular when one is weaker or less coordinated. Feedback embedded in virtual reality (VR) augmented cycling may serve to address the requirement for efficacious cycling; specifically recruitment of both extremities and exercising at a high intensity. Methods In this paper a mechatronic rehabilitation bicycling system with an interactive virtual environment, called Virtual Reality Augmented Cycling Kit (VRACK), is presented. Novel hardware components embedded with sensors were implemented on a stationary exercise bicycle to monitor physiological and biomechanical parameters of participants while immersing them in an augmented reality simulation providing the user with visual, auditory and haptic feedback. This modular and adaptable system attaches to commercially-available stationary bicycle systems and interfaces with a personal computer for simulation and data acquisition processes. The complete bicycle system includes: a) handle bars based on hydraulic pressure sensors; b) pedals that monitor pedal kinematics with an inertial measurement unit (IMU) and forces on the pedals while providing vibratory feedback; c) off the shelf electronics to monitor heart rate and d) customized software for rehabilitation. Bench testing for the handle and pedal systems is presented for calibration of the sensors detecting force and angle. Results The modular mechatronic kit for exercise bicycles was tested in bench testing and human tests. Bench tests performed on the sensorized handle bars and the instrumented pedals validated the measurement accuracy of these components. Rider tests with the VRACK system focused on the pedal system and successfully monitored kinetic and kinematic parameters of the rider’s lower extremities. Conclusions The VRACK

  16. Johnson Space Center's Free Range Bicycle Program.- Fall 2015 Intern Report

    Science.gov (United States)

    Lee-Stockton, Willem

    2015-01-01

    NASA's Johnson Space Center is a big place, encompassing 1,620 acres and more than a hundred buildings. Furthermore, there are reportedly 15 thousand employees, all of which have somewhere to be. To facilitate the movement of all these people JSC has historically relied on human power. Pedaling their way towards deep space, bicycles have been the go to method. Currently there are about 200 Free Range Bicycles at JSC. Free Range Bicycles belong to nobody, except NASA, and are available for anybody to use. They are not to be locked or hidden (although frequently are) and the intention is that there will always be a bike to hop on to get where you're going (although it may not be the bike you rode in on). Although not without its own shortcomings, the Free Range Bicycle Program has continued to provide low cost, simple transportation for NASA's JSC. In addition to the approximately 200 Free Range Bicycles, various larger divisions (like engineering) will often buy a few dozen bikes for their team members to use or individuals will bring their own personal bike to either commute or use on site. When these bicycles fall into disrepair or are abandoned (from retirees etc) they become a problem at JSC. They are an eye sore, create a safety hazard and make it harder to find a working bike in a time of need. The Free Range Program hopes to address this first problem by "tagging out" abandoned or out of service bicycles. A bright orange "DO NOT OPERATE" tag is placed on the bike and given a serial number for tracking purposes. See picture to the right. If the bike has an active owner with intentions to repair the bike the bottom of the tag has instructions for how to claim the abandoned bicycle. After being tagged the owner of the bicycle has 30 days to claim the bicycle and either haul it off site or get it repaired (and labeled) in accordance with Johnson's Bicycle Policy. If the abandoned bicycle is not claimed within 30 days it becomes the property of the Government. The

  17. Assessing the Bicycle Network in St. Louis: A PlaceBased User-Centered Approach

    Directory of Open Access Journals (Sweden)

    Bram Boettge

    2017-02-01

    Full Text Available To transition towards sustainability and increase low-impact transportation, city planners are integrating bicycle infrastructure in urban landscapes. Yet, this infrastructure only promotes cycling according to how well it is sited within a specific city. How to best site bicycle facilities is essential for sustainability planning. We review approaches to assessing and siting new bicycle facilities. Following sustainability science, we argue that active cyclists should be consulted to incorporate users’ site-specific knowledge into bicycle infrastructure assessments. We then pilot an approach that surveys cyclists concerning level of stress along routes ridden in St. Louis, MO, USA. Among the active cyclists surveyed (n = 89, we found stress correlates with speed limit, roadway classification, and number of lanes. Although cyclists surveyed in St. Louis prefer roads with bike lanes over roads with sharrows or no infrastructure, the presence of bicycle infrastructure had no correlation with reported levels of stress. The piloted survey and spatial analytic tool are transferable to other localities. For planners, the maps generated by this participant data approach identify high-stress routes as targets of new infrastructure or information to direct cyclists to safer routes. For bicyclists, the maps generated identify low-stress routes for recreation and commuting.

  18. Accident rates amongst regular bicycle riders in Tasmania, Australia.

    Science.gov (United States)

    Palmer, Andrew J; Si, Lei; Gordon, Jared M; Saul, Tim; Curry, Beverley A; Otahal, Petr; Hitchens, Peta L

    2014-11-01

    To characterise the demographics, cycling habits and accident rates of adult cyclists in Tasmania. Volunteers ≥18 years of age who had cycled at least once/week over the previous month provided information on demographics; cycling experience; bicycles owned; hours/km/trips cycled per week; cycling purpose; protective equipment used; and major (required third-party medical treatment or resulted ≥1 day off work) or minor (interfered with individuals' regular daily activities and/or caused financial costs) accidents while cycling. Over 8-months, 136 cyclists (70.6% male) completed the telephone survey. Mean (standard deviation) age was 45.4 (12.1) years with 17.1 (11.4) years of cycling experience. In the week prior to interview, cyclists averaged 6.6 trips/week (totalling 105.7km or 5.0h). The most common reason for cycling was commuting/transport (34% of trips), followed by training/health/fitness (28%). The incidence of major and minor cycling accidents was 1.6 (95% CI 1.1-2.0) and 3.7 (2.3-5.0) per 100,000km, respectively. Male sex was associated with a significantly lower minor accident risk (incidence rate ratio=0.34, p=0.01). Mountain biking was associated with a significantly higher risk of minor accident compared with road or racing, touring, and city or commuting biking (phealth and wellbeing; cyclists also contributed substantially to the local economy. Accident rates are higher in this sample than previously reported in Tasmania and internationally. Mountain biking was associated with higher risks of both major and minor accidents compared to road/racing bike riding. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Understanding bicycling in cities using system dynamics modelling.

    Science.gov (United States)

    Macmillan, Alexandra; Woodcock, James

    2017-12-01

    Increasing urban bicycling has established net benefits for human and environmental health. Questions remain about which policies are needed and in what order, to achieve an increase in cycling while avoiding negative consequences. Novel ways of considering cycling policy are needed, bringing together expertise across policy, community and research to develop a shared understanding of the dynamically complex cycling system. In this paper we use a collaborative learning process to develop a dynamic causal model of urban cycling to develop consensus about the nature and order of policies needed in different cycling contexts to optimise outcomes. We used participatory system dynamics modelling to develop causal loop diagrams (CLDs) of cycling in three contrasting contexts: Auckland, London and Nijmegen. We combined qualitative interviews and workshops to develop the CLDs. We used the three CLDs to compare and contrast influences on cycling at different points on a "cycling trajectory" and drew out policy insights. The three CLDs consisted of feedback loops dynamically influencing cycling, with significant overlap between the three diagrams. Common reinforcing patterns emerged: growing numbers of people cycling lifts political will to improve the environment; cycling safety in numbers drives further growth; and more cycling can lead to normalisation across the population. By contrast, limits to growth varied as cycling increases. In Auckland and London, real and perceived danger was considered the main limit, with added barriers to normalisation in London. Cycling congestion and "market saturation" were important in the Netherlands. A generalisable, dynamic causal theory for urban cycling enables a more ordered set of policy recommendations for different cities on a cycling trajectory. Participation meant the collective knowledge of cycling stakeholders was represented and triangulated with research evidence. Extending this research to further cities, especially in low

  20. Flow chemistry and polymer-supported pseudoenantiomeric acylating agents enable parallel kinetic resolution of chiral saturated N-heterocycles

    Science.gov (United States)

    Kreituss, Imants; Bode, Jeffrey W.

    2017-05-01

    Kinetic resolution is a common method to obtain enantioenriched material from a racemic mixture. This process will deliver enantiopure unreacted material when the selectivity factor of the process, s, is greater than 1; however, the scalemic reaction product is often discarded. Parallel kinetic resolution, on the other hand, provides access to two enantioenriched products from a single racemic starting material, but suffers from a variety of practical challenges regarding experimental design that limit its applications. Here, we describe the development of a flow-based system that enables practical parallel kinetic resolution of saturated N-heterocycles. This process provides access to both enantiomers of the starting material in good yield and high enantiopurity; similar results with classical kinetic resolution would require selectivity factors in the range of s = 100. To achieve this, two immobilized quasienantiomeric acylating agents were designed for the asymmetric acylation of racemic saturated N-heterocycles. Using the flow-based system we could efficiently separate, recover and reuse the polymer-supported reagents. The amide products could be readily separated and hydrolysed to the corresponding amines without detectable epimerization.

  1. Heterocyclic N-oxides - A Promising Class of Agents Against Tuberculosis, Malaria and Neglected Tropical Diseases.

    Science.gov (United States)

    Dos Santos Fernandes, Guilherme Felipe; Pavan, Aline Renata; Dos Santos, Jean Leandro

    2018-04-17

    Heterocyclic N-oxides have emerged as promising agents against a number of diseases and disorders, especially infectious diseases. This review analyzes the emergence and development of this scaffold in the medicinal chemistry, focusing mainly on the discovery of new heterocyclic N-oxide compounds with potent activity against tuberculosis, malaria and neglected tropical diseases (i.e. leishmaniasis and Chagas disease). A number of heterocyclic N-oxide are described herein, nevertheless, the following chemical classes deserve to be highlighted due to the large number of reports in the literature about their promising pharmacological effects: furoxan, benzofuroxan, quinoxaline 1,4-di-N-oxide, indolone N-oxide and benzimidazole N-oxide. In order to describe those most promising compounds, we included in this review only those most biologically active heterocyclic N-oxide published since 2000. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  2. Sulfur-Kβ /sub emission studies on sulfur-bearing heterocycles

    International Nuclear Information System (INIS)

    Phillips, D.R.; Andermann, G.G.; Fujiwara, F.

    1986-01-01

    Sulfur-K/β /sub x-ray fluorescence spectroscopy (XFS) has been used to study the electronic structure and bonding in sulfur-bearing heterocycles. XFS not only has the capability of experimentally measuring valence electron energies in molecular species, but can also provide intensity data which can help define the nature of the molecular orbitals defined by the electrons. This report discusses the feasibility of using XFS as an analytical tool for the determination of total and specific sulfur heterocycle content in samples. A variety of compounds were studied. These include thiophene, thiophene derivatives, tetranydrothiophene, several more complex saturated and unsaturated sulfur heterocycles, and heterocycles containing both sulfur and nitrogen. The sulfur-K/β /sub spectra were obtained using a double crystal spectrometer which provided an instrumental resolution of about 0.7 eV

  3. Synthesis and properties of nitrogenous heterocycles containing a spiro-fused cyclopropane fragment

    International Nuclear Information System (INIS)

    Tomilov, Yury V; Nefedov, Oleg M; Kostyuchenko, Irina V

    2000-01-01

    The published data on the methods of synthesis and chemical transformations of nitrogenous heterocyclic compounds spiro-fused with a cyclopropane fragment are described systematically and generalised. The bibliography includes 146 references.

  4. Recyclisation of carbo- and heterocyclic compounds involving malononitrile and its derivatives

    International Nuclear Information System (INIS)

    Litvinov, Victor P

    1999-01-01

    Published data on recyclisation reactions of carbo- and heterocycles with participation of malononitrile and recyclisation of compounds containing a malononitrile fragment or fragments with malononitrile as a synthon are surveyed, described systematically and analysed. The bibliography includes 206 references.

  5. Physicochemical Mechanisms of Synergistic Biological Action of Combinations of Aromatic Heterocyclic Compounds

    OpenAIRE

    Evstigneev, Maxim P.

    2013-01-01

    The mechanisms of synergistic biological effects observed in the simultaneous use of aromatic heterocyclic compounds in combination are reviewed, and the specific biological role of heteroassociation of aromatic molecules is discussed.

  6. Microwave-Assisted Synthesis of Bio-Active Heterocycles and Fine Chemicals in Aqueous Media

    Science.gov (United States)

    Human health, especially in the aging population, mostly depends on various medicines, and researchers are combating against emerging diseases by new drug discovery. Heterocyclic compounds hold a special place among pharmaceutically active natural products as well as synthetic co...

  7. Theoretical NMR spectroscopy of N-heterocyclic carbenes and their metal complexes

    KAUST Repository

    Falivene, Laura; Cavallo, Luigi

    2016-01-01

    Recent theoretical analysis of the NMR properties of free N-heterocyclic carbenes (NHC) and Metal-NHC complexes has complemented experiments, allowing the establishment of structure/property relationships and the rationalization of otherwise

  8. Studies of effect of heterocyclic dyes in photogalvanic cells for solar ...

    Indian Academy of Sciences (India)

    Unknown

    Studies of effect of heterocyclic dyes in photogalvanic cells for solar ... observed and current–voltage characteristics of the cell studied, and a mechanism has been proposed for the generation ... dye work effectively in the strong alkaline range.

  9. Basic nitrogen-heterocyclic compounds in the Murchison meteorite

    International Nuclear Information System (INIS)

    Stoks, P.G.; Schwartz, A.W.

    1982-01-01

    A fragment of the Murchison (C2) carbonaceous meteorite was analyzed for basic, N-heterocyclic compounds, by dual detector capillary gas chromatography as well as capillary gas chromatography/mass spectrometry, using two columns of different polarity. In the formic acid extract 2,4,6-trimethylpyridine, quinoline, isoquinoline, 2-methylquinoline and 4-methylquinoline were positively identified. In addition, a suite of alkylpyridines and quinolines and/or isoquinolines was tentatively identified from their mass spectra. The (iso)quinolines were found to contain methyl substituents exclusively. The distribution of the pyridines observed reveals a similarity to that observed from catalytic reactions of ammonia and simple aldehydes under conditions similar to those applied in Fischer-Tropsch type reactions. (author)

  10. Alkyne hydroarylation with Au N-heterocyclic carbene catalysts

    Directory of Open Access Journals (Sweden)

    Cristina Tubaro

    2013-02-01

    Full Text Available Mono- and dinuclear gold complexes with N-heterocyclic carbene (NHC ligands have been employed as catalysts in the intermolecular hydroarylation of alkynes with simple unfunctionalised arenes. Both mono- and dinuclear gold(III complexes were able to catalyze the reaction; however, the best results were obtained with the mononuclear gold(I complex IPrAuCl. This complex, activated with one equivalent of silver tetrafluoroborate, exhibited under acidic conditions at room temperature much higher catalytic activity and selectivity compared to more commonly employed palladium(II catalysts. Moreover, the complex was active, albeit to a minor extent, even under neutral conditions, and exhibited lower activity but higher selectivity compared to the previously published complex AuCl(PPh3. Preliminary results on intramolecular hydroarylations using this catalytic system indicate, however, that alkyne hydration by traces of water may become a serious competing reaction.

  11. Synthesis of heterocycle-attached methylidenebenzenesulfonohydrazones as antifungal agents.

    Science.gov (United States)

    Gao, Zhinan; Lv, Min; Li, Qin; Xu, Hui

    2015-11-15

    A series of heterocycle-attached methylidenebenzenesulfonohydrazone derivatives were synthesized and evaluated for their antifungal activities against seven phytopathogenic fungi such as Fusarium graminearum, Alternaria solani, Valsa mali, Phytophthora capsici, Fusarium solani, Botrytis cinerea, and Glomerella cingulata. Compounds 7b, 8d, 9a, 9b and 9d exhibited a good and broad-spectrum of antifungal activities against at least five phytopathogenic fungi at the concentration of 100 μg/mL. It demonstrated that addition of one double bond between the phenylsulfonylhydrazone fragment and the furan ring of 6a,b,d could afford more active compounds 9a,b,d; however, introduction of the nitro group on the phenyl ring of 6a-9a gave less potent compounds 6e-9e. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Radical fragmentation of six-membered oxygen-containing heterocycles

    International Nuclear Information System (INIS)

    Petryaev, E.P.; Kosobutskij, V.S.; Shadyro, O.I.

    1982-01-01

    Using chromatography, the composition and radiation-chemical yields of final products of desctruction of six-member saturated oxygen-containing heterocycles (the effect of #betta#-radiation on aqueous solutions of tetrahydropyran, 1,3-dioxane, 2,2 dimethyl-1,3 dioxane, 1,4-dioxane, paraldehyde) have been determined. It is established that the identified products are formed at the expense of decomposition of primary radicals of the initial compounds and point to the realization of the following fragmentation ways: 1) #betta#-scattering, 2) #betta#-scattering with a subsequent 1,5 migration of an H atom, 3) simultaneous rupture of two vicinal, relative to the radical center, bonds. A formation mechanism of the substances desctruction products is suggested. Material balance of the product yields of 1,3-dioxane radical synchronous decomposition is presented

  13. Radical Addition to Iminium Ions and Cationic Heterocycles

    Directory of Open Access Journals (Sweden)

    Johannes Tauber

    2014-10-01

    Full Text Available Carbon-centered radicals represent highly useful reactive intermediates in organic synthesis. Their nucleophilic character is reflected by fast additions to electron deficient C=X double bonds as present in iminium ions or cationic heterocycles. This review covers diverse reactions of preformed or in situ-generated cationic substrates with various types of C-radicals, including alkyl, alkoxyalkyl, trifluoromethyl, aryl, acyl, carbamoyl, and alkoxycarbonyl species. Despite its high reactivity, the strong interaction of the radical’s SOMO with the LUMO of the cation frequently results in a high regioselectivity. Intra- and intermolecular processes such as the Minisci reaction, the Porta reaction, and the Knabe rearrangement will be discussed along with transition metal and photoredox catalysis or electrochemical methods to generate the odd-electron species.

  14. Exploring the Chemistry of Bicyclic Isoxazolidines for the Multicomponent Synthesis of Glycomimetic Building Blocks.

    Science.gov (United States)

    Hoogenboom, Jorin; Lutz, Martin; Zuilhof, Han; Wennekes, Tom

    2016-10-07

    Starting from a chiral furanone, the nitrone-olefin [3 + 2] cycloaddition can be used to obtain bicyclic isoxazolidines for which we report a set of reactions to selectively modify each functional position. These synthetically versatile bicyclic isoxazolidines allowed us to obtain complex glycomimetic building blocks, like iminosugars, via multicomponent chemistry. For example, a library of 20 pipecolic acid derivatives, a recurring motif in various prescription drugs, could be obtained via a one-pot Staudinger/aza-Wittig/Ugi three-component reaction of a bicyclic isoxazolidine-derived azido-hemiacetal. Notably, specific pipecolic acids in this library were obtained via hydrolysis of an unique tricyclic imidate side product of the Ugi reaction. The azido-hemiacetal was also converted into an aza-C-glycoside iminosugar via an unprecendented one-pot Staudinger/aza-Wittig/Mannich reaction.

  15. Influence of the cognitive workload on bicycle safety at four-legged intersections

    DEFF Research Database (Denmark)

    Kveladze, Irma; Agerholm, Niels

    2018-01-01

    is the influence of workload capacity on bicyclists spatial behaviour in a natural environment of four-legged intersections. Method: Due to the traffic safety of test participants, the study is divided in two phases. In the first phase, the actual physical environment of the four-legged intersection and bicyclists......-legged intersection. The eye tracking glasses will be used to make video and audio recording of visible field of where or how long bicyclists are allocating their visual attention while riding a bicycle and facing obstacles when crossing the four-legged intersection. On the second phase, a bicycle riding simulator...... riding task. This will allow to understand the allocation of bicyclists attention between primary and secondary tasks, to reveal the limit of the information processing capacity during biking. Results expected: Two experimental results will be incorporated to gain in-depth knowledge on bicycle accidents...

  16. Investigation of the role of bicyclic peroxy radicals in the oxidation mechanism of toluene.

    Science.gov (United States)

    Birdsall, Adam W; Andreoni, John F; Elrod, Matthew J

    2010-10-07

    The products of the primary OH-initiated oxidation of toluene were investigated using the turbulent flow chemical ionization mass spectrometry technique under different oxygen, NO, and initial OH radical concentrations as well as a range of total pressures. The bicyclic peroxy radical intermediate, a key proposed intermediate species in the Master Chemical Mechanism (MCM) for the atmospheric oxidation of toluene, was detected for the first time. The toluene oxidation mechanism was shown to have a strong oxygen concentration dependence, presumably due to the central role of the bicyclic peroxy radical in determining the stable product distribution at atmospheric oxygen concentrations. The results also suggest a potential role for bicyclic peroxy radical + HO(2) reactions at high HO(2)/NO ratios. These reactions are postulated to be a source of the inconsistencies between environmental chamber results and predictions from the MCM.

  17. Conversion Of An Ordinary N Bicycle Into An Electric Bike And Related Research

    Directory of Open Access Journals (Sweden)

    Marius Janavičius

    2014-05-01

    Full Text Available An electric bicycle as a transport and leisure vehicle is expected to have a promising future. Currently, he market offers a great choice of factory electric bicycles and conversion kits to remake an ordinary bicycle into an electric bike. Also, the increasing number of electric vehicles is determined by the reduction in costs for manufacturing of batteries and an evolution in battery technology. This article presents the implementation of an electric bike by selecting the “Golden Motor Technology” company’s electric front wheel conversion kit MagicPie3 and 16 cell 10Ah LiFePO4 battery. After installation of the engine and other components, experiments were conducted to evaluate the performance characteristics of the electric bike and check the manufacturer’s specifications.

  18. A Remote Power Management Strategy for the Solar Energy Powered Bicycle

    Directory of Open Access Journals (Sweden)

    Chung-Hsing Chao

    2011-12-01

    Full Text Available In this paper, a solar energy powered bicycle by a wireless sensor network (WSN far-end network monitoring solar energy to transfer the electrical energy storage and the effectiveness analysis is proposed. In order to achieve this goal, an embarked ZigBee by a solar-powered bicycle the far-end wireless network supervisory system is setup. Experimental results prove that our prototype, the solar energy powered bicycle, can manage the solar energy for charging two Lead-Acid batteries pack. As a result, the user by the wireless network in parking period knows the data on the amount of immediate solar radiation, the degree of illumination, the ambient temperature, and electrical energy storage capacity information by the internet interface.

  19. Study of the health effects of bicycling in an urban atmosphere. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Waldman, M.; Weiss, S.; Articola, W.

    1977-10-14

    This report analyzes data on the health effects of bicycling in an urban environment through intensive study of ten healthy male subjects bicycling or driving in systematically varied conditions in the streets of Washington, D.C. Evaluation criteria for available technology and instrumentation are included and a methodology is developed for route selection. Specific air pollutants (carbon monoxide, ozone, sulfates, nitrates, and particulates) are measured concurrently with exposure and subsequent changes in health status identified through pulmonary function testing, cardiovascular testing, and blood and symptoms analysis. The report concludes that no major adverse short-term health effects were noted for ten healthy male subjects while bicycling or driving in levels of pollution and thermal stress encountered during the study period. Recommendations for further research are also presented.

  20. Traumatic Globe Subluxation and Intracranial Injury Caused by Bicycle Brake Handle.

    Science.gov (United States)

    Poroy, Ceren; Cibik, Cansu; Yazici, Bulent

    2016-09-01

    Penetration of a bicycle brake handle into the orbit is a rare and serious type of trauma. Globe subluxation due to such trauma has not been previously reported. A 10-year-old girl presented after falling from a bicycle, which resulted in the handbrake penetrating her right upper eyelid. On examination, the globe was subluxated anteriorly, there was no light perception, and the pupilla was fixed and dilated. Radiologic studies revealed orbitonasal fractures, hemorrhage, emphysema in the orbit and cranium, and rupture of the extraocular muscles. The globe was replaced into the orbit with the help of lateral cantholysis and orbital septotomy. During 22 months of follow-up, the globe remained intact, but total loss of vision, blepharoptosis, and extraocular motility restriction persisted. This case and previous reports show that bicycle brake handles can cause severe, penetrating orbital and cerebral traumas that can result in vision loss or fatality. Brake handles should be designed to protect bicyclists from such injuries.

  1. [Abortion using a bicycle pump on the mistress and unusual suicide of a blind man].

    Science.gov (United States)

    Holzer, F J

    1973-01-01

    In Tyrol a case of fatal air embolism after an abortion attempt with a bicycle pump, performed by a blind man who later committed suicide, is described. The bicycle tube was inserted into the vagina and air and a soapy solution were pumped in. Autopsies revealed internal bleeding, gas embolisms in the veins of the ovaries and heart, a bloody foamy liquid in the lungs, and an intact 14 cm male fetus. 3 similar cases of fatal air embolisms after abortion attempts with bicycle pumps are described. In 1 case a soapy solution had been injected. Abortion attempts with a pipe and a rubber catheter, reported here, also resulted in rapidly fatal air embolisms. In 1 case death occurred a few seconds after a partner blew air with his mouth into his pregnant mistress' vagina. It is concluded that under some conditions filling the vagina with air (tightly) can cause fatal air embolisms.

  2. Automatic Stabilization of a Riderless Bicycle using the Active Disturbance Rejection Control Approach

    Directory of Open Access Journals (Sweden)

    Mauro Baquero-Suárez

    2017-12-01

    Full Text Available This work proposes an ADRC (Active Disturbance Rejection Control strategy by disturbance extended observers to stabilize a moving riderless bicycle with a variant forward speed. Although the bicycle has an unstable and non-linear dynamics when in its upright position, which can be modeled as a LPV (Linear-Parameter-Varying system that depends on the forward speed, a simplified time-invariant and lumped-parameter model, with an nominal constant forward speed is used in the controller design. ADRC scheme groups discrepancies between the simplified model and the plant, with external disturbances into an equivalent additive unified disturbance signal at input, which is estimated via the observer and rejected through a linear control law. The effectiveness of this strategy is validated by a co-simulation between ADAMS and MATLAB, which exhibits a high performance and robustness in a virtual dynamic model of the bicycle, submitted to severe external disturbances and parameter variations.

  3. Perceiving and Acting on Complex Affordances: How Children and Adults Bicycle across Two Lanes of Opposing Traffic

    Science.gov (United States)

    Grechkin, Timofey Y.; Chihak, Benjamin J.; Cremer, James F.; Kearney, Joseph K.; Plumert, Jodie M.

    2013-01-01

    This investigation examined how children and adults negotiate a challenging perceptual-motor problem with significant real-world implications--bicycling across two lanes of opposing traffic. Twelve- and 14-year-olds and adults rode a bicycling simulator through an immersive virtual environment. Participants crossed intersections with continuous…

  4. The Politics of Bicycle Innovation: Comparing the American and Dutch Human-Powered Vehicle Movements, 1970s—present

    NARCIS (Netherlands)

    Stoffers, M.; Oldenziel, R; Trischler, H

    2016-01-01

    This paper deals with the history of the international Human-Powered Vehicle (HPV) movement, originally launched in the 1970s by engineers and scientists who believed that bicycle innovation could give a major impetus to a coveted western bicycle renaissance. Based on a reading of magazines and

  5. An experiment on rider stability while mounting : comparing middle-aged and elderly cyclists on pedelecs and conventional bicycles.

    NARCIS (Netherlands)

    Twisk, D.A.M. Platteel, S. & Lovegrove, G.R.

    2017-01-01

    Pedelecs, popular among elderly cyclists, are associated with a higher injury risk than conventional bicycles. About 17% of these injuries are due to falls while (dis)mounting. Using instrumented bicycles, this study aimed to identify factors contributing to the stability of self-chosen mounting

  6. The effects of operating a touch screen smartphone and other common activities performed while bicycling on cycling behaviour

    NARCIS (Netherlands)

    de Waard, Dick; Lewis Evans, Ben; Jelijs, Bart; Tucha, Oliver; Brookhuis, Karel

    Although it has been shown that making phone calls or sending text messages while riding a bicycle can have a negative impact on bicyclist’s behaviour, in countries such as the Netherlands the operation of a mobile phone while cycling on a bicycle is not illegal and is actually quite common. In

  7. Selective Access to Heterocyclic Sulfonamides and Sulfonyl Fluorides via a Parallel Medicinal Chemistry Enabled Method.

    Science.gov (United States)

    Tucker, Joseph W; Chenard, Lois; Young, Joseph M

    2015-11-09

    A sulfur-functionalized aminoacrolein derivative is used for the efficient and selective synthesis of heterocyclic sulfonyl chlorides, sulfonyl fluorides, and sulfonamides. The development of a 3-step parallel medicinal chemistry (PMC) protocol for the synthesis of pyrazole-4-sulfonamides effectively demonstrates the utility of this reagent. This reactivity was expanded to provide rapid access to other heterocyclic sulfonyl fluorides, including pyrimidines and pyridines, whose corresponding sulfonyl chlorides lack suitable chemical stability.

  8. Phosphorylated Derivatives of Alkaloids and Nitrogen-containing Heterocycles — Cholinesterase Inhibitors

    Science.gov (United States)

    Sadykov, Abid S.; Dalimov, D. N.; Godovikov, Nikolai N.

    1983-10-01

    The review deals with the synthesis and anticholinesterase activities of phosphorylated derivatives of certain alkaloids and nitrogen-containing heterocycles. It is shown that the conformational properties of the alkaloid and nitrogen-containing heterocycle residues in the composition of the organophosphorus inhibitor (OPI) molecule play an important role in the inhibition of the catalytic activity of cholinesterases. The type of inhibition of cholinesterases also varies as a function of chemical structure. The bibliography includes 45 references.

  9. Synthesis and antiacetylcholinesterase activity of new D-glyceraldehyde heterocyclic derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Scorzo, Cecilia M.; Fascio, Mirta L.; D' Accorso, Norma B. [Universidad de Buenos Aires, Buenos Aires (Argentina). Facultad de Ciencias Exactas y Naturales. Dept. de Quimica Organica; Cabrera, Margarita Gutierrez; Saavedra, Luis Astudillo [Universidad de Talca (Chile). Inst. de Quimica de Productos Naturales. Lab. de Sintesis Organica

    2010-07-01

    We report herein the convenient procedures for the syntheses of different heterocyclic compounds from 2,3-O-isopropylidene-D-glyceraldehyde using intramolecular cyclization, 1,3-dipolar cycloaddition or bimolecular coupling reactions. The products were characterized by {sup 1}H and {sup 13}C NMR spectroscopy and elemental analysis. The new heterocycles and their derivatives were evaluated as inhibitors of acetylcholinesterase enzyme. (author)

  10. An overview of the key routes to the best selling 5-membered ring heterocyclic pharmaceuticals

    Directory of Open Access Journals (Sweden)

    Nikzad Nikbin

    2011-04-01

    Full Text Available This review presents a comprehensive overview on selected synthetic routes towards commercial drug compounds as published in both journal and patent literature. Owing to the vast number of potential structures, we have concentrated only on those drugs containing five-membered heterocycles and focused principally on the assembly of the heterocyclic core. In order to target the most representative chemical entities the examples discussed have been selected from the top 200 best selling drugs of recent years.

  11. BICYCLE HELMET DESIGN AND THE VIRTUAL VALIDATION OF THE IMPACT, AERODYNAMICS AND PRODUCTION PROCESS

    Directory of Open Access Journals (Sweden)

    Bojan Boshevski

    2017-12-01

    Full Text Available This paper presents the development process of a bicycle helmet through individual research, creation, presentation and analysis of the results of the most important product development stages. The quality of the development and manufacturing process of the protective equipment for extreme sports is an imperative for a successful product and its flawless function. The design of the bicycle helmet is made following the rules of the design in order to create a well-founded and functional product. After creating design sketches, a virtual prototype was developed in "SolidWorks" using the required ergonomic dimensions. 3D printed model of the human head with adapted ergonomic dimensions and the designed bicycle helmet was developed in order to verify the applied ergonomic measures. The virtual model will be used as an input in the finite element analysis of the helmet impact test based on the EN1078 standard and the aerodynamic simulations executed in "SolidWorks Simulation and Flow Simulation", for verification of the impact and aerodynamic properties. Virtual testing of aerodynamic features and the ability of the bicycle helmet to allow ventilation of the user's head indicate that the helmet performs its function in the desired way. Also, the virtual prototype will be used for the production process simulation in "SolidWorks Plastics" in order to analyze the production of the bicycle helmet. The polycarbonate helmet outer shell is subject to a number of simulations for the sake of analyzing the production process in order to obtain the desired characteristics of the polycarbonate outer shell and to avoid the disadvantages that occur in the manufacturing process. The main goal of this paper is to develop a safety bicycle helmet with improved ergonomic, validation of impact, aerodynamic characteristics and production process in order to produce a high quality product for mass use.

  12. Development of a solar-powered electric bicycle in bike sharing transportation system

    Science.gov (United States)

    Adhisuwignjo, S.; Siradjuddin, I.; Rifa'i, M.; Putri, R. I.

    2017-06-01

    The increasing mobility has directly led to deteriorating traffic conditions, extra fuel consumption, increasing automobile exhaust emissions, air pollution and lowering quality of life. Apart from being clean, cheap and equitable mode of transport for short-distance journeys, cycling can potentially offer solutions to the problem of urban mobility. Many cities have tried promoting cycling particularly through the implementation of bike-sharing. Apparently the fourth generation bikesharing system has been promoted utilizing electric bicycles which considered as a clean technology implementation. Utilization of solar power is probably the development keys in the fourth generation bikesharing system and will become the standard in bikesharing system in the future. Electric bikes use batteries as a source of energy, thus they require a battery charger system which powered from the solar cells energy. This research aims to design and implement electric bicycle battery charging system with solar energy sources using fuzzy logic algorithm. It is necessary to develop an electric bicycle battery charging system with solar energy sources using fuzzy logic algorithm. The study was conducted by means of experimental method which includes the design, manufacture and testing controller systems. The designed fuzzy algorithm have been planted in EEPROM microcontroller ATmega8535. The charging current was set at 1.2 Amperes and the full charged battery voltage was observed to be 40 Volts. The results showed a fuzzy logic controller was able to maintain the charging current of 1.2 Ampere with an error rate of less than 5% around the set point. The process of charging electric bike lead acid batteries from empty to fully charged was 5 hours. In conclusion, the development of solar-powered electric bicycle controlled using fuzzy logic controller can keep the battery charging current in solar-powered electric bicycle to remain stable. This shows that the fuzzy algorithm can be used as

  13. Microwave Assisted Organic Synthesis of Heterocycles in Aqueous Media: Recent Advances in Medicinal Chemistry.

    Science.gov (United States)

    Frecentese, Francesco; Saccone, Irene; Caliendo, Giuseppe; Corvino, Angela; Fiorino, Ferdinando; Magli, Elisa; Perissutti, Elisa; Severino, Beatrice; Santagada, Vincenzo

    2016-01-01

    Green chemistry is a discipline of great interest in medicinal chemistry. It involves all fields of chemistry and it is based on the principle to conduct chemical reactions protecting the environment at the same time, through the use of chemical procedures able to avoid pollution. In this context, water as solvent is a good choice because it is abundant, nontoxic, non-caustic, and non-combustible. Even if microwave assisted organic reactions in conventional solvents have quickly progressed, in the recent years medicinal chemists have focused their attention to processes deemed not dangerous for the environment, using nanotechnology and greener solvents as water. Several reports of reaction optimizations and selectivities, demonstrating the capability of microwave to allow the obtaining of increased yields have been recently published using water as solvent. In this review, we selected the available knowledge related to microwave assisted organic synthesis in aqueous medium, furnishing examples of the newest strategies to obtain useful scaffolds and novel derivatives for medicinal chemistry purposes. The intention of this review is to demonstrate the exclusive ability of MAOS in water as solvent or as co-solvent. For this purpose we report here the most representative applications of MAOS using water as solvent, focusing on medicinal chemistry processes leading to interesting nitrogen containing heterocycles with potential pharmaceutical applications.

  14. [Distribution and sources of oxygen and sulfur heterocyclic aromatic compounds in surface soil of Beijing, China].

    Science.gov (United States)

    He, Guang-Xiu; Zhang, Zhi-Huan; Peng, Xu-Yang; Zhu, Lei; Lu, Ling

    2011-11-01

    62 surface soil samples were collected from different environmental function zones in Beijing. Sulfur and oxygen heterocyclic aromatic compounds were detected by GC/MS. The objectives of this study were to identify the composition and distribution of these compounds, and discuss their sources. The results showed that the oxygen and sulfur heterocyclic aromatic compounds in the surface soils mainly contained dibenzofuran, methyl- and C2-dibenzofuran series, dibenzothiophene, methyl-, C2- and C3-dibenzothiophene series and benzonaphthothiophene series. The composition and distribution of the oxygen and sulfur heterocyclic aromatic compounds in the surface soil samples varied in the different environmental function zones, of which some factories and the urban area received oxygen and sulfur heterocyclic aromatic compounds most seriously. In Beijing, the degree of contamination by oxygen and sulfur heterocyclic aromatic compounds in the north surface soil was higher than that in the south. There were preferable linear correlations between the concentration of dibenzofuran series and fluorene series, as well as the concentration of dibenzothiophene series and dibenzofuran series. The oxygen and sulfur heterocyclic aromatic compounds in the surface soil were mainly derived from combustion products of oil and coal and direct input of mineral oil, etc. There were some variations in pollution sources of different environmental function zones.

  15. The Feasibility of Wood and its Derivatives as a Bicycle Frame Building Material

    OpenAIRE

    BRENT TAYLOR, NICHOLAS

    2016-01-01

    [EN] ABSTRACT Nicholas Brent Taylor: The Feasibility of Wood and its Derivatives as a Bicycle Frame Building Material The bicycle is often considered as one of the most important inventions of all time. In addition, it is the most efficient form of human transport in the world. It is non pollutant, uses no fuel other than human power and its carbon footprint is neutralised in a short time. Today, faced with the threat of global warming brought about by fossil fuels, countries such as De...

  16. Action of bicyclic isoxazole GABA analogues on GABA transporters and its relation to anticonvulsant activity

    DEFF Research Database (Denmark)

    Bolvig, T; Larsson, O M; Pickering, D S

    1999-01-01

    The inhibitory action of bicyclic isoxazole gamma-aminobutyric acid (GABA) analogues and their 4,4-diphenyl-3-butenyl (DPB) substituted derivatives has been investigated in cortical neurones and astrocytes as well as in human embryonic kidney (HEK 293) cells transiently expressing either mouse GA...... anticonvulsant activity, lack of proconvulsant activity and the ability of THPO to increase extracellular GABA concentration, indicate that these bicyclic isoxazole GABA analogues and their DPB derivatives may be useful lead structures in future search for new antiepileptic drugs....

  17. Modelling mode choice in short trips - shifting from car to bicycle

    DEFF Research Database (Denmark)

    Halldórsdóttir, Katrín; Christensen, Linda; Jensen, Thomas Christian

    2011-01-01

    -economic variables of a representative sample of the population. The investigated sample includes 11,072 observations. The model considers five alternatives (i.e., car driver, car passenger, public transport, walk and obviously bike), for which level of service variables are calculated through assignment procedures...... relevance of the cost for short trips. Expectedly, the selection of bicycle as mode for short trips is positively related to owning a bicycle and negatively linked to owning one or more cars. Urban density has also positive correlation with the selection of sustainable transport modes....

  18. Device and method to determine perineal artery occlusion during road bicycling.

    Science.gov (United States)

    Parthiban, Sujeeth; Hotaling, James M; Ohlander, Samuel J; Baftiri, Amit P; Freels, Sally; Niederberger, Craig S

    2014-01-01

    Greater than 60 million American men who ride bicycles are at risk of developing erectile dysfunction. One possible reason is occlusion of the perineal arteries. Researchers relied on indirect methods and stationary models to study this problem. We developed a novel system to quantify occlusion among bicycle riders during a road bike ride. Our verification and validation activities show that this system can be safely used on human subjects to measure perineal artery occlusion. The method described in this paper provides a valuable tool to the researchers to study or to develop new solutions that alleviate this problem. The outcomes of these efforts will help millions of cyclists worldwide.

  19. Electrochemical and Theoretical Study of a New Series of Bicyclic Oxazaborines

    Czech Academy of Sciences Publication Activity Database

    Mikysek, T.; Kvapilová, Hana; Josefík, F.; Ludvík, Jiří

    2016-01-01

    Roč. 49, č. 1 (2016), s. 178-187 ISSN 0003-2719 R&D Projects: GA MŠk LD14129 Grant - others:GA MŠk(CZ) CZ.1.07/2.3.00/30.0021 Institutional support: RVO:61388955 Keywords : Boron heterocycles * density functional theory * electrochemistry Subject RIV: CG - Electrochemistry Impact factor: 1.150, year: 2016

  20. What Factors Explain Bicycling and Walking for Commuting by ELSA-Brasil Participants?

    Science.gov (United States)

    de Matos, Sheila Maria Alvim; Pitanga, Francisco José Gondim; Almeida, Maria da Conceição C; Queiroz, Ciro Oliveira; Dos Santos, Clarice Alves; de Almeida, Rogerio Tosta; da Silva, Ianne Tayrine Martins; Griep, Rosane Harter; Amorim, Leila Denise Alves Ferreira; Patrão, Ana Luísa; Aquino, Estela M L

    2018-03-01

    To analyze the factors associated with commuting by bicycling and walking in adult participants from ELSA-Brasil (Longitudinal Study of Adult Health). Cross-sectional. Six teaching/research institutions throughout Brazil. A total of 15 105 civil servants. Commuting by bicycling and walking was analyzed using the long-form International Physical Activity Questionnaire. A hierarchical model containing possible factors associated with commuting by bicycling and walking was constructed. Crude and adjusted odds ratios were calculated using multinomial logistic regression. Considering the 2 forms of commuting, 66% of the participants were being considered inactive or insufficiently active. In women, being "heavier," feeling unsafe practicing physical activity, and being a former smoker were factors negatively associated with commuting by bicycling and walking. In men, active commuting was less common among those who were overweight or had abdominal obesity, those with a negative perception of safety, and those reporting that there was nowhere suitable in the neighborhood to practice physical activity. Obesity and negative perceptions in the neighborhood are associated with inactive or insufficiently active commuting. The relevance of this finding for public health is reinforce developing policies aimed at promoting health in Brazil and in other countries with similar characteristics.

  1. The Effects of Prompting and Reinforcement on Safe Behavior of Bicycle and Motorcycle Riders

    Science.gov (United States)

    Okinaka, Takeru; Shimazaki, Tsuneo

    2011-01-01

    A reversal design was used to evaluate the effects of vocal and written prompts as well as reinforcement on safe behavior (dismounting and walking bicycles or motorcycles on a sidewalk) on a university campus. Results indicated that an intervention that consisted of vocal and written prompts and reinforcement delivered by security guards was…

  2. 'Cycle thieves, we are watching you': impact of a simple signage intervention against bicycle theft.

    Directory of Open Access Journals (Sweden)

    Daniel Nettle

    Full Text Available Bicycle theft is a serious problem in many countries, and there is a lack of evidence concerning effective prevention strategies. Displaying images of 'watching eyes' has been shown to make people behave in more socially desirable ways in a number of settings, but it is not yet clear if this effect can be exploited for purposes of crime prevention. We report the results of a simple intervention on a university campus where signs featuring watching eyes and a related verbal message were displayed above bicycle racks.We installed durable signs at three locations which had experienced high levels of bicycle theft, and used the rest of the university campus as a control location. Reported thefts were monitored for 12 months before and after the intervention. Bicycle thefts decreased by 62% at the experimental locations, but increased by 65% in the control locations, suggesting that the signs were effective, but displaced offending to locations with no signs. The Odds Ratio for the effect of the intervention was 4.28 (95% confidence interval 2.04-8.98, a large effect compared to other place-based crime prevention interventions.The effectiveness of this extremely cheap and simple intervention suggests that there can be considerable crime-reduction benefits to engaging the psychology of surveillance, even in the absence of surveillance itself. Simple interventions for high-crime locations based on this principle should be considered as an adjunct to other measures, although a possible negative consequence is displacement of offending.

  3. 'Cycle thieves, we are watching you': impact of a simple signage intervention against bicycle theft.

    Science.gov (United States)

    Nettle, Daniel; Nott, Kenneth; Bateson, Melissa

    2012-01-01

    Bicycle theft is a serious problem in many countries, and there is a lack of evidence concerning effective prevention strategies. Displaying images of 'watching eyes' has been shown to make people behave in more socially desirable ways in a number of settings, but it is not yet clear if this effect can be exploited for purposes of crime prevention. We report the results of a simple intervention on a university campus where signs featuring watching eyes and a related verbal message were displayed above bicycle racks. We installed durable signs at three locations which had experienced high levels of bicycle theft, and used the rest of the university campus as a control location. Reported thefts were monitored for 12 months before and after the intervention. Bicycle thefts decreased by 62% at the experimental locations, but increased by 65% in the control locations, suggesting that the signs were effective, but displaced offending to locations with no signs. The Odds Ratio for the effect of the intervention was 4.28 (95% confidence interval 2.04-8.98), a large effect compared to other place-based crime prevention interventions. The effectiveness of this extremely cheap and simple intervention suggests that there can be considerable crime-reduction benefits to engaging the psychology of surveillance, even in the absence of surveillance itself. Simple interventions for high-crime locations based on this principle should be considered as an adjunct to other measures, although a possible negative consequence is displacement of offending.

  4. Validity of a device designed to measure braking power in bicycle disc brakes.

    Science.gov (United States)

    Miller, Matthew C; Fink, Philip W; Macdermid, Paul William; Perry, Blake G; Stannard, Stephen R

    2017-07-21

    Real-world cycling performance depends not only on exercise capacities, but also on efficiently traversing the bicycle through the terrain. The aim of this study was to determine if it was possible to quantify the braking done by a cyclist in the field. One cyclist performed 408 braking trials (348 on a flat road; 60 on a flat dirt path) over 5 days on a bicycle fitted with brake torque and angular velocity sensors to measure brake power. Based on Newtonian physics, the sum of brake work, aerodynamic drag and rolling resistance was compared with the change in kinetic energy in each braking event. Strong linear relationships between the total energy removed from the bicycle-rider system through braking and the change in kinetic energy were observed on the tar-sealed road (r 2  = 0.989; p brake torque and angular velocity sensors are valid for calculating brake power on the disc brakes of a bicycle in field conditions. Such a device may be useful for investigating cyclists' ability to traverse through various terrains.

  5. DEVELOPMENT OF AN ELECTRIC BICYCLE FOR A SHARING SYSTEM IN PRAGUE

    Directory of Open Access Journals (Sweden)

    William Deleenheer

    2017-12-01

    Full Text Available By means of a development of an e-bike sharing system the Electromobility Project wants to provide an alternative way of comfortable transportation for students and staff of the CTU, primarily to commute between different campuses. The research for this project contains at least three different fields of study, namely electric vehicle and docking station development, intelligent transport systems and management and economics of transportation and telecommunication. After briefly stating general requirements for the sharing system, this paper focuses on the development of the electric bicycle. First an ideal bike design is defined. Then necessary motor power and battery capacity are calculated by estimating characteristics of cycling in Prague. A prototype was developed by converting a normal bicycle to an electric bicycle. Being equipped with devices for e-bike monitoring, controlling and data recording for a post trip analysis, this prototype is also intended to have an educational value for future students in the project. Results consist of an electrical bicycle configuration that matches the requirements and a sketch of an ideal e-bike for this project.

  6. Tertiary Student Attitudes to Bicycle Commuting in a Regional Australian University

    Science.gov (United States)

    Whannell, Patricia; Whannell, Robert; White, Richard

    2012-01-01

    Purpose: The purpose of this paper is to provide executive management at a regional university with empirical data to justify, or otherwise, a substantial outlay of funds to support bicycle commuting as a viable strategy for the reduction of traffic congestion. Design/methodology/approach: A custom designed questionnaire was completed by 270…

  7. Modeling Mixed Bicycle Traffic Flow: A Comparative Study on the Cellular Automata Approach

    Directory of Open Access Journals (Sweden)

    Dan Zhou

    2015-01-01

    Full Text Available Simulation, as a powerful tool for evaluating transportation systems, has been widely used in transportation planning, management, and operations. Most of the simulation models are focused on motorized vehicles, and the modeling of nonmotorized vehicles is ignored. The cellular automata (CA model is a very important simulation approach and is widely used for motorized vehicle traffic. The Nagel-Schreckenberg (NS CA model and the multivalue CA (M-CA model are two categories of CA model that have been used in previous studies on bicycle traffic flow. This paper improves on these two CA models and also compares their characteristics. It introduces a two-lane NS CA model and M-CA model for both regular bicycles (RBs and electric bicycles (EBs. In the research for this paper, many cases, featuring different values for the slowing down probability, lane-changing probability, and proportion of EBs, were simulated, while the fundamental diagrams and capacities of the proposed models were analyzed and compared between the two models. Field data were collected for the evaluation of the two models. The results show that the M-CA model exhibits more stable performance than the two-lane NS model and provides results that are closer to real bicycle traffic.

  8. Road safety and bicycle usage impacts of unbundling vehicular and cycle traffic in Dutch urban networks

    NARCIS (Netherlands)

    Schepers, Paul; Heinen, Eva; Methorst, Rob; Wegman, Fred

    2013-01-01

    Bicycle-motor vehicle crashes are concentrated along distributor roads where cyclists are exposed to greater volumes of high-speed motorists than they would experience on access roads. This study examined the road safety impact of network-level separation of vehicular and cycle traffic in Dutch

  9. Road safety and bicycle usage impacts of unbundling vehicular and cycle traffic in Dutch urban networks.

    NARCIS (Netherlands)

    Schepers, P. Heinen, E. Methorst, R. & Wegman, F.

    2015-01-01

    Bicycle-motor vehicle crashes are concentrated along distributor roads where cyclists are exposed to greater volumes of high-speed motorists than they would experience on access roads. This study examined the road safety impact of network-level separation of vehicular and cycle traffic in Dutch

  10. 76 FR 52046 - Final Policy Statement on the Eligibility of Pedestrian and Bicycle Improvements Under Federal...

    Science.gov (United States)

    2011-08-19

    ... important for pedestrian comfort and safety. The most successful and useful public transportation systems... could take light rail, a bus, or ride a bike.'' \\4\\ As the Secretary further described, ``livable...; (G) Eligible Activities; (H) Bicycle Sharing Programs; (I) Planning Issues; (J) Safety Concerns; (K...

  11. 77 FR 60050 - Special Regulations; Areas of the National Park System, Saguaro National Park, Bicycling

    Science.gov (United States)

    2012-10-02

    ... hiking and equestrian trail that originates at the Loma Alta Trailhead and travels east through the..., including hiking, equestrian, and bicycle use. Shortly after acquiring the land, the NPS closed the route to... leadership after an adequate analysis of the benefits, impacts, and economic cost of alternative courses of...

  12. 77 FR 12761 - Special Regulations; Areas of the National Park System, Saguaro National Park, Bicycle Route

    Science.gov (United States)

    2012-03-02

    ..., preserve, and interpret the monument's resources, and to provide for education and benefit to the public... worldwide as an icon of the American Southwest. The Hope Camp Trail is a 2.8 mile long hiking and equestrian... the route to be used for recreational purposes, including hiking, equestrian and bicycle use. Shortly...

  13. Optimal Test Characteristics for Maximal Anaerobic Work on the Bicycle Ergometer

    Science.gov (United States)

    Katch, Victor; And Others

    1977-01-01

    Data from two separate experiments conducted to ascertain the optimum protocol for a maximum anaerobic work output test on the bicycle ergometer indicated that the test duration needs to be approximately forty seconds and the optimal frictional resistance five to six kilograms. (MB)

  14. Effect of bicycle saddle designs on the pressure to the perineum of the bicyclist.

    Science.gov (United States)

    Lowe, Brian D; Schrader, Steven M; Breitenstein, Michael J

    2004-06-01

    Increasing awareness of an association between bicycling and male sexual dysfunction has led to the appearance of a variety of bicycle saddles that share the design objective of reducing pressure in the groin of the cyclist by removal of the narrow protruding nose of the saddle. This study compared three of these saddle designs to a traditional sport/road racing saddle with a narrow protruding nose in terms of pressure in the region of the perineum (groin) of the cyclist. Saddle, pedal, and handlebar contact pressure were measured from 33 bicycle police patrol officers pedaling a stationary bicycle at a controlled cadence and workload. Pressure was characterized over the saddle as a whole and over a region of the saddle assumed to represent pressure on the cyclist's perineum located anteriorly to the ischial tuberosities. The traditional sport/racing saddle was associated with more than two times the pressure in the perineal region than the saddles without a protruding nose (P perineum of the bicyclist.

  15. Bicycle Facilities That Address Safety, Crime, and Economic Development: Perceptions from Morelia, Mexico

    Directory of Open Access Journals (Sweden)

    Inés Alveano-Aguerrebere

    2017-12-01

    Full Text Available México is a developing nation and, in the city of Morelia, the concept of the bicyclist as a road user appeared only recently in the Municipal Traffic Regulations. Perhaps the right bicycle infrastructure could address safety, crime, and economic development. To identify the best infrastructure, six groups in Morelia ranked and commented on pictures of bicycle environments that exist in bicycle-friendly nations. Perceptions about bike paths, but only those with impossible-to-be-driven-over solid barriers, were associated with safety from crashes, lowering crime, and contributing to economic development. Shared use paths were associated with lowering the probability of car/bike crashes but lacked the potential to deter crime and foster the local economy. Joint bus and bike lanes were associated with lower safety because of the unwillingness by Mexican bus drivers to be courteous to bicyclists. Gender differences about crash risk biking in the road with the cars (6 best/0 worst scenario were statistically significant (1.4 for male versus 0.69 for female; p < 0.001. For crashes, crime, and economic development, perceptions about bicycle infrastructure were different in this developing nation perhaps because policy, institutional context, and policing (ticketing for unlawful parking are not the same as in a developed nation. Countries such as Mexico should consider building cycle tracks with solid barriers to address safety, crime, and economic development.

  16. Bicycle Facilities That Address Safety, Crime, and Economic Development: Perceptions from Morelia, Mexico

    Science.gov (United States)

    Alveano-Aguerrebere, Inés; Farvid, Maryam; Lusk, Anne

    2017-01-01

    México is a developing nation and, in the city of Morelia, the concept of the bicyclist as a road user appeared only recently in the Municipal Traffic Regulations. Perhaps the right bicycle infrastructure could address safety, crime, and economic development. To identify the best infrastructure, six groups in Morelia ranked and commented on pictures of bicycle environments that exist in bicycle-friendly nations. Perceptions about bike paths, but only those with impossible-to-be-driven-over solid barriers, were associated with safety from crashes, lowering crime, and contributing to economic development. Shared use paths were associated with lowering the probability of car/bike crashes but lacked the potential to deter crime and foster the local economy. Joint bus and bike lanes were associated with lower safety because of the unwillingness by Mexican bus drivers to be courteous to bicyclists. Gender differences about crash risk biking in the road with the cars (6 best/0 worst scenario) were statistically significant (1.4 for male versus 0.69 for female; p < 0.001). For crashes, crime, and economic development, perceptions about bicycle infrastructure were different in this developing nation perhaps because policy, institutional context, and policing (ticketing for unlawful parking) are not the same as in a developed nation. Countries such as Mexico should consider building cycle tracks with solid barriers to address safety, crime, and economic development. PMID:29271873

  17. Association between neighborhood walkability and GPS-measured walking, bicycling and vehicle time in adolescents

    DEFF Research Database (Denmark)

    Carlson, Jordan A.; Saelens, Brian E.; Kerr, Jacqueline

    2015-01-01

    , intersection density, retail density, entertainment density and walkability were derived using GIS. Minutes/day of walking, bicycling and vehicle time were derived from processing algorithms applied to GPS. Accelerometers estimated total daily moderate-to-vigorous physical activity (MVPA). Models were adjusted...

  18. Sensor design for outdoor racing bicycle field testing for human vibration comfort evaluation

    International Nuclear Information System (INIS)

    Vanwalleghem, Joachim; De Baere, Ives; Van Paepegem, Wim; Loccufier, Mia

    2013-01-01

    This paper is concerned with the vibrational comfort evaluation of the cyclist when cycling a rough surface. Outdoor comfort tests have so far only been done through instrumenting the bicycle with accelerometers. This work instruments a racing bicycle with custom-made contact force sensors and velocity sensors to acquire human comfort through the absorbed power method. Comfort evaluation is assessed at the hand–arm and seat interface of the cyclist with the bicycle. By means of careful finite-element analysis for designing the force gauges at the handlebar and the seat combined with precise calibration of both force and velocity sensors, all sensors have proven to work properly. Initial field tests are focused on the proper functioning of the designed sensors and their suitability for vibration comfort measurements. Tests on a cobblestone road reveal that the outcome of the absorbed power values is within the same range as those from laboratory tests found in the literature. This sensor design approach for outdoor testing with racing bicycles may give a new interpretation on evaluating the cyclist's comfort since the vibrational load is not only quantified in terms of acceleration but also in terms of force and velocity at the bicycle–cyclist contact points. (paper)

  19. The Dutch Bicycle Master Plan and road safety : measures to be taken.

    NARCIS (Netherlands)

    Noordzij, P.C. & Blokpoel, A.

    1998-01-01

    The Bicycle Master Plan was launched in 1990 and concluded in 1996. To mark its conclusion, a study was carried out to assess developments in road safety for cyclists. An overview of future measures was also compiled. Since 1950, there have been three broad periods: (1) 1950-1975: an increase in the

  20. Environmental and social life cycle assessment of bamboo bicycle frames made in Ghana

    NARCIS (Netherlands)

    Agyekum, Eric Ofori; Fortuin, K.P.J.; Harst-Wintraecken, van der E.J.M.

    2017-01-01

    This case study assessed the environmental and social impact of bicycle frames made from wild Ghanaian bamboo. The environmental life cycle assessment (LCA) of the bamboo frame was compared to the LCA results of an aluminium frame and a steel frame. The results show that the overall environmental

  1. Bicycle-Related Shoulder Injuries: Etiology and the Need for Protective Gear.

    Science.gov (United States)

    Goldstein, Yariv; Dolkart, Oleg; Kaufman, Ehud; Amar, Eyal; Sharfman, Zachary T; Rath, Ehud; Mozes, Gavriel; Maman, Eran

    2016-01-01

    The popularity of bicycle riding for recreation, exercise and transportation has grown enormously in recent years, which has led to an increased incidence of bicycle-related injuries. While these injuries involve mainly the musculoskeletal system, data on shoulder-specific injuries incurred while bike riding are lacking. Classifying these shoulder injuries may provide insight and assistance in the creation and implementation of effective protective gear and measures. To investigate the types and mechanisms of shoulder injuries among cyclists. This study retrospectively examined all cyclists who incurred shoulder injuries while riding and were admitted to the emergency department and shoulder clinic between January 2008 and November 2013. The study included 157 subjects with various bicycle-related shoulder injuries treated with either conservative or surgical measures. Eighty-four percent of injuries were caused by a direct blow to the shoulder, 7% by falling on an outstretched hand, 6% were traction injuries, and 3% were due to hyperabduction. Nine different clinical types of injury were observed; the most common injuries were clavicle fractures (32%), followed by acromioclavicular joint dislocations (22%), rotator cuff tears (22%), and humeral fractures (8%). Fifty-one percent of subjects were managed with conservative care and the remaining patients required surgical interventions. Shoulder injuries incurred while riding a bicycle span the entire spectrum of shoulder injuries and often result in debilitating conditions. Although the use of helmets is increasing, there is currently no effective protective gear or measures to prevent riders from suffering shoulder injuries.

  2. Aminocyclopentanols as sugar mimics. Synthesis from unsaturated bicyclic lactones by Overman rearrangement

    DEFF Research Database (Denmark)

    Bøjstrup, Marie; Fanefjord, Mette; Lundt, Inge

    2007-01-01

    Bicyclic cyclopentane lactones, prepared from bromodeoxyaldonolactones, were transformed into aminocyclopentanols with an Overman rearrangement as the key step. Two of the compounds prepared, 7 and 19, were found to be good inhibitors of jack bean alpha-mannosidase and beta-D-N-acetylglucosaminid...

  3. Evaluation of a promotional strategy to increase bicycle helmet use by children.

    Science.gov (United States)

    Parkin, P C; Spence, L J; Hu, X; Kranz, K E; Shortt, L G; Wesson, D E

    1993-04-01

    Bicycle-related head injuries are an important cause of death and disability, despite the availability of helmets. The objective of this study was to evaluate the effectiveness of a school-based bicycle helmet promotion program in increasing helmet use by children while controlling for secular trends. Two high-income and two low-income schools in an urban Canadian community were selected to receive a bicycle helmet promotion intervention, with the remaining 18 schools serving as controls. Approximately 1800 observations of bicycling children were made at randomly selected observational sites 2 to 5 months after the intervention to assess changes in behavior. Helmet use at all observation sites tripled from 3.4% (1990, preintervention) to 16% (1991, postintervention). In the high-income intervention area, observed helmet use rose dramatically from 4% to 36% in contrast to the more modest increase in the high-income control area from 4% to 15%. In the low-income intervention area, there was a modest increase from 1% to 7%, but it did not differ from the increase in the low-income control area from 3% to 13%. The program was highly successful in children of high-income families but not in children of low-income families. Developing strategies for low-income families remains a priority.

  4. The Bicycle Illusion: Sidewalk Science Informs the Integration of Motion and Shape Perception

    Science.gov (United States)

    Masson, Michael E. J.; Dodd, Michael D.; Enns, James T.

    2009-01-01

    The authors describe a new visual illusion first discovered in a natural setting. A cyclist riding beside a pair of sagging chains that connect fence posts appears to move up and down with the chains. In this illusion, a static shape (the chains) affects the perception of a moving shape (the bicycle), and this influence involves assimilation…

  5. Bicycle Facilities That Address Safety, Crime, and Economic Development: Perceptions from Morelia, Mexico.

    Science.gov (United States)

    Alveano-Aguerrebere, Inés; Javier Ayvar-Campos, Francisco; Farvid, Maryam; Lusk, Anne

    2017-12-22

    México is a developing nation and, in the city of Morelia, the concept of the bicyclist as a road user appeared only recently in the Municipal Traffic Regulations. Perhaps the right bicycle infrastructure could address safety, crime, and economic development. To identify the best infrastructure, six groups in Morelia ranked and commented on pictures of bicycle environments that exist in bicycle-friendly nations. Perceptions about bike paths, but only those with impossible-to-be-driven-over solid barriers, were associated with safety from crashes, lowering crime, and contributing to economic development. Shared use paths were associated with lowering the probability of car/bike crashes but lacked the potential to deter crime and foster the local economy. Joint bus and bike lanes were associated with lower safety because of the unwillingness by Mexican bus drivers to be courteous to bicyclists. Gender differences about crash risk biking in the road with the cars (6 best/0 worst scenario) were statistically significant (1.4 for male versus 0.69 for female; p < 0.001). For crashes, crime, and economic development, perceptions about bicycle infrastructure were different in this developing nation perhaps because policy, institutional context, and policing (ticketing for unlawful parking) are not the same as in a developed nation. Countries such as Mexico should consider building cycle tracks with solid barriers to address safety, crime, and economic development.

  6. Biomechanical Evaluation of an Electric Power-Assisted Bicycle by a Musculoskeletal Model

    Science.gov (United States)

    Takehara, Shoichiro; Murakami, Musashi; Hase, Kazunori

    In this study, we construct an evaluation system for the muscular activity of the lower limbs when a human pedals an electric power-assisted bicycle. The evaluation system is composed of an electric power-assisted bicycle, a numerical simulator and a motion capture system. The electric power-assisted bicycle in this study has a pedal with an attached force sensor. The numerical simulator for pedaling motion is a musculoskeletal model of a human. The motion capture system measures the joint angles of the lower limb. We examine the influence of the electric power-assisted force on each muscle of the human trunk and legs. First, an experiment of pedaling motion is performed. Then, the musculoskeletal model is calculated by using the experimental data. We discuss the influence on each muscle by electric power-assist. It is found that the muscular activity is decreased by the electric power-assist bicycle, and the reduction of the muscular force required for pedaling motion was quantitatively shown for every muscle.

  7. Investigation of Influential Factors for Bicycle Crashes Using a Spatiotemporal Model

    Science.gov (United States)

    Gill, G.; Sakrani, T.; Cheng, W.; Zhou, J.

    2017-09-01

    Despite the numerous potential advantages of indulging in bicycling, such as elevation of health and environment along with mitigation of congestion, the cyclists are a vulnerable group of commuters which is exposed to safety risks. This study aims to investigate the explanatory variables at transportation planning level which have a significant impact on the bicycle crashes. To account for the serial changes around the built environment, the linear time trend as well as time-varying coefficients are utilized for the covariates. These model modifications help account for the variations in the environment which may escape the incorporated variables due to lack of robustness in data. Also, to incorporate the interaction of roadway, demographic, and socioeconomic features within a Traffic Analysis Zone (TAZ), with the bicycle crashes of that area, a spatial correlation is integrated. This spatial correlation accounts for the spatially structured random effects which capture the unobserved heterogeneity and add towards building more comprehensive model with relatively precise estimates. Two different age groups, the student population in the TAZs, the presence of arterial roads and bike lanes, were observed to be statistically significant variables related with bicycle crashes. These observations will guide the transportation planning organizations which focus on the entity of TAZ while developing policies. The results of the current study establish a quantifies relationship between the significant factors and the crash count which will enable the planners to choose the most cost-efficient, yet most productive, factors which needs to be addressed for mitigation of crashes.

  8. Serotonergic 5-HT6 Receptor Antagonists: Heterocyclic Chemistry and Potential Therapeutic Significance.

    Science.gov (United States)

    Bali, Alka; Singh, Shalu

    2015-01-01

    The serotonin 5-HT(6) receptor (5- HT(6)R) is amongst the recently discovered serotonergic receptors with almost exclusive localization in the brain. Hence, this receptor is fast emerging as a promising target for cognition enhancement in central nervous system (CNS) diseases such as Alzheimer's disease (cognitive function), obesity, schizophrenia and anxiety. The last decade has seen a surge of literature reports on the functional role of this receptor in learning and memory processes and investigations related to the chemistry and pharmacology of 5-HT(6) receptor ligands, especially 5- HT(6) receptor antagonists. Studies show the involvement of multiple neurotransmitter systems in cognitive enhancement by 5-HT(6)R antagonists including cholinergic, glutamatergic, and GABAergic systems. Several of the 5-HT(6)R ligands are indole based agents bearing structural similarity to the endogenous neurotransmitter serotonin. Based on the pharmacophoric models proposed for these agents, drug designing has been carried out incorporating various heterocyclic replacements for the indole nucleus. In this review, we have broadly summarized the medicinal chemistry and current status of this fairly recent class of drugs along with their potential therapeutic applications.

  9. Construction of porous cationic frameworks by crosslinking polyhedral oligomeric silsesquioxane units with N-heterocyclic linkers

    Science.gov (United States)

    Chen, Guojian; Zhou, Yu; Wang, Xiaochen; Li, Jing; Xue, Shuang; Liu, Yangqing; Wang, Qian; Wang, Jun

    2015-06-01

    In fields of materials science and chemistry, ionic-type porous materials attract increasing attention due to significant ion-exchanging capacity for accessing diversified applications. Facing the fact that porous cationic materials with robust and stable frameworks are very rare, novel tactics that can create new type members are highly desired. Here we report the first family of polyhedral oligomeric silsesquioxane (POSS) based porous cationic frameworks (PCIF-n) with enriched poly(ionic liquid)-like cationic structures, tunable mesoporosities, high surface areas (up to 1,025 m2 g-1) and large pore volumes (up to 0.90 cm3 g-1). Our strategy is designing the new rigid POSS unit of octakis(chloromethyl)silsesquioxane and reacting it with the rigid N-heterocyclic cross-linkers (typically 4,4‧-bipyridine) for preparing the desired porous cationic frameworks. The PCIF-n materials possess large surface area, hydrophobic and special anion-exchanging property, and thus are used as the supports for loading guest species PMo10V2O405- the resultant hybrid behaves as an efficient heterogeneous catalyst for aerobic oxidation of benzene and H2O2-mediated oxidation of cyclohexane.

  10. Synthesis of pyridine and isoquinoline labelled with 14C on the nitrogen heterocycle

    International Nuclear Information System (INIS)

    Robveille, Jacques

    1985-01-01

    This research thesis addresses the synthesis of derivatives of pyridine and isoquinoline labelled with carbon 14 ( 14 C) in the nitrogenated heterocycle as these compounds are of biological and pharmacological interest. The author aimed at developing rather general synthesis schemes which could be easily applied to the synthesis of radioactive compounds, and could produce, through a given synthesis way, the largest as possible family of differently substituted compounds. Different sources for labelled pyridine and isoquinoline have been used: dioxo-1,5 or their corresponding dioxins, substituted pentadienoic acids, derivatives of acrylic acid, and derivatives of cinnamic acid. Thus, three different synthesis processes have been developed to obtain 14 C labelled pyridine, and one of them is applied to the preparation of 14 C labelled isoquinoline. These synthesis processes can have a very general application, and allow different 14 C labelling positions to be envisaged. The possibility to obtain the same compounds but labelled with tritium can also be envisaged to obtain much higher specific activities [fr

  11. Fused Heterocyclic Compounds as Potent Indoleamine-2,3-dioxygenase 1 Inhibitors.

    Science.gov (United States)

    Panda, Subhankar; Roy, Ashalata; Deka, Suman Jyoti; Trivedi, Vishal; Manna, Debasis

    2016-12-08

    Uncontrolled metabolism of l-tryptophan (l-Trp) in the immune system has been recognized as a critical cellular process in immune tolerance. Indoleamine 2,3-dioxygenase 1 (IDO1) enzyme plays an important role in the metabolism of a local l-Trp through the kynurenine pathway in the immune systems. In this regard, IDO1 has emerged as a therapeutic target for the treatment of diseases that are associated with immune suppression like chronic infections, cancer, and others. In this study, we synthesized a series of pyridopyrimidine, pyrazolopyranopyrimidine, and dipyrazolopyran derivatives. Further lead optimizations directed to the identification of potent compounds, 4j and 4l (IC 50 = 260 and 151 nM, respectively). These compounds also exhibited IDO1 inhibitory activities in the low nanomolar range in MDA-MB-231 cells with very low cytotoxicity. Stronger selectivity for the IDO1 enzyme (>300-fold) over tryptophan 2,3-dioxygenase (TDO) enzyme was also observed for these compounds. Hence, these fused heterocyclic compounds are attractive candidates for the advanced study of IDO1-dependent cellular function and immunotherapeutic applications.

  12. Dietary exposure to heterocyclic amines in high-temperature cooked meat and fish in Malaysia.

    Science.gov (United States)

    Jahurul, M H A; Jinap, S; Ang, S J; Abdul-Hamid, A; Hajeb, P; Lioe, H N; Zaidul, I S M

    2010-08-01

    The intake of heterocyclic amines is influenced by the amount and type of meat and fish ingested, frequency of consumption, cooking methods, cooking temperature, and duration of cooking. In this study, the dietary intake of heterocyclic amines in Malaysia and their main sources were investigated. Forty-two samples of meat and fish were analysed by high-performance liquid chromatography with photodiode array detector to determine the concentration of the six predominant heterocyclic amines, namely: 2-amino-3-methylimidazo[4,5-f] quinoline (IQ), 2-amino-3,4-dimethylimidazo[4,5-f] quinoline(MeIQ), 2-amino-3,8-dimethylimidazo[4,5-f] quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5-f] quinoxaline (4,8-DiMeIQx), 2-amino-3,7,8-trimethylimidazo[4,5-f] quinoxaline (7,8-DiMeIQx), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Dietary intake data were obtained using a food-frequency questionnaire when interviewing 600 Malaysian respondents. The level of total heterocyclic amines in food samples studies ranged from not detected to 38.7 ng g(-1). The average daily intake level of heterocyclic amine was 553.7 ng per capita day(-1). The intake of PhIP was the highest, followed by MeIQx and MeIQ. The results reveal that fried and grilled chicken were the major dietary source of heterocyclic amines in Malaysia. However, the heterocyclic amine intake by the Malaysian population was lower than those reported from other regions.

  13. Determining the Optimal Layout Design for Public Bicycle System within the Attractive Scope of a Metro Station

    Directory of Open Access Journals (Sweden)

    Jingxu Chen

    2015-01-01

    Full Text Available Public bicycle acts as a seamless feeder mode in combination with the citywide public transit, as well as a competitor for the inner-city short trips. The primary objective of this study is to address the layout planning of public bicycle system within the attracted scope of a metro station. Based on the land use function, population, and bicycle mode share, bicycle rental stations are divided into three types, namely, the metro station, district station, and resident station, and later the quantity of bicycle facilities in each rental station is estimated. Then, the service stations are selected from these bicycle rental stations to provide the service of periodical bicycle redistribution. An improved immune algorithm is proposed to determine the number and locations of service stations and the optimal route options for the implement of redistributing strategy. Finally, a case study of Nanjing Tianyin Road metro station is conducted to illustrate the proposed model and clarify some of its implementation details.

  14. An Association Rule Based Method to Integrate Metro-Public Bicycle Smart Card Data for Trip Chain Analysis

    Directory of Open Access Journals (Sweden)

    De Zhao

    2018-01-01

    Full Text Available Smart card data provide valuable insights and massive samples for enhancing the understanding of transfer behavior between metro and public bicycle. However, smart cards for metro and public bicycle are often issued and managed by independent companies and this results in the same commuter having different identity tags in the metro and public bicycle smart card systems. The primary objective of this study is to develop a data fusion methodology for matching metro and public bicycle smart cards for the same commuter using historical smart card data. A novel method with association rules to match the data derived from the two systems is proposed and validation was performed. The results showed that our proposed method successfully matched 573 pairs of smart cards with an accuracy of 100%. We also validated the association rules method through visualization of individual metro and public bicycle trips. Based on the matched cards, interesting findings of metro-bicycle transfer have been derived, including the spatial pattern of the public bicycle as first/last mile solution as well as the duration of a metro trip chain.

  15. Componentes voláteis do café torrado. Parte I: compostos heterocíclicos Volatile components in roasted coffee. Part I: heterocyclic compounds

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Bastos De Maria

    1999-04-01

    Full Text Available A review of heterocyclic compounds in roasted coffee is presented. The contents, precursors and sensorial properties of furans, pyrroles, oxazoles, thiazoles, thiophenes, pyrazines and pyridines are discussed. The impact heterocyclic compounds of coffee aroma are described.

  16. Biking for Health: Results of a Pilot Randomized Controlled Trial Examining the Impact of a Bicycling Intervention on Lower-Income Adults.

    Science.gov (United States)

    Bernstein, Rebecca; Schneider, Robert; Welch, Whitney; Dressel, Anne; DeNomie, Melissa; Kusch, Jennifer; Sosa, Mirtha

    2017-08-01

    This pilot study tested the efficacy of a bicycling intervention targeting inactive, low-income, overweight adults on reducing perceived barriers to bicycling, increasing physical activity, and improving health. A nonblinded 2-site randomized controlled trial was conducted in Milwaukee, Wisconsin, in summer 2015. Participants included members from 1 largely Latino community and a second primarily African American neighborhood. A certified bicycling instructor led a 12-week bicycling intervention. Outcome measures including biking-related attitudes, self-reported physical activity, fitness as measured by the 6-minute step test, and biometric data were collected at baseline, 12 weeks, and 20 weeks. Thirty-eight participants completed the study. Barriers to bicycling declined significantly among intervention group participants at 12 weeks with some declines persisting to 20 weeks. Bicycling for leisure or non work transportation increased significantly more in the intervention than control group from baseline to 12 weeks but this difference attenuated by 20 weeks. Both groups increased their fitness between baseline and 12 weeks, with a trend towards greater gains in the bicycling intervention group. No significant change in biometric measurements was seen at either 12 weeks or 20 weeks. Despite the small study size, this bicycling intervention decreased perceived barriers to bicycling and increased bicycling activity in low-income minority participants. These findings support a larger-scale study to measure fitness and health changes from bicycling interventions.

  17. Severe bicycling injury risk factors in children and adolescents: a case-control study.

    Science.gov (United States)

    Hagel, Brent E; Romanow, Nicole T R; Enns, Nancy; Williamson, Jacqueline; Rowe, Brian H

    2015-05-01

    Bicycling is the most common cause of sports and recreation injury in children and adolescents; yet, there is limited evidence on the factors associated with severe bicycling injuries in youth. Case-control study of injured bicyclists less than 18 years old seen in seven emergency departments (EDs) from May 2008 to October 2010. Cases were bicyclists hospitalized after their ED visit (severe injury). Controls were bicyclists seen and discharged from the ED (non-severe injury). Personal, environmental, and crash characteristics were collected by interview. Injury data were collected from medical charts. Crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) from logistic regression were used to estimate the odds of hospitalization associated with risk factors. Multiple imputation techniques were employed to address missing data. There were 1470 participants including 119 cases. Those ages 13-17 had the highest proportion (23%) of severe injuries resulting from motor vehicle [MV] collision. In models including age, sex and MV collision, being male (OR: 2.02; 95% CI: 1.21-3.38), not wearing a helmet (OR: 2.18; 95% CI: 1.43-3.31) and MV collision (OR: 3.91; 95% CI: 2.26-6.78) were significant risk factors for severe injury. Riding on a paved surface (OR: 0.63; 95% CI: 0.41-0.97) and utilitarian (school, work) bicycling (OR: 0.44; 95% CI: 0.2-0.94) decreased injury risk. Results were similar, apart from utilitarian bicycling (OR: 0.49; 95% CI: 0.22-1.06), after imputation for missing data. Bicycle-MV collisions increase severe injury risk in youth, and adolescents are often injured in these events. This suggests separating bicyclists from MVs or traffic calming strategies could improve safety. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. An expert judgment model applied to estimating the safety effect of a bicycle facility.

    Science.gov (United States)

    Leden, L; Gårder, P; Pulkkinen, U

    2000-07-01

    This paper presents a risk index model that can be used for assessing the safety effect of countermeasures. The model estimates risk in a multiplicative way, which makes it possible to analyze the impact of different factors separately. Expert judgments are incorporated through a Bayesian error model. The variance of the risk estimate is determined by Monte-Carlo simulation. The model was applied to assess the safety effect of a new design of a bicycle crossing. The intent was to gain safety by raising the crossings to reduce vehicle speeds and by making the crossings more visible by painting them in a bright color. Before the implementations, bicyclists were riding on bicycle crossings of conventional Swedish type, i.e. similar to crosswalks but delineated by white squares rather than solid lines or zebra markings. Automobile speeds were reduced as anticipated. However, it seems as if the positive effect of this was more or less canceled out by increased bicycle speeds. The safety per bicyclist was still improved by approximately 20%. This improvement was primarily caused by an increase in bicycle flow, since the data show that more bicyclists at a given location seem to benefit their safety. The increase in bicycle flow was probably caused by the new layout of the crossings since bicyclists perceived them as safer and causing less delay. Some future development work is suggested. Pros and cons with the used methodology are discussed. The most crucial parameter to be added is probably a model describing the interaction between motorists and bicyclists, for example, how risk is influenced by the lateral position of the bicyclist in relation to the motorist. It is concluded that the interaction seems to be optimal when both groups share the roadway.

  19. Two-dimensional character of internal rotation of furfural and other five-member heterocyclic aromatic aldehydes

    Science.gov (United States)

    Bataev, Vadim A.; Pupyshev, Vladimir I.; Godunov, Igor A.

    2016-05-01

    The features of nuclear motion corresponding to the rotation of the formyl group (CHO) are studied for the molecules of furfural and some other five-member heterocyclic aromatic aldehydes by the use of MP2/6-311G** quantum chemical approximation. It is demonstrated that the traditional one-dimensional models of internal rotation for the molecules studied have only limited applicability. The reason is the strong kinematic interaction of the rotation of the CHO group and out-of-plane CHO deformation that is realized for the molecules under consideration. The computational procedure based on the two-dimensional approximation is considered for low lying vibrational states as more adequate to the problem.

  20. Microwave-Assisted Syntheses of Bioactive Seven-Membered, Macro-Sized Heterocycles and Their Fused Derivatives

    Directory of Open Access Journals (Sweden)

    Mohsine Driowya

    2016-08-01

    Full Text Available This review describes the recent advances in the microwave-assisted synthesis of 7-membered and larger heterocyclic compounds. Several types of reaction for the cyclization step are discussed: Ring Closing Metathesis (RCM, Heck and Sonogashira reactions, Suzuki-Miyaura cross-coupling, dipolar cycloadditions, multi-component reactions (Ugi, Passerini, etc. Green syntheses and solvent-free procedures have been introduced whenever possible. The syntheses discussed herein have been selected to illustrate the huge potential of microwave in the synthesis of highly functionalized molecules with potential therapeutic applications, in high yields, enhanced reaction rates and increased chemoselectivity, compared to conventional methods. More than 100 references from the recent literature are listed in this review.

  1. Mitsunobu mischief: Neighbor-directed histidine N(π)–alkylation provides access to peptides containing selectively functionalized imidazolium heterocycles

    Science.gov (United States)

    Qian, Wen-Jian

    2015-01-01

    There are few methodologies that yield peptides containing His residues with selective N(π), N(π)-bis-alkylated imidazole rings. We have found that, under certain conditions, on-resin Mitsunobu coupling of alcohols with peptides having a N(π)-alkylated His residue results in selective and high-yield alkylation of the imidazole N(π) nitrogen. The reaction requires the presence of a proximal phosphoric, carboxylic or sulfonic acid, and proceeds through an apparent intramolecular mechanism involving Mitsunobu intermediates. These transformations have particular application to phosphopeptides, where “charge masking” of one phosphoryl anionic charge by the cationic histidine imidazolium ion is now possible. This chemistry opens selective access to peptides containing differentially functionalized imidazolium heterocycles, which provide access to new classes of peptides and peptide mimetics. PMID:25739367

  2. Two-dimensional character of internal rotation of furfural and other five-member heterocyclic aromatic aldehydes.

    Science.gov (United States)

    Bataev, Vadim A; Pupyshev, Vladimir I; Godunov, Igor A

    2016-05-15

    The features of nuclear motion corresponding to the rotation of the formyl group (CHO) are studied for the molecules of furfural and some other five-member heterocyclic aromatic aldehydes by the use of MP2/6-311G** quantum chemical approximation. It is demonstrated that the traditional one-dimensional models of internal rotation for the molecules studied have only limited applicability. The reason is the strong kinematic interaction of the rotation of the CHO group and out-of-plane CHO deformation that is realized for the molecules under consideration. The computational procedure based on the two-dimensional approximation is considered for low lying vibrational states as more adequate to the problem. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Synthesis and Biological Activity Evaluation of Novel Heterocyclic Pleuromutilin Derivatives

    Directory of Open Access Journals (Sweden)

    Yunpeng Yi

    2017-06-01

    Full Text Available A series of pleuromutilin derivatives were synthesized by two synthetic procedures under mild reaction conditions and characterized by Nuclear Magnetic Resonance (NMR, Infrared Spectroscopy (IR, and High Resolution Mass Spectrometer (HRMS. Most of the derivatives with heterocyclic groups at the C-14 side of pleuromutilin exhibited excellent in vitro antibacterial activities against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA, methicillin-resistant Staphylococcus epidermidis (MRSE, and vancomycin-resistant Enterococcus (VRE in vitro antibacterial activity. The synthesized derivatives which contained pyrimidine rings, 3a, 3b, and 3f, displayed modest antibacterial activities. Compound 3a, the most active antibacterial agent, displayed rapid bactericidal activity and affected bacterial growth in the same manner as that of tiamulin fumarate. Moreover, molecular docking studies of 3a and lefamulin provided similar information about the interactions between the compounds and 50S ribosomal subunit. The results of the study show that pyrimidine rings should be considered in the drug design of pleuromutilin derivatives.

  4. The Effect of Novel Heterocyclic Compounds on Cryptococcal Biofilm

    Science.gov (United States)

    Korem, Maya; Kagan, Sarah

    2017-01-01

    Biofilm formation by microorganisms depends on their communication by quorum sensing, which is mediated by small diffusible signaling molecules that accumulate in the extracellular environment. During human infection, the pathogenic yeast Cryptococcus neoformans can form biofilm on medical devices, which protects the organism and increases its resistance to antifungal agents. The aim of this study was to test two novel heterocyclic compounds, S-8 (thiazolidinedione derivative, TZD) and NA-8 (succinimide derivative, SI), for their anti-biofilm activity against strains of Cryptococcus neoformans and Cryptococcus gattii. Biofilms were formed in a defined medium in 96-well polystyrene plates and 8-well micro-slides. The effect of sub-inhibitory concentrations of S-8 and NA-8 on biofilm formation was measured after 48 h by a metabolic reduction assay and by confocal laser microscopy analysis using fluorescent staining. The formation and development of cryptococcal biofilms was inhibited significantly by these compounds in concentrations below the minimum inhibitory concentration (MIC) values. These compounds may have a potential role in preventing fungal biofilm development on indwelling medical devices or even as a therapeutic measure after the establishment of biofilm. PMID:29371559

  5. Selected heterocyclic compounds as antioxidants. Synthesis and biological evaluation.

    Science.gov (United States)

    Tsolaki, E; Nobelos, P; Geronikaki, A; Rekka, E A

    2014-01-01

    Reactive oxygen species, oxidative stress, and oxidative damage are increasingly assigned important roles as harmful factors in pathological conditions and ageing. ROS are potentially reactive molecules derived from the reduction of molecular oxygen in the course of aerobic metabolism. ROS can also be produced through a variety of enzymes. Under normal circumstances, ROS concentrations are tightly controlled by physiological antioxidants. When excessively produced, or when antioxidants are depleted, ROS can impose oxidative damage to lipids, proteins, sugars and DNA. This reduction-oxidation imbalance, called oxidative stress, can subsequently contribute to the development and progression of tissue damage and play a role in the pathology of various diseases. An antioxidant is defined as "any substance that, when present at low concentrations compared with those of a substrate, significantly delays, prevents or removes oxidative damage to this target molecule". Despite evidence that oxidative damage contributes to a wide range of clinically important conditions, few antioxidants act as effective drugs in vivo. Inter alia, the difficulty of measuring antioxidant efficacy in vivo makes the interpretation of results from clinical trials difficult. A large number of synthetic compounds have been reported to possess antioxidant activity. Several of them derive from natural antioxidants, others have various structures. In this review, some of the most often reported classes of heterocyclic antioxidant compounds, as well as methods for evaluation of their antioxidant activity are discussed.

  6. Occurrence of heterocyclic amines in cooked meat products.

    Science.gov (United States)

    Puangsombat, Kanithaporn; Gadgil, Priyadarshini; Houser, Terry A; Hunt, Melvin C; Smith, J Scott

    2012-03-01

    Heterocyclic amines (HCAs), potent mutagens and a risk factor for human cancers, are produced in meats cooked at high temperature. The aim of this study was to determine the HCA content in cooked meat products (beef, chicken, pork, fish) prepared by various cooking methods (pan frying, oven broiling, and oven baking at 170 to 230°C) that are preferred by U.S. meat consumers. The primary HCAs in these samples were PhIP (2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine) (1.49-10.89ng/g), MeIQx (2-amino-3,8-dimethylimidazo [4,5-f]quinoxaline) (not detected-4.0ng/g), and DiMeIQx (2-amino-3,4,8-trimethyl-imidazo [4,5-f]quinoxaline) (not detected-3.57ng/g). Type and content of HCAs in cooked meat samples were highly dependent on cooking conditions. The total HCA content in well-done meat was 3.5 times higher than that of medium-rare meat. Fried pork (13.91ng/g) had higher levels of total HCAs than fried beef (8.92ng/g) and fried chicken (7.00ng/g). Among the samples, fried bacon contained the highest total HCA content (17.59ng/g). Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. On the radioprotective properties of heterocyclic nitrogenous compounds

    International Nuclear Information System (INIS)

    Rinaldi, R.; Bernard, Y.

    1964-01-01

    Continuing their study of the possible radioprotective properties of heterocyclic nitrogenous compounds, the authors study certain derivatives of imidazole and other compounds of similar structure. The results obtained showed: 1 - that the derivatives resulting from the presence in the imidazole ring of the mercapto, methyl, carbonyl, or benzyl groups are inactive: these substitutions appear to destroy the significant radioprotective activity of the imidazole, 2 - that benzimidazole, on the contrary, seems to possess highly interesting properties. The percentage of survivals obtained with mice treated with benzimidazole and exposed to lethal irradiation has encouraged the authors to undertake careful study of this substance, with a view to define optimum activity conditions, and to determine the mechanism responsible for its radioprotective action. Further on and so as to of clarify certain points that might give useful data concerning the mechanisms of action of radioprotective chemicals, in respect of each of the products the authors have studied: a - the action of these bodies on the internal temperature of mice, b - their radioprotective activity in vitro, in a solution of irradiated hemin. (authors) [fr

  8. Does the Effect of Micro-Environmental Factors on a Street's Appeal for Adults' Bicycle Transport Vary across Different Macro-Environments? An Experimental Study.

    Science.gov (United States)

    Mertens, Lieze; Van Cauwenberg, Jelle; Ghekiere, Ariane; Van Holle, Veerle; De Bourdeaudhuij, Ilse; Deforche, Benedicte; Nasar, Jack; Van de Weghe, Nico; Van Dyck, Delfien

    2015-01-01

    Characteristics of the physical environment can be classified into two broad categories: macro- ("raw" urban planning features influenced on a regional level) and micro- (features specifically within a streetscape influenced on a neighborhood level) environmental factors. In urban planning applications, it is more feasible to modify conditions at the neighborhood level than at the regional level. Yet for the promotion of bicycle transport we need to know whether relationships between micro-environmental factors and bicycle transport depend on different types of macro-environments. This study aimed to identify whether the effect of three micro-environmental factors (i.e., evenness of the cycle path surface, speed limits and type of separation between cycle path and motorized traffic) on the street's appeal for adults' bicycle transport varied across three different macro-environments (i.e., low, medium and high residential density street). In total, 389 middle-aged adults completed a web-based questionnaire consisting of socio-demographic characteristics and a series of choice tasks with manipulated photographs, depicting two possible routes to cycle along. Conjoint analysis was used to analyze the data. Although the magnitude of the overall effects differed, in each macro-environment (i.e., low, medium and high residential density), middle-aged adults preferred a speed limit of 30 km/h, an even cycle path surface and a hedge as separation between motorized traffic and the cycle path compared to a speed limit of 50 or 70 km/h, a slightly uneven or uneven cycle path surface and a curb as separation or no separation between motorized traffic and the cycle path. Our results suggest that irrespective of the macro-environment, the same micro-environmental factors are preferred in middle-aged adults concerning the street's appeal for bicycle transport. The controlled environment simulations in the experimental choice task have the potential to inform real life

  9. Does the Effect of Micro-Environmental Factors on a Street’s Appeal for Adults’ Bicycle Transport Vary across Different Macro-Environments? An Experimental Study

    Science.gov (United States)

    Mertens, Lieze; Van Cauwenberg, Jelle; Ghekiere, Ariane; Van Holle, Veerle; De Bourdeaudhuij, Ilse; Deforche, Benedicte; Nasar, Jack; Van de Weghe, Nico; Van Dyck, Delfien

    2015-01-01

    Background Characteristics of the physical environment can be classified into two broad categories: macro- (“raw” urban planning features influenced on a regional level) and micro- (features specifically within a streetscape influenced on a neighborhood level) environmental factors. In urban planning applications, it is more feasible to modify conditions at the neighborhood level than at the regional level. Yet for the promotion of bicycle transport we need to know whether relationships between micro-environmental factors and bicycle transport depend on different types of macro-environments. This study aimed to identify whether the effect of three micro-environmental factors (i.e., evenness of the cycle path surface, speed limits and type of separation between cycle path and motorized traffic) on the street’s appeal for adults’ bicycle transport varied across three different macro-environments (i.e., low, medium and high residential density street). Methods In total, 389 middle-aged adults completed a web-based questionnaire consisting of socio-demographic characteristics and a series of choice tasks with manipulated photographs, depicting two possible routes to cycle along. Conjoint analysis was used to analyze the data. Results Although the magnitude of the overall effects differed, in each macro-environment (i.e., low, medium and high residential density), middle-aged adults preferred a speed limit of 30 km/h, an even cycle path surface and a hedge as separation between motorized traffic and the cycle path compared to a speed limit of 50 or 70 km/h, a slightly uneven or uneven cycle path surface and a curb as separation or no separation between motorized traffic and the cycle path. Conclusions Our results suggest that irrespective of the macro-environment, the same micro-environmental factors are preferred in middle-aged adults concerning the street’s appeal for bicycle transport. The controlled environment simulations in the experimental choice task

  10. Does the Effect of Micro-Environmental Factors on a Street's Appeal for Adults' Bicycle Transport Vary across Different Macro-Environments? An Experimental Study.

    Directory of Open Access Journals (Sweden)

    Lieze Mertens

    Full Text Available Characteristics of the physical environment can be classified into two broad categories: macro- ("raw" urban planning features influenced on a regional level and micro- (features specifically within a streetscape influenced on a neighborhood level environmental factors. In urban planning applications, it is more feasible to modify conditions at the neighborhood level than at the regional level. Yet for the promotion of bicycle transport we need to know whether relationships between micro-environmental factors and bicycle transport depend on different types of macro-environments. This study aimed to identify whether the effect of three micro-environmental factors (i.e., evenness of the cycle path surface, speed limits and type of separation between cycle path and motorized traffic on the street's appeal for adults' bicycle transport varied across three different macro-environments (i.e., low, medium and high residential density street.In total, 389 middle-aged adults completed a web-based questionnaire consisting of socio-demographic characteristics and a series of choice tasks with manipulated photographs, depicting two possible routes to cycle along. Conjoint analysis was used to analyze the data.Although the magnitude of the overall effects differed, in each macro-environment (i.e., low, medium and high residential density, middle-aged adults preferred a speed limit of 30 km/h, an even cycle path surface and a hedge as separation between motorized traffic and the cycle path compared to a speed limit of 50 or 70 km/h, a slightly uneven or uneven cycle path surface and a curb as separation or no separation between motorized traffic and the cycle path.Our results suggest that irrespective of the macro-environment, the same micro-environmental factors are preferred in middle-aged adults concerning the street's appeal for bicycle transport. The controlled environment simulations in the experimental choice task have the potential to inform real life

  11. Quenching of excited uranyl ion during its photochemical reduction with triphenyl-phosphine : Part IV - effect of heterocyclic molecules

    International Nuclear Information System (INIS)

    Sidhu, M.S.; Bhatia, P.V.K.

    1994-01-01

    The presence of heterocyclic compounds triggers off a competition between photophysical and photochemical annihilation of excited uranyl ion during its photochemical reduction with triphenylphosphine. This competition is used to measure Stern-Volmer constant using UV visible spectrophotometer for quenching the uranyl ion luminescence with a number of heterocyclic molecules viz., pyridine, thiophene bipyridyl, tetrahydrofuran and piperidine. (author). 7 refs., 2 figs., 1 tab

  12. Synthesis and Regioselective Reaction of Some Unsymmetrical Heterocyclic Chalcone Derivatives and Spiro Heterocyclic Compounds as Antibacterial Agents.

    Science.gov (United States)

    El-Hashash, Maher A; Rizk, Sameh A; Atta-Allah, Saad R

    2015-12-10

    A number of novel heterocyclic chalcone derivatives can be synthesized by thermal and microwave tools. Treatment of 4-(4-Acetylamino- and/or 4-bromo-phenyl)-4-oxobut-2-enoic acids with hydrogen peroxide in alkaline medium were afforded oxirane derivatives 2. Reaction of the epoxide 2 with 2-amino-5-aryl-1,3,4-thiadiazole derivatives yielded chalcone of imidazo[2,1-b]thiadiazole derivative 4 via two thermal routes. In one pot reaction of 4-bromoacetophenone, diethyloxalate, and 2-amino-5-aryl-1,3,4-thiadiazole derivatives in MW irradiation (W 250 and T 150 °C) under eco-friendly conditions afforded an unsuitable yield of the desired chalcone 4d. The chalcone derivatives 4 were used as a key starting material to synthesize some new spiroheterocyclic compounds via Michael and aza-Michael adducts. The chalcone 4f was similar to the aryl-oxo-vinylamide derivatives for the inhibition of tyrosine kinase and cancer cell growth. The electron-withdrawing substituents, such as halogens, and 2-amino-1,3,4-thiadiazole moeity decreasing the electron density, thereby decreasing the energy of HOMO, and the presence of imidazothiadiazole moiety should improve the antibacterial activity. Thus, the newly synthesized compounds were evaluated for their anti-bacterial activity against (ATCC 25923), (ATCC 10987), (ATCC 274,) and (SM514). The structure of the newly synthesized compounds was confirmed by elemental analysis and spectroscopic data.

  13. Structural and spectral comparisons between isomeric benzisothiazole and benzothiazole based aromatic heterocyclic dyes

    Science.gov (United States)

    Wang, Yin-Ge; Wang, Yue-Hua; Tao, Tao; Qian, Hui-Fen; Huang, Wei

    2015-09-01

    A pair of isomeric heterocyclic compounds, namely 3-amino-5-nitro-[2,1]-benzisothiazole and 2-amino-6-nitrobenzothiazole, are used as the diazonium components to couple with two N-substituted 4-aminobenzene derivatives. As a result, two pairs of isomeric aromatic heterocyclic azo dyes have been produced and they are structurally and spectrally characterized and compared including single-crystal structures, electronic spectra, solvatochromism and reversible acid-base discoloration, thermal stability and theoretically calculations. It is concluded that both benzisothiazole and benzothiazole based dyes show planar molecular structures and offset π-π stacking interactions, solvatochromism and reversible acid-base discoloration. Furthermore, benzisothiazole based aromatic heterocyclic dyes exhibit higher thermal stability, larger solvatochromic effects and maximum absorption wavelengths than corresponding benzothiazole based ones, which can be explained successfully by the differences of their calculated isomerization energy, dipole moment and molecular band gaps.

  14. Enantioselective construction of quaternary N-heterocycles by palladium-catalysed decarboxylative allylic alkylation of lactams

    KAUST Repository

    Behenna, Douglas C.

    2011-12-18

    The enantioselective synthesis of nitrogen-containing heterocycles (N-heterocycles) represents a substantial chemical research effort and resonates across numerous disciplines, including the total synthesis of natural products and medicinal chemistry. In this Article, we describe the highly enantioselective palladium-catalysed decarboxylative allylic alkylation of readily available lactams to form 3,3-disubstituted pyrrolidinones, piperidinones, caprolactams and structurally related lactams. Given the prevalence of quaternary N-heterocycles in biologically active alkaloids and pharmaceutical agents, we envisage that our method will provide a synthetic entry into the de novo asymmetric synthesis of such structures. As an entry for these investigations we demonstrate how the described catalysis affords enantiopure quaternary lactams that intercept synthetic intermediates previously used in the synthesis of the Aspidosperma alkaloids quebrachamine and rhazinilam, but that were previously only available by chiral auxiliary approaches or as racemic mixtures. © 2012 Macmillan Publishers Limited. All rights reserved.

  15. Heterocyclic N-Oxides – An Emerging Class of Therapeutic Agents

    Science.gov (United States)

    Mfuh, Adelphe M.; Larionov, Oleg V.

    2016-01-01

    Heterocyclic N-oxides have emerged as potent compounds with anticancer, antibacterial, antihypertensive, antiparasitic, anti-HIV, anti-inflammatory, herbicidal, neuroprotective, and procognitive activities. The N-oxide motif has been successfully employed in a number of recent drug development projects. This review surveys the emergence of this scaffold in the mainstream medicinal chemistry with a focus on the discovery of the heterocyclic N-oxide drugs, N-oxide-specific mechanisms of action, drug-receptor interactions and synthetic avenues to these compounds. As the first review on this subject that covers the developments since 1950s to date, it is expected that it will inspire wider implementation of the heterocyclic N-oxide motif in the rational design of new medicinal agents. PMID:26087764

  16. Complexes of Th(IV) perchlorates, nitrates and thiocyanates with some heterocyclic bases

    International Nuclear Information System (INIS)

    Agarwal, R.K.; Srivastava, A.K.; Srivastava, M.; Bhakru, N.; Srivastava, T.N.

    1980-01-01

    Some Th(IV) perchlorate complexes of heterocyclic bases have been reported previously. Adducts of Th(IV) nitrates and thiocyanates with some heterocyclic N-oxides have been prepared and physico-chemical properties investigated. Comparatively little is known about the complexes of Th(IV) ion with the ligands containing nitrogen atom acting as electron donating centres. In view of this, the adducts of Th(IV) ion with certain nitrogen heterocyclic bases such as pyridine (Py), α-picoline (Pic), 2-amino pyridine (NH 2 Py), 2:4-lutidine (2,4LN), 2:6-lutidine, (2,6LN), quinoline (Q), isoquinoline (Isoq), 2,2'-bipyridine (Bipy) and 1,10-phenanthroline (Phen) were synthesised and characterised by analysis and IR absorption spectra. The results are presented and discussed. (author)

  17. North Central Texas Council of Governments peer exchange on bicycle and pedestrian count programs : a TPCB peer exchange

    Science.gov (United States)

    2013-05-29

    This report highlights key recommendations and best practices identified at the peer exchange on bicycle and pedestrian count programs, held on May 29 and May 30, 2013 in Arlington, Texas. The North Central Texas Council of Governments (NCTCOG) reque...

  18. Comprehensive database of Manufactured Gas Plant tars. Part C. Heterocyclic and hydroxylated polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Gallacher, Christopher; Thomas, Russell; Lord, Richard; Kalin, Robert M; Taylor, Chris

    2017-08-15

    Coal tars are a mixture of organic and inorganic compounds that were by-products from the manufactured gas and coke making industries. The tar compositions varied depending on many factors such as the temperature of production and the type of retort used. For this reason a comprehensive database of the compounds found in different tar types is of value to understand both how their compositions differ and what potential chemical hazards are present. This study focuses on the heterocyclic and hydroxylated compounds present in a database produced from 16 different tars from five different production processes. Samples of coal tar were extracted using accelerated solvent extraction (ASE) and derivatized post-extraction using N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) with 1% trimethylchlorosilane (TMCS). The derivatized samples were analysed using two-dimensional gas chromatography combined with time-of-flight mass spectrometry (GCxGC/TOFMS). A total of 865 heterocyclic compounds and 359 hydroxylated polycyclic aromatic hydrocarbons (PAHs) were detected in 16 tar samples produced by five different processes. The contents of both heterocyclic and hydroxylated PAHs varied greatly with the production process used, with the heterocyclic compounds giving information about the feedstock used. Of the 359 hydroxylated PAHs detected the majority would not have been be detected without the use of derivatization. Coal tars produced using different production processes and feedstocks yielded tars with significantly different heterocyclic and hydroxylated contents. The concentrations of the individual heterocyclic compounds varied greatly even within the different production processes and provided information about the feedstock used to produce the tars. The hydroxylated PAH content of the samples provided important analytical information that would otherwise not have been obtained without the use of derivatization and GCxGC/TOFMS. Copyright © 2017 John Wiley & Sons, Ltd.

  19. Lactoperoxidase, an Antimicrobial Milk Protein, as a Potential Activator of Carcinogenic Heterocyclic Amines in Breast Cancer.

    Science.gov (United States)

    Sheikh, Ishfaq Ahmad; Jiffri, Essam Hussain; Kamal, Mohammad Amjad; Ashraf, Ghulam Md; Beg, Mohd Amin

    2017-11-01

    Lactoperoxidase (LPO) is an antimicrobial protein secreted from mammary, salivary and other mucosal glands. It is an important member of heme peroxidase enzymes and the primary peroxidase enzyme present in breast tissues. In addition to the antimicrobial properties, LPO has been shown to be associated with breast cancer etiology. Heterocyclic amines, an important class of environmental and dietary carcinogens, have been increasingly associated with breast cancer etiology. Heterocyclic amines undergo activation in breast tissue as a result of oxidation by LPO. The current study includes three important heterocyclic amines, 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) and 2-amino-1-methy-6-phenylimidazo[4,5-b]-pyridine (PhIP), that have carcinogenic activity. The structural binding characterization of IQ, MeIQx and PhIP with LPO was done using in silico approaches. Their binding pattern and interactions with LPO amino acid residues were analyzed. The three compounds bound in the distal heme cavity of LPO without replacing the important water molecule required for oxidation of substrate compounds. PhIP displayed lesser binding affinity for LPO in comparison to IQ and MeIQx. The binding mode of heterocyclic amines in distal heme cavity of LPO resembled to that of substrate binding pattern. The three heterocyclic amines are suggested to act as LPO substrate. The undisturbed water molecule present in distal heme cavity of the LPO is expected to facilitate the oxidation and activation of the three heterocyclic amines. These activated compounds may potentially bind with DNA in breast tissues forming DNA adducts and may subsequently lead to breast cancer initiation. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  20. "Bicycles May Use Full Lane" Signage Communicates U.S. Roadway Rules and Increases Perception of Safety.

    Science.gov (United States)

    Hess, George; Peterson, M Nils

    2015-01-01

    Many global challenges, including obesity, health care costs, and climate change, could be addressed in part by increasing the use of bicycles for transportation. Concern about the safety of bicycling on roadways is frequently cited as a deterrent to increasing bicycle use in the USA. The use of effective signage along roadways might help alleviate these concerns by increasing knowledge about the rights and duties of bicyclists and motorists, ideally reducing crashes. We administered a web-based survey, using Twitter for recruitment, to examine how well three US traffic control devices communicated the message that bicyclists are permitted in the center of the travel lane and do not have to "get out of the way" to allow motorists to pass without changing lanes: "Bicycles May Use Full Lane" and "Share the Road" signage, and Shared Lane Markings on the pavement. Each was compared to an unsigned roadway. We also asked respondents whether it was safe for a bicyclist to occupy the center of the travel lane. "Bicycles May Use Full Lane" signage was the most consistently comprehended device for communicating the message that bicyclists may occupy the travel lane and also increased perceptions of safety. "Share the Road" signage did not increase comprehension or perceptions of safety. Shared Lane Markings fell somewhere between. "Bicycles May Use Full Lane" signage showed notable increases in comprehension among novice bicyclists and private motor vehicle commuters, critical target audiences for efforts to promote bicycling in the USA. Although limited in scope, our survey results are indicative and suggest that Departments of Transportation consider replacing "Share the Road" with "Bicycles May Use Full Lane" signage, possibly combined with Shared Lane Markings, if the intent is to increase awareness of roadway rights and responsibilities. Further evaluation through virtual reality simulations and on-road experiments is merited.

  1. Bicycles May Use Full Lane” Signage Communicates U.S. Roadway Rules and Increases Perception of Safety

    Science.gov (United States)

    2015-01-01

    Many global challenges, including obesity, health care costs, and climate change, could be addressed in part by increasing the use of bicycles for transportation. Concern about the safety of bicycling on roadways is frequently cited as a deterrent to increasing bicycle use in the USA. The use of effective signage along roadways might help alleviate these concerns by increasing knowledge about the rights and duties of bicyclists and motorists, ideally reducing crashes. We administered a web-based survey, using Twitter for recruitment, to examine how well three US traffic control devices communicated the message that bicyclists are permitted in the center of the travel lane and do not have to “get out of the way” to allow motorists to pass without changing lanes: “Bicycles May Use Full Lane” and “Share the Road” signage, and Shared Lane Markings on the pavement. Each was compared to an unsigned roadway. We also asked respondents whether it was safe for a bicyclist to occupy the center of the travel lane. “Bicycles May Use Full Lane” signage was the most consistently comprehended device for communicating the message that bicyclists may occupy the travel lane and also increased perceptions of safety. “Share the Road” signage did not increase comprehension or perceptions of safety. Shared Lane Markings fell somewhere between. “Bicycles May Use Full Lane” signage showed notable increases in comprehension among novice bicyclists and private motor vehicle commuters, critical target audiences for efforts to promote bicycling in the USA. Although limited in scope, our survey results are indicative and suggest that Departments of Transportation consider replacing “Share the Road” with “Bicycles May Use Full Lane” signage, possibly combined with Shared Lane Markings, if the intent is to increase awareness of roadway rights and responsibilities. Further evaluation through virtual reality simulations and on-road experiments is merited. PMID

  2. Bicycle physics and biomechanics. Techniques - formulas - laws. 9. rev. and enl. ed.; Fahrradphysik und Biomechanik. Technik - Formeln - Gesetze

    Energy Technology Data Exchange (ETDEWEB)

    Gressmann, M.

    2005-07-01

    Michael Gressmann explains the physical aspects of bicycle riding by numerous concrete examples: Acceleration and velocity, friction and rolling resistance, steering-gear angle and displacement, under- and override, bicycle gear/chain gear, muscle activity in the pedaling, energy and power balance. From this follow many interesting hints for the riding technique and the selection of the technical material. Especially valuable for the practitioner: Considerations and calculations on aerial resistance, gyro forces, frame geometry, seat position, and pedaling frequency.

  3. "Bicycles May Use Full Lane" Signage Communicates U.S. Roadway Rules and Increases Perception of Safety.

    Directory of Open Access Journals (Sweden)

    George Hess

    Full Text Available Many global challenges, including obesity, health care costs, and climate change, could be addressed in part by increasing the use of bicycles for transportation. Concern about the safety of bicycling on roadways is frequently cited as a deterrent to increasing bicycle use in the USA. The use of effective signage along roadways might help alleviate these concerns by increasing knowledge about the rights and duties of bicyclists and motorists, ideally reducing crashes. We administered a web-based survey, using Twitter for recruitment, to examine how well three US traffic control devices communicated the message that bicyclists are permitted in the center of the travel lane and do not have to "get out of the way" to allow motorists to pass without changing lanes: "Bicycles May Use Full Lane" and "Share the Road" signage, and Shared Lane Markings on the pavement. Each was compared to an unsigned roadway. We also asked respondents whether it was safe for a bicyclist to occupy the center of the travel lane. "Bicycles May Use Full Lane" signage was the most consistently comprehended device for communicating the message that bicyclists may occupy the travel lane and also increased perceptions of safety. "Share the Road" signage did not increase comprehension or perceptions of safety. Shared Lane Markings fell somewhere between. "Bicycles May Use Full Lane" signage showed notable increases in comprehension among novice bicyclists and private motor vehicle commuters, critical target audiences for efforts to promote bicycling in the USA. Although limited in scope, our survey results are indicative and suggest that Departments of Transportation consider replacing "Share the Road" with "Bicycles May Use Full Lane" signage, possibly combined with Shared Lane Markings, if the intent is to increase awareness of roadway rights and responsibilities. Further evaluation through virtual reality simulations and on-road experiments is merited.

  4. Can creatine supplementation form carcinogenic heterocyclic amines in humans?

    Science.gov (United States)

    Pereira, Renato Tavares dos Santos; Dörr, Felipe Augusto; Pinto, Ernani; Solis, Marina Yazigi; Artioli, Guilherme Giannini; Fernandes, Alan Lins; Murai, Igor Hisashi; Dantas, Wagner Silva; Seguro, Antônio Carlos; Santinho, Mirela Aparecida Rodrigues; Roschel, Hamilton; Carpentier, Alain; Poortmans, Jacques Remi; Gualano, Bruno

    2015-01-01

    Abstract Creatine supplementation has been associated with increased cancer risk. In fact, there is evidence indicating that creatine and/or creatinine are important precursors of carcinogenic heterocyclic amines (HCAs). The present study aimed to investigate the acute and chronic effects of low- and high-dose creatine supplementation on the production of HCAs in healthy humans (i.e. 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (8-MeIQx),  2-amino-(1,6-dimethylfuro[3,2-e]imidazo[4,5-b])pyridine (IFP) and 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx)). This was a non-counterbalanced single-blind crossover study divided into two phases, in which low- and high-dose creatine protocols were tested. After acute (1 day) and chronic supplementation (30 days), the HCAs PhIP, 8-MeIQx, IFP and 4,8-DiMeIQx were assessed through a newly developed HPLC–MS/MS method. Dietary HCA intake and blood and urinary creatinine were also evaluated. Out of 576 assessments performed (from 149 urine samples), only nine (3 from creatine and 6 from placebo) showed quantifiable levels of HCAs (8-MeIQx: n = 3; 4,8-DiMeIQx: n = 2; PhIP: n = 4). Individual analyses revealed that diet rather than creatine supplementation was the main responsible factor for HCA formation in these cases. This study provides compelling evidence that both low and high doses of creatine supplementation, given either acutely or chronically, did not cause increases in the carcinogenic HCAs PhIP, 8-MeIQx, IFP and 4,8-DiMeIQx in healthy subjects. These findings challenge the long-existing notion that creatine supplementation could potentially increase the risk of cancer by stimulating the formation of these mutagens. Key points There is a long-standing concern that creatine supplementation could be associated with cancer, possibly by facilitating the formation of carcinogenic heterocyclic amines (HCAs). This study provides compelling evidence

  5. Genetically modified CHO cells for studying the genotoxicity of heterocyclic amines from cooked foods

    International Nuclear Information System (INIS)

    Thompson, L.H.; Wu, R.W.; Felton, J.S.

    1995-07-01

    We have developed metabolically competent CHO cells to evaluate the genotoxicity associated with heterocyclic amines, such as those that are present in cooked foods. Into repair-deficient UV5 cells we introduced cDNAs for expressing cytochrome P450IA2 and acetyltransferases. We then genetically reverted these transformed lines to obtain matched metabolically competent repair-deficient/proficient lines. For a high mutagenic response, we find a requirement for acetyltransferase with IQ but not with PhIP. This system allows for both quantifying mutagenesis and analyzing the mutational spectra produced by heterocyclic amines

  6. Asymmetric Hydrogenation of Seven-Membered C=N-containing Heterocycles and Rationalization of the Enantioselectivity.

    Science.gov (United States)

    Balakrishna, Bugga; Bauzá, Antonio; Frontera, Antonio; Vidal-Ferran, Anton

    2016-07-18

    Iridium(I) complexes with phosphine-phosphite ligands efficiently catalyze the enantioselective hydrogenation of diverse seven-membered C=N-containing heterocyclic compounds (eleven examples; up to 97 % ee). The P-OP ligand L3, which incorporates an ortho-diphenyl substituted octahydrobinol phosphite fragment, provided the highest enantioselectivities in the hydrogenation of most of the heterocyclic compounds studied. The observed stereoselection was rationalized by means of DFT calculations. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. New synthesis of photocurable silanes and polysiloxanes bearing heterocyclic or olefinic functions

    International Nuclear Information System (INIS)

    Youssef, B.; Lecamp, L.; Garin, S.; Bunel, C.

    1999-01-01

    In this work, we described the synthesis of silanes and polysiloxanes bearing cationic photopolymerizable groups. Two new methods were used. The first one is the reaction between 3-mercapto-propyl-1-triethoxysilane (1) and chloromethylated olefins by a phase transfer catalysis. The second one is the radical addition of (1) or poly(dimethylsiloxane-co-methylmercaptopropylsiloxane) (9) to allyl or vinyl substituted heterocyclic monomers. These methods led to the expected adducts with an excellent yield. The polysiloxanes bearing heterocyclic functional groups linked through thioether bonds were photocurable by cationic route. Under UV light intensity of 17.5 mW/cm 2 , these polymers harden after 15 or 20 s

  8. Screening for heterocyclic amines in chicken cooked in various ways.

    Science.gov (United States)

    Solyakov, A; Skog, K

    2002-08-01

    Chicken cooked under well-controlled conditions and commercial chicken products were screened for heterocyclic amines (HAs). Chicken samples were boiled, deep-fried, pan-fried, oven-roasted, cooked in an unglazed clay pot or in a roasting bag in the oven, and oven broiled. 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 1-methyl-9H-pyrido[3,4-b]indole (harman) and 9H-pyrido[3,4-b]indole (norharman) were identified in several samples. Chicken cooked at low temperatures contained low amounts of HAs. In pan-fried chicken breasts, MeIQx was detected in amounts below 2 ng/g, 4,8-DiMeIQx below 0.6 ng/g, and PhIP in amounts up to 38 ng/g. Harman and norharman were detected in almost all samples (below 15 ng/g). In skin from a commercially barbecued chicken, MeIQx, 4,8-DiMeIQx and PhIP were detected, while only traces of MeIQx were detected in the meat. MeIQx was detected in a commercial chicken flavour, 0.1 ng/ml. No HAs were detected in pan-fried chicken liver. The results show that the content of HAs in chicken cooked in various ways is low if prepared at low temperatures, and increases with increasing cooking temperature. PhIP formation seems to start accelerating at cooking temperatures around or above 200 degrees C. Colour development increases with cooking temperature, but no correlation with HA content was observed.

  9. Predictors of dietary heterocyclic amine intake in three prospective cohorts.

    Science.gov (United States)

    Byrne, C; Sinha, R; Platz, E A; Giovannucci, E; Colditz, G A; Hunter, D J; Speizer, F E; Willett, W C

    1998-06-01

    Cooking meat creates heterocyclic amines (HCAs) through pyrolysis of amino acids and creatinine. Although recognized as mutagenic, the etiological role of HCA in human cancer is unclear, due to the lack of information on the effect of typical food cooking methods on HCA concentrations and on variation in HCA exposure in populations. We estimated overall daily dietary HCA intake and variation in intake between individuals, using recent data on HCA concentrations in various meats prepared by cooking methods, temperatures, and times common in United States in the 1990s. Random samples of 250 participants from each of three large prospective cohorts were mailed a questionnaire to assess frequency of consumption, cooking method, and typical outside appearance of pan-fried, broiled, and grilled or barbecued chicken, fish, hamburger, and steak; fried, microwaved, and broiled bacon; fried sausage; roast beef; and homemade gravy. The 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), and 2-amino-3,4,8-trimethylimidazo[4,5,f]quinoxaline (DiMeIQx) concentrations, measured in composite samples by solid-phase extraction and high-performance liquid chromatography, were assigned to each food, cooking method, and doneness level. The dietary reports showed approximately 30-fold relative variation in 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline intake, 20-fold for 2-amino- -methyl-6-phenylimidazo[4,5-b]pyridine, and over 110-fold for 2-amino-3,4,8-trimethylimidazo[4,5,f]quinoxaline, when the 10th and 90th percentiles of HCA intake were compared (90th/10th percentile value). These reported variations in HCA exposure among participants in these three large cohorts indicates that estimation of HCA intake and determination of association with disease risk are feasible, if additional information on meat cooking methods is obtained.

  10. Improving Energy Efficiency of an Autonomous Bicycle with Adaptive Controller Design

    Directory of Open Access Journals (Sweden)

    David Rodriguez-Rosa

    2017-05-01

    Full Text Available A method is proposed to achieve lateral stability of an autonomous bicycle with only the rotation of the front wheel. This can be achieved with a classic controller. However, if the energy consumption of the bicycle also has to be minimized, this solution is not valid. To solve this problem, an adaptive controller has been designed, which modifies its gains according to the bicycle’s forward velocity, adapting its response with minimum energy consumption and satisfying the design specifications. The study demonstrates the efficiency of the proposed control, achieving an energy saving of 73 . 8 % in trajectory tracking with respect to a conventional proportional-integral ( P I controller. These results show the importance of designing energy-efficient controllers, not only for autonomous vehicles but also for any automatic system where the energy consumption can be minimized.

  11. On the Effects of Tube Butting on the Structural Performance of Steel Bicycle Frames

    Directory of Open Access Journals (Sweden)

    Derek Covill

    2018-02-01

    Full Text Available Previous studies have shown how finite element analysis (FEA can be used to support designers and frame builders in the selection of butted tubes to tune the stiffness and strength behaviour of steel bicycles. The aim of this paper was therefore to analyse the effects of tube butting on the stiffness, stress distribution and energy absorption behaviour of bicycle frames using numerical simulations. Butted tubes were shown to provide a highly effective means to decrease mass whilst producing a disproportionately small change in stress compared with a straight gauge tubeset with a maximum material condition although there was no added benefit in terms of stiffness or strain energy. Conversely, decreasing the wall thickness produced an increase in stress at the tube ends that was disproportionate to the change in mass. This work can now be extended to analyse a fuller set of butted profiles for a range of tube types.

  12. Production of liquid fuels and chemicals from pyrolysis of Bangladeshi bicycle/rickshaw tire wastes

    Energy Technology Data Exchange (ETDEWEB)

    Islam, M. Rofiqul; Tushar, M.S.H.K. [Department of Mechanical Engineering, Rajshahi University of Engineering and Technology, Rajshahi 6204 (Bangladesh); Haniu, H. [Department of Mechanical Engineering, Kitami Institute of Technology, Kitami City, Hokkaido 090-8507 (Japan)

    2008-05-15

    Tire wastes in the form of used bicycle/rickshaw tires available in Bangladesh were pyrolyzed in a fixed-bed fire-tube heating reactor under different pyrolysis conditions to determine the role of final temperature, sweeping gas flow rate and feed size on the product yields and liquid product composition. Final temperature range studied was between 375 and 575 C and the highest liquid product yield was obtained at 475 C. Liquid products obtained under the most suitable conditions were characterized by elemental analyses, FT-IR, {sup 1}H NMR and GC-MS techniques. The results show that it is possible to obtain liquid products that are comparable to petroleum fuels and valuable chemical feedstock from bicycle/rickshaw tire wastes if the pyrolysis conditions are chosen accordingly. (author)

  13. Structure-activity relationship of antiparasitic and cytotoxic indoloquinoline alkaloids, and their tricyclic and bicyclic analogues.

    Science.gov (United States)

    Van Baelen, Gitte; Hostyn, Steven; Dhooghe, Liene; Tapolcsányi, Pál; Mátyus, Péter; Lemière, Guy; Dommisse, Roger; Kaiser, Marcel; Brun, Reto; Cos, Paul; Maes, Louis; Hajós, György; Riedl, Zsuzsanna; Nagy, Ildikó; Maes, Bert U W; Pieters, Luc

    2009-10-15

    Based on the indoloquinoline alkaloids cryptolepine (1), neocryptolepine (2), isocryptolepine (3) and isoneocryptolepine (4), used as lead compounds for new antimalarial agents, a series of tricyclic and bicyclic analogues, including carbolines, azaindoles, pyrroloquinolines and pyrroloisoquinolines was synthesized and biologically evaluated. None of the bicyclic compounds was significantly active against the chloroquine-resistant strain Plasmodium falciparum K1, in contrast to the tricyclic derivatives. The tricyclic compound 2-methyl-2H-pyrido[3,4-b]indole (9), or 2-methyl-beta-carboline, showed the best in vitro activity, with an IC(50) value of 0.45 microM against P. falciparum K1, without apparent cytotoxicity against L6 cells (SI>1000). However, this compound was not active in the Plasmodium berghei mouse model. Structure-activity relationships are discussed and compared with related naturally occurring compounds.

  14. A comparative study on the crystal structure of bicycle analogues to the natural phytotoxin helminthosporins

    Science.gov (United States)

    Barbosa, Luiz Cláudio de Almeida; Teixeira, Robson Ricardo; Nogueira, Leonardo Brandão; Maltha, Celia Regina Alvares; Doriguetto, Antônio Carlos; Martins, Felipe Terra

    2016-02-01

    Herein we described structural insights of a series of analogues to helminthosporin phytotoxins. The key reaction used to prepare the compounds corresponded to the [3 + 4] cycloaddition between the oxyallyl cation generated from 2,4-dibromopentan-3-one and different furans. Their structures were confirmed upon IR, NMR and X-ray diffraction analyses. While bicycles 7, 8 and 9 crystallize in the centrosymmetric monoclinic space group P21/c, compound 10 was solved in the noncentrosymmetric orthorhombic space group P212121. The solid materials obtained were shown to be racemic crystals (7, 8, 9) or racemic conglomerate (10). In all compounds, there is formation of a bicycle featured by fused tetrahydropyranone and 2,5-dihydrofuran rings. They adopt chair and envelope conformations, respectively. Crystal packing of all compounds is stabilized through C-H•••O contacts. Conformational aspects as well as similarities and differences among the crystal structures of the synthesized analogues are discussed.

  15. Understanding the preconditions for revitalizing bicycle transport in Beijing, with a reference study from Copenhagen

    DEFF Research Database (Denmark)

    Zhao, Chunli

    of transport and planning research by strengthening the knowledge base on the conditions that affect the use of bicycles in the megacities of developing world as well as by exploring the factors governing the populations’ attitudes towards their future mobility. Furthermore, the study contributes...... for accelerating the identification of effective solutions in specific cities and in specific planning cultures. For Beijing residents, the bicycle is currently a mode of transport for those with limited education and limited financial resources. The young Beijingers are least likely to cycle. This age difference...... is likely to be partly due to a cohort difference and, thus, indicates a growing problem for cycling in Beijing. On the other hand, clear associations with density and other urban form variables indicate that the proximity environment and urban development policies can also affect cycling. The effect...

  16. The effect of cannabis on regular cannabis consumers' ability to ride a bicycle.

    Science.gov (United States)

    Hartung, Benno; Schwender, Holger; Roth, Eckhard H; Hellen, Florence; Mindiashvili, Nona; Rickert, Annette; Ritz-Timme, Stefanie; Grieser, Almut; Monticelli, Fabio; Daldrup, Thomas

    2016-05-01

    To assess the effects of cannabis on the ability required to ride a bicycle, repetitive practical cycling tests and medical examinations were carried out before and after inhalative consumption of cannabis. A maximum of three joints with body weight-adapted THC content (300 μg THC per kg body weight) could be consumed by each test subject. Fourteen regular cannabis-consuming test subjects were studied (12 males, 2 females). In summary, only a few driving faults were observed even under the influence of very high THC concentrations. A defined THC concentration that leads to an inability to ride a bicycle cannot be presented. The test subjects showed only slight distinctive features that can be documented using a medical test routinely run for persons under suspicion of driving under the influence of alcohol or drugs.

  17. Particulates and noise exposure during bicycle, bus and car commuting: A study in three European cities.

    Science.gov (United States)

    Okokon, Enembe O; Yli-Tuomi, Tarja; Turunen, Anu W; Taimisto, Pekka; Pennanen, Arto; Vouitsis, Ilias; Samaras, Zissis; Voogt, Marita; Keuken, Menno; Lanki, Timo

    2017-04-01

    In order to curb traffic-related air pollution and its impact on the physical environment, contemporary city commuters are encouraged to shift from private car use to active or public transport modes. However, personal exposures to particulate matter (PM), black carbon and noise during commuting may be substantial. Therefore, studies comparing exposures during recommended modes of transport versus car trips are needed. We measured personal exposure to various-sized particulates, soot, and noise during commuting by bicycle, bus and car in three European cities: Helsinki in Finland, Rotterdam in the Netherlands and Thessaloniki in Greece using portable monitoring devices. We monitored commonly travelled routes in these cities. The total number of one-way trips yielding data on any of the measured parameters were 84, 72, 94 and 69 for bicycle, bus, closed-window car and open-window car modes, respectively. The highest mean PM 2.5 (85µg/m 3 ), PM 10 (131µg/m 3 ), black carbon (10.9µg/m 3 ) and noise (75dBA) levels were recorded on the bus, bus (again), open-window car and bicycle modes, respectively, all in Thessaloniki, PM and soot concentrations were generally higher during biking and taking a bus than during a drive in a a car with closed windows. Ratios of bike:car PM 10 ranged from 1.1 in Thessaloniki to 2.6 in Helsinki, while bus:car ratios ranged from in 1.0 in Rotterdam to 5.6 in Thessaloniki. Higher noise levels were mostly recorded during bicycle rides. Based on our study, active- and public-transport commuters are often at risk of higher air pollution and noise exposure than private car users. This should be taken into account in urban transportation planning. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Association between neighborhood walkability and GPS-measured walking, bicycling and vehicle time in adolescents.

    Science.gov (United States)

    Carlson, Jordan A; Saelens, Brian E; Kerr, Jacqueline; Schipperijn, Jasper; Conway, Terry L; Frank, Lawrence D; Chapman, Jim E; Glanz, Karen; Cain, Kelli L; Sallis, James F

    2015-03-01

    To investigate relations of walking, bicycling and vehicle time to neighborhood walkability and total physical activity in youth. Participants (N=690) were from 380 census block groups of high/low walkability and income in two US regions. Home neighborhood residential density, intersection density, retail density, entertainment density and walkability were derived using GIS. Minutes/day of walking, bicycling and vehicle time were derived from processing algorithms applied to GPS. Accelerometers estimated total daily moderate-to-vigorous physical activity (MVPA). Models were adjusted for nesting of days (N=2987) within participants within block groups. Walking occurred on 33%, active travel on 43%, and vehicle time on 91% of the days observed. Intersection density and neighborhood walkability were positively related to walking and bicycling and negatively related to vehicle time. Residential density was positively related to walking. Increasing walking in youth could be effective in increasing total physical activity. Built environment findings suggest potential for increasing walking in youth through improving neighborhood walkability. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Real-time bicycle detection at signalized intersections using thermal imaging technology

    Science.gov (United States)

    Collaert, Robin

    2013-02-01

    More and more governments and authorities around the world are promoting the use of bicycles in cities, as this is healthy for the bicyclist and improves the quality of life in general. Safety and efficiency of bicyclists has become a major focus. To achieve this, there is a need for a smarter approach towards the control of signalized intersections. Various traditional detection technologies, such as video, microwave radar and electromagnetic loops, can be used to detect vehicles at signalized intersections, but none of these can consistently separate bikes from other traffic, day and night and in various weather conditions. As bikes should get a higher priority and also require longer green time to safely cross the signalized intersection, traffic managers are looking for alternative detection systems that can make the distinction between bicycles and other vehicles near the stop bar. In this paper, the drawbacks of a video-based approach are presented, next to the benefits of a thermal-video-based approach for vehicle presence detection with separation of bicycles. Also, the specific technical challenges are highlighted in developing a system that combines thermal image capturing, image processing and output triggering to the traffic light controller in near real-time and in a single housing.

  20. Pedaling into high gear for bicycle policy in Canada : lessons from bike summit 2008 in Toronto

    International Nuclear Information System (INIS)

    2008-01-01

    The 2008 bike summit provided a forum for the discussion of international and Canadian best practices related to bicycles and bicycling policy. The aim of the summit was to assist communities across Canada to improve conditions for cycling in the urban environment and help to generate a cultural shift towards greater acceptance of cycling on roads. This paper discussed lessons learned during the summit and outlined new methods of improving cycling in communities. The City of London has recently increased the amount of cyclists using its roads by 200 per cent. Cycling infrastructure is more affordable than constructing major public transit or road infrastructure. Savings in healthcare costs will be accrued over time as a result of the healthier lifestyles promoted by regular cycling activity. Bicycle trips can help to alleviate over-demand on heavy transit routes. Encouraging commuters to cycle will also reduce the amounts of greenhouse gases (GHGs) emitted in urban areas. Lane width reductions will help to reduce speeds as drivers are forced to pay more attention when driving. Public bike sharing programs and bike stations are now being used in many North American cities. It was concluded that strong advocacy is needed to ensure the growth and acceptance of cycling in urban centres. 23 figs

  1. Peptides derivatized with bicyclic quaternary ammonium ionization tags. Sequencing via tandem mass spectrometry.

    Science.gov (United States)

    Setner, Bartosz; Rudowska, Magdalena; Klem, Ewelina; Cebrat, Marek; Szewczuk, Zbigniew

    2014-10-01

    Improving the sensitivity of detection and fragmentation of peptides to provide reliable sequencing of peptides is an important goal of mass spectrometric analysis. Peptides derivatized by bicyclic quaternary ammonium ionization tags: 1-azabicyclo[2.2.2]octane (ABCO) or 1,4-diazabicyclo[2.2.2]octane (DABCO), are characterized by an increased detection sensitivity in electrospray ionization mass spectrometry (ESI-MS) and longer retention times on the reverse-phase (RP) chromatography columns. The improvement of the detection limit was observed even for peptides dissolved in 10 mM NaCl. Collision-induced dissociation tandem mass spectrometry of quaternary ammonium salts derivatives of peptides showed dominant a- and b-type ions, allowing facile sequencing of peptides. The bicyclic ionization tags are stable in collision-induced dissociation experiments, and the resulted fragmentation pattern is not significantly influenced by either acidic or basic amino acid residues in the peptide sequence. Obtained results indicate the general usefulness of the bicyclic quaternary ammonium ionization tags for ESI-MS/MS sequencing of peptides. Copyright © 2014 John Wiley & Sons, Ltd.

  2. A Study for Adjustable Riding Position of the Innovation Bicycle Design

    Science.gov (United States)

    Huang, Yu-Che; Huang, Tai-Shen

    2018-04-01

    This research is about the analysis and design of the user in a wheelchair use posture can be changed. So user can through different sitting posture changes to provide different needs, so the folding design patents for the existing data collection and classification, through the analysis of advantages and disadvantages, further to find the innovative design approach. Finally through the multi linkage mechanism system, change the seat, handlebars and rear position, provide different posture context. In order to reduce the cost, this study is designed to integrate the innovation input mechanism, multi linkage system, through the construction of 10 joints and degrees of freedom of the bicycle frame. Then use 3D software to design of bicycle the size of the frame of innovation, through the three-dimensional CAD model to simulate the mechanism between movement and interference, and to evaluate the 3D The virtual prototype can meet the requirement. It will also enable CAE to analyze and determine the strength and the safety of the bicycle frame structure of ANSYS11.0 stress. Finally, we have integrated design through CAID to make a product appearance, the focus of research is mainly a study of CAD, CAE, CAID integration the production and the completion of a prototype.

  3. Usage Patterns of Electric Bicycles: An Analysis of the WeBike Project

    Directory of Open Access Journals (Sweden)

    Christian Gorenflo

    2017-01-01

    Full Text Available This paper presents an analysis of data collected through the Waterloo WeBike project: a field trial in which over 30 sensor-equipped electric bicycles (e-bikes were given to members of the University of Waterloo for personal use. Our dataset includes e-bike trips and battery charging sessions spanning nearly three years, from summer 2014 until spring 2017. We also conducted three surveys both before and during the trial. Our main findings were that the primary purpose of the e-bikes in our trial was for commuting, with most trips lasting less than 20 minutes and most trips taking place in the summer months. Our battery charging analysis revealed no evidence of range anxiety, and our analysis of survey results showed little correlation between anticipated and actual use. Furthermore, when asked about their opinions about various modes of transportation, our participants rated regular bicycles higher than e-bikes even after becoming familiar with e-bikes through the field trial. Based on our analysis, we draw several conclusions, including the fact that the general population in Canada is still unaware of e-bikes and their potential. Moreover, e-bike manufacturers should target sales to nonbike users, such as seniors, rather than trying to displace sales of regular bicycles.

  4. Synthesis and Characterization of Ag(I) and Pd(II) Complexes with a Pyridine Substituted N-Heterocyclic Carbene Ligand

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ga Young; Jung, Hyun Jin; Lee, Dong Heon [Chonbuk National Univ., Jeonju (Korea, Republic of); Park, Gyung Se [Kunsan National Univ., Kunsan (Korea, Republic of)

    2010-06-15

    We have used our new tridentate pyridine substituted N-heterocyclic carbene to generate an interesting trinuclear [((MepyCH{sub 2}){sub 2}-Im){sub 3}Ag{sub 3}]{sup 3+} complex, displaying very short Ag-Ag separations. A Pd(II)-NHC complex was prepared from [((MepyCH{sub 2}){sub 2}-Im){sub 3}Ag{sub 3}]{sup 3+} via a facile transmetallation, leading to a dimeric [(MepyCH{sub 2}){sub 2}-ImPdCl]{sub 2}{sup 2+} complex. Future plans are underway for the survey of the potential applications of these new NHC complexes as luminesent materials or homogeneous catalysts. Since Arduengo's discovery of the first isolable free carbene in 1991, N-heterocyclic carbenes (NHC) have been extensively utilized as ligands for transition metals. NHC are generally more stable than two extreme types of carbenes, the Fischer and the Schrock carbenes. They are good σ donors like most tertiary phosphins, PR{sub 3}, but the π-bonding with the metal is rather weak. The thriving studies of NHC-coordinated metal complexes produced a wide range of applications from homogeneous catalysts to materials science.

  5. Synthesis, electrochemical, structural and theoretical study of new derivatives of OABAN and OABAO heterocycles

    Czech Academy of Sciences Publication Activity Database

    Mikysek, T.; Kvapilová, Hana; Doušová, H.; Josefík, F.; Šimůnek, P.; Růžičková, Z.; Ludvík, Jiří

    2017-01-01

    Roč. 455, č. 2 (2017), s. 465-472 ISSN 0020-1693 R&D Projects: GA MŠk LD14129 Institutional support: RVO:61388955 Keywords : boron heterocycles * synthesis * electrochemistry Subject RIV: CG - Electrochemistry OBOR OECD: Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis) Impact factor: 2.002, year: 2016

  6. N,N'-diamidoketenimines via coupling of isocyanides to an N-heterocyclic carbene.

    Science.gov (United States)

    Hudnall, Todd W; Moorhead, Eric J; Gusev, Dmitry G; Bielawski, Christopher W

    2010-04-16

    Treatment of an N-heterocyclic carbene that features two amide groups N-bound to the carbene nucleus with various organic isocyanides afforded a new class of ketenimines in yields of up to 96% (isolated). DFT analyses revealed that the carbene exhibits a unique, low-lying LUMO, which may explain the atypical reactivity observed.

  7. N-heterocyclic carbene copper(I) catalysed N-methylation of amines using CO2

    KAUST Repository

    Santoro, Orlando

    2015-09-30

    The N-methylation of amines using CO2 and PhSiH3 as source of CH3 was efficiently performed using a N-heterocyclic carbene copper(I) complex. The methodology was found compatible with aromatic and aliphatic primary and secondary amines. Synthetic and computational studies have been carried out to support the proposed reaction mechanism for this transformation.

  8. Identification of the Eight-Membered Heterocycles Hicksoanes A-C from the Gorgonian Subergorgia hicksoni

    Czech Academy of Sciences Publication Activity Database

    Řezanka, Tomáš; Hanuš, L. O.; Dembitsky, V. M.; Sigler, Karel

    2008-01-01

    Roč. 2008, č. 7 (2008), s. 1265-1270 ISSN 1434-193X R&D Projects: GA MŠk 1P05OC073 Institutional research plan: CEZ:AV0Z50200510 Keywords : gorgonians * nitrogen heterocycles * natural products Subject RIV: EE - Microbiology, Virology Impact factor: 3.016, year: 2008

  9. MICROWAVE IRRADIATION IN BENIGN SYNTHESIS OF HETEROCYCLES, NOBLE NANOMETALS AND NANOCOMPOSITES

    Science.gov (United States)

    A brief historic account of reactions involving microwave (MW) exposure of neat reactants or catalyzed by mineral support surfaces, such as alumina, silica, clay, or their ‘doped’ versions, for the rapid one-pot assembly of heterocyclic compounds [1] from in situ generated reacti...

  10. Study of physicochemical properties of zinc(II) butyrate complex compounds with some heterocyclic ligands

    Czech Academy of Sciences Publication Activity Database

    Szakácsová, M.; Györová, K.; Szunyogová, E.; Kovářová, Jana

    2002-01-01

    Roč. 96, - (2002), s. 383 ISSN 0009-2770. [Meeting of Chemical Societies /54./. 30.06.2002-04.07.2002, Brno] R&D Projects: GA AV ČR KSK4050111; GA MŠk VEGA 1/9247/02; GA MŠk VEGA 047/074 Keywords : butyrate complex compounds * heterocyclic ligands Subject RIV: CD - Macromolecular Chemistry

  11. Mixed-ligand complexes of zirconium (IV) and uranium with salicylaldehyde and some heterocyclic azopyrazolones

    International Nuclear Information System (INIS)

    Amrallahi, A.H.

    1994-01-01

    Mixed-ligand complexes of Zr(IV) and U(IV) with salicylaldehyde (SA) and some heterocyclic azopyrazolenes have been studied spectrophotometrically. All formed chelates have ratio 1:1:1. The stoichiometry and stability of the binary mixed chelates been evaluated. Elemental analysis, molar conductance and IR spectra have been used for identification of solid mixed complexes. (author)

  12. Bent Shaped 1,3,4-Oxadiazole/Thiadiazole heterocyclic rings ...

    Indian Academy of Sciences (India)

    Two series of bent shaped 1,3,4-oxadiazole/thiadiazole heterocyclic ring containing liquid crystalline (LC) compounds were synthesized and characterized by FT-IR, 1H, 13C-NMR and ESI-Mass spectro-scopic techniques. Liquid crystal properties were investigated by polarized optical microscopy and differential scanning ...

  13. Design, synthesis and antibreast cancer MCF-7 cells biological evaluation of heterocyclic analogs of resveratrol.

    Science.gov (United States)

    Du, Cheng; Dong, Ming-Hui; Ren, Yu-Jie; Jin, Lu; Xu, Cheng

    2017-09-01

    A new series of resveratrol heterocyclic analogs (4a-m) were designed and synthesized, and their inhibitiory effects on MCF-7 cells were evaluated to investigate structure-activity relationship. The effects of these analogs on human breast cancer MCF-7 cells were also determined. Results showed that MCF-7 cells could be inhibited more potently by these analogs than by resveratrol (IC 50  = 80.0 μM). Among the analogs, compounds 4c, 4e, and 4k showed a significantly higher activity (IC 50  = 42.7, 48.1, and 43.4 μM) than resveratrol. Furthermore, the derivatives without additional heterocyclic structure in the 4'-OH position exhibited a more potent activity than that with addition heterocyclic structure. In addition, docking simulation was performed to adequately position compound 4c in a human F 1 -ATPase active site to determine a probable binding model. These heterocyclic analogs could be effective candidates for the chemoprevention of human breast cancer.

  14. Synthesis of acetylene alcohols of heterocyclic type and the acyl derivatives

    Directory of Open Access Journals (Sweden)

    Moldir Dyusebaeva

    2015-03-01

    Full Text Available A synthesis of potentially biologically active heterocyclic amino alcohols of acetylene (Piperidine and Morpholine under the conditions of Mannich reaction accomplished and received their acyl derivatives. Pharmacological activity (antibacterial and antispasmotic of synthesized compounds, also acute toxicological characteristics studied. The study showed that the combination of DMAE-4 has antispasmodic activity with low toxicity.

  15. Enaminone in heterocyclic synthesis: synthesis of new pyrazolopyrazole, pyrazolothienooxazine and pyrazolothienopyridine derivatives

    International Nuclear Information System (INIS)

    Hafiz, I.S.; Rahim, M.A.M.A.

    2014-01-01

    The chemical reactivity of enaminone 2 toward some nucleophilic and electrophilic reagents was investigated. Enaminone 2 was used as a key precursor for the synthesis of many important heterocyclic compounds. The synthesized compounds were characterized by IR, 1H-NMR, MS spectral and elemental analysis. (author)

  16. Complexes of uranyl with N-oxides of heterocyclic amines. Electron-vibrational absorption spectra

    International Nuclear Information System (INIS)

    Jezowska-Trzebiatowska, B.; Wieczorek, M.

    1977-01-01

    A number of coordination compounds formed by uranyl chloride and nitrate with N-oxides of heterocyclic amines have been prepared and characterized by spectral measurements in the absorption region 20000-50000 cm -1 . The electrons and vibronic transitions have been determined and discussed. (author)

  17. Correlations between electrochemical and spectrochemical parameters of ruthenium sulfoxides series with N-heterocyclic

    International Nuclear Information System (INIS)

    Oliveira, D. de; Toma, H.E.

    1990-01-01

    A systematic study of Ru Cl sub(2) (DMSO) sub(2) L sub(2) derivates, where L = N-heterocyclic base is described, contributing for a best understanding of chemical behaviour and electronic structure of the ruthenium sulfoxides. The correlations between the electrochemical and the spectroscopical parameters of the serie are presented with more emphasis. (author)

  18. Enantioselective [3+3] atroposelective annulation catalyzed by N-heterocyclic carbenes

    KAUST Repository

    Zhao, Changgui; Guo, Donghui; Munkerup, Kristin; Huang, Kuo-Wei; Li, Fangyi; Wang, Jian

    2018-01-01

    on the transition-metal-catalyzed transformations. Here, we report the enantioselective NHC-catalyzed (NHC: N-heterocyclic carbenes) atroposelective annulation of cyclic 1,3-diones with ynals. In the presence of NHC precatalyst, base, Lewis acid and oxidant, a

  19. N-Heterocyclic carbene functionalized goup 7-9 transition metal

    NARCIS (Netherlands)

    Aktas, H.; Slootweg, J.C.; Ehlers, A.W.; Lutz, M.; Spek, A.L.; Lammertsma, K.

    2009-01-01

    The N-heterocyclic carbene (NHC) functionalized phosphinidene complexes [(pCy)(IiPr2Me2)- RudPMes*] (4), [(pCy)(IiPr2Me2)OsdPMes*] (6), and [(Cp*)(IiPr2Me2)RhdPMes*] (7) were generated by a double-dehydrohalogenation-ligation sequence of the corresponding primary phosphine complexes with 3 equiv of

  20. Mechanistic Investigation of the Ruthenium–N-Heterocyclic-Carbene-Catalyzed Amidation of Alcohols and Amines

    DEFF Research Database (Denmark)

    Makarov, Ilya; Fristrup, Peter; Madsen, Robert

    2012-01-01

    The mechanism of the ruthenium–N-heterocyclic-carbene-catalyzed formation of amides from alcohols and amines was investigated by experimental techniques (Hammett studies, kinetic isotope effects) and by a computational study by using dispersion-corrected density functional theory (DFT/ M06...

  1. Expedient Access to an N -phenylpyrrolidin-2-yl Heterocycle via a ...

    African Journals Online (AJOL)

    Expedient Access to an N -phenylpyrrolidin-2-yl Heterocycle via a Base-Induced Intramolecular aza -Michael Reaction. ... in good overall yield when employing a stoichiometric amount of base to facilitate the intramolecular aza-Michael reaction. Keywords: aza Michael, intramolecular, catalysed, piperidine, pyrrolidine, base ...

  2. N-heterocyclic carbene copper(I) catalysed N-methylation of amines using CO2

    KAUST Repository

    Santoro, Orlando; Lazreg, Faï ma; Minenkov, Yury; Cavallo, Luigi; Cazin, Catherine S. J.

    2015-01-01

    The N-methylation of amines using CO2 and PhSiH3 as source of CH3 was efficiently performed using a N-heterocyclic carbene copper(I) complex. The methodology was found compatible with aromatic and aliphatic primary and secondary amines. Synthetic and computational studies have been carried out to support the proposed reaction mechanism for this transformation.

  3. Bis-ligated Ti and Zr complexes of chelating N-heterocyclic carbenes

    KAUST Repository

    El-Batta, Amer; Waltman, Andrew W.; Grubbs, Robert H.

    2011-01-01

    In this communication we report the synthesis of novel titanium and zirconium complexes ligated by bidentate "salicylaldimine-like" N-heterocyclic carbenes (NHC). Double addition of the NHC chelate to either TiCl4(thf)2 or ZrCl4 forms bis

  4. Dietary exposure to heterocyclic amines in a Chinese population.

    Science.gov (United States)

    Wong, Kin-Yoke; Su, Jin; Knize, Mark G; Koh, Woon-Puay; Seow, Adeline

    2005-01-01

    Heterocyclic aromatic amines (HAAs) formed in meat during high-temperature cooking have been associated with risk of colorectal and breast cancer. Incidence of these cancers is increasing in Singapore, a country with 77% ethnic Chinese. The purpose of this study was to estimate HAA levels in the Chinese diet and individual levels of exposure to these compounds because little is known. Twenty-five samples (each pooled from three sources) of meat and fish, cooked as commonly consumed, were analyzed by high-performance liquid chromatography for concentrations (ng/g) of 2-amino-3-methylimidazo[4,5-f]quinoline, 2-amino-3, 4-dimethylimidazo[4,5-f]quinoline (MeIQ), 2-amino-3,8- dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3, 4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx), 2- amino-3,7,8-trimethylimidazo[4,5-f]quinoxaline, 2-amino -1,6-dimethylfuro[3,2-e]imidazo[4,5-b]pyridine, and 2- amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Dietary meat consumption data (g/day), including meat type and cooking method, were gathered from food-frequency questionnaires completed by 497 randomly sampled Chinese men and women aged 20-59 yr. PhIP, MeIQx, and 4,8-DiMeIQx were the most abundant HAAs detected. Total HAA concentrations ranged from roasted pork had the highest levels. The estimated mean daily exposure to HAA was 49.95 ng/day (P10 14.0 ng/day, P90 95.8 ng/day); this was 50% higher among younger (20-39 yr) compared with older individuals. Seven specific meat-cooking method combinations contributed 90.1% of this intake, namely, pan-fried fish, pork, and chicken, deep-fried chicken as well as fish, roasted/barbecued pork, and grilled minced beef.

  5. Photolysis of Heterocyclic Lactones in Cryogenic Inert Matrices

    International Nuclear Information System (INIS)

    Kus, N.

    2008-01-01

    Heterocyclic lactones receive important uses in organic synthesis and are important biologically active compounds. Their weak toxicity and easy synthesis have made these compounds the subject of great interest and extensive investigation. Since long ago, lactones have been shown to possess an interesting photochemistry. Some representative six- and five-membered conjugated lactones [α-pyrone and some of its derivatives, including coumarin and 3-acetamido coumarin, 2(5H)-furanone] were recently investigated by infrared spectroscopy using the matrix isolation technique and quantum chemical calculations in our laboratories. Two main competitive photochemical reaction pathways could be identified: (i) ring-opening, leading to formation of the isomeric aldehyde-ketene, and (ii) ring-contraction leading to the corresponding Dewar isomers. For α-pyrone and 2(5H)-furanone, the ring-opening process dominates over the ring-contraction reaction, the same occurring for derivatives of these compounds bearing a voluminous substituent at position 3. In 2(5H)-furanone, the ring-opening reaction requires the simultaneous occurrence of a [1,2]-hydrogen atom migration, which was found to occur upon excitation at λ> 235 nm. Under the identical UV-irradiation (λ> 235 nm) of the six-membered analogues, the ring-opening reaction was more efficient in α-pyrone than in coumarin, and factors explaining this observation will be discussed. In turn, the Dewar forms of the studied compounds, resulting from the ring-contraction photoreaction, were found to undergo subsequent photo-elimination of CO 2 , with formation of the corresponding cycloalkenes. In the matrices, CO 2 and the simultaneously formed cycloalkenes were predicted by calculations to exist as associates, in which the CO 2 molecule is preferentially placed over the cycloalkene ring in a stacked-type geometry. For coumarin, a third photoreaction channel was observed, leading to formation of benzofurane and CO. This additional

  6. U.S. dietary exposures to heterocyclic amines.

    Science.gov (United States)

    Bogen, K T; Keating, G A

    2001-01-01

    Heterocyclic amines (HAs) formed in fried, broiled or grilled meats are potent mutagens that increase rates of colon, mammary, prostate and other cancers in bioassay rodents. Studies of how human dietary HA exposures may affect cancer risks have so far relied on fairly crudely defined HA-exposure categories. Recently, an integrated, quantitative approach to HA-exposure assessment (HAEA) was developed to estimate compound-specific intakes for particular individuals based on corresponding HA-concentration estimates that reflect their meat-type, intake-rate, cooking-method and meat-doneness preferences. This method was applied in the present study to U.S. national Continuing Survey of Food Intakes by Individuals (CSFII) data on meats consumed and cooking methods used by >25,000 people, after adjusting for underreported energy intake and conditional on meat-doneness preferences estimated from additional survey data. The U.S. population average lifetime time-weighted average of total HAs consumed was estimated to be approximately 9 ng/kg/day, with 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) estimated to comprise about two thirds of this intake. Pan-fried meats were the largest source of HA in the diet and chicken the largest source of HAs among different meat types. Estimated total HA intakes by male vs. female children were generally similar, with those by (0- to 15-year-old) children approximately 25% greater than those by (16+-year-old) adults. Race-, age- and sex-specific mean HA intakes were estimated to be greatest for African American males, who were estimated to consume approximately 2- and approximately 3-fold more PhIP than white males at ages <16 and 30+ years, respectively, after considering a relatively greater preference for more well-done items among African Americans based on national survey data. This difference in PhIP intakes may at least partly explain why prostate cancer (PC) kills approximately 2-fold more African American than white men

  7. New Palladium-Catalyzed Approaches to Heterocycles and Carbocycles

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Qinhua [Iowa State Univ., Ames, IA (United States)

    2004-12-19

    The tert-butylimines of o-(1-alkynyl)benzaldehydes and analogous pyridinecarbaldehydes have been cyclized under very mild reaction conditions in the presence of I2, ICl, PhSeCl, PhSCl and p-O2NC6H4SCl to give the corresponding halogen-, selenium- and sulfur-containing disubstituted isoquinolines and naphthyridines, respectively. Monosubstituted isoquinolines and naphthyridines have been synthesized by the metal-catalyzed ring closure of these same iminoalkynes. This methodology accommodates a variety of iminoalkynes and affords the anticipated heterocycles in moderate to excellent yields. The Pd(II)-catalyzed cyclization of 2-(1-alkynyl)arylaldimines in the presence of various alkenes provides an efficient way to synthesize a variety of 4-(1-alkenyl)-3-arylisoquinolines in moderate to excellent yields. The introduction of an ortho-methoxy group on the arylaldimine promotes the Pd-catalyzed cyclization and stabilizes the resulting Pd(II) intermediate, improving the yields of the isoquinoline products. Highly substituted naphthalenes have been synthesized by the palladium-catalyzed annulation of a variety of internal alkynes, in which two new carbon-carbon bonds are formed in a single step under relatively mild reaction conditions. This method has also been used to synthesize carbazoles, although a higher reaction temperature is necessary. The process involves arylpalladation of the alkyne, followed by intramolecular Heck olefination and double bond isomerization. This method accommodates a variety of functional groups and affords the anticipated highly substituted naphthalenes and carbazoles in good to excellent yields. Novel palladium migratiodarylation methodology for the synthesis of complex fused polycycles has been developed, in which one or more sequential Pd-catalyzed intramolecular migration processes involving C-H activation are employed. The chemistry works best with electron-rich aromatics, which is in agreement

  8. Dynamic fuzzy cognitive network approach for modelling and control of PEM fuel cell for power electric bicycle system

    International Nuclear Information System (INIS)

    Kheirandish, Azadeh; Motlagh, Farid; Shafiabady, Niusha; Dahari, Mahidzal; Khairi Abdul Wahab, Ahmad

    2017-01-01

    Highlights: •Fuzzy cognitive map was proposed for the first time to describe the behaviour of fuel cell electric bicycle system. •Fuzzy rules were applied to explain the cause and effect between concepts. •To predict and analyse the cognitive map involved in the negotiation process. -- Abstract: Modelling Proton Exchange Membrane Fuel Cell (PEMFC) is the fundamental step in designing efficient systems for achieving higher performance. Among the development of new energy technologies, modelling and optimization of energy processes with pollution reduction, sufficient efficiency and low emission are considered one of the most promising areas of study. Despite affecting factors in PEMFC functionality, providing a reliable model for PEMFC is the key of performance optimization challenge. In this paper, fuzzy cognitive map has been used for modelling PEMFC system that is directed to provide a dynamic cognitive map from the affecting factors of the system. Controlling and modification of the system performance in various conditions is more practical by correlations among the performance factors of the PEMFC derived from fuzzy cognitive maps. On the other hand, the information of fuzzy cognitive map modelling is applicable for modification of neural networks structure for providing more accurate results based on the extracted knowledge from the cognitive map and visualization of the system’s performance. Finally, a rule based fuzzy cognitive map has been used that can be implemented for decision-making to control the system. This rule-based approach provides interpretability while enhancing the performance of the overall system.

  9. Advances in heterocycle synthesis via [3+m]-cycloaddition reactions involving an azaoxyallyl cation as the key intermediate.

    Science.gov (United States)

    Xuan, Jun; Cao, Xia; Cheng, Xiao

    2018-05-17

    Heterocyclic compounds are widely found in many natural isolates and medicinally relevant compounds, as well as some fine chemicals. The development of general and efficient methods for the construction of heterocyclic compounds is one of the most important tasks in synthetic organic chemistry. Along these lines, [3+m]-cycloaddition reactions involving in situ generated azaoxyallyl cations as the 3-atom units have emerged as a powerful method for the synthesis of nitrogen-containing heterocycles. In this feature article, we highlight recent advances in this rapidly growing area, mainly focusing on the reaction design as well as the reaction mechanism.

  10. Structure of radicals produced by γ radiolysis. Part 4. Adamantane matrices doped with various 5-membered heterocyclic molecules

    International Nuclear Information System (INIS)

    Winters, D.L.; Ling, A.C.

    1976-01-01

    The effects of γ-radiolysis at room temperature on adamantane and adamantane-d 16 matrices doped with 5-membered heterocyclic molecules has been examined by X-band electron spin resonance (esr) spectrometry. Radical structures formed from heterocyclic solute molecules are discussed and tentative assignments made. Discussion of possible radical structures derived from selected heterocyclic compounds is included, but unambiguous assignmens of structure cannot be made for these compounds from the esr data obtained. It was noted that perdeuterated adamantane matrices provided superior resolution for esr spectra derived from radicals with a delocalized spin center such as allyl or allenyl species. (author)

  11. Removal of polycyclic aromatic hydrocarbons in soil spiked with model mixtures of petroleum hydrocarbons and heterocycles using biosurfactants from Rhodococcus ruber IEGM 231.

    Science.gov (United States)

    Ivshina, Irina; Kostina, Ludmila; Krivoruchko, Anastasiya; Kuyukina, Maria; Peshkur, Tatyana; Anderson, Peter; Cunningham, Colin

    2016-07-15

    Removal of polycyclic aromatic hydrocarbons (PAHs) in soil using biosurfactants (BS) produced by Rhodococcus ruber IEGM 231 was studied in soil columns spiked with model mixtures of major petroleum constituents. A crystalline mixture of single PAHs (0.63g/kg), a crystalline mixture of PAHs (0.63g/kg) and polycyclic aromatic sulfur heterocycles (PASHs), and an artificially synthesized non-aqueous phase liquid (NAPL) containing PAHs (3.00g/kg) dissolved in alkanes C10-C19 were used for spiking. Percentage of PAH removal with BS varied from 16 to 69%. Washing activities of BS were 2.5 times greater than those of synthetic surfactant Tween 60 in NAPL-spiked soil and similar to Tween 60 in crystalline-spiked soil. At the same time, amounts of removed PAHs were equal and consisted of 0.3-0.5g/kg dry soil regardless the chemical pattern of a model mixture of petroleum hydrocarbons and heterocycles used for spiking. UV spectra for soil before and after BS treatment were obtained and their applicability for differentiated analysis of PAH and PASH concentration changes in remediated soil was shown. The ratios A254nm/A288nm revealed that BS increased biotreatability of PAH-contaminated soils. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Structure and spectroscopic properties of the dimeric copper(I) N-heterocyclic carbene complex [Cu₂(CNC(t-Bu))₂](PF₆)₂.

    Science.gov (United States)

    Riener, Korbinian; Pöthig, Alexander; Cokoja, Mirza; Herrmann, Wolfgang A; Kühn, Fritz E

    2015-08-01

    In recent years, the use of copper N-heterocyclic carbene (NHC) complexes has expanded to fields besides catalysis, namely medicinal chemistry and luminescence applications. In the latter case, multinuclear copper NHC compounds have attracted interest, however, the number of these complexes in the literature is still quite limited. Bis[μ-1,3-bis(3-tert-butylimidazolin-2-yliden-1-yl)pyridine]-1κ(4)C(2),N:N,C(2');2κ(4)C(2),N:N,C(2')-dicopper(I) bis(hexafluoridophosphate), [Cu2(C19H25N5)2](PF6)2, is a dimeric copper(I) complex bridged by two CNC, i.e. bis(N-heterocyclic carbene)pyridine, ligands. Each Cu(I) atom is almost linearly coordinated by two NHC ligands and interactions are observed between the pyridine N atoms and the metal centres, while no cuprophilic interactions were observed. Very strong absorption bands are evident in the UV-Vis spectrum at 236 and 274 nm, and an emission band is observed at 450 nm. The reported complex is a new example of a multinuclear copper NHC complex and a member of a compound class which has only rarely been reported.

  13. The usefulness of GPS bicycle tracking data for evaluating the impact of infrastructure change on cycling behaviour.

    Science.gov (United States)

    Heesch, Kristiann C; Langdon, Michael

    2016-02-01

    Issue addressed A key strategy to increase active travel is the construction of bicycle infrastructure. Tools to evaluate this strategy are limited. This study assessed the usefulness of a smartphone GPS tracking system for evaluating the impact of this strategy on cycling behaviour. Methods Cycling usage data were collected from Queenslanders who used a GPS tracking app on their smartphone from 2013-2014. 'Heat' and volume maps of the data were reviewed, and GPS bicycle counts were compared with surveillance data and bicycle counts from automatic traffic-monitoring devices. Results Heat maps broadly indicated that changes in cycling occurred near infrastructure improvements. Volume maps provided changes in counts of cyclists due to these improvements although errors were noted in geographic information system (GIS) geo-coding of some GPS data. Large variations were evident in the number of cyclists using the app in different locations. These variations limited the usefulness of GPS data for assessing differences in cycling across locations. Conclusion Smartphone GPS data are useful in evaluating the impact of improved bicycle infrastructure in one location. Using GPS data to evaluate differential changes in cycling across multiple locations is problematic when there is insufficient traffic-monitoring devices available to triangulate GPS data with bicycle traffic count data. So what? The use of smartphone GPS data with other data sources is recommended for assessing how infrastructure improvements influence cycling behaviour.

  14. Role of certain plant natural products or gamma radiation in the control of mutagenic activity of some heterocyclic amines

    International Nuclear Information System (INIS)

    Abu Ghadeer, A.R.M.; El-Sedeek, A.B.A.; Salem, A.M.; Abu Zaid, M.M.

    1999-01-01

    The present study was designed to use ames test to evaluate the antimutagenic effect of some natural products on the lever microsomes extracted from rats and incubated with some chemical mutagens (heterocyclic compounds). Male swiss albino rats (120-140 g) were used as the source of liver microsomes. Three natural products (Nigella extract, garlic powder and sesame oil) were used to evaluate their antimutagenic activities on six heterocyclic amines. All the tested natural products exhibited their antimutagenic activities when added to the investigated heterocyclic compounds and the most effective product was nigella sativa. another group of rats was exposed to gamma-radiation (6.5 Gy) for testing the validity of ames test in quantitating mutagenicity using liver microsomes of irradiated rats. Liver microsomes from irradiated rats showed to lose ability for metabolic activation needed for heterocyclic amines to exert their mutagenic effect on salmonella typhimurium

  15. The investigation of hydrogens bonds between sulphur-bearing heterocyclic and proton-donor compounds by IR absorption spectra

    International Nuclear Information System (INIS)

    Narziev, B.N.; Nurulloev, M.; Makhkambaev, D.

    1982-01-01

    In this article the results of intermolecular interaction study of sulfur-containing heterocyclic (thiophene, thiophane) and proton-donar (water, alcohol, carbonic acids, chlorophon) molecules for measuring of IR spectrum absorption of protondonar compounds in soluted shape are presented

  16. Fluoroalkyl Amino Reagents (FARs: A General Approach towards the Synthesis of Heterocyclic Compounds Bearing Emergent Fluorinated Substituents

    Directory of Open Access Journals (Sweden)

    Bruno Commare

    2017-06-01

    Full Text Available Fluorinated heterocycles are important building blocks in pharmaceutical, agrochemical and material sciences. Therefore, organofluorine chemistry has witnessed high interest in the development of efficient methods for the introduction of emergent fluorinated substituents (EFS onto heterocycles. In this context, fluoroalkyl amino reagents (FARs—a class of chemicals that was slightly forgotten over the last decades—has emerged again recently and proved to be a powerful tool for the introduction of various fluorinated groups onto (heteroaromatic derivatives.

  17. Convergent Synthesis of Piperidines by the Union of Conjugated Alkynes with Imines: A Unique Regioselective Bond Construction for Heterocycle Synthesis

    Science.gov (United States)

    Chen, Ming Z.; Micalizio, Glenn C.

    2009-01-01

    A two-step process is described for the union of aromatic imines, conjugated alkynes and aldehydes that results in a stereoselective synthesis of highly substituted piperidines. This synthetic process has been made possible by defining a unique regioselective functionalization of conjugated alkynes that establishes a suitably functionalized substrate for subsequent heterocycle-forming cationic annulation. Given the flexibility of the coupling process, heterocycles can be accessed through a process that establishes up to four stereogenic centers and four fused rings. PMID:19817447

  18. Fluoroalkyl Amino Reagents (FARs): A General Approach towards the Synthesis of Heterocyclic Compounds Bearing Emergent Fluorinated Substituents.

    Science.gov (United States)

    Commare, Bruno; Schmitt, Etienne; Aribi, Fallia; Panossian, Armen; Vors, Jean-Pierre; Pazenok, Sergiy; Leroux, Frédéric R

    2017-06-12

    Fluorinated heterocycles are important building blocks in pharmaceutical, agrochemical and material sciences. Therefore, organofluorine chemistry has witnessed high interest in the development of efficient methods for the introduction of emergent fluorinated substituents (EFS) onto heterocycles. In this context, fluoroalkyl amino reagents (FARs)-a class of chemicals that was slightly forgotten over the last decades-has emerged again recently and proved to be a powerful tool for the introduction of various fluorinated groups onto (hetero)aromatic derivatives.

  19. Stereoselective, nitro-Mannich/lactamisation cascades for the direct synthesis of heavily decorated 5-nitropiperidin-2-ones and related heterocycles

    Directory of Open Access Journals (Sweden)

    Pavol Jakubec

    2012-04-01

    Full Text Available A versatile nitro-Mannich/lactamisation cascade for the direct stereoselective synthesis of heavily decorated 5-nitropiperidin-2-ones and related heterocycles has been developed. A highly enantioenriched substituted 5-nitropiperidin-2-one was synthesised in a four component one-pot reaction combining an enantioselective organocatalytic Michael addition with the diastereoselective nitro-Mannich/lactamisation cascade. Protodenitration and chemoselective reductive manipulation of the heterocycles was used to install contiguous and fully substituted stereocentres in the synthesis of substituted piperidines.

  20. Applying the health action process approach to bicycle helmet use and evaluating a social marketing campaign.

    Science.gov (United States)

    Karl, Florian M; Smith, Jennifer; Piedt, Shannon; Turcotte, Kate; Pike, Ian

    2017-08-05

    Bicycle injuries are of concern in Canada. Since helmet use was mandated in 1996 in the province of British Columbia, Canada, use has increased and head injuries have decreased. Despite the law, many cyclists do not wear a helmet. Health action process approach (HAPA) model explains intention and behaviour with self-efficacy, risk perception, outcome expectancies and planning constructs. The present study examines the impact of a social marketing campaign on HAPA constructs in the context of bicycle helmet use. A questionnaire was administered to identify factors determining helmet use. Intention to obey the law, and perceived risk of being caught if not obeying the law were included as additional constructs. Path analysis was used to extract the strongest influences on intention and behaviour. The social marketing campaign was evaluated through t-test comparisons after propensity score matching and generalised linear modelling (GLM) were applied to adjust for the same covariates. 400 cyclists aged 25-54 years completed the questionnaire. Self-efficacy and Intention were most predictive of intention to wear a helmet, which, moderated by planning, strongly predicted behaviour. Perceived risk and outcome expectancies had no significant impact on intention. GLM showed that exposure to the campaign was significantly associated with higher values in self-efficacy, intention and bicycle helmet use. Self-efficacy and planning are important points of action for promoting helmet use. Social marketing campaigns that remind people of appropriate preventive action have an impact on behaviour. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  1. A review on bicycle and motorcycle rider control with a perspective on handling qualities

    Science.gov (United States)

    Kooijman, J. D. G.; Schwab, A. L.

    2013-11-01

    This paper is a review study on handling and control of bicycles and motorcycles, the so-called single-track vehicles. The first part gives a brief overview on the modelling of the dynamics of single-track vehicles and the experimental validation. The second part focusses on a review of modelling and measuring human rider control. The third part deals with the concepts of handling and manoeuvrability and their experimental validation. Parallels are drawn with the literature on aircraft handling and pilot models. The paper concludes with the open ends and promising directions for future work in the field of handling and control of single-track vehicles.

  2. Gold-catalyzed Bicyclization of Diaryl Alkynes: Synthesis of Polycyclic Fused Indole and Spirooxindole Derivatives.

    Science.gov (United States)

    Cai, Ju; Wu, Bing; Rong, Guangwei; Zhang, Cheng; Qiu, Lihua; Xu, Xinfang

    2018-04-13

    An unprecedented gold-catalyzed bicyclization reaction of diaryl alkynes has been developed for the synthesis of indoles in good to high yields. Mechanistically, this alkyne bifunctionalization transformation was terminated by a stepwise formal X-H insertion reaction to furnish the corresponding polycyclic-frameworks with structural diversity, and the key intermediate 3 H-indole was isolated and characterized for the first time. In addition, further transformation of these generated tetracyclic-indoles with PCC as the oxidant provided straightforward access to the spirooxindoles in high yields.

  3. Two Pilot Studies of the Effect of Bicycling on Balance and Leg Strength among Older Adults

    OpenAIRE

    Rissel, Chris; Passmore, Erin; Mason, Chloe; Merom, Dafna

    2013-01-01

    Objectives. Study 1 examines whether age-related declines in balance are moderated by bicycling. Study 2 tests whether regular cycling can increase leg strength and improve balance. Methods. Study 1: a cross-sectional survey of 43 adults aged 44–79 was conducted. Leg strength was measured, and Balance was measured using the choice stepping reaction time (CSRT) test (decision time and response time), leg strength and timed single leg standing. Study 2: 18 older adults aged 49–72 were recruited...

  4. Relationship between the Pedaling Biomechanics and Strain of Bicycle Frame during Submaximal Tests

    OpenAIRE

    Manolova, Aneliya; Crequy, Samuel; Lestriez, Philippe; Debraux, Pierre; Bertucci, William

    2015-01-01

    The aim of this study was to analyse the effect of forces applied to pedals and cranks on the strain imposed to an instrumented bicycle motocross (BMX) frame. Using results from a finite element analysis to determine the localisation of highest stress, eight strain gauges were located on the down tube, the seat tube and the right chain stay. Before the pedaling tests, static loads were applied to the frame during bench tests. Two pedaling conditions have been analysed. In the first, the rider...

  5. Understanding adolescents' intentions to commute by car or bicycle as adults

    DEFF Research Database (Denmark)

    Sigurdardottir, Sigrun Birna; Kaplan, Sigal; Møller, Mette

    2013-01-01

    This study focuses on the intentions of adolescents to commute by car or bicycle as adults. The behavioral model is based on intrapersonal and interpersonal constructs from the theory of planned behavior extended to include constructs from the institutional, community and policy domains. Data from...... a survey among Danish adolescents is analyzed. It is found that car use intentions are related to positive car passenger experience, general interest in cars, and car ownership norms, and are negatively related to willingness to accept car restrictions and perceived lack of behavioral control. Cycling...

  6. Wittig Reaction: Domino Olefination and Stereoselectivity DFT Study. Synthesis of the Miharamycins' Bicyclic Sugar Moiety.

    Science.gov (United States)

    Cachatra, Vasco; Almeida, Andreia; Sardinha, João; Lucas, Susana D; Gomes, Ana; Vaz, Pedro D; Florêncio, M Helena; Nunes, Rafael; Vila-Viçosa, Diogo; Calhorda, Maria José; Rauter, Amélia P

    2015-11-20

    2-O-Acyl protected-d-ribo-3-uloses reacted with [(ethoxycarbonyl)methylene]triphenylphosphorane in acetonitrile to afford regio- and stereoselectively 2-(Z)-alkenes in 10-60 min under microwave irradiation. This domino reaction is proposed to proceed via tautomerization of 3-ulose to enol, acyl migration, tautomerization to the 3-O-acyl-2-ulose, and Wittig reaction. Alternatively, in chloroform, regioselective 3-olefination of 2-O-pivaloyl-3-uloses gave (E)-alkenes, key precursors for the miharamycins' bicyclic sugar moiety.

  7. Ergonomic Analysis of UI’s BicyclesUsing Posture Evaluation Index (PEI Method in Virtual Environment

    Directory of Open Access Journals (Sweden)

    Erlinda Muslim

    2010-10-01

    Full Text Available This research was conducted to study ergonomic aspect from University of Indonesia bicycle in virtual environment. Software Jack 6.0 was used to analyze it. PEI was used as approach that integrated the results of three methods: Lower Back Analysis, Ovako Working Posture Analysis, and Rapid Upper Limb Assessment. The research objective is to evaluate existing design of University of Indonesia bicycle and to determine the most ergonomic redesign which concern with handlebar height and saddle height modification. The result showed that the most ergonomic design of University of Indonesia bicycle is the one with the highest handlebar height (22 cm and the lowest saddle height (11 cm.

  8. N-Heterocyclic-Carbene-Treated Gold Surfaces in Pentacene Organic Field-Effect Transistors: Improved Stability and Contact at the Interface.

    Science.gov (United States)

    Lv, Aifeng; Freitag, Matthias; Chepiga, Kathryn M; Schäfer, Andreas H; Glorius, Frank; Chi, Lifeng

    2018-04-16

    N-Heterocyclic carbenes (NHCs), which react with the surface of Au electrodes, have been successfully applied in pentacene transistors. With the application of NHCs, the charge-carrier mobility of pentacene transistors increased by five times, while the contact resistance at the pentacene-Au interface was reduced by 85 %. Even after annealing the NHC-Au electrodes at 200 °C for 2 h before pentacene deposition, the charge-carrier mobility of the pentacene transistors did not decrease. The distinguished performance makes NHCs as excellent alternatives to thiols as metal modifiers for the application in organic field-effect transistors (OFETs). © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Exercise capacity in non-specific chronic low back pain patients : A lean body mass-based Astrand bicycle test; Reliability, validity and feasibility

    NARCIS (Netherlands)

    Hodselmans, Audy P.; Dijkstra, Pieter U.; Geertzen, Jan H. B.; van der Schans, Cees P.

    Objective Measurement of exercise capacity is essential in patients with non-specific chronic low back pain (CLBP). However, the conventional Astrand bicycle test is not feasible in patients with a very poor aerobic capacity. Therefore the Astrand bicycles test for non-specific CLBP patients based

  10. One-Pot Two-Step Multicomponent Process of Indole and Other Nitrogenous Heterocycles or Amines toward α-Oxo-acetamidines.

    Science.gov (United States)

    Martinez-Ariza, Guillermo; McConnell, Nicholas; Hulme, Christopher

    2016-04-15

    A cesium carbonate promoted three-component reaction of N-H containing heterocycles, primary or secondary amines, arylglyoxaldehydes, and anilines is reported. The key step involves a tandem sequence of N-1 addition of a heterocycle or an amine to preformed α-iminoketones, followed by an air- or oxygen-mediated oxidation to form α-oxo-acetamidines. The scope of the reaction is enticingly broad, and this novel methodology is applied toward the synthesis of various polycyclic heterocycles.

  11. Two food-borne heterocyclic amines: Metabolism and DNA adduct formation of amino-alpha-carbolines

    DEFF Research Database (Denmark)

    Frederiksen, Hanne

    2005-01-01

    or proteins of animal or vegetable origin, furthermore they are found in many cooked foods, such as fish, meat, and chicken. The specific mutagenicity of the amino-a-carbolines are lower in the Ames Salmonella assay than other heterocyclic amines, but in rodent studies the carcinogenicity of the aminoa, alpha......The amino-alpha-carbolines 2-amino-9H-pyrido[2,3-b]indole (A alpha C) and 2-amino-3-methyl-9H-pyrido-[2,3-b]indole (MeA alpha C) are two mutagenic and carcinogenic heterocyclic amines formed during ordinary cooking. Amino-alpha-carbolines can be formed in model systems by pyrolyzing tryptophan...

  12. Direct Functionalization of Nitrogen Heterocycles via Rh-Catalyzed C-H Bond Activation

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, Jared; Bergman, Robert; Ellman, Jonathan

    2008-02-04

    Nitrogen heterocycles are present in many compounds of enormous practical importance, ranging from pharmaceutical agents and biological probes to electroactive materials. Direct funtionalization of nitrogen heterocycles through C-H bond activation constitutes a powerful means of regioselectively introducing a variety of substituents with diverse functional groups onto the heterocycle scaffold. Working together, our two groups have developed a family of Rh-catalyzed heterocycle alkylation and arylation reactions that are notable for their high level of functional-group compatibility. This Account describes their work in this area, emphasizing the relevant mechanistic insights that enabled synthetic advances and distinguished the resulting transformations from other methods. They initially discovered an intramolecular Rh-catalyzed C-2-alkylation of azoles by alkenyl groups. That reaction provided access to a number of di-, tri-, and tetracyclic azole derivatives. They then developed conditions that exploited microwave heating to expedite these reactions. While investigating the mechanism of this transformation, they discovered that a novel substrate-derived Rh-N-heterocyclic carbene (NHC) complex was involved as an intermediate. They then synthesized analogous Rh-NHC complexes directly by treating precursors to the intermediate [RhCl(PCy{sub 3}){sub 2}] with N-methylbenzimidazole, 3-methyl-3,4-dihydroquinazolein, and 1-methyl-1,4-benzodiazepine-2-one. Extensive kinetic analysis and DFT calculations supported a mechanism for carbene formation in which the catalytically active RhCl(PCy{sub 3}){sub 2} fragment coordinates to the heterocycle before intramolecular activation of the C-H bond occurs. The resulting Rh-H intermediate ultimately tautomerizes to the observed carbene complex. With this mechanistic information and the discovery that acid co-catalysts accelerate the alkylation, they developed conditions that efficiently and intermolecularly alkylate a variety of

  13. Synthesis of heterocycles via transition-metal-catalyzed hydroarylation of alkynes.

    Science.gov (United States)

    Yamamoto, Yoshihiko

    2014-03-07

    Transition-metal (TM)-catalyzed hydroarylation reactions of alkynes have received much attention, because they enable the net insertion of alkyne C-C triple bonds into C-H bonds of aromatic precursors, resulting in regio- and stereo-selective formation of synthetically useful arylalkenes. Taking advantage of this feature, TM-catalyzed alkyne hydroarylations have been successfully used for the synthesis of heterocycles. TM-catalyzed alkyne hydroarylations can be classified into three major categories depending on the type of reaction and precursors involved: (1) palladium-catalyzed reductive Heck reactions of alkynes with aryl halides, (2) TM-catalyzed conjugate arylation reactions of activated alkynes with arylboronic acids, and (3) TM-catalyzed aromatic C-H alkenylations with alkynes. This review surveys heterocycle synthesis via TM-catalyzed hydroarylation of alkynes according to the above classification, with an emphasis on the scope and limitations, as well as the underlying mechanisms.

  14. Anaerobic biodegradation of halogenated and nonhalogenated N-, s-, and o-heterocyclic compounds in aquifer slurries

    Science.gov (United States)

    Adrian, Neal R.; Suflita, Joseph M.

    1994-01-01

    The fate of several halogenated and nonhalogenated heterocyclic compounds in anoxic aquifer slurries was investigated Substrate depletion and methane formation were monitored in serum bottle incubations by HPLC and GC, respectively Pyridine, pyrimidine, thiophene, and furan were not mineralized following an 11-month incubation, but the corresponding carboxylated or oxygenated compounds were That is, >74% of the theoretically expected amount of methane was recovered from nicotinic acid, uracil, or 2-furoic acid Chlorinated derivatives, like 2 chloro- or 6-chloronicotinic acid, as well as 4 chloro- and 5-chlorouracil resisted mineralization However, 5-bromouracil was reductively dehalogenated to stoichiometric amounts of uracil, whereas 2-chloropyrimidine was metabolized to a more polar unidentified compound that resisted further anaerobic biodegradation Microorganisms acclimated to 5-bromouracil were unable to transform 4 chloro or 5 chlorouracil These findings illustrate how the structure of heterocyclic contaminants influences their susceptibility to anaerobic decay

  15. Mn(III)-initiated facile oxygenation of heterocyclic 1,3-dicarbonyl compounds.

    Science.gov (United States)

    Rahman, Md Taifur; Haque, Md Aminul; Igarashi, Hikaru; Nishino, Hiroshi

    2011-11-16

    The Mn(III)-initiated aerobic oxidation of heterocyclic 1,3-dicarbonyl compounds, such as 4-alkyl-1,2-diphenylpyrazolidine-3,5-diones, 1,3-dialkylpyrrolidine-2,4-diones, 3-alkyl-1,5-dimethylbarbituric acids, and 3-butyl-4-hydroxy-2-quinolinone gave excellent to good yields of the corresponding hydroperoxides, which were gradually degraded by exposure to the metal initiator after the reaction to afford the corresponding alcohols. The synthesis of 30 heterocyclic 1,3-dicarbonyl compounds, the corresponding hydroperoxides and the 10 alcohols, their characterization, and the limitations of the procedure are described. In addition, the mechanism of the hydroperoxidation and the redox decomposition of the hydroperoxides are discussed.

  16. Interpretation of electronic spectra of ruthenium nitroso complexes with N-heterocyclic ligands

    International Nuclear Information System (INIS)

    Sizova, O.V.; Ivanova, N.V.; Lyubimova, O.O.; Nikol'skij, A.B.

    2004-01-01

    Relaying on ab initio and semiempirical CINDO/CI calculations of free ligands L and complexes trans-[Ru(NO)(NH 3 ) 4 (L)] 3+ (L=pyridine, pyrazine, nicotinamide, l-histidine, imidazole), electronic absorption spectra of nitroso complexes with nitrogen-containing heterocyclic ligands L have been analyzed. Spectral manifestations of strong covalent bond Ru-NO was pointed out and the conclusion was made about advisability of presentation of Ru and NO oxidation states in grouping RuNO 3+ as Ru(III) and NO 0 . Introduction of nitroso group into inner coordination sphere of Ru(II) complexes with nitrogen-containing heterocyclic ligands results in essential rearrangement of the entire structure and deprives ligands L of their ability to manifest chromophore properties [ru

  17. Abiotic synthesis of purines and other heterocyclic compounds by the action of electrical discharges

    Science.gov (United States)

    Yuasa, S.; Flory, D.; Basile, B.; Oro, J.

    1984-01-01

    The synthesis of purines and pyrimidines using Oparin-Urey-type primitive earth atmospheres has been demonstrated by reacting methane, ethane, and ammonia in electrical discharges. Adenine, guaine, 4-aminoimidazole-5-carboxamide (AICA), and isocytosine have been identified by UV spectrometry and paper chromatography as the products of the reaction. The total yields of the identified heterocyclic compounds are 0.0023 percent. It is concluded that adenine synthesis occurs at a much lower concentration of hydrogen cyanide than has been shown by earlier studies. Pathways for the synthesis of purines from hydrogen cyanide are discussed, and a comparison of the heterocyclic compounds that have been identified in meteorites and in prebiotic reactions is presented.

  18. Far IR spectra of Th(IV) halide complexes of some heterocyclic bases

    International Nuclear Information System (INIS)

    Srivastava, A.K.; Agarwal, R.K.; Srivastava, M.; Kapoor, V.; Srivastava, T.N.

    1981-01-01

    The synthesis and IR spectra of Th(IV) perchlorato, nitrato and thiocyanato complexes of some heterocyclic bases have been reported. Halogens are common ligands in coordination chemistry forming coordinate bonds with metals readily. Metal halogen (M-X) stretching bands show a strong absorption in the far-IR region. Very little information is available on Th-X stretching frequencies. In the present communication, adducts of Th(IV) halide with certain nitrogen heterocyclic bases such as pyridine, α-picoline, 2-amino pyridine, 2:4-lutidine, 2:6-lutidine, quinoline, 2,2'-bipyridine and 1,10-phenanthroline were synthesised and characterised. Experimental details are given. Results are presented and discussed. (author)

  19. Reaction of vanadocene and its monochloride with salts of nitrogen-containing heterocycles

    International Nuclear Information System (INIS)

    Gordetsov, A.S.; Pereshein, V.V.; Lyatyaeva, V.N.; Mar'in, V.P.; Rukevich, OS.; Zakharova, E.S.

    1985-01-01

    The reaction of bis(eta 5 -cyclopentadienyl) vanadium (Cp 2 V) and its monochloride with diallyl isocyanurates of Ag and alkali metals and with Ag salt of succinimide is used for preparing almost inaccessible Cp 2 V-substituted nitrogen-containing heterocycles. The reactions have been performed in toluene in an evacuated ampoule at room temperature and at 120-130 deg C in case of diallyl isocyanurates of alkali metals. Reaction yields element analysis data, DTA, IR spectra and ESR spectra. Cp 2 V easily reduces Ag from its salts with nitrogen-containing heterocycles oxidizing with production of V(3) sandwich derivatives In exchange reactions of Cp 2 VCl with diallyl isocyanurate salts of alkali metals and silver Cp 2 V-diallyl isocyanurate with an oxo-structure is prosduced as well. The produced AgCl subsequently oxidizers Cp 2 VCl up to Cp 2 VCl 2

  20. Mn(III-Initiated Facile Oxygenation of Heterocyclic 1,3-Dicarbonyl Compounds

    Directory of Open Access Journals (Sweden)

    Md. Aminul Haque

    2011-11-01

    Full Text Available The Mn(III-initiated aerobic oxidation of heterocyclic 1,3-dicarbonyl compounds, such as 4-alkyl-1,2-diphenylpyrazolidine-3,5-diones, 1,3-dialkylpyrrolidine-2,4-diones, 3-alkyl-1,5-dimethylbarbituric acids, and 3-butyl-4-hydroxy-2-quinolinone gave excellent to good yields of the corresponding hydroperoxides, which were gradually degraded by exposure to the metal initiator after the reaction to afford the corresponding alcohols. The synthesis of 30 heterocyclic 1,3-dicarbonyl compounds, the corresponding hydroperoxides and the 10 alcohols, their characterization, and the limitations of the procedure are described. In addition, the mechanism of the hydroperoxidation and the redox decomposition of the hydroperoxides are discussed.