WorldWideScience

Sample records for stable non-toxic compounds

  1. Stable isotopes labelled compounds

    International Nuclear Information System (INIS)

    1982-09-01

    The catalogue on stable isotopes labelled compounds offers deuterium, nitrogen-15, and multiply labelled compounds. It includes: (1) conditions of sale and delivery, (2) the application of stable isotopes, (3) technical information, (4) product specifications, and (5) the complete delivery programme

  2. Polymer Solar Cells – Non Toxic Processing and Stable Polymer Photovoltaic Materials

    DEFF Research Database (Denmark)

    Søndergaard, Roar

    The field of polymer solar cell has experienced enormous progress in the previous years, with efficiencies of small scale devices (~1 mm2) now exceeding 8%. However, if the polymer solar cell is to achieve success as a renewable energy resource, mass production of sufficiently stable and efficient...... and development of more stable materials. The field of polymer solar cells has evolved around the use of toxic and carcinogenic solvents like chloroform, benzene, toluene, chlorobenzene, dichlorobenzene and xylene. As large scale production of organic solar cells is envisaged to production volumes corresponding...... synthesis of polymers carrying water coordinating side chains which allow for processing from semi-aqueous solution. A series of different side chains were synthesized and incorporated into the final polymers as thermocleavable tertiary esters. Using a cleavable side chain induces stability to solar cells...

  3. Polymer solar cells - Non toxic processing and stable polymer photovoltaic materials

    Energy Technology Data Exchange (ETDEWEB)

    Soendergaard, R

    2012-07-01

    The field of polymer solar cell has experienced enormous progress in the previous years, with efficiencies of small scale devices (approx1 mm2) now exceeding 8%. However, if the polymer solar cell is to achieve success as a renewable energy resource, mass production of sufficiently stable and efficient cell must be achieved. For a continuous success it is therefore essential to transfer the accomplishments from the laboratory to large scale facilities for actual production. In order to do so, several issues have to be approached. Among these are more environmentally friendly processing and development of more stable materials. The field of polymer solar cells has evolved around the use of toxic and carcinogenic solvents like chloroform, benzene, toluene, chlorobenzene, dichlorobenzene and xylene. As large scale production of organic solar cells is envisaged to production volumes corresponding to several GW{sub peek}, this is not a suitable approach from neither a production nor environmental point of view. As a consequence new materials, which can be processed from more environmentally friendly solvents (preferably water), need to be developed. In this thesis, the issue has been approached through synthesis of polymers carrying water coordinating side chains which allow for processing from semi-aqueous solution. A series of different side chains were synthesized and incorporated into the final polymers as thermocleavable tertiary esters. Using a cleavable side chain induces stability to solar cells as it slows down diffusion though the active layer, but just as important it renders the layer insoluble. This allows for further processing, using the same solvent, without dissolving already processed layers, and resulted in the first ever reported solar cells where all layers are processed from aqueous or semi-aqueous solution. As previously mentioned many advantages can be achieved by use of thermocleavable materials. Unfortunately the cleavage temperatures are too

  4. Platinum nanoparticles: a non-toxic, effective and thermally stable alternative plasmonic material for cancer therapy and bioengineering.

    Science.gov (United States)

    Samadi, Akbar; Klingberg, Henrik; Jauffred, Liselotte; Kjær, Andreas; Bendix, Poul Martin; Oddershede, Lene B

    2018-05-17

    Absorption of near infrared (NIR) light by metallic nanoparticles can cause extreme heating and is of interest for instance in cancer treatment since NIR light has a relatively large penetration depth into biological tissue. Here, we quantify the extraordinary thermoplasmonic properties of platinum nanoparticles and demonstrate their efficiency in photothermal cancer therapy. Although platinum nanoparticles are extensively used for catalysis, they are much overlooked in a biological context. Via direct measurements based on a biological matrix we show that individual irradiated platinum nanoparticles with diameters of 50-70 nm can easily reach surface temperatures up to 900 K. In contrast to gold nanoshells, which are often used for photothermal purposes, we demonstrate that the platinum particles remain stable at these extreme temperatures. The experiments are paralleled by finite element modeling confirming the experimental results and establishing a theoretical understanding of the particles' thermoplasmonic properties. At extreme temperatures it is likely that a vapor layer will form around the plasmonic particle, and we show this scenario to be consistent with direct measurements and simulations. Viability studies demonstrate that platinum nanoparticles themselves are non-toxic at therapeutically relevant concentrations, however, upon laser irradiation we show that they efficiently kill human cancer cells. Therefore, platinum nanoparticles are highly promising candidates for thermoplasmonic applications in the life sciences, in nano-medicine, and for bio-medical engineering.

  5. Discovery of potent, novel, non-toxic anti-malarial compounds via quantum modelling, virtual screening and in vitro experimental validation

    Directory of Open Access Journals (Sweden)

    Kaludov Nikola

    2011-09-01

    Full Text Available Abstract Background Developing resistance towards existing anti-malarial therapies emphasize the urgent need for new therapeutic options. Additionally, many malaria drugs in use today have high toxicity and low therapeutic indices. Gradient Biomodeling, LLC has developed a quantum-model search technology that uses quantum similarity and does not depend explicitly on chemical structure, as molecules are rigorously described in fundamental quantum attributes related to individual pharmacological properties. Therapeutic activity, as well as toxicity and other essential properties can be analysed and optimized simultaneously, independently of one another. Such methodology is suitable for a search of novel, non-toxic, active anti-malarial compounds. Methods A set of innovative algorithms is used for the fast calculation and interpretation of electron-density attributes of molecular structures at the quantum level for rapid discovery of prospective pharmaceuticals. Potency and efficacy, as well as additional physicochemical, metabolic, pharmacokinetic, safety, permeability and other properties were characterized by the procedure. Once quantum models are developed and experimentally validated, the methodology provides a straightforward implementation for lead discovery, compound optimizzation and de novo molecular design. Results Starting with a diverse training set of 26 well-known anti-malarial agents combined with 1730 moderately active and inactive molecules, novel compounds that have strong anti-malarial activity, low cytotoxicity and structural dissimilarity from the training set were discovered and experimentally validated. Twelve compounds were identified in silico and tested in vitro; eight of them showed anti-malarial activity (IC50 ≤ 10 μM, with six being very effective (IC50 ≤ 1 μM, and four exhibiting low nanomolar potency. The most active compounds were also tested for mammalian cytotoxicity and found to be non-toxic, with a

  6. Non-toxic brominated perfluorocarbons radiopaque agents

    International Nuclear Information System (INIS)

    Long, D.M. Jr.

    1976-01-01

    Non-toxic bromofluorocarbon radiopaque agents are disclosed. Certain monobrominated acyclic fluorocarbons, e.g., CF 3 (CF 2 ) 6 CF 2 Br, are improved non-toxic radiopaque agents useful in diagnostic roentgenology, for example in visualizing the gastrointestinal tract, the tracheobronchial tree, the alveolar spaces or parenchyma of the lung, the spleen, the urinary bladder and ureters, the common bile duct and its radicals, the pancreatic ducts, the blood vessels, etc. 13 claims, no drawings

  7. Application of AOPs for Removal of Stable Cyanide Compounds

    Science.gov (United States)

    Tsybikova, B.

    2017-11-01

    The main kinetic regularities of the photochemical oxidation of stable cyanide compounds (exemplified by hexacyanoferrates) by combined treatments involving direct photolysis and persulfate (oxidative system UV/S2O8 2-) and direct photolysis and hydrogen peroxide (oxidative system UV/H2O2) were studied. The possibility to perform oxidation processes within a wide pH range was shown. Based on to the energy efficiency, the rate of reaction and duration of the treatment, the considered oxidative systems can be arranged in the following order: {UV/S2O8 2-}>{UV/H2O2}>{UV}. The enhanced efficiency of hexacyanoferrates’ degradation by the combined system {UV/S2O8 2-} is due to the high oxidative capacity of sulfate anion radicals SO4 -· formed as a result of persulfate photolysis and its further disproportionation by Fe3+ and Fe2+ released through the decomposition of [Fe(CN)6]3-. Furthermore, the formation of ·OH radicals as a result of SO4 -· reacting with water also contributes to the enhanced oxidation efficiency. The combined method of {UV/S2O8 2-} treatment could be applied for the treatment of cyanide-containing wastewater and recycled water of different industries.

  8. Characterization of phenols biodegradation by compound specific stable isotope analysis

    Science.gov (United States)

    Wei, Xi; Gilevska, Tetyana; Wenzig, Felix; Hans, Richnow; Vogt, Carsten

    2015-04-01

    -cresol degradation and 2.2±0.3‰ for m-cresol degradation, respectively. The carbon isotope fractionation patterns of phenol degradation differed more profoundly. Oxygen-dependent monooxygenation of phenol by A.calcoaceticus as the initial reaction yielded ƐC values of -1.5±0.02‰. In contrast, the anaerobic degradation initiated by ATP-dependent carboxylation performed by Thauera aromatia DSM 6984, produced no detectable fractionation (ƐC 0±0.1‰). D. cetonica showed a slight inverse carbon isotope fractionation (ƐC 0.4±0.1‰). In conclusion, a validated method for compound specific stable isotope analysis was developed for phenolic compounds, and the first data set of carbon enrichment factors upon the biodegradation of phenol and cresols with different activation mechanisms has been obtained in the present study. Carbon isotope fractionation analysis is a potentially powerful tool to monitor phenolic compounds degradation in the environment.

  9. Non-Toxic, Non-Flammable, -80 C Phase Change Materials

    Science.gov (United States)

    Cutbirth, J. Michael

    2013-01-01

    The objective of this effort was to develop a non-toxic, non-flammable, -80 C phase change material (PCM) to be used in NASA's ICEPAC capsules for biological sample preservation in flight to and from Earth orbit. A temperature of about -68 C or lower is a critical temperature for maintaining stable cell, tissue, and cell fragment storage.

  10. Non-Toxic HAN Monopropellant Propulsion, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Non-toxic monopropellants have been developed that provide better performance than toxic hydrazine. Formulations based on hydroxylammonium nitrate (HAN) have...

  11. Non-Toxic, Low-Freezing, Drop-In Replacement Heat Transfer Fluids

    Science.gov (United States)

    Cutbirth, J. Michael

    2012-01-01

    A non-toxic, non-flammable, low-freezing heat transfer fluid is being developed for drop-in replacement within current and future heat transfer loops currently using water or alcohol-based coolants. Numerous water-soluble compounds were down-selected and screened for toxicological, physical, chemical, compatibility, thermodynamic, and heat transfer properties. Two fluids were developed, one with a freezing point near 0 C, and one with a suppressed freezing point. Both fluids contain an additive package to improve material compatibility and microbial resistance. The optimized sub-zero solution had a freezing point of 30 C, and a freezing volume expansion of 10-percent of water. The toxicity of the solutions was experimentally determined as LD(50) greater than 5g/kg. The solutions were found to produce minimal corrosion with materials identified by NASA as potentially existing in secondary cooling loops. Thermal/hydrodynamic performance exceeded that of glycol-based fluids with comparable freezing points for temperatures Tf greater than 20 C. The additive package was demonstrated as a buffering agent to compensate for CO2 absorption, and to prevent microbial growth. The optimized solutions were determined to have physically/chemically stable shelf lives for freeze/thaw cycles and longterm test loop tests.

  12. [Glyphosate--a non-toxic pesticide?].

    Science.gov (United States)

    Pieniazek, Danuta; Bukowska, Bozena; Duda, Wirgiliusz

    2003-01-01

    Glyphosate is currently the most commonly applied herbicide and its use is still growing. Nowadays, over 50 commercial preparations containing this compound are used, and these formulations are much more toxic than their active compound, glyphosate, owing to the presence of many surfactants and carrier compounds. Toxicological investigations provide evidence that glyphosate is an extremely "safe" herbicide for animals. This is why its use in agriculture is universal. In June 1991, the Environmental Protection Agency (EPA) categorized this compound into class E (according to EPA there are five categories of carcinogenicity), which means that it is probably not carcinogenic to humans. Unfortunately, the study carried out by Swedish oncologists in 2001 showed that glyphosate may induce cancer of the lymphatic system. The results of the Swedish study have changed our opinion about "safety" of this herbicide. Investigations concerning both its accumulation and toxic effect in animals and plants are now under way in many laboratories.

  13. A non-toxic fluorogenic dye for mitochondria labeling.

    Science.gov (United States)

    Han, Junyan; Han, Myung Shin; Tung, Ching-Hsuan

    2013-11-01

    Mitochondria, powerhouses of cells, are responsible for many critical cellular functions, such as cell energy metabolism, reactive oxygen species production, and apoptosis regulation. Monitoring mitochondria morphology in live cells temporally and spatially could help with the understanding of the mechanisms of mitochondrial functional regulation and the pathogenesis of mitochondria-related diseases. A novel non-cytotoxic fluorogenic compound, AcQCy7, was developed as a mitochondria-specific dye. AcQCy7 emitted no fluorescent signal outside of cells, but it became fluorescent after intracellular hydrolysis of the acetyl group. The hydrolyzed fluorescent product was well retained in mitochondria, enabling long-lasting fluorescence imaging of mitochondria without cell washing. A 2-day culture study using AcQCy7 showed no sign of cytotoxicity, whereas a commonly used mitochondria-staining probe, Mitochondria Tracker Green, caused significant cell death even at a much lower concentration. Apoptosis-causing mitochondria fission was monitored clearly in real time by AcQCy7. A simple add-and-read mitochondria specific dye AcQCy7 has been validated in various cell models. Bright mitochondria specific fluorescent signal in treated cells lasted several days without noticeable toxicity. The probe AcQCy7 has been proofed to be a non-toxic agent for long-term mitochondria imaging. © 2013.

  14. Evaluation of genetic diversity between toxic and non toxic Jatropha ...

    African Journals Online (AJOL)

    Massimo

    Indian varieties and a non-toxic variety of Mexican origin by means of about 400 RAPD ... evaluate the level of polymorphism and the capacity to discriminate between the ..... Population genetic software for teaching and research. Mol. Ecol.

  15. 100-lbf Non-Toxic Storable Liquid Propulsion, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's Road Maps for both Launch and In Space Propulsion call for the development of non-toxic, monopropellant reaction control systems to replace current...

  16. Thyroid cancer in toxic and non-toxic multinodular goiter

    Directory of Open Access Journals (Sweden)

    Cerci C

    2007-01-01

    Full Text Available Background : Many authors have claimed that hyperthyroidism protects against thyroid cancer and believed that the incidence of malignancy is lower in patients with toxic multinodular goiter (TMG than in those with non-toxic multinodular goiter. But in recent studies, it was reported that the incidence of malignancy with TMG is not as low as previously thought. Aim : To compare the thyroid cancer incidence in patients with toxic and non-toxic multinodular goiter. Settings and Design : Histology reports of patients treated surgically with a preoperative diagnosis of toxic and non-toxic multinodular goiter were reviewed to identify the thyroid cancer incidence. Patients having a history of neck irradiation or radioactive iodine therapy were excluded from the study. Materials and Methods : We reviewed 294 patients operated between 2001-2005 from toxic and non-toxic multinodular goiter. One hundred and twenty-four of them were toxic and 170 were non-toxic. Hyperthyroidism was diagnosed by elevated tri-iodothyroinine / thyroxine ratios and low thyroid-stimulating hormone with clinical signs and symptoms. All patients were evaluated with ultrasonography and scintigraphy and fine needle aspiration biopsy. Statistical Analysis Used : Significance of the various parameters was calculated by using ANOVA test. Results : The incidence of malignancy was 9% in the toxic and 10.58% in the non-toxic multinodular goiter group. Any significant difference in the incidence of cancer and tumor size between the two groups could not be detected. Conclusions : The incidence of malignancy in toxic multinodular goiter is not very low as thought earlier and is nearly the same in non-toxic multinodular goiter.

  17. Stable Isotope Fractionation Caused by Glycyl Radical Enzymes during Bacterial Degradation of Aromatic Compounds

    Science.gov (United States)

    Morasch, Barbara; Richnow, Hans H.; Vieth, Andrea; Schink, Bernhard; Meckenstock, Rainer U.

    2004-01-01

    Stable isotope fractionation was studied during the degradation of m-xylene, o-xylene, m-cresol, and p-cresol with two pure cultures of sulfate-reducing bacteria. Degradation of all four compounds is initiated by a fumarate addition reaction by a glycyl radical enzyme, analogous to the well-studied benzylsuccinate synthase reaction in toluene degradation. The extent of stable carbon isotope fractionation caused by these radical-type reactions was between enrichment factors (ɛ) of −1.5 and −3.9‰, which is in the same order of magnitude as data provided before for anaerobic toluene degradation. Based on our results, an analysis of isotope fractionation should be applicable for the evaluation of in situ bioremediation of all contaminants degraded by glycyl radical enzyme mechanisms that are smaller than 14 carbon atoms. In order to compare carbon isotope fractionations upon the degradation of various substrates whose numbers of carbon atoms differ, intrinsic ɛ (ɛintrinsic) were calculated. A comparison of ɛintrinsic at the single carbon atoms of the molecule where the benzylsuccinate synthase reaction took place with compound-specific ɛ elucidated that both varied on average to the same extent. Despite variations during the degradation of different substrates, the range of ɛ found for glycyl radical reactions was reasonably narrow to propose that rough estimates of biodegradation in situ might be given by using an average ɛ if no fractionation factor is available for single compounds. PMID:15128554

  18. Cooperation of CMEA member states in the field of the manufacture and use of stable isotopes and compounds thus labelled

    International Nuclear Information System (INIS)

    Ertel, G.; Ewald, G.

    1977-01-01

    The contribution presents a survey of scientific-technical cooperation of CMEA member states in the field of stable isotopes, it deals with the specialization of stable isotope production and compounds thus labelled, and gives the prospects for further development of this cooperation. (HK) [de

  19. Separation of polybrominated diphenyl ethers in fish for compound-specific stable carbon isotope analysis

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Yan-Hong [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Graduate University of Chinese Academy of Sciences, Beijing, 100049 (China); Luo, Xiao-Jun, E-mail: luoxiaoj@gig.ac.cn [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Chen, Hua-Shan; Wu, Jiang-Ping; Chen, She-Jun; Mai, Bi-Xian [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)

    2012-05-15

    A separation and isotopic analysis method was developed to accurately measure the stable carbon isotope ratios of polybrominated diphenyl ethers (PBDEs) with three to six substituted bromine atoms in fish samples. Sample extracts were treated with concentrated sulfuric acid to remove lipids, purified using complex silica gel column chromatography, and finally processed using alumina/silica (Al/Si) gel column chromatography. The purities of extracts were verified by gas chromatography and mass spectrometry (GC-MS) in the full-scan mode. The average recoveries of all compounds across the purification method were between 60% and 110%, with the exception of BDE-154. The stable carbon isotopic compositions of PBDEs can be measured with a standard deviation of less than 0.5 Per-Mille-Sign . No significant isotopic fraction was found during the purification of the main PBDE congeners. A significant change in the stable carbon isotope ratio of BDE-47 was observed in fish carcasses compared to the original isotopic signatures, implying that PBDE stable carbon isotopic compositions can be used to trace the biotransformation of PBDEs in biota. - Highlights: Black-Right-Pointing-Pointer A method for the purification of PBDEs for CSIA was developed. Black-Right-Pointing-Pointer The {delta}{sup 13}C of PBDE congeners can be measured with a standard deviation of less than 0.5 Per-Mille-Sign . Black-Right-Pointing-Pointer Common carp were exposed to a PBDE mixture to investigate debromination. Black-Right-Pointing-Pointer Ratios of the {delta}{sup 13}C values can be used to trace the debromination of PBDE in fish.

  20. Children's Ability to Recognise Toxic and Non-Toxic Fruits

    Science.gov (United States)

    Fancovicova, Jana; Prokop, Pavol

    2011-01-01

    Children's ability to identify common plants is a necessary prerequisite for learning botany. However, recent work has shown that children lack positive attitudes toward plants and are unable to identify them. We examined children's (aged 10-17) ability to discriminate between common toxic and non-toxic plants and their mature fruits presented in…

  1. {sup 131}I treatment of nodular non-toxic goitre

    Energy Technology Data Exchange (ETDEWEB)

    Nygaard, B.; Faber, J.; Hegdeues, L.; Hansen, J.M. [Herlev Hospital (Denmark)

    1996-01-01

    The traditional treatment of a growing nodular non-toxic goitre has for many years been surgical resection or levothyroxine suppressive treatment. During recent years, several studies have reported promising results of {sup 131}I treatment in terms of thyroid size reduction. This review outlines the different treatment modalities on non-toxic nodular goitre with special emphasis on {sup 131}I treatment. By the term nodular goitre the authors include glands with solitary or multiple thyroid nodules with uptake on a scintiscan. At what point of the natural history of non-toxic multinodular goitre {sup 131}I therapy should be used is not clear. In principle, the best result is obtained in smaller goitres and it is possible that the best effect of {sup 131}I is seen if treatment is given to patients with diffuse goitre before these become nodular. However, then there is a potential risk to swing in the direction to where {sup 131}I is used in an indiscriminate way, since the prevalence of non-toxic multinodular goitre is much higher than that of hyperthyroidism. Although we have data on the long-term hazards of {sup 131}I treatment in hyperthyroidism in terms of risk of cancer, we have only follow-up periods of 5 to 10 years for non-toxic goitres in small groups of patients and no data regarding the long-term risk of high-dose {sup 131}I treatment (>600 MBq) for this condition. Ideally, long term randomized studies comparing the effect, side effect and cost-benefit of surgery as opposed to {sup 131}I treatment should be performed. Awaiting this, it is at present mandatory that each individual patient be given a choice of treatment after proper information. 44 refs.

  2. Development of stable isotope dilution assays for the quantitation of Amadori compounds in foods.

    Science.gov (United States)

    Meitinger, Michael; Hartmann, Sandra; Schieberle, Peter

    2014-06-04

    During thermal processing of foods, reducing carbohydrates and amino acids may form 1-amino-1-desoxyketoses named Amadori rearrangement products after the Italian chemist Mario Amadori. Although these compounds are transient intermediates of the Maillard reaction, they are often used as suitable markers to measure the extent of a thermal food processing, such as for spray-dried milk or dried fruits. Several methods are already available in the literature for their quantitation, but measurements are often done with external calibration without addressing losses during the workup procedure. To cope with this challenge, stable isotope dilution assays in combination with LC-MS/MS were developed for the glucose-derived Amadori products of the seven amino acids valine, leucine, isoleucine, phenylalanine, tyrosine, methionine, and histidine using the respective synthesized [(13)C6]-labeled isotopologues as internal standards. The quantitation of the analytes added to a model matrix showed a very good sensitivity with the lowest limits of detection for the Amadori compound of phenylalanine of 0.1 μg/kg starch and 0.2 μg/kg oil, respectively. Also, the standard deviation measured in, for example, wheat beer was only ±2% for this analyte. Application of the method to several foods showed the highest concentrations of the Amadori product of valine in unroasted cocoa (342 mg/kg) as well as in dried bell pepper (3460 mg/kg). In agreement with literature data, drying of foods led to the formation of Amadori products, whereas they were degraded during roasting of, for example, coffee or cocoa. The study presents for the first time results on concentrations of the Amadori compounds of tyrosine and histidine in foods.

  3. Phenolic profile and antioxidant activity from non-toxic Mexican Jatropha curcas L. shell methanolic extracts.

    Science.gov (United States)

    Perea-Domínguez, Xiomara Patricia; Espinosa-Alonso, Laura Gabriela; Hosseinian, Farah; HadiNezhad, Mehri; Valdez-Morales, Maribel; Medina-Godoy, Sergio

    2017-03-01

    Jatropha curcas seed shells are the by-product obtained during oil extraction process. Recently, its chemical composition has gained attention since its potential applications. The aim of this study was to identify phenolic compounds profile from a non-toxic J. curcas shell from Mexico, besides, evaluate J. curcas shell methanolic extract (JcSME) antioxidant activity. Free, conjugate and bound phenolics were fractionated and quantified (606.7, 193.32 and 909.59 μg/g shell, respectively) and 13 individual phenolic compounds were detected by HPLC. The radical-scavenging activity of JcSME was similar to Trolox and ascorbic acid by DPPH assay while by ABTS assay it was similar to BHT. Effective antioxidant capacity by ORAC was found (426.44 ± 53.39 μmol Trolox equivalents/g shell). The Mexican non-toxic J. curcas shell is rich in phenolic compounds with high antioxidant activity; hence, it could be considerate as a good source of natural antioxidants.

  4. Non-Toxic Orbital Maneuvering System Engine Development

    Science.gov (United States)

    Green, Christopher; Claflin, Scott; Maeding, Chris; Butas, John

    1999-01-01

    Recent results using the Aestus engine operated with LOx/ethanol propellant are presented. An experimental program at Rocketdyne Propulsion and Power is underway to adapt this engine for the Boeing Reusable Space Systems Division non-toxic Orbital Maneuvering System/Reaction control System (OMS/RCS) system. Daimler-Chrysler Aerospace designed the Aestus as an nitrogen tetroxide/monomethyl hydrazine (NTO/MMH) upper-stage engine for the Ariane 5. The non-toxic OMS/RCS system's preliminary design requires a LOx/ethanol (O2/C2H5OH) engine that operates with a mixture ratio of 1.8, a specific impulse of 323 seconds, and fits within the original OMS design envelope. This paper describes current efforts to meet these requirements including, investigating engine performance using LOx/ethanol, developing the en-ine system sizing package, and meeting the vehicle operation parameters. Data from hot-fire testing are also presented and discussed.

  5. Radioiodine therapy in non-toxic multinodular goitre

    International Nuclear Information System (INIS)

    Miah, S.R.; Rahman, H.

    2007-01-01

    Full text: The effect of radioiodine in the treatment of non-toxic multinodular goitre has not been adequately evaluated. The aim of the study was to see the effect of radioiodine on thyroid size and function in patients with non-toxic multinodular goitre. We prospectively studied 55 non-toxic multinodular goitre patients treated with radioiodine of which 15 were males and 40 were females with age ranged from 25 years to 60 years (mean ± SD 40.45 ± 10.70 years) for a minimum of 12 months. Patients who were selected were those with local compression symptoms or for cosmetic reasons and the treatment was chosen because of a high operative risk or refusal to be operated on. Thyroid volume and T3, T4, TSH of all patients were determined before treatment and 6 months interval after treatment. Radioiodine was given in the dose ranged from 333 MBq (9 mCi) to 555 MBq (15 mCi) (mean ± SD 11.45 ± 2.04 mCi). The mean thyroid volume was reduced from 44.75 ± 37.44 ml to 28.76 ± 27.25 ml at 12 months (p < 0.001) i.e., reduced by 35.73%. Thyroid volume reduction at 6 months was 21.07%. Hypothyroidism occurred in 9.1% of the patients at 12 months. Side effects were few. Three cases developed radiation thyroiditis and two cases developed hyperthyroidism that was managed conservatively. It has been concluded that radioiodine is effective and well tolerated in the treatment of non-toxic multinodular goitre and may be the treatment of choice in elderly patients, in patients in whom surgery is contraindicated and in patients who are unwilling to undergo surgery. (author)

  6. Microbial degradation of alpha-cypermethrin in soil by compound-specific stable isotope analysis

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Zemin [MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China); Shen, Xiaoli [MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China); Department of Environmental Engineering, Quzhou University, Quzhou 324000 (China); Zhang, Xi-Chang [Laboratory for Teaching in Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China); Liu, Weiping [MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China); Yang, Fangxing, E-mail: fxyang@zju.edu.cn [MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China); Department of Effect-Directed Analysis, Helmholtz Center for Environmental Research – UFZ, Leipzig 04318 (Germany)

    2015-09-15

    Highlights: • Alpha-cypermethrin (α-CP) can be degraded by microorganisms in soil. • Biodegradation of α-CP resulted in carbon isotope fractionation. • A relationship was found between carbon isotope ratios and concentrations of α-CP. • An enrichment factor ϵ of α-CP was determined as −1.87‰. • CSIA is applicable to assess biodegradation of α-CP. - Abstract: To assess microbial degradation of alpha-cypermethrin in soil, attenuation of alpha-cypermethrin was investigated by compound-specific stable isotope analysis. The variations of the residual concentrations and stable carbon isotope ratios of alpha-cypermethrin were detected in unsterilized and sterilized soils spiked with alpha-cypermethrin. After an 80 days’ incubation, the concentrations of alpha-cypermethrin decreased to 0.47 and 3.41 mg/kg in the unsterilized soils spiked with 2 and 10 mg/kg, while those decreased to 1.43 and 6.61 mg/kg in the sterilized soils. Meanwhile, the carbon isotope ratios shifted to −29.14 ± 0.22‰ and −29.86 ± 0.33‰ in the unsterilized soils spiked with 2 and 10 mg/kg, respectively. The results revealed that microbial degradation contributed to the attenuation of alpha-cypermethrin and induced the carbon isotope fractionation. In order to quantitatively assess microbial degradation, a relationship between carbon isotope ratios and residual concentrations of alpha-cypermethrin was established according to Rayleigh equation. An enrichment factor, ϵ = −1.87‰ was obtained, which can be employed to assess microbial degradation of alpha-cypermethrin. The significant carbon isotope fractionation during microbial degradation suggests that CSIA is a proper approach to qualitatively detect and quantitatively assess the biodegradation during attenuation process of alpha-cypermethrin in the field.

  7. Radioactive and stable metal bioaccumulation, crystalline compound and siderophore detection in Clavariadelphus truncatus

    International Nuclear Information System (INIS)

    Gaso, M.I.; Segovia, N.; Morton, O.; Lopez, J.L.; Machuca, A.; Hernandez, E.

    2007-01-01

    137 Cs and 40 K activity concentrations and stable elements have been measured in Clavariadelphus truncatus collected in Mexico. Iron-chelating compounds of siderophore-type was also studied in the species. 137 Cs and 40 K were determined in soil and mushroom samples with HpGe gamma-ray spectrometry. Macro- and micro-elemental concentrations were determined by XRF and ICP-MS. Siderophore detection was obtained with a colorimetric assay and X-ray diffraction analysis was performed using a Siemens D5000 diffractometer. 137 Cs geometric mean concentration in C. truncatus was 26 times higher as compared with other Mexican edible mushroom species, while 40 K showed stability. Soil-C. truncatus concentration ratio for 137 Cs and other micro-elements such as Cs, Rb and Pb were also higher than other Mexican edible species. The 137 Cs committed effective dose due to the ingestion of C. truncatus was 8 x 10 -6 Sv year -1 . The main crystalline structure found in C. truncatus was D-Mannitol

  8. Radioactive and stable metal bioaccumulation, crystalline compound and siderophore detection in Clavariadelphus truncatus

    Energy Technology Data Exchange (ETDEWEB)

    Gaso, M.I. [ININ, Ap. Post. 18-1027, C.P. 11801, Mexico D.F. (Mexico)], E-mail: migp@nuclear.inin.mx; Segovia, N. [Instituto de Geofisica, UNAM, Ciudad Universitaria, 04510 Mexico, D.F. (Mexico)], E-mail: nurina@terra.com.mx; Morton, O. [Instituto de Geofisica, UNAM, Ciudad Universitaria, 04510 Mexico, D.F. (Mexico)], E-mail: omorton@geofisica.unam.mx; Lopez, J.L. [Instituto de Geografia, UNAM, Ciudad Universitaria, 04510 Mexico, D.F. (Mexico)], E-mail: jlc@servidor.unam.mx; Machuca, A. [Departmento Forestal, Universidad de Concepcion, Los Angeles (Chile)], E-mail: angmachu@udec.cl; Hernandez, E. [Instituto de Geofisica, UNAM, Ciudad Universitaria, 04510 Mexico, D.F. (Mexico)], E-mail: aeliza@geofisica.unam.mx

    2007-09-15

    {sup 137}Cs and {sup 40}K activity concentrations and stable elements have been measured in Clavariadelphus truncatus collected in Mexico. Iron-chelating compounds of siderophore-type was also studied in the species. {sup 137}Cs and {sup 40}K were determined in soil and mushroom samples with HpGe gamma-ray spectrometry. Macro- and micro-elemental concentrations were determined by XRF and ICP-MS. Siderophore detection was obtained with a colorimetric assay and X-ray diffraction analysis was performed using a Siemens D5000 diffractometer. {sup 137}Cs geometric mean concentration in C. truncatus was 26 times higher as compared with other Mexican edible mushroom species, while {sup 40}K showed stability. Soil-C. truncatus concentration ratio for {sup 137}Cs and other micro-elements such as Cs, Rb and Pb were also higher than other Mexican edible species. The {sup 137}Cs committed effective dose due to the ingestion of C. truncatus was 8 x 10{sup -6} Sv year{sup -1}. The main crystalline structure found in C. truncatus was D-Mannitol.

  9. Stable isotope applications in biomolecular structure and mechanisms. A meeting to bring together producers and users of stable-isotope-labeled compounds to assess current and future needs

    International Nuclear Information System (INIS)

    Trewhella, J.; Cross, T.A.; Unkefer, C.J.

    1994-12-01

    Knowledge of biomolecular structure is a prerequisite for understanding biomolecular function, and stable isotopes play an increasingly important role in structure determination of biological molecules. The first Conference on Stable Isotope Applications in Biomolecular Structure and Mechanisms was held in Santa Fe, New Mexico, March 27--31, 1994. More than 120 participants from 8 countries and 44 institutions reviewed significant developments, discussed the most promising applications for stable isotopes, and addressed future needs and challenges. Participants focused on applications of stable isotopes for studies of the structure and function of proteins, peptides, RNA, and DNA. Recent advances in NMR techniques neutron scattering, EPR, and vibrational spectroscopy were highlighted in addition to the production and synthesis of labeled compounds. This volume includes invited speaker and poster presentations as well as a set of reports from discussion panels that focused on the needs of the scientific community and the potential roles of private industry, the National Stable Isotope Resource, and the National High Magnetic Field Laboratory in serving those needs. This is the leading abstract. Individual papers are processed separately for the database

  10. Stable isotope applications in biomolecular structure and mechanisms. A meeting to bring together producers and users of stable-isotope-labeled compounds to assess current and future needs

    Energy Technology Data Exchange (ETDEWEB)

    Trewhella, J.; Cross, T.A.; Unkefer, C.J. [eds.

    1994-12-01

    Knowledge of biomolecular structure is a prerequisite for understanding biomolecular function, and stable isotopes play an increasingly important role in structure determination of biological molecules. The first Conference on Stable Isotope Applications in Biomolecular Structure and Mechanisms was held in Santa Fe, New Mexico, March 27--31, 1994. More than 120 participants from 8 countries and 44 institutions reviewed significant developments, discussed the most promising applications for stable isotopes, and addressed future needs and challenges. Participants focused on applications of stable isotopes for studies of the structure and function of proteins, peptides, RNA, and DNA. Recent advances in NMR techniques neutron scattering, EPR, and vibrational spectroscopy were highlighted in addition to the production and synthesis of labeled compounds. This volume includes invited speaker and poster presentations as well as a set of reports from discussion panels that focused on the needs of the scientific community and the potential roles of private industry, the National Stable Isotope Resource, and the National High Magnetic Field Laboratory in serving those needs. This is the leading abstract. Individual papers are processed separately for the database.

  11. Heterocyclic Schiff bases as non toxic antioxidants: Solvent effect, structure activity relationship and mechanism of action

    Science.gov (United States)

    Shanty, Angamaly Antony; Mohanan, Puzhavoorparambil Velayudhan

    2018-03-01

    Phenolic heterocyclic imine based Schiff bases from Thiophene-2-carboxaldehyde and Pyrrole-2-carboxaldehyde were synthesized and characterized as novel antioxidants. The solvent effects of these Schiff bases were determined and compared with standard antioxidants, BHA employing DPPH assay and ABTS assay. Fixed reaction time and Steady state measurement were used for study. IC50 and EC50 were calculated. Structure-activity relationship revealed that the electron donating group in the phenolic ring increases the activity where as the electron withdrawing moiety decreases the activity. The Schiff base derivatives showed antioxidant property by two different pathways namely SPLET and HAT mechanisms in DPPH assay. While in ABTS method, the reaction between ABTS radical and Schiff bases involves electron transfer followed by proton transfer (ET-PT) mechanism. The cytotoxicity of these compounds has been evaluated by MTT assay. The results showed that all these compounds are non toxic in nature.

  12. A Novel Non-Toxic Xylene Substitute (SBO) for Histology

    OpenAIRE

    Kunhua, Wang; Chuming, Fan; Tao, Lai; Yanmei, Yang; Xin, Yang; Xiaoming, Zhang; Xuezhong, Guo; Xun, Lai

    2011-01-01

    Xylene has been generally used as a clearing and deparaffinizing agent in histology. Because of the potential toxic and flammable nature of xylene, its substitutes have been introduced into some laboratories. In this study, we introduced a novel, non-toxic xylene substitute (SBO), which was generated through a mixture of 86% of white oil No.2 and 14% of N-heptane. SBO had a high boiling point (188°C) and flash point (144°C) coupled with a scentless and decreased volatility. To compare the eff...

  13. An analytical system for the measurement of stable hydrogen isotopes in ambient volatile organic compounds

    Science.gov (United States)

    Meisehen, T.; Bühler, F.; Koppmann, R.; Krebsbach, M.

    2015-10-01

    Stable isotope measurements in atmospheric volatile organic compounds (VOCs) are an excellent tool to analyse chemical and dynamical processes in the atmosphere. While up to now isotope studies of VOCs in ambient air have mainly focussed on carbon isotopes, we herein present a new measurement system to investigate hydrogen isotope ratios in atmospheric VOCs. This system, consisting of a gas chromatography pyrolysis isotope ratio mass spectrometer (GC-P-IRMS) and a pre-concentration system, was thoroughly characterised using a VOC test mixture. A precision of better than 9 ‰ (in δ 2H) is achieved for n-pentane, 2-methyl-1,3-butadiene (isoprene), n-heptane, 4-methyl-pentane-2-one (4-methyl-2-pentanone), methylbenzene (toluene), n-octane, ethylbenzene, m/p-xylene and 1,2,4-trimethylbenzene. A comparison with independent measurements via elemental analysis shows an accuracy of better than 9 ‰ for n-pentane, n-heptane, 4-methyl-2-pentanone, toluene and n-octane. Above a minimum required pre-concentrated compound mass the obtained δ 2H values are constant within the standard deviations. In addition, a remarkable influence of the pyrolysis process on the isotope ratios is found and discussed. Reliable measurements are only possible if the ceramic tube used for the pyrolysis is sufficiently conditioned, i.e. the inner surface is covered with a carbon layer. It is essential to verify this conditioning regularly and to renew it if required. Furthermore, influences of a necessary H3+ correction and the pyrolysis temperature on the isotope ratios are discussed. Finally, the applicability to measure hydrogen isotope ratios in VOCs at ambient levels is demonstrated with measurements of outside air on 5 different days in February and March 2015. The measured hydrogen isotope ratios range from -136 to -105 ‰ forn-pentane, from -86 to -63 ‰ for toluene, from -39 to -15 ‰ for ethylbenzene, from -99 to -68 ‰ for m/p-xylene and from -45 to -34 ‰ for o-xylene.

  14. AMAP, the alleged non-toxic isomer of acetaminophen, is toxic in rat and human liver

    NARCIS (Netherlands)

    Hadi, M; Dragovic, S.; van Swelm, R; Herpers, B; van de Water, B.; Russel, RG; Commandeur, J.N.M.; Groothuis, G.M.

    2013-01-01

    N-acetyl-meta-aminophenol (AMAP) is generally considered as a non-toxic regioisomer of the wellknown hepatotoxicant acetaminophen (APAP). However, so far, AMAP has only been shown to be non-toxic in mice and hamsters. To investigate whether AMAP could also be used as non-toxic analog of APAP in rat

  15. AMAP, the alleged non-toxic isomer of acetaminophen, is toxic in rat and human liver

    NARCIS (Netherlands)

    Hadi, Mackenzie; Dragovic, Sanja; van Swelm, Rachel; Herpers, Bram; van de Water, Bob; Russel, Frans G. M.; Commandeur, Jan N. M.; Groothuis, Geny M. M.

    N-acetyl-meta-aminophenol (AMAP) is generally considered as a non-toxic regioisomer of the well-known hepatotoxicant acetaminophen (APAP). However, so far, AMAP has only been shown to be non-toxic in mice and hamsters. To investigate whether AMAP could also be used as non-toxic analog of APAP in rat

  16. Tracing carbon flow through coral reef food webs using a compound-specific stable isotope approach.

    Science.gov (United States)

    McMahon, Kelton W; Thorrold, Simon R; Houghton, Leah A; Berumen, Michael L

    2016-03-01

    Coral reefs support spectacularly productive and diverse communities in tropical and sub-tropical waters throughout the world's oceans. Debate continues, however, on the degree to which reef biomass is supported by new water column production, benthic primary production, and recycled detrital carbon (C). We coupled compound-specific stable C isotope ratio (δ(13)C) analyses with Bayesian mixing models to quantify C flow from primary producers to coral reef fishes across multiple feeding guilds and trophic positions in the Red Sea. Analyses of reef fishes with putative diets composed primarily of zooplankton (Amblyglyphidodon indicus), benthic macroalgae (Stegastes nigricans), reef-associated detritus (Ctenochaetus striatus), and coral tissue (Chaetodon trifascialis) confirmed that δ(13)C values of essential amino acids from all baseline C sources were both isotopically diagnostic and accurately recorded in consumer tissues. While all four source end-members contributed to the production of coral reef fishes in our study, a single-source end-member often dominated dietary C assimilation of a given species, even for highly mobile, generalist top predators. Microbially reworked detritus was an important secondary C source for most species. Seascape configuration played an important role in structuring resource utilization patterns. For instance, Lutjanus ehrenbergii showed a significant shift from a benthic macroalgal food web on shelf reefs (71 ± 13 % of dietary C) to a phytoplankton-based food web (72 ± 11 %) on oceanic reefs. Our work provides insights into the roles that diverse C sources play in the structure and function of coral reef ecosystems and illustrates a powerful fingerprinting method to develop and test nutritional frameworks for understanding resource utilization.

  17. Assessing the functional diversity of herbivorous reef fishes using a compound-specific stable isotope approach

    KAUST Repository

    Tietbohl, Matthew

    2016-12-01

    Herbivorous coral reef fishes play an important role in helping to structure their environment directly by consuming algae and indirectly by promoting coral health and growth. These fishes are generally separated into three broad groups: browsers, grazers, and excavators/scrapers, with these groupings often thought to have a fixed general function and all fishes within a group thought to have similar ecological roles. This categorization assumes a high level of functional redundancy within herbivorous fishes. However, recent evidence questions the use of this broad classification scheme, and posits that there may actually be more resource partitioning within these functional groupings. Here, I use a compound-specific stable isotope approach (CSIA) to show there appears to be a greater diversity of functional roles than previously assumed within broad functional groups. The δ13C signatures from essential amino acids of reef end-members (coral, macroalgae, detritus, and phytoplankton) and fish muscle were analyzed to investigate differences in resource use between fishes. Most end-members displayed clear isotopic differences, and most fishes within functional groups were dissimilar in their isotopic signature, implying differences in the resources they target. No grazers closely resembled each other isotopically, implying a much lower level of functional redundancy within this group; scraping parrotfish were also distinct from excavating parrotfish and to a lesser degree distinct between scrapers. This study highlights the potential of CSIA to help distinguish fine-scale ecological differences within other groups of reef organisms as well. These results question the utility of lumping nominally herbivorous fishes into broad groups with assumed similar roles. Given the apparent functional differences between nominally herbivorous reef fishes, it is important for managers to incorporate the diversity of functional roles these fish play.

  18. Assessing the functional diversity of herbivorous reef fishes using a compound-specific stable isotope approach

    KAUST Repository

    Tietbohl, Matthew

    2016-01-01

    Herbivorous coral reef fishes play an important role in helping to structure their environment directly by consuming algae and indirectly by promoting coral health and growth. These fishes are generally separated into three broad groups: browsers, grazers, and excavators/scrapers, with these groupings often thought to have a fixed general function and all fishes within a group thought to have similar ecological roles. This categorization assumes a high level of functional redundancy within herbivorous fishes. However, recent evidence questions the use of this broad classification scheme, and posits that there may actually be more resource partitioning within these functional groupings. Here, I use a compound-specific stable isotope approach (CSIA) to show there appears to be a greater diversity of functional roles than previously assumed within broad functional groups. The δ13C signatures from essential amino acids of reef end-members (coral, macroalgae, detritus, and phytoplankton) and fish muscle were analyzed to investigate differences in resource use between fishes. Most end-members displayed clear isotopic differences, and most fishes within functional groups were dissimilar in their isotopic signature, implying differences in the resources they target. No grazers closely resembled each other isotopically, implying a much lower level of functional redundancy within this group; scraping parrotfish were also distinct from excavating parrotfish and to a lesser degree distinct between scrapers. This study highlights the potential of CSIA to help distinguish fine-scale ecological differences within other groups of reef organisms as well. These results question the utility of lumping nominally herbivorous fishes into broad groups with assumed similar roles. Given the apparent functional differences between nominally herbivorous reef fishes, it is important for managers to incorporate the diversity of functional roles these fish play.

  19. Exploration of stable compounds, crystal structures, and superconductivity in the Be-H system

    Directory of Open Access Journals (Sweden)

    Shuyin Yu

    2014-10-01

    Full Text Available Using first-principles variable-composition evolutionary methodology, we explored the high-pressure structures of beryllium hydrides between 0 and 400 GPa. We found that BeH2 remains the only stable compound in this pressure range. The pressure-induced transformations are predicted as I b a m → P 3 ̄ m 1 → R 3 ̄ m → C m c m → P 4 / n m m , which occur at 24, 139, 204 and 349 GPa, respectively. P 3 ̄ m 1 and R 3 ̄ m structures are layered polytypes based on close packings of H atoms with Be atoms filling all octahedral voids in alternating layers. Cmcm and P4/nmm contain two-dimensional triangular networks with each layer forming a kinked slab in the ab-plane. P 3 ̄ m 1 and R 3 ̄ m are semiconductors while Cmcm and P4/nmm are metallic. We have explored superconductivity of both metal phases, and found large electron-phonon coupling parameters of λ = 0.63 for Cmcm with a Tc of 32.1-44.1 K at 250 GPa and λ = 0.65 for P4/nmm with a Tc of 46.1-62.4 K at 400 GPa. The dependence of Tc on pressure indicates that Tc initially increases to a maximum of 45.1 K for Cmcm at 275 GPa and 97.0 K for P4/nmm at 365 GPa, and then decreases with increasing pressure for both phases.

  20. Tracing carbon flow through coral reef food webs using a compound-specific stable isotope approach

    KAUST Repository

    McMahon, Kelton

    2015-11-21

    Coral reefs support spectacularly productive and diverse communities in tropical and sub-tropical waters throughout the world’s oceans. Debate continues, however, on the degree to which reef biomass is supported by new water column production, benthic primary production, and recycled detrital carbon (C). We coupled compound-specific stable C isotope ratio (δ13C) analyses with Bayesian mixing models to quantify C flow from primary producers to coral reef fishes across multiple feeding guilds and trophic positions in the Red Sea. Analyses of reef fishes with putative diets composed primarily of zooplankton (Amblyglyphidodon indicus), benthic macroalgae (Stegastes nigricans), reef-associated detritus (Ctenochaetus striatus), and coral tissue (Chaetodon trifascialis) confirmed that δ13C values of essential amino acids from all baseline C sources were both isotopically diagnostic and accurately recorded in consumer tissues. While all four source end-members contributed to the production of coral reef fishes in our study, a single-source end-member often dominated dietary C assimilation of a given species, even for highly mobile, generalist top predators. Microbially reworked detritus was an important secondary C source for most species. Seascape configuration played an important role in structuring resource utilization patterns. For instance, Lutjanus ehrenbergii showed a significant shift from a benthic macroalgal food web on shelf reefs (71 ± 13 % of dietary C) to a phytoplankton-based food web (72 ± 11 %) on oceanic reefs. Our work provides insights into the roles that diverse C sources play in the structure and function of coral reef ecosystems and illustrates a powerful fingerprinting method to develop and test nutritional frameworks for understanding resource utilization.

  1. Oleuropein, a non-toxic olive iridoid, is an anti-tumor agent and cytoskeleton disruptor

    International Nuclear Information System (INIS)

    Hamdi, Hamdi K.; Castellon, Raquel

    2005-01-01

    Oleuropein, a non-toxic secoiridoid derived from the olive tree, is a powerful antioxidant and anti-angiogenic agent. Here, we show it to be a potent anti-cancer compound, directly disrupting actin filaments in cells and in a cell-free assay. Oleuropein inhibited the proliferation and migration of advanced-grade tumor cell lines in a dose-responsive manner. In a novel tube-disruption assay, Oleuropein irreversibly rounded cancer cells, preventing their replication, motility, and invasiveness; these effects were reversible in normal cells. When administered orally to mice that developed spontaneous tumors, Oleuropein completely regressed tumors in 9-12 days. When tumors were resected prior to complete regression, they lacked cohesiveness and had a crumbly consistency. No viable cells could be recovered from these tumors. These observations elevate Oleuropein from a non-toxic antioxidant into a potent anti-tumor agent with direct effects against tumor cells. Our data may also explain the cancer-protective effects of the olive-rich Mediterranean diet

  2. Advisory group meeting on stable isotope labelled compounds in biomedical studies

    International Nuclear Information System (INIS)

    Vera Ruiz, H.; Parr, R.M.

    1985-11-01

    The programme of the meeting was restricted to topics involving applications of stable isotopes of the lighter elements (H, C, N, O). The current status of stable isotope techniques and applications in nutritional and biomedical studies, the applicability of these techniques in developing countries and the IAEA's future programmes on this topic were discussed

  3. Demonstration of a Non-Toxic Reaction Control Engine

    Science.gov (United States)

    Robinson, Philip J.; Turpin, Alicia A.; Veith, Eric M.

    2007-01-01

    T:hree non-toxic demonstration reaction control engines (RCE) were successfully tested at the Aerojet Sacramento facility under a technology contract sponsored by the National Aeronautics and Space Administration's (NASA) Marshall Space Flight Center (MSFC). The goals of the NASA MSFC contract (NAS8-01109) were to develop and expand the technical maturity of a non-toxic, on-orbit auxiliary propulsion system (APS) thruster under the auspices of the Exploration Systems Mission Directorate. The demonstration engine utilized Liquid Oxygen (LOX) and Ethanol as propellants to produce 870 lbf thrust. The Aerojet RCE's were successfully acceptance tested over a broad range of operating conditions. Steady state tests evaluated engine response to varying chamber pressures and mixture ratios. In addition to the steady state tests, a variety of pulsing tests were conducted over a wide range of electrical pulse widths (EPW). Each EPW condition was also tested over a range of percent duty cycles (DC), and bit impulse and pulsing specific impulse were determined for each of these conditions. Subsequent to acceptance testing at Aerojet, these three engines were delivered to the NASA White Sands Test Facility (WSTF) in April 2005 for incorporation into a cryogenic Auxiliary Propulsion System Test Bed (APSTB). The APSTB is a test article that will be utilized in an altitude test cell to simulate anticipated mission applications. The objectives of this APSTB testing included evaluation of engine performance over an extended duty cycle map of propellant pressure and temperature, as well as engine and system performance at typical mission duty cycles over extended periods of time. This paper provides acceptance test results and a status of the engine performance as part of the system level testing.

  4. SYNTHESIS, THERMAL STUDIES AND CONVERSION DEGREE OF DIMETHACRYLATE POLYMERS USING NEW NON-TOXIC COINITIATORS

    Directory of Open Access Journals (Sweden)

    Rafael Turra Alarcon

    Full Text Available The aim of this paper is to replace toxic coinitiators (tertiary amines by non-toxic compounds such as glycerol and inositol (polyalcohol in dimethacrylate resins. For this purpose, mid infrared spectroscopy (MIR was used to calculate the monomers' degree of conversion (%DC; as well as simultaneous Thermogravimetric Analysis – Differential Thermal Analysis (TGA-DTA and Differential Scanning Calorimetry (DSC were conducted to evaluate thermal stability, degradation steps, and thermal events. The use of different initiator systems did not modify the thermal events or the thermal stability of each of the dimethacrylate resins. Results show a substitution of system 2 (toxicity by system 3 (low toxicity, which had a good conversion velocity and total conversion in some monomers, is plausible.

  5. Challenges for the Development of New Non-Toxic Antifouling Solutions

    Directory of Open Access Journals (Sweden)

    Jean-Philippe Maréchal

    2009-10-01

    Full Text Available Marine biofouling is of major economic concern to all marine industries. The shipping trade is particularly alert to the development of new antifouling (AF strategies, especially green AF paint as international regulations regarding the environmental impact of the compounds actually incorporated into the formulations are becoming more and more strict. It is also recognised that vessels play an extensive role in invasive species propagation as ballast waters transport potentially threatening larvae. It is then crucial to develop new AF solutions combining advances in marine chemistry and topography, in addition to a knowledge of marine biofoulers, with respect to the marine environment. This review presents the recent research progress made in the field of new non-toxic AF solutions (new microtexturing of surfaces, foul-release coatings, and with a special emphasis on marine natural antifoulants as well as the perspectives for future research directions.

  6. Efficient free energy calculations for compounds with multiple stable conformations separated by high energy barriers

    NARCIS (Netherlands)

    Hritz, J.; Oostenbrink, C.

    2009-01-01

    Compounds with high intramolecular energy barriers represent challenging targets for free energy calculations because of the difficulty to obtain sufficient conformational sampling. Existing approaches are therefore computationally very demanding, thus preventing practical applications for such

  7. Development of Inexpensive, Efficient and Non-Toxic Thermoelectric Materials

    Science.gov (United States)

    Gali, Anand Pratik

    In the wake of the impending climate change challenges, it is highly necessary to reevaluate our energy utilization technologies and ensure their efficient operation. Fossil fuel powered power-plants account for the majority of the energy production in the United States. With an average efficiency not exceeding 40%, these fossil fuel power plants dissipate exorbitant amounts of wasted heat. One of the ways of making such energy conversion processes more efficient is by incorporating technologies that can harvest this scavenge heat. One of the ways of achieving this is by the use of thermoelectric (TE) materials, which utilize the Seebeck effect to convert thermal gradient into potential difference. Therefore, our research project focusses on development of TE materials, which are inexpensive, efficient, and non-toxic. Fe0.50V0.25Al0.25 is a narrow band-gap semiconductor, ideal for TE applications. Unlike the current market leader Bi0.4Te0.6, Fe0.50V0.25 Al0.25 contains earth abundant and non-toxic constituents making it viable for commercial production. Nevertheless, the TE efficiency, ZT, of Fe0.50V0.25Al0.25 is limited by its high thermal conductivity. Therefore, the goal of the current research is two-fold. Firstly, to design and fabricate apparatus for performing TE characterization on bulk materials. For this purpose, two sets of apparatus were designed and fabricated for measuring high temperature Seebeck coefficient and electrical resistivity. Secondly, to study the influence of doping on TE properties of Fe0.50V0.25Al0.25 alloy. In order to achieve this, vanadium in Fe0.50V0.25Al0.25 was substituted with dopants like Ti, Cr, Zr, W, Nb, Ta. This led to a 20 times improvement in ZT, from the baseline Fe0.50V0.25Al0.25, by effectively reducing the thermal conductivity and increasing the Seebeck coefficient.

  8. Non toxic additives for improved fabric filter performance

    Energy Technology Data Exchange (ETDEWEB)

    Bustard, C.J.; Baldrey, K.E.; Ebner, T.G. [ADA Technologies, Inc., Englewood, CO (United States)] [and others

    1995-11-01

    The overall objective of this three-phase Small Business innovative Research (SBIR) program funded by the Department of Energy pittsburgh Energy Technology Center (PETC) is to commercialize a technology based upon the use of non-toxic, novel flue gas conditioning agents to improve particulate air toxic control and overall fabric filter performance. The ultimate objective of the Phase II program currently in progress is to demonstrate that the candidate additives are successful at full-scale on flue gas from a coal-fired utility boiler. This paper covers bench-scale field tests conducted during the period February through May, 1995. The bench-scale additives testing was conducted on a flue gas slipstream taken upstream of the existing particulate control device at a utility power plant firing a Texas lignite coal. These tests were preceded by extensive testing with additives in the laboratory using a simulated flue gas stream and re-dispersed flyash from the same power plant. The bench-scale field testing was undertaken to demonstrate the performance with actual flue gas of the bet candidate additives previously identified in the laboratory. Results from the bench-scale tests will be used to establish operating parameters for a larger-scale demonstration on either a single baghouse compartment or a full baghouse at the same site.

  9. A novel non-toxic xylene substitute (SBO) for histology.

    Science.gov (United States)

    Kunhua, Wang; Chuming, Fan; Tao, Lai; Yanmei, Yang; Xin, Yang; Xiaoming, Zhang; Xuezhong, Guo; Xun, Lai

    2012-01-01

    Xylene has been generally used as a clearing and deparaffinizing agent in histology. Because of the potential toxic and flammable nature of xylene, its substitutes have been introduced into some laboratories. In this study, we introduced a novel, non-toxic xylene substitute (SBO), which was generated through a mixture of 86% of white oil No.2 and 14% of N-heptane. SBO had a high boiling point (188°C) and flash point (144°C) coupled with a scentless and decreased volatility. To compare the effectiveness of SBO and xylene in histology, a wide range of tissue samples from rats and human beings were processed in parallel in SBO and xylene, subjected to various staining procedures. Similar to the xylene-processed paraffin blocks, the SBO-processed counterparts were easy to section without any evidence of cell shrinkage. Assessment of the SBO-treated sections stained with hematoxylin-eosin revealed a good maintenance of cell morphology and structure, and a clear definition of the cytoplasm and the nucleus. Moreover, comparable good results were achieved between the SBO- and xylene-processed tissues in other histochemical and immunohistochemical stainings. Six-month clinical applications at one department of pathology supported the potentials of SBO as a xylene substitute. In conclusion, we suggest that SBO is a safe and efficient substitute of xylene and may probably replace xylene without losing valuable diagnostic information.

  10. Behavior of radon, chemical compounds and stable elements in underground water

    International Nuclear Information System (INIS)

    Lopez R, N.; Segovia, N.; Lopez, M.B.E.; Pena, P.; Armienta, M.A.; Godinez, L.; Seidel, J.L.

    2001-01-01

    The radon behavior, chemical compounds, major and trace elements in water samples of four springs and three wells of urban and agricultural zones around the Jocotitlan volcano and El Oro region was determined, both of them located in the medium part of the Mexican neo-volcanic axis. The 222 Rn was measured by the liquid scintillation method, the analysis of major components was realized with conventional chemical techniques, while the trace elements were quantified using an Icp-Ms. The average values of the radon concentrations obtained during one year were constant relatively, in an interval from 0.97 to 4.99 Bq/lt indicating a fast transport from the reload area toward the sampling points. the compounds, major and trace elements showed differences which indicate distinct origins of water from the site studies. (Author)

  11. Authenticity of aroma components Enantiomeric separation and compound specific stable isotope analysis

    DEFF Research Database (Denmark)

    Hansen, Anne-Mette Sølvbjerg

    of both enantiomers contrary to natural aromas where often only one of the enantiomers will be in excess. Consequently, if equal amounts of enantiomers are detected in a food product labelled “Natural” it could be an indication of adulteration. Artificial aroma compounds often have very different ratios......The word “authenticity” is increasingly used in the marketing of food products. A product can be marketed claiming its authenticity such as containing only natural ingredients or originating from a special location produced using local traditional production methods. Within the area of food...... ingredients a problem with authenticity of aroma compounds has occurred, because natural aromas are wholly or partly replaced with synthetic ones. This is a large economic problem, since natural aromas are often more expensive than artificial ones. Furthermore, the European Union has legal requirements...

  12. Charge and spin density in s-stable rare earth intermetallic compounds

    International Nuclear Information System (INIS)

    Graaf, H. de.

    1982-01-01

    This thesis deals with a study of the electronic structure of rare earth intermetallic compounds, in particular the electronic charge and spin density distribution. These are closely related to the properties of the rare earth ions, which carry the partly filled 4f shell. In chapter 1 a survey of the theory of hyperfine interaction as far as it has a bearing on the Moessbauer effect of 155 Gd and 151 Eu is given. Also some details of the Moessbauer spectra, which have practical importance are discussed. In chapter 2 the experimental set-up is described. Special attention is paid to the gamma radiation source and gamma detection requirements. In chapter 3 the author introduces the theoretical framework which will be used to interpret the measurements. In chapter 4 the results of the 155 Gd Moessbauer measurements are presented. Also it is discussed how the result can be understood in terms of the charge and spin density in rare earth intermetallic compounds. In order to lend support to the picture emerging from the previous chapter, in chapter 5 the conduction electron band structure of some representative Gd intermetallics is computed with an approximate semi-empirical LCAO method. The results are compared with those from chapter 4. Finally, in chapter 6, the 151 Eu resonance is used to investigate the temperature dependence of the hyperfine field and line width in the Eu intermetallic compounds Eu 2 Mg 17 and EuMg 5 . (Auth.)

  13. Structural studies on a non-toxic homologue of type II RIPs from ...

    Indian Academy of Sciences (India)

    Structural studies on a non-toxic homologue of type II RIPs from bitter gourd: Molecular basis of non-toxicity, conformational selection and glycan structure. MS accepted http://www.ias.ac.in/jbiosci. THYAGESHWAR CHANDRAN, ALOK SHARMA and M VIJAYAN. J. Biosci. 40(5), October 2015, 929–941, © Indian Academy of ...

  14. Optimizing sample pretreatment for compound-specific stable carbon isotopic analysis of amino sugars in marine sediment

    Science.gov (United States)

    Zhu, R.; Lin, Y.-S.; Lipp, J. S.; Meador, T. B.; Hinrichs, K.-U.

    2014-09-01

    Amino sugars are quantitatively significant constituents of soil and marine sediment, but their sources and turnover in environmental samples remain poorly understood. The stable carbon isotopic composition of amino sugars can provide information on the lifestyles of their source organisms and can be monitored during incubations with labeled substrates to estimate the turnover rates of microbial populations. However, until now, such investigation has been carried out only with soil samples, partly because of the much lower abundance of amino sugars in marine environments. We therefore optimized a procedure for compound-specific isotopic analysis of amino sugars in marine sediment, employing gas chromatography-isotope ratio mass spectrometry. The whole procedure consisted of hydrolysis, neutralization, enrichment, and derivatization of amino sugars. Except for the derivatization step, the protocol introduced negligible isotopic fractionation, and the minimum requirement of amino sugar for isotopic analysis was 20 ng, i.e., equivalent to ~8 ng of amino sugar carbon. Compound-specific stable carbon isotopic analysis of amino sugars obtained from marine sediment extracts indicated that glucosamine and galactosamine were mainly derived from organic detritus, whereas muramic acid showed isotopic imprints from indigenous bacterial activities. The δ13C analysis of amino sugars provides a valuable addition to the biomarker-based characterization of microbial metabolism in the deep marine biosphere, which so far has been lipid oriented and biased towards the detection of archaeal signals.

  15. Source characterization using compound composition and stable carbon isotope ratio of PAHs in sediments from lakes, harbor, and shipping waterway

    International Nuclear Information System (INIS)

    Kim, Moonkoo; Kennicutt, Mahlon C.; Qian, Yaorong

    2008-01-01

    Molecular compositions and compound specific stable carbon isotope ratios of polycyclic aromatic hydrocarbons (PAH) isolated from sediments were used to characterize possible sources of contamination at an urban lake, a harbor, a shipping waterway, and a relatively undisturbed remote lake in the northwest United States. Total PAH concentrations in urban lake sediments ranged from 66.0 to 16,500 μg g -1 dry wt. with an average of 2600 μg g -1 , which is ∼ 50, 100, and 400 times higher on average than PAH in harbor (48 μg g -1 on average), shipping waterway (26 μg g -1 ), and remote lake (7 μg g -1 ) sediments, respectively. The PAH distribution patterns, methyl phenanthrene/phenanthrene ratios, and a pyrogenic index at the sites suggest a pyrogenic origin for PAHs. Source characterization using principal component analysis and various molecular indices including C2-dibenzothiophenes/C2-phenanthrenes, C3-dibenzothiophenes/C3-phenanthrenes, and C2-chrysenes/C2-phenanthrenes ratios, was able to differentiate PAH deposited in sediments from the four sites. The uniqueness of the source of the sediment PAHs from urban lake was also illustrated by compound specific stable carbon isotope analysis. It was concluded that urban lake sediments are accumulating PAH from sources that are unique from contamination detected at nearby sites in the same watershed

  16. Yellow phosphorus process to convert toxic chemicals to non-toxic products

    Science.gov (United States)

    Chang, S.G.

    1994-07-26

    The present invention relates to a process for generating reactive species for destroying toxic chemicals. This process first contacts air or oxygen with aqueous emulsions of molten yellow phosphorus. This contact results in rapid production of abundant reactive species such as O, O[sub 3], PO, PO[sub 2], etc. A gaseous or liquid aqueous solution organic or inorganic chemicals is next contacted by these reactive species to reduce the concentration of toxic chemical and result in a non-toxic product. The final oxidation product of yellow phosphorus is phosphoric acid of a quality which can be recovered for commercial use. A process is developed such that the byproduct, phosphoric acid, is obtained without contamination of toxic species in liquids treated. A gas stream containing ozone without contamination of phosphorus containing species is also obtained in a simple and cost-effective manner. This process is demonstrated to be effective for destroying many types of toxic organic, or inorganic, compounds, including polychlorinated biphenyls (PCB), aromatic chlorides, amines, alcohols, acids, nitro aromatics, aliphatic chlorides, polynuclear aromatic compounds (PAH), dyes, pesticides, sulfides, hydroxyamines, ureas, dithionates and the like. 20 figs.

  17. Radioiodine therapy in non toxic multi nodular goitre, preliminary results

    International Nuclear Information System (INIS)

    Chiti, A.; Travaini, L.L.; Tadayyon, S.; Vannucchi, G.; Fugazzola, L.; Beck-Peccoz, P.

    2002-01-01

    Aim: Aim of our study was to assess the efficacy of 131 I therapy in patients (pts) affected by non toxic multinodular goitre (NTMG). NTMG is a thyroid disease with a high prevalence, especially in low-iodine intake regions. Treatment of NTMG often requires surgery. However, thyroidectomy may be risky in some patients and radioiodine therapy could be an alternative treatment to reduce thyroid volume. We also evaluated if lithium administration can improve the efficacy of radioiodine treatment in this pts. Material and Methods: We enrolled 39 pts (8 males, 31 females; mean age 59 y, range 40-79 y) affected by NTMG. Mean thyroid volume (TV) at ultrasound was of 46.8 ml (range 18.5-87.3). Pts were randomised in 2 groups. Group 1: iodine therapy + lithium therapy 900 mg/die for 6 days; Group 2: iodine therapy alone. We also define 3 clusters of pts by TV. A:15-30 ml; B:31-40 ml; C: > 40 ml. The 131 I activity (MBq) was calculated as follows: [4.44 (MBq) x 100/24 hours uptake (%)] x TV. All patients are evaluated for thyroid function and TV at 3, 6, 12, 18 and 24 months after treatment, since we postulate that major reduction in thyroid volume will occur 1 year after 131 I therapy. Results: Up to now 16 pts were treated with 131 I (mean activity: 512 MBq) and no side effects from 131 I and lithium therapy were reported. Four out of 5 pts evaluated at 3 months (2 of group 1 and 3 of group 2) had a reduction in TV (mean value: 8.8 ml). Five out of 10 pts had sub-clinical hyperthyroidism at 1 week, likely as a consequence of thyroid tissue destruction. Conclusion: Our preliminary results suggest the safety and effectiveness of 131 I treatment in NTMG. We expect to clarify the role of lithium administration in improving 131 I efficacy. This therapy could have a future role in patients with NTMG that can't be submitted to surgery

  18. A Paleoevaporation Proxy Using Compound Specific Stable Isotope Measurements from Peatland Biomarkers

    Science.gov (United States)

    Wang, J.; Nichols, J. E.; Huang, Y.

    2009-12-01

    It is important to understand how evaporation from wetlands changes with climate. To do this, we have developed a paleoevaporation proxy for use in ombrotrophic peatland sediments. Using compound specific hydrogen isotopic ratios of vascular plant and Sphagnum biomarkers, we can quantitatively reconstruct past changes in evaporation. The contrast in H isotopic ratios of water available to living Sphagnum and water in the acrotelm can be used to estimate “f”—the fraction of water remaining after evaporation. Vascular plant leaf waxes record H isotopic ratios of precipitation which is little affected by evaporation, whereas the Sphagnum biomarker, C23 n-alkane, records H isotopic ratios of the water inside its cells and between its leaves, which is strongly affected by evaporation at the bog surface. Evaporation changes can then be calculated with the H-isotopic ratios of the two types of biomarkers. We calibrated the apparent fractionation of D/H ratios from source water to C23 n-alkane with lab-grown Sphagnum. We also present several reconstructions of paleoevaporation from peatlands throughout eastern North America. By comparison with overall hydrologic balance, we are able to understand the varying role of evaporation in the hydrologic system in both time and space.

  19. Understanding the Formation of Kinetically Stable Compounds and the Development of Thin Film Pair Distribution Function Analysis

    Science.gov (United States)

    Wood, Suzannah Rebecca

    Navigating the synthesis landscape poses many challenges when developing novel solid state materials. Advancements in both synthesis and characterization are necessary to facilitate the targeting of specific materials. This dissertation discusses the formation of chalcogenide heterostructures and their properties in the first part and the development of thin film pair distribution function analysis (tfPDF) in the second part. The heterostructures were formed by the self-assembly of designed precursors deposited by physical vapor deposition in a modulated elemental reactants approach, which provides the control and predictability to synthesis. Specifically, a series of (BiSe)1+delta(TiSe2) n, where n = 2,3,&4, were synthesized to explore the extent of charge transfer from the BiSe to TiSe2 layers. To further explore the role Bi plays in charge donation, a family of structurally similar compounds, (Bix Sn1-xSe)1+deltaTiSe2, where 0≥x≥1, were synthesized and characterized. Electrical measurements show doping efficiency decreases as x increases, correlated with the structural distortion and the formation of periodic antiphase boundaries containing Bi-Bi pairs. The first heterostructures composed of three unique structural types were synthesized and Bi2Se3 layer thickness was used to tune electrical properties and further explore charge transfer. To better understand the potential energy landscape on which these kinetically stable compounds exist, two investigations were undertaken. The first was a study of the formation and subsequent decomposition of [(BiSe)1+delta]n(TiSe2)n compounds, where n= 2&3, the second an investigation of precursor structure for thermodynamically stable FeSb2 and kinetically stable FeSb3. The second section describes the development of thin film pair distribution function analysis, a technique in which total scattering data for pair distribution function (PDF) analysis is obtained from thin films, suitable for local structure analysis

  20. Syntheses and properties of several metastable and stable hydrides derived from intermetallic compounds under high hydrogen pressure

    Energy Technology Data Exchange (ETDEWEB)

    Filipek, S.M., E-mail: sfilipek@unipress.waw.pl [Institute of High Pressure Physics PAS, ul. Sokolowska 29, 01-142 Warsaw (Poland); Paul-Boncour, V. [ICMPE-CMTR, CNRS-UPEC, 2-8 rue Henri Dunant, 94320 Thiais (France); Liu, R.S. [Department of Chemistry, National Taiwan University, Taipei 106, Taiwan (China); Jacob, I. [Unit Nuclear Eng., Ben Gurion University of the Negev, Beer-Sheva (Israel); Tsutaoka, T. [Dept. of Sci. Educ., Grad. School of Educ., Hiroshima University, Hiroshima (Japan); Budziak, A. [Institute of Nuclear Physics PAS, 31-342 Kraków (Poland); Morawski, A. [Institute of High Pressure Physics PAS, ul. Sokolowska 29, 01-142 Warsaw (Poland); Sugiura, H. [Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama 236-0027 (Japan); Zachariasz, P. [Institute of Electron Technology Cracow Division, ul. Zablocie 39, 30-701 Krakow (Poland); Dybko, K. [Institute of Physics, PAS, 02-668 Warsaw (Poland); Diduszko, R. [Tele and Radio Research Institute, ul. Ratuszowa 11, Warsaw (Poland)

    2016-12-01

    Brief summary of our former work on high hydrogen pressure syntheses of novel hydrides and studies of their properties is supplemented with new results. Syntheses and properties of a number of hydrides (unstable, metastable or stable in ambient conditions) derived under high hydrogen pressure from intermetallic compounds, like MeT{sub 2}, MeNi{sub 5}, Me{sub 7}T{sub 3}, Y{sub 6}Mn{sub 23} and YMn{sub 12} (where Me = zirconium, yttrium or rare earth; T = transition metal) are presented. Stabilization of ZrFe{sub 2}H{sub 4} due to surface phenomena was revealed. Unusual role of manganese in hydride forming processes is pointed out. Hydrogen induced phase transitions, suppression of magnetism, antiferromagnetic-ferromagnetic and metal-insulator or semimetal-metal transitions are described. Equations of state (EOS) of hydrides submitted to hydrostatic pressures up to 30 GPa are presented and discussed.

  1. Compound specific stable isotopes as probes for distinguishing the sources of biomolecules in terrestrial and extraterrestrial materials

    Science.gov (United States)

    Engel, M. H.; Macko, S. A.

    2003-04-01

    Life on Earth consists of orderly arrangements of several key types of organic compounds (amino acids, sugars, fatty acids, nucleic bases) that are the building blocks of proteins, carbohydrates, lipids and nucleotides. Subsequent to death, macromolecules are commonly broken down to their molecular constituents or other similar scale components. Thus, in ancient terrestrial and extraterrestrial materials, it is far more likely to expect the presence of simple compounds such as amino acids rather than the proteins from which they were possibly derived. Given that amino acids, for example, are common components of all extinct and extant organisms, the challenge has been to develop methods for distinguishing their sources. Stable isotopes are powerful probes for determining the origins of organic matter. Amino acid constituents of all organisms on Earth exhibit characteristic stable isotope compositions owing to fractionations associated with their biosynthesis. These fractionations are distinct from those observed for amino acids formed by abiotic processes. Thus it should be possible to use isotopes as probes for determining whether amino acids in ancient rocks on Earth are biotic or abiotic, based on their relative isotopic compositions. Also, owing to differences in the isotope compositions of precursors, amino acids in extraterrestrial materials such as carbonaceous meteorites are moderately to substantially enriched in the heavy isotopes of C, N and H relative to terrestrial amino acids. Assuming that the isotope compositions of the gaseous components of, for example, the Martian atmosphere were distinct from Earth at such time when organic molecules may have formed, it should be possible to distinguish these components from terrestrial contaminants by determining their isotope compositions and/or those of their respective enantiomers. Also, if life as we know it existed on another planet such as Mars, fractionations characteristic of biosynthesis should be

  2. Degradation of sulfamethoxazole using ozone and chlorine dioxide - Compound-specific stable isotope analysis, transformation product analysis and mechanistic aspects.

    Science.gov (United States)

    Willach, Sarah; Lutze, Holger V; Eckey, Kevin; Löppenberg, Katja; Lüling, Michelle; Terhalle, Jens; Wolbert, Jens-Benjamin; Jochmann, Maik A; Karst, Uwe; Schmidt, Torsten C

    2017-10-01

    The sulfonamide antibiotic sulfamethoxazole (SMX) is a widely detected micropollutant in surface and groundwaters. Oxidative treatment with e.g. ozone or chlorine dioxide is regularly applied for disinfection purposes at the same time exhibiting a high potential for removal of micropollutants. Especially for nitrogen containing compounds such as SMX, the related reaction mechanisms are largely unknown. In this study, we systematically investigated reaction stoichiometry, product formation and reaction mechanisms in reactions of SMX with ozone and chlorine dioxide. To this end, the neutral and anionic SMX species, which may occur at typical pH-values of water treatment were studied. Two moles of chlorine dioxide and approximately three moles of ozone were consumed per mole SMX degraded. Oxidation of SMX with ozone and chlorine dioxide leads in both cases to six major transformation products (TPs) as revealed by high-resolution mass spectrometry (HRMS). Tentatively formulated TP structures from other studies could partly be confirmed by compound-specific stable isotope analysis (CSIA). However, for one TP, a hydroxylated SMX, it was not possible by HRMS alone to identify whether hydroxylation occurred at the aromatic ring, as suggested in literature before, or at the anilinic nitrogen. By means of CSIA and an analytical standard it was possible to identify sulfamethoxazole hydroxylamine unequivocally as one of the TPs of the reaction of SMX with ozone as well as with chlorine dioxide. H-abstraction and electron transfer at the anilinic nitrogen are suggested as likely initial reactions of ozone and chlorine dioxide, respectively, leading to its formation. Oxidation of anionic SMX with ozone did not show any significant isotopic fractionation whereas the other reactions studied resulted in a significant carbon isotope fractionation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Thermodynamic behavior of very stable binary compounds with a wide homogeneity range: Their influence in the liquid phase in ternary and higher component systems in the solid state

    International Nuclear Information System (INIS)

    Hoch, M.

    1988-01-01

    The Hoch-Arpshofen model is combined with the Schottky-Wagner disorder model to describe first binary liquid systems, where a very stable solid protrudes into the liquid. We analyze the systems K-I 2 , Cs-I 2 , U-UO 3 , Ag-S and Al-Sb. The system Al-Sb can be described as Al-Sb and as Al-AlSb-Sb. Then we examine the Al-Co, Al-Ni, and Al-Fe systems to describe the stable compounds CoAl, NiAl, and FeAl, which all have a wide homogeneity range in the solid state. Here the Schottky-Wagner model is sufficient. Finally we describe a model which treats the influence of these stable binary compounds in ternary and larger systems such as Al-Cr-Ni and Al-Cr-Fe, again in the solid state. (orig./IHOE) [de

  4. Novel proxies for reconstructing paleohydrology from ombrotrophic peatlands: biomarker and compound-specific H and C stable isotope ratios

    Science.gov (United States)

    Wang, J.; Nichols, J. E.; Huang, Y.

    2008-12-01

    Ombrotrophic peatlands are excellent archives for paleohydrologic information because they are hydrologically isolated from their surroundings. However, quantitative proxies for deciphering peatland archives are lacking. Here, we present development and application of novel organic geochemical methods for quantitative reconstruction of paleohydrology from the ombrotrophic sediments, and comparison of organic geochemical data with conventional paleoecological proxies. Application of these methods to the sediments of several North American and European peatlands has revealed significant changes in the hydroclimate throughout the Holocene. The plant assemblage living at the surface of the peatland is tightly controlled by surface moisture. Under wet conditions, Sphagnum mosses, with no active mechanism for drawing water from below the surface of the peatland, are dominant. During dry conditions, vascular plants are more productive relative to Sphagnum. A ratio of the abundance of two biomarkers representing Sphagnum and vascular plants sensitively records changes in hydrologic balance (Nichols et al., 2006, Org. Geochem. 37, 1505-1513). We have further developed stable isotope models to compute climate parameters from compound-specific H and C isotope ratios of biomarkers to create a more comprehensive climate reconstruction. Vascular plant leaf waxes carry the D/H ratio signature of precipitation that is little affected by evaporation, whereas the Sphagnum biomarker records isotopic ratios of the water at the peatland surface, which is strongly enriched by evaporation. Evaporation amount can be calculated using the differences between D/H ratios of the two types of biomarkers. C isotope ratios of Sphagnum biomarkers can also be used to quantify surface wetness. Methanotrophic bacteria live symbiotically with Sphagnum, providing isotopically light carbon for photosynthesis. These bacteria are more active when the Sphagnum is wet, thus providing more 13C-depleted CO2

  5. Active prey selection in two pelagic copepods feeding on potentially toxic and non-toxic dinoflagellates

    DEFF Research Database (Denmark)

    Schultz, Mette; Kiørboe, Thomas

    2009-01-01

    Grazing on two red tide dinoflagellates, the potentially toxic Karenia mikimotoi and the non-toxic Gyrodinium instriatum, was examined in two species of marine copepods, Pseudocalanus elongatus and Temora longicornis. Both copepods cleared K. mikimotoi at rates that were a little lower but compar......Grazing on two red tide dinoflagellates, the potentially toxic Karenia mikimotoi and the non-toxic Gyrodinium instriatum, was examined in two species of marine copepods, Pseudocalanus elongatus and Temora longicornis. Both copepods cleared K. mikimotoi at rates that were a little lower...

  6. Functional connectivity of coral reef fishes in a tropical seascape assessed by compound-specific stable isotope analyses

    KAUST Repository

    McMahon, Kelton W.

    2011-01-01

    The ecological integrity of tropical habitats, including mangroves, seagrass beds and coral reefs, is coming under increasing pressure from human activities. Many coral reef fish species are thought to use mangroves and seagrass beds as juvenile nurseries before migrating to coral reefs as adults. Identifying essential habitats and preserving functional linkages among these habitats is likely necessary to promote ecosystem health and sustainable fisheries on coral reefs. This necessitates quantitative assessment of functional connectivity among essential habitats at the seascape level. This thesis presents the development and first application of a method for tracking fish migration using amino acid (AA) δ13C analysis in otoliths. In a controlled feeding experiment with fish reared on isotopically distinct diets, we showed that essential AAs exhibited minimal trophic fractionation between consumer and diet, providing a δ13C record of the baseline isoscape. We explored the potential for geochemical signatures in otoliths of snapper to act as natural tags of residency in seagrass beds, mangroves and coral reefs in the Red Sea, Caribbean Sea and Eastern Pacific Ocean. The δ13C values of otolith essential AAs varied as a function of habitat type and provided a better tracer of residence in juvenile nursery habitats than conventional bulk stable isotope analyses (SIA). Using our otolith AA SIA approach, we quantified the relative contribution of coastal wetlands and reef habitats to Lutjanus ehrenbergii populations on coastal, shelf and oceanic coral reefs in the Red Sea. L. ehrenbergii made significant ontogenetic migrations, traveling more than 30 km from juvenile nurseries to coral reefs and across deep open water. Coastal wetlands were important nurseries for L. ehrenbergii; however, there was significant plasticity in L. ehrenbergii juvenile habitat requirements. Seascape configuration played an important role in determining the functional connectivity of L

  7. Branched GDGTs in Lacustrine Environments: Tracing Allochthonous and Autochthonous Sources Using Compound-Specific Stable Carbon Isotope Analysis

    Science.gov (United States)

    Weber, Y.; S Sinninghe Damsté, J.; Lehmann, M. F.; Niemann, H.; Schubert, C. J.

    2015-12-01

    Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are bacterial membrane lipids that are ubiquitous in soils and peat, as well as in sediments of lakes, rivers and coastal marine environments. It has been found that the distribution of brGDGTs changes systematically with ambient temperature and pH, attesting to their potential as proxy indicators for paleoclimatic reconstruction. In lacustrine sedimentary archives, brGDGTs can originate from two sources: (1) allochthonous soil organic matter and (2) autochthonous brGDGTs produced within the lake system, both of which display fairly distinct temperature-brGDGT relationships. Until now, disentangling the relative contribution of these sources was impossible, complicating the use of brGDGTs for quantitative paleotemperature reconstructions. BrGDGTs in soils display a narrow range with respect to their stable carbon isotope composition (δ13C), generally between -27 and -30 ‰, whereas we recently found contrasting δ13C values as low as -43 ‰ to -46 ‰ for brGDGTs in sediments of a small Alpine lake. To trace the origin of this distinct isotope signal, we determined the 13C content of brGDGTs in suspended particulate matter (SPM) from the water column of Lake Lugano (Switzerland). The δ13C of SPM-derived brGDGTs decreased systematically from -34 ‰ in the mixolimnion to -41 ‰ in the anoxic monimolimnion of Lake Lugano, providing evidence for aquatic in situ production of 13C-depleted brGDGT. In order to study whether the negative δ13C offset of water column- vs. soil-derived brGDGTs may serve as an indicator for lacustrine brGDGT production, we also analyzed surface sediments from 36 lakes across the Alpine Region. In most (~85 %) of the studied lake sediments, the δ13C of brGDGTs ranged between -34 ‰ and -45 ‰, indicating predominance or a substantial contribution of aquatically produced brGDGTs. However, in some lakes (~15 %) δ13C values between -27 ‰ and -30 ‰ suggest a mainly

  8. Tracing the link between plant volatile organic compound emissions and CO2 fluxes and by stable isotopes

    Science.gov (United States)

    Werner, Christiane; Wegener, Frederik; Jardine, Kolby

    2015-04-01

    The vegetation exerts a large influence on the atmosphere through the emission of volatile organic compounds (VOCs) and the emission and uptake of the greenhouse gas CO2. Despite the enormous importance, processes controlling plant carbon allocation into primary and secondary metabolism, such as photosynthetic carbon uptake, respiratory CO2 emission and VOC synthesis, remains unclear. Moreover, vegetation-atmosphere CO2 exchange is associated with a large isotopic imprint due to photosynthetic carbon isotope discrimination and 13C-fractionation during respiratory CO2 release1. The latter has been proposed to be related to carbon partitioning in the metabolic branching points of the respiratory pathways and secondary metabolism, which are linked via a number of interfaces including the central metabolite pyruvate. Notably, it is a known substrate in a large array of secondary pathways leading to the biosynthesis of many volatile organic compounds (VOCs), such as volatile isoprenoids, oxygenated VOCs, aromatics, fatty acid oxidation products, which can be emitted by plants. Here we investigate the linkage between VOC emissions, CO2 fluxes and associated isotope effects based on simultaneous real-time measurements of stable carbon isotope composition of branch respired CO2 (CRDS) and VOC fluxes (PTR-MS). We utilized positionally specific 13C-labeled pyruvate branch feeding experiments in the mediterranean shrub (Halimium halimifolium) to trace the partitioning of C1, C2, and C3 carbon atoms of pyruvate into VOCs versus CO2 emissions in the light and in the dark. In the light, we found high emission rates of a large array of VOC including volatile isoprenoids, oxygenated VOCs, green leaf volatiles, aromatics, sulfides, and nitrogen containing VOCs. These observations suggest that in the light, H. halimifolium dedicates a high carbon flux through secondary biosynthetic pathways including the pyruvate dehydrogenase bypass, mevalonic acid, MEP/DOXP, shikimic acid, and

  9. Economic benefits of the use of non-toxic mono-propellants for spacecraft applications

    NARCIS (Netherlands)

    Bombelli, V.; Simon, D.; Marée, T.; Moerel, J.L.

    2003-01-01

    The European Space Agency and other institutions have identified the use of non-toxic (or "green") propellants as a substantial cost saving opportunity in manufacturing and ground operating of spacecrafts. This paper attempts to identify and quantify this potential by replacing, in the near future,

  10. Phylogenetic diversity of bacteria associated with toxic and non-toxic ...

    African Journals Online (AJOL)

    Phylogenetic diversity of bacteria associated with toxic and non-toxic strains of Alexandrium minutum. L Palacios, B Reguera, J Franco, I Marín. Abstract. Marine planktonic dinoflagellates are usually associated with bacteria, some of which seem to have a symbiotic relation with the dinoflagellate cells. The role of bacteria in ...

  11. Cysteine as a non toxic corrosion inhibitor for copper alloys in conservation

    DEFF Research Database (Denmark)

    Gravgaard, Mari; van Lanschot, Jettie

    2012-01-01

    studies of colour changes in the corrosion products. The results obtained in this article demonstrate that cysteine could be a non-toxic alternative to BTA. Cysteine performed as well as BTA on pre-corroded coupons with bronze disease in high humidity and showed acceptable results during testing...

  12. Assessment of Cost Impacts of Using Non-Toxic Propulsion in Satellites

    Science.gov (United States)

    Schiebener, P. J.; Gies, O.; Stuhlberger, J.; Schmitz, H.-D.

    2002-01-01

    The growing costs of space missions, the need for increased mission performance, and concerns associated with environmental issues deeply influence propulsion system design and propellant selection criteria. A propellant's performance was defined in the past exclusively in terms of specific impulse and density, but now high-performance, non-toxic, non-sophisticated mono- propellant systems are key drivers, and are considered for development to replace the traditional hydrazine (N2H4) mono-propellant thrusters. The mono-propellants under consideration are propellant formulations, which should be environmentally friendly, should have a high density, equal or better performance and better thermal characteristics than hydrazine. These considerations raised interest specially in the candidates of Hydroxylammonium Nitrate (HAN)-based propellants, Ammoniumdinitramide (ADN)-based propellants, Tri-ethanol (TEAN)-based propellants, Hydrazinium Nitroformate (HNF)-based propellants, Hydrogen Peroxide (H2O2)-based propellants. A near-term objective in consideration of satellite related process optimisation is to significantly reduce on-ground operations costs and at the same time improve mission performance. A far-term objective is to obtain a system presenting a very high performance, illustrated by a high specific impulse. Moving to a "non-toxic" propulsion system seems to be a solution to these two goals. The sought after benefits for non-toxic spacecraft mono-propellant propulsion are under investigation taking into account the four main parameters which are mandatory for customer satisfaction while meeting the price constraints: - Reliability, availability, maintainability and safety, - Manufacturing, assembly, integration and test, - Launch preparation and support, - Ground support equipment. These benefits of non-toxic mono-propellants can be proven by various examples, like an expected reduction of development costs due the non-toxicity of propellants which might allow

  13. The Effect of Digestive Capacity on the Intake Rate of Toxic and Non-Toxic Prey in an Ecological Context.

    Directory of Open Access Journals (Sweden)

    Thomas Oudman

    Full Text Available Digestive capacity often limits food intake rate in animals. Many species can flexibly adjust digestive organ mass, enabling them to increase intake rate in times of increased energy requirement and/or scarcity of high-quality prey. However, some prey species are defended by secondary compounds, thereby forcing a toxin limitation on the forager's intake rate, a constraint that potentially cannot be alleviated by enlarging digestive capacity. Hence, physiological flexibility may have a differential effect on intake of different prey types, and consequently on dietary preferences. We tested this effect in red knots (Calidris canutus canutus, medium-sized migratory shorebirds that feed on hard-shelled, usually mollusc, prey. Because they ingest their prey whole and crush the shell in their gizzard, the intake rate of red knots is generally constrained by digestive capacity. However, one of their main prey, the bivalve Loripes lucinalis, imposes a toxin constraint due to its symbiosis with sulphide-oxidizing bacteria. We manipulated gizzard sizes of red knots through prolonged exposure to hard-shelled or soft foods. We then measured maximum intake rates of toxic Loripes versus a non-toxic bivalve, Dosinia isocardia. We found that intake of Dosinia exponentially increased with gizzard mass, confirming earlier results with non-toxic prey, whereas intake of Loripes was independent of gizzard mass. Using linear programming, we show that this leads to markedly different expected diet preferences in red knots that try to maximize energy intake rate with a small versus a large gizzard. Intra- and inter-individual variation in digestive capacity is found in many animal species. Hence, the here proposed functional link with individual differences in foraging decisions may be general. We emphasize the potential relevance of individual variation in physiology when studying trophic interactions.

  14. (Pyridine)(tetrahydroborato)zinc complex, (Zn(BH4)2(py)), as a new stable, efficient and chemoselective reducing agent for reduction of carbonyl compounds

    International Nuclear Information System (INIS)

    Zeynizadeh, Behzad; Faraji, Fariba

    2003-01-01

    (Pyridine)(tetrahydroborato)zinc complex, (Zn(BH 4 ) 2 (py)), as a stable white solid, was prepared quantitatively by complexation of an equimolar amount of zinc tetrahydroborate and pyridine at room temperature. This reagent can easily reduce variety of carbonyl compounds such as aldehydes, ketones, acyloins, α-diketones and α,β-unsaturated carbonyl compounds to their corresponding alcohols in good to excellent yields. Reduction reactions were performed in ether or THF at room temperature or under reflux conditions. In addition, the chemoselective reduction of aldehydes over ketones was accomplished successfully with this reducing agent

  15. (Pyridine)(tetrahydroborato)zinc complex, (Zn(BH{sub 4}){sub 2}(py)), as a new stable, efficient and chemoselective reducing agent for reduction of carbonyl compounds

    Energy Technology Data Exchange (ETDEWEB)

    Zeynizadeh, Behzad; Faraji, Fariba [Urima Univ., Urima (Iran, Islamic Republic of)

    2003-04-01

    (Pyridine)(tetrahydroborato)zinc complex, (Zn(BH{sub 4}){sub 2}(py)), as a stable white solid, was prepared quantitatively by complexation of an equimolar amount of zinc tetrahydroborate and pyridine at room temperature. This reagent can easily reduce variety of carbonyl compounds such as aldehydes, ketones, acyloins, {alpha}-diketones and {alpha},{beta}-unsaturated carbonyl compounds to their corresponding alcohols in good to excellent yields. Reduction reactions were performed in ether or THF at room temperature or under reflux conditions. In addition, the chemoselective reduction of aldehydes over ketones was accomplished successfully with this reducing agent.

  16. Complementing approaches to demonstrate chlorinated solvent biodegradation in a complex pollution plume: mass balance, PCR and compound-specific stable isotope analysis.

    OpenAIRE

    Courbet Christelle; Rivière Agnès; Jeannottat Simon; Rinaldi Sandro; Hunkeler Daniel; Bendjoudi Hocine; De Marsily Ghislain

    2011-01-01

    This work describes the use of different complementing methods (mass balance polymerase chain reaction assays and compound specific stable isotope analysis) to demonstrate the existence and effectiveness of biodegradation of chlorinated solvents in an alluvial aquifer. The solvent contaminated site is an old chemical factory located in an alluvial plain in France. As most of the chlorinated contaminants currently found in the groundwater at this site were produced by local industries at vario...

  17. Stable and High OSNR Compound Linear-Cavity Single-Longitudinal-Mode Erbium-Doped Silica Fiber Laser Based on an Asymmetric Four-Cavity Structure

    International Nuclear Information System (INIS)

    Feng Ting; Yan Feng-Ping; Li Qi; Peng Wan-Jing; Feng Su-Chun; Wen Xiao-Dong; Tan Si-Yu; Liu Peng

    2012-01-01

    We propose a stable and high optical signal-to-noise ratio (OSNR) compound linear-cavity single-longitudinal-mode (SLM) erbium-doped silica fiber laser. It consists of three uniform fiber Bragg gratings (FBGs) and two fiber couplers to form a simple asymmetric four-cavity structure to select the longitudinal mode. The stable SLM operation at the wavelength of 1544.053 nm with a 3 dB bandwidth of 0.014 nm and an OSNR of ∼60 dB was verified experimentally. Under laboratory conditions, a power fluctuation performance of less than 0.05 dB for 5 h and wavelength variation of less than 0.01 nm for about 150 min is demonstrated. Finally, the characteristic of laser output power as a function of pump power is investigated. The proposed system provides a simple and cost-effective approach to realize a stable SLM fiber laser

  18. Apportioning sources of organic matter in streambed sediments: An integrated molecular and compound-specific stable isotope approach

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, Richard J., E-mail: Richard.J.Cooper@uea.ac.uk [School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ (United Kingdom); Pedentchouk, Nikolai; Hiscock, Kevin M.; Disdle, Paul [School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ (United Kingdom); Krueger, Tobias [IRI THESys, Humboldt University, 10099 Berlin (Germany); Rawlins, Barry G. [British Geological Survey, Keyworth, Nottingham NG12 5GG (United Kingdom)

    2015-07-01

    We present a novel application for quantitatively apportioning sources of organic matter in streambed sediments via a coupled molecular and compound-specific isotope analysis (CSIA) of long-chain leaf wax n-alkane biomarkers using a Bayesian mixing model. Leaf wax extracts of 13 plant species were collected from across two environments (aquatic and terrestrial) and four plant functional types (trees, herbaceous perennials, and C{sub 3} and C{sub 4} graminoids) from the agricultural River Wensum catchment, UK. Seven isotopic (δ{sup 13}C{sub 27}, δ{sup 13}C{sub 29}, δ{sup 13}C{sub 31}, δ{sup 13}C{sub 27–31}, δ{sup 2}H{sub 27}, δ{sup 2}H{sub 29}, and δ{sup 2}H{sub 27–29}) and two n-alkane ratio (average chain length (ACL), carbon preference index (CPI)) fingerprints were derived, which successfully differentiated 93% of individual plant specimens by plant functional type. The δ{sup 2}H values were the strongest discriminators of plants originating from different functional groups, with trees (δ{sup 2}H{sub 27–29} = − 208‰ to − 164‰) and C{sub 3} graminoids (δ{sup 2}H{sub 27–29} = − 259‰ to − 221‰) providing the largest contrasts. The δ{sup 13}C values provided strong discrimination between C{sub 3} (δ{sup 13}C{sub 27–31} = − 37.5‰ to − 33.8‰) and C{sub 4} (δ{sup 13}C{sub 27–31} = − 23.5‰ to − 23.1‰) plants, but neither δ{sup 13}C nor δ{sup 2}H values could uniquely differentiate aquatic and terrestrial species, emphasizing a stronger plant physiological/biochemical rather than environmental control over isotopic differences. ACL and CPI complemented isotopic discrimination, with significantly longer chain lengths recorded for trees and terrestrial plants compared with herbaceous perennials and aquatic species, respectively. Application of a comprehensive Bayesian mixing model for 18 streambed sediments collected between September 2013 and March 2014 revealed considerable temporal variability in the

  19. Functional connectivity of coral reef fishes in a tropical seascape assessed by compound-specific stable isotope analyses

    KAUST Repository

    McMahon, Kelton W.

    2011-01-01

    . The compound-specific SIA approach presented in this thesis will be particularly valuable for tracking the movement of species and life-stages not amenable to conventional tagging techniques. This thesis provides quantitative scientific support for establishing

  20. Do thyroid-stimulating immunoglobulins cause non-toxic and toxic multinodular goitre

    International Nuclear Information System (INIS)

    Brown, R.S.; Jackson, I.M.D.; Pohl, S.L.; Reichlin, S.

    1978-01-01

    The prevalence of serum thyroid-stimulating immunoglobulins, (T.S.I.) in a variety of thyroid diseases was determined in 96 patients and 35 normal controls. Significantly elevated levels of T.S.I. were found not only in patients with Graves' disease and Hashimoto's thyroiditis but also in those with non-toxic and multinodular goitre, whereas patients with a single autonomously functioning thyroid nodule, with subacute thyroiditis, and with 'hyperthyroiditis' had levels which did not differ from those in the controls. it is postulated that non-toxic multinodular goitre, like Graves' disease, may result from increased circulating T.S.I. which in some cases may be present in sufficient concentration to cause thyrotoxicosis. (author)

  1. [Individualized clinical treatment from the prospective of hepatotoxicity of non-toxic traditional Chinese medicine].

    Science.gov (United States)

    Yang, Nan; Chen, Juan; Hou, Xue-Feng; Song, Jie; Feng, Liang; Jia, Xiao-Bin

    2017-04-01

    Traditional Chinese medicine has a long history in clinical application, and been proved to be safe and effective. In recent years, the toxicity and side-effects caused by the western medicine have been attracted much attention. As a result, increasing people have shifted their attention to traditional Chinese medicine. Nonetheless, due to the natural origin of traditional Chinese medicine and the lack of basic knowledge about them, many people mistakenly consider the absolute safety of traditional Chinese medicine, except for well-known toxic ones, such as arsenic. However, according to the clinical practices and recent studies, great importance shall be attached to the toxicity of non-toxic traditional Chinese medicine, in particular the hepatotoxicity. Relevant studies indicated that the toxicity of non-toxic traditional Chinese medicine is closely correlated with individual gene polymorphism and constitution. By discussing the causes and mechanisms of the hepatotoxicity induced by non-toxic traditional Chinese medicine in clinical practices, we wrote this article with the aim to provide new ideas for individualized clinical therapy of traditional Chinese medicine and give guidance for rational and safe use of traditional Chinese medicine. Copyright© by the Chinese Pharmaceutical Association.

  2. A novel non-toxic combined CTA1-DD and ISCOMS adjuvant vector for effective mucosal immunization against influenza virus.

    Science.gov (United States)

    Eliasson, Dubravka Grdic; Helgeby, Anja; Schön, Karin; Nygren, Caroline; El-Bakkouri, Karim; Fiers, Walter; Saelens, Xavier; Lövgren, Karin Bengtsson; Nyström, Ida; Lycke, Nils Y

    2011-05-23

    Here we demonstrate that by using non-toxic fractions of saponin combined with CTA1-DD we can achieve a safe and above all highly efficacious mucosal adjuvant vector. We optimized the construction, tested the requirements for function and evaluated proof-of-concept in an influenza A virus challenge model. We demonstrated that the CTA1-3M2e-DD/ISCOMS vector provided 100% protection against mortality and greatly reduced morbidity in the mouse model. The immunogenicity of the vector was superior to other vaccine formulations using the ISCOM or CTA1-DD adjuvants alone. The versatility of the vector was best exemplified by the many options to insert, incorporate or admix vaccine antigens with the vector. Furthermore, the CTA1-3M2e-DD/ISCOMS could be kept 1 year at 4°C or as a freeze-dried powder without affecting immunogenicity or adjuvanticity of the vector. Strong serum IgG and mucosal IgA responses were elicited and CD4 T cell responses were greatly enhanced after intranasal administration of the combined vector. Together these findings hold promise for the combined vector as a mucosal vaccine against influenza virus infections including pandemic influenza. The CTA1-DD/ISCOMS technology represents a breakthrough in mucosal vaccine vector design which successfully combines immunomodulation and targeting in a safe and stable particulate formation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. A Stable, Magnetic, and Metallic Li3O4 Compound as a Discharge Product in a Li-Air Battery.

    Science.gov (United States)

    Yang, Guochun; Wang, Yanchao; Ma, Yanming

    2014-08-07

    The Li-air battery with the specific energy exceeding that of a Li ion battery has been aimed as the next-generation battery. The improvement of the performance of the Li-air battery needs a full resolution of the actual discharge products. Li2O2 has been long recognized as the main discharge product, with which, however, there are obvious failures on the understanding of various experimental observations (e.g., magnetism, oxygen K-edge spectrum, etc.) on discharge products. There is a possibility of the existence of other Li-O compounds unknown thus far. Here, a hitherto unknown Li3O4 compound as a discharge product of the Li-air battery was predicted through first-principles swarm structure searching calculations. The new compound has a unique structure featuring the mixture of superoxide O2(-) and peroxide O2(2-), the first such example in the Li-O system. The existence of superoxide O2(-) creates magnetism and hole-doped metallicity. Findings of Li3O4 gave rise to direct explanations of the unresolved experimental magnetism, triple peaks of oxygen K-edge spectra, and the Raman peak at 1125 cm(-1) of the discharge products. Our work enables an opportunity for the performance of capacity, charge overpotential, and round-trip efficiency of the Li-air battery.

  4. Measuring volatile organic compounds and stable isotopes emitted from trees and soils of the Biosphere 2 Rainforest

    Science.gov (United States)

    Meraz, J. C.; Meredith, L. K.; Van Haren, J. L. M.; Volkmann, T. H. M.

    2017-12-01

    Rainforest trees and soils play an important role in volatile organic compound (VOC) emissions. It is known that many rainforest tree species emit these organic compounds, such as terpenes, which can have an impact on the atmosphere and can be indicative of their metabolic functions. Some VOCs also absorb infrared radiation at wavelengths at which water isotopes are measured with laser spectrometers. Normal concentrations are not high enough for ambient sampling, but increased concentrations resulting from soil and plant samples extracted using equilibrium methods affect observed isotope ratios. There is thus a need to characterize volatile emissions from soil and plant samples, and to develop better methods to account for VOC interference during water isotope measurements. In this study, we collected soil and leaf samples from plants of the Biosphere 2 Rainforest Biome, a mesocosm system created to stimulate natural tropical rainforest habitats . Volatile concentrations were measured using a Gasmet DX4015 FTIR analyzer and a custom sampling system with sulfur hexafluoride (SF6) used as a tracer gas to test for leakage, and a commercial laser spectrometer was used for isotopic analysis. We determined that the different types of tree species emit different kinds of VOCs, such as isoprenes, alcohols, and aldehydes, that will potentially have to be accounted for. This study will help build the understanding of which organic compounds are emitted and develop new methods to test for water isotopes and gas fluxes in clear and precise measures. Such measures can help characterize the functioning of environmental systems such as the Biosphere 2 Rainforest Biome.

  5. Characterization of ZnS thin films synthesized through a non-toxic precursors chemical bath

    Energy Technology Data Exchange (ETDEWEB)

    Rodríguez, C.A. [Department of Materials Engineering, Faculty of Engineering, University of Concepción, Edmundo Larenas 270, Concepción 4070409 (Chile); Sandoval-Paz, M.G. [Department of Physics, Faculty of Physics and Mathematics, University of Concepción, Concepción (Chile); Cabello, G. [Department of Basic Sciences, Faculty of Sciences, University of Bío-Bío, Campus Fernando May, Chillán (Chile); Flores, M.; Fernández, H. [Department of Physics, Faculty of Physics and Mathematics, University of Chile, Beauchef 850, Santiago (Chile); Carrasco, C., E-mail: ccarrascoc@udec.cl [Department of Materials Engineering, Faculty of Engineering, University of Concepción, Edmundo Larenas 270, Concepción 4070409 (Chile)

    2014-12-15

    Highlights: • High quality ZnS thin films have been deposited by chemical bath deposition technique from a non-toxic precursor’s solution. • Nanocrystalline ZnS thin films with large band gap energy were synthesized without using ammonia. • Evidence that the growing of the thin films is carried out by means of hydroxide mechanism was found. • The properties of these ZnS thin films are similar and in some cases better than the corresponding ones produced using toxic precursors such as ammonia. - Abstract: In solar cells, ZnS window layer deposited by chemical bath technique can reach the highest conversion efficiency; however, precursors used in the process normally are materials highly volatile, toxic and harmful to the environment and health (typically ammonia and hydrazine). In this work the characterization of ZnS thin films deposited by chemical bath in a non-toxic alkaline solution is reported. The effect of deposition technique (growth in several times) on the properties of the ZnS thin film was studied. The films exhibited a high percentage of optical transmission (greater than 80%); as the deposition time increased a decreasing in the band gap values from 3.83 eV to 3.71 eV was observed. From chemical analysis, the presence of ZnS and Zn(OH){sub 2} was identified and X-ray diffraction patterns exhibited a clear peak corresponding to ZnS hexagonal phase (1 0 3) plane, which was confirmed by electron diffraction patterns. From morphological studies, compact samples with well-defined particles, low roughness, homogeneous and pinhole-free in the surface were observed. From obtained results, it is evident that deposits of ZnS–CBD using a non-toxic solution are suitable as window layer for TFSC.

  6. Sediment Origin Determination in the Sub-Catchment of Mistelbach (Austria) using Fatty Acids Biomarkers and Compound-Specific Stable Isotope Techniques

    International Nuclear Information System (INIS)

    Mabit, L.; Chen, X.; Resch, C.; Toloza, A.; Meusburger, K.; Alewell, C.; Gibbs, M.; Klik, A.; Eder, A.; Strauss, P.

    2016-01-01

    Compound-specific stable isotope (CSSI) signatures of inherent soil organic biomarkers allow discriminating and apportioning the source of soil contribution from different land uses. Plant communities label the soil where they grow by exuding organic biomarkers. Although all plants produce the same biomarkers, the stable isotopic signature of those biomarkers is different for each plant species. For agri-environmental investigations, the CSSI technique is based on the measurement of carbon-13 ( 13 C) natural abundance signatures of specific organic compounds such as natural fatty acids (FAs) in the soil. By linking fingerprints of land use to the sediment in deposition zones, this approach has been shown to be a useful technique for determining the source of eroded soil and thereby identifying areas prone to soil degradation. The authors have used this innovative technique to investigate a 3 hectares sub-catchment of Mistelbach situated 60 km north of Vienna. Using the 137 Cs technique, Mabit et al. (2009) reported a local maximum sedimentation rate reaching 20 to 50 t ha -1 yr -1 in the lowest part of this Austrian catchment. To test the ability of the CSSI technique to discriminate different sediment sources of these deposited sediments, representative soil samples from four main agricultural fields of the site were analyzed

  7. Minimally Adhesive, Advanced Non-toxic Coatings of Dendrimeric Catalysts in Sol-Gel Matrices

    Science.gov (United States)

    2015-10-19

    Catalysts in Sol -Gel Matrices 5a. CONTRACT NUMBER 5b. GRANT NUMBER N00014-09-1-0217 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Detty, Michael R. 5d...Technical Report for ONR N00014-09-1-0217 Minimally Adhesive, Advanced Non-toxic Coatings of Dendrimeric Catalysts in Sol -Gel Matrices Michael R. Detty, PI...Environmentally benign sol -gel antifouling and foul-releasing coatings. Ace. Chem. Res. 2014, 47, 678-687. 11) Alberto, E. E.; Müller, L. M

  8. Erbium Salts as Non-Toxic Catalysts Compatible with Alternative Reaction Media

    Directory of Open Access Journals (Sweden)

    Manuela Oliverio

    2018-03-01

    Full Text Available Green catalysts must be non-toxic, easy to manage, able to be recovered and reused, active under alternative reaction conditions and cheap. Erbium salts meet all the previously listed characteristics and today they are emerging as a valuable catalytic solution to a number of organic transformations needing a Lewis acid catalyst in wet conditions or under alternative heating sources. This review aims to summarize the application of erbium salts in green organic transformations, with particular emphasis on their versatility under both homogeneous and heterogeneous conditions. The erbium salts’ role in bifunctional catalysis is also presented.

  9. ISOLATION AND PATHOGENICITY OF A POSSIBLE Pythium aphanidermatum IN Jatropha Curcas L. NON TOXIC

    Directory of Open Access Journals (Sweden)

    Ofelia Andrea Valdes Rodriguez

    2011-03-01

    A chromista, possible Pythium aphanidermatum, was isolated from severely damage seeds and seedlings recently started from Jatropha curcas L. non toxic seeds sown in the tropical area of Veracruz, Mexico. In order to study pathogenic Pythium aphanidermatum effects over pre-emergent and post-emergent stages, seeds and young seedlings were inoculated with the isolated pathogen, and the chromista showed possible pathogenic activity against pre-emergency and recently started post-emergency; however, statistically significant damaged was not found in older seedlings.   Â

  10. Non-Toxic Orbiter Maneuvering System (OMS) and Reaction Control System

    Science.gov (United States)

    Hurlbert, Eric A.; Nicholson, Leonard S. (Technical Monitor)

    1999-01-01

    NASA is pursuing the technology and advanced development of a non-toxic (NT) orbital maneuvering system (OMS) and reaction control system (RCS) for shuttle upgrades, RLV, and reusable first stages. The primary objectives of the shuttle upgrades program are improved safety, improved reliability, reduced operations time and cost, improved performance or capabilities, and commonality with future space exploration needs. Non-Toxic OMS/RCS offers advantages in each of these categories. A non-toxic OMS/RCS eliminates the ground hazards and the flight safety hazards of the toxic and corrosive propellants. The cost savings for ground operations are over $24M per year for 7 flights, and the savings increase with increasing flight rate up to $44M per year. The OMS/RCS serial processing time is reduced from 65 days to 13 days. The payload capability can be increased up to 5100 Ibms. The non-toxic OMS/RCS also provides improved space station reboost capability up to 20 nautical miles over the current toxic system of 14 nautical miles. A NT OMS/RCS represents a clear advancement in the SOA over MMH/NTO. Liquid oxygen and ethanol are clean burning, high-density propellants that provide a high degree of commonality with other spacecraft subsystems including life support, power, and thermal control, and with future human exploration and development of space missions. The simple and reliable pressure-fed design uses sub-cooled liquid oxygen at 250 to 350 psia, which allows a propellant to remain cryogenic for longer periods of time. The key technologies are thermal insulation and conditioning techniques are used to maintain the sub-cooling. Phase I successfully defined the system architecture, designed an integrated OMS/RCS propellant tank, analyzed the feed system, built and tested the 870 lbf RCS thrusters, and tested the 6000 lbf OMS engine. Phase 11 is currently being planned for the development and test of full-scale prototype of the system in 1999 and 2000

  11. Thermochemical stability of Li-Cu-O ternary compounds stable at room temperature analyzed by experimental and theoretical methods

    Energy Technology Data Exchange (ETDEWEB)

    Lepple, Maren [Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen (Germany). Inst. for Applied Materials - Applied Materials Physics; Technische Univ. Darmstadt (Germany). Eduard-Zintl-Inst. of Inorganic and Physical Chemistry; Rohrer, Jochen; Albe, Karsten [Technische Univ. Darmstadt (Germany). Fachgebiet Materialmodellierung; Adam, Robert; Rafaja, David [Technical Univ. Freiberg (Germany). Inst. of Materials Science; Cupid, Damian M. [Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen (Germany). Inst. for Applied Materials - Applied Materials Physics; Austrian Institute of Technology GmbH, Vienna (Austria). Center for Low-Emission Transport TECHbase; Seifert, Hans J. [Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen (Germany). Inst. for Applied Materials - Applied Materials Physics

    2017-11-15

    Compounds in the Li-Cu-O system are of technological interest due to their electrochemical properties which make them attractive as electrode materials, i.e., in future lithium ion batteries. In order to select promising compositions for such applications reliable thermochemical data are a prerequisite. Although various groups have investigated individual ternary phases using different experimental setups, up to now, no systematic study of all relevant phases is available in the literature. In this study, we combine drop solution calorimetry with density function theory calculations to systematically investigate the thermodynamic properties of ternary Li-Cu-O phases. In particular, we present a consistently determined set of enthalpies of formation, Gibbs energies and heat capacities for LiCuO, Li{sub 2}CuO{sub 2} and LiCu{sub 2}O{sub 2} and compare our results with existing literature.

  12. Evaluation of the key aroma compounds in beef and pork vegetable gravies a la chef by stable isotope dilution assays and aroma recombination experiments.

    Science.gov (United States)

    Christlbauer, Monika; Schieberle, Peter

    2011-12-28

    Although the aroma compounds of meat processed as such have been studied previously, data on complete homemade dishes containing beef and pork meat were scarcely studied. Recently, 38 odor-active compounds were characterized in beef and pork vegetable gravies using GC-olfactometry. In the present investigation, the most odor-active compounds were quantitated in a freshly prepared stewed beef vegetable gravy (BVG) as well as a stewed pork vegetable gravy (PVG) by means of stable isotope dilution assays. Calculation of odor activity values (OAVs; ratio of concentration to odor threshold) revealed 3-mercapto-2-methylpentan-1-ol, (E,E)-2,4-decadienal, (E,Z)-2,6-nonadienal, (E)-2-decenal, (E)-2-undecanal, and 3-hydroxy-4,5-dimethyl-2(5H)-furanone as the most potent odorants in both gravies. However, significantly different OAVs were found for 12-methyltridecanal, which was much higher in the BVG, whereas (E,Z)-2,4-decadienal showed a clearly higher OAV in the PVG. Aroma recombination experiments performed on the basis of the actual concentrations of the odorants in both gravies revealed a good similarity of the aromas of both model mixtures containing all odorants with OAVs > 1 with those of the original gravies.

  13. Compound-specific stable carbon isotopic composition of petroleum hydrocarbons as a tool for tracing the source of oil spills

    International Nuclear Information System (INIS)

    Li Yun; Xiong Yongqiang; Yang Wanying; Xie Yueliang; Li Siyuan; Sun Yongge

    2009-01-01

    With the increasing demand for and consumption of crude oils, oil spill accidents happen frequently during the transportation of crude oils and oil products, and the environmental hazard they pose has become increasingly serious in China. The exact identification of the source of spilled oil can act as forensic evidence in the investigation and handling of oil spill accidents. In this study, a weathering simulation experiment demonstrates that the mass loss of crude oils caused by short-term weathering mainly occurs within the first 24 h after a spill, and is dominated by the depletion of low-molecular weight hydrocarbons ( 18 n-alkanes). Short-term weathering has no significant effect on δ 13 C values of individual n-alkanes (C 12 -C 33 ), suggesting that a stable carbon isotope profile of n-alkanes can be a useful tool for tracing the source of an oil spill, particularly for weathered oils or those with a relatively low concentration or absence of sterane and terpane biomarkers

  14. Non-Toxic Dual Thrust Reaction Control Engine Development for On-Orbit APS Applications

    Science.gov (United States)

    Robinson, Philip J.; Veith, Eric M.

    2003-01-01

    A non-toxic dual thrust proof-of-concept demonstration engine was successfully tested at the Aerojet Sacramento facility under a technology contract sponsored by the National Aeronautics and Space Administration's (NASA) Marshall Space Flight Center (MSFC). The goals of the NASA MSFC contract (NAS8-01109) were to develop and expand the technical maturity of a non-toxic, on-orbit auxiliary propulsion system (APS) thruster under the Next Generation Launch Technology (NGLT) program. The demonstration engine utilized the existing Kistler K-1 870 lbf LOX/Ethanol orbital maneuvering engine ( O m ) coupled with some special test equipment (STE) that enabled engine operation at 870 lbf in the primary mode and 25 lbf in the vernier mode. Ambient testing in primary mode varied mixture ratio (MR) from 1.28 to 1.71 and chamber pressure (P(c) from 110 to 181 psia, and evaluated electrical pulse widths (EPW) of 0.080, 0.100 and 0.250 seconds. Altitude testing in vernier mode explored igniter and thruster pulsing characteristics, long duration steady state operation (greater than 420 sec) and the impact of varying the percent fuel film cooling on vernier performance and chamber thermal response at low PC (4 psia). Data produced from the testing provided calibration of the performance and thermal models used in the design of the next version of the dual thrust Reaction Control Engine (RCE).

  15. Evaluation of the performance of high temperature conversion reactors for compound-specific oxygen stable isotope analysis.

    Science.gov (United States)

    Hitzfeld, Kristina L; Gehre, Matthias; Richnow, Hans-Hermann

    2017-05-01

    In this study conversion conditions for oxygen gas chromatography high temperature conversion (HTC) isotope ratio mass spectrometry (IRMS) are characterised using qualitative mass spectrometry (IonTrap). It is shown that physical and chemical properties of a given reactor design impact HTC and thus the ability to accurately measure oxygen isotope ratios. Commercially available and custom-built tube-in-tube reactors were used to elucidate (i) by-product formation (carbon dioxide, water, small organic molecules), (ii) 2nd sources of oxygen (leakage, metal oxides, ceramic material), and (iii) required reactor conditions (conditioning, reduction, stability). The suitability of the available HTC approach for compound-specific isotope analysis of oxygen in volatile organic molecules like methyl tert-butyl ether is assessed. Main problems impeding accurate analysis are non-quantitative HTC and significant carbon dioxide by-product formation. An evaluation strategy combining mass spectrometric analysis of HTC products and IRMS 18 O/ 16 O monitoring for future method development is proposed.

  16. The CSSIAR v.1.00 Software: A new tool based on SIAR to assess soil redistribution using Compound Specific Stable Isotopes

    Directory of Open Access Journals (Sweden)

    de los Santos-Villalobos Sergio

    2017-01-01

    Full Text Available Soil erosion is one of the biggest challenges for food production around the world. Many techniques have been used to evaluate and mitigate soil degradation. Nowadays isotopic techniques are becoming a powerful tool to assess soil apportionment. One of the innovative techniques used is the Compound Specific Stable Isotopes (CSSI analysis, which has been used to track down sediments and specify their sources by the isotopic signature of δ13C in specific fatty acids. The application of this technique on soil apportionment has been recently developed, however there is a lack of user-friendly Software for data processing and interpretation. The aim of this article is to introduce a new open source tool for working with data sets generated by the use of the CSSI technique to assess soil apportionment, called the CSSIARv1.00 Software

  17. Relationship between tolerance factor and temperature coefficient of permittivity of temperature-stable high permittivity BaTiO3–Bi(MeO3 compounds

    Directory of Open Access Journals (Sweden)

    Natthaphon Raengthon

    2016-03-01

    Full Text Available The temperature coefficient of permittivity (TCε of BaTiO3–Bi(MeO3 solid solutions were investigated. It was determined that as the tolerance factor was decreased with the addition of Bi(MeO3, the TCε shifted from large negative values to TCε values approaching zero. It is proposed that the different bonding nature of the dopant cation affects the magnitude and temperature stability of the permittivity. This study suggests that the relationship between tolerance factor and TCε can be used as a guide to design new dielectric compounds exhibiting temperature-stable high permittivity characteristics, which is similar to past research on perovskite and pyrochlore-based microwave dielectrics.

  18. The CSSIAR v.1.00 Software: A new tool based on SIAR to assess soil redistribution using Compound Specific Stable Isotopes

    Science.gov (United States)

    Sergio, de los Santos-Villalobos; Claudio, Bravo-Linares; dos Anjos Roberto, Meigikos; Renan, Cardoso; Max, Gibbs; Andrew, Swales; Lionel, Mabit; Gerd, Dercon

    Soil erosion is one of the biggest challenges for food production around the world. Many techniques have been used to evaluate and mitigate soil degradation. Nowadays isotopic techniques are becoming a powerful tool to assess soil apportionment. One of the innovative techniques used is the Compound Specific Stable Isotopes (CSSI) analysis, which has been used to track down sediments and specify their sources by the isotopic signature of δ13 C in specific fatty acids. The application of this technique on soil apportionment has been recently developed, however there is a lack of user-friendly Software for data processing and interpretation. The aim of this article is to introduce a new open source tool for working with data sets generated by the use of the CSSI technique to assess soil apportionment, called the CSSIARv1.00 Software

  19. Holocene Paleohydrological Changes in Northern Michigan: Interpretations of Biomarker Distributions and Compound Specific Stable Isotope Analysis from Peatlands

    Science.gov (United States)

    Nichols, J. E.; Booth, R. K.; Jackson, S. T.; Pendall, E. G.; Huang, Y.

    2006-12-01

    Sediments of ombrotrophic peatlands are excellent archives for reconstructing past changes in precipitation/evaporation (P/E) balance. Multiproxy analysis of these sediments is critical for better understanding of climatic events experienced by these highly sensitive systems, as each proxy may respond to different climate parameters. In this study, we use distributions of n-alkanes and δD of Sphagnum biomarkers to interpret paleohydrology from sediments of Irwin Smith Bog, northern Michigan. We then integrate these data with pollen data and testate amoebae-inferred water table depth. Sphagnum moss is the dominant peat former in ombrotrophic bogs, but vascular plants become abundant when water tables are drawn down. Thus, the abundance of Sphagnum relative to vascular plants is indicative of peatland hydrology. The n-alkanes produced by Sphagnum differ from vascular plants in the relative abundance of the different homologues, with the former having excess amounts of shorter chain C23 n-alkane. We use several measures (compound ratios, PCA) to show changes in then-alkane distributions in the sediments, and thus changes in the peatland plant community. Our data provide high- resolution, quantitative paleohydrological records for the study region that are consistent with other records. We also show that the relative abundance of a newly identified Sphagnum biomarker, 2-heptacosanone, can be used to reconstruct changing plant communities. Because ombrotrophic systems lose water by evaporation, drier/warmer conditions cause hydrogen isotopic enrichment of bog water and Sphagnum biomarkers. We measured the δD of C23 n-alkane and 2-heptacosanone to provide additional paleoclimate information. Our multiproxy approach allows us to better understand the climate changes during key intervals of the Holocene. For example, a sharp decrease in the abundance of Tsuga canadensis (hemlock) pollen has been previously identified in records from many places throughout eastern North

  20. Sources of variability in fatty acid (FA) biomarkers in the application of compound-specific stable isotopes (CSSIs) to soil and sediment fingerprinting and tracing: A review

    Energy Technology Data Exchange (ETDEWEB)

    Reiffarth, D.G., E-mail: Dominic.Reiffarth@unbc.ca [Natural Resources and Environmental Studies Program, University of Northern British Columbia, 3333 University Way, Prince George, BC V2N 4Z9 (Canada); Petticrew, E.L., E-mail: Ellen.Petticrew@unbc.ca [Geography Program and Quesnel River Research Centre, University of Northern British Columbia, 3333 University Way, Prince George, BC V2N 4Z9 (Canada); Owens, P.N., E-mail: Philip.Owens@unbc.ca [Environmental Science Program and Quesnel River Research Centre, University of Northern British Columbia, 3333 University Way, Prince George, BC, V2N 4Z9 (Canada); Lobb, D.A., E-mail: David.Lobb@umanitoba.ca [Watershed Systems Research Program, University of Manitoba, 13 Freedman Crescent, Winnipeg, MB R3T 2N2 (Canada)

    2016-09-15

    Determining soil redistribution and sediment budgets in watersheds is often challenging. One of the methods for making such determinations employs soil and sediment fingerprinting techniques, using sediment properties such as geochemistry, fallout radionuclides, and mineral magnetism. These methods greatly improve the estimation of erosion and deposition within a watershed, but are limited when determining land use-based soil and sediment movement. Recently, compound-specific stable isotopes (CSSIs), which employ fatty acids naturally occurring in the vegetative cover of soils, offer the possibility of refining fingerprinting techniques based on land use, complementing other methods that are currently in use. The CSSI method has been met with some success; however, challenges still remain with respect to scale and resolution due to a potentially large degree of biological, environmental and analytical uncertainty. By better understanding the source of tracers used in CSSI work and the inherent biochemical variability in those tracers, improvement in sample design and tracer selection is possible. Furthermore, an understanding of environmental and analytical factors affecting the CSSI signal will lead to refinement of the approach and the ability to generate more robust data. This review focuses on sources of biological, environmental and analytical variability in applying CSSI to soil and sediment fingerprinting, and presents recommendations based on past work and current research in this area for improving the CSSI technique. A recommendation, based on current information available in the literature, is to use very-long chain saturated fatty acids and to avoid the use of the ubiquitous saturated fatty acids, C{sub 16} and C{sub 18}. - Highlights: • Compound-specific stable isotopes (CSSIs) of carbon may be used as soil tracers. • The variables affecting CSSI data are: biological, environmental and analytical. • Understanding sources of variability will lead

  1. Sources of variability in fatty acid (FA) biomarkers in the application of compound-specific stable isotopes (CSSIs) to soil and sediment fingerprinting and tracing: A review

    International Nuclear Information System (INIS)

    Reiffarth, D.G.; Petticrew, E.L.; Owens, P.N.; Lobb, D.A.

    2016-01-01

    Determining soil redistribution and sediment budgets in watersheds is often challenging. One of the methods for making such determinations employs soil and sediment fingerprinting techniques, using sediment properties such as geochemistry, fallout radionuclides, and mineral magnetism. These methods greatly improve the estimation of erosion and deposition within a watershed, but are limited when determining land use-based soil and sediment movement. Recently, compound-specific stable isotopes (CSSIs), which employ fatty acids naturally occurring in the vegetative cover of soils, offer the possibility of refining fingerprinting techniques based on land use, complementing other methods that are currently in use. The CSSI method has been met with some success; however, challenges still remain with respect to scale and resolution due to a potentially large degree of biological, environmental and analytical uncertainty. By better understanding the source of tracers used in CSSI work and the inherent biochemical variability in those tracers, improvement in sample design and tracer selection is possible. Furthermore, an understanding of environmental and analytical factors affecting the CSSI signal will lead to refinement of the approach and the ability to generate more robust data. This review focuses on sources of biological, environmental and analytical variability in applying CSSI to soil and sediment fingerprinting, and presents recommendations based on past work and current research in this area for improving the CSSI technique. A recommendation, based on current information available in the literature, is to use very-long chain saturated fatty acids and to avoid the use of the ubiquitous saturated fatty acids, C 16 and C 18 . - Highlights: • Compound-specific stable isotopes (CSSIs) of carbon may be used as soil tracers. • The variables affecting CSSI data are: biological, environmental and analytical. • Understanding sources of variability will lead to more

  2. Test Results for a Non-toxic, Dual Thrust Reaction Control Engine

    Science.gov (United States)

    Robinson, Philip J.; Veith, Eric M.; Turpin, Alicia A.

    2005-01-01

    A non-toxic, dual thrust reaction control engine (RCE) was successfully tested over a broad range of operating conditions at the Aerojet Sacramento facility. The RCE utilized LOX/Ethanol propellants; and was tested in steady state and pulsing modes at 25-lbf thrust (vernier) and at 870-lbf thrust (primary). Steady state vernier tests vaned chamber pressure (Pc) from 0.78 to 5.96 psia, and mixture ratio (MR) from 0.73 to 1.82, while primary steady state tests vaned Pc from 103 to 179 psia and MR from 1.33 to 1.76. Pulsing tests explored EPW from 0.080 to 10 seconds and DC from 5 to 50 percent at both thrust levels. Vernier testing accumulated a total of 6,670 seconds of firing time, and 7,215 pulses, and primary testing accumulated a total of 2,060 seconds of firing time and 3,646 pulses.

  3. Enrichment of Cellulosic Waste Hemp (Cannabis sativa Hurd into Non-Toxic Microfibres

    Directory of Open Access Journals (Sweden)

    Reinu E. Abraham

    2016-07-01

    Full Text Available In this study a largely available lignocellulose feedstock hemp (Cannabis sativa, obtained as an industrial waste, was used for cellulose extraction. The extraction of cellulose microfibres from hemp biomass was conducted by alkaline treatment and an acidification process. The extracted cellulose microfibres were characterised using Fourier-transformed infrared spectroscopy (FTIR, Scanning electron microscopy (SEM, thermogravimetric analysis (TGA and X-ray diffraction (XRD. The viability of the study was determined by growing human fibroblasts on the preparation which resulted in being non-toxic; indicating its potential in preparing biological scaffolds. Upon enzymatic hydrolysis of the cellulose microfibre using cellulase from Trichoderma reesei, a maximum of 909 mg/g of reducing sugars were obtained, which endorses its suitability for biofuel production.

  4. Crystal structure of a catalytically active, non-toxic endopeptidase derivative of Clostridium botulinum toxin A.

    Science.gov (United States)

    Masuyer, Geoffrey; Thiyagarajan, Nethaji; James, Peter L; Marks, Philip M H; Chaddock, John A; Acharya, K Ravi

    2009-03-27

    Botulinum neurotoxins (BoNTs) modulate cholinergic nerve terminals to result in neurotransmitter blockade. BoNTs consists of catalytic (LC), translocation (Hn) and cell-binding domains (Hc). The binding function of the Hc domain is essential for BoNTs to bind the neuronal cell membrane, therefore, removal of the Hc domain results in a product that retains the endopeptidase activity of the LC but is non-toxic. Thus, a molecule consisting of LC and Hn domains of BoNTs, termed LHn, is a suitable molecule for engineering novel therapeutics. The structure of LHA at 2.6 A reported here provides an understanding of the structural implications and challenges of engineering therapeutic molecules that combine functional properties of LHn of BoNTs with specific ligand partners to target different cell types.

  5. A protocol for pressurized liquid extraction and processing methods to isolate modern and ancient bone cholesterol for compound-specific stable isotope analysis.

    Science.gov (United States)

    Laffey, Ann O; Krigbaum, John; Zimmerman, Andrew R

    2017-02-15

    Bone lipid compound-specific isotope analysis (CSIA) and bone collagen and apatite stable isotope ratio analysis are important sources of ecological and paleodietary information. Pressurized liquid extraction (PLE) is quicker and utilizes less solvent than traditional methods of lipid extraction such as soxhlet and ultrasonication. This study facilitates dietary analysis by optimizing and testing a standardized methodology for PLE of bone cholesterol. Modern and archaeological bones were extracted by PLE using varied temperatures, solvent solutions, and sample weights. The efficiency of PLE was assessed via quantification of cholesterol yields. Stable isotopic ratio integrity was evaluated by comparing isotopic signatures (δ 13 C and δ 18 O values) of cholesterol derived from whole bone, bone collagen and bone apatite. Gas chromatography/mass spectrometry (GC/MS) and gas chromatography isotope ratio mass spectrometry (GC/IRMS) were conducted on purified collagen and lipid extracts to assess isotopic responses to PLE. Lipid yield was optimized at two PLE extraction cycles of 75 °C using dichloromethane/methanol (2:1 v/v) as a solvent with 0.25-0.75 g bone sample. Following lipid extraction, saponification combined with the derivatization of the neutral fraction using trimethylsilylation yielded nearly twice the cholesterol of non-saponified or non-derivatized samples. It was also found that lipids extracted from purified bone collagen and apatite could be used for cholesterol CSIA. There was no difference in the bulk δ 13 C values of collagen extracted from bone with or without lipid. However, there was a significant depletion in 18 O of bone apatite due to lipid presence or processing. These results should assist sample selection and provide an effective, alternative extraction method for bone cholesterol that may be used for isotopic and paleodietary analysis. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  6. Molecularly imprinted solid phase extraction using stable isotope labeled compounds as template and liquid chromatography-mass spectrometry for trace analysis of bisphenol A in water sample

    International Nuclear Information System (INIS)

    Kawaguchi, Migaku; Hayatsu, Yoshio; Nakata, Hisao; Ishii, Yumiko; Ito, Rie; Saito, Koichi; Nakazawa, Hiroyuki

    2005-01-01

    We have developed a molecularly imprinted polymer (MIP) using a stable isotope labeled compound as the template molecule and called it the ''isotope molecularly imprinted polymer'' (IMIP). In this study, bisphenol A (BPA) was used as the model compound. None imprinted polymer (NIP), MIP, dummy molecularly imprinted polymer (DMIP) and IMIP were prepared by the suspension polymerization method using without template, BPA, 4-tert-butylphenol (BP) and bisphenol A-d 16 (BPA-d 16 ), respectively. The polymers were subjected to molecularly imprinted solid phase extraction (MI-SPE), and the extracted samples were subjected to liquid chromatography-mass spectrometry (LC-MS). Although the leakage of BPA-d 16 from the IMIP was observed and that of BPA was not observed. The selectivity factors of MIP and IMIP for BPA were 4.45 and 4.43, respectively. Therefore, IMIP had the same molecular recognition ability as MIP. When MI-SPE with IMIP was used and followed by LC-MS in the analysis of river water sample, the detection limit of BPA was 1 ppt with high sensitivity. Moreover, the average recovery was higher than 99.8% (R.S.D.: 3.7%) by using bisphenol A- 13 C 12 (BPA- 13 C 12 ) as the surrogate standard. In addition, the IMIP were employed in MI-SPE of BPA in river water sample by LC-MS. The concentration of BPA in the river water sample was determined to be 32 pg ml -1 . We confirmed that it was possible to measure trace amounts of a target analyte by MI-SPE using IMIP

  7. Study on the metabolism of physiological amounts of Cr(III) intragastrical administration in normal rats using activable enriched stable isotope Cr-50 compound as a tracer

    International Nuclear Information System (INIS)

    Feng, W.Y.; Ding, W.J.; Qian, Q.F.; Chai, Z.F.

    1998-01-01

    In order to study the metabolism of physiological amounts of 51 Cr (10μg/100 g of body wt.) intragastrically administered in rats, the activable enriched stable isotope Cr-50 compound Cr 2 O 3 was used as a tracer. The absorption and distribution of 51 Cr(III) in rats with time were studied. Significant 51 Cr contents were found in all the organs and tissues of interest. The kidney, liver and bone contain higher amounts of 51 Cr than others. The fact that specific activities of 51 Cr are notably high in kidney, bone, spleen and pancreas and decrease gradually with time suggests that there are tighter binding of chromium in these organs. The excretion of 51 Cr at various time intervals was also studied. Almost totally intragastrically administered dose was excreted in the feces. The increased urinary excretion of 51 Cr with time indicates that the urine-chromium is the metabolic derivative of organism. In view of the tissues distribution and excretion, it can be concluded that no more than 1% of the dose was absorbed from the gastrointestinal tract. (author)

  8. Comparative gene expression in toxic versus non-toxic strains of the marine dinoflagellate Alexandrium minutum

    Directory of Open Access Journals (Sweden)

    Glöckner Gernot

    2010-04-01

    Full Text Available Abstract Background The dinoflagellate Alexandrium minutum typically produces paralytic shellfish poisoning (PSP toxins, which are known only from cyanobacteria and dinoflagellates. While a PSP toxin gene cluster has recently been characterized in cyanobacteria, the genetic background of PSP toxin production in dinoflagellates remains elusive. Results We constructed and analysed an expressed sequence tag (EST library of A. minutum, which contained 15,703 read sequences yielding a total of 4,320 unique expressed clusters. Of these clusters, 72% combined the forward-and reverse reads of at least one bacterial clone. This sequence resource was then used to construct an oligonucleotide microarray. We analysed the expression of all clusters in three different strains. While the cyanobacterial PSP toxin genes were not found among the A. minutum sequences, 192 genes were differentially expressed between toxic and non-toxic strains. Conclusions Based on this study and on the lack of identified PSP synthesis genes in the two existent Alexandrium tamarense EST libraries, we propose that the PSP toxin genes in dinoflagellates might be more different from their cyanobacterial counterparts than would be expected in the case of a recent gene transfer. As a starting point to identify possible PSP toxin-associated genes in dinoflagellates without relying on a priori sequence information, the sequences only present in mRNA pools of the toxic strain can be seen as putative candidates involved in toxin synthesis and regulation, or acclimation to intracellular PSP toxins.

  9. Plasma deposition of cubic boron nitride films from non-toxic material at low temperatures

    International Nuclear Information System (INIS)

    Karim, M.Z.; Cameron, D.C.; Murphy, M.J.; Hashmi, M.S.J.

    1991-01-01

    Boron nitride has become the focus of a considerable amount of interest because of its properties which relate closely to those of carbon. In particular, the cubic nitride phase has extreme hardness and very high thermal conductivity similar to the properties of diamond. The conventional methods of synthesis use the highly toxic and inflammable gas diborane (B 2 H 6 ) as the reactant material. A study has been made of the deposition of thin films of boron nitride (BN) using non-toxic material by the plasma-assisted chemical vapour deposition technique. The source material was borane-ammonia (BH 3 -NH 3 ) which is a crystalline solid at room temperature with a high vapour pressure. The BH 3 -NH 3 vapour was decomposed in a 13.56 MHz nitrogen plasma coupled either inductively or capacitively with the system. The composition of the films was assessed by measuring their IR absorption when deposited on silicon and KBr substrates. The hexagonal (graphitic) and cubic (diamond-like) allotropes can be distinguished by their characteristic absorption bands which occur at 1365 and 780 cm -1 (hexagonal) and 1070 cm -1 (cubic). We have deposited BN films consisting of a mixture of hexagonal and cubic phases; the relative content of the cubic phase was found to be directly dependent on r.f. power and substrate bias. (orig.)

  10. XeBr excilamp based on a non-toxic component mixture

    Energy Technology Data Exchange (ETDEWEB)

    Kelman, V A; Shpenik, Yu O; Zhmenyak, Yu V, E-mail: mironkle@rambler.ru [Institute of Electron Physics, National Academy of Sciences of Ukraine, Universitetska 21, 88017 Uzhgorod (Ukraine)

    2011-06-29

    This paper presents the results of experimental studies on obtaining UV luminescence of XeBr* molecules at the excitation of a non-toxic Xe-CsBr gas-vapour mixture by a longitudinal pulse-periodic discharge. Effective UV emission yield of the exciplex XeBr* molecules (spectral maximum at 282 nm) is observed within a wide range of excitation conditions. The spectral distribution in the UV emission under the optimal excitation conditions does not differ essentially from that in other XeBr excilamps based on toxic components. The emission of the B {yields} X band of the XeBr* molecules provides the main contribution to the total power of the discharge UV emission. The determined average power of the UV emission for the experimental discharge tube is 12 W at an efficiency of 1%. Spectral, power-related and time-dependent parameters of the laboratory excilamp are presented for a wide range of excitation parameters. A new mechanism of exciplex molecule formation at the excitation of a rare gas/alkali halide vapour mixture is discussed.

  11. XeBr excilamp based on a non-toxic component mixture

    International Nuclear Information System (INIS)

    Kelman, V A; Shpenik, Yu O; Zhmenyak, Yu V

    2011-01-01

    This paper presents the results of experimental studies on obtaining UV luminescence of XeBr* molecules at the excitation of a non-toxic Xe-CsBr gas-vapour mixture by a longitudinal pulse-periodic discharge. Effective UV emission yield of the exciplex XeBr* molecules (spectral maximum at 282 nm) is observed within a wide range of excitation conditions. The spectral distribution in the UV emission under the optimal excitation conditions does not differ essentially from that in other XeBr excilamps based on toxic components. The emission of the B → X band of the XeBr* molecules provides the main contribution to the total power of the discharge UV emission. The determined average power of the UV emission for the experimental discharge tube is 12 W at an efficiency of 1%. Spectral, power-related and time-dependent parameters of the laboratory excilamp are presented for a wide range of excitation parameters. A new mechanism of exciplex molecule formation at the excitation of a rare gas/alkali halide vapour mixture is discussed.

  12. Remediation of lead-contaminated soil with non-toxic biodegradable natural ligands extracted from soybean.

    Science.gov (United States)

    Lee, Yong-Woo; Kim, Chulsung

    2012-01-01

    Bench-scale soil washing studies were performed to evaluate the potential application of non-toxic, biodegradable extracted soybean-complexing ligands for the remediation of lead-contaminated soils. Results showed that, with extracted soybean-complexing ligands, lead solubility extensively increased when pH of the solution was higher than 6, and approximately 10% (500 mg/kg) of lead was removed from a rifle range soil. Two potential primary factors controlling the effectiveness of lead extraction from lead-contaminated soils with natural ligands are adsorption of extracted aqueous lead ions onto the ground soybean and the pH of the extraction solution. More complexing ligands were extracted from the ground soybean as the reaction pH increased. As a result, significantly higher lead extraction efficiency was observed under basic environments. In addition, less adsorption onto soybean was observed when the pH of the solution was higher than 7. Among two available Lewis base functional groups in the extracted soybean-complexing ligands such as carboxylate and the alpha-amino functional groups, the non-protonated alpha-amino functional groups may play an important role for the dissolution of lead from lead-contaminated soil through the formation of soluble lead--ligand complexes.

  13. The production of hydrotalcite from magnesite ore as non-toxic heat stabiliser for polyvinyl chloride

    Directory of Open Access Journals (Sweden)

    J. van der Laan

    2005-09-01

    Full Text Available In recent years polyvinyl chloride (PVC processors had to submit to worldwide pressure to convert to environmentally friendly stabilisers such as hydrotalcite (HT, since most of the heat stabilisers currently in use contain heavy metals such as lead, cadmium or barium – these being highly toxic. The presently used HT production process is, however, very expensive as it involves the recovering of magnesium from seawater magnesia. The purpose of this study was to prove that it is indeed possible to produce cost effective and non-toxic HT from an alternative source. During this study the costing and heat stabilising ability of the hydrotalcite produced from magnesite was compared to that of commercially available heat stabilisers. The effect of the pre-mixing process, as well as the influence of particle size distribution was also investigated. A cost comparative and stabilising efficiency study indicated the cost effectiveness of HT produced from magnesite ore, in comparison with other commercially available stabilisers. The use of HT as produced from magnesite ore would indeed assist in the worldwide changeover to environmentally friendly stabilisers.

  14. Machine learning can differentiate venom toxins from other proteins having non-toxic physiological functions

    Directory of Open Access Journals (Sweden)

    Ranko Gacesa

    2016-10-01

    Full Text Available Ascribing function to sequence in the absence of biological data is an ongoing challenge in bioinformatics. Differentiating the toxins of venomous animals from homologues having other physiological functions is particularly problematic as there are no universally accepted methods by which to attribute toxin function using sequence data alone. Bioinformatics tools that do exist are difficult to implement for researchers with little bioinformatics training. Here we announce a machine learning tool called ‘ToxClassifier’ that enables simple and consistent discrimination of toxins from non-toxin sequences with >99% accuracy and compare it to commonly used toxin annotation methods. ‘ToxClassifer’ also reports the best-hit annotation allowing placement of a toxin into the most appropriate toxin protein family, or relates it to a non-toxic protein having the closest homology, giving enhanced curation of existing biological databases and new venomics projects. ‘ToxClassifier’ is available for free, either to download (https://github.com/rgacesa/ToxClassifier or to use on a web-based server (http://bioserv7.bioinfo.pbf.hr/ToxClassifier/.

  15. Comparison of starch and gelatin hydrogels for non-toxic supercapacitor electrolytes

    Science.gov (United States)

    Railanmaa, Anna; Lehtimäki, Suvi; Lupo, Donald

    2017-06-01

    Starch and gelatin are two of the most abundantly available natural polymers. Their non-toxicity, low cost, and compatibility with aqueous solvents make them ideal for use in ubiquitous, environmentally friendly electronics systems. This work presents the results of conductivity measurements through impedance spectroscopy for gelatin- and starch-based aqueous gel electrolytes. The NaCl-based gels were physically cross-linked. The conductivity values were 84.6 mS/cm at 1.5 mol L-1 and 71.5 mS/cm at 2 mol L-1 for gelatin and starch, respectively. The mechanical properties of gelatin were found preferable to those of starch, although they deteriorated significantly when the salt concentration exceeded 2 mol L-1. The ability of the gels to successfully act as a supercapacitor electrolyte was demonstrated with printed electrodes on plastic substrate. The devices were characterized through cyclic voltammetry measurements. The results imply that these polymer gel electrolytes are very promising for replacing the traditional aqueous liquid electrolytes in supercapacitors in applications where, for example, user and environmental safety is essential.

  16. In vitro regeneration from petiole explants of non-toxic Jatropha curcas

    KAUST Repository

    Kumar, Nitish

    2011-01-01

    Jatropha curcas, a multipurpose shrub has acquired significant economic potential as biodiesel plant. The seeds or pressed cake is toxic due to the presence of toxic substances and is not useful as food/fodder despite having the best protein composition. A simple, efficient, and reproducible method for plant regeneration through direct organogenesis from petiole explants of non-toxic J. curcas was developed using Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ). The best induction of shoot buds (57.61%), and number of shoot buds (4.98) per explant were obtained when in vitro petiole explants were placed horizontally on MS medium supplemented with 2.27 mu M TDZ. The Induced shoot buds were transferred to MS medium containing 10 mu M kinetin (Kn), 4.5 mu M 6-benzyl aminopurine (BA), and 5.5 mu M alpha-naphthaleneacetic acid (NAA) for shoot proliferation and subsequent elongation was achieved on MS medium supplemented with 2.25 mu M BA and 8.5 mu M IAA. The elongated shoots could be rooted on half-strength MS medium with 15 mu M IBA, 11.4 mu M IAA and 5.5 mu M NAA with more than 90% survival rate. (C) 2010 Elsevier B.V. All rights reserved.

  17. Non-toxic silver iodide (AgI) quantum dots sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Moosakhani, S. [Faculty of Polymer Engineering and Color Technology, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Color and Polymer Research Center (CPRC), Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Sabbagh Alvani, A.A., E-mail: sabbagh_alvani@aut.ac.ir [Color and Polymer Research Center (CPRC), Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Sarabi, A.A. [Faculty of Polymer Engineering and Color Technology, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Sameie, H.; Salimi, R.; Kiani, S.; Ebrahimi, Y. [Faculty of Polymer Engineering and Color Technology, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Color and Polymer Research Center (CPRC), Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of)

    2014-12-15

    Highlights: • We have demonstrated AgI sensitized solar cell for the first time. • Obtained mesoporous titania powders possessed small crystallite size, high purity and surface area, and developed mesopores with a narrow pore size distribution. • Photovoltaic measurements revealed the electron injection from AgI to TiO{sub 2}. • The assembled AgI-QD solar cells yielded a power conversion efficiency of 0.64% under one sun illumination. • AgI may be a suitable candidate material for use as a non-toxic sensitizer in QDSSC. - Abstract: The present study reports the performance of a new photosensitizer -AgI quantum dots (QDs)- and mesoporous titania (TiO{sub 2}) nanocrystals synthesized by sol–gel (SG) method for solar cells. Furthermore, the effects of n-heptane on the textural properties of TiO{sub 2} nanocrystals were comprehensively investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), N{sub 2} adsorption–desorption measurements, and UV–vis spectroscopy. TiO{sub 2} powders exhibited an anatase-type mesoporous structure with a high surface area of 89.7 m{sup 2}/g. Afterwards, the QDs were grown on mesoporous TiO{sub 2} surface to fabricate a TiO{sub 2}/AgI electrode by a successive ionic layer adsorption and reaction (SILAR) deposition route. Current–voltage characteristics and electrochemical impedance spectroscopy (EIS) data demonstrated that the injection of photoexcited electrons from AgI QDs into the TiO{sub 2} matrix produces photocurrents. The assembled AgI-QD solar cells yielded a power conversion efficiency of 0.64% and a short-circuit current of 2.13 mA/cm{sup 2} under one sun illumination.

  18. Non-toxic silver iodide (AgI) quantum dots sensitized solar cells

    International Nuclear Information System (INIS)

    Moosakhani, S.; Sabbagh Alvani, A.A.; Sarabi, A.A.; Sameie, H.; Salimi, R.; Kiani, S.; Ebrahimi, Y.

    2014-01-01

    Highlights: • We have demonstrated AgI sensitized solar cell for the first time. • Obtained mesoporous titania powders possessed small crystallite size, high purity and surface area, and developed mesopores with a narrow pore size distribution. • Photovoltaic measurements revealed the electron injection from AgI to TiO 2 . • The assembled AgI-QD solar cells yielded a power conversion efficiency of 0.64% under one sun illumination. • AgI may be a suitable candidate material for use as a non-toxic sensitizer in QDSSC. - Abstract: The present study reports the performance of a new photosensitizer -AgI quantum dots (QDs)- and mesoporous titania (TiO 2 ) nanocrystals synthesized by sol–gel (SG) method for solar cells. Furthermore, the effects of n-heptane on the textural properties of TiO 2 nanocrystals were comprehensively investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), N 2 adsorption–desorption measurements, and UV–vis spectroscopy. TiO 2 powders exhibited an anatase-type mesoporous structure with a high surface area of 89.7 m 2 /g. Afterwards, the QDs were grown on mesoporous TiO 2 surface to fabricate a TiO 2 /AgI electrode by a successive ionic layer adsorption and reaction (SILAR) deposition route. Current–voltage characteristics and electrochemical impedance spectroscopy (EIS) data demonstrated that the injection of photoexcited electrons from AgI QDs into the TiO 2 matrix produces photocurrents. The assembled AgI-QD solar cells yielded a power conversion efficiency of 0.64% and a short-circuit current of 2.13 mA/cm 2 under one sun illumination

  19. Triple-element compound-specific stable isotope analysis of 1,2-dichloroethane for characterization of the underlying dehalogenation reaction in two Dehalococcoides mccartyi strains.

    Science.gov (United States)

    Franke, Steffi; Lihl, Christina; Renpenning, Julian; Elsner, Martin; Nijenhuis, Ivonne

    2017-12-01

    Chlorinated ethanes belong to the most common groundwater and soil contaminants. Of these, 1,2-dichloroethane (1,2-DCA) is a man-made, persistent and toxic contaminant, released due to improper waste treatment at versatile production sites. This study investigated the anaerobic transformation of 1,2-DCA by Dehalococcoides mccartyi strain 195 and strain BTF08 using triple-element compound-specific stable isotope analysis of carbon, chlorine and hydrogen for the first time. Isotope fractionation patterns for carbon (εCBTF08 = -28.4 ± 3.7‰; εC195 = -30.9 ± 3.6‰) and chlorine (εClBTF08 = -4.6 ± 0.7‰; εCl195 = -4.2 ± 0.5‰) within both investigated D. mccartyi strains, as well as the dual-element analysis (ΛBTF08 = 6.9 ± 1.2; Λ195 = 7.1 ± 0.2), supported identical reaction mechanisms for dehalogenation of 1,2-DCA. Hydrogen isotope fractionation analysis revealed dihaloelimination as prevalent reaction mechanism. Vinyl chloride as major intermediate could be excluded by performing the experiment in deuterated aqueous media. Furthermore, evaluation of the derived apparent kinetic isotope effects (AKIECBTF08 = 1.029/AKIEC195 = 1.031; AKIEClBTF08 = 1.005/AKIECl195 = 1.004) pointed towards simultaneous abstraction of both involved chlorine-substituents in a concerted matter. It was shown that D. mccartyi strain BTF08 and strain 195 are capable of complete, direct dihaloelimination of 1,2-DCA to ethene. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Benzylic rearrangement stable isotope labeling for quantitation of guanidino and ureido compounds in thyroid tissues by liquid chromatography-electrospray ionization mass spectrometry

    International Nuclear Information System (INIS)

    Fan, Ruo-Jing; Guan, Qing; Zhang, Fang; Leng, Jia-Peng; Sun, Tuan-Qi; Guo, Yin-Long

    2016-01-01

    Benzylic rearrangement stable isotope labeling (BRSIL) was explored to quantify the guanidino and ureido compounds (GCs and UCs). This method employed a common reagent, benzil, to label the guanidino and ureido groups through nucleophilic attacking then benzylic migrating. The use of BRSIL was investigated in the analysis of five GCs (creatine, L-arginine, homoarginine, 4-guanidinobutyric acid, and methylguanidine) and two UCs (urea and citrulline). The labeling was found simple and specific. The introduction of bi-phenyl group and the generation of nitrogen heterocyclic ring in the benzil-d0/d5 labeled GCs and UCs improved the retention behaviors in liquid chromatography (LC) and increased the sensitivity of electrospray ionization mass spectrometry (ESI MS) detection. The fragment ion pairs of m/z 182/187 and m/z 210/215 from the benzil-d0/d5 tags facilitated the discovery of potential GCs and UCs candidates residing in biological matrices. The use of BRSIL combined with LC-ESI MS was applied for simultaneously quantitation of GCs and UCs in thyroid tissues. It was demonstrated that nine GCs and UCs were detected, six of which were further quantified based on corresponding standards. It was concluded that five GCs and UCs (L-arginine, homoarginine, 4-guanidinobutyric acid, methylguanidine, and citrulline) were statistically significantly different (p < 0.05) between the para-carcinoma and carcinoma thyroid tissue samples. - Highlights: • A common reagent, benzil-d0/d5 was employed to label the GCs and UCs through BRSIL. • The benzil-d0/d5 labeling improved the retention behavior in RPLC and increased the sensitivity by ESI MS detection. • BRSIL coupled with LC-ESI MS was applied to the qualitation and quantitation of GCs and UCs in thyroid tissues.

  1. Benzylic rearrangement stable isotope labeling for quantitation of guanidino and ureido compounds in thyroid tissues by liquid chromatography-electrospray ionization mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Ruo-Jing [State Key Laboratory of Organmetallic Chemistry and National Center for Organic Mass Spectrometry in Shanghai, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032 (China); Guan, Qing [Department of Head and Neck Surgery, Fudan University Shanghai Cancer Center, Shanghai, 200032 (China); Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032 (China); Zhang, Fang, E-mail: fzhang@sioc.ac.cn [State Key Laboratory of Organmetallic Chemistry and National Center for Organic Mass Spectrometry in Shanghai, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032 (China); Leng, Jia-Peng [State Key Laboratory of Organmetallic Chemistry and National Center for Organic Mass Spectrometry in Shanghai, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032 (China); Sun, Tuan-Qi, E-mail: tuanqisun@163.com [Department of Head and Neck Surgery, Fudan University Shanghai Cancer Center, Shanghai, 200032 (China); Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032 (China); Guo, Yin-Long, E-mail: ylguo@sioc.ac.cn [State Key Laboratory of Organmetallic Chemistry and National Center for Organic Mass Spectrometry in Shanghai, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032 (China)

    2016-02-18

    Benzylic rearrangement stable isotope labeling (BRSIL) was explored to quantify the guanidino and ureido compounds (GCs and UCs). This method employed a common reagent, benzil, to label the guanidino and ureido groups through nucleophilic attacking then benzylic migrating. The use of BRSIL was investigated in the analysis of five GCs (creatine, L-arginine, homoarginine, 4-guanidinobutyric acid, and methylguanidine) and two UCs (urea and citrulline). The labeling was found simple and specific. The introduction of bi-phenyl group and the generation of nitrogen heterocyclic ring in the benzil-d0/d5 labeled GCs and UCs improved the retention behaviors in liquid chromatography (LC) and increased the sensitivity of electrospray ionization mass spectrometry (ESI MS) detection. The fragment ion pairs of m/z 182/187 and m/z 210/215 from the benzil-d0/d5 tags facilitated the discovery of potential GCs and UCs candidates residing in biological matrices. The use of BRSIL combined with LC-ESI MS was applied for simultaneously quantitation of GCs and UCs in thyroid tissues. It was demonstrated that nine GCs and UCs were detected, six of which were further quantified based on corresponding standards. It was concluded that five GCs and UCs (L-arginine, homoarginine, 4-guanidinobutyric acid, methylguanidine, and citrulline) were statistically significantly different (p < 0.05) between the para-carcinoma and carcinoma thyroid tissue samples. - Highlights: • A common reagent, benzil-d0/d5 was employed to label the GCs and UCs through BRSIL. • The benzil-d0/d5 labeling improved the retention behavior in RPLC and increased the sensitivity by ESI MS detection. • BRSIL coupled with LC-ESI MS was applied to the qualitation and quantitation of GCs and UCs in thyroid tissues.

  2. First use of a compound-specific stable isotope (CSSI) technique to trace sediment transport in upland forest catchments of Chile.

    Science.gov (United States)

    Bravo-Linares, Claudio; Schuller, Paulina; Castillo, Alejandra; Ovando-Fuentealba, Luis; Muñoz-Arcos, Enrique; Alarcón, Oscar; de Los Santos-Villalobos, Sergio; Cardoso, Renan; Muniz, Marcelo; Meigikos Dos Anjos, Roberto; Bustamante-Ortega, Ramón; Dercon, Gerd

    2018-03-15

    Land degradation is a problem affecting the sustainability of commercial forest plantations. The identification of critical areas prone to erosion can assist this activity to better target soil conservation efforts. Here we present the first use of the carbon-13 signatures of fatty acids (C14 to C24) in soil samples for spatial and temporal tracing of sediment transport in river bodies of upland commercial forest catchments in Chile. This compound-specific stable isotope (CSSI) technique was tested as a fingerprinting approach to determine the degree of soil erosion in pre-harvested forest catchments with surface areas ranging from 12 to 40ha. For soil apportionment a mixing model based on a Bayesian inference framework was used (CSSIAR v.2.0). Approximately four potential sediment sources were used for the calculations of all of the selected catchments. Unpaved forestry roads were shown to be the main source of sediment deposited at the outlet of the catchments (30-75%). Furthermore, sampling along the stream channel demonstrated that sediments were mainly comprised of sediment coming from the unpaved roads in the upper part of the catchments (74-98%). From this it was possible to identify the location and type of primary land use contributing to the sediment delivered at the outlet of the catchments. The derived information will allow management to focus efforts to control or mitigate soil erosion by improving the runoff features of the forest roads. The use of this CSSI technique has a high potential to help forestry managers and decision makers to evaluate and mitigate sources of soil erosion in upland forest catchments. It is important to highlight that this technique can also be a good complement to other soil erosion assessment and geological fingerprinting techniques, especially when attempting to quantify (sediment loads) and differentiate which type of land use most contributes to sediment accumulation. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Recovery of Pyruvic Acid using Tri-n-butylamine Dissolved in Non-Toxic Diluent (Rice Bran Oil)

    Science.gov (United States)

    Pal, Dharm; Keshav, Amit

    2016-04-01

    An attempt has been made to investigate the effectiveness of the vegetable oil based biocompatible solvent for the separation of pyruvic acid from fermentation broth, by using rice bran oil as natural, non-toxic diluent. Reactive extraction of pyruvic acid (0.1-0.5 k mol/m3) from aqueous solutions has been studied using tri-n-butylamine (TBA; 10-70 %) as an extractant dissolved in non toxic rice bran oil at T = 30 ± 1 °C. Results were presented in terms of distribution coefficient (Kd), extraction efficiency (E %), loading ratio (Z), and complexation constant (\\varphi_{α β }). Extraction equilibrium was interpreted using mass action modeling approach. Based on the extent of loading (Z < 0.5) only (1:1), pyruvic acid: TBA complex was proposed. Equilibrium complexation constant was evaluated to 1.22 m3/k mol. Results obtained are useful in understanding the extraction mechanism.

  4. High dietary quality of non-toxic cyanobacteria for a benthic grazer and its implications for the control of cyanobacterial biofilms.

    Science.gov (United States)

    Groendahl, Sophie; Fink, Patrick

    2017-05-18

    Mass occurrences of cyanobacteria frequently cause detrimental effects to the functioning of aquatic ecosystems. Consequently, attempts haven been made to control cyanobacterial blooms through naturally co-occurring herbivores. Control of cyanobacteria through herbivores often appears to be constrained by their low dietary quality, rather than by the possession of toxins, as also non-toxic cyanobacteria are hardly consumed by many herbivores. It was thus hypothesized that the consumption of non-toxic cyanobacteria may be improved when complemented with other high quality prey. We conducted a laboratory experiment in which we fed the herbivorous freshwater gastropod Lymnaea stagnalis single non-toxic cyanobacterial and unialgal diets or a mixed diet to test if diet-mixing may enable these herbivores to control non-toxic cyanobacterial mass abundances. The treatments where L. stagnalis were fed non-toxic cyanobacteria and a mixed diet provided a significantly higher shell and soft-body growth rate than the average of all single algal, but not the non-toxic cyanobacterial diets. However, the increase in growth provided by the non-toxic cyanobacteria diets could not be related to typical determinants of dietary quality such as toxicity, nutrient stoichiometry or essential fatty acid content. These results strongly contradict previous research which describes non-toxic cyanobacteria as a low quality food resource for freshwater herbivores in general. Our findings thus have strong implications to gastropod-cyanobacteria relationships and suggest that freshwater gastropods may be able to control mass occurrences of benthic non-toxic cyanobacteria, frequently observed in eutrophied water bodies worldwide.

  5. Stimulation of wild-type, F508del- and G551D-CFTR chloride channels by non toxic modified pyrrolo[2,3-b]pyrazine derivatives

    Directory of Open Access Journals (Sweden)

    Luc eDannhoffer

    2011-08-01

    Full Text Available Cystic Fibrosis is a major inherited disorder involving abnormalities of fluid and electrolyte transport in a number of different organs due to abnormal function of Cystic Fibrosis Transmembrane conductance Regulator (CFTR protein. We recently identified a family of CFTR activators, which contains the hit: RP107 [7-n-butyl-6-(4-hydroxyphenyl[5H]-pyrrolo[2,3-b]pyrazine]. Here, we further evaluated the effect of the chemical modifications of the RP107-OH radical on CFTR activation. The replacement of the OH radical by a fluorine atom at position 2 (RP193 or 4 (RP185 significantly decreased the toxicity of the compounds without altering the ability to activate CFTR, especially for RP193. The non-toxic compound RP193 has no effect on cAMP production but stimulates the channel activity of wild-type CFTR in stably transfected CHO cells, in human bronchial epithelial NuLi-1 cells and in primary culture of human bronchial epithelial cells. Whole cell and single patch clamp recordings showed that RP193 induced a linear, time and voltage-independent current, which was fully inhibited by two different and selective CFTR inhibitors (CFTRinh-172 and GPinh-5a. Moreover, RP193 stimulates CFTR in temperature-rescued CuFi-1 (F508del/F508del human bronchial epithelial cells and in CHO cells stably expressing G551D-CFTR. This study shows that it is feasible to reduce cytotoxicity of chemical compounds without affecting their potency to activate CFTR and to rescue the class 2 F508del-CFTR and class 3 G551D-CFTR CF mutant activities.

  6. Non toxic biodegradable cationic gemini surfactants as novel corrosion inhibitor for mild steel in hydrochloric acid medium and synergistic effect of sodium salicylate: Experimental and theoretical approach

    Energy Technology Data Exchange (ETDEWEB)

    Mobin, Mohammad, E-mail: drmmobin@hotmail.com; Aslam, Ruby; Aslam, Jeenat

    2017-04-15

    Two biodegradable, non toxic cationic gemini surfactants having ester linkage in the spacer namely, C{sub m}H{sub 2m+1}(CH{sub 3}){sub 2}N{sup +}(CH{sub 2}COOCH{sub 2}){sub 2}N{sup +}(CH{sub 3}){sub 2}C{sub m}H{sub 2m+1}.2Cl{sup -} (m-E2-m, m = 12, 14), were synthesized and characterized using elemental analysis, FT-IR and {sup 1}H-NMR. The corrosion inhibition performance of synthesized compounds separately and in combination with sodium salicylate (SS), along with the nature and stability of inhibitive film, for mild steel (MS) in 1 M HCl solution at 30–60 °C was evaluated using weight loss, potentiodynamic polarization, EIS, UV–visible spectroscopy, FTIR, SEM/EDAX, TGA and quantum chemical calculations. Results of the studies confirm m-E2-m as effective corrosion inhibitor for MS in HCl; the inhibition effect being synergistically strengthened in presence of SS. The synthesized compounds act as mixed type inhibitor and adsorb on MS surface in accordance with Langmuir adsorption isotherm. Experimentally measured inhibition efficiencies are correlated with the molecular parameters obtained using PM6 semi-empirical method. Empirical results are in good agreement with the theoretical predictions. - Graphical abstract: (a) Optimized geometry of studied inhibitors by PM6 method with (b) HOMO and (c) LUMO orbital occupation. - Highlights: • Environment friendly gemini surfactants were studied as corrosion inhibitor for MS. • Studied compounds act as good inhibitor for MS corrosion in 1 M HCl at 30–60 °C. • η of inhibitors is synergistically increased in presence of sodium salicylate. • The synthesized cationic gemini surfactants act as mixed-type inhibitor. • Experimentally obtained results are in good agreement with theoretical results.

  7. 3-Aminothiophene-2-Acylhydrazones: Non-Toxic, Analgesic and Anti-Inflammatory Lead-Candidates

    Directory of Open Access Journals (Sweden)

    Yolanda Karla Cupertino da Silva

    2014-06-01

    Full Text Available Different chemotypes are described as anti-inflammatory. Among them the N-acylhydrazones (NAH are highlighted by their privileged structure nature, being present in several anti-inflammatory drug-candidates. In this paper a series of functionalized 3-aminothiophene-2-acylhydrazone derivatives 5a–i were designed, synthesized and bioassayed. These new derivatives showed great anti-inflammatory and analgesic potency and efficacy. Compounds 5a and 5d stand out in this respect, and were also active in CFA-induced arthritis in rats. After daily treatment for seven days with 5a and 5d (50 µmol/Kg, by oral administration, these compounds were not renal or hepatotoxic nor immunosuppressive. Compounds 5a and 5d also displayed good drug-scores and low risk toxicity calculated in silico using the program OSIRIS Property Explorer.

  8. Effect of zinc compounds on Fusarium verticillioides growth, hyphae alterations, conidia, and fumonisin production.

    Science.gov (United States)

    Savi, Geovana D; Vitorino, Vinícius; Bortoluzzi, Adailton J; Scussel, Vildes M

    2013-10-01

    Several strategies are used to eliminate toxigenic fungi that produce fumonisins in grains. Fusarium verticillioides can be controlled by the application of synthetic fungicides in the field or during storage. However, there may also be residuals, which may remain in the foods. Inorganic compounds such as zinc are cheap, stable and could present strong antifungal activity. Some Zn compounds can be utilized as dietary supplements and are authorized for the fortification of foods. Knowing the advantages and that low concentrations of Zn can have antimicrobial activity, our objective was to evaluate the effects of Zn compounds on the growth of F. verticillioides and the production of fumonisin and conidia. In addition, we aimed to verify that Zn compounds cause morphological alterations of the hyphae, mortality and production of reactive oxygen species. Zn compounds efficiently reduced fungal growth and fumonisin production. Treatment using zinc perchlorate gave the best results. All treatments inhibited conidia production and caused morphological alterations of the hyphae. It was possible to observe cell death and production of reactive oxygen species. Zn compounds have advantages compared to other antifungal compounds. In particular, they are non-toxic for the organism in appropriate amounts. They could be studied further as potential fungicides in agriculture. © 2013 Society of Chemical Industry.

  9. Complementing approaches to demonstrate chlorinated solvent biodegradation in a complex pollution plume: Mass balance, PCR and compound-specific stable isotope analysis

    Science.gov (United States)

    Courbet, Christelle; Rivière, Agnès; Jeannottat, Simon; Rinaldi, Sandro; Hunkeler, Daniel; Bendjoudi, Hocine; de Marsily, Ghislain

    2011-11-01

    This work describes the use of different complementing methods (mass balance, polymerase chain reaction assays and compound-specific stable isotope analysis) to demonstrate the existence and effectiveness of biodegradation of chlorinated solvents in an alluvial aquifer. The solvent-contaminated site is an old chemical factory located in an alluvial plain in France. As most of the chlorinated contaminants currently found in the groundwater at this site were produced by local industries at various times in the past, it is not enough to analyze chlorinated solvent concentrations along a flow path to convincingly demonstrate biodegradation. Moreover, only a few data were initially available to characterize the geochemical conditions at this site, which were apparently complex at the source zone due to (i) the presence of a steady oxygen supply to the groundwater by irrigation canal losses and river infiltration and (ii) an alkaline pH higher than 10 due to former underground lime disposal. A demonstration of the existence of biodegradation processes was however required by the regulatory authority within a timeframe that did not allow a full geochemical characterization of such a complex site. Thus a combination of different fast methods was used to obtain a proof of the biodegradation occurrence. First, a mass balance analysis was performed which revealed the existence of a strong natural attenuation process (biodegradation, volatilization or dilution), despite the huge uncertainty on these calculations. Second, a good agreement was found between carbon isotopic measurements and PCR assays (based on 16S RNA gene sequences and functional genes), which clearly indicated reductive dechlorination of different hydrocarbons (Tetrachloroethene—PCE-, Trichloroethene—TCE-, 1,2- cisDichloroethene— cis-1,2-DCE-, 1,2- transDichloroethene— trans-1,2-DCE-, 1,1-Dichloroethene—1,1-DCE-, and Vinyl Chloride—VC) to ethene. According to these carbon isotope measurements

  10. Potential of Annona muricata L. seed oil: phytochemical and nutritional characterization associated with non-toxicity

    Directory of Open Access Journals (Sweden)

    L. C. Pinto

    2018-03-01

    Full Text Available The aim of this study was to evaluate the nutritional quality, phenolic compounds, fatty acid and antioxidant activity in vitro as well as a toxicological screening of A. muricata seed oil in vivo. The chemical composition and quantification of phenolic compounds were determined by the Adolfo Lutz Institute normative. The antioxidant activity was evaluated by DPPH, FRAP and ABTS methods. The oil was extracted by chloroform/ methanol and precipitated crude (AmPtO and supernatant oils (AmSO were obtained. The fatty acid profile was evaluated by gas chromatography and total compounds by HPLC-DAD. BALB/C mice received AmPtO and AmSO (0.5 and 1.0mL·Kg-1 for 14 days. Toxicity parameters were assessed. The major fatty acids in the oil were oleic (39.2% and linoleic (33%. HPLC-DAD suggested the presence of acetogenins (annonacin: 595 [M-H]-, with a greater presence in AmPtO. The AmPtO group showed toxicity, which may be related to the acetogenin content in AmPtO. The AmSO group showed no toxicity and this oil has potential for food or medicinal use.

  11. Solid-state, ambient-operation thermally activated delayed fluorescence from flexible, non-toxic gold-nanocluster thin films: towards the development of biocompatible light-emitting devices

    Science.gov (United States)

    Talite, M. J. A.; Lin, H. T.; Jiang, Z. C.; Lin, T. N.; Huang, H. Y.; Heredia, E.; Flores, A.; Chao, Y. C.; Shen, J. L.; Lin, C. A. J.; Yuan, C. T.

    2016-08-01

    Luminescent gold nanoclusters (AuNCs) with good biocompatibility have gained much attention in bio-photonics. In addition, they also exhibit a unique photo-physical property, namely thermally activated delayed fluorescence (TADF), by which both singlet and triplet excitons can be harvested. The combination of their non-toxic material property and unique TADF behavior makes AuNCs biocompatible nano-emitters for bio-related light-emitting devices. Unfortunately, the TADF emission is quenched when colloidal AuNCs are transferred to solid states under ambient environment. Here, a facile, low-cost and effective method was used to generate efficient and stable TADF emissions from solid AuNCs under ambient environment using polyvinyl alcohol as a solid matrix. To unravel the underlying mechanism, temperature-dependent static and transient photoluminescence measurements were performed and we found that two factors are crucial for solid TADF emission: small energy splitting between singlet and triplet states and the stabilization of the triplet states. Solid TADF films were also deposited on the flexible plastic substrate with patterned structures, thus mitigating the waveguide-mode losses. In addition, we also demonstrated that warm white light can be generated based on a co-doped single emissive layer, consisting of non-toxic, solution-processed TADF AuNCs and fluorescent carbon dots under UV excitation.

  12. Non-toxic poly(ethylene terephthalate)/clay nanocomposites with enhanced barrier properties

    KAUST Repository

    Hayrapetyan, Suren

    2012-01-01

    Motivated by the technological need for poly(ethylene terephthalate) materials with improved barrier properties together with the requirement for sustainability this study focuses on an eco-friendly sulfonated polyester as clay compatibilizer to facilitate polymer mixing during melt compounding. We demonstrate that the nanocomposites based on sulfonated polyester are a reliable alternative to their imidazolium counterparts, exhibiting enhanced properties (water vapor and UV transmission), without sacrificing the excellent transparency, clarity and mechanical strength of the matrix. © 2011 Elsevier Ltd. All rights reserved.

  13. Insights into the Key Aroma Compounds in Mango (Mangifera indica L. 'Haden') Fruits by Stable Isotope Dilution Quantitation and Aroma Simulation Experiments.

    Science.gov (United States)

    Munafo, John P; Didzbalis, John; Schnell, Raymond J; Steinhaus, Martin

    2016-06-01

    Thirty-four aroma-active compounds, previously identified with high flavor dilution factors by application of an aroma extract dilution analysis, were quantified in tree-ripened fruits of mango (Mangifera indica L. 'Haden'). From the results, the odor activity value (OAV) was calculated for each compound as the ratio of its concentration in the mangoes to its odor threshold in water. OAVs > 1 were obtained for 24 compounds, among which ethyl 2-methylbutanoate (fruity; OAV 2100), (3E,5Z)-undeca-1,3,5-triene (pineapple-like; OAV 1900), ethyl 3-methylbutanoate (fruity; OAV 1600), and ethyl butanoate (fruity; OAV 980) were the most potent, followed by (2E,6Z)-nona-2,6-dienal (cucumber-like), ethyl 2-methylpropanoate (fruity), (E)-β-damascenone (cooked apple-like), ethyl hexanoate (fruity), 4-hydroxy-2,5-dimethyl-3(2H)-furanone (caramel-like), 3-methylbut-2-ene-1-thiol (sulfurous), γ-decalactone (peach-like), β-myrcene (terpeny), (3Z)-hex-3-enal (green), 4-methyl-4-sulfanylpentan-2-one (tropical fruit-like), and ethyl octanoate (fruity). Aroma simulation and omission experiments revealed that these 15 compounds, when combined in a model mixture in their natural concentrations, were able to mimic the aroma of the fruits.

  14. Evaluation of some non-toxic thiadiazole derivatives as bronze corrosion inhibitors in aqueous solution

    International Nuclear Information System (INIS)

    Varvara, Simona; Muresan, Liana Maria; Rahmouni, Kamal; Takenouti, Hisasi

    2008-01-01

    The inhibiting effect of four innoxious thiadiazole derivatives (2-mercapto-5-amino-1,3,4-thiadiazole (MAT), 2-mercapto-5-acetylamino-1,3,4-thiadiazole (MAcAT), 2-mercapto-5-methyl-1,3,4-thiadiazole (MMeT) and 2-mercapto-5-phenylamino-1,3,4-thiadiazole (MPhAT)) on bronze corrosion in an aerated solution of 0.2 g L -1 Na 2 SO 4 + 0.2 g L -1 NaHCO 3 at pH 5 was studied by potentiodynamic voltammetry and electrochemical impedance spectroscopy. The corrosion parameters determined from the polarisation curves indicate that the addition of the investigated thiadiazole derivatives decreases both cathodic and anodic current densities, due to an inhibition of the corrosion process, through the adsorption of thiadiazoles on the bronze surface. The inhibiting effect of the investigated organic compounds appears to be more pronounced on the anodic process than on the cathodic one and, except for the case MPhAT, it is enhanced by the increases of the inhibitors' concentration. The adsorption of the thiadiazole derivatives on bronze was confirmed by the presence of the nitrogen atoms in the EDX spectra of the bronze exposed to inhibitor-containing solutions. The magnitude of polarisation resistance values and, consequently, the inhibition efficiencies are influenced by the molecular structure of thiadiazole derivatives. The strongest inhibition was noticed in the presence of compounds with phenyl amino- or amino-functionalities in their molecules. The maximum protection efficiencies were obtained by addition of: 5 mM MAT (95.9%), 1 mM MAcAT (95.7%), 5 mM MMeT (92.6%) and 0.1 mM MPhAT (97%). EIS measurements also revealed that the inhibitor effectiveness of the optimal concentrations of thiadiazole is time-dependent

  15. Evaluation of some non-toxic thiadiazole derivatives as bronze corrosion inhibitors in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Varvara, Simona [Department of Topography, ' 1 Decembrie 1918' University, 11-13 Nicolae Iorga Street, 510009 Alba Iulia (Romania); Muresan, Liana Maria [Department of Physical Chemistry, ' Babes-Bolyai' University, 11 Arany-Janos Street, 400028 Cluj-Napoca (Romania)], E-mail: limur@chem.ubbcluj.ro; Rahmouni, Kamal; Takenouti, Hisasi [UPMC LISE - UPR 15 of the CNRS, ' Pierre and Marie Curie' University, Paris (France)

    2008-09-15

    The inhibiting effect of four innoxious thiadiazole derivatives (2-mercapto-5-amino-1,3,4-thiadiazole (MAT), 2-mercapto-5-acetylamino-1,3,4-thiadiazole (MAcAT), 2-mercapto-5-methyl-1,3,4-thiadiazole (MMeT) and 2-mercapto-5-phenylamino-1,3,4-thiadiazole (MPhAT)) on bronze corrosion in an aerated solution of 0.2 g L{sup -1} Na{sub 2}SO{sub 4} + 0.2 g L{sup -1} NaHCO{sub 3} at pH 5 was studied by potentiodynamic voltammetry and electrochemical impedance spectroscopy. The corrosion parameters determined from the polarisation curves indicate that the addition of the investigated thiadiazole derivatives decreases both cathodic and anodic current densities, due to an inhibition of the corrosion process, through the adsorption of thiadiazoles on the bronze surface. The inhibiting effect of the investigated organic compounds appears to be more pronounced on the anodic process than on the cathodic one and, except for the case MPhAT, it is enhanced by the increases of the inhibitors' concentration. The adsorption of the thiadiazole derivatives on bronze was confirmed by the presence of the nitrogen atoms in the EDX spectra of the bronze exposed to inhibitor-containing solutions. The magnitude of polarisation resistance values and, consequently, the inhibition efficiencies are influenced by the molecular structure of thiadiazole derivatives. The strongest inhibition was noticed in the presence of compounds with phenyl amino- or amino-functionalities in their molecules. The maximum protection efficiencies were obtained by addition of: 5 mM MAT (95.9%), 1 mM MAcAT (95.7%), 5 mM MMeT (92.6%) and 0.1 mM MPhAT (97%). EIS measurements also revealed that the inhibitor effectiveness of the optimal concentrations of thiadiazole is time-dependent.

  16. Emergence of a few distinct structures from a single formal structure type during high-throughput screening for stable compounds: The case of RbCuS and RbCuSe

    Science.gov (United States)

    Trimarchi, Giancarlo; Zhang, Xiuwen; DeVries Vermeer, Michael J.; Cantwell, Jacqueline; Poeppelmeier, Kenneth R.; Zunger, Alex

    2015-10-01

    Theoretical sorting of stable and synthesizable "missing compounds" from those that are unstable is a crucial step in the discovery of previously unknown functional materials. This active research area often involves high-throughput (HT) examination of the total energy of a given compound in a list of candidate formal structure types (FSTs), searching for those with the lowest energy within that list. While it is well appreciated that local relaxation methods based on a fixed list of structure types can lead to inaccurate geometries, this approach is widely used in HT studies because it produces answers faster than global optimization methods (that vary lattice vectors and atomic positions without local restrictions). We find, however, a different failure mode of the HT protocol: specific crystallographic classes of formal structure types each correspond to a series of chemically distinct "daughter structure types" (DSTs) that have the same space group but possess totally different local bonding configurations, including coordination types. Failure to include such DSTs in the fixed list of examined candidate structures used in contemporary high-throughput approaches can lead to qualitative misidentification of the stable bonding pattern, not just quantitative inaccuracies. In this work, we (i) clarify the understanding of the general DST-FST relationship, thus improving current discovery HT approaches, (ii) illustrate this failure mode for RbCuS and RbCuSe (the latter being a yet unreported compound and is predicted here) by developing a synthesis method and accelerated crystal-structure determination, and (iii) apply the genetic-algorithm-based global space-group optimization (GSGO) approach which is not vulnerable to the failure mode of HT searches of fixed lists, demonstrating a correct identification of the stable DST. The broad impact of items (i)-(iii) lies in the demonstrated predictive ability of a more comprehensive search strategy than what is currently

  17. Radionuclides, stable isotopes, inorganic constituents, and organic compounds in water from selected wells and springs from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman Area, Idaho, 1995

    International Nuclear Information System (INIS)

    Bartholomay, R.C.; Williams, L.M.; Campbell, L.J.

    1996-09-01

    The US Geological Survey and the Idaho Department of Water Resources, in cooperation with the US Department of Energy, sampled 17 sites as part of a long-term project to monitor water quality of the Snake River Plain aquifer from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman area. Water samples were collected and analyzed for selected radionuclides, stable isotopes, inorganic constituents, and organic compounds. The samples were collected from 11 irrigation wells, 2 domestic wells, 2 stock wells, 1 spring, and 1 public-supply well. Two quality assurance samples also were collected and analyzed. None of the radionuclide, inorganic constituents, or organic compound concentrations exceeded the established maximum contaminant levels for drinking water. Many of the radionuclide and inorganic constituent concentrations were greater than their respective reporting levels. All samples analyzed for dissolved organic carbon had concentrations that were greater than the minimum reporting level

  18. Behavior of radon, chemical compounds and stable elements in underground water; Comportamiento de radon, compuestos quimicos y elementos estables en agua subterranea

    Energy Technology Data Exchange (ETDEWEB)

    Lopez R, N.; Segovia, N.; Lopez, M.B.E.; Pena, P. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Armienta, M.A.; Godinez, L. [IGFUNAM, Ciudad Universitaria, 04510 Mexico D.F. (Mexico); Seidel, J.L. [ISTEEM, M.S.E. Montpellier (France)

    2001-07-01

    The radon behavior, chemical compounds, major and trace elements in water samples of four springs and three wells of urban and agricultural zones around the Jocotitlan volcano and El Oro region was determined, both of them located in the medium part of the Mexican neo-volcanic axis. The {sup 222} Rn was measured by the liquid scintillation method, the analysis of major components was realized with conventional chemical techniques, while the trace elements were quantified using an Icp-Ms. The average values of the radon concentrations obtained during one year were constant relatively, in an interval from 0.97 to 4.99 Bq/lt indicating a fast transport from the reload area toward the sampling points. the compounds, major and trace elements showed differences which indicate distinct origins of water from the site studies. (Author)

  19. High Relative Abundance of Biofuel Sourced Ethanol in Precipitation in the US and Brazil Determined Using Compound Specific Stable Carbon Isotopes

    Science.gov (United States)

    Shimizu, M. S.; Felix, J. D. D.; Casas, M.; Avery, G. B., Jr.; Kieber, R. J.; Mead, R. N.; Willey, J. D.; Lane, C.

    2017-12-01

    Ethanol biofuel production and consumption have increased exponentially over the last two decades to help reduce greenhouse gas emissions. Currently, 85% of global ethanol production and consumption occurs in the US and Brazil. Increasing biofuel ethanol usage in these two countries enhances emissions of uncombusted ethanol to the atmosphere contributing to poor air quality. Although measurements of ethanol in the air and the precipitation reveal elevated ethanol concentrations in densely populated cities, other sources such as natural vegetation can contribute to emission to the atmosphere. Previous modeling studies indicated up to 12% of atmospheric ethanol is from anthropogenic emissions. Only one gas phase study in southern Florida attempted to constrain the two sources through direct isotopic measurements. The current study used a stable carbon isotope method to constrain sources of ethanol in rainwater from the US and Brazil. A method was developed using solid phase microextraction (SPME) with subsequent analysis by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). Stable carbon isotope signatures (δ13C) of vehicle ethanol emission sources for both the US (-9.8‰) and Brazil (-12.7‰) represented C4 plants as feedstock (corn and sugarcane) for biofuel production. An isotope mixing model using biofuel from vehicles (C4 plants) and biogenic (C3 plants) end-members was implemented to estimate ethanol source apportionment in the rain. We found that stable carbon isotope ratio of ethanol in the rain ranged between -22.6‰ and -12.7‰. Our results suggest that the contribution of biofuel to atmospheric ethanol can be higher than previously estimated. As biofuel usage increasing globally, it is essential to determine the relative abundance of anthropogenic ethanol in other areas of the world.

  20. Non-toxic engineered carbon nanodiamond concentrations induce oxidative/nitrosative stress, imbalance of energy metabolism, and mitochondrial dysfunction in microglial and alveolar basal epithelial cells.

    Science.gov (United States)

    Fresta, Claudia G; Chakraborty, Aishik; Wijesinghe, Manjula B; Amorini, Angela M; Lazzarino, Giacomo; Lazzarino, Giuseppe; Tavazzi, Barbara; Lunte, Susan M; Caraci, Filippo; Dhar, Prajnaparamita; Caruso, Giuseppe

    2018-02-14

    Engineered nanoparticles are finding a wide spectrum of biomedical applications, including drug delivery and capacity to trigger cytotoxic phenomena, potentially useful against tumor cells. The full understanding of their biosafety and interactions with cell processes is mandatory. Using microglial (BV-2) and alveolar basal epithelial (A549) cells, in this study we determined the effects of engineered carbon nanodiamonds (ECNs) on cell viability, nitric oxide (NO) and reactive oxygen species (ROS) production, as well as on energy metabolism. Particularly, we initially measured decrease in cell viability as a function of increasing ECNs doses, finding similar cytotoxic ECN effects in the two cell lines. Subsequently, using apparently non-cytotoxic ECN concentrations (2 µg/mL causing decrease in cell number < 5%) we determined NO and ROS production, and measured the concentrations of compounds related to energy metabolism, mitochondrial functions, oxido-reductive reactions, and antioxidant defences. We found that in both cell lines non-cytotoxic ECN concentrations increased NO and ROS production with sustained oxidative/nitrosative stress, and caused energy metabolism imbalance (decrease in high energy phosphates and nicotinic coenzymes) and mitochondrial malfunctioning (decrease in ATP/ADP ratio).These results underline the importance to deeply investigate the molecular and biochemical changes occurring upon the interaction of ECNs (and nanoparticles in general) with living cells, even at apparently non-toxic concentration. Since the use of ECNs in biomedical field is attracting increasing attention the complete evaluation of their biosafety, toxicity and/or possible side effects both in vitro and in vivo is mandatory before these highly promising tools might find the correct application.

  1. Chitosan-based microcapsules containing grapefruit seed extract grafted onto cellulose fibers by a non-toxic procedure.

    Science.gov (United States)

    Alonso, Diana; Gimeno, Miquel; Sepúlveda-Sánchez, José D; Shirai, Keiko

    2010-04-19

    A novel non-toxic procedure is described for the grafting of chitosan-based microcapsules containing grapefruit seed oil extract onto cellulose. The cellulose was previously UV-irradiated and then functionalized from an aqueous emulsion of the chitosan with the essential oil. The novel materials are readily attained with durable fragrance and enhanced antimicrobial properties. The incorporation of chitosan as determined from the elemental analyses data was 16.08+/-0.29 mg/g of sample. Scanning electron microscopy (SEM) and gas chromatography-mass spectroscopy (GC-MS) provided further evidence for the successful attachment of chitosan microcapsules containing the essential oil to the treated cellulose fibers. The materials thus produced displayed 100% inhibition of Escherichia coli and Staphylococcus epidermidis up to 48 h of incubation. Inhibition of bacteria by the essential oil was also evaluated at several concentrations. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  2. Plant regeneration of non-toxic Jatropha curcas—impacts of plant growth regulators, source and type of explants

    KAUST Repository

    Kumar, Nitish

    2011-01-28

    Jatropha curcas is an oil bearing species with multiple uses and considerable economic potential as a biofuel plant, however, oil and deoiled cake are toxic. A non-toxic variety of J. curcas is reported from Mexico. The present investigation explores the effects of different plant growth regulators (PGRs) viz. 6-benzyl aminopurine (BAP) or thidiazuron (TDZ) individually and in combination with indole-3-butyric acid (IBA), on regeneration from in vitro and field-grown mature leaf explants, in vitro and glasshouse-grown seedlings cotyledonary leaf explants of non-toxic J. curcas. In all the tested parameters maximum regeneration efficiency (81.07%) and the number of shoot buds per explants (20.17) was observed on 9.08 μM TDZ containing Murashige and Skoog’s (MS) medium from in vitro cotyledonary leaf explants. The regenerated shoot buds were transferred to MS medium containing 10 μM kinetin (Kn), 4.5 μM BAP and 5.5 μM α-naphthaleneacetic acid (NAA) for shoot proliferation. The proliferated shoots could be elongated on MS medium supplemented with 2.25 μM BAP and 8.5 μM IAA. Rooting was achieved when the basal cut end of elongated shoots were dipped in half strength MS liquid medium containing different concentrations and combinations of IBA, IAA and NAA for four days followed by transfer to growth regulators free half strength MS medium supplemented 0.25 mg/l activated charcoal. The rooted plants could be established in soil with more than 90% survival rate.

  3. Plant regeneration of non-toxic Jatropha curcas—impacts of plant growth regulators, source and type of explants

    KAUST Repository

    Kumar, Nitish; Vijay Anand, K. G.; Reddy, Muppala P.

    2011-01-01

    Jatropha curcas is an oil bearing species with multiple uses and considerable economic potential as a biofuel plant, however, oil and deoiled cake are toxic. A non-toxic variety of J. curcas is reported from Mexico. The present investigation explores the effects of different plant growth regulators (PGRs) viz. 6-benzyl aminopurine (BAP) or thidiazuron (TDZ) individually and in combination with indole-3-butyric acid (IBA), on regeneration from in vitro and field-grown mature leaf explants, in vitro and glasshouse-grown seedlings cotyledonary leaf explants of non-toxic J. curcas. In all the tested parameters maximum regeneration efficiency (81.07%) and the number of shoot buds per explants (20.17) was observed on 9.08 μM TDZ containing Murashige and Skoog’s (MS) medium from in vitro cotyledonary leaf explants. The regenerated shoot buds were transferred to MS medium containing 10 μM kinetin (Kn), 4.5 μM BAP and 5.5 μM α-naphthaleneacetic acid (NAA) for shoot proliferation. The proliferated shoots could be elongated on MS medium supplemented with 2.25 μM BAP and 8.5 μM IAA. Rooting was achieved when the basal cut end of elongated shoots were dipped in half strength MS liquid medium containing different concentrations and combinations of IBA, IAA and NAA for four days followed by transfer to growth regulators free half strength MS medium supplemented 0.25 mg/l activated charcoal. The rooted plants could be established in soil with more than 90% survival rate.

  4. Stable isotope utilization for research on human nutrition

    International Nuclear Information System (INIS)

    Desjeux, J.F.

    1994-01-01

    In the framework of nutritional molecule metabolism research, this paper presents the various stable isotopes used as labels for biological molecules, the reasons for their application in human nutritional study (mainly because of their non toxicity) and the various analysis methods (isotope ratio mass spectrometry, coupled gaseous chromatography and mass spectrometry, nuclear magnetic resonance). Several application examples in nutrition research are then discussed: metabolic conversion measurement for a molecule into its different metabolites, energetic losses. 23 refs

  5. Stabilizing the baseline current of a microbial fuel cell-based biosensor through overpotential control under non-toxic conditions.

    Science.gov (United States)

    Stein, Nienke E; Hamelers, Hubertus V M; Buisman, Cees N J

    2010-04-01

    A MFC-based biosensor can act as online toxicity sensor. Electrical current is a direct linear measure for metabolic activity of electrochemically active microorganisms. Microorganisms gain energy from anodic overpotential and current strongly depends on anodic overpotential. Therefore control of anodic overpotential is necessary to detect toxic events and prevent false positive alarms. Anodic overpotential and thus current is influenced by anode potential, pH, substrate and bicarbonate concentrations. In terms of overpotential all factor showed a comparable effect, anode potential 1.2% change in current density per mV, pH 0.43%/mV, bicarbonate 0.75%/mV and acetate 0.8%/mV. At acetate saturation the maximum acetate conversion rate is reached and with that a constant bicarbonate concentration. Control of acetate and bicarbonate concentration can be less strict than control of anode potential and pH. Current density changes due to changing anode potential and pH are in the same order of magnitude as changes due to toxicity. Strict control of pH and anode potential in a small range is required. The importance of anodic overpotential control for detection of toxic compounds is shown. To reach a stable baseline current under nontoxic conditions a MFC-based biosensor should be operated at controlled anode potential, controlled pH and saturated substrate concentrations. 2009 Elsevier B.V. All rights reserved.

  6. Comparison of leaf gas exchange and stable isotope signature of water-soluble compounds along canopy gradients of co-occurring Douglas-fir and European beech.

    Science.gov (United States)

    Bögelein, Rebekka; Hassdenteufel, Martin; Thomas, Frank M; Werner, Willy

    2012-07-01

    Combined δ(13) C and δ(18) O analyses of water-soluble leaf and twig phloem material were used to determine intrinsic water-use efficiency (iWUE) and variability of stomatal conductance at different crown positions in adult European beech (Fagus sylvatica) and Douglas-fir (Pseudotsuga menziesii) trees. Simultaneous gas exchange measurements allowed evaluation of the differences in calculating iWUE from leaf or phloem water-soluble compounds, and comparison with a semi-quantitative dual isotope model to infer variability of net photosynthesis (A(n) ) between the investigated crown positions. Estimates of iWUE from δ(13) C of leaf water-soluble organic matter (WSOM) outperformed the estimates from phloem compounds. In the beech crown, δ(13) C of leaf WSOM coincided clearly with gas exchange measurements. The relationship was not as reliable in the Douglas-fir. The differences in δ(18) O between leaf and phloem material were found to correlate with stomatal conductance. The semi-quantitative model approach was applicable for comparisons of daily average A(n) between different crown positions and trees. Intracanopy gradients were more pronounced in the beech than in the Douglas-fir, which reached higher values of iWUE at the respective positions, particularly under dry air conditions. © 2012 Blackwell Publishing Ltd.

  7. Tracing fresh assimilates through Larix decidua exposed to elevated CO₂ and soil warming at the alpine treeline using compound-specific stable isotope analysis.

    Science.gov (United States)

    Streit, Kathrin; Rinne, Katja T; Hagedorn, Frank; Dawes, Melissa A; Saurer, Matthias; Hoch, Günter; Werner, Roland A; Buchmann, Nina; Siegwolf, Rolf T W

    2013-02-01

    How will carbon source-sink relations of 35-yr-old larch trees (Larix decidua) at the alpine treeline respond to changes in atmospheric CO(2) and climate? We evaluated the effects of previously elevated CO(2) concentrations (9 yr, 580 ppm, ended the previous season) and ongoing soil warming (4 yr, + 4°C). Larch branches were pulse labeled (50 at% (13)CO(2)) in July 2010 to trace fresh assimilates through tissues (buds, needles, bark and wood) and non-structural carbon compounds (NCC; starch, lipids, individual sugars) using compound-specific isotope analysis. Nine years of elevated CO(2) did not lead to increased NCC concentrations, nor did soil warming increase NCC transfer velocities. By contrast, we found slower transfer velocities and higher NCC concentrations than reported in the literature for lowland larch. As a result of low dilution with older carbon, sucrose and glucose showed the highest maximum (13)C labels, whereas labels were lower for starch, lipids and pinitol. Label residence times in needles were shorter for sucrose and starch (c. 2 d) than for glucose (c. 6 d). Although our treatments showed no persistent effect on larch carbon relations, low temperature at high altitudes clearly induced a limitation of sink activities (growth, respiration, root exudation), expressed in slower carbon transfer and higher NCC concentrations. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  8. Liquid structure as a guide for phase stability in the solid state: Discovery of a stable compound in the Au-Si alloy system

    International Nuclear Information System (INIS)

    Tasci, Emre S.; Sluiter, Marcel H.F.; Pasturel, Alain; Villars, Pierre

    2010-01-01

    A new crystalline ground state was discovered in the Au-Si system through first-principles electronic structure calculations. The new structure was found using the experimentally and theoretically determined local atomic structure in the liquid as a guide for the solid state. Local atomic structure in the liquid was matched with that for all known crystal structures as compiled in the Pauling File structural database. The best matching crystalline structures were then explicitly calculated using first-principles methods. Most candidate crystal structures were found to be close, but above the enthalpy of a composition weighted average of the face-centered cubic Au and diamond structure Si terminal phases, but one crystal structure was more stable than the terminal phases by about 10 meV atom -1 at T = 0 K. As first-principles simulations of local structure are feasible for most liquid alloys, the present methodology is applicable to other alloys lying near a eutectic composition.

  9. Synthesis and fundamental properties of stable Ph(3)SnSiH(3) and Ph(3)SnGeH(3) hydrides: model compounds for the design of Si-Ge-Sn photonic alloys.

    Science.gov (United States)

    Tice, Jesse B; Chizmeshya, Andrew V G; Groy, Thomas L; Kouvetakis, John

    2009-07-06

    The compounds Ph(3)SnSiH(3) and Ph(3)SnGeH(3) (Ph = C(6)H(5)) have been synthesized as colorless solids containing Sn-MH(3) (M = Si, Ge) moieties that are stable in air despite the presence of multiple and highly reactive Si-H and Ge-H bonds. These molecules are of interest since they represent potential model compounds for the design of new classes of IR semiconductors in the Si-Ge-Sn system. Their unexpected stability and high solubility also makes them a safe, convenient, and potentially useful delivery source of -SiH(3) and -GeH(3) ligands in molecular synthesis. The structure and composition of both compounds has been determined by chemical analysis and a range of spectroscopic methods including multinuclear NMR. Single crystal X-ray structures were determined and indicated that both compounds condense in a Z = 2 triclinic (P1) space group with lattice parameters (a = 9.7754(4) A, b = 9.8008(4) A, c = 10.4093(5) A, alpha = 73.35(10)(o), beta = 65.39(10)(o), gamma = 73.18(10)(o)) for Ph(3)SnSiH(3) and (a = 9.7927(2) A, b = 9.8005(2) A, c = 10.4224(2) A, alpha = 74.01(3)(o), beta = 65.48(3)(o), gamma = 73.43(3)(o)) for Ph(3)SnGeH(3). First principles density functional theory simulations are used to corroborate the molecular structures of Ph(3)SnSiH(3) and Ph(3)SnGeH(3), gain valuable insight into the relative stability of the two compounds, and provide correlations between the Si-Sn and Ge-Sn bonds in the molecules and those in tetrahedral Si-Ge-Sn solids.

  10. Stable isotopes

    International Nuclear Information System (INIS)

    Evans, D.K.

    1986-01-01

    Seventy-five percent of the world's stable isotope supply comes from one producer, Oak Ridge Nuclear Laboratory (ORNL) in the US. Canadian concern is that foreign needs will be met only after domestic needs, thus creating a shortage of stable isotopes in Canada. This article describes the present situation in Canada (availability and cost) of stable isotopes, the isotope enrichment techniques, and related research programs at Chalk River Nuclear Laboratories (CRNL)

  11. Molecular characterization and identification of markers for toxic and non-toxic varieties of Jatropha curcas L. using RAPD, AFLP and SSR markers.

    Science.gov (United States)

    Sudheer Pamidimarri, D V N; Singh, Sweta; Mastan, Shaik G; Patel, Jalpa; Reddy, Muppala P

    2009-07-01

    Jatropha curcas L., a multipurpose shrub has acquired significant economic importance for its seed oil which can be converted to biodiesel, is emerging as an alternative to petro-diesel. The deoiled seed cake remains after oil extraction is toxic and cannot be used as a feed despite having best nutritional contents. No quantitative and qualitative differences were observed between toxic and non-toxic varieties of J. curcas except for phorbol esters content. Development of molecular marker will enable to differentiate non-toxic from toxic variety in a mixed population and also help in improvement of the species through marker assisted breeding programs. The present investigation was undertaken to characterize the toxic and non-toxic varieties at molecular level and to develop PCR based molecular markers for distinguishing non-toxic from toxic or vice versa. The polymorphic markers were successfully identified specific to non-toxic and toxic variety using RAPD and AFLP techniques. Totally 371 RAPD, 1,442 AFLP markers were analyzed and 56 (15.09%) RAPD, 238 (16.49%) AFLP markers were found specific to either of the varieties. Genetic similarity between non-toxic and toxic verity was found to be 0.92 by RAPD and 0.90 by AFLP fingerprinting. In the present study out of 12 microsatellite markers analyzed, seven markers were found polymorphic. Among these seven, jcms21 showed homozygous allele in the toxic variety. The study demonstrated that both RAPD and AFLP techniques were equally competitive in identifying polymorphic markers and differentiating both the varieties of J. curcas. Polymorphism of SSR markers prevailed between the varieties of J. curcas. These RAPD and AFLP identified markers will help in selective cultivation of specific variety and along with SSRs these markers can be exploited for further improvement of the species through breeding and Marker Assisted Selection (MAS).

  12. Molecular distribution and compound-specific stable carbon isotopic composition of dicarboxylic acids, oxocarboxylic acids and α-dicarbonyls in PM2.5 from Beijing, China

    Directory of Open Access Journals (Sweden)

    W. Zhao

    2018-02-01

    Full Text Available This study investigates the seasonal variation, molecular distribution and stable carbon isotopic composition of diacids, oxocarboxylic acids and α-dicarbonyls to better understand the sources and formation processes of fine aerosols (PM2.5 in Beijing. The concentrations of total dicarboxylic acids varied from 110 to 2580 ng m−3, whereas oxoacids (9.50–353 ng m−3 and dicarbonyls (1.50–85.9 ng m−3 were less abundant. Oxalic acid was found to be the most abundant individual species, followed by succinic acid or occasionally by terephthalic acid (tPh, a plastic waste burning tracer. Ambient concentrations of phthalic acid (37.9 ± 27.3 ng m−3 and tPh (48.7 ± 51.1 ng m−3 were larger in winter than in other seasons, illustrating that fossil fuel combustion and plastic waste incineration contribute more to wintertime aerosols. The year-round mass concentration ratios of malonic acid to succinic acid (C3 ∕ C4 were relatively low by comparison with those in other urban aerosols and remote marine aerosols. The values were less than or equal to unity in Beijing, implying that the degree of photochemical formation of diacids in Beijing is insignificant. Moreover, strong correlation coefficients of major oxocarboxylic acids and α-dicarbonyls with nss-K+ suggest that biomass burning contributes significantly to these organic acids and related precursors. The mean δ13C value of succinic acid is the highest among all species, with values of −17.1 ± 3.9 ‰ (winter and −17.1 ± 2.0 ‰ (spring, while malonic acid is more enriched in 13C than others in autumn (−17.6 ± 4.6 ‰ and summer (−18.7 ± 4.0 ‰. The δ13C values of major species in Beijing aerosols are generally lower than those in the western North Pacific atmosphere, the downwind region, which indicates that stable carbon isotopic compositions of diacids depend on their precursor sources in Beijing. Therefore, our

  13. Molecular distribution and compound-specific stable carbon isotopic composition of dicarboxylic acids, oxocarboxylic acids and α-dicarbonyls in PM2.5 from Beijing, China

    Science.gov (United States)

    Zhao, Wanyu; Kawamura, Kimitaka; Yue, Siyao; Wei, Lianfang; Ren, Hong; Yan, Yu; Kang, Mingjie; Li, Linjie; Ren, Lujie; Lai, Senchao; Li, Jie; Sun, Yele; Wang, Zifa; Fu, Pingqing

    2018-02-01

    This study investigates the seasonal variation, molecular distribution and stable carbon isotopic composition of diacids, oxocarboxylic acids and α-dicarbonyls to better understand the sources and formation processes of fine aerosols (PM2.5) in Beijing. The concentrations of total dicarboxylic acids varied from 110 to 2580 ng m-3, whereas oxoacids (9.50-353 ng m-3) and dicarbonyls (1.50-85.9 ng m-3) were less abundant. Oxalic acid was found to be the most abundant individual species, followed by succinic acid or occasionally by terephthalic acid (tPh), a plastic waste burning tracer. Ambient concentrations of phthalic acid (37.9 ± 27.3 ng m-3) and tPh (48.7 ± 51.1 ng m-3) were larger in winter than in other seasons, illustrating that fossil fuel combustion and plastic waste incineration contribute more to wintertime aerosols. The year-round mass concentration ratios of malonic acid to succinic acid (C3 / C4) were relatively low by comparison with those in other urban aerosols and remote marine aerosols. The values were less than or equal to unity in Beijing, implying that the degree of photochemical formation of diacids in Beijing is insignificant. Moreover, strong correlation coefficients of major oxocarboxylic acids and α-dicarbonyls with nss-K+ suggest that biomass burning contributes significantly to these organic acids and related precursors. The mean δ13C value of succinic acid is the highest among all species, with values of -17.1 ± 3.9 ‰ (winter) and -17.1 ± 2.0 ‰ (spring), while malonic acid is more enriched in 13C than others in autumn (-17.6 ± 4.6 ‰) and summer (-18.7 ± 4.0 ‰). The δ13C values of major species in Beijing aerosols are generally lower than those in the western North Pacific atmosphere, the downwind region, which indicates that stable carbon isotopic compositions of diacids depend on their precursor sources in Beijing. Therefore, our study demonstrates that in addition to photochemical oxidation, high abundances of diacids

  14. Electrocatalytic hydride-forming compounds for rechageable batteries

    NARCIS (Netherlands)

    Notten, P.H.L.; Einerhand, R.E.F.

    1991-01-01

    Non-toxic intermetallic hydride-forming compounds are attractive alternatives to cadmium as the negative electrode materials in the new generation of Ni/metal hydride rechargeable batteries. High exchange currents and discharge efficiencies even at low temperatures can be achieved using highly

  15. Effect of phenolic compounds released during degradation of Coir ...

    African Journals Online (AJOL)

    MICHAEL

    www.bioline.org.br/ja. Effect of phenolic compounds released during degradation of Coir pith by ... of the culture filtrate appears to be non toxic in the tested animals @ JASEM. Coir pith is a highly ... degradation of coir pith by fungi and bacteria were already reported, ... no.1 filter paper and used as feed for the experimental ...

  16. A compounded rare-earth iron garnet single crystal exhibiting stable Faraday rotation against wavelength and temperature variation in the 1.55 μm band

    International Nuclear Information System (INIS)

    Xu, Z.C.; Huang, M.; Li Miao

    2006-01-01

    The Bi, Tb and Yb partially substituted iron garnet bulk single crystals of Tb 3- x - y Yb y Bi x Fe 5 O 12 were grown by using Bi 2 O 3 /B 2 O 3 as flux and accelerated crucible rotation technique for single-crystal growth. Faraday rotation (FR) spectra showed that the specific FR of the (Tb 0.91 Yb 1.38 Bi 0.71 )Fe 5 O 12 crystal under magnetic field at saturation was measured to be about -1617 o /cm at λ=1.55 μm, Faraday rotation wavelength coefficient (FWC, 0.009%/nm) in the wavelength range of 1.50-1.62 μm and Faraday rotation temperature coefficient (FTC, 3.92x10 -5 /K) at λ=1.55 μm were even smaller than that of YIG. It is proven that through combining two types of Bi-substituted rare-earth iron garnets with opposite FWC and FTC signs, the compound rare-earth iron garnets with low FWC and FTC may be obtained due to the compensation effect. The saturation magnetization of (Tb 0.91 Yb 1.38 Bi 0.71 ) Fe 5 O 12 crystal is 0.48x10 6 A/M and is also much smaller than that of YIG. We have found empirically that there is a simple relationship between the FR θ f (x) and Bi content x for Tb 3- x - y Yb y Bi x Fe 5 O 12 , which is given by θ f (x)=(-2759x+400) o /cm

  17. Metabolism of Seriola lalandi during Starvation as Revealed by Fatty Acid Analysis and Compound-Specific Analysis of Stable Isotopes within Amino Acids.

    Directory of Open Access Journals (Sweden)

    Fernando Barreto-Curiel

    Full Text Available Fish starvation is defined as food deprivation for a long period of time, such that physiological processes become confined to basal metabolism. Starvation provides insights in physiological processes without interference from unknown factors in digestion and nutrient absorption occurring in fed state. Juveniles of amberjack Seriola lalandi were isotopically equilibrated to a formulated diet for 60 days. One treatment consisted of fish that continued to be fed and fish in the other treatment were not fed for 35 days. The isotopic signatures prior to the beginning of and after the starvation period, for fish in the starvation and control treatments, were analysed for lipid content, fatty acid composition and isotopic analysis of bulk (EA-IRMS and of amino acids (compound specific isotope analysis, CSIA. There were three replicates for the starvation group. Fatty acid content in muscle and liver tissue before and after starvation was determined to calculate percent change. Results showed that crude lipid was the most used source of energy in most cases; the PUFAs and LC-PUFAs were highly conserved. According to the protein signature in bulk (δ15N and per amino acid (δ13C and δ15N, in muscle tissue, protein synthesis did not appear to occur substantially during starvation, whereas in liver, increases in δ13C and δ15N indicate that protein turnover occurred, probably for metabolic routing to energy-yielding processes. As a result, isotopic values of δ15N in muscle tissue do not change, whereas CSIA net change occurred in the liver tissue. During the study period of 35 days, muscle protein was largely conserved, being neither replenished from amino acid pools in the plasma and liver nor catabolized.

  18. Rate of uptake and distribution of Hg in dissolved organic carbon compounds in darkwater ecosystems by ICP-MS and enriched stable isotope spiking

    International Nuclear Information System (INIS)

    Telmer, Kevin; Dario Bermudez, Rafael; Veiga, Marcello M.; Souza, Terezinha Cid da

    2001-01-01

    The role of natural organic acids on mercury binding, transportation, net uptake rates and possibly net methylation rates will be evaluated by tracing these processes with isotope enriched mercury and ICP-MS technology. The correlation between dissolved organic matter and Hg in waters is well documented. It appears that organic acids can react with mercury residing in or emitted from different sources such as soils (particularly hydromorphic soils), laterites, natural degassing, forest fires, fuel combustion, gold mining activities, etc. to form soluble Hg-organo-complexes. The formation of these complexes is believed to greatly enhance Hg transport and be an important preliminary step in the formation of Methyl-Hg and biological uptake. The rates of these reactions and the key organic compounds involved in mercury binding will be determined by reacting isotopically-enriched Hg with samples containing a variety of concentrations and types of organic acids and subsequently analysing both reactants and organisms exposed to the reactants (bioassays) for Hg isotopes by ICP-MS. The Hg spike will allow the precise determination of rates of uptake and the most active agents of uptake. Initially, the method will be used to examine total Hg uptake and distribution but if technological limitations are overcome, this same approach can be used to determine net rates of methylation and net MeHg uptake. After the method is validated the experimental design can be altered to test the relative effects of such things as the addition of CO 2 (pH change), or adding a substrate such as Fe-Mn oxyhydroxides. The addition of synthetic materials such as mulched automobile tires, can also be tested with the goal developing a pragmatic remedial method for Hg containment. Ultimately, this research should contribute to an understanding of mercury mobilization, transport and bio-concentration mechanisms, and provide a basis for developing management and treatment strategies. Emphasis will be

  19. Microcystin uptake and biochemical responses in the freshwater clam Corbicula leana P. exposed to toxic and non-toxic Microcystis aeruginosa: Evidence of tolerance to cyanotoxins.

    Science.gov (United States)

    Pham, Thanh-Luu; Shimizu, Kazuya; Dao, Thanh-Son; Hong-Do, Lan-Chi; Utsumi, Motoo

    2015-01-01

    We investigated the accumulation and adverse effects of toxic and non-toxic Microcystis in the edible clam Corbicula leana . Treated clams were exposed to toxic Microcystis at 100 μg of MC (microcystin)-LR eq  L -1 for 10 days. The experimental organism was then placed in toxin-free water and fed on non-toxic Microcystis for the following 10 days for depuration. Filtering rates (FRs) by C. leana of toxic and non-toxic Microcystis and of the green alga Chlorella vulgaris as a control were estimated. Adverse effects were evaluated though the activity of catalase (CAT), superoxide dismutase (SOD) and glutathione S-transferase (GST). Clam accumulated MCs (up to 12.7 ± 2.5 μg g -1 dry weight (DW) of free MC and 4.2 ± 0.6 μg g -1 DW of covalently bound MC). Our results suggest that although both toxic and non-toxic cyanobacteria caused adverse effects by inducing the detoxification and antioxidant defense system, the clam was quite resistant to cyanotoxins. The estimated MC concentration in C. leana was far beyond the World Health Organization's (WHO) provisional tolerable daily intake (0.04 μg kg -1  day -1 ), suggesting that consuming clams harvested during cyanobacterial blooms carries a high health risk.

  20. Microcystin uptake and biochemical responses in the freshwater clam Corbicula leana P. exposed to toxic and non-toxic Microcystis aeruginosa: Evidence of tolerance to cyanotoxins

    Directory of Open Access Journals (Sweden)

    Thanh-Luu Pham

    2015-01-01

    Full Text Available We investigated the accumulation and adverse effects of toxic and non-toxic Microcystis in the edible clam Corbicula leana. Treated clams were exposed to toxic Microcystis at 100 μg of MC (microcystin-LReq L−1 for 10 days. The experimental organism was then placed in toxin-free water and fed on non-toxic Microcystis for the following 10 days for depuration. Filtering rates (FRs by C. leana of toxic and non-toxic Microcystis and of the green alga Chlorella vulgaris as a control were estimated. Adverse effects were evaluated though the activity of catalase (CAT, superoxide dismutase (SOD and glutathione S-transferase (GST. Clam accumulated MCs (up to 12.7 ± 2.5 μg g−1 dry weight (DW of free MC and 4.2 ± 0.6 μg g−1 DW of covalently bound MC. Our results suggest that although both toxic and non-toxic cyanobacteria caused adverse effects by inducing the detoxification and antioxidant defense system, the clam was quite resistant to cyanotoxins. The estimated MC concentration in C. leana was far beyond the World Health Organization's (WHO provisional tolerable daily intake (0.04 μg kg−1 day−1, suggesting that consuming clams harvested during cyanobacterial blooms carries a high health risk.

  1. Induction and transfer of resistance to poisoning by Amorimia pubiflora in sheep with non-toxic doses of the plant and ruminal content

    Science.gov (United States)

    Amorimia pubiflora (Malpighiaceae), which contains sodium monofluoroacetate (MFA) is the main cause of “sudden death” in cattle in the Brazilian state of Mato Grosso. This research investigated the induction of resistance to the poisoning in sheep by the continuous administration of non-toxic doses ...

  2. A self-adjustable four-point probing system using polymeric three dimensional coils and non-toxic liquid metal

    Energy Technology Data Exchange (ETDEWEB)

    Oyunbaatar, Nomin-Erdene; Choi, Young Soo; Lee, Dong-Weon, E-mail: mems@jnu.ac.kr [MEMS and Nanotechnology Laboratory, School of Mechanical Engineering, Chonnam National University, Gwangju 500757 (Korea, Republic of)

    2015-12-15

    This paper describes a self-adjustable four-point probe (S4PP) system with a square configuration. The S4PP system consists of 3D polymer coil springs for the independent operation of each tungsten (W) probe, microfluidic channels filled with a nontoxic liquid metal, and a LabView-based control system. The 3D coil springs made by PMMA are fabricated with a 3D printer and are positioned in a small container filled with the non-toxic liquid metal. This unique configuration allows independent self-adjustment of the probe heights for precise measurements of the electrical properties of both flexible and large-step-height microsamples. The feasibility of the fabricated S4PP system is evaluated by measuring the specific resistance of Cr and Au thin films deposited on silicon wafers. The system is then employed to evaluate the electrical properties of a Au thin film deposited onto a flexible and easily breakable silicon diaphragm (spring constant: ∼3.6 × 10{sup −5} N/m). The resistance of the Cr thin films (thickness: 450 nm) with step heights of 60 and 90 μm is also successfully characterized. These experimental results indicate that the proposed S4PP system can be applied to common metals and semiconductors as well as flexible and large-step-height samples.

  3. A self-adjustable four-point probing system using polymeric three dimensional coils and non-toxic liquid metal

    International Nuclear Information System (INIS)

    Oyunbaatar, Nomin-Erdene; Choi, Young Soo; Lee, Dong-Weon

    2015-01-01

    This paper describes a self-adjustable four-point probe (S4PP) system with a square configuration. The S4PP system consists of 3D polymer coil springs for the independent operation of each tungsten (W) probe, microfluidic channels filled with a nontoxic liquid metal, and a LabView-based control system. The 3D coil springs made by PMMA are fabricated with a 3D printer and are positioned in a small container filled with the non-toxic liquid metal. This unique configuration allows independent self-adjustment of the probe heights for precise measurements of the electrical properties of both flexible and large-step-height microsamples. The feasibility of the fabricated S4PP system is evaluated by measuring the specific resistance of Cr and Au thin films deposited on silicon wafers. The system is then employed to evaluate the electrical properties of a Au thin film deposited onto a flexible and easily breakable silicon diaphragm (spring constant: ∼3.6 × 10"−"5 N/m). The resistance of the Cr thin films (thickness: 450 nm) with step heights of 60 and 90 μm is also successfully characterized. These experimental results indicate that the proposed S4PP system can be applied to common metals and semiconductors as well as flexible and large-step-height samples.

  4. Radionuclides, stable isotopes, inorganic constituents, and organic compounds in water from selected wells and springs from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman area, Idaho, 1993

    Science.gov (United States)

    Bartholomay, Roy C.; Edwards, Daniel D.; Campbell, Linford J.

    1994-01-01

    The U.S. Geological Survey and the Idaho Department of Water Resources, in response to a request from the U.S. Department of Energy, sampled 19 sites as part of a long-term project to monitor water quality of the Snake River Plain aquifer from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman area. Water samples were collected and analyzed for selected radionuclides, stable isotopes, inorganic constituents, and organic compounds. The samples were collected from seven irrigation wells, four domestic wells, two springs, one stock well, three dairy wells, one observation well, and one commercial well. Two quality assurance samples also were collected and analyzed. None of the radionuclides, inorganic constituents, or organic compounds exceeded the established maximum contaminant levels for drinking water. Most of the radionuclide and inorganic constituent concen- trations exceeded their respective laboratory reporting levels. All samples analyzed for surfactants and dissolved organic carbon had concentrations that exceeded their reporting level. Ethylbenzene concentrations exceeded the reporting level in one water sample.

  5. Non-Toxic Buffer Layers in Flexible Cu(In,GaSe2 Photovoltaic Cell Applications with Optimized Absorber Thickness

    Directory of Open Access Journals (Sweden)

    Md. Asaduzzaman

    2017-01-01

    Full Text Available Absorber layer thickness gradient in Cu(In1−xGaxSe2 (CIGS based solar cells and several substitutes for typical cadmium sulfide (CdS buffer layers, such as ZnS, ZnO, ZnS(O,OH, Zn1−xSnxOy (ZTO, ZnSe, and In2S3, have been analyzed by a device emulation program and tool (ADEPT 2.1 to determine optimum efficiency. As a reference type, the CIGS cell with CdS buffer provides a theoretical efficiency of 23.23% when the optimum absorber layer thickness was determined as 1.6 μm. It is also observed that this highly efficient CIGS cell would have an absorber layer thickness between 1 μm and 2 μm whereas the optimum buffer layer thickness would be within the range of 0.04–0.06 μm. Among all the cells with various buffer layers, the best energy conversion efficiency of 24.62% has been achieved for the ZnO buffer layer based cell. The simulation results with ZnS and ZnO based buffer layer materials instead of using CdS indicate that the cell performance would be better than that of the CdS buffer layer based cell. Although the cells with ZnS(O,OH, ZTO, ZnSe, and In2S3 buffer layers provide slightly lower efficiencies than that of the CdS buffer based cell, the use of these materials would not be deleterious for the environment because of their non-carcinogenic and non-toxic nature.

  6. Comparative Transcriptome Analysis of a Toxin-Producing Dinoflagellate Alexandrium catenella and Its Non-Toxic Mutant

    Directory of Open Access Journals (Sweden)

    Yong Zhang

    2014-11-01

    Full Text Available The dinoflagellates and cyanobacteria are two major kingdoms of life producing paralytic shellfish toxins (PSTs, a large group of neurotoxic alkaloids causing paralytic shellfish poisonings around the world. In contrast to the well elucidated PST biosynthetic genes in cyanobacteria, little is known about the dinoflagellates. This study compared transcriptome profiles of a toxin-producing dinoflagellate, Alexandrium catenella (ACHK-T, and its non-toxic mutant form (ACHK-NT using RNA-seq. All clean reads were assembled de novo into a total of 113,674 unigenes, and 66,812 unigenes were annotated in the known databases. Out of them, 35 genes were found to express differentially between the two strains. The up-regulated genes in ACHK-NT were involved in photosynthesis, carbon fixation and amino acid metabolism processes, indicating that more carbon and energy were utilized for cell growth. Among the down-regulated genes, expression of a unigene assigned to the long isoform of sxtA, the initiator of toxin biosynthesis in cyanobacteria, was significantly depressed, suggesting that this long transcript of sxtA might be directly involved in toxin biosynthesis and its depression resulted in the loss of the ability to synthesize PSTs in ACHK-NT. In addition, 101 putative homologs of 12 cyanobacterial sxt genes were identified, and the sxtO and sxtZ genes were identified in dinoflagellates for the first time. The findings of this study should shed light on the biosynthesis of PSTs in the dinoflagellates.

  7. Effects of diuretics on iodine uptake in non-toxic goitre: comparison with low-iodine diet

    Energy Technology Data Exchange (ETDEWEB)

    Kapucu, L.Ozlem; Azizoglu, Firat [Department of Nuclear Medicine, Gazi University, Ankara (Turkey); Ayvaz, Goksun; Karakoc, Ayhan [Department of Endocrinology, Gazi University, Ankara (Turkey)

    2003-09-01

    Low-iodine diet has been employed to achieve iodine depletion prior to radioiodine (RI) therapy. However, treatment with diuretics may be more effective than low-iodine diet in causing iodine depletion and subsequent increase in RI uptake by the thyroid. Fifty-five patients with non-toxic goitre were given 0.20 MBq RI p.o. on the first day of the study and thyroid uptake was measured. In 15 patients, a low-iodine diet was started and continued for 14 days. The remaining 40 patients received furosemide 40 mg/day orally for 5 days with an unrestricted diet. On the 15th day of the study, all patients were given 0.20 MBq RI p.o. and thyroid RI uptake was measured again. Additionally, 24-h urinary iodine excretion and RI clearance were measured on the 1st and 6th days in 21 patients from the furosemide group and on the 1st and 15th days in eight patients from the diet group. Furosemide administration led to a 58.40% increase in iodine uptake over the baseline value, which was significantly higher than the increase caused by low-iodine diet (17.22%) (P<0.0001). Urinary excretion of RI decreased in both groups similarly (furosemide, 29.45%; low-iodine diet, 21.06%; P=0.33). Iodine clearance also decreased in each group similarly (10.61% vs 7.53%, P=0.53). Treatment with furosemide prior to administration of RI increases the uptake of RI by the thyroid more effectively than does low-iodine diet. (orig.)

  8. Numerical simulation of ammonium dinitramide (ADN)-based non-toxic aerospace propellant decomposition and combustion in a monopropellant thruster

    International Nuclear Information System (INIS)

    Zhang, Tao; Li, Guoxiu; Yu, Yusong; Sun, Zuoyu; Wang, Meng; Chen, Jun

    2014-01-01

    Highlights: • Decomposition and combustion process of ADN-based thruster are studied. • Distribution of droplets is obtained during the process of spray hit on wire mesh. • Two temperature models are adopted to describe the heat transfer in porous media. • The influences brought by different mass flux and porosity are studied. - Abstract: Ammonium dinitramide (ADN) monopropellant is currently the most promising among all ‘green propellants’. In this paper, the decomposition and combustion process of liquid ADN-based ternary mixtures for propulsion are numerically studied. The R–R distribution model is used to study the initial boundary conditions of droplet distribution resulting from spray hit on a wire mesh based on PDA experiment. To simulate the heat-transfer characteristics between the gas–solid phases, a two-temperature porous medium model in a catalytic bed is used. An 11-species and 7-reactions chemistry model is used to study the catalytic and combustion processes. The final distribution of temperature, pressure, and other kinds of material component concentrations are obtained using the ADN thruster. The results of simulation conducted in the present study are well agree with previous experimental data, and the demonstration of the ADN thruster confirms that a good steady-state operation is achieved. The effects of spray inlet mass flux and porosity on monopropellant thruster performance are analyzed. The numerical results further show that a larger inlet mass flux results in better thruster performance and a catalytic bed porosity value of 0.5 can exhibit the best thruster performance. These findings can serve as a key reference for designing and testing non-toxic aerospace monopropellant thrusters

  9. Unpredictably Stable

    DEFF Research Database (Denmark)

    Failla, Virgilio; Melillo, Francesca; Reichstein, Toke

    2014-01-01

    Is entrepreneurship a more stable career choice for high employment turnover individuals? We find that a transition to entrepreneurship induces a shift towards stayer behavior and identify job matching, job satisfaction and lock-in effects as main drivers. These findings have major implications...

  10. Minute synthesis of extremely stable gold nanoparticles.

    Science.gov (United States)

    Zhou, Min; Wang, Baoxiang; Rozynek, Zbigniew; Xie, Zhaohui; Fossum, Jon Otto; Yu, Xiaofeng; Raaen, Steinar

    2009-12-16

    We describe a rapid environmentally friendly wet-chemical approach to synthesize extremely stable non-toxic, biocompatible, water-soluble monodispersed gold nanoparticles (AuNPs) in one step at room temperature. The particles have been successfully achieved in just a few minutes by merely adding sodium hydroxide (NaOH) acting as an initiator for the reduction of HAuCl(4) in aqueous solution in the presence of polyvinylpyrrolidone (PVP) without the use of any reducing agent. It is also proved to be highly efficient for the preparation of AuNPs with controllable sizes. The AuNPs show remarkable stability in water media with high concentrations of salt, various buffer solutions and physiological conditions in biotechnology and biomedicine. Moreover, the AuNPs are also non-toxic at high concentration (100 microM). Therefore, it provides great opportunities to use these AuNPs for biotechnology and biomedicine. This new approach also involved several green chemistry concepts, such as the selection of environmentally benign reagents and solvents, without energy consumption, and less reaction time.

  11. Minute synthesis of extremely stable gold nanoparticles

    International Nuclear Information System (INIS)

    Zhou Min; Wang Baoxiang; Rozynek, Zbigniew; Xie Zhaohui; Fossum, Jon Otto; Yu Xiaofeng; Raaen, Steinar

    2009-01-01

    We describe a rapid environmentally friendly wet-chemical approach to synthesize extremely stable non-toxic, biocompatible, water-soluble monodispersed gold nanoparticles (AuNPs) in one step at room temperature. The particles have been successfully achieved in just a few minutes by merely adding sodium hydroxide (NaOH) acting as an initiator for the reduction of HAuCl 4 in aqueous solution in the presence of polyvinylpyrrolidone (PVP) without the use of any reducing agent. It is also proved to be highly efficient for the preparation of AuNPs with controllable sizes. The AuNPs show remarkable stability in water media with high concentrations of salt, various buffer solutions and physiological conditions in biotechnology and biomedicine. Moreover, the AuNPs are also non-toxic at high concentration (100 μM). Therefore, it provides great opportunities to use these AuNPs for biotechnology and biomedicine. This new approach also involved several green chemistry concepts, such as the selection of environmentally benign reagents and solvents, without energy consumption, and less reaction time.

  12. Review on Molecular Mechanisms of Antifouling Compounds: An Update since 2012.

    Science.gov (United States)

    Chen, Lianguo; Qian, Pei-Yuan

    2017-08-28

    Better understanding of the mechanisms of antifouling compounds is recognized to be of high value in establishing sensitive biomarkers, allowing the targeted optimization of antifouling compounds and guaranteeing environmental safety. Despite vigorous efforts to find new antifouling compounds, information about the mechanisms of antifouling is still scarce. This review summarizes the progress into understanding the molecular mechanisms underlying antifouling activity since 2012. Non-toxic mechanisms aimed at specific targets, including inhibitors of transmembrane transport, quorum sensing inhibitors, neurotransmission blockers, adhesive production/release inhibitors and enzyme/protein inhibitors, are put forward for natural antifouling products or shelf-stable chemicals. Several molecular targets show good potential for use as biomarkers in future mechanistic screening, such as acetylcholine esterase for neurotransmission, phenoloxidase/tyrosinase for the formation of adhesive plaques, N -acyl homoserine lactone for quorum sensing and intracellular Ca 2+ levels as second messenger. The studies on overall responses to challenges by antifoulants can be categorized as general targets, including protein expression/metabolic activity regulators, oxidative stress inducers, neurotransmission blockers, surface modifiers, biofilm inhibitors, adhesive production/release inhibitors and toxic killing. Given the current situation and the knowledge gaps regarding the development of alternative antifoulants, a basic workflow is proposed that covers the indispensable steps, including preliminary mechanism- or bioassay-guided screening, evaluation of environmental risks, field antifouling performance, clarification of antifouling mechanisms and the establishment of sensitive biomarkers, which are combined to construct a positive feedback loop.

  13. Stable particles

    International Nuclear Information System (INIS)

    Samios, N.P.

    1993-01-01

    I have been asked to review the subject of stable particles, essentially the particles that eventually comprised the meson and baryon octets. with a few more additions -- with an emphasis on the contributions made by experiments utilizing the bubble chamber technique. In this activity, much work had been done by the photographic emulsion technique and cloud chambers-exposed to cosmic rays as well as accelerator based beams. In fact, many if not most of the stable particles were found by these latter two techniques, however, the forte of the bubble chamber (coupled with the newer and more powerful accelerators) was to verify, and reinforce with large statistics, the existence of these states, to find some of the more difficult ones, mainly neutrals and further to elucidate their properties, i.e., spin, parity, lifetimes, decay parameters, etc

  14. Uses of stable isotopes

    International Nuclear Information System (INIS)

    Axente, Damian

    1998-01-01

    The most important fields of stable isotope use with examples are presented. These are: 1. Isotope dilution analysis: trace analysis, measurements of volumes and masses; 2. Stable isotopes as tracers: transport phenomena, environmental studies, agricultural research, authentication of products and objects, archaeometry, studies of reaction mechanisms, structure and function determination of complex biological entities, studies of metabolism, breath test for diagnostic; 3. Isotope equilibrium effects: measurement of equilibrium effects, investigation of equilibrium conditions, mechanism of drug action, study of natural processes, water cycle, temperature measurements; 4. Stable isotope for advanced nuclear reactors: uranium nitride with 15 N as nuclear fuel, 157 Gd for reactor control. In spite of some difficulties of stable isotope use, particularly related to the analytical techniques, which are slow and expensive, the number of papers reporting on this subject is steadily growing as well as the number of scientific meetings organized by International Isotope Section and IAEA, Gordon Conferences, and regional meeting in Germany, France, etc. Stable isotope application development on large scale is determined by improving their production technologies as well as those of labeled compound and the analytical techniques. (author)

  15. High dietary quality of non-toxic cyanobacteria for a benthic grazer and its implications for the control of cyanobacterial biofilms

    OpenAIRE

    Groendahl, Sophie; Fink, Patrick

    2017-01-01

    Background Mass occurrences of cyanobacteria frequently cause detrimental effects to the functioning of aquatic ecosystems. Consequently, attempts haven been made to control cyanobacterial blooms through naturally co-occurring herbivores. Control of cyanobacteria through herbivores often appears to be constrained by their low dietary quality, rather than by the possession of toxins, as also non-toxic cyanobacteria are hardly consumed by many herbivores. It was thus hypothesized that the consu...

  16. A low-cost non-toxic post-growth activation step for CdTe solar cells

    Science.gov (United States)

    Major, J. D.; Treharne, R. E.; Phillips, L. J.; Durose, K.

    2014-07-01

    Cadmium telluride, CdTe, is now firmly established as the basis for the market-leading thin-film solar-cell technology. With laboratory efficiencies approaching 20 per cent, the research and development targets for CdTe are to reduce the cost of power generation further to less than half a US dollar per watt (ref. 2) and to minimize the environmental impact. A central part of the manufacturing process involves doping the polycrystalline thin-film CdTe with CdCl2. This acts to form the photovoltaic junction at the CdTe/CdS interface and to passivate the grain boundaries, making it essential in achieving high device efficiencies. However, although such doping has been almost ubiquitous since the development of this processing route over 25 years ago, CdCl2 has two severe disadvantages; it is both expensive (about 30 cents per gram) and a water-soluble source of toxic cadmium ions, presenting a risk to both operators and the environment during manufacture. Here we demonstrate that solar cells prepared using MgCl2, which is non-toxic and costs less than a cent per gram, have efficiencies (around 13%) identical to those of a CdCl2-processed control group. They have similar hole densities in the active layer (9 × 1014 cm-3) and comparable impurity profiles for Cl and O, these elements being important p-type dopants for CdTe thin films. Contrary to expectation, CdCl2-processed and MgCl2-processed solar cells contain similar concentrations of Mg; this is because of Mg out-diffusion from the soda-lime glass substrates and is not disadvantageous to device performance. However, treatment with other low-cost chlorides such as NaCl, KCl and MnCl2 leads to the introduction of electrically active impurities that do compromise device performance. Our results demonstrate that CdCl2 may simply be replaced directly with MgCl2 in the existing fabrication process, thus both minimizing the environmental risk and reducing the cost of CdTe solar-cell production.

  17. Breast cancer stem-like cells are inhibited by a non-toxic aryl hydrocarbon receptor agonist.

    Directory of Open Access Journals (Sweden)

    Gérald J Prud'homme

    2010-11-01

    Full Text Available Cancer stem cells (CSCs have increased resistance to cancer chemotherapy. They can be enriched as drug-surviving CSCs (D-CSCs by growth with chemotherapeutic drugs, and/or by sorting of cells expressing CSC markers such as aldehyde dehydrogenase-1 (ALDH. CSCs form colonies in agar, mammospheres in low-adherence cultures, and tumors following xenotransplantation in Scid mice. We hypothesized that tranilast, a non-toxic orally active drug with anti-cancer activities, would inhibit breast CSCs.We examined breast cancer cell lines or D-CSCs generated by growth of these cells with mitoxantrone. Tranilast inhibited colony formation, mammosphere formation and stem cell marker expression. Mitoxantrone-selected cells were enriched for CSCs expressing stem cell markers ALDH, c-kit, Oct-4, and ABCG2, and efficient at forming mammospheres. Tranilast markedly inhibited mammosphere formation by D-CSCs and dissociated formed mammospheres, at pharmacologically relevant concentrations. It was effective against D-CSCs of both HER-2+ and triple-negative cell lines. Tranilast was also effective in vivo, since it prevented lung metastasis in mice injected i.v. with triple-negative (MDA-MB-231 mitoxantrone-selected cells. The molecular targets of tranilast in cancer have been unknown, but here we demonstrate it is an aryl hydrocarbon receptor (AHR agonist and this plays a key role. AHR is a transcription factor activated by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, polycyclic aromatic hydrocarbons and other ligands. Tranilast induced translocation of the AHR to the nucleus and stimulated CYP1A1 expression (a marker of AHR activation. It inhibited binding of the AHR to CDK4, which has been linked to cell-cycle arrest. D-CSCs expressed higher levels of the AHR than other cells. Knockdown of the AHR with siRNA, or blockade with an AHR antagonist, entirely abrogated the anti-proliferative and anti-mammosphere activity of tranilast. Thus, the anti-cancer effects of

  18. Forensic analysis of explosives using isotope ratio mass spectrometry (IRMS)--part 2: forensic inter-laboratory trial: bulk carbon and nitrogen stable isotopes in a range of chemical compounds (Australia and New Zealand).

    Science.gov (United States)

    Benson, Sarah J; Lennard, Christopher J; Maynard, Philip; Hill, David M; Andrew, Anita S; Neal, Ken; Stuart-Williams, Hilary; Hope, Janet; Walker, G Stewart; Roux, Claude

    2010-01-01

    Comparability of data over time and between laboratories is a key issue for consideration in the development of global databases, and more broadly for quality assurance in general. One mechanism that can be utilized for evaluating traceability is an inter-laboratory trial. This paper addresses an inter-laboratory trial conducted across a number of Australian and New Zealand isotope ratio mass spectrometry (IRMS) laboratories. The main objective of this trial was to determine whether IRMS laboratories in these countries would record comparable values for the distributed samples. Four carbon containing and four nitrogen containing compounds were distributed to seven laboratories in Australia and one in New Zealand. The laboratories were requested to analyze the samples using their standard procedures. The data from each laboratory was evaluated collectively using International Standard ISO 13528 (Statistical methods for use in proficiency testing by inter-laboratory comparisons). "Warning signals" were raised against one participant in this trial. "Action signals" requiring corrective action were raised against four participants. These participants reviewed the data and possible sources for the discrepancies. This inter-laboratory trial was successful in providing an initial snapshot of the potential for traceability between the participating laboratories. The statistical methods described in this article could be used as a model for others needing to evaluate stable isotope results derived from multiple laboratories, e.g., inter-laboratory trials/proficiency testing. Ongoing trials will be conducted to improve traceability across the Australian and New Zealand IRMS community.

  19. Stable isotopes

    International Nuclear Information System (INIS)

    Brazier, J.L.; Guinamant, J.L.

    1995-01-01

    According to the progress which has been realised in the technology of separating and measuring isotopes, the stable isotopes are used as preferable 'labelling elements' for big number of applications. The isotopic composition of natural products shows significant variations as a result of different reasons like the climate, the seasons, or their geographic origins. So, it was proved that the same product has a different isotopic composition of alimentary and agriculture products. It is also important in detecting the pharmacological and medical chemicals. This review article deals with the technology, like chromatography and spectrophotometry, adapted to this aim, and some important applications. 17 refs. 6 figs

  20. Stable Tetraquarks

    Energy Technology Data Exchange (ETDEWEB)

    Quigg, Chris [Fermilab

    2018-04-13

    For very heavy quarks, relations derived from heavy-quark symmetry imply novel narrow doubly heavy tetraquark states containing two heavy quarks and two light antiquarks. We predict that double-beauty states will be stable against strong decays, whereas the double-charm states and mixed beauty+charm states will dissociate into pairs of heavy-light mesons. Observing a new double-beauty state through its weak decays would establish the existence of tetraquarks and illuminate the role of heavy color-antitriplet diquarks as hadron constituents.

  1. Stable beams

    CERN Multimedia

    2015-01-01

    Stable beams: two simple words that carry so much meaning at CERN. When LHC page one switched from "squeeze" to "stable beams" at 10.40 a.m. on Wednesday, 3 June, it triggered scenes of jubilation in control rooms around the CERN sites, as the LHC experiments started to record physics data for the first time in 27 months. This is what CERN is here for, and it’s great to be back in business after such a long period of preparation for the next stage in the LHC adventure.   I’ve said it before, but I’ll say it again. This was a great achievement, and testimony to the hard and dedicated work of so many people in the global CERN community. I could start to list the teams that have contributed, but that would be a mistake. Instead, I’d simply like to say that an achievement as impressive as running the LHC – a machine of superlatives in every respect – takes the combined effort and enthusiasm of everyone ...

  2. High concentrations of protein test substances may have non-toxic effects on Daphnia magna: implications for regulatory study designs and ecological risk assessments for GM crops.

    Science.gov (United States)

    Raybould, Alan; Burns, Andrea; Hamer, Mick

    2014-01-01

    Laboratory testing for possible adverse effects of insecticidal proteins on non-target organisms (NTOs) is an important part of many ecological risk assessments for regulatory decision-making about the cultivation of insect-resistant genetically modified (IRGM) crops. To increase confidence in the risk assessments, regulatory guidelines for effects testing specify that representative surrogate species for NTOs are exposed to concentrations of insecticidal proteins that are in excess of worst-case predicted exposures in the field. High concentrations in effects tests are achieved by using protein test substances produced in microbes, such as Escherichia coli. In a study that exposed Daphnia magna to a single high concentration of a microbial test substance containing Vip3Aa20, the insecticidal protein in MIR162 maize, small reductions in growth were observed. These effects were surprising as many other studies strongly suggest that the activity of Vip3Aa20 is limited to Lepidoptera. A plausible explanation for the effect on growth is that high concentrations of test substance have a non-toxic effect on Daphnia, perhaps by reducing its feeding rate. A follow-up study tested that hypothesis by exposing D. magna to several concentrations of Vip3Aa20, and a high concentration of a non-toxic protein, bovine serum albumin (BSA). Vip3Aa20 and BSA had sporadic effects on the reproduction and growth of D. magna. The pattern of the effects suggests that they result from non-toxic effects of high concentrations of protein, and not from toxicity. The implications of these results for regulatory NTO effects testing and ERA of IRGM crops are discussed.

  3. A high throughput live transparent animal bioassay to identify non-toxic small molecules or genes that regulate vertebrate fat metabolism for obesity drug development

    Directory of Open Access Journals (Sweden)

    Woollett Laura A

    2008-08-01

    Full Text Available Abstract Background The alarming rise in the obesity epidemic and growing concern for the pathologic consequences of the metabolic syndrome warrant great need for development of obesity-related pharmacotherapeutics. The search for such therapeutics is severely limited by the slow throughput of animal models of obesity. Amenable to placement into a 96 well plate, zebrafish larvae have emerged as one of the highest throughput vertebrate model organisms for performing small molecule screens. A method for visually identifying non-toxic molecular effectors of fat metabolism using a live transparent vertebrate was developed. Given that increased levels of nicotinamide adenine dinucleotide (NAD via deletion of CD38 have been shown to prevent high fat diet induced obesity in mice in a SIRT-1 dependent fashion we explored the possibility of directly applying NAD to zebrafish. Methods Zebrafish larvae were incubated with daily refreshing of nile red containing media starting from a developmental stage of equivalent fat content among siblings (3 days post-fertilization, dpf and continuing with daily refreshing until 7 dpf. Results PPAR activators, beta-adrenergic agonists, SIRT-1 activators, and nicotinic acid treatment all caused predicted changes in fat, cholesterol, and gene expression consistent with a high degree of evolutionary conservation of fat metabolism signal transduction extending from man to zebrafish larvae. All changes in fat content were visually quantifiable in a relative fashion using live zebrafish larvae nile red fluorescence microscopy. Resveratrol treatment caused the greatest and most consistent loss of fat content. The resveratrol tetramer Vaticanol B caused loss of fat equivalent in potency to resveratrol alone. Significantly, the direct administration of NAD decreased fat content in zebrafish. Results from knockdown of a zebrafish G-PCR ortholog previously determined to decrease fat content in C. elegans support that future GPR

  4. Stable agents for imaging investigations

    International Nuclear Information System (INIS)

    Tofe, A.J.

    1976-01-01

    This invention concerns highly stable compounds useful in preparing technetium 99m based scintiscanning exploration agents. The compounds of this invention include a pertechnetate reducing agent or a solution of oxidized pertechnetate and an efficient proportion, sufficient to stabilize the compounds in the presence of oxygen and of radiolysis products, of ascorbic acid or a pharmaceutically acceptable salt or ester of this acid. The invention also concerns a perfected process for preparing a technetium based exploration agent, consisting in codissolving the ascorbic acid or a pharmaceutically acceptable salt or ester of such an acid and a pertechnetate reducing agent in a solution of oxidized pertechnetate [fr

  5. Synthesis of non-toxic As and Cr nanoparticles through redox activity of highly flexible layered coordination polymer of Ni(II).

    Science.gov (United States)

    Agarwal, Rashmi A

    2018-03-09

    A simple method for the sequestration of As(III) and Cr(VI) from water has been demonstrated by utilizing a highly flexible porous coordination polymer (PCP) of Ni(II) in its as synthesized form or without solvent removal. This PCP reduces the high toxicity of As(III) and Cr(VI) ions into non-toxic As(0) and Cr/Cr 2 O 3 /CrO 2 (zero, tri and tetravalent) nanoparticles (NPs) within its pores, and this is characterized by powder x-ray diffraction, x-ray photoelectron spectroscopy and high-resolution transmission electron microscopy analysis. The high functionality of this polymer is due to the presence of monodentate carboxylate groups of a benzenetricarboxylate linker, which provide anchoring sites to the metal ions of the metal precursors. Due to the highly oxidising nature of these toxic ions, a redox reaction takes place between the framework metal ions and toxic metal ions, which is explained by an electron paramagnetic resonance study. This is the first report to synthesize non-toxic, as well as useful, NPs of As and Cr from their highly toxic ions within the cavities of a PCP for remediation of the toxic waste stream and contaminated waste water.

  6. Non-Toxic Metabolic Management of Metastatic Cancer in VM Mice: Novel Combination of Ketogenic Diet, Ketone Supplementation, and Hyperbaric Oxygen Therapy.

    Directory of Open Access Journals (Sweden)

    A M Poff

    Full Text Available The Warburg effect and tumor hypoxia underlie a unique cancer metabolic phenotype characterized by glucose dependency and aerobic fermentation. We previously showed that two non-toxic metabolic therapies - the ketogenic diet with concurrent hyperbaric oxygen (KD+HBOT and dietary ketone supplementation - could increase survival time in the VM-M3 mouse model of metastatic cancer. We hypothesized that combining these therapies could provide an even greater therapeutic benefit in this model. Mice receiving the combination therapy demonstrated a marked reduction in tumor growth rate and metastatic spread, and lived twice as long as control animals. To further understand the effects of these metabolic therapies, we characterized the effects of high glucose (control, low glucose (LG, ketone supplementation (βHB, hyperbaric oxygen (HBOT, or combination therapy (LG+βHB+HBOT on VM-M3 cells. Individually and combined, these metabolic therapies significantly decreased VM-M3 cell proliferation and viability. HBOT, alone or in combination with LG and βHB, increased ROS production in VM-M3 cells. This study strongly supports further investigation into this metabolic therapy as a potential non-toxic treatment for late-stage metastatic cancers.

  7. Synthesis of non-toxic As and Cr nanoparticles through redox activity of highly flexible layered coordination polymer of Ni(II)

    Science.gov (United States)

    Agarwal, Rashmi A.

    2018-03-01

    A simple method for the sequestration of As(III) and Cr(VI) from water has been demonstrated by utilizing a highly flexible porous coordination polymer (PCP) of Ni(II) in its as synthesized form or without solvent removal. This PCP reduces the high toxicity of As(III) and Cr(VI) ions into non-toxic As(0) and Cr/Cr2O3/CrO2 (zero, tri and tetravalent) nanoparticles (NPs) within its pores, and this is characterized by powder x-ray diffraction, x-ray photoelectron spectroscopy and high-resolution transmission electron microscopy analysis. The high functionality of this polymer is due to the presence of monodentate carboxylate groups of a benzenetricarboxylate linker, which provide anchoring sites to the metal ions of the metal precursors. Due to the highly oxidising nature of these toxic ions, a redox reaction takes place between the framework metal ions and toxic metal ions, which is explained by an electron paramagnetic resonance study. This is the first report to synthesize non-toxic, as well as useful, NPs of As and Cr from their highly toxic ions within the cavities of a PCP for remediation of the toxic waste stream and contaminated waste water.

  8. Optoelectronic and Photovoltaic Properties of the Air-Stable Organohalide Semiconductor (CH 3 NH 3 ) 3 Bi 2 I 9

    KAUST Repository

    Abulikemu, Mutalifu

    2016-07-14

    Lead halide perovskite materials have shown excellent optoelectronic as well as photovoltaic properties. However, the presence of lead and the chemical instability relegate lead halide perovskites to research applications only. Here, we investigate an emerging lead-free and air stable compound (CH3NH3)3Bi2I9 as a non-toxic potential alternative to lead halide perovskites. We have synthesized thin films, powders and millimeter-scale single crystals of (CH3NH3)3Bi2I9 and investigated their structural and optoelectronic properties. We demonstrate that the degree of crystallinity strongly affects the optoelectronic properties of the material, resulting in significantly different band gaps in polycrystalline thin films and single crystals. Surface photovoltage spectroscopy reveals outstanding photocharge generation in the visible (<700 nm), while transient absorption spectroscopy and space charge limited current measurements point to a long exciton lifetime and a high carrier mobility, respectively, similar to lead halide perovskites, pointing to the remarkable potential of this semiconductor. Photovoltaic devices fabricated using this material yield low power conversion efficiency (PCE) to date, but the PCE is expected to rise with improvements in thin film processing and device engineering.

  9. Development of SCAR marker specific to non-toxic Jatropha curcas L. and designing a novel multiplexing PCR along with nrDNA ITS primers to circumvent the false negative detection

    KAUST Repository

    Mastan, Shaik G.

    2011-05-10

    Jatropha curcas L., a multipurpose shrub, has acquired significant economic importance for its seed oil which can be converted to biodiesel an emerging alternative to petro-diesel. In addition to the commercial value, it is also having medicinal and even high nutritional value to use as animal fodder which is limited due to the toxicity. Development of molecular marker will enable to differentiate non-toxic from toxic variety of J. curcas in a mixed population and also for quality control since the toxic components of J. curcas has deleterious effect on animals. In the present study, the efforts were made to generate the specific SCAR marker for toxic and/or non-toxic J. curcas from RAPD markers. Among the markers specific for toxic and non-toxic varieties, four were selected, purified, cloned, sequenced, and designed primers out of which one set of primers NT-JC/SCAR I/OPQ15-F and R could able to discriminate the non-toxic with toxic Jatropha by giving expected 430 bp size amplification in non-toxic variety. Furthermore, novel multiplex PCR was designed using the nrDNA ITS primers to overcome the false negatives. Present work also demonstrates utility of the conserved regions of nrDNA coding genes in ruling out the artifacts in PCR-like false negatives frequently occur in SCAR due to various reasons. The specific SCAR markers generated in the present investigation will help to distinguish non-toxic from toxic varieties of J. curcas or vice versa, and isolated marker along with designed multiplex protocol has applications in quality control for selective cultivation of non-toxic variety and will also assist in breeding and molecular mapping studies. © 2011 Springer Science+Business Media, LLC.

  10. Transition to non-toxic gunshot use in Olympic shooting: policy implications for IOC and UNEP in resolving an environmental problem.

    Science.gov (United States)

    Thomas, Vernon George; Guitart, Raimon

    2013-10-01

    Olympic shooters discharge, annually, thousands of tons of lead shot which pose toxic risks to animals and may pollute both surface and ground waters. Non-toxic steel shot is an acceptable and effective substitute, but International Shooting Sports Federation (ISSF) rules prevent its adoption. The present policy and rules of the ISSF on lead shot use contravene the International Olympic Committee (IOC) Charter position on environmental protection. The United Nations Environment Programme (UNEP), a formal Olympic partner on environmental protection, has no stated policy on contamination from lead ammunition, despite having declared lead a Priority Area for remedial action, and is pressing to remove lead from the global human environment. The IOC Sport and Environment Commission and UNEP could examine the continued use of lead shot ammunition and advise the IOC Executive Board on appropriate changes in policy and rules that could halt the massive lead shot contamination of shooting range environments world-wide.

  11. Keampferol-3-O-rhamnoside abrogates amyloid beta toxicity by modulating monomers and remodeling oligomers and fibrils to non-toxic aggregates

    Directory of Open Access Journals (Sweden)

    Sharoar Md

    2012-12-01

    Full Text Available Abstract Background Aggregation of soluble, monomeric β- amyloid (Aβ to oligomeric and then insoluble fibrillar Aβ is a key pathogenic feature in development of Alzheimer’s disease (AD. Increasing evidence suggests that toxicity is linked to diffusible Aβ oligomers, rather than to insoluble fibrils. The use of naturally occurring small molecules for inhibition of Aβ aggregation has recently attracted significant interest for development of effective therapeutic strategies against the disease. A natural polyphenolic flavone, Kaempferol-3-O-rhamnoside (K-3-rh, was utilized to investigate its effects on aggregation and cytotoxic effects of Aβ42 peptide. Several biochemical techniques were used to determine the conformational changes and cytotoxic effect of the peptide in the presence and absence of K-3-rh. Results K-3-rh showed a dose-dependent effect against Aβ42 mediated cytotoxicity. Anti-amyloidogenic properties of K-3-rh were found to be efficient in inhibiting fibrilogenesis and secondary structural transformation of the peptide. The consequence of these inhibitions was the accumulation of oligomeric structural species. The accumulated aggregates were smaller, soluble, non-β-sheet and non-toxic aggregates, compared to preformed toxic Aβ oligomers. K-3-rh was also found to have the remodeling properties of preformed soluble oligomers and fibrils. Both of these conformers were found to remodel into non-toxic aggregates. The results showed that K-3-rh interacts with different Aβ conformers, which affects fibril formation, oligomeric maturation and fibrillar stabilization. Conclusion K-3-rh is an efficient molecule to hinder the self assembly and to abrogate the cytotoxic effects of Aβ42 peptide. Hence, K-3-rh and small molecules with similar structure might be considered for therapeutic development against AD.

  12. The potentiation effect makes the difference: Non-toxic concentrations of ZnO nanoparticles enhance Cu nanoparticle toxicity in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Li, Lingxiangyu [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Fernández-Cruz, María Luisa; Connolly, Mona [Departamento de Medio Ambiente, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Madrid 28040 (Spain); Conde, Estefanía; Fernández, Marta [Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid 28040 (Spain); Schuster, Michael [Department of Chemistry, Technische Universität München, Garching 85747 (Germany); Navas, José María, E-mail: jmnavas@inia.es [Departamento de Medio Ambiente, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Madrid 28040 (Spain)

    2015-02-01

    Here we examined whether the addition of a non-toxic concentration (6.25 μg/mL) of zinc oxide nanoparticles (ZnONPs: 19, 35 and 57 nm, respectively) modulates the cytotoxicity of copper nanoparticles (CuNPs, 63 nm in size) in the human hepatoma cell line HepG2. The cytotoxic effect of CuNPs on HepG2 cells was markedly enhanced by the ZnONPs, the largest ZnONPs causing the highest increase in toxicity. However, CuNPs cytotoxicity was not affected by co-incubation with medium containing only zinc ions, indicating the increase in toxicity might be attributed to the particle form of ZnONPs. Transmission electron microscopy (TEM) revealed the presence of CuNPs and ZnONPs inside the cells co-exposed to both types of NP and outflow of cytoplasm through the damaged cell membrane. Inductively coupled plasma mass spectrometry (ICP-MS) determined an increase in the concentration of zinc and a decrease in that of copper in co-exposed cells. On the basis of these results, we propose that accumulation of large numbers of ZnONPs in the cells alters cellular membranes and the cytotoxicity of CuNPs is increased. - Highlights: • ZnONPs at non-toxic concentrations increased the toxicity of CuNPs in vitro. • ZnONPs of larger size provoked a stronger synergistic effect with CuNPs. • The synergistic effect was attributed to the particle fraction of ZnONPs.

  13. Induction and transfer of resistance to poisoning by Amorimia pubiflora in sheep whith non-toxic dosis of the plant and ruminal content

    Directory of Open Access Journals (Sweden)

    Marciel Becker

    2016-04-01

    Full Text Available ABSTRACT: Amorimiapubiflora (Malpighiaceae, which contains sodium monofluoroacetate (MFA is the main cause of "sudden death" in cattle in the Brazilian state of Mato Grosso. This research investigated the induction of resistance to the poisoning in sheep by the continuous administration of non-toxic doses of the plant and also the possibility to transfer this resistance to other sheep by the transfaunation of ruminal fluid. For this a group of four sheep (G1 received daily doses of 0.5g kg-1 for 20 days and after an interval of 15 days were challenged with three daily doses of 1g kg-1 for 3 days. Also the transfer of resistance to A. pubiflora poisoning was evaluated by transfaunation of rumen fluid (100ml for 10 days from G1 sheep to five sheep (G2, followed by challenge with the dose of 1g kg-1 for 3 days (G2D2 and after a three-day interval they received a single dose of 3g kg-1 (G2D3. The degree of resistance was evaluated by monitoring the onset of clinical signs, heart rate, and outcome of the poisoning compared with the control groups, which were challenged with three daily doses of 1g kg1 (G3 and with a single dose of 3g kg-1 (G4. Clinical parameters evaluated in Groups G1 and G2 were significantly less pronounced than those observed in G3 and G4 (control (P<0.05. Sheep in G4 (control died after receiving a single dose of 3g kg-1, while those in G2 (transfaunated survived. These findings demonstrated that consumption of non-toxic doses of A. pubiflora induced resistance in sheep and that this resistance can be transferred by transfaunation. New experiments are needed to determine the most efficient ways to induce resistance and to use this technique in the field to prevent the poisoning.

  14. Potent antifouling compounds produced by marine Streptomyces

    KAUST Repository

    Xu, Ying

    2010-02-01

    Biofouling causes huge economic loss and a recent global ban on organotin compounds as antifouling agents has increased the need for safe and effective antifouling compounds. Five structurally similar compounds were isolated from the crude extract of a marine Streptomyces strain obtained from deep-sea sediments. Antifouling activities of these five compounds and four other structurally-related compounds isolated from a North Sea Streptomyces strain against major fouling organisms were compared to probe structure-activity relationships of compounds. The functional moiety responsible for antifouling activity lies in the 2-furanone ring and that the lipophilicity of compounds substantially affects their antifouling activities. Based on these findings, a compound with a straight alkyl side-chain was synthesized and proved itself as a very effective non-toxic, anti-larval settlement agent against three major fouling organisms. The strong antifouling activity, relatively low toxicity, and simple structures of these compounds make them promising candidates for new antifouling additives. © 2009 Elsevier Ltd. All rights reserved.

  15. Preparation, thermal and flammability properties of a novel form-stable phase change materials based on high density polyethylene/poly(ethylene-co-vinyl acetate)/organophilic montmorillonite nanocomposites/paraffin compounds

    International Nuclear Information System (INIS)

    Cai Yibing; Song Lei; He Qingliang; Yang Dandan; Hu Yuan

    2008-01-01

    The paraffin is one of important thermal energy storage materials with many desirable characteristics (i.e., high heat of fusion, varied phase change temperature, negligible supercooling, self-nucleating, no phase segregation and cheap, etc.), but has low thermal stability and flammable. Hence, a novel form-stable phase change materials (PCM) based on high density polyethylene (HDPE)/poly(ethylene-co-vinyl acetate) (EVA)/organophilic montmorillonite (OMT) nanocomposites and paraffin are prepared by twin-screw extruder technique. The structures of the HDPE-EVA/OMT nanocomposites and the form-stable PCM are evidenced by the X-ray diffraction (XRD), transmission electronic microscopy (TEM) and scanning electronic microscope (SEM). The results of XRD and TEM show that the HDPE-EVA/OMT nanocomposites form the ordered intercalated nanomorphology. The form-stable PCM consists of the paraffin, which acts as a dispersed phase change material and the HDPE-EVA/OMT nanocomposites, which acts as the supporting material. The paraffin disperses in the three-dimensional net structure formed by HDPE-EVA/OMT nanocomposites. The thermal stability, latent heat and flammability properties are characterized by thermogravimetry analysis (TGA), dynamic Fourier-transform infrared (FTIR), differential scanning calorimeter (DSC) and cone calorimeter, respectively. The TGA and dynamic FTIR analyses indicate that the incorporation of suitable amount of OMT into the form-stable PCM increase the thermal stability. The DSC results show that the latent heat of the form-stable PCM has a certain degree decrease. The cone calorimeter shows that the heat release rate (HRR) has remarkably decreases with loading of OMT in the form-stable PCM, contributing to the improved flammability properties

  16. Stable Isotope Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Tissue samples (skin, bone, blood, muscle) are analyzed for stable carbon, stable nitrogen, and stable sulfur analysis. Many samples are used in their entirety for...

  17. New compounds for neutron capture therapy (NCT) and their significance

    International Nuclear Information System (INIS)

    Fairchild, R.G.; Bond, V.P.

    1982-01-01

    Clearly the most effective tumor therapy would be obtained by the selective targeting of cytotoxic agents to tumor cells. Although many biomolecules are known to be taken up in tumors, the targeting of cytotoxic agents to tumors is limited by the fact that other essential cell pools compete with equal or even greater effectiveness. The approach of delivering stable non-toxic isotopes to tumor, with activation by means of an external radiation beam, is advantageous for two reasons: (1) it obviates problems associated with high uptake of isotopes in normal tissues, as these cell pools can be excluded from the radiation field, and (2) the general tumor area can be included in the activating beam field; thus, the possibility exists that all microscopic tumor extensions can be irradiated. As long as range of reaction products is short, dose will be restricted to the tumor, with a resultant high therapeutic ratio. This method can be accomplished with either photon activation therapy (PAT) or Neutron Capture Therapy (NCT), the latter will be emphasized here. The range of the high LET, low OER particles from the 10 B(n,α) 7 Li reaction is approx. 10 μm, or one cell diameter; hence this reaction is optimal for cell killing. A number of biomolecules have been investigated as possible vehicles for transport of boron to tumors, including phenothiazines, thiouracils, porphyrins, nucleosides, and amino acids. Biodistributions of these compounds show selective concentration in tumor adequate for therapy. The biological halflives are in the order of days, allowing the possibility of fractionated or protracted irradiations. The radiobiological and physical implication of these parameters on NCT are discussed. The possibility of using an approximately-monoenergetic, scandium-filtered beam of about 2 keV, to reduce the dose from background radiations by about 85%, is also discussed

  18. Structure of acid-stable carmine.

    Science.gov (United States)

    Sugimoto, Naoki; Kawasaki, Yoko; Sato, Kyoko; Aoki, Hiromitsu; Ichi, Takahito; Koda, Takatoshi; Yamazaki, Takeshi; Maitani, Tamio

    2002-02-01

    Acid-stable carmine has recently been distributed in the U.S. market because of its good acid stability, but it is not permitted in Japan. We analyzed and determined the structure of the major pigment in acid-stable carmine, in order to establish an analytical method for it. Carminic acid was transformed into a different type of pigment, named acid-stable carmine, through amination when heated in ammonia solution. The features of the structure were clarified using a model compound, purpurin, in which the orientation of hydroxyl groups on the A ring of the anthraquinone skeleton is the same as that of carminic acid. By spectroscopic means and the synthesis of acid-stable carmine and purpurin derivatives, the structure of the major pigment in acid-stable carmine was established as 4-aminocarminic acid, a novel compound.

  19. Co-occurrence of non-toxic (cyanopeptolin) and toxic (microcystin) peptides in a bloom of Microcystis sp. from a Chilean lake.

    Science.gov (United States)

    Neumann, U; Campos, V; Cantarero, S; Urrutia, H; Heinze, R; Weckesser, J; Erhard, M

    2000-06-01

    A cyanobacterial bloom occurring in 1998 in lake Tres Pascualas (Concepción/Chile) was found to be dominated by Microcystis sp. The bloom contained both non-toxic (cyanopeptolin-type) and hepatotoxic (microcystin-type) peptides. Cyanopeptolin structure of the non-toxic peptides (called cyanopeptolin VW-1 and VW-2, respectively) was revealed by matrix assisted laser desorption ionization mass spectrometry (MALDI-TOF-MS) of whole cells, showing dominant molecular ions at m/z = 975 and m/z 995, respectively. On post source decay (PSD), both cyanopeptolins showed fragments deriving from Ahp-Phe-MTyr (3-amino-6-hydroxy-2-piperidone), the characteristic partial structure of cyanopeptolins. The amounts of each of the two cyanopeptolins could only roughly be estimated to be >0.1% of bloom material dry weight. In addition the blooms contained microcystins (20 microg/g bloom dry weight as determined by RP-HPLC, 13 microg/g according to ELISA determination). MALDI-TOF-MS revealed several structural variants of microcystin: MCYST-RR (microcystin with Arg and Arg, indicated by m/z 1,038 and confirmed by PSD revealing a m/z = 135 fragment deriving from the Adda side chain, MCYST-FR (microcystin with Phe and Arg, indicated by m/z = 1,015). The presence of [Asp(3)]-MCYST-LR (microcystin with Leu and Arg, Asp non-methylated, indicated by m/z 981), and [Asp(3)]-MCYST-YR (microcystin with Tyr and Arg, Asp non-methylated, indicated by m/z 1,031) were likely. The relative amounts of the peptides varied between February, April, and May. Whole cell extracts from the bloom material revealed specific enzyme inhibitory activities. The serin-proteases trypsin, plasmin, elastase were inhibited, assumable due to the cyanopeptolins found. Elastase and the cysteine-protease papain were not inhibited, inhibitions of protein kinase and glutathione S-transferase (GST) were low. Strong inhibition was observed with protein-phosphatase-1, likely due to the microcystins present in the samples.

  20. Superconductivity at 108 K in the simplest non-toxic double-layer cuprate of Ba2CaCu2O4(O,F)2

    International Nuclear Information System (INIS)

    Shirage, P M; Shivagan, D D; Crisan, A; Tanaka, Y; Kodama, Y; Kito, H; Iyo, A

    2008-01-01

    We report the superconductivity in apical fluorine system of Ba 2 CaCu 2 O 6-y F y : the second member of Ba 2 Ca n-1 Cu n O 2n (O,F) 2 homologous series. The polycrystalline samples of Ba 2 CaCu 2 O 6-y F y (F-0212) were synthesized under high pressure as a parameter of nominal fluorine content (y). Samples with y = 2.0 ∼ 1.2 elucidating the very sharp superconducting transitions in temperature dependence of susceptibility from under doping state to slightly over doping state via optimal doping state. A remarkable highest T c of 108 K has been achieved for the sample synthesized from a nominal composition of Ba 2 CaCu 2 O 4.4 F 1.6 . This T c is highest among the double CuO 2 layered system except for that including toxic elements such as Hg and T1. The T c has been systematically controlled from 57 K to 108 K by controlling the doping state, by designing the starting composition of fluorine and oxygen. The strong dependence of the 'a' and 'c' lattice constants were found on the nominal F content. We propose the Ba 2 CaCu 2 O 4 (O,F) 2 as a promising material for practical use due to its high T c and non-toxicity with a simple crystal structure

  1. Synthesis of Poly(N-vinyl-2-pyrrolidone-co-methyl methacrylate by Maghnite-H+ a Non-toxic Catalyst

    Directory of Open Access Journals (Sweden)

    Mohamed Benadda

    2014-10-01

    Full Text Available In the present work poly (N-vinyl-2-pyrrolidone-co-methyl methacrylate copolymers were prepared successfully and cleanly by a one step process via cationic copolymerization of N-vinyl-2-pyrrolidone (NVP with methyl methacrylate (MMA, in heterogeneous phase using “Maghnite-H+” (Mag-H+ as catalyst in bulk, Maghnite is a montmorillonite sheet silicate clay exchanged with protons to produce Maghnite-H+. Temperature is varied between 20 and 80 °C. The effects of reaction temperature, amount of Mag-H+ on the yield and the intrinsic viscosity (η were investigated. A typical reaction product of poly (NVP-co- MMA was analyzed by infra red spectroscopy (FTIR and 1H-NMR, 13C-NMR spectroscopy as well as by viscosimetry. © 2014 BCREC UNDIP. All rights reservedReceived: 24th November 2013; Revised: 30th June 2014; Accepted: 8th July 2014How to Cite: Benadda, M., Ferrahi, M.I., Belbachir, M. (2014. Synthesis of Poly(N-vinyl-2-pyrrolidone-co-methyl methacrylate by Maghnite-H+ a Non-toxic Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 9 (3: 201-206. (doi: 10.9767/bcrec.9.3.5743.201-206Permalink/DOI: http://dx.doi.org/10.9767/bcrec.9.3.5743.201-206

  2. Inorganic carbon acquisition in potentially toxic and non-toxic diatoms: the effect of pH-induced changes in the seawater carbonate chemistry

    DEFF Research Database (Denmark)

    Trimborn, S; Lundholm, Nina; Thoms, S

    2008-01-01

    . In terms of carbon source, all species took up both CO2 and HCO3-. K-1/2 values for inorganic carbon uptake decreased with increasing pH in two species, while in N. navis-varingica apparent affinities did not change. While the contribution of HCO3- to net fixation was more than 85% in S. stellaris......The effects of pH-induced changes in seawater carbonate chemistry on inorganic carbon (C-i) acquisition and domoic acid (DA) production were studied in two potentially toxic diatom species, Pseudo-nitzschia multiseries and Nitzschia navis-varingica, and the non-toxic Stellarima stellaris. In vivo...... activities of carbonic anhydrase (CA), photosynthetic O-2 evolution and CO2 and HCO3- uptake rates were measured by membrane inlet MS in cells acclimated to low (7.9) and high pH (8.4 or 8.9). Species-specific differences in the mode of carbon acquisition were found. While extracellular carbonic anhydrase (e...

  3. Stable convergence and stable limit theorems

    CERN Document Server

    Häusler, Erich

    2015-01-01

    The authors present a concise but complete exposition of the mathematical theory of stable convergence and give various applications in different areas of probability theory and mathematical statistics to illustrate the usefulness of this concept. Stable convergence holds in many limit theorems of probability theory and statistics – such as the classical central limit theorem – which are usually formulated in terms of convergence in distribution. Originated by Alfred Rényi, the notion of stable convergence is stronger than the classical weak convergence of probability measures. A variety of methods is described which can be used to establish this stronger stable convergence in many limit theorems which were originally formulated only in terms of weak convergence. Naturally, these stronger limit theorems have new and stronger consequences which should not be missed by neglecting the notion of stable convergence. The presentation will be accessible to researchers and advanced students at the master's level...

  4. Nature and sources of suspended particulate organic matter in a tropical estuary during the monsoon and pre-monsoon: Insights from stable isotopes (delta 13C POC, delta 15 N TPN) and carbohydrate signature compounds

    Digital Repository Service at National Institute of Oceanography (India)

    Khodse, V.B.; Bhosle, N.B.

    zooplankton, and then known aliquots (0.25 to 1.5 L) were filtered through pre-combusted (450 °C, 4h) 47 mm GF/F filter papers (0.7 µm, Whatman) for the measurements of suspended particulate matter (SPM), particulate organic carbon (POC), δ13CPOC, δ15NTPN... analysis. 2.3. Determination of bulk parameters and stable isotopes GF/F (0.7 µm, 47 mm) filter containing particulate matter was washed with UV-Milli-Q- water to remove salt and the filter was dried at 40 °C for 24 h. Filter was cooled and weighed...

  5. Radiolysis of other organic compounds

    International Nuclear Information System (INIS)

    Pikaev, A.K.

    1986-01-01

    Peculiarities of radiolysis of organic halogen, phosphorus, sulfur and nitrogen (including amines, amides, nitriles et al.) compounds in liquid phase are discussed. Intermediate and stable finish products of radiolysis of the given compounds, properties and radiochemical yields of these products are considered

  6. Optimization of on-line hydrogen stable isotope ratio measurements of halogen- and sulfur-bearing organic compounds using elemental analyzer–chromium/high-temperature conversion isotope ratio mass spectrometry (EA-Cr/HTC-IRMS)

    Science.gov (United States)

    Gehre, Matthias; Renpenning, Julian; Geilmann, Heike; Qi, Haiping; Coplen, Tyler B.; Kümmel, Steffen; Ivdra, Natalija; Brand, Willi A.; Schimmelmann, Arndt

    2017-01-01

    Rationale: Accurate hydrogen isotopic analysis of halogen- and sulfur-bearing organics has not been possible with traditional high-temperature conversion (HTC) because the formation of hydrogen-bearing reaction products other than molecular hydrogen (H2) is responsible for non-quantitative H2 yields and possible hydrogen isotopic fractionation. Our previously introduced, new chromium-based EA-Cr/HTC-IRMS (Elemental Analyzer–Chromium/High-Temperature Conversion Isotope Ratio Mass Spectrometry) technique focused primarily on nitrogen-bearing compounds. Several technical and analytical issues concerning halogen- and sulfur-bearing samples, however, remained unresolved and required further refinement of the reactor systems.

  7. stableGP

    Data.gov (United States)

    National Aeronautics and Space Administration — The code in the stableGP package implements Gaussian process calculations using efficient and numerically stable algorithms. Description of the algorithms is in the...

  8. Angina Pectoris (Stable Angina)

    Science.gov (United States)

    ... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More Angina Pectoris (Stable Angina) Updated:Aug 21,2017 You may have heard the term “angina pectoris” or “stable angina” in your doctor’s office, ...

  9. Altered deoxyribonuclease activity in cancer cells and its role in non toxic adjuvant cancer therapy with mixed vitamins C and K3.

    Science.gov (United States)

    Taper, Henryk S

    2008-01-01

    The alterations of deoxyribonuclease DNase activity in cancer cells were the basis of the utilization of mixed vitamins C and K3 in a nontoxic, adjuvant cancer therapy. In order to localize exactly the altered activities of DNase in cancer cells, histochemical methods were utilized. The deficiency of alkaline and acid DNase activity appeared to be characteristic for non-necrotic cells of malignant human and animal tumors. This enzymatic deficiency appeared in experimental carcinogenesis before the phenotypic signs of malignancy. Tumor promoters directly reduced the activity of both DNases. The incidence of spontaneous malignant human and animal tumors appeared to be inversely proportional to the intensity of the activity of both DNases in normal cells and tissues from which these tumors were derived. The fact that alkaline and acid DNase activity was reactivated during the spontaneous and therapeutically induced necrosis of cancer cells suggests that this enzymatic deficiency of DNase activity in cancer cells was due to the action of specific inhibitors of DNases. Characteristic variations of serum alkaline DNase activity in positive responders to therapy, examined in more than 800 cancer-bearing patients, may be the basis for the development of a useful test for therapeutic prognosis and for monitoring of cancer bearing patients. Acid DNase was selectively reactivated in malignant tumor cells by vitamin C (sodium ascorbate), whereas alkaline DNase was reactivated by vitamin K3. Joint vitamin C and K3 administration produced in vitro and in vivo tumor growth inhibition, potentiation and sensitization of chemo- and/or radiotherapy and a decrease in the number of metastases in animals with experimental tumors. Joint vitamin C and K3 administration may be considered as a possible new, non-toxic, adjuvant cancer therapy, which can be easily introduced into the classic protocols of clinical cancer therapy without any supplementary risk for patients.

  10. Radioiodine therapy in non-toxic multinodular goitre. The possibility of effect-amplification with recombinant human TSH (rhTSH)

    Energy Technology Data Exchange (ETDEWEB)

    Bonnema, Steen J.; Nielsen, Viveque E.; Hegedues, Laszlo [Odense Univ. Hospital (Denmark). Dept. of Endocrinology and Metabolism

    2006-12-15

    There is no consensus regarding the optimum treatment of benign non-toxic goitre. L-thyroxine suppressive therapy is widely used, but there is poor evidence of its efficacy, and it may have serious adverse effects on health. Surgery is first choice in large goitres or if malignancy is suspected. {sup 131}I therapy results in a one-year goitre reduction of around 40% in multinodular goitres, usually with a high degree of patient satisfaction and improvement of the inspiratory capacity. The effect is attenuated with increasing goitre size. The risk of hypothyroidism is 22-58% within 5-8 years. A sufficient thyroid {sup 131}I uptake is mandatory for {sup 131}I therapy to be feasible and pre-stimulation with recombinant human TSH (rhTSH) increases this considerably. This leads to an increased absorbed thyroid dose by approx.75%, mainly in those patients with the lowest thyroid {sup 131}I uptake, and a more homogeneous intrathyroidal isotope distribution. Pre-stimulation with even a small dose of rhTSH seems to allow a reduction of the {sup 131}I activity while still achieving a mean goitre reduction of approximately 40% within a year. A significantly lower extrathyroidal radiation is achieved by this approach. With an unchanged {sup 131}I activity, rhTSH pre-stimulation improves the goitre reduction by 30-50%. However, this is at the expense of a higher rate of hypothyroidism, cervical pain and transient thyrotoxicosis. Of particular concern is the observation made in healthy persons, that rhTSH results in a transient average thyroid volume increase of 35%. A similar goitre swelling may cause problems in susceptible patients during rhTSH-augmented {sup 131}I therapy. Thus, this concept still needs a closer evaluation before routine use.

  11. Optimization of on-line hydrogen stable isotope ratio measurements of halogen- and sulfur-bearing organic compounds using elemental analyzer-chromium/high-temperature conversion isotope ratio mass spectrometry (EA-Cr/HTC-IRMS).

    Science.gov (United States)

    Gehre, Matthias; Renpenning, Julian; Geilmann, Heike; Qi, Haiping; Coplen, Tyler B; Kümmel, Steffen; Ivdra, Natalija; Brand, Willi A; Schimmelmann, Arndt

    2017-03-30

    Accurate hydrogen isotopic analysis of halogen- and sulfur-bearing organics has not been possible with traditional high-temperature conversion (HTC) because the formation of hydrogen-bearing reaction products other than molecular hydrogen (H 2 ) is responsible for non-quantitative H 2 yields and possible hydrogen isotopic fractionation. Our previously introduced, new chromium-based EA-Cr/HTC-IRMS (Elemental Analyzer-Chromium/High-Temperature Conversion Isotope Ratio Mass Spectrometry) technique focused primarily on nitrogen-bearing compounds. Several technical and analytical issues concerning halogen- and sulfur-bearing samples, however, remained unresolved and required further refinement of the reactor systems. The EA-Cr/HTC reactor was substantially modified for the conversion of halogen- and sulfur-bearing samples. The performance of the novel conversion setup for solid and liquid samples was monitored and optimized using a simultaneously operating dual-detection system of IRMS and ion trap MS. The method with several variants in the reactor, including the addition of manganese metal chips, was evaluated in three laboratories using EA-Cr/HTC-IRMS (on-line method) and compared with traditional uranium-reduction-based conversion combined with manual dual-inlet IRMS analysis (off-line method) in one laboratory. The modified EA-Cr/HTC reactor setup showed an overall H 2 -recovery of more than 96% for all halogen- and sulfur-bearing organic compounds. All results were successfully normalized via two-point calibration with VSMOW-SLAP reference waters. Precise and accurate hydrogen isotopic analysis was achieved for a variety of organics containing F-, Cl-, Br-, I-, and S-bearing heteroelements. The robust nature of the on-line EA-Cr/HTC technique was demonstrated by a series of 196 consecutive measurements with a single reactor filling. The optimized EA-Cr/HTC reactor design can be implemented in existing analytical equipment using commercially available material and

  12. Stable isotopes - separation and application

    International Nuclear Information System (INIS)

    Lockhart, I.M.

    1980-01-01

    In this review, methods used for the separation of stable isotopes ( 12 C, 13 C, 14 N, 15 N, 16 O, 17 O, 18 O, 34 S) will be described. The synthesis of labelled compounds, techniques for detection and assay, and areas of application will also be discussed. Particular attention will be paid to the isotopes of carbon, nitrogen, and oxygen; to date, sulphur isotopes have only assumed a minor role. The field of deuterium chemistry is too extensive for adequate treatment; it will therefore be essentially excluded. (author)

  13. Studies about interaction of hydrogen isotopes with metals and intermetallic compounds

    International Nuclear Information System (INIS)

    Vasut, F.; Anisoara, P.; Zamfirache, M.

    2003-01-01

    Hydrogen is a non-toxic but highly inflammable gas. Compared to other inflammable gases, its range of inflammability in air is much broader (4-74.5%) but it also vaporizes much more easily. Handling of hydrogen in form of hydrides enhances safety. The interaction of hydrogen with metals and intermetallic compounds is a major field within physical chemistry. Using hydride-forming metals and intermetallic compounds, for example, recovery, purification and storage of heavy isotopes in tritium containing system can solve many problems arising in the nuclear-fuel cycle. The paper presents the thermodynamics and the kinetics between hydrogen and metal or intermetallic compounds. (author)

  14. Development and validation of an universal interface for compound-specific stable isotope analysis of chlorine (37Cl/35Cl) by GC-high-temperature conversion (HTC)-MS/IRMS.

    Science.gov (United States)

    Renpenning, Julian; Hitzfeld, Kristina L; Gilevska, Tetyana; Nijenhuis, Ivonne; Gehre, Matthias; Richnow, Hans-Hermann

    2015-03-03

    A universal application of compound-specific isotope analysis of chlorine was thus far limited by the availability of suitable analysis techniques. In this study, gas chromatography in combination with a high-temperature conversion interface (GC-HTC), converting organic chlorine in the presence of H2 to gaseous HCl, was coupled to a dual-detection system, combining an ion trap mass spectrometer (MS) and isotope-ratio mass spectrometer (IRMS). The combination of the MS/IRMS detection enabled a detailed characterization, optimization, and online monitoring of the high-temperature conversion process via ion trap MS as well as a simultaneous chlorine isotope analysis by the IRMS. Using GC-HTC-MS/IRMS, chlorine isotope analysis at optimized conversion conditions resulted in very accurate isotope values (δ(37)Cl(SMOC)) for measured reference material with known isotope composition, including chlorinated ethylene, chloromethane, hexachlorocyclohexane, and trichloroacetic acids methyl ester. Respective detection limits were determined to be <15 nmol Cl on column with achieved precision of <0.3‰.

  15. Electron beam treatment of toxic volatile organic compounds and dioxins

    International Nuclear Information System (INIS)

    Kojima, Takuji

    2006-01-01

    Considerations of wastes based on the reduction, reuse and recycle in daily life are primary measures to conserve our environment, but the control technology is necessary to support these measures. The electron beam (EB) process is promising as an advanced purification process having advantages such as a quick treatment of big volume gas, applicability even for very low concentration pollutants as the further purification at the downstream of existing process, and decomposition of pollutants into non-toxic substances by one process. The EB technology has been developed for treatment of toxic volatile organic compounds (VOCs) in ventilation gas and dioxins in solid waste incineration flue gas. (author)

  16. Stable Boundary Layer Issues

    OpenAIRE

    Steeneveld, G.J.

    2012-01-01

    Understanding and prediction of the stable atmospheric boundary layer is a challenging task. Many physical processes are relevant in the stable boundary layer, i.e. turbulence, radiation, land surface coupling, orographic turbulent and gravity wave drag, and land surface heterogeneity. The development of robust stable boundary layer parameterizations for use in NWP and climate models is hampered by the multiplicity of processes and their unknown interactions. As a result, these models suffer ...

  17. Evolutionary Stable Strategy

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 21; Issue 9. Evolutionary Stable Strategy: Application of Nash Equilibrium in Biology. General Article Volume 21 Issue 9 September 2016 pp 803- ... Keywords. Evolutionary game theory, evolutionary stable state, conflict, cooperation, biological games.

  18. Stable Boundary Layer Issues

    NARCIS (Netherlands)

    Steeneveld, G.J.

    2012-01-01

    Understanding and prediction of the stable atmospheric boundary layer is a challenging task. Many physical processes are relevant in the stable boundary layer, i.e. turbulence, radiation, land surface coupling, orographic turbulent and gravity wave drag, and land surface heterogeneity. The

  19. Normal modified stable processes

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole Eiler; Shephard, N.

    2002-01-01

    Gaussian (NGIG) laws. The wider framework thus established provides, in particular, for added flexibility in the modelling of the dynamics of financial time series, of importance especially as regards OU based stochastic volatility models for equities. In the special case of the tempered stable OU process......This paper discusses two classes of distributions, and stochastic processes derived from them: modified stable (MS) laws and normal modified stable (NMS) laws. This extends corresponding results for the generalised inverse Gaussian (GIG) and generalised hyperbolic (GH) or normal generalised inverse...

  20. Applications of stable isotopes

    International Nuclear Information System (INIS)

    Letolle, R.; Mariotti, A.; Bariac, T.

    1991-06-01

    This report reviews the historical background and the properties of stable isotopes, the methods used for their measurement (mass spectrometry and others), the present technics for isotope enrichment and separation, and at last the various present and foreseeable application (in nuclear energy, physical and chemical research, materials industry and research; tracing in industrial, medical and agronomical tests; the use of natural isotope variations for environmental studies, agronomy, natural resources appraising: water, minerals, energy). Some new possibilities in the use of stable isotope are offered. A last chapter gives the present state and forecast development of stable isotope uses in France and Europe

  1. Analysing Stable Time Series

    National Research Council Canada - National Science Library

    Adler, Robert

    1997-01-01

    We describe how to take a stable, ARMA, time series through the various stages of model identification, parameter estimation, and diagnostic checking, and accompany the discussion with a goodly number...

  2. Amberlyst-15: An Efficient and reusable heterogeneous catalyst for the synthesis of β-amino carbonyl compounds

    Directory of Open Access Journals (Sweden)

    Pathakota Venkata Ramana

    2015-12-01

    Full Text Available A simple and efficient method has been developed for the synthesis of β-amino carbonyl compounds from aromatic ketones, aldehydes and amines by Mannich reaction in the presence of amberlyst-15 as a reusable heterogeneous catalyst at room temperature under solvent-free conditions. The noteworthy advantages of the present method are short reaction times, good product yields, simple procedures and use of non-toxic catalyst.

  3. Activation of р-450-depended monooxygenases changing immunotoxicity of phosphoroorganic compounds due to their metabolism character

    Directory of Open Access Journals (Sweden)

    P.F. Zabrodsky

    2010-03-01

    Full Text Available It was established that the application of the monooxygenase system inductors (MSI of phenobarbital and benzonal up to acute poisoning of animals by trichlorfom in a dose of 1,0 LD50, metabolized in the organism till production of compounds with higher toxicity caused its immunotoxic properties increase. The experiment was carried out on outbred white rats. the acute dimethyldichlorvinylphosphate (1,0 LD50 poisoning, biotransformation of which proceeded with formation of less-toxic and non-toxic compounds after MSI introduction, caused its decrease of suppression influence on immunity system indices

  4. Mini-review: Molecular mechanisms of antifouling compounds

    KAUST Repository

    Qian, Pei-Yuan

    2013-04-01

    Various antifouling (AF) coatings have been developed to protect submerged surfaces by deterring the settlement of the colonizing stages of fouling organisms. A review of the literature shows that effective AF compounds with specific targets are ones often considered non-toxic. Such compounds act variously on ion channels, quorum sensing systems, neurotransmitters, production/release of adhesive, and specific enzymes that regulate energy production or primary metabolism. In contrast, AF compounds with general targets may or may not act through toxic mechanisms. These compounds affect a variety of biological activities including algal photosynthesis, energy production, stress responses, genotoxic damage, immunosuppressed protein expression, oxidation, neurotransmission, surface chemistry, the formation of biofilms, and adhesive production/release. Among all the targets, adhesive production/release is the most common, possibly due to a more extensive research effort in this area. Overall, the specific molecular targets and the molecular mechanisms of most AF compounds have not been identified. Thus, the information available is insufficient to draw firm conclusions about the types of molecular targets to be used as sensitive biomarkers for future design and screening of compounds with AF potential. In this review, the relevant advantages and disadvantages of the molecular tools available for studying the molecular targets of AF compounds are highlighted briefly and the molecular mechanisms of the AF compounds, which are largely a source of speculation in the literature, are discussed. © 2013 Copyright Taylor and Francis Group, LLC.

  5. Quantitative imaging of subcellular metabolism with stable isotopes and multi-isotope imaging mass spectrometry

    Science.gov (United States)

    Steinhauser, Matthew L.; Lechene, Claude P.

    2014-01-01

    Multi-isotope imaging mass spectrometry (MIMS) is the quantitative imaging of stable isotope labels in cells with a new type of secondary ion mass spectrometer (NanoSIMS). The power of the methodology is attributable to (i) the immense advantage of using non-toxic stable isotope labels, (ii) high resolution imaging that approaches the resolution of usual transmission electron microscopy and (iii) the precise quantification of label down to 1 part-per-million and spanning several orders of magnitude. Here we review the basic elements of MIMS and describe new applications of MIMS to the quantitative study of metabolic processes including protein and nucleic acid synthesis in model organisms ranging from microbes to humans. PMID:23660233

  6. Organolanthanoid compounds

    International Nuclear Information System (INIS)

    Schumann, H.

    1984-01-01

    Up to little more than a decade ago organolanthanoid compounds were still a curiosity. Apart from the description of an isolated number of cyclopentadienyl and indenyl derivatives, very few significant contributions had been made to this interesting sector of organometallic chemistry. However, subsequent systematic studies using modern preparative and analytical techniques, together with X-ray single crystal structure determinations, enabled the isolation and characterization of a large number of very interesting homoleptic and heteroleptic compounds in which the lanthanoid is bound to hydrogen, to substituted or unsubstituted cyclopentadienyl groups, to allyl or alkynyl groups, or even to phosphorus ylides, trimethylsilyl, and carbonylmetal groups. These compounds, which are all extremely sensitive to oxygen and water, open up new possibilities in the field of catalysis and have great potential in organic synthesis - as recent studies with pentamethylcyclopentadienyl derivatives, organolanthanoid(II) compounds, and hexamethyllanthanoid complexes have already shown. (orig.) [de

  7. Calcium stable isotope geochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Gausonne, Nikolaus [Muenster Univ. (Germany). Inst. fuer Mineralogie; Schmitt, Anne-Desiree [Strasbourg Univ. (France). LHyGeS/EOST; Heuser, Alexander [Bonn Univ. (Germany). Steinmann-Inst. fuer Geologie, Mineralogie und Palaeontologie; Wombacher, Frank [Koeln Univ. (Germany). Inst. fuer Geologie und Mineralogie; Dietzel, Martin [Technische Univ. Graz (Austria). Inst. fuer Angewandte Geowissenschaften; Tipper, Edward [Cambridge Univ. (United Kingdom). Dept. of Earth Sciences; Schiller, Martin [Copenhagen Univ. (Denmark). Natural History Museum of Denmark

    2016-08-01

    This book provides an overview of the fundamentals and reference values for Ca stable isotope research, as well as current analytical methodologies including detailed instructions for sample preparation and isotope analysis. As such, it introduces readers to the different fields of application, including low-temperature mineral precipitation and biomineralisation, Earth surface processes and global cycling, high-temperature processes and cosmochemistry, and lastly human studies and biomedical applications. The current state of the art in these major areas is discussed, and open questions and possible future directions are identified. In terms of its depth and coverage, the current work extends and complements the previous reviews of Ca stable isotope geochemistry, addressing the needs of graduate students and advanced researchers who want to familiarize themselves with Ca stable isotope research.

  8. Calcium stable isotope geochemistry

    International Nuclear Information System (INIS)

    Gausonne, Nikolaus; Schmitt, Anne-Desiree; Heuser, Alexander; Wombacher, Frank; Dietzel, Martin; Tipper, Edward; Schiller, Martin

    2016-01-01

    This book provides an overview of the fundamentals and reference values for Ca stable isotope research, as well as current analytical methodologies including detailed instructions for sample preparation and isotope analysis. As such, it introduces readers to the different fields of application, including low-temperature mineral precipitation and biomineralisation, Earth surface processes and global cycling, high-temperature processes and cosmochemistry, and lastly human studies and biomedical applications. The current state of the art in these major areas is discussed, and open questions and possible future directions are identified. In terms of its depth and coverage, the current work extends and complements the previous reviews of Ca stable isotope geochemistry, addressing the needs of graduate students and advanced researchers who want to familiarize themselves with Ca stable isotope research.

  9. Labelled compounds. (Pt. B)

    International Nuclear Information System (INIS)

    Buncel, E.; Jones, J.R.

    1991-01-01

    Since the end of World War II there has been a tremendous increase in the number of compounds that have been synthesized with radioactive or stable isotopes. They have found application in many diverse fields, so much so, that hardly a single area in pure and applied science has not benefited. Not surprisingly it has been reflected in appearance of related publications. The early proceedings of the Symposia on Advances in Trace Methodology were soon followed by various Euratom sponsored meetings in which methods of preparing and storing labelled compounds featured prominently. In due course a resurgence of interest in stable isotopes, brought about by their greater availability (also lower cost) and partly by development of new techniques such as gas chromatography - mass spectrometry (gc-ms), led to the publication of proceedings of several successful conferences. More recently conferences dealing with the synthesis and applications of isotopes and isotopically labelled compounds have been established on a regular basis. In addition to the proceedings of conferences and journal publications individuals left their mark by producing definitive texts, usually on specific nuclides. Only the classic two volume publication of Murray and Williams (Organic syntheses with isotopes, New York 1985), now over 30 years old and out of print, attempted to do justice to several nuclides. With the large amount of work that has been undertaken since then it seems unlikely that an updated edition could be produced. The alternative strategy was to ask scientists currently active to review specific areas and this is the approach adopted in the present series of monographs. In this way it is intended to cover the broad advances that have been made in the synthesis and applications of isotopes and isotopically labelled compounds in the physical and biomedical sciences. (author). refs.; figs.; tabs

  10. Sensitivity of salad greens (Lactuca sativa L. and Eruca sativa Mill. exposed to crude extracts of toxic and non-toxic cyanobacteria

    Directory of Open Access Journals (Sweden)

    MC. Bittencourt-Oliveira

    Full Text Available We evaluated the effect of crude extracts of the microcystin-producing (MC+ cyanobacteria Microcystis aeruginosa on seed germination and initial development of lettuce and arugula, at concentrations between 0.5 μg.L–1 and 100 μg.L–1 of MC-LR equivalent, and compared it to crude extracts of the same species without the toxin (MC–. Crude extracts of the cyanobacteria with MC (+ and without MC (– caused different effects on seed germination and initial development of the salad green seedlings, lettuce being more sensitive to both extracts when compared to arugula. Crude extracts of M. aeruginosa (MC+ caused more evident effects on seed germination and initial development of both species of salad greens than MC–. Concentrations of 75 μg.L–1 and 100 μg.L–1 of MC–LR equivalent induced a greater occurrence of abnormal seedlings in lettuce, due to necrosis of the radicle and shortening of this organ in normal seedlings, as well as the reduction in total chlorophyll content and increase in the activity of the antioxidant enzyme peroxidase (POD. The MC– extract caused no harmful effects to seed germination and initial development of seedlings of arugula. However, in lettuce, it caused elevation of POD enzyme activity, decrease in seed germination at concentrations of 75 μg.L–1 (MC-75 and 100 μg.L–1 (MC-100, and shortening of the radicle length, suggesting that other compounds present in the cyanobacteria extracts contributed to this result. Crude extracts of M. aeruginosa (MC– may contain other compounds, besides the cyanotoxins, capable of causing inhibitory or stimulatory effects on seed germination and initial development of salad green seedlings. Arugula was more sensitive to the crude extracts of M. aeruginosa (MC+ and (MC– and to other possible compounds produced by the cyanobacteria.

  11. Toxicology of perfluorinated compounds

    Energy Technology Data Exchange (ETDEWEB)

    Stahl, Thorsten [Hessian State Laboratory, Wiesbaden (Germany); Mattern, Daniela; Brunn, Hubertus [Hessian State Laboratory, Giessen (Germany)

    2011-12-15

    Perfluorinated compounds [PFCs] have found a wide use in industrial products and processes and in a vast array of consumer products. PFCs are molecules made up of carbon chains to which fluorine atoms are bound. Due to the strength of the carbon/fluorine bond, the molecules are chemically very stable and are highly resistant to biological degradation; therefore, they belong to a class of compounds that tend to persist in the environment. These compounds can bioaccumulate and also undergo biomagnification. Within the class of PFC chemicals, perfluorooctanoic acid and perfluorosulphonic acid are generally considered reference substances. Meanwhile, PFCs can be detected almost ubiquitously, e.g., in water, plants, different kinds of foodstuffs, in animals such as fish, birds, in mammals, as well as in human breast milk and blood. PFCs are proposed as a new class of 'persistent organic pollutants'. Numerous publications allude to the negative effects of PFCs on human health. The following review describes both external and internal exposures to PFCs, the toxicokinetics (uptake, distribution, metabolism, excretion), and the toxicodynamics (acute toxicity, subacute and subchronic toxicities, chronic toxicity including carcinogenesis, genotoxicity and epigenetic effects, reproductive and developmental toxicities, neurotoxicity, effects on the endocrine system, immunotoxicity and potential modes of action, combinational effects, and epidemiological studies on perfluorinated compounds). (orig.)

  12. Multipurpose Compound

    Science.gov (United States)

    1983-01-01

    Specially formulated derivatives of an unusual basic compound known as Alcide may be the answer to effective treatment and prevention of the disease bovine mastitis, a bacterial inflammation of a cow's mammary gland that results in loss of milk production and in extreme cases, death. Manufactured by Alcide Corporation the Alcide compound has killed all tested bacteria, virus and fungi, shortly after contact, with minimal toxic effects on humans or animals. Alcide Corporation credits the existence of the mastitis treatment/prevention products to assistance provided the company by NERAC, Inc.

  13. Stable isotope studies

    International Nuclear Information System (INIS)

    Ishida, T.

    1992-01-01

    The research has been in four general areas: (1) correlation of isotope effects with molecular forces and molecular structures, (2) correlation of zero-point energy and its isotope effects with molecular structure and molecular forces, (3) vapor pressure isotope effects, and (4) fractionation of stable isotopes. 73 refs, 38 figs, 29 tabs

  14. Interactive Stable Ray Tracing

    DEFF Research Database (Denmark)

    Dal Corso, Alessandro; Salvi, Marco; Kolb, Craig

    2017-01-01

    Interactive ray tracing applications running on commodity hardware can suffer from objectionable temporal artifacts due to a low sample count. We introduce stable ray tracing, a technique that improves temporal stability without the over-blurring and ghosting artifacts typical of temporal post-pr...

  15. The Stable Concordance Genus

    OpenAIRE

    Kearney, M. Kate

    2013-01-01

    The concordance genus of a knot is the least genus of any knot in its concordance class. Although difficult to compute, it is a useful invariant that highlights the distinction between the three-genus and four-genus. In this paper we define and discuss the stable concordance genus of a knot, which describes the behavior of the concordance genus under connected sum.

  16. Stable radiographic scanning agents

    International Nuclear Information System (INIS)

    1976-01-01

    Stable compositions which are useful in the preparation of Technetium-99m-based scintigraphic agents are discussed. They are comprised of ascorbic acid or a pharmaceutically acceptable salt or ester thereof in combination with a pertechnetate reducing agent or dissolved in oxidized pertechnetate-99m (sup(99m)TcO 4 - ) solution

  17. Some stable hydromagnetic equilibria

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, J L; Oberman, C R; Kulsrud, R M; Frieman, E A [Project Matterhorn, Princeton University, Princeton, NJ (United States)

    1958-07-01

    We have been able to find and investigate the properties of equilibria which are hydromagnetically stable. These equilibria can be obtained, for example, by wrapping conductors helically around the stellarator tube. Systems with I = 3 or 4 are indicated to be optimum for stability purposes. In some cases an admixture of I = 2 fields can be advantageous for achieving equilibrium. (author)

  18. Polymer compound

    NARCIS (Netherlands)

    1995-01-01

    A Polymer compound comprising a polymer (a) that contains cyclic imidesgroups and a polymer (b) that contains monomer groups with a 2,4-diamino-1,3,5-triazine side group. According to the formula (see formula) whereby themole percentage ratio of the cyclic imides groups in the polymer compoundwith

  19. Mesoionic Compounds

    Indian Academy of Sciences (India)

    Organic Chemistry. Kamatak University,. Dharwad. Her research interests are synthesis, reactions and synthetic utility of sydnones. She is currently working on electrochemical and insecticidal/antifungal activities for some of these compounds. Keywords. Aromaticity, mesoionic hetero- cycles, sydnones, tandem re- actions.

  20. Nitrogen compounds behavior under irradiation environment

    International Nuclear Information System (INIS)

    Ichikawa, Nagayoshi; Takagi, Junichi; Yotsuyanagi, Tadasu

    1991-01-01

    Laboratory experiments were performed to evaluate nitrogen compounds behavior in liquid phase under irradiation environments. Nitrogen compounds take a chemical form of ammonium ion under reducing condition by gamma irradiation, whereas ammonium ions are rather stable even under oxidizing conditions. Key reactions were pointed out and their reaction rate constants and activation energies were estimated through computer code simulation. A reaction scheme for nitrogen compounds including protonate reaction was proposed. (author)

  1. Metabolic studies in man using stable isotopes

    International Nuclear Information System (INIS)

    Faust, H.; Jung, K.; Krumbiegel, P.

    1993-01-01

    In this project, stable isotope compounds and stable isotope pharmaceuticals were used (with emphasis on the application of 15 N) to study several aspects of nitrogen metabolism in man. Of the many methods available, the 15 N stable isotope tracer technique holds a special position because the methodology for application and nitrogen isotope analysis is proven and reliable. Valid routine methods using 15 N analysis by emission spectrometry have been demonstrated. Several methods for the preparation of biological material were developed during our participation in the Coordinated Research Programme. In these studies, direct procedures (i.e. use of diluted urine as a samples without chemical preparation) or rapid isolation methods were favoured. Within the scope of the Analytical Quality Control Service (AQCS) enriched stable isotope reference materials for medical and biological studies were prepared and are now available through the International Atomic Energy Agency. The materials are of special importance as the increasing application of stable isotopes as tracers in medical, biological and agricultural studies has focused interest on reliable measurements of biological material of different origin. 24 refs

  2. Experimental investigation of the catalytic decomposition and combustion characteristics of a non-toxic ammonium dinitramide (ADN)-based monopropellant thruster

    Science.gov (United States)

    Chen, Jun; Li, Guoxiu; Zhang, Tao; Wang, Meng; Yu, Yusong

    2016-12-01

    Low toxicity ammonium dinitramide (ADN)-based aerospace propulsion systems currently show promise with regard to applications such as controlling satellite attitude. In the present work, the decomposition and combustion processes of an ADN-based monopropellant thruster were systematically studied, using a thermally stable catalyst to promote the decomposition reaction. The performance of the ADN propulsion system was investigated using a ground test system under vacuum, and the physical properties of the ADN-based propellant were also examined. Using this system, the effects of the preheating temperature and feed pressure on the combustion characteristics and thruster performance during steady state operation were observed. The results indicate that the propellant and catalyst employed during this work, as well as the design and manufacture of the thruster, met performance requirements. Moreover, the 1 N ADN thruster generated a specific impulse of 223 s, demonstrating the efficacy of the new catalyst. The thruster operational parameters (specifically, the preheating temperature and feed pressure) were found to have a significant effect on the decomposition and combustion processes within the thruster, and the performance of the thruster was demonstrated to improve at higher feed pressures and elevated preheating temperatures. A lower temperature of 140 °C was determined to activate the catalytic decomposition and combustion processes more effectively compared with the results obtained using other conditions. The data obtained in this study should be beneficial to future systematic and in-depth investigations of the combustion mechanism and characteristics within an ADN thruster.

  3. Stable isotope analysis

    International Nuclear Information System (INIS)

    Tibari, Elghali; Taous, Fouad; Marah, Hamid

    2014-01-01

    This report presents results related to stable isotopes analysis carried out at the CNESTEN DASTE in Rabat (Morocco), on behalf of Senegal. These analyzes cover 127 samples. These results demonstrate that Oxygen-18 and Deuterium in water analysis were performed by infrared Laser spectroscopy using a LGR / DLT-100 with Autosampler. Also, the results are expressed in δ values (‰) relative to V-SMOW to ± 0.3 ‰ for oxygen-18 and ± 1 ‰ for deuterium.

  4. Forensic Stable Isotope Biogeochemistry

    Science.gov (United States)

    Cerling, Thure E.; Barnette, Janet E.; Bowen, Gabriel J.; Chesson, Lesley A.; Ehleringer, James R.; Remien, Christopher H.; Shea, Patrick; Tipple, Brett J.; West, Jason B.

    2016-06-01

    Stable isotopes are being used for forensic science studies, with applications to both natural and manufactured products. In this review we discuss how scientific evidence can be used in the legal context and where the scientific progress of hypothesis revisions can be in tension with the legal expectations of widely used methods for measurements. Although this review is written in the context of US law, many of the considerations of scientific reproducibility and acceptance of relevant scientific data span other legal systems that might apply different legal principles and therefore reach different conclusions. Stable isotopes are used in legal situations for comparing samples for authenticity or evidentiary considerations, in understanding trade patterns of illegal materials, and in understanding the origins of unknown decedents. Isotope evidence is particularly useful when considered in the broad framework of physiochemical processes and in recognizing regional to global patterns found in many materials, including foods and food products, drugs, and humans. Stable isotopes considered in the larger spatial context add an important dimension to forensic science.

  5. Compound odontoma

    Directory of Open Access Journals (Sweden)

    Monica Yadav

    2012-01-01

    Full Text Available Odontomas have been extensively reported in the dental literature, and the term refers to tumors of odontogenic origin. Though the exact etiology is still unknown, the postulated causes include: local trauma, infection, inheritance and genetic mutation. The majority of the lesions are asymptomatic; however, may be accompanied with pain and swelling as secondary complaints in some cases. Here, we report a case of a compound odontome in a 14 year old patient.

  6. Advanced thermally stable jet fuels

    Energy Technology Data Exchange (ETDEWEB)

    Schobert, H.H.

    1999-01-31

    The Pennsylvania State University program in advanced thermally stable coal-based jet fuels has five broad objectives: (1) Development of mechanisms of degradation and solids formation; (2) Quantitative measurement of growth of sub-micrometer and micrometer-sized particles suspended in fuels during thermal stressing; (3) Characterization of carbonaceous deposits by various instrumental and microscopic methods; (4) Elucidation of the role of additives in retarding the formation of carbonaceous solids; (5) Assessment of the potential of production of high yields of cycloalkanes by direct liquefaction of coal. Future high-Mach aircraft will place severe thermal demands on jet fuels, requiring the development of novel, hybrid fuel mixtures capable of withstanding temperatures in the range of 400--500 C. In the new aircraft, jet fuel will serve as both an energy source and a heat sink for cooling the airframe, engine, and system components. The ultimate development of such advanced fuels requires a thorough understanding of the thermal decomposition behavior of jet fuels under supercritical conditions. Considering that jet fuels consist of hundreds of compounds, this task must begin with a study of the thermal degradation behavior of select model compounds under supercritical conditions. The research performed by The Pennsylvania State University was focused on five major tasks that reflect the objectives stated above: Task 1: Investigation of the Quantitative Degradation of Fuels; Task 2: Investigation of Incipient Deposition; Task 3: Characterization of Solid Gums, Sediments, and Carbonaceous Deposits; Task 4: Coal-Based Fuel Stabilization Studies; and Task 5: Exploratory Studies on the Direct Conversion of Coal to High Quality Jet Fuels. The major findings of each of these tasks are presented in this executive summary. A description of the sub-tasks performed under each of these tasks and the findings of those studies are provided in the remainder of this volume

  7. A multi-step approach for testing non-toxic amphiphilic antifouling coatings against marine microfouling at different levels of biological complexity.

    Science.gov (United States)

    Zecher, Karsten; Aitha, Vishwa Prasad; Heuer, Kirsten; Ahlers, Herbert; Roland, Katrin; Fiedel, Michael; Philipp, Bodo

    2018-03-01

    Marine biofouling on artificial surfaces such as ship hulls or fish farming nets causes enormous economic damage. The time for the developmental process of antifouling coatings can be shortened by reliable laboratory assays. For designing such test systems, it is important that toxic effects can be excluded, that multiple parameters can be addressed simultaneously and that mechanistic aspects can be included. In this study, a multi-step approach for testing antifouling coatings was established employing photoautotrophic biofilm formation of marine microorganisms in micro- and mesoscoms. Degree and pattern of biofilm formation was determined by quantification of chlorophyll fluorescence. For the microcosms, co-cultures of diatoms and a heterotrophic bacterium were exposed to fouling-release coatings. For the mesocosms, a novel device was developed that permits parallel quantification of a multitude of coatings under defined conditions with varying degrees of shear stress. Additionally, the antifouling coatings were tested for leaching of potential compounds and finally tested in sea trials. This multistep-approach revealed that the individual steps led to consistent results regarding antifouling activity of the coatings. Furthermore, the novel mesocosm system can be employed for advanced antifouling analysis including metagenomic approaches for determination of microbial diversity attaching to different coatings under changing shear forces. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Magnesium compounds

    Science.gov (United States)

    Kramer, D.A.

    2007-01-01

    Seawater and natural brines accounted for about 52 percent of U.S. magnesium compounds production in 2006. Dead-burned magnesia was produced by Martin Marietta Magnesia Specialties from well brines in Michigan. Caustic-calcined magnesia was recovered from sea-water by Premier Chemicals in Florida; from well brines in Michigan by Martin Marietta and Rohm and Haas; and from magnesite in Nevada by Premier Chemicals. Intrepid Potash-Wendover and Great Salt Lake Minerals recovered magnesium chloride brines from the Great Salt Lake in Utah. Magnesium hydroxide was produced from brucite by Applied Chemical Magnesias in Texas, from seawater by SPI Pharma in Delaware and Premier Chemicals in Florida, and by Martin Marietta and Rohm and Haas from their operations mentioned above. About 59 percent of the magnesium compounds consumed in the United States was used for refractories that are used mainly to line steelmaking furnaces. The remaining 41 percent was consumed in agricultural, chemical, construction, environmental and industrial applications.

  9. Compound odontoma

    Directory of Open Access Journals (Sweden)

    José Marcelo Vargas Pinto

    2008-01-01

    Full Text Available Odontomas are the most common types of odontogenic tumors, as they are considered more as a developmental anomaly (hamartoma than as a true neoplasia. The aim of the present study is to describe a clinical case of compound odontoma, analyzing its most commonsigns, its region of location, the decade of life and patient’s gender, disorders that may occur as well as the treatment proposed. In order to attain this objective, the method was description of the present clinical case and bibliographic revision, arriving at the result that the treatment for this type of lesion invariably is surgical removal (enucleation and curettage and the prognosis is excellent. The surgical result was followed up in the post-operative period by radiographic exam, and it was possible to conclude that there was complete cicatrization and tissue repair.

  10. Magnesium compounds

    Science.gov (United States)

    Kramer, D.A.

    2012-01-01

    Seawater and natural brines accounted for about 57 percent of magnesium compounds produced in the United States in 2011. Dead-burned magnesia was produced by Martin Marietta Magnesia Specialties LLC from well brines in Michigan. Caustic-calcined magnesia was recovered from seawater by Premier Magnesia LLC in Florida, from well brines in Michigan by Martin Marietta and from magnesite in Nevada by Premier Magnesia. Intrepid Potash Wendover LLC and Great Salt Lake Minerals Corp. recovered magnesium chloride brines from the Great Salt Lake in Utah. Magnesium hydroxide was produced from seawater by SPI Pharma Inc. in Delaware and Premier Magnesia in Florida, and by Martin Marietta from its brine operation in Michigan.

  11. Thermodynamically stable amyloid-β monomers have much lower membrane affinity than the small oligomers

    Directory of Open Access Journals (Sweden)

    Bidyut eSarkar

    2013-04-01

    Full Text Available Amyloid beta (Aβ is an extracellular 39-43 residue long peptide present in the mammalian cerebrospinal fluid, whose aggregation is associated with Alzheimer’s disease. Small oligomers of Aβ are currently thought to be the key to toxicity. However, it is not clear why the monomers of Aβ are non-toxic, and at what stage of aggregation toxicity emerges. Interactions of Aβ with cell membranes is thought to be the initiator of toxicity, but membrane-binding studies with different preparations of monomers and oligomers have not settled this issue. We have earlier found that thermodynamically stable Aβ monomers emerge spontaneously from oligomeric mixtures upon long term incubation in physiological solutions (Nag et al, JBC, 2011. Here we show that the membrane-affinity of these stable Aβ monomers is much lower than that of a mixture of small oligomers (containing dimers to decamers, providing a clue to the emergence of toxicity. Fluorescently labeled Aβ40 monomers show negligible binding to cell membranes of a neuronal cell line (RN46A at physiological concentrations (250 nM, while oligomers at the same concentrations show strong binding within 30 minutes of incubation. The increased affinity most likely does not require any specific neuronal receptor, since this difference in membrane-affinity was also observed in a somatic cell-line (HEK 293T. Similar results are also obtained for Aβ42 monomers and oligomers. Minimal amount of cell death is observed at these concentrations even after 36 hours of incubation. It is likely that membrane binding precedes subsequent slower toxic events induced by Aβ. Our results a provide an explanation for the non-toxic nature of Aβ monomers, b suggest that Aβ toxicity emerges at the initial oligomeric phase, and c provide a quick assay for monitoring the benign-to-toxic transformation of Aβ.

  12. Theory of stable allocations

    Directory of Open Access Journals (Sweden)

    Pantelić Svetlana

    2014-01-01

    Full Text Available The Swedish Royal Academy awarded the 2012 Nobel Prize in Economics to Lloyd Shapley and Alvin Roth, for the theory of stable allocations and the practice of market design. These two American researchers worked independently from each other, combining basic theory and empirical investigations. Through their experiments and practical design they generated a flourishing field of research and improved the performance of many markets. Born in 1923 in Cambridge, Massachusetts, Shapley defended his doctoral thesis at Princeton University in 1953. For many years he worked at RAND, and for more than thirty years he was a professor at UCLA University. He published numerous scientific papers, either by himself or in cooperation with other economists.

  13. Bi-stable optical actuator

    Science.gov (United States)

    Holdener, Fred R.; Boyd, Robert D.

    2000-01-01

    The present invention is a bi-stable optical actuator device that is depowered in both stable positions. A bearing is used to transfer motion and smoothly transition from one state to another. The optical actuator device may be maintained in a stable position either by gravity or a restraining device.

  14. Isotopically modified compounds

    International Nuclear Information System (INIS)

    Kuruc, J.

    2009-01-01

    In this chapter the nomenclature of isotopically modified compounds in Slovak language is described. This chapter consists of following parts: (1) Isotopically substituted compounds; (2) Specifically isotopically labelled compounds; (3) Selectively isotopically labelled compounds; (4) Non-selectively isotopically labelled compounds; (5) Isotopically deficient compounds.

  15. Hydrolytically stable titanium-45

    DEFF Research Database (Denmark)

    Severin, Gregory; Fonslet, Jesper; Zhuravlev, Fedor

    2014-01-01

    metal-based chemotherapeutics such as cisplatin. The aim of our work has been to produce the radioactive analogue of one of these Ti(IV)-salan compounds, Ti-salan-dipic [2], which has hydro-lytic stability on the order of weeks. Not only will this allow us to shed some light on the still un...... the physical characteristics are extremely desirable: 45Ti has a 3 hour half-life, a positron branching ratio of 85 %, a low Eβmax of 1.04 MeV, and negligible secondary gamma emission. In terms of isotope production, 45Ti is transmuted from naturally mono-isotopic 45Sc by low energy proton irradiation...... to a water-cooled silver plate. The activated foil was dissolved in 4M HCl, dried under argon at 120 oC, and taken back up in 12M HCl. Here, four (i-iv below) different approaches to removing the Ti from the Sc and labeling were taken with varying success. Briefly: i. 45Ti was separated on hydroxamate resin...

  16. Relative quantification of PIK3CA gene expression level in fine-needle aspiration biopsy thyroid specimens collected from patients with papillary thyroid carcinoma and non-toxic goitre by real-time RT-PCR

    Directory of Open Access Journals (Sweden)

    Wojciechowska-Durczyńska Katarzyna

    2010-08-01

    Full Text Available Abstract Background Recent studies have shown that the phosphatidylinositol 3-kinase (PI3K signaling pathway is important regulator of many cellular events, including apoptosis, proliferation and motility. PI3K pathway alterations (PIK3CA gene mutations and/or amplification have been observed in various human tumours. In the majority of diagnosed cases, mutations are localized in one of the three "hot spots" in the gene, responsible for coding catalytic subunit α of class I PI3K (PIK3CA. Mutations and amplification of PIK3CA gene are characteristic for thyroid cancer, as well. Methods The aim of our study was to examine a gene expression level of PIK3CA in fine-needle aspiration biopsy (FNAB thyroid specimens in two types of thyroid lesions, papillary thyroid carcinoma (PTC and non-toxic goitre (NTG. Following conventional cytological examination, 42 thyroid FNAB specimens, received from patients with PTC (n = 20 and NTG (n = 22, were quantitatively evaluated regarding PIK3CA expression level by real-time PCR in the ABI PRISM® 7500 Sequence Detection System. Results Significantly higher expression level (RQ of PIK3CA in PTC group has been noted in comparison with NTG group (p Conclusion These observations may suggest role of PIK3CA alterations in PTC carcinogenesis.

  17. One-dimensional stable distributions

    CERN Document Server

    Zolotarev, V M

    1986-01-01

    This is the first book specifically devoted to a systematic exposition of the essential facts known about the properties of stable distributions. In addition to its main focus on the analytic properties of stable laws, the book also includes examples of the occurrence of stable distributions in applied problems and a chapter on the problem of statistical estimation of the parameters determining stable laws. A valuable feature of the book is the author's use of several formally different ways of expressing characteristic functions corresponding to these laws.

  18. Thermodynamic stability studies of Ce-Sb compounds with Fe

    Science.gov (United States)

    Xie, Yi; Zhang, Jinsuo; Benson, Michael T.; Mariani, Robert D.

    2018-02-01

    Lanthanide fission products can migrate to the fuel periphery and react with cladding, causing fuel-cladding chemical interaction (FCCI). Adding a fuel additive dopant, such as Sb, can bind lanthanide, such as Ce, into metallic compounds and thus prevent migration. The present study focuses on the thermodynamic stability of Ce-Sb compounds when in contact with the major cladding constituent Fe by conducting diffusion couple tests. Ce-Sb compounds have shown high thermodynamic stability as they did not react with Fe. When Fe-Sb compounds contacted with Ce, Sb was separated out of Fe-Sb compounds and formed the more stable Ce-Sb compounds.

  19. Mechanisms and Therapeutic Implications of Cell Death Induction by Indole Compounds

    International Nuclear Information System (INIS)

    Ahmad, Aamir; Sakr, Wael A.; Rahman, KM Wahidur

    2011-01-01

    Indole compounds, obtained from cruciferous vegetables, are well-known for their anti-cancer properties. In particular, indole-3-carbinol (I3C) and its dimeric product, 3,3′-diindolylmethane (DIM), have been widely investigated for their effectiveness against a number of human cancers in vitro as well as in vivo. These compounds are effective inducers of apoptosis and the accumulating evidence documenting their ability to modulate multiple cellular signaling pathways is a testimony to their pleiotropic behavior. Here we attempt to update current understanding on the various mechanisms that are responsible for the apoptosis-inducing effects by these compounds. The significance of apoptosis-induction as a desirable attribute of anti-cancer agents such as indole compounds cannot be overstated. However, an equally intriguing property of these compounds is their ability to sensitize cancer cells to standard chemotherapeutic agents. Such chemosensitizing effects of indole compounds can potentially have major clinical implications because these non-toxic compounds can reduce the toxicity and drug-resistance associated with available chemotherapies. Combinational therapy is increasingly being realized to be better than single agent therapy and, through this review article, we aim to provide a rationale behind combination of natural compounds such as indoles with conventional therapeutics

  20. Stable isotope research pool inventory

    International Nuclear Information System (INIS)

    1980-12-01

    This report contains a listing of electromagnetically separated stable isotopes which are available for distribution within the United States for non-destructive research use from the Oak Ridge National Laboratory on a loan basis. This inventory includes all samples of stable isotopes in the Materials Research Collection and does not designate whether a sample is out on loan or in reprocessing

  1. Treatment of solitary, autonomously-functioning, non-toxic thyroid nodules with I131 Adenema tiroideo autónomo no tóxico tratamiento con I131

    Directory of Open Access Journals (Sweden)

    Federico Uribe Londoño

    1991-03-01

    Full Text Available

    Fifteen euthyroid patients (14 women and 1man with solitary autonomously functioning non-toxic thyroid nodules (AFTN were treated with high doses of I131 (mean 19.2 mCi. Diagnosis was made by I131 thyroid scan and triiodothyronine suppression test. The size of the nodule was determined by thyroid ecography both before and after treatment. Evaluation of thyroid function was performed clinically and by T3 T4 and TSH determinations before therapy and during follow.up. AII patients had complete suppression of the surrounding thyroid parenchyma. Two cases of hypothyroidism were found in the first two years of follow-up. We have no explanation for this fact since extranodular thyroid tissue was suppressed and the patients were receiving oral triiodothyronine during radioidine treatment. The nodules decreasedin size In 9 of 13 patients followed (average decrease 45% and disappeared in other 2. our findings suggest that solitary non-toxic AFTN should be treated with I131 particularly if complete suppression of the surrounding thyroid tissue is found. If complete disappearance of the nodule is considered desirable surgical removal must be performed.

    Se trataron 14 mujeres y un hombre, con adenomas tiroideos solitarios funcionalmente autónomos, no tóxicos, con I131 a una dosis promedio de 19.2 mCi. La gamagrafía tiroidea demostró hipercaptación del nódulo con supresión total del resto de la glándula. El tamaño del nódulo se determinó por medio de ecografía tiroidea antes y después del tratamiento, y su autonomía por la prueba de supresión con triyodotironina. El estado tiroideo se puso de presente clínicamente y por la medición de T3, T 4 y TSH en el plasma, antes de la terapia con el radiofármaco y durante la evolución postratamiento. En dos

  2. Rubber compounding and processing

    CSIR Research Space (South Africa)

    John, MJ

    2014-06-01

    Full Text Available This chapter presents an overview on the compounding and processing techniques of natural rubber compounds. The introductory portion deals with different types of rubbers and principles of rubber compounding. The primary and secondary fillers used...

  3. Amino acid sequence and biological characterization of BlatPLA₂, a non-toxic acidic phospholipase A₂ from the venom of the arboreal snake Bothriechis lateralis from Costa Rica.

    Science.gov (United States)

    Van der Laat, Marco; Fernández, Julián; Durban, Jordi; Villalobos, Eva; Camacho, Erika; Calvete, Juan J; Lomonte, Bruno

    2013-10-01

    Bothriechis is considered a monophyletic, basal genus of arboreal Neotropical pitvipers distributed across Middle America. The four species found in Costa Rica (B. lateralis, B. schlegeli, B. nigroviridis, B. supraciliaris) differ in their venom proteomic profiles, suggesting that different Bothriechis taxa have evolved diverse trophic strategies. In this study, we isolated a phospholipase A₂ (PLA₂) from B. lateralis venom, aiming at increasing our knowledge on the structural and functional characteristics of group II acidic PLA₂s, whose toxic actions are generally more restricted than those displayed by basic PLA₂s. The new acidic enzyme, BlatPLA₂, occurs as a monomer of 13,917 Da, in contrast to many basic group II PLA₂s which associate into dimers and often display myotoxicity and/or neurotoxicity. Its amino acid sequence of 122 residues predicts an isoelectric point of 4.7, and displays significant differences with previously characterized acidic PLA₂s, with which it shows a maximum sequence identity of 78%. BlatPLA₂ is catalytically active but appears to be devoid of major toxic activities, lacking intravenous or intracerebroventricular lethality, myotoxicity, in vitro anticoagulant activity, and platelet aggregation or inhibition effects. Phylogenetic relationships with similar group II enzymes suggest that BlatPLA₂ may represent a basal sequence to other acidic PLA₂s. Due to the metabolic cost of venom protein synthesis, the presence of a relatively abundant (9%) but non-toxic component is somewhat puzzling. Nevertheless, we hypothesize that BlatPLA₂ could have a role in the pre-digestion of prey, possibly having retained characteristics of ancestral PLA₂s without evolving towards potent toxicity. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Genetic and toxinological characterization of North Atlantic strains of the dinoflagellate Ostreopsis and allelopathic interactions with toxic and non-toxic species from the genera Prorocentrum, Coolia and Gambierdiscus.

    Science.gov (United States)

    García-Portela, María; Riobó, Pilar; Franco, José Mariano; Bañuelos, Rosa Mª; Rodríguez, Francisco

    2016-12-01

    The genus Ostreopsis includes several toxic species that can develop blooms in benthic ecosystems, with potential harmful consequences for human health and marine invertebrates. Despite of this, little is known about the allelopathic interactions between these organisms and other co-occurring microalgae that exploit similar spatial and nutrient resources in benthic ecosystems. The aim of this study was to follow these interactions in cultures of two Ostreopsis ribotypes with different toxin profiles (O. cf. ovata contained ovatoxins-a, b, c and e, while only ovatoxin-d was found in O .sp. "Lanzarote-type"), mixed with species of three benthic dinoflagellate genera (Coolia, Prorocentrum and Gambierdiscus), isolated from the same area (North East Atlantic, Canary Islands). In a first experiment, the potential allelopathic effects on growth rates were followed, in mixed cultures of Coolia monotis (a non toxic species) exposed to the clarified medium and to cells of O. sp."Lanzarote-type" and O. cf. ovata. Growth delayed in C. monotis was observed specially in clarified medium, while the O. sp. "Lanzarote-type" strain attained much lower densities in mixed cultures. In a second experiment, we examined the potential effects of clarified media from O. sp."Lanzarote-type" and O. cf. ovata on the adherence capacity in two toxic species (Prorocentrum hoffmannianum and Gambierdiscus excentricus). Contrasting effects were found: a significant increase of adherence capacity in P. hoffmannianum vs attachment decline in G. excentricus, that experienced also severe deleterious effects (cell lysis). Our results suggest the existence of weak to moderate allelopathic interactions between the studied organisms, although the outcome is dependent on the species involved. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Applications of stable isotopes in agriculture

    International Nuclear Information System (INIS)

    Koren'kov, D.A.; Faust, Kh.

    1977-01-01

    The stable isotope 15 N has become widely used in agricultural studies. With it one can determine the true uptake of fertilizer and soil nitrogen by different crops as a function of their particular biological characteristics. Under field conditions, the extent of fertilizer nitrogen uptake by plants does not as a rule exceed 50%, being less for winter cereals and significantly more for perennial grasses. Applied fertilizer nitrogen, by intensifying the mobilization processes, increases the mobility of soil nitrogen. As a result, the accessibility of soil nitrogen to plants increases, and there is a greater chance of its being lost through washing-out. A considerable fraction of fertilizer nitrogen (on average 20-30%) becomes fixed in the soil in compounds which are not easily hydrolized and hence not readily available to plants. Nitrogen fixed in fulvic acids and non-specific compounds is the most mobile and can be used by plants. Fertilizer nitrogen in the soil undergoes various changes, as a result of which some is lost in the form of gaseous compounds. A certain amount of fertilizer nitrogen may become lost through washing-out. On the basis of 15 N investigations, it is possible to find ways of increasing the effectiveness of nitrogenous fertilizers and reducing nitrogen losses - for example, fertilizer application closer to the beginning of the period of active utilization of nutrients by plants, selection of more efficient fertilizer forms and the use of nitrification inhibitors. The wider employment of 15 N in agricultural studies should become possible through the use of cheaper compounds depleted or slightly enriched in 15 N. (author)

  6. Stable configurations in social networks

    Science.gov (United States)

    Bronski, Jared C.; DeVille, Lee; Ferguson, Timothy; Livesay, Michael

    2018-06-01

    We present and analyze a model of opinion formation on an arbitrary network whose dynamics comes from a global energy function. We study the global and local minimizers of this energy, which we call stable opinion configurations, and describe the global minimizers under certain assumptions on the friendship graph. We show a surprising result that the number of stable configurations is not necessarily monotone in the strength of connection in the social network, i.e. the model sometimes supports more stable configurations when the interpersonal connections are made stronger.

  7. Development of Stable Isotope Technology

    International Nuclear Information System (INIS)

    Jeong, Do Young; Kim, Cheol Jung; Han, Jae Min

    2009-03-01

    KAERI has obtained an advanced technology with singular originality for laser stable isotope separation. Objectives for this project are to get production technology of Tl-203 stable isotope used for medical application and are to establish the foundation of the pilot system, while we are taking aim at 'Laser Isotope Separation Technology to make resistance to the nuclear proliferation'. And we will contribute to ensuring a nuclear transparency in the world society by taking part in a practical group of NSG and being collaboration with various international groups related to stable isotope separation technology

  8. Synthesis of highly stable and biocompatible gold nanoparticles for use as a new X-ray contrast agent.

    Science.gov (United States)

    Iranpour, Pooya; Ajamian, Maral; Safavi, Afsaneh; Iranpoor, Nasser; Abbaspour, Abdolkarim; Javanmardi, Sanaz

    2018-04-18

    This work reports a novel reduction procedure for the synthesis of Gum Arabic (GA) capped-gold nanoparticles (AuNPs) in glucosammonium formate as a new ionic liquid. The GA coated AuNPs show good stability in physiological media. The synthesized AuNPs were characterized by UV-Vis spectroscopy, transmission electron microscopy, dynamic light scattering and X-ray diffraction analysis. These stable AuNPs are introduced as a new contrast agent for X-ray Computed Tomography (X-ray CT). These nanoparticles have higher contrasting properties than the commercial contrast agent, Visipaque. The precursors used (Gum Arabic and glucose based-ionic liquid) for synthesis of AuNPs are biocompatible and non-toxic.

  9. Stable isotope research pool inventory

    International Nuclear Information System (INIS)

    1984-03-01

    This report contains a listing of electromagnetically separated stable isotopes which are available at the Oak Ridge National Laboratory for distribution for nondestructive research use on a loan basis. This inventory includes all samples of stable isotopes in the Research Materials Collection and does not designate whether a sample is out on loan or is in reprocessing. For some of the high abundance naturally occurring isotopes, larger amounts can be made available; for example, Ca-40 and Fe-56

  10. French days on stable isotopes

    International Nuclear Information System (INIS)

    2000-01-01

    These first French days on stable isotopes took place in parallel with the 1. French days of environmental chemistry. Both conferences had common plenary sessions. The conference covers all aspects of the use of stable isotopes in the following domains: medicine, biology, environment, tracer techniques, agronomy, food industry, geology, petroleum geochemistry, cosmo-geochemistry, archaeology, bio-geochemistry, hydrology, climatology, nuclear and particle physics, astrophysics, isotope separations etc.. Abstracts available on CD-Rom only. (J.S.)

  11. Stable isotope research pool inventory

    International Nuclear Information System (INIS)

    1982-01-01

    This report contains a listing of electromagnetically separated stable isotopes which are available for distribution within the United States for nondestructive research use from the Oak Ridge National Laboratory on a loan basis. This inventory includes all samples of stable isotopes in the Material Research Collection and does not designate whether a sample is out on loan or in reprocessing. For some of the high abundance naturally occurring isotopes, larger amounts can be made available; for example, Ca-40 and Fe-56

  12. Pharmaceuticals labelled with stable isotopes

    International Nuclear Information System (INIS)

    Krumbiegel, P.

    1986-11-01

    The relatively new field of pharmaceuticals labelled with stable isotopes is reviewed. Scientific, juridical, and ethical questions are discussed concerning the application of these pharmaceuticals in human medicine. 13 C, 15 N, and 2 H are the stable isotopes mainly utilized in metabolic function tests. Methodical contributions are given to the application of 2 H, 13 C, and 15 N pharmaceuticals showing new aspects and different states of development in the field under discussion. (author)

  13. Sanskrit Compound Processor

    Science.gov (United States)

    Kumar, Anil; Mittal, Vipul; Kulkarni, Amba

    Sanskrit is very rich in compound formation. Typically a compound does not code the relation between its components explicitly. To understand the meaning of a compound, it is necessary to identify its components, discover the relations between them and finally generate a paraphrase of the compound. In this paper, we discuss the automatic segmentation and type identification of a compound using simple statistics that results from the manually annotated data.

  14. Synthesis of deuterium-labelled compounds for FOTEK project

    International Nuclear Information System (INIS)

    Joergensen, O.; Egsgaard, H.; Larsen, E.

    1996-01-01

    In the FoTech project there have been utilized labelled compounds of stable isotopes as internal standards. Some of these compounds are commercially available ( 13 C-labelled PCB congeners, 13 C-labelled diethylstilbestrol for determination of anabolic steroids). Others, like D 9 -clenbuterol, D 3 -clenbuterol, D 3 -zeramol and D 3 -dimetridazol have been synthesized. General aspects of deuterium compounds labelling are considered. (EG)

  15. Introduction to Quality Control in a Compounding Pharmacy.

    Science.gov (United States)

    Allen, Loyd V

    2016-01-01

    A quality-based program is vital in every compounding pharmacy to ensure that each preparation is compounded properly and is stable for its expected duration of use. This article discusses quality control, quality assurance, continuous quality improvement, and also describes the components of an in-house (in-pharmacy) quality program, as well as the role of outside laboratories. Copyright© by International Journal of Pharmaceutical Compounding, Inc.

  16. Non-toxic novel route synthesis and characterization of nanocrystalline ZnS{sub x}Se{sub 1−x} thin films with tunable band gap characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Agawane, G.L., E-mail: agawaneganesh@gmail.com [Department of Materials Science and Engineering, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Shin, Seung Wook [Department of Materials Science and Engineering, KAIST, Daejeon 305-701 (Korea, Republic of); Vanalakar, S.A. [Department of Materials Science and Engineering, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Moholkar, A.V. [Electrochemical Mat. Lab., Department of Physics, Shivaji University, Kolhapur 416-004 (India); Gurav, K.V.; Suryawanshi, M.P. [Department of Materials Science and Engineering, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Lee, Jeong Yong [Department of Materials Science and Engineering, KAIST, Daejeon 305-701 (Korea, Republic of); Yun, Jae Ho, E-mail: yunjh92@kier.re.kr [Photovoltaic Research Group, KIER, Jang-Dong, Yuseong-Gu, Daejeon 305-343 (Korea, Republic of); Kim, Jin Hyeok, E-mail: jinhyeok@chonnam.ac.kr [Department of Materials Science and Engineering, Chonnam National University, Gwangju 500-757 (Korea, Republic of)

    2014-07-01

    Highlights: • A simple, inexpensive, and non-toxic CBD route is used to deposit ZnS thin films. • The ZnS{sub x}Se{sub 1−x} thin films formation takes place via annealing of ZnS thin films in Se atmosphere. • S/(S + Se) ratio found to be temperature dependent and easy tuning of band gap has been done by Se atom deposition. - Abstract: An environmentally benign chemical bath deposition (CBD) route was employed to deposit zinc sulfide (ZnS) thin films. The CBD-ZnS thin films were further selenized in a furnace at various temperatures viz. 200, 300, 400, and 500 °C and the S/(S + Se) ratio was found to be dependent on the annealing temperature. The effects of S/(S + Se) ratio on the structural, compositional and optical properties of the ZnS{sub x}Se{sub 1−x} (ZnSSe) thin films were investigated. EDS analysis showed that the S/(S + Se) ratio decreased from 0.8 to 0.6 when the film annealing temperature increased from 200 to 500 °C. The field emission scanning electron microscopy and atomic force microscopy studies showed that all the films were uniform, pin hole free, smooth, and adhered well to the glass substrate. The X-ray diffraction study on the ZnSSe thin films showed the formation of the cubic phase, except for the unannealed ZnSSe thin film, which showed an amorphous phase. The X-ray photoelectron spectroscopy revealed Zn-S, Zn-Se, and insignificant Zn-OH bonds formation from the Zn 2p{sub 3/2}, S 2p, Se 3d{sub 5/2}, and O 1s atomic states, respectively. The ultraviolet–visible spectroscopy study showed ∼80% transmittance in the visible region for all the ZnSSe thin films having various absorption edges. The tuning of the band gap energy of the ZnSSe thin films was carried out by selenizing CBD-ZnS thin films, and as the S/(S + Se) ratio decreased from 0.8 to 0.6, the band gap energy decreased from 3.20 to 3.12 eV.

  17. Application of biotechnology for treatment of nitrogen compounds in gold mill effluents

    International Nuclear Information System (INIS)

    Kapoor, A.; Gould, W.D.; Bedard, P.; Morin, K.

    2004-01-01

    This paper presents the results of a research study that is being conducted by the Mine Effluents Program, Mining and Mineral Science Laboratory (MMSL), Natural Resources Canada aimed at evaluating biotechnology processes for the treatment of nitrogen compounds such as thiocyanide (CNS) and ammonia (NH 4- N) which are present in gold mill effluents. A sequencing batch reactor (SBR) technology, commonly used for the biological treatment of municipal and industrial effluents, was used in this study. In the SBR process, the micro-organisms were able to degrade CNS to NH 4- N and NH 4- N to nitrate (NO 3- N) at operating conditions of two 12 h treatment cycles per day, with pH maintained in the 7.4 to 7.6 range, and at room temperature (approximately 21 o C) and also at 12 o C. The end products of CNS and NH 4- N biological oxidation were NO 3- N and sulphate (SO 4 ) that are relatively non-toxic. Partial removal of NO 3- N was achieved by biological denitrification reactions in the SBR process. The SBR process effluent was measured to be non-toxic to rainbow trout based on the 96 h acute toxicity test. The microbial consortium isolated from the SBR treating a simulated effluent was able to effectively oxidize CNS and NH 4- N to NO 3- N in water samples (under batch conditions) collected at three mine sites located in Quebec, the Northwest Territories, and Yukon. (author)

  18. [Current Treatment of Stable Angina].

    Science.gov (United States)

    Toggweiler, Stefan; Jamshidi, Peiman; Cuculi, Florim

    2015-06-17

    Current therapy for stable angina includes surgical and percutaneous revascularization, which has been improved tremendously over the last decades. Smoking cessation and regular exercise are the cornerstone for prevention of further cerebrovascular events. Medical treatment includes treatment of cardiovascular risk factors and antithrombotic management, which can be a challenge in some patients. Owing to the fact the coronary revascularization is readily accessible these days in many industrialized countries, the importance of antianginal therapy has decreased over the past years. This article presents a contemporary overview of the management of patients with stable angina in the year 2015.

  19. Possibility of stable quark stars

    International Nuclear Information System (INIS)

    Bowers, R.L.; Gleeson, A.M.; Pedigo, R.D.

    1976-08-01

    A recent zero temperature equation of state which contains quark-partons separated from conventional baryons by a phase transition is used to investigate the stability of quark stars. The sensitivity to the input physics is also considered. The conclusions, which are found to be relatively model independent, indicate that a separately identifiable class of stable objects called quark stars does not exist

  20. Radiation-stable polyolefin compositions

    International Nuclear Information System (INIS)

    Rekers, J.W.

    1986-01-01

    This invention relates to compositions of olefinic polymers suitable for high energy radiation treatment. In particular, the invention relates to olefinic polymer compositions that are stable to sterilizing dosages of high energy radiation such as a gamma radiation. Stabilizers are described that include benzhydrol and benzhydrol derivatives; these stabilizers may be used alone or in combination with secondary antioxidants or synergists

  1. Evolutionary Structure Prediction of Stoichiometric Compounds

    Science.gov (United States)

    Zhu, Qiang; Oganov, Artem

    2014-03-01

    In general, for a given ionic compound AmBn\\ at ambient pressure condition, its stoichiometry reflects the valence state ratio between per chemical specie (i.e., the charges for each anion and cation). However, compounds under high pressure exhibit significantly behavior, compared to those analogs at ambient condition. Here we developed a method to solve the crystal structure prediction problem based on the evolutionary algorithms, which can predict both the stable compounds and their crystal structures at arbitrary P,T-conditions, given just the set of chemical elements. By applying this method to a wide range of binary ionic systems (Na-Cl, Mg-O, Xe-O, Cs-F, etc), we discovered a lot of compounds with brand new stoichimetries which can become thermodynamically stable. Further electronic structure analysis on these novel compounds indicates that several factors can contribute to this extraordinary phenomenon: (1) polyatomic anions; (2) free electron localization; (3) emergence of new valence states; (4) metallization. In particular, part of the results have been confirmed by experiment, which warrants that this approach can play a crucial role in new materials design under extreme pressure conditions. This work is funded by DARPA (Grants No. W31P4Q1210008 and W31P4Q1310005), NSF (EAR-1114313 and DMR-1231586).

  2. Toward Practical Secure Stable Matching

    Directory of Open Access Journals (Sweden)

    Riazi M. Sadegh

    2017-01-01

    Full Text Available The Stable Matching (SM algorithm has been deployed in many real-world scenarios including the National Residency Matching Program (NRMP and financial applications such as matching of suppliers and consumers in capital markets. Since these applications typically involve highly sensitive information such as the underlying preference lists, their current implementations rely on trusted third parties. This paper introduces the first provably secure and scalable implementation of SM based on Yao’s garbled circuit protocol and Oblivious RAM (ORAM. Our scheme can securely compute a stable match for 8k pairs four orders of magnitude faster than the previously best known method. We achieve this by introducing a compact and efficient sub-linear size circuit. We even further decrease the computation cost by three orders of magnitude by proposing a novel technique to avoid unnecessary iterations in the SM algorithm. We evaluate our implementation for several problem sizes and plan to publish it as open-source.

  3. Stable isotope research pool inventory

    International Nuclear Information System (INIS)

    1986-08-01

    This report contains a listing of electromagnetically separated stable isotopes which are available at the Oak Ridge National Laboratory for distribution for nondestructive research use on a loan basis. This inventory includes all samples of stable isotopes in the Research Materials Collection and does not designate whether a sample is out on loan or is in reprocessing. For some of the high-abundance, naturally occurring isotopes, larger amounts can be made available; for example, Ca-40 and Fe-56. All requests for the loan of samples should be submitted with a summary of the purpose of the loan to: Iotope Distribution Office, Oak Ridge National Laboratory, P.O. Box X, Oak Ridge, Tennessee 37831. Requests from non-DOE contractors and from foreign institutions require DOE approval

  4. Stable isotopes and the environment

    International Nuclear Information System (INIS)

    Krouse, H.R.

    1990-01-01

    Whereas traditionally, stable isotope research has been directed towards resource exploration and development, it is finding more frequent applications in helping to assess the impacts of resource utilization upon ecosystems. Among the many pursuits, two themes are evident: tracing the transport and conversions of pollutants in the environment and better understanding of the interplay among environmental receptors, e.g. food web studies. Stable isotope data are used primarily to identify the presence of pollutants in the environment and with a few exceptions, the consequence of their presence must be assessed by other techniques. Increasing attention has been given to the isotopic composition of humans with many potential applications in areas such as paleodiets, medicine, and criminology. In this brief overview examples are used from the Pacific Rim to illustrate the above concepts. 26 refs., 1 tab., 3 figs

  5. Towards stable acceleration in LINACS

    CERN Document Server

    Dubrovskiy, A D

    2014-01-01

    Ultra-stable and -reproducible high-energy particle beams with short bunches are needed in novel linear accelerators and, in particular, in the Compact Linear Collider CLIC. A passive beam phase stabilization system based on a bunch compression with a negative transfer matrix element R56 and acceleration at a positive off-crest phase is proposed. The motivation and expected advantages of the proposed scheme are outlined.

  6. Stable Structures for Distributed Applications

    OpenAIRE

    Eugen DUMITRASCU; Ion IVAN

    2008-01-01

    For distributed applications, we define the linear, tree and graph structure types with different variants and modalities to aggregate them. The distributed applications have assigned structures that through their characteristics influence the costs of stages for developing cycle and the costs for exploitation, transferred to each user. We also present the quality characteristics of a structure for a stable application, which is focused on stability characteristic. For that characteristic we ...

  7. Cytocompatible and water stable ultrafine protein fibers for tissue engineering

    Science.gov (United States)

    Jiang, Qiuran

    This dissertation proposal focuses on the development of cytocompatible and water stable protein ultrafine fibers for tissue engineering. The protein-based ultrafine fibers have the potential to be used for biomedicine, due to their biocompatibility, biodegradability, similarity to natural extracellular matrix (ECM) in physical structure and chemical composition, and superior adsorption properties due to their high surface to volume ratio. However, the current technologies to produce the protein-based ultrafine fibers for biomedical applications still have several problems. For instance, the current electrospinning and phase separation technologies generate scaffolds composed of densely compacted ultrafine fibers, and cells can spread just on the surface of the fiber bulk, and hardly penetrate into the inner sections of scaffolds. Thus, these scaffolds can merely emulate the ECM as a two dimensional basement membrane, but are difficult to mimic the three dimensional ECM stroma. Moreover, the protein-based ultrafine fibers do not possess sufficient water stability and strength for biomedical applications, and need modifications such as crosslinking. However, current crosslinking methods are either high in toxicity or low in crosslinking efficiency. To solve the problems mentioned above, zein, collagen, and gelatin were selected as the raw materials to represent plant proteins, animal proteins, and denatured proteins in this dissertation. A benign solvent system was developed specifically for the fabrication of collagen ultrafine fibers. In addition, the gelatin scaffolds with a loose fibrous structure, high cell-accessibility and cell viability were produced by a novel ultralow concentration phase separation method aiming to simulate the structure of three dimensional (3D) ECM stroma. Non-toxic crosslinking methods using citric acid as the crosslinker were also developed for electrospun or phase separated scaffolds from these three proteins, and proved to be

  8. Thermal decomposition of zirconium compounds with some aromatic hydroxycarboxylic acids

    Energy Technology Data Exchange (ETDEWEB)

    Koshel, A V; Malinko, L A; Karlysheva, K F; Sheka, I A; Shchepak, N I [AN Ukrainskoj SSR, Kiev. Inst. Obshchej i Neorganicheskoj Khimii

    1980-02-01

    By the thermogravimetry method investigated are processes of thermal decomposition of different zirconium compounds with mandelic, parabromomandelic, salicylic and sulphosalicylic acids. For identification of decomposition products the specimens have been kept at the temperature of effects up to the constant weight. Taken are IR-spectra, rentgenoarams, carried out is elementary analysis of decomposition products. It is stated that thermal decomposition of the investigated compounds passes in stages; the final product of thermolysis is ZrO/sub 2/. Nonhydrolized compounds are stable at heating in the air up to 200-265 deg. Hydroxy compounds begin to decompose at lower temperature (80-100 deg).

  9. Electrospun water-stable zein/ethyl cellulose composite nanofiber and its drug release properties

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Hangyi; Wang, Qingqing; Li, Guohui [Key Laboratory of Eco-textiles, Jiangnan University, Wuxi (China); Qiu, Yuyu [Key Laboratory of Eco-textiles, Jiangnan University, Wuxi (China); Laboratory of Natural Medicine, Wuxi Medical School, Jiangnan University (China); Wei, Qufu, E-mail: qfwei@jiangnan.edu.cn [Key Laboratory of Eco-textiles, Jiangnan University, Wuxi (China)

    2017-05-01

    A simple and cost-effective way to prepare water-stable zein-based nanofibers for potential drug delivery was presented in this article. Corn protein zein was co-electrospun with hydrophobic ethyl cellulose. Indomethacin, as a model drug, was incorporated in situ into the composite nanofibers. Scanning electron microscopy and element mapping revealed the morphologies of drug-loaded nanofibers and drug distribution, respectively. Fourier transform infrared spectra confirmed the physical blending among the components. Differential scanning calorimetry and X-ray diffraction demonstrated the physical state of drug and polymers in the nanofiber matrix. The composite nanofibers showed a sustained diffusion-controlled release according to the results of in vitro dissolution tests. - Highlights: • A simple, non-toxic and cost-effective way to improve water stability of zein nanofibers was proposed. • Electrospun zein/ethyl cellulose nanofibers with improved water stability and mechanical strength were prepared. • Indomethacin was homogeneously distributed in the zein/ethyl cellulose nanofibers with no aggregation or cluster. • The zein/ethyl cellulose nanofibers presented a sustained drug release profile, following Fickican diffusion mechanism.

  10. Shelf-stable foods through irradiation processing

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-11-01

    This survey has been produced from a database on analytical reference materials of biological and environmental origin, which is maintained at the International Atomic Energy Agency. It is an updated version of earlier reports, the last published in 1990. The information presented refers mostly to reference materials for trace element constituents; however, information is also included on a number of other selected measurands of relevance to IAEA programmes, i.e. radionuclides, stable isotopes, anions, cations, organometallic compounds and organic contaminants. The database presently contains over 10,000 analyte values for 455 measurands in 650 reference materials produced by 30 different suppliers. Additional information on the cost of the materials, the unit size supplied, and recommended minimum weight of material for analysis is also provided, if this information is available to the authors. It is expected that this survey will help analysts to select reference materials for quality assurance purposes that match as closely as possible, with respect to matrix type and concentrations of the measurands of interest, their samples to be analyzed. 22 refs, 2 tabs.

  11. Shelf-stable foods through irradiation processing

    International Nuclear Information System (INIS)

    1995-11-01

    This survey has been produced from a database on analytical reference materials of biological and environmental origin, which is maintained at the International Atomic Energy Agency. It is an updated version of earlier reports, the last published in 1990. The information presented refers mostly to reference materials for trace element constituents; however, information is also included on a number of other selected measurands of relevance to IAEA programmes, i.e. radionuclides, stable isotopes, anions, cations, organometallic compounds and organic contaminants. The database presently contains over 10,000 analyte values for 455 measurands in 650 reference materials produced by 30 different suppliers. Additional information on the cost of the materials, the unit size supplied, and recommended minimum weight of material for analysis is also provided, if this information is available to the authors. It is expected that this survey will help analysts to select reference materials for quality assurance purposes that match as closely as possible, with respect to matrix type and concentrations of the measurands of interest, their samples to be analyzed. 22 refs, 2 tabs

  12. Organic synthesis with stable isotopes

    International Nuclear Information System (INIS)

    Daub, G.H.; Kerr, V.N.; Williams, D.L.; Whaley, T.W.

    1978-01-01

    Some general considerations concerning organic synthesis with stable isotopes are presented. Illustrative examples are described and discussed. The examples include DL-2-amino-3-methyl- 13 C-butanoic-3,4- 13 C 2 acid (DL-valine- 13 C 3 ); methyl oleate-1- 13 C; thymine-2,6- 13 C 2 ; 2-aminoethanesulfonic- 13 C acid (taurine- 13 C); D-glucose-6- 13 C; DL-2-amino-3-methylpentanoic-3,4- 13 C 2 acid (DL-isoleucine- 13 C 2 ); benzidine- 15 N 2 ; and 4-ethylsulfonyl-1-naphthalene-sulfonamide- 15 N

  13. The natural compound silvestrol is a potent inhibitor of Ebola virus replication.

    Science.gov (United States)

    Biedenkopf, Nadine; Lange-Grünweller, Kerstin; Schulte, Falk W; Weißer, Aileen; Müller, Christin; Becker, Dirk; Becker, Stephan; Hartmann, Roland K; Grünweller, Arnold

    2017-01-01

    The DEAD-box RNA helicase eIF4A, which is part of the heterotrimeric translation initiation complex in eukaryotes, is an important novel drug target in cancer research because its helicase activity is required to unwind extended and highly structured 5'-UTRs of several proto-oncogenes. Silvestrol, a natural compound isolated from the plant Aglaia foveolata, is a highly efficient, non-toxic and specific inhibitor of eIF4A. Importantly, 5'-capped viral mRNAs often contain structured 5'-UTRs as well, which may suggest a dependence on eIF4A for their translation by the host protein synthesis machinery. In view of the recent Ebola virus (EBOV) outbreak in West Africa, the identification of potent antiviral compounds is urgently required. Since Ebola mRNAs are 5'-capped and harbor RNA secondary structures in their extended 5'-UTRs, we initiated a BSL4 study to analyze silvestrol in EBOV-infected Huh-7 cells and in primary human macrophages for its antiviral activity. We observed that silvestrol inhibits EBOV infection at low nanomolar concentrations, as inferred from large reductions of viral titers. This correlated with an almost complete disappearance of EBOV proteins, comparable in effect to the translational shutdown of expression of the proto-oncoprotein PIM1, a cellular kinase known to be affected by silvestrol. Effective silvestrol concentrations were non-toxic in the tested cell systems. Thus, silvestrol appears to be a promising first-line drug for the treatment of acute EBOV and possibly other viral infections. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Stable cosmology in chameleon bigravity

    Science.gov (United States)

    De Felice, Antonio; Mukohyama, Shinji; Oliosi, Michele; Watanabe, Yota

    2018-02-01

    The recently proposed chameleonic extension of bigravity theory, by including a scalar field dependence in the graviton potential, avoids several fine-tunings found to be necessary in usual massive bigravity. In particular it ensures that the Higuchi bound is satisfied at all scales, that no Vainshtein mechanism is needed to satisfy Solar System experiments, and that the strong coupling scale is always above the scale of cosmological interest all the way up to the early Universe. This paper extends the previous work by presenting a stable example of cosmology in the chameleon bigravity model. We find a set of initial conditions and parameters such that the derived stability conditions on general flat Friedmann background are satisfied at all times. The evolution goes through radiation-dominated, matter-dominated, and de Sitter eras. We argue that the parameter space allowing for such a stable evolution may be large enough to encompass an observationally viable evolution. We also argue that our model satisfies all known constraints due to gravitational wave observations so far and thus can be considered as a unique testing ground of gravitational wave phenomenologies in bimetric theories of gravity.

  15. Stable Heavy Hadrons in ATLAS

    CERN Document Server

    Mackeprang, Rasmus

    2007-01-01

    Several extensions to the SM feature heavy long-lived particles with masses of O(10^2-10^3 GeV) and mean lifetimes fulfilling $CT \\geq 10m$. Among such theories are supersymmetric scenarios as well as extra-dimensional models in which the heavy new particles are seen as Kaluza-Klein excitations of the well-known SM particles. Such particles will, from the point of view of a collider experiment be seen as stable. This thesis is concerned with the case where the exotic heavy particles emph{can} be considered stable while traversing the detector. Specifically the case is considered where the particles in question carry the charge of the strong nuclear force, commonly referred to as emph{colour charge}. A simulation kit has been developed using GEANT4. This framework is the current standard in experimental particle physics for the simulation of interactions of particles with matter, and it is used extensively for detector simulation. The simulation describes the interactions of these particles with matter which i...

  16. Photocatalytic Degradation of 4-Nitrophenol by C, N-TiO2: Degradation Efficiency vs. Embryonic Toxicity of the Resulting Compounds

    Science.gov (United States)

    Osin, Oluwatomiwa A.; Yu, Tianyu; Cai, Xiaoming; Jiang, Yue; Peng, Guotao; Cheng, Xiaomei; Li, Ruibin; Qin, Yao; Lin, Sijie

    2018-06-01

    The photocatalytic activity of TiO2 based photocatalysts can be improved by structural modification and elemental doping. In this study, through rational design, one type of carbon and nitrogen co-doped TiO2 (C, N-TiO2) photocatalyst with mesoporous structure was synthesized with improved photocatalytic activity in degrading 4-nitrophenol under simulated sunlight irradiation. The photocatalytic degradation efficiency of the C, N-TiO2 was much higher than the anatase TiO2 (A-TiO2) based on absorbance and HPLC analyses. Moreover, using zebrafish embryos, we showed that the intermediate degradation compounds generated by photocatalytic degradation of 4-nitrophenol had higher toxicity than the parent compound. A repeated degradation process was necessary to render complete degradation and non-toxicity to the zebrafish embryos. Our results demonstrated the importance of evaluating the photocatalytic degradation efficiency in conjunction with the toxicity assessment of the degradation compounds.

  17. Tritium labeling of simple 7-membered ring compounds

    International Nuclear Information System (INIS)

    Hiltunen, J.; Peng, C.T.; Yang, Z.C.

    1990-01-01

    Seven-membered ring compounds, from cycloheptane to complex ring structures containing heteroatoms, substituents and fused phenyl rings, were labeled with tritium, using activated and adsorbed tritium. The 7-membered ring structures are generally stable towards reactions with tritium, which allows compounds like 1-benzosuberone, 1-aza-2-methoxy-1-cycloheptane, iminostilbene and clozapine to be labeled to reasonably high specific activities. The best method varies greatly from compound to compound. By optimizing the labeling conditions and use of efficient support exceptionally good results can be obtained. The Pd-on-alumina support gives consistently higher specific activity and less radioimpurity than other supports. Even molecules containing carbon-halogen bond and hydrogen bound to nitrogen can usually be labeled with tritium at stable positions and without dehalogenation. (author)

  18. Medical Applications and Toxicities of Gallium Compounds

    Directory of Open Access Journals (Sweden)

    Christopher R. Chitambar

    2010-05-01

    Full Text Available Over the past two to three decades, gallium compounds have gained importance in the fields of medicine and electronics. In clinical medicine, radioactive gallium and stable gallium nitrate are used as diagnostic and therapeutic agents in cancer and disorders of calcium and bone metabolism. In addition, gallium compounds have displayed anti-inflammatory and immunosuppressive activity in animal models of human disease while more recent studies have shown that gallium compounds may function as antimicrobial agents against certain pathogens. In a totally different realm, the chemical properties of gallium arsenide have led to its use in the semiconductor industry. Gallium compounds, whether used medically or in the electronics field, have toxicities. Patients receiving gallium nitrate for the treatment of various diseases may benefit from such therapy, but knowledge of the therapeutic index of this drug is necessary to avoid clinical toxicities. Animals exposed to gallium arsenide display toxicities in certain organ systems suggesting that environmental risks may exist for individuals exposed to this compound in the workplace. Although the arsenic moiety of gallium arsenide appears to be mainly responsible for its pulmonary toxicity, gallium may contribute to some of the detrimental effects in other organs. The use of older and newer gallium compounds in clinical medicine may be advanced by a better understanding of their mechanisms of action, drug resistance, pharmacology, and side-effects. This review will discuss the medical applications of gallium and its mechanisms of action, the newer gallium compounds and future directions for development, and the toxicities of gallium compounds in current use.

  19. Stable isotope mass spectrometry in petroleum exploration

    International Nuclear Information System (INIS)

    Mathur, Manju

    1997-01-01

    The stable isotope mass spectrometry plays an important role to evaluate the stable isotopic composition of hydrocarbons. The isotopic ratios of certain elements in petroleum samples reflect certain characteristics which are useful for petroleum exploration

  20. DNA stable-isotope probing (DNA-SIP).

    Science.gov (United States)

    Dunford, Eric A; Neufeld, Josh D

    2010-08-02

    DNA stable-isotope probing (DNA-SIP) is a powerful technique for identifying active microorganisms that assimilate particular carbon substrates and nutrients into cellular biomass. As such, this cultivation-independent technique has been an important methodology for assigning metabolic function to the diverse communities inhabiting a wide range of terrestrial and aquatic environments. Following the incubation of an environmental sample with stable-isotope labelled compounds, extracted nucleic acid is subjected to density gradient ultracentrifugation and subsequent gradient fractionation to separate nucleic acids of differing densities. Purification of DNA from cesium chloride retrieves labelled and unlabelled DNA for subsequent molecular characterization (e.g. fingerprinting, microarrays, clone libraries, metagenomics). This JoVE video protocol provides visual step-by-step explanations of the protocol for density gradient ultracentrifugation, gradient fractionation and recovery of labelled DNA. The protocol also includes sample SIP data and highlights important tips and cautions that must be considered to ensure a successful DNA-SIP analysis.

  1. Stable rotating dipole solitons in nonlocal media

    DEFF Research Database (Denmark)

    Lopez-Aguayo, Servando; Skupin, Stefan; Desyatnikov, Anton S.

    2006-01-01

    We present the first example of stable rotating two-soliton bound states in nonlinear optical media with nonlocal response. We show that, in contrast to media with local response, nonlocality opens possibilities to generate stable azimuthons.......We present the first example of stable rotating two-soliton bound states in nonlinear optical media with nonlocal response. We show that, in contrast to media with local response, nonlocality opens possibilities to generate stable azimuthons....

  2. Tempered stable laws as random walk limits

    OpenAIRE

    Chakrabarty, Arijit; Meerschaert, Mark M.

    2010-01-01

    Stable laws can be tempered by modifying the L\\'evy measure to cool the probability of large jumps. Tempered stable laws retain their signature power law behavior at infinity, and infinite divisibility. This paper develops random walk models that converge to a tempered stable law under a triangular array scheme. Since tempered stable laws and processes are useful in statistical physics, these random walk models can provide a basic physical model for the underlying physical phenomena.

  3. Stable States of Biological Organisms

    Science.gov (United States)

    Yukalov, V. I.; Sornette, D.; Yukalova, E. P.; Henry, J.-Y.; Cobb, J. P.

    2009-04-01

    A novel model of biological organisms is advanced, treating an organism as a self-consistent system subject to a pathogen flux. The principal novelty of the model is that it describes not some parts, but a biological organism as a whole. The organism is modeled by a five-dimensional dynamical system. The organism homeostasis is described by the evolution equations for five interacting components: healthy cells, ill cells, innate immune cells, specific immune cells, and pathogens. The stability analysis demonstrates that, in a wide domain of the parameter space, the system exhibits robust structural stability. There always exist four stable stationary solutions characterizing four qualitatively differing states of the organism: alive state, boundary state, critical state, and dead state.

  4. Super-stable Poissonian structures

    International Nuclear Information System (INIS)

    Eliazar, Iddo

    2012-01-01

    In this paper we characterize classes of Poisson processes whose statistical structures are super-stable. We consider a flow generated by a one-dimensional ordinary differential equation, and an ensemble of particles ‘surfing’ the flow. The particles start from random initial positions, and are propagated along the flow by stochastic ‘wave processes’ with general statistics and general cross correlations. Setting the initial positions to be Poisson processes, we characterize the classes of Poisson processes that render the particles’ positions—at all times, and invariantly with respect to the wave processes—statistically identical to their initial positions. These Poisson processes are termed ‘super-stable’ and facilitate the generalization of the notion of stationary distributions far beyond the realm of Markov dynamics. (paper)

  5. Super-stable Poissonian structures

    Science.gov (United States)

    Eliazar, Iddo

    2012-10-01

    In this paper we characterize classes of Poisson processes whose statistical structures are super-stable. We consider a flow generated by a one-dimensional ordinary differential equation, and an ensemble of particles ‘surfing’ the flow. The particles start from random initial positions, and are propagated along the flow by stochastic ‘wave processes’ with general statistics and general cross correlations. Setting the initial positions to be Poisson processes, we characterize the classes of Poisson processes that render the particles’ positions—at all times, and invariantly with respect to the wave processes—statistically identical to their initial positions. These Poisson processes are termed ‘super-stable’ and facilitate the generalization of the notion of stationary distributions far beyond the realm of Markov dynamics.

  6. Periodicity of the stable isotopes

    CERN Document Server

    Boeyens, J C A

    2003-01-01

    It is demonstrated that all stable (non-radioactive) isotopes are formally interrelated as the products of systematically adding alpha particles to four elementary units. The region of stability against radioactive decay is shown to obey a general trend based on number theory and contains the periodic law of the elements as a special case. This general law restricts the number of what may be considered as natural elements to 100 and is based on a proton:neutron ratio that matches the golden ratio, characteristic of biological and crystal growth structures. Different forms of the periodic table inferred at other proton:neutron ratios indicate that the electronic configuration of atoms is variable and may be a function of environmental pressure. Cosmic consequences of this postulate are examined. (author)

  7. Stable massive particles at colliders

    Energy Technology Data Exchange (ETDEWEB)

    Fairbairn, M.; /Stockholm U.; Kraan, A.C.; /Pennsylvania U.; Milstead, D.A.; /Stockholm U.; Sjostrand, T.; /Lund U.; Skands, P.; /Fermilab; Sloan, T.; /Lancaster U.

    2006-11-01

    We review the theoretical motivations and experimental status of searches for stable massive particles (SMPs) which could be sufficiently long-lived as to be directly detected at collider experiments. The discovery of such particles would address a number of important questions in modern physics including the origin and composition of dark matter in the universe and the unification of the fundamental forces. This review describes the techniques used in SMP-searches at collider experiments and the limits so far obtained on the production of SMPs which possess various colour, electric and magnetic charge quantum numbers. We also describe theoretical scenarios which predict SMPs, the phenomenology needed to model their production at colliders and interactions with matter. In addition, the interplay between collider searches and open questions in cosmology such as dark matter composition are addressed.

  8. Some functional limit theorems for compound Cox processes

    Energy Technology Data Exchange (ETDEWEB)

    Korolev, Victor Yu. [Faculty of Computational Mathematics and Cybernetics, Moscow State University, Moscow (Russian Federation); Institute of Informatics Problems FRC CSC RAS (Russian Federation); Chertok, A. V. [Faculty of Computational Mathematics and Cybernetics, Moscow State University, Moscow (Russian Federation); Euphoria Group LLC (Russian Federation); Korchagin, A. Yu. [Faculty of Computational Mathematics and Cybernetics, Moscow State University, Moscow (Russian Federation); Kossova, E. V. [Higher School of Economics National Research University, Moscow (Russian Federation); Zeifman, Alexander I. [Vologda State University, S.Orlova, 6, Vologda (Russian Federation); Institute of Informatics Problems FRC CSC RAS, ISEDT RAS (Russian Federation)

    2016-06-08

    An improved version of the functional limit theorem is proved establishing weak convergence of random walks generated by compound doubly stochastic Poisson processes (compound Cox processes) to Lévy processes in the Skorokhod space under more realistic moment conditions. As corollaries, theorems are proved on convergence of random walks with jumps having finite variances to Lévy processes with variance-mean mixed normal distributions, in particular, to stable Lévy processes.

  9. Some functional limit theorems for compound Cox processes

    International Nuclear Information System (INIS)

    Korolev, Victor Yu.; Chertok, A. V.; Korchagin, A. Yu.; Kossova, E. V.; Zeifman, Alexander I.

    2016-01-01

    An improved version of the functional limit theorem is proved establishing weak convergence of random walks generated by compound doubly stochastic Poisson processes (compound Cox processes) to Lévy processes in the Skorokhod space under more realistic moment conditions. As corollaries, theorems are proved on convergence of random walks with jumps having finite variances to Lévy processes with variance-mean mixed normal distributions, in particular, to stable Lévy processes.

  10. Titanium zirconium and hafnium coordination compounds with vanillin thiosemicarbazone

    International Nuclear Information System (INIS)

    Konunova, Ts.B.; Kudritskaya, S.A.

    1987-01-01

    Coordination compounds of titanium zirconium and hafnium tetrachlorides with vanillin thiosemicarbazone of MCl 4 x nLig composition, where n=1.5, 4 for titanium and 1, 2, 4 for zirconium and hafnium, are synthesized. Molar conductivity of ethanol solutions is measured; IR spectroscopic and thermochemical investigation are carried out. The supposition about ligand coordination via sulfur and azomethine nitrogen atoms is made. In all cases hafnium forms stable compounds than zirconium

  11. The Myopic Stable Set for Social Environments

    NARCIS (Netherlands)

    Demuynck, Thomas; Herings, P. Jean-Jacques; Saulle, Riccardo; Seel, Christian

    2017-01-01

    We introduce a new solution concept for models of coalition formation, called the myopic stable set. The myopic stable set is defined for a very general class of social environments and allows for an infinite state space. We show that the myopic stable set exists and is non-empty. Under minor

  12. Effectiveness and risks of stable iodine prophylaxis

    International Nuclear Information System (INIS)

    Waight, P.J.

    1995-01-01

    The factors upon which the efficacy of stable iodine prophylaxis depends are reviewed, with particular reference to the dose of stable iodine, the timing of the dose, the influence of dietary iodine and the impact of the other prospective actions. The risks of stable iodine ingestion are estimated, and their application to the principle of Justification in outlined. (Author)

  13. Temperature and Humidity Control in Livestock Stables

    DEFF Research Database (Denmark)

    Hansen, Michael; Andersen, Palle; Nielsen, Kirsten M.

    2010-01-01

    The paper describes temperature and humidity control of a livestock stable. It is important to have a correct air flow pattern in the livestock stable in order to achieve proper temperature and humidity control as well as to avoid draught. In the investigated livestock stable the air flow...

  14. A stable enol from a 6-substituted benzanthrone and its unexpected behaviour under acidic conditions

    Directory of Open Access Journals (Sweden)

    Marc Debeaux

    2009-06-01

    Full Text Available Treatment of benzanthrone (1 with biphenyl-2-yl lithium leads to the surprisingly stable enol 4, which is converted by dehydrogenation into the benzanthrone derivative 7. Under acidic conditions 4 isomerises to the spiro compound 11 and the bicyclo[4.3.1]decane derivative 12. Furthermore, the formation of 7 and the hydrogenated compound 13 is observed. A mechanism for the formation of the reaction products is proposed and supported by DFT calculations.

  15. A stable-isotope mass spectrometry-based metabolic footprinting approach to analyze exudates from phytoplankton

    DEFF Research Database (Denmark)

    Weber, Ralf J. M.; Selander, Erik; Sommer, Ulf

    2013-01-01

    Phytoplankton exudates play an important role in pelagic ecology and biogeochemical cycles of elements. Exuded compounds fuel the microbial food web and often encompass bioactive secondary metabolites like sex pheromones, allelochemicals, antibiotics, or feeding attractants that mediate biological...... interactions. Despite this importance, little is known about the bioactive compounds present in phytoplankton exudates. We report a stable-isotope metabolic footprinting method to characterise exudates from aquatic autotrophs. Exudates from 13C-enriched alga were concentrated by solid phase extraction...

  16. Air-stable compact of cobalt-rare earth alloy particles and method

    International Nuclear Information System (INIS)

    Smeggil, J.C.; Charles, R.J.

    1975-01-01

    A process is described for producing novel air-stable magnetic products. An organometallic compound which decomposes at a temperature below 500 0 C is mixed with particles of a transition metal-rare earth alloy. The resulting mixture is pressed to form a green body, which is then heated to decompose the organometallic compound to produce a metal vapor that deposits an interconnecting metal coating on the exposed surfaces of the pressed particles. (U.S.)

  17. Behaviour of organic sulfur compounds in HPLC

    International Nuclear Information System (INIS)

    Freyholdt, T.

    1982-01-01

    The retention behaviour of organic sulfur compounds in the reverse-bonded-phase chromatography is characterized by determining the retention indices according to Kovats. The results of these studies show that the solubility of organic compounds in the eluting agent and the molar sorption surfaces of the solutes are the main factors determining the retention behaviour. Knowledge of the retention indices of above-mentioned compounds allows a quick interpretation of chromatograms obtained through a product analysis of γ-irradiated aqueous solutions of organic sulfur compounds. Dithia compounds of the type CH 3 -S-(CH 2 )sub(n)-S-Ch 3 (1 1. 2,4-Dithiapentane (n = 1) however will yield primarily monothio-S-methyl formate as a stable end product. The formation of oxygenic reaction products proceeds via sulfur-centred radical kations. Spin trapping experiments with nitroxyl radicals show that it is possible to trap radiation-chemically produced radicals of sulfurous substrates, but the thus obtained adducts with half-life periods of 4-5 min. cannot be identified by means of NMR, IR or mass spectroscopy. (orig.) [de

  18. Compounding around the world.

    Science.gov (United States)

    Vail, Jane

    2008-01-01

    Pharmaceutical compounding is universal in its prevalence. Variations in disease patterns, culture, and tradition; the role of government in health care; and the availability of essential equipment and required agents shape a compounding profile unique to each country worldwide. In the following reflections, pharmacists form Argentina, Belgium, Colombia, Germany, Puerto Rico, Spain, and the United States describe their experiences in the compounding setting unique to their practice and their nation. The unifying theme in their comments is the dedication of each contributor to enabling recovery and ensuring the good health of his or her clients.

  19. Compound Semiconductor Radiation Detectors

    CERN Document Server

    Owens, Alan

    2012-01-01

    Although elemental semiconductors such as silicon and germanium are standard for energy dispersive spectroscopy in the laboratory, their use for an increasing range of applications is becoming marginalized by their physical limitations, namely the need for ancillary cooling, their modest stopping powers, and radiation intolerance. Compound semiconductors, on the other hand, encompass such a wide range of physical and electronic properties that they have become viable competitors in a number of applications. Compound Semiconductor Radiation Detectors is a consolidated source of information on all aspects of the use of compound semiconductors for radiation detection and measurement. Serious Competitors to Germanium and Silicon Radiation Detectors Wide-gap compound semiconductors offer the ability to operate in a range of hostile thermal and radiation environments while still maintaining sub-keV spectral resolution at X-ray wavelengths. Narrow-gap materials offer the potential of exceeding the spectral resolutio...

  20. Hexavalent Chromium Compounds

    Science.gov (United States)

    Learn about chromium, exposure to which can increase your risk of lung cancer and cancer of the paranasal sinuses and nasal cavity. Hexavalent chromium compounds have been used as corrosion inhibitors in a wide variety of products and processes.

  1. MEA 86 Compound data

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data file contains the full raw parameter data for the 86 compounds tested in the developmental MEA assay, as well as Area Under the Curve (AUC) calculations...

  2. Moltex Energy's stable salt reactors

    International Nuclear Information System (INIS)

    O'Sullivan, R.; Laurie, J.

    2016-01-01

    A stable salt reactor is a molten salt reactor in which the molten fuel salt is contained in fuel rods. This concept was invented in 1951 and re-discovered and improved recently by Moltex Energy Company. The main advantage of using molten salt fuel is that the 2 problematic fission products cesium and iodine do not exist in gaseous form but rather in a form of a salt that present no danger in case of accident. Another advantage is the strongly negative temperature coefficient for reactivity which means the reactor self-regulates. The feasibility studies have been performed on a molten salt fuel composed of sodium chloride and plutonium/uranium/lanthanide/actinide trichloride. The coolant fluid is a mix of sodium and zirconium fluoride salts that will need low flow rates. The addition of 1 mol% of metal zirconium to the coolant fluid reduces the risk of corrosion with standard steels and the addition of 2% of hafnium reduces the neutron dose. The temperature of the coolant is expected to reach 650 Celsius degrees at the exit of the core. This reactor is designed to be modular and it will be able to burn actinides. (A.C.)

  3. Rare stable isotopes in meteorites

    International Nuclear Information System (INIS)

    Wilson, G.C.

    1981-01-01

    Secondary Ion Mass Spectrometry (SIMS) using accelerators has been applied with success to cosmic ray exposure ages and terrestrial residence times of meteorites by measuring cosmogenic nuclides of Be, Cl, and I. It is proposed to complement this work with experiments on rare stable isotopes, in the hope of setting constraints on the processes of solar nebula/meteoritic formation. The relevant species can be classified as: a) daughter products of extinct nuclides (halflife less than or equal to 2 x 10 8 y) -chronology of the early solar system; b) products of high temperature astrophysical processes - different components incorporated into the solar nebula; and c) products of relatively low temperature processes, stellar winds and cosmic ray reactions - early solar system radiation history. The use of micron-scale primary ion beams will allow detailed sampling of phases within meteorites. Strategies of charge-state selection, molecular disintegration and detection should bring a new set of targets within analytical range. The developing accelerator field is compared to existing (keV energy) ion microprobes

  4. Stable piecewise polynomial vector fields

    Directory of Open Access Journals (Sweden)

    Claudio Pessoa

    2012-09-01

    Full Text Available Let $N={y>0}$ and $S={y<0}$ be the semi-planes of $mathbb{R}^2$ having as common boundary the line $D={y=0}$. Let $X$ and $Y$ be polynomial vector fields defined in $N$ and $S$, respectively, leading to a discontinuous piecewise polynomial vector field $Z=(X,Y$. This work pursues the stability and the transition analysis of solutions of $Z$ between $N$ and $S$, started by Filippov (1988 and Kozlova (1984 and reformulated by Sotomayor-Teixeira (1995 in terms of the regularization method. This method consists in analyzing a one parameter family of continuous vector fields $Z_{epsilon}$, defined by averaging $X$ and $Y$. This family approaches $Z$ when the parameter goes to zero. The results of Sotomayor-Teixeira and Sotomayor-Machado (2002 providing conditions on $(X,Y$ for the regularized vector fields to be structurally stable on planar compact connected regions are extended to discontinuous piecewise polynomial vector fields on $mathbb{R}^2$. Pertinent genericity results for vector fields satisfying the above stability conditions are also extended to the present case. A procedure for the study of discontinuous piecewise vector fields at infinity through a compactification is proposed here.

  5. Stable Structures for Distributed Applications

    Directory of Open Access Journals (Sweden)

    Eugen DUMITRASCU

    2008-01-01

    Full Text Available For distributed applications, we define the linear, tree and graph structure types with different variants and modalities to aggregate them. The distributed applications have assigned structures that through their characteristics influence the costs of stages for developing cycle and the costs for exploitation, transferred to each user. We also present the quality characteristics of a structure for a stable application, which is focused on stability characteristic. For that characteristic we define the estimated measure indicators for a level. The influence of the factors of stability and the ways for increasing it are thus identified, and at the same time the costs of development stages, the costs of usage and the costs of maintenance to be keep on between limits that assure the global efficiency of application. It is presented the base aspects for distributed applications: definition, peculiarities and importance. The aspects for the development cycle of distributed application are detailed. In this article, we alongside give the mechanisms for building the defined structures and analyze the complexity of the defined structures for a distributed application of a virtual store.

  6. Compound-specific radiocarbon analysis - Analytical challenges and applications

    Science.gov (United States)

    Mollenhauer, G.; Rethemeyer, J.

    2009-01-01

    Within the last decades, techniques have become available that allow measurement of isotopic compositions of individual organic compounds (compound-specific isotope measurements). Most often the carbon isotopic composition of these compounds is studied, including stable carbon (δ13C) and radiocarbon (Δ14C) measurements. While compound-specific stable carbon isotope measurements are fairly simple, and well-established techniques are widely available, radiocarbon analysis of specific organic compounds is a more challenging method. Analytical challenges include difficulty obtaining adequate quantities of sample, tedious and complicated laboratory separations, the lack of authentic standards for measuring realistic processing blanks, and large uncertainties in values of Δ14C at small sample sizes. The challenges associated with sample preparation for compound-specific Δ14C measurements will be discussed in this contribution. Several years of compound-specific radiocarbon analysis have revealed that in most natural samples, purified organic compounds consist of heterogeneous mixtures of the same compound. These mixtures could derive from multiple sources, each having a different initial reservoir age but mixed in the same terminal reservoir, from a single source but mixed after deposition, or from a prokaryotic organism using variable carbon sources including mobilization of ancient carbon. These processes not only represent challenges to the interpretation of compound-specific radiocarbon data, but provide unique tools for the understanding of biogeochemical and sedimentological processes influencing the preserved organic geochemical records in marine sediments. We will discuss some examples where compound-specific radiocarbon analysis has provided new insights for the understanding of carbon source utilization and carbon cycling.

  7. Unlock your Compound Management

    OpenAIRE

    Steffen Eller

    2016-01-01

    Pharmaceutical industry faces the increased demand for innovative medicines against various diseases. In this regard, the compound library in pharmaceutical industry is the most valuable asset. However, the compound distribution from the library into the screening plates is often still done manually and binds highly qualified resources to very time-consuming, tedious and error-prone tasks. To overcome these challenges, Chemspeed launched the first automated true one-to-one gravimetric "pi...

  8. physical properties of some noble metal compounds from paw-dft

    African Journals Online (AJOL)

    PUBLICATIONS1

    The heats of formation, shear modulus, fracture toughness, density and melting points of com- ... of the 17 thermodynamically stable compounds are predicted with better hardness. Better frac- .... The hardness of a material has been correlated.

  9. Thiocarbomide coordination compounds of yttrium subgroup rare earth chlorides

    International Nuclear Information System (INIS)

    Sakharova, Yu.G.; Perov, V.N.; Loginov, V.I.

    1978-01-01

    Thiocarbamide coordination compounds of chlorides of elements of the yttrium subgroup 4MeCl 3 x5Cs(NH 2 ) 2 x2OH 2 O (where Me stands for Tb, Dy, Ho, Er, Tm, Yb, Lu, Y) were produced for the first time. The compounds obtained are stable in air, have definite melting points, are highly soluble in methyl and ethyl alcohols, and are unstable in water. They recrystallize from ethyl alcohol without changing their chemical composition. The identity of these compounds was confirmed by X-ray analysis

  10. Phenolic Molding Compounds

    Science.gov (United States)

    Koizumi, Koji; Charles, Ted; de Keyser, Hendrik

    Phenolic Molding Compounds continue to exhibit well balanced properties such as heat resistance, chemical resistance, dimensional stability, and creep resistance. They are widely applied in electrical, appliance, small engine, commutator, and automotive applications. As the focus of the automotive industry is weight reduction for greater fuel efficiency, phenolic molding compounds become appealing alternatives to metals. Current market volumes and trends, formulation components and its impact on properties, and a review of common manufacturing methods are presented. Molding processes as well as unique advanced techniques such as high temperature molding, live sprue, and injection/compression technique provide additional benefits in improving the performance characterisitics of phenolic molding compounds. Of special interest are descriptions of some of the latest innovations in automotive components, such as the phenolic intake manifold and valve block for dual clutch transmissions. The chapter also characterizes the most recent developments in new materials, including long glass phenolic molding compounds and carbon fiber reinforced phenolic molding compounds exhibiting a 10-20-fold increase in Charpy impact strength when compared to short fiber filled materials. The role of fatigue testing and fatigue fracture behavior presents some insight into long-term reliability and durability of glass-filled phenolic molding compounds. A section on new technology outlines the important factors to consider in modeling phenolic parts by finite element analysis and flow simulation.

  11. Identification of a potential superhard compound ReCN

    International Nuclear Information System (INIS)

    Fan, Xiaofeng; Li, M.M.; Singh, David J.; Jiang, Qing; Zheng, W.T.

    2015-01-01

    Highlights: • We identify a new ternary compound ReCN with theoretical calculation. • The ternary compound ReCN is with two stable structures with P63mc and P3m1. • ReCN is a semiconductor from the calculation of electronic structures. • ReCN is found to possess the outstanding mechanical properties. • ReCN may be synthesized relatively easily. - Abstract: We identify a new ternary compound, ReCN and characterize its properties including structural stability and indicators of hardness using first principles calculations. We find that there are two stable structures with space groups P63mc (HI) and P3m1 (HII), in which there are no C–C and N–N bonds. Both structures, H1 and III are elastically and dynamically stable. The electronic structures show that ReCN is a semiconductor, although the parent compounds, ReC 2 and ReN 2 are both metallic. ReCN is found to possess the outstanding mechanical properties with the large bulk modulus, shear modulus and excellent ideal strengths. In addition, ReCN may perhaps be synthesized relatively easily because it becomes thermodynamic stable with respect to decomposition at very low pressures

  12. Chemistry of Stable Carbenes and «Green» Technologies

    Directory of Open Access Journals (Sweden)

    Korotkikh, N.I.

    2015-11-01

    Full Text Available Brief analysis of fundamental research in the chemistry of stable carbenes and applications in the field of «green» chemistry on their basis carried out at the L.M. Litvinenko Institute of Physical Organic & Coal Chemistry of NAS of Ukraine over the last decade is given. Carbene versions of ester Claisen condensation to form zwitterionic compounds, the Leuckart-Wallach reaction with the autoreduction of carbenoid azolium salts, Hofmann cleavage of aminocarbene insertion products, an induced tandem autotransformation of 1,2,4-triazol-5-ylidenes into 5-amidino-1,2,4-triazoles were found. New carbene reactions of ad dition, deesterification, oxidation and complexation were revealed. Effective methods of obtaining stable carbenes and carbenoids were suggested. New types of carbenes, namely benzimidazolylidenes, superstable conjugated biscarbenes and new types of carbenoids were synthesized. The existence of hypernucleophilic carbenes was theoretically predicted and experimentally confirmed. The prospects of the use of carbenes and their derivatives, in particular, carbene complexes of transition metals in catalysis of organic reactions and the search of biologically active compounds were shown.

  13. Coated air-stable cobalt--rare earth alloy particles and method

    International Nuclear Information System (INIS)

    Smeggil, J.C.; Charles, R.J.

    1975-01-01

    A process is described for producing novel air-stable coated particles of a magnetic transition metal-rare earth alloys. An organometallic compound which decomposes at a temperature below 500 0 C is heated to produce a metal vapor which is contacted with particles of a transition metal-rare earth alloy to deposit a metal coating on the particles. (U.S.)

  14. Trends in the use of stable isotopes in biochemistry and pharmacology

    International Nuclear Information System (INIS)

    Matwiyoff, N.A.; Walker, T.E.

    1977-01-01

    Recent trends in the use of the stable isotopes 13 C, 15 N and 18 O in biochemistry and pharmacology are reviewed with emphasis on the studies that have employed nuclear magnetic resonance (nmr) spectroscopy and mass spectrometry as analytical techniques. Pharmacological studies with drugs and other compounds labelled with stable isotopes have developed in parallel with the rapid progress in the enhancement of sensitivity and selectivity of gas chromatography - mass spectrometric analyses, and have been directed largely to an evaluation of pharmako-kinetics and drug metabolic pathways. In these studies, illustrated with selected samples, isotopically labelled compounds have been used to advantage as internal standards for the mass spectrometric analyses and as in vivo tracers for metabolites. In the broader discipline of biochemistry, stable isotopes and isotopically labelled compounds have been used increasingly in conjuction with both nmr spectroscopy and mass spectrometry in tracer and structural studies. The more recent trends in the use of stable isotopes in these biochemical studies are discussed in the context of the improvements in analytical techniques. Specific examples will be drawn from investigations of the biosynthesis of natural products by micro-organisms; the protein, fat and carbohydrate fluxes in humans; and the structure and function of enzymes, membranes and other macro-molecular assemblages. The potential for the future development of stable isotopes in biochemistry and pharmacology are considered briefly, together with some of the problems that must be solved if their considerable potential is to be realized. (author)

  15. Population Games, Stable Games, and Passivity

    Directory of Open Access Journals (Sweden)

    Michael J. Fox

    2013-10-01

    Full Text Available The class of “stable games”, introduced by Hofbauer and Sandholm in 2009, has the attractive property of admitting global convergence to equilibria under many evolutionary dynamics. We show that stable games can be identified as a special case of the feedback-system-theoretic notion of a “passive” dynamical system. Motivated by this observation, we develop a notion of passivity for evolutionary dynamics that complements the definition of the class of stable games. Since interconnections of passive dynamical systems exhibit stable behavior, we can make conclusions about passive evolutionary dynamics coupled with stable games. We show how established evolutionary dynamics qualify as passive dynamical systems. Moreover, we exploit the flexibility of the definition of passive dynamical systems to analyze generalizations of stable games and evolutionary dynamics that include forecasting heuristics as well as certain games with memory.

  16. Stable-isotope analysis: a neglected tool for placing parasites in food webs.

    Science.gov (United States)

    Sabadel, A J M; Stumbo, A D; MacLeod, C D

    2018-02-28

    Parasites are often overlooked in the construction of food webs, despite their ubiquitous presence in almost every type of ecosystem. Researchers who do recognize their importance often struggle to include parasites using classical food-web theory, mainly due to the parasites' multiple hosts and life stages. A novel approach using compound-specific stable-isotope analysis promises to provide considerable insight into the energetic exchanges of parasite and host, which may solve some of the issues inherent in incorporating parasites using a classical approach. Understanding the role of parasites within food webs, and tracing the associated biomass transfers, are crucial to constructing new models that will expand our knowledge of food webs. This mini-review focuses on stable-isotope studies published in the past decade, and introduces compound-specific stable-isotope analysis as a powerful, but underutilized, newly developed tool that may answer many unresolved questions regarding the role of parasites in food webs.

  17. Fluorine-18 labelled compounds

    International Nuclear Information System (INIS)

    Kleijn, J.P. de

    1978-01-01

    The work presented in this thesis deals with the problems involved in the adaption of reactor-produced fluorine-18 to the synthesis of 18 F-labelled organic fluorine compounds. Several 18 F-labelling reagents were prepared and successfully applied. The limitations to the synthetic possibilities of reactor-produced fluoride- 18 become manifest in the last part of the thesis. An application to the synthesis of labelled aliphatic fluoro amino acids has appeared to be unsuccessful as yet, although some other synthetic approaches can be indicated. Seven journal articles (for which see the availability note) are used to compose the four chapters and three appendices. The connecting text gives a survey of known 18 F-compounds and methods for preparing such compounds. (Auth.)

  18. Antibacterial Evaluation of Synthetic Thiazole Compounds In Vitro and In Vivo in a Methicillin-Resistant Staphylococcus aureus (MRSA) Skin Infection Mouse Model.

    Science.gov (United States)

    Mohammad, Haroon; Cushman, Mark; Seleem, Mohamed N

    2015-01-01

    The emergence of community-associated methicillin-resistant Staphylococcus aureus (MRSA), including strains resistant to current antibiotics, has contributed to an increase in the number of skin infections reported in humans in recent years. New therapeutic options are needed to counter this public health challenge. The aim of the present study was to examine the potential of thiazole compounds synthesized by our research group to be used topically to treat MRSA skin and wound infections. The broth microdilution method confirmed that the lead thiazole compound and four analogues are capable of inhibiting MRSA growth at concentrations as low as 1.3 μg/mL. Additionally, three compounds exhibited a synergistic relationship when combined with the topical antibiotic mupirocin against MRSA in vitro via the checkerboard assay. Thus the thiazole compounds have potential to be used alone or in combination with mupirocin against MRSA. When tested against human keratinocytes, four derivatives of the lead compound demonstrated an improved toxicity profile (were found to be non-toxic up to a concentration of 20 μg/mL). Utilizing a murine skin infection model, we confirmed that the lead compound and three analogues exhibited potent antimicrobial activity in vivo, with similar capability as the antibiotic mupirocin, as they reduced the burden of MRSA present in skin wounds by more than 90%. Taken altogether, the present study provides important evidence that these thiazole compounds warrant further investigation for development as novel topical antimicrobials to treat MRSA skin infections.

  19. Chloric organic compound

    International Nuclear Information System (INIS)

    Moalem, F.

    2000-01-01

    Since many years ago, hazardous and toxic refuses which are results of human activities has been carelessly without any Biological and Engineering facts and knowledge discharged into our land and water. The effects of discharging those materials in environment are different. Some of refuse materials shows short and other has long-time adverse effects in our environment, Among hazardous organic chemical materials, chlorine, consider, to be the main element. Organic materials with chlorine is called chlorine hydrocarbon as a hazardous compound. This paper discuss the hazardous materials especially chloric organic compound and their misuse effects in environment and human being

  20. Medicinal gold compounds

    International Nuclear Information System (INIS)

    Parish, R.V.; Cottrill, S.M.

    1987-01-01

    A major use of gold compounds in the pharmaceutical industry is for anti-arthritic agents. The disease itself is not understood and little is known about the way in which the drugs act, but detailed pictures of the distribution of gold in the body are available, and some of the relevant biochemistry is beginning to emerge. The purpose of this article is to give a survey of the types of compounds presently employed in medicine, of the distribution of gold in the body which results from their use, and of some relevant chemistry. Emphasis is placed on results obtained in the last few years

  1. Compound semiconductor device physics

    CERN Document Server

    Tiwari, Sandip

    2013-01-01

    This book provides one of the most rigorous treatments of compound semiconductor device physics yet published. A complete understanding of modern devices requires a working knowledge of low-dimensional physics, the use of statistical methods, and the use of one-, two-, and three-dimensional analytical and numerical analysis techniques. With its systematic and detailed**discussion of these topics, this book is ideal for both the researcher and the student. Although the emphasis of this text is on compound semiconductor devices, many of the principles discussed will also be useful to those inter

  2. Prediction of intermetallic compounds

    International Nuclear Information System (INIS)

    Burkhanov, Gennady S; Kiselyova, N N

    2009-01-01

    The problems of predicting not yet synthesized intermetallic compounds are discussed. It is noted that the use of classical physicochemical analysis in the study of multicomponent metallic systems is faced with the complexity of presenting multidimensional phase diagrams. One way of predicting new intermetallics with specified properties is the use of modern processing technology with application of teaching of image recognition by the computer. The algorithms used most often in these methods are briefly considered and the efficiency of their use for predicting new compounds is demonstrated.

  3. Applications of stable isotopes in clinical pharmacology

    NARCIS (Netherlands)

    Schellekens, Reinout C A; Stellaard, Frans; Woerdenbag, Herman J; Frijlink, Henderik W; Kosterink, Jos G W

    2011-01-01

    This review aims to present an overview of the application of stable isotope technology in clinical pharmacology. Three main categories of stable isotope technology can be distinguished in clinical pharmacology. Firstly, it is applied in the assessment of drug pharmacology to determine the

  4. Stable isotopes and biomarkers in microbial ecology

    NARCIS (Netherlands)

    Boschker, H.T.S.; Middelburg, J.J.

    2002-01-01

    The use of biomarkers in combination with stable isotope analysis is a new approach in microbial ecology and a number of papers on a variety of subjects have appeared. We will first discuss the techniques for analysing stable isotopes in biomarkers, primarily gas chromatography-combustion-isotope

  5. Modelling stable atmospheric boundary layers over snow

    NARCIS (Netherlands)

    Sterk, H.A.M.

    2015-01-01

    Thesis entitled:

    Modelling Stable Atmospheric Boundary Layers over Snow

    H.A.M. Sterk

    Wageningen, 29th of April, 2015

    Summary

    The emphasis of this thesis is on the understanding and forecasting of the Stable Boundary Layer (SBL) over snow-covered surfaces. SBLs

  6. Gas phase thermal diffusion of stable isotopes

    International Nuclear Information System (INIS)

    Eck, C.F.

    1979-01-01

    The separation of stable isotopes at Mound Facility is reviewed from a historical perspective. The historical development of thermal diffusion from a laboratory process to a separation facility that handles all the noble gases is described. In addition, elementary thermal diffusion theory and elementary cascade theory are presented along with a brief review of the uses of stable isotopes

  7. Azaboranes with hydroxypropyl residues as possible new compounds for use in BNCT

    International Nuclear Information System (INIS)

    Bauer, C.; Gabel, D.; Doefler, U.

    2000-01-01

    The azaboranes of the type RNH 2 B 8 H 11 NHR where R contains a hydroxyl group are possible new compounds for BNCT, because they are water stable and more or less water soluble for physiological transport. These compounds also fulfil the condition of not being toxic. (author)

  8. Compound floating pivot micromechanisms

    Science.gov (United States)

    Garcia, Ernest J.

    2001-04-24

    A new class of tilting micromechanical mechanisms have been developed. These new mechanisms use compound floating pivot structures to attain far greater tilt angles than are practical using other micromechanical techniques. The new mechanisms are also capable of bi-directional tilt about multiple axes.

  9. The Onium Compounds

    Science.gov (United States)

    Tsarevsky, Nicolay V.; Slaveykova, Vera; Manev, Stefan; Lazarov, Dobri

    1997-06-01

    The onium salts are of a big interest for theoretical and structural chemistry, and for organic synthesis. Some representatives of the group (e.g. ammonium salts) were known from the oldest times. Many onium salts are met the nature: ammonium salts (either as inorganic salts, and organic derivatives, e.g. aminoacids, salts of biogenic amines and alkaloids, etc.); oxonium salts (plant pigments as anthocyans are organic oxonium compounds), etc. In 1894 C. Hartmann and V. Meyer prepared the first iodonium salts - 4-iododiphenyliodonium hydrogensulfate and diphenyliodonium salts, and suggested the ending -onium for all compounds with properties similar to those of ammonium salts. Nowadays onium compounds of almost all nonmetals are synthesised and studied. A great variety of physical methods: diffraction (e.g. XRD) and spectral methods (IR-, NMR-, and UV-spectra), as well as the chemical properties and methods of preparation of onium salts have been used in determination of the structure of these compounds. The application of different onium salts is immense. Ammonium, phosphonium and sulfonium salts are used as phase-transfer catalysts; diazonium salts - for the preparation of dyes, metalochromic and pH-indicators. All the onium salts and especially diazonium and iodonium salts are very useful reagents in organic synthesis.

  10. Forecasting of superconducting compounds

    International Nuclear Information System (INIS)

    Savitskii, E.M.; Gribulya, V.G.; Kiseleva, N.N.

    1981-01-01

    In forecasting new superconducting intermetallic compounds of the A15 and Mo 3 Se types most promising from the viewpoint of high critical temperature Tsub(c), high critical magnetic fields Hsub(c), and high critical currents and in estimating their transition temperature it is proposed to apply cybernetic methods of computer learning

  11. NATURAL POLYACETYLENE COMPOUNDS

    Directory of Open Access Journals (Sweden)

    A. M. Nasukhova

    2014-01-01

    Full Text Available In article the review of the initial stage of researches of natural polyacetylene compounds is resulted. The high reactionary ability leading to fast oxidation and degradation of these compounds, especially at influence of Uf-light, oxygen of air, pH and other factors, has caused the serious difficulties connected with an establishment of structure and studying of their physical and chemical properties. Therefore the greatest quantity of works of this stage is connected with studying of essential oils of plants from families Apiaceae, Araliaceae, Asteraceae, Campanulaceae, Olacaceae, Pittosporaceae and Santalaceae where have been found out, basically, diacetylene compounds. About development of physical and chemical methods of the analysis of possibility of similar researches have considerably extended. More than 2000 polyacetylenes are known today, from them more than 1100 are found out in plants fam. Asteraceae. Revolution in the field of molecular biology has allowed to study processes of biosynthesis of these compounds intensively.

  12. Aminopropyl thiophene compounds

    International Nuclear Information System (INIS)

    Goodman, M.M.; Knapp, F.F.

    1990-01-01

    This patent describes radiopharmaceuticals useful in brain imaging comprising radiohalogenated thienylethylamine derivatives. The compounds are 5-halo-thiophene-2-isopropyl amines able to cross the blood-brain barrier and be retained for a sufficient length of time to allow the evaluation of regional blood flow by radioimaging of the brain

  13. Aminopropyl thiophene compounds

    Science.gov (United States)

    Goodman, Mark M.; Knapp, Jr., Furn F.

    1990-01-01

    Radiopharmaceuticals useful in brain imaging comprising radiohalogenated thienylethylamine derivatives. The compounds are 5-halo-thiophene-2-isopropyl amines able to cross the blood-brain barrier and be retained for a sufficient length of time to allow the evaluation of regional blood flow by radioimaging of the brain.

  14. Hyperon compound nucleus

    International Nuclear Information System (INIS)

    Yamazaki, Toshimitsu.

    1987-11-01

    The formation of various hypernuclei from K - absorption at rest is discussed from the viewpoints of compound decay of highly excited hypernuclei in contrast to the direct reaction mechanism. Recent (stopped K - , π) experiments at KEK as well as old data of emulsion and bubble chamber experiments are discussed. Some future direction of hypernuclear spectroscopy is suggested. (author)

  15. Chemical compounds in teak

    Directory of Open Access Journals (Sweden)

    Fernanda Viana da Silva Leonardo

    2015-09-01

    Full Text Available Quinone compounds are largely generated at extractive fraction of the woods in a complex and variable biological system. The literature has indications for many segments from food industry to pharmaceutical industry. Within the field of industrial use of wood, they are less desirable since they are treated only as incidental substances in production strings of pulp, paper, charcoal, and sawmill. In spite of its small amount, compared to other chemical compounds called essential, these substances have received special attention from researchers revealing a diverse range of offerings to market products textiles, pharmaceuticals, colorants, and other polymers, for which are being tested and employed. Quinones are found in fungi, lichens, and mostly in higher plants. Tectona grandis, usually called teak, is able to biosynthesize anthraquinones, which is a quinone compound, byproduct of secondary metabolism. This species provides wood that is much prized in the furniture sector and can also be exploited for metabolites to supply the market in quinone compounds and commercial development of new technologies, adding value to the plantations of this species within our country.

  16. Mass spectrometric analysis of stable carbon isotopes in abiogenic and biogenic natural compounds

    International Nuclear Information System (INIS)

    Sajjad, M.I.; Ahmed, M.; Tasneem, M.A.; Khan, I.A.; Latif, Z.

    1989-07-01

    This report describes the general methodology of sup/13/ carbon analysis on mass spectrometer and various preparation systems developed for conversion of samples into isotopically non-fractionated and purified carbon dioxide. Laboratory standards required for sup/13/ C analysis have been calibrated against international standards. The reproducibility/accuracy of sample preparation and analysis on mass spectrometer for sup/13/ C or sup/12/ C measurement is well within the internationally acceptable limits. (author)

  17. Reconstruction of past changes in ocean salinity - a compound specific stable hydrogen isotope approach

    NARCIS (Netherlands)

    Kasper, S.

    2015-01-01

    The extent of the general warming related to increasing anthropogenic CO2 emission andits implications for the global climate system are currently under heavy debate. In particular theextrapolation of long term climatic trends relies on complex climate models for the interactionbetween the

  18. A botanical compound, Padma 28, increases walking distance in stable intermittent claudication

    DEFF Research Database (Denmark)

    Drabaek, H; Mehlsen, J; Himmelstrup, H

    1993-01-01

    and by measurements of the pain-free and the maximal walking distance on a treadmill. The ankle pressure index (ankle systolic pressure/arm systolic pressure) was calculated. The group randomized to active treatment received two tablets bid containing 340 mg of a dried herbal mixture composed according to an ancient...

  19. Tracing carbon flow through coral reef food webs using a compound-specific stable isotope approach

    KAUST Repository

    McMahon, Kelton; Thorrold, Simon R.; Houghton, Leah A.; Berumen, Michael L.

    2015-01-01

    . Seascape configuration played an important role in structuring resource utilization patterns. For instance, Lutjanus ehrenbergii showed a significant shift from a benthic macroalgal food web on shelf reefs (71 ± 13 % of dietary C) to a phytoplankton

  20. Reconstruction of past changes in ocean salinity - a compound specific stable hydrogen isotope approach

    NARCIS (Netherlands)

    Kasper, S.

    2015-01-01

    The extent of the general warming related to increasing anthropogenic CO2 emission and its implications for the global climate system are currently under heavy debate. In particular the extrapolation of long term climatic trends relies on complex climate models for the interaction between the

  1. Lithium Thiophosphate Compounds as Stable High Rate Li-Ion Separators

    Energy Technology Data Exchange (ETDEWEB)

    Apblett, Christopher A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-09-01

    Battery separators based upon lithium thiophosphate (LiPS4) have previously been demonstrated at UC Boulder, but the thickness of the separators was too high to be of practical use in a lithium ion battery. The separators are solid phase, which makes them intrinsically less prone to thermal runaway and thereby improves safety. Results of attempting to develop sputtered thin film layers of this material by starting with targets of pure Li, Li2S, and P2S5 are reported. Sputtering rates and film quality and composition are discussed, along with efforts to use Raman spectroscopy to determine quantitative film composition. The latter is a rate limiting step in the investigation of these films, as they are typically thin and require long times to get to sufficient thickness to be analyzed using traditional methods, whereas Raman is particularly well suited to this analysis, if it can be made quantitative. The final results of the film deposition methods are reported, and a path towards new films is discussed. Finally, it should be noted that this program originally began with one graduate student working on the program, but this student ultimately chose to not continue with a PhD. A second student took over in the middle of the effort, and a new program has been proposed with a significantly altered chemistry to take the program in a new direction.

  2. A botanical compound, Padma 28, increases walking distance in stable intermittent claudication

    DEFF Research Database (Denmark)

    Drabaek, H; Mehlsen, J; Himmelstrup, H

    1993-01-01

    Thirty-six patients with a median age of sixty-seven years and a median duration of intermittent claudication of five years were randomized to either active treatment with Padma 28 or placebo. The effect of treatment was quantified by measurements of systemic and peripheral systolic blood pressur...

  3. Alternative Forms of Compound Fractional Poisson Processes

    Directory of Open Access Journals (Sweden)

    Luisa Beghin

    2012-01-01

    Full Text Available We study here different fractional versions of the compound Poisson process. The fractionality is introduced in the counting process representing the number of jumps as well as in the density of the jumps themselves. The corresponding distributions are obtained explicitly and proved to be solution of fractional equations of order less than one. Only in the final case treated in this paper, where the number of jumps is given by the fractional-difference Poisson process defined in Orsingher and Polito (2012, we have a fractional driving equation, with respect to the time argument, with order greater than one. Moreover, in this case, the compound Poisson process is Markovian and this is also true for the corresponding limiting process. All the processes considered here are proved to be compositions of continuous time random walks with stable processes (or inverse stable subordinators. These subordinating relationships hold, not only in the limit, but also in the finite domain. In some cases the densities satisfy master equations which are the fractional analogues of the well-known Kolmogorov one.

  4. Synthesis of Stable Interfaces on SnO2 Surfaces for Charge-Transfer Applications

    Science.gov (United States)

    Benson, Michelle C.

    The commercial market for solar harvesting devices as an alternative energy source requires them to be both low-cost and efficient to replace or reduce the dependence on fossil fuel burning. Over the last few decades there has been promising efforts towards improving solar devices by using abundant and non-toxic metal oxide nanomaterials. One particular metal oxide of interest has been SnO2 due to its high electron mobility, wide-band gap, and aqueous stability. However SnO2 based solar cells have yet to reach efficiency values of other metal oxides, like TiO2. The advancement of SnO2 based devices is dependent on many factors, including improved methods of surface functionalization that can yield stable interfaces. This work explores the use of a versatile functionalization method through the use of the Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction. The CuAAC reaction is capable of producing electrochemically, photochemically, and electrocatalytically active surfaces on a variety of SnO2 materials. The resulting charge-transfer characteristics were investigated as well as an emphasis on understanding the stability of the resulting molecular linkage. We determined the CuAAC reaction is able to proceed through both azide-modified and alkyne-modified surfaces. The resulting charge-transfer properties showed that the molecular tether was capable of supporting charge separation at the interface. We also investigated the enhancement of electron injection upon the introduction of an ultra-thin ZrO2 coating on SnO2. Several complexes were used to fully understand the charge-transfer capabilities, including model systems of ferrocene and a ruthenium coordination complex, a ruthenium mononuclear water oxidation catalyst, and a commercial ruthenium based dye.

  5. Selenium-75-labelled foliate compounds

    International Nuclear Information System (INIS)

    1974-01-01

    A saturation method to analyze a foliate is presented; it uses competitive reaction of the compound to be measured and of a radioactive-labelled version of this compound with a reagent specific to this compound present in insufficient quantity to combine with the whole of the compound and its labelled version, separation of the bound compound from its non-bound homologue and measurement of the radioactivity concentration in the bound compound, the non-bound compound or both. The radioactive isotope used in the labelled foliate is selenium 75 [fr

  6. Environmental impact by toxic compounds from waste treatment; Miljoepaaverkan fraan toxiska aemnen vid hantering av avfall

    Energy Technology Data Exchange (ETDEWEB)

    Loefblad, Gun; Bisaillon, Mattias; Sundberg, Johan (Profu AB (Sweden))

    2010-07-01

    The study deals with emissions of toxic compounds from waste treatment to the environment with the aim of improving the state of knowledge and to find a way of describing the environmental impact from these substances. Toxicity is one of a number of environmental aspects necessary to address in the planning of waste treatment and in the daily waste treatment routines in order to fulfill the environmental objective A Non-Toxic Environment and other environmental requirements. The study includes waste to incineration, composting and anaerobic digestion. A comparison between methods were made for biological household waste. According to our study, the compounds of importance for waste treatment are metals and persistent organic compounds. These tend to bioaccumulate and enrich in food chains. The substances are important for the environmental objective A Non-Toxic Environment. In a first step the compounds chosen in this study may be suggested for describing toxicity from waste treatment: As, Cd, Cu, Hg, Pb, dioxin, PCB, the phthalate DEHP and the brominated flame retardant HBCDD. Other substances may be added to the list in a next step from up-dated and quality-assured characterisation factors or from other requirements or preferences. There is a limited knowledge on toxic compounds in waste flows and in different environmental compartments. More data are available for metals than for organic substances. There is also a limited knowledge on the fate of the compounds during the waste treatment processes. Most information is found for incineration. During composting and anaerobic digestion the metals will mainly be emitted to the environment by use of the compost and the anaerobic digestion residue. Organic substances will to some extent be degraded during the processes. However, there are gaps of knowledge to fill for the further work on estimating toxic emissions. There is mainly a need for more extensive data on toxic compounds in waste and their variations. A test

  7. Gas chromatographic isolation technique for compound-specific radiocarbon analysis

    International Nuclear Information System (INIS)

    Uchida, M.; Kumamoto, Y.; Shibata, Y.; Yoneda, M.; Morita, M.; Kawamura, K.

    2002-01-01

    Full text: We present here a gas chromatographic isolation technique for the compound-specific radiocarbon analysis of biomarkers from the marine sediments. The biomarkers of fatty acids, hydrocarbon and sterols were isolated with enough amount for radiocarbon analysis using a preparative capillary gas chromatograph (PCGC) system. The PCGC systems used here is composed of an HP 6890 GC with FID, a cooled injection system (CIS, Gerstel, Germany), a zero-dead-volume effluent splitter, and a cryogenic preparative collection device (PFC, Gerstel). For AMS analysis, we need to separate and recover sufficient quantity of target individual compounds (>50 μgC). Yields of target compounds from C 14 n-alkanes to C 40 to C 30 n-alkanes and approximately that of 80% for higher molecular weights compounds more than C 30 n-alkanes. Compound specific radiocarbon analysis of organic compounds, as well as compound-specific stable isotope analysis, provide valuable information on the origins and carbon cycling in marine system. Above PCGC conditions, we applied compound-specific radiocarbon analysis to the marine sediments from western north Pacific, which showed the possibility of a useful chronology tool for estimating the age of sediment using organic matter in paleoceanographic study, in the area where enough amounts of planktonic foraminifera for radiocarbon analysis by accelerator mass spectrometry (AMS) are difficult to obtain due to dissolution of calcium carbonate. (author)

  8. Ballooning stable high beta tokamak equilibria

    International Nuclear Information System (INIS)

    Tuda, Takashi; Azumi, Masafumi; Kurita, Gen-ichi; Takizuka, Tomonori; Takeda, Tatsuoki

    1981-04-01

    The second stable regime of ballooning modes is numerically studied by using the two-dimensional tokamak transport code with the ballooning stability code. Using the simple FCT heating scheme, we find that the plasma can locally enter this second stable regime. And we obtained equilibria with fairly high beta (β -- 23%) stable against ballooning modes in a whole plasma region, by taking into account of finite thermal diffusion due to unstable ballooning modes. These results show that a tokamak fusion reactor can operate in a high beta state, which is economically favourable. (author)

  9. Development of stable isotope manufacturing in Russia

    International Nuclear Information System (INIS)

    Pokidychev, A.; Pokidycheva, M.

    1999-01-01

    For the past 25 years, Russia has relied heavily on the electromagnetic separation process for the production of middle and heavy mass stable isotopes. The separation of most light isotopes had been centered in Georgia which, after the collapse of the USSR, left Russia without this capability. In the mid-1970s, development of centrifuge technology for the separation of stable isotopes was begun. Alternative techniques such as laser separation, physical-chemical methods, and ion cyclotron resonance have also been investigated. Economic considerations have played a major role in the development and current status of the stable isotope enrichment capabilities of Russia

  10. Compound semiconductor device modelling

    CERN Document Server

    Miles, Robert

    1993-01-01

    Compound semiconductor devices form the foundation of solid-state microwave and optoelectronic technologies used in many modern communication systems. In common with their low frequency counterparts, these devices are often represented using equivalent circuit models, but it is often necessary to resort to physical models in order to gain insight into the detailed operation of compound semiconductor devices. Many of the earliest physical models were indeed developed to understand the 'unusual' phenomena which occur at high frequencies. Such was the case with the Gunn and IMPATI diodes, which led to an increased interest in using numerical simulation methods. Contemporary devices often have feature sizes so small that they no longer operate within the familiar traditional framework, and hot electron or even quantum­ mechanical models are required. The need for accurate and efficient models suitable for computer aided design has increased with the demand for a wider range of integrated devices for operation at...

  11. Tripolar Mesoionic Compounds

    OpenAIRE

    Shuki, Araki; Jiro, Mizuya; Naomitsu, Aoyama; Yasuo, Butsugan

    1995-01-01

    Tripolar mesoionic compounds have been synthesized by the reaction of (1,3-diphenyltetrazol-5-ylio)cyclopentadienide (or -indenide) with the dicationic ether salts derived from mesoionic olates and trifluoromethanesulfonic anhydride. The structures of the newly prepared mesoionic systems are discussed on the basis of spectroscopic analysis; it is shown that the tripolar [tetrazolium-cyclopentadienide (or indenide)-tetrazolium] canonical structure contributes significantly to the ground state ...

  12. Oligosilanylated Antimony Compounds

    OpenAIRE

    Zitz, Rainer; Gatterer, Karl; Reinhold, Crispin R. W.; M?ller, Thomas; Baumgartner, Judith; Marschner, Christoph

    2015-01-01

    By reactions of magnesium oligosilanides with SbCl3, a number of oligosilanylated antimony compounds were obtained. When oligosilanyl dianions were used, either the expected cyclic disilylated halostibine was obtained or alternatively the formation of a distibine was observed. Deliberate formation of the distibine from the disilylated halostibine was achieved by reductive coupling with C8K. Computational studies of Sb?Sb bond energies, barriers of pyramidal inversion at Sb, and the conformati...

  13. Process for compound transformation

    KAUST Repository

    Basset, Jean-Marie

    2016-12-29

    Embodiments of the present disclosure provide for methods of using a catalytic system to chemically transform a compound (e.g., a hydrocarbon). In an embodiment, the method does not employ grafting the catalyst prior to catalysis. In particular, embodiments of the present disclosure provide for a process of hydrocarbon (e.g., C1 to C20 hydrocarbon) metathesis (e.g., alkane, olefin, or alkyne metathesis) transformation, where the process can be conducted without employing grafting prior to catalysis.

  14. Compound Semiconductor Radiation Detector

    International Nuclear Information System (INIS)

    Kim, Y. K.; Park, S. H.; Lee, W. G.; Ha, J. H.

    2005-01-01

    In 1945, Van Heerden measured α, β and γ radiations with the cooled AgCl crystal. It was the first radiation measurement using the compound semiconductor detector. Since then the compound semiconductor has been extensively studied as radiation detector. Generally the radiation detector can be divided into the gas detector, the scintillator and the semiconductor detector. The semiconductor detector has good points comparing to other radiation detectors. Since the density of the semiconductor detector is higher than that of the gas detector, the semiconductor detector can be made with the compact size to measure the high energy radiation. In the scintillator, the radiation is measured with the two-step process. That is, the radiation is converted into the photons, which are changed into electrons by a photo-detector, inside the scintillator. However in the semiconductor radiation detector, the radiation is measured only with the one-step process. The electron-hole pairs are generated from the radiation interaction inside the semiconductor detector, and these electrons and charged ions are directly collected to get the signal. The energy resolution of the semiconductor detector is generally better than that of the scintillator. At present, the commonly used semiconductors as the radiation detector are Si and Ge. However, these semiconductor detectors have weak points. That is, one needs thick material to measure the high energy radiation because of the relatively low atomic number of the composite material. In Ge case, the dark current of the detector is large at room temperature because of the small band-gap energy. Recently the compound semiconductor detectors have been extensively studied to overcome these problems. In this paper, we will briefly summarize the recent research topics about the compound semiconductor detector. We will introduce the research activities of our group, too

  15. Bronzes and relative compounds

    International Nuclear Information System (INIS)

    Uehlls, A.

    1987-01-01

    Preparation and the crystal structure of bronzes based on complex oxides of transition (Ti, V, Nb, Ta, Mo, W, Re, Ru and etc.) and alkali metals, as well as oxides of some other elements (Sr, In, La and etc.) are described. Peculiarities of formation of the structure of tetragonal, tungsten, molybdenum, vanadium bronzes and their analogs depending on the chemical composition of these compounds are considered

  16. Compound Wiretap Channels

    Directory of Open Access Journals (Sweden)

    Shlomo Shamai (Shitz

    2009-01-01

    Full Text Available This paper considers the compound wiretap channel, which generalizes Wyner's wiretap model to allow the channels to the (legitimate receiver and to the eavesdropper to take a number of possible states. No matter which states occur, the transmitter guarantees that the receiver decodes its message and that the eavesdropper is kept in full ignorance about the message. The compound wiretap channel can also be viewed as a multicast channel with multiple eavesdroppers, in which the transmitter sends information to all receivers and keeps the information secret from all eavesdroppers. For the discrete memoryless channel, lower and upper bounds on the secrecy capacity are derived. The secrecy capacity is established for the degraded channel and the semideterministic channel with one receiver. The parallel Gaussian channel is further studied. The secrecy capacity and the secrecy degree of freedom (s.d.o.f. are derived for the degraded case with one receiver. Schemes to achieve the s.d.o.f. for the case with two receivers and two eavesdroppers are constructed to demonstrate the necessity of a prefix channel in encoder design. Finally, the multi-antenna (i.e., MIMO compound wiretap channel is studied. The secrecy capacity is established for the degraded case and an achievable s.d.o.f. is given for the general case.

  17. Antifungal compounds from cyanobacteria.

    Science.gov (United States)

    Shishido, Tânia K; Humisto, Anu; Jokela, Jouni; Liu, Liwei; Wahlsten, Matti; Tamrakar, Anisha; Fewer, David P; Permi, Perttu; Andreote, Ana P D; Fiore, Marli F; Sivonen, Kaarina

    2015-04-13

    Cyanobacteria are photosynthetic prokaryotes found in a range of environments. They are infamous for the production of toxins, as well as bioactive compounds, which exhibit anticancer, antimicrobial and protease inhibition activities. Cyanobacteria produce a broad range of antifungals belonging to structural classes, such as peptides, polyketides and alkaloids. Here, we tested cyanobacteria from a wide variety of environments for antifungal activity. The potent antifungal macrolide scytophycin was detected in Anabaena sp. HAN21/1, Anabaena cf. cylindrica PH133, Nostoc sp. HAN11/1 and Scytonema sp. HAN3/2. To our knowledge, this is the first description of Anabaena strains that produce scytophycins. We detected antifungal glycolipopeptide hassallidin production in Anabaena spp. BIR JV1 and HAN7/1 and in Nostoc spp. 6sf Calc and CENA 219. These strains were isolated from brackish and freshwater samples collected in Brazil, the Czech Republic and Finland. In addition, three cyanobacterial strains, Fischerella sp. CENA 298, Scytonema hofmanni PCC 7110 and Nostoc sp. N107.3, produced unidentified antifungal compounds that warrant further characterization. Interestingly, all of the strains shown to produce antifungal compounds in this study belong to Nostocales or Stigonematales cyanobacterial orders.

  18. Toxic compounds in honey.

    Science.gov (United States)

    Islam, Md Nazmul; Khalil, Md Ibrahim; Islam, Md Asiful; Gan, Siew Hua

    2014-07-01

    There is a wealth of information about the nutritional and medicinal properties of honey. However, honey may contain compounds that may lead to toxicity. A compound not naturally present in honey, named 5-hydroxymethylfurfural (HMF), may be formed during the heating or preservation processes of honey. HMF has gained much interest, as it is commonly detected in honey samples, especially samples that have been stored for a long time. HMF is a compound that may be mutagenic, carcinogenic and cytotoxic. It has also been reported that honey can be contaminated with heavy metals such as lead, arsenic, mercury and cadmium. Honey produced from the nectar of Rhododendron ponticum contains alkaloids that can be poisonous to humans, while honey collected from Andromeda flowers contains grayanotoxins, which can cause paralysis of limbs in humans and eventually leads to death. In addition, Melicope ternata and Coriaria arborea from New Zealand produce toxic honey that can be fatal. There are reports that honey is not safe to be consumed when it is collected from Datura plants (from Mexico and Hungary), belladonna flowers and Hyoscamus niger plants (from Hungary), Serjania lethalis (from Brazil), Gelsemium sempervirens (from the American Southwest), Kalmia latifolia, Tripetalia paniculata and Ledum palustre. Although the symptoms of poisoning due to honey consumption may differ depending on the source of toxins, most common symptoms generally include dizziness, nausea, vomiting, convulsions, headache, palpitations or even death. It has been suggested that honey should not be considered a completely safe food. Copyright © 2013 John Wiley & Sons, Ltd.

  19. Antifungal Compounds from Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Tânia K. Shishido

    2015-04-01

    Full Text Available Cyanobacteria are photosynthetic prokaryotes found in a range of environments. They are infamous for the production of toxins, as well as bioactive compounds, which exhibit anticancer, antimicrobial and protease inhibition activities. Cyanobacteria produce a broad range of antifungals belonging to structural classes, such as peptides, polyketides and alkaloids. Here, we tested cyanobacteria from a wide variety of environments for antifungal activity. The potent antifungal macrolide scytophycin was detected in Anabaena sp. HAN21/1, Anabaena cf. cylindrica PH133, Nostoc sp. HAN11/1 and Scytonema sp. HAN3/2. To our knowledge, this is the first description of Anabaena strains that produce scytophycins. We detected antifungal glycolipopeptide hassallidin production in Anabaena spp. BIR JV1 and HAN7/1 and in Nostoc spp. 6sf Calc and CENA 219. These strains were isolated from brackish and freshwater samples collected in Brazil, the Czech Republic and Finland. In addition, three cyanobacterial strains, Fischerella sp. CENA 298, Scytonema hofmanni PCC 7110 and Nostoc sp. N107.3, produced unidentified antifungal compounds that warrant further characterization. Interestingly, all of the strains shown to produce antifungal compounds in this study belong to Nostocales or Stigonematales cyanobacterial orders.

  20. Compound Wiretap Channels

    Directory of Open Access Journals (Sweden)

    Kramer Gerhard

    2009-01-01

    Full Text Available Abstract This paper considers the compound wiretap channel, which generalizes Wyner's wiretap model to allow the channels to the (legitimate receiver and to the eavesdropper to take a number of possible states. No matter which states occur, the transmitter guarantees that the receiver decodes its message and that the eavesdropper is kept in full ignorance about the message. The compound wiretap channel can also be viewed as a multicast channel with multiple eavesdroppers, in which the transmitter sends information to all receivers and keeps the information secret from all eavesdroppers. For the discrete memoryless channel, lower and upper bounds on the secrecy capacity are derived. The secrecy capacity is established for the degraded channel and the semideterministic channel with one receiver. The parallel Gaussian channel is further studied. The secrecy capacity and the secrecy degree of freedom ( are derived for the degraded case with one receiver. Schemes to achieve the for the case with two receivers and two eavesdroppers are constructed to demonstrate the necessity of a prefix channel in encoder design. Finally, the multi-antenna (i.e., MIMO compound wiretap channel is studied. The secrecy capacity is established for the degraded case and an achievable is given for the general case.

  1. Stable Isotope Group 1982 progress report

    International Nuclear Information System (INIS)

    Stewart, M.K.

    1983-06-01

    The work of the Stable Isotope Group of the Institute of Nuclear Sciences during 1982, in the fields of isotope geology, isotope hydrology, geochronology, isotope biology and mass spectrometer instrumentation, is described

  2. Bartolome Island, Galapagos Stable Oxygen Calibration Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Galapagos Coral Stable Oxygen Calibration Data. Sites: Bartolome Island: 0 deg, 17'S, 90 deg 33' W. Champion Island: 1 deg, 15'S, 90 deg, 05' W. Urvina Bay (Isabela...

  3. Stable Isotope Group 1983 progress report

    International Nuclear Information System (INIS)

    Stewart, M.K.

    1984-06-01

    The work of the Stable Isotope Group of the Institute of Nuclear Sciences in the fields of isotope geology, isotope hydrology, geochronology, isotope biology and related fields, and mass spectrometer instrumentation, during 1983, is described

  4. Monitoring of the aerobe biodegradation of chlorinated organic solvents by stable isotope analysis

    Science.gov (United States)

    Horváth, Anikó; Futó, István; Palcsu, László

    2014-05-01

    Our chemical-biological basic research aims to eliminate chlorinated environmental contaminants from aquifers around industrial areas in the frame of research program supported by the European Social Fund (TÁMOP-4.2.2.A-11/1/KONV-2012-0043). The most careful and simplest way includes the in situ biodegradation with the help of cultured and compound specific strains. Numerous members of Pseudomonas bacteria are famous about function of bioremediation. They can metabolism the environmental hazardous chemicals like gas oils, dyes, and organic solvents. Our research based on the Pseudomonas putida F1 strain, because its ability to degrade halogenated hydrocarbons such as trichloroethylene. Several methods were investigated to estimate the rate of biodegradation, such as the measurement of the concentration of the pollutant along the contamination pathway, the microcosm's studies or the compound specific stable isotope analysis. In this area in the Transcarpathian basin we are pioneers in the stable isotope monitoring of biodegradation. The main goal is to find stable isotope fractionation factors by stable isotope analysis, which can help us to estimate the rate and effectiveness of the biodegradation. The subsequent research period includes the investigation of the method, testing its feasibility and adaptation in the environment. Last but not least, the research gives an opportunity to identify the producer of the contaminant based on the stable isotope composition of the contaminant.

  5. Nomenclature on an inorganic compound

    International Nuclear Information System (INIS)

    1998-10-01

    This book contains eleven chapters : which mention nomenclature of an inorganic compound with introduction and general principle on nomenclature of compound. It gives the description of grammar for nomenclature such as brackets, diagonal line, asterisk, and affix, element, atom and groups of atom, chemical formula, naming by stoichiometry, solid, neutral molecule compound, ion, a substituent, radical and name of salt, oxo acid and anion on introduction and definition of oxo acid, coordination compound like symbol of stereochemistry , boron and hydrogen compound and related compound.

  6. Stable atomic hydrogen: Polarized atomic beam source

    International Nuclear Information System (INIS)

    Niinikoski, T.O.; Penttilae, S.; Rieubland, J.M.; Rijllart, A.

    1984-01-01

    We have carried out experiments with stable atomic hydrogen with a view to possible applications in polarized targets or polarized atomic beam sources. Recent results from the stabilization apparatus are described. The first stable atomic hydrogen beam source based on the microwave extraction method (which is being tested ) is presented. The effect of the stabilized hydrogen gas density on the properties of the source is discussed. (orig.)

  7. Special Heusler compounds for spintronic applications

    Energy Technology Data Exchange (ETDEWEB)

    Balke, B.

    2007-07-01

    This work emphasizes the potential of Heusler compounds in a wide range of spintronic applications. Using electronic structure calculations it is possible to design compounds for specific applications. Examples for GMR and TMR applications, for spin injection into semiconductors, and for spin torque transfer applications will be shown. After a detailed introduction about spintronics and related materials chapter 5 reports about the investigation of new half-metallic compounds where the Fermi energy is tuned in the middle of the gap to result in more stable compounds for GMR and TMR applications. The bulk properties of the quaternary Heusler alloy Co{sub 2}Mn{sub 1-x}Fe{sub x}Si with the Fe concentration ranging from x=0 to 1 are reported and the results suggest that the best candidate for applications may be found at an iron concentration of about 50%. Due to the effect that in the Co{sub 2}Mn{sub 1-x}Fe{sub x}Si series the transition metal carrying the localized moment is exchanged and this might lead to unexpected effects on the magnetic properties if the samples are not completely homogeneous chapter 6 reports about the optimization of the Heusler compounds for GMR and TMR applications. The structural and magnetic properties of the quaternary Heusler alloy Co{sub 2}FeAl{sub 1-x}Si{sub x} with varying Si concentration are reported. From the combination of experimental (better order for high Si content) and theoretical findings (robust gap at x=0.5) it is concluded that a compound with an intermediate Si concentration close to x=0.5-0.7 would be best suited for spintronic applications, especially for GMR and TMR applications. In chapter 7 the detailed investigation of compounds for spin injection into semiconductors is reported. It is shown that the diluted magnetic semiconductors based on CoTiSb with a very low lattice mismatch among each other are interesting materials for spintronics applications like Spin-LEDs or other spin injection devices. Chapter 8 refers

  8. Molecular and stable carbon isotopic characterization of PAH contaminants at McMurdo Station, Antarctica

    International Nuclear Information System (INIS)

    Kim, Moonkoo . E-mail moonkoo.kim@wmich.edu; Kennicutt, Mahlon C.; Qian Yaorong

    2006-01-01

    The molecular and stable carbon isotopic compositions of contaminant polycyclic aromatic hydrocarbons (PAHs) at McMurdo Station, Antarctica were analyzed in samples collected from land and sub-tidal area. PAHs in the study areas were characterized by high amounts of naphthalene and alkylated naphthalenes from petroleum products introduced by human activities in the area. Principal component analysis (PCA) of PAH composition data identified multiple sources of PAH contamination in the study area. Compositional assignments of origins were confirmed using compound specific stable carbon isotopic analysis

  9. Development of new technology for the use of stable isotopic tracers in the study of human health and disease

    International Nuclear Information System (INIS)

    Hacyey, D.L.; Klein, P.D.; Szczepanik, P.A.; Niu, W.; Stellaard, F.; Tserng, K.Y.

    1977-01-01

    This program has five major aspects: first, the development of analytical instrumentation of requisite sensitivity, stability, and simplicity to conduct stable isotope measurements in a routine manner; second, the development of appropriately labeled compounds for metabolic investigations, initially through custom syntheses but eventually through commercial sources; third, development of analytical methodology to isolate, purify, and determine the isotopic content of specific organic compounds reflecting metabolic processes or disease states; fourth, collaborative development of clinical applications and testing on a routine basis, through a network of clinical centers around the country; and finally, the collection and dissemination of stable isotope information on an international scale through survey publications and conferences

  10. Offset Compound Gear Drive

    Science.gov (United States)

    Stevens, Mark A.; Handschuh, Robert F.; Lewicki, David G.

    2010-01-01

    The Offset Compound Gear Drive is an in-line, discrete, two-speed device utilizing a special offset compound gear that has both an internal tooth configuration on the input end and external tooth configuration on the output end, thus allowing it to mesh in series, simultaneously, with both a smaller external tooth input gear and a larger internal tooth output gear. This unique geometry and offset axis permits the compound gear to mesh with the smaller diameter input gear and the larger diameter output gear, both of which are on the same central, or primary, centerline. This configuration results in a compact in-line reduction gear set consisting of fewer gears and bearings than a conventional planetary gear train. Switching between the two output ratios is accomplished through a main control clutch and sprag. Power flow to the above is transmitted through concentric power paths. Low-speed operation is accomplished in two meshes. For the purpose of illustrating the low-speed output operation, the following example pitch diameters are given. A 5.0 pitch diameter (PD) input gear to 7.50 PD (internal tooth) intermediate gear (0.667 reduction mesh), and a 7.50 PD (external tooth) intermediate gear to a 10.00 PD output gear (0.750 reduction mesh). Note that it is not required that the intermediate gears on the offset axis be of the same diameter. For this example, the resultant low-speed ratio is 2:1 (output speed = 0.500; product of stage one 0.667 reduction and stage two 0.750 stage reduction). The design is not restricted to the example pitch diameters, or output ratio. From the output gear, power is transmitted through a hollow drive shaft, which, in turn, drives a sprag during which time the main clutch is disengaged.

  11. Local Search Approaches in Stable Matching Problems

    Directory of Open Access Journals (Sweden)

    Toby Walsh

    2013-10-01

    Full Text Available The stable marriage (SM problem has a wide variety of practical applications, ranging from matching resident doctors to hospitals, to matching students to schools or, more generally, to any two-sided market. In the classical formulation, n men and n women express their preferences (via a strict total order over the members of the other sex. Solving an SM problem means finding a stable marriage where stability is an envy-free notion: no man and woman who are not married to each other would both prefer each other to their partners or to being single. We consider both the classical stable marriage problem and one of its useful variations (denoted SMTI (Stable Marriage with Ties and Incomplete lists where the men and women express their preferences in the form of an incomplete preference list with ties over a subset of the members of the other sex. Matchings are permitted only with people who appear in these preference lists, and we try to find a stable matching that marries as many people as possible. Whilst the SM problem is polynomial to solve, the SMTI problem is NP-hard. We propose to tackle both problems via a local search approach, which exploits properties of the problems to reduce the size of the neighborhood and to make local moves efficiently. We empirically evaluate our algorithm for SM problems by measuring its runtime behavior and its ability to sample the lattice of all possible stable marriages. We evaluate our algorithm for SMTI problems in terms of both its runtime behavior and its ability to find a maximum cardinality stable marriage. Experimental results suggest that for SM problems, the number of steps of our algorithm grows only as O(n log(n, and that it samples very well the set of all stable marriages. It is thus a fair and efficient approach to generate stable marriages. Furthermore, our approach for SMTI problems is able to solve large problems, quickly returning stable matchings of large and often optimal size, despite the

  12. Key Aroma Compounds in Lippia dulcis (Dushi Button).

    Science.gov (United States)

    Schmitt, Rainer; Cappi, Michael; Pollner, Gwendola; Greger, Veronika

    2018-03-14

    An aroma extract dilution analysis (AEDA) applied on aroma extracts prepared from the edible flower Dushi Button ( Lippia dulcis) resulted in the detection of 34 odor-active compounds. The highest flavor dilution (FD) factors were determined for methyl 2-methylbutanoate, ethyl 2-methylbutanoate, 4-mercapto-4-methyl-2-pentanone, an unknown caramel-like compound, and vanillin. Quantitative measurements performed by application of stable isotope dilution assays (SIDA), followed by a calculation of odor activity values (OAVs), resulted in the revelation of 4-mercapto-4-methyl-2-pentanone, linalool, myrcene, ethyl 2-methylbutanoate, methyl 2-methylbutanoate, and ( Z)-3-hexenal as important contributors to the flavor of Dushi Buttons.

  13. Application of Stable Isotope in Detection of Veterinary Drug Residues

    International Nuclear Information System (INIS)

    Wang Wei; Liu Zhanfeng; Du Xiaoning

    2010-01-01

    In recent years, there has happened a series of significant food safety events worldwide, which lower down consumers' confidence in food safety, and they are taking increasing care about the sources of their foods. The safety problem of animal-origin foods has become a global topic for discussion. Therefore, it is a pressing task to establish a precise, sensitive and reliable method for analyzing veterinary drug residue. An introduction of the present status regarding veterinary drug residue analysis was made in the paper, and it briefly summarized the limit of detection (LOD) and quantification (LOQ) which could be reached in veterinary drug residue analysis by isotopic internal standard method domestically and abroad. The paper also made a review of the progress in applied research of stable isotope labeled compound in veterinary drug residue analysis of, such as, antibiotic medicines, furans and sulfonamides. The paper elucidated the great importance of the application of stable isotopes in the sane development of China's food safety system. (authors)

  14. Biomedical research applications of electromagnetically separated enriched stable isotopes

    International Nuclear Information System (INIS)

    Lambrecht, R.M.

    1982-01-01

    The current and projected annual requirements through 1985 for stable isotopes enriched by electromagnetic separation methods were reviewed for applications in various types of biomedical research: (1) medical radiosotope production, labeled compounds, and potential radiopharmaceuticals; (2) nutrition, food science, and pharmacology; (3) metallobiochemistry and environmental toxicology; (4) nuclear magnetic resonance, electron paramagnetic resonance, and Moessbauer spectroscopy in biochemical, biophysical, and biomedical research; and (5) miscellaneous advances in radioactive and non-radioactive tracer technology. Radioisotopes available from commercial sources or routinely used in clinical nuclear medicine were excluded. Priorities and summaries are based on statements in the references and from answers to a survey conducted in the fall of 1981. Current requirements for enriched stable isotopes in biomedical research are not being satisfied. Severe shortages exist for 26 Mg, 43 Ca, 70 Zn, 76 Se, 78 Se, 102 Pd, 111 Cd, 113 Cd, and 190 Os. Many interesting and potentially important investigations in biomedical research require small quantities of specific elements at high isotopic enrichments

  15. Toxicology of alkylmercury compounds.

    Science.gov (United States)

    Aschner, Michael; Onishchenko, Natalia; Ceccatelli, Sandra

    2010-01-01

    Methylmercury is a global pollutant and potent neurotoxin whose abundance in the food chain mandates additional studies on the consequences and mechanisms of its toxicity to the central nervous system. Formulation of our new hypotheses was predicated on our appreciation for (a) the remarkable affinity of mercurials for the anionic form of sulfhydryl (-SH) groups, and (b) the essential role of thiols in protein biochemistry. The present chapter addresses pathways to human exposure of various mercury compounds, highlighting their neurotoxicity and potential involvement in neurotoxic injury and neurodegenerative changes, both in the developing and senescent brain. Mechanisms that trigger these effects are discussed in detail.

  16. Compound composite odontoma

    Directory of Open Access Journals (Sweden)

    S Kailasam

    2012-01-01

    Full Text Available Odontomas are the most common type of odontogenic tumors and generally they are asymptomatic. Frequently, it may interfere with the eruption of the teeth. This is a case report of a compound composite odontoma in a 10-year-old girl, which results in failure of eruption of the permanent upper right central incisor while the contralateral tooth had erupted. A calcified mass was seen in the radiograph and was provisionally diagnosed as odontoma following which the odontoma was enucleated. Routine follow-up was done for more than a year and no recurrence was seen. This case report indicates that early diagnosis and management ensures better prognosis.

  17. Flavour Compounds in Fungi

    DEFF Research Database (Denmark)

    Ravasio, Davide Antonio

    . This selection of strains was used in fermentations with the aim of identifying new interesting flavour producers. Fermentation profiles, volatile analyses, off-flavour identification and resistance to osmotic/oxidative stress have been addressed to highlight new candidates to use for industrial applications....... This resulted in the identification of Wickerhamomyces anomalus and Pichia kluyveri as high producers of esters fruity compounds, which contribute to enhance the complexity of wine and beer product. In addition the strain Debaromyces subglobosus showed high yields of aldehydes and fruity ketones, which...

  18. Antifouling Compounds from Marine Invertebrates.

    Science.gov (United States)

    Qi, Shu-Hua; Ma, Xuan

    2017-08-28

    In this review, a comprehensive overview about the antifouling compounds from marine invertebrates is described. In total, more than 198 antifouling compounds have been obtained from marine invertebrates, specifically, sponges, gorgonian and soft corals.

  19. Antifouling Compounds from Marine Invertebrates

    OpenAIRE

    Qi, Shu-Hua; Ma, Xuan

    2017-01-01

    In this review, a comprehensive overview about the antifouling compounds from marine invertebrates is described. In total, more than 198 antifouling compounds have been obtained from marine invertebrates, specifically, sponges, gorgonian and soft corals.

  20. Catalytic properties of niobium compounds

    International Nuclear Information System (INIS)

    Tanabe, K.; Iizuka, T.

    1983-04-01

    The catalytic activity and selectivity of niobium compounds including oxides, salts, organometallic compounds and others are outlined. The application of these compounds as catalysts to diversified reactions is reported. The nature and action of niobium catalysts are characteristic and sometimes anomalous, suggesting the necessity of basic research and the potential use as catalysts for important processes in the chemical industry. (Author) [pt

  1. Molecular modeling of inorganic compounds

    National Research Council Canada - National Science Library

    Comba, Peter; Hambley, Trevor W; Martin, Bodo

    2009-01-01

    ... mechanics to inorganic and coordination compounds. Initially, simple metal complexes were modeled, but recently the field has been extended to include organometallic compounds, catalysis and the interaction of metal ions with biological macromolecules. The application of molecular mechanics to coordination compounds is complicated by the numbe...

  2. Organometallic compounds in the environment

    National Research Council Canada - National Science Library

    Craig, P. J

    2003-01-01

    ... of Organometallic Species in the Environment 20 1.10 Stability of Organometallic Compounds in Biological Systems 1.11 G eneral Comments on the Toxicities of Organometallic Compounds 22 1.12 General Considerations on Environmental R eactivity of Organometallic Compounds 24 1.13 Microbial Biotransformation of Metals and M etalloids 25 1.13.1 Introduction 25 1...

  3. Goldenphilicity: Luminescent gold compounds

    International Nuclear Information System (INIS)

    Sansores, L.E.

    2002-01-01

    In the solids and molecules different types of bonds are presented depending on the involved atoms, covalent bonds are common among elements of open shell, where more bond orbitals are filled than anti bond orbitals. It is expected that ionic bonds among closed shell atoms which have charges of opposite sign. Bonds type Van der Waals are presented among molecules which have a bipolar moment. It would not be expected bonds among zero charge species, or more generally with the same nominal charge and in any case the attractive forces would be very small. In fact it is expected that two metallic cations to be repelled each other. There recently is evidence that in organic or organometallic compounds could exist attractive interactions between two cations of the d 8 -d 10 -s 2 families. These bonds are weak but stronger than those of Van der Waals. They are compared with the hydrogen bonds. In this work it was reviewed some examples in which the goldenphilicity plays an important role in the luminescence that the gold complexes present. Examples of mono, bi and trinuclear and the structures that these organometallic compounds could take are examined. (Author)

  4. Theoretical Study of Some Nitrososulfamide Compounds with Antitumor Activity

    Directory of Open Access Journals (Sweden)

    Madi Fatiha

    2004-09-01

    Full Text Available The lowest-energy conformations of four 2-chloroethylnitrososulfamides were determined using the MM+ molecular mechanics method as implemented in Hyperchem 6.0. Some of the calculated structural parameters, angles and bonds lengths were compared with the crystal structure data of N-nitroso-N-(2-chloroethyl-N’-sulfamoyl- proline. Using MM+, AM1 and PM3 the anti conformation was predicted to be more stable than the syn conformation in each of these compounds. With these methods we found that the relative energy of the transition state (TS was considerably higher, but with the ab initio method using RHF with minimal basic function STO-3G we found that the syn conformation is predicted to be slightly more stable. The determination of some atomic charges of a selection of atoms on the syn, anti and TS structures of the various compounds provided some details about the nature of the transition state.

  5. Difluorothromboxane A2 and stereoisomers: Stable derivatives of thromboxane A2 with differential effects on platelets and blood vessels

    International Nuclear Information System (INIS)

    Morinelli, T.A.; Okwu, A.K.; Mais, D.E.; Halushka, P.V.; John, V.; Chen, Chienkuang; Fried, J.

    1989-01-01

    The present study reports on the selective effects on human platelets and canine saphenous veins of four stable difluorinated analogues and thromboxane A 2 (TXA 2 ), in which the characteristic 2,6-dioxa[3.1.1]bicycloheptane structure of TXA 2 has been retained. The four compounds differ in their stereochemistry of the 5,6 double bond and/or the 15-hydroxyl group. Only 10,10-difluoro-TXA 2 (compound I) with the natural stereochemistry of TXA 2 was an agonist in both platelets and canine saphenous veins. (15R)-10,10-Difluoro-TXA 2 (compound II), (5E)-10,10-difluoro-TXA 2 (compound III), and (5E,15R)-10,10-difluoro-TXA 2 (compound IV) were antagonists of platelet aggregation stimulated by compound I. However, compounds II, III, and IV stimulated contraction of canine saphenous veins. All four compounds could displace the TXA 2 /prostaglandin H 2 antagonist 9,11-dimethylmethano-11,12-methano-16-(3- 125 I-4-hydroxyphenyl)-13,14-dihydro-13-aza-15αβ-ω-tetranor-TXA 2 from its platelet receptor. These results support the existence of two subtypes of TXA 2 /prostaglandin H 2 receptors and emphasize the importance of the stereochemical requirements of these TXA 2 analogues for interaction with these receptors. These stable fluorinated TXA 2 analogues should prove useful tools for the further characterization of these and other TXA 2 /prostaglandin H 2 receptors

  6. Semiconducting III-V compounds

    CERN Document Server

    Hilsum, C; Henisch, Heinz R

    1961-01-01

    Semiconducting III-V Compounds deals with the properties of III-V compounds as a family of semiconducting crystals and relates these compounds to the monatomic semiconductors silicon and germanium. Emphasis is placed on physical processes that are peculiar to III-V compounds, particularly those that combine boron, aluminum, gallium, and indium with phosphorus, arsenic, and antimony (for example, indium antimonide, indium arsenide, gallium antimonide, and gallium arsenide).Comprised of eight chapters, this book begins with an assessment of the crystal structure and binding of III-V compounds, f

  7. Behavior of asphaltene model compounds at w/o interfaces.

    Science.gov (United States)

    Nordgård, Erland L; Sørland, Geir; Sjöblom, Johan

    2010-02-16

    Asphaltenes, present in significant amounts in heavy crude oil, contains subfractions capable of stabilizing water-in-oil emulsions. Still, the composition of these subfractions is not known in detail, and the actual mechanism behind emulsion stability is dependent on perceived interfacial concentrations and compositions. This study aims at utilizing polyaromatic surfactants which contains an acidic moiety as model compounds for the surface-active subfraction of asphaltenes. A modified pulse-field gradient (PFG) NMR method has been used to study droplet sizes and stability of emulsions prepared with asphaltene model compounds. The method has been compared to the standard microscopy droplet counting method. Arithmetic and volumetric mean droplet sizes as a function of surfactant concentration and water content clearly showed that the interfacial area was dependent on the available surfactant at the emulsion interface. Adsorption of the model compounds onto hydrophilic silica has been investigated by UV depletion, and minor differences in the chemical structure of the model compounds caused significant differences in the affinity toward this highly polar surface. The cross-sectional areas obtained have been compared to areas from the surface-to-volume ratio found by NMR and gave similar results for one of the two model compounds. The mean molecular area for this compound suggested a tilted geometry of the aromatic core with respect to the interface, which has also been proposed for real asphaltenic samples. The film behavior was further investigated using a liquid-liquid Langmuir trough supporting the ability to form stable interfacial films. This study supports that acidic, or strong hydrogen-bonding fractions, can promote stable water-in-oil emulsion. The use of model compounds opens up for studying emulsion behavior and demulsifier efficiency based on true interfacial concentrations rather than perceived interfaces.

  8. Compound-specific effects of diverse neurodevelopmental toxicants on global gene expression in the neural embryonic stem cell test (ESTn)

    International Nuclear Information System (INIS)

    Theunissen, P.T.; Robinson, J.F.; Pennings, J.L.A.; Herwijnen, M.H. van; Kleinjans, J.C.S.; Piersma, A.H.

    2012-01-01

    Alternative assays for developmental toxicity testing are needed to reduce animal use in regulatory toxicology. The in vitro murine neural embryonic stem cell test (ESTn) was designed as an alternative for neurodevelopmental toxicity testing. The integration of toxicogenomic-based approaches may further increase predictivity as well as provide insight into underlying mechanisms of developmental toxicity. In the present study, we investigated concentration-dependent effects of six mechanistically diverse compounds, acetaldehyde (ACE), carbamazepine (CBZ), flusilazole (FLU), monoethylhexyl phthalate (MEHP), penicillin G (PENG) and phenytoin (PHE), on the transcriptome and neural differentiation in the ESTn. All compounds with the exception of PENG altered ESTn morphology (cytotoxicity and neural differentiation) in a concentration-dependent manner. Compound induced gene expression changes and corresponding enriched gene ontology biological processes (GO–BP) were identified after 24 h exposure at equipotent differentiation-inhibiting concentrations of the compounds. Both compound-specific and common gene expression changes were observed between subsets of tested compounds, in terms of significance, magnitude of regulation and functionality. For example, ACE, CBZ and FLU induced robust changes in number of significantly altered genes (≥ 687 genes) as well as a variety of GO–BP, as compared to MEHP, PHE and PENG (≤ 55 genes with no significant changes in GO–BP observed). Genes associated with developmentally related processes (embryonic morphogenesis, neuron differentiation, and Wnt signaling) showed diverse regulation after exposure to ACE, CBZ and FLU. In addition, gene expression and GO–BP enrichment showed concentration dependence, allowing discrimination of non-toxic versus toxic concentrations on the basis of transcriptomics. This information may be used to define adaptive versus toxic responses at the transcriptome level.

  9. Antiviral effect of compounds derived from the seeds of Mammea americana and Tabernaemontana cymosa on Dengue and Chikungunya virus infections.

    Science.gov (United States)

    Gómez-Calderón, Cecilia; Mesa-Castro, Carol; Robledo, Sara; Gómez, Sergio; Bolivar-Avila, Santiago; Diaz-Castillo, Fredyc; Martínez-Gutierrez, Marlen

    2017-01-18

    The transmission of Dengue virus (DENV) and Chikungunya virus (CHIKV) has increased worldwide, due in part to the lack of a specific antiviral treatment. For this reason, the search for compounds with antiviral potential, either as licensed drugs or in natural products, is a research priority. The objective of this study was to identify some of the compounds that are present in Mammea americana (M. americana) and Tabernaemontana cymosa (T. cymosa) plants and, subsequently, to evaluate their cytotoxicity in VERO cells and their potential antiviral effects on DENV and CHIKV infections in those same cells. Dry ethanolic extracts of M. americana and T. cymosa seeds were subjected to open column chromatographic fractionation, leading to the identification of four compounds: two coumarins, derived from M. americana; and lupeol acetate and voacangine derived from T. cymosa.. The cytotoxicity of each compound was subsequently assessed by the MTT method (at concentrations from 400 to 6.25 μg/mL). Pre- and post-treatment antiviral assays were performed at non-toxic concentrations; the resulting DENV inhibition was evaluated by Real-Time PCR, and the CHIKV inhibition was tested by the plating method. The results were analyzed by means of statistical analysis. The compounds showed low toxicity at concentrations ≤ 200 μg/mL. The compounds coumarin A and coumarin B, which are derived from the M. americana plant, significantly inhibited infection with both viruses during the implementation of the two experimental strategies employed here (post-treatment with inhibition percentages greater than 50%, p treatment with percentages of inhibition greater than 40%, p treatment strategy (at inhibition percentages greater than 70%, p treating Dengue and Chikungunya fever. Additionally, lupeol acetate and voacangine efficiently inhibit infection with DENV, also turning them into promising antivirals for Dengue fever.

  10. Compound-specific effects of diverse neurodevelopmental toxicants on global gene expression in the neural embryonic stem cell test (ESTn)

    Energy Technology Data Exchange (ETDEWEB)

    Theunissen, P.T., E-mail: Peter.Theunissen@rivm.nl [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Department of Toxicogenomics, Maastricht University, Maastricht (Netherlands); Robinson, J.F. [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Department of Toxicogenomics, Maastricht University, Maastricht (Netherlands); Netherlands Toxicogenomics Centre, Maastricht (Netherlands); Pennings, J.L.A. [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Netherlands Toxicogenomics Centre, Maastricht (Netherlands); Herwijnen, M.H. van [Department of Toxicogenomics, Maastricht University, Maastricht (Netherlands); Kleinjans, J.C.S. [Department of Toxicogenomics, Maastricht University, Maastricht (Netherlands); Netherlands Toxicogenomics Centre, Maastricht (Netherlands); Piersma, A.H. [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Netherlands Toxicogenomics Centre, Maastricht (Netherlands); Institute for Risk Assessment Sciences, Faculty of Veterinary Sciences, Utrecht University, Utrecht (Netherlands)

    2012-08-01

    Alternative assays for developmental toxicity testing are needed to reduce animal use in regulatory toxicology. The in vitro murine neural embryonic stem cell test (ESTn) was designed as an alternative for neurodevelopmental toxicity testing. The integration of toxicogenomic-based approaches may further increase predictivity as well as provide insight into underlying mechanisms of developmental toxicity. In the present study, we investigated concentration-dependent effects of six mechanistically diverse compounds, acetaldehyde (ACE), carbamazepine (CBZ), flusilazole (FLU), monoethylhexyl phthalate (MEHP), penicillin G (PENG) and phenytoin (PHE), on the transcriptome and neural differentiation in the ESTn. All compounds with the exception of PENG altered ESTn morphology (cytotoxicity and neural differentiation) in a concentration-dependent manner. Compound induced gene expression changes and corresponding enriched gene ontology biological processes (GO–BP) were identified after 24 h exposure at equipotent differentiation-inhibiting concentrations of the compounds. Both compound-specific and common gene expression changes were observed between subsets of tested compounds, in terms of significance, magnitude of regulation and functionality. For example, ACE, CBZ and FLU induced robust changes in number of significantly altered genes (≥ 687 genes) as well as a variety of GO–BP, as compared to MEHP, PHE and PENG (≤ 55 genes with no significant changes in GO–BP observed). Genes associated with developmentally related processes (embryonic morphogenesis, neuron differentiation, and Wnt signaling) showed diverse regulation after exposure to ACE, CBZ and FLU. In addition, gene expression and GO–BP enrichment showed concentration dependence, allowing discrimination of non-toxic versus toxic concentrations on the basis of transcriptomics. This information may be used to define adaptive versus toxic responses at the transcriptome level.

  11. Perspective: Highly stable vapor-deposited glasses

    Science.gov (United States)

    Ediger, M. D.

    2017-12-01

    This article describes recent progress in understanding highly stable glasses prepared by physical vapor deposition and provides perspective on further research directions for the field. For a given molecule, vapor-deposited glasses can have higher density and lower enthalpy than any glass that can be prepared by the more traditional route of cooling a liquid, and such glasses also exhibit greatly enhanced kinetic stability. Because vapor-deposited glasses can approach the bottom of the amorphous part of the potential energy landscape, they provide insights into the properties expected for the "ideal glass." Connections between vapor-deposited glasses, liquid-cooled glasses, and deeply supercooled liquids are explored. The generality of stable glass formation for organic molecules is discussed along with the prospects for stable glasses of other types of materials.

  12. Concentration of stable elements in food products

    International Nuclear Information System (INIS)

    Montford, M.A.; Shank, K.E.; Hendricks, C.; Oakes, T.W.

    1980-01-01

    Food samples were taken from commercial markets and analyzed for stable element content. The concentrations of most stable elements (Ag, Al, As, Au, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Cu, Fe, Hf, I, K, La, Mg, Mn, Mo, Na, Rb, Sb, Sc, Se, Sr, Ta, Th, Ti, V, Zn, Zr) were determined using multiple-element neutron activation analysis, while the concentrations of other elements (Cd, Hg, Ni, Pb) were determined using atomic absorption. The relevance of the concentrations found are noted in relation to other literature values. An earlier study was extended to include the determination of the concentration of stable elements in home-grown products in the vicinity of the Oak Ridge National Laboratory. Comparisons between the commercial and local food-stuff values are discussed

  13. Stable Chimeras and Independently Synchronizable Clusters

    Science.gov (United States)

    Cho, Young Sul; Nishikawa, Takashi; Motter, Adilson E.

    2017-08-01

    Cluster synchronization is a phenomenon in which a network self-organizes into a pattern of synchronized sets. It has been shown that diverse patterns of stable cluster synchronization can be captured by symmetries of the network. Here, we establish a theoretical basis to divide an arbitrary pattern of symmetry clusters into independently synchronizable cluster sets, in which the synchronization stability of the individual clusters in each set is decoupled from that in all the other sets. Using this framework, we suggest a new approach to find permanently stable chimera states by capturing two or more symmetry clusters—at least one stable and one unstable—that compose the entire fully symmetric network.

  14. On some topological properties of stable measures

    DEFF Research Database (Denmark)

    Nielsen, Carsten Krabbe

    1996-01-01

    Summary The paper shows that the set of stable probability measures and the set of Rational Beliefs relative to a given stationary measure are closed in the strong topology, but not closed in the topology of weak convergence. However, subsets of the set of stable probability measures which...... are characterized by uniformity of convergence of the empirical distribution are closed in the topology of weak convergence. It is demonstrated that such subsets exist. In particular, there is an increasing sequence of sets of SIDS measures who's union is the set of all SIDS measures generated by a particular...... system and such that each subset consists of stable measures. The uniformity requirement has a natural interpretation in terms of plausibility of Rational Beliefs...

  15. Volatile organic compounds

    International Nuclear Information System (INIS)

    Silseth, May Liss

    1998-01-01

    The goal is: Not more emission of volatile organic compounds (VOCs) than necessary. The items discussed in this presentation are the VOCs, how to calculate emission of VOCs, how to reduce or avoid them, and different recovery processes. The largest source of Norwegian emissions of non methane VOCs (NMVOCs) is offshore loading of raw petroleum. Emissions of VOCs should be reduced mainly for two reasons: (1) on sunny days NMVOCs may react with NOx to form ozon and smog close to the surface, (2) ozone and smog close to the surface may be harmful to plants and animals, and they are hazardous to human health. As for the calculation of VOC emissions, the VOCON project will release the calculation program HCGASS in 1999. This project is a cooperative project headed by SINTEF/Marintek

  16. Synthesis of labeled compounds

    International Nuclear Information System (INIS)

    Whaley, T.W.

    1977-01-01

    Intermediate compounds labeled with 13 C included methane, sodium cyanide, methanol, ethanol, and acetonitrile. A new method for synthesizing 15 N-labeled 4-ethylsulfonyl-1-naphthalene-sulfonamide was developed. Studies were conducted on pathways to oleic-1- 13 C acid and a second pathway investigated was based on carbonation of 8-heptadecynylmagnesium bromide with CO 2 to prepare sterolic acid. Biosynthetic preparations included glucose- 13 C from starch isolated from tobacco leaves following photosynthetic incubation with 13 CO 2 and galactose- 13 C from galactosylglycerol- 13 C from kelp. Research on growth of organisms emphasized photosynthetic growth of algae in which all cellular carbon is labeled. Preliminary experiments were performed to optimize the growth of Escherichia coli on sodium acetate- 13 C

  17. Deposition of acidifying compounds

    International Nuclear Information System (INIS)

    Fowler, D.; Cape, J.N.; Sutton, M.A.; Mourne, R.; Hargreaves, K.J.; Duyzer, J.H.; Gallagher, M.W.

    1992-01-01

    Inputs of acidifying compounds to terrestrial ecosystems include deposition of the gases NO 2 , NO, HNO 2 , HNO 3 , NH 3 and SO 2 and the ions NO 3- , NH 4+ , SO 4 2- and H + in precipitation, cloud droplets and particles. Recent research has identified particular ecosystems and regions in which terrestrial effects are closely linked with specific deposition processes. This review paper identifies areas in which important developments have occurred during the last five years and attempts to show which aspects of the subject are most important for policy makers. Amongst the conclusions drawn, the authors advise that current uncertainties in estimates of S and N inputs by dry deposition should be incorporated in critical load calculations, and that, in regions dominated by wet deposition, spatial resolution of total inputs should be improved to match the current scales of information on landscape sensitivity to acidic inputs. 44 refs., 9 figs

  18. The synthesis of tritium, carbon-14 and stable isotope labelled selective estrogen receptor degraders.

    Science.gov (United States)

    Bragg, Ryan A; Bushby, Nick; Ericsson, Cecilia; Kingston, Lee P; Ji, Hailong; Elmore, Charles S

    2016-09-01

    As part of a Medicinal Chemistry program aimed at developing an orally bioavailable selective estrogen receptor degrader, a number of tritium, carbon-14, and stable isotope labelled (E)-3-[4-(2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indol-1-yl)phenyl]prop-2-enoic acids were required. This paper discusses 5 synthetic approaches to this compound class. Copyright © 2016 John Wiley & Sons, Ltd.

  19. Development of advanced, non-toxic, synthetic radiation shielding aggregate

    Energy Technology Data Exchange (ETDEWEB)

    Mudgal, Manish; Chouhan, Ramesh Kumar; Verma, Sarika; Amritphale, Sudhir Sitaram; Das, Satyabrata [CSIR-Advanced Materials and Processes Research Institute, Bhopal (India); Shrivastva, Arvind [Nuclear Power Corporation of India Ltd. (NPCIL), Mumbai (India)

    2018-04-01

    For the first time in the world, the capability of red mud waste has been explored for the development of advanced synthetic radiation shielding aggregate. Red mud, an aluminium industry waste consists of multi component, multi elemental characteristics. In this study, red mud from two different sources have been utilized. Chemical formulation and mineralogical designing of the red mud has been done by ceramic processing using appropriate reducing agent and additives. The chemical analysis, SEM microphotographs and XRD analysis confirms the presence of multi-component, multi shielding and multi-layered phases in both the different developed advance synthetic radiation shielding aggregate. The mechanical properties, namely aggregate impact value, aggregate crushing value and aggregate abrasion value have also been evaluated and was compared with hematite ore aggregate and found to be an excellent material useful for making advanced radiation shielding concrete for the construction of nuclear power plants and other radiation installations.

  20. Functional Genomics of a Non-Toxic Alexandrium Lusitanicum Culture

    Science.gov (United States)

    2007-02-01

    cultured in the Laboratorio de Micro- minutum analyzed with the same methods and instrument biologia e Ecotoxicologia where the loss of toxicity was...and Lach.) dies., Gonyaulax tamarensis Leb., and Peridinium trochoideum (Stein) Lemm. Notas e Estudos do Instituto de Biologia Marinha 26: 1-21. Silva

  1. Why are Functional Amyloids Non-Toxic in Humans?

    Directory of Open Access Journals (Sweden)

    Matthew P. Jackson

    2017-09-01

    Full Text Available Amyloids were first identified in association with amyloidoses, human diseases in which proteins and peptides misfold into amyloid fibrils. Subsequent studies have identified an array of functional amyloid fibrils that perform physiological roles in humans. Given the potential for the production of toxic species in amyloid assembly reactions, it is remarkable that cells can produce these functional amyloids without suffering any obvious ill effect. Although the precise mechanisms are unclear, there are a number of ways in which amyloid toxicity may be prevented. These include regulating the level of the amyloidogenic peptides and proteins, minimising the production of prefibrillar oligomers in amyloid assembly reactions, sequestrating amyloids within membrane bound organelles, controlling amyloid assembly by other molecules, and disassembling the fibrils under physiological conditions. Crucially, a better understanding of how toxicity is avoided in the production of functional amyloids may provide insights into the prevention of amyloid toxicity in amyloidoses.

  2. Non-Toxic, Self-Cleaning Silicone Fouling Release Coatings

    National Research Council Canada - National Science Library

    Cella, James

    1997-01-01

    ... have been identified for preparation of gel wall microencapsulations. A carbinol terminated PDMS and two ablative oils were synthesized for use in the compositions downselected for panel preparation for subcontractor sites...

  3. Functional Genomics of a Non-Toxic Alexandrium Lusitanicum Culture

    National Research Council Canada - National Science Library

    Martins, Claudia A

    2007-01-01

    .... The loss of toxicity was accompanied by a reduction in growth capability. A subculture of this isolate maintains the ability to produce toxins and to grow at rates and to cell abundances that were characteristic of the original Alexandrium culture...

  4. Evaluation of genetic diversity between toxic and non toxic Jatropha ...

    African Journals Online (AJOL)

    Strategies for breeding improved varieties could be accelerated by DNA-based molecular marker technology. Wild Mexican accessions and accessions from other parts of the world (South America and Africa) were analyzed by 40 simple sequence repeat (SSR) markers. SSR primers were chosen on the grounds of their Tm ...

  5. Non-toxic invert analog glass compositions of high modulus

    Science.gov (United States)

    Bacon, J. F. (Inventor)

    1974-01-01

    Glass compositions having a Young's modulus of at least 15 million psi are described. They and a specific modulus of at least 110 million inches consist essentially of, in mols, 15 to 40% SiO2, 6 to 15% Li2O, 24 to 45% of at least two bivalent oxides selected from the group consisting of Ca, NzO, MgO and CuO; 13 to 39% of at least two trivalent oxides selected from the group consisting of Al2O3, Fe2O3, B2O3, La2O3, and Y2O3 and up to 15% of one or more tetravelent oxides selected from the group consisting of ZrO2, TiO2 and CeO2. The high modulus, low density glass compositions contain no toxic elements. The composition, glass density, Young's modulus, and specific modulus for 28 representative glasses are presented. The fiber modulus of five glasses are given.

  6. Radioiodine therapy in non-toxic multinodular goitre

    DEFF Research Database (Denmark)

    Bonnema, Steen J; Nielsen, Viveque E; Hegedüs, Laszlo

    2006-01-01

    I activity, rhTSH pre-stimulation improves the goitre reduction by 30-50%. However, this is at the expense of a higher rate of hypothyroidism, cervical pain and transient thyrotoxicosis. Of particular concern is the observation made in healthy persons, that rhTSH results in a transient average...

  7. Faster and Simpler Approximation of Stable Matchings

    Directory of Open Access Journals (Sweden)

    Katarzyna Paluch

    2014-04-01

    Full Text Available We give a 3 2 -approximation algorithm for finding stable matchings that runs in O(m time. The previous most well-known algorithm, by McDermid, has the same approximation ratio but runs in O(n3/2m time, where n denotes the number of people andm is the total length of the preference lists in a given instance. In addition, the algorithm and the analysis are much simpler. We also give the extension of the algorithm for computing stable many-to-many matchings.

  8. Moving stable solitons in Galileon theory

    International Nuclear Information System (INIS)

    Masoumi, Ali; Xiao Xiao

    2012-01-01

    Despite the no-go theorem Endlich et al. (2011) which rules out static stable solitons in Galileon theory, we propose a family of solitons that evade the theorem by traveling at the speed of light. These domain-wall-like solitons are stable under small fluctuations-analysis of perturbation shows neither ghost-like nor tachyon-like instabilities, and perturbative collision of these solitons suggests that they pass through each other asymptotically, which maybe an indication of the integrability of the theory itself.

  9. Bordism, stable homotopy and adams spectral sequences

    CERN Document Server

    Kochman, Stanley O

    1996-01-01

    This book is a compilation of lecture notes that were prepared for the graduate course "Adams Spectral Sequences and Stable Homotopy Theory" given at The Fields Institute during the fall of 1995. The aim of this volume is to prepare students with a knowledge of elementary algebraic topology to study recent developments in stable homotopy theory, such as the nilpotence and periodicity theorems. Suitable as a text for an intermediate course in algebraic topology, this book provides a direct exposition of the basic concepts of bordism, characteristic classes, Adams spectral sequences, Brown-Peter

  10. Stable isotopes in Lithuanian bioarcheological material

    Science.gov (United States)

    Skipityte, Raminta; Jankauskas, Rimantas; Remeikis, Vidmantas

    2015-04-01

    Investigation of bioarcheological material of ancient human populations allows us to understand the subsistence behavior associated with various adaptations to the environment. Feeding habits are essential to the survival and growth of ancient populations. Stable isotope analysis is accepted tool in paleodiet (Schutkowski et al, 1999) and paleoenvironmental (Zernitskaya et al, 2014) studies. However, stable isotopes can be useful not only in investigating human feeding habits but also in describing social and cultural structure of the past populations (Le Huray and Schutkowski, 2005). Only few stable isotope investigations have been performed before in Lithuanian region suggesting a quite uniform diet between males and females and protein intake from freshwater fish and animal protein. Previously, stable isotope analysis has only been used to study a Stone Age population however, more recently studies have been conducted on Iron Age and Late medieval samples (Jacobs et al, 2009). Anyway, there was a need for more precise examination. Stable isotope analysis were performed on human bone collagen and apatite samples in this study. Data represented various ages (from 5-7th cent. to 18th cent.). Stable carbon and nitrogen isotope analysis on medieval populations indicated that individuals in studied sites in Lithuania were almost exclusively consuming C3 plants, C3 fed terrestrial animals, and some freshwater resources. Current investigation demonstrated social differences between elites and country people and is promising in paleodietary and daily life reconstruction. Acknowledgement I thank prof. dr. G. Grupe, Director of the Anthropological and Palaeoanatomical State Collection in Munich for providing the opportunity to work in her laboratory. The part of this work was funded by DAAD. Antanaitis-Jacobs, Indre, et al. "Diet in early Lithuanian prehistory and the new stable isotope evidence." Archaeologia Baltica 12 (2009): 12-30. Le Huray, Jonathan D., and Holger

  11. Unconditionally stable microwave Si-IMPATT amplifiers

    International Nuclear Information System (INIS)

    Seddik, M.M.

    1986-07-01

    The purpose of this investigation has been the development of an improved understanding of the design and analysis of microwave reflection amplifiers employing the negative resistance property of the IMPATT devices. Unconditionally stable amplifier circuit using a Silicon IMPATT diode is designed. The problems associated with the design procedures and the stability criterion are discussed. A computer program is developed to perform the computations. The stable characteristics of a reflection-type Si-IMPATT amplifier, such as gain, frequency and bandwidth are examined. It was found that at large signal drive levels, 7 dB gain with bandwidth of 800 MHz at 22,5 mA was obtained. (author)

  12. [Synthesis and characterization of chromium doped Y3Al5O12 compound pigment].

    Science.gov (United States)

    Yue, Shi-Juan; Su, Xiao; Jiang, Han-Jie; Liu, Shao-Xuan; Hong, You-Li; Zhang, Kai; Huang, Wan-Xias; Xiong, Zu-Jiang; Zhao, Ying; Liu, Cui-Ge; Wei, Yong-Ju; Meng, Tao; Xu, Yi-Zhuang; Wu, Jin-Guang

    2012-09-01

    The authors synthesized a new kind of green pigment via co-precipitation method by doping Y3Al5O12 with Cr+. The size of the pigment particles is around 200 nm as observed under scanning electron microscope. XRD results demonstrate that the pigment crystalline form of the pigment is yttrium alluminium garnet. UV-Vis spectra were used to investigate the coordination states and transition behavior of the doping ions. In addition, the colour feature was measured by CIE L* a* b* chroma value. The pigment was blended with polypropylene and then polypropylene fiber was produced using the polypropelene-pigment composite via molten spinning process. The distribution of the pigment particles in the polypropylene fibers was characterized by Xray computed tomography (CT) technique on the Beijing synchrotron radiation facility. The result states that the composite oxide pigment particles are homogeneously dispersed in the polypropylene fibers. The pigments are stable, non-toxic to the environment, and may be applied in non-aqueous dyeing to reduce waste water emitted by textile dyeing and printing industry.

  13. petrography, compositional characteristics and stable isotope ...

    African Journals Online (AJOL)

    PROF EKWUEME

    Subsurface samples of the predominantly carbonate Ewekoro Formation, obtained from Ibese core hole within the Dahomey basin were used in this study. Investigations entail petrographic, elemental composition as well as stable isotopes (carbon and oxygen) geochemistry in order to deduce the different microfacies and ...

  14. Working conditions remain stable in the Netherlands

    NARCIS (Netherlands)

    Houtman, I.; Hooftman, W.

    2008-01-01

    Despite significant changes in the national questionnaires on work and health, the quality of work as well as health complaints in the Netherlands appear to be relatively stable. Pace of work seems to be on the increase again and more people are working in excess of their contractual hours.

  15. Thermally stable sintered porous metal articles

    International Nuclear Information System (INIS)

    Gombach, A.L.; Thellmann, E.L.

    1980-01-01

    A sintered porous metal article is provided which is essentially thermally stable at elevated temperatures. In addition, a method for producing such an article is also provided which method comprises preparing a blend of base metal particles and active dispersoid particles, forming the mixture into an article of the desired shape, and heating the so-formed article at sintering temperatures

  16. TOF for heavy stable particle identification

    International Nuclear Information System (INIS)

    Chang, C.Y.

    1983-01-01

    Searching for heavy stable particle production in a new energy region of hadron-hadron collisions is of fundamental theoretical interest. Observation of such particles produced in high energy collisions would indicate the existence of stable heavy leptons or any massive hadronic system carrying new quantum numbers. Experimentally, evidence of its production has not been found for PP collisions either at FNAL or at the CERN ISR for √S = 23 and 62 GeV respectively. However, many theories beyond the standard model do predict its existence on a mass scale ranging from 50 to a few hundred GeV. If so, it would make a high luminosity TeV collider an extremely ideal hunting ground for searching the production of such a speculated object. To measure the mass of a heavy stable charged particle, one usually uses its time of flight (TOF) and/or dE/dX information. For heavy neutral particle, one hopes it may decay at some later time after its production. Hence a pair of jets or a jet associated with a high P/sub t/ muon originated from some places other than the interacting point (IP) of the colliding beams may be a good signal. In this note, we examine the feasibility of TOF measurement on a heavy stable particle produced in PP collisions at √S = 1 TeV and a luminosity of 10 33 cm -2 sec -1 with a single arm spectrometer pointing to the IP

  17. Axisymmetric MHD stable sloshing ion distributions

    International Nuclear Information System (INIS)

    Berk, H.L.; Dominguez, N.; Roslyakov, G.V.

    1986-07-01

    The MHD stability of a sloshing ion distribution is investigated in a symmetric mirror cell. Fokker-Planck calculations show that stable configurations are possible for ion injection energies that are at least 150 times greater than the electron temperture. Special axial magnetic field profiles are suggested to optimize the favorable MHD properties

  18. Exact simulation of max-stable processes.

    Science.gov (United States)

    Dombry, Clément; Engelke, Sebastian; Oesting, Marco

    2016-06-01

    Max-stable processes play an important role as models for spatial extreme events. Their complex structure as the pointwise maximum over an infinite number of random functions makes their simulation difficult. Algorithms based on finite approximations are often inexact and computationally inefficient. We present a new algorithm for exact simulation of a max-stable process at a finite number of locations. It relies on the idea of simulating only the extremal functions, that is, those functions in the construction of a max-stable process that effectively contribute to the pointwise maximum. We further generalize the algorithm by Dieker & Mikosch (2015) for Brown-Resnick processes and use it for exact simulation via the spectral measure. We study the complexity of both algorithms, prove that our new approach via extremal functions is always more efficient, and provide closed-form expressions for their implementation that cover most popular models for max-stable processes and multivariate extreme value distributions. For simulation on dense grids, an adaptive design of the extremal function algorithm is proposed.

  19. Unconditionally stable integration of Maxwell's equations

    NARCIS (Netherlands)

    Verwer, J.G.; Bochev, Mikhail A.

    Numerical integration of Maxwell's equations is often based on explicit methods accepting a stability step size restriction. In literature evidence is given that there is also a need for unconditionally stable methods, as exemplified by the successful alternating direction implicit finite difference

  20. Unconditionally stable integration of Maxwell's equations

    NARCIS (Netherlands)

    J.G. Verwer (Jan); M.A. Botchev

    2008-01-01

    htmlabstractNumerical integration of Maxwell''s equations is often based on explicit methods accepting a stability step size restriction. In literature evidence is given that there is also a need for unconditionally stable methods, as exemplified by the successful alternating direction

  1. Unconditionally stable integration of Maxwell's equations

    NARCIS (Netherlands)

    J.G. Verwer (Jan); M.A. Botchev

    2009-01-01

    textabstractNumerical integration of Maxwell’s equations is often based on explicit methods accepting a stability step size restriction. In literature evidence is given that there is also a need for unconditionally stable methods, as exemplified by the successful alternating direction implicit –

  2. Method of producing thermally stable uranium carbonitrides

    International Nuclear Information System (INIS)

    Ugajin, M.; Takahashi, I.

    1975-01-01

    A thermally stable uranium carbonitride can be produced by adding tungsten and/or molybdenum in the amount of 0.2 wt percent or more, preferably 0.5 wt percent or more, to a pure uranium carbonitride. (U.S.)

  3. Champion Island, Galapagos Stable Oxygen Calibration Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Galapagos Coral Stable Oxygen Calibration Data. Sites: Bartolome Island: 0 deg, 17 min S, 90 deg 33 min W. Champion Island: 1 deg, 15 min S, 90 deg, 05 min W. Urvina...

  4. 26 S proteasomes function as stable entities

    DEFF Research Database (Denmark)

    Hendil, Klavs B; Hartmann-Petersen, Rasmus; Tanaka, Keiji

    2002-01-01

    , shuttles between a free state and the 26-S proteasome, bringing substrate to the complex. However, S5a was not found in the free state in HeLa cells. Besides, all subunits in PA700, including S5a, exchanged at similar low rates. It therefore seems that 26-S proteasomes function as stable entities during...

  5. Formal derivation of a stable marriage algorithm.

    NARCIS (Netherlands)

    Bijlsma, A.

    1991-01-01

    In this paper the well-known Stable Marriage Problem is considered once again. The name of this programming problem comes from the terms in which it was first described [2]: A certain community consists of n men and n women. Each person ranks those of the opposite sex in accordance with his or

  6. In vitro and in vivo activity of an organic tellurium compound on Leishmania (Leishmania chagasi.

    Directory of Open Access Journals (Sweden)

    Isabella Aparecida Salerno Pimentel

    Full Text Available Tellurium compounds have shown several biological properties and recently the leishmanicidal effect of one organotellurane was demonstrated. These findings led us to test the effect of the organotellurium compound RF07 on Leishmania (Leishmania chagasi, the agent of visceral leishmaniasis in Latin America. In vitro assays were performed in L. (L. chagasi-infected bone marrow derived macrophages treated with different concentrations of RF07. In in vivo experiments Golden hamsters were infected with L. (L. chagasi and injected intraperitoneally with RF07 whereas control animals received either Glucantime or PBS. The effect of RF07 on cathepsin B activity of L. (L. chagasi amastigotes was assayed spectrofluorometrically using fluorogenic substrates. The main findings were: 1 RF07 showed significant leishmanicidal activity against intracellular parasites at submicromolar concentrations (IC50 of 529.7±26.5 nM, and the drug displayed 10-fold less toxicity to macrophages (CC50 of 5,426±272.8 nM; 2 kinetics assays showed an increasing leishmanicidal action of RF07 at longer periods of treatment; 3 one month after intraperitoneal injection of RF07 L. (L. chagasi-infected hamsters showed a reduction of 99.6% of parasite burden when compared to controls that received PBS; 4 RF07 inhibited the cathepsin B activity of L. (L. chagasi amastigotes. The present results demonstrated that the tellurium compound RF07 is able to destroy L. (L. chagasi in vitro and in vivo at concentrations that are non toxic to the host. We believe these findings support further study of the potential of RF07 as a possible alternative for the chemotherapy of visceral leishmaniasis.

  7. Gas Phase Thz Spectroscopy of Organosulfide and Organophosphorous Compounds Using a Synchrotron Source

    Science.gov (United States)

    Cuisset, Arnaud; Smirnova, Irina; Bocquet, Robin; Hindle, Francis; Mouret, Gael; Sadovskii, Dmitrii A.; Pirali, Olivier; Roy, Pascale

    2011-06-01

    This study concerns the gas phase rovibrational spectroscopy of organosulfide and organophosphorous which are considered as non toxic model compounds in the analysis of chemical weapon materials, high pathogenic and mutagenic agents, and other environmentally interesting air-borne species. The coupling of the synchrotron radiation with multipass cells and the FTIR spectrometer allowed to obtain very conclusive results in term of sensitivity and resolution and improved the previous results obtained with classical sources. For DMSO, using an optical path of 150 m the spectra have been recorded at the ultimate resolution of 0.001 Cm-1 allowing to fully resolve the rotational structure of the lowest vibrational modes observed in the THz region. In the 290 - 420 Cm-1 region, the rovibrational spectrum of the "perpendicular" and "parallel" vibrational bands associated with, respectively, the asymmetric ν23 and symmetric ν11 bending modes of DMSO have been recorded with a resolution of 1.5× 10-3 Cm-1. The gas phase vibrational spectra of organophosphorous compounds were measured by FTIR spectroscopy using the vapor pressure of the compounds. Except for TBP, the room temperature vapor pressure was sufficient to detect all active vibrational modes from THz to NIR domain. Contrary to DMSO, the rotational patterns of alkyl phosphates and alkyl phosphonates could not be resolved; only a vibrational analysis may be performed. Nevertheless, the spectral fingerprints observed in the THz region allowed a clear discrimination between the molecules and between the different molecular conformations. A. Cuisset, G. Mouret, O. Pirali, P. Roy, F. Cazier, H. Nouali, J. Demaison, J. Phys. Chem. B, 2008, 112:, 12516-12525 A. Cuisset, L. Nanobashvili, I. Smirnova, R. Bocquet, F. Hindle, G. Mouret, O. Pirali, P. Roy and D. A. Sadovskií, Chem. Phys. Lett., 2010, 492: 30-34 I. Smirnova, A. Cuisset, R. Bocquet, F. Hindle, G. Mouret, O. Pirali, P. Roy, J. Phys. Chem. B, 2010, 114: 16936-16947.

  8. The Nature of Stable Insomnia Phenotypes

    Science.gov (United States)

    Pillai, Vivek; Roth, Thomas; Drake, Christopher L.

    2015-01-01

    Study Objectives: We examined the 1-y stability of four insomnia symptom profiles: sleep onset insomnia; sleep maintenance insomnia; combined onset and maintenance insomnia; and neither criterion (i.e., insomnia cases that do not meet quantitative thresholds for onset or maintenance problems). Insomnia cases that exhibited the same symptom profile over a 1-y period were considered to be phenotypes, and were compared in terms of clinical and demographic characteristics. Design: Longitudinal. Setting: Urban, community-based. Participants: Nine hundred fifty-four adults with Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition based current insomnia (46.6 ± 12.6 y; 69.4% female). Interventions: None. Measurements and results: At baseline, participants were divided into four symptom profile groups based on quantitative criteria. Follow-up assessment 1 y later revealed that approximately 60% of participants retained the same symptom profile, and were hence judged to be phenotypes. Stability varied significantly by phenotype, such that sleep onset insomnia (SOI) was the least stable (42%), whereas combined insomnia (CI) was the most stable (69%). Baseline symptom groups (cross-sectionally defined) differed significantly across various clinical indices, including daytime impairment, depression, and anxiety. Importantly, however, a comparison of stable phenotypes (longitudinally defined) did not reveal any differences in impairment or comorbid psychopathology. Another interesting finding was that whereas all other insomnia phenotypes showed evidence of an elevated wake drive both at night and during the day, the “neither criterion” phenotype did not; this latter phenotype exhibited significantly higher daytime sleepiness despite subthreshold onset and maintenance difficulties. Conclusions: By adopting a stringent, stability-based definition, this study offers timely and important data on the longitudinal trajectory of specific insomnia phenotypes. With

  9. Strontium stable isotope behaviour accompanying basalt weathering

    Science.gov (United States)

    Burton, K. W.; Parkinson, I. J.; Gíslason, S. G. R.

    2016-12-01

    The strontium (Sr) stable isotope composition of rivers is strongly controlled by the balance of carbonate to silicate weathering (Krabbenhöft et al. 2010; Pearce et al. 2015). However, rivers draining silicate catchments possess distinctly heavier Sr stable isotope values than their bedrock compositions, pointing to significant fractionation during weathering. Some have argued for preferential release of heavy Sr from primary phases during chemical weathering, others for the formation of secondary weathering minerals that incorporate light isotopes. This study presents high-precision double-spike Sr stable isotope data for soils, rivers, ground waters and estuarine waters from Iceland, reflecting both natural weathering and societal impacts on those environments. The bedrock in Iceland is dominantly basaltic, d88/86Sr ≈ +0.27, extending to lighter values for rhyolites. Geothermal waters range from basaltic Sr stable compositions to those akin to seawater. Soil pore waters reflect a balance of input from primary mineral weathering, precipitation and litter recycling and removal into secondary phases and vegetation. Rivers and ground waters possess a wide range of d88/86Sr compositions from +0.101 to +0.858. Elemental and isotope data indicate that this fractionation primarily results from the formation or dissolution of secondary zeolite (d88/86Sr ≈ +0.10), but also carbonate (d88/86Sr ≈ +0.22) and sometimes anhydrite (d88/86Sr ≈ -0.73), driving the residual waters to heavier or lighter values, respectively. Estuarine waters largely reflect mixing with seawater, but are also be affected by adsorption onto particulates, again driving water to heavy values. Overall, these data indicate that the stability and nature of secondary weathering phases, exerts a strong control on the Sr stable isotope composition of silicate rivers. [1] Krabbenhöft et al. (2010) Geochim. Cosmochim. Acta 74, 4097-4109. [2] Pearce et al. (2015) Geochim. Cosmochim. Acta 157, 125-146.

  10. Thermodynamic behavior of glassy state of structurally related compounds.

    Science.gov (United States)

    Kaushal, Aditya Mohan; Bansal, Arvind Kumar

    2008-08-01

    Thermodynamic properties of amorphous pharmaceutical forms are responsible for enhanced solubility as well as poor physical stability. The present study was designed to investigate the differences in thermodynamic parameters arising out of disparate molecular structures and associations for four structurally related pharmaceutical compounds--celecoxib, valdecoxib, rofecoxib, and etoricoxib. Conventional and modulated temperature differential scanning calorimetry were employed to study glass forming ability and thermodynamic behavior of the glassy state of model compounds. Glass transition temperature of four glassy compounds was in a close range of 327.6-331.8 K, however, other thermodynamic parameters varied considerably. Kauzmann temperature, strength parameter and fragility parameter showed rofecoxib glass to be most fragile of the four compounds. Glass forming ability of the compounds fared similar in the critical cooling rate experiments, suggesting that different factors were determining the glass forming ability and subsequent behavior of the compounds in glassy state. A comprehensive understanding of such thermodynamic facets of amorphous form would help in rationalizing the approaches towards development of stable glassy pharmaceuticals.

  11. One-pot radioiodination of aryl amines via stable diazonium salts: preparation of 125I-imaging agents

    OpenAIRE

    Sloan, Nikki L.; Luthra, Sajinder K.; McRobbie, Graeme; Pimlott, Sally L.; Sutherland, Andrew

    2017-01-01

    An operationally simple, one-pot, two-step tandem procedure that allows the incorporation of radioactive iodine into aryl amines via stable diazonium salts is described. The mild conditions are tolerant of various functional groups and substitution patterns, allowing late-stage, rapid access to a wide range of 125I-labelled aryl compounds and SPECT radiotracers.

  12. A one-pot radioiodination of aryl amines via stable diazonium salts: preparation of 125I-imaging agents.

    Science.gov (United States)

    Sloan, Nikki L; Luthra, Sajinder K; McRobbie, Graeme; Pimlott, Sally L; Sutherland, Andrew

    2017-10-05

    An operationally simple, one-pot, two-step tandem procedure that allows the incorporation of radioactive iodine into aryl amines via stable diazonium salts is described. The mild conditions are tolerant of various functional groups and substitution patterns, allowing late-stage, rapid access to a wide range of 125 I-labelled aryl compounds and SPECT radiotracers.

  13. Trophodynamics and functional feeding groups of North Sea fauna: a combined stable isotope and fatty acid approach

    NARCIS (Netherlands)

    Kürten, B.; Frutos, I.; Struck, U.; Painting, S.J.; Polunin, N.V.C.; Middelburg, J.J.

    The trophodynamics of pelagic and benthic animals of the North Sea, North Atlantic shelf, were assessed using stable isotope analysis (SIA) of natural abundance carbon and nitrogen isotopes, lipid fingerprinting and compound-specific SIA (CSIA) of phospholipid-derived fatty acids (PLFAs).

  14. Trophodynamics and functional feeding groups of North Sea fauna: a combined stable isotope and fatty acid approach

    NARCIS (Netherlands)

    Kürten, B.; Frutos, I.; Struck, U.; Painting, S.J.; Polunin, N.V.C.; Middelburg, J.J.

    2013-01-01

    The trophodynamics of pelagic and benthic animals of the North Sea, North Atlantic shelf, were assessed using stable isotope analysis (SIA) of natural abundance carbon and nitrogen isotopes, lipid fingerprinting and compound-specific SIA (CSIA) of phospholipid-derived fatty acids (PLFAs).

  15. TSTA compound cryopump

    International Nuclear Information System (INIS)

    Batzer, T.H.; Patrick, R.E.; Call, W.R.

    1980-01-01

    The Tritium System Test Assembly (TSTA), at the Los Alamos Scientific Laboratory, is intended to demonstrate realistic fuel supply and cleanup scenarios for future fusion reactors. The vacuum pumps must be capable of handling large quantities of reactor exhaust gases consisting largely of mixtures of hydrogen and helium isotopes. Cryocondensing pumps will not pump helium at 4.2 K; while cryosorption pumps using molecular sieves or charcoal have good helium pumping speed, the adsorbent clogs with condensed hydrogen while pumping mixtures of both. A solution to this problem is a compound design whereby the first stage condenses the hydrogen and the second, or sorption, stage pumps the helium. The TSTA pump designed at Lawrence Livermore National Laboratory uses argon gas to cryotrap the helium in the helium-hydrogen mixture. The argon is sprayed directly onto the 4.2 K surface at a rate proportional to the helium flow rate, permitting continuous pumping of the helium-hydrogen mixtures in a single-stage pump. However, the possibility of differential desorption as a first stage in the TSTA gas separation cycle required the inclusion of a first-stage hydrogen isotope condenser. The design, performance, and operating characteristics are discussed

  16. Pluto's Nonvolatile Chemical Compounds

    Science.gov (United States)

    Grundy, William M.; Binzel, Richard; Cook, Jason C.; Cruikshank, Dale P.; Dalle Ore, Cristina M.; Earle, Alissa M.; Ennico, Kimberly; Jennings, Donald; Howett, Carly; Kaiser, Ralf-Ingo; Linscott, Ivan; Lunsford, A. W.; Olkin, Catherine B.; Parker, Alex Harrison; Parker, Joel Wm.; Philippe, Sylvain; Protopapa, Silvia; Quirico, Eric; Reuter, D. C.; Schmitt, Bernard; Singer, Kelsi N.; Spencer, John R.; Stansberry, John A.; Stern, S. Alan; Tsang, Constantine; Verbiscer, Anne J.; Weaver, Harold A.; Weigle, G. E.; Young, Leslie

    2016-10-01

    Despite the migration of Pluto's volatile ices (N2, CO, and CH4) around the surface on seasonal timescales, the planet's non-volatile materials are not completely hidden from view. They occur in a variety of provinces formed over a wide range of timescales, including rugged mountains and chasms, the floors of mid-latitude craters, and an equatorial belt of especially dark and reddish material typified by the informally named Cthulhu Regio. NASA's New Horizons probe observed several of these regions at spatial resolutions as fine as 3 km/pixel with its LEISA imaging spectrometer, covering wavelengths from 1.25 to 2.5 microns. Various compounds that are much lighter than the tholin-like macromolecules responsible for the reddish coloration, but that are not volatile at Pluto surface temperatures such as methanol (CH3OH) and ethane (C2H6) have characteristic absorption bands within LEISA's wavelength range. This presentation will describe their geographic distributions and attempt to constrain their origins. Possibilities include an inheritance from Pluto's primordial composition (the likely source of H2O ice seen on Pluto's surface) or ongoing production from volatile precursors through photochemistry in Pluto's atmosphere or through radiolysis on Pluto's surface. New laboratory data inform the analysis.This work was supported by NASA's New Horizons project.

  17. Affixation and compounding in Hakka

    OpenAIRE

    Ungsitipoonporn, Siriopen

    2014-01-01

    This paper aims to present the internal structures of words in the Hakka language. Similar to other languages, affixation and compounding are outstanding in Hakka. In general, prefixes and suffixes are bound morphemes which do not occur independently, but in Hakka they sometimes appear as independent forms. Apart from single words, identifying compound words is of particular interest. Compound nouns can be made up of two or three words (characters) which ...

  18. Development of a Safety Management Web Tool for Horse Stables.

    Science.gov (United States)

    Leppälä, Jarkko; Kolstrup, Christina Lunner; Pinzke, Stefan; Rautiainen, Risto; Saastamoinen, Markku; Särkijärvi, Susanna

    2015-11-12

    Managing a horse stable involves risks, which can have serious consequences for the stable, employees, clients, visitors and horses. Existing industrial or farm production risk management tools are not directly applicable to horse stables and they need to be adapted for use by managers of different types of stables. As a part of the InnoEquine project, an innovative web tool, InnoHorse, was developed to support horse stable managers in business, safety, pasture and manure management. A literature review, empirical horse stable case studies, expert panel workshops and stakeholder interviews were carried out to support the design. The InnoHorse web tool includes a safety section containing a horse stable safety map, stable safety checklists, and examples of good practices in stable safety, horse handling and rescue planning. This new horse stable safety management tool can also help in organizing work processes in horse stables in general.

  19. Stable isotope-guided analysis of biomagnification profiles of arsenic species in a tropical mangrove ecosystem

    International Nuclear Information System (INIS)

    Tu, Nguyen Phuc Cam; Agusa, Tetsuro; Ha, Nguyen Ngoc; Tuyen, Bui Cach; Tanabe, Shinsuke; Takeuchi, Ichiro

    2011-01-01

    We performed stable carbon and nitrogen-guided analyses of biomagnification profiles of arsenic (As) species, including total As, lipid-soluble As, eight water-soluble As compounds (arsenobetaine (AB), arsenocholine (AC), tetramethylarsonium ion (TETRA), trimethylarsine oxide (TMAO), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA), arsenate (As[V]), and arsenite (As[III])), and non-extracted As in a tropical mangrove ecosystem in the Ba Ria Vung Tau, South Vietnam. Arsenobetaine was the predominant As species (65-96% of water-soluble As). Simple linear regression slopes of log-transformed concentrations of total As, As fractions or individual As compounds on stable nitrogen isotopic ratio (δ 15 N) values are regarded as indices of biomagnification. In this ecosystem, lipid-soluble As (slope, 0.130) and AB (slope, 0.108) were significantly biomagnified through the food web; total As and other water-soluble As compounds were not. To our knowledge, this is one of the first reports on biomagnification profiles of As compounds from a tropical mangrove ecosystem.

  20. Natural compounds with herbicidal activity

    Directory of Open Access Journals (Sweden)

    Mariano Fracchiolla

    2007-12-01

    Full Text Available Research about phytotoxic activity of natural compounds could lead both to find new herbicidal active ingredients and to plan environmental friendly weed control strategies. Particularly, living organisms could be a source of compounds that are impossible, for their complexity, to synthesize artificially. More over, they could have alternative sites of action respect to the known chemical herbicides and, due to their origin, they should be more environmental safe. Many living organism, such as bacteria, fungi, insects, lichens and plants, are able to produce bioactive compounds. They generally are secondary metabolites or simply waste molecules. In this paper we make a review about these compounds, highlighting potential and constraints.

  1. Natural compounds with herbicidal activity

    Directory of Open Access Journals (Sweden)

    Pasquale Montemurro

    2011-02-01

    Full Text Available Research about phytotoxic activity of natural compounds could lead both to find new herbicidal active ingredients and to plan environmental friendly weed control strategies. Particularly, living organisms could be a source of compounds that are impossible, for their complexity, to synthesize artificially. More over, they could have alternative sites of action respect to the known chemical herbicides and, due to their origin, they should be more environmental safe. Many living organism, such as bacteria, fungi, insects, lichens and plants, are able to produce bioactive compounds. They generally are secondary metabolites or simply waste molecules. In this paper we make a review about these compounds, highlighting potential and constraints.

  2. Measurement of loss rates of organic compounds in snow using in situ experiments and isotopically labelled compounds

    Directory of Open Access Journals (Sweden)

    Erika von Schneidemesser

    2012-07-01

    Full Text Available Organic molecular marker compounds are widely used to identify emissions from anthropogenic and biogenic air pollution sources in atmospheric samples and in deposition. Specific organic compounds have been detected in polar regions, but their fate after deposition to snow is poorly characterized. Within this context, a series of exposure experiments were carried out to observe the post-depositional processing of organic compounds under real-world conditions in snow on the surface of the Greenland Ice Sheet, at the Summit research station. Snow was prepared from water spiked with isotopically labelled organic compounds, representative of typical molecular marker compounds emitted from anthropogenic activities. Reaction rate constants and reaction order were determined based on a decrease in concentration to a stable, non-zero, threshold concentration. Fluoranthene-d10, docosane-d46, hexadecanoic acid-d31, docosanoic acid-d43 and azelaic acid-d14 were estimated to have first order loss rates within surface snow with reaction rate constants of 0.068, 0.040, 0.070, 0.067 and 0.047 h−1, respectively. No loss of heptadecane-d36 was observed. Overall, these results suggest that organic contaminants are archived in polar snow, although significant post-depositional losses of specific organic compounds occur. This has implications for the environmental fate of organic contaminants, as well as for ice-core studies that seek to use organic molecular markers to infer past atmospheric loadings, and source emissions.

  3. Compounded Apixaban Suspensions for Enteral Feeding Tubes.

    Science.gov (United States)

    Caraballo, Maria L; Donmez, Seda; Nathan, Kobi; Zhao, Fang

    2017-07-01

    Objective: There is limited information on compounded apixaban formulations for administration via enteral feeding tubes. This study was designed to identify a suitable apixaban suspension formulation that is easy to prepare in a pharmacy setting, is compatible with commonly used feeding tubes, and has a beyond-use date of 7 days. Methods: Apixaban suspensions were prepared from commercially available 5-mg Eliquis tablets. Several vehicles and compounding methods were screened for ease of preparation, dosage accuracy, and tube compatibility. Two tubing types, polyurethane and polyvinyl chloride, with varying lengths and diameters, were included in the study. They were mounted on a peg board during evaluation to mimic the patient body position. A 7-day stability study of the selected formulation was also conducted. Results: Vehicles containing 40% to 60% Ora-Plus in water all exhibited satisfactory flowability through the tubes. The mortar/pestle compounding method was found to produce more accurate and consistent apixaban suspensions than the pill crusher or crushing syringe method. The selected formulation, 0.25 mg/mL apixaban in 50:50 Ora-Plus:water, was compatible with both tubing types, retaining >98% drug in posttube samples. The stability study also confirmed that this formulation was stable physically and chemically over 7 days of storage at room temperature. Conclusions: A suitable apixaban suspension formulation was identified for administration via enteral feeding tubes. The formulation consisted of 0.25 mg/mL apixaban in 50:50 Ora-Plus:water. The stability study results supported a beyond-use date of 7 days at room temperature.

  4. Anti-TNF-α Activity of Brazilian Medicinal Plants and Compounds from Ouratea semiserrata.

    Science.gov (United States)

    Campana, Priscilla R V; Mansur, Daniel S; Gusman, Grasielle S; Ferreira, Daneel; Teixeira, Mauro M; Braga, Fernão C

    2015-10-01

    Several plant species are used in Brazil to treat inflammatory diseases and associated conditions. TNF-α plays a pivotal role on inflammation, and several plant extracts have been assayed against this target, both in vitro and in vivo. The effect of 11 Brazilian medicinal plants on TNF-α release by LPS-activated THP-1 cells was evaluated. The plant materials were percolated with different solvents to afford 15 crude extracts, whose effect on TNF-α release was determined by ELISA. Among the evaluated extracts, only Jacaranda caroba (Bignoniaceae) presented strong toxicity to THP-1 cells. Considering the 14 non-toxic extracts, TNF-α release was significantly reduced by seven of them (inhibition > 80%), originating from six plants, namely Cuphea carthagenensis (Lythraceae), Echinodorus grandiflorus (Alismataceae), Mansoa hirsuta (Bignoniaceae), Ouratea semiserrata (Ochnaceae), Ouratea spectabilis and Remijia ferruginea (Rubiaceae). The ethanol extract from O. semiserrata leaves was fractionated over Sephadex LH-20 and RP-HPLC to give three compounds previously reported for the species, along with agathisflavone and epicatechin, here described for the first time in the plant. Epicatechin and lanceoloside A elicited significant inhibition of TNF-α release, indicating that they may account for the effect produced by O. semiserrata crude extract. Copyright © 2015 John Wiley & Sons, Ltd.

  5. Antimicrobial compounds in tears.

    Science.gov (United States)

    McDermott, Alison M

    2013-12-01

    The tear film coats the cornea and conjunctiva and serves several important functions. It provides lubrication, prevents drying of the ocular surface epithelia, helps provide a smooth surface for refracting light, supplies oxygen and is an important component of the innate defense system of the eye providing protection against a range of potential pathogens. This review describes both classic antimicrobial compounds found in tears such as lysozyme and some more recently identified such as members of the cationic antimicrobial peptide family and surfactant protein-D as well as potential new candidate molecules that may contribute to antimicrobial protection. As is readily evident from the literature review herein, tears, like all mucosal fluids, contain a plethora of molecules with known antimicrobial effects. That all of these are active in vivo is debatable as many are present in low concentrations, may be influenced by other tear components such as the ionic environment, and antimicrobial action may be only one of several activities ascribed to the molecule. However, there are many studies showing synergistic/additive interactions between several of the tear antimicrobials and it is highly likely that cooperativity between molecules is the primary way tears are able to afford significant antimicrobial protection to the ocular surface in vivo. In addition to effects on pathogen growth and survival some tear components prevent epithelial cell invasion and promote the epithelial expression of innate defense molecules. Given the protective role of tears a number of scenarios can be envisaged that may affect the amount and/or activity of tear antimicrobials and hence compromise tear immunity. Two such situations, dry eye disease and contact lens wear, are discussed here. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Fundamentals of the LISA stable flight formation

    International Nuclear Information System (INIS)

    Dhurandhar, S V; Nayak, K Rajesh; Koshti, S; Vinet, J-Y

    2005-01-01

    The joint NASA-ESA mission, LISA, relies crucially on the stability of the three-spacecraft constellation. Each of the spacecraft is in heliocentric orbit forming a stable triangle. In this paper we explicitly show with the help of the Clohessy-Wiltshire equations that any configuration of spacecraft lying in the planes making angles of ±60 0 with the ecliptic and given suitable initial velocities within the plane, can be made stable in the sense that the inter-spacecraft distances remain constant to first order in the dimensions of the configuration compared with the distance to the Sun. Such analysis would be useful in order to carry out theoretical studies on the optical links, simulators, etc

  7. A model for a stable coronal loop

    International Nuclear Information System (INIS)

    Hoven, G.V.; Chiuderi, C.; Giachetti, R.

    1977-01-01

    We present here a new plasma-physics model of a stable active-region arch which corresponds to the structure observed in the EUV. Pressure gradients are seen, so that the equilibrium magnetic field must depart from the force-free form valid in the surrounding corona. We take advantage of the data and of the approximate cylindrical symmetry to develop a modified form of the commonly assumed sheared-spiral structure. The dynamic MHD behavior of this new pressure/field model is then evaluated by the Newcomb criterion, taken from controlled-fusion physics, and the results show short-wavelength stability in a specific parameter range. Thus we demonstrate the possibility, for pressure profiles with widths of the order of the magnetic-field scale, that such arches can persist for reasonable periods. Finally, the spatial proportions and magnetic fields of a characteristic stable coronal loop are described

  8. Utilization of stable isotopes in medicine

    International Nuclear Information System (INIS)

    1980-11-01

    The ten lectures given at this round table are presented together with a discussion. Five lectures, relating to studies in which deuterium oxide was employed as a tracer of body water, dealt with pulmonary water measurements in man and animals, the total water pool in adipose subjects, and liquid compartments in children undergoing hemodyalisis. The heavy water is analysed by infrared spectrometry and a new double spectrodoser is described. Two studies using 13 C as tracer, described the diagnosis of liver troubles and diabetes respectively. A general review of the perspectives of the application of stable isotopes in clinical medicine is followed by a comparison of the use of stable and radioactive isotopes in France [fr

  9. Stable isotope enrichment: Current and future potential

    International Nuclear Information System (INIS)

    Tracy, J.G.; Aaron, W.S.

    1992-01-01

    Oak Ridge National Laboratory (ORNL) operates the Isotope Enrichment Facility for the purpose of providing enriched stable isotopes, selected radioactive isotopes (including the actinides), and isotope-related materials and services for use in various research applications. ORNL is responsible for isotope enrichment and the distribution of approximately 225 nongaseous stable isotopes from 50 multi-isotopic elements. Many enriched isotope products are of prime importance in the fabrication of nuclear targets and the subsequent production of special radionuclides. State-of-the-art techniques to achieve special isotopic, chemical, and physical requirements are performed at ORNL This report describes the status and capabilities of the Isotope Enrichment Facility and the Isotope Research Materials Laboratory as well as emphasizing potential advancements in enrichment capabilities

  10. Stable plastid transformation in Scoparia dulcis L.

    Science.gov (United States)

    Muralikrishna, Narra; Srinivas, Kota; Kumar, Kalva Bharath; Sadanandam, Abbagani

    2016-10-01

    In the present investigation we report stable plastid transformation in Scoparia dulcis L., a versatile medicinal herb via particle gun method. The vector KNTc, harbouring aadA as a selectable marker and egfp as a reporter gene which were under the control of synthetic promoter pNG1014a, targets inverted repeats, trnR / t rnN of the plastid genome. By use of this heterologous vector, recovery of transplastomic lines with suitable selection protocol have been successfully established with overall efficiency of two transgenic lines for 25 bombarded leaf explants. PCR and Southern blot analysis demonstrated stable integration of foreign gene into the target sequences. The results represent a significant advancement of the plastid transformation technology in medicinal plants, which relevantly implements a change over in enhancing and regulating of certain metabolic pathways.

  11. On The Roman Domination Stable Graphs

    Directory of Open Access Journals (Sweden)

    Hajian Majid

    2017-11-01

    Full Text Available A Roman dominating function (or just RDF on a graph G = (V,E is a function f : V → {0, 1, 2} satisfying the condition that every vertex u for which f(u = 0 is adjacent to at least one vertex v for which f(v = 2. The weight of an RDF f is the value f(V (G = Pu2V (G f(u. The Roman domination number of a graph G, denoted by R(G, is the minimum weight of a Roman dominating function on G. A graph G is Roman domination stable if the Roman domination number of G remains unchanged under removal of any vertex. In this paper we present upper bounds for the Roman domination number in the class of Roman domination stable graphs, improving bounds posed in [V. Samodivkin, Roman domination in graphs: the class RUV R, Discrete Math. Algorithms Appl. 8 (2016 1650049].

  12. Design of optically stable image reflector system.

    Science.gov (United States)

    Tsai, Chung-Yu

    2013-08-01

    The design of a partially optically stable (POS) reflector system, in which the exit ray direction and image pose are unchanged as the reflector system rotates about a specific directional vector, was presented in an earlier study by the current group [Appl. Phys. B100, 883-890 (2010)]. The present study further proposes an optically stable image (OSI) reflector system, in which not only is the optical stability property of the POS system retained, but the image position and total ray path length are also fixed. An analytical method is proposed for the design of OSI reflector systems comprising multiple reflectors. The validity of the proposed approach is demonstrated by means of two illustrative examples.

  13. Formation of stable radicals during perfluoroalkane radiolysis

    International Nuclear Information System (INIS)

    Allayarov, S.R.; Demidov, S.V.; Kiryukhin, D.P.; Mikhajlov, A.I.; Barkalov, I.M.

    1984-01-01

    Accumulation and stabilization kinetics of perfluoroalkyls during α-radiolysis ( 60 Co) of perfluoralkanes (PFA) in a wide temperature range for different PFA fractions differing in the average molecular weight, is investigated. It is noted that low temperature (PFA) radiolysis (77 K) is of a linear nature of accumulation of stabilized radicals up to doses of approximately 700 KGy. In the case of PFA radiolysis at 300 K radiation yields of stable radicals are somewhat lower than at 47 K and at doses of 200-300 KGy, their accumulation ceases. It is shown that kinetics of formation and accumulation of stable radicals does not depend on molecular mass and PFA fraction viscosity. Perfluoroalkyl stability is explained by intra molecular conformation spheric insulation of the free valency. Perfluoroalkyl stability in different PFA fractions in a wide time range in different media is investigated

  14. Stable isotope enrichment - current and future potential

    International Nuclear Information System (INIS)

    Tracy, J.G.; Aaron, W.S.

    1993-01-01

    Oak Ridge National Laboratory (ORNL) operates the Isotope Enrichment Facility for the purpose of providing enriched stable isotopes, selected radioactive isotopes (including the actinides), and isotope-related materials and services for use in various research applications. ORNL is responsible for isotope enrichment and the distribution of approximately 225 nongaseous stable isotopes from 50 multi-isotopic elements. Many enriched isotope products are of prime importance in the fabrication of nuclear targets and the subsequent production of special radionuclides. State-of-the-art techniques to achieve special isotopic, chemical, and physical requirements are performed at ORNL. This report describes the status and capabilities of the Isotope Enrichment Facility and the Isotope Research Materials Laboratory as well as emphasizing potential advancements in enrichment capabilities. (orig.)

  15. Synthesis of deuterium-labelled compounds for FOTEK project; Syntese af deuterium-maerkede forbindelser til FOeTEK projektet

    Energy Technology Data Exchange (ETDEWEB)

    Joergensen, O.; Egsgaard, H.; Larsen, E. [Forskningscenter Risoe, Roskilde (Denmark)

    1996-06-01

    In the FoTech project there have been utilized labelled compounds of stable isotopes as internal standards. Some of these compounds are commercially available ({sup 13}C-labelled PCB congeners, {sup 13}C-labelled diethylstilbestrol for determination of anabolic steroids). Others, like D{sub 9}-clenbuterol, D{sub 3}-clenbuterol, D{sub 3}-zeramol and D{sub 3}-dimetridazol have been synthesized. General aspects of deuterium compounds labelling are considered. (EG).

  16. Optimization of Parameters of Asymptotically Stable Systems

    Directory of Open Access Journals (Sweden)

    Anna Guerman

    2011-01-01

    Full Text Available This work deals with numerical methods of parameter optimization for asymptotically stable systems. We formulate a special mathematical programming problem that allows us to determine optimal parameters of a stabilizer. This problem involves solutions to a differential equation. We show how to chose the mesh in order to obtain discrete problem guaranteeing the necessary accuracy. The developed methodology is illustrated by an example concerning optimization of parameters for a satellite stabilization system.

  17. Multi-Stable Morphing Cellular Structures

    Science.gov (United States)

    2015-05-14

    stiffness on critical buckling load and arch stres - ses. It should be noted that although the arches in these studies snapped-through, they did not...switch roles in moving the VMT back from the second to the first stable equilibrium state. A prototype is designed and fabricated and the transition...pulling forward on the insert on the right blade and assisting its deployment. During this process the cable 3-4-1 goes slack and plays no role , but if

  18. The nature of stable insomnia phenotypes.

    Science.gov (United States)

    Pillai, Vivek; Roth, Thomas; Drake, Christopher L

    2015-01-01

    We examined the 1-y stability of four insomnia symptom profiles: sleep onset insomnia; sleep maintenance insomnia; combined onset and maintenance insomnia; and neither criterion (i.e., insomnia cases that do not meet quantitative thresholds for onset or maintenance problems). Insomnia cases that exhibited the same symptom profile over a 1-y period were considered to be phenotypes, and were compared in terms of clinical and demographic characteristics. Longitudinal. Urban, community-based. Nine hundred fifty-four adults with Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition based current insomnia (46.6 ± 12.6 y; 69.4% female). None. At baseline, participants were divided into four symptom profile groups based on quantitative criteria. Follow-up assessment 1 y later revealed that approximately 60% of participants retained the same symptom profile, and were hence judged to be phenotypes. Stability varied significantly by phenotype, such that sleep onset insomnia (SOI) was the least stable (42%), whereas combined insomnia (CI) was the most stable (69%). Baseline symptom groups (cross-sectionally defined) differed significantly across various clinical indices, including daytime impairment, depression, and anxiety. Importantly, however, a comparison of stable phenotypes (longitudinally defined) did not reveal any differences in impairment or comorbid psychopathology. Another interesting finding was that whereas all other insomnia phenotypes showed evidence of an elevated wake drive both at night and during the day, the 'neither criterion' phenotype did not; this latter phenotype exhibited significantly higher daytime sleepiness despite subthreshold onset and maintenance difficulties. By adopting a stringent, stability-based definition, this study offers timely and important data on the longitudinal trajectory of specific insomnia phenotypes. With the exception of daytime sleepiness, few clinical differences are apparent across stable phenotypes.

  19. Strongly stable real infinitesimally symplectic mappings

    NARCIS (Netherlands)

    Cushman, R.; Kelley, A.

    We prove that a mapA εsp(σ,R), the set of infinitesimally symplectic maps, is strongly stable if and only if its centralizerC(A) insp(σ,R) contains only semisimple elements. Using the theorem that everyB insp(σ,R) close toA is conjugate by a real symplectic map to an element ofC(A), we give a new

  20. A belief-based evolutionarily stable strategy

    OpenAIRE

    Deng, Xinyang; Wang, Zhen; Liu, Qi; Deng, Yong; Mahadevan, Sankaran

    2014-01-01

    As an equilibrium refinement of the Nash equilibrium, evolutionarily stable strategy (ESS) is a key concept in evolutionary game theory and has attracted growing interest. An ESS can be either a pure strategy or a mixed strategy. Even though the randomness is allowed in mixed strategy, the selection probability of pure strategy in a mixed strategy may fluctuate due to the impact of many factors. The fluctuation can lead to more uncertainty. In this paper, such uncertainty involved in mixed st...

  1. Production of fungal volatile organic compounds in bedding materials

    Directory of Open Access Journals (Sweden)

    S. LAPPALAINEN

    2008-12-01

    Full Text Available The high relative humidity of the air and many potential growth media, such as bedding materials, hay and grains in the horse stable, for example, provide suitable conditions for fungal growth. Metabolic activity of four common agricultural fungi incubated in peat and wood shavings at 25°C and 4°C was characterized in this study using previously specified volatile metabolites of micro-organisms and CO 2 production as indicators. The volatile organic compounds were collected into Tenax resin and analysed by gas chromatography. Several microbial volatile organic compounds (MVOCs, e.g. 1-butanol, 2-hexanone, 2-heptanone, 3-octanone, 1-octen-3-ol and 1-octanol were detected in laboratory experiments; however, these accounted for only 0.08-1.5% of total volatile organic com-pounds (TVOCs. Emission rates of MVOCs were 0.001-0.176 mg/kg of bedding materials per hour. Despite some limitations of the analytical method, certain individual MVOCs, 2-hexanone, 2-hep-tanone and 3-octanone, were also detected in concentrations of less than 4.6 mg/m 3 (0.07-0.31% of TVOC in a horse stable where peat and shavings were used as bedding materials. MVOC emission rate was estimated to be 0.2-2.0 mg/kg ´ h -1 from bedding materials in the stable, being about ten times higher than the rates found in the laboratory experiments. Some compounds, e.g. 3-octanone and 1-octen-3-ol, can be assumed to originate mainly from microbial metabolisms.;

  2. Mechanical Properties of Stable Glasses Using Nanoindentation

    Science.gov (United States)

    Wolf, Sarah; Liu, Tianyi; Jiang, Yijie; Ablajan, Keyume; Zhang, Yue; Walsh, Patrick; Turner, Kevin; Fakhraai, Zahra

    Glasses with enhanced stability over ordinary, liquid quenched glasses have been formed via the process of Physical Vapor Deposition (PVD) by using a sufficiently slow deposition rate and a substrate temperature slightly below the glass transition temperature. These stable glasses have been shown to exhibit higher density, lower enthalpy, and better kinetic stability over ordinary glass, and are typically optically birefringent, due to packing and orientational anisotropy. Given these exceptional properties, it is of interest to further investigate how the properties of stable glasses compare to those of ordinary glass. In particular, the mechanical properties of stable glasses remain relatively under-investigated. While the speed of sound and elastic moduli have been shown to increase with increased stability, little is known about their hardness and fracture toughness compared to ordinary glasses. In this study, glasses of 9-(3,5-di(naphthalen-1-yl)phenyl)anthracene were deposited at varying temperatures relative to their glass transition temperature, and their mechanical properties measured by nanoindentation. Hardness and elastic modulus of the glasses were compared across substrate temperatures. After indentation, the topography of these films were studied using Atomic Force Microscopy (AFM) in order to further compare the relationship between thermodynamic and kinetic stability and mechanical failure. Z.F. and P.W. acknowledge funding from NSF(DMREF-1628407).

  3. Detonation of Meta-stable Clusters

    Energy Technology Data Exchange (ETDEWEB)

    Kuhl, Allen; Kuhl, Allen L.; Fried, Laurence E.; Howard, W. Michael; Seizew, Michael R.; Bell, John B.; Beckner, Vincent; Grcar, Joseph F.

    2008-05-31

    We consider the energy accumulation in meta-stable clusters. This energy can be much larger than the typical chemical bond energy (~;;1 ev/atom). For example, polymeric nitrogen can accumulate 4 ev/atom in the N8 (fcc) structure, while helium can accumulate 9 ev/atom in the excited triplet state He2* . They release their energy by cluster fission: N8 -> 4N2 and He2* -> 2He. We study the locus of states in thermodynamic state space for the detonation of such meta-stable clusters. In particular, the equilibrium isentrope, starting at the Chapman-Jouguet state, and expanding down to 1 atmosphere was calculated with the Cheetah code. Large detonation pressures (3 and 16 Mbar), temperatures (12 and 34 kilo-K) and velocities (20 and 43 km/s) are a consequence of the large heats of detonation (6.6 and 50 kilo-cal/g) for nitrogen and helium clusters respectively. If such meta-stable clusters could be synthesized, they offer the potential for large increases in the energy density of materials.

  4. Clinically stable angina pectoris is not necessarily associated with histologically stable atherosclerotic plaques

    NARCIS (Netherlands)

    van der Wal, A. C.; Becker, A. E.; Koch, K. T.; Piek, J. J.; Teeling, P.; van der Loos, C. M.; David, G. K.

    1996-01-01

    OBJECTIVE: To investigate the extent of plaque inflammation in culprit lesions of patients with chronic stable angina. DESIGN: Retrospective study. SETTING: Amsterdam reference centre. SUBJECTS: 89 consecutive patients who underwent directional coronary atherectomy, 58 of whom met the following

  5. II-VI semiconductor compounds

    CERN Document Server

    1993-01-01

    For condensed matter physicists and electronic engineers, this volume deals with aspects of II-VI semiconductor compounds. Areas covered include devices and applications of II-VI compounds; Co-based II-IV semi-magnetic semiconductors; and electronic structure of strained II-VI superlattices.

  6. Compound-heterozygous Marfan syndrome

    NARCIS (Netherlands)

    van Dijk, F. S.; Hamel, B. C.; Hilhorst-Hofstee, Y.; Mulder, B. J. M.; Timmermans, J.; Pals, G.; Cobben, J. M.

    2009-01-01

    We report two families in which the probands have compound-heterozygous Marfan syndrome (MFS). The proband of family I has the R2726W FBN1 mutation associated with isolated skeletal features on one allele and a pathogenic FBN1 mutation on the other allele. The phenotype of the compound-heterozygous

  7. Radioactive decay and labeled compounds

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    This chapter on radioactive decay and labeled compounds has numerous intext equations and worked, sample problems. Topics covered include the following: terms and mathematics of radioactive decay; examples of calculations; graphs of decay equations; radioactivity or activity; activity measurements; activity decay; half-life determinations; labeled compounds. A 20 problem set is also included. 1 ref., 4 figs., 1 tab

  8. 2. Intermetallic compounds with lanthanides

    International Nuclear Information System (INIS)

    Elemans, J.B.A.A.

    1975-01-01

    Theoretical considerations are given concerning the structures of intermetallic compounds of the lanthanides and thorium (R) on the one hand, and with Fe, Co or Ni (M) on the other. They all derive from the parent composition RM 5 with the CaCu 5 hexagonal structure. This consists of alternate layers in which the M atoms are distinguished as M 1 and M 2 . The other compounds whose structures are studied are obtained by systematic replacement of R by M, or vice versa. In the first type, every third R is replaced by two M's yielding R 2 M 17 compounds. The substitution may be truly random or structured in two ways: so that either the hexagonal structure is maintained or that it is converted into a rhombihedral one. In the second type, one M (in a M 1 position) out of every five is replaced by one R, giving rise to RM 2 compounds which form Laves phases. In the third type, the M 1 's are replaced by R's, resulting in compounds RM 3 . In the fourth type, every third M is replaced by R, yielding R 2 M 7 compounds. With M = Co and R a light lanthanide, the compounds are ferromagnets; with R yttrium, thorium, or a heavy lanthanide, they are ferrimagnets. The preparation of the compounds in an arc-melting apparatus under an Ar-atmosphere followed by annealing is described

  9. Xenobiotic organic compounds in wastewater

    DEFF Research Database (Denmark)

    Eriksson, Eva; Baun, Anders; Henze, Mogens

    2002-01-01

    hundred of XOCs, among them mainly originating from hygiene products: chlorophenols, detergents and phthalates. Several compounds not deriving from hygiene products were also identified e.g. flame-retardants and drugs. A environmental hazard identification showed that a large number of compounds with high...

  10. Devices for collecting chemical compounds

    Science.gov (United States)

    Scott, Jill R; Groenewold, Gary S

    2013-12-24

    A device for sampling chemical compounds from fixed surfaces and related methods are disclosed. The device may include a vacuum source, a chamber and a sorbent material. The device may utilize vacuum extraction to volatilize the chemical compounds from a fixed surface so that they may be sorbed by the sorbent material. The sorbent material may then be analyzed using conventional thermal desorption/gas chromatography/mass spectrometry (TD/GC/MS) instrumentation to determine presence of the chemical compounds. The methods may include detecting release and presence of one or more chemical compounds and determining the efficacy of decontamination. The device may be useful in collection and analysis of a variety of chemical compounds, such as residual chemical warfare agents, chemical attribution signatures and toxic industrial chemicals.

  11. Multivariate Stable Isotope Analysis to Determine Linkages between Benzocaine Seizures

    Science.gov (United States)

    Kemp, H. F.; Meier-Augenstein, W.; Collins, M.; Salouros, H.; Cunningham, A.; Harrison, M.

    2012-04-01

    In July 2010, a woman was jailed for nine years in the UK after the prosecution successfully argued that attempting to import a cutting agent was proof of involvement in a conspiracy to supply Cocaine. That landmark ruling provided law enforcement agencies with much greater scope to tackle those involved in this aspect of the drug trade, specifically targeting those importing the likes of benzocaine or lidocaine. Huge quantities of these compounds are imported into the UK and between May and August 2010, four shipments of Benzocaine amounting to more then 4 tons had been seized as part of Operation Kitley, a joint initiative between the UK Border Agency and the Serious Organised Crime Agency (SOCA). By diluting cocaine, traffickers can make it go a lot further for very little cost, leading to huge profits. In recent years, dealers have moved away from inert substances, like sugar and baby milk powder, in favour of active pharmaceutical ingredients (APIs), including anaesthetics like Benzocaine and Lidocaine. Both these mimic the numbing effect of cocaine, and resemble it closely in colour, texture and some chemical behaviours, making it easier to conceal the fact that the drug has been diluted. API cutting agents have helped traffickers to maintain steady supplies in the face of successful interdiction and even expand the market in the UK, particularly to young people aged from their mid teens to early twenties. From importation to street-level, the purity of the drug can be reduced up to a factor of 80 and street level cocaine can have a cocaine content as low as 1%. In view of the increasing use of Benzocaine as cutting agent for Cocaine, a study was carried out to investigate if 2H, 13C, 15N and 18O stable isotope signatures could be used in conjunction with multivariate chemometric data analysis to determine potential linkage between benzocaine exhibits seized from different locations or individuals to assist with investigation and prosecution of drug

  12. Thermal stability of LiNaR2F8 compounds (R=Ho-Lu, Y)

    International Nuclear Information System (INIS)

    Fedorov, P.P.; Medvedeva, L.V.; Bondareva, O.S.; Sobolev, B.P.

    1990-01-01

    Monoclinic pseudorhombic compound mentioned in the title are investigated. It is determined, that the compounds are stable within temperature narrow range: Ho - 575-693 degC, Er - 566-712deg C, Tm - 560-710 deg C, Yb - less than 685 deg C, Y - 580-712 deg C. Triangulation of LiF-NaF-YF 3 system is carried out

  13. Identification and characterization of haemofungin, a novel antifungal compound that inhibits the final step of haem biosynthesis.

    Science.gov (United States)

    Ben Yaakov, Dafna; Rivkin, Anna; Mircus, Gabriel; Albert, Nathaniel; Dietl, Anna-Maria; Kovalerchick, Dimitry; Carmeli, Shmuel; Haas, Hubertus; Kontoyiannis, Dimitrios P; Osherov, Nir

    2016-04-01

    During recent decades, the number of invasive fungal infections among immunosuppressed patients has increased significantly, whereas the number of effective systemic antifungal drugs remains low and unsatisfactory. The aim of this study was to characterize a novel antifungal compound, CW-8/haemofungin, which we previously identified in a screen for compounds affecting fungal cell wall integrity. The in vitro characteristics of haemofungin were investigated by MIC evaluation against a panel of pathogenic and non-pathogenic fungi, bacteria and mammalian cells in culture. Haemofungin mode-of-action studies were performed by screening an Aspergillus nidulans overexpression genomic library for resistance-conferring plasmids and biochemical validation of the target. In vivo efficacy was tested in the Galleria mellonella and Drosophila melanogaster insect models of infection. We demonstrate that haemofungin causes swelling and lysis of growing fungal cells. It inhibits the growth of pathogenic Aspergillus, Candida, Fusarium and Rhizopus isolates at micromolar concentrations, while only weakly affecting the growth of mammalian cell lines. Genetic and biochemical analyses in A. nidulans and Aspergillus fumigatus indicate that haemofungin primarily inhibits ferrochelatase (HemH), the last enzyme in the haem biosynthetic pathway. Haemofungin was non-toxic and significantly reduced mortality rates of G. mellonella and D. melanogaster infected with A. fumigatus and Rhizopus oryzae, respectively. Further development and in vivo validation of haemofungin is warranted. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  14. HPLC-DAD-ESI/MS(n) analysis of phenolic compounds for quality control of Grindelia robusta Nutt. and bioactivities.

    Science.gov (United States)

    Ferreres, Federico; Grosso, Clara; Gil-Izquierdo, Angel; Valentão, Patrícia; Azevedo, Carolina; Andrade, Paula B

    2014-06-01

    The phenolic composition of herbal tea (HT) and hydromethanolic extract (HME) obtained from Grindelia robusta Nutt. was studied by HPLC-DAD-ESI/MS(n). Thirty six flavonoids and hydroxycinnamic acids were detected, from which thirty are described for the first time in this species. Quantification by HPLC-DAD showed that diosmetin-7-O-glucuronide-3'-O-pentoside+apigenin-7-O-glucuronide-4'-O-pentoside, apigenin-7-O-glucuronide+diosmetin-7-O-glucuronide and 3,5-dicaffeoylquinic acid+3,4-dicaffeoylquinic acid were the major compounds. Since the health-promoting effects of natural phenolic compounds against brain disorders is of increasing interest, HT and HME were also tested against oxygen and nitrogen reactive species and against enzymes related with Alzheimer's disease and depression. Extracts displayed strong in vitro scavenging activity and monoamine oxidase-A (MAO-A) inhibitory activity. The anti-MAO-A capacity was observed at non-toxic concentrations for SH-SY5Y human neuroblastoma cell line, reinforcing the benefits of G. robusta HT. However, no protection against hydrogen peroxide treatment was observed. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. First-principles calculations of two cubic fluoropervskite compounds: RbFeF3 and RbNiF3

    International Nuclear Information System (INIS)

    Mubarak, A.A.; Al-Omari, Saleh

    2015-01-01

    We present first-principles calculations of the structural, elastic, electronic, magnetic and optical properties for RbFeF 3 and RbNiF 3 . The full-potential linear augmented plan wave (FP-LAPW) method within the density functional theory was utilized to perform the present calculations. We employed the generalized gradient approximation as exchange-correlation potential. It was found that the calculated analytical lattice parameters agree with previous studies. The analysis of elastic constants showed that the present compounds are elastically stable and anisotropic. Moreover, both compounds are classified as a ductile compound. The calculations of the band structure and density functional theory revealed that the RbFeF 3 compound has a half-metallic behavior while the RbNiF 3 compound has a semiconductor behavior with indirect (M–Γ) band gap. The ferromagnetic behavior was studied for both compounds. The optical properties were calculated for the radiation of up to 40 eV. A beneficial optics technology is predicted as revealed from the optical spectra. - Highlights: • RbFeF 3 and RbNiCl 3 compounds are elastically stable. • RbFeF 3 and RbNiCl 3 compounds are classified as a ductile compound. • The RbFeF 3 compound has a half-metallic behavior while the RbNiF 3 compound has a semiconductor behavior. • The optical properties were calculated for the radiation of up to 40 eV

  16. Novel phases and superconductivity of tin sulfide compounds

    Science.gov (United States)

    Gonzalez, Joseph M.; Nguyen-Cong, Kien; Steele, Brad A.; Oleynik, Ivan I.

    2018-05-01

    Tin sulfides, SnxSy, are an important class of materials that are actively investigated as novel photovoltaic and water splitting materials. A first-principles evolutionary crystal structure search is performed with the goal of constructing the complete phase diagram of SnxSy and discovering new phases as well as new compounds of varying stoichiometry at ambient conditions and pressures up to 100 GPa. The ambient phase of SnS2 with P 3 ¯ m 1 symmetry remains stable up to 28 GPa. Another ambient phase, SnS, experiences a series of phase transformations including α-SnS to β-SnS at 9 GPa, followed by β-SnS to γ-SnS at 40 GPa. γ-SnS is a new high-pressure metallic phase with P m 3 ¯ m space group symmetry stable up to 100 GPa, which becomes a superconductor with a maximum Tc = 9.74 K at 40 GPa. Another new metallic compound, Sn3S4 with I 4 ¯ 3 d space group symmetry, is predicted to be stable at pressures above 15 GPa, which also becomes a superconductor with relatively high Tc = 21.9 K at 30 GPa.

  17. Multi-angle compound imaging

    DEFF Research Database (Denmark)

    Jespersen, Søren Kragh; Wilhjelm, Jens Erik; Sillesen, Henrik

    1998-01-01

    This paper reports on a scanning technique, denoted multi-angle compound imaging (MACI), using spatial compounding. The MACI method also contains elements of frequency compounding, as the transmit frequency is lowered for the highest beam angles in order to reduce grating lobes. Compared to conve......This paper reports on a scanning technique, denoted multi-angle compound imaging (MACI), using spatial compounding. The MACI method also contains elements of frequency compounding, as the transmit frequency is lowered for the highest beam angles in order to reduce grating lobes. Compared...... to conventional B-mode imaging MACI offers better defined tissue boundaries and lower variance of the speckle pattern, resulting in an image with reduced random variations. Design and implementation of a compound imaging system is described, images of rubber tubes and porcine aorta are shown and effects...... on visualization are discussed. The speckle reduction is analyzed numerically and the results are found to be in excellent agreement with existing theory. An investigation of detectability of low-contrast lesions shows significant improvements compared to conventional imaging. Finally, possibilities for improving...

  18. Stable isotope studies of nicotine kinetics and bioavailability

    International Nuclear Information System (INIS)

    Benowitz, N.L.; Jacob, P. III; Denaro, C.; Jenkins, R.

    1991-01-01

    The stable isotope-labeled compound 3',3'-dideuteronicotine was used to investigate the disposition kinetics of nicotine in smokers, the systemic absorption of nicotine from cigarette smoke, and the bioavailability of nicotine ingested as oral capsules. Blood levels of labeled nicotine could be measured for 9 hours after a 30-minute intravenous infusion. Analysis of disposition kinetics in 10 healthy men revealed a multiexponential decline after the end of an infusion, with an elimination half-life averaging 203 minutes. This half-life was longer than that previously reported, indicating the presence of a shallow elimination phase. Plasma clearance averaged 14.6 ml/min/kg. The average intake of nicotine per cigarette was 2.29 mg. A cigarette smoke-monitoring system that directly measured particulate matter in smoke was evaluated in these subjects. Total particulate matter, number of puffs on the cigarette, total puff volume, and time of puffing correlated with the intake of nicotine from smoking. The oral bioavailability of nicotine averaged 44%. This bioavailability is higher than expected based on the systemic clearance of nicotine and suggests that there may be significant extrahepatic metabolism of nicotine

  19. NMR-based stable isotope resolved metabolomics in systems biochemistry

    International Nuclear Information System (INIS)

    Fan, Teresa W-M.; Lane, Andrew N.

    2011-01-01

    An important goal of metabolomics is to characterize the changes in metabolic networks in cells or various tissues of an organism in response to external perturbations or pathologies. The profiling of metabolites and their steady state concentrations does not directly provide information regarding the architecture and fluxes through metabolic networks. This requires tracer approaches. NMR is especially powerful as it can be used not only to identify and quantify metabolites in an unfractionated mixture such as biofluids or crude cell/tissue extracts, but also determine the positional isotopomer distributions of metabolites derived from a precursor enriched in stable isotopes such as 13 C and 15 N via metabolic transformations. In this article we demonstrate the application of a variety of 2-D NMR editing experiments to define the positional isotopomers of compounds present in polar and non-polar extracts of human lung cancer cells grown in either [U– 13 C]-glucose or [U– 13 C, 15 N]-glutamine as source tracers. The information provided by such experiments enabled unambiguous reconstruction of metabolic pathways, which is the foundation for further metabolic flux modeling.

  20. Phenol Contaminated Water Treatment on Several Modified Dimensionally Stable Anodes.

    Science.gov (United States)

    Jayathilaka, Pavithra Bhakthi; Hapuhinna, Kushani Umanga Kumari; Bandara, Athula; Nanayakkara, Nadeeshani; Subasinghe, Nalaka Deepal

    2017-08-01

      Phenolic compounds are some of the most common hazardous organics in wastewater. Removal of these pollutants is important. Physiochemical method such as electrochemical oxidation on dimensionally stable anodes is more convenient in removing such organic pollutants. Therefore, this study focuses on development of three different anodes for phenol contaminated water treatment. The performances of steel/IrO2, steel/IrO2-Sb2O3, and Ti/IrO2-Sb2O3 anodes were tested and compared. Nearly 50, 76, and 84% of chemical oxygen demand removal efficiencies were observed for steel/IrO2, steel/IrO2-Sb2O3, and Ti/IrO2-Sb2O3 anodes, respectively. The formation of intermediates was monitored for three anodes and the Ti/IrO2-Sb2O3 anode showed the most promising results. Findings suggest that the developed anode materials can enhance phenol oxidation efficiency and that mixed metal oxide layer has major influence on the anode. Among the selected metal oxide mixtures IrO2-Sb2O3 was the most suitable under given experimental conditions.