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Sample records for brevis natural chemical

  1. Chemical and natural stressors combined:

    DEFF Research Database (Denmark)

    Gergs, André; Zenker, Armin; Grimm, Volker

    2013-01-01

    In addition to natural stressors, populations are increasingly exposed to chemical pollutants released into the environment. We experimentally demonstrate the loss of resilience for Daphnia magna populations that are exposed to a combination of natural and chemical stressors even though effects...... demonstrates that population size can be a poor endpoint for risk assessments of chemicals and that ignoring disturbance interactions can lead to severe underestimation of extinction risk...

  2. Chemical composition of essential oils of Drimys angustifolia Miers and Drimys brasiliensis Miers and their repellency to drywood termite Cryptotermes brevis (Isoptera: Kalotermitidae

    Directory of Open Access Journals (Sweden)

    Madson Ralide Fonseca Gomes

    2014-01-01

    Full Text Available The essential oils extracted from leaves of the Southern Brazilian native species Drimys angustifolia Miers (DA and Drimys brasiliensis Miers (DB by Clevenger distillation were analyzed by gas chromatography/ mass spectrometry (GC/MS. The oils of DA and DB consisted predominantly of monoterpenoids and sesquiterpenoids. The largest components of DA oil were bicyclogermacrene (19.6%, sabinene (9.7% and myrcene (5.2%, while DB oil was characterized by cyclocolorenone (18.2%, followed by terpinen-4- ol (8.7% and alpha-gurjunene (6.9%. Laboratory tests were carried out to determine the repellency of the essential oils to the drywood termite Cryptotermes brevis (Isoptera: Kalotermitidae. It was observed that the oil showed repellency at the concentrations 25, 12.5, and 6.25 μg/mL. The oils of both species exhibited a negative repellency index, which represents repellent activity, except for DA oil at the highest concentration, which was attractive. Five deaths (11% of the termite sample were observed at 25 μg/mL DA, in the fourhour repellency test, while four deaths occurred at 12.5 μg/mL (approximately 9%. The essential oil of DB did not cause any termite deaths.

  3. Isolation and molecular identification of Lactobacillus brevis from traditional vinegar

    Directory of Open Access Journals (Sweden)

    Zeynab Ebrahimi

    2016-09-01

    Full Text Available Introduction: Vinegar is a popular condiment in the world that different materials and methods have been used to produce it. In Iran natural vinegar is also prepared mostly in a traditional way by using different fruits such as grapes and apples. Natural vinegar has beneficent properties and because of this, it is recommended to be used by traditional and Islamic medicine. Vinegar contains acetic acid bacteria, lactic acid bacteria and yeast. Acetic acid bacteria and yeasts are involved in the production of vinegar and lactic acid bacteria improve the flavor of vinegar. The aim of this study was isolation and identification of lactic acid bacteria especially Lactobacillus brevis from traditional vinegar. Materials and methods: After collecting a few traditional vinegars, the vinegar samples cultured for isolation of lactic acid bacteria on MRS broth and agar media contained nystatin as an anti-yeast antibiotic. Then some microbiological tests including catalase, gram staining and fermentation of carbohydrates were performed. Then, they were cultured at different temperatures, pH and different concentrations of salts. Finally, three isolates bacteria with biochemical properties of Lactobacillus brevis were evaluated by16 srDNA gene amplification. Results: Twelve lactobacilli were isolated from three vinegar samples. All isolated bacteria were catalase-negative and gram-positive. They could be able to grow at pH around 4.5 and 5.6, and at 2, 4 and 5.6% of salt concentrations. Most of the bacteria grew at 15oC, whereas one isolated grew at 45oC. Sequencing and Blast results showed that the three strains are Lactobacillus brevis. Discussion and conclusion: Lactobacillus brevis and Lactobacillus plantrum were found in traditional vinegars. Although isolation of Lactobacillus plantrum from vinegar was reported previously, as far as we could determine, it is for the first time that we could isolate Lactobacillus brevis from vinegar.

  4. Natural radiation, nuclear wastes and chemical pollutants

    International Nuclear Information System (INIS)

    Christensen, T.; Ehdwall, H.; Stranden, E.

    1990-01-01

    Doses from natural radiation to the population in the Nordic Countries are summarized and man made modifications of the natural radiation environment are discussed. An account is given of the radiological consequences of energy conservation by reduced ventilation. Risks from possible future releases of radioactivity from final repositories of spent nuclear fuel are compared to the risks from present natural radioactivity in the environment. The possibilities for comparison between chemical and radiological risks are discussed. (author) 13 refs

  5. Chemical modifications of liquid natural rubber

    Science.gov (United States)

    Azhar, Nur Hanis Adila; Rasid, Hamizah Md; Yusoff, Siti Fairus M.

    2016-11-01

    Liquid natural rubber (LNR) was synthesized via photosentisized degradation of natural rubber (NR). LNR was modified into epoxidized liquid natural rubber (LENR) and hydroxylated liquid natural rubber (LNR-OH) using Na2WO4/CH3COOH/H2O2 catalytic system. Chemical structures of LNR and modified LNRs were characterized using Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) and 1H Nuclear Magnetic Resonance (NMR) spectroscopies. Integration of 1H NMR was used to calculate the epoxy content (%) of LENR. 1H NMR detected the formation of LNR-OH after prolonged heating and increased of catalyst in oxidation reaction.

  6. The Effect of Various Species of Macroalgae on the Growth, Survival, and Toxicity of Karenia brevis

    Science.gov (United States)

    Gardner, K. G.; Lovko, V. J.; Henry, M. S.

    2016-02-01

    Harmful algal blooms (HABs) caused by the dinoflagellate Karenia brevis produce toxins that result in negative impacts to both humans and the environment. Little is known about the termination stages of these blooms, and few viable control mechanisms have been suggested. Natural, algae derived compounds have been proposed as a way to limit bloom growth and reduce brevetoxins in the water column. The work presented here examines the ability of macroalgae to inhibit the growth or survival of K. brevis, similar to what has been demonstrated with other red tide species. Additionally, we attempted to determine if macroalgae decreases water column brevetoxins which, to our knowledge, has not been tested with macroalgae but has been demonstrated in other studies with microalgal species. The macroalgae species Dictyota sp. and Gracilaria sp. caused 100% mortality of K. brevis in under 24 hours. Compared to the control, 7 other species significantly decreased the growth rate of K. brevis. The Dictyota treatments showed significant toxin reduction and increase of the antitoxin brevanol. These results indicate that some combination of compounds produced by macroalgae inhibit growth and survival of K. brevis and possibly limit their toxin production. Future studies will attempt to isolate and identify these compounds and test their effects on other marine organisms such as diatoms. Determining the interactions between HAB species K. brevis and macroalgal species will provide insights on the mechanism of bloom termination and a potential control method.

  7. Chemical speciation of Pu in natural waters

    International Nuclear Information System (INIS)

    Nelson, D.M.; Larsen, R.P.; Penrose, W.R.

    1983-01-01

    The behavior of plutonium in natural waters is determined to a major degree by the chemical forms which are present. We have characterized the ambient Pu in a number of surface waters with regard to its oxidation state and association with natural colloidal organic carbon compounds using a combination of field measurements and laboratory experiments. Both of these factors are shown to have a profound effect on the adsorption of Pu to natural sediments, since both complexation with organic matter and oxidation compete with adsorption. The concentration of organic carbon in the water is the key variable influencing both oxidation state and organic binding. The adsorption process conforms to the laws applicable to a reversible equilibrium with values of the distribution coefficient, K/sub D/, measured in laboratory experiments being similar to those observed for ambient Pu. Experiments using natural waters and sediments in which the Pu concentration was varied show the forms present at typical ambient concentrations (10 -17 - 10 -14 M) are the same as those found at concentrations up to 10 -7 M. Moreover, the affinity for sediments did not change with concentration indicating the binding sites for Pu had not become saturated. Thus, the behavior observed for Pu at ultratrace concentrations should remain unchanged throughout this concentration range. The studies in this report all deal with Pu in exchangeable (and hence source independent) forms and should therefore reflect the behavior toward which the plutonium from any source will tend with time. 13 references, 7 figures, 10 tables

  8. Specific aminopeptidases of indigenous Lactobacillus brevis and ...

    African Journals Online (AJOL)

    Lactic acid bacteria play an important role in milk coagulation and cheese ripening. To select strains showing interesting industrial features, two indigenous lactobacilli (Lactobacillus brevis and Lactobacillus plantarum) were studied for aminopeptidase activity. Cell and cells free extract were tested for leucyl aminopeptidase ...

  9. Physical and chemical investigations on natural dyes

    Science.gov (United States)

    Acquaviva, S.; D'Anna, E.; de Giorgi, M. L.; Della Patria, A.; Baraldi, P.

    2010-09-01

    Natural dyes have been used extensively in the past for many purposes, such us to colour fibers and to produce inks, watercolours and paints, but their use declined rapidly after the discovery of synthetic colours. Nowadays we witness a renewed interest, as natural dyes are neither toxic nor polluting. In this work, physical and chemical properties of four selected dyes, namely red (Madder), yellow (Weld and Turmeric) and blue (Woad) colours, produced by means of traditional techniques at the Museo dei Colori Naturali (Lamoli, Italy), have been investigated. The chromatic properties have been studied through the reflectance spectroscopy, a non-invasive technique for the characterisation of chromaticity. Reflection spectra both from powders and egg-yolk tempera models have been acquired to provide the typical features of the dyes in the UV-vis spectral range. Moreover, to assess the feasibility of laser cleaning procedures, tempera layers were investigated after irradiation with an excimer laser. Micro Raman spectroscopy, Scanning Electron Microscopy and Energy Dispersive X-Ray analyses have complemented the survey, returning compositional and morphological information as well. Efforts have been made to give scientific feedback to the production processes and to support the research activity in the restoration of the artworks where these dyes were employed.

  10. Chemical deacetylation natural xanthan (Jungbunzlauer®

    Directory of Open Access Journals (Sweden)

    Ellen P. Pinto

    2011-01-01

    Full Text Available With the aim of adapting a method for removal of acetyl groups from xanthan, reactions of chemical deacetylation were carried out with natural xanthan (Jungbunzlauer® with variations on the following parameters: biopolymer and alkali concentration (sodium and potassium hydroxide. The deacetylation reaction was performed at 25 ºC for three hours. The proposed methodology was efficient to promote the deacetylation reaction. The viscosity of xanthan increased when the alkali concentration was higher in the deacetylation reaction. Xanthan concentration in the solution used in the deacetylation reaction did not influence the solutions viscosity, as similar results in both tested biopolymer concentrations (0.5 and 1% were obtained for all experiments in different shear rates. Deacetylation reactions at 25 ºC for three hours with sodium and potassium hydroxide in 0.01 mol.L-1 showed a viscosity of 410 and 420 mPa.s at 10 s-1 and acetylation degree 1.3 e 1.4%, respectively.

  11. Enthesopathy of the Extensor Carpi Radialis Brevis Origin: Effective Communication Strategies.

    Science.gov (United States)

    Drake, Matthew L; Ring, David C

    2016-06-01

    Enthesopathy of the extensor carpi radialis brevis origin, generally known as tennis elbow, is a common condition arising in middle-aged persons. The diagnosis is typically clear based on the patient interview and physical examination alone; therefore, imaging and other diagnostic tests are usually unnecessary. The natural history of the disorder is spontaneous resolution, but it can last for >1 year. The patient's attitude and circumstances, including stress, distress, and ineffective coping strategies, determine the intensity of the pain and the magnitude of the disability. Despite the best efforts of medical science, no treatments, invasive or noninvasive, have been proven to alter the natural history of the condition. Given the lack of disease-modifying treatments for enthesopathy of the extensor carpi radialis brevis origin, orthopaedic surgeons can benefit from learning effective communication strategies to help convey accurate information that is hopeful and enabling.

  12. Chemical Biology of Microbial Anticancer Natural Products

    DEFF Research Database (Denmark)

    Bladt, Tanja Thorskov; Gotfredsen, Charlotte Held

    than 100 years. New natural products (NPs) are continually discovered and with the increase in selective biological assays, previously described compounds often also display novel bioactivities, justifying their presence in novel screening efforts. Screening and discovery of compounds with activity...... towards chronic lymphocytic leukemia (CLL) cells is crucial since CLL is considered as an incurable disease. To discover novel agents that targets CLL cells is complicated. CLL cells rapidly undergo apoptosis in vitro when they are removed from their natural microenvironment, even though they are long...

  13. Atlantic Forest. A natural reservoir of chemical elements

    International Nuclear Information System (INIS)

    De Franca, E.J.; De Nadai Fernandes, E.A.; Bacchi, M.A.; Elias, C.

    2008-01-01

    The accumulation of chemical elements in biological compartments is one of the strategies of tropical species to adapt to a low-nutrient soil. This study focuses on the Atlantic Forest because of its eco-environmental importance as a natural reservoir of chemical elements. About 20 elements were determined by INAA in leaf, soil, litter and epiphyte compartments. There was no seasonality for chemical element concentrations in leaves, which probably indicated the maintenance of chemical elements in this compartment. Considering the estimated quantities, past deforestation events could have released large amounts of chemical elements to the environment. (author)

  14. Linking neuroethology to the chemical biology of natural products

    DEFF Research Database (Denmark)

    Olivera, Baldomero M.; Raghuraman, Shrinivasan; Schmidt, Eric W.

    2017-01-01

    From a biological perspective, a natural product can be defined as a compound evolved by an organism for chemical interactions with another organism including prey, predator, competitor, pathogen, symbiont or host. Natural products hold tremendous potential as drug leads and have been extensively...... a better understanding of the evolution, biology and biochemistry of natural products will facilitate both neuroscience and the potential for drug leads. The larger goal is to establish a new sub-discipline in the broader field of neuroethology that we refer to as “Chemical Neuroethology”, linking...... the substantial work carried out by chemists on natural products with accelerating advances in neuroethology....

  15. Effect of natural and chemical insecticides on Hyalopterus pruni and ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-06-17

    Jun 17, 2008 ... Anthmis pseudocotula and their mixtures with chemical insecticide (Malathion) on growth of ... ed the use of natural extracts of Fagonia arabica, Salix ..... Studies on the efficacy of neem products against the aphid Aphis.

  16. Effect of Natural Fermentation on the Chemical and Nutritional ...

    African Journals Online (AJOL)

    Changes in the chemical and nutritional composition of naturally fermented soy nono were studied at ambient temperature (27 ± 2oC) for 72 h. The differently fermented soy nono samples were collected at 6 h intervals and analysed for chemical, proximate and mineral composition using standard laboratory procedures.

  17. Zinc in soybeans. Chemical nature and bioavilability

    International Nuclear Information System (INIS)

    Khan, A.

    1987-01-01

    Soybeans were grown hydroponically and intrinsically labeled with 65 Zn through root absorption, stem injection and foliar application. Stem injection resulted in the greatest accumulation of 65 Zn. Regardless of the labeling technique, approximately 40-45% of the seed 65 Zn was associated with the subcellular organelles. The pattern of 65 Zn incorporation into soybeans did not change appreciably as a result of the labelling technique. The major portion of the soluble 65 Zn was either free or associated with very low molecular weight proteins, peptides, or their complexes with phytic acid rather than the major proteins of soybeans. Zinc in soybeans is ionically bound to proteins, peptides and phytic acid. Autoclaving did not affect the chemical association of zinc with soy proteins. Solubility of protein, zinc and phytic acid was studied over the pH range of 3.5-12.0. Bioavailability of zinc to rats from soybeans was lower than from casein and rats adapted to a casein basal diet absorbed more 65 Zn from both casein and soy than rats adapted to a soy basal diet

  18. Natural radiation, radioactive waste and chemical risk determinants

    International Nuclear Information System (INIS)

    Christensen, T.; Mustonen, R.; Edhwall, H.; Hansen, H.; Soerensen, A.; Stranden, E.

    1990-01-01

    Doses from natural radiation to the population in the Nordic countries are summarized, and man-made modifications of the natural radiation environment are discussed. An account is given for the radiological concequences of energy concervation by reduced ventilation. Risks from possible future releases of radioactivity from final depositories of spent nuclear fuel are compared to the risks from present natural radioactivity in the environment. The possibilities for comparison between chemical and radiological risks are discussed. 104 refs., 36 figs., 47 tabs

  19. Lactobacillus brevis strains from fermented aloe vera survive gastroduodenal environment and suppress common food borne enteropathogens.

    Science.gov (United States)

    Kim, Young-Wook; Jeong, Young-Ju; Kim, Ah-Young; Son, Hyun-Hee; Lee, Jong-Am; Jung, Cheong-Hwan; Kim, Chae-Hyun; Kim, Jaeman

    2014-01-01

    Five novel Lactobacillus brevis strains were isolated from naturally fermented Aloe vera leaf flesh. Each strain was identified by Random Amplified Polymorphic DNA (RAPD) analysis and 16S rRNA sequence comparison. These strains were highly tolerant to acid, surviving in pH2.5 for up to 4 hours, and resistant to 5% bile salts at 37°C for 18 hours. Due to its tolerance to acid and bile salts, one strain passed through the gastric barrier and colonised the intestine after oral administration. All five strains inhibited the growth of many harmful enteropathogens without restraining most of normal commensals in the gut and hence named POAL (Probiotics Originating from Aloe Leaf) strains. Additionally, each strain exhibited discriminative resistance to a wide range of antibiotics. The L. brevis POAL strains, moreover, expressed high levels of the glutamate decarboxylase (GAD) gene which produces a beneficial neurotransmitter, γ-aminobutyric acid (GABA). These characteristics in all suggest that the novel L. brevis strains should be considered as potential food additives and resources for pharmaceutical research.

  20. Lactobacillus brevis strains from fermented aloe vera survive gastroduodenal environment and suppress common food borne enteropathogens.

    Directory of Open Access Journals (Sweden)

    Young-Wook Kim

    Full Text Available Five novel Lactobacillus brevis strains were isolated from naturally fermented Aloe vera leaf flesh. Each strain was identified by Random Amplified Polymorphic DNA (RAPD analysis and 16S rRNA sequence comparison. These strains were highly tolerant to acid, surviving in pH2.5 for up to 4 hours, and resistant to 5% bile salts at 37°C for 18 hours. Due to its tolerance to acid and bile salts, one strain passed through the gastric barrier and colonised the intestine after oral administration. All five strains inhibited the growth of many harmful enteropathogens without restraining most of normal commensals in the gut and hence named POAL (Probiotics Originating from Aloe Leaf strains. Additionally, each strain exhibited discriminative resistance to a wide range of antibiotics. The L. brevis POAL strains, moreover, expressed high levels of the glutamate decarboxylase (GAD gene which produces a beneficial neurotransmitter, γ-aminobutyric acid (GABA. These characteristics in all suggest that the novel L. brevis strains should be considered as potential food additives and resources for pharmaceutical research.

  1. Study and interpretation of the chemical characteristics of natural water

    Science.gov (United States)

    Hem, John David

    1985-01-01

    The chemical composition of natural water is derived from many different sources of solutes, including gases and aerosols from the atmosphere, weathering and erosion of rocks and soil, solution or precipitation reactions occurring below the land surface, and cultural effects resulting from human activities. Broad interrelationships among these processes and their effects can be discerned by application of principles of chemical thermodynamics. Some of the processes of solution or precipitation of minerals can be closely evaluated by means of principles of chemical equilibrium, including the law of mass action and the Nernst equation. Other processes are irreversible and require consideration of reaction mechanisms and rates. The chemical composition of the crustal rocks of the Earth and the composition of the ocean and the atmosphere are significant in evaluating sources of solutes in natural freshwater.

  2. "Human Nature": Chemical Engineering Students' Ideas about Human Relationships with the Natural World

    Science.gov (United States)

    Goldman, Daphne; Assaraf, Orit Ben-Zvi; Shemesh, Julia

    2014-01-01

    While importance of environmental ethics, as a component of sustainable development, in preparing engineers is widely acknowledged, little research has addressed chemical engineers' environmental concerns. This study aimed to address this void by exploring chemical engineering students' values regarding human-nature relationships. The study was…

  3. Chemical nature of catalysts of oxide nanoparticles in environment ...

    Indian Academy of Sciences (India)

    12

    Chemical nature of catalysts of oxide nanoparticles in environment prevailing during growth of carbon nanostructures by CCVD. M. Jana*, A. Sil and S. Ray. †. Department of Metallurgical and Materials Engineering. Indian Institute of Technology Roorkee. Roorkee 247 667, India. Present address: *School of Materials ...

  4. Lactic acid production from biomass-derived sugars via co-fermentation of Lactobacillus brevis and Lactobacillus plantarum.

    Science.gov (United States)

    Zhang, Yixing; Vadlani, Praveen V

    2015-06-01

    Lignocellulosic biomass is an attractive alternative resource for producing chemicals and fuels. Xylose is the dominating sugar after hydrolysis of hemicellulose in the biomass, but most microorganisms either cannot ferment xylose or have a hierarchical sugar utilization pattern in which glucose is consumed first. To overcome this barrier, Lactobacillus brevis ATCC 367 was selected to produce lactic acid. This strain possesses a relaxed carbon catabolite repression mechanism that can use glucose and xylose simultaneously; however, lactic acid yield was only 0.52 g g(-1) from a mixture of glucose and xylose, and 5.1 g L(-1) of acetic acid and 8.3 g L(-1) of ethanol were also formed during production of lactic acid. The yield was significantly increased and ethanol production was significantly reduced if L. brevis was co-cultivated with Lactobacillus plantarum ATCC 21028. L. plantarum outcompeted L. brevis in glucose consumption, meaning that L. brevis was focused on converting xylose to lactic acid and the by-product, ethanol, was reduced due to less NADH generated in the fermentation system. Sequential co-fermentation of L. brevis and L. plantarum increased lactic acid yield to 0.80 g g(-1) from poplar hydrolyzate and increased yield to 0.78 g lactic acid per g of biomass from alkali-treated corn stover with minimum by-product formation. Efficient utilization of both cellulose and hemicellulose components of the biomass will improve overall lactic acid production and enable an economical process to produce biodegradable plastics. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  5. Chemical behaviour of transuranic elements in the natural environment

    International Nuclear Information System (INIS)

    Kim, J.I.

    1991-01-01

    The chemical behaviour of transuranic elements in natural aquifer systems is governed by a variety of geochemical reactions, such as dissolution reaction (solubility), hydrolysis, complexation with inorganics or organics, redox reaction, colloid formation, geochemical interaction with surfaces of various minerals, coprecipitation, mineralisation etc. This paper reviews the present state of knowledge on some of these particular reactions. The emphasis is placed on how the individual reactions can be appraised for the long-term prediction of the geochemical behaviour of transuranic elements in the natural environment. Of the various reactions, the primary thermodynamic processes of dissolution of transuranic compounds in aquatic solution, complexation with important anions present in groundwater and colloid generation are discussed with notable examples. Various laser spectroscopy in use for the chemical speciation are mentioned briefly as for their spectroscopic capability as well as applicability. The present review discussion is primarily directed to a better understanding of the migration behaviour of transuranic elements in natural aquifer systems. (author) 100 refs

  6. Chemical Affinity as Material Agency for Naturalizing Contextual Meaning

    Directory of Open Access Journals (Sweden)

    Koichiro Matsuno

    2012-01-01

    Full Text Available Chemical affinity involves the integration of two different types of interaction. One is the interaction operating between a pair of reactants while forming a chemical bond, and the other is the prior interaction between those reactants when they identify a reaction partner. The context of the environments under which chemical reactions proceed is identified by the interaction of the participating chemical reactants themselves unless the material process of internal measurement is substituted by theoretical artifacts in the form of imposed boundary conditions, as in the case, for example, of thermal equilibrium. The identification-interaction specific to each local participant serves as a preparation for the making of chemical bonds. The identification-interaction is intrinsically selective in precipitating those chemical bonds that are synthesized most rapidly among possible reactions. Once meta-stable products appear that mediate chemical syntheses and their partial decompositions without totally decomposing, those products would become selective because of their ongoing participation in the identification-interaction. One important natural example must have been the origin and evolution of life on Earth.

  7. EMG biofeedback of the abductor pollicis brevis in piano performance.

    Science.gov (United States)

    Montes, R; Bedmar, M; Sol Martin, M

    1993-06-01

    The aim of the present study was to apply EMG biofeedback as an auxiliary to piano teaching techniques. We studied the changes in integrated electromyographic activity, using the abductor pollicis brevis functioning as an agonist during the teaching of identical selective movements of piano playing in two groups, one with EMG biofeedback and the other following traditional method of instruction. The analysis of variance revealed an increase in the peak amplitude and the relaxation rate values for the biofeedback group. These results have implications for the application of piano playing techniques and reveal EMG biofeedback as an aid in the teaching of thumb attack with the abductor pollicis brevis as agonist.

  8. Dairy Streptococcus thermophilus improves cell viability of Lactobacillus brevis NPS-QW-145 and its γ-aminobutyric acid biosynthesis ability in milk

    OpenAIRE

    Qinglong Wu; Yee-Song Law; Nagendra P. Shah

    2015-01-01

    Most high ?-aminobutyric acid (GABA) producers are Lactobacillus brevis of plant origin, which may be not able to ferment milk well due to its poor proteolytic nature as evidenced by the absence of genes encoding extracellular proteinases in its genome. In the present study, two glutamic acid decarboxylase (GAD) genes, gadA and gadB, were found in high GABA-producing L. brevis NPS-QW-145. Co-culturing of this organism with conventional dairy starters was carried out to manufacture GABA-rich f...

  9. Cofactor engineering of Lactobacillus brevis alcohol dehydrogenase by computational design

    NARCIS (Netherlands)

    Machielsen, M.P.; Looger, L.L.; Raedts, J.G.J.; Dijkhuizen, S.; Hummel, W.; Henneman, H.G.; Daussmann, T.; Oost, van der J.

    2009-01-01

    The R-specific alcohol dehydrogenase from Lactobacillus brevis (Lb-ADH) catalyzes the enantioselective reduction of prochiral ketones to the corresponding secondary alcohols. It is stable and has broad substrate specificity. These features make this enzyme an attractive candidate for

  10. Natural Ores as Oxygen Carriers in Chemical Looping Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Hanjing; Siriwardane, Ranjani; Simonyi, Thomas; Poston, James

    2013-08-01

    Chemical looping combustion (CLC) is a combustion technology that utilizes oxygen from oxygen carriers (OC), such as metal oxides, instead of air to combust fuels. The use of natural minerals as oxygen carriers has advantages, such as lower cost and availability. Eight materials, based on copper or iron oxides, were selected for screening tests of CLC processes using coal and methane as fuels. Thermogravimetric experiments and bench-scale fixed-bed reactor tests were conducted to investigate the oxygen transfer capacity, reaction kinetics, and stability during cyclic reduction/oxidation reaction. Most natural minerals showed lower combustion capacity than pure CuO/Fe{sub 2}O{sub 3} due to low-concentrations of active oxide species in minerals. In coal CLC, chryscolla (Cu-based), magnetite, and limonite (Fe-based) demonstrated better reaction performances than other materials. The addition of steam improved the coal CLC performance when using natural ores because of the steam gasification of coal and the subsequent reaction of gaseous fuels with active oxide species in the natural ores. In methane CLC, chryscolla, hematite, and limonite demonstrated excellent reactivity and stability in 50-cycle thermogravimetric analysis tests. Fe{sub 2}O{sub 3}-based ores possess greater oxygen utilization but require an activation period before achieving full performance in methane CLC. Particle agglomeration issues associated with the application of natural ores in CLC processes were also studied by scanning electron microscopy (SEM).

  11. An electrochemical study of natural and chemically controlled eumelanin

    Directory of Open Access Journals (Sweden)

    Ri Xu

    2017-12-01

    Full Text Available Eumelanin is the most common form of the pigment melanin in the human body, with functions including antioxidant behavior, metal chelation, and free radical scavenging. This biopigment is of interest for biologically derived batteries and supercapacitors. In this work, we characterized the voltammetric properties of chemically controlled eumelanins produced from 5,6-dihydroxyindole (DHI and 5,6-dihydroxyindole-2-carboxylic acid (DHICA building blocks, namely, DHI-melanin, DHICA-melanin, and natural eumelanin, extracted from the ink sac of cuttlefish, Sepia melanin. Eumelanin electrodes were studied for their cyclic voltammetric properties in acidic buffers including Na+, K+, NH4+, and Cu2+ ions.

  12. An electrochemical study of natural and chemically controlled eumelanin

    Science.gov (United States)

    Xu, Ri; Prontera, Carmela Tania; Di Mauro, Eduardo; Pezzella, Alessandro; Soavi, Francesca; Santato, Clara

    2017-12-01

    Eumelanin is the most common form of the pigment melanin in the human body, with functions including antioxidant behavior, metal chelation, and free radical scavenging. This biopigment is of interest for biologically derived batteries and supercapacitors. In this work, we characterized the voltammetric properties of chemically controlled eumelanins produced from 5,6-dihydroxyindole (DHI) and 5,6-dihydroxyindole-2-carboxylic acid (DHICA) building blocks, namely, DHI-melanin, DHICA-melanin, and natural eumelanin, extracted from the ink sac of cuttlefish, Sepia melanin. Eumelanin electrodes were studied for their cyclic voltammetric properties in acidic buffers including Na+, K+, NH4+, and Cu2+ ions.

  13. High γ-aminobutyric acid production from lactic acid bacteria: Emphasis on Lactobacillus brevis as a functional dairy starter.

    Science.gov (United States)

    Wu, Qinglong; Shah, Nagendra P

    2017-11-22

    γ-Aminobutyric acid (GABA) and GABA-rich foods have shown anti-hypertensive and anti-depressant activities as the major functions in humans and animals. Hence, high GABA-producing lactic acid bacteria (LAB) could be used as functional starters for manufacturing novel fermented dairy foods. Glutamic acid decarboxylases (GADs) from LAB are highly conserved at the species level based on the phylogenetic tree of GADs from LAB. Moreover, two functionally distinct GADs and one intact gad operon were observed in all the completely sequenced Lactobacillus brevis strains suggesting its common capability to synthesize GABA. Difficulties and strategies for the manufacture of GABA-rich fermented dairy foods have been discussed and proposed, respectively. In addition, a genetic survey on the sequenced LAB strains demonstrated the absence of cell envelope proteinases in the majority of LAB including Lb. brevis, which diminishes their cell viabilities in milk environments due to their non-proteolytic nature. Thus, several strategies have been proposed to overcome the non-proteolytic nature of Lb. brevis in order to produce GABA-rich dairy foods.

  14. Natural mineral waters: chemical characteristics and health effects

    Science.gov (United States)

    Quattrini, Sara; Pampaloni, Barbara; Brandi, Maria Luisa

    2016-01-01

    Summary Water contributes significantly to health and a daily intake of 1.5 to 2 liters of water should be guaranteed, because a good hydration is essential to maintain the body water equilibrium, although needs may vary among people. However, worldwide population is far from the Recommended Allowance for water intake. Among the waters for human uses, there are ‘waters (treated or not), intended for drinking, used for the food and beverages preparation or for other domestic purposes’ and natural mineral waters, that are ‘originated from an aquifer or underground reservoir, spring from one or more natural or bore sources and have specific hygienic features and, eventually, healthy properties’. According to the European Legislation (2009/54/EC Directive), physical and chemical characterization is used to make a classification of the different mineral waters, basing on the analysis of main parameters. Mineral composition enables to classify natural mineral waters as bicarbonate mineral waters, sulphate mineral waters, chloride mineral waters, calcic mineral waters, magnesiac mineral waters, fluorurate mineral waters, ferrous mineral waters and sodium-rich mineral waters. Although the concerns about bottled mineral waters (due to plasticizers and endocrine disruptors), many are the health effects of natural mineral waters and several studies explored their properties and their role in different physiological and pathological conditions. PMID:28228777

  15. Modulation of the host response by probiotic Lactobacillus brevis CD2 in experimental gingivitis.

    Science.gov (United States)

    Lee, J-K; Kim, S-J; Ko, S-H; Ouwehand, A C; Ma, D S

    2015-09-01

    Probiotic Lactobacillus brevisCD2 (CD2) exerts anti-inflammatory properties by preventing nitric oxide synthesis. It is hypothesized that oral application of CD2 can inhibit naturally occurring gingival inflammation. Thirty-four healthy adults were randomized to receive L. brevisCD2 lozenges or placebo, three times daily for 14 days. The subjects refrained from oral hygiene, the extent of which was determined at various time points. In both groups, bleeding on probing scores increased continuously throughout the study except on day 3. In the placebo group, scores increased significantly from 9.50 at baseline to 14.75 and 14.81 on days 10 and 14, respectively (P gingival indices increased from baseline in both treatment groups, but no intergroup differences were observed. Measurements of immune markers in gingival crevicular fluid revealed increased production of nitric oxide in the placebo group (P gingivitis development in this model by downregulating an inflammatory cascade. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. `Human nature': Chemical engineering students' ideas about human relationships with the natural world

    Science.gov (United States)

    Goldman, Daphne; Ben-Zvi Assaraf, Orit; Shemesh, Julia

    2014-05-01

    While importance of environmental ethics, as a component of sustainable development, in preparing engineers is widely acknowledged, little research has addressed chemical engineers' environmental concerns. This study aimed to address this void by exploring chemical engineering students' values regarding human-nature relationships. The study was conducted with 247 3rd-4th year chemical engineering students in Israeli Universities. It employed the New Ecological Paradigm (NEP)-questionnaire to which students added written explanations. Quantitative analysis of NEP-scale results shows that the students demonstrated moderately ecocentric orientation. Explanations to the NEP-items reveal diverse, ambivalent ideas regarding the notions embodied in the NEP, strong scientific orientation and reliance on technology for addressing environmental challenges. Endorsing sustainability implies that today's engineers be equipped with an ecological perspective. The capacity of Higher Education to enable engineers to develop dispositions about human-nature interrelationships requires adaptation of curricula towards multidisciplinary, integrative learning addressing social-political-economic-ethical perspectives, and implementing critical-thinking within the socio-scientific issues pedagogical approach.

  17. Dairy Streptococcus thermophilus improves cell viability of Lactobacillus brevis NPS-QW-145 and its γ-aminobutyric acid biosynthesis ability in milk

    Science.gov (United States)

    Wu, Qinglong; Law, Yee-Song; Shah, Nagendra P.

    2015-01-01

    Most high γ-aminobutyric acid (GABA) producers are Lactobacillus brevis of plant origin, which may be not able to ferment milk well due to its poor proteolytic nature as evidenced by the absence of genes encoding extracellular proteinases in its genome. In the present study, two glutamic acid decarboxylase (GAD) genes, gadA and gadB, were found in high GABA-producing L. brevis NPS-QW-145. Co-culturing of this organism with conventional dairy starters was carried out to manufacture GABA-rich fermented milk. It was observed that all the selected strains of Streptococcus thermophilus, but not Lactobacillus delbrueckii subsp. bulgaricus, improved the viability of L. brevis NPS-QW-145 in milk. Only certain strains of S. thermophilus improved the gadA mRNA level in L. brevis NPS-QW-145, thus enhanced GABA biosynthesis by the latter. These results suggest that certain S. thermophilus strains are highly recommended to co-culture with high GABA producer for manufacturing GABA-rich fermented milk. PMID:26245488

  18. Dairy Streptococcus thermophilus improves cell viability of Lactobacillus brevis NPS-QW-145 and its γ-aminobutyric acid biosynthesis ability in milk.

    Science.gov (United States)

    Wu, Qinglong; Law, Yee-Song; Shah, Nagendra P

    2015-08-06

    Most high γ-aminobutyric acid (GABA) producers are Lactobacillus brevis of plant origin, which may be not able to ferment milk well due to its poor proteolytic nature as evidenced by the absence of genes encoding extracellular proteinases in its genome. In the present study, two glutamic acid decarboxylase (GAD) genes, gadA and gadB, were found in high GABA-producing L. brevis NPS-QW-145. Co-culturing of this organism with conventional dairy starters was carried out to manufacture GABA-rich fermented milk. It was observed that all the selected strains of Streptococcus thermophilus, but not Lactobacillus delbrueckii subsp. bulgaricus, improved the viability of L. brevis NPS-QW-145 in milk. Only certain strains of S. thermophilus improved the gadA mRNA level in L. brevis NPS-QW-145, thus enhanced GABA biosynthesis by the latter. These results suggest that certain S. thermophilus strains are highly recommended to co-culture with high GABA producer for manufacturing GABA-rich fermented milk.

  19. Exploring the Potential for Using Inexpensive Natural Reagents Extracted from Plants to Teach Chemical Analysis

    Science.gov (United States)

    Hartwell, Supaporn Kradtap

    2012-01-01

    A number of scientific articles report on the use of natural extracts from plants as chemical reagents, where the main objective is to present the scientific applications of those natural plant extracts. The author suggests that natural reagents extracted from plants can be used as alternative low cost tools in teaching chemical analysis,…

  20. Mechanical properties of uniaxial natural fabric Grewia tilifolia reinforced epoxy based composites: Effects of chemical treatment

    CSIR Research Space (South Africa)

    Jayaramudu, J

    2014-07-01

    Full Text Available The effects of chemical treatment on the mechanical, morphological, and chemical resistance properties of uniaxial natural fabrics, Grewia tilifolia/epoxy composites, were studied. In order to enhance the interfacial bonding between the epoxy matrix...

  1. The costs of respiratory illnesses arising from Florida gulf coast Karenia brevis blooms.

    Science.gov (United States)

    Hoagland, Porter; Jin, Di; Polansky, Lara Y; Kirkpatrick, Barbara; Kirkpatrick, Gary; Fleming, Lora E; Reich, Andrew; Watkins, Sharon M; Ullmann, Steven G; Backer, Lorraine C

    2009-08-01

    Algal blooms of Karenia brevis, a harmful marine algae, occur almost annually off the west coast of Florida. At high concentrations, K. brevis blooms can cause harm through the release of potent toxins, known as brevetoxins, to the atmosphere. Epidemiologic studies suggest that aerosolized brevetoxins are linked to respiratory illnesses in humans. We hypothesized a relationship between K. brevis blooms and respiratory illness visits to hospital emergency departments (EDs) while controlling for environmental factors, disease, and tourism. We sought to use this relationship to estimate the costs of illness associated with aerosolized brevetoxins. We developed a statistical exposure-response model to express hypotheses about the relationship between respiratory illnesses and bloom events. We estimated the model with data on ED visits, K. brevis cell densities, and measures of pollen, pollutants, respiratory disease, and intra-annual population changes. We found that lagged K. brevis cell counts, low air temperatures, influenza outbreaks, high pollen counts, and tourist visits helped explain the number of respiratory-specific ED diagnoses. The capitalized estimated marginal costs of illness for ED respiratory illnesses associated with K. brevis blooms in Sarasota County, Florida, alone ranged from $0.5 to $4 million, depending on bloom severity. Blooms of K. brevis lead to significant economic impacts. The costs of illness of ED visits are a conservative estimate of the total economic impacts. It will become increasingly necessary to understand the scale of the economic losses associated with K. brevis blooms to make rational choices about appropriate mitigation.

  2. Membrane-bound ATPase contributes to hop resistance of Lactobacillus brevis

    NARCIS (Netherlands)

    Sakamoto, K; van Veen, HW; Saito, H; Kobayashi, H; Konings, WN

    2002-01-01

    The activity of the membrane-bound H+-ATPase of the beer spoilage bacterium Lactobacillus brevis ABBC45 increased upon adaptation to bacteriostatic hop compounds. The ATPase activity was optimal around pH 5.6 and increased up to fourfold when L. brevis was exposed to 666 muM hop compounds. The

  3. FATTY ACID AND STEROL COMPOSITION OF A KARENIA BREVIS BLOOM IN THE GULF OF MEXICO

    Science.gov (United States)

    In the Gulf of Mexico, recurring algal blooms, caused by Karenia brevis (formerly known as Gymnodinium breve), have significant adverse health and economic impacts. K. brevis is one member of a small group of dinoflagellates, related morphologically and by DNA-based phylogenetic ...

  4. Relative Configuration of Natural Products Using NMR Chemical Shifts

    Science.gov (United States)

    By comparing calculated with experimental NMR chemical shifts, we were able to determine the relative configurations of three monoterpene diastereomers produced by the walkingstick Anisomorpha buprestoides. The combined RMSDs of both 1H and 13C quantum chemically calculated shifts were able to predi...

  5. Effects of Karenia brevis on clearance rates and bioaccumulation of brevetoxins in benthic suspension feeding invertebrates.

    Science.gov (United States)

    Echevarria, Michael; Naar, Jerome P; Tomas, Carmelo; Pawlik, Joseph R

    2012-01-15

    Blooms of the toxic alga Karenia brevis occur along coastlines where sessile suspension feeding invertebrates are common components of benthic communities. We studied the effects of K. brevis on four benthic suspension feeding invertebrates common to the coast of the SE United States: the sponge Haliclona tubifera, the bryozoan Bugula neritina, the bivalve Mercenaria mercenaria, and the tunicate Styela plicata. In controlled laboratory experiments, we determined the rate at which K. brevis was cleared from the seawater by these invertebrates, the effect of K. brevis on clearance rates of a non-toxic phytoplankton species, Rhodomonas sp., and the extent to which brevetoxins bioaccumulated in tissues of invertebrates using an enzyme-linked immunosorbent assay (ELISA). All four invertebrate species cleared significant quantities of K. brevis from seawater, with mean clearance rates ranging from 2.27 to 6.71 L g h⁻¹ for H. tubifera and S. plicata, respectively. In the presence of K. brevis, clearance rates of Rhodomonas sp. by B. neritina and S. plicata were depressed by 75% and 69%, respectively, while clearance rates by H. tubifera and M. mercenaria were unaffected. Negative effects of K. brevis were impermanent; after a recovery period of 13 h, B. neritina and S. plicata regained normal clearance rates. All four invertebrates accumulated high concentrations of brevetoxin after a 4h exposure to K. brevis, but when animals were transferred to filtered seawater for 15 h after exposure, brevetoxin concentrations in the tissues of H. tubifera and B. neritina decreased by ∼80%, while there was no change in toxin concentration in the tissues of S. plicata and M. mercenaria. High cell concentrations of K. brevis may cause a suppression of clearance rates in benthic suspension feeding invertebrates, resulting in a positive feedback for bloom formation. Also, high concentrations of toxin may accumulate in the tissues of benthic suspension feeding invertebrates that may

  6. Natural Attenuation of the Persistent Chemical Warfare Agent ...

    Science.gov (United States)

    Report This project studied the influence of temperature on the natural attenuation of VX from five types of porous/permeable materials: unsealed concrete, plywood, rubber escalator handrail, high density polyethylene (HDPE) plastic, and acoustic ceiling tile.

  7. Effect of natural and chemical insecticides on Hyalopterus pruni and ...

    African Journals Online (AJOL)

    Experiments were carried out to evaluate the effect of water extracts of Fagonia arabica, Salix alba and Anthmis pseudocotula and their mixtures with chemical insecticide (Malathion) on growth of. Hyalopterus pruni and characters of Armeniaca vulgaris plants and their soils. The data revealed that F.arabica extract at 20% ...

  8. Chemical nature of catalysts of oxide nanoparticles in environment

    Indian Academy of Sciences (India)

    Carbon nanostructures (CNS) are often grown using oxide nanoparticles as catalyst in chemical vapour deposition and these oxides are not expected to survive as such during growth. In the present study, the catalysts of cobalt- and nickel oxide-based nanoparticles of sizes varying over a range have been reduced at 575 ...

  9. Mutagenesis breeding research of Lactobacillus brevis of nitrite reduction

    Directory of Open Access Journals (Sweden)

    LI Zeli

    2015-10-01

    Full Text Available The pollution of nitrite in food became one of the focus of food safety issues,the use of biotechnology methods degrading nitrite became hotspot.The primitive strain was Lactobacillus brevis C2,preserved in our laboratory,had the ability to degrade nitrite,through composite mutagenesis of 15 W,254 nm,20 cm ultraviolet mutagenesis (UV for 120 s and 0.8% diethyl sulfate(DES in 37℃ mutation for 40 min,after screening,we successfully obtained high efficient strain of nitrite degradation,named UV6-DS2,relative to the starting strain,under the condition of 400 mg/L nitrite,after 12 h degradation,nitrite degradation rate increased from 92.8% to 97.8%,to explore its application in food was able to effectively reduce concentration of nitrite in food.

  10. Chemical Interactions of Hydraulic Fracturing Biocides with Natural Pyrite

    Science.gov (United States)

    Consolazio, Nizette A.

    In conjunction with horizontal drilling, hydraulic fracturing or fracking has enabled the recovery of natural gas from low permeable shale formations. In addition to water, these fracking fluids employ proppants and up to 38 different chemical additives to improve the efficiency of the process. One important class of additives used in hydraulic fracturing is biocides. When applied appropriately, they limit the growth of harmful microorganisms within the well, saving energy producers 4.5 billion dollars each year. However, biocides or their harmful daughter products may return to the surface in produced water, which must then be appropriately stored, treated and disposed of. Little is known about the effect of mineral-fluid interactions on the fate of the biocides employed in hydraulic fracturing. In this study, we employed laboratory experiments to determine changes in the persistence and products of these biocides under controlled environments. While many minerals are present in shale formations, pyrite, FeS2(s) is particularly interesting because of its prevalence and reactivity. The FeII groups on the face of pyrite may be oxidized to form FeIII phases. Both of these surfaces have been shown to be reactive with organic compounds. Chlorinated compounds undergo redox reactions at the pyrite-fluid interface, and sulfur-containing compounds undergo exceptionally strong sorption to both pristine and oxidized pyrite. This mineral may significantly influence the degradation of biocides in the Marcellus Shale. Thus, the overall goal of this study was to understand the effect of pyrite on biocide reactivity in hydraulic fracturing, focusing on the influence of pyrite on specific functional groups. The first specific objective was to demonstrate the effect of pyrite and pyrite reaction products on the degradation of the bromine-containing biocide, DBNPA. On the addition of pyrite to DBNPA, degradation rates of the doubly brominated compound were found to increase

  11. Isotopic composition of chemical elements in natural cycles

    International Nuclear Information System (INIS)

    Wetzel, K.

    1977-12-01

    Mathematical models developed for planning and evaluating tracer experiments have been applied in investigations of the isotopic composition of carbon in its natural cycle through various periods of the last billion years. The influence on the natural isotope ratio due to industrial combustion of fossil fuels is shown. In order to describe regional differences from the global behaviour of carbon a parameter has been introduced, which represents the time needed for one total exchange of the atmosphere in a certain region with the global atmosphere

  12. Chemical and structural characterization of natural phosphate of ...

    African Journals Online (AJOL)

    Powder X-ray diffraction fitting results confirm that compound belongs to the apatite family crystallising in the hexagonal system, space group P63/m. The cell parameters are: a = 9.3547(5) Å; c = 6.8929(4) Å. KEY WORDS: Natural phosphate, Fluoroapatite, Infrared, X-Ray diffraction, Rietveld structure refinement. Bull. Chem ...

  13. PERFORMANCE IMPROVEMENT OF A CHEMICAL REACTOR BY NONLINEAR NATURAL OSCILLATIONS

    NARCIS (Netherlands)

    RAY, AK

    1995-01-01

    The dynamic behaviour of two coupled continuous stirred tank reactors in sequence is studied when the first reactor is being operated under limit cycle regimes producing self-sustained natural oscillations. The periodic output from the first reactor is then used as a forced input into the second

  14. Chemical nature and distribution of calcium compounds in radiolucent gallstones

    International Nuclear Information System (INIS)

    Agarwal, D.K.; Choudhuri, G.; Kumar, J.

    1993-01-01

    A high failure rate for radiolucent cholesterol gallstones to dissolve with oral bile acids may be due to the presence of insoluble calcium compounds. Twenty sets of radiolucent gallstones, 7-20 mm in diameter, obtained from 20 patients undergoing cholecystectomy, were cut, and the outer surface, outer rim, middle portion, and central core areas were scanned for calcium by energy-dispersive X-ray microanalysis (EDX) and scanning electron microscopy (SEM). Scrapings from the four areas of each stone were analysed by infrared spectroscopy. A sample of the crushed stone was used for chemical estimation of cholesterol. 11 of the 20 cholesterol stones showed presence of calcium by EDX; the distribution was peripheral in 5, homogeneous in 4, and central in 2. The chemical compound was calcium bilirubinate in 10 and calcium carbonate in 8 stones. Calcium compounds are present in a high proportion of radiolucent gallstones considered suitable for chemodissolution by conventional criteria. Their unrecognized presence may explain the high failure rate of such stones to respond to medical therapy. 20 refs., 3 figs

  15. Comparative analysis of chemical similarity methods for modular natural products with a hypothetical structure enumeration algorithm.

    Science.gov (United States)

    Skinnider, Michael A; Dejong, Chris A; Franczak, Brian C; McNicholas, Paul D; Magarvey, Nathan A

    2017-08-16

    Natural products represent a prominent source of pharmaceutically and industrially important agents. Calculating the chemical similarity of two molecules is a central task in cheminformatics, with applications at multiple stages of the drug discovery pipeline. Quantifying the similarity of natural products is a particularly important problem, as the biological activities of these molecules have been extensively optimized by natural selection. The large and structurally complex scaffolds of natural products distinguish their physical and chemical properties from those of synthetic compounds. However, no analysis of the performance of existing methods for molecular similarity calculation specific to natural products has been reported to date. Here, we present LEMONS, an algorithm for the enumeration of hypothetical modular natural product structures. We leverage this algorithm to conduct a comparative analysis of molecular similarity methods within the unique chemical space occupied by modular natural products using controlled synthetic data, and comprehensively investigate the impact of diverse biosynthetic parameters on similarity search. We additionally investigate a recently described algorithm for natural product retrobiosynthesis and alignment, and find that when rule-based retrobiosynthesis can be applied, this approach outperforms conventional two-dimensional fingerprints, suggesting it may represent a valuable approach for the targeted exploration of natural product chemical space and microbial genome mining. Our open-source algorithm is an extensible method of enumerating hypothetical natural product structures with diverse potential applications in bioinformatics.

  16. Isolation of plutonium physical--chemical states from natural waters

    International Nuclear Information System (INIS)

    Weimer, W.C.

    1978-08-01

    The purpose of this research program was to evaluate the feasibility, on a bench scale, of methods for preconcentrating selectively individual plutonium forms from very dilute natural water samples, and to apply these results to use with the Battelle large volume water sampler. From the results of the current investigations, several alternative water sampling strategies have been recommended. The preferred water sampling technique has been field tested at several groundwater wells in the 200 East and 200 West areas of the U.S. Department of Energy Hanford Reservation. These laboratory investigations, in combination with field testing of the proposed water sampling techniques, have yielded the following conclusions: (1) The use of polypropylene microporous filters (0.04μ pore size) in conjunction with glass fiber filters (3.0μ pore size) enables the characterization of two size fractions of particulate plutonium forms in groundwater samples. Those species which pass the microporous polypropylene filters are considered to be in solution. (2) The sorption and ion exchange media evaluated do not show the selectivity necessary to allow preconcentration of individual plutonium forms from natural water samples by any of these media beds under the conditions evaluated. (3) Al 2 O 3 is the most effective sorption media that was examined for removing any plutonium species from natural water samples at neutral pH values. On the basis of these investigations, a standard field testing methodology has been proposed for sampling ground waters near nuclear waste management areas. Additional laboratory evaluations of plutonium species interactions with sorption and ion exchange media have also been recommended

  17. Restoration of GABA production machinery in Lactobacillus brevis by accessible carbohydrates, anaerobiosis and early acidification.

    Science.gov (United States)

    Wu, Qinglong; Shah, Nagendra P

    2018-02-01

    Lactobacillus brevis is an efficient cell factory for producing bioactive γ-aminobutyric acid (GABA) by its gad operon-encoded glutamic acid decarboxylase (GAD) system. However, little mechanistic insights have been reported on the effects of carbohydrate, oxygen and early acidification on GABA production machinery in Lb. brevis. In the present study, GABA production from Lb. brevis was enhanced by accessible carbohydrates. Fast growth of this organism was stimulated by maltose and xylose. However, its GABA production was highly suppressed by oxygen exposure, but was fully restored by anaerobiosis that up-regulated the expression of gad operon in Lb. brevis cells. Although the level of cytosolic acidity was suitable for the functioning of GadA and GadB, early acidification of the medium (ipH 5 and ipH 4) restored GABA synthesis strictly in aerated cells of Lb. brevis because the expression of gad operon was not up-regulated in them. We conclude that GABA production machinery in Lb. brevis could be restored by accessible carbohydrates, anaerobiosis and early acidification. This will be of interest for controlling fermentation for synthesis of GABA and manufacturing GABA-rich fermented vegetables. Copyright © 2017. Published by Elsevier Ltd.

  18. Understanding the triple nature of the chemical bond on submicroscopic level

    OpenAIRE

    Klun, Tina

    2017-01-01

    The master’s thesis addresses three definitions of chemical bond with particular emphasis on the sub-microscopic level in a comprehensive manner. Slovenian pupils are taught about chemical bond for the first time in the eighth grade of primary school as part of learning about the connection between particles. Due to the abstract nature of the notion chemical bond, it is essential that pupils are encouraged to learn about the topic on the macroscopic, sub microscopic and symbolic level as this...

  19. Nature of chemical bond through positron angular correlation

    International Nuclear Information System (INIS)

    Ramasamy, S.; Nagarajan, T.

    1979-01-01

    Two photon angular distribution of positron annihilation is measured for compounds (1) m- and (2) p-nitroanilines, (3) m- and (4) p-methylsulphonyl-N, N-dimethylanilines and (5) p-phenylthio- and (6) p-phenoxyanilines in order to investigate the phenomenon of resonance and the involvement of d-orbitals of sulphur in chemical bonding. The FWHM is the same (10.8 mrad) for compounds (1) and (2) indicating that the resonance in the p-isomer does not change the annihilation characteristic much. The measured FWHM (9.4 mrad) for compound (4) is much broader than that of compound (3) (FWHM = 7.7 mrad). In the case of p-isomer, there is the involvement of d-orbitals of sulphur in bond formation. FWHM for compounds (5) and (6) are almost same (8.4 mrad). In this pair the only difference is that the sulphur in one case is replaced by oxygen in the other. Since there is not enough scope for excess electrons to be accomodated at oxygen or sulphur, there is no preferential annihilation of positron at these centres. (auth.)

  20. Molecular mechanisms behind the antimicrobial activity of hop iso-α-acids in Lactobacillus brevis.

    Science.gov (United States)

    Schurr, Benjamin C; Hahne, Hannes; Kuster, Bernhard; Behr, Jürgen; Vogel, Rudi F

    2015-04-01

    The main bittering component in beer, hop iso-α-acids, have been characterised as weak acids, which act as ionophores impairing microbial cells' function under acidic conditions as present in beer. Besides medium pH, divalent cations play a central role regarding the efficacy of the antimicrobial effect. The iso-α-acids' non-bitter derivatives humulinic acids can be found in isomerised hop extracts and can be generated during hop storage. Therefore, they have been under investigation concerning their influence on beer sensory properties. This study sketches the molecular mechanism behind iso-α-acids' antimicrobial activity in Lactobacillus (L.) brevis regarding their ionophore activity versus the dependence of the inhibitory potential on manganese binding, and suggests humulinic acids as novel tasteless food preservatives. We designed and synthesised chemically modified iso-α-acids to enhance the basic understanding of the molecular mechanism of antimicrobial iso-α-acids. It could be observed that a manganese-binding dependent transmembrane redox reaction (oxidative stress) plays a crucial role in inhibition. Privation of an acidic hydroxyl group neither erased ionophore activity, nor did it entirely abolish antimicrobial activity. Humulinic acids proved to be highly inhibitory, even outperforming iso-α-acids. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Chemical speciation and adsorption behavior of plutonium in natural waters

    International Nuclear Information System (INIS)

    Sanchez, A.L.

    1983-01-01

    Dissolved Pu profiles in two partially anoxic basins--Saanich Inlet, an intermittently anoxic marine fiord in Vancouver Island, British Columbia, and Soap Lake, a saline, alkaline lake in eastern Washington state, revealed minimum concentrations at the O 2 /H 2 S interface. The Pu concentrations in the anoxic waters of Saanich Inlet were less than the surface concentrations; however, in Soap Lake, a 15- to 50-fold increase in Pu concentration in the anoxic monimolimnion correlated with large increases in the major ions, total alkalinity, and dissolved organic carbon. Laboratory experiments were designed to investigate the effects of pH, ionic strength, dissolved organic carbon, and carbonate ions on the adsorption of tracer amounts of Pu IV and Pu V. The Pu-goethite adsorption system provided the data base for developing a thermodynamic model of Pu interaction with an oxide surface and with dissolved ligands, using the MINEQL computer program. Pu IV and Pu V interacted very differently with goethite, which is consistent with their different hydrolytic character. A reduction of Pu V to Pu IV occurred on the goethite surface and also on montmorillonite and silica gel, suggesting that redox transformations are an important aspect of Pu adsorption. Increases in ionic strength (up to 3 M NaCl or NaNO 3 ) did not affect Pu IV or V adsorption. In the presence of dissolved organic carbon (DOC), Pu V reduction to Pu IV occurred in solution. Pu IV adsorption on goethite decreased only 30% in the presence of 240 ppm of natural DOC from Soap Lake; however, carbonate anions inhibited Pu IV adsorption on goethite at the alkalinity levels (1500 meq/L total alkalinity, 0.57 M CO 3 =) measured for Soap Lake monimolimnion waters

  2. Chemically reduced graphene contains inherent metallic impurities present in parent natural and synthetic graphite

    Science.gov (United States)

    Ambrosi, Adriano; Chua, Chun Kiang; Khezri, Bahareh; Sofer, Zdeněk; Webster, Richard D.; Pumera, Martin

    2012-01-01

    Graphene-related materials are in the forefront of nanomaterial research. One of the most common ways to prepare graphenes is to oxidize graphite (natural or synthetic) to graphite oxide and exfoliate it to graphene oxide with consequent chemical reduction to chemically reduced graphene. Here, we show that both natural and synthetic graphite contain a large amount of metallic impurities that persist in the samples of graphite oxide after the oxidative treatment, and chemically reduced graphene after the chemical reduction. We demonstrate that, despite a substantial elimination during the oxidative treatment of graphite samples, a significant amount of impurities associated to the chemically reduced graphene materials still remain and alter their electrochemical properties dramatically. We propose a method for the purification of graphenes based on thermal treatment at 1,000 °C in chlorine atmosphere to reduce the effect of such impurities on the electrochemical properties. Our findings have important implications on the whole field of graphene research. PMID:22826262

  3. Chemically reduced graphene contains inherent metallic impurities present in parent natural and synthetic graphite.

    Science.gov (United States)

    Ambrosi, Adriano; Chua, Chun Kiang; Khezri, Bahareh; Sofer, Zdeněk; Webster, Richard D; Pumera, Martin

    2012-08-07

    Graphene-related materials are in the forefront of nanomaterial research. One of the most common ways to prepare graphenes is to oxidize graphite (natural or synthetic) to graphite oxide and exfoliate it to graphene oxide with consequent chemical reduction to chemically reduced graphene. Here, we show that both natural and synthetic graphite contain a large amount of metallic impurities that persist in the samples of graphite oxide after the oxidative treatment, and chemically reduced graphene after the chemical reduction. We demonstrate that, despite a substantial elimination during the oxidative treatment of graphite samples, a significant amount of impurities associated to the chemically reduced graphene materials still remain and alter their electrochemical properties dramatically. We propose a method for the purification of graphenes based on thermal treatment at 1,000 °C in chlorine atmosphere to reduce the effect of such impurities on the electrochemical properties. Our findings have important implications on the whole field of graphene research.

  4. Studies of linear Gramicidin synthesis in Bacillus brevis ATCC 8185

    International Nuclear Information System (INIS)

    Kubota, Kou; Kagawa, Kenichi

    1976-01-01

    Bacillus brevis ATCC 8185 was grown in polypepton and Ehrlich's meat extract medium, and this strain produced two kinds of peptide antibiotics, Tyrocidine and linear Gramicidin. A simple chromatographic method was developed for the isolation of linear Gramicidin from mixture Tyrothricin, applied on the column. Trimethoprim, an inhibitor of dihydrofolate reductase, inhibits the synthesis of both peptides in the growing culture with slight inhibition to cell growth. Serine- 14 C is incorporated in the Gramicidin, and recovered as ethanol amine and glycine by the hydrolysis of 14 C-labeled Gramicidin, but deoxypyridoxine-HCl, B 6 antagonist, has no effect on the production of antibiotics in the culture. Linear Gramicidin gives two spots on the thin layer chromatogram (TLC) developed by ethyl acetate-pyridine-water system of 16:4:2, and by chloroform-methanol-water system of 17:3:0.3. The incorporations of constitutive 14 C-labeled amino acids, ethanol amine, and sodium formate into linear Gramicidin were studied by growing cells. These labeled specimens were identified to correspond to authentic specimens which migrated on TLC. Cells were hydrolysed with Lysozyme, and the crude extract was prepared between 0.33 and 0.45 saturation of ammonium sulfate. It activated constituent amino acids including D-leucine by ATP- 32 PPi exchange reaction, but hardly activated L-serine, D-valine, and formyl L-valine. (Kobatake, H.)

  5. Purification and biochemical characterization of a highly thermostable bacteriocin isolated from Brevibacillus brevis strain GM100.

    Science.gov (United States)

    Ghadbane, Mouloud; Harzallah, Daoud; Laribi, Atef Ibn; Jaouadi, Bassem; Belhadj, Hani

    2013-01-01

    A bacteriocin-producing (11,000 AU mL(-1)) strain was isolated from the rhizosphere of healthy Algerian plants Ononis angustissima Lam., and identified as Brevibacillus brevis strain GM100. The bacteriocin, called Bac-GM100, was purified to homogeneity from the culture supernatant, and, based on MALDI-TOF/MS analysis, was a monomer protein with a molecular mass of 4375.66 Da. The 21 N-terminal residues of Bac-GM100 displayed 65% homology with thurincin H from Bacillus thuringiensis. Bac-GM100 was extremely heat-stable (20 min at 120 °C), and was stable within a pH range of 3-10. It proved sensitive to various proteases, which demonstrated its protein nature. It was also found to display a bactericidal mode of action against gram-negative (Salmonella enteric ATCC 43972, Pseudomonas aeruginosa ATCC 49189, and Agrobacterium tumefaciens C58) and gram-positive (Enterococcus faecalis ENSAIA 631 and Staphylococcus aureus ATCC 6538) bacteria, and a fungistatic mode of action against the pathogenic fungus Candida tropicalis R2 CIP 203.

  6. Purification process of natural graphite as anode for Li-ion batteries: chemical versus thermal

    Science.gov (United States)

    Zaghib, K.; Song, X.; Guerfi, A.; Rioux, R.; Kinoshita, K.

    The intercalation of Li ions in natural graphite that was purified by chemical and thermal processes was investigated. A new chemical process was developed that involved a mixed aqueous solution containing 30% H 2SO 4 and 30% NH xF y heated to 90 °C. The results of this process are compared to those obtained by heating the natural graphite from 1500 to 2400 °C in an inert environment (thermal process). The first-cycle coulombic efficiency of the purified natural graphite obtained by the chemical process is 91 and 84% after the thermal process at 2400 °C. Grinding the natural graphite before or after purification had no significant effect on electrochemical performance at low currents. However, grinding to a very small particle size before purification permitted optimization of the size distribution of the particles, which gives rise to a more homogenous electrode. The impurities in the graphite play a role as microabrasion agents during grinding which enhances its hardness and improves its mechanical properties. Grinding also modifies the particle morphology from a 2- to a 3-D structure (similar in shape to a potato). This potato-shaped natural graphite shows high reversible capacity at high current densities (about 90% at 1 C rate). Our analysis suggests that thermal processing is considerably more expensive than the chemical process to obtain purified natural graphite.

  7. Natural Alternatives for Chemicals Used in Histopathology Lab- A Literature Review.

    Science.gov (United States)

    Ramamoorthy, Ananthalakshmi; Ravi, Shivani; Jeddy, Nadeem; Thangavelu, Radhika; Janardhanan, Sunitha

    2016-11-01

    Histopathology lab is the place where the specimen gets processed and stained to view under microscope for interpretation. Exposure to the chemicals used in these processes cause various health hazards to the laboratory technicians, pathologists, and scientists working in the laboratory. Hence, there is a dire need to introduce healthy and bio-friendly alternatives in the field. This literature review explores the natural products and their efficiency to be used as alternatives for chemicals in the histopathology lab.

  8. Optimization of biosurfactant production by Bacillus brevis using response surface methodology

    Directory of Open Access Journals (Sweden)

    Foukia E. Mouafi

    2016-03-01

    Full Text Available The present study aims to evaluate and validate a statistical model for maximizing biosurfactant productivity by Bacillus brevis using response surface methodology. In this respect, twenty bacterial isolates were screened for biosurfactant production using hemolytic activity, oil spreading technique, and emulsification index (E24. The most potent biosurfactant-producing bacterium (B. brevis was used for construction of the statistical response surface model. The optimum conditions for biosurfactant production by B. brevis were: 33 °C incubation temperature at pH 8 for 10 days incubation period and 8.5 g/L glucose concentration as a sole carbon source. The produced biosurfactant (BS (73% exhibited foaming activity, thermal stability in the range 30–80 °C for 30 min., pH stability, from 4 to 9 and antimicrobial activity against (Escherichia coli. The BS gave a good potential application as an emulsifier.

  9. Empedobacter brevis Meningitis in a Neonate: A Very Rare Case of Neonatal Meningitis and Literature Review

    Directory of Open Access Journals (Sweden)

    Deepak Sharma

    2016-01-01

    Full Text Available Empedobacter brevis is gram-negative bacilli that belongs to Flavobacteriaceae family. It was previously known with name of Flavobacterium breve. The reservoir of these bacteria is soil, plants, water, food, hospital water sources, including incubators, sinks, faucets, tap water, hemodialysis systems, saline solutions, and other pharmaceutical solutions. We report a case of term female newborn, admitted with complaint of respiratory distress developing soon after birth and developed clinical features of sepsis at age of 92 hours of postnatal life. The sepsis screen was positive and blood culture and cerebrospinal fluid showed growth of Empedobacter brevis that was resistant to multiple antibiotics. The neonate was treated with appropriate antibiotics and was discharged successfully. The novelty of the case report is that this is the first case report of neonatal sepsis caused by Empedobacter brevis.

  10. Reproductive Ecology of Prochilodus brevis an Endemic Fish from the Semiarid Region of Brazil

    Directory of Open Access Journals (Sweden)

    Liliane de Lima Gurgel

    2012-01-01

    Full Text Available The commercially important migratory fish Prochilodus brevis is from the Neotropical region, and understanding the reproductive ecology of this potamodromous fish is essential for its conservation and management. This study investigated the length-mass relationship, sex ratio, length at first gonadal maturity, gonadal development stages, gonadosomatic index, condition factor, and reproductive period of P. brevis. Temporal distribution of rainfall, temperature, dissolved oxygen concentration, pH, and electrical conductivity of the water were related to the reproductive period of this fish. Rainfall seems to be the main environmental factor which modulates changes in limnological parameters and the timing of the spawning period of this fish. P. brevis migrates into lower reaches of the river to feed during the dry season and returns to the upper reaches during the rainy season to spawn. Inadequate facilities for migration create obstacles for spawning success of this ecologically important fish.

  11. Interactions between toxic chemicals and natural environmental factors--a meta-analysis and case studies.

    Science.gov (United States)

    Laskowski, Ryszard; Bednarska, Agnieszka J; Kramarz, Paulina E; Loureiro, Susana; Scheil, Volker; Kudłek, Joanna; Holmstrup, Martin

    2010-08-15

    The paper addresses problems arising from effects of natural environmental factors on toxicity of pollutants to organisms. Most studies on interactions between toxicants and natural factors, including those completed in the EU project NoMiracle (Novel Methods for Integrated Risk Assessment of Cumulative Stressors in Europe) described herein, showed that effects of toxic chemicals on organisms can differ vastly depending purely on external conditions. We compiled data from 61 studies on effects of temperature, moisture and dissolved oxygen on toxicity of a range of chemicals representing pesticides, polycyclic aromatic hydrocarbons, plant protection products of bacterial origin and trace metals. In 62.3% cases significant interactions (pnatural factors and chemicals were found, reaching 100% for the effect of dissolved oxygen on toxicity of waterborne chemicals. The meta-analysis of the 61 studies showed that the null hypothesis assuming no interactions between toxic chemicals and natural environmental factors should be rejected at p=2.7 x 10(-82) (truncated product method probability). In a few cases of more complex experimental designs, also second-order interactions were found, indicating that natural factors can modify interactions among chemicals. Such data emphasize the necessity of including information on natural factors and their variation in time and across geographic regions in ecological risk assessment. This can be done only if appropriate ecotoxicological test designs are used, in which test organisms are exposed to toxicants at a range of environmental conditions. We advocate designing such tests for the second-tier ecological risk assessment procedures. Copyright 2010 Elsevier B.V. All rights reserved.

  12. Assessment of Application Technology of Natural User Interfaces in the Creation of a Virtual Chemical Laboratory

    Science.gov (United States)

    Jagodzinski, Piotr; Wolski, Robert

    2015-01-01

    Natural User Interfaces (NUI) are now widely used in electronic devices such as smartphones, tablets and gaming consoles. We have tried to apply this technology in the teaching of chemistry in middle school and high school. A virtual chemical laboratory was developed in which students can simulate the performance of laboratory activities similar…

  13. Using the Socioscientific Context of Climate Change to Teach Chemical Content and the Nature of Science

    Science.gov (United States)

    Flener-Lovitt, Charity

    2014-01-01

    A thematic course called "Climate Change: Chemistry and Controversy" was developed for upper-level non-STEM students. This course used the socioscientific context of climate change to teach chemical principles and the nature of science. Students used principles of agnotology (direct study of misinformation) to debunk climate change…

  14. Study of sorption and desorption characteristics of natural and chemically modified ionexes

    International Nuclear Information System (INIS)

    Foeldesova, M.; Dillinger, P.; Lukac, P.

    2004-01-01

    The aim of this paper was give information for scientific community about not-traditionally, simply, high precise and effective radio-indicator method and possibilities its use for determination of sorption characteristics of naturals and chemically adjusted ionexes. These materials are suitable as barrier materials for water, soil and air cleaning

  15. Plant management in natural areas: balancing chemical, mechanical, and cultural control methods

    Science.gov (United States)

    Steven Manning; James. Miller

    2011-01-01

    After determining the best course of action for control of an invasive plant population, it is important to understand the variety of methods available to the integrated pest management professional. A variety of methods are now widely used in managing invasive plants in natural areas, including chemical, mechanical, and cultural control methods. Once the preferred...

  16. Natural control in cabbage root fly populations and influence of chemicals

    NARCIS (Netherlands)

    Abu Yaman, I.K.

    1960-01-01

    To facilitate studies on the natural and chemical control of Hylemya (Erioischia) brassicae (Bch.) in Holland, the bionomics and abundance of the Anthomyiid were investigated in 1959-9 in fields in which cauliflower was grown. The numbers of eggs and larvae were estimated by scrutiny of

  17. Enhancement of mechanical properties and interfacial adhesion by chemical odification of natural fibre reinforced polypropylene composites

    CSIR Research Space (South Africa)

    Erasmus, E

    2008-11-01

    Full Text Available with the polymer matrix. Therefore, the constituents need to be chemically modified to enhancing adhesion between fibre and polymer matrix. The aim of this work is to improve the interfacial adhesion between the polypropylene matrix and the natural fibre...

  18. Chemical speciation modelling of the South Terras and Madeira Abyssal Plain natural analogue sites

    International Nuclear Information System (INIS)

    Duffield, J.R.; Xu Langqui; Williams, D.R.

    1988-11-01

    The chemical speciation of uranium has been modelled using field data from the South Terras and Madeira Abyssal Plain natural analogue sites. In general, validation is good, particularly for the Abyssal Plain model. Problems regarding uranium redox couples have been highlighted as have other areas requiring further consideration for building into the thermodynamic models. (author)

  19. Natural radiation sources fabricated from potassic chemical fertilizers and application to radiation education

    International Nuclear Information System (INIS)

    Kawano, Takao

    2010-01-01

    Potassic chemical fertilizers contain potassium, a small part of which is potassium-40. Since potassium-40 is a naturally occurring radioisotope, potassic chemical fertilizers are often used for demonstrations of the existence of natural radioisotopes and radiation. To fabricate radiation sources as educational tools, the compression and formation method developed by our previous study was applied to 13 brands of commercially available chemical fertilizers containing different amounts of potassium. The suitability (size, weight, and solidness) of thus fabricated sources was examined and 12 of them were selected as easy-to-use radiation sources at radiation educational courses. The radiation strength (radiation count rate measured by a GM survey meter) and potassium content of the 12 sources were examined. It was found that the count rate was wholly proportional to the percentage of potassium, and a new educational application was proposed and discussed for understanding that the substance emitting radiation must be the potassium present in the raw fertilizers. (author)

  20. Nature's chemical signatures in human olfaction: a foodborne perspective for future biotechnology.

    Science.gov (United States)

    Dunkel, Andreas; Steinhaus, Martin; Kotthoff, Matthias; Nowak, Bettina; Krautwurst, Dietmar; Schieberle, Peter; Hofmann, Thomas

    2014-07-07

    The biocatalytic production of flavor naturals that determine chemosensory percepts of foods and beverages is an ever challenging target for academic and industrial research. Advances in chemical trace analysis and post-genomic progress at the chemistry-biology interface revealed odor qualities of nature's chemosensory entities to be defined by odorant-induced olfactory receptor activity patterns. Beyond traditional views, this review and meta-analysis now shows characteristic ratios of only about 3 to 40 genuine key odorants for each food, from a group of about 230 out of circa 10 000 food volatiles. This suggests the foodborn stimulus space has co-evolved with, and roughly match our circa 400 olfactory receptors as best natural agonists. This perspective gives insight into nature's chemical signatures of smell, provides the chemical odor codes of more than 220 food samples, and beyond addresses industrial implications for producing recombinants that fully reconstruct the natural odor signatures for use in flavors and fragrances, fully immersive interactive virtual environments, or humanoid bioelectronic noses. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Chemical concentration of a new natural spontaneously fissionable nuclide from solutions with low salt background

    International Nuclear Information System (INIS)

    Korotkin, Yu.S.; Ter-Akop'yan, G.M.; Popeko, A.G.; Drobina, T.P.; Zhuravleva, E.L.

    1982-01-01

    The results of experiments on further concentration of a new natural spontaneously fissionable nuclide, the concentrates of which form the Cheleken geothermal brines have been obtained, are presented. The conclusions are drown about the chemical nature of a new spontaneously fissionable nuclide. It is a chalcophile element which copreipitates with sulphides of copper, lead, arsenic and mercury from weakly acid solutions. The behaviour of the new nuclide in sulphide systems in many respects is similar to the behaviour of polonium, astatine and probably of bismuth. The most probable stable valence of the new nuclide varies from +1 up to +3. The data available on the chemical behaviour of the new nuclide as well as the analysis over contamination by spontaneously fissionable isotopes permit to state that the new natural spontaneously fissionable nuclide does not relate to the known isotopes

  2. Bioprospecting of Marine Invertebrates for New Natural Products — A Chemical and Zoogeographical Perspective

    Directory of Open Access Journals (Sweden)

    Ricardo Calado

    2012-08-01

    Full Text Available Bioprospecting for new marine natural products (NPs has increased significantly over the last decades, leading to an unprecedented discovery of new molecules. Marine invertebrates have been the most important source of these NPs, with researchers commonly targeting particular taxonomic groups, marine regions and/or molecules from specific chemical groups. The present review focuses on new NPs identified from marine invertebrates between 2000 and 2009, and performs a detailed analysis on: (1 the chemical groups of these NPs; (2 the association of particular chemical groups to specific marine invertebrate taxa; and (3 the yielding of molecules from the same chemical group from organisms occurring in a particular geographic region. Our survey revealed an increasing number of new terpenoids being discovered between 2000 and 2009, contrasting with the decreasing trend in the discovery of new alkaloids and aliphatic molecules. Overall, no particular association was identified between marine invertebrate taxa and chemical groups of new NPs. Nonetheless, it is worth noting that most NPs recorded from cnidarians and mollusks were terpenoids, while most NPs identified in echinoderms were aliphatic compounds or carbohydrates. The geographical trends observed in our study do not support the idea of particular chemical groups of new NPs being associated with marine invertebrates from any specific geographical region, as NPs from different chemical groups were commonly distributed worldwide.

  3. Processing and stabilization of Aloe Vera leaf gel by adding chemical and natural preservatives

    Directory of Open Access Journals (Sweden)

    N. Nazemi

    2017-11-01

    Full Text Available Background and objectives: Aloe vera has been used as a medicinal herb for thousands of years. Aloe vera leaves can be separated into latex and gel which have biological effects. Aloe gel is a potent source of polysaccharides. When the gel is exposed to air, it quickly decomposes and decays and loses most of its biological activity. There are various processing techniques for sterilizing and stabilizing the gel. The aim of this study was to improve stabilization of the gel by adding some chemical and natural preservatives. Methods: The gel was obtained from Aloe vera leaves and after some processing chemical and natural preservatives were added. Chemicals included citric acid, ascorbic acid, vitamin E and potassium sorbate while natural preservatives were two essential oils derived from Cinnamomum zeylanicum and Eugenia caryophyllata. All these operations were performed under sterile conditions and they were evaluated at different temperatures and times. Appearance and taste changes of gel were studied organoleptic. Microbiological tests and some physical assays such as pH, refractometry and viscosity properties as well as determination of total sugars were measured. NMR and FT-IR analyses were performed for determining the quality of samples. Results: After data analyzing, the results showed that the samples formulated with chemical additives together with essential oils were more suitable and stable compared to the control samples after 90 days and the effective ingredient acemannan, remained stable. Conclusion: The stable gel can be considered for therapeutic properties and be used for edible and medicinal purposes.

  4. Molecular typing of Lactobacillus brevis isolates from Korean food using repetitive element-polymerase chain reaction.

    Science.gov (United States)

    Kaur, Jasmine; Sharma, Anshul; Lee, Sulhee; Park, Young-Seo

    2018-06-01

    Lactobacillus brevis is a part of a large family of lactic acid bacteria that are present in cheese, sauerkraut, sourdough, silage, cow manure, feces, and the intestinal tract of humans and rats. It finds its use in food fermentation, and so is considered a "generally regarded as safe" organism. L. brevis strains are extensively used as probiotics and hence, there is a need for identifying and characterizing these strains. For identification and discrimination of the bacterial species at the subspecific level, repetitive element-polymerase chain reaction method is a reliable genomic fingerprinting tool. The objective of the present study was to characterize 13 strains of L. brevis isolated from various fermented foods using repetitive element-polymerase chain reaction. Repetitive element-polymerase chain reaction was performed using three primer sets, REP, Enterobacterial Repetitive Intergenic Consensus (ERIC), and (GTG) 5 , which produced different fingerprinting patterns that enable us to distinguish between the closely related strains. Fingerprinting patterns generated band range in between 150 and 5000 bp with REP, 200-7500 bp with ERIC, and 250-2000 bp with (GTG) 5 primers, respectively. The Jaccard's dissimilarity matrices were used to obtain dendrograms by the unweighted neighbor-joining method using genetic dissimilarities based on repetitive element-polymerase chain reaction fingerprinting data. Repetitive element-polymerase chain reaction proved to be a rapid and easy method that can produce reliable results in L. brevis species.

  5. Natural and active chemical remediation of toxic metals and radionuclides in the aquatic environment

    International Nuclear Information System (INIS)

    McPherson, G.; Pintauro, P.; O'Connor, S.; Zhang, J.; Gonzales, R.; Flowers, G.

    1993-01-01

    The focus of this research is the non-biological, chemical remediation of toxic heavy metals and radionuclides in aquatic environments. This Tulane/Xavier group includes researchers from Chemistry, Chemical Engineering, and Geology. Active methods using novel zeolites and ion exchange membranes are currently being evaluated for use in removing heavy metals from natural waters. In addition, field and laboratory studies of metal ion exchange reactions and competitive, heavy metal adsorption on clay substrates are underway to determine sediment metal sequestering capacity. A summary of progress to date and future work is presented

  6. Chemical analyses of wasp-associated streptomyces bacteria reveal a prolific potential for natural products discovery

    DEFF Research Database (Denmark)

    Poulsen, Michael; Oh, Dong-Chan; Clardy, Jon

    2011-01-01

    and solitary Hymenoptera. Here we test this possibility by examining two species of solitary mud dauber wasps, Sceliphron caementarium and Chalybion californicum. We performed enrichment isolations from 33 wasps and obtained more than 200 isolates of Streptomyces Actinobacteria. Chemical analyses of 15...... and antibacterial activity. The prevalence and anti-microbial properties of Actinobacteria associated with these two solitary wasp species suggest the potential role of these Streptomyces as antibiotic-producing symbionts, potentially helping defend their wasp hosts from pathogenic microbes. Finding...... phylogenetically diverse and chemically prolific Actinobacteria from solitary wasps suggests that insect-associated Actinobacteria can provide a valuable source of novel natural products of pharmaceutical interest....

  7. Comparative proteomic profiling of soleus, extensor digitorum longus, flexor digitorum brevis and interosseus muscles from the mdx mouse model of Duchenne muscular dystrophy.

    Science.gov (United States)

    Carberry, Steven; Brinkmeier, Heinrich; Zhang, Yaxin; Winkler, Claudia K; Ohlendieck, Kay

    2013-09-01

    Duchenne muscular dystrophy is due to genetic abnormalities in the dystrophin gene and represents one of the most frequent genetic childhood diseases. In the X-linked muscular dystrophy (mdx) mouse model of dystrophinopathy, different subtypes of skeletal muscles are affected to a varying degree albeit the same single base substitution within exon 23 of the dystrophin gene. Thus, to determine potential muscle subtype-specific differences in secondary alterations due to a deficiency in dystrophin, in this study, we carried out a comparative histological and proteomic survey of mdx muscles. We intentionally included the skeletal muscles that are often used for studying the pathomechanism of muscular dystrophy. Histological examinations revealed a significantly higher degree of central nucleation in the soleus and extensor digitorum longus muscles compared with the flexor digitorum brevis and interosseus muscles. Muscular hypertrophy of 20-25% was likewise only observed in the soleus and extensor digitorum longus muscles from mdx mice, but not in the flexor digitorum brevis and interosseus muscles. For proteomic analysis, muscle protein extracts were separated by fluorescence two-dimensional (2D) gel electrophoresis. Proteins with a significant change in their expression were identified by mass spectrometry. Proteomic profiling established an altered abundance of 24, 17, 19 and 5 protein species in the dystrophin-deficient soleus, extensor digitorum longus, flexor digitorum brevis and interosseus muscle, respectively. The key proteomic findings were verified by immunoblot analysis. The identified proteins are involved in the contraction-relaxation cycle, metabolite transport, muscle metabolism and the cellular stress response. Thus, histological and proteomic profiling of muscle subtypes from mdx mice indicated that distinct skeletal muscles are differentially affected by the loss of the membrane cytoskeletal protein, dystrophin. Varying degrees of perturbed protein

  8. Degradation of non-vulcanized natural rubber - renewable resource for fine chemicals used in polymer synthesis

    Directory of Open Access Journals (Sweden)

    Alexander Fainleib

    2013-01-01

    Full Text Available In the current scenario, there is growing interest in the products of degradation of rubber (natural and synthetic for specific applications in different industry sectors, whose benefits in replacing conventionally used products are mainly related to sustainability. Since the degradation products of rubber can be used in different areas, several research groups may have the interest aroused by these products, but are not familiar with the aspects related to the chemical behavior of rubber. This review aims to bring together the key information in the published literature on the degradation of natural rubber, emphasizing metatheses reactions, oxidative damage and splitting of the double bond, in order to serve as a reference source for researchers from different fields interested in obtaining such kind of products. The structures and properties as well as additional chemical transformations resulting in oligomers of isoprene, functionalised oligomers and polymers based on both are also described.

  9. How prevalent is chemical hormesis in the natural and experimental worlds?

    Energy Technology Data Exchange (ETDEWEB)

    Mushak, Paul, E-mail: pandbmushak@cs.com

    2013-01-15

    Hormesis is described as a biological phenomenon showing bidirectional (biphasic) responses to chemical or other stressors: stimulation at low doses and inhibition at high doses or vice-versa. The label applies to either radiation or chemical hormesis. This review addresses certain critical but persisting quantitative questions about chemical hormesis. For example, what is its actual generalizability in nature? Is hormesis generalizable enough to figure in risk analysis and regulatory efforts within human or ecological toxicant exposures? No evidence exists to show that chemical hormesis is a universally distributed biological phenomenon within some law, rule or principle (100% frequency) nor is there a reliable and consistent body of evidence that leads to identifying some significant and reproducible value for frequency of occurrence below the universality standard, i.e., < 100% frequency. Lack of reliable and/or consistent evidence arises from diverse limits to study methods, i.e., methods were post-hoc evaluations of published data gathered for other purposes and using ad-hoc characterization approaches, rather than doing new studies. The literature selected for generalizability analyses has not been systematically pre-evaluated as a scientifically reliable representation of hormesis frequency in nature. Furthermore, database evaluations have used certain criteria not validated for this specific purpose, so that metric and what was measured are objects of scrutiny and ambiguity. Finally, simultaneous estimates of frequency of non-hormetic dose–response relationships, required for reliable determinations of hormesis frequency, were not done in these analyses. Chemical hormesis frequency estimates vary with conditions for characterization. For all these reasons, chemical hormesis still has limited use in health policy and regulatory thinking. - Highlights: ► Hormesis is not a universally distributed biological phenomenon (100% frequency). ► There is also no

  10. How prevalent is chemical hormesis in the natural and experimental worlds?

    International Nuclear Information System (INIS)

    Mushak, Paul

    2013-01-01

    Hormesis is described as a biological phenomenon showing bidirectional (biphasic) responses to chemical or other stressors: stimulation at low doses and inhibition at high doses or vice-versa. The label applies to either radiation or chemical hormesis. This review addresses certain critical but persisting quantitative questions about chemical hormesis. For example, what is its actual generalizability in nature? Is hormesis generalizable enough to figure in risk analysis and regulatory efforts within human or ecological toxicant exposures? No evidence exists to show that chemical hormesis is a universally distributed biological phenomenon within some law, rule or principle (100% frequency) nor is there a reliable and consistent body of evidence that leads to identifying some significant and reproducible value for frequency of occurrence below the universality standard, i.e., < 100% frequency. Lack of reliable and/or consistent evidence arises from diverse limits to study methods, i.e., methods were post-hoc evaluations of published data gathered for other purposes and using ad-hoc characterization approaches, rather than doing new studies. The literature selected for generalizability analyses has not been systematically pre-evaluated as a scientifically reliable representation of hormesis frequency in nature. Furthermore, database evaluations have used certain criteria not validated for this specific purpose, so that metric and what was measured are objects of scrutiny and ambiguity. Finally, simultaneous estimates of frequency of non-hormetic dose–response relationships, required for reliable determinations of hormesis frequency, were not done in these analyses. Chemical hormesis frequency estimates vary with conditions for characterization. For all these reasons, chemical hormesis still has limited use in health policy and regulatory thinking. - Highlights: ► Hormesis is not a universally distributed biological phenomenon (100% frequency). ► There is also no

  11. Economic potential of natural gas-fired cogeneration--analysis of Brazil's chemical industry

    International Nuclear Information System (INIS)

    Szklo, A.S.; Soares, J.B.; Tolmasquim, M.T.

    2004-01-01

    This paper attempts to estimate the technical and economic potential for natural gas-fired cogeneration (NGCHP) in Brazil's chemical industry as well as also analyses the impacts of specific incentive policies on the economic feasibility of this potential. Currently, the NGCHP installed capacity at Brazil's chemical industry is still quite a low figure, although the chemical plants are under heavy pressures to: (1) cut costs; and (2) show a rising awareness of the importance of power service quality, underscored even more heavily by Brazil's recent power crisis. According this study, a natural gas-fired remaining technical potential of 1.4 GW is noted in the Brazilian chemical industry. Financing policies showed to be the stand-alone policy that would be most successful for ensuring the economic feasibility of this technical potential. Nevertheless, this policy proved to be affected by the economic scenario under consideration, which includes world oil prices, electricity tariff and foreign exchange ratio possible paths. Consequently, the key issue is related to the ability to assess which economic scenario is rated as more probable by possible future investors in NGCHP, and then selecting the most appropriate incentive policy

  12. Target identification of natural and traditional medicines with quantitative chemical proteomics approaches.

    Science.gov (United States)

    Wang, Jigang; Gao, Liqian; Lee, Yew Mun; Kalesh, Karunakaran A; Ong, Yong Siang; Lim, Jaehong; Jee, Joo-Eun; Sun, Hongyan; Lee, Su Seong; Hua, Zi-Chun; Lin, Qingsong

    2016-06-01

    Natural and traditional medicines, being a great source of drugs and drug leads, have regained wide interests due to the limited success of high-throughput screening of compound libraries in the past few decades and the recent technology advancement. Many drugs/bioactive compounds exert their functions through interaction with their protein targets, with more and more drugs showing their ability to target multiple proteins, thus target identification has an important role in drug discovery and biomedical research fields. Identifying drug targets not only furthers the understanding of the mechanism of action (MOA) of a drug but also reveals its potential therapeutic applications and adverse side effects. Chemical proteomics makes use of affinity chromatography approaches coupled with mass spectrometry to systematically identify small molecule-protein interactions. Although traditional affinity-based chemical proteomics approaches have made great progress in the identification of cellular targets and elucidation of MOAs of many bioactive molecules, nonspecific binding remains a major issue which may reduce the accuracy of target identification and may hamper the drug development process. Recently, quantitative proteomics approaches, namely, metabolic labeling, chemical labeling, or label-free approaches, have been implemented in target identification to overcome such limitations. In this review, we will summarize and discuss the recent advances in the application of various quantitative chemical proteomics approaches for the identification of targets of natural and traditional medicines. Copyright © 2016. Published by Elsevier Inc.

  13. Molecular cloning of a putative divalent-cation transporter gene as a new genetic marker for the identification of Lactobacillus brevis strains capable of growing in beer.

    Science.gov (United States)

    Hayashi, N; Ito, M; Horiike, S; Taguchi, H

    2001-05-01

    Random amplified polymorphic DNA (RAPD) PCR analysis of Lactobacillus brevis isolates from breweries revealed that one of the random primers could distinguish beer-spoilage strains of L. brevis from nonspoilage strains. The 1.1-kb DNA fragment amplified from all beer-spoilers included one open reading frame, termed hitA (hop-inducible cation transporter), which encodes an integral membrane protein with 11 putative trans-membrane domains and a binding protein-dependent transport signature of a non-ATP binding membrane transporter common to several prokaryotic and eukaryotic transporters. The hitA polypeptide is homologous to the natural resistance-associated macrophage protein (Nramp) family characterized as divalent-cation transport proteins in many prokaryotic and eukaryotic organisms. Northern blot analysis indicated that the hitA transcripts are expressed in cells cultivated in MRS broth supplemented with hop bitter compounds, which act as mobile-carrier ionophores, dissipating the trans-membrane pH gradient in bacteria sensitive to the hop bitter compounds by exchanging H+ for cellular divalent cations such as Mn2+. This suggests that the hitA gene products may play an important role in making the bacteria resistant to hop bitter compounds in beer by transporting metal ions such as Mn2+ into cells that no longer maintain the proton gradient.

  14. Effect of Chemical Treatment on Physical, Mechanical and Thermal Properties of Ladies Finger Natural Fiber

    Directory of Open Access Journals (Sweden)

    S. I. Hossain

    2013-01-01

    Full Text Available In present research, natural fiber obtained from ladies finger plant was chemically treated separately using alkali (2% NaOH, chromium sulfate (4% , and chromium sulfate and sodium bicarbonate (4% . Both raw and chemically treated fibers were subsequently characterized using mechanical (tensile, structural (Fourier transform infrared spectroscopy and scanning electron microscopy, and thermal (thermogravimetric analysis. Fourier analysis showed the presence of (−OH group in the ladies plant fiber. Scanning electron micrographs revealed rougher surface in case of alkali treated fiber, while thin coating layer was formed on the fiber surface during other two treatments. Tensile test on ladies finger single fiber was carried out by varying span length. The tensile strength and Young's modulus values were found to be increased after chemical treatment. For both raw and chemically treated fibers, Young's modulus increased and tensile strength decreased with increase in span length. Thermogravimetric analysis indicated the same level of thermal stability for both raw and treated ladies finger fibers.

  15. Internal Domains of Natural Porous Media Revealed: Critical Locations for Transport, Storage, and Chemical Reaction

    Energy Technology Data Exchange (ETDEWEB)

    Zachara, John M.; Brantley, Susan L.; Chorover, Jon D.; Ewing, Robert P.; Kerisit, Sebastien N.; Liu, Chongxuan; Perfect, E.; Rother, Gernot; Stack, Andrew G.

    2016-03-16

    Internal pore domains exist within rocks, lithic fragments, subsurface sediments and soil aggregates. These domains, which we term internal domains in porous media (IDPM), contain a significant fraction of their porosity as nanopores, dominate the reactive surface area of diverse porous media types, and are important locations for chemical reactivity and hydrocarbon storage. Traditionally difficult to interrogate, advances in instrumentation and imaging methods are providing new insights on the physical structures and chemical attributes of IDPM. In this review we: discuss analytical methods to characterize IDPM, evaluate what has been learned about their size distributions, connectivity, and extended structures; determine whether they exhibit unique chemical reactivity; and assess potential for their inclusion in reactive transport models. Three key findings are noteworthy. 1) A combination of methods now allows complete characterization of the porosity spectrum of natural materials and its connectivity; while imaging microscopies are providing three dimensional representations of the interconnected pore network. 2) Chemical reactivity in pores <10 nm is expected to be different from micro and macropores, yet research performed to date is inconclusive on the nature, direction, and magnitude of effect. 3) Existing continuum reactive transport models treat IDPM as a sub-grid feature with average, empirical, scale-dependent parameters; and are not formulated to include detailed information on pore networks. Overall we find that IDPM are key features controlling hydrocarbon release from shales in hydrofracking systems, organic matter stabilization and recalcitrance in soil, weathering and soil formation, and long term inorganic and organic contaminant behavior in the vadose zone and groundwater. We conclude with an assessment of impactful research opportunities to advance understanding of IDPM, and to incorporate their important effects in reactive transport models

  16. Analysing and Navigating Natural Products Space for Generating Small, Diverse, But Representative Chemical Libraries.

    Science.gov (United States)

    O'Hagan, Steve; Kell, Douglas B

    2018-01-01

    Armed with the digital availability of two natural products libraries, amounting to some 195 885 molecular entities, we ask the question of how we can best sample from them to maximize their "representativeness" in smaller and more usable libraries of 96, 384, 1152, and 1920 molecules. The term "representativeness" is intended to include diversity, but for numerical reasons (and the likelihood of being able to perform a QSAR) it is necessary to focus on areas of chemical space that are more highly populated. Encoding chemical structures as fingerprints using the RDKit "patterned" algorithm, we first assess the granularity of the natural products space using a simple clustering algorithm, showing that there are major regions of "denseness" but also a great many very sparsely populated areas. We then apply a "hybrid" hierarchical K-means clustering algorithm to the data to produce more statistically robust clusters from which representative and appropriate numbers of samples may be chosen. There is necessarily again a trade-off between cluster size and cluster number, but within these constraints, libraries containing 384 or 1152 molecules can be found that come from clusters that represent some 18 and 30% of the whole chemical space, with cluster sizes of, respectively, 50 and 27 or above, just about sufficient to perform a QSAR. By using the online availability of molecules via the Molport system (www.molport.com), we are also able to construct (and, for the first time, provide the contents of) a small virtual library of available molecules that provided effective coverage of the chemical space described. Consistent with this, the average molecular similarities of the contents of the libraries developed is considerably smaller than is that of the original libraries. The suggested libraries may have use in molecular or phenotypic screening, including for determining possible transporter substrates. © 2017 The Authors. Biotechnology Journal Published by Wiley

  17. Optimization of γ-amino butyric acid production in a newly isolated Lactobacillus brevis.

    Science.gov (United States)

    Binh, Tran Thi Thanh; Ju, Wan-Taek; Jung, Woo-Jin; Park, Ro-Dong

    2014-01-01

    An isolate from kimchi, identified as Lactobacillus brevis, accumulated γ-aminobutyric acid (GABA), a major inhibitory neurotransmitter, in the culture medium. Optimal culture conditions for growth of L. brevis and production of GABA were 6 % (w/v) l-glutamic acid, 4 % (w/v) maltose, 2 % (w/v) yeast extract, 1 % (w/v) NaCl, 1 % (w/v) CaCl2, 2 g Tween 80/l, and 0.02 mM pyridoxal 5′-phosphate at initial pH 5.25 and 37 °C. GABA reached 44.4 g/l after 72 h cultivation with a conversion rate 99.7 %, based on the amount (6 %) of l-glutamic acid added. GABA was purified using ion exchange column chromatography with 70 % recovery and 97 % purity.

  18. Lactic acid production from wheat straw hemicellulose hydrolysate by Lactobacillus pentosus and Lactobacillus brevis

    DEFF Research Database (Denmark)

    Garde, Arvid; Jonsson, Gunnar Eigil; Schmidt, A. S.

    2002-01-01

    Lactic acid production by Lactobacillus brevis and Lactobacillus pentosus on a hemicellulose hydrolysate (HH) of wet-oxidized wheat straw was evaluated. The potential of 11-12 g/l fermentable sugars was released from the HH through either enzymatic or acidic pretreatment. Fermentation of added......% of the theoretical maximum yield after enzymatic, or acid treatment of HH, respectively. Individually, neither of the two strains were able to fully utilize the relatively broad spectra of sugars released by the acid and enzyme treatments; however, lactic acid production increased to 95% of the theoretical maximum...... yield by co-inoculation of both strains. Xylulose was the main sugar released after enzymatic treatment of HH with Celluclast(R). Lb. brevis was able to degrade xylobiose, but was unable to assimilate xylulose, whereas Lb. pentosus was able to assimilate xylulose but unable to degrade xylobiose. (C...

  19. Characterization of Lactobacillus brevis L62 strain, highly tolerant to copper ions.

    Science.gov (United States)

    Mrvčić, Jasna; Butorac, Ana; Solić, Ema; Stanzer, Damir; Bačun-Družina, Višnja; Cindrić, Mario; Stehlik-Tomas, Vesna

    2013-01-01

    Lactic acid bacteria (LAB) as starter culture in food industry must be suitable for large-scale industrial production and possess the ability to survive in unfavorable processes and storage conditions. Approaches taken to address these problems include the selection of stress-resistant strains. In food industry, LAB are often exposed to metal ions induced stress. The interactions between LAB and metal ions are very poorly investigated. Because of that, the influence of non-toxic, toxic and antioxidant metal ions (Zn, Cu, and Mn) on growth, acid production, metal ions binding capacity of wild and adapted species of Leuconostoc mesenteroides L3, Lactobacillus brevis L62 and Lactobacillus plantarum L73 were investigated. The proteomic approach was applied to clarify how the LAB cells, especially the adapted ones, protect themselves and tolerate high concentrations of toxic metal ions. Results have shown that Zn and Mn addition into MRS medium in the investigated concentrations did not have effect on the bacterial growth and acid production, while copper ions were highly toxic, especially in static conditions. Leuc. mesenteroides L3 was the most efficient in Zn binding processes among the chosen LAB species, while L. plantarum L73 accumulated the highest concentration of Mn. L. brevis L62 was the most copper resistant species. Adaptation had a positive effect on growth and acid production of all species in the presence of copper. However, the adapted species incorporated less metal ions than the wild species. The exception was adapted L. brevis L62 that accumulated high concentration of copper ions in static conditions. The obtained results showed that L. brevis L62 is highly tolerant to copper ions, which allows its use as starter culture in fermentative processes in media with high concentration of copper ions.

  20. Heterogeneity between and within Strains of Lactobacillus brevis Exposed to Beer Compounds

    OpenAIRE

    Zhao, Yu; Knøchel, Susanne; Siegumfeldt, Henrik

    2017-01-01

    This study attempted to investigate the physiological response of six Lactobacillus brevis strains to hop stress, with and without the addition of Mn2+ or ethanol. Based on the use of different fluorescent probes, cell viability and intracellular pH (pHi) were assessed by fluorescence microscopy combined with flow cytometry, at the single cell level. The combined approach was faster than the traditional colony based method, but also provided additional information about population heterogenei...

  1. Technical approaches of a natural dye extracted from Phytolacca americana L.-berries with chemical mordants.

    Science.gov (United States)

    Park, Su-Youn; Jung, Suk-Yul

    2014-01-01

    Phytolacca americana L. is a large semi-succulent herbaceous plant which reaches three meters in height. It is native to eastern North America, the Midwest, and the Gulf Coast, with more scattered populations in the far West. It is imported into Korea and has been frequently used as a traditional natural drug for diseases such as systemic edema and nephritis. Its berries, that is, fruits are shiny dark purple held in racemous clusters on pink pedicels with a pink peduncle. They are round with a flat indented top and bottom. Immature berries are green, maturing into white and then blackish purple. It is not well known how the berries are used for a natural staining yet. In this study, using Phytolacca americana L.-berries, a natural staining was analyzed. Moreover, due to the broad use of chemical mordants, five different mordants including copper acetate, aluminum potassium sulfate, sodium tartrate plus citric acid, Iron II sulfate and potassium dichromate were combined. Extracted dye from the berries stained silk fabrics with ivory. The original purple color from the berries disappeared and transformed into ivory. Although the silk fabrics were differentially stained by the berries that were combined with mordants of aluminum potassium sulfate, sodium tartrate plus citric acid and potassium dichromate, only differences in lightness and darkness were observed. Interestingly, the combination of the dye from the berries with a mordant of copper acetate and Iron II sulfate induced the staining of the silk fabrics into khaki and dark khaki, respectively. This study is the first systemic report on staining silk fabrics with Phytolacca americana L.-berries and chemical mordants and suggests application of natural products to the fiber industry.

  2. Characterization of an epoxide hydrolase from the Florida red tide dinoflagellate, Karenia brevis.

    Science.gov (United States)

    Sun, Pengfei; Leeson, Cristian; Zhi, Xiaoduo; Leng, Fenfei; Pierce, Richard H; Henry, Michael S; Rein, Kathleen S

    2016-02-01

    Epoxide hydrolases (EH, EC 3.3.2.3) have been proposed to be key enzymes in the biosynthesis of polyether (PE) ladder compounds such as the brevetoxins which are produced by the dinoflagellate Karenia brevis. These enzymes have the potential to catalyze kinetically disfavored endo-tet cyclization reactions. Data mining of K. brevis transcriptome libraries revealed two classes of epoxide hydrolases: microsomal and leukotriene A4 (LTA4) hydrolases. A microsomal EH was cloned and expressed for characterization. The enzyme is a monomeric protein with molecular weight 44kDa. Kinetic parameters were evaluated using a variety of epoxide substrates to assess substrate selectivity and enantioselectivity, as well as its potential to catalyze the critical endo-tet cyclization of epoxy alcohols. Monitoring of EH activity in high and low toxin producing cultures of K. brevis over a three week period showed consistently higher activity in the high toxin producing culture implicating the involvement of one or more EH in brevetoxin biosynthesis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Identification of ecotype-specific marker genes for categorization of beer-spoiling Lactobacillus brevis.

    Science.gov (United States)

    Behr, Jürgen; Geissler, Andreas J; Preissler, Patrick; Ehrenreich, Armin; Angelov, Angel; Vogel, Rudi F

    2015-10-01

    The tolerance to hop compounds, which is mainly associated with inhibition of bacterial growth in beer, is a multi-factorial trait. Any approaches to predict the physiological differences between beer-spoiling and non-spoiling strains on the basis of a single marker gene are limited. We identified ecotype-specific genes related to the ability to grow in Pilsner beer via comparative genome sequencing. The genome sequences of four different strains of Lactobacillus brevis were compared, including newly established genomes of two highly hop tolerant beer isolates, one strain isolated from faeces and one published genome of a silage isolate. Gene fragments exclusively occurring in beer-spoiling strains as well as sequences only occurring in non-spoiling strains were identified. Comparative genomic arrays were established and hybridized with a set of L. brevis strains, which are characterized by their ability to spoil beer. As result, a set of 33 and 4 oligonucleotide probes could be established specifically detecting beer-spoilers and non-spoilers, respectively. The detection of more than one of these marker sequences according to a genetic barcode enables scoring of L. brevis for their beer-spoiling potential and can thus assist in risk evaluation in brewing industry. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Isolation and characterization of a biosurfactant producing strain, Brevibacilis brevis HOB1.

    Science.gov (United States)

    Haddad, Namir I A; Wang, Ji; Mu, Bozhong

    2008-12-01

    Biosurfactant-producing bacteria were isolated from the production water of an oil field. Isolates were screened for biosurfactant production using surface tension test. The highest reduction of surface tension was achieved with a bacterial strain which was identified by 16S rRNA gene sequencing as Brevibacilis brevis HOB1. It has been investigated using different carbon and nitrogen sources. It showed that the strain was able to grow and reduce the surface tension of the broth to 29 mN/m on commercial sugar and maltose, and to 32 mN/m on glucose after 72 h of growth. The maximum amount of biosurfactant was obtained when nitrate ions were supplied as nitrogen source. Biosurfactant produced by Brevibacilis brevis HOB1 was confirmed as a lipopeptide class of biosurfactant using TLC test and mass spectra. Lipopeptide isoforms were isolated from cell-free supernatants by acid-precipitation followed by one step of chromatographic separation on solid-phase ODS C18 column. The separation was confirmed by HPLC and ESI Q-TOF MS spectroscopy. Comparing the mass data obtained and the mass numbers reported for the lipopeptide complexes from other strains, it can be concluded that the major lipopeptide product of Brevibacilis brevis HOB1 is the surfactin isoform. This lipopeptide showed strong antibacterial and antifungal activity. It is a candidate for the biocontrol of pathogens in agriculture and other industries.

  5. Evaluation of Brevibacillus brevis as a potential plant growth promoting rhizobacteria for cotton (Gossypium hirsutum) crop.

    Science.gov (United States)

    Nehra, Vibha; Saharan, Baljeet Singh; Choudhary, Madhu

    2016-01-01

    The present investigation was undertaken to isolate, screen and evaluate a selected promising PGPR Brevibacillus brevis on cotton crop. Out of 156 bacterial isolates one of the most promising isolate was analyzed for the various PGP traits. A seed germination analysis was conducted with cotton seeds to evaluate the potential of the isolate to promote plant growth. The bacterial isolate was checked for its growth and survival at high temperatures. The isolate was also analyzed for the PGP traits exhibited after the heat treatment. To identify the isolate morphological, biochemical and molecular characterization was performed. The isolate was found positive for many of the PGP attributes like IAA, ARA, anti-fungal activity and ammonia production. Effect of seed bacterization on various plant growth parameters was used as an indicator. The isolate showed significant growth and exhibited various PGP traits at high temperature making it suitable as an inoculant for cotton crop. Isolate was identified as Brevibacillus brevis [SVC(II)14] based on phenotypic as well as genotypic attributes and after conducting this research we propose that the B. brevis which is reported for the first time for its PGP potential in cotton, exerts its beneficial effects on cotton crop through combined modes of actions.

  6. Biological and Chemical Aspects of Natural Biflavonoids from Plants: A Brief Review.

    Science.gov (United States)

    Gontijo, Vanessa Silva; Dos Santos, Marcelo Henrique; Viegas, Claudio

    2017-01-01

    Biflavonoids belong to a subclass of the plant flavonoids family and are limited to several species in the plant kingdom. In the literature, biflavonoids are extensively reported for their pharmacological properties including anti-inflammatory, antioxidant, inhibitory activity against phospholipase A2 (PLA2) and antiprotozoal activity. These activities have been discovered from the small number of biflavonoid structures that have been investigated, although the natural biflavonoids library is likely to be large. In addition, many medicinal properties and traditional use of plants are attributed to the presence of bioflavonoids among their secondary metabolites. Structurally, biflavonoids are polyphenol compounds comprising of two identical or non-identical flavonflavonoid units joined in a symmetrical or unsymmetrical manner through an alkyl or an alkoxy-based linker of varying length. Due to their chemical and biological importance, several bioprospective phytochemical studies and chemical approaches using coupling and molecular rearrangement strategies have been developed to identify and synthesize new bioactive biflavonoids. In this brief review, we present some basic structural aspects for classification and nomenclature of bioflavonoids and a compilation of the literature data published in the last 7 years, concerning the discovery of new natural biflavonoids of plant origin and their pharmacological and biological properties. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  7. Influence of chemical composition of precipitation on migration of radioactive caesium in natural soils

    International Nuclear Information System (INIS)

    Thørring, H.; Skuterud, L.; Steinnes, E.

    2014-01-01

    The aim of the present work was to study the impact of the chemical composition of precipitation on radiocaesium mobility in natural soil. This was done through column studies. Three types of precipitation regimes were studied, representing a natural range found in Norway: Acidic precipitation (southernmost part of the country); precipitation rich in marine cations (highly oceanic coastal areas); and low concentrations of sea salts (slightly continental inland areas). After 50 weeks and a total precipitation supply of ∼10 000 L m −2 per column, results indicate that acidic precipitation increased the mobility of 134 Cs added during the experiment. However, depth distribution of already present Chernobyl fallout 137 Cs was not significantly affected by the chemical composition of precipitation. - Highlights: • Mobility of freshly added Cs-134 was higher in soil receiving acidic precipitation. • Depth penetration of Cs-134 was higher in soil profiles with a thicker humus layer. • Depth distribution of Chernobyl Cs-137 was not affected by precipitation type

  8. Chemical analyses of wasp-associated streptomyces bacteria reveal a prolific potential for natural products discovery.

    Directory of Open Access Journals (Sweden)

    Michael Poulsen

    2011-02-01

    Full Text Available Identifying new sources for small molecule discovery is necessary to help mitigate the continuous emergence of antibiotic-resistance in pathogenic microbes. Recent studies indicate that one potentially rich source of novel natural products is Actinobacterial symbionts associated with social and solitary Hymenoptera. Here we test this possibility by examining two species of solitary mud dauber wasps, Sceliphron caementarium and Chalybion californicum. We performed enrichment isolations from 33 wasps and obtained more than 200 isolates of Streptomyces Actinobacteria. Chemical analyses of 15 of these isolates identified 11 distinct and structurally diverse secondary metabolites, including a novel polyunsaturated and polyoxygenated macrocyclic lactam, which we name sceliphrolactam. By pairing the 15 Streptomyces strains against a collection of fungi and bacteria, we document their antifungal and antibacterial activity. The prevalence and anti-microbial properties of Actinobacteria associated with these two solitary wasp species suggest the potential role of these Streptomyces as antibiotic-producing symbionts, potentially helping defend their wasp hosts from pathogenic microbes. Finding phylogenetically diverse and chemically prolific Actinobacteria from solitary wasps suggests that insect-associated Actinobacteria can provide a valuable source of novel natural products of pharmaceutical interest.

  9. The effect of natural weathering on the chemical and isotopic composition of biotites

    International Nuclear Information System (INIS)

    Clauer, N.; Bonnot-Courtois, C.

    1982-01-01

    The effect of progressive natural weathering on the isotopic (Rb-Sr, K-Ar, deltaD, delta 18 O) and chemical (REE, H 2 O + ) compositions of biotite has been studied on a suite of migmatitic biotites from the Chad Republic. During the early stages of weathering the Rb-Sr system is strongly affected, the hydrogen and oxygen isotope compositions change markedly, the minerals are depleted in light REE, the water content increases by a factor of two, and the K-Ar system is relatively little disturbed. During intensive weathering the K-Ar system is more strongly disturbed than the Rb-Sr system. Most of the isotopic and chemical modifications take place under nonequilibrium conditions and occur before newly formed kaolinite and/or smectite can be detected. These observations suggest that (a) 'protominerals' may form within the biotite structure during the initial period of weathering, and (b) only when chemical equilibrium is approached in the weathering profile are new minerals able to form. (author)

  10. Chemical communication between synthetic and natural cells: a possible experimental design.

    Directory of Open Access Journals (Sweden)

    Livia Leoni

    2013-09-01

    Full Text Available The bottom-up construction of synthetic cells is one of the most intriguing and interesting research arenas in synthetic biology. Synthetic cells are built by encapsulating biomolecules inside lipid vesicles (liposomes, allowing the synthesis of one or more functional proteins. Thanks to the in situ synthesized proteins, synthetic cells become able to perform several biomolecular functions, which can be exploited for a large variety of applications. This paves the way to several advanced uses of synthetic cells in basic science and biotechnology, thanks to their versatility, modularity, biocompatibility, and programmability. In the previous WIVACE (2012 we presented the state-of-the-art of semi-synthetic minimal cell (SSMC technology and introduced, for the first time, the idea of chemical communication between synthetic cells and natural cells. The development of a proper synthetic communication protocol should be seen as a tool for the nascent field of bio/chemical-based Information and Communication Technologies (bio-chem-ICTs and ultimately aimed at building soft-wet-micro-robots. In this contribution (WIVACE, 2013 we present a blueprint for realizing this project, and show some preliminary experimental results. We firstly discuss how our research goal (based on the natural capabilities of biological systems to manipulate chemical signals finds a proper place in the current scientific and technological contexts. Then, we shortly comment on the experimental approaches from the viewpoints of (i synthetic cell construction, and (ii bioengineering of microorganisms, providing up-to-date results from our laboratory. Finally, we shortly discuss how autopoiesis can be used as a theoretical framework for defining synthetic minimal life, minimal cognition, and as bridge between synthetic biology and artificial intelligence.

  11. Occurrence of pesticide non extractable residues in physical and chemical fractions from two natural soils.

    Science.gov (United States)

    Andreou, K.; Jones, K.; Semple, K.

    2009-04-01

    Distribution of pesticide non extractable residues resulted from the incubation of two natural soils with each of the isoproturon, diazinon and cypermethrin pesticide was assessed in this study. Pesticide non extractable residues distribution in soil physical and chemical fractions is known to ultimately affect their fate. This study aimed to address the fate and behaviour of the non extractable residues in the context of their association with soil physical and chemical fractions with varying properties and characteristics. Non extractable residues were formed from incubation of each pesticide in the two natural soils over a period of 24 months. Soils containing the non extractable residues were fractionated into three solid phase fractions using a physical fractionation procedure as follows: Sediment (SED, >20 μm), (II) Microaggregate (MA, 20-2 μm) and (III) Colloid phase (COL, 2-0.05 μm). Each soil fraction was then fractionated into organic carbon chemical fractionations as follows: Fulvic acid (FA), Humic acid (HA) and Humin (HM). Significant amount of the pesticides was lost during the incubation period. Enrichment factors for the organic carbon and the 14C-pesticide residues were higher in the MA and COL fraction rather than the SED fraction. Greater association and enrichment of the fulvic acid fraction of the organic carbon in the soil was observed. Non extractable residues at the FA fraction showed to diminish while in the HA fraction were increased with decreasing the fraction size. An appreciable amount of non extractable residues were located in the HM fraction but this was less than the amount recovered in the humic substances. Long term fate of pesticide non extractable residues in the soil structural components is important in order to assess any risk associated with them.

  12. Chemical Editing of Macrocyclic Natural Products and Kinetic Profiling Reveal Slow, Tight-Binding Histone Deacetylase Inhibitors with Picomolar Affinities

    DEFF Research Database (Denmark)

    Kitir, Betül; Maolanon, Alex R.; Ohm, Ragnhild G.

    2017-01-01

    medicines. Therefore, detailed mechanistic information and precise characterization of the chemical probes used to investigate the effects of HDAC enzymes are vital. We interrogated Nature's arsenal of macrocyclic nonribosomal peptide HDAC inhibitors by chemical synthesis and evaluation of more than 30...... natural products and analogues. This furnished surprising trends in binding affinities for the various macrocycles, which were then exploited for the design of highly potent class I and IIb HDAC inhibitors. Furthermore, thorough kinetic investigation revealed unexpected inhibitory mechanisms of important...

  13. Oxygen-Inducible Conversion of Lactate to Acetate in Heterofermentative Lactobacillus brevis ATCC 367.

    Science.gov (United States)

    Guo, Tingting; Zhang, Li; Xin, Yongping; Xu, ZhenShang; He, Huiying; Kong, Jian

    2017-11-01

    Lactobacillus brevis is an obligatory heterofermentative lactic acid bacterium that produces high levels of acetate, which improve the aerobic stability of silages against deterioration caused by yeasts and molds. However, the mechanism involved in acetate accumulation has yet to be elucidated. Here, experimental evidence indicated that aerobiosis resulted in the conversion of lactate to acetate after glucose exhaustion in L. brevis ATCC 367 (GenBank accession number NC_008497). To elucidate the conversion pathway, in silico analysis showed that lactate was first converted to pyruvate by the reverse catalytic reaction of lactate dehydrogenase (LDH); subsequently, pyruvate conversion to acetate might be mediated by pyruvate dehydrogenase (PDH) or pyruvate oxidase (POX). Transcriptional analysis indicated that the pdh and pox genes of L. brevis ATCC 367 were upregulated 37.92- and 18.32-fold, respectively, by oxygen and glucose exhaustion, corresponding to 5.32- and 2.35-fold increases in the respective enzyme activities. Compared with the wild-type strain, the transcription and enzymatic activity of PDH remained stable in the Δ pox mutant, while those of POX increased significantly in the Δ pdh mutant. More lactate but less acetate was produced in the Δ pdh mutant than in the wild-type and Δ pox mutant strains, and more H 2 O 2 (a product of the POX pathway) was produced in the Δ pdh mutant. We speculated that the high levels of aerobic acetate accumulation in L. brevis ATCC 367 originated mainly from the reuse of lactate to produce pyruvate, which was further converted to acetate by the predominant and secondary functions of PDH and POX, respectively. IMPORTANCE PDH and POX are two possible key enzymes involved in aerobic acetate accumulation in lactic acid bacteria (LAB). It is currently thought that POX plays the major role in aerobic growth in homofermentative LAB and some heterofermentative LAB, while the impact of PDH remains unclear. In this study, we

  14. Reassigning the Structures of Natural Products Using NMR Chemical Shifts Computed with Quantum Mechanics: A Laboratory Exercise

    Science.gov (United States)

    Palazzo, Teresa A.; Truong, Tiana T.; Wong, Shirley M. T.; Mack, Emma T.; Lodewyk, Michael W.; Harrison, Jason G.; Gamage, R. Alan; Siegel, Justin B.; Kurth, Mark J.; Tantillo, Dean J.

    2015-01-01

    An applied computational chemistry laboratory exercise is described in which students use modern quantum chemical calculations of chemical shifts to assign the structure of a recently isolated natural product. A pre/post assessment was used to measure student learning gains and verify that students demonstrated proficiency of key learning…

  15. Characterization of the binding of the Ptychodiscus brevis neurotoxin T17 to sodium channels in rat brain synaptosomes

    International Nuclear Information System (INIS)

    Poli, M.A.

    1985-01-01

    The lipid-soluble polyether neurotoxins isolated from the marine dinoflagellate Ptychodiscus brevis (formerly Gymnodinium breve) have been determined to bind to a unique receptor site associated with the voltage-sensitive sodium channel in rat brain synaptosomes. Reduction of the C 42 aldehyde function of T34 to the alcohol function of T17 using NaB 3 H 4 yielded 3 H-T17 with a specific activity of 15 Ci;/mmol. Using this specific probe, binding to sodium channels was measured at 4 0 CC, 22 0 C, and 37 0 C. Rosenthal analysis of the binding data yielded a K/sub d/ of 2.9 nM and B/sub max/ of 6.8 pmoles 3 H-T17 per mg of synaptosomal protein at 4 0 C. Both K/sub d/ and B/sub max/ were found to be temperature dependent. Depolarization of the synaptosomes by osmotic lysis resulted in the loss of 34% of the available receptor sites, with no decrease in binding affinity. Unlabeled T17, T34, and synthetic T17 (reduced T34) were equipotent in their ability to displace 3 H-T17 from its specific receptor site. Competition experiments using natural toxin probes specific for sites I-IV on the voltage-sensitive sodium channel demonstrate that 3 H-T17 does not bind to any of the previously-described neurotoxin receptor sites. A fifth site is proposed

  16. Cryptotermes brevis (Isoptera: Kalotermitidae) in the Azores: lessons after 2 yr of monitoring in the Archipelago.

    Science.gov (United States)

    Borges, Paulo A V; Guerreiro, Orlando; Ferreira, Maria T; Borges, Annabella; Ferreira, Filomena; Bicudo, Nuno; Nunes, Lina; Marcos, Rita S; Arroz, Ana M; Scheffrahn, Rudolf H; Myles, Timothy G

    2014-01-01

    The dispersal flights of West Indian drywood termite, Cryptotermes brevis (Walker) (Isoptera: Kalotermitidae) were surveyed in the major cities of Azores. The sampling device used to estimate termite density consisted of a yellow adhesive trap (size 45 by 24 cm), placed with an artificial or natural light source in a dark attic environment. In addition, data from two other projects were used to improve the knowledge about the geographical distribution of the species. The level of infestation in the two main Azorean towns differed, with high levels in the houses of Angra do Heroísmo, whereas in Ponta Delgada, there are fewer houses with high levels of infestation. The infestation in Ponta Delgada shows a pattern of spreading from the center outward to the city's periphery, whereas in Angra do Heroísmo, there was a pattern of spreading outward from several foci. The heavy infestation observed in Angra do Heroísmo and the clear increase of infestation levels observed from 2010 to 2011 is a reason for concern and calls for an urgent application of an Integrated Pest Management (IPM) control strategy. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

  17. Transformation processes influencing physico-chemical forms of radionuclides and trace elements in natural water systems

    International Nuclear Information System (INIS)

    Salbu, B.; Riise, G.; Oughton, D.H.

    1995-01-01

    In order to assess short and long term consequences of radionuclides and trace elements introduced to aquatic systems, knowledge on source terms, key factors and key processes influencing the speciation is essential. The mobility, bioavailability and subsequent transfer into food chains depend on the physico-chemical forms on radionuclides and trace metals. In addition, transformation processes and especially the interaction with natural organic matter (NOM) influences the distribution pattern. Furthermore, the prevailing climate conditions, e.g. episodic events and temperature are vital for fluxes and for the kinetics of the transformation processes. In the present work processes in catchments and processes associated with acidification, episodic events, climate conditions (temperature) and mixing zone phenomena influencing the speciation of radionuclides and trace metals are highlighted. These processes should be highly relevant for assessing far field consequences of radionuclides potentially released from disposal sites. (authors). 21 refs., 8 figs., 1 tab

  18. Nature and prevalence of non-additive toxic effects in industrially relevant mixtures of organic chemicals.

    Science.gov (United States)

    Parvez, Shahid; Venkataraman, Chandra; Mukherji, Suparna

    2009-06-01

    The concentration addition (CA) and the independent action (IA) models are widely used for predicting mixture toxicity based on its composition and individual component dose-response profiles. However, the prediction based on these models may be inaccurate due to interaction among mixture components. In this work, the nature and prevalence of non-additive effects were explored for binary, ternary and quaternary mixtures composed of hydrophobic organic compounds (HOCs). The toxicity of each individual component and mixture was determined using the Vibrio fischeri bioluminescence inhibition assay. For each combination of chemicals specified by the 2(n) factorial design, the percent deviation of the predicted toxic effect from the measured value was used to characterize mixtures as synergistic (positive deviation) and antagonistic (negative deviation). An arbitrary classification scheme was proposed based on the magnitude of deviation (d) as: additive (50%, class-IV) antagonistic/synergistic. Naphthalene, n-butanol, o-xylene, catechol and p-cresol led to synergism in mixtures while 1, 2, 4-trimethylbenzene and 1, 3-dimethylnaphthalene contributed to antagonism. Most of the mixtures depicted additive or antagonistic effect. Synergism was prominent in some of the mixtures, such as, pulp and paper, textile dyes, and a mixture composed of polynuclear aromatic hydrocarbons. The organic chemical industry mixture depicted the highest abundance of antagonism and least synergism. Mixture toxicity was found to depend on partition coefficient, molecular connectivity index and relative concentration of the components.

  19. Comparative genomic and plasmid analysis of beer-spoiling and non-beer-spoiling Lactobacillus brevis isolates.

    Science.gov (United States)

    Bergsveinson, Jordyn; Ziola, Barry

    2017-12-01

    Beer-spoilage-related lactic acid bacteria (BSR LAB) belong to multiple genera and species; however, beer-spoilage capacity is isolate-specific and partially acquired via horizontal gene transfer within the brewing environment. Thus, the extent to which genus-, species-, or environment- (i.e., brewery-) level genetic variability influences beer-spoilage phenotype is unknown. Publicly available Lactobacillus brevis genomes were analyzed via BlAst Diagnostic Gene findEr (BADGE) for BSR genes and assessed for pangenomic relationships. Also analyzed were functional coding capacities of plasmids of LAB inhabiting extreme niche environments. Considerable genetic variation was observed in L. brevis isolated from clinical samples, whereas 16 candidate genes distinguish BSR and non-BSR L. brevis genomes. These genes are related to nutrient scavenging of gluconate or pentoses, mannose, and metabolism of pectin. BSR L. brevis isolates also have higher average nucleotide identity and stronger pangenome association with one another, though isolation source (i.e., specific brewery) also appears to influence the plasmid coding capacity of BSR LAB. Finally, it is shown that niche-specific adaptation and phenotype are plasmid-encoded for both BSR and non-BSR LAB. The ultimate combination of plasmid-encoded genes dictates the ability of L. brevis to survive in the most extreme beer environment, namely, gassed (i.e., pressurized) beer.

  20. Contribution of the activated catalase to oxidative stress resistance and γ-aminobutyric acid production in Lactobacillus brevis.

    Science.gov (United States)

    Lyu, Changjiang; Hu, Sheng; Huang, Jun; Luo, Maiqi; Lu, Tao; Mei, Lehe; Yao, Shanjing

    2016-12-05

    Lactic acid bacteria (LAB) are generally sensitive to H 2 O 2 , a compound which can paradoxically produce themselves and lead to the growth arrest and cell death. To counteract the potentially toxic effects of this compound, the gene katE encoding a heme-dependent catalase (CAT) belonging to the family of monofunctional CATs was cloned from Lactobacillus brevis CGMCC1306. The enhanced homologous CAT expression was achieved using the NICE system. L. brevis cells with overexpressed CAT showed 685-fold and 823-fold higher survival when exposed to 30mmol/L of H 2 O 2 and long-term aerated stress (after 72h), respectively, than that of the wild type cells. Furtherly, the effects of activated CAT on GABA production in L. brevis were investigated. A GABA production level of 66.4g/L was achieved using two-step biotransformation that successively employed the growing and resting cells derived from engineering L. brevis CAT. These results demonstrated clearly that overexpression of the KatE gene in L. brevis led to a marked increased survival in oxidizing environment, and shed light on a novel feasible approach to enhance the GABA production level by improving the antioxidative properties. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Measurement of natural radioactivity in chemical fertilizer and agricultural soil: evidence of high alpha activity.

    Science.gov (United States)

    Ghosh, Dipak; Deb, Argha; Bera, Sukumar; Sengupta, Rosalima; Patra, Kanchan Kumar

    2008-02-01

    People are exposed to ionizing radiation from the radionuclides that are present in different types of natural sources, of which phosphate fertilizer is one of the most important sources. Radionuclides in phosphate fertilizer belonging to 232Th and 238U series as well as radioisotope of potassium (40K) are the major contributors of outdoor terrestrial natural radiation. The study of alpha activity in fertilizers, which is the first ever in West Bengal, has been performed in order to determine the effect of the use of phosphate fertilizers on human health. The data have been compared with the alpha activity of different types of chemical fertilizers. The measurement of alpha activity in surface soil samples collected from the cultivated land was also performed. The sampling sites were randomly selected in the cultivated land in the Midnapore district, which is the largest district in West Bengal. The phosphate fertilizer is widely used for large agricultural production, mainly potatoes. The alpha activities have been measured using solid-state nuclear track detectors (SSNTD), a very sensitive detector for alpha particles. The results show that alpha activity of those fertilizer and soil samples varies from 141 Bq/kg to 2,589 Bq/kg and from 109 Bq/kg to 660 Bq/kg, respectively. These results were used to estimate environmental radiation exposure on human health contributed by the direct application of fertilizers.

  2. The Nature of the Interactions in Triethanolammonium-Based Ionic Liquids. A Quantum Chemical Study.

    Science.gov (United States)

    Fedorova, Irina V; Safonova, Lyubov P

    2018-05-10

    Structural features and interionic interactions play a crucial role in determining the overall stability of ionic liquids and their physicochemical properties. Therefore, we performed high-level quantum-chemical study of different cation-anion pairs representing the building units of protic ionic liquids based on triethanolammonium cation and anions of sulfuric, nitric, phosphoric, and phosphorus acids to provide essential insight into these phenomena at the molecular level. It was shown that every structure is stabilized through multiple H bonds between the protons in the N-H and O-H groups of the cation and different oxygen atoms of the anion acid. Using atoms in molecules topological parameters and natural bond orbital analysis, we determined the nature and strength of these interactions. Our calculations suggest that the N-H group of the cation has more proton donor-like character than the O-H group that makes the N-H···O hydrogen bonds stronger. A close relation between the binding energies of these ion pairs and experimental melting points was established: the smaller the absolute value of the binding energy between ions, the lower is the melting point.

  3. Physical and chemical characteristics of Vietnamese natural corals used as substitutes for bone grafts

    International Nuclear Information System (INIS)

    Tran Cong Toai; To Phuong Vu; Tran Bac Hai; Doan Binh

    1999-01-01

    Coral has been used as substitutes for bone grafts in France and the United State of American. In Vietnam, research on coral has been done at the Biomaterial Research Laboratory, The University Training Centre since 1994. Among the studies are the determination of physical and chemical characteristics of natural coral blocks obtained by the scientists of the NhaTrang Maritime Institute. We found that it was quite necessary to establish a standard formula for processing coral as biomaterial graft. The selected coral was cut into blocks approximately 1x1x1 cm or 1x1x2 cm and cleaned. We measured the density, porous rate, water loading speed (at room temperature and at boiled temperature with low pressure, mechanical strength and content of soluble protein, chitosan in coral rods. (1140 samples of three types of corals). The density of Porites australiensis was heavier than that of Porites lutea. But, Porites lutea has more porous rate than Porites australiensis. This experiment has also showed that mechanical strength of Porites australiensis was harder than that of Porites lutea. To measure the water loading speed, the coral rods were treated at boiled temperature with low pressure versus at room temperature. We found that the water loading speed of Porites australiensis at boiled temperature was faster than that at room temperature. Porites lutea and Montastrea annuligera showed as the same result. The efficiency of water loading rate is quite low approximately 116 - 121 % for 45 minutes at room temperature versus 135 - 155 % for only I 0 minutes at boiled temperature with low pressure. We measured the content of soluble protein by both Lowry and Biuret methods, the content of soluble protein after washing with 0.9% sodium chloride, 1210 degree C, 60 minutes is very low (below limit of tests). The content of chitosan from dried coral rods treated with HCI 36 - 38 % and NAOH 0.01N is about 0.1 - 0.6 %. Our study determined some physical and chemical characteristics

  4. IMPINGEMENT-SYNDROME OF PERONEUS BREVIS TENDON AFTER CALCANEAL FRACTURES (MORPHOLOGICAL ASPECTS

    Directory of Open Access Journals (Sweden)

    N. S. Konovalchuk

    2017-01-01

    Full Text Available Background. One of the main causes of pain in patients with consequences of calcaneal fractures is the lateral impingement syndrome. This term means lateral displacement of outer calcaneal wall at the moment of fracture, narrowing of anatomical space under the lateral malleolus and compression of soft tissues in this region, including tendons of short and long peroneal muscles. This leads to chronic traumatization of tendons, alteration of their normal tracking and development of tendinitis and tenosynovitis. At this moment there are no articles in foreign or Russian literature describing how prolonged traumatization influences the internal structure of the tendons. The purpose of this study was to evaluate the morphological changes in structure of peroneus brevis tendon after different duration of compression between outer wall of calcaneus and the tip of the lateral malleolus in patients with calcaneal malunion.Materials and methods. Fifteen patients with calcaneal malunion and lateral impingement syndrome were treated operatively between 2016 and 2017. To confirm the lateral impingement syndrome, the authors performed clinical examination and AP x-rays of ankle joint. Two peroneus brevis tendon specimens were obtained intraoperatively in each of 15 patients: one specimen from compressed and one from non-compressed area. Obtained specimens were histologically examined according to standard protocol.Results. Microscopically all specimens showed separation of collagen bundles with loose connective tissue degeneration, increase of vascularization and inflammation. The degree of these changes differed according to the compression duration. This allowed us to analyze the dynamics of these changes.Conclusion. The morphological changes in structure of peroneus brevis tendon during the compression between outer wall of calcaneus and the tip of the lateral malleolus correspond with dynamics of common pathologic reactions. Early stages showed signs of

  5. RESISTANCE TO THE ATTACK OF DRY-WOOD TERMITES (Cryptotermes brevis) OF SIX WOOD SPECIES

    OpenAIRE

    Fabrício Gomes Gonçalves; José Tarcísio da Silva Oliveira

    2006-01-01

    The dry wood termites are one of the largest causes of damages in wood used in Brazil. This work analyzed the attackof the Cryptotermes brevis in six commercials wood species in the north of the Rio de Janeiro and south of the Espírito Santo. The testobserved the number of holes, the percentage of died individuals and the damage of the pieces. When compared to the Pinus sp(reference), the species with less susceptibility to the attack were Cedrela fissilis, Cariocar brasiliense and Goupia gla...

  6. Hop resistance in the beer spoilage bacterium Lactobacillus brevis is mediated by the ATP-binding cassette multidrug transporter HorA

    NARCIS (Netherlands)

    Sakamoto, K; Margolles, A; van Veen, HW; Konings, WN

    Lactobacillus brevis is a major contaminant of spoiled beer. The organism can grow in beer in spite of the presence of antibacterial hop compounds that give the beer a bitter taste. The hop resistance in L. brevis is, at least in part, dependent on the expression of the horA gene. The deduced amino

  7. Chemical buffering in natural and engineered barrier systems: Thermodynamic constraints and performance assessment consequences

    International Nuclear Information System (INIS)

    Arthur, R.C.; Wei Zhou

    2000-12-01

    Thermodynamic and kinetic constraints on the chemical buffering properties of natural and engineered-barrier systems are derived in this study from theoretical descriptions, incorporated in the reaction-path model, of reversible and irreversible mass transfer in multicomponent, multiphase systems. The buffering properties of such systems are conditional properties because they refer to a specific aqueous species in a system that is open with respect to a specific reactant. The solution to a mathematical statement of this concept requires evaluation of the dependence of the activity of the buffered species on incremental changes in the overall reaction-progress variable. This dependence can be represented by a truncated Taylor's series expansion, where the values of associated derivatives are calculated using finite-difference techniques and mass-balance, charge-balance and mass-action constraints. Kinetic constraints on buffering behavior can also be described if the relation between reactant flux and reaction rate is well defined. This relation is explicit for the important case of advective groundwater flow and water-rock interaction. We apply the theoretical basis of the chemical buffering concept to processes that could affect the performance of a deep geologic repository for nuclear waste. Specifically, we focus on the likelihood that an inverse relation must exist between the buffer intensity and the migration velocity of reaction fronts in systems involving advective or diffusive mass transport. A quantitative understanding of this relation would provide the basis for evaluating the potential role of chemical buffering in achieving the isolation and retardation functions, of the EBS and geosphere in a KBS-3 repository. Our preliminary evaluation of this role considers the effects of chemical buffering on the propagation velocity of a pH front in both the near- and far field. We use a geochemical modeling technique compatible with the reaction-path model to

  8. Chemical characterisation of natural organic substrates for biological mitigation of acid mine drainage.

    Science.gov (United States)

    Gibert, Oriol; de Pablo, Joan; Luis Cortina, José; Ayora, Carlos

    2004-11-01

    The current approach of the biological treatment of acid mine drainage by means of a passive remediation system involves the choice of an appropriate organic substrate as electron donor for sulphate reducers. Nowadays this selection is one of the critical steps in the performance of such treatment, as this depends to a great extent on the degradability of the organic substrate. Thus, a prior characterisation of the organic substrate predicting its biodegradability would be desirable before embarking on an extensive large-scale application. The aim of this study was to correlate the chemical composition (lignin content) of four different natural organic substrates (compost, sheep and poultry manures, oak leaf) and their capacity to sustain bacterial activity in an attempt to predict biodegradation from chemical characterisation. The results showed that the lower the content of lignin in the organic substrate, the higher its biodegradability and capacity for developing bacterial activity. Of the four organic materials, sheep and poultry manures and oak leaf evolved reducing conditions and sustained active sulphidogenesis, which coupled with the decrease in sulphate concentration indicated bacterial activity. Sheep manure was clearly the most successful organic material as electron donor (sulphate removal >99%), followed by poultry manure and oak leaf (sulphate removal of 80%). Compost appeared to be too poor in carbon to promote sulphate-reducing bacteria activity by itself. Column experiments emphasised the importance of considering the residence time as a key factor in the performance of continuous systems. With a residence time of 0.73 days, sheep manure did not promote sulphidogenesis. However, extending residence time to 2.4 and 9.0 days resulted in an increase in the sulphate removal to 18% and 27%, respectively.

  9. Chemical buffering in natural and engineered barrier systems: Thermodynamic constraints and performance assessment consequences

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, R.C.; Wei Zhou [Monitor Scientific, LLC, Denver, CO (United States)

    2000-12-01

    Thermodynamic and kinetic constraints on the chemical buffering properties of natural and engineered-barrier systems are derived in this study from theoretical descriptions, incorporated in the reaction-path model, of reversible and irreversible mass transfer in multicomponent, multiphase systems. The buffering properties of such systems are conditional properties because they refer to a specific aqueous species in a system that is open with respect to a specific reactant. The solution to a mathematical statement of this concept requires evaluation of the dependence of the activity of the buffered species on incremental changes in the overall reaction-progress variable. This dependence can be represented by a truncated Taylor's series expansion, where the values of associated derivatives are calculated using finite-difference techniques and mass-balance, charge-balance and mass-action constraints. Kinetic constraints on buffering behavior can also be described if the relation between reactant flux and reaction rate is well defined. This relation is explicit for the important case of advective groundwater flow and water-rock interaction. We apply the theoretical basis of the chemical buffering concept to processes that could affect the performance of a deep geologic repository for nuclear waste. Specifically, we focus on the likelihood that an inverse relation must exist between the buffer intensity and the migration velocity of reaction fronts in systems involving advective or diffusive mass transport. A quantitative understanding of this relation would provide the basis for evaluating the potential role of chemical buffering in achieving the isolation and retardation functions, of the EBS and geosphere in a KBS-3 repository. Our preliminary evaluation of this role considers the effects of chemical buffering on the propagation velocity of a pH front in both the near- and far field. We use a geochemical modeling technique compatible with the reaction-path model

  10. Ultrasound improves chemical reduction of natural contaminant microbiota and Salmonella enterica subsp. enterica on strawberries.

    Science.gov (United States)

    do Rosário, Denes Kaic Alves; da Silva Mutz, Yhan; Peixoto, Jaqueline Moreira Curtis; Oliveira, Syllas Borburema Silva; de Carvalho, Raquel Vieira; Carneiro, Joel Camilo Souza; de São José, Jackline Freitas Brilhante; Bernardes, Patrícia Campos

    2017-01-16

    New sanitization methods have been evaluated to improve food safety and food quality and to replace chlorine compounds. However, these new methods can lead to physicochemical and sensory changes in fruits and vegetables. The present study evaluated the effects of acetic acid, peracetic acid, and sodium dodecylbenzenesulfonate isolated or combined with 5min of ultrasound treatment (40kHz, 500W) on strawberry quality over 9days of storage at 8°C. The strawberry natural contaminant microbiota (molds and yeasts, mesophilic aerobic and lactic acid bacteria), physicochemical quality (pH, total titratable acidity, total soluble solids, vitamin C, and color), sensory quality (triangle test) and inactivation of Salmonella enterica subsp. enterica intentionally inoculated onto strawberries were analyzed. Ultrasound increased the effect of all chemical compounds in the reduction of aerobic mesophilic, molds and yeasts. The best treatment for those groups of microorganisms was ultrasound combined with peracetic acid (US+PA) that reduced 1.8 and 2.0logcfu/g during 9days of storage. Bactericidal effect of peracetic acid was also improved by ultrasound inactivation of S. enterica, reaching a decimal reduction of 2.1logcfu/g. Moreover, synergistic effects were observed in contaminant natural microbiota inactivation for all tested compounds during storage, without any major physicochemical or sensory alteration to the strawberries. Therefore, ultrasound treatment can improve the effect of sanitizers that are substitutes of chlorine compounds without altering the quality of strawberries during storage. Acetic acid (PubChem CID: 176); Peracetic acid (PubChem CID: 6585); Sodium dodecylbenzenesulfonate (PubChem CID: 18372154). Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Phytoplankton blooms: an overlooked marine source of natural endocrine disrupting chemicals.

    Science.gov (United States)

    Gong, Yinhan; Wang, Xiaochong; Indran, Inthrani Raja; Zhang, Shi-Jun; Lv, Zhengbing; Li, Jun; Holmes, Michael; Tang, Ying Zhong; Yong, E L

    2014-09-01

    We had previously reported high androgenic and estrogenic activities in seawaters in confined clusters close to Singapore. Further investigations revealed a hitherto unsuspected link between estrogenic/androgenic activity and net phytoplankton count. The primary objective of this study was to investigate the cause of a correlation between net phytoplankton and endocrine activity, and corroborate this observation, and rule out other possible confounding factors. Our secondary objective was to study if these estrogenic secretions can impact human health. Five species of phytoplankton, Gymnodinium catenatum, Prorocentrum minimum, Alexandrium leei, Chattonella marina, and Fibrocapsa japonica, were isolated from Singapore waters and mass cultured and the cells and culture media screened for estrogenic and androgenic activity using human cell-based bioassays. The raphidophytes C. marina and F. japonica displayed significant estrogenic activity whilst the dinoflagellates G. catenatum and P. minimum displayed significant androgenic activity in both the cell extracts and the cell culture media extract. Our data shows that selected phytoplankton isolates are potent secretors of estrogenic and androgenic substances, which are potential endocrine disrupting chemicals (EDCs). As the harmful nature of EDCs is largely due to their bioaccumulation in the aquatic food chain our findings imply that the impact of these phytoplankton secretions needs to be investigated especially for seafoods, which are only a single trophic level away from phytoplankton. Alternatively, should these phytoplankton-origin EDCs not accumulate through marine food chains to significantly impact humans or marine mammals, our results indicate that functional assays could greatly over-estimate the risk from naturally occurring EDCs produced by marine phytoplankton. It remains to be determined if these EDCs affect zooplankton and other organisms that directly feed on marine phytoplankton, or if the secreted

  12. Screening and mutagenesis of lactobacillus brevis for biosynthesis of γ-aminobutyric acid

    International Nuclear Information System (INIS)

    Xia Jiang; Mei Lehe; Huang Jun

    2006-01-01

    γ-aminobutyric acid (GABA) is a major inhibitory neurotransmitter in the central nervous system. In this study, a GABA-producing strain, hjxj-01, was isolated from the milk samples and identified as Lactobacillus brevis. In this GYP medium containing sodium glutamate, the highest GABA concentration accumulated by Lactobacillus brevis hjxj-01 is 7 g/L. The strain was treated with UV and 60 Co γ-rays. Based on high positive mutation rate, the final mutagenesis conditions were UV light 30 W, irradiation distance 45 cm, irradiation time 50 s, and 60 Co γ-rays irradiation of 500 Gy. The mutant strain, hjxj-08119, was bred by GABA resistance selection. Cultured for 12 generations continually, the GABA-producing capacity of hjxj-08119 maintained stably. The fermentation results indicate that compared with the origin strain hjxj-01, the average yield of GABA by hjij-08119 is 17 g/L, which is 142.9% of the origin strain. (authors)

  13. In situ examination of Lactobacillus brevis after exposure to an oxidizing disinfectant

    Directory of Open Access Journals (Sweden)

    Yu eZhao

    2014-11-01

    Full Text Available Beer is a hostile environment for most microorganisms, but some lactic acid bacteria can grow in this environment. This is primarily because these organisms have developed the ability to grow in the presence of hops. It has been speculated that hop resistance is inversely correlated to resistance against oxidation, and this would have great impact on the use of various disinfectants in the brewing industry. In this study, we cultivated bacteria under aerobic and anaerobic conditions, and then investigated the in situ outgrowth of individual cells into microcolonies on MRS agar after exposure to the oxidizing agent peracetic acid (PAA. An automated microscope stage allowed us to analyse a much larger number of cells over extended periods of incubation. After PAA treatment, the lag time increased markedly, and extensive variation in morphology, µmax as well as stress resistance was observed between and within the tested L. brevis strains. The results suggest that aerobic cultivation increased the oxidative stress tolerance in L. brevis. The results also show that dead cells are randomly distributed in a microcolony and the majority of non-growing individual cells do not stain with a membrane impermanent dye (Propidium iodide, which indicates that PAA may not destroy the plasma membrane. In conclusion, the developed microscopic analysis of individual cells on MRS agar can provides faster results and more details of cell physiology compared to the traditional CFU method.

  14. Assessment of Application Technology of Natural User Interfaces in the Creation of a Virtual Chemical Laboratory

    Science.gov (United States)

    Jagodziński, Piotr; Wolski, Robert

    2015-02-01

    Natural User Interfaces (NUI) are now widely used in electronic devices such as smartphones, tablets and gaming consoles. We have tried to apply this technology in the teaching of chemistry in middle school and high school. A virtual chemical laboratory was developed in which students can simulate the performance of laboratory activities similar to those that they perform in a real laboratory. Kinect sensor was used for the detection and analysis of the student's hand movements, which is an example of NUI. The studies conducted found the effectiveness of educational virtual laboratory. The extent to which the use of a teaching aid increased the students' progress in learning chemistry was examined. The results indicate that the use of NUI creates opportunities to both enhance and improve the quality of the chemistry education. Working in a virtual laboratory using the Kinect interface results in greater emotional involvement and an increased sense of self-efficacy in the laboratory work among students. As a consequence, students are getting higher marks and are more interested in the subject of chemistry.

  15. Chemical nature of implant-derived titanium(IV) ions in synovial fluid

    International Nuclear Information System (INIS)

    Silwood, Christopher J.L.; Grootveld, Martin

    2005-01-01

    Previous investigations have indicated a deleterious leakage of Ti(III) and/or Ti(IV) species from Ti-Al-V alloy joint prostheses into adjacent tissue, synovium or synovial fluid (SF) in vivo. In view of the importance of the particular chemical nature of such complexes in determining their biological activity, we have employed high field proton ( 1 H) NMR spectroscopy to 'speciate' Ti(IV) in inflammatory SF. Treatment of osteoarthritic SF samples with increasing concentrations of Ti(IV) (0.10-1.03 mM [TiO(C 2 O 4 ) 2 ] 2- ) gave rise to a specific broadening of the citrate proton resonances, indicating that this bioavailable oxygen-donor ligand plays an important role in complexing implant-derived Ti(IV). 1 H NMR analysis of Ti(IV)-loaded SF samples subsequently treated with a large excess of ascorbate (0.05 M) showed that this added Ti(IV) chelator was only poorly effective in removing this metal ion from Ti(IV)-citrate/Ti(IV)-oxycitrate complexes. The results obtained here provide evidence for complexation of the low-molecular-mass (non-protein-bound) fraction of implant-derived Ti(IV) by citrate in vivo

  16. Radiated chemical reaction impacts on natural convective MHD mass transfer flow induced by a vertical cone

    Science.gov (United States)

    Sambath, P.; Pullepu, Bapuji; Hussain, T.; Ali Shehzad, Sabir

    2018-03-01

    The consequence of thermal radiation in laminar natural convective hydromagnetic flow of viscous incompressible fluid past a vertical cone with mass transfer under the influence of chemical reaction with heat source/sink is presented here. The surface of the cone is focused to a variable wall temperature (VWT) and wall concentration (VWC). The fluid considered here is a gray absorbing and emitting, but non-scattering medium. The boundary layer dimensionless equations governing the flow are solved by an implicit finite-difference scheme of Crank-Nicolson which has speedy convergence and stable. This method converts the dimensionless equations into a system of tri-diagonal equations and which are then solved by using well known Thomas algorithm. Numerical solutions are obtained for momentum, temperature, concentration, local and average shear stress, heat and mass transfer rates for various values of parameters Pr, Sc, λ, Δ, Rd are established with graphical representations. We observed that the liquid velocity decreased for higher values of Prandtl and Schmidt numbers. The temperature is boost up for decreasing values of Schimdt and Prandtl numbers. The enhancement in radiative parameter gives more heat to liquid due to which temperature is enhanced significantly.

  17. Natural and anthropogenic sources of chemical elements in sediment profiles from the Admiralty Bay, Antarctica

    International Nuclear Information System (INIS)

    Ribeiro, A.P.; Figueira, R.C.L.; Silva, C.R.A.; Franca, E.J.; Mahiques, M.M.; Bicego, M.C.; Montone, R.C.

    2010-01-01

    Full text: The Antarctic Continent and its surrounding Southern Ocean are the least known regions of the world, mainly due to the most unfavorable climatic conditions, in which sampling for environmental studies are quite difficult to be carried out. Admiralty Bay on the King George Island (Antarctica) hosts three research stations, Arctowski, Ferraz and Macchu Picchu, which are operate by Poland, Brazil and Peru, respectively. Therefore, human activities in this region require the use of fossil fuel as an energy source, which is also considered the main source of pollutants in the area. This work investigated the natural and anthropogenic inputs of chemical elements in sediment samples collected close to Ferraz Station, during the 25 th Brazilian Antarctica Expedition in the 2006/2007 austral summer. Total concentrations of As, Zn and Sc were determined in sediment profiles by using the Instrumental Neutron Activation Analysis (INAA). The analytical technique employed to determine the major elements such as Fe, Al, Ca, Mn and Ti was X-ray fluorescence (XRF) spectroscopy. For estimating the sedimentation rate, High Resolution Gamma Ray Spectrometry was applied to determine 137 Cs, after 30 days, to achieve secular equilibrium. According to the enrichment factor and the geochronology analysis, the most relevant enrichment was observed for As in the sediment samples, suggesting the increasing of its content due to the Brazilian activities in the Admiralty Bay. Despite some evidences of anthropogenic contribution, the study indicated low level of environmental risk for this region. (author)

  18. Removal of chemical oxygen demand from textile wastewater using a natural coagulant

    Energy Technology Data Exchange (ETDEWEB)

    Ramavandi, Bahman [Bushehr University of Medical Sciences, Bushehr (Iran, Islamic Republic of); Farjadfard, Sima [Islamic Azad University, Tehran (Iran, Islamic Republic of)

    2014-01-15

    A biomaterial was successfully synthesized from Plantago ovata by using an FeCl{sub 3}-induced crude extract (FCE). The potential of FCE to act as a natural coagulant was tested for the pretreatment of real textile wastewater. Tests were performed to evaluate the effects of FCE quantity, salt concentration, and wastewater pH on chemical oxygen demand (COD) reduction during a coagulation/flocculation process. Experimental results indicated that the wastewater could be effectively treated by using a coagulation/flocculation process, where the BOD{sub 5}/COD ratio of the effluent was improved to 0.48. A low coagulant dose, 1.5mg/L, achieved a high COD removal percentage, 89%, at operational conditions of neutral pH and room temperature. The experimental data revealed that the maximum COD removal occurred at water pH<8. Increasing the salt promoted the COD removal. The settling and filterability characteristics of the sludge were also studied. Scanning electron microscopy and energy dispersive spectroscopy studies were conducted to determine the sludge structure and composition, respectively. Overall, FCE as an eco-friendly biomaterial was revealed to be a very efficient coagulant and a promising option for the removal of COD from wastewaters.

  19. Resolving the chemical nature of nanodesigned silica surface obtained via a bottom-up approach.

    Science.gov (United States)

    Rahma, Hakim; Buffeteau, Thierry; Belin, Colette; Le Bourdon, Gwenaëlle; Degueil, Marie; Bennetau, Bernard; Vellutini, Luc; Heuzé, Karine

    2013-08-14

    The covalent grafting on silica surfaces of a functional dendritic organosilane coupling agent inserted, in a long alkyl chain monolayer, is described. In this paper, we show that depending on experimental parameters, particularly the solvent, it is possible to obtain a nanodesigned surface via a bottom-up approach. Thus, we succeed in the formation of both homogeneous dense monolayer and a heterogeneous dense monolayer, the latter being characterized by a nanosized volcano-type pattern (4-6 nm of height, 100 nm of width, and around 3 volcanos/μm(2)) randomly distributed over the surface. The dendritic attribute of the grafted silylated coupling agent affords enough anchoring sites to immobilize covalently functional gold nanoparticles (GNPs), coated with amino PEG polymer to resolve the chemical nature of the surfaces and especially the volcano type nanopattern structures of the heterogeneous monolayer. Thus, the versatile surface chemistry developed herein is particularly challenging as the nanodesign is straightforward achieved in a bottom-up approach without any specific lithography device.

  20. Geochemical properties and nuclear chemical characteristics of Oklo natural fission reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hidaka, Hiroshi [Hiroshima Univ., Higashi-Hiroshima (Japan). Faculty of Science

    1997-07-01

    There are six uranium deposits in the Gabonese Republic in the cnetral Africa. `Fission reactor zone`, the fission chain reactions generated about 200 billion years ago, was existed in a part of them. CEA begun geochemical researches of Oklo deposits etc. in 1991. The geochemical and nuclear chemical properties of Oklo were reviewed from the results of researches. Oklo deposits is consisted of main five sedimentary faces such as sandstone (FA), Black Shale formation (FB), mudstone (FC), tuff (FD) and volcaniclastic sandstone (FE) from the bottom on the base rock of granite in the Precambrian era. Uranium is enriched in the upper part of FA layer and the under part of FB layer. {sup 235}U/{sup 238}U, U content, fission proportion, duration time, neutron fluence, temperature, restitution factor of {sup 235}U and epithermal index ({gamma}) were investigated and compared. The geochemical properties of Oklo are as followed: large enrich of uranium, the abundance ratio of {sup 235}U as same as that of enriched uranium, interaction of natural water and small rear earth elements. These factors made casually Oklo fission reactor. (S.Y.)

  1. Characterization of the binding of the Ptychodiscus brevis neurotoxin T17 to sodium channels in rat brain synaptosomes

    Energy Technology Data Exchange (ETDEWEB)

    Poli, M.A.

    1985-01-01

    The lipid-soluble polyether neurotoxins isolated from the marine dinoflagellate Ptychodiscus brevis (formerly Gymnodinium breve) have been determined to bind to a unique receptor site associated with the voltage-sensitive sodium channel in rat brain synaptosomes. Reduction of the C/sub 42/ aldehyde function of T34 to the alcohol function of T17 using NaB/sup 3/H/sub 4/ yielded /sup 3/H-T17 with a specific activity of 15 Ci;/mmol. Using this specific probe, binding to sodium channels was measured at 4/sup 0/CC, 22/sup 0/C, and 37/sup 0/C. Rosenthal analysis of the binding data yielded a K/sub d/ of 2.9 nM and B/sub max/ of 6.8 pmoles /sup 3/H-T17 per mg of synaptosomal protein at 4/sup 0/C. Both K/sub d/ and B/sub max/ were found to be temperature dependent. Depolarization of the synaptosomes by osmotic lysis resulted in the loss of 34% of the available receptor sites, with no decrease in binding affinity. Unlabeled T17, T34, and synthetic T17 (reduced T34) were equipotent in their ability to displace /sup 3/H-T17 from its specific receptor site. Competition experiments using natural toxin probes specific for sites I-IV on the voltage-sensitive sodium channel demonstrate that /sup 3/H-T17 does not bind to any of the previously-described neurotoxin receptor sites. A fifth site is proposed.

  2. Chemical sensors in natural water: peculiarities of behaviour of chalcogenide glass electrodes for determination of copper, lead and cadmium ions

    International Nuclear Information System (INIS)

    Seleznev, B.L.; Legin, A.V.; Vlasov, Yu.G.

    1996-01-01

    Specific features of chemical sensors (chalcogenide glass and crystal ion-selective electrodes) behaviour have been studied to determine copper (2), lead, cadmium and fluorine in the course of in situ measurements, including long-term uninterrupted testing, for solving the problem of inspection over natural water contamination. 16 refs., 3 figs., 2 tabs

  3. Brevetoxin (PbTx-2) influences the redox status and NPQ of Karenia brevis by way of thioredoxin reductase.

    Science.gov (United States)

    Chen, Wei; Colon, Ricardo; Louda, J William; Del Rey, Freddy Rodriguez; Durham, Michaella; Rein, Kathleen S

    2018-01-01

    The Florida red tide dinoflagellate, Karenia brevis, is the major harmful algal bloom dinoflagellate of the Gulf of Mexico and plays a destructive role in the region. Blooms of K. brevis can produce brevetoxins: ladder-shaped polyether (LSP) compounds, which can lead to adverse human health effects, such as reduced respiratory function through inhalation exposure, or neurotoxic shellfish poisoning through consumption of contaminated shellfish. The endogenous role of the brevetoxins remains uncertain. Recent work has shown that some forms of NADPH dependent thioredoxin reductase (NTR) are inhibited by brevetoxin-2 (PbTx-2). The study presented herein reveals that high toxin and low toxin K. brevis, which have a ten-fold difference in toxin content, also show a significant difference in their ability, not only to produce brevetoxin, but also in their cellular redox status and distribution of xanthophyll cycle pigments. These differences are likely due to the inhibition of NTR by brevetoxin. The work could shed light on the physiological role that brevetoxin fills for K. brevis. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. BIOCHEMISTRY OF DINOFLAGELLATE LIPIDS, WITH PARTICULAR REFERENCE TO THE FATTY ACID AND STEROL COMPOSITION OF A KARENIA BREVIS BLOOM

    Science.gov (United States)

    Leblond, Jeffrey D., Terence J. Evens and Peter J. Chapman. 2003. Biochemistry of Dinoflagellate Lipids, with Particular Reference to the Fatty Acid and Sterol Composition of a Karenia brevis Bloom. Phycologia. 42(4):324-331. (ERL,GB 1160). The harmful marine dinoflagella...

  5. The mechanism of the tyrosine transporter TyrP supports a proton motive tyrosine decarboxylation pathway in Lactobacillus brevis

    NARCIS (Netherlands)

    Wolken, WAM; Lucas, PM; Lonvaud-Funel, A; Lolkema, JS; Wolken, Wout A.M.; Lucas, Patrick M.

    The tyrosine decarboxylase operon of Lactobacillus brevis IOEB9809 contains, adjacent to the tyrosine decarboxylase gene, a gene for TyrP, a putative tyrosine transporter. The two genes potentially form a proton motive tyrosine decarboxylation pathway. The putative tyrosine transporter gene of L.

  6. ECOHAB: Van Dolah_F- Karenia brevis Cell Cycle Analysis for Determination of In Situ Growth Rates (NODC Accession 0000538)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The reported growth rates of Karenia brevis vary from 0.2 to 0.5 divisions per day, both in laboratory and field populations observed. This growth rate alone is not...

  7. Isolation, structure elucidation and anticancer activity from Brevibacillus brevis EGS 9 that combats Multi Drug Resistant actinobacteria.

    Science.gov (United States)

    Arumugam, T; Senthil Kumar, P; Hemavathy, R V; Swetha, V; Karishma Sri, R

    2018-02-01

    Actinobacteria is the most widely distributed organism in the mangrove environment and produce a large amount of secondary metabolites. A new environmental actinobacterial stain exhibited strong antimicrobial activity against vancomycin and methicillin resistant actinobacteria. The active producer strain was found to be as Brevibacillus brevis EGS9, which was confirmed by its morphological, biochemical characteristics and 16S rRNA gene sequencing. It was deposited in NCBI GeneBank database and received with an accession number of KX388147. Brevibacillus brevis EGS9 was cultivated by submerged fermentation to produce antimicrobial compounds. The anti-proliferative agent was extracted from Brevibacillus brevis EGS9 with ethyl acetate. The bioactive metabolites of mangrove actinobacteria was identified by Liquid chromatography with mass spectrometry analysis. The result of the present investigation revealed that actinobacteria isolated from mangroves are potent source of anticancer activity. The strain of Brevibacillus brevis EGS9 exhibited a potential in vitro anticancer activity. The present research concluded that the actinobacteria isolated from mangrove soil sediment are valuable in discovery of novel species. Copyright © 2017. Published by Elsevier Ltd.

  8. Degs and degu operon from Bacillus-brevis: a combination that enhances the production of commercially valuable enzymes

    CSIR Research Space (South Africa)

    Louw, M

    1995-05-01

    Full Text Available A novel method has been developed for increasing the production of commercially valuable enzymes, such as proteases, beta-glucanases, alpha-amylases and levansucrase. It is dependent on two genes cloned from Bacillus brevis, expressed on a multicopy...

  9. Changes in chemical and microbiological parameters of some varieties of Sicily olives during natural fermentation

    Directory of Open Access Journals (Sweden)

    Romeo, Flora V.

    2006-12-01

    Full Text Available The changes and features of some olive cultivars during natural fermentation in brine were examined. The cultivars were typical of Sicily: “Nocellara messinese”, “Nocellara etnea”, “Moresca”, “Ogliarola” and “Tonda iblea”. The carpological data revealed their good quality. Chemical characteristics such as reducing sugars, titratable acidity, total phenols and dry matter were also investigated. The physical and chemical changes of olives and brines throughout the process time were monitored. Sodium chloride concentration was gradually increased from 5% (w/v to 6% after 60-75 days and 7% after 90. The olives were put in brine acidified up to pH = 4. The salt concentration and pH value were necessary to favor lactic fermentation. An uniform trend of pH was measured for all the olive cultivars: a stable pH under 4.5 value was measured. The course of titratable acidity measured in fermentation brines was in  agreement with the pH trend. The concentration of total phenols in flesh olives through the brine storage and fermentation is reported and the reduction of total phenols during the brine fermentation was fast in “Tonda iblea”, “Nocellara etnea” and “Moresca” olives.To measure the degree of oleuropein disappearance, the course of hydroxytyrosol in brine was monitored. Throughout the brining period, the growth of microbial populations was revealed on selective media: lactic acid bacteria, mesophilic microorganisms, yeasts and moulds.Los cambios y las características de algunas variedades de aceitunas han sido examinados durante la fermentación natural. Las variedades estudiadas fueron las típicas de Sicilia. Las determinaciones carpológicas revelan una buena calidad de los frutos. Las características químicas (azúcares, acidez, fenoles y materia seca han sido estudiadas. El cloruro de sodio en la salmuera se aumentó gradualmente del 5% al 6% después de 60-75 días y hasta 7% después de 90 días. Las

  10. Degradation of deicing chemicals affects the natural redox system in airfield soils.

    Science.gov (United States)

    Lissner, Heidi; Wehrer, Markus; Jartun, Morten; Totsche, Kai Uwe

    2014-01-01

    During winter operations at airports, large amounts of organic deicing chemicals (DIC) accumulate beside the runways and infiltrate into the soil during spring. To study the transport and degradation of DIC in the unsaturated zone, eight undisturbed soil cores were retrieved at Oslo airport, Norway, and installed as lysimeters at a nearby field site. Before snowmelt in 2010 and 2011, snow amended with a mix of the DICs propylene glycol (PG) and formate as well as bromide as conservative tracer was applied. Water samples were collected and analyzed until summer 2012. Water flow and solute transport varied considerably among the lysimeters but also temporally between 2010 and 2011. High infiltration rates during snowmelt resulted in the discharge of up to 51 and 82% PG in 2010 and 2011, respectively. The discharge of formate remained comparatively low, indicating its favored degradation even at freezing temperatures compared with PG. Manganese (Mn) and iron (Fe) were observed in the drainage in autumn owing to the anaerobic degradation of residual PG during summer. Our findings suggest that upper boundary conditions, i.e., snow cover and infiltration rate, and the extent of preferential flowpaths, control water flow and solute transport of bromide and PG during snowmelt. PG may therefore locally reach deeper soil regions where it may pose a risk for groundwater. In the long term, the use of DIC furthermore causes the depletion of potential electron acceptors and the transport of considerable amounts of Fe and Mn. To avoid an overload of the unsaturated zone with DIC and to maintain the natural redox system, the development of suitable remediation techniques is required.

  11. Effect of the chemical treatments on the characteristics of natural cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Sosiati, H., E-mail: hsosiati@ugm.ac.id [Nanomaterials Research Group, Integrated Research and Testing Laboratory (LPPT), Gadjah Mada University, Yogyakarta 55281 (Indonesia); Muhaimin, M.; Abdilah, P.; Wijayanti, D. A. [Department of Physics, Faculty of Mathematics and Natural of Sciences, Gadjah Mada University, Yogyakarta 55281 (Indonesia); Harsojo; Triyana, K. [Nanomaterials Research Group, Integrated Research and Testing Laboratory (LPPT), Gadjah Mada University, Yogyakarta 55281, Indonesia and Department of Physics, Faculty of Mathematics and Natural of Sciences, Gadjah Mada University, Yogyakarta 55281 (Indonesia)

    2014-09-25

    In order to characterize the morphology and size distribution of the cellulose fibers, natural cellulose from kenaf bast fibers was extracted using two chemical treatments; (1) alkali-bleaching-ultrasonic treatment and (2) alkali-bleaching-hydrolysis. Solutions of NaOH, H{sub 2}O{sub 2} and H{sub 2}SO{sub 4} were used for alkalization, bleaching and hydrolysis, respectively. The hydrolyzed fibers were centrifuged at a rotation speed of 10000 rpm for 10 min to separate the nanofibers from the microfibers. The separation was repeated in 7 steps by controlling pH of the solution in each step until neutrality was reached. Fourier transform infrared (FTIR) spectroscopy was performed on the fibers at the final step of each treatment: i.e. either ultrasonic treated- or hydrolyzed microfibers. Their FTIR spectra were compared with FTIR spectrum of a reference commercial α-cellulose. Changes in morphology and size distribution of the treated fibers were examined by scanning electron microscopy (SEM). FTIR spectra of ultrasonic treated- and hydrolyzed microfibers nearly coincided with the FTIR spectrum of commercial α-cellulose, suggesting successful extraction of cellulose. Ultrasonic treatment for 6 h resulted in a specific morphology in which cellulose nanofibers (≥100 nm) were distributed across the entire surface of cellulose microfibers (∼5 μm). Constant magnetic stirring combined with acid hydrolysis resulted in an inhomogeneous size distribution of both cellulose rods (500 nm-3 μm length, 100–200 nm diameter) and particles 100–200 nm in size. Changes in morphology of the cellulose fibers depended upon the stirring time; longer stirring time resulted in shorter fiber lengths.

  12. Effect of the chemical treatments on the characteristics of natural cellulose

    International Nuclear Information System (INIS)

    Sosiati, H.; Muhaimin, M.; Abdilah, P.; Wijayanti, D. A.; Harsojo; Triyana, K.

    2014-01-01

    In order to characterize the morphology and size distribution of the cellulose fibers, natural cellulose from kenaf bast fibers was extracted using two chemical treatments; (1) alkali-bleaching-ultrasonic treatment and (2) alkali-bleaching-hydrolysis. Solutions of NaOH, H 2 O 2 and H 2 SO 4 were used for alkalization, bleaching and hydrolysis, respectively. The hydrolyzed fibers were centrifuged at a rotation speed of 10000 rpm for 10 min to separate the nanofibers from the microfibers. The separation was repeated in 7 steps by controlling pH of the solution in each step until neutrality was reached. Fourier transform infrared (FTIR) spectroscopy was performed on the fibers at the final step of each treatment: i.e. either ultrasonic treated- or hydrolyzed microfibers. Their FTIR spectra were compared with FTIR spectrum of a reference commercial α-cellulose. Changes in morphology and size distribution of the treated fibers were examined by scanning electron microscopy (SEM). FTIR spectra of ultrasonic treated- and hydrolyzed microfibers nearly coincided with the FTIR spectrum of commercial α-cellulose, suggesting successful extraction of cellulose. Ultrasonic treatment for 6 h resulted in a specific morphology in which cellulose nanofibers (≥100 nm) were distributed across the entire surface of cellulose microfibers (∼5 μm). Constant magnetic stirring combined with acid hydrolysis resulted in an inhomogeneous size distribution of both cellulose rods (500 nm-3 μm length, 100–200 nm diameter) and particles 100–200 nm in size. Changes in morphology of the cellulose fibers depended upon the stirring time; longer stirring time resulted in shorter fiber lengths

  13. phisco-chemical studies concerning naturally occuring radiocuclides and heavy metal concentrations in groundwater

    International Nuclear Information System (INIS)

    Abd Allah, A.A.A.

    2011-01-01

    The present work is a comprehensive of drinking water quality from various rural regions of Egypt. People are living in these rural regions have a problem of scarcely water resources. They mainly depend on groundwater resources for drinking. These water resources may be contaminated with both naturally and/or industrial pollutants unexpected. In this study, several groundwater samples are obtained from certain regions in Egypt; physical, chemical and radiological parameters are examined. Then, compared to the standard limits values of the world health organization. A new modified ion exchange resin was prepared in our laboratory with a high efficiency factor which may be used for reducing the heavy metals that are being found in groundwater samples. The removal of heavy metals such as, Pb (II), Co (II) and Mn (II) ions was carried out by the modified ion exchange resin using Batch sorption experiments. The optimum condition of the removal efficiency was conducted under different parameters such as; effect of ph, initial ion concentrations, weight loaded and contact time to determine the optimum conditions for the resin function. Kinetic studies are performed using first and second order kinetic equations. The sorption kinetic experiments are found to be agreeing well with the second order kinetic equation. The particle diffusion model was also studied. three isotherm equations are applied for sorption of the investigated elements at equilibrium are well described by the Freundlich isotherm equation indicating that sorption process of those elements are applied with heterogeneous adsorption reaction. Dubinin and Radushkevich (D-R) isotherm equation is also applied. The free energy of the adsorption process is also given in the range of the ion exchange reaction.

  14. A Protein Disulfide Isomerase Gene Fusion Expression System That Increases the Extracellular Productivity of Bacillus brevis

    Science.gov (United States)

    Kajino, Tsutomu; Ohto, Chikara; Muramatsu, Masayoshi; Obata, Shusei; Udaka, Shigezo; Yamada, Yukio; Takahashi, Haruo

    2000-01-01

    We have developed a versatile Bacillus brevis expression and secretion system based on the use of fungal protein disulfide isomerase (PDI) as a gene fusion partner. Fusion with PDI increased the extracellular production of heterologous proteins (light chain of immunoglobulin G, 8-fold; geranylgeranyl pyrophosphate synthase, 12-fold). Linkage to PDI prevented the aggregation of the secreted proteins, resulting in high-level accumulation of fusion proteins in soluble and biologically active forms. We also show that the disulfide isomerase activity of PDI in a fusion protein is responsible for the suppression of the aggregation of the protein with intradisulfide, whereas aggregation of the protein without intradisulfide was prevented even when the protein was fused to a mutant PDI whose two active sites were disrupted, suggesting that another PDI function, such as chaperone-like activity, synergistically prevented the aggregation of heterologous proteins in the PDI fusion expression system. PMID:10653729

  15. Purification and properties of heat stable /alpha/-amylase from Bacillus brevis

    Energy Technology Data Exchange (ETDEWEB)

    Tsvetkov, V T; Emanuilova, E I

    1989-09-01

    An extracellular /alpha/-amylase has been isolated from a continuous culture of a thermophilic strain of Bacillus brevis. This enzyme was purified eightfold and obtained in electrophoretically homogenous form. The enzyme had a molecular weight of about 58 000, a pH optimum from 5.0 to 9.0 and a temperature optimum at 80/sup 0/C. The half-life of the purified enzyme in the presence of 5 mM CaCl/sub 2/ at 90/sup 0/C and pH 8.0 was 20 min. The K/sub m/ value for soluble starch was calculated to be 0.8 mg/ml. (orig.).

  16. RESISTANCE TO THE ATTACK OF DRY-WOOD TERMITES (Cryptotermes brevis OF SIX WOOD SPECIES

    Directory of Open Access Journals (Sweden)

    Fabrício Gomes Gonçalves

    2006-03-01

    Full Text Available The dry wood termites are one of the largest causes of damages in wood used in Brazil. This work analyzed the attackof the Cryptotermes brevis in six commercials wood species in the north of the Rio de Janeiro and south of the Espírito Santo. The testobserved the number of holes, the percentage of died individuals and the damage of the pieces. When compared to the Pinus sp(reference, the species with less susceptibility to the attack were Cedrela fissilis, Cariocar brasiliense and Goupia glabra, that alsopresented the largest percentages of mortality of termites. The Schizolobium parahyba, Toona ciliata and the Tachigalia myrmecophyllawere the species with the highest level of damage.

  17. Variant Branching Pattern of Dorsalis Pedis Artery Accompanied with Anomalous Presence of Extensor Hallucis Brevis Muscle

    Directory of Open Access Journals (Sweden)

    Ashwini Aithal Padur

    2017-10-01

    Full Text Available During routine dissection, we came across multiple variations in the dorsum of the right foot. Dorsalis pedis artery (DPA presented with an unusual branching pattern. The arcuate artery was completely absent, and hence three tarsal branches arose from lateral side of DPA. The first branch continued as first dorsal metatarsal artery, the second branch continued as the second dorsal metatarsal artery, and the third branch continued as third dorsal metatarsal artery which also provided a small twig to the fourth intermetatarsal space as the fourth dorsal metatarsal artery. We also observed the unique presence of extensor hallucis brevis muscle with the origin from the medial part of superior surface of the calcaneus and inserted to proximal phalanx of great toe. Since the DPA was just beneath this muscle, anomalous presence of the muscle may lead to compression of DPA. Awareness regarding such variations is critical for angiographers, vascular surgeons, reconstructive and plastic surgeons.

  18. Prediction of rodent carcinogenic potential of naturally occurring chemicals in the human diet using high-throughput QSAR predictive modeling

    International Nuclear Information System (INIS)

    Valerio, Luis G.; Arvidson, Kirk B.; Chanderbhan, Ronald F.; Contrera, Joseph F.

    2007-01-01

    Consistent with the U.S. Food and Drug Administration (FDA) Critical Path Initiative, predictive toxicology software programs employing quantitative structure-activity relationship (QSAR) models are currently under evaluation for regulatory risk assessment and scientific decision support for highly sensitive endpoints such as carcinogenicity, mutagenicity and reproductive toxicity. At the FDA's Center for Food Safety and Applied Nutrition's Office of Food Additive Safety and the Center for Drug Evaluation and Research's Informatics and Computational Safety Analysis Staff (ICSAS), the use of computational SAR tools for both qualitative and quantitative risk assessment applications are being developed and evaluated. One tool of current interest is MDL-QSAR predictive discriminant analysis modeling of rodent carcinogenicity, which has been previously evaluated for pharmaceutical applications by the FDA ICSAS. The study described in this paper aims to evaluate the utility of this software to estimate the carcinogenic potential of small, organic, naturally occurring chemicals found in the human diet. In addition, a group of 19 known synthetic dietary constituents that were positive in rodent carcinogenicity studies served as a control group. In the test group of naturally occurring chemicals, 101 were found to be suitable for predictive modeling using this software's discriminant analysis modeling approach. Predictions performed on these compounds were compared to published experimental evidence of each compound's carcinogenic potential. Experimental evidence included relevant toxicological studies such as rodent cancer bioassays, rodent anti-carcinogenicity studies, genotoxic studies, and the presence of chemical structural alerts. Statistical indices of predictive performance were calculated to assess the utility of the predictive modeling method. Results revealed good predictive performance using this software's rodent carcinogenicity module of over 1200 chemicals

  19. Role of plasmids in Lactobacillus brevis BSO 464 hop tolerance and beer spoilage.

    Science.gov (United States)

    Bergsveinson, Jordyn; Baecker, Nina; Pittet, Vanessa; Ziola, Barry

    2015-02-01

    Specific isolates of lactic acid bacteria (LAB) can grow in the harsh beer environment, thus posing a threat to brew quality and the economic success of breweries worldwide. Plasmid-localized genes, such as horA, horC, and hitA, have been suggested to confer hop tolerance, a trait required for LAB survival in beer. The presence and expression of these genes among LAB, however, do not universally correlate with the ability to grow in beer. Genome sequencing of the virulent beer spoilage organism Lactobacillus brevis BSO 464 revealed the presence of eight plasmids, with plasmids 1, 2, and 3 containing horA, horC, and hitA, respectively. To investigate the roles that these and the other five plasmids play in L. brevis BSO 464 growth in beer, plasmid curing with novobiocin was used to derive 10 plasmid variants. Multiplex PCRs were utilized to determine the presence or absence of each plasmid, and how plasmid loss affected hop tolerance and growth in degassed (noncarbonated) beer was assessed. Loss of three of the eight plasmids was found to affect hop tolerance and growth in beer. Loss of plasmid 2 (horC and 28 other genes) had the most dramatic effect, with loss of plasmid 4 (120 genes) and plasmid 8 (47 genes) having significant, but smaller, impacts. These results support the contention that genes on mobile genetic elements are essential for bacterial growth in beer and that beer spoilage ability is not dependent solely on the three previously described hop tolerance genes or on the chromosome of a beer spoilage LAB isolate.

  20. Experience with peroneus brevis muscle flaps for reconstruction of distal leg and ankle defects

    Directory of Open Access Journals (Sweden)

    Babu Bajantri

    2013-01-01

    Full Text Available Objective: Peroneus brevis is a muscle in the leg which is expendable without much functional deficit. The objective of this study was to find out its usefulness in coverage of the defects of the lower leg and ankle. Patients and Methods: A retrospective analysis of the use of 39 pedicled peroneus brevis muscle flaps used for coverage of defects of the lower leg and ankle between November 2010 and December 2012 was carried out. The flaps were proximally based for defects of the lower third of the leg in 12 patients and distally based for reconstruction of defects of the ankle in 26 patients, with one patient having flaps on both ankles. Results: Partial flap loss in critical areas was found in four patients requiring further flap cover and in non-critical areas in two patients, which were managed with a skin graft. Three of the four critical losses occurred when we used it for covering defects over the medial malleolus. There was no complete flap loss in any of the patients. Conclusion: This flap has a unique vascular pattern and fails to fit into the classification of the vasculature of muscles by Mathes and Nahai. The unusual feature is an axial vessel system running down the deep aspect of the muscle and linking the perforators from the peroneal artery and anterior tibial artery, which allows it to be raised proximally or distally on a single perforator. The flap is simple to raise and safe for the reconstruction of small-to moderate-sized skin defects of the distal third of the tibia and all parts of the ankle except the medial malleolus, which is too far from the pedicle of the distally based flap. The donor site can be closed primarily to provide a linear scar. The muscle flap thins with time to provide a good result aesthetically at the primary defect.

  1. Growth characteristics of Lactobacillus brevis KB290 in the presence of bile.

    Science.gov (United States)

    Kimoto-Nira, Hiromi; Suzuki, Shigenori; Suganuma, Hiroyuki; Moriya, Naoko; Suzuki, Chise

    2015-10-01

    Live Lactobacillus brevis KB290 have several probiotic activities, including immune stimulation and modulation of intestinal microbial balance. We investigated the adaptation of L. brevis KB290 to bile as a mechanism of intestinal survival. Strain KB290 was grown for 5 days at 37 °C in tryptone-yeast extract-glucose (TYG) broth supplemented with 0.5% sodium acetate (TYGA) containing 0.15%, 0.3%, or 0.5% bile. Growth was determined by absorbance at 620 nm or by dry weight. Growth was enhanced as the broth's bile concentration increased. Bile-enhanced growth was not observed in TYG broth or with xylose or fructose as the carbon source, although strain KB290 could assimilate these sugars. Compared with cells grown without bile, cells grown with bile had twice the cell yield (dry weight) and higher hydrophobicity, which may improve epithelial adhesion. Metabolite analysis revealed that bile induced more lactate production by glycolysis, thus enhancing growth efficiency. Scanning electron microscopy revealed that cells cultured without bile for 5 days in TYGA broth had a shortened rod shape and showed lysis and aggregation, unlike cells cultured for 1 day; cells grown with bile for 5 days had an intact rod shape and rarely appeared damaged. Cellular material leakage through autolysis was lower in the presence of bile than in its absence. Thus lysis of strain KB290 cells cultured for extended periods was suppressed in the presence of bile. This study provides new role of bile and sodium acetate for retaining an intact cell shape and enhancing cell yield, which are beneficial for intestinal survival. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. CHEMICALS

    CERN Multimedia

    Medical Service

    2002-01-01

    It is reminded that all persons who use chemicals must inform CERN's Chemistry Service (TIS-GS-GC) and the CERN Medical Service (TIS-ME). Information concerning their toxicity or other hazards as well as the necessary individual and collective protection measures will be provided by these two services. Users must be in possession of a material safety data sheet (MSDS) for each chemical used. These can be obtained by one of several means : the manufacturer of the chemical (legally obliged to supply an MSDS for each chemical delivered) ; CERN's Chemistry Service of the General Safety Group of TIS ; for chemicals and gases available in the CERN Stores the MSDS has been made available via EDH either in pdf format or else via a link to the supplier's web site. Training courses in chemical safety are available for registration via HR-TD. CERN Medical Service : TIS-ME :73186 or service.medical@cern.ch Chemistry Service : TIS-GS-GC : 78546

  3. Chemical composition and natural durability of juvenile and mature heartwood of Robinia pseudoacacia L.

    Directory of Open Access Journals (Sweden)

    João V.F Latorraca

    2011-09-01

    Full Text Available The aim of this study was to characterize the properties of juvenile and mature heartwood of Robinia pseudoacacia L. (black locust. The content, the composition, and subcellular localization of heartwood extractives were studied in 14 old-grown trees from forest sites in Germany and Hungary, as well as in 16 younger trees of four clone types. Heartwood extractives (methanol and acetone extraction were analysed by HPLC-chromatography. UV microspectrophotometry was used to localize the extractives in the wood cell walls. The natural durability of juvenile and mature heartwood was analysed according to the European standard EN 350-1. Growth analyses, as well as the chemical analyses, showed that in Robinia the formation of juvenile wood is restricted to the first 10-15 years of cambial growth. In the heartwood high contents of phenolic compounds and flavonoids were present, which were in high concentrations in the cell walls of the axial parenchyma and of the vessels. In the juvenile heartwood, the content of these extractives is significantly lower than in the mature heartwood. In agree, the juvenile heartwood had a lower resistance to decay by Coniophora puteana (brown rot fungus and Coriolus versicolor (white rot fungus compared to the mature.O objetivo deste estudo foi caracterizar as propriedades da região de cerne dos lenhos juvenis e adultos de Robinia pseudoacacia L. O conteúdo, a composição, bem como a localização subcelular dos extrativos foram estudados em 14 árvores de florestas de produção na Alemanha e na Hungria, assim como em 16 árvores de quatro tipos clone. Os extrativos (metanol e acetona extração foram analisados por cromatografia-HPLC. O microespectrofotômetro de ultra violeta foi utilizado para localizar os extrativos nas paredes celulares da madeira. A durabilidade natural do lenho juvenil e adulto foi analisada de acordo com a norma europeia EN 350-1. Análises do incremento, bem como as análises qu

  4. A new type of power energy for accelerating chemical reactions: the nature of a microwave-driving force for accelerating chemical reactions.

    Science.gov (United States)

    Zhou, Jicheng; Xu, Wentao; You, Zhimin; Wang, Zhe; Luo, Yushang; Gao, Lingfei; Yin, Cheng; Peng, Renjie; Lan, Lixin

    2016-04-27

    The use of microwave (MW) irradiation to increase the rate of chemical reactions has attracted much attention recently in nearly all fields of chemistry due to substantial enhancements in reaction rates. However, the intrinsic nature of the effects of MW irradiation on chemical reactions remains unclear. Herein, the highly effective conversion of NO and decomposition of H2S via MW catalysis were investigated. The temperature was decreased by several hundred degrees centigrade. Moreover, the apparent activation energy (Ea') decreased substantially under MW irradiation. Importantly, for the first time, a model of the interactions between microwave electromagnetic waves and molecules is proposed to elucidate the intrinsic reason for the reduction in the Ea' under MW irradiation, and a formula for the quantitative estimation of the decrease in the Ea' was determined. MW irradiation energy was partially transformed to reduce the Ea', and MW irradiation is a new type of power energy for speeding up chemical reactions. The effect of MW irradiation on chemical reactions was determined. Our findings challenge both the classical view of MW irradiation as only a heating method and the controversial MW non-thermal effect and open a promising avenue for the development of novel MW catalytic reaction technology.

  5. Combining polar organic chemical integrative samplers (POCIS) with toxicity testing to evaluate pesticide mixture effects on natural phototrophic biofilms

    International Nuclear Information System (INIS)

    Pesce, Stephane; Morin, Soizic; Lissalde, Sophie; Montuelle, Bernard; Mazzella, Nicolas

    2011-01-01

    Polar organic chemical integrative samplers (POCIS) are valuable tools in passive sampling methods for monitoring polar organic pesticides in freshwaters. Pesticides extracted from the environment using such methods can be used to toxicity tests. This study evaluated the acute effects of POCIS extracts on natural phototrophic biofilm communities. Our results demonstrate an effect of POCIS pesticide mixtures on chlorophyll a fluorescence, photosynthetic efficiency and community structure. Nevertheless, the range of biofilm responses differs according to origin of the biofilms tested, revealing spatial variations in the sensitivity of natural communities in the studied stream. Combining passive sampler extracts with community-level toxicity tests offers promising perspectives for ecological risk assessment. - Research highlights: → Polar organic chemical integrative samplers (POCIS) were used for monitoring polar organic pesticides in a contaminated river. → The acute effects of POCIS extracts were tested on natural phototrophic biofilm communities. → POCIS pesticide mixtures affected chlorophyll a fluorescence, photosynthetic efficiency and community structure. → Biofilm responses differed according to origin of the biofilms tested, revealing variations in the sensitivity of natural communities. → Combining passive sampler extracts with community-level toxicity tests offers promising perspectives for ecological risk assessment. - Pesticide mixtures extracted from POCIS can affect chl a fluorescence, photosynthetic efficiency and community structure of natural biofilms.

  6. Identifying the nature of surface chemical modification for directed self-assembly of block copolymers

    Directory of Open Access Journals (Sweden)

    Laura Evangelio

    2017-09-01

    Full Text Available In recent years, block copolymer lithography has emerged as a viable alternative technology for advanced lithography. In chemical-epitaxy-directed self-assembly, the interfacial energy between the substrate and each block copolymer domain plays a key role on the final ordering. Here, we focus on the experimental characterization of the chemical interactions that occur at the interface built between different chemical guiding patterns and the domains of the block copolymers. We have chosen hard X-ray high kinetic energy photoelectron spectroscopy as an exploration technique because it provides information on the electronic structure of buried interfaces. The outcome of the characterization sheds light onto key aspects of directed self-assembly: grafted brush layer, chemical pattern creation and brush/block co-polymer interface.

  7. Tuning the performance of a natural treatment process using metagenomics for improved trace organic chemical attenuation

    KAUST Repository

    Drewes, Jorg; Li, Dong; Regnery, Julia; Alidina, Mazahirali; Wing, Alexandredavid; Hoppe-Jones, Christiane

    2014-01-01

    removal of trace organic chemicals of emerging concern (CECs). Increasing the humic content of the primary substrate resulted in higher microbial diversity. Lower concentrations and a higher humic content of the primary substrate promoted the attenuation

  8. Oxidative regeneration of toluene-saturated natural zeolite by gaseous ozone: The influence of zeolite chemical surface characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Alejandro, Serguei [Laboratorio de Tecnologías Limpias (F. Ingeniería), Universidad Católica de la Santísima Concepción, Alonso de Ribera 2850, Concepción (Chile); Núcleo de Energías Renovables (F. Ingeniería), Universidad Católica de Temuco, Rudecindo Ortega 02950, Temuco (Chile); Valdés, Héctor, E-mail: hvaldes@ucsc.cl [Laboratorio de Tecnologías Limpias (F. Ingeniería), Universidad Católica de la Santísima Concepción, Alonso de Ribera 2850, Concepción (Chile); Manéro, Marie-Hélène [Université de Toulouse (France); INPT, UPS (France); Laboratoire de Génie Chimique, 4, Allée Emile Monso, F–31030 Toulouse (France); CNRS (France); Laboratoire de Génie Chimique, F–31030 Toulouse (France); Zaror, Claudio A. [Departamento de Ingeniería Química (F. Ingeniería), Universidad de Concepción, Concepción, Correo 3, Casilla 160–C (Chile)

    2014-06-01

    Highlights: • Surface acidity of modified natural zeolite is related to its chemical reactivity. • Brønsted acid sites are associated to toluene adsorption. • Lewis acid sites could decompose ozone generating surface active oxygen species. • Infrared spectra evidence active atomic oxygen and oxidation by-product formation. • 2NH4Z1 sample shows the highest reactivity toward adsorbed toluene. - Abstract: In this study, the effect of zeolite chemical surface characteristics on the oxidative regeneration of toluene saturated-zeolite samples is investigated. A Chilean natural zeolite (53% clinoptilolite, 40% mordenite and 7% quartz) was chemically modified by acid treatment with hydrochloric acid and by ion-exchange with ammonium sulphate. Thermal pre-treatments at 623 and 823 K were applied and six zeolite samples with different chemical surface characteristics were generated. Chemical modification of natural zeolite followed by thermal out-gassing allows distinguishing the role of acidic surface sites on the regeneration of exhausted zeolites. An increase in Brønsted acid sites on zeolite surface is observed as a result of ammonium-exchange treatment followed by thermal treatment at 623 K, thus increasing the adsorption capacity toward toluene. High ozone consumption could be associated to a high content of Lewis acid sites, since these could decompose ozone into atomic active oxygen species. Then, surface oxidation reactions could take part among adsorbed toluene at Brønsted acid sites and surface atomic oxygen species, reducing the amount of adsorbed toluene after the regenerative oxidation with ozone. Experimental results show that the presence of adsorbed oxidation by-products has a negative impact on the recovery of zeolite adsorption capacity.

  9. Oxidative regeneration of toluene-saturated natural zeolite by gaseous ozone: The influence of zeolite chemical surface characteristics

    International Nuclear Information System (INIS)

    Alejandro, Serguei; Valdés, Héctor; Manéro, Marie-Hélène; Zaror, Claudio A.

    2014-01-01

    Highlights: • Surface acidity of modified natural zeolite is related to its chemical reactivity. • Brønsted acid sites are associated to toluene adsorption. • Lewis acid sites could decompose ozone generating surface active oxygen species. • Infrared spectra evidence active atomic oxygen and oxidation by-product formation. • 2NH4Z1 sample shows the highest reactivity toward adsorbed toluene. - Abstract: In this study, the effect of zeolite chemical surface characteristics on the oxidative regeneration of toluene saturated-zeolite samples is investigated. A Chilean natural zeolite (53% clinoptilolite, 40% mordenite and 7% quartz) was chemically modified by acid treatment with hydrochloric acid and by ion-exchange with ammonium sulphate. Thermal pre-treatments at 623 and 823 K were applied and six zeolite samples with different chemical surface characteristics were generated. Chemical modification of natural zeolite followed by thermal out-gassing allows distinguishing the role of acidic surface sites on the regeneration of exhausted zeolites. An increase in Brønsted acid sites on zeolite surface is observed as a result of ammonium-exchange treatment followed by thermal treatment at 623 K, thus increasing the adsorption capacity toward toluene. High ozone consumption could be associated to a high content of Lewis acid sites, since these could decompose ozone into atomic active oxygen species. Then, surface oxidation reactions could take part among adsorbed toluene at Brønsted acid sites and surface atomic oxygen species, reducing the amount of adsorbed toluene after the regenerative oxidation with ozone. Experimental results show that the presence of adsorbed oxidation by-products has a negative impact on the recovery of zeolite adsorption capacity

  10. Oxidative regeneration of toluene-saturated natural zeolite by gaseous ozone: the influence of zeolite chemical surface characteristics.

    Science.gov (United States)

    Alejandro, Serguei; Valdés, Héctor; Manéro, Marie-Hélène; Zaror, Claudio A

    2014-06-15

    In this study, the effect of zeolite chemical surface characteristics on the oxidative regeneration of toluene saturated-zeolite samples is investigated. A Chilean natural zeolite (53% clinoptilolite, 40% mordenite and 7% quartz) was chemically modified by acid treatment with hydrochloric acid and by ion-exchange with ammonium sulphate. Thermal pre-treatments at 623 and 823K were applied and six zeolite samples with different chemical surface characteristics were generated. Chemical modification of natural zeolite followed by thermal out-gassing allows distinguishing the role of acidic surface sites on the regeneration of exhausted zeolites. An increase in Brønsted acid sites on zeolite surface is observed as a result of ammonium-exchange treatment followed by thermal treatment at 623K, thus increasing the adsorption capacity toward toluene. High ozone consumption could be associated to a high content of Lewis acid sites, since these could decompose ozone into atomic active oxygen species. Then, surface oxidation reactions could take part among adsorbed toluene at Brønsted acid sites and surface atomic oxygen species, reducing the amount of adsorbed toluene after the regenerative oxidation with ozone. Experimental results show that the presence of adsorbed oxidation by-products has a negative impact on the recovery of zeolite adsorption capacity. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Endocrine-Disrupting Chemicals and Oil and Natural Gas Operations: Potential Environmental Contamination and Recommendations to Assess Complex Environmental Mixtures.

    Science.gov (United States)

    Kassotis, Christopher D; Tillitt, Donald E; Lin, Chung-Ho; McElroy, Jane A; Nagel, Susan C

    2016-03-01

    Hydraulic fracturing technologies, developed over the last 65 years, have only recently been combined with horizontal drilling to unlock oil and gas reserves previously deemed inaccessible. Although these technologies have dramatically increased domestic oil and natural gas production, they have also raised concerns for the potential contamination of local water supplies with the approximately 1,000 chemicals that are used throughout the process, including many known or suspected endocrine-disrupting chemicals. We discuss the need for an endocrine component to health assessments for drilling-dense regions in the context of hormonal and antihormonal activities for chemicals used. We discuss the literature on a) surface and groundwater contamination by oil and gas extraction operations, and b) potential human exposure, particularly in the context of the total hormonal and antihormonal activities present in surface and groundwater from natural and anthropogenic sources; we also discuss initial analytical results and critical knowledge gaps. In light of the potential for environmental release of oil and gas chemicals that can disrupt hormone receptor systems, we recommend methods for assessing complex hormonally active environmental mixtures. We describe a need for an endocrine-centric component for overall health assessments and provide information supporting the idea that using such a component will help explain reported adverse health trends as well as help develop recommendations for environmental impact assessments and monitoring programs.

  12. [Research progress in chemical communication among insect-resistant genetically modified plants, insect pests and natural enemies].

    Science.gov (United States)

    Liu, Qing-Song; Li, Yun-He; Chen, Xiu-Ping; Peng, Yu-Fa

    2014-08-01

    Semiochemicals released by plants or insects play an important role in the communication among plants, phytophagous insects and their natural enemies. They thus form a chemical information network which regulates intra- and inter-specific behaviors and sustains the composition and structure of plant and insect communities. The application of insect-resistant genetically modified (IRGM) crops may affect the chemical communication within and among the tritrophic levels, and thus cause disturbances to the biotic community structure and the stability of the farmland ecosystem. This has raised concerns about the environmental safety of IRGM crops and triggered research worldwide. In the current article we provided a brief summary of the chemical communication among plants, herbivores and natural enemies; analyzed the potential of IRGM crops to affect the chemical communication between plants and arthropods and the related mechanisms; and discussed the current research progress and the future prospects in this field. We hope that this will promote the research in this field by Chinese scientists and increase our understanding of the potential effects of growing of IRGM crops on the arthropod community structure.

  13. Endocrine-disrupting chemicals and oil and natural gas operations: Potential environmental contamination and recommendations to assess complex environmental mixtures

    Science.gov (United States)

    Kassotis, Christopher D.; Tillitt, Donald E.; Lin, Chung-Ho; McElroy, Jane A.; Nagel, Susan C.

    2016-01-01

    Background: Hydraulic fracturing technologies, developed over the last 65 years, have only recently been combined with horizontal drilling to unlock oil and gas reserves previously deemed inaccessible. While these technologies have dramatically increased domestic oil and natural gas production, they have also raised concerns for the potential contamination of local water supplies with the approximately 1,000 chemicals used throughout the process, including many known or suspected endocrine-disrupting chemicals.Objectives: We discuss the need for an endocrine component to health assessments for drilling-dense regions in the context of hormonal and anti-hormonal activities for chemicals used.Methods: We discuss the literature on 1) surface and ground water contamination by oil and gas extraction operations, and 2) potential human exposure, particularly in context of the total hormonal and anti-hormonal activities present in surface and ground water from natural and anthropogenic sources, with initial analytical results and critical knowledge gaps discussed.Discussion: In light of the potential for environmental release of oil and gas chemicals that can disrupt hormone receptor systems, we recommend methods for assessing complex hormonally active environmental mixtures.Conclusions: We describe a need for an endocrine-centric component for overall health assessments and provide supporting information that using this may help explain reported adverse health trends as well as help develop recommendations for environmental impact assessments and monitoring programs.

  14. Methyl chloride via oxyhydrochlorination of methane: A building block for chemicals and fuels from natural gas. Environmental assessment

    International Nuclear Information System (INIS)

    1996-09-01

    DOE's natural gas mission, in partnership with its stakeholders, is to undertake and promote activities to maximize the Nation's ability to supply, transport, and use natural gas to encourage economic growth, enhance energy interests security, and improve the environment. In implementing this mission, DOE has been involved in promoting domestic natural gas as a clean, abundant, and reliable source of energy. In particular, DOE is interested in technologies capable of converting natural gas to other valuable resources, such as transportation fuels, hydrogen, and premium chemicals. The purpose of the proposed action is to further examine the potential of one such technology for natural gas conversion. Over the past five years, DOE's Pittsburgh Energy Technology Center has supported a research program to determine the feasibility of producing methyl chloride (CH 3 Cl), a key ingredient used in the silicone industry, directly from methane (the primary component of natural gas) via an oxyhydrochlorination (OHC) process. As a result of this research program the OHC process is now ready for further development. The proposed action would advance the OHC natural gas conversion technology to an integrated engineering-scale process at the Dow Corning plant in Carrollton, Kentucky

  15. Effect of natural and artificial drying of leaf biomassof Psidium guajava on the content and chemical composition of essential oil

    Directory of Open Access Journals (Sweden)

    Elizabeth Aparecida Josefi da Silva

    2016-10-01

    Full Text Available Psidium guajava L. is native to Central and South America. It is widely distributed and well adapted to Brazil, a producer of essential oils rich in terpenes. The objective of this study was to evaluate the effects of natural and artificial drying on the content and chemical composition of the essential oil of guava leaves (Psidium guajava L. grown in Rio Verde (GO. The two treatments consisted of drying fresh leaves either naturally in the shade or artificially at 40°C. Chemical composition was analyzed qualitatively and quantitatively by gas coupled with mass spectrometer chromatography (GC/MS and gas chromatography using a flame ionizer (GC-FID, respectively. The method of drying changed the content and chemical composition of the essential oil of guava leaves. Drying in the shade reduced the content and altered the constituents of the essential oil, whereas drying in an oven at 40°C, despite having reduced the amounts of the constituents, exhibited the highest essential oil content and increased the concentration of certain major constituents as compared to that in the natural shade drying method. The major components found in the essential oil of leaves regardless of the drying processes were trans-caryophyllene, ?-humulene, aromadendrene, ?-selinene, and selin-11-en-4?-ol. According to reports in the literature, these compounds possess fungicidal, insecticidal, antimicrobial, and anti-inflammatory activity, among others beneficial actions.

  16. High level heterologous protein production in Lactococcus and Lactobacillus using a new secretion system based on the Lactobacillus brevis S-layer signals.

    Science.gov (United States)

    Savijoki, K; Kahala, M; Palva, A

    1997-02-28

    A secretion cassette, based on the expression and secretion signals of a S-layer protein (SlpA) from Lactobacillus brevis, was constructed. E. coli beta-lactamase (Bla) was used as the reporter protein to determine the functionality of the S-layer signals for heterologous expression and secretion in Lactococcus lactis, Lactobacillus brevis, Lactobacillus plantarum, Lactobacillus gasseri and Lactobacillus casei using a low-copy-number plasmid derived from pGK12. In all hosts tested, the bla gene was expressed under the slpA signals and all Bla activity was secreted to the culture medium. The Lb. brevis S-layer promoters were very efficiently recognized in L. lactis, Lb. brevis and Lb. plantarum, whereas in Lb. gasseri the slpA promoter region appeared to be recognized at a lower level and in Lb. casei the level of transcripts was below the detection limit. The production of Bla was mainly restricted to the exponential phase of growth. The highest yield of Bla was obtained with L. lactis and Lb. brevis. Without pH control, substantial degradation of Bla occurred during prolonged cultivations with all lactic acid bacteria (LAB) tested. When growing L. lactis and Lb. brevis under pH control, the Bla activity could be stabilized also at the stationary phase. L. lactis produced up to 80 mg/l of Bla which to our knowledge represents the highest amount of a heterologous protein secreted by LAB so far. The short production phase implied a very high rate of secretion with a calculated value of 5 x 10(5) Bla molecules/cell per h. Such a high rate was also observed with Lb. plantarum, whereas in Lb. brevis the competition between the wild type slpA gene and the secretion construct probably lowered the rate of Bla production. The results obtained indicate wide applicability of the Lb. brevis slpA signals for efficient protein production and secretion in LAB.

  17. Natural background levels and threshold values of chemical species in three large-scale groundwater bodies in Northern Italy

    International Nuclear Information System (INIS)

    Molinari, Antonio; Guadagnini, Laura; Marcaccio, Marco; Guadagnini, Alberto

    2012-01-01

    We analyze natural background levels (NBLs) and threshold values (TVs) of spatially distributed chemical species (NH 4 , B and As) which may be a potential pressure and concern in three large scale alluvial and fluvio-deltaic aquifers at different depths of the Apennines and Po river plains in Emilia–Romagna, Northern Italy. Our results are based on statistical methodologies designed to separate the natural and anthropogenic contributions in monitored concentrations by modeling the empirical distribution of the detected concentration with a mixture of probability density functions. Available chemical observations are taken over a 20 years period and are associated with different depths and cover planar investigation scales of the order of hundreds of kilometers. High concentration values detected for NH 4 and B appear to be related to high natural background levels. Due to interaction with the host rock in different geochemical environments we observed that concentration vary in time and space (including in depth) consistently with the hydrogeochemical features and the occurrence of natural attenuation mechanisms in the analyzed reservoirs. Conversely, estimated As NBLs are not consistent with the conceptual model of the hydrogeochemical behavior of the systems analyzed and experimental evidences of As content in aquifer cores. This is due to the inability of these techniques to incorporate the complex dynamics of the processes associated with the specific hydrogeochemical setting. Statistical analyses performed upon aggregating the concentration data according to different time observation windows allow identifying temporal dynamics of NBLs and TVs of target compounds within the observation time frame. Our results highlight the benefit of a dynamic monitoring process and analysis of well demarcated groundwater bodies to update the associated NBLs as a function of the temporal dependence of natural processes occurring in the subsurface. Monitoring protocols could

  18. Natural background levels and threshold values of chemical species in three large-scale groundwater bodies in Northern Italy

    Energy Technology Data Exchange (ETDEWEB)

    Molinari, Antonio, E-mail: ant.molinari2002@libero.it [Politecnico di Milano, Dipartimento di Ingegneria Idraulica, Ambientale, Infrastrutture Viarie e Rilevamento, Piazza L. Da Vinci, 32-20133 Milano (Italy); Guadagnini, Laura [Politecnico di Milano, Dipartimento di Ingegneria Idraulica, Ambientale, Infrastrutture Viarie e Rilevamento, Piazza L. Da Vinci, 32-20133 Milano (Italy); Marcaccio, Marco [ARPA Emilia-Romagna, Direzione Tecnica, Largo Caduti del Lavoro, 6-40122 Bologna (Italy); Guadagnini, Alberto [Politecnico di Milano, Dipartimento di Ingegneria Idraulica, Ambientale, Infrastrutture Viarie e Rilevamento, Piazza L. Da Vinci, 32-20133 Milano (Italy)

    2012-05-15

    We analyze natural background levels (NBLs) and threshold values (TVs) of spatially distributed chemical species (NH{sub 4}, B and As) which may be a potential pressure and concern in three large scale alluvial and fluvio-deltaic aquifers at different depths of the Apennines and Po river plains in Emilia-Romagna, Northern Italy. Our results are based on statistical methodologies designed to separate the natural and anthropogenic contributions in monitored concentrations by modeling the empirical distribution of the detected concentration with a mixture of probability density functions. Available chemical observations are taken over a 20 years period and are associated with different depths and cover planar investigation scales of the order of hundreds of kilometers. High concentration values detected for NH{sub 4} and B appear to be related to high natural background levels. Due to interaction with the host rock in different geochemical environments we observed that concentration vary in time and space (including in depth) consistently with the hydrogeochemical features and the occurrence of natural attenuation mechanisms in the analyzed reservoirs. Conversely, estimated As NBLs are not consistent with the conceptual model of the hydrogeochemical behavior of the systems analyzed and experimental evidences of As content in aquifer cores. This is due to the inability of these techniques to incorporate the complex dynamics of the processes associated with the specific hydrogeochemical setting. Statistical analyses performed upon aggregating the concentration data according to different time observation windows allow identifying temporal dynamics of NBLs and TVs of target compounds within the observation time frame. Our results highlight the benefit of a dynamic monitoring process and analysis of well demarcated groundwater bodies to update the associated NBLs as a function of the temporal dependence of natural processes occurring in the subsurface. Monitoring

  19. Hydrogen production from natural gas using an iron-based chemical looping technology: Thermodynamic simulations and process system analysis

    International Nuclear Information System (INIS)

    Kathe, Mandar V.; Empfield, Abbey; Na, Jing; Blair, Elena; Fan, Liang-Shih

    2016-01-01

    Highlights: • Design of iron-based chemical looping process using moving bed for H_2 from CH_4. • Auto-thermal operation design using thermodynamic rationale for 90% carbon capture. • Cold gas efficiency: 5% points higher than Steam Methane Reforming baseline case. • Net thermal efficiency: 6% points higher than Steam Methane Reforming baseline case. • Sensitivity analysis: Energy recovery scheme, operating pressure, no carbon capture. - Abstract: Hydrogen (H_2) is a secondary fuel derived from natural gas. Currently, H_2 serves as an important component in refining operations, fertilizer production, and is experiencing increased utilization in the transportation industry as a clean combustion fuel. In recent years, industry and academia have focused on developing technology that reduces carbon emissions. As a result, there has been an increase in the technological developments for producing H_2 from natural gas. These technologies aim to minimize the cost increment associated with clean energy production. The natural gas processing chemical looping technology, developed at The Ohio State University (OSU), employs an iron-based oxygen carrier and a novel gas–solid counter-current moving bed reactor for H_2 production. Specifically, this study examines the theoretical thermodynamic limits for full conversion of natural gas through iron-based oxygen carrier reactions with methane (CH_4), by utilizing simulations generated with ASPEN modeling software. This study initially investigates the reducer and the oxidizer thermodynamic phase diagrams then derives an optimal auto-thermal operating condition for the complete loop simulation. This complete loop simulation is initially normalized for analysis on the basis of one mole of carbon input from natural gas. The H_2 production rate is then scaled to match that of the baseline study, using a full-scale ASPEN simulation for computing cooling loads, water requirements and net parasitic energy consumption. The

  20. Treatment of sugar beet thick juice spent wash by chemical and natural coagulants

    Directory of Open Access Journals (Sweden)

    Antov Mirjana G.

    2009-01-01

    Full Text Available The possibility of treatment of wastewater from bioethanol production by aluminium sulfate and natural coagulant extracted from common bean seed was studied. The highest coagulation activity at pH 6.5 is reached with analum dose of 1 g/l, but only a little lower coagulation activities were obtained by the dose of 0.05 and 0.10 g/l, which is more favorable for economic and environmental reasons. When natural coagulant from common bean was applied the highest coagulation activity, 14.3%, at pH 6.5 is reached with a dose of 0.5 ml/l. However, when common bean natural coagulant was used simultaneously with alum, the highest turbidity removal resulting in 24% coagulation activity was achieved and this was more efficient than when alum or natural coagulant were used.

  1. Investigation of surface properties of physico-chemically modified natural fibres using inverse gas chromatography

    CSIR Research Space (South Africa)

    Cordeiro, N

    2011-01-01

    Full Text Available Inverse gas chromatography (IGC) is a suitable method to determine surface energy of natural fibres when compared to wetting techniques. In the present study, the surface properties of raw and modified lignocellulosic fibres have been investigated...

  2. Magnesium carbide synthesis from methane and magnesium oxide - a potential methodology for natural gas conversion to premium fuels and chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, A.F.; Modestino, A.J.; Howard, J.B. [Massachusetts Institute of Technology, Cambridge, MA (United States)] [and others

    1995-12-31

    Diversification of the raw materials base for manufacturing premium fuels and chemicals offers U.S. and international consumers economic and strategic benefits. Extensive reserves of natural gas in the world provide a valuable source of clean gaseous fuel and chemical feedstock. Assuming the availability of suitable conversion processes, natural gas offers the prospect of improving flexibility in liquid fuels and chemicals manufacture, and thus, the opportunity to complement, supplement, or displace petroleum-based production as economic and strategic considerations require. The composition of natural gas varies from reservoir to reservoir but the principal hydrocarbon constituent is always methane (CH{sub 4}). With its high hydrogen-to-carbon ratio, methane has the potential to produce hydrogen or hydrogen-rich products. However, methane is a very chemically stable molecule and, thus, is not readily transformed to other molecules or easily reformed to its elements (H{sub 2} and carbon). In many cases, further research is needed to augment selectivity to desired product(s), increase single-pass conversions, or improve economics (e.g. there have been estimates of $50/bbl or more for liquid products) before the full potential of these methodologies can be realized on a commercial scale. With the trade-off between gas conversion and product selectivity, a major challenge common to many of these technologies is to simultaneously achieve high methane single-pass conversions and high selectivity to desired products. Based on the results of the scoping runs, there appears to be strong indications that a breakthrough has finally been achieved in that synthesis of magnesium carbides from MgO and methane in the arc discharge reactor has been demonstrated.

  3. Development of a propidium monoazide-polymerase chain reaction assay for detection of viable Lactobacillus brevis in beer.

    Science.gov (United States)

    Ma, Yanlin; Deng, Yang; Xu, Zhenbo; Liu, Junyan; Dong, Jianjun; Yin, Hua; Yu, Junhong; Chang, Zongming; Wang, Dongfeng

    The spoilage of beer by bacteria is of great concern to the brewer as this can lead to turbidity and abnormal flavors. The polymerase chain reaction (PCR) method for detection of beer-spoilage bacteria is highly specific and provides results much faster than traditional microbiology techniques. However, one of the drawbacks is the inability to differentiate between live and dead cells. In this paper, the combination of propidium monoazide (PMA) pretreatment and conventional PCR had been described. The established PMA-PCR identified beer spoilage Lactobacillus brevis based not on their identity, but on the presence of horA gene which we show to be highly correlated with the ability of beer spoilage LAB to grow in beer. The results suggested that the use of 30μg/mL or less of PMA did not inhibit the PCR amplification of DNA derived from viable L. brevis cells. The minimum amount of PMA to completely inhibit the PCR amplification of DNA derived from dead L. brevis cells was 2.0μg/mL. The detection limit of PMA-PCR assay described here was found to be 10 colony forming units (CFU)/reaction for the horA gene. Moreover, the horA-specific PMA-PCR assays were subjected to 18 reference isolates, representing 100% specificity with no false positive amplification observed. Overall the use of horA-specific PMA-PCR allows for a substantial reduction in the time required for detection of potential beer spoilage L. brevis and efficiently differentiates between viable and nonviable cells. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  4. Small angle X-ray scattering and transmission electron microscopy study of the Lactobacillus brevis S-layer protein

    Energy Technology Data Exchange (ETDEWEB)

    Jaeaeskelaeinen, Pentti [Department of Biomedical Engineering and Computational Science, PO Box 2200, FI-02015 Aalto University School of Science and Technology (Finland); Engelhardt, Peter [Haartman Institute, Department of Pathology, PO Box 21, FIN-00014 University of Helsinki (Finland); Hynoenen, Ulla; Palva, Airi [Department of Basic Veterinary Sciences, Division of Microbiology, FIN-00014 University of Helsinki (Finland); Torkkeli, Mika; Serimaa, Ritva, E-mail: ritva.serimaa@helsinki.f [Department of Physics, POB 64, 00014 University of Helsinki (Finland)

    2010-10-01

    The structure of self-assembly domain containing recombinant truncation mutants of Lactobacillus brevis surface layer protein SlpA in aqueous solution was studied using small-angle X-ray scattering and transmission electron microscopy. The proteins were found out to interact with each other forming stable globular oligomers of about 10 monomers. The maximum diameter of the oligomers varied between 75 A and 435 A.

  5. Variability of Ecosystem State in Rivers Containing Natural Dams: A Chemical Analysis

    Science.gov (United States)

    Reynolds, Z. A.

    2015-12-01

    Flooding, and the resulting economic damage to roads and property, is associated with natural dams such as beaver dams or log jams. For this reason, humans often remove natural dams; however, river reaches with natural dams provide very different ecosystem services in comparison with free-flowing river reaches. Therefore, the goal of this project is to assess the differences in ecosystem state between these different river reach types in the northeastern United States. We focused on differences in basic chemistry (e.g., dissolved oxygen, pH, temperature, and organic carbon) to assess the impact of natural dams on river ecosystem state. Study sites include rivers in the White Mountains and southeastern New Hampshire at locations with beaver dams, beaver ponds, beaver meadows, log jams, and free-flowing reaches. Dissolved oxygen, ORP, pH, temperature, and conductivity were measured in the field with a YSI Professional Plus meter. Water samples were collected for subsequent laboratory analysis of total organic carbon with a Shimadzu TOC-L. Preliminary results show that the chemistry of river water varies with feature type. Most significantly, dissolved oxygen concentrations are highest in free-flowing reaches and lowest in beaver ponds. Although beaver ponds are often associated with lower pH, due the increased concentration of organic acids, some beaver ponds can increase pH when compared to free-flowing reaches on the same river. Early results also show that water chemistry returns quickly to the chemistry typical of the free-flowing river reaches after being altered by a natural dam. Overall, natural dams create a river system that has more heterogeneity, and therefore has opportunities to provide more ecosystem functions, than a purely free-flowing river; this can increase the number of supported instream and riparian species. By increasing the understanding of how natural dams affect the chemistry of river water, river engineers can improve their decisions on how

  6. Characterization of a Potential Probiotic Lactobacillus brevis RK03 and Efficient Production of γ-Aminobutyric Acid in Batch Fermentation

    Directory of Open Access Journals (Sweden)

    Chien-Hui Wu

    2018-01-01

    Full Text Available Lactic acid bacteria were isolated from fish and evaluated for their γ-aminobutyric acid (GABA-producing abilities. Out of thirty-two isolates, Lactobacillus brevis RK03 showed the highest GABA production ability. The effects of various fermentation parameters including initial glutamic acid level, culture temperature, initial pH, and incubation time on GABA production were investigated via a singleparameter optimization strategy. For industrial large-scale production, a low-cost GABA producing medium (GM broth was developed for fermentation with L. brevis RK03. We found that an optimized GM broth recipe of 1% glucose; 2.5% yeast extract; 2 ppm each of CaCO3, MnSO4, and Tween 80; and 10 μM pyridoxal phosphate (PLP resulted in a maximum GABA yield of 62,523 mg/L after 88 h following the addition of 650 mM monosodium glutamate (MSG, for a conversion rate of 93.28%. Our data provide a practical approach for the highly efficient and economic production of GABA. In addition, L. brevis RK03 is highly resistant to gastric acid and bovine bile salt. Thus, the discovery of Lactobacillus strains with the ability to synthesize GABA may offer new opportunities in the design of improved health-promoting functional foods.

  7. Casein Hydrolysates by Lactobacillus brevis and Lactococcus lactis Proteases: Peptide Profile Discriminates Strain-Dependent Enzyme Specificity.

    Science.gov (United States)

    Bounouala, Fatima Zohra; Roudj, Salima; Karam, Nour-Eddine; Recio, Isidra; Miralles, Beatriz

    2017-10-25

    Casein from ovine and bovine milk were hydrolyzed with two extracellular protease preparations from Lactobacillus brevis and Lactococcus lactis. The hydrolysates were analyzed by HPLC-MS/MS for peptide identification. A strain-dependent peptide profile could be observed, regardless of the casein origin, and the specificity of these two proteases could be computationally ascribed. The cleavage pattern yielding phenylalanine, leucine, or tyrosine at C-terminal appeared both at L. lactis and Lb. brevis hydrolysates. However, the cleavage C-terminal to lysine was favored with Lb. brevis protease. The hydrolysates showed ACE-inhibitory activity with IC 50 in the 16-70 μg/mL range. Ovine casein hydrolysates yielded greater ACE-inhibitory activity. Previously described antihypertensive and opioid peptides were found in these ovine and bovine casein hydrolysates and prediction of the antihypertensive activity of the sequences based on quantitative structure and activity relationship (QSAR) was performed. This approach might represent a useful classification tool regarding health-related properties prior to further purification.

  8. Peroneus Brevis Attrition & Longitudinal Split Tear without Subluxation and Associated Hypertrophy of Peronal Tubercle" - Treatment of an Uncommon Lesion.

    Science.gov (United States)

    Tiwari, Mukesh; Singh, Varun; Bhargava, Rakesh

    2015-01-01

    Peroneus brevis tendinitis with its attritional longitudinal split rupture without any subluxation from peroneal groove and associated enlarged peroneal tubercle is un common presentation. A 40 year old female presented with moderate swelling and tenderness over the lateral and dorso-lateral aspect of left ankle with history of old trauma to ankle with swelling, persistant pain and difficulty in walking. On physical examination during passive eversion and inversion the excursion of the peroneal tendons was painful. Most tender point was just posterior to the tip of the fibula. During surgery we found the intact superior peroneal ligament with both peroneal tendons placed at normal site without subluxation, tendon sheath was inflamed and swollen, on further dissection we could see the attrition of inner surface of the peroneus brevis and a 2 cm longitudinal split tear of the same. Although rare but peroneus brevis tendon attrition and tear can occur without subluxation from peronal groove. Refractory ankle pain on lateral aspect presenting with on and off swelling should arise suspicion of peroneal tendon tear. Correct diagnosis and proper surgical repair can produce excellent results.

  9. Characterization of a Potential Probiotic Lactobacillus brevis RK03 and Efficient Production of γ-Aminobutyric Acid in Batch Fermentation.

    Science.gov (United States)

    Wu, Chien-Hui; Hsueh, Yi-Huang; Kuo, Jen-Min; Liu, Si-Jia

    2018-01-04

    Lactic acid bacteria were isolated from fish and evaluated for their γ-aminobutyric acid (GABA)-producing abilities. Out of thirty-two isolates, Lactobacillus brevis RK03 showed the highest GABA production ability. The effects of various fermentation parameters including initial glutamic acid level, culture temperature, initial pH, and incubation time on GABA production were investigated via a singleparameter optimization strategy. For industrial large-scale production, a low-cost GABA producing medium (GM) broth was developed for fermentation with L. brevis RK03. We found that an optimized GM broth recipe of 1% glucose; 2.5% yeast extract; 2 ppm each of CaCO₃, MnSO₄, and Tween 80; and 10 μM pyridoxal phosphate (PLP) resulted in a maximum GABA yield of 62,523 mg/L after 88 h following the addition of 650 mM monosodium glutamate (MSG), for a conversion rate of 93.28%. Our data provide a practical approach for the highly efficient and economic production of GABA. In addition, L. brevis RK03 is highly resistant to gastric acid and bovine bile salt. Thus, the discovery of Lactobacillus strains with the ability to synthesize GABA may offer new opportunities in the design of improved health-promoting functional foods.

  10. Trace metals partitioning among different sedimentary mineral phases and the deposit-feeding polychaete Armandia brevis

    International Nuclear Information System (INIS)

    Díaz-de-Alba, Margarita; Huerta-Diaz, Miguel Angel; Delgadillo-Hinojosa, Francisco; Hare, Landis; Galindo-Riaño, M. Dolores; Siqueiros-Valencia, Arturo

    2016-01-01

    Trace metals (Cd, Co, Cu, Fe, Mn, Ni, Pb, Zn) were determined in two operationally defined fractions (HCl and pyrite) in sediments from Ensenada and El Sauzal harbors (Mexico). The HCl fraction had significantly higher metal concentrations relative to the pyrite fraction in both harbors, underlining the weak tendency of most trace metals to associate with pyrite. Exceptionally, Cu was highly pyritized, with degrees of trace metal pyritization (DTMP) > 80% in both harbors. Dissolved Fe flux measurements combined with solid phase Fe sulfide data indicated that 98 mt of Fe are precipitated as iron sulfides every year in Ensenada Harbor. These Fe sulfides (and associated trace metals) will remain preserved in the sediments, unless they are perturbed by dredging or sediment resuspension. Calculations indicate that dredging activities could export to the open ocean 0.20 ± 0.13 to (0.30 ± 0.56) × 10"3 mt of Cd and Cu, respectively, creating a potential threat to marine benthic organisms. Degrees of pyritization (DOP) values in Ensenada and El Sauzal harbors were relatively low (< 25%) while degrees of sulfidization (DOS) were high (~ 50%) because of the contribution of acid volatile sulfide. DOP values correlated with DTMP values (p ≤ 0.001), indicating that metals are gradually incorporated into pyrite as this mineral is formed. Significant correlations were also found between DTMP values and − log(K_s_p_(_M_e_S_)/K_s_p_(_p_y_r_)) for both harbors, indicating that incorporation of trace metals into the pyrite phase is a function of the solubility product of the corresponding metal sulfide. The order in which elements were pyritized in both harbors was Zn ≈ Mn < Fe < Cd ≈ Pb < Ni ≈ Co < < Cu. Lastly, a strong correlation (r"2 = 0.87, p < 0.01) was found between average reactive trace metal concentrations and metal concentrations measured in Armandia brevis (a deposit-feeding Opheliid polychaete), suggesting that these labile sedimentary metals are

  11. Trace metals partitioning among different sedimentary mineral phases and the deposit-feeding polychaete Armandia brevis

    Energy Technology Data Exchange (ETDEWEB)

    Díaz-de-Alba, Margarita [Department of Analytical Chemistry, Institute of Biomolecules (INBIO), Faculty of Sciences, CEI-MAR, University of Cadiz, Campus Rio S. Pedro, E-11510, Puerto Real, Cadiz (Spain); Huerta-Diaz, Miguel Angel, E-mail: huertam@uabc.edu.mx [Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Campus Ensenada, Km. 103 Carr. Tijuana-Ensenada, Ensenada 22800, Baja California (Mexico); Delgadillo-Hinojosa, Francisco [Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Campus Ensenada, Km. 103 Carr. Tijuana-Ensenada, Ensenada 22800, Baja California (Mexico); Hare, Landis [Centre Eau Terre Environnement, 490, rue de la Couronne, Québec, Québec G1K 9A9 (Canada); Galindo-Riaño, M. Dolores [Department of Analytical Chemistry, Institute of Biomolecules (INBIO), Faculty of Sciences, CEI-MAR, University of Cadiz, Campus Rio S. Pedro, E-11510, Puerto Real, Cadiz (Spain); Siqueiros-Valencia, Arturo [Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Campus Ensenada, Km. 103 Carr. Tijuana-Ensenada, Ensenada 22800, Baja California (Mexico)

    2016-02-01

    Trace metals (Cd, Co, Cu, Fe, Mn, Ni, Pb, Zn) were determined in two operationally defined fractions (HCl and pyrite) in sediments from Ensenada and El Sauzal harbors (Mexico). The HCl fraction had significantly higher metal concentrations relative to the pyrite fraction in both harbors, underlining the weak tendency of most trace metals to associate with pyrite. Exceptionally, Cu was highly pyritized, with degrees of trace metal pyritization (DTMP) > 80% in both harbors. Dissolved Fe flux measurements combined with solid phase Fe sulfide data indicated that 98 mt of Fe are precipitated as iron sulfides every year in Ensenada Harbor. These Fe sulfides (and associated trace metals) will remain preserved in the sediments, unless they are perturbed by dredging or sediment resuspension. Calculations indicate that dredging activities could export to the open ocean 0.20 ± 0.13 to (0.30 ± 0.56) × 10{sup 3} mt of Cd and Cu, respectively, creating a potential threat to marine benthic organisms. Degrees of pyritization (DOP) values in Ensenada and El Sauzal harbors were relatively low (< 25%) while degrees of sulfidization (DOS) were high (~ 50%) because of the contribution of acid volatile sulfide. DOP values correlated with DTMP values (p ≤ 0.001), indicating that metals are gradually incorporated into pyrite as this mineral is formed. Significant correlations were also found between DTMP values and − log(K{sub sp(MeS)}/K{sub sp(pyr)}) for both harbors, indicating that incorporation of trace metals into the pyrite phase is a function of the solubility product of the corresponding metal sulfide. The order in which elements were pyritized in both harbors was Zn ≈ Mn < Fe < Cd ≈ Pb < Ni ≈ Co < < Cu. Lastly, a strong correlation (r{sup 2} = 0.87, p < 0.01) was found between average reactive trace metal concentrations and metal concentrations measured in Armandia brevis (a deposit-feeding Opheliid polychaete), suggesting that these labile sedimentary metals are

  12. Lactobacillus brevis-based bioingredient inhibits Aspergillus niger growth on pan bread

    Directory of Open Access Journals (Sweden)

    Mariaelena Di Biase

    2014-11-01

    Full Text Available Bread shelf life is generally compromised by fungi mainly belonging to Aspergillus and Penicillium genera, which colonise the surface of the product within few days from the production. The aim of this study was to select a Lactobacillus brevis-based bioingredient (LbBio able to inhibit the growth of Aspergillus niger ITEM5132 on pan bread in order to prolong its shelf life. Four LbBio formulations, obtained by growing a selected L. brevis strain in a flour-based medium containing different carbon sources or acid precursors (fructose, LbBio1; fructose and maltose, LbBio2; α-chetoglutaric acid, LbBio3; short-chain fructooligosaccharides, LbBio4, were evaluated for their content of organic acids (lactic, acetic, propionic, phenyllactic, 4-hydroxy-phenyllactic, valeric, isovaleric acids. The LbBio formulations were applied in yeast-leavened bread during bread-making trials and the resulting products were inoculated after baking with A. niger spore’s suspension and the fungal growth was monitored during storage (25°C for 6 days. The formulation showing the highest inhibitory activity was separated by ultra-filtration method, and whole and fractions obtained were evaluated for their in vitro activity. The fraction showing the highest activity was further separated by gel-filtration and the resulting products were investigated for their protein content and in vitro inhibition. The results from the bread-making trials performed using different formulations of LbBio showed a delay in fungal growth (1 day respect to the bread not containing the bioingredient (control or including calcium propionate (0.3% w/w. The formulation LbBio2, prepared with fructose and maltose 1% (w/vol, contained the highest amount of total organic acids, including phenyllactic and hydroxyl-phenyllactic acids, and reduced the visual spoilage of bread. This formulation was separated by ultra-filtration and fractions containing metabolites with molecular weight higher than 30 k

  13. Structure and chemical characteristics of natural mineral deposit Terbunskaya (Lipetsk region, Russia)

    Energy Technology Data Exchange (ETDEWEB)

    Motyleva, S., E-mail: motyleva-svetlana@mail.ru; Mertvishcheva, M. [All-Russian Horticular Institute for Breeding, Agrotechnology and Nursery Russian Academy of Agricultural Sciences, Moskow (Russian Federation); Shchuchka, R.; Gulidova, V. [Yelets state university named after I. A. Bunin, Yelets (Russian Federation)

    2015-07-22

    New knowledge about the mineralogical features Terbunsky mineral. Investigated 5 fractions isolated from the incision (2-2,5 m). Terbunskaya deposit belongs to minerals Santonian age. Scanning electron microscopy and energy dispersive analysis of fractions isolated studied in detail. In the coarse fractions found ancient organic remains of algae and micro-organisms that have been sedimented together with the mineral component during geological periods. The share of organic inclusions does not exceed 1.5%. Chemical composition confirms the presence of silicon and carbonate organisms. Advantageously proportion of minerals having a layered structure with a plurality of micro and nano pore size 600 - 80-nm and an average chemical composition (wt%): Na (0,64), Mg (0,54), Al (13.48), Si (27 57), K (2.39) Ca (0.75)

  14. Natural gas to liquid transportation fuels and chemicals via the Sasol synthol process

    International Nuclear Information System (INIS)

    Fourie, J.H.

    1992-01-01

    This paper deals with the recent developments in Synfuels technology at Sasol. The specific areas covered are synthesis plants and the development of modern high technology reactors to reduce capital and maintenance costs of future Synfuel plants. Emphasis is further placed on the co-production of chemicals in Synfuel plants to increase profitability. An important aspect namely that the fuels from the Sasol Synthol process can meet the new specifications for reformulated gasoline are also dealt with in the paper

  15. Treatment of sugar beet thick juice spent wash by chemical and natural coagulants

    OpenAIRE

    Antov Mirjana G.; Klašnja Mile T.; Šćiban Marina B.

    2009-01-01

    The possibility of treatment of wastewater from bioethanol production by aluminium sulfate and natural coagulant extracted from common bean seed was studied. The highest coagulation activity at pH 6.5 is reached with analum dose of 1 g/l, but only a little lower coagulation activities were obtained by the dose of 0.05 and 0.10 g/l, which is more favorable for economic and environmental reasons. When natural coagulant from common bean was applied the highest coagulation activity, 14.3%, at pH ...

  16. Evaluation of reduced chemical kinetic mechanisms used for modeling mild combustion for natural gas

    Directory of Open Access Journals (Sweden)

    Hamdi Mohamed

    2009-01-01

    Full Text Available A numerical and parametric study was performed to evaluate the potential of reduced chemistry mechanisms to model natural gas chemistry including NOx chemistry under mild combustion mode. Two reduced mechanisms, 5-step and 9-step, were tested against the GRI-Mech3.0 by comparing key species, such as NOx, CO2 and CO, and gas temperature predictions in idealized reactors codes under mild combustion conditions. It is thus concluded that the 9-step mechanism appears to be a promising reduced mechanism that can be used in multi-dimensional codes for modeling mild combustion of natural gas.

  17. Contribution to the study of the new international philosophy of the radiological safety in the natural uranium chemical treatment

    International Nuclear Information System (INIS)

    Moraes da Silva, T. de

    1990-01-01

    The objective of this work is to adapt the Radiological Safety System in the facilities concerned to the chemical treatment of the uranium concentrated (yellow-cake) until conversion in uranium hexafluoride in the pilot plant of IPEN-CNEN/SP, to the new international philosophy adopted by ICRP and IAEA. The new philosophy changes fully the Radiological Protection concepts of preceding philosophy, changes, also, the concept of the workplace and individual monitoring as well as the classification of the working areas. In this paper we show the monitoring program, in each phase of the natural uranium treatment chemical process in conversion facility for external irradiation, surface contamination and air contamination. The results were analysed according with the new philosophy and used to reclassify the workplace. It was introduced the condition work concept taking account the time spent by the worker in that workplace. (author)

  18. Study contribution to the new international philosophy of the radiological safety system on chemical processing of the natural uranium

    International Nuclear Information System (INIS)

    Silva, T.M. da.

    1988-01-01

    The objective of the work is to adapt the radiological Safety System in the facilities concerned to the chemical treatment of the uranium concentrated (yellow-cake) until conversion in uranium hexafluoride in the pilot plant of IPEN-CNEN/SP, to the new international philosophy adopted by the International Commission Radiological on Protection ICPR publication 22(1973), 26(1977), 30(1978) and the International Atomic Energy Agency IAEA publication 9(1982). The new philosophy changes fully the Radiological Protection concepts of preceding philosophy, changes, also, the concept of the work place and individual monitoring as well as the classification of the working areas. These new concepts are applied in each phase of the natural uranium treatment chemical process in conversion facility. (author)

  19. Perturbing dissimilar biomolecular targets from natural product scaffolds and focused chemical decoration

    DEFF Research Database (Denmark)

    Nielsen, John; Tung, Truong Thanh; Tim, Holm Jakobsen

    agents. On first attempt, by screening natural product sources we have successfully discovered that curcuminoids as potent inhibitors of p-type ATPases from diverse kingdoms of life including Pma1. On other attempt, the fungal metabolite fusaric acid was reported to reduce stomatal conductance in banana...

  20. METHANE EMISSIONS FROM THE NATURAL GAS INDUSTRY VOLUME 13: CHEMICAL INJECTION PUMPS

    Science.gov (United States)

    The 15-volume report summarizes the results of a comprehensive program to quantify methane (CH4) emissions from the U.S. natural gas industry for the base year. The objective was to determine CH4 emissions from the wellhead and ending downstream at the customer's meter. The accur...

  1. Chitosan-Starch Films with Natural Extracts: Physical, Chemical, Morphological and Thermal Properties

    Directory of Open Access Journals (Sweden)

    Jessica I. Lozano-Navarro

    2018-01-01

    Full Text Available The aim of this study is to analyze the properties of a series of polysaccharide composite films, such as apparent density, color, the presence of functional groups, morphology, and thermal stability, as well as the correlation between them and their antimicrobial and optical properties. Natural antioxidants such as anthocyanins (from cranberry; blueberry and pomegranate; betalains (from beetroot and pitaya; resveratrol (from grape; and thymol and carvacrol (from oregano were added to the films. Few changes in the position and intensity of the FTIR spectra bands were observed despite the low content of extract added to the films. Due to this fact, the antioxidants were extracted and identified by spectroscopic analysis; and they were also quantified using the Folin-Denis method and a gallic acid calibration curve, which confirmed the presence of natural antioxidants in the films. According to the SEM analysis, the presence of natural antioxidants has no influence on the film morphology because the stretch marks and white points that were observed were related to starch presence. On the other hand, the TGA analysis showed that the type of extract influences the total weight loss. The overall interpretation of the results suggests that the use of natural antioxidants as additives for chitosan-starch film preparation has a prominent impact on most of the critical properties that are decisive in making them suitable for food-packing applications.

  2. Chitosan-Starch Films with Natural Extracts: Physical, Chemical, Morphological and Thermal Properties

    Science.gov (United States)

    Díaz-Zavala, Nancy P.; Melo-Banda, José A.; García-Alamilla, Ricardo; Martínez-Hernández, Ana L.; Zapién-Castillo, Samuel

    2018-01-01

    The aim of this study is to analyze the properties of a series of polysaccharide composite films, such as apparent density, color, the presence of functional groups, morphology, and thermal stability, as well as the correlation between them and their antimicrobial and optical properties. Natural antioxidants such as anthocyanins (from cranberry; blueberry and pomegranate); betalains (from beetroot and pitaya); resveratrol (from grape); and thymol and carvacrol (from oregano) were added to the films. Few changes in the position and intensity of the FTIR spectra bands were observed despite the low content of extract added to the films. Due to this fact, the antioxidants were extracted and identified by spectroscopic analysis; and they were also quantified using the Folin-Denis method and a gallic acid calibration curve, which confirmed the presence of natural antioxidants in the films. According to the SEM analysis, the presence of natural antioxidants has no influence on the film morphology because the stretch marks and white points that were observed were related to starch presence. On the other hand, the TGA analysis showed that the type of extract influences the total weight loss. The overall interpretation of the results suggests that the use of natural antioxidants as additives for chitosan-starch film preparation has a prominent impact on most of the critical properties that are decisive in making them suitable for food-packing applications. PMID:29329275

  3. Ecopharmacognosy: Exploring The Chemical And Biological Potential Of Nature For Human Health

    Directory of Open Access Journals (Sweden)

    Geoffrey A. Cordell

    2014-04-01

    Full Text Available “Why didn’t they develop natural product drugs in a sustainable manner at the beginning of this century?”  In 2035, when about 10.0 billion will inhabit Earth, will this be our legacy as the world contemplates the costs and availability of synthetic and gene-based products for primary health care?  Acknowledging the recent history of the relationship between humankind and the Earth, it is essential that the health care issues being left for our descendants be considered in terms of resources. For most people in the world, there are two vast health care “gaps”, access to quality drugs and the development of drugs for major global and local diseases.  Consequently for all of these people, plants, in their various forms, remain a primary source of health care.  In the developed countries, natural products derived from plants assume a relatively minor role in health care, as prescription and over-the-counter products, even with the widespread use of phytotherapeutical preparations.  Significantly, pharmaceutical companies have retrenched substantially in their disease areas of focus.  These research areas do not include the prevalent diseases of the middle- and lower-income countries, and important diseases of the developed world, such as drug resistance. What then is the vision for natural product research to maintain the choices of drug discovery and pharmaceutical development for future generations?  In this discussion some facets of how natural products must be involved globally, in a sustainable manner, for improving health care will be examined within the framework of the new term “ecopharmacognosy”, which invokes sustainability as the basis for research on biologically active natural products.  Access to the biome, the acquisition, analysis and dissemination of plant knowledge, natural product structure diversification, biotechnology development, strategies for natural product drug discovery, and aspects of multitarget

  4. Natural radioactivity levels and heavy metals in chemical and organic fertilizers used in Kingdom of Saudi Arabia.

    Science.gov (United States)

    El-Taher, A; Althoyaib, S S

    2012-01-01

    The present work deals with identifying and determining the activity levels of natural occuring radionuclides, (226)Ra and (232)Th series, their decay products and (40)K, in chemical and organic fertilizers used in Kingdom of Saudi Arabia. A total of 30 samples: 20 phosphatic fertilizers (single super-phosphate SSP and triple super-phosphate,TSP) and 10 organic fertilizers (cow, sheep and chicken) collected from markets and farms. The gamma-ray spectrometer consists of NaI(Tl) detector and its electronic circuit was used for measuring γ-ray spectra. The ranges of radioactivity levels of (226)Ra, (232)Th and (40)K in chemical fertilizers are 51.5±5.2-106.3±7.5, 5.1±1.6-9.9±3.2. and 462.6±21-607.3±14Bqkg(-1), respectively. The activities of (226)Ra, (232)Th and (40)K in natural fertilizers (cow, sheep and chicken) are lower than the activities in chemical fertilizers. The obtained data are compared with available reported data from other countries in literature. The Ra(eq) in chemical fertilizer ranges from 100.37 to 161.43Bqkg(-1) and in organic fertilizer ranges from 34.07 to 102.19Bqkg(-1), which are lower than the limit of 370Bqkg(-1) adopted from NEA-OECD (1979). The average heavy metal (Pb, Cd, Ni, Co and Cr) contents of the fertilizers marketed in the Kingdom of Saudi Arabia are also determined and within the limits of those used worldwide. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Tuning the performance of a natural treatment process using metagenomics for improved trace organic chemical attenuation

    KAUST Repository

    Drewes, Jorg

    2014-02-01

    By utilizing high-throughput sequencing and metagenomics, this study revealed how the microbial community characteristics including composition, diversity, as well as functional genes in managed aquifer recharge (MAR) systems can be tuned to enhance removal of trace organic chemicals of emerging concern (CECs). Increasing the humic content of the primary substrate resulted in higher microbial diversity. Lower concentrations and a higher humic content of the primary substrate promoted the attenuation of biodegradable CECs in laboratory and field MAR systems. Metagenomic results indicated that the metabolic capabilities of xenobiotic biodegradation were significantly promoted for the microbiome under carbon-starving conditions. © IWA Publishing 2014.

  6. Respect for the environment-a chemical company's vision for a partnership with nature

    International Nuclear Information System (INIS)

    Presting D.B.

    1993-01-01

    This paper presents the environmental stewardship principles of the Du Pont Agricultural Products developed recently. The author initiates the paper with a discussion of some factors that will influence the evolution of agriculture into the next century: production and distribution of food; human population growth and areas of most rapid increase; proportion of the earth's surface that is arable; place of plant protection chemicals in production agriculture. The nine point Du Pont stewardship program includes the following areas: food and fiber safety; disease and residue level detection program; surface and ground water quality; worker safety; on-target use, resistance management, and wildlife and resource conservation; integrated ecosystem management; waste management; product quality

  7. Potential of Lactobacillus plantarum ccm 3627 and Lactobacillus brevis ccm 1815 for fermentation of cereal substrates

    Directory of Open Access Journals (Sweden)

    Kvetoslava Romanová

    2017-01-01

    Full Text Available Lactobacillus is the most representative strain in a group of lactic acid bacteria, which perform an essential role in the preservation and production of wholesome foods. Lactic acid fermentation is the oldest traditional method for preparation of fermented vegetables, meat products, dairy products and cereal foods. Cereal grains are considered to be one of the most important sources of dietary proteins, carbohydrates, vitamins, minerals and fibre for people. The main exploitation of cereals is to prepare sourdough, which is a mixture of wheat, rye or other cereal flour with water and contains yeasts and lactobacilli. The basic biochemical changes that occur in sourdough bread fermentation are acidification of the dough with organic acids produced by the lactobacilli and leavening with carbon dioxide produced by the yeast and the lactobacilli. Acidification perhaps initiate enzymatic processes of proteins and phytates degradation. Lactobacilli produce various enzymes which make flavour precursors, improve of mineral bioavailability or degrade celiac active peptides, because some species of lactobacilli produce specific peptidases during growth, which are capable to hydrolyze hardly cleavable, celiac-active proline-rich peptides. Microbial fermentation with selected strains of lactobacilli may be new alternative approach for modification of gluten by hydrolysis. In this paper are described growth characteristics and intracellular aminopeptidases activities of Lactobacillus plantarum CCM 3627 and Lactobacillus brevis CCM 1815. Work was focused on characterization of the lactobacilli for potential usage as a starter culture in further fermentation experiments.

  8. Brevetoxin exposure in sea turtles in south Texas (USA) during Karenia brevis red tide.

    Science.gov (United States)

    Walker, Jennifer Shelby; Shaver, Donna J; Stacy, Brian A; Flewelling, Leanne J; Broadwater, Margaret H; Wang, Zhihong

    2018-01-31

    Five green (Chelonia mydas) and 11 Kemp's ridley (Lepidochelys kempii) sea turtles found dead, or that died soon after stranding, on the southern Texas (USA) coast during 2 Karenia brevis blooms (October 2015, September-October 2016) were tested for exposure to brevetoxins (PbTx). Tissues (liver, kidney) and digesta (stomach and intestinal contents) were analyzed by ELISA. Three green turtles found alive during the 2015 event and 2 Kemp's ridley turtles found alive during the 2016 event exhibited signs of PbTx exposure, including lethargy and/or convulsions of the head and neck. PbTx were detected in 1 or more tissues or digesta in all 16 stranded turtles. Detected PbTx concentrations ranged from 2 to >2000 ng g-1. Necropsy examination and results of PbTx analysis indicated that 10 of the Kemp's ridleys and 2 of the green turtles died from brevetoxicosis via ingestion. This is the first documentation of sea turtle mortality in Texas attributed to brevetoxicosis.

  9. Lateral line analogue aids vision in successful predator evasion for the brief squid, Lolliguncula brevis.

    Science.gov (United States)

    York, Carly A; Bartol, Ian K

    2014-07-15

    Cephalopods have visual and mechanoreception systems that may be employed to sense and respond to an approaching predator. While vision presumably plays the dominant role, the importance of the lateral line analogue for predator evasion has not been examined in cephalopods. To test the respective roles of vision and the lateral line analogue, brief squid, Lolliguncula brevis, were observed in the presence of summer flounder, Paralichthys dentatus, under light and dark conditions with their lateral line analogue intact and ablated. Hair cell ablation was achieved through a pharmacological technique used for the first time on a cephalopod. The proportion of predator-prey interactions survived was significantly higher in the light non-ablated and light ablated groups compared with the dark ablated group. The mean number of interactions survived varied across treatment groups with the light non-ablated group having significantly more success than the light ablated, dark non-ablated and dark ablated groups. These findings demonstrate that although vision is the primary sense, the lateral line analogue also contributes to predator evasion in squid. © 2014. Published by The Company of Biologists Ltd.

  10. Clinical Significance of Presence of Extensor Indicis Brevis Manus – A Case Report

    Directory of Open Access Journals (Sweden)

    N Esakkiammal

    2017-11-01

    Full Text Available Anatomical variations of additional muscles and tendons are commonly encountered in extensor aspect of forearm and hand during surgeries and dissections. There are reports on different kinds of variations like, extra tendons, additional bellies, and abnormal attachments of the muscle. Surgeons should have the knowledge about these variations for muscle or tendon grafting and also to plan surgeries. While dissecting the extensor compartment forearm and dorsum of hand of an elderly female cadaver, an anomalous muscle belly was noticed on dorsum of hand bilaterally alongwith the main tendon of extensor indicis muscle. This additional belly of extensor indicis muscle was called Extensor Indicis Brevis Manus (EIBM. This muscle originated from the dorsal carpal ligament and joined the main tendon of extensor indicis muscle in both the hands. Awareness of existence of this kind of variation is important for clinicians and surgeons for a correct diagnosis and eventual surgery in patients presenting with a cyst on the dorsum of hand, to avoid accidental mishaps.

  11. Heterogeneity between and within Strains of Lactobacillus brevis Exposed to Beer Compounds.

    Science.gov (United States)

    Zhao, Yu; Knøchel, Susanne; Siegumfeldt, Henrik

    2017-01-01

    This study attempted to investigate the physiological response of six Lactobacillus brevis strains to hop stress, with and without the addition of Mn 2+ or ethanol. Based on the use of different fluorescent probes, cell viability and intracellular pH (pHi) were assessed by fluorescence microscopy combined with flow cytometry, at the single cell level. The combined approach was faster than the traditional colony based method, but also provided additional information about population heterogeneity with regard to membrane damage and cell size reduction, when exposed to hop compounds. Different physiological subpopulations were detected under hop stress in both hop tolerant and sensitive strains. A large proportion of cells were killed in all the tested strains, but a small subpopulation from the hop tolerant strains eventually recovered as revealed by pHi measurements. Furthermore, a short term protection against hop compounds was obtained for both hop tolerant and sensitive strains, by addition of high concentration of Mn 2+ . Addition of ethanol in combination with hop compounds caused an additional short term increase in damaged subpopulation, but the subsequent growth suggested that the presence of ethanol provides a slight cross resistance toward hop compounds.

  12. Prevalence of Demodex folliculorum and Demodex brevis in childhood malnutrition and malignancy.

    Science.gov (United States)

    Kaya, Sadik; Selimoglu, Mukadder Ayse; Kaya, Ozlem Aycan; Ozgen, Unsal

    2013-02-01

    Hair follicle mites, Demodex folliculorum and Demodex brevis, are known to accompany immune-deficiency states, however no study so far has investigated their presence in malnutrition. In this study we aimed to determine the prevalence of those mites in childhood malnutrition, malignancy and risk factors. One hundred children with malnutrition, 31 children with malignancy and 63 children without any chronic disease and infection were included in this study. History, physical examination, anthropometric measurements and routine laboratory findings were recorded. Demodex spp. were investigated by standard superficial skin biopsies. Demodex was found in 25 patients (25%), 10 patients (32.3%), and one patient (1.6%) among malnutrition, malignancy, and control groups, respectively (P = 0.001). By using multilogistic regression binary method, it was found that malnutrition, malignancy and low socioeconomic level increased the risk 17.37 times (P = 0.006), 27.29 times (P = 0.002), and 2.3 times (P = 0.037), respectively. Of 22 children who were evaluated after 6 months, 13 (59.1%) were negative for Demodex. In 11 (84.6%) of those 13, nutritional status was improved. Demodex was detected in approximately in one-quarter and one-third of children with malnutrition and malignancy, respectively. Eliminating the cause of immunosuppression, such as poor nutritional status, seems also to be an effective method for eliminating Demodex. © 2012 The Authors. Pediatrics International © 2012 Japan Pediatric Society.

  13. Gamma-aminobutyric acid fermentation with date residue by a lactic acid bacterium, Lactobacillus brevis.

    Science.gov (United States)

    Hasegawa, Momoko; Yamane, Daisuke; Funato, Kouichi; Yoshida, Atsushi; Sambongi, Yoshihiro

    2018-03-01

    Dates are commercially consumed as semi-dried fruit or processed into juice and puree for further food production. However, the date residue after juice and puree production is not used, although it appears to be nutrient enriched. Here, date residue was fermented by a lactic acid bacterium, Lactobacillus brevis, which has been generally recognized as safe. Through degradation of sodium glutamate added to the residue during the fermentation, γ-aminobutyric acid (GABA), which reduces neuronal excitability, was produced at the conversion rate of 80-90% from glutamate. In order to achieve this GABA production level, pretreatment of the date residue with carbohydrate-degrading enzymes, i.e., cellulase and pectinase, was necessary. All ingredients used for this GABA fermentation were known as being edible. These results provide us with a solution for the increasing commercial demand for GABA in food industry with the use of date residue that has been often discarded. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  14. Crystallization and preliminary crystallographic analysis of a flavoprotein NADH oxidase from Lactobacillus brevis

    International Nuclear Information System (INIS)

    Kuzu, Mutlu; Niefind, Karsten; Hummel, Werner; Schomburg, Dietmar

    2005-01-01

    The water-forming flavoenzyme NADH oxidase was crystallized successfully for the first time. The crystals diffract X-rays to at least 4.0 Å resolution. NADH oxidase (NOX) from Lactobacillus brevis is a homotetrameric flavoenzyme composed of 450 amino acids per subunit. The molecular weight of each monomer is 48.8 kDa. The enzyme catalyzes the oxidation of two equivalents of NADH and reduces one equivalent of oxygen to yield two equivalents of water, without releasing hydrogen peroxide after the reduction of the first equivalent of NADH. Crystals of this protein were grown in the presence of 34% polyethylene glycol monomethyl ether 2000, 0.1 M sodium acetate and 0.2 M ammonium sulfate at pH 5.4. They belong to the tetragonal space group P4 3 2 1 2, with unit-cell parameters a = 74.8, b = 95.7, c = 116.9 Å, α = γ = 90, β = 103.8°. The current diffraction limit is 4.0 Å. The self-rotation function of the native data set is consistent with a NOX tetramer in the asymmetric unit

  15. Causal knowledge extraction by natural language processing in material science: a case study in chemical vapor deposition

    Directory of Open Access Journals (Sweden)

    Yuya Kajikawa

    2006-11-01

    Full Text Available Scientific publications written in natural language still play a central role as our knowledge source. However, due to the flood of publications, the literature survey process has become a highly time-consuming and tangled process, especially for novices of the discipline. Therefore, tools supporting the literature-survey process may help the individual scientist to explore new useful domains. Natural language processing (NLP is expected as one of the promising techniques to retrieve, abstract, and extract knowledge. In this contribution, NLP is firstly applied to the literature of chemical vapor deposition (CVD, which is a sub-discipline of materials science and is a complex and interdisciplinary field of research involving chemists, physicists, engineers, and materials scientists. Causal knowledge extraction from the literature is demonstrated using NLP.

  16. Significance of the molecular diffusion for chemical and isotopic separation during the formation and degradation of natural gas reservoirs

    International Nuclear Information System (INIS)

    Hermichen, W.D.; Schuetze, H.

    1987-01-01

    Investigations at natural gas fields as well as modelling experiments have pointed out that changes of the chemical and isotopic composition occur in the course of migration, accumulation and dispersion of natural gas. Dissolution and sorption processes as well as in particular the diffusion process are considered to be the elementary separation processes. The influences on dissolved and freely flowing gases and on stationary gas accumulation are described by differential equations. The simulation of the following phenomena is shown: (1) immigration of gas into the pore space which is hydrodynamically passive, (2) diffusive migration of gas into the environment of the accumulation, and (3) diffusive 'decompression' into the roof and the floor of a gas bed and a gas containing subsoil water stratum, respectively. (author)

  17. Application of the natural cellulosic supports modified chemically for the treatment of the industrial effluents

    International Nuclear Information System (INIS)

    Kassale, A.; Elbariji, S.; Lacherai, A.; Elamine, M.; Kabli, H.; Albourine, A.

    2009-01-01

    The process of purification and discoloration of industrial waters (and particularly effluents of the textile industry) can meet major difficulties: certain dyes agents get through the devices of purge without being to stop. the cost of equipment and products of purification is prohibitive. Finally, in many cases, the discoloration can be only partial because waters to be treated containing mixtures of dyes of different nature, the material of purification can be effective only screw/screw of some of them. (Author)

  18. 1,5-Dimethylhexylamine (octodrine) in sports and weight loss supplements: Natural constituent or synthetic chemical?

    Science.gov (United States)

    Wang, Mei; Haider, Saqlain; Chittiboyina, Amar G; Parcher, Jon F; Khan, Ikhlas A

    2018-04-15

    In the past years, there has been a mounting trend toward the addition of sympathomimetic stimulants in sports and weight loss supplements sold in the US and claimed to be from natural constituents. The latest among those pharmaceutical stimulants is 1,5-dimethylhexylamine (1,5-DMHA or octodrine), an ingredient in newly introduced sports and weight loss supplements with its 'natural' origin being cited from Aconitum or Kigelia plants. In order to validate the natural existence of 1,5-DMHA, two GC/MS methods were developed. One method involved using thick film megabore capillary columns to analyze the underivatized 1,5-DMHA. The second method was to determine enantiomeric distribution of 1,5-DMHA. Fifteen Aconitum or Kigelia plant samples originating from various locations were analyzed, and none of them contained 1,5-DMHA within the limit of detection (25 ng/mL) of the method. In contrast, although 1,5-DMHA was listed on the labels or website for all the 13 dietary supplements, only four products were found to contain this compound, with the highest quantity being reported as 112 mg per serving size. This is equivalent to more than three times the highest pharmaceutical dose established in Europe. The enantiomeric ratios of 1,5-DMHA in these products were determined to be between 0.9-1.0 (expressed as peak area ratio of one enantiomer over another), suggesting racemic nature. Interestingly, two byproducts from 1,5-DMHA synthesis were identified in commercial supplements containing 1,5-DMHA, indicating that 1,5-DMHA indeed originated from a poor quality source. Overall, the significant amount of 1,5-DMHA observed in the supplements, the enantiomeric distribution and the presence of the synthetic byproducts all suggested the synthetic origin of 1,5-DMHA in the commercial products. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. In vitro activity of natural and chemical products on sporulation of Eimeria species oocysts of chickens.

    Science.gov (United States)

    Gadelhaq, Sahar M; Arafa, Waleed M; Abolhadid, Shawky M

    2018-02-15

    This study was designed to investigate the ability of two herbal extracts and different chemical substances to inhibit or disrupt sporulation of Eimeria species oocysts of the chickens. The two herbal extracts were Allium sativum (garlic) and Moringa olifiera while the chemical substances included commercial disinfectants and diclazuril. Field isolates of Eimeria oocysts were propagated in chickens to obtain a continuous source of oocysts. The collected unsporulated oocysts (10 5 oocysts/5 ml) were dispensed into 5 cm Petri dish. Three replicates were used for each treatment. The treated oocysts were incubated for 48 h at 25-29 °C and 80% relative humidity. The results showed that herbal extracts, the commercial recommended dose of Dettol, TH4, Phenol, Virkon ® S, and Diclazuril 20% have no effect on the sporulation. While Sodium hypochlorite showed a significant degree of sporulation inhibition reached to 49.67%. Moreover, 70% ethanol, and 10% formalin showed 100% sporulation inhibition. It was concluded that 70% ethanol and 10% formalin are the most effective methods to inhibit Eimeria species sporulation. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Kinetics of Natural Attenuation: Review of the Critical Chemical Conditions and Measurements at Bore Scale

    Directory of Open Access Journals (Sweden)

    O. Atteia

    2002-01-01

    Full Text Available This paper describes the chemical conditions that should favour the biodegradation of organic pollutants. Thermodynamic considerations help to define the reaction that can occur under defined chemical conditions. The BTEX (benzene, toluene, ethylbenzene, and xylene degradation is focused on benzene, as it is the most toxic oil component and also because it has the slowest degradation rate under most field conditions. Several studies on benzene degradation allow the understanding of the basic degradation mechanisms and their importance in field conditions. The use of models is needed to interpret field data when transport, retardation, and degradation occur. A detailed comparison of two existing models shows that the limits imposed by oxygen transport must be simulated precisely to reach correct plumes shapes and dimensions, and that first-order kinetic approaches may be misleading. This analysis led us to develop a technique to measure directly biodegradation in the field. The technique to recirculate water at the borehole scale and the CO2 analysis are depicted. First results of biodegradation show that this technique is able to easily detect the degradation of 1 mg/l of hydrocarbons and that, in oxic media, a fast degradation rate of mixed fuel is observed.

  1. studies on the fixation of chemical and radioactive contaminants by natural and artificial compounds

    International Nuclear Information System (INIS)

    Mourad, G.A.M.

    2006-01-01

    the main objective of the work presented in this is to study the adsorption of U(VI), Cr(VI) and Gd (lll) from aqueous medium using modified sorel's cement as artificial adsorbents. the thesis is classified into three chapters; namely ,introduction ,experimental and results and discussion. the first chapter, i ntroduction , includes chemical and radioactive contaminant, some aspects of the properties and aqueous chemistry of uranium, chromium and gadolinium . the separation of different pollutant and their methods of separation based on the types of adsorbents, and the theoretical background of adsorption isotherms, kinetics and ion diffusion as well as literature survey which is related to the present work are given.the second chapter, e xperimental , contains the different materials employed, their chemical purity, and a detailed description for instruments used are given.the third chapter. r esults and discussion i ncludes the experimental results obtained and their interpretation .this chapter is classified into three main parts; namely, characterization, equilibrium and kinetic investigations

  2. Natural Chemical Composition of Commercial Fish Species: Characterisation of Pangasius, Wild and Farmed Turbot and Barramundi

    Science.gov (United States)

    Manthey-Karl, Monika; Lehmann, Ines; Ostermeyer, Ute; Schröder, Ute

    2016-01-01

    To comply with the relevant legal requirements and correct labelling, it is necessary for business operators and inspection authorities to know the natural characteristics of the raw material. This study gives a comprehensive overview of muscle flesh composition of farmed and wild Atlantic turbot (Scophthalmus maximus) and barramundi (Lates calcarifer) and of farmed pangasius (Pangasianodon hypophthalmus). The proximate composition, di- and triphosphates and citric acid values are presented in order to evaluate possible indicators for a hidden treatment during processing to fillets. All moisture contents were ≤80%. Even for pangasius, protein values for deep skinned fillets of ≥18% were determined. Only small quantities of naturally occurring citric acid (up to 0.03 g·kg−1) were detectable. The lipid content was the most varying main component within the different species, ranging between 1.2% to 2.0% and 0.3% to 3.0% for farmed turbot and barramundi, respectively. Pangasius flesh had a mean lipid content of 7.8%. Trimming and separation of the red layer reduced the lipid content of the commercially sold white-flesh fillets to 2.7% to 3.5%. Fatty acids profiles, free amino acids, and minerals were analysed to show the nutritional quality of the aquaculture fish species and compared to wild turbot and barramundi. Despite some natural variation, these components can be considered as comparable. PMID:28231154

  3. Natural Chemical Composition of Commercial Fish Species: Characterisation of Pangasius, Wild and Farmed Turbot and Barramundi

    Directory of Open Access Journals (Sweden)

    Monika Manthey-Karl

    2016-08-01

    Full Text Available To comply with the relevant legal requirements and correct labelling, it is necessary for business operators and inspection authorities to know the natural characteristics of the raw material. This study gives a comprehensive overview of muscle flesh composition of farmed and wild Atlantic turbot (Scophthalmus maximus and barramundi (Lates calcarifer and of farmed pangasius (Pangasianodon hypophthalmus. The proximate composition, di- and triphosphates and citric acid values are presented in order to evaluate possible indicators for a hidden treatment during processing to fillets. All moisture contents were ≤80%. Even for pangasius, protein values for deep skinned fillets of ≥18% were determined. Only small quantities of naturally occurring citric acid (up to 0.03 g·kg−1 were detectable. The lipid content was the most varying main component within the different species, ranging between 1.2% to 2.0% and 0.3% to 3.0% for farmed turbot and barramundi, respectively. Pangasius flesh had a mean lipid content of 7.8%. Trimming and separation of the red layer reduced the lipid content of the commercially sold white-flesh fillets to 2.7% to 3.5%. Fatty acids profiles, free amino acids, and minerals were analysed to show the nutritional quality of the aquaculture fish species and compared to wild turbot and barramundi. Despite some natural variation, these components can be considered as comparable.

  4. Natural gas as raw material for clean fuels and chemicals in the next decades

    International Nuclear Information System (INIS)

    Colitti, M.

    1998-01-01

    Modern industry originates in a change of feedstock, the result of a never-ending quest for a better, cheaper raw material. In the origin, there was coal, a source of both energy and industrial feedstock, the so-called synthesis gas. Then, coal was replaced by liquid hydrocarbons, coming from a refinery or from wells of crude oil and gas. The passage from solid to liquids was part and parcel of a structural change which has produced an extraordinary acceleration of economic growth. We might hope that the same will happen when natural gas will comes in to displace the liquids. New feedstocks do not come in without a fight. It is not only a matter of price, but also of technology, and of the natural tendency of industries to protect their own investments in plants which are all of a sudden made to look old. Rather than repeat for the 'nth' time the list of technologies which can turn natural gas into a basic feedstock for oil and petrochemical industries, the author discusses how will companies decide upon this matter

  5. Effects of chemical elements in the trophic levels of natural salt marshes.

    Science.gov (United States)

    Kamiński, Piotr; Barczak, Tadeusz; Bennewicz, Janina; Jerzak, Leszek; Bogdzińska, Maria; Aleksandrowicz, Oleg; Koim-Puchowska, Beata; Szady-Grad, Małgorzata; Klawe, Jacek J; Woźniak, Alina

    2016-06-01

    The relationships between the bioaccumulation of Na, K, Ca, Mg, Fe, Zn, Cu, Mn, Co, Cd, and Pb, acidity (pH), salinity (Ec), and organic matter content within trophic levels (water-soil-plants-invertebrates) were studied in saline environments in Poland. Environments included sodium manufactures, wastes utilization areas, dumping grounds, and agriculture cultivation, where disturbed Ca, Mg, and Fe exist and the impact of Cd and Pb is high. We found Zn, Cu, Mn, Co, and Cd accumulation in the leaves of plants and in invertebrates. Our aim was to determine the selectivity exhibited by soil for nutrients and heavy metals and to estimate whether it is important in elucidating how these metals are available for plant/animal uptake in addition to their mobility and stability within soils. We examined four ecological plant groups: trees, shrubs, minor green plants, and water macrophytes. Among invertebrates, we sampled breastplates Malacostraca, small arachnids Arachnida, diplopods Diplopoda, small insects Insecta, and snails Gastropoda. A higher level of chemical elements was found in saline polluted areas (sodium manufactures and anthropogenic sites). Soil acidity and salinity determined the bioaccumulation of free radicals in the trophic levels measured. A pH decrease caused Zn and Cd to increase in sodium manufactures and an increase in Ca, Zn, Cu, Cd, and Pb in the anthropogenic sites. pH increase also caused Na, Mg, and Fe to increase in sodium manufactures and an increase in Na, Fe, Mn, and Co in the anthropogenic sites. There was a significant correlation between these chemical elements and Ec in soils. We found significant relationships between pH and Ec, which were positive in saline areas of sodium manufactures and negative in the anthropogenic and control sites. These dependencies testify that the measurement of the selectivity of cations and their fluctuation in soils provide essential information on the affinity and binding strength in these environments. The

  6. Chemical conversion of natural gas. Final report; Kjemisk konvertering av naturgass. Sluttrapport

    Energy Technology Data Exchange (ETDEWEB)

    Simonsen, Haavard

    2000-07-01

    This report presents examples of gas research of a high international class. This research has strengthened the technological position of Norwegian industry in the field of gas utilization, which will be of great importance for Norwegian industry, nationally and internationally. The competence of the research and development institutions has been further developed within the subjects of catalysis, reactor technology and chemical engineering. These subjects are of central importance irrespective of whether or not the gas is to be utilized with or without CO{sub 2} deposition, for synthetic diesel, for methanol, for olefins, for proteins, for hydrogen or other purposes. The main purpose of the programme discussed was to educate PhDs and to develop skill of strategic importance for Norwegian industry. There are sections on synthesis gas, direct conversion, methanol to olefins, fluidized bed reactors and system technology.

  7. Natural Gamma Emitters after a Selective Chemical Separation of a TENORM residue: Preliminary Results

    International Nuclear Information System (INIS)

    Alves de Freitas, Antonio; Abrao, Alcidio; Godoy dos Santos, Adir Janete; Pecequilo, Brigitte Roxana Soreanu

    2008-01-01

    An analytical procedure was established in order to obtain selective fractions containing radium isotopes ( 228 Ra), thorium ( 232 Th), and rare earths from RETOTER (REsiduo de TOrio e TErras Raras), a solid residue rich in rare earth elements, thorium isotopes and small amount of natural uranium generated from the operation of a thorium pilot plant for purification and production of pure thorium nitrate at IPEN -CNEN/SP. The paper presents preliminary results of 228 Ra, 226 Ra, 238 U, 210 Pb, and 40 K concentrations in the selective fractions and total residue determined by high-resolution gamma spectroscopy, considering radioactive equilibrium of the samples

  8. Liquid Membranes as a Tool for Chemical Speciation of Metals in Natural Waters: Organic and Inorganic Complexes of Nickel.

    Science.gov (United States)

    Vergel, Cristina; Mendiguchía, Carolina; Moreno, Carlos

    2018-04-15

    The different species of nickel present in natural waters exhibit different transport behaviour through bulk liquid membranes (BLMs). This fact has been used to design and optimise a separation/pre-concentration system applicable to separate labile and non-labile nickel fractions. A hydrazone derivative-1,2-cyclohexanedione bis-benzoyl-hydrazone (1,2-CHBBH) dissolved in toluene/dimethyl formamide (2% DMF)-was used as a chemical carrier of nickel species, from an aqueous source solution (sample) to a receiving acidic solution. Both chemical and hydrodynamic conditions controlling the transport system were studied and optimised. Under optimum conditions, variations in the transport of nickel ions as a function of organic (humic acids) and inorganic (chloride ions) ligands were studied. Relationships between the permeability coefficient ( P ) or recovery efficiency (%R) and the concentrations of ligands and nickel species were analysed using Winhumic V software. A negative correlation between P and the concentration of organic nickel complexes was found, suggesting that only labile nickel species are transported through the liquid membrane, with non-labile complexes remaining in the water sample; allowing for their separation and subsequent quantification in natural waters.

  9. Evaluation of some microbial agents, natural and chemical compounds for controlling tomato leaf miner, Tuta absoluta (Meyrick (Lepidoptera: Gelechiidae

    Directory of Open Access Journals (Sweden)

    Abd El-Ghany Nesreen M.

    2016-12-01

    Full Text Available Solanaceous plants have a great economic impact in Egypt. These groups of plants include potatoes, tomatoes and eggplants. The new invasive pest of tomatoes, Tuta absoluta (Meyrick causes the greatest crop losses which can range from 60 to 100%. After its detection in Egypt during the last half of 2009, it spread quickly to all provinces in the country. We aiming to propose a sustainable control program for this devastating pest. In this research we tested three groups of control agents. The first was microbial and natural, the second - plant extracts and the third - chemical insecticides. Our results showed that the impact of T. absoluta can be greatly reduced by the use of sustainable control measures represented by different insecticide groups. Bioassay experiments showed that this devastating pest can be controlled with some compounds that give high mortality rates. Of these compounds, spinosad and Beauveria bassiana, microbial control agents, followed by azadirachtin, gave the best results in controlling T. absoluta. Of the chemical insecticides, lambda-cyhalotrin was the most effective, followed by lufenuron and profenofos. In conclusion we encourage farmers to use microbial and natural control measures in combating the tomato leafminer, T. absoluta, in Integrated Pest Mangement (IPM programs.

  10. Liquid Membranes as a Tool for Chemical Speciation of Metals in Natural Waters: Organic and Inorganic Complexes of Nickel

    Directory of Open Access Journals (Sweden)

    Cristina Vergel

    2018-04-01

    Full Text Available The different species of nickel present in natural waters exhibit different transport behaviour through bulk liquid membranes (BLMs. This fact has been used to design and optimise a separation/pre-concentration system applicable to separate labile and non-labile nickel fractions. A hydrazone derivative—1,2-cyclohexanedione bis-benzoyl-hydrazone (1,2-CHBBH dissolved in toluene/dimethyl formamide (2% DMF—was used as a chemical carrier of nickel species, from an aqueous source solution (sample to a receiving acidic solution. Both chemical and hydrodynamic conditions controlling the transport system were studied and optimised. Under optimum conditions, variations in the transport of nickel ions as a function of organic (humic acids and inorganic (chloride ions ligands were studied. Relationships between the permeability coefficient (P or recovery efficiency (%R and the concentrations of ligands and nickel species were analysed using Winhumic V software. A negative correlation between P and the concentration of organic nickel complexes was found, suggesting that only labile nickel species are transported through the liquid membrane, with non-labile complexes remaining in the water sample; allowing for their separation and subsequent quantification in natural waters.

  11. Expanding the chemical space for natural products by Aspergillus-Streptomyces co-cultivation and biotransformation

    Science.gov (United States)

    Wu, Changsheng; Zacchetti, Boris; Ram, Arthur F.J.; van Wezel, Gilles P.; Claessen, Dennis; Hae Choi, Young

    2015-01-01

    Actinomycetes and filamentous fungi produce a wide range of bioactive compounds, with applications as antimicrobials, anticancer agents or agrochemicals. Their genomes contain a far larger number of gene clusters for natural products than originally anticipated, and novel approaches are required to exploit this potential reservoir of new drugs. Here, we show that co-cultivation of the filamentous model microbes Streptomyces coelicolor and Aspergillus niger has a major impact on their secondary metabolism. NMR-based metabolomics combined with multivariate data analysis revealed several compounds that correlated specifically to co-cultures, including the cyclic dipeptide cyclo(Phe-Phe) and 2-hydroxyphenylacetic acid, both of which were produced by A. niger in response to S. coelicolor. Furthermore, biotransformation studies with o-coumaric acid and caffeic acid resulted in the production of the novel compounds (E)-2-(3-hydroxyprop-1-en-1-yl)-phenol and (2E,4E)-3-(2-carboxy-1-hydroxyethyl)-2,4-hexadienedioxic acid, respectively. This highlights the utility of microbial co-cultivation combined with NMR-based metabolomics as an efficient pipeline for the discovery of novel natural products. PMID:26040782

  12. IMPROVING POSTHARVEST VASE-LIFE AND QUALITY OF CUT GERBERA FLOWERS USING NATURAL AND CHEMICAL PRESERVATIVES

    Directory of Open Access Journals (Sweden)

    Mehrdad Jafarpour

    2015-06-01

    Full Text Available Gerbera is one of ten popular cut flowers in the world which occupies the forth place according to the global trends in floriculture. Hence, this study aimed to investigate the effects of chemical, hormonal and essential oil substances in preservative solutions to improve its postharvest qualitative characteristics. Two pulse treatments including distilled water (pulse1 and 4% CaCl2 + 3% sucrose (pulse2 for 24 hour were applied before long-time treatments. Long-time treatments were comprised of (1 Hormonal treatments: 0, 25, 30 mg*l-1 Gibberellic acid, 0, 150, 250 mg*l-1 Benzyl adenine and 0, 100, 200 mg*l-1 5-Sulfosalicylic acid (2 Chemical treatments: 0, 0.4, 0.8 mM Silver thiosulphate, 0, 5, 10 mg*l-1 Nano-silver particles, 0, 4, 6 mM Aminooxy acetic acid and 0, 200 and 400 mg*l-1 8-hydroxyquinoline sulphate (3 Essential oils: Thymus essential oil and Stevia essential oils (0, 0.1 and 0.2 mg*l-1. Data were subjected to analysis of variance based on the factorial experiment model in the layout completely randomized design. Mean comparison was performed using the Duncan’s multiple range test. Parameters of fresh weight, stem bending, capitulum diameter, carotenoid pigments of petal and vase-life longevity were evaluated during 12 days. The highest fresh weight was obtained when cut flowers were held in a solution containing pulse1 + 250 mg*l-1 BA. Among all treatments, 8-HQS treatment showed the best effects on preventing stem bending, increasing capitulum diameter and also on prolonging of vase-life, but nonetheless, the effects of pulse treatments and 8-HQS concentrations were insignificant. To conclude, 200 mg*l-1 8-HQS without pulse treatment has the potential to be used as a commercial preservative solution to improve the keeping quality and vase-life of this important cut flower.

  13. Electron nature of chemically active state of spiropyran with nitro group. Dependence of efficiency of radiation colouring of spiropyrans on their structure

    International Nuclear Information System (INIS)

    Kholmanskij, A.S.; Zubkov, A.V.; Dyumaev, K.M.

    1980-01-01

    Using the theory of solvatochromy it is shown that chemically active state of spiropyran with nitro group is its highly polar electron-excitated state. On the basis of the image on the electron nature of chemically active state of spiropyran the dependence of the values of radiation yield of the coloured forms of spiropyrans upon their structure is explained

  14. The development of portable equipment to study physical and chemical phases in natural waters

    International Nuclear Information System (INIS)

    Breward, N.; Peachey, D.

    1988-08-01

    A direct and relatively non-invasive method of measuring the speciation of dissolved metals in groundwaters has been developed. The equipment relies on a series of columns containing DAEA cellulose, cation exchange resin and anion exchange resin to extract sequentially and respectively colloids, cationic and anionic species. Organic colloids are eluted from the DAEA cellulose with dilute caustic soda while the inorganic colloids (Fe/Al oxyhydroxide phase) are stripped with dilute mineral acid. A further advantage of this scheme is the ability to concentrate the phases by at least a factor of ten. Applications to the groundwaters of the natural analogue sites currently under study by BGS will offer a means of validating thermodynamic databases used in modelling speciation of radionuclides such as uranium and thorium. (author)

  15. Experimental and quantum chemical studies on poriferasterol - A natural phytosterol isolated from Cassia sophera Linn. (Caesalpiniaceae)

    Science.gov (United States)

    Brahmachari, Goutam; Mondal, Avijit; Nayek, Nayana; Kumar, Abhishek; Srivastava, Ambrish Kumar; Misra, Neeraj

    2017-09-01

    Poriferasterol, a biologically relevant phytosterol, has been isolated and identified first-time from Cassia sophera Linn. (family: Caesalpiniaceae) based on detailed spectral studies. Exhaustive theoretical studies on the molecular structure, vibrational spectra, HOMO, LUMO, MESP surfaces and reactivity descriptor of this plant-derived natural molecule have been performed. The experimentally observed FT-IR spectrum of the title compound has been compared with spectral data obtained by DFT-B3LYP/6-311 + G (d,p) method. The UV-visible spectrum of the title compound has also been recorded and the electronic properties, such as frontier orbitals and band gap energy are measured by TD-DFT approach. The 1H and 13C NMR spectrum has been calculated by using the gauge independent atomic orbital method and compared with the observed data.

  16. Redox oscillation impact on natural and engineered biogeochemical systems: chemical resilience and implications for contaminant mobility

    Energy Technology Data Exchange (ETDEWEB)

    Charlet, Laurent [ISTerre, University of Grenoble, B.P. 53X, 38041 Grenoble (France); Institut Universitaire de France, Paris (France); Markelova, Ekaterina [ISTerre, University of Grenoble, B.P. 53X, 38041 Grenoble (France); Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, ON N2L3G1 4 (Canada); Parsons, Chris; Couture, Raoul-Marie [Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, ON N2L3G1 4 (Canada); Made, Benoit [Andra / DRD-TR, Direction Recherche et Developpement, 1-7 rue Jean Monnet, 92298 Chatenay-Malabry cedex (France)

    2013-07-01

    Many geochemical systems fluctuate regularly from oxic to anoxic conditions (flooded soils and nuclear waste surface repositories, for instance). In these conditions many inorganic contaminants including Sb, Se, Cr, As, and U are highly sensitive to changes in redox conditions. These oscillations may result in changes to their speciation, toxicity, and mobility. We demonstrate through the combination of redox-stat batch-reactor experiments that periodic and cumulative changes to matrix mineralogy, contaminant speciation, and mineral surface properties occur following periodic cycles of reduction and oxidation. These changes result in both short-term (intra-cycle) and long-term (inter-cycle) changes to K{sub d} values for a range of redox sensitive contaminants. These results demonstrate that naturally occurring redox oscillations may result in long-term immobilization of contaminants in the solid phase in addition to short-term variations in mobility. (authors)

  17. Hydroxyapatite-based porous aggregates: physico-chemical nature, structure, texture and architecture.

    Science.gov (United States)

    Fabbri, M; Celotti, G C; Ravaglioli, A

    1995-02-01

    At the request of medical teams from the maxillofacial sector, a highly porous ceramic support based on hydroxyapatite of around 70-80% porosity was produced with a pore size distribution similar to bone texture ( 150 microns, approximately 86 vol%). The ceramic substrates were conceived not only as a fillers for bone cavities, but also for use as drug dispensers and as supports to host cells to produce particular therapeutic agents. A method is suggested to obtain a substrate of high porosity, exploiting the impregnation of spongy substrate with hydroxyapatite ceramic particles. X-ray and scanning electron microscopy analyses were carried out to evaluate the nature of the new ceramic support in comparison with the most common commercial product; pore size distribution and porosity were controlled to known hydroxyapatite ceramic architecture for the different possible uses.

  18. Chemical and isotopic composition of natural waters in the Jizuki-yama landslide area, Nagano Prefecture

    Energy Technology Data Exchange (ETDEWEB)

    Yoshioka, Ryuma; Mashima, Kiyotaka; Koizumi, Naoji

    1988-10-01

    A large-scale landslide took place at a southeastern slope of Mt. Jizuki, Nagano Prefecture, on July 26, 1985. It has been said that landslide is closely related to the hydrological and hydrogeochemical nature of groundwater involved. To investigate the weathering mechanism and the origin of groundwater, we collected and analyzed water samples from the large-scale landslide area. The following facts can be pointed out: (1) weather-rock interaction is remarkably active in the landslide area, (2) most of the waters from the landslide area are in equilibrium with Na-montmorillonite (3) immediately after the landslide occurred bicarbonate and sodium ions are dominant, but sulfate and sodium ions become dominant with time, and (4) groundwater passing through horizontally drilled holes dose not effectively drain off to stabilize a slope in the landslide area. And our hypothesis on the mechanism for the formation of sodium sulfate type water is also presented.

  19. Exposure pathways and health effects associated with chemical and radiological toxicity of natural uranium: a review.

    Science.gov (United States)

    Brugge, Doug; de Lemos, Jamie L; Oldmixon, Beth

    2005-01-01

    Natural uranium exposure derives from the mining, milling, and processing of uranium ore, as well as from ingestion of groundwater that is naturally contaminated with uranium. Ingestion and inhalation are the primary routes of entry into the body. Absorption of uranium from the lungs or digestive track is typically low but can vary depending on compound specific solubility. From the blood, two-thirds of the uranium is excreted in urine over the first 24 hours and up to 80% to 90% of uranium deposited in the bone leaves the body within 1.5 years. The primary health outcomes of concern documented with respect to uranium are renal, developmental, reproductive, diminished bone growth, and DNA damage. The reported health effects derive from experimental animal studies and human epidemiology. The Lowest Observed Adverse Effect Level (LOAEL) derived from animal studies is 50 microg/m3 for inhalation and 60 ug/kg body weight/day for ingestion. The current respiratory standard of the Occupational Safety and Health Administration (OSHA), 50 microg/m3, affords no margin of safety. Considering the safety factors for species and individual variation, the ingestion LOAEL corresponds to the daily consumption set by the World Health Organization Drinking Water Standard at 2 microg/L. Based on economic considerations, the United States Environmental Protection Agency maximum contaminant level is 30 microg/L. Further research is needed, with particular attention on the impact of uranium on indigenous populations, on routes of exposure in communities near uranium sites, on the combined exposures present at many uranium sites, on human developmental defects, and on health effects at or below established exposure standards.

  20. The nature of outsourced preclinical research--the example of chemical synthesis.

    Science.gov (United States)

    Festel, Gunter W

    2013-09-01

    The possibility to buy standardized external services or even new and innovative methods within drug discovery has increased dramatically during the last decades. Service providers are able to provide timely and efficient solutions to any given problem within preclinical research. The outsourcing behavior depends on the specific company type. Generally, the outsourcing level of emerging pharmaceutical and biotechnology companies is much higher than established companies due to low or missing internal resources. Whereas the "make-or-buy" decisions of large and fully integrated pharmaceutical companies are mainly competency driven, those of mid-size and small pharmaceutical, as well as biotech companies show a specific combination of cost/capacity and competency. The three different cooperation models "price competition", "project selection," and "strategic partnership" were identified. For all types of companies, the cooperation model of "strategic partnership" offers access to high-level expertise while reducing fixed costs and complexity. This was shown using chemical synthesis as an example but is also true for other areas of preclinical research.

  1. Hydraulic Behavior and Chemical Characterization of Lapilli as Material for Natural Filtering of Slurry

    Directory of Open Access Journals (Sweden)

    Nereida Falcón-Cardona

    2015-06-01

    Full Text Available Livestock effluents are a beneficial nutrient supply for crops, whereby their use is critical to ensure the sustainability of the farms global management. However, they can cause serious ecological problems if misused, polluting soils and groundwater. Combining “soft technology” and local materials is a low cost solution in terms of finance and energy. The REAGUA project (REuso AGUA, Water reuse in Spanish analyzes the possibility of using “picon” (lapilli as a material for the treatment of liquid manure from ruminants, for later use in subsurface drip irrigation system to produce forage and biofuels, in which the soil acts as a subsequent advanced treatment. A three-phase system, in which the effluent was poured with a vertical subsurface flow in an unsaturated medium, is designed. In order to determine the management conditions that optimize the filter, it was necessary to characterize the hydraulic behavior of lapilli and its ability to remove substances. Using three lapilli-filled columns, unsaturated flux, and a ruminant effluent, the reduction of chemical oxygen demand (COD, biochemical oxygen demand after 5 days (BOD5 and ammonia, phosphorus and suspension solids (SS obtained was over 80%, 90%, and 95% respectively, assumable values for irrigation.

  2. The chemical behavior of the transuranic elements and the barrier function in natural aquifer systems

    International Nuclear Information System (INIS)

    Jewett, J.R.

    1997-01-01

    In a geological repository for long-lived radioactive wastes, such as actinides and certain fission products, most of the stored radionuclides remain immobile in the particular geological formation. If any of these could possibly become mobile, only trace concentrations of a few radionuclides would result. Nevertheless, with an inventory in the repository of many tonnes of transuranic elements, the amounts that could disperse cannot be neglected. A critical assessment of the chemical behavior of these nuclides, especially their migration properties in the aquifer system around the repository site, is mandatory for analysis of the long-term safety. The chemistry requited for this includes many geochemical multicomponent reactions that are so far only partially understood and hich therefore can be quantified only incompletely. A few of these reactions have been discussed in this paper based on present knowledge. If a comprehensive discussion of the subject is impossible because of this ack of information then an attempt to emphasize the importance of the predominant geochemical reactions of the transuranic elements in various aquifer systems should be made

  3. Influence of GABA and GABA-producing Lactobacillus brevis DPC 6108 on the development of diabetes in a streptozotocin rat model.

    Science.gov (United States)

    Marques, T M; Patterson, E; Wall, R; O'Sullivan, O; Fitzgerald, G F; Cotter, P D; Dinan, T G; Cryan, J F; Ross, R P; Stanton, C

    2016-06-01

    The aim of this study was to investigate if dietary administration of γ-aminobutyric acid (GABA)-producing Lactobacillus brevis DPC 6108 and pure GABA exert protective effects against the development of diabetes in streptozotocin (STZ)-induced diabetic Sprague Dawley rats. In a first experiment, healthy rats were divided in 3 groups (n=10/group) receiving placebo, 2.6 mg/kg body weight (bw) pure GABA or L. brevis DPC 6108 (~10(9)microorganisms). In a second experiment, rats (n=15/group) were randomised to five groups and four of these received an injection of STZ to induce type 1 diabetes. Diabetic and non-diabetic controls received placebo [4% (w/v) yeast extract in dH2O], while the other three diabetic groups received one of the following dietary supplements: 2.6 mg/kg bw GABA (low GABA), 200 mg/kg bw GABA (high GABA) or ~10(9) L. brevis DPC 6108. L. brevis DPC 6108 supplementation was associated with increased serum insulin levels (Pfood intake. Insulin was decreased (P0.05), compared with non-diabetic controls while all other diabetic groups displayed reduced diversity (P<0.05). L. brevis DPC 6108 attenuated hyperglycaemia induced by diabetes but additional studies are needed to understand the mechanisms involved in this reduction.

  4. Biochemical and molecular characterization of a serine keratinase from Brevibacillus brevis US575 with promising keratin-biodegradation and hide-dehairing activities.

    Directory of Open Access Journals (Sweden)

    Nadia Zaraî Jaouadi

    Full Text Available Dehairing is one of the highly polluting operations in the leather industry. The conventional lime-sulfide process used for dehairing produces large amounts of sulfide, which poses serious toxicity and disposal problems. This operation also involves hair destruction, a process that leads to increased chemical oxygen demand (COD, biological oxygen demand (BOD, and total suspended solid (TSS loads in the effluent. With these concerns in mind, enzyme-assisted dehairing has often been proposed as an alternative method. The main enzyme preparations so far used involved keratinases. The present paper reports on the purification of an extracellular keratinase (KERUS newly isolated from Brevibacillus brevis strain US575. Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS analysis revealed that the purified enzyme was a monomer with a molecular mass of 29121.11 Da. The sequence of the 27 N-terminal residues of KERUS showed high homology with those of Bacillus keratinases. Optimal activity was achieved at pH 8 and 40°C. Its thermoactivity and thermostability were upgraded in the presence of 5 mM Ca(2+. The enzyme was completely inhibited by phenylmethanesulfonyl fluoride (PMSF and diiodopropyl fluorophosphates (DFP, which suggests that it belongs to the serine protease family. KERUS displayed higher levels of hydrolysis, substrate specificity, and catalytic efficiency than NUE 12 MG and KOROPON® MK EG keratinases. The enzyme also exhibited powerful keratinolytic activity that made it able to accomplish the entire feather-biodegradation process on its own. The kerUS gene encoding KERUS was cloned, sequenced, and expressed in Escherichia coli. The biochemical properties of the extracellular purified recombinant enzyme (rKERUS were similar to those of native KERUS. Overall, the findings provide strong support for the potential candidacy of this enzyme as an effective and eco-friendly alternative to the conventional

  5. Tracking ultrasonically structural changes of natural aquatic organic carbon: Chemical fractionation and spectroscopic approaches.

    Science.gov (United States)

    Al-Juboori, Raed A; Yusaf, Talal; Aravinthan, Vasantha; Bowtell, Leslie

    2016-02-01

    In this study, the structural alteration to DOC for a range of ultrasound treatments was investigated with chemical fractionation and UV-vis spectroscopic measurement. Ultrasound treatments were applied in continuous and pulsed modes at power levels of 48 and 84 W for effective treatment times of 5 and 15 min. Overall results show that the ultrasound treatments tended to degrade the hydrophobic aromatic fraction, while increasing the hydrophilic fraction to a lesser extent. The highest recorded reduction of hydrophobic DOC (17.8%) was achieved with pulse treatment of 84 W for15 min, while the highest increase in the hydrophilic DOC (10.5%) was obtained with continuous treatment at 84 W and 5 min. The optimal ultrasound treatment conditions were found to be pulse mode at high power and short treatment time, causing a minimal increase in the hydrophilic fraction of 1.3% with moderate removal of the hydrophobic fraction of 15.52%. The same treatment conditions, with longer treatment time, resulted in the highest removal of SUVA254 and SUVA280 of 17.09% and 16.93, respectively. These results indicate the potential for ultrasound treatments in DOC structural alteration. The hydrophobic fraction showed strong and significant correlations with UV absorbance at 254 and 280 nm. A254/A204 also exhibited strong and significant correlations with the hydrophobic/hydrophilic ratio. The other UV ratios (A250/A365 (E2/E3) and A254/A436) had weak and insignificant correlations with the hydrophobic/hydrophilic ratio. This confirms the applicability of UV indices as a suitable surrogate method for estimating the hydrophobic/hydrophilic structure. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Training of panellists for the sensory control of bottled natural mineral water in connection with water chemical properties.

    Science.gov (United States)

    Rey-Salgueiro, Ledicia; Gosálbez-García, Aitana; Pérez-Lamela, Concepción; Simal-Gándara, Jesús; Falqué-López, Elena

    2013-11-01

    As bottled mineral water market is increasing in the world (especially in emergent and developed countries), the development of a simple protocol to train a panel to evaluate sensory properties would be a useful tool for natural drinking water industry. A sensory protocol was developed to evaluate bottled natural mineral water (17 still and 10 carbonated trademarks). The tasting questionnaire included 13 attributes for still water plus overall impression and they were sorted by: colour hues, transparency and brightness, odour/aroma and taste/flavour/texture and 2 more for carbonated waters (bubbles and effervescence). The training lasted two months with, at least, 10 sessions, was adequate to evaluate bottled natural mineral water. To confirm the efficiency of the sensory training procedure two sensory groups formed the whole panel. One trained panel (6 persons) and one professional panel (6 sommeliers) and both participated simultaneously in the water tasting evaluation of 3 sample lots. Similar average scores obtained from trained and professional judges, with the same water trademarks, confirmed the usefulness of the training protocol. The differences obtained for trained panel in the first lot confirm the necessity to train always before a sensory procedure. A sensory water wheel is proposed to guide the training in bottled mineral water used for drinking, in connection with their chemical mineral content. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. POSSIBLE NATURE OF THE RADIATION-INDUCED SIGNAL IN NAILS: HIGH-FIELD EPR, CONFIRMING CHEMICAL SYNTHESIS, AND QUANTUM CHEMICAL CALCULATIONS.

    Science.gov (United States)

    Tipikin, Dmitriy S; Swarts, Steven G; Sidabras, Jason W; Trompier, François; Swartz, Harold M

    2016-12-01

    Exposure of finger- and toe-nails to ionizing radiation generates an Electron Paramagnetic Resonance (EPR) signal whose intensity is dose dependent and stable at room temperature for several days. The dependency of the radiation-induced signal (RIS) on the received dose may be used as the basis for retrospective dosimetry of an individual's fortuitous exposure to ionizing radiation. Two radiation-induced signals, a quasi-stable (RIS2) and stable signal (RIS5), have been identified in nails irradiated up to a dose of 50 Gy. Using X-band EPR, both RIS signals exhibit a singlet line shape with a line width around 1.0 mT and an apparent g-value of 2.0044. In this work, we seek information on the exact chemical nature of the radiation-induced free radicals underlying the signal. This knowledge may provide insights into the reason for the discrepancy in the stabilities of the two RIS signals and help develop strategies for stabilizing the radicals in nails or devising methods for restoring the radicals after decay. In this work an analysis of high field (94 GHz and 240 GHz) EPR spectra of the RIS using quantum chemical calculations, the oxidation-reduction properties and the pH dependence of the signal intensities are used to show that spectroscopic and chemical properties of the RIS are consistent with a semiquinone-type radical underlying the RIS. It has been suggested that semiquinone radicals formed on trace amounts of melanin in nails are the basis for the RIS signals. However, based on the quantum chemical calculations and chemical properties of the RIS, it is likely that the radicals underlying this signal are generated from the radiolysis of L-3,4-dihydroxyphenylalanine (DOPA) amino acids in the keratin proteins. These DOPA amino acids are likely formed from the exogenous oxidation of tyrosine in keratin by the oxygen from the air prior to irradiation. We show that these DOPA amino acids can work as radical traps, capturing the highly reactive and unstable sulfur

  8. POSSIBLE NATURE OF THE RADIATION-INDUCED SIGNAL IN NAILS: HIGH-FIELD EPR, CONFIRMING CHEMICAL SYNTHESIS, AND QUANTUM CHEMICAL CALCULATIONS

    Science.gov (United States)

    Tipikin, Dmitriy S.; Swarts, Steven G.; Sidabras, Jason W.; Trompier, François; Swartz, Harold M.

    2016-01-01

    Exposure of finger- and toe-nails to ionizing radiation generates an Electron Paramagnetic Resonance (EPR) signal whose intensity is dose dependent and stable at room temperature for several days. The dependency of the radiation-induced signal (RIS) on the received dose may be used as the basis for retrospective dosimetry of an individual's fortuitous exposure to ionizing radiation. Two radiation-induced signals, a quasi-stable (RIS2) and stable signal (RIS5), have been identified in nails irradiated up to a dose of 50 Gy. Using X-band EPR, both RIS signals exhibit a singlet line shape with a line width around 1.0 mT and an apparent g-value of 2.0044. In this work, we seek information on the exact chemical nature of the radiation-induced free radicals underlying the signal. This knowledge may provide insights into the reason for the discrepancy in the stabilities of the two RIS signals and help develop strategies for stabilizing the radicals in nails or devising methods for restoring the radicals after decay. In this work an analysis of high field (94 GHz and 240 GHz) EPR spectra of the RIS using quantum chemical calculations, the oxidation–reduction properties and the pH dependence of the signal intensities are used to show that spectroscopic and chemical properties of the RIS are consistent with a semiquinone-type radical underlying the RIS. It has been suggested that semiquinone radicals formed on trace amounts of melanin in nails are the basis for the RIS signals. However, based on the quantum chemical calculations and chemical properties of the RIS, it is likely that the radicals underlying this signal are generated from the radiolysis of L-3,4-dihydroxyphenylalanine (DOPA) amino acids in the keratin proteins. These DOPA amino acids are likely formed from the exogenous oxidation of tyrosine in keratin by the oxygen from the air prior to irradiation. We show that these DOPA amino acids can work as radical traps, capturing the highly reactive and unstable

  9. Impaired growth in the polychaete Armandia brevis exposed to tributyltin in sediment.

    Science.gov (United States)

    Meador, J P; Rice, C A

    2001-03-01

    Juveniles of the opheliid polychaete, Armandia brevis, were exposed to sediment-associated tributyltin (TBT) for 42 days to evaluate toxicity and bioaccumulation. Growth in this species was inhibited in a dose-response fashion by increasing concentrations of TBT. Even though the biota-sediment accumulation factor (BSAF) for TBT declined for the higher sediment concentrations, the total butyltins in tissue increased over all sediment concentrations. At the highest sediment concentrations, polychaetes bioaccumulated less TBT than expected, which was most likely due to reduced uptake and continued metabolism of the parent compound. The less than expected BSAF values exhibited by animals at the exposure concentrations causing severe effects are an important finding for assessing responses in the field. It appears that severe biological effects can occur in long-term experiments without the expected high tissue concentrations; an observation likely explained by altered toxicokinetics. Analysis of variance determined the lowest observed effect concentration for growth to be 191 ng/g sediment dry wt. for 21 days of exposure and 101 ng/g sediment dry wt. at day 42, indicating that 21 days was insufficient for delineating the steady-state toxicity response. When based on regression analysis, the sediment concentration causing a 25% inhibition in growth at 42 days exposure was 93 ng/g dry wt. (total organic carbon = 0.58%). A dose-response association was also determined for polychaete net weight and TBT in tissue. The tissue residue associated with a 25% reduction in growth was 2834 ng/g dry wt. at day 42. A comparison of these results with previous work indicates that juveniles are approximately three times more sensitive than adults to TBT exposure. The sediment concentrations affecting growth in this species are commonly found in urban waterways indicating potentially severe impacts for this and other sensitive species.

  10. Dextran-Catechin: An anticancer chemically-modified natural compound targeting copper that attenuates neuroblastoma growth

    Science.gov (United States)

    Vittorio, Orazio; Brandl, Miriam; Cirillo, Giuseppe; Kimpton, Kathleen; Hinde, Elizabeth; Gaus, Katharina; Yee, Eugene; Kumar, Naresh; Duong, Hien; Fleming, Claudia; Haber, Michelle; Norris, Murray; Boyer, Cyrille; Kavallaris, Maria

    2016-01-01

    Neuroblastoma is frequently diagnosed at advanced stage disease and treatment includes high dose chemotherapy and surgery. Despite the use of aggressive therapy survival rates are poor and children that survive their disease experience long term side effects from their treatment, highlighting the need for effective and less toxic therapies. Catechin is a natural polyphenol with anti-cancer properties and limited side effects, however its mechanism of action is unknown. Here we report that Dextran-Catechin, a conjugated form of catechin that increases serum stability, is preferentially and markedly active against neuroblastoma cells having high levels of intracellular copper, without affecting non-malignant cells. Copper transporter 1 (CTR1) is the main transporter of copper in mammalian cells and it is upregulated in neuroblastoma. Functional studies showed that depletion of CTR1 expression reduced intracellular copper levels and led to a decrease in neuroblastoma cell sensitivity to Dextran-Catechin, implicating copper in the activity of this compound. Mechanistically, Dextran-Catechin was found to react with copper, inducing oxidative stress and decreasing glutathione levels, an intracellular antioxidant and regulator of copper homeostasis. In vivo, Dextran-Catechin significantly attenuated tumour growth in human xenograft and syngeneic models of neuroblastoma. Thus, Dextran-Catechin targets copper, inhibits tumour growth, and may be valuable in the treatment of aggressive neuroblastoma and other cancers dependent on copper for their growth. PMID:27374085

  11. Chemical behaviour of americium in natural aquatic solutions: Hydrolysis, radiolysis and redox reactions

    International Nuclear Information System (INIS)

    Stadler, S.; Kim, J.I.

    1988-06-01

    Hydrolysis and redox reactions of the Am(III) and Am(V) ions have been investigated in NaClO 4 and NaCl solutions as well as in natural saline groundwaters. The hydrolysis constants of Am(OH) n 3-n species and the solubility product of Am(OH) 3 (s) have been determined in 0.1 M NaClO 4 , 0.1 M NaCl and 0.6 M NaCl solutions. As observed in concentrated NaCl solutions (> 3 M), the α-radiation induces the radiolytic oxidation of the Cl - -ion to produce Cl 2 , HClO, ClO - and other oxidized species, which result in a strongly oxidizing medium. Consequently Am(III) is oxidized to Am(V). Under these conditions the hydrolysis constants of AmO 2 (OH) n 1-n species and the solubility product are also determined. The α-radiation induced radiolysis reactions in NaCl solution and the subsequent oxidation reaction of Am(III) have been systematically investigated by varying pH, NaCl concentration and specific α-activity. Also included in the investigation are a few selected groundwaters of relatively high salinity from the Gorleben aquifer systems. (orig.) [de

  12. Methyl chloride via oxyhydrochlorination of methane: A building block for chemicals and fuels from natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Benson, R.L.; Brown, S.S.D.; Ferguson, S.P.; Jarvis, R.F. Jr. [Dow Corning Corp., Carrollton, KY (United States)

    1995-12-31

    The objectives of this program are to (a) develop a process for converting natural gas to methyl chloride via an oxyhydrochlorination route using highly selective, stable catalysts in a fixed-bed, (b) design a reactor capable of removing the large amount of heat generated in the process so as to control the reaction, (c) develop a recovery system capable of removing the methyl chloride from the product stream and (d) determine the economics and commercial viability of the process. The general approach has been as follows: (a) design and build a laboratory scale reactor, (b) define and synthesize suitable OHC catalysts for evaluation, (c) select first generation OHC catalyst for Process Development Unit (PDU) trials, (d) design, construct and startup PDU, (e) evaluate packed bed reactor design, (f) optimize process, in particular, product recovery operations, (g) determine economics of process, (h) complete preliminary engineering design for Phase II and (i) make scale-up decision and formulate business plan for Phase II. Conclusions regarding process development and catalyst development are presented.

  13. natural

    Directory of Open Access Journals (Sweden)

    Elías Gómez Macías

    2006-01-01

    Full Text Available Partiendo de óxido de magnesio comercial se preparó una suspensión acuosa, la cual se secó y calcinó para conferirle estabilidad térmica. El material, tanto fresco como usado, se caracterizó mediante DRX, área superficial BET y SEM-EPMA. El catalizador mostró una matriz de MgO tipo periclasa con CaO en la superficie. Las pruebas de actividad catalítica se efectuaron en lecho fijo empacado con partículas obtenidas mediante prensado, trituración y clasificación del material. El flujo de reactivos consistió en mezclas gas natural-aire por debajo del límite inferior de inflamabilidad. Para diferentes flujos y temperaturas de entrada de la mezcla reactiva, se midieron las concentraciones de CH4, CO2 y CO en los gases de combustión con un analizador de gases tipo infrarrojo no dispersivo (NDIR. Para alcanzar conversión total de metano se requirió aumentar la temperatura de entrada al lecho a medida que se incrementó el flujo de gases reaccionantes. Los resultados obtenidos permiten desarrollar un sistema de combustión catalítica de bajo costo con un material térmicamente estable, que promueva la alta eficiencia en la combustión de gas natural y elimine los problemas de estabilidad, seguridad y de impacto ambiental negativo inherentes a los procesos de combustión térmica convencional.

  14. Apoptotic role of natural isothiocyanate from broccoli (Brassica oleracea italica) in experimental chemical lung carcinogenesis.

    Science.gov (United States)

    Kalpana Deepa Priya, D; Gayathri, R; Gunassekaran, G R; Murugan, S; Sakthisekaran, D

    2013-05-01

    Sulforaphane (SFN) [1-isothiocyanato-4-(methylsulfinyl)butane] is a naturally occurring isothiocyanate found in cruciferous vegetables such as broccoli [Brassica oleracea L. var. italica Plenck. (Brassicaceae)]. Since it is among the most potent bioactive components with antioxidant and antitumor properties, it has received intense attention in the recent years for its chemopreventive properties. The present work determined the rehabilitating role in alleviating the oxidative damage caused by benzo(a)pyrene [B(a)P] to biomolecules and the apoptotic cascade mediated by orally administered isothiocyanate-SFN (9 µmol/mouse/day) against B(a)P (100 mg/kg body weight, i.p.) induced pulmonary carcinogenesis in Swiss albino mice. Oxidative damage was assessed by measuring lipid peroxidation, 8-hydroxydeoxyguanosine, hydrogen peroxide (H2O2) production, glycoprotein components, protein carbonyl levels and DNA-protein crosslinks. DNA fragmentation by agarose gel electrophoresis and caspase-3 activity by ELISA proved apoptotic induction by SFN along with the protein expression of Bcl-2, Bax and Cyt c. SFN treatment was found to decrease the H2O2 production (p < 0.001) in cancer induced animals, proving its antioxidant potential. Apoptosis was induced by increasing the release of Cyt c (p < 0.001) from mitochondria, decreasing and increasing the expression of Bcl-2 (p < 0.01) and Bax (p < 0.001), respectively. Caspase-3 activity was also enhanced (p < 0.001) which leads to DNA fragmentation in SFN treated groups. Our results reflect the rehabilitating role of SFN in B(a)P induced lung carcinogenesis.

  15. On the physical nature and chemical utility of Kohn-Sham orbitals

    International Nuclear Information System (INIS)

    Baerends, E.J.

    1996-01-01

    Density functional calculations almost invariably use the one-electron Kohn-Sham orbitals to calculate the electron density. It is sometimes stated that these KS orbitals have no special physical meaning, but are constructs, arising in the KS formulation of DFT, that are only useful to obtain the density. We will argue that on the contrary the KS orbitals are often very similar to the molecular orbitals that arise in the Hartree-Fock model. When they differ the Kohn-Sham orbitals have certain advantageous properties and correspond in fact more closely to the orbitals used explicitly or implicitly in qualitative MO theory. The arguments of QMO theory, with their emphasis on bonding and antibonding nature of MOs, do hold perfectly for KS orbitals. The reason that Kohn-Sham orbitals are meaningful objects is related to the fact that the effective one-electron Kohn-Sham potential embodies the effects of electron correlation. It has recently become possible to calculate accurate Kohn-Sham potentials from accurate electron densities. This offers the possibility to study the structure of KS potentials (steps, peaks) and to relate this structure to electron correlation. More importantly, given exact Kohn-Sham potentials and orbitals it is possible to construct an exchange-correlation energy density that will, after integration over space, yield the exact exchange-correlation energy. It is possible to relate the local features of the exact energy density to aspects of electron correlation. The exact energy density may be used to judge existing model exchange-correlation energy densities and hopefully it will be helpful to devise improvements

  16. Laboratory bioassays to estimate the lethal and sublethal effects of various insecticides and fungicides on Deraeocoris brevis (Hemiptera: Miridae).

    Science.gov (United States)

    Amarasekare, K G; Shearer, P W

    2013-04-01

    This laboratory bioassay focused on lethal and sublethal effects of five insecticides (chlorantraniliprole, cyantraniliprole, spinetoram, novaluron, and lambda-cyhalothrin) and two fungicide treatments (sulfur and a mixture of copper hydroxide and mancozeb) on the predatory mired bug, Deraeocoris brevis (Uhler) (Hemiptera: Miridae) using second instars and adult males and females. Formulated pesticides were tested using concentrations that were equivalent to the high label rate (1x) (high rate) and 1/10th of that amount (0.1x) (low rate) dissolved in 378.5 liters of water. Lambda-cyhalothrin was highly toxic to D. brevis nymphs and adults at both rates, whereas both rates of novaluron were highly toxic to nymphs. Cyantraniliprole, chlorantraniliprole, and novaluron were less toxic to adults, and chlorantraniliprole and spinetoram were less toxic to nymphs. Both rates of spinetoram caused significant mortality to adults. Fecundity of adult females was affected negatively by the high rates of either novaluron or spinetoram, whereas the fertility was affected only by the high rate of novaluron. The high rate of spinetoram reduced survival of nymphs. Adults treated with spinetoram had reduced longevity. Cyantraniliprole caused some mortality to nymphs and affected their survival. Both rates of sulfur were toxic to nymphs and affected emergence to adults. The mixture of copper hydroxide and mancozeb was less toxic to D. brevis. Neither adult longevity nor sex ratio was affected by the fungicides. The r values for D. brecis treated with lambda-cyhalothrin, novaluron, spinetoram, and sulfur were low, indicating that these products may have negative impact on population growth.

  17. Shell structure of natural rubber particles: evidence of chemical stratification by electrokinetics and cryo-TEM.

    Science.gov (United States)

    Rochette, Christophe N; Crassous, Jérôme J; Drechsler, Markus; Gaboriaud, Fabien; Eloy, Marie; de Gaudemaris, Benoît; Duval, Jérôme F L

    2013-11-26

    The interfacial structure of natural rubber (NR) colloids is investigated by means of cryogenic transmission electron microscopy (cryo-TEM) and electrokinetics over a broad range of KNO3 electrolyte concentrations (4-300 mM) and pH values (1-8). The asymptotic plateau value reached by NR electrophoretic mobility (μ) in the thin double layer limit supports the presence of a soft (ion- and water-permeable) polyelectrolytic type of layer located at the periphery of the NR particles. This property is confirmed by the analysis of the electron density profile obtained from cryo-TEM that evidences a ∼2-4 nm thick corona surrounding the NR polyisoprene core. The dependence of μ on pH and salt concentration is further marked by a dramatic decrease of the point of zero electrophoretic mobility (PZM) from 3.6 to 0.8 with increasing electrolyte concentration in the range 4-300 mM. Using a recent theory for electrohydrodynamics of soft multilayered particles, this "anomalous" dependence of the PZM on electrolyte concentration is shown to be consistent with a radial organization of anionic and cationic groups across the peripheral NR structure. The NR electrokinetic response in the pH range 1-8 is indeed found to be equivalent to that of particles surrounded by a positively charged ∼3.5 nm thick layer (mean dissociation pK ∼ 4.2) supporting a thin and negatively charged outermost layer (0.6 nm in thickness, pK ∼ 0.7). Altogether, the strong dependence of the PZM on electrolyte concentration suggests that the electrostatic properties of the outer peripheral region of the NR shell are mediated by lipidic residues protruding from a shell containing a significant amount of protein-like charges. This proposed NR shell interfacial structure questions previously reported NR representations according to which the shell consists of either a fully mixed lipid-protein layer, or a layer of phospholipids residing exclusively beneath an outer proteic film.

  18. Structural chemical analysis of liquid metals based on discrete nature studies of changes in physical properties

    International Nuclear Information System (INIS)

    Filippov, E.S.

    1976-01-01

    In terms of a theory of liquid metals which is based upon a notion of spheric groups disintegrating according to the melting type a coordination number (K) for 22 metals is calculated from the type of packing in groups (Ksub(T)) and a computed statistical packing (Ksub(s.p.) = 6.5 - 4.5). The diffraction K is presented as a sum of Ksub(T) and Ksub(s.p.) groups. Packing type in Ksub(T) groups is established by experiments on density as a function of temperature, which has revealed the stage (discrete) nature of density changes. The ratio between the temperature of the beginning and termination of a stage is equal to the packing coefficient in a group (0.74; 0,68; 0.50). For densely packed groups at Tsub(m(it is shown that K)sub(l) = 0.74 Ksub(T + 0.26XKsub(s.p.) (if Ksub(T) = 12, Ksub(l) = 10.4). If the number of splitting stages (p) is less than three, then Ksub(l) = 0.74 2 Ksub(T) + 2(1 - 0.74 2 ) Ksub(s.p.) When Ksub(T) = 8 (for alkaline metals and iron), Ksub(l) = 9.5. It has been found for liquid inert groups that Ksub(l) = 8.7. Liquid Sn and Bi prove to be a mixture of densest cubic (d.c.) and volume-centred cubic (v.c.c.) groups. The fractions of each group have been calculated; Bi consists of 30% v.c.c. and 70% d.c., Sn of 54% d.c. and 46% v.c.c. grouops. The diffraction (total) K in liquid metals appears to be a parameter different from K in solid ones, being a function of structural components of the groups and packing of atoms between the groups, rather than a definite characteristic of liquid metals structure

  19. A mobile sampler for mesuring the concentration of radionuclides and their physico chemical forms in natural waters

    International Nuclear Information System (INIS)

    Spezzano, P.; Giacomelli, R.; Bortoluzzi, S.; Montealto, M.; Nocente, M.

    1990-01-01

    This paper describes the realization of a sampler for concentrating radionuclides from large volume of natural waters with the purpose to determine their concentration levels and their physico-chemical forms. Sample is pumped at a flow rate of about 0.5 m 3 /h through a set of sequential filters with different pore sizes to achieve separation of 'particulate' from 'dissolved' forms. Filtered samples is then passed through sequential beds of cation and anion exchange resins and activated alumina to obtain separation of dissolved forms on the basis of their charge. Ammonium Hexacianocobalt Ferrate (NCFC is used as a selective exchanger for Cesium isotopes. Filter and exchangers are measured by computerized gamma spectrometry. Detection limits are of a few tenths of Bq per cubic meter of sample. The main results obtained during radioecological surveys are also presented

  20. 210Pb content in natural gas pipeline residues ('black-powder') and its correlation with the chemical composition

    International Nuclear Information System (INIS)

    Godoy, Jose Marcus; Carvalho, Franciane; Cordilha, Aloisio; Matta, Luiz Ernesto; Godoy, Maria Luiza

    2005-01-01

    The present work was carried out to assess the 210 Pb content in 'black-powder' found in pigging operations on gas pipelines in Brazil, in particular, on the Campos Basin gas pipeline. Additionally, the chemical composition of such deposits was determined and an eventual correlation with 210 Pb concentration evaluated. Typical 'black-powder' generated in the natural gas pipeline from Campos Basin oilfield contains mainly iron oxide (∼81%) and residual organic matter (∼9%). The 210 Pb content ranges from 4.9 to 0.04 kBq kg -1 and seems to be inversely correlated with the distance to the platforms. On the other hand, 226 Ra concentration is higher on the pipeline branch between the platform and the onshore installations. 228 Ra was only observed in few samples, in particular, in the samples with the highest 226 Ra content

  1. Antidotal or protective effects of Curcuma longa (turmeric) and its active ingredient, curcumin, against natural and chemical toxicities: A review.

    Science.gov (United States)

    Hosseini, Azar; Hosseinzadeh, Hossein

    2018-03-01

    Curcuma longa is a rhizomatous perennial herb that belongs to the family Zingiberaceae, native to South Asia and is commonly known as turmeric. It is used as herbal remedy due to the prevalent belief that the plant has medical properties. C. longa possesses different effects such as antioxidant, anti-tumor, antimicrobial, anti-inflammatory, wound healing, and gastroprotective activities. The recent studies have shown that C. longa and curcumin, its important active ingredient, have protective effects against toxic agents. In this review article, we collected in vitro and animal studies which are related to protective effects of turmeric and its active ingredient against natural and chemical toxic agents. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  2. [Physico-chemical features of dinitrosyl iron complexes with natural thiol-containing ligands underlying biological activities of these complexes].

    Science.gov (United States)

    Vanin, A F; Borodulin, R R; Kubrina, L N; Mikoian, V D; Burbaev, D Sh

    2013-01-01

    Current notions and new experimental data of the authors on physico-chemical features of dinitrosyl iron complexes with natural thiol-containing ligands (glutathione or cysteine), underlying the ability of the complexes to act as NO molecule and nitrosonium ion donors, are considered. This ability determines various biological activities of dinitrosyl iron complexes--inducing long-lasting vasodilation and thereby long-lasting hypotension in human and animals, inhibiting pellet aggregation, increasing red blood cell elasticity, thereby stimulating microcirculation, and reducing necrotic zone in animals with myocardial infarction. Moreover, dinitrosyl iron complexes are capable of accelerating skin wound healing, improving the function of penile cavernous tissue, blocking apoptosis development in cell cultures. When decomposed dinitrosyl iron complexes can exert cytotoxic effect that can be used for curing infectious and carcinogenic pathologies.

  3. Effect of methionine and cysteine deprivation on growth of different natural isolates of Lactobacillus spp. in chemically defined media

    Directory of Open Access Journals (Sweden)

    Lozo Jelena

    2008-01-01

    Full Text Available The purpose of this study was to determine the ability of natural isolates of lactobacilli from different ecological niches to grow in a chemically defined medium in the presence or absence of sulphur-containing amino acids, methionine and/or cysteine. The obtained results indicate that cysteine is essential for growth of L. paracasei subsp. paracasei BGHN14 and BGSJ2-8, while methionine is essential for isolates BGHN40, BGCG31, and BGHV54T of the species L. plantarum. Methionine is also essential for growth of L. rhamnosus BGHV58T. Other analyzed strains, such as L. plantarum BGSJ3-18, BGZB19, BGHV52Ta, and BGHV43T, require the presence of both amino acids for their growth.

  4. The Gas-Absorption/Chemical-Reaction Method for Measuring Air-Water Interfacial Area in Natural Porous Media

    Science.gov (United States)

    Lyu, Ying; Brusseau, Mark L.; El Ouni, Asma; Araujo, Juliana B.; Su, Xiaosi

    2017-11-01

    The gas-absorption/chemical-reaction (GACR) method used in chemical engineering to quantify gas-liquid interfacial area in reactor systems is adapted for the first time to measure the effective air-water interfacial area of natural porous media. Experiments were conducted with the GACR method, and two standard methods (X-ray microtomographic imaging and interfacial partitioning tracer tests) for comparison, using model glass beads and a natural sand. The results of a series of experiments conducted under identical conditions demonstrated that the GACR method exhibited excellent repeatability for measurement of interfacial area (Aia). Coefficients of variation for Aia were 3.5% for the glass beads and 11% for the sand. Extrapolated maximum interfacial areas (Am) obtained with the GACR method were statistically identical to independent measures of the specific solid surface areas of the media. For example, the Am for the glass beads is 29 (±1) cm-1, compared to 32 (±3), 30 (±2), and 31 (±2) cm-1 determined from geometric calculation, N2/BET measurement, and microtomographic measurement, respectively. This indicates that the method produced accurate measures of interfacial area. Interfacial areas determined with the GACR method were similar to those obtained with the standard methods. For example, Aias of 47 and 44 cm-1 were measured with the GACR and XMT methods, respectively, for the sand at a water saturation of 0.57. The results of the study indicate that the GACR method is a viable alternative for measuring air-water interfacial areas. The method is relatively quick, inexpensive, and requires no specialized instrumentation compared to the standard methods.

  5. Physico-chemical characterization of terbium-161-chloride (161TbCl3) radioisotope from irradiated natural gadolinium oxide target

    International Nuclear Information System (INIS)

    Azmairit Aziz; Nana Suherman

    2015-01-01

    Currently cancer patients are increasing every year in Indonesia and become the third leading cause of death after heart disease and high blood pressure. Terbium-161 ( 161 Tb) is a low β- emitter (E β - = 0.155 MeV, T 1/2 = 6.9 d) and very similar to 177 Lu in terms of half-life, E β - energy and chemical properties.However, 161 Tb also ejects internal conversion electrons and Auger electrons which can provide a greater therapeutic effect than 177 Lu. Radioisotope of 161 Tb can be produced as a carrier-free for use in labeling of biomolecules as a targeted radiopharmaceutical for cancer therapy. 161 Tb was obtained through 160 Gd(n,γ) 161 Tb nuclear reaction by thermal neutron bombardment on 100 mg of natural gadolinium oxide target in RSG-G.A. Siwabessy at a thermal neutron flux of ~10 14 n.cm -2 .s -1 and followed by radiochemical separation of 161 Tb from Gd isotopes using extraction chromatography method. The physico-chemical characterization of 161 TbCl 3 solution was studied by determination of its radionuclide purity by means of a γ-rays spectrometry with HP-Ge detector coupled to a multichannel analyzer (MCA). Radiochemical purity was determined using paper chromatography and paper electrophoresis methods. The results showed that 161 TbCl 3 radioisotope has a pH of 2, radiochemical purity of 99.64 ± 0.34%, radionuclide purity of 99.69 ± 0.20%, specific activity and radioactive concentration at the end of irradiation (EOI) of 2.26 – 5.31 Ci/mg and 3.84 – 9.03 mCi/mL, respectively. 161 TbCl 3 solution stable for 3 weeks at room temperature with a radiochemical purity of 98.41 ± 0.42%. 161 TbCl 3 solution from irradiated natural gadolinium oxide target has the physico-chemical characteristic that meets the requirements for use as a precursor in preparation of radiopharmaceuticals. (author)

  6. Scientific Opinion on the safety and efficacy of Lactobacillus brevis (DSMZ 16680) as a silage additive for all species

    OpenAIRE

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP)

    2014-01-01

    Lactobacillus brevis is a technological additive intended to improve the ensiling process at a proposed minimum dose of 1.0 × 108 colony-forming units (CFU)/kg fresh material. The bacterial species L. brevis is considered by the European Food Safety Authority to be suitable for the qualified presumption of safety approach to safety assessment. As the identity of the strain has been clearly established and as no antibiotic resistance of concern was detected, the use of the strain in the produc...

  7. To the knowledge of rare species of Acrididae from Protected Areas in North-Western Russia: Chorthippus brunneus brevis (Orthoptera, Acrididae

    Directory of Open Access Journals (Sweden)

    Aleksander A. Benediktov

    2017-05-01

    Full Text Available The presence of the grasshopper Chorthippus brunneus brevis (Orthoptera, Acrididae, Gomphocerinae has been confirmed for the Vyborg district mainland of the Leningrad region, Russia, for the first time since 1908. Information about its habitats, characteristics of morphology, as well as calling signals of males is presented. The differences of the stridulatory file structure in the males of the closely related species Ch. brunneus brunneus, Ch. brunneus brevis and Ch. porphyropterus from the territory of Russia are considered. Information on the difference in calling of both subspecies of Ch. brunneus is given.

  8. Hop Resistance in the Beer Spoilage Bacterium Lactobacillus brevis Is Mediated by the ATP-Binding Cassette Multidrug Transporter HorA

    OpenAIRE

    Sakamoto, Kanta; Margolles, Abelardo; van Veen, Hendrik W.; Konings, Wil N.

    2001-01-01

    Lactobacillus brevis is a major contaminant of spoiled beer. The organism can grow in beer in spite of the presence of antibacterial hop compounds that give the beer a bitter taste. The hop resistance in L. brevis is, at least in part, dependent on the expression of the horA gene. The deduced amino acid sequence of HorA is 53% identical to that of LmrA, an ATP-binding cassette multidrug transporter in Lactococcus lactis. To study the role of HorA in hop resistance, HorA was functionally expre...

  9. Impact of the changes in the chemical composition of pore water on chemical and physical stability of natural clays. A review of natural cases and related laboratory experiments and the ideas on natural analogues for bentonite erosion/non-erosion

    Energy Technology Data Exchange (ETDEWEB)

    Puura, Erik (Eridicon OUe, Tartu (Estonia)); Kirsimaee, Kalle (Univ. of Tartu, Inst. of Ecology and Earth Sciences, Tartu (Estonia))

    2010-01-15

    A scientific literature survey was compiled with the specific objective to find information for smectite mobilization and/or retention in natural clay formations caused by contact with water with low ionic concentrations such as can be expected during and after an ice age. Evidence was sought if smectite particles are lost from the clay to the water and if accessory minerals that remain could form a growing filter slowing down or stopping further loss of smectite. Bentonites are present in geological layers for hundreds of millions of years. There is limited exchange with surrounding layers, eg K transported into the bentonite layer from surrounding shale layers leading to the increased illite % in smectite-illite of the bentonite. Another process is silicification of surrounding layers leading to lowered permeability of surrounding rocks. Geological literature data on historical bentonites do not consider colloid formation in low ionic strength water as relevant mechanism for smectite mobilization. However there are no studied cases where this could be a relevant mechanism (as proposed by colloid release scenario). Soil researchers have studied the mechanism of colloid release in laboratory experiments and have found that there has to be an abrupt change in infiltrating water quality leading to 'osmotic explosion'. Clogging the pores in the lower part of the soil column has followed, leading to dramatic decrease of hydraulic conductivity in vertical profile and increased surface runoff. So, although limited, there are literature evidences of clay colloids release from bentonites/smectites caused by low-ionic circumneutral water. The geological settings to look for natural analogue studies include (1) Bentonite/smectite similar to what is used in repository. (2) Water similar to the composition of glacial meltwater. (3) Scenario similar to what is proposed in the bentonite erosion project. The problem related to the study of historical bentonite profiles

  10. Impact of the changes in the chemical composition of pore water on chemical and physical stability of natural clays. A review of natural cases and related laboratory experiments and the ideas on natural analogues for bentonite erosion/non-erosion

    International Nuclear Information System (INIS)

    Puura, Erik; Kirsimaee, Kalle

    2010-01-01

    A scientific literature survey was compiled with the specific objective to find information for smectite mobilization and/or retention in natural clay formations caused by contact with water with low ionic concentrations such as can be expected during and after an ice age. Evidence was sought if smectite particles are lost from the clay to the water and if accessory minerals that remain could form a growing filter slowing down or stopping further loss of smectite. Bentonites are present in geological layers for hundreds of millions of years. There is limited exchange with surrounding layers, eg K transported into the bentonite layer from surrounding shale layers leading to the increased illite % in smectite-illite of the bentonite. Another process is silicification of surrounding layers leading to lowered permeability of surrounding rocks. Geological literature data on historical bentonites do not consider colloid formation in low ionic strength water as relevant mechanism for smectite mobilization. However there are no studied cases where this could be a relevant mechanism (as proposed by colloid release scenario). Soil researchers have studied the mechanism of colloid release in laboratory experiments and have found that there has to be an abrupt change in infiltrating water quality leading to 'osmotic explosion'. Clogging the pores in the lower part of the soil column has followed, leading to dramatic decrease of hydraulic conductivity in vertical profile and increased surface runoff. So, although limited, there are literature evidences of clay colloids release from bentonites/smectites caused by low-ionic circumneutral water. The geological settings to look for natural analogue studies include (1) Bentonite/smectite similar to what is used in repository. (2) Water similar to the composition of glacial meltwater. (3) Scenario similar to what is proposed in the bentonite erosion project. The problem related to the study of historical bentonite profiles is the

  11. A Natural Analogue for Thermal-Hydrological-Chemical Coupled Processes at the Proposed Nuclear Waste Repository at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Bill Carey; Gordon Keating; Peter C. Lichtner

    1999-01-01

    Dike and sill complexes that intruded tuffaceous host rocks above the water table are suggested as natural analogues for thermal-hydrologic-chemical (THC) processes at the proposed nuclear waste repository at Yucca Mountain, Nevada. Scoping thermal-hydrologic calculations of temperature and saturation profiles surrounding a 30-50 m wide intrusion suggest that boiling conditions could be sustained at distances of tens of meters from the intrusion for several thousand years. This time scale for persistence of boiling is similar to that expected for the Yucca Mountain repository with moderate heat loading. By studying the hydrothermal alteration of the tuff host rocks surrounding the intrusions, insight and relevant data can be obtained that apply directly to the Yucca Mountain repository and can shed light on the extent and type of alteration that should be expected. Such data are needed to bound and constrain model parameters used in THC simulations of the effect of heat produced by the waste on the host rock and to provide a firm foundation for assessing overall repository performance. One example of a possible natural analogue for the repository is the Paiute Ridge intrusive complex located on the northeastern boundary of the Nevada Test Site, Nye County, Nevada. The complex consists of dikes and sills intruded into a partially saturated tuffaceous host rock that has stratigraphic sequences that correlate with those found at Yucca Mountain. The intrusions were emplaced at a depth of several hundred meters below the surface, similar to the depth of the proposed repository. The tuffaceous host rock surrounding the intrusions is hydrothermally altered to varying extents depending on the distance from the intrusions. The Paiute Ridge intrusive complex thus appears to be an ideal natural analogue of THC coupled processes associated with the Yucca Mountain repository. It could provide much needed physical and chemical data for understanding the influence of heat

  12. Low Cost Chemical Feedstocks Using an Improved and Energy Efficient Natural Gas Liquid (NGL) Removal Process, Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Howard, S.; Lu, Yingzhong

    2012-08-10

    The overall objective of this project is to develop a new low-cost and energy efficient Natural Gas Liquid (NGL) recovery process - through a combination of theoretical, bench-scale and pilot-scale testing - so that it could be offered to the natural gas industry for commercialization. The new process, known as the IROA process, is based on U.S. patent No. 6,553,784, which if commercialized, has the potential of achieving substantial energy savings compared to currently used cryogenic technology. When successfully developed, this technology will benefit the petrochemical industry, which uses NGL as feedstocks, and will also benefit other chemical industries that utilize gas-liquid separation and distillation under similar operating conditions. Specific goals and objectives of the overall program include: (i) collecting relevant physical property and Vapor Liquid Equilibrium (VLE) data for the design and evaluation of the new technology, (ii) solving critical R&D issues including the identification of suitable dehydration and NGL absorbing solvents, inhibiting corrosion, and specifying proper packing structure and materials, (iii) designing, construction and operation of bench and pilot-scale units to verify design performance, (iv) computer simulation of the process using commercial software simulation platforms such as Aspen-Plus and HYSYS, and (v) preparation of a commercialization plan and identification of industrial partners that are interested in utilizing the new technology. NGL is a collective term for C2+ hydrocarbons present in the natural gas. Historically, the commercial value of the separated NGL components has been greater than the thermal value of these liquids in the gas. The revenue derived from extracting NGLs is crucial to ensuring the overall profitability of the domestic natural gas production industry and therefore of ensuring a secure and reliable supply in the 48 contiguous states. However, rising natural gas prices have dramatically reduced

  13. Structural and functional anatomy of the palmaris brevis: grasping for answers.

    Science.gov (United States)

    Moore, Colin W; Rice, Charles L

    2017-12-01

    The palmaris brevis (PB) is a small cutaneous hand muscle that has been described as the most mysterious muscle from a functional and developmental perspective [Kaplan () Kaplan's Functional and Surgical Anatomy of the Hand]. Functionally, the PB is considered to deepen the hollow of the palm and to protect the neurovasculature of the ulnar canal. Although the function of the PB has been inferred from cadaveric observations, the electromyographic (EMG) activity of this muscle has not been explored systematically during specific movements of the hand. The purpose of this study was to record PB intramuscular EMG activity during dynamic grasping tasks, and to quantify the change in PB muscle length (M L ) and thickness (M T ) incurred during maximal contraction using ultrasound imaging. Intramuscular EMG was recorded from the PB in the dominant hands of 12 healthy participants (11 males, one female; age: 27 ± 4 years) during maximal abduction, flexion and opposition of the 5th digit, and two grasping tasks. Abduction of the 5th digit yielded the greatest EMG activity in most individuals (seven out of 11), and produced significantly less PB EMG activity when compared with grasping a cylindrical-shaped object (P = 0.003) but not a spherical-shaped object (P = 0.130). During maximal abduction of the 5th digit, PB M L decreased in both the left (28 ± 11%; P = 0.002) and right (32 ± 5%; P = 0.002) hands. Similarly, a concomitant increase in PB M T was observed in the left (68 ± 30%; P = 0.002) and right (85 ± 44%; P = 0.002) hands during the same contraction. These EMG results indicate that the PB is voluntarily activated during prehensile and non-prehensile movements of the hand with significant changes in muscle architecture. The study supports the preservation of the PB in surgical procedures based on its proposed protective role as a muscular barrier to the neurovasculature within the ulnar canal. © 2017 Anatomical Society.

  14. Influence of Chemical Extraction on Rheological Behavior, Viscoelastic Properties and Functional Characteristics of Natural Heteropolysaccharide/Protein Polymer from Durio zibethinus Seed

    Directory of Open Access Journals (Sweden)

    Hamed Mirhosseini

    2012-11-01

    Full Text Available In recent years, the demand for a natural plant-based polymer with potential functions from plant sources has increased considerably. The main objective of the current study was to study the effect of chemical extraction conditions on the rheological and functional properties of the heteropolysaccharide/protein biopolymer from durian (Durio zibethinus seed. The efficiency of different extraction conditions was determined by assessing the extraction yield, protein content, solubility, rheological properties and viscoelastic behavior of the natural polymer from durian seed. The present study revealed that the soaking process had a more significant (p < 0.05 effect than the decolorizing process on the rheological and functional properties of the natural polymer. The considerable changes in the rheological and functional properties of the natural polymer could be due to the significant (p < 0.05 effect of the chemical extraction variables on the protein fraction present in the molecular structure of the natural polymer from durian seed. The natural polymer from durian seed had a more elastic (or gel like behavior compared to the viscous (liquid like behavior at low frequency. The present study revealed that the natural heteropolysaccharide/protein polymer from durian seed had a relatively low solubility ranging from 9.1% to 36.0%. This might be due to the presence of impurities, insoluble matter and large particles present in the chemical structure of the natural polymer from durian seed.

  15. VirtualToxLab — A platform for estimating the toxic potential of drugs, chemicals and natural products

    Energy Technology Data Exchange (ETDEWEB)

    Vedani, Angelo, E-mail: angelo.vedani@unibas.ch [Biographics Laboratory 3R, Klingelbergstrasse 50, 4056 Basel (Switzerland); Department of Pharmaceutical Sciences, University of Basel, Klingelbergstrasse 50, 4056 Basel (Switzerland); Dobler, Max [Biographics Laboratory 3R, Klingelbergstrasse 50, 4056 Basel (Switzerland); Smieško, Martin [Department of Pharmaceutical Sciences, University of Basel, Klingelbergstrasse 50, 4056 Basel (Switzerland)

    2012-06-01

    The VirtualToxLab is an in silico technology for estimating the toxic potential (endocrine and metabolic disruption, some aspects of carcinogenicity and cardiotoxicity) of drugs, chemicals and natural products. The technology is based on an automated protocol that simulates and quantifies the binding of small molecules towards a series of proteins, known or suspected to trigger adverse effects. The toxic potential, a non-linear function ranging from 0.0 (none) to 1.0 (extreme), is derived from the individual binding affinities of a compound towards currently 16 target proteins: 10 nuclear receptors (androgen, estrogen α, estrogen β, glucocorticoid, liver X, mineralocorticoid, peroxisome proliferator-activated receptor γ, progesterone, thyroid α, and thyroid β), four members of the cytochrome P450 enzyme family (1A2, 2C9, 2D6, and 3A4), a cytosolic transcription factor (aryl hydrocarbon receptor) and a potassium ion channel (hERG). The interface to the technology allows building and uploading molecular structures, viewing and downloading results and, most importantly, rationalizing any prediction at the atomic level by interactively analyzing the binding mode of a compound with its target protein(s) in real-time 3D. The VirtualToxLab has been used to predict the toxic potential for over 2500 compounds: the results are posted on (http://www.virtualtoxlab.org). The free platform — the OpenVirtualToxLab — is accessible (in client–server mode) over the Internet. It is free of charge for universities, governmental agencies, regulatory bodies and non-profit organizations. -- Highlights: ► In silico technology for estimating the toxic potential of drugs and chemicals. ► Simulation of binding towards 16 proteins suspected to trigger adverse effects. ► Mechanistic interpretation and real-time 3D visualization. ► Accessible over the Internet. ► Free of charge for universities, governmental agencies, regulatory bodies and NPOs.

  16. In vitro antimicrobial activity of auxiliary chemical substances and natural extracts on Candida albicans and Enterococcus faecalis in root canals

    Directory of Open Access Journals (Sweden)

    Marcia Carneiro Valera

    2013-04-01

    Full Text Available Objective: The aim of this study was to evaluate the antimicrobial activity of auxiliary chemical substances and natural extracts on Candida albicans and Enterococcus faecalis inoculated in root canals. Material and Methods: Seventy-two human tooth roots were contaminated with C. albicans and E. faecalis for 21 days. The groups were divided according to the auxiliary chemical substance into: G1 2.5% sodium hypochlorite (NaOCl, G2 2% chlorhexidine gel (CHX, G3 castor oil, G4 glycolic Aloe vera extract, G5 glycolic ginger extract, and G6 sterile saline (control. The samples of the root canal were collected at different intervals: confirmation collection, at 21 days after contamination; 1st collection, after instrumentation; and 2nd collection, seven days after instrumentation. Microbiological samples were grown in culture medium and incubated at 37°C for 48 hours. Results: The results were submitted to the Kruskal-Wallis and Dunn (5% statistical tests. NaOCl and CHX completely eliminated the microorganisms of the root canals. Castor oil and ginger significantly reduced the number of CFU of the tested bacteria. Reduction of CFU/mL at the 1st and 2nd collections for groups G1, G2, G3 and G4 was greater in comparison to groups G5 and G6. Conclusion: It was concluded that 2.5% sodium hypochlorite and 2% chlorhexidine gel were more effective in eliminating C. albicans and E. faecalis, followed by the castor oil and glycolic ginger extract. The Aloe vera extract showed no antimicrobial activity.

  17. VirtualToxLab — A platform for estimating the toxic potential of drugs, chemicals and natural products

    International Nuclear Information System (INIS)

    Vedani, Angelo; Dobler, Max; Smieško, Martin

    2012-01-01

    The VirtualToxLab is an in silico technology for estimating the toxic potential (endocrine and metabolic disruption, some aspects of carcinogenicity and cardiotoxicity) of drugs, chemicals and natural products. The technology is based on an automated protocol that simulates and quantifies the binding of small molecules towards a series of proteins, known or suspected to trigger adverse effects. The toxic potential, a non-linear function ranging from 0.0 (none) to 1.0 (extreme), is derived from the individual binding affinities of a compound towards currently 16 target proteins: 10 nuclear receptors (androgen, estrogen α, estrogen β, glucocorticoid, liver X, mineralocorticoid, peroxisome proliferator-activated receptor γ, progesterone, thyroid α, and thyroid β), four members of the cytochrome P450 enzyme family (1A2, 2C9, 2D6, and 3A4), a cytosolic transcription factor (aryl hydrocarbon receptor) and a potassium ion channel (hERG). The interface to the technology allows building and uploading molecular structures, viewing and downloading results and, most importantly, rationalizing any prediction at the atomic level by interactively analyzing the binding mode of a compound with its target protein(s) in real-time 3D. The VirtualToxLab has been used to predict the toxic potential for over 2500 compounds: the results are posted on (http://www.virtualtoxlab.org). The free platform — the OpenVirtualToxLab — is accessible (in client–server mode) over the Internet. It is free of charge for universities, governmental agencies, regulatory bodies and non-profit organizations. -- Highlights: ► In silico technology for estimating the toxic potential of drugs and chemicals. ► Simulation of binding towards 16 proteins suspected to trigger adverse effects. ► Mechanistic interpretation and real-time 3D visualization. ► Accessible over the Internet. ► Free of charge for universities, governmental agencies, regulatory bodies and NPOs.

  18. Evolution of the chemical bonding nature and electrode activity of indium selenide upon the composite formation with graphene nanosheets

    International Nuclear Information System (INIS)

    Oh, Seung Mi; Lee, Eunsil; Adpakpang, Kanyaporn; Patil, Sharad B.; Park, Mi Jin; Lim, Young Soo; Lee, Kyu Hyoung; Kim, Jong-Young; Hwang, Seong-Ju

    2015-01-01

    Graphical abstract: Display Omitted -- Highlights: • In 4 Se 2.85 @graphene nanocomposite is easily prepared by high energy mechanical milling process. • The bond covalency of In 4 Se 2.85 is notably changed upon the composite formation with graphene. • In 4 Se 2.85 @graphene nanocomposite shows promising anode performance for lithium ion battery. -- Abstract: Evolution of the chemical bonding nature and electrochemical activity of indium selenide upon the composite formation with carbon species is systematically investigated. Nanocomposites of In 4 Se 2.85 @graphene and In 4 Se 2.85 @carbon-black are synthesized via a solid state reaction between In and Se elements, and the following high energy mechanical milling of In 4 Se 2.85 with graphene and carbon-black, respectively. The high energy mechanical milling (HEMM) of In 4 Se 2.85 with carbon species gives rise to a decrease of particle size with a significant depression of the crystallinity of In 4 Se 2.85 phase. In contrast to the composite formation with carbon-black, that with graphene induces a notable decrease of (In−Se) bond covalency, underscoring significant chemical interaction between graphene and In 4 Se 2.85 . Both the nanocomposites of In 4 Se 2.85 @graphene and In 4 Se 2.85 @carbon-black show much better anode performance for lithium ion batteries with larger discharge capacity and better cyclability than does the pristine In 4 Se 2.85 material, indicating the beneficial effect of composite formation on the electrochemical activity of indium selenide. Between the present nanocomposites, the electrode performance of the In 4 Se 2.85 @graphene nanocomposite is superior to that of the In 4 Se 2.85 @carbon-black nanocomposite, which is attributable to the weakening of (In−Se) bonds upon the composite formation with graphene as well as to the better mixing between In 4 Se 2.85 and graphene. The present study clearly demonstrates that the composite formation with graphene has strong influence

  19. An Introduction to the Foundations of Chemical Information Theory. Tarski–Lesniewski Logical Structures and the Organization of Natural Sorts and Kinds

    Directory of Open Access Journals (Sweden)

    Jerry L. R. Chandler

    2017-01-01

    Full Text Available Organic mathematics is an applied mathematics of philosophical atomism. The order of the chemical elements in the table of elements is the source of order for the logical operations of addition and subtraction of atomic numbers. The inverse square laws of physics are the source of organization of subatomic structures of chemical atoms (atomic and molecular structures. These facts are foundational to the logic of the chemical sciences and are therefore the scientific basis for chemical information theory. The theories and facts of the chemical sciences are so perplex that several forms of symbolic representations are necessary to communicate the broad range of scientific concepts used to inquire into the nature of natural sorts and kinds. The logics proposed by Tarski, Lesniewski and Malatesta are applied to the construction of a numerical “spine” of perplex numbers representing atomic numbers as meta-symbols in meta-languages. The orbital angular momenta of certain collections of electrical particles (also known as “handedness” are critical components in constructing the logical propositions of the perplex number “spine”. Biological communication channels can function if and only if the natural sorts and kinds are consistent with the matching patterns of the optical isomers. The terms spinners and twisters are introduced to express the electro-mechanical torques necessary for encoding chemical information. This hypothesis can be tested by several categories of experiments, including clinical pharmaco-dynamics and clinical toxico-dynamics of dissymmetric isomers of different sorts and kinds.

  20. Differentiation of Lactobacillus brevis strains using Matrix-Assisted-Laser-Desorption-Ionization-Time-of-Flight Mass Spectrometry with respect to their beer spoilage potential.

    Science.gov (United States)

    Kern, Carola C; Vogel, Rudi F; Behr, Jürgen

    2014-06-01

    Lactobacillus (L.) brevis is one of the most frequently encountered bacteria in beer-spoilage incidents. As the species Lactobacillus brevis comprises strains showing varying ability to grow in beer, ranging from growth in low hopped wheat to highly hopped pilsner beer, differentiation and classification of L. brevis with regard to their beer-spoiling ability is of vital interest for the brewing industry. Matrix-Assisted-Laser-Desorption-Ionization-Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) has been shown as a powerful tool for species and sub-species differentiation of bacterial isolates and is increasingly used for strain-level differentiation. Seventeen L. brevis strains, representative of different spoilage types, were characterized according to their tolerance to iso-alpha-acids and their growth in wheat-, lager- and pilsner beer. MALDI-TOF MS spectra were acquired to perform strain-level identification, cluster analysis and biomarker detection. Strain-level identification was achieved in 90% out of 204 spectra. Misidentification occurred nearly exclusively among strains belonging to the same spoilage type. Though spectra of strongly beer-spoiling strains showed remarkable similarity, no decisive single markers were detected to be present in all strains of one group. However, MALDI-TOF MS spectra can be reliably assigned to the corresponding strain and thus allow to track single strains and connect them to their physiological properties. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Effect of ethanol and low pH on citrulline and ornithine excretion and arc gene expression by strains of Lactobacillus brevis and Pediococcus pentosaceus.

    Science.gov (United States)

    Araque, Isabel; Bordons, Albert; Reguant, Cristina

    2013-02-01

    The accumulation of citrulline and ornithine in wine or beer as a result of the arginine catabolism of some lactic acid bacteria (LAB) species increases the risk of ethyl carbamate and putrescine formation, respectively. Several LAB species, which are found as spoilage bacteria in alcoholic beverages, have been reported to be arginine degrading. This study evaluates the effect of ethanol content and low pH on the excretion of citrulline and ornithine by two strains belonging to the potential contaminant species Lactobacillus brevis and Pediococcus pentosaceus. In the conditions that most affected cell viability, arginine consumption per cell increased noticeably, indicating that arginine utilization may be a stress responsive mechanism. L. brevis showed a higher accumulation of ornithine in the media than P. pentosaceus. In the presence of ethanol, a higher expression of the arcC gene was found in P. pentosaceus, which resulted in a lower excretion of citrulline and ornithine than in L. brevis. This suggests that L. brevis is more likely to produce these amino acids, which are precursors of ethyl carbamate and putrescine. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Effect of the gastrointestinal environment on pH homeostasis of Lactobacillus plantarum and Lactobacillus brevis cells as measured by real-time fluorescence ratio-imaging microscopy

    DEFF Research Database (Denmark)

    Ramos, Cíntia Lacerda; Thorsen, Line; Ryssel, Mia

    2014-01-01

    using fluorescence ratio imaging microscopy (FRIM) for potential probiotic strains of Lactobacillus plantarum UFLA CH3 and Lactobacillus brevis UFLA FFC199. Heterogeneous populations were observed, with pHi values ranging from 6.5 to 7.5, 3.5 to 5.6 and 6.5 to 8.0 or higher during passage of saliva (p...

  3. Analysis of Combined Cycle Power Plants with Chemical Looping Reforming of Natural Gas and Pre-Combustion CO2 Capture

    Directory of Open Access Journals (Sweden)

    Shareq Mohd Nazir

    2018-01-01

    Full Text Available In this paper, a gas-fired combined cycle power plant subjected to a pre-combustion CO2 capture method has been analysed under different design conditions and different heat integration options. The power plant configuration includes the chemical looping reforming (CLR of natural gas (NG, water gas shift (WGS process, CO2 capture and compression, and a hydrogen fuelled combined cycle to produce power. The process is denoted as a CLR-CC process. One of the main parameters that affects the performance of the process is the pressure for the CLR. The process is analysed at different design pressures for the CLR, i.e., 5, 10, 15, 18, 25 and 30 bar. It is observed that the net electrical efficiency increases with an increase in the design pressure in the CLR. Secondly, the type of steam generated from the cooling of process streams also effects the net electrical efficiency of the process. Out of the five different cases including the base case presented in this study, it is observed that the net electrical efficiency of CLR-CCs can be improved to 46.5% (lower heating value of NG basis by producing high-pressure steam through heat recovery from the pre-combustion process streams and sending it to the Heat Recovery Steam Generator in the power plant.

  4. Neural network retrievals of Karenia brevis harmful algal blooms in the West Florida Shelf (Conference Presentation)

    Science.gov (United States)

    Ahmed, Samir; El-Habashi, Ahmed

    2016-10-01

    Effective detection and tracking of Karenia brevis Harmful Algal Blooms (KB HAB) that frequently plague the coasts and beaches of the West Florida Shelf (WFS) is important because of their negative impacts on ecology. They pose threats to fisheries, human health, and directly affect tourism and local economies. Detection and tracking capabilities are needed for use with the Visible Infrared Imaging Radiometer Suite (VIIRS) satellite, so that HABs monitoring capabilities, which previously relied on imagery from the Moderate Resolution Imaging Spectroradiometer Aqua, can be extended to VIIRS. Unfortunately, VIIRS, unlike its predecessor MODIS-A, does not have a 678 nm channel to detect chlorophyll fluorescence, which is used in the normalized fluorescence height (nFLH) algorithm, or in the Red Band Difference (RBD) algorithm. Both these techniques have demonstrated that the remote sensing reflectance signal from the MODIS-A fluorescence band (Rrs 678 nm) helps in effectively detecting and tracking KB HABs in the WFS. To overcome the lack of a fluorescence channel on VIIRS, the approach described here, bypasses the need for measurements at 678nm, and permits extension of KB HABs satellite monitoring to VIIRS. The essence of the approach is the application of a standard multiband neural network (NN) inversion algorithm, previously developed and reported by us, that takes VIIRS Rrs measurements at the 486, 551 and 671nm bands as inputs, and produces as output the related Inherent Optical Properties (IOPs), namely: absorption coefficients of phytoplankton (aph443) dissolved organic matter (ag) and non-algal particulates (adm) as well as the particulate backscatter coefficient, (bbp) all at 443nm. We next need to relate aph443 in the VIIRS NN retrieved image to equivalent KB HABs concentrations. To do this, we apply additional constraints, defined by (i) low backscatter manifested as a maximum Rrs551 value and (ii) a minimum [Chla] threshold (and hence an equivalent

  5. Assessment of multiple sources of anthropogenic and natural chemical inputs to a morphologically complex basin, Lake Mead, USA

    Science.gov (United States)

    Rosen, Michael R.; Van Metre, P.C.

    2010-01-01

    Lakes with complex morphologies and with different geologic and land-use characteristics in their sub-watersheds could have large differences in natural and anthropogenic chemical inputs to sub-basins in the lake. Lake Mead in southern Nevada and northern Arizona, USA, is one such lake. To assess variations in chemical histories from 1935 to 1998 for major sub-basins of Lake Mead, four sediment cores were taken from three different parts of the reservoir (two from Las Vegas Bay and one from the Overton Arm and Virgin Basin) and analyzed for major and trace elements, radionuclides, and organic compounds. As expected, anthropogenic contaminant inputs are greatest to Las Vegas Bay reflecting inputs from the Las Vegas urban area, although concentrations are low compared to sediment quality guidelines and to other USA lakes. One exception to this pattern was higher Hg in the Virgin Basin core. The Virgin Basin core is located in the main body of the lake (Colorado River channel) and is influenced by the hydrology of the Colorado River, which changed greatly with completion of Glen Canyon Dam upstream in 1963. Major and trace elements in the core show pronounced shifts in the early 1960s and, in many cases, gradually return to concentrations more typical of pre-1960s by the 1980s and 1990s, after the filling of Lake Powell. The Overton Arm is the sub-basin least effected by anthropogenic contaminant inputs but has a complex 137Cs profile with a series of large peaks and valleys over the middle of the core, possibly reflecting fallout from nuclear tests in the 1950s at the Nevada Test Site. The 137Cs profile suggests a much greater sedimentation rate during testing which we hypothesize results from greatly increased dust fall on the lake and Virgin and Muddy River watersheds. The severe drought in the southwestern USA during the 1950s might also have played a role in variations in sedimentation rate in all of the cores. ?? 2009.

  6. Nitric oxide and nitrous oxide turnover in natural and engineered microbial communities: biological pathways, chemical reactions, and novel technologies

    Science.gov (United States)

    Schreiber, Frank; Wunderlin, Pascal; Udert, Kai M.; Wells, George F.

    2012-01-01

    Nitrous oxide (N2O) is an environmentally important atmospheric trace gas because it is an effective greenhouse gas and it leads to ozone depletion through photo-chemical nitric oxide (NO) production in the stratosphere. Mitigating its steady increase in atmospheric concentration requires an understanding of the mechanisms that lead to its formation in natural and engineered microbial communities. N2O is formed biologically from the oxidation of hydroxylamine (NH2OH) or the reduction of nitrite (NO−2) to NO and further to N2O. Our review of the biological pathways for N2O production shows that apparently all organisms and pathways known to be involved in the catabolic branch of microbial N-cycle have the potential to catalyze the reduction of NO−2 to NO and the further reduction of NO to N2O, while N2O formation from NH2OH is only performed by ammonia oxidizing bacteria (AOB). In addition to biological pathways, we review important chemical reactions that can lead to NO and N2O formation due to the reactivity of NO−2, NH2OH, and nitroxyl (HNO). Moreover, biological N2O formation is highly dynamic in response to N-imbalance imposed on a system. Thus, understanding NO formation and capturing the dynamics of NO and N2O build-up are key to understand mechanisms of N2O release. Here, we discuss novel technologies that allow experiments on NO and N2O formation at high temporal resolution, namely NO and N2O microelectrodes and the dynamic analysis of the isotopic signature of N2O with quantum cascade laser absorption spectroscopy (QCLAS). In addition, we introduce other techniques that use the isotopic composition of N2O to distinguish production pathways and findings that were made with emerging molecular techniques in complex environments. Finally, we discuss how a combination of the presented tools might help to address important open questions on pathways and controls of nitrogen flow through complex microbial communities that eventually lead to N2O build

  7. Nitric oxide and nitrous oxide turnover in natural and engineered microbial communities: biological pathways, chemical reactions and novel technologies

    Directory of Open Access Journals (Sweden)

    Frank eSchreiber

    2012-10-01

    Full Text Available Nitrous oxide (N2O is an environmentally important atmospheric trace gas because it is an effective greenhouse gas and it leads to ozone depletion through photo-chemical nitric oxide (NO production in the stratosphere. Mitigating its steady increase in atmospheric concentration requires an understanding of the mechanisms that lead to its formation in natural and engineered microbial communities. N2O is formed biologically from the oxidation of hydroxylamine (NH2OH or the reduction of nitrite (NO2- to NO and further to N2O. Our review of the biological pathways for N2O production shows that apparently all organisms and pathways known to be involved in the catabolic branch of microbial N-cycle have the potential to catalyze the reduction of NO2- to NO and the further reduction of NO to N2O, while N2O formation from NH2OH is only performed by ammonia oxidizing bacteria. In addition to biological pathways, we review important chemical reactions that can lead to NO and N2O formation due to the reactivity of NO2-, NH2OH and nitroxyl (HNO. Moreover, biological N2O formation is highly dynamic in response to N-imbalance imposed on a system. Thus, understanding NO formation and capturing the dynamics of NO and N2O build-up are key to understand mechanisms of N2O release. Here, we discuss novel technologies that allow experiments on NO and N2O formation at high temporal resolution, namely NO and N2O microelectrodes and the dynamic analysis of the isotopic signature of N2O with quantum cascade laser based absorption spectroscopy. In addition, we introduce other techniques that use the isotopic composition of N2O to distinguish production pathways and findings that were made with emerging molecular techniques in complex environments. Finally, we discuss how a combination of the presented tools might help to address important open questions on pathways and controls of nitrogen flow through complex microbial communities that eventually lead to N2O build-up.

  8. Effects of Jigsaw Cooperative Learning and Animation Techniques on Students' Understanding of Chemical Bonding and Their Conceptions of the Particulate Nature of Matter

    Science.gov (United States)

    Karacop, Ataman; Doymus, Kemal

    2013-04-01

    The aim of this study was to determine the effect of jigsaw cooperative learning and computer animation techniques on academic achievements of first year university students attending classes in which the unit of chemical bonding is taught within the general chemistry course and these students' learning of the particulate nature of matter of this unit. The sample of this study consisted of 115 first-year science education students who attended the classes in which the unit of chemical bonding was taught in a university faculty of education during the 2009-2010 academic year. The data collection instruments used were the Test of Scientific Reasoning, the Purdue Spatial Visualization Test: Rotations, the Chemical Bonding Academic Achievement Test, and the Particulate Nature of Matter Test in Chemical Bonding (CbPNMT). The study was carried out in three different groups. One of the groups was randomly assigned to the jigsaw group, the second was assigned to the animation group (AG), and the third was assigned to the control group, in which the traditional teaching method was applied. The data obtained with the instruments were evaluated using descriptive statistics, one-way ANOVA, and MANCOVA. The results indicate that the teaching of chemical bonding via the animation and jigsaw techniques was more effective than the traditional teaching method in increasing academic achievement. In addition, according to findings from the CbPNMT, the students from the AG were more successful in terms of correct understanding of the particulate nature of matter.

  9. Strain-specific probiotics properties of Lactobacillus fermentum, Lactobacillus plantarum and Lactobacillus brevis isolates from Brazilian food products

    DEFF Research Database (Denmark)

    Ramos, Cintia Lacerda; Thorsen, Line; Schwan, Rosane Freitas

    2013-01-01

    A total of 234 LAB isolates from Brazilian food products were initially screened for their ability to survive at pH 2.0. Fifty one of the isolates survived and were selected. They were characterized by phenotypic methods, rep-PCR and identified using 16S rRNA gene sequencing as Lactobacillus ferm...... FFC199 showed adhesion ability to Caco-2 cells (1.6, 1.1 and 0.9 respectively) similar to the commercial probiotic, Lactobacillus rhamnosus GG (1.5. They were able to increase the transepithelial electrical resistance (TEER) of Caco-2 cells over 24 h (p ... that the probiotic characteristics were strain-specific and that the isolates L. plantarum CH3 and CH41 (cocoa) and L. brevis FFC199 (cauim) exhibited potential probiotics properties. (C) 2013 Elsevier Ltd. All rights reserved....

  10. Chemical analysis of isolated cell walls of Gram-positive bacteria and the determination of the cell wall to cell mass ratio.

    NARCIS (Netherlands)

    Wal, van der A.; Norde, W.; Bendinger, B.; Zehnder, A.J.B.; Lyklema, J.

    1997-01-01

    Cell walls of five Gram-positive bacterial strains, including four coryneforms and a Bacillus brevis strain were isolated and subsequently chemically analysed. The wall contribution to the total cell mass is calculated from a comparison of D-Lactate concentrations in hydrolysates of whole cells and

  11. Distinguishing Natural and Anthropogenic Sources of Chemical Loading on a Watershed-Scale, Mill River Watershed, Massachusetts

    Science.gov (United States)

    Rhodes, A. L.; Newton, R. M.; Pufall, A.

    2001-05-01

    The Mill River Watershed (MRW), a 125 km2 catchment of the Connecticut River, possesses heterogeneous topography, geology, and human settlement patterns suitable for distinguishing natural sources of chemical loading to rivers from anthropogenic sources. The MRW is divided into catchments by drainage patterns of dominant tributaries. Catchments are further classified into land-use zones, defined by intensity of human activity. Water chemistry in Zone I areas, where human activity is minimal to absent, serves as a baseline for assessing human impacts on water quality from within the watershed. Zone II areas are primarily affected by water removal from drinking water reservoirs on two tributaries ( ~9500 m3 per day, combined). Zone III regions receive runoff from agricultural, residential, and transportation areas. Since 1997, water samples collected from 13 sites in MRW have been analyzed for specific conductance, temperature, pH, ANC, base cations (Ca, Mg, Na, K, NH4), anions (Cl, SO4, NO3, PO4), and dissolved silica. GIS software was used to calculate percent area of different land uses that drain to each sample site. For the majority of sample sites in MRW, average concentrations of both NO3 and SO4 show a positive, linear relationship with percent area of anthropogenic land (R2> 0.91). Concentrations of Cl increase linearly with road density (R2= 0.95). However, two Zone III sites receiving additional point-source pollution show higher NO3 and SO4 concentrations than predicted by land use; concentrations reflect 20 and 50% more anthropogenic area than actually exists. Removal of drinking water from the larger reservoir also produces 20 and 30% more NO3 and SO4 than predicted by land use, showing that water removal concentrates pollution. Low-gradient, Zone III sites that receive highway runoff show elevated salt concentrations that persist throughout the year. Salt-impacted regions show a strong correlation between Na and Cl (R2 = 0.86 to 0.95). Cl typically

  12. Electromyography comparison of the effects of various footwear in the activity patterns of the peroneus longus and brevis muscles.

    Science.gov (United States)

    Roca-Dols, Andrea; Losa-Iglesias, Marta Elena; Sánchez-Gómez, Rubén; López-López, Daniel; Becerro-de-Bengoa-Vallejo, Ricardo; Calvo-Lobo, César

    2018-06-01

    Peroneus longus and brevis (PLB) disorders are commonly in people with lateral ligamentous instability, ankle pain, lateral hindfoot pain and structures of the proximal compartment of the lower legs and their muscle activity is believed to be influenced by different footwear types. The proposal of this research is to evaluate the effects of five types of footwear with respect to the barefoot condition and analyze the activity patterns of PLB muscles in healthy subjects during the gait cycle. Thirty healthy subjects were recruited in a laboratory in this cross-sectional research design. While walking, electromyography (EMG) activity was measured from PLB via surface electrodes in six experimental conditions: 1) barefoot, 2) minimalist, 3) pronated control, 4) air chamber, 5) ethyl-vinyl-acetate (EVA) and 6) boost. These data were obtained and compared. The peroneus brevis showed significant reductions in the peak amplitude of the five footwear types (minimalist, pronation control, air chamber, EVA and boost) with respect to the barefoot condition in the propulsion phase of the gait cycle during walking (P = 0.034; P footwear types with respect to the barefoot condition in the propulsion phase of the gait cycle during running (P = 0.005; P = 0.038; P = 0.019; P = 0.025; P = 0.021). The EMG activity patterns of the PLB muscles may depend on the use of different types of sport shoes such as minimalist, pronation control, air chamber, EVA and boost footwear with respect the barefoot condition in different phases of the gait cycle during walking and running. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Short-Term and Long-Term Biological Effects of Chronic Chemical Contamination on Natural Populations of a Marine Bivalve.

    Directory of Open Access Journals (Sweden)

    Marine Breitwieser

    Full Text Available Understanding the effects of chronic chemical contamination on natural populations of marine organisms is complex due to the combined effects of different types of pollutants and environmental parameters that can modulate the physiological responses to stress. Here, we present the effects of a chronic contamination in a marine bivalve by combining multiple approaches that provide information on individual and population health. We sampled variegated scallops (Mimachlamys varia at sites characterized by different contaminants and contamination levels to study the short and long-term (intergenerational responses of this species to physiological stress. We used biomarkers (SOD, MDA, GST, laccase, citrate synthase and phosphatases as indicators of oxidative stress, immune system alteration, mitochondrial respiration and general metabolism, and measured population genetic diversity at each site. In parallel, concentration of 14 trace metals and 45 organic contaminants (PAHs, PCBs, pesticides in tissues were measured. Scallops were collected outside and during their reproductive season to investigate temporal variability in contaminant and biomarker levels. Our analyses revealed that the levels of two biomarkers (Laccase-type phenoloxidase and malondialdehyde were significantly correlated with Cd concentration. Additionally, we observed significant seasonal differences for four of the five biomarkers, which is likely due to the scallop reproductive status at time of sampling. As a source of concern, a location that was identified as a reference site on the basis of inorganic contaminant levels presented the same level of some persistent organic pollutants (DDT and its metabolites than more impacted sites. Finally, potential long-term effects of heavy metal contamination were observed for variegated scallops as genetic diversity was depressed in the most polluted sites.

  14. Topological, chemical and electro-optical characteristics of riboflavin-doped artificial and natural DNA thin films

    Science.gov (United States)

    Gnapareddy, Bramaramba; Dugasani, Sreekantha Reddy; Son, Junyoung; Park, Sung Ha

    2018-02-01

    DNA is considered as a useful building bio-material, and it serves as an efficient template to align functionalized nanomaterials. Riboflavin (RF)-doped synthetic double-crossover DNA (DX-DNA) lattices and natural salmon DNA (SDNA) thin films were constructed using substrate-assisted growth and drop-casting methods, respectively, and their topological, chemical and electro-optical characteristics were evaluated. The critical doping concentrations of RF ([RF]C, approx. 5 mM) at given concentrations of DX-DNA and SDNA were obtained by observing the phase transition (from crystalline to amorphous structures) of DX-DNA and precipitation of SDNA in solution above [RF]C. [RF]C are verified by analysing the atomic force microscopy images for DX-DNA and current, absorbance and photoluminescence (PL) for SDNA. We study the physical characteristics of RF-embedded SDNA thin films, using the Fourier transform infrared spectrum to understand the interaction between the RF and DNA molecules, current to evaluate the conductance, absorption to understand the RF binding to the DNA and PL to analyse the energy transfer between the RF and DNA. The current and UV absorption band of SDNA thin films decrease up to [RF]C followed by an increase above [RF]C. By contrast, the PL intensity illustrates the reverse trend, as compared to the current and UV absorption behaviour as a function of the varying [RF]. Owing to the intense PL characteristic of RF, the DNA lattices and thin films with RF might offer immense potential to develop efficient bio-sensors and useful bio-photonic devices.

  15. The nature of alarm communication in Constrictotermes cyphergaster (Blattodea: Termitoidea: Termitidae: the integration of chemical and vibroacoustic signals

    Directory of Open Access Journals (Sweden)

    Paulo F. Cristaldo

    2015-12-01

    Full Text Available Alarm signalling is of paramount importance to communication in all social insects. In termites, vibroacoustic and chemical alarm signalling are bound to operate synergistically but have never been studied simultaneously in a single species. Here, we inspected the functional significance of both communication channels in Constrictotermes cyphergaster (Termitidae: Nasutitermitinae, confirming the hypothesis that these are not exclusive, but rather complementary processes. In natural situations, the alarm predominantly attracts soldiers, which actively search for the source of a disturbance. Laboratory testing revealed that the frontal gland of soldiers produces a rich mixture of terpenoid compounds including an alarm pheromone. Extensive testing led to identification of the alarm pheromone being composed of abundant monoterpene hydrocarbons (1S-α-pinene and myrcene, along with a minor component, (E-β-ocimene. The vibratory alarm signalling consists of vibratory movements evidenced as bursts; a series of beats produced predominantly by soldiers. Exposing termite groups to various mixtures containing the alarm pheromone (crushed soldier heads, frontal gland extracts, mixture of all monoterpenes, and the alarm pheromone mixture made of standards resulted in significantly higher activity in the tested groups and also increased intensity of the vibratory alarm communication, with the responses clearly dose-dependent. Lower doses of the pheromone provoked higher numbers of vibratory signals compared to higher doses. Higher doses induced long-term running of all termites without stops necessary to perform vibratory behaviour. Surprisingly, even crushed worker heads led to low (but significant increases in the alarm responses, suggesting that other unknown compound in the worker's head is perceived and answered by termites. Our results demonstrate the existence of different alarm levels in termites, with lower levels being communicated through

  16. Short-Term and Long-Term Biological Effects of Chronic Chemical Contamination on Natural Populations of a Marine Bivalve.

    Science.gov (United States)

    Breitwieser, Marine; Viricel, Amélia; Graber, Marianne; Murillo, Laurence; Becquet, Vanessa; Churlaud, Carine; Fruitier-Arnaudin, Ingrid; Huet, Valérie; Lacroix, Camille; Pante, Eric; Le Floch, Stéphane; Thomas-Guyon, Hélène

    2016-01-01

    Understanding the effects of chronic chemical contamination on natural populations of marine organisms is complex due to the combined effects of different types of pollutants and environmental parameters that can modulate the physiological responses to stress. Here, we present the effects of a chronic contamination in a marine bivalve by combining multiple approaches that provide information on individual and population health. We sampled variegated scallops (Mimachlamys varia) at sites characterized by different contaminants and contamination levels to study the short and long-term (intergenerational) responses of this species to physiological stress. We used biomarkers (SOD, MDA, GST, laccase, citrate synthase and phosphatases) as indicators of oxidative stress, immune system alteration, mitochondrial respiration and general metabolism, and measured population genetic diversity at each site. In parallel, concentration of 14 trace metals and 45 organic contaminants (PAHs, PCBs, pesticides) in tissues were measured. Scallops were collected outside and during their reproductive season to investigate temporal variability in contaminant and biomarker levels. Our analyses revealed that the levels of two biomarkers (Laccase-type phenoloxidase and malondialdehyde) were significantly correlated with Cd concentration. Additionally, we observed significant seasonal differences for four of the five biomarkers, which is likely due to the scallop reproductive status at time of sampling. As a source of concern, a location that was identified as a reference site on the basis of inorganic contaminant levels presented the same level of some persistent organic pollutants (DDT and its metabolites) than more impacted sites. Finally, potential long-term effects of heavy metal contamination were observed for variegated scallops as genetic diversity was depressed in the most polluted sites.

  17. A new species of small and highly abbreviated caecilian (Gymnophiona: Indotyphlidae) from the Seychelles island of Praslin, and a recharacterization of Hypogeophis brevis Boulenger, 1911.

    Science.gov (United States)

    Maddock, Simon T; Wilkinson, Mark; Nussbaum, Ronald A; Gower, David J

    2017-10-06

    A new species of indotyphlid caecilian amphibian, Hypogeophis pti sp. nov., is described based on a series of specimens from the Seychelles island of Praslin. The type series was collected in 2013 and 2014, and a referred specimen previously identified as H. brevis Boulenger, 1911 was collected from an unspecified Seychelles locality in 1957. The new species most closely resembles the Seychelles endemic Hypogeophis brevis in being short (maximum known total length in life ca. 120 mm) and long snouted, but differs by having a less anteriorly positioned tentacular aperture and fewer primary annuli and vertebrae. In having only 67-69 vertebrae, H. pti sp. nov. is the most abbreviated extant species of caecilian reported to date.

  18. Procedures of amino acid sequencing of peptides in natural proteins collection of knowledge and intelligence for construction of reliable chemical inference system

    OpenAIRE

    Kudo, Yoshihiro; Kanaya, Shigehiko

    1994-01-01

    In order to establish a reliable chemical inference system on amino acid sequencing of natural peptides, as various kinds of relevant knowledge and intelligence as possible are collected. Topics are on didemnins, dolastatin 3, TL-119 and/or A-3302-B, mycosubtilin, patellamide A, duramycin (and cinnamycin), bottoromycin A 2, A19009, galantin I, vancomycin, stenothricin, calf speleen profilin, neocarzinostatin, pancreatic spasmolytic polypeptide, cerebratulus toxin B-IV, RNAase U 2, ferredoxin ...

  19. Changes in properties of DNA caused by gamma and ultraviolet radiation. Dependence of conformational changes on the chemical nature of the damage

    Energy Technology Data Exchange (ETDEWEB)

    Vorlickova, M; Palacek, E [Ceskoslovenska Akademie Ved, Brno. Biofysikalni Ustav

    1978-02-16

    Changes in the pulse-polarographic behaviour and circular dichroism spectra of DNA were investigated after gamma and ultraviolet irradiations and after degradation by DNAase I. It was found that moderate doses of radiation cause local conformational changes in the double helix which are dependent on the chemical nature of the damage. Only the accumulation of structural changes after high doses of the radiations or after extensive enzymic treatment may cause formation of single-standed regions in DNA.

  20. Enhanced Production of Gamma-Aminobutyric Acid by Optimizing Culture Conditions of Lactobacillus brevis HYE1 Isolated from Kimchi, a Korean Fermented Food.

    Science.gov (United States)

    Lim, Hee Seon; Cha, In-Tae; Roh, Seong Woon; Shin, Hae-Hun; Seo, Myung-Ji

    2017-03-28

    This study evaluated the effects of culture conditions, including carbon and nitrogen sources, L-monosodium glutamate (MSG), and initial pH, on gamma-aminobutyric acid (GABA) production by Lactobacillus brevis HYE1 isolated from kimchi, a Korean traditional fermented food. L. brevis HYE1 was screened by the production analysis of GABA and genetic analysis of the glutamate decarboxylase gene, resulting in 14.64 mM GABA after 48 h of cultivation in MRS medium containing 1% (w/v) MSG. In order to increase GABA production by L. brevis HYE1, the effects of carbon and nitrogen sources on GABA production were preliminarily investigated via one-factor-at-a-time optimization strategy. As the results, 2% maltose and 3% tryptone were determined to produce 17.93 mM GABA in modified MRS medium with 1% (w/v) MSG. In addition, the optimal MSG concentration and initial pH were determined to be 1% and 5.0, respectively, resulting in production of 18.97 mM GABA. Thereafter, response surface methodology (RSM) was applied to determine the optimal conditions of the above four factors. The results indicate that pH was the most significant factor for GABA production. The optimal culture conditions for maximum GABA production were also determined to be 2.14% (w/v) maltose, 4.01% (w/v) tryptone, 2.38% (w/v) MSG, and an initial pH of 4.74. In these conditions, GABA production by L. brevis HYE1 was predicted to be 21.44 mM using the RSM model. The experiment was performed under these optimized conditions, resulting in GABA production of 18.76 mM. These results show that the predicted and experimental values of GABA production are in good agreement.

  1. Cell surface acid-base properties of Escherichia coli and Bacillus brevis and variation as a function of growth phase, nitrogen source and C:N ratio.

    Science.gov (United States)

    Hong, Yongsuk; Brown, Derick G

    2006-07-01

    Potentiometric titration has been conducted to systematically examine the acid-base properties of the cell surfaces of Escherichia coli K-12 and Bacillus brevis as a function of growth phase, nitrogen source (ammonium or nitrate), and carbon to nitrogen (C:N) ratio of the growth substrate. The two bacterial species revealed four distinct proton binding sites, with pK(a) values in the range of 3.08-4.05 (pK(1)), 4.62-5.57 (pK(2)), 6.47-7.30 (pK(3)), and 9.68-10.89 (pK(4)) corresponding to phosphoric/carboxylic, carboxylic, phosphoric, and hydroxyl/amine groups, respectively. Two general observations in the data are that for B. brevis the first site concentration (N(1)), corresponding to phosphoric/carboxylic groups (pK(1)), varied as a function of nitrogen source, while for E. coli the fourth site concentration (N(4)), corresponding to hydroxyl/amine groups (pK(4)), varied as a function of C:N ratio. Correspondingly, it was found that N(1) was the highest of the four site concentrations for B. brevis and N(4) was the highest for E. coli. The concentrations of the remaining sites showed little variation. Finally, comparison between the titration data and a number of cell surface compositional studies in the literature indicates one distinct difference between the two bacteria is that pK(4) of the Gram-negative E. coli can be attributed to hydroxyl groups while that of the Gram-positive B. brevis can be attributed to amine groups.

  2. The Prevalence and Role of Low Lying Peroneus Brevis Muscle Belly in Patients with Peroneal Tendon Pathologies: A Potential Source for Tendon Subluxation

    OpenAIRE

    Mirmiran, Roya; Squire, Chad; Wassell, Daniel

    2015-01-01

    A low lying peroneus brevis muscle belly is a rare anomaly. There are few published studies that support presence of this anomaly as an etiology for peroneal tendon tear. However, the association between a low lying peroneus muscle belly (LLMB) and tendon subluxation is not well explored. In this retrospective study, the magnetic resonance imaging (MRI) and intraoperative findings of 50 consecutive patients undergoing a primary peroneal tendon surgery, in a five year period, were assessed. Th...

  3. Implications of global climate change for the assessment and management of human health risks of chemicals in the natural environment.

    Science.gov (United States)

    Balbus, John M; Boxall, Alistair B A; Fenske, Richard A; McKone, Thomas E; Zeise, Lauren

    2013-01-01

    Global climate change (GCC) is likely to alter the degree of human exposure to pollutants and the response of human populations to these exposures, meaning that risks of pollutants could change in the future. The present study, therefore, explores how GCC might affect the different steps in the pathway from a chemical source in the environment through to impacts on human health and evaluates the implications for existing risk-assessment and management practices. In certain parts of the world, GCC is predicted to increase the level of exposure of many environmental pollutants due to direct and indirect effects on the use patterns and transport and fate of chemicals. Changes in human behavior will also affect how humans come into contact with contaminated air, water, and food. Dietary changes, psychosocial stress, and coexposure to stressors such as high temperatures are likely to increase the vulnerability of humans to chemicals. These changes are likely to have significant implications for current practices for chemical assessment. Assumptions used in current exposure-assessment models may no longer apply, and existing monitoring methods may not be robust enough to detect adverse episodic changes in exposures. Organizations responsible for the assessment and management of health risks of chemicals therefore need to be more proactive and consider the implications of GCC for their procedures and processes. Copyright © 2012 SETAC.

  4. Using a Total Environment Framework (Built, Natural, Social Environments) to Assess Life-long Health Effects of Chemical Exposures

    Science.gov (United States)

    EPAseeks applications for research on how pollution affects human health in the context of the total environment – built, natural, and social environments interacting together with inherent characteristics and interactions.

  5. Mimicking natural cell environments: design, fabrication and application of bio-chemical gradients on polymeric biomaterial substrates

    NARCIS (Netherlands)

    Benetti, Edmondo Maria; Klein Gunnewiek, Michel; van Blitterswijk, Clemens; Vancso, Gyula J.; Moroni, Lorenzo

    2016-01-01

    Gradients of biomolecules on synthetic, solid substrates can efficiently mimic the natural, graded variation of properties of the extracellular matrix (ECM). Such gradients represent accessible study platforms for the understanding of cellular activities, and they also provide functional supports

  6. COMPARISON OF SORPTION ENERGTICS FOR HYDROPHOBIC ORGANIC CHEMICALS BY SYNTHETIC AND NATURAL SORBENTS FROM METHANOL/WATER SOLVENT MIXTURES

    Science.gov (United States)

    Reversed-phase liquid chromatography (RPLC) was used to investigate the thermodynamics and mechanisms of hydrophobic organic chemical (HOC) retention from methanol/water solvent mixtures. The enthalpy-entropy compensation model was used to infer that the hydro- phobic sorptive me...

  7. Students' Understanding of the Nature of Matter and Chemical Reactions--A Longitudinal Study of Conceptual Restructuring

    Science.gov (United States)

    Øyehaug, Anne Bergliot; Holt, Anne

    2013-01-01

    This longitudinal study aims to provide greater insight into how students' understanding of matter and chemical reactions develops over time and how their knowledge structures are restructured. Four case-study students in a Norwegian primary school were followed for two years from age 10-11 to age 12-13. Researchers were responsible for…

  8. Protein structure similarity clustering (PSSC) and natural product structure as inspiration sources for drug development and chemical genomics

    NARCIS (Netherlands)

    Dekker, Frank J; Koch, Marcus A; Waldmann, Herbert; Dekker, Frans

    Finding small molecules that modulate protein function is of primary importance in drug development and in the emerging field of chemical genomics. To facilitate the identification of such molecules, we developed a novel strategy making use of structural conservatism found in protein domain

  9. Incidental magnetic resonance imaging signal changes in the extensor carpi radialis brevis origin are more common with age.

    Science.gov (United States)

    van Leeuwen, Wouter F; Janssen, Stein J; Ring, David; Chen, Neal

    2016-07-01

    Patients with enthesopathy of the extensor carpi radialis brevis (ECRB) demonstrate signal changes on magnetic resonance imaging (MRI). It is likely that these MRI changes persist for many years or may be permanent, regardless of symptoms, and represent an estimation of disease prevalence. We tested the hypothesis that the prevalence of incidental signal changes in the ECRB origin increases with age. We searched MRI reports of 3374 patients who underwent an MRI scan, including the elbow, for signal changes in the ECRB origin. Medical records were reviewed for symptoms consistent with ECRB enthesopathy. Prevalences of incidental and symptomatic signal changes were calculated and stratified by age. We used multivariate logistic regression analysis to test whether age, sex, and race were independently associated with ECRB enthesopathy and calculated odds ratios. Signal changes in ECRB origin were identified on MRI scans of 369 of 3374 patients (11%) without a clinical suspicion of tennis elbow. The prevalence increased from 5.7% in patients aged between 18 and 30 years up to 16% in patients aged 71 years and older. Older age (odds ratio, 1.04; P elbow MRI scans. Increased MRI signal in the ECRB origin is common in symptomatic and in asymptomatic elbows. Our findings support the concept that ECRB enthesopathy is a highly prevalent, self-limited process that seems to affect a minimum of 1 in approximately every 7 people. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  10. The serotonin receptor mediates changes in autonomic neurotransmission and gastrointestinal transit induced by heat-killed Lactobacillus brevis SBC8803.

    Science.gov (United States)

    Horii, Y; Nakakita, Y; Misonou, Y; Nakamura, T; Nagai, K

    2015-01-01

    Lactobacilli exhibit several health benefits in mammals, including humans. Our previous reports established that heat-killed Lactobacillus brevis SBC8803 (SBC8803) increased both efferent gastric vagal nerve activity and afferent intestinal vagal nerve activity in rats. We speculated that this strain could be useful for the treatment of gastrointestinal (GI) disorders. In this study, we examined the effects of SBC8803 on peristalsis and the activity of the efferent celiac vagal nerve innervating the intestine in rats. First, we examined the effects of intraduodenal (ID) administration of SBC8803 on efferent celiac vagal nerve activity (efferent CVNA) in urethane-anesthetised rats using electrophysiological studies. The effects of intravenous injection of the serotonin 5-HT3 receptor antagonist granisetron on changes in efferent CVNA due to ID administration of SBC8803 were also investigated. Finally, the effects of oral gavage of SBC8803 on GI transit were analysed using the charcoal propulsion method in conscious rats treated with or without granisetron. ID administration of SBC8803 increased efferent CVNA. Pretreatment with granisetron eliminated SBC8803-dependent changes in efferent CVNA. Furthermore, oral gavage of SBC8803 significantly accelerated GI transit, while pretreatment with granisetron inhibited GI transit. Our findings suggested that SBC8803 increased efferent CVNA and GI transit of charcoal meal via 5-HT3 receptors. Moreover, SBC8803 enhanced the activity of efferent vagal nerve innervating the intestine and promoted peristalsis via 5-HT3 receptors.

  11. Microbial production of mannitol by Lactobacillus brevis 3-A5 from concentrated extract of Jerusalem artichoke tubers.

    Science.gov (United States)

    Cao, Hailong; Yue, Min; Liu, Gang; Du, Yuguang; Yin, Heng

    2018-05-01

    In the present study, the conversion of the extract of Jerusalem artichoke tubers for mannitol production by Lactobacillus brevis 3-A5 was investigated. When the bacterium utilized enzymatic hydrolysates of Jerusalem artichoke extract as the main substrates in batch fermentation, the significant decrease in mannitol productivity was observed when the initial concentration of reducing sugar increased. Then, a strategy of continuous fed-batch fermentation was adopted for improving mannitol production with enzymatic hydrolysates of Jerusalem artichoke extract as main substrates. Although the concentration of mannitol could reach 199.86 g/L at the end of the fermentation, the productivity for the overall process of the fermentation was only 1.67 g/L/H. To improve the mannitol productivity with both higher yield and concentration, the simultaneous enzymatic saccharification and fermentation (SSF) was studied. In SSF, the mannitol production reached 176.50 g/L in 28 H with a productivity of 6.30 g/L/H and a yield of 0.68 g/g total sugar. Our study provides a cost-effective and eco-friendly method for mannitol production from a cheap biomass. © 2017 International Union of Biochemistry and Molecular Biology, Inc.

  12. [Statistical (Poisson) motor unit number estimation. Methodological aspects and normal results in the extensor digitorum brevis muscle of healthy subjects].

    Science.gov (United States)

    Murga Oporto, L; Menéndez-de León, C; Bauzano Poley, E; Núñez-Castaín, M J

    Among the differents techniques for motor unit number estimation (MUNE) there is the statistical one (Poisson), in which the activation of motor units is carried out by electrical stimulation and the estimation performed by means of a statistical analysis based on the Poisson s distribution. The study was undertaken in order to realize an approximation to the MUNE Poisson technique showing a coprehensible view of its methodology and also to obtain normal results in the extensor digitorum brevis muscle (EDB) from a healthy population. One hundred fourteen normal volunteers with age ranging from 10 to 88 years were studied using the MUNE software contained in a Viking IV system. The normal subjects were divided into two age groups (10 59 and 60 88 years). The EDB MUNE from all them was 184 49. Both, the MUNE and the amplitude of the compound muscle action potential (CMAP) were significantly lower in the older age group (page than CMAP amplitude ( 0.5002 and 0.4142, respectively pphisiology of the motor unit. The value of MUNE correlates better with the neuromuscular aging process than CMAP amplitude does.

  13. PEMBERIAN PROBIOTIK LACTOBACILLUS BREVIS DAN PREBIOTIK OLIGOSAKARIDA PADA BENIH PATIN SIAM (Pangasionodon hypophthalmus YANG DIINFEKSI Aeromonas hydrophila

    Directory of Open Access Journals (Sweden)

    Yuke Eliyani

    2013-08-01

    Lactobacillus brevis, prebiotik oligosakarida dan sinbiotiknya terhadap jumlah bakteri Lactobacillus sp. dan total bakteri dalam usus, total eritrosit, total leukosit, diferensial leukosit, aktivitas fagositik, sintasan, tingkat pertumbuhan, serta FCR benih ikan patin siam yang diinfeksi Aeromonas hydrophila. Hasil uji karakteristik menunjukkan bahwa jenis probiotik dan patogen adalah Lactobacillus sp. dan Aeromonas hydrophila. Pada uji in vivo digunakan lima perlakuan yang terdiri atas K(+, K(-, probiotik (pro, prebiotik (pre serta sinbiotik (sin. Bakteri Lactobacillus sp. ditemukan di usus pada perlakuan probiotik dan sinbiotik dengan kisaran jumlah sekitar 101 sampai 106 (CFU/g. Total eritrosit, total leukosit, aktivitas fagositik berbeda nyata (P<0,05 dengan kontrol pada beberapa waktu pengamatan. Tingkat sintasan terendah diperoleh pada perlakuan K(+ sebesar 43,33±11,55; sedangkan empat perlakuan lainnya memperoleh nilai 100%. Tingkat pertumbuhan harian berbeda nyata antar perlakuan, nilai terbaik dicapai pada perlakuan pemberian sinbiotik sebesar 3,370±0,14. Nilai FCR perlakuan probiotik, prebiotik dan sinbiotik menunjukkan beda nyata dengan kontrol. Perlakuan sin, pre, pro memberikan nilai yang lebih baik pada total eritrosit, total leukosit, aktivitas fagositik, sintasan, pertumbuhan, dan FCR dibandingkan kontrol.

  14. Binding assays for the quantitative detection of P. brevis polyether neurotoxins in biological samples and antibodies as therapeutic aids for polyether marine intoxication. Annual report, 1 December 1987-30 November 1988

    Energy Technology Data Exchange (ETDEWEB)

    Baden, D.G.

    1988-12-15

    The polyether lipid-soluble toxins isolated from the marine dinoflagellate Ptychodiscus brevis (formerly Gymnodinium breve) can be detected using two separate types of specific binding reaction. Using tritiated PbTx-3 as a specific probe for binding to voltage-dependent sodium channels in rat brain synaptosomes or to specific polyclonal antibodies, binding equilibria and displacement by unlabeled brevetoxins were compared. Labeled toxin can be displaced in a competitive manner by any of the other 5 naturally-occurring toxins; the quantitative displacement ability of each appears to reflect individual potency in fish bioassay. A comparison of ED50 in Radioimmunoassay and ED50 in synaptosome binding assay indicates that the former assay is useful for detection of toxins which possess the structural backbone of PbTx-3, the immunizing hapten. Thus, the two assays have quantitative applicability; the sodium channel with respect to potency and the antibodies with respect to structure. Microtiter plate assays utilizing each specific brevetoxin binding component and enzyme-linked toxin hapten have been successful and indicate a general applicability of colorimetric prototypes. There, is however, considerable manipulation required to decrease non-specific binding of the hydrophobic toxin-enzyme complex to the plates. Preliminary studies aimed at producing monoclonal antibodies have been explored using brevetoxins linked to keyhole limpet hemocyanin.

  15. Effect of oxidation on the chemical nature and distribution of low-temperature pyrolysis products from bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E.; MacPhee, J.A.; Vancea, L.; Ciavaglia, L.A.; Nandi, B.N.

    1983-04-01

    Two bituminous coals, a high volatile Eastern Canadian and a medium volatile Western Canadian, were used to investigate the effect of oxidation on yields and chemical composition of gases, liquids and chars produced during coal pyrolysis. Pyrolysis experiments were performed at 500 C using the Fischer assay method. Mild oxidation of coals resulted in a decrease of liquid hydrocarbon yields. Further coal oxidation increased the proportion of aromatic carbon in liquid products as determined by N.M.R. and also increased the content of oxygen in liquid products. The content of oxygen in chars was markedly lower than in corresponding coals. An attempt is made to explain reactions occurring during oxidation and subsequent pyrolysis of coal on the basis of differences in chemical composition of gases, liquids and chars. (19 refs.)

  16. Effect of oxidation on the chemical nature and distribution of low-temperature pyrolysis products from bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E.; Ciavaglia, L.A.; MacPhee, J.A.; Nandi, B.N.; Vancea, L.

    1983-04-01

    Two bituminous coals, a high volatile Eastern Canadian and a medium volatile Western Canadian, were used to investigate the effect of oxidation on yields and chemical composition of gases, liquids and chars produced during coal pyrolysis. Pyrolysis experiments were performed at 500/sup 0/C using the Fischer assay method. Mild oxidation of coals resulted in a decrease of liquid hydrocarbon yields. Further coal oxidation increased the proportion of aromatic carbon in liquid products as determined by n.m.r., and also increased the content of oxygen in liquid products. The content of oxygen in chars was markedly lower than in corresponding coals. An attempt is made to explain reactions occurring during oxidation and subsequent pyrolysis of coal on the basis of differences in chemical composition of gases, liquids and chars.

  17. Surface chemical characteristics of coal fly ash particles after interaction with seawater under natural deep sea conditions

    International Nuclear Information System (INIS)

    Brami, Y.; Shemesh, A.; Cohen, H.; Herut, B.

    1999-01-01

    The surface chemical characteristics of coal fly ash (CFA) before and after interaction with Mediterranean deep seawater was studied by X-ray photoelectron spectroscopy (XPS). Significantly lower values of Si, Ca, and S and higher values of Mg and Cl were found in the retrieved CFA as compared to fresh CFA. It is suggested that hydrolysis of the oxide matrixes results in an alkaline environment which rapidly leads to several chemical reactions. The two most important are (a) dissolution of the amorphous silicate and the calcium phases and (b) precipitation of Mg(OH) 2 -brucite. A depth profile of the retrieved CFA was measured by both line-shape analysis of the XPS spectra and by consecutive cycle of sputtering. The thickness of the brucite layer is estimated to be 1.3 nm

  18. Health and Natural Resources: The Extraction of Useful Chemicals from Plants and their Impact on Socio-Economic Development

    International Nuclear Information System (INIS)

    Munavu, R.M.

    2006-01-01

    Poverty reduction strategies in developing countries are based on the need to develop and improve the quality of life of people. The successful strategies link wealth creating activities of adding value to local resources with employment creation. These strategies lead to increased capacity to produce needed consumer goods such as food, fuel, construction materials, textiles and pharmaceuticals starting from local resources. Most value-adding transformations of materials to consumer goods use chemicals conversion processes

  19. Chemically exfoliated Mo S2 layers: Spectroscopic evidence for the semiconducting nature of the dominant trigonal metastable phase

    Science.gov (United States)

    Pal, Banabir; Singh, Anjali; Sharada, G.; Mahale, Pratibha; Kumar, Abhinav; Thirupathaiah, S.; Sezen, H.; Amati, M.; Gregoratti, Luca; Waghmare, Umesh V.; Sarma, D. D.

    2017-11-01

    A metastable trigonal phase, existing only as small patches on a chemically exfoliated few-layered, thermodynamically stable 1 H phase of Mo S2 , is believed to critically influence the properties of Mo S2 -based devices. The electronic structure of this metastable phase is little understood in the absence of a direct experimental investigation of its electronic properties, complicated further by conflicting claims from theoretical investigations. We address this issue by investigating the electronic structure of this minority phase in chemically exfoliated Mo S2 few-layered systems by enhancing its contributions with the use of highly spatially resolved (≤120 nm resolution) photoemission spectroscopy and Raman spectroscopy in conjunction with state-of-the-art electronic structure calculations. Based on these results, we establish that the ground state of this phase, arrived at by the chemical exfoliation of Mo S2 using the usual Li intercalation technique, is a small gap (˜90 ±40 meV ) semiconductor in contrast to most claims in the literature; we also identify the specific trigonal structure it has among many suggested ones.

  20. Heteronuclear three-dimensional NMR spectroscopy. Natural abundance 13C chemical shift editing of 1H-1H COSY spectra

    International Nuclear Information System (INIS)

    Fesik, S.W.; Gampe, R.T. Jr.; Zuiderweg, E.R.P.

    1989-01-01

    It has been demonstrated that heteronuclear 3D NMR spectroscopy can be effectively applied to small molecules with 13 C at natural abundance. A 78mM solution of the aminoglycoside, kanamycin A was used for this experiment. The heteronuclear 3D NMR spectroscopy is shown to be a useful method for resolving spectral overlap in all frequency domains. 10 refs., 2 figs

  1. Studies on the chemical resistance and mechanical properties of natural polyalthia cerasoides woven fabric/glass hybridized epoxy composites

    CSIR Research Space (South Africa)

    Jayaramudu, J

    2015-01-01

    Full Text Available In the present work, natural Polyalthiacerasoide woven fabrics were extracted from the bark of the tree and using these woven fabrics/glass fibre as reinforcements and epoxy as matrix the hybrid composites were prepared by the hand lay-up technique...

  2. Leaching of biomass from semi-natural grasslands – Effects on chemical composition and ash high-temperature behaviour

    International Nuclear Information System (INIS)

    Tonn, Bettina; Thumm, Ulrich; Lewandowski, Iris; Claupein, Wilhelm

    2012-01-01

    Combustion of biodiversity-rich semi-natural grassland biomass no longer needed for forage allows nature conservation to be combined with bioenergy production. Natural leaching by rainfall during the period between biomass harvest and collection can reduce the content of elements detrimental for the combustion of grassland biomass. This study assesses the influence of biomass characteristics on leaching efficiency and the potential effects of leaching on ash melting behaviour and elemental release. Grassland biomass harvested from five sites at two harvest dates was leached at two intensities. Low-temperature ash was heated to 700, 800, 900 and 1000 °C respectively and classified into four ash fusion classes. Ash mass loss was determined as a measure of high-temperature elemental release. Weather data were used to calculate the frequency of weather conditions favourable to on-field leaching. K and Cl were leached most strongly and were reduced by 30 and 45% respectively by a leaching treatment corresponding to 30–40 mm of rain. The effects of site and harvest date on leaching efficiency were significant but small. Ash melting behaviour and elemental release between 700 and 900 °C were favourably influenced by leaching. The K/(Ca + Mg) and Si/ash ratios were related to increased ash melting. In this respect, semi-natural grassland biomass differs from other, less Ca-rich, herbaceous biofuels. Even if suitable weather conditions are not occurring frequently at the study sites, on-field leaching can offer an additional low-cost, on-farm strategy option for farmers and nature conservation agencies to improve biomass quality of nature conservation grasslands for combustion. -- Graphical abstract: Highlights: ► Combustion of biomass from biodiversity-rich nature conservation grassland. ► Leaching by rain during the field period reduces K and Cl concentrations. ► Increasing K/(Ca + Mg) and decreasing (K + Ca + Mg)/ash ratios increase ash melting. ► Leaching

  3. Expanding the chemical diversity of natural esters by engineering a polyketide-derived pathway into Escherichia coli.

    Science.gov (United States)

    Menendez-Bravo, Simón; Comba, Santiago; Sabatini, Martín; Arabolaza, Ana; Gramajo, Hugo

    2014-07-01

    Microbial fatty acid (FA)-derived molecules have emerged as promising alternatives to petroleum-based chemicals for reducing dependence on fossil hydrocarbons. However, native FA biosynthetic pathways often yield limited structural diversity, and therefore restricted physicochemical properties, of the end products by providing only a limited variety of usually linear hydrocarbons. Here we have engineered into Escherichia coli a mycocerosic polyketide synthase-based biosynthetic pathway from Mycobacterium tuberculosis and redefined its biological role towards the production of multi-methyl-branched-esters (MBEs) with novel chemical structures. Expression of FadD28, Mas and PapA5 enzymes enabled the biosynthesis of multi-methyl-branched-FA and their further esterification to an alcohol. The high substrate tolerance of these enzymes towards different FA and alcohol moieties resulted in the biosynthesis of a broad range of MBE. Further metabolic engineering of the MBE producer strain coupled this system to long-chain-alcohol biosynthetic pathways resulting in de novo production of branched wax esters following addition of only propionate. Copyright © 2014 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  4. Chemical constituents of fine particulate air pollution and pulmonary function in healthy adults: The Healthy Volunteer Natural Relocation study

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Shaowei; Deng, Furong; Hao, Yu [Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing (China); Shima, Masayuki [Department of Public Health, Hyogo College of Medicine, Hyogo (Japan); Wang, Xin; Zheng, Chanjuan; Wei, Hongying; Lv, Haibo; Lu, Xiuling; Huang, Jing; Qin, Yu [Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing (China); Guo, Xinbiao, E-mail: guoxb@bjmu.edu.cn [Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing (China)

    2013-09-15

    Highlights: • Study subjects relocated between areas with different air pollution contents. • PM{sub 2.5} showed the most consistent inverse associations with pulmonary function. • Cu, Cd, As and Sn were consistently associated with reduced pulmonary function. • Carbonaceous fractions, SO{sub 4}{sup 2−} and Sb were also associated with pulmonary function. • Sources may include traffic, industry, coal burning, and long range transported dust. -- Abstract: The study examined the associations of 32 chemical constituents of particulate matter with an aerodynamic diameter ≤2.5 μm (PM{sub 2.5}) with pulmonary function in a panel of 21 college students. Study subjects relocated from a suburban area to an urban area with changing ambient air pollution levels and contents in Beijing, China, and provided daily morning/evening peak expiratory flow (PEF) and forced expiratory volume in 1 s (FEV{sub 1}) measurements over 6 months in three study periods. There were significant reductions in evening PEF and morning/evening FEV{sub 1} associated with various air pollutants and PM{sub 2.5} constituents. Four PM{sub 2.5} constituents (copper, cadmium, arsenic and stannum) were found to be most consistently associated with the reductions in these pulmonary function measures. These findings provide clues for the respiratory effects of specific particulate chemical constituents in the context of urban air pollution.

  5. The nature of chemical bonding in actinide and lanthanide ferrocyanides determined by X-ray absorption spectroscopy and density functional theory.

    Science.gov (United States)

    Dumas, Thomas; Guillaumont, Dominique; Fillaux, Clara; Scheinost, Andreas; Moisy, Philippe; Petit, Sébastien; Shuh, David K; Tyliszczak, Tolek; Den Auwer, Christophe

    2016-01-28

    The electronic properties of actinide cations are of fundamental interest to describe intramolecular interactions and chemical bonding in the context of nuclear waste reprocessing or direct storage. The 5f and 6d orbitals are the first partially or totally vacant states in these elements, and the nature of the actinide ligand bonds is related to their ability to overlap with ligand orbitals. Because of its chemical and orbital selectivities, X-ray absorption spectroscopy (XAS) is an effective probe of actinide species frontier orbitals and for understanding actinide cation reactivity toward chelating ligands. The soft X-ray probes of the light elements provide better resolution than actinide L3-edges to obtain electronic information from the ligand. Thus coupling simulations to experimental soft X-ray spectral measurements and complementary quantum chemical calculations yields quantitative information on chemical bonding. In this study, soft X-ray XAS at the K-edges of C and N, and the L2,3-edges of Fe was used to investigate the electronic structures of the well-known ferrocyanide complexes K4Fe(II)(CN)6, thorium hexacyanoferrate Th(IV)Fe(II)(CN)6, and neodymium hexacyanoferrate KNd(III)Fe(II)(CN)6. The soft X-ray spectra were simulated based on quantum chemical calculations. Our results highlight the orbital overlapping effects and atomic effective charges in the Fe(II)(CN)6 building block. In addition to providing a detailed description of the electronic structure of the ferrocyanide complex (K4Fe(II)(CN)6), the results strongly contribute to confirming the actinide 5f and 6d orbital oddity in comparison to lanthanide 4f and 5d.

  6. Natural weathering in dry disposed ash dump: Insight from chemical, mineralogical and geochemical analysis of fresh and unsaturated drilled cores.

    Science.gov (United States)

    Akinyemi, S A; Akinlua, A; Gitari, W M; Khuse, N; Eze, P; Akinyeye, R O; Petrik, L F

    2012-07-15

    Some existing alternative applications of coal fly ash such as cement manufacturing; road construction; landfill; and concrete and waste stabilisation use fresh ash directly collected from coal-fired power generating stations. Thus, if the rate of usage continues, the demand for fresh ash for various applications will exceed supply and use of weathered dry disposed ash will become necessary alternative. As a result it's imperative to understand the chemistry and pH behaviour of some metals inherent in dry disposed fly ash. The bulk chemical composition as determined by XRF analysis showed that SiO2, Al2O3 and Fe2O3 were the major oxides in fresh ash and unsaturated weathered ashes. The unsaturated weathered ashes are relatively depleted in CaO, Fe2O3, TiO2, SiO2, Na2O and P2O5 due to dissolution and hydrolysis caused by chemical interaction with ingressing CO2 from the atmosphere and infiltrating rain water. Observed accumulations of Fe2O3, TiO2, CaO, K2O, Na2O and SO3 and Zn, Zr, Sr, Pb, Ni, Cr and Co in the lower layers indicate progressive downward movement through the ash dump though at a slow rate. The bulk mineralogy of unsaturated weathered dry disposed ash, as determined by XRD analysis, revealed quartz and mullite as the major crystalline phases; while anorthite, hematite, enstatite, lime, calcite, and mica were present as minor mineral phases. Pore water chemistry revealed a low concentration of readily soluble metals in unsaturated weathered ashes in comparison with fresh ash, which shows high leachability. This suggests that over time the precipitation of transient minor secondary mineral phases; such as calcite and mica might retard residual metal release from unsaturated weathered ash. Chloride and sulphate species of the water soluble extracts of weathered ash are at equilibrium with Na+ and K+; these demonstrate progressive leaching over time and become supersaturated at the base of unsaturated weathered ash. This suggests that the ash dump does not

  7. The calculation of radiation fields of chemical contamination of nature with the use of a digital model

    International Nuclear Information System (INIS)

    Mehtiev, D.S.; Sultanov, D.A.; Azizov, B.M.

    2008-01-01

    Danger of contamination of the environment by convection of air and fluid transport in porous media arise while disposing of waste radioactive isotopes and chemical industry waste in underground deep-seated horizons. As a result there is eventually observed the formation of radioactive fields of local character. A lot of methods using for defining of radioactive fields of objects of the similar type, basically are based on the registration particles and quantum, emitted by nuclear of the corresponding elements in their radioactive decay. This is especially important for objects intended for placement in the mass of low permeable rocks, such as rock type. On the base of complex using of modern information basis created the model of induced radiation field of environment

  8. Operation of the NETL Chemical Looping Reactor with Natural Gas and a Novel Copper-Iron Material

    Energy Technology Data Exchange (ETDEWEB)

    Bayham, Sanuel [National Energy Technology Lab. (NETL), Morgantown, WV (United States); Straub, Doug [National Energy Technology Lab. (NETL), Morgantown, WV (United States); Weber, Justin [National Energy Technology Lab. (NETL), Morgantown, WV (United States)

    2017-02-01

    As part of the U.S. Department of Energy’s Advanced Combustion Program, the National Energy Technology Laboratory’s Research and Innovation Center (NETL R&IC) is investigating the feasibility of a novel combustion concept in which the GHG emissions can be significantly reduced. This concept involves burning fuel and air without mixing these two reactants. If this concept is technically feasible, then CO2 emissions can be significantly reduced at a much lower cost than more conventional approaches. This indirect combustion concept has been called Chemical Looping Combustion (CLC) because an intermediate material (i.e., a metaloxide) is continuously cycled to oxidize the fuel. This CLC concept is the focus of this research and will be described in more detail in the following sections.

  9. Sequential chemical treatment of radium species in TENORM waste sludge produced from oil and natural gas production

    International Nuclear Information System (INIS)

    El Afifi, E.M.; Awwad, N.S.; Hilal, M.A.

    2009-01-01

    This paper is dedicated to the treatment of sludge occurring in frame of the Egyptian produced from oil and gas production. The activity levels of three radium isotopes: Ra-226 (of U-series), Ra-228 and Ra-224 (of Th-series) in the solid TENORM waste (sludge) were first evaluated and followed by a sequential treatment for all radium species (fractions) presented in TENORM. The sequential treatment was carried out based on two approaches 'A' and 'B' using different chemical solutions. The results obtained indicate that the activity levels of all radium isotopes (Ra-226, Ra-228 and Ra-224) of the environmental interest in the TENORM waste sludge were elevated with regard to exemption levels established by IAEA [International Atomic Energy Agency (IAEA), International basic safety standards for the protection against ionizing radiation and for the safety of radiation sources. GOV/2715/Vienna, 1994]. Each approach of the sequential treatment was performed through four steps using different chemical solutions to reduce the activity concentration of radium in a large extent. Most of the leached radium was found as an oxidizable Ra species. The actual removal % leached using approach B was relatively efficient compared to A. It is observed that the actual removal percentages (%) of Ra-226, Ra-228 and Ra-224 using approach A are 78 ± 2.8, 64.8 ± 4.1 and 76.4 ± 5.2%, respectively. Whereas in approach A, the overall removal % of Ra-226, Ra-228 and Ra-228 was increased to ∼91 ± 3.5, 87 ± 4.1 and 90 ± 6.2%, respectively

  10. Understanding the physical and chemical nature of the warfarin drug binding site in human serum albumin: experimental and theoretical studies.

    Science.gov (United States)

    Abou-Zied, Osama K

    2015-01-01

    Human serum albumin (HSA) is one of the major carrier proteins in the body and constitutes approximately half of the protein found in blood plasma. It plays an important role in lipid metabolism, and its ability to reversibly bind a large variety of pharmaceutical compounds makes it a crucial determinant of drug pharmacokinetics and pharmacodynamics. This review deals with one of the protein's major binding sites "Sudlow I" which includes a binding pocket for the drug warfarin (WAR). The binding nature of this important site can be characterized by measuring the spectroscopic changes when a ligand is bound. Using several drugs, including WAR, and other drug-like molecules as ligands, the results emphasize the nature of Sudlow I as a flexible binding site, capable of binding a variety of ligands by adapting its binding pockets. The high affinity of the WAR pocket for binding versatile molecular structures stems from the flexibility of the amino acids forming the pocket. The binding site is shown to have an ionization ability which is important to consider when using drugs that are known to bind in Sudlow I. Several studies point to the important role of water molecules trapped inside the binding site in molecular recognition and ligand binding. Water inside the protein's cavity is crucial in maintaining the balance between the hydrophobic and hydrophilic nature of the binding site. Upon the unfolding and refolding of HSA, more water molecules are trapped inside the binding site which cause some swelling that prevents a full recovery from the denatured state. Better understanding of the mechanism of binding in macromolecules such as HSA and other proteins can be achieved by combining experimental and theoretical studies which produce significant synergies in studying complex biochemical phenomena.

  11. The effects of dissolved natural organic matter on the adsorption of synthetic organic chemicals by activated carbons and carbon nanotubes.

    Science.gov (United States)

    Zhang, Shujuan; Shao, Ting; Karanfil, Tanju

    2011-01-01

    Understanding the influence of natural organic matter (NOM) on synthetic organic contaminant (SOC) adsorption by carbon nanotubes (CNTs) is important for assessing the environmental implications of accidental CNT release and spill to natural waters, and their potential use as adsorbents in engineered systems. In this study, adsorption of two SOCs by three single-walled carbon nanotubes (SWNTs), one multi-walled carbon nanotube (MWNT), a microporous activated carbon fiber (ACF) [i.e., ACF10] and a bimodal porous granular activated carbon (GAC) [i.e., HD4000] was compared in the presence and absence of NOM. The NOM effect was found to depend strongly on the pore size distribution of carbons. Minimal NOM effect occurred on the macroporous MWNT, whereas severe NOM effects were observed on the microporous HD4000 and ACF10. Although the single-solute adsorption capacities of the SWNTs were much lower than those of HD4000, in the presence of NOM the SWNTs exhibited adsorption capacities similar to those of HD4000. Therefore, if released into natural waters, SWNTs can behave like an activated carbon, and will be able to adsorb, carry, and transfer SOCs to other systems. However, from an engineering application perspective, CNTs did not exhibit a major advantage, in terms of adsorption capacities, over the GAC and ACF. The NOM effect was also found to depend on molecular properties of SOCs. NOM competition was more severe on the adsorption of 2-phenylphenol, a nonplanar and hydrophilic SOC, than phenanthrene, a planar and hydrophobic SOC, tested in this study. In terms of surface chemistry, both adsorption affinity to SOCs and NOM effect on SOC adsorption were enhanced with increasing hydrophobicity of the SWNTs. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. Exploiting the Complementarity between Dereplication and Computer-Assisted Structure Elucidation for the Chemical Profiling of Natural Cosmetic Ingredients: Tephrosia purpurea as a Case Study.

    Science.gov (United States)

    Hubert, Jane; Chollet, Sébastien; Purson, Sylvain; Reynaud, Romain; Harakat, Dominique; Martinez, Agathe; Nuzillard, Jean-Marc; Renault, Jean-Hugues

    2015-07-24

    The aqueous-ethanolic extract of Tephrosia purpurea seeds is currently exploited in the cosmetic industry as a natural ingredient of skin lotions. The aim of this study was to chemically characterize this ingredient by combining centrifugal partition extraction (CPE) as a fractionation tool with two complementary identification approaches involving dereplication and computer-assisted structure elucidation. Following two rapid fractionations of the crude extract (2 g), seven major compounds namely, caffeic acid, quercetin-3-O-rutinoside, ethyl galactoside, ciceritol, stachyose, saccharose, and citric acid, were unambiguously identified within the CPE-generated simplified mixtures by a recently developed (13)C NMR-based dereplication method. The structures of four additional compounds, patuletin-3-O-rutinoside, kaempferol-3-O-rutinoside, guaiacylglycerol 8-vanillic acid ether, and 2-methyl-2-glucopyranosyloxypropanoic acid, were automatically elucidated by using the Logic for Structure Determination program based on the interpretation of 2D NMR (HSQC, HMBC, and COSY) connectivity data. As more than 80% of the crude extract mass was characterized without need for tedious and labor-intensive multistep purification procedures, the identification tools involved in this work constitute a promising strategy for an efficient and time-saving chemical profiling of natural extracts.

  13. Satellite remote sensing of harmful algal blooms: A new multi-algorithm method for detecting the Florida Red Tide (Karenia brevis)

    Science.gov (United States)

    Carvalho, Gustavo A.; Minnett, Peter J.; Fleming, Lora E.; Banzon, Viva F.; Baringer, Warner

    2010-01-01

    In a continuing effort to develop suitable methods for the surveillance of Harmful Algal Blooms (HABs) of Karenia brevis using satellite radiometers, a new multi-algorithm method was developed to explore whether improvements in the remote sensing detection of the Florida Red Tide was possible. A Hybrid Scheme was introduced that sequentially applies the optimized versions of two pre-existing satellite-based algorithms: an Empirical Approach (using water-leaving radiance as a function of chlorophyll concentration) and a Bio-optical Technique (using particulate backscatter along with chlorophyll concentration). The long-term evaluation of the new multi-algorithm method was performed using a multi-year MODIS dataset (2002 to 2006; during the boreal Summer-Fall periods – July to December) along the Central West Florida Shelf between 25.75°N and 28.25°N. Algorithm validation was done with in situ measurements of the abundances of K. brevis; cell counts ≥1.5×104 cells l−1 defined a detectable HAB. Encouraging statistical results were derived when either or both algorithms correctly flagged known samples. The majority of the valid match-ups were correctly identified (~80% of both HABs and non-blooming conditions) and few false negatives or false positives were produced (~20% of each). Additionally, most of the HAB-positive identifications in the satellite data were indeed HAB samples (positive predictive value: ~70%) and those classified as HAB-negative were almost all non-bloom cases (negative predictive value: ~86%). These results demonstrate an excellent detection capability, on average ~10% more accurate than the individual algorithms used separately. Thus, the new Hybrid Scheme could become a powerful tool for environmental monitoring of K. brevis blooms, with valuable consequences including leading to the more rapid and efficient use of ships to make in situ measurements of HABs. PMID:21037979

  14. The Natural Selection of the Chemical Elements (by R. J. P. Williams and J. J. R. Fraústo da Silva)

    Science.gov (United States)

    Kauffman, George B.

    1998-12-01

    Clarendon: New York, 1996. xxvi + 646 pp. Figs., tables. 20.5 x 25.6 cm. ISBN 0-19-855843-0. $80.00. R. J. P. Williams, Royal Society Research Professor Emeritus at Wadham College, Oxford University, and J. J. R. Fraústo da Silva, Professor of Analytical Chemistry at the Instituto Superior Técnico, Universidade Técnica de Lisboa, have collaborated on two previous volumes: New Trends in Bio-inorganic Chemistry (1978) and The Biological Chemistry of the Elements (3rd printing, 1994). Their latest collaborative effort is a book whose ambitious objective is "to show the relationship of every kind of material around us, living and nonliving, to the properties of the chemical elements of the periodic table." The "natural selection" of the chemical elements results from a number of factors, all of which are described in detail. Among these are chemical affinity related to the electronic configuration of their atoms, thermodynamic and kinetic stability, and "functional value to an organisation such as a living system". The physicist's approach to material through phase structure and the phase rule is stressed rather than the chemist's approach through bonding theories. The entire book possesses a strong environmental and interdisciplinary emphasis.

  15. Evolution of Chemical Diversity in a Group of Non-Reduced Polyketide Gene Clusters: Using Phylogenetics to Inform the Search for Novel Fungal Natural Products

    Directory of Open Access Journals (Sweden)

    Kurt Throckmorton

    2015-09-01

    Full Text Available Fungal polyketides are a diverse class of natural products, or secondary metabolites (SMs, with a wide range of bioactivities often associated with toxicity. Here, we focus on a group of non-reducing polyketide synthases (NR-PKSs in the fungal phylum Ascomycota that lack a thioesterase domain for product release, group V. Although widespread in ascomycete taxa, this group of NR-PKSs is notably absent in the mycotoxigenic genus Fusarium and, surprisingly, found in genera not known for their secondary metabolite production (e.g., the mycorrhizal genus Oidiodendron, the powdery mildew genus Blumeria, and the causative agent of white-nose syndrome in bats, Pseudogymnoascus destructans. This group of NR-PKSs, in association with the other enzymes encoded by their gene clusters, produces a variety of different chemical classes including naphthacenediones, anthraquinones, benzophenones, grisandienes, and diphenyl ethers. We discuss the modification of and transitions between these chemical classes, the requisite enzymes, and the evolution of the SM gene clusters that encode them. Integrating this information, we predict the likely products of related but uncharacterized SM clusters, and we speculate upon the utility of these classes of SMs as virulence factors or chemical defenses to various plant, animal, and insect pathogens, as well as mutualistic fungi.

  16. Inactivation of Escherichia coli, Saccharomyces cerevisiae, and Lactobacillus brevis in Low-fat Milk by Pulsed Electric Field Treatment: A Pilot-scale Study

    OpenAIRE

    Lee, Gun Joon; Han, Bok Kung; Choi, Hyuk Joon; Kang, Shin Ho; Baick, Seung Chun; Lee, Dong-Un

    2015-01-01

    We investigated the effects of a pulsed electric field (PEF) treatment on microbial inactivation and the physical properties of low-fat milk. Milk inoculated with Escherichia coli, Saccharomyces cerevisiae, or Lactobacillus brevis was supplied to a pilot-scale PEF treatment system at a flow rate of 30 L/h. Pulses with an electric field strength of 10 kV/cm and a pulse width of 30 ?s were applied to the milk with total pulse energies of 50-250 kJ/L achieved by varying the pulse frequency. The ...

  17. How José Limón's Cultural Identity Influenced Three of His Choreographic Works: Danzas Mexicanas (1939), La Malinche (1949), and Missa Brevis (1958)

    OpenAIRE

    Lanuza, Celeste

    2015-01-01

    This research focuses on the life and work of José Limón, (1908-1972), one of the most influential figures in twentieth-century modern concert dance. The way in which his Mexican and immigrant heritage influenced his unique contribution to American modern dance will be discussed in relation to three of his works: Danzas Mexicanas (1939), La Malinche (1949), and Missa Brevis (1958). As a dancer of Mexican heritage, I seek to better understand my artistic path and potential through this study o...

  18. Operation of the NETL Chemical Looping Reactor with Natural Gas and a Novel Copper-Iron Material

    Energy Technology Data Exchange (ETDEWEB)

    Straub, Douglas [National Energy Technology Lab. (NETL), Morgantown, WV (United States); Bayham, Samuel [National Energy Technology Lab. (NETL), Morgantown, WV (United States); Weber, Justin [National Energy Technology Lab. (NETL), Morgantown, WV (United States)

    2017-02-21

    The proposed Clean Power Plan requires CO2 emission reductions of 30% by 2030 and further reductions are targeted by 2050. The current strategies to achieve the 30% reduction targets do not include options for coal. However, the 2016 Annual Energy Outlook suggests that coal will continue to provide more electricity than renewable sources for many regions of the country in 2035. Therefore, cost effective options to reduce greenhouse gas emissions from fossil fuel power plants are vital in order to achieve greenhouse gas reduction targets beyond 2030. As part of the U.S. Department of Energy’s Advanced Combustion Program, the National Energy Technology Laboratory’s Research and Innovation Center (NETL R&IC) is investigating the feasibility of a novel combustion concept in which the GHG emissions can be significantly reduced. This concept involves burning fuel and air without mixing these two reactants. If this concept is technically feasible, then CO2 emissions can be significantly reduced at a much lower cost than more conventional approaches. This indirect combustion concept has been called Chemical Looping Combustion (CLC) because an intermediate material (i.e., a metal-oxide) is continuously cycled to oxidize the fuel. This CLC concept is the focus of this research and will be described in more detail in the following sections. The solid material that is used to transport oxygen is called an oxygen carrier material. The cost, durability, and performance of this material is a key issue for the CLC technology. Researchers at the NETL R&IC have developed an oxygen carrier material that consists of copper, iron, and alumina. This material has been tested extensively using lab scale instruments such as thermogravimetric analysis (TGA), scanning electron microscopy (SEM), mechanical attrition (ASTM D5757), and small fluidized bed reactor tests. This report will describe the results from a realistic, circulating, proof-of-concept test that was

  19. Tritium analysis in natural waters: experimental characteristics of the electrolitic enrichment system of the Chemical Department - Sao Carlos Federal University

    International Nuclear Information System (INIS)

    Mozeto, A.A.; Fontanetti, A.R.

    1986-01-01

    The working conditions of a system for low-level tritium analyses in natural waters were determined using eletrolytic enrichment and liquid scintillation counting techniques. The system installed at the Departamento de Quimica - UFScar is characterized by the following experimental parameters: (a) sample volume reduction factor during eletrolysis = 16.7; (b) tritium recovery factor = 80%; (c) tritium enrichment factor = 13.4; (d) counting efficiency = 12.5%; (e) background level = 11.5 cpm; (f) counting time per sample = 500 minutes; (g) sensitivity = 8.3 TU/cpm; (h) lower detection limit = 3.6 TU + - 50% and (i) analytical capacity = 30 samples/month. It is also discussed the suitability of the analytical system in terms of rain and ground water samples as well. (Author) [pt

  20. Smooth perfluorinated surfaces with different chemical and physical natures: their unusual dynamic dewetting behavior toward polar and nonpolar liquids.

    Science.gov (United States)

    Cheng, Dalton F; Masheder, Benjamin; Urata, Chihiro; Hozumi, Atsushi

    2013-09-10

    The effects of surface chemistry and the mobility of surface-tethered functional groups of various perfluorinated surfaces on their dewetting behavior toward polar (water) and nonpolar (n-hexadecane, n-dodecane, and n-decane) liquids were investigated. In this study, three types of common smooth perfluorinated surfaces, that is, a perfluoroalkylsilane (heptadecafluoro-1,1,2,2-tetrahydrooctyl-dimethylchlorosilane, FAS17) monomeric layer, an amorphous fluoropolymer film (Teflon AF 1600), and a perfluorinated polyether (PFPE)-terminated polymer brush film (Optool DSX), were prepared and their static/dynamic dewetting characteristics were compared. Although the apparent static contact angles (CAs) of these surfaces with all probe liquids were almost identical to each other, the ease of movement of liquid drops critically depended on the physical (solidlike or liquidlike) natures of the substrate surface. CA hysteresis and substrate tilt angles (TAs) of all probe liquids on the Optool DSX surface were found to be much lower than those of Teflon AF1600 and FAS17 surfaces due to its physical polymer chain mobility at room temperature and the resulting liquidlike nature. Only 6.0° of substrate incline was required to initiate movement for a small drop (5 μL) of n-decane, which was comparable to the reported substrate TA value (5.3°) for a superoleophobic surface (θ(S) > 160°, textured perfluorinated surface). Such unusual dynamic dewetting behavior of the Optool DSX surface was also markedly enhanced due to the significant increase in the chain mobility of PFPE by moderate heating (70 °C) of the surface, with substrate TA reducing to 3.0°. CA hysteresis and substrate TAs rather than static CAs were therefore determined to be of greater consequence for the estimation of the actual dynamic dewetting behavior of alkane probe liquids on these smooth perfluorinated surfaces. Their dynamic dewettability toward alkane liquids is in the order of Optool DSX > Teflon AF1600

  1. Effect of the nature the carbon precursor on the physico-chemical characteristics of the resulting activated carbon materials

    International Nuclear Information System (INIS)

    Jimenez, Vicente; Sanchez, Paula; Valverde, Jose Luis; Romero, Amaya

    2010-01-01

    Carbon materials, including amorphous carbon, graphite, carbon nanospheres (CNSs) and different types of carbon nanofibers (CNFs) [platelet, herringbone and ribbon], were chemically activated using KOH. The pore structure of carbon materials was analyzed using N 2 /77 K adsorption isotherms. The presence of oxygen groups was analyzed by temperature programmed desorption in He and acid-base titration. The structural order of the materials was studied by X-ray diffraction and temperature programmed oxidation. The morphology and diameter distribution of CNFs and CNSs were characterized by transmission electron microscopy. The materials were also characterized by temperature-desorption programmed of H 2 and elemental composition. The ways in which the different structures were activated are described, showing the type of pores generated. Relationships between carbon yield, removed carbon, activation degree and graphitic character were also examined. The oxygen content in the form of oxygen-containing surface groups increased after the activation giving qualitative information about them. The average diameter of both CNFs and CNSs was decreased after the activation process as consequence of the changes produced on the material surface.

  2. Effect of the nature the carbon precursor on the physico-chemical characteristics of the resulting activated carbon materials

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, Vicente, E-mail: vicente.jimenez@uclm.es [Facultad de Ciencias Quimicas, Departamento de Ingenieria Quimica, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Sanchez, Paula; Valverde, Jose Luis [Facultad de Ciencias Quimicas, Departamento de Ingenieria Quimica, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Romero, Amaya [Escuela Tecnica Agricola, Departamento de Ingenieria Quimica, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain)

    2010-11-01

    Carbon materials, including amorphous carbon, graphite, carbon nanospheres (CNSs) and different types of carbon nanofibers (CNFs) [platelet, herringbone and ribbon], were chemically activated using KOH. The pore structure of carbon materials was analyzed using N{sub 2}/77 K adsorption isotherms. The presence of oxygen groups was analyzed by temperature programmed desorption in He and acid-base titration. The structural order of the materials was studied by X-ray diffraction and temperature programmed oxidation. The morphology and diameter distribution of CNFs and CNSs were characterized by transmission electron microscopy. The materials were also characterized by temperature-desorption programmed of H{sub 2} and elemental composition. The ways in which the different structures were activated are described, showing the type of pores generated. Relationships between carbon yield, removed carbon, activation degree and graphitic character were also examined. The oxygen content in the form of oxygen-containing surface groups increased after the activation giving qualitative information about them. The average diameter of both CNFs and CNSs was decreased after the activation process as consequence of the changes produced on the material surface.

  3. Chemical variability of water and sediment over time and along a mountain river subjected to natural and human impact

    Directory of Open Access Journals (Sweden)

    Szarek-Gwiazda Ewa

    2018-01-01

    Full Text Available We studied the variability of physico-chemical parameters in water, and heavy metal contents in water and sediment over time and along the Carpathian Biała Tarnowska River (southern Poland and related them to catchment geology, human impact and the effect of barriers as a side aspect. The river water was well oxygenated, had pH 7.7–9.5 and was characterised by low and average flow. Temperature, pH and dissolved oxygen did not change significantly, while the contents of major ions, NO3−, NH4+, Mn and Fe increased gradually along the river. The major ion contents were negatively, and nitrate, Mn, and Fe positively, correlated with the flow. We recognise correlations between nitrate, Fe and Mn to be good indicators of soil erosion processes in the catchment. River sediment was unpolluted by most of the studied metals (slightly polluted by Ni and Cd. The differences in the values of some parameters (pH and NH4+, PO43−, HCO3−, Mn, Cd and Pb concentrations in the water, and heavy metals in the sediment upstream and downstream of some of the barriers were determined. Spatiotemporal changes in the values of studied parameters and the results of statistical calculation indicate the impact of human activity in the catchment basin (land use, wastewater on the water chemistry.

  4. Chemical and isotopic characteristics of the coso east flankhydrothermal fluids: implications for the location and nature of the heatsource

    Energy Technology Data Exchange (ETDEWEB)

    Christenson, B.W.; Kennedy, B.M.; Adams, M.C.; Bjornstad, S.C.; Buck, C.

    2007-01-08

    Fluids have been sampled from 9 wells and 2 fumaroles fromthe East Flank of the Coso hydrothermal system with a view toidentifying, if possible, the location and characteristics of the heatsource inflows into this portion of the geothermal field. Preliminaryresults show that there has been extensive vapor loss in the system, mostprobably in response to production. Wells 38A-9, 51-16 and 83A-16 showthe highest CO2-CO-CH4-H2 chemical equilibration temperatures, rangingbetween 300-340oC, and apart from 38A-9, the values are generally inaccordance with the measured temperatures in the wells. Calculatedtemperatures for the fractionation of 13C between CO2 and CH4 are inexcess of 400oC in fluids from wells 38A-9, 64-16-RD2 and 51A-16,obviously pointing to equilibrium conditions from deeper portions of thereservoir. Given that the predominant reservoir rock lithologies in theCoso system are relatively silicic (granitic to dioritic), the isotopicsignatures appear to reflect convective circulation and equilibrationwithin rocks close to the plastic-brittle transition. 3He/4He signatures,in conjunction with relative volatile abundances in the Coso fluids,point to a possibly altered mantle source for the heat sourcefluids.

  5. Changes in soil physical and chemical properties in long term improved natural and traditional agroforestry management systems of cacao genotypes in Peruvian Amazon.

    Science.gov (United States)

    Arévalo-Gardini, Enrique; Canto, Manuel; Alegre, Julio; Loli, Oscar; Julca, Alberto; Baligar, Virupax

    2015-01-01

    Growing cacao (Theobroma cacao L.) in an agroforestry system generates a productive use of the land, preserves the best conditions for physical, chemical and biological properties of tropical soils, and plays an important role in improving cacao production and fertility of degraded tropical soils. The aim of this study was to evaluate the impact of two long term agroforestry systems of cacao management on soil physical and chemical properties in an area originally inhabited by 30 years old native secondary forest (SF). The two agroforestry systems adapted were: improved natural agroforestry system (INAS) where trees without economic value were selectively removed to provide 50% shade and improved traditional agroforestry system (ITAS) where all native trees were cut and burnt in the location. For evaluation of the changes of soil physical and chemical properties with time due to the imposed cacao management systems, plots of 10 cacao genotypes (ICS95, UF613, CCN51, ICT1112, ICT1026, ICT2162, ICT2171, ICT2142, H35, U30) and one plot with a spontaneous hybrid were selected. Soil samples were taken at 0-20, 20-40 and 40-60 cm depths before the installation of the management systems (2004), and then followed at two years intervals. Bulk density, porosity, field capacity and wilting point varied significantly during the years of assessment in the different soil depths and under the systems assessed. Soil pH, CEC, exchangeable Mg and sum of the bases were higher in the INAS than the ITAS. In both systems, SOM, Ext. P, K and Fe, exch. K, Mg and Al+H decreased with years of cultivation; these changes were more evident in the 0-20 cm soil depth. Overall improvement of SOM and soil nutrient status was much higher in the ITAS than INAS. The levels of physical and chemical properties of soil under cacao genotypes showed a marked difference in both systems.

  6. Study of chemical composition of sludges and scales from the oil production activities and correlation with natural radioactivity - case study: Campos Basin, Brazil

    International Nuclear Information System (INIS)

    Cruz, Rosana Petinatti da

    2002-01-01

    This work intended to study general aspects related to natural radioactivity, focusing on its occurrence in the oil industry and on sludge and scales samples taken from the Oil E and P region from Campos's Basin. The physical and chemical analysis and the statistical treatment were carried out with the objective of determine the samples composition checking the differences between the sludges and the scales. Third six representative samples were obtained from the Radioprotection and Dosimetry Institute (IRD/CNEN), Brazil, taking into account factors such as activity concentration, physical and chemical aspects and origin. After the oil extraction, samples were classified by aspects as color and granulometry. Ali the studied samples were analyzed by X-rays diffraction being identified the presence of barite, calcite, quartz among others. The results supplied a base for the elaboration of a successive determination scheme which comprehended residual organic material, carbonate, sulfate, silica, chloride and metals as the alkaline, earthy alkaline, aluminum, etc. The sludges presented a highly variable chemical composition, being rich in silica and carbonates. The main components analysis showed a statistical valid relationship among the radium isotopes and the carbonates presence. On the other hand, the scales are made of barium and strontium sulfates (75%), presenting a minor variation on its chemical composition and in the existing radium content. Due to this low variability of the barium, sulfate and radium contents, it has not been possible to consider valid a relationship that could exist among them in the application of the main component analysis. (author)

  7. Light history modulates antioxidant and photosynthetic responses of biofilms to both natural (light) and chemical (herbicides) stressors.

    Science.gov (United States)

    Bonnineau, Chloé; Sague, Irene Gallardo; Urrea, Gemma; Guasch, Helena

    2012-05-01

    In multiple stress situations, the co-occurrence of environmental and chemical factors can influence organisms' ability to cope with toxicity. In this context, the influence of light adaptation on the response of freshwater biofilms to sudden light changes or to herbicides exposure was investigated by determining various parameters: diatom community composition, photosynthetic parameters, chlorophyll a content, antioxidant enzyme activities. Biofilms were grown in microcosms under sub-optimal, saturating, and high light intensities and showed already described characteristics of shade/light adaptation (community structure, photosynthetic adaptation, etc.). Light history modulated antioxidant and photosynthetic responses of biofilms to the stress caused by short-term exposure to sudden light changes or to herbicides. First biofilms adapted to sub-optimal light intensity (shade-adapted) were found to be more sensitive to an increase in light intensity than high-light adapted ones to a reduction in light intensity. Second, while light history influenced biofilms' response to glyphosate, it had little influence on biofilms' response to copper and none on its response to oxyfluorfen. Indeed glyphosate exposure led to a stronger decrease in photosynthetic efficiency of shade-adapted biofilms (EC(50) = 11.7 mg L(-1)) than of high-light adapted communities (EC(50) = 35.6 mg L(-1)). Copper exposure led to an activation of ascorbate peroxidase (APX) in biofilms adapted to sub-optimal and saturating light intensity while the protein content decreased in all biofilms exposed to copper. Oxyfluorfen toxicity was independent of light history provoking an increase in APX activity. In conclusion this study showed that both previous exposure to contaminants and physical habitat characteristics might influence community tolerance to disturbances strongly.

  8. Potential impacts on groundwater resources of deep CO2 storage: natural analogues for assessing potential chemical effects

    Science.gov (United States)

    Lions, J.; Gale, I.; May, F.; Nygaard, E.; Ruetters, H.; Beaubien, S.; Sohrabi, M.; Hatzignatiou, D. G.; CO2GeoNet Members involved in the present study Team

    2011-12-01

    Carbon dioxide Capture and Storage (CCS) is considered as one of the promising options for reducing atmospheric emissions of CO2 related to human activities. One of the main concerns associated with the geological storage of CO2 is that the CO2 may leak from the intended storage formation, migrate to the near-surface environment and, eventually, escape from the ground. This is a concern because such leakage may affect aquifers overlying the storage site and containing freshwater that may be used for drinking, industry and agriculture. The IEA Greenhouse Gas R&D Programme (IEAGHG) recently commissioned the CO2GeoNet Association to undertake a review of published and unpublished literature on this topic with the aim of summarizing 'state of the art' knowledge and identifying knowledge gaps and research priorities in this field. Work carried out by various CO2GeoNet members was also used in this study. This study identifies possible areas of conflict by combining available datasets to map the global and regional superposition of deep saline formations (DSF) suitable for CO2 storage and overlying fresh groundwater resources. A scenario classification is developed for the various geological settings where conflict could occur. The study proposes two approaches to address the potential impact mechanisms of CO2 storage projects on the hydrodynamics and chemistry of shallow groundwater. The first classifies and synthesizes changes of water quality observed in natural/industrial analogues and in laboratory experiments. The second reviews hydrodynamic and geochemical models, including coupled multiphase flow and reactive transport. Various models are discussed in terms of their advantages and limitations, with conclusions on possible impacts on groundwater resources. Possible mitigation options to stop or control CO2 leakage are assessed. The effect of CO2 pressure in the host DSF and the potential effects on shallow aquifers are also examined. The study provides a review of

  9. Physico-chemical forms of natural radionuclides in drilled well waters and their removal by ion exchange

    International Nuclear Information System (INIS)

    Vaaramaa, K.

    2003-01-01

    Appreciable concentrations of natural uranium and its daughter radionuclides may occur in drinking water obtained from drilled wells when the bedrock contains these nuclides. Effective methods are needed to remove these radionuclides. A wide range of ion exchange materials, both organic and inorganic, were evaluated for the removal of 234,238 U, 226 Ra, 210 Po and 210 Pb from ground waters. Screenin tests were carried out, in which distribution coefficients (KD) were determined for the ion exchangers. The ion exchangers that gave the highest KD's were tested in column-mode experiments for the removal of the radionuclides from drilled well water. The most efficient exchanger for the removal of U from neutral and slightly alkaline waters was the strong base anion resin. The chelating aminophosphonate resin removed uranium very efficiently from slightly acidic water. As well, it was an efficient exchanger for the removal of toxic and harmful transition metals from drilled well waters. The strong and weak acid cation resins and zeolite A removed radium most efficiently. Large fractions of the total activity of polonium and lead were found to adsorb on equipment in the ion exchange studies. In investigation of this, the well waters were filtered through membranes to determine the soluble and particle-bound forms of 234,238 U, 226 Ra, 210 Po and 210 Pb. Eight of the waters were of Ca type and two were of Na-Cl type. Some of the waters also had high concentrations of Fe, Mn and humic substances. Uranium was present entirely in soluble form, probably as uranyl ion in soluble carbonate complexes. 226 Ra was in soluble form in the waters with low concentrations of Fe and Mn, but 10% of the total radium activity was bound to particles in Fe-Mn-rich waters. The speciation of Po is complex in natural waters; polonium was present in both soluble and particle-bound forms. A correlation was observed between the fractions of particle-bound 210 Po and the concentrations of iron in

  10. Surface Display of the Receptor-Binding Region of the Lactobacillus brevis S-Layer Protein in Lactococcus lactis Provides Nonadhesive Lactococci with the Ability To Adhere to Intestinal Epithelial Cells

    OpenAIRE

    Åvall-Jääskeläinen, Silja; Lindholm, Agneta; Palva, Airi

    2003-01-01

    Lactobacillus brevis is a promising lactic acid bacterium for use as a probiotic dietary adjunct and a vaccine vector. The N-terminal region of the S-layer protein (SlpA) of L. brevis ATCC 8287 was recently shown to mediate adhesion to various human cell lines in vitro. In this study, a surface display cassette was constructed on the basis of this SlpA receptor-binding domain, a proteinase spacer, and an autolysin anchor. The cassette was expressed under control of the nisA promoter in Lactoc...

  11. Multi-method study of the characteristic chemical nature of aquatic humic substances isolated from the Han River, Korea

    International Nuclear Information System (INIS)

    Kim, Hyun-Chul; Yu, Myong-Jin; Han, Ihnsup

    2006-01-01

    Natural organic matter (NOM) from the Han River, Korea was fractionated into humic and non-humic fractions by absorbing onto XAD-7HP, and these fractions were analyzed using UV-absorption, and for dissolved organic C (DOC). The humic fraction (i.e. humic substances; HS) was extracted and its characteristics were compared to commercial humic materials using various spectroscopic methods such as Fourier transform infrared (FT-IR), proton nuclear magnetic resonance ( 1 H-NMR) and fluorescence spectroscopy. The humic fraction as organic C was 47.0% on the average, however, a rainfall event brought a higher humic fraction into Han River water. The molar ratios of H/C and O/C in the HS from Han River water (HRHS) were 1.40 and 0.76, respectively, and the ratio of aliphatic to aromatic protons in the HS (P Al /P Ar ratio) was 5.8. Aromaticity and humification degree (i.e., degree of condensation) of HRHS were relatively lower than those from other humic materials, while the portion of oxygenated functional groups was relatively higher. FT-IR, 1 H-NMR and fluorescence spectroscopy showed distinct differences between HRHS and the commercial humic materials. Commercial humic materials are not representative of HS extracted from Han River water. The fluorescence spectra, relatively simple measurements, were found to be most useful as fingerprints for humic materials from particular sources

  12. Biological and chemical evaluation of sewage water pollution in the Rietvlei nature reserve wetland area, South Africa

    International Nuclear Information System (INIS)

    Oberholster, P.J.; Botha, A.-M.; Cloete, T.E.

    2008-01-01

    Macroinvertebrate communities in Rietvlei nature reserve wetland area and their relationship with water quality were studied with the aim to evaluate their use as potential indicators of pollution. Sampling locations were selected to include outlets from swage effluent, agricultural and informal residential runoff. A large increase in nutrient concentrations was observed downstream from discharged treated sewage with an associated decrease in species richness. Bioassays performed included: Daphnia magna, Hydra attenuate, Lactuca sativa, Allium cepa and Pyxicephalus adspersus. The highest percentage of lethality response to a screen (100% concentration) of sampled wetland water by test specimens were observed at the point source input of the Hartbeespoort treated sewage plant. Data generated from the AUSRIVAS method and multitrophic level bioassays revealed the deterioration of the wetland possibly due to factors such as increasing urbanization, industrialization, agriculture runoff and rapid human settlement in the Hennops River catchment area and its principal tributaries. - Bioassays confirmed the degradation of a freshwater wetland system due to effluent from a variety of sources

  13. Biological and chemical evaluation of sewage water pollution in the Rietvlei nature reserve wetland area, South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Oberholster, P.J. [CSIR Natural Resources and the Environment, P.O. Box 395, Pretoria 0001 (South Africa)], E-mail: anna.oberholster@up.ac.za; Botha, A.-M. [Department of Genetics, University of Pretoria, Hillcrest, Pretoria ZA002 (South Africa); Cloete, T.E. [Department of Microbiology and Plant Pathology, University of Pretoria, Hillcrest, Pretoria ZA002 (South Africa)

    2008-11-15

    Macroinvertebrate communities in Rietvlei nature reserve wetland area and their relationship with water quality were studied with the aim to evaluate their use as potential indicators of pollution. Sampling locations were selected to include outlets from swage effluent, agricultural and informal residential runoff. A large increase in nutrient concentrations was observed downstream from discharged treated sewage with an associated decrease in species richness. Bioassays performed included: Daphnia magna, Hydra attenuate, Lactuca sativa, Allium cepa and Pyxicephalus adspersus. The highest percentage of lethality response to a screen (100% concentration) of sampled wetland water by test specimens were observed at the point source input of the Hartbeespoort treated sewage plant. Data generated from the AUSRIVAS method and multitrophic level bioassays revealed the deterioration of the wetland possibly due to factors such as increasing urbanization, industrialization, agriculture runoff and rapid human settlement in the Hennops River catchment area and its principal tributaries. - Bioassays confirmed the degradation of a freshwater wetland system due to effluent from a variety of sources.

  14. A natural analogue for high-level waste in tuff: Chemical analysis and modeling of the Valles site

    International Nuclear Information System (INIS)

    Stockman, H.W.; Krumhansl, J.L.; Ho, C.K.; Kovach, L.; McConnell, V.S.

    1995-01-01

    The contact between an obsidian flow and a steep-walled tuff canyon was examined as an analogue for a high-level waste repository. The analogue site is located in the Valles Caldera in New Mexico, where a massive obsidian flow filled a paleocanyon in the Battleship Rock Tuff. The obsidian flow provided a heat source, analogous to waste panels or an igneous intrusion in a repository, and caused evaporation and migration of water. The tuff and obsidian samples were analyzed for major and trace elements and mineralogy by INAA, XRF, x-ray diffraction, and scanning electron microscopy and electron microprobe. Samples were also analyzed for D/H and 39 Ar/ 40 Ar isotopic composition. Overall, the effects of the heating event seem to have been slight and limited to the tuff nearest the contact. There is some evidence of devitrification and migration of volatiles in the tuff within 10 m of the contact, but variations in major and trace element chemistry are small and difficult to distinguish from the natural (pre-heating) variability of the rocks

  15. Possible Protective Effect of Low-dose Gamma Irradiation and Certain Natural Products on Chemically Induced Hepatotoxicity in Rats

    International Nuclear Information System (INIS)

    Rashed, R.R.A.

    2015-01-01

    Liver, the largest organ in the human body, is a vital organ that performs more than 500 vital metabolic functions. More than a 1000 drugs of the modern pharmacopoeia can induce liver injury with different clinical presentations. In the most severe cases, drug-induced liver injury may require liver transplantation or lead to death of the patient. Acetaminophen (acetyl-para-amino-phenol, paracetamol, APAP) is safe at therapeutic doses, but accidental or intentional overdose can induce severe hepatotoxicity in both humans and experimental animals. APAP-induced hepatotoxicity is dose related and reproducible in animals, and is thus widely used as a model for experimentally induced hepatotoxicity. Many herbs have been used as natural remedies for the prevention and/or treatment of liver diseases. Herbal drugs gained importance and popularity in recent years because of their safety, efficacy and cost effectiveness. Interestingly, exposure to a small dose or dose rate of radiation was reported to induce stress, perturbing homeostasis. Organisms respond adaptively to such disturbances. The mechanisms by which low-dose radiation (LDR) protects the cells or tissue against subsequent radiation- or drug-induced toxicities have been attributed to its stimulation of various protective molecules such as antioxidants and anti apoptotic. In the light of the above mentioned information, this study was constructed in order to investigate the mechanism(s) of the hepato protective effects offered by each of garlic oil (GO), black seed oil (BO) and sesame oil (SO) each alone or combined with low dose total body gamma (γ)-irradiation against APAP-induced hepatotoxicity in male albino Wistar rats. Preliminary pilot studies were performed prior to the main experimental work; in order to select the effective irradiation dose, the hepato protective natural products and the duration of their administration to be used in the main study. To carry out the main study, 96 rats were randomly

  16. Transcriptome analysis of beer-spoiling Lactobacillus brevis BSO 464 during growth in degassed and gassed beer.

    Science.gov (United States)

    Bergsveinson, Jordyn; Friesen, Vanessa; Ziola, Barry

    2016-10-17

    Lactobacillus brevis BSO 464 (Lb464) is a beer-spoilage-related (BSR) isolate of interest given its unique physiological attributes; specifically, it is highly hop-tolerant and exhibits very rapid growth in pressurized/gassed beer. RNA sequencing was performed on Lb464 grown in pressurized and non-pressurized beer to determine important genetic mechanisms for growth in these environments. The data generated were compared against data in a previous transcriptional study of another lactic acid bacterium (LAB) during growth in beer, namely, Pediococcus claussenii ATCC BAA-344(T) (Pc344). Results revealed that the most important genetic elements for Lb464 growth in beer are related to biogenic amine metabolism, membrane transport and fortification, nutrient scavenging, and efficient transcriptional regulation. Comparison with the previous transcriptional study of Pc344 indicated that the total coding capacity (plasmid profile and genome size) of a LAB isolate allows for beer-spoilage virulence and adaptation to different beer environments, i.e., the ability to grow in degassed beer (during production) or gassed beer (packaged product). Further, differences in gene expression of Lb464 and Pc344 during mid-exponential growth in beer may dictate how rapidly each isolate exhausts particular carbon sources during. The presence of headspace pressure/dissolved CO2 was found to drive Lb464 transcription during mid-exponential growth in beer towards increasing cell wall and membrane modification, transport, osmoregulation, and DNA metabolism and transposition events. This transcriptional activity resembles transcriptional patterns or signatures observed in a viable, but non-culturable state established by non-related organisms, suggesting that Lb464 overall uses complex cellular regulation to maintain cell division and growth in the stressful beer environment. Additionally, increased expression of several hypothetical proteins, the hop-tolerance gene horC, and DNA repair and

  17. The effect of Lactobacillus brevis KB290 against irritable bowel syndrome: a placebo-controlled double-blind crossover trial

    Directory of Open Access Journals (Sweden)

    Murakami Katsumi

    2012-08-01

    Full Text Available Abstract Background Irritable bowel syndrome (IBS is a functional disorder of the digestive tract that causes chronic abdominal symptoms. We evaluated the effects of Lactobacillus brevis KB290 (KB290, which has been demonstrated to be effective at improving bowel movements and the composition of intestinal microflora, on IBS symptoms. Methods We performed a placebo control double-blind cross matched trial. Thirty-five males and females (aged 6 years and above who had been diagnosed with IBS according to the Rome III criteria were divided into 2 groups, and after a 4-week pre-trial observation period, they were administered test capsules containing KB290 or placebo for 4 weeks (consumption period I. Then, the capsule administration was suspended for 4 weeks in both groups (washout period, before the opposite capsules were administered for a further 4 weeks (consumption period II. Fecal samples were collected on the first day of the pre-consumption observation period, the last day of consumption period I, the last day of the washout period, and the last day of consumption period II. In addition, the subjects’ IBS symptoms and quality of life (QOL and any adverse events that they experienced were evaluated. Results No significant difference in IBS symptoms was noted among the various periods. However, the mean QOL scores were improved during the test capsule consumption. The frequencies of watery and mushy feces were significantly lower in the test capsule consumption period than during the pre-consumption observation period, and the frequency of abdominal pain was significantly reduced in the test capsule consumption period compared with the other periods. The frequency of the genus Bifidobacterium was significantly higher, and that of the genus Clostridium was significantly lower, after the test capsule consumption than after the placebo consumption. The frequencies of the genera Lactobacillus, Bacteroides, and Enterococcus were also

  18. Inactivation of Escherichia coli, Saccharomyces cerevisiae, and Lactobacillus brevis in Low-fat Milk by Pulsed Electric Field Treatment: A Pilot-scale Study

    Science.gov (United States)

    Han, Bok Kung; Choi, Hyuk Joon; Kang, Shin Ho; Baick, Seung Chun

    2015-01-01

    We investigated the effects of a pulsed electric field (PEF) treatment on microbial inactivation and the physical properties of low-fat milk. Milk inoculated with Escherichia coli, Saccharomyces cerevisiae, or Lactobacillus brevis was supplied to a pilot-scale PEF treatment system at a flow rate of 30 L/h. Pulses with an electric field strength of 10 kV/cm and a pulse width of 30 μs were applied to the milk with total pulse energies of 50-250 kJ/L achieved by varying the pulse frequency. The inactivation curves of the test microorganisms were biphasic with an initial lag phase (or shoulder) followed by a phase of rapid inactivation. PEF treatments with a total pulse energy of 200 kJ/L resulted in a 4.5-log reduction in E. coli, a 4.4-log reduction in L. brevis, and a 6.0-log reduction in S. cerevisiae. Total pulse energies of 200 and 250 kJ/L resulted in greater than 5-log reductions in microbial counts in stored PEF-treated milk, and the growth of surviving microorganisms was slow during storage for 15 d at 4℃. PEF treatment did not change milk physical properties such as pH, color, or particle-size distribution (pelectric-field strength of 10 kV/cm can be used to pasteurize low-fat milk. PMID:26877640

  19. Hop resistance in the beer spoilage bacterium Lactobacillus brevis is mediated by the ATP-binding cassette multidrug transporter HorA.

    Science.gov (United States)

    Sakamoto, K; Margolles, A; van Veen, H W; Konings, W N

    2001-09-01

    Lactobacillus brevis is a major contaminant of spoiled beer. The organism can grow in beer in spite of the presence of antibacterial hop compounds that give the beer a bitter taste. The hop resistance in L. brevis is, at least in part, dependent on the expression of the horA gene. The deduced amino acid sequence of HorA is 53% identical to that of LmrA, an ATP-binding cassette multidrug transporter in Lactococcus lactis. To study the role of HorA in hop resistance, HorA was functionally expressed in L. lactis as a hexa-histidine-tagged protein using the nisin-controlled gene expression system. HorA expression increased the resistance of L. lactis to hop compounds and cytotoxic drugs. Drug transport studies with L. lactis cells and membrane vesicles and with proteoliposomes containing purified HorA protein identified HorA as a new member of the ABC family of multidrug transporters.

  20. Inactivation of Escherichia coli, Saccharomyces cerevisiae, and Lactobacillus brevis in Low-fat Milk by Pulsed Electric Field Treatment: A Pilot-scale Study.

    Science.gov (United States)

    Lee, Gun Joon; Han, Bok Kung; Choi, Hyuk Joon; Kang, Shin Ho; Baick, Seung Chun; Lee, Dong-Un

    2015-01-01

    We investigated the effects of a pulsed electric field (PEF) treatment on microbial inactivation and the physical properties of low-fat milk. Milk inoculated with Escherichia coli, Saccharomyces cerevisiae, or Lactobacillus brevis was supplied to a pilot-scale PEF treatment system at a flow rate of 30 L/h. Pulses with an electric field strength of 10 kV/cm and a pulse width of 30 μs were applied to the milk with total pulse energies of 50-250 kJ/L achieved by varying the pulse frequency. The inactivation curves of the test microorganisms were biphasic with an initial lag phase (or shoulder) followed by a phase of rapid inactivation. PEF treatments with a total pulse energy of 200 kJ/L resulted in a 4.5-log reduction in E. coli, a 4.4-log reduction in L. brevis, and a 6.0-log reduction in S. cerevisiae. Total pulse energies of 200 and 250 kJ/L resulted in greater than 5-log reductions in microbial counts in stored PEF-treated milk, and the growth of surviving microorganisms was slow during storage for 15 d at 4℃. PEF treatment did not change milk physical properties such as pH, color, or particle-size distribution (ppasteurize low-fat milk.

  1. An effect of humid climate on micro structure and chemical component of natural composite (Boehmeria nivea-Albizia falcata based wind turbine blade

    Directory of Open Access Journals (Sweden)

    Sudarsono S.

    2018-01-01

    Full Text Available In this work, wind turbine blade NACA 4415 is fabricated from natural composite of Boehmeria nivea and Albizia falcate. The composite fabrication method used is hand lay up method. The aim of the work is to investigate an effect of humid climate of coastal area on micro structure and chemical composition of composite material of the blade. The wind turbine is tested at Pantai Baru, Bantul, Yogyakarta for 5.5 months. The micro structure scanning is performed with Scanning Electron Microscope (SEM and material component is measured with Energy Dispersive X-ray spectrometer (EDS. The samples are tested before and after the use within 5.5 month at the location. The results show that composite material inexperienced interface degradation and insignificant change of micro structure. From EDS test, it is observed that Na filtration reduces C and increases O in composite material after 5.5 months.

  2. An effect of humid climate on micro structure and chemical component of natural composite (Boehmeria nivea-Albizia falcata) based wind turbine blade

    Science.gov (United States)

    Sudarsono, S.; Purwanto; Sudarsono, Johny W.

    2018-02-01

    In this work, wind turbine blade NACA 4415 is fabricated from natural composite of Boehmeria nivea and Albizia falcate. The composite fabrication method used is hand lay up method. The aim of the work is to investigate an effect of humid climate of coastal area on micro structure and chemical composition of composite material of the blade. The wind turbine is tested at Pantai Baru, Bantul, Yogyakarta for 5.5 months. The micro structure scanning is performed with Scanning Electron Microscope (SEM) and material component is measured with Energy Dispersive X-ray spectrometer (EDS). The samples are tested before and after the use within 5.5 month at the location. The results show that composite material inexperienced interface degradation and insignificant change of micro structure. From EDS test, it is observed that Na filtration reduces C and increases O in composite material after 5.5 months.

  3. Estimating pesticide sampling rates by the polar organic chemical integrative sampler (POCIS) in the presence of natural organic matter and varying hydrodynamic conditions

    Science.gov (United States)

    Charlestra, Lucner; Amirbahman, Aria; Courtemanch, David L.; Alvarez, David A.; Patterson, Howard

    2012-01-01

    The polar organic chemical integrative sampler (POCIS) was calibrated to monitor pesticides in water under controlled laboratory conditions. The effect of natural organic matter (NOM) on the sampling rates (Rs) was evaluated in microcosms containing -1 of total organic carbon (TOC). The effect of hydrodynamics was studied by comparing Rs values measured in stirred (SBE) and quiescent (QBE) batch experiments and a flow-through system (FTS). The level of NOM in the water used in these experiments had no effect on the magnitude of the pesticide sampling rates (p > 0.05). However, flow velocity and turbulence significantly increased the sampling rates of the pesticides in the FTS and SBE compared to the QBE (p < 0.001). The calibration data generated can be used to derive pesticide concentrations in water from POCIS deployed in stagnant and turbulent environmental systems without correction for NOM.

  4. Hot isostatically-pressed aluminosilicate glass-ceramic with natural crystalline analogues for immobilizing the calcined high-level nuclear waste at the Idaho Chemical Processing Plant

    International Nuclear Information System (INIS)

    Raman, S.

    1993-12-01

    The additives Si, Al, MgO, P 2 O 5 were mechanically blended with fluorinelsodium calcine in varying proportions. The batches were vacuum sealed in stainless steel canisters and hot isostatically pressed at 20,000 PSI and 1000 C for 4 hours. The resulting suite of glass-ceramic waste forms parallels the natural rocks in microstructural and compositional heterogeneity. Several crystalline phases ar analogous in composition and structure to naturally occurring minerals. Additional crystalline phases are zirconia and Ca-Mg borate. The glasses are enriched in silica and alumina. Approximately 7% calcine elements occur dissolved in this glass and the total glass content in the waste forms averages 20 wt%. The remainder of the calcine elements are partitioned into crystalline phases at 75 wt% calcine waste loading. The waste forms were tested for chemical durability in accordance with the MCC1-test procedure. The leach rates are a function of the relative proportions of additives and calcine, which in turn influence the composition and abundances of the glass and crystalline phases. The DOE leach rate criterion of less than 1 g/m 2 -day is met by all the elements B, Cs and Na are increased by lowering the melt viscosity. This is related to increased crystallization or devitrification with increases in MgO addition. This exploratory work has shown that the increases in waste loading occur by preferred partitioning of the calcine components among crystalline and glass phases. The determination of optimum processing parameters in the form of additive concentration levels, homogeneous blending among the components, and pressure-temperature stabilities of phases must be continued to eliminate undesirable effects of chemical composition, microstructure and glass devitrification

  5. Chemically reactive and naturally convective high speed MHD fluid flow through an oscillatory vertical porous plate with heat and radiation absorption effect

    Directory of Open Access Journals (Sweden)

    S.M. Arifuzzaman

    2018-04-01

    Full Text Available This paper concerns with the modelling of an unsteady natural convective and higher order chemically reactive magnetohydrodynamics (MHD fluid flow with the effect of heat and radiation absorption. The flow is generated through a vertical oscillating porous plate. Boundary layer approximations is carried out to establish a flow model which represents the time dependent momentum, energy and diffusion balance equations. Before being solved numerically, the governing partial differential equations (PDEs were transformed into a set of nonlinear ordinary differential equation (ODEs by using non-similar technique. A very efficient numerical approach solves the obtained nonlinear coupled ODEs so called Explicit Finite Difference Method (EFDM. An algorithm is implemented in Compaq Visual Fortran 6.6a as a solving tool. In addition, the stability and convergence analysis (SCA is examined and shown explicitly. The advantages of SCA is its optimizes the accuracy of system parameters such as Prandtl number (Pr and Schmidt number (Sc.The velocity, temperature and concentration fields in the boundary layer region are studied in detail and the outcomes are shown in graphically with the influence of various pertinent parameters such as Grashof number (Gr, modified Grashof number (Gr, magnetic parameter (M, Darcy number (Da,Prandtl number (Pr, Schmidt number (Sc, radiation (R, heat sink (Q,radiation absorption (Q1, Eckert number (Ec, Dufour number (Du,Soret number (Sr, Schmidt number (Sc, reaction index (P and chemical reaction (Kr. Furthermore, the effect of skin friction coefficient (Cf, Nusselt number (Nu and Sherwood number (Sh are also examined graphically. Keywords: MHD, Oscillating porous plate, Radiation absorption, High order chemical reaction, EFDM

  6. Mechanical properties of chemically modified Sansevieria trifasciata/natural rubber/high density polyethylene (STF/NR/HDPE) composites: Effect of silane coupling agent

    Science.gov (United States)

    Zakaria, Nurzam Ezdiani; Baharum, Azizah; Ahmad, Ishak

    2018-04-01

    The main objective of this research is to study the effects of chemical modification on the mechanical properties of treated Sansevieria trifasciata fiber/natural rubber/high density polyethylene (TSTF/NR/HDPE) composites. Processing of STF/NR/HDPE composites was done by using an internal mixer. The processing parameters used were 135°C for temperature and a mixing rotor speed of 55 rpm for 15 minutes. Filler loading was varied from 10% to 40% of STF and the fiber size used was 125 µm. The composite blends obtained then were pressed with a hot press machine to get test samples of 1 mm and 3 mm of thickness. Samples were evaluated via tensile tests, Izod impact test and scanning electron microscopy (SEM). Results showed that tensile strength and strain value decreased while tensile modulus increased when filler loading increased. Impact strength increased when filler loading increased and began to decrease after 10% of filler amount for treated composites. For untreated composites, impact strength began to decrease after 20% of filler loading. Chemical modification by using silane coupling agent has improved certain mechanical properties of the composites such as tensile strength, strain value and tensile modulus. Adding more amount of filler will also increase the viscosity and the stiffness of the materials.

  7. Estimating pesticide sampling rates by the polar organic chemical integrative sampler (POCIS) in the presence of natural organic matter and varying hydrodynamic conditions

    International Nuclear Information System (INIS)

    Charlestra, Lucner; Amirbahman, Aria; Courtemanch, David L.; Alvarez, David A.; Patterson, Howard

    2012-01-01

    The polar organic chemical integrative sampler (POCIS) was calibrated to monitor pesticides in water under controlled laboratory conditions. The effect of natural organic matter (NOM) on the sampling rates (R s ) was evaluated in microcosms containing −1 of total organic carbon (TOC). The effect of hydrodynamics was studied by comparing R s values measured in stirred (SBE) and quiescent (QBE) batch experiments and a flow-through system (FTS). The level of NOM in the water used in these experiments had no effect on the magnitude of the pesticide sampling rates (p > 0.05). However, flow velocity and turbulence significantly increased the sampling rates of the pesticides in the FTS and SBE compared to the QBE (p < 0.001). The calibration data generated can be used to derive pesticide concentrations in water from POCIS deployed in stagnant and turbulent environmental systems without correction for NOM. - Highlights: ► We assessed the effect of TOC and stirring on pesticide sampling rates by POCIS. ► Total organic carbon (TOC) had no effect on the sampling rates. ► Water flow and stirring significantly increased the magnitude of the sampling rates. ► The sampling rates generated are directly applicable to field conditions. - This study provides POCIS sampling rates data that can be used to estimate freely dissolved concentrations of toxic pesticides in natural waters.

  8. Relationships between persistent organic chemicals residues and biochemical constituents in fish from a protected area: the French National Nature Reserve of Camargue.

    Science.gov (United States)

    Roche, Hélène; Buet, Astrid; Ramade, François

    2002-11-01

    The Reserve of Biosphere of Camargue [French National Nature Reserve of Camargue (NNRC)] is a protected area frequently exposed to natural and anthropogenic environmental alterations. To evaluate potential contamination of fish with lipophilic chemicals-organochlorines (OCs) and polycyclic aromatic hydrocarbons (PAHs)-a biological monitoring survey was carried out. Metabolic reserve levels were evaluated to select appropriate biological indicators able to be significant biomarkers. In addition, the incorporation of xenobiotic molecules in the lipid compartments was investigated. The contents of glycogen, total lipids, proteins and lipidic phosphorus were analyzed in liver and skeletal muscles of three teleostean: the European eel (Anguilla anguilla); the crucian carp (Carassius auratus); and the catfish (Ictalurus melas). The atmospheric origin of the PAH detected in any season in the biomass and the OCs compounds contamination by derive from agricultural treatments are established. In contradiction with some laboratory acute intoxication studies, we observe a positive correlation between tissue concentrations of contaminants and the muscular glycogen amount, a sensitive energy reserve marker. Moreover, it seems likely that the incorporation of these xenobiotics is located preferentially in the membrane structures.

  9. “Prolungata convivenza” oltre le nozze e mancata “delibazione” della sentenza ecclesiastica di nullità matrimoniale (brevi note a Cass. civ., sez. I, sent. 20 gennaio 2011, n. 1343

    Directory of Open Access Journals (Sweden)

    Jlia Pasquali Cerioli

    2011-05-01

    Full Text Available SOMMARIO: 1. I fatti e il processo – 2. La sentenza – 3. Una decisa svolta giurisprudenziale – 4. Difficoltà applicative – 5. (segue… incerti futuri scenari - 6. Brevi conclusioni: la rinnovata vitalità del limite di ordine pubblico.

  10. Antimycobacterial natural products from Moroccan medicinal plants: Chemical composition, bacteriostatic and bactericidal profile of Thymus satureioides and Mentha pulegium essential oils

    Institute of Scientific and Technical Information of China (English)

    Marwa Chraibi; Abdellah Farah; Sara Lebrazi; Oumaima El Amine; Mohammed Iraqui Houssaini; Kawtar Fikri-Benbrahim

    2016-01-01

    Objective: To evaluate the susceptibility of Mycobacterium aurum and Mycobacterium smegmatis in vitro to the essential oils obtained from two medicinal plants: Thymus satureioides(T. satureioides) and Mentha pulegium(M. pulegium), and to study their chemical composition.Methods: The aerial parts of T. satureioides and M. pulegium(leaves and stems) were hydro-distillated using a Clevenger-type apparatus and essential oils were analyzed and identified by gas chromatography-mass spectrometry. Antimycobacterial screening of essential oils was performed on the basis of the inhibition zone diameter by disc diffusion method against two mycobacterial strains whereas the minimal inhibitory concentration and minimal bactericidal concentration were determined by using the micro-dilution method.Results: Chemical analysis of their aerial part’s essential oils gave as major compounds,borneol(34.26%), carvacrol(31.21%) and thymol(3.71%) for T. satureioides and R(+)-pulegone(75.48%), carvone(6.66%) and dihydrocarvone(4.64%) for M. pulegium.Thereafter their antimycobacterial effect evaluation, using the micro-dilution method,indicated that minimal inhibitory concentration values of T. satureioides essential oil ranged from 0.062% to 0.015%(v/v) and from 0.125% to 0.031%(v/v) for M. pulegium respectively against Mycobacterium aurum and Mycobacterium smegmatis.Conclusions: It is clearly evident from the results obtained that the Moroccan medicinal plants have great potential to be used as anti-tuberculosis agents. These findings may help scientists to undertake several research projects to discover useful natural product as new anti-tuberculosis drug.

  11. Antimycobacterial natural products from Moroccan medicinal plants:Chemical composition, bacteriostatic and bactericidal profile of Thymus satureioides and Mentha pulegium essential oils

    Institute of Scientific and Technical Information of China (English)

    Marwa Chraibi; Abdellah Farah; Sara Lebrazi; Oumaima El Amine; Mohammed Iraqui Houssaini; Kawtar Fikri-Benbrahim

    2016-01-01

    Objective: To evaluate the susceptibility of Mycobacterium aurum and Mycobacterium smegmatis in vitro to the essential oils obtained from two medicinal plants: Thymus satureioides (T. satureioides) and Mentha pulegium (M. pulegium), and to study their chemical composition. Methods: The aerial parts of T. satureioides and M. pulegium (leaves and stems) were hydro-distillated using a Clevenger-type apparatus and essential oils were analyzed and identified by gas chromatography-mass spectrometry. Antimycobacterial screening of essential oils was performed on the basis of the inhibition zone diameter by disc diffusion method against two mycobacterial strains whereas the minimal inhibitory concentration and minimal bactericidal concentration were determined by using the micro-dilution method. Results: Chemical analysis of their aerial part's essential oils gave as major compounds, borneol (34.26%), carvacrol (31.21%) and thymol (3.71%) for T. satureioides and R(+)-pulegone (75.48%), carvone (6.66%) and dihydrocarvone (4.64%) for M. pulegium. Thereafter their antimycobacterial effect evaluation, using the micro-dilution method, indicated that minimal inhibitory concentration values of T. satureioides essential oil ranged from 0.062%to 0.015%(v/v) and from 0.125%to 0.031%(v/v) for M. pulegium respectively against Mycobacterium aurum and Mycobacterium smegmatis. Conclusions: It is clearly evident from the results obtained that the Moroccan medicinal plants have great potential to be used as anti-tuberculosis agents. These findings may help scientists to undertake several research projects to discover useful natural product as new anti-tuberculosis drug.

  12. Exploring Natural Products from the Biodiversity of Pakistan for Computational Drug Discovery Studies: Collection, Optimization, Design and Development of A Chemical Database (ChemDP).

    Science.gov (United States)

    Mirza, Shaher Bano; Bokhari, Habib; Fatmi, Muhammad Qaiser

    2015-01-01

    Pakistan possesses a rich and vast source of natural products (NPs). Some of these secondary metabolites have been identified as potent therapeutic agents. However, the medicinal usage of most of these compounds has not yet been fully explored. The discoveries for new scaffolds of NPs as inhibitors of certain enzymes or receptors using advanced computational drug discovery approaches are also limited due to the unavailability of accurate 3D structures of NPs. An organized database incorporating all relevant information, therefore, can facilitate to explore the medicinal importance of the metabolites from Pakistani Biodiversity. The Chemical Database of Pakistan (ChemDP; release 01) is a fully-referenced, evolving, web-based, virtual database which has been designed and developed to introduce natural products (NPs) and their derivatives from the biodiversity of Pakistan to Global scientific communities. The prime aim is to provide quality structures of compounds with relevant information for computer-aided drug discovery studies. For this purpose, over 1000 NPs have been identified from more than 400 published articles, for which 2D and 3D molecular structures have been generated with a special focus on their stereochemistry, where applicable. The PM7 semiempirical quantum chemistry method has been used to energy optimize the 3D structure of NPs. The 2D and 3D structures can be downloaded as .sdf, .mol, .sybyl, .mol2, and .pdb files - readable formats by many chemoinformatics/bioinformatics software packages. Each entry in ChemDP contains over 100 data fields representing various molecular, biological, physico-chemical and pharmacological properties, which have been properly documented in the database for end users. These pieces of information have been either manually extracted from the literatures or computationally calculated using various computational tools. Cross referencing to a major data repository i.e. ChemSpider has been made available for overlapping

  13. Chemical and isotopic characterization of water-rock interactions in shales induced by the intrusion of a basaltic dike: A natural analogue for radioactive waste disposal

    International Nuclear Information System (INIS)

    Techer, Isabelle; Rousset, Davy; Clauer, Norbert; Lancelot, Joel; Boisson, Jean-Yves

    2006-01-01

    Disposal of nuclear waste in deep geological formations is expected to induce thermal fluxes for hundreds of years with maximum temperature reaching about 100-150 deg. C in the nearfield argillaceous environment. The long-term behavior of clays subjected to such thermal gradients needs to be perfectly understood in safety assessment considerations. In this respect, a Toarcian argillaceous unit thermally disturbed by the intrusion of a 1.1-m wide basaltic dike at the Perthus pass (Herault, France), was studied in detail as a natural analogue. The thermal imprint induced by the dike was evaluated by a mineralogical, chemical and K-Ar study of the <2 μm clay fraction of shale samples collected at increasing distance from the basalt. The data suggest that the mineral composition of the shales was not significantly disturbed when the temperature was below 100-150 deg. C. Closer to the dike at 150-300 deg. C, changes such as progressive dissolution of chlorite and kaolinite, increased content of the mixed layers illite-smectite with more illite layers, complete decalcification and subsequent increased content of quartz, were found. At the eastern contact with the dike, the mineral and chemical compositions of both the shales and the basalt suggest water-rock interactions subsequent to the intrusion with precipitation of palagonite and renewed but discrete deposition of carbonate. A pencil cleavage developed in the shales during the dike emplacement probably favored water circulation along the contact. Strontium isotopic data suggest that the fluids of probable meteoric origin, reacted with Bathonian and Bajocian limestones before entering the underlying Toarcian shales. By analogy with deep geological radioactive waste repositories, the results report discrete mineralogical variations of the clays when subjected to temperatures of 100-150 deg. C that are expected in deep storage conditions. Beyond 150 deg. C, significant mineralogical changes may alter the physical and

  14. Nature of Atmospheric Aerosols over the Desert Areas in the Asian Continent: Chemical State and Number Concentration of Particles Measured at Dunhuang, China

    International Nuclear Information System (INIS)

    Iwasaka, Y.; Shi, G.-Y.; Shen, Z.; Kim, Y. S.; Trochkine, D.; Matsuki, A.; Zhang, D.; Shibata, T.; Nagatani, M.; Nakata, H.

    2003-01-01

    Measurements of aerosol were made in August and October 2001, and January 2002, at Dunhuang, China (40 o 00'N, 94 o 30'E), to understand the nature of atmospheric particles over the desert areas in the Asian continent. Balloon-borne measurements with an optical particle counter suggested that particle size and concentration had a noticeable peak in size range of super micron in not only the boundary mixing layer but also the free troposphere. Thickness of the boundary mixing layer, from distributions of particle concentration, was about 4 km in summer (17 August 2001), about2.5 km in fall (17 October 2001), and about 3 km in winter (11 January 2002), which suggest active mixing of particles near the boundary in summer. Number-size distribution of particle showed a noticeable peak in the super micron particles size range in the mixing boundary layer: 0.4-2 particles cm -3 at diameter>1.2 μm in summer, 0.05-4 particles cm -3 at diameter >1.2 μm in fall, and 0.1-5 particles cm -3 at diameter>1.2 μm in winter. In winter strong inversion of atmospheric temperature was found in the height range from the boundary to about 3 km and vertical distribution of particle concentration well corresponded with the temperature distribution. Chemical elements of individual aerosols, which were collected in the boundary layer atmosphere at Dunhuang (18 October 2001) were analyzed with an electron microscope equipped with EDX. Those single particle analysis suggested that most of the particles with supermicron size were soil particles, and those particles had little sulfate on its surface. This is a very important different point,comparing with the chemical state of soil particles, which were transported from the desert area of China to Japan, and showed frequently the existence of sulfate on the particle surface. Therefore, it is strongly suggested that dust particles can be chemically modified during their long-range transport from desert areas to Japan

  15. Musculoskeletal management of a patient with a history of chronic ankle sprains: identifying rupture of peroneal brevis and peroneal longus with diagnostic ultrasonography.

    Science.gov (United States)

    Bruin, Dick B; von Piekartz, Harry

    2014-09-01

    The purpose of this case report is to describe the use of mobilization and eccentric exercise training for a patient with ankle pain and a history of chronic ankle sprains and discuss the course of diagnostic decision making when the patient did not respond to care. A 48-year-old police officer who had sustained multiple ankle sprains throughout his life presented with pain and restriction in his ability to walk, run, and work. The Global Rating of Change Scale score was - 6, the Numeric Pain Rating Scale score was 7/10, and the Lower Extremity Functional Scale score was - 33. Palpation of the peroneus longus and brevis muscles and inversion with overpressure reproduced the chief concern (Numeric Pain Rating Scale 7/10). The patient was initially diagnosed with chronic peroneal tendinopathy. Treatment included lateral translation mobilization of the talocrural joint combined with eccentric exercise using an elastic band for the peroneal muscles. The patient reported improvement in pain and function during the course of intervention but not as rapidly as expected. Therefore, follow-up ultrasonographic imaging and radiography were performed. These studies revealed partial rupture of the peroneal brevis muscle and total rupture of the peroneal longus muscle. A patient with long-term concerns of the foot complex with a diagnosis of peroneal tendinopathy showed slight improvement with eccentric exercises combined with manual therapy of the talocrural joint. After a course of treatment but minimal response, a diagnosis of tendon rupture was confirmed with diagnostic ultrasonography. Clinicians should be aware that when injuries do not improve with care, tendon rupture should be considered.

  16. A harmful algal bloom of Karenia brevis in the northeastern Gulf of Mexico as revealed by MODIS and VIIRS: a comparison.

    Science.gov (United States)

    Hu, Chuanmin; Barnes, Brian B; Qi, Lin; Corcoran, Alina A

    2015-01-28

    The most recent Visible Infrared Imager Radiometer Suite (VIIRS) is not equipped with a spectral band to detect solar-stimulated phytoplankton fluorescence. The lack of such a band may affect the ability of VIIRS to detect and quantify harmful algal blooms (HABs) in coastal waters rich in colored dissolved organic matter (CDOM) because of the overlap of CDOM and chlorophyll absorption within the blue-green spectrum. A recent HAB dominated by the toxin-producing dinoflagellate Karenia brevis in the northeastern Gulf of Mexico, offshore of Florida's Big Bend region, allowed for comparison of the capacities of VIIRS and Moderate Resolution Imaging Spectroradiometer (MODIS) to detect blooms in CDOM-rich waters. Both VIIRS and MODIS showed general consistency in mapping the CDOM-rich dark water, which measured a maximum area of 8900 km2 by mid-July 2014. However, within the dark water, only MODIS allowed detection of bloom patches-as indicated by high normalized fluorescence line height (nFLH). Field surveys between late July and mid-September confirmed Karenia brevis at bloom abundances up to 20 million cells·L(-1) within these patches. The bloom patches were well captured by the MODIS nFLH images, but not by the default chlorophyll a concentration (Chla) images from either MODIS or VIIRS. Spectral analysis showed that VIIRS could not discriminate these high-phytoplankton water patches within the dark water due to its lack of fluorescence band. Such a deficiency may be overcome with new algorithms or future satellite missions such as the U.S. NASA's Pre-Aerosol-Clouds-Ecology mission and the European Space Agency's Sentinel-3 mission.

  17. Radiotracer study of the adsorption of Fe(III), Cr(III) and Cd(II) on natural and chemically modified Slovak zeolite

    International Nuclear Information System (INIS)

    Foeldesova, M.; Dillinger, P.; Lukac, P.

    1998-01-01

    In order to minimize the contamination of environment with metals in ionic form the more types of natural and chemically modified zeolites were examined to their uptake of Fe(III), Cr(III) and Cd(II) from water solutions by batch radio-exchange equilibration method. In this study was used zeolitic tuff from deposit Nizny Hrabovec (content of clinoptilolite 50-70%) with the grain size from 1.2 to 2.2 mm. The granules of zeolite were modified with the following NaOH solutions: ).5, 1, 2 and 4 mol.l -1 at 80 grad C for 4 hours. The sorption of Fe, Cr and Cd ions on all types of zeolites was studied by radio-exchange method and the sorption of Fe and Cr also flame atomic absorption method. From sorption curves the sorption coefficients were calculated. The results obtained in this work show that zeolites modified with NaOH solution are suitable for adsorption of Fe(III), Cr(III) and Cd(II) from underwater, waste water, feed water and coolant water from nuclear plants. The adsorbed zeolites can be solidified by conventional way

  18. Chemical Compositions of the Peel Essential Oil of Citrus aurantium and its Natural Larvicidal Activity against the Malaria Vector Anopheles stephensi (Diptera: Culicidae in Comparison with Citrus paradisi

    Directory of Open Access Journals (Sweden)

    Alireza Sanei-Dehkordi

    2016-10-01

    Full Text Available Background: Recently, essential oils and extracts derived from plants have received much interest as potential bioactive agents against mosquito vectors.Methods: The essential oils extract from fresh peel of ripe fruit of Citrus aurantium and Citrus paradisi were tested against mosquito vector Anopheles stephensi (Diptera: Culicidae under laboratory condition. Then chemical com­position of the essential oil of C. aurantium was analyzed using gas chromatography-mass spectrometry (GC–MS.Results: The essential oils obtained from C. aurantium, and C. paradisi showed good larviciding effect against An. stephensi with LC50 values 31.20 ppm and 35.71 ppm respectively. Clear dose response relationships were established with the highest dose of 80 ppm plant extract evoking almost 100% mortality. Twenty-one (98.62% constituents in the leaf oil were identified. The main constituent of the leaf oil was Dl-limonene (94.81.Conclusion: The results obtained from this study suggest that the limonene of peel essential oil of C. aurantium is promising as larvicide against An. stephensi larvae and could be useful in the search for new natural larvicidal compounds.

  19. Relation between crystallinity and chemical nature of surface on wettability: A study on pulsed laser deposited TiO2 thin films

    International Nuclear Information System (INIS)

    Shirolkar, Mandar M.; Phase, Deodatta; Sathe, Vasant; Choudhary, Ram Janay; Rodriguez-Carvajal, J.; Kulkarni, Sulabha K.

    2011-01-01

    Pure titania (TiO 2 ) polycrystalline thin films in rutile, anatase and mixed phase have been grown on amorphous glass substrates by pulsed laser deposition method at various oxygen gas pressure. Wettability investigations have been carried out on these films. Consistent with our previous report [J. Phys. D: Appl. Phys. 41, 155308 (2008)] it has been observed that for nearly same surface roughness large contact angle or superhydrophobicity is present when sample has a pure single phase and lower contact angle or hydrophobicity when mixed phases were present. Structural characterizations suggest that in addition to roughness, pure phase film surface associated with hydrophobic sites and mixed phase film surface show association of both hydrophobic and hydrophilic sites, which might be inducing specific wetting character. UV treatment induces superhydrophilicity in the films. It was observed that UV irradiation causes nonequilibrium state on the TiO 2 surface, leading to changes in the electron density, which in turn produces decrement in the crystallinity and lattice expansion. Reversible changes in the wetting state on the pure phase surfaces were observed to be faster than those on the mixed phase surfaces. We tried to establish the possible relation between crystalline phases, chemical nature of surface on reversible wettability besides the main governing parameter viz. surface roughness.

  20. Modification of chemical and conformational properties of natural organic matter by click chemistry as revealed by ESI-Orbitrap mass spectrometry.

    Science.gov (United States)

    Nebbioso, Antonio; Piccolo, Alessandro

    2015-11-01

    A click reaction is reported here for the first time as a useful technique to control the conformational stability of natural organic matter (NOM) suprastructures. Click conjugates were successfully formed between a previously butynylated NOM hydrophobic fraction and a hydrophilic polyethylene glycol (PEG)-amino chain. The click products were shown by size exclusion chromatography (HPSEC) hyphenated with Orbitrap mass spectrometry (MS) in electrospray ionization (ESI) (+), while precursors were visible in ESI (-). Despite their increase in molecular weight, HPSEC elution of click conjugates occurred after that of precursors, thus showing their departure from the NOM supramolecular association. This indicates that the click-conjugated NOM molecules were varied in their hydrophilic and cationic character and lost the capacity to accommodate in the original hydrophobic suprastructures. The most abundant product had the C16H30O5N4 formula, a click conjugate of butanoic acid, while other products were short-chained (C4-C8) linear unsaturated and hydroxylated carboxylic acids. Tandem MS revealed formation of triazole rings in clicked conjugates and their two fragmentations at the ester and the C-N alkyl-aryl bonds. The behavior of NOM molecules modified by click chemistry confirms that hydrophobicity and ionic charge of humic molecules play a pivotal role in stabilizing intermolecular forces in NOM. Moreover, the versatility of the click reaction may become useful to decorate NOM molecules with a variety of substrates, in order to alter NOM conformational and chemical properties and diversify its applications in the environment.

  1. Book of abstracts Chemical Engineering: IV All-Russian Conference on chemical engineering, All-Russian Youth Conference on chemical engineering, All-Russian school on chemical engineering for young scientists and specialists. Materials of All-Russian Symposium on chemistry and extraction engineering. Chemical-metallurgical processes of ore and secondary raw material processing. Analytical control of chemical industries, man-made and natural objects

    International Nuclear Information System (INIS)

    Zakhodyaeva, Yu.A.; Belova, V.V.

    2012-01-01

    In the given volume of abstracts of the IV All-Russian Conference on chemical engineering, All-Russian Youth Conference on chemical engineering, All-Russian school on chemical engineering for young scientists and specialists (Moscow, March 18-23, 2012) there are the abstracts of the reports concerning polymer and composite materials technology as well as catalysis in chemical engineering. The abstracts deal with state-of-the-art and future development of theoretical and experimental investigations as well as with experience in practical realization of development works in the field of chemical engineering and relative areas [ru

  2. Human exposure to unconventional natural gas development: A public health demonstration of periodic high exposure to chemical mixtures in ambient air.

    Science.gov (United States)

    Brown, David R; Lewis, Celia; Weinberger, Beth I

    2015-01-01

    Directional drilling and hydraulic fracturing of shale gas and oil bring industrial activity into close proximity to residences, schools, daycare centers and places where people spend their time. Multiple gas production sources can be sited near residences. Health care providers evaluating patient health need to know the chemicals present, the emissions from different sites and the intensity and frequency of the exposures. This research describes a hypothetical case study designed to provide a basic model that demonstrates the direct effect of weather on exposure patterns of particulate matter smaller than 2.5 microns (PM2.5) and volatile organic chemicals (VOCs). Because emissions from unconventional natural gas development (UNGD) sites are variable, a short term exposure profile is proposed that determines 6-hour assessments of emissions estimates, a time scale needed to assist physicians in the evaluation of individual exposures. The hypothetical case is based on observed conditions in shale gas development in Washington County, Pennsylvania, and on estimated emissions from facilities during gas development and production. An air exposure screening model was applied to determine the ambient concentration of VOCs and PM2.5 at different 6-hour periods of the day and night. Hourly wind speed, wind direction and cloud cover data from Pittsburgh International Airport were used to calculate the expected exposures. Fourteen months of daily observations were modeled. Higher than yearly average source terms were used to predict health impacts at periods when emissions are high. The frequency and intensity of exposures to PM2.5 and VOCs at a residence surrounded by three UNGD facilities was determined. The findings show that peak PM2.5 and VOC exposures occurred 83 times over the course of 14 months of well development. Among the stages of well development, the drilling, flaring and finishing, and gas production stages produced higher intensity exposures than the

  3. Biomass Burning and Natural Emissions in the Brazilian Amazon Rainforest: Chemical Composition and Impact on the Oxidative Capacity of the Atmosphere

    Science.gov (United States)

    dos Santos, F. C.; Longo, K.; Guenther, A. B.; Gu, D.; Kim, S.; Freitas, S.; Moreira, D. S.; Flávio, L.; Braz, R.; Brito, J.; Oram, D.; Foster, G.; Lee, J. D.

    2017-12-01

    Emitted by vegetation, isoprene (2-methyl-1,3-butadiene) is the most abundant non-methane hydrocarbons, with an annual global emission calculated ranging from 440 to 660Tg carbon, depending on the driving variables like temperature, solar radiation, LAI and PFT. The natural compounds like isoprene and terpenes present in the troposphere are about 90% and 50%, respectively, removed from the atmosphere by oxidation performed by hydroxyl radical (OH). Considering the importance of these emissions and the hydroxyl radical reaction in the atmosphere, the SAMBBA (South American Biomass Burning Analysis) experiment, which occurred during the dry season (September 2012) in the Brazilian Amazon Rainforest, provided information about the chemical composition of the atmosphere through airborne observations. Although primarily focused on biomass burning flights, the SAMBBA project carried out flights in pristine environment. In this study, we determine the ambient distribution of CO, NOx and O3, and evaluate the oxidative capacity of the Amazon rainforest in different chemical regimes, using the ratio [MVK + MACR]/[Isoprene]. Beyond that, we proposed an improvement on the formulation of indirect OH density calculation, using the photochemical aging [O3]/[CO] as a parameter. Balancing numerical modeling and direct observations, the numerical model BRAMS was coupled to MEGAN emission model to get a better result for isoprene and OH in the atmosphere, representing the observations during SAMBBA field campaign. In relation to OH estimation, we observed an improvement in the concentration values using the modified sequential reaction model, for both biomass burning regimes and background environment. We also detected a long-range transport events of O3, considering the high levels of O3 in aged plumes at high altitudes (5,500 - 6,500 m), and the detection of an O3 inflow in the Amazon basin from Africa. These findings support the importance of long-range transport events as a

  4. Pair Natural Orbital Restricted Open-Shell Configuration Interaction (PNO-ROCIS) Approach for Calculating X-ray Absorption Spectra of Large Chemical Systems.

    Science.gov (United States)

    Maganas, Dimitrios; DeBeer, Serena; Neese, Frank

    2018-02-08

    In this work, the efficiency of first-principles calculations of X-ray absorption spectra of large chemical systems is drastically improved. The approach is based on the previously developed restricted open-shell configuration interaction singles (ROCIS) method and its parametrized version, based on a density functional theory (DFT) ground-state determinant ROCIS/DFT. The combination of the ROCIS or DFT/ROCIS methods with the well-known machinery of the pair natural orbitals (PNOs) leads to the new PNO-ROCIS and PNO-ROCIS/DFT variants. The PNO-ROCIS method can deliver calculated metal K-, L-, and M-edge XAS spectra orders of magnitude faster than ROCIS while maintaining an accuracy with calculated spectral parameters better than 1% relative to the original ROCIS method (referred to as canonical ROCIS). The method is of a black box character, as it does not require any user adjustments, while it scales quadratically with the system size. It is shown that for large systems, the size of the virtual molecular orbital (MO) space is reduced by more than 90% with respect to the canonical ROCIS method. This allows one to compute the X-ray absorption spectra of a variety of large "real-life" chemical systems featuring hundreds of atoms using a first-principles wave-function-based approach. Examples chosen from the fields of bioinorganic and solid-state chemistry include the Co K-edge XAS spectrum of aquacobalamin [H 2 OCbl] + , the Fe L-edge XAS spectrum of deoxymyoglobin (DMb), the Ti L-edge XAS spectrum of rutile TiO 2 , and the Fe M-edge spectrum of α-Fe 2 O 3 hematite. In the largest calculations presented here, molecules with more than 700 atoms and cluster models with more than 50 metal centers were employed. In all the studied cases, very good to excellent agreement with experiment is obtained. It will be shown that the PNO-ROCIS method provides an unprecedented performance of wave-function-based methods in the field of computational X-ray spectroscopy.

  5. Process design of a hydrogen production plant from natural gas with CO2 capture based on a novel Ca/Cu chemical loop

    International Nuclear Information System (INIS)

    Martínez, I.; Romano, M.C.; Fernández, J.R.; Chiesa, P.; Murillo, R.; Abanades, J.C.

    2014-01-01

    Highlights: • Process design of a H 2 production plant based on a novel Ca/Cu looping process is presented. • CuO reduction with syngas provides energy for CaCO 3 calcination. • The effect of operating conditions on plant performance indexes is analysed. • Carbon capture efficiencies of around 94% are obtained. • Around 6% points of equivalent H 2 efficiency improvement on conventional reforming. - Abstract: A detailed and comprehensive design of a H 2 production plant based on a novel Ca/Cu chemical looping process is presented in this work. This H 2 production process is based on the sorption-enhanced reforming concept using natural gas together with a CaO/CaCO 3 chemical loop. A second Cu/CuO loop is incorporated to supply energy for the calcination of the CaCO 3 via the reduction of CuO with a fuel gas. A comprehensive energy integration description of the different gas streams available in the plant is provided to allow a thermodynamic assessment of the process and to highlight its advantages and drawbacks. Hydrogen equivalent efficiencies of up to 77% are feasible with this novel Ca/Cu looping process, using an active reforming catalyst based on Pt, high oxidation temperatures and moderate gas velocities in the fixed bed system, which are around 6% points above the efficiency of a reference H 2 production plant based on conventional steam reforming including CO 2 capture with MDEA. Non-converted carbon compounds in the reforming stage are removed as CO 2 in the calcination stage of the Ca/Cu looping process, which will be compressed and sent for storage. Carbon capture efficiencies of around 94% can be obtained with this Ca/Cu looping process, which are significantly higher than those obtained in the reference plant that uses MDEA absorption (around 85%). Additional advantages, such as its compact design and the use of cheaper materials compared to other commercial processes for H 2 production with CO 2 capture, confirm the potential of the Ca

  6. An expert elicitation process to project the frequency and magnitude of Florida manatee mortality events caused by red tide (Karenia brevis)

    Science.gov (United States)

    Martin, Julien; Runge, Michael C.; Flewelling, Leanne J.; Deutsch, Charles J.; Landsberg, Jan H.

    2017-11-20

    Red tides (blooms of the harmful alga Karenia brevis) are one of the major sources of mortality for the Florida manatee (Trichechus manatus latirostris), especially in southwest Florida. It has been hypothesized that the frequency and severity of red tides may increase in the future because of global climate change and other factors. To improve our ecological forecast for the effects of red tides on manatee population dynamics and long-term persistence, we conducted a formal expert judgment process to estimate probability distributions for the frequency and relative magnitude of red-tide-related manatee mortality (RTMM) events over a 100-year time horizon in three of the four regions recognized as manatee management units in Florida. This information was used to update a population viability analysis for the Florida manatee (the Core Biological Model). We convened a panel of 12 experts in manatee biology or red-tide ecology; the panel met to frame, conduct, and discuss the elicitation. Each expert provided a best estimate and plausible low and high values (bounding a confidence level of 80 percent) for each parameter in each of three regions (Northwest, Southwest, and Atlantic) of the subspecies’ range (excluding the Upper St. Johns River region) for two time periods (0−40 and 41−100 years from present). We fitted probability distributions for each parameter, time period, and expert by using these three elicited values. We aggregated the parameter estimates elicited from individual experts and fitted a parametric distribution to the aggregated results.Across regions, the experts expected the future frequency of RTMM events to be higher than historical levels, which is consistent with the hypothesis that global climate change (among other factors) may increase the frequency of red-tide blooms. The experts articulated considerable uncertainty, however, about the future frequency of RTMM events. The historical frequency of moderate and intense RTMM (combined) in

  7. Cob(I)alamin: insight into the nature of electronically excited states elucidated via quantum chemical computations and analysis of absorption, CD and MCD data.

    Science.gov (United States)

    Kornobis, Karina; Ruud, Kenneth; Kozlowski, Pawel M

    2013-02-07

    The nature of electronically excited states of the super-reduced form of vitamin B(12) (i.e., cob(I)alamin or B(12s)), a ubiquitous B(12) intermediate, was investigated by performing quantum-chemical calculations within the time-dependent density functional theory (TD-DFT) framework and by establishing their correspondence to experimental data. Using response theory, the electronic absorption (Abs), circular dichroism (CD) and magnetic CD (MCD) spectra of cob(I)alamin were simulated and directly compared with experiment. Several issues have been taken into considerations while performing the TD-DFT calculations, such as strong dependence on the applied exchange-correlation (XC) functional or structural simplification imposed on the cob(I)alamin. In addition, the low-lying transitions were also validated by performing CASSCF/MC-XQDPT2 calculations. By comparing computational results with existing experimental data a new level of understanding of electronic excitations has been established at the molecular level. The present study extends and confirms conclusions reached for other cobalamins. In particular, the better performance of the BP86 functional, rather than hybrid-type, was observed in terms of the excitations associated with both Co d and corrin π localized transitions. In addition, the lowest energy band was associated with multiple metal-to-ligand charge transfer excitations as opposed to the commonly assumed view of a single π → π* transition followed by vibrational progression. Finally, the use of the full cob(I)alamin structure, instead of simplified molecular models, shed new light on the spectral analyses of cobalamin systems and revealed new challenges of this approach related to long-range charge transfer excitations involving side chains.

  8. Dissolved Organic In Natural and Polluted Waters: Methodology and Results of Running Control of Chemical Oxygen Demand (cod) For The Inland and Marine Aquatic System

    Science.gov (United States)

    Melentyev, K. V.; Worontsov, A. M.

    Current control of dissolved organic matter in natural and waste waters is the definition traditionally of chemical oxygen demand (COD) -- one of the basic parameters of quality of water. According to the International Standard (ISO 6060), it requires not less than one hour, while in many cases the operative information about amount of dissolved organic matter in aquatic environments have importance for prevention of an emergency. The standard method is applicable to waters with meaning of COD above 30 mg O2/l and, as the chloride ion prevents, it could be difficult for assessment of organic matter in sea water. Besides it is based on dichromate oxidation of the sum of organic substances in strong acid conditions at the presence of silver and mercury, that resulted in formation toxic pollutants. Till now attempts of automation of the COD definition in aquatic system were limited, basically, to duplication of the technology submitted the above standard (automatic COD analyzers "SERES Co."-- France, or "Tsvet Co." - Russia). The system of ozone-chemiluminescence automatic control of organic matter in water (CS COD) is offered and designed. Its based on the ozone oxidation of these substances in flowing water system and measurement arising from luminescent effects. CS COD works in real time. An instrument uses for reaction the atmospheric air, doesn't require fill of reagents and doesn't make new toxic pollutants. The system was tested in laboratory, and biochemical control of organic matter in water samples gathered from the river Neva and other polluted inland water areas and basins in St. Petersburg region was fulfilled (distilled water was used as "zero" media). The results of systematization of these measurements are presented. The new special ozone generator and flowing reactor for real-time running control of different waters in natural conditions were developed, and several series of large - scale field experiments onboard research ship were provided

  9. Criopreservação do sêmen de Prochilodus brevis: meios de congelação e taxas de descongelação

    Directory of Open Access Journals (Sweden)

    Larissa Teixeira Nunes

    2016-06-01

    Full Text Available O Prochilodus brevis é um peixe reofílico, importante componente do ecossistema fluvial e apreciado na culinária nordestina. No entanto, ações antrópicas têm ameaçado sua sobrevivência. Desta forma, surge, nos pesquisadores, o interesse no desenvolvimento de protocolos de conservação do material genético, como a criopreservação seminal. Logo, a determinação do meio de congelação e da taxa de descongelação adequados, são passos fundamentais que possibilitarão a utilização dessa biotecnologia na produção de curimatã comum, reduzindo os riscos à sua sobrevivência. Portanto, o objetivo desse trabalho foi avaliar o efeito de diferentes meios de congelação e taxas de descongelação sobre a qualidade do sêmen criopreservado de P. brevis. Para isso, 18 horas antes da coleta de sêmen, os machos receberam dose única de extrato hipofisário de carpa. Cada animal foi sedado com solução à base de eugenol e o sêmen foi coletado. As amostras foram diluídas em quatro meios de congelação (5% Glicose + Metilglicol 10%; 5% Glicose + DMSO 10%; 0,9% NaCl + Metilglicol 10%; 0,9% NaCl + DMSO 10% envasadas em palhetas de 0,25 mL e congeladas em vapor de nitrogênio líquido. O sêmen foi descongelado após sete dias em três taxas de descongelação: 25 °C 30 s-1; 30 °C 16 s-1; 40 °C 12 s-1. Foram feitas as análises de motilidade, vitalidade e morfologia com auxílio de sistema automatizado de análise seminal (CASA. As características do sêmen in natura assemelharam-se, em sua maioria, às encontradas na literatura. Para os parâmetros analisados, o sêmen in natura apresentou qualidade seminal superior a todos os tratamentos com o sêmen criopreservado (p 0,05. Para o sêmen criopreservado, os maiores índices foram alcançados quando se utilizou DMSO e as taxas de descongelação de 30 °C 16 s-1 ou 40 °C 12 s-1. Quanto à análise morfológica, a maior porcentagem de espermatozoides normais foi obtida utilizando as

  10. Expression of Genes Involved in Bacteriocin Production and Self-Resistance in Lactobacillus brevis 174A Is Mediated by Two Regulatory Proteins.

    Science.gov (United States)

    Noda, Masafumi; Miyauchi, Rumi; Danshiitsoodol, Narandalai; Matoba, Yasuyuki; Kumagai, Takanori; Sugiyama, Masanori

    2018-04-01

    We have previously shown that the lactic acid bacterium Lactobacillus brevis 174A, isolated from Citrus iyo fruit, produces a bacteriocin designated brevicin 174A, which is comprised of two antibacterial polypeptides (designated brevicins 174A-β and 174A-γ). We have also found a gene cluster, composed of eight open reading frames (ORFs), that contains genes for the biosynthesis of brevicin 174A, self-resistance to its own bacteriocin, and two transcriptional regulatory proteins. Some lactic acid bacterial strains have a system to start the production of bacteriocin at an adequate stage of growth. Generally, the system consists of a membrane-bound histidine protein kinase (HPK) that senses a specific environmental stimulus and a corresponding response regulator (RR) that mediates the cellular response. We have previously shown that although the HPK- and RR-encoding genes are not found on the brevicin 174A biosynthetic gene cluster in the 174A strain, two putative regulatory genes, designated breD and breG , are in the gene cluster. In the present study, we demonstrate that the expression of brevicin 174A production and self-resistance is positively controlled by two transcriptional regulatory proteins, designated BreD and BreG. BreD is expressed together with BreE as the self-resistance determinant of L. brevis 174A. DNase I footprinting analysis and a promoter assay demonstrated that BreD binds to the breED promoter as a positive autoregulator. The present study also demonstrates that BreG, carrying a transmembrane domain, binds to the common promoter of breB and breC , encoding brevicins 174A-β and 174A-γ, respectively, for positive regulation. IMPORTANCE The problem of the appearance of bacteria that are resistant to practical antibiotics and the increasing demand for safe foods have increased interest in replacing conventional antibiotics with bacteriocin produced by the lactic acid bacteria. This antibacterial substance can inhibit the growth of pathogenic

  11. Effect of incorporation of natural chemicals in water ice-glazing on freshness and shelf-life of Pacific saury (Cololabis saira) during -18 °C frozen storage.

    Science.gov (United States)

    Luo, Haibo; Wang, Weihua; Chen, Wei; Tang, Haiqing; Jiang, Li; Yu, Zhifang

    2017-12-14

    Microbial spoilage and lipid oxidation are two major factors causing freshness deterioration of Pacific saury (Cololabis saira) during frozen storage. To provide a remedy, the effects of several natural chemicals incorporated alone or in combination in traditional water ice-glazing on the freshness and shelf-life of Pacific saury during frozen storage at -18 °C were investigated. Pacific sauries were subjected to individual quick freezing followed immediately by dipping into cold tap water (control) or solutions containing nisin, chitosan, phytic acid (single-factor experiment) or their combinations ((L 9 (3 4 ) orthogonal experiment) for 10 s at 1 °C and then packaged in polypropylene bags before frozen storage at -18 °C. The storage duration tested was up to 12 months. All ice-glazing treatments with individual chemicals could significantly (P shelf-life of Pacific saury could be extended up to 12 months at -18 °C. The study indicated that the combination treatment with natural chemicals could be commercially utilized to maintain the freshness and prolong the shelf-life of Pacific saury. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  12. Physico-chemical characterization of natural fermentation process of Conservolea and Kalamàta table olives and developement of a protocol for the pre-selection of fermentation starters.

    Science.gov (United States)

    Bleve, Gianluca; Tufariello, Maria; Durante, Miriana; Grieco, Francesco; Ramires, Francesca Anna; Mita, Giovanni; Tasioula-Margari, Maria; Logrieco, Antonio Francesco

    2015-04-01

    Table olives are one of the most important traditional fermented vegetables in Europe and their world consumption is constantly increasing. Conservolea and Kalamàta are the most important table olives Greek varieties. In the Greek system, the final product is obtained by spontaneous fermentations, without any chemical debittering treatment. This natural fermentation process is not predictable and strongly influenced by the physical-chemical conditions and by the presence of microorganisms contaminating the olives. Natural fermentations of Conservolea and Kalamàta cultivars black olives were studied in order to determine microbiological, biochemical and chemical evolution during the process. Following the process conditions generally used by producers, in both cultivars, yeasts were detected throughout the fermentation, whereas lactic acid bacteria (LAB) appeared in the last staged of the process. A new optimized specific protocol was developed to select autochthonous yeast and LAB isolates that can be good candidates as starters. These microorganisms were pre-selected for their ability to adapt to model brines, to have beta-glucosidase activity, not to produce biogenic amines. Chemical compounds deriving by microbiological activities and associated to the three different phases (30, 90 and 180 days) of the fermentation process were identified and were proposed as chemical descriptors to follow the fermentation progress. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Multi-Sensor Approach for the Monitoring of Halitosis Treatment via Lactobacillus brevis (CD2—Containing Lozenges—A Randomized, Double-Blind Placebo-Controlled Clinical Trial

    Directory of Open Access Journals (Sweden)

    Enrico Marchetti

    2015-08-01

    Full Text Available The aim of this randomized clinical trial was to evaluate whether a recently described multi-sensor approach called BIONOTE® is accurate enough to verify the efficacy of treatment of patients with halitosis. A treatment with Lactobacillus brevis (CD2–containing lozenges, compared with placebo was tested. The BIONOTE® was compared with traditional techniques used to detect halitosis: OralChroma™ and two calibrated odor judges enrolled for the organoleptic assessments. Twenty patients (10 treated and 10 placebo, suffering from active phase halitosis were included in the study. Treatment consisted of Lactobacillus brevis (CD2—containing lozenges or placebo, 4 tablets/day for 14 days. t0 was before the beginning of the study; t1 was day 7 and t2 was day 14. The effectiveness of treatment was assessed through: (1 Rosenberg score; (2 Winkel tongue coating index (WTCI anterior and posterior; (2 OralChroma™; (3 the new developed multi-sensor approach, called BIONOTE® (test technique. Only the WTCI anterior revealed statistically significant changes between t0 and t2 data (p = 0.014 in the treated group. Except for the WTCI anterior, all diagnostic methods revealed the lack of effectiveness for halitosis of a 14-days treatment with Lactobacillus brevis (CD2–containing lozenges. The BIONOTE® multisensor system seems accurate in addition to OralChroma™ to assess the initial condition of halitosis and its mitigation during treatment.

  14. Cultivated strains of Agaricus bisporus and A.brasiliensis: chemical characterization and evaluation of antioxidant and antimicrobial properties for the final healthy product – natural preservatives in yoghurt

    NARCIS (Netherlands)

    Stojkovic, D.S.; Reis, F.S.; Glamoclija, J.; Ciric, A.; Barros, L.; Griensven, van L.J.L.D.; Ferreira, I.C.F.R.; Sokovic, M.

    2014-01-01

    Agaricus bisporus (J. E. Lange) Emil J. Imbach and Agaricus brasiliensis Wasser, M. Didukh, Amazonas & Stamets are edible mushrooms. We chemically characterized these mushrooms for nutritional value, hydrophilic and lipophilic compounds. The antioxidant and antimicrobial activities of methanolic

  15. The Elbow-EpiTrainer: a method of delivering graded resistance to the extensor carpi radialis brevis. Effectiveness of a prototype device in a healthy population.

    Science.gov (United States)

    Navsaria, Rishi; Ryder, Dionne M; Lewis, Jeremy S; Alexander, Caroline M

    2015-03-01

    Tennis elbow or lateral epicondylopathy (LE) is experienced as the lateral elbow has a reported prevalence of 1.3%, with symptoms lasting up to 18 months. LE is most commonly attributed to tendinopathy involving the extensor carpi radialis brevis (ECRB) tendon. The aim of tendinopathy management is to alleviate symptoms and restore function that initially involves relative rest followed by progressive therapeutic exercise. To assess the effectiveness of two prototype exercises using commonly available clinical equipment to progressively increase resistance and activity of the ECRB. Eighteen healthy participants undertook two exercise progressions. Surface electromyography was used to record ECRB activity during the two progressions, involving eccentric exercises of the wrist extensors and elbow pronation exercises using a prototype device. The two progressions were assessed for their linearity of progression using repeated ANOVA and linear regression analysis. Five participants repeated the study to assess reliability. The exercise progressions led to an increase in ECRB electromyographic (EMG) activity (p0.7) between the first and second tests for five participants. Manipulation of resistance and leverage with the prototype exercises was effective in creating significant increases of ECRB normalised EMG activity in a linear manner that may, with future research, become useful to clinicians treating LE. In addition, between trial reliability for the device to generate a consistent load was acceptable. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  16. Preliminary observations on high energy phosphates and metabolic pathway and transporter potentials in extensor carpi radialis brevis and trapezius muscles of women with work-related myalgia.

    Science.gov (United States)

    Green, Howard J; Ranney, Don; Burnett, Margaret; Galvin, Patti; Kyle, Natasha; Lounsbury, David; Ouyang, Jing; Smith, Ian C; Stewart, Riley; Tick, Heather; Tupling, A Russell

    2014-11-01

    This study compared both the extensor carpi radialis brevis (ECRB) and the trapezius (TRAP) muscles of women with work-related myalgia (WRM) with healthy controls (CON) to determine whether abnormalities existed in cellular energy status and the potentials of the various metabolic pathways and segments involved in energy production and substrate transport. For both the ECRB (CON, n = 6-9; WRM, n = 13) and the TRAP (CON, n = 6-7; WRM, n = 10), no differences (P > 0.05) were found for the concentrations (in millimoles per kilogram of dry mass) of ATP, PCr, lactate, and glycogen. Similarly, with one exception, the maximal activities (in moles per milligram of protein per hour) of mitochondrial enzymes representative of the citric acid cycle (CAC), the electron transport chain (ETC), and β-oxidation, as well as the cytosolic enzymes involved in high energy phosphate transfer, glycogenolysis, glycolysis, lactate oxidation, and glucose phosphorylation were not different (P > 0.05). The glucose transporters GLUT1 and GLUT4, and the monocarboxylate transporters MCT1 and MCT4, were also normal in WRM. It is concluded that, in general, abnormalities in the resting energy and substrate state, the potential of the different metabolic pathways and segments, as well as the glucose and monocarboxylate transporters do not appear to be involved in the cellular pathophysiology of WRM.

  17. A Comparison of Radiofrequency-Based Microtenotomy and Arthroscopic Release of the Extensor Carpi Radialis Brevis Tendon in Recalcitrant Lateral Epicondylitis: A Prospective Randomized Controlled Study.

    Science.gov (United States)

    Lee, Jae-Hoo; Park, In; Hyun, Hwan-Sub; Shin, Sang-Jin

    2018-01-20

    To compare the clinical effects of radiofrequency (RF)-based microtenotomy and arthroscopic release of the extensor carpi radialis brevis (ECRB) tendon in patients with recalcitrant lateral epicondylitis through a prospective randomized controlled study. A total of 46 patients were randomly assigned to receive arthroscopic release (group A, 24 patients) or RF-based microtenotomy (group B, 22 patients). The visual analog scale (VAS) score for pain, flexion-extension arc, operation time, Disabilities of the Arm, Shoulder, and Hand questionnaire (DASH), Mayo Elbow Performance Score (MEPS), and grip power of groups A and B were compared during the recovery phases for up to 2 postoperative years. Both groups showed statistically significant functional improvement compared with their preoperative grip strength and DASH, VAS, and MEPS scores at 2 years after surgery (P lateral epicondylitis provided clinical outcomes comparable with those from arthroscopic release of ECRB tendon during the recovery phase. RF-based microtenotomy is considered as one of the surgical procedures for treating recalcitrant lateral epicondylitis, with the advantages of reliable elbow functional restoration and significantly shorter operation time. Level I, prospective randomized trial. Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  18. Effect of heat-killed Lactobacillus brevis SBC8803 on cutaneous arterial sympathetic nerve activity, cutaneous blood flow and transepidermal water loss in rats.

    Science.gov (United States)

    Horii, Y; Kaneda, H; Fujisaki, Y; Fuyuki, R; Nakakita, Y; Shigyo, T; Nagai, K

    2014-05-01

    To evaluate the efficacy of the effects of heat-killed Lactobacillus brevis SBC8803 (HK-SBC8803) on the standard physiological markers of skin health of cutaneous arterial sympathetic nerve activity (CASNA), cutaneous blood flow and transepidermal water loss (TEWL) and to determine whether SBC8803 targets serotonin 5-HT3 receptors in rats. A set of three experiments were conducted to examine the effects of SBC8803 on CASNA, cutaneous blood flow and TEWL using Wistar and hairless rats. Two additional experiments further attempted to determine whether HK-SBC8803 was targeting the serotonin 5-HT3 receptors by pretreatment with the 5-HT3 antagonist granisetron. Administration of HK-SBC8803 in the first three experiments caused marked inhibition of CASNA and significant elevation of cutaneous blood flow under urethane anaesthesia as well as significant decrease in TEWL on the dorsal skin of conscious hairless rats. Pretreatment with granisetron decreased the effects of HK-SBC8803 on CASNA and cutaneous blood flow. These findings suggest that HK-SBC8803 reduces CASNA, increases cutaneous blood flow and decreases TEWL and that 5-HT3 receptors may be involved in CASNA and cutaneous blood flow responses. HK-SBC8803 could be a useful substance in the treatment/prevention of skin problems, specifically chapped or dry skin. © 2014 The Society for Applied Microbiology.

  19. Satellite retrievals of Karenia brevis harmful algal blooms in the West Florida shelf using neural networks and impacts of temporal variabilities

    Science.gov (United States)

    El-Habashi, Ahmed; Duran, Claudia M.; Lovko, Vincent; Tomlinson, Michelle C.; Stumpf, Richard P.; Ahmed, Sam

    2017-07-01

    We apply a neural network (NN) technique to detect/track Karenia brevis harmful algal blooms (KB HABs) plaguing West Florida shelf (WFS) coasts from Visible-Infrared Imaging Radiometer Suite (VIIRS) satellite observations. Previously KB HABs detection primarily relied on the Moderate Resolution Imaging Spectroradiometer Aqua (MODIS-A) satellite, depending on its remote sensing reflectance signal at the 678-nm chlorophyll fluorescence band (Rrs678) needed for normalized fluorescence height and related red band difference retrieval algorithms. VIIRS, MODIS-A's successor, does not have a 678-nm channel. Instead, our NN uses Rrs at 486-, 551-, and 671-nm VIIRS channels to retrieve phytoplankton absorption at 443 nm (a). The retrieved a images are next filtered by applying limits, defined by (i) low Rrs551-nm backscatter and (ii) a minimum a value associated with KB HABs. The filtered residual images are then converted to show chlorophyll-a concentrations [Chla] and KB cell counts. VIIRS retrievals using our NN and five other retrieval algorithms were compared and evaluated against numerous in situ measurements made over the four-year 2012 to 2016 period, for which VIIRS data are available. These comparisons confirm the viability and higher retrieval accuracies of the NN technique, when combined with the filtering constraints, for effective detection of KB HABs. Analysis of these results as well as sequential satellite observations and recent field measurements underline the importance of short-term temporal variabilities on retrieval accuracies.

  20. Siderophores of Stenotrophomonas maltophilia: detection and determination of their chemical nature Sideróforos de Stenotrophomonas maltophilia: detección y determinación de su naturaleza química

    OpenAIRE

    Carlos A. García; Beatriz Passerini De Rossi; Eliana Alcaraz; Carlos Vay; Mirta Franco

    2012-01-01

    Stenotrophomonas maltophilia is an emerging nosocomial pathogen. Despite the broad spectrum of syndromes associated with S. maltophilia infections, little is known about its virulence factors, including siderophore production. The aims of this work were to detect S. maltophilia siderophores and to determine their chemical nature. We studied 31 S. maltophilia isolates from device-associated infections, recovered over the period 2006-2011 at Hospital de Clínicas José de San Martin, Buenos Aires...

  1. Radiological assessment and chemical treatment of contaminated soil with naturally occurring radioactive materials ''NORM'' by leaching with different solvents and their reuse

    International Nuclear Information System (INIS)

    Nafae, T.M.

    2015-01-01

    Contaminated soil with naturally occurring radioactive material NORM is produced from uncontrolled disposal of oil field produced water in the surrounding environment or scale and sludge produced from clean-up operation system is considered as a real big problem in Iraq which causes exposure and contamination of worker and environment. The present work aims to treat the contaminated soil with NORM in order to minimize the volume of radioactive waste and to reduce the risk of radiation to the allowable limits. Samples of representative contaminated soil from Al-Rumaila oil field in Al-Basra governorate was prepared for analysis and leaching tests Gamma spectrometer with extended range low-level coaxial High Purity Germanium (HPGe) detector with high resolution (2.1 keV at 1332 keV) and 50% relative efficiency was utilized to measured all samples. Two techniques were tested, mechanical separation and chemical treatment. Screening of contaminated soil was performed to evaluate the feasibility of particle size separation. The fractions obtained varied between 75micro meter Greek Small Letter (200 mesh) to 300μm (48 mesh).The results show that the largest weight percent in fine particle size ( -75, -125+75, -250+125) μm is 73.9% and all radium isotopes are concentrated in 37.5μm particle size while small fluctuations are observed in the other particle size cuts.In the chemical treatment, many factors were studied to determine the best conditions for leaching process; type of solvent (HNO 3 , HCl, C 2 H 4 O 2 , H 2 SO 4 , NaOH, H 2 O), acid concentration (3, 5, 7, 10 M) , liquid to solid ratio(L:S) (3, 5, 7, 9, 18, 30 ml/g), temperature ( 28, 40, 60,78°C), and number of stages. Results indicate that only small portions of radium are present on the surface of soil particles, while most radium located within soil particles. Concentrated nitric acid (5M) was found to be the most effective solvent using two stages with L:S ratio of 9 ml/g at a temperature of 60 Co. At

  2. Role of natural gas in the chemical-process industry: Implications for the future. Volume 1. Final report, January 1989-June 1990

    Energy Technology Data Exchange (ETDEWEB)

    Kesler, M.L.; Ex, B.

    1990-12-01

    The study examines the historical and current use of natural gas in SIC 28 and predicts the future of natural gas consumption and the factors that can cause gas usage to change over the period of the GRI Baseline. The study assesses how future economic, technological, and regulatory events may effect the use of natural gas in SIC 28. The information provides an information data base to enhance GRI's R and D planning efforts by highlighting emerging issues and identifying areas whereby gas-based technology can seize advantage of an opportunity or mitigate a risk.

  3. Role of natural gas in the chemical process industry: Implications for the future. Volume 2, appendices. Final report, January 1989-June 1990

    Energy Technology Data Exchange (ETDEWEB)

    Kesler, M.L.; Ex, B.

    1990-12-01

    The study examines the historical and current use of natural gas in SIC 28 and predicts the future of natural gas consumption and the factors that can cause gas usage to change over the period of the GRI Baseline. The study assesses how future economic, technological, and regulatory events may effect the use of natural gas in SIC 28. The information provides an information data base to enhance GRI's R and D planning efforts by highlighting emerging issues and identifying areas whereby gas-based technology can seize advantage of an opportunity or mitigate a risk.

  4. Effect of natural Bayah zeolite particle size reduction to physico-chemical properties and absortion against potassium permanganate (KMnO4)

    Science.gov (United States)

    Widayanti, Siti Mariana; Syamsu, Khaswar; Warsiki, Endang; Yuliani, Sri

    2016-02-01

    Recently, researches on nanotechnology have been developed very rapid, as well as the utilization of nano-zeolites. Nano-sized material has several advantages which are expanding absorptive surfaces so it will enhance the material absorption and shorten the absorption time. Zeolite as a KMnO4 binder, has been widely recognized for its ability to extend the shelf life of vegetables and fruits. This study was conducted to determine zeolites physico-chemical characters from different particle size and the effect on KMnO4 absorption. Potassium permanganate (KMnO4) is a strong oxidizer for reducing the quantity of ethylene in storage process of fresh horticultural products. The treatment consisted of (1) different length of milling time (10, 20, 30, 40, and 60 minutes) and (2) the duration of chemical activation with 1 N KOH solution. Physical and chemical characters of zeolite were analyzed using BET, PSA, XRD and SEM. The research design was randomized design. The result implied that milling time was significantly affecting the zeolite particle size, material surface area, and the size of pore diameter and volume. Milling treatment for 40 minutes produced higher zeolite surface area and pore volume than other treatments. While the duration of chemical activation using 1 N KOH solution gives different effect on zeolite absorption to KMnO4 solution. Milling time for 60 minutes and activated for 48 hours has higher initial adsorption than other treatments.

  5. The Nature of the Interplay among Components of Pedagogical Content Knowledge in Reaction Rate and Chemical Equilibrium Topics of Novice and Experienced Chemistry Teachers

    Science.gov (United States)

    Akin, Fatma Nur; Uzuntiryaki-Kondakci, Esen

    2018-01-01

    We examined the interactions among pedagogical content knowledge (PCK) components of novice and experienced chemistry teachers in teaching reaction rate and chemical equilibrium topics in this qualitative multiple-case design study. For this aim, three chemistry teachers who had different levels of teaching experience in chemistry teaching were…

  6. Chemical Peels

    Science.gov (United States)

    ... care Kids’ zone Video library Find a dermatologist Chemical peels Overview Chemical peels: Overview Also called chemexfoliation , derma peeling Do ... Overview Chemical peels: FAQs Chemical peels: Preparation FAQs Chemical peels: FAQs To help you decide whether this ...

  7. Mineralogical, chemical and K-Ar isotopic changes in Kreyenhagen Shale whole rocks and <2 µm clay fractions during natural burial and hydrous-pyrolysis experimental maturation

    Science.gov (United States)

    Clauer, Norbert; Lewan, Michael D.; Dolan, Michael P.; Chaudhuri, Sambhudas; Curtis, John B.

    2014-01-01

    Progressive maturation of the Eocene Kreyenhagen Shale from the San Joaquin Basin of California was studied by combining mineralogical and chemical analyses with K–Ar dating of whole rocks and sequence, indicating that there is no detectable variation in the crystallo-chemical organization of the K-bearing alumino-silicates with depth. No supply of K from outside of the rock volumes occurred, which indicates a closed-system behavior for it. Conversely, the content of the total organic carbon (TOC) content decreases significantly with burial, based on the progressive increasing Al/TOC ratio of the whole rocks. The initial varied mineralogy and chemistry of the rocks and their <2 μm fractions resulting from differences in detrital sources and depositional settings give scattered results that homogenize progressively during burial due to increased authigenesis, and concomitant increased alteration of the detrital material.

  8. Cultivated strains of Agaricus bisporus and A. brasiliensis: chemical characterization and evaluation of antioxidant and antimicrobial properties for final healthy product - natural preservatives in yoghurt

    OpenAIRE

    Stojković, Dejan; Reis, Filipa S.; Glamočlija, Jasmina; Ćirić, Ana; Barros, Lillian; Van Griensven, Leo J.L.D.; Ferreira, Isabel C.F.R.; Soković, Marina

    2014-01-01

    Agaricus bisporus (J. E. Lange) Emil J. Imbach and Agaricus brasiliensis Wasser, M. Didukh, Amazonas & Stamets are edible mushrooms. We chemically characterized these mushrooms for nutritional value, hydrophilic and lipophilic compounds. The antioxidant and antimicrobial activities of methanolic and ethanolic extracts were assessed. Hepatotoxicity was also evaluated. The ethanolic extract of both species was tested for inhibition of Listeria monocytogenes growth in yoghurt. Both s...

  9. Enhancement of γ-aminobutyric acid production in recombinant Corynebacterium glutamicum by co-expressing two glutamate decarboxylase genes from Lactobacillus brevis.

    Science.gov (United States)

    Shi, Feng; Jiang, Junjun; Li, Yongfu; Li, Youxin; Xie, Yilong

    2013-11-01

    γ-Aminobutyric acid (GABA), a non-protein amino acid, is a bioactive component in the food, feed and pharmaceutical fields. To establish an effective single-step production system for GABA, a recombinant Corynebacterium glutamicum strain co-expressing two glutamate decarboxylase (GAD) genes (gadB1 and gadB2) derived from Lactobacillus brevis Lb85 was constructed. Compared with the GABA production of the gadB1 or gadB2 single-expressing strains, GABA production by the gadB1-gadB2 co-expressing strain increased more than twofold. By optimising urea supplementation, the total production of L-glutamate and GABA increased from 22.57 ± 1.24 to 30.18 ± 1.33 g L⁻¹, and GABA production increased from 4.02 ± 0.95 to 18.66 ± 2.11 g L⁻¹ after 84-h cultivation. Under optimal urea supplementation, L-glutamate continued to be consumed, GABA continued to accumulate after 36 h of fermentation, and the pH level fluctuated. GABA production increased to a maximum level of 27.13 ± 0.54 g L⁻¹ after 120-h flask cultivation and 26.32 g L⁻¹ after 60-h fed-batch fermentation. The conversion ratio of L-glutamate to GABA reached 0.60-0.74 mol mol⁻¹. By co-expressing gadB1 and gadB2 and optimising the urea addition method, C. glutamicum was genetically improved for de novo biosynthesis of GABA from its own accumulated L-glutamate.

  10. Neuromuscular partitioning in the extensor carpi radialis longus and brevis based on intramuscular nerve distribution patterns: A three-dimensional modeling study.

    Science.gov (United States)

    Ravichandiran, Mayoorendra; Ravichandiran, Nisanthini; Ravichandiran, Kajeandra; McKee, Nancy H; Richardson, Denyse; Oliver, Michele; Agur, Anne M

    2012-04-01

    Differential activation of specific regions within a skeletal muscle has been linked to the presence of neuromuscular compartments. However, few studies have investigated the extra- or intramuscular innervation throughout the muscle volume of extensor carpi radialis longus (ECRL) and brevis (ECRB). The aim of this study was to determine the presence of neuromuscular partitions in ECRL and ECRB based on the extra- and intramuscular innervation using three-dimensional modeling. The extra- and intramuscular nerve distribution was digitized and reconstructed in 3D in all the muscle volumes using Autodesk Maya in seven formalin embalmed cadaveric specimens (mean age, 75.7 ± 15.2 years). The intramuscular nerve distribution was modeled in all the muscle volumes. ECRL was found to have two neuromuscular compartments, superficial and deep. One branch from the radial nerve proper was found to innervate ECRL. This branch was divided into anterior and posterior branches to the superficial and deep compartments, respectively. Five innervation patterns were identified in ECRB with partitioning of the muscle belly into two, three, or four compartments, in a proximal to distal direction depending on the number of nerve branches entering the muscle belly. The ECRL and ECRB both demonstrated neuromuscular compartmentalization based on intramuscular innervation. According to the partitioning hypothesis, a muscle may be differentially activated depending on the required function of the muscle, thus allowing multifunctional muscles to contribute to a variety of movements. Therefore, the increased number of neuromuscular partitions in ECRB when compared with ECRL could be due to the need for more differential recruitment in the ECRB depending on force requirements. Copyright © 2011 Wiley Periodicals, Inc.

  11. Antimycobacterial natural products from Moroccan medicinal plants: Chemical composition, bacteriostatic and bactericidal profile of Thymus satureioides and Mentha pulegium essential oils

    Directory of Open Access Journals (Sweden)

    Marwa Chraibi

    2016-10-01

    Conclusions: It is clearly evident from the results obtained that the Moroccan medicinal plants have great potential to be used as anti-tuberculosis agents. These findings may help scientists to undertake several research projects to discover useful natural product as new anti-tuberculosis drug.

  12. Surface display of the receptor-binding region of the Lactobacillus brevis S-layer protein in Lactococcus lactis provides nonadhesive lactococci with the ability to adhere to intestinal epithelial cells.

    Science.gov (United States)

    Avall-Jääskeläinen, Silja; Lindholm, Agneta; Palva, Airi

    2003-04-01

    Lactobacillus brevis is a promising lactic acid bacterium for use as a probiotic dietary adjunct and a vaccine vector. The N-terminal region of the S-layer protein (SlpA) of L. brevis ATCC 8287 was recently shown to mediate adhesion to various human cell lines in vitro. In this study, a surface display cassette was constructed on the basis of this SlpA receptor-binding domain, a proteinase spacer, and an autolysin anchor. The cassette was expressed under control of the nisA promoter in Lactococcus lactis NZ9000. Western blot assay of lactococcal cell wall extracts with anti-SlpA antibodies confirmed that the SlpA adhesion domain of the fusion protein was expressed and located within the cell wall layer. Whole-cell enzyme-linked immunosorbent assay and immunofluorescence microscopy verified that the SlpA adhesion-mediating region was accessible on the lactococcal cell surface. In vitro adhesion assays with the human intestinal epithelial cell line Intestine 407 indicated that the recombinant lactococcal cells had gained an ability to adhere to Intestine 407 cells significantly greater than that of wild-type L. lactis NZ9000. Serum inhibition assay further confirmed that adhesion of recombinant lactococci to Intestine 407 cells was indeed mediated by the N terminus-encoding part of the slpA gene. The ability of the receptor-binding region of SlpA to adhere to fibronectin was also confirmed with this lactococcal surface display system. These results show that, with the aid of the receptor-binding region of the L. brevis SlpA protein, the ability to adhere to gut epithelial cells can indeed be transferred to another, nonadhesive, lactic acid bacterium.

  13. Lowering temperature to increase chemical oxidation efficiency: the effect of temperature on permanganate oxidation rates of five types of well defined organic matter, two natural soils, and three pure phase products.

    Science.gov (United States)

    de Weert, J P A; Keijzer, T J S; van Gaans, P F M

    2014-12-01

    In situ chemical oxidation (ISCO) is a soil remediation technique to remove organic pollutants from soil and groundwater with oxidants, like KMnO4. However, also natural organic compounds in soils are being oxidized, which makes the technique less efficient. Laboratory experiments were performed to investigate the influence of temperature on this efficiency, through its effect on the relative oxidation rates - by permanganate - of natural organic compounds and organic pollutants at 16 and 15°C. Specific types of organic matter used were cellulose, oak wood, anthracite, reed - and forest peat, in addition to two natural soils. Dense Non-Aqueous Phase Liquid-tetrachloroethene (DNAPL-PCE), DNAPL trichloroethene (DNAPL-TCE) and a mixture of DNAPL-PCE, -TCE and -hexachlorobutadiene were tested as pollutants. Compared to 16°C, oxidation was slower at 5°C for the specific types of organic matter and the natural soils, with exception of anthracite, which was unreactive. The oxidation rate of DNAPL TCE was lower at 5°C too. However, at this temperature oxidation was fast, implying that no competitive loss to natural organic compounds will be expected in field applications by lowering temperature. Oxidation of DNAPL-PCE and PCE in the mixture proceeded at equal rates at both temperatures, due to the dissolution rate as limiting factor. These results show that applying permanganate ISCO to DNAPL contamination at lower temperatures will limit the oxidation of natural organic matter, without substantially affecting the oxidation rate of the contaminant. This will make such remediation more effective and sustainable in view of protecting natural soil quality. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. “Per fortuna ci sono le mucche.” Brevi considerazioni sul valore del pañcgavya.

    Directory of Open Access Journals (Sweden)

    Deborah Nadal

    2014-12-01

    Full Text Available This article analyses the value of pañcgavya and its role in Hindu culture and religion. “Pañcgavya” is a Sanskrit word which means “the five of the cow”, i.e. milk, curd, clarified butter, dung and urine. These five products can be used one by one or combined together in proper ratio. For centuries they have been used in traditional Hindu rituals as prasad (religious offering consumed by the worshippers, as medicaments in Ayurvedic medicine and as fertilizers and pesticides. Nowadays these cow products are utilized for personal hygiene and for household cleanliness as well. The medicinal usage of pañcgavya, particularly cow urine, is commonly known as “cowpathy” and is very appreciated by Indian, especially Hindu, consumers. The reasons of this success are the eco-friendliness of these natural products and, above all, the fact that they come from the body of the most esteemed animal of India. In Hindu culture the cow is considered to be the highest example of purity and perfection and the best emblem of generosity and plenty. The “five of the cow” are the most important products of this magnanimity.

  15. Cultivated strains of Agaricus bisporus and A. brasiliensis: chemical characterization and evaluation of antioxidant and antimicrobial properties for the final healthy product--natural preservatives in yoghurt.

    Science.gov (United States)

    Stojković, Dejan; Reis, Filipa S; Glamočlija, Jasmina; Ćirić, Ana; Barros, Lillian; Van Griensven, Leo J L D; Ferreira, Isabel C F R; Soković, Marina

    2014-07-25

    Agaricus bisporus (J. E. Lange) Emil J. Imbach and Agaricus brasiliensis Wasser, M. Didukh, Amazonas & Stamets are edible mushrooms. We chemically characterized these mushrooms for nutritional value, hydrophilic and lipophilic compounds. The antioxidant and antimicrobial activities of methanolic and ethanolic extracts were assessed. Hepatotoxicity was also evaluated. The ethanolic extract of both species was tested for inhibition of Listeria monocytogenes growth in yoghurt. Both species proved to be a good source of bioactive compounds. A. brasiliensis was richer in polyunsaturated fatty acids and revealed the highest concentration of phenolic acids, and tocopherols. A. bisporus showed the highest monounsaturated fatty acids and ergosterol contents. A. brasiliensis revealed the highest antioxidant potential, and its ethanolic extract displayed the highest antibacterial potential; the methanolic extract of A. bisporus revealed the highest antifungal activity. A. brasiliensis possessed better preserving properties in yoghurt.

  16. Stereochemistry of Complex Marine Natural Products by Quantum Mechanical Calculations of NMR Chemical Shifts: Solvent and Conformational Effects on Okadaic Acid

    Directory of Open Access Journals (Sweden)

    Humberto J. Domínguez

    2014-01-01

    Full Text Available Marine organisms are an increasingly important source of novel metabolites, some of which have already inspired or become new drugs. In addition, many of these molecules show a high degree of novelty from a structural and/or pharmacological point of view. Structure determination is generally achieved by the use of a variety of spectroscopic methods, among which NMR (nuclear magnetic resonance plays a major role and determination of the stereochemical relationships within every new molecule is generally the most challenging part in structural determination. In this communication, we have chosen okadaic acid as a model compound to perform a computational chemistry study to predict 1H and 13C NMR chemical shifts. The effect of two different solvents and conformation on the ability of DFT (density functional theory calculations to predict the correct stereoisomer has been studied.

  17. Type I allergy to natural rubber latex and type IV allergy to rubber chemicals in health care workers with glove-related skin symptoms.

    Science.gov (United States)

    Nettis, E; Assennato, G; Ferrannini, A; Tursi, A

    2002-03-01

    It has been established that there are type I and type IV allergens in latex gloves. The purpose of the study was to establish the prevalence of rubber glove-induced skin symptoms among health care workers in one Italian hospital. Health care workers (n = 1584) were evaluated using a written questionnaire and 295 respondents with glove-induced skin symptoms were tested. We performed: skin prick test with latex glove extract and commercial latex, and environmental and food allergens; glove use test; patch tests with a rubber additive series; and RASTs. Hospital employees who used or had used latex gloves at work were 1294. Three hundred and sixteen (24.4%) reported glove-induced symptoms, namely, cutaneous symptoms in all the cases and non-cutaneous symptoms in 105 subjects (8.1%). Twenty-seven of the 295 symptomatic employees tested (9.1%) were latex sensitive. Thirty-one patients (10.5%) exhibited positive patch test to rubber-related allergens. The most positive readings were obtained from the Thiuram mix and the Carba mix, with 12 and 9 positivities, respectively. The risk factors for latex skin sensitization were: a previous history of atopy and asthma; history of surgery; pre-existing hand dermatitis; work-related symptoms; and positive skin tests to common inhalant and certain foods (P skin complaints of latex gloves are related to skin irritation rather than to allergy. The immediate allergy to latex and the delayed allergy to rubber chemicals suggest that all the health care workers with glove-related dermatitis should undergo both skin prick test and glove use test to detect type I hypersensitivity to latex, and patch test to detect type IV hypersensitivity to rubber chemicals.

  18. Variation of Chemical Composition in Flowers and Leaves Essential Oils Among Natural Population of Tunisian Glebionis coronaria (L.) Tzvelev (Asteraceae).

    Science.gov (United States)

    Haouas, Dalila; Cioni, Pier Luigi; Flamini, Guido; Ben Halima-Kamel, Monia; Ben Hamouda, Mohamed Habib

    2016-10-01

    The aim of this study was to assess the percentage and constituents variations in flowers and leaves essential oil of three Glebionis coronaria (L.) Tzvelev population, growing wildly in three different ecotypes (Utique, M'saken, and Sahara Lektar) in Tunisia. The chemical compositions of these essential oils were analyzed by the GC and GC/MS systems. Qualitative and quantitative differences were recorded between essential oils extracted from plants collected from the three geographical provinces and between organs of the same plant (leaves and flowers). In fact, 161 components representing 87.2 - 96.5% of the whole oils were identified. Myrcene (3.2 - 35.7%), (Z)-β-ocimene (0.6 - 23.0%), camphor (0.6 - 17.2%), cis-chrysanthenol (0 - 6.9%), cis-chrysanthenyl acetate (1.1 - 17.9%), isobornyl acetate (1.6 - 3.5%), (E)-β-farnesene (0 - 6.0%), germacrene D (0 - 8.7%), and (E,E)-α-farnesene (0.7 - 12.4%) were the predominant components in the oils. These major constituents occur in different amounts depending on the organs (leaves or flowers) and the geographical origin of the plant. The chemotaxonomic usefulness of these data was discussed according to results of principal component analysis (PCA). The scores, together with the loadings, revealed a different chemical pattern for each population. © 2016 Wiley-VHCA AG, Zürich.

  19. Chemical Emergencies

    Science.gov (United States)

    When a hazardous chemical has been released, it may harm people's health. Chemical releases can be unintentional, as in the case of an ... the case of a terrorist attack with a chemical weapon. Some hazardous chemicals have been developed by ...

  20. Deciphering the "chemical" nature of the exotic isotopes of hydrogen by the MC-QTAIM analysis: the positively charged muon and the muonic helium as new members of the periodic table.

    Science.gov (United States)

    Goli, Mohammad; Shahbazian, Shant

    2014-04-14

    This report is a primarily survey on the chemical nature of some exotic species containing the positively charged muon and the muonic helium, i.e., the negatively charged muon plus helium nucleus, as exotic isotopes of hydrogen, using the newly developed multi-component quantum theory of atoms in molecules (MC-QTAIM) analysis, employing ab initio non-Born-Oppenhiemer wavefunctions. Accordingly, the "atoms in molecules" analysis performed on various asymmetric exotic isotopomers of the hydrogen molecule, recently detected experimentally [Science, 2011, 331, 448], demonstrates that both the exotic isotopes are capable of forming atoms in molecules and retaining the identity of hydrogen atoms. Various derived properties of atomic basins containing the muonic helium cast no doubt that apart from its short life time, it is a heavier isotope of hydrogen while the properties of basins containing the positively charged muon are more remote from those of the orthodox hydrogen basins, capable of appreciable donation of electrons as well as large charge polarization. However, with some tolerance, they may also be categorized as hydrogen basins though with a smaller electronegativity. All in all, the present study also clearly demonstrates that the MC-QTAIM analysis is an efficient approach to decipher the chemical nature of species containing exotic constituents, which are difficult to elucidate by experimental and/or alternative theoretical schemes.

  1. Flavoring Production in Kamut®, Quinoa and Wheat Doughs Fermented by Lactobacillus paracasei, Lactobacillus plantarum, and Lactobacillus brevis: A SPME-GC/MS Study.

    Science.gov (United States)

    Di Renzo, Tiziana; Reale, Anna; Boscaino, Floriana; Messia, Maria C

    2018-01-01

    This study identified the odor-active compounds and the qualitative characteristics of doughs from "ancient" grains flours fermented by lactic acid bacteria. For this purpose doughs made with quinoa and Kamut® flours have been produced and inoculated with strains belonging to the species Lactobacillus paracasei, Lactobacillus plantarum and Lactobacillus brevis and compared with fermented doughs made from 100% wheat flour. The quality of the doughs was determined by assessment of pH, total titratable acidity, lactic acid bacteria growth and flavor compounds. The results showed that lactic acid bacteria used were able to grow in the different substrates reaching more than 9.0 log CFU/g after 24 h fermentation, although the best microbial growth was recorded in the doughs made with quinoa flour fermented with Lactobacillus paracasei I1. Good acidification and heterogeneous aromatic profile were recognized in all the doughs even if the volatile composition mainly derived from microbial specie. Among all the used strains, mostly Lactobacillus paracasei I1 positively contributed to the aromatic profile of the doughs, independently from flour type, producing the highest amount of different ketones such as, diacetyl, acetoin, 2,6-dimethyl-4-heptanone, 5-methyl-3-hexanone, 4-methyl-3-penten-2-one, volatile compounds highly appreciated in the bakery products for their buttery, fatty and fruity notes. So, the positive characteristic of Lactobacillus paracasei I1 to enhance the production of desired volatile compounds could make it suitable as adjunct culture starter in the bakery industry. Many differences in volatile organic compounds derived also by the type of flour used. Quinoa fermented doughs were characterized for specific nutty, roasted, acid and buttery tones derived from pyrazines, ketones and acid compounds whereas Kamut® fermented doughs were characterized for fruity, rose, green and sweet tones derived from aldehydes and ketones production. So, the use of

  2. Flavoring Production in Kamut®, Quinoa and Wheat Doughs Fermented by Lactobacillus paracasei, Lactobacillus plantarum, and Lactobacillus brevis: A SPME-GC/MS Study

    Directory of Open Access Journals (Sweden)

    Tiziana Di Renzo

    2018-03-01

    Full Text Available This study identified the odor-active compounds and the qualitative characteristics of doughs from “ancient” grains flours fermented by lactic acid bacteria. For this purpose doughs made with quinoa and Kamut® flours have been produced and inoculated with strains belonging to the species Lactobacillus paracasei, Lactobacillus plantarum and Lactobacillus brevis and compared with fermented doughs made from 100% wheat flour. The quality of the doughs was determined by assessment of pH, total titratable acidity, lactic acid bacteria growth and flavor compounds. The results showed that lactic acid bacteria used were able to grow in the different substrates reaching more than 9.0 log CFU/g after 24 h fermentation, although the best microbial growth was recorded in the doughs made with quinoa flour fermented with Lactobacillus paracasei I1. Good acidification and heterogeneous aromatic profile were recognized in all the doughs even if the volatile composition mainly derived from microbial specie. Among all the used strains, mostly Lactobacillus paracasei I1 positively contributed to the aromatic profile of the doughs, independently from flour type, producing the highest amount of different ketones such as, diacetyl, acetoin, 2,6-dimethyl-4-heptanone, 5-methyl-3-hexanone, 4-methyl-3-penten-2-one, volatile compounds highly appreciated in the bakery products for their buttery, fatty and fruity notes. So, the positive characteristic of Lactobacillus paracasei I1 to enhance the production of desired volatile compounds could make it suitable as adjunct culture starter in the bakery industry. Many differences in volatile organic compounds derived also by the type of flour used. Quinoa fermented doughs were characterized for specific nutty, roasted, acid and buttery tones derived from pyrazines, ketones and acid compounds whereas Kamut® fermented doughs were characterized for fruity, rose, green and sweet tones derived from aldehydes and ketones

  3. Flavoring Production in Kamut®, Quinoa and Wheat Doughs Fermented by Lactobacillus paracasei, Lactobacillus plantarum, and Lactobacillus brevis: A SPME-GC/MS Study

    Science.gov (United States)

    Di Renzo, Tiziana; Reale, Anna; Boscaino, Floriana; Messia, Maria C.

    2018-01-01

    This study identified the odor-active compounds and the qualitative characteristics of doughs from “ancient” grains flours fermented by lactic acid bacteria. For this purpose doughs made with quinoa and Kamut® flours have been produced and inoculated with strains belonging to the species Lactobacillus paracasei, Lactobacillus plantarum and Lactobacillus brevis and compared with fermented doughs made from 100% wheat flour. The quality of the doughs was determined by assessment of pH, total titratable acidity, lactic acid bacteria growth and flavor compounds. The results showed that lactic acid bacteria used were able to grow in the different substrates reaching more than 9.0 log CFU/g after 24 h fermentation, although the best microbial growth was recorded in the doughs made with quinoa flour fermented with Lactobacillus paracasei I1. Good acidification and heterogeneous aromatic profile were recognized in all the doughs even if the volatile composition mainly derived from microbial specie. Among all the used strains, mostly Lactobacillus paracasei I1 positively contributed to the aromatic profile of the doughs, independently from flour type, producing the highest amount of different ketones such as, diacetyl, acetoin, 2,6-dimethyl-4-heptanone, 5-methyl-3-hexanone, 4-methyl-3-penten-2-one, volatile compounds highly appreciated in the bakery products for their buttery, fatty and fruity notes. So, the positive characteristic of Lactobacillus paracasei I1 to enhance the production of desired volatile compounds could make it suitable as adjunct culture starter in the bakery industry. Many differences in volatile organic compounds derived also by the type of flour used. Quinoa fermented doughs were characterized for specific nutty, roasted, acid and buttery tones derived from pyrazines, ketones and acid compounds whereas Kamut® fermented doughs were characterized for fruity, rose, green and sweet tones derived from aldehydes and ketones production. So, the use of

  4. Interactive effect of Brevibacillus brevis and Glomus mosseae, both isolated from Cd contaminated soil, on plant growth, physiological mycorrhizal fungal characteristics and soil enzymatic activities in Cd polluted soil

    International Nuclear Information System (INIS)

    Vivas, A.; Barea, J.M.; Azcon, R.

    2005-01-01

    The interaction between two autochthonous microorganisms (Brevibacillus brevis and Glomus mosseae) isolated from Cd amended soil increased plant growth, arbuscular mycorrhizal (AM) colonization and physiological characteristics of the AM infection (measured as SDH or ALP activities). The enhanced plant Cd tolerance after coinoculation with native microorganisms seemed to be a consequence of increased P and K acquisition and, simultaneously, of decreased concentration of Cd, Cr, Mn, Cu, Mo, Fe and Ni in plant tissue. Autochthonous microbial strains were more efficient for nutrient uptake, to immobilize metals and decrease their translocation to the shoot than reference G. mosseae (with or without bacteria). Indole acetic acid produced by B. brevis may be related to its ability for improving root growth, nodule production and AM fungal intra and extraradical development. Dehydrogenase, phosphatase and β-glucosidase activities, indicative of microbial metabolism and soil fertility, were maximized by the coinoculation of autochthonous microorganisms in cadmium polluted conditions. As a consequence, the use of native microorganisms may result very efficient in bioremediation. - Endemic isolates of bacteria and fungi were effective in bioremediation

  5. Accumulation of Dechlorane Plus flame retardant in terrestrial passerines from a nature reserve in South China: The influences of biological and chemical variables

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Ying [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); University of the Chinese Academy of Sciences, Beijing 100049 (China); Wu, Jiang-Ping, E-mail: jpwu@gig.ac.cn [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Tao, Lin [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); University of the Chinese Academy of Sciences, Beijing 100049 (China); Mo, Ling [Hainan Research Academy of Environmental Sciences, Haikou 571126 (China); Zheng, Xiao-Bo; Tang, Bin [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); University of the Chinese Academy of Sciences, Beijing 100049 (China); Luo, Xiao-Jun; Mai, Bi-Xian [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)

    2015-05-01

    Although a number of studies have addressed the bioaccumulation of Dechlorane Plus (DP) flame retardant in wildlife, few data are available on terrestrial organisms. This study examined the presence of DP isomers in the muscle tissue of seven terrestrial resident passerine species, i.e., the great tit (Parus major), the oriental magpie-robin (Copsychus saularis), the red-whiskered bulbul (Pycnonotus jocosus), the light-vented bulbul (Pycnonotus sinensis), the streak-breasted scimitar babbler (Pomatorhinus ruficollis), the long-tailed shrike (Lanius schach), and the orange-headed thrush (Zoothera citrina), from a national nature reserve located in South China. The ∑DP (sum of syn-DP and anti-DP) concentrations ranged from 1.2 to 104 ng/g lipid weight, with significantly higher levels in insectivorous birds than in omnivorous birds. The overall exposure to DP isomers of the current passerines may be attributed to the intensive release of this pollutant from electronic waste recycling sites and industrial zones in the vicinity of the nature reserve. Species-specific DP isomeric profiles were also found, with significantly greater f{sub anti} values (the isomer fractions of anti-DP) in the red-whiskered bulbul and the oriental magpie-robin. Additionally, the f{sub anti} values were significantly negatively correlated to ∑DP concentrations for the individual bird samples, suggesting the influence of DP concentrations on the isomeric profiles. - Highlights: • We investigated the occurrence of DP in seven species of terrestrial passerines. • Insectivorous birds accumulated higher ∑DP concentrations than omnivorous birds. • Inter-species differences in the f{sub anti} values were observed. • The f{sub anti} values were significantly correlated to DP concentrations.

  6. Accumulation of Dechlorane Plus flame retardant in terrestrial passerines from a nature reserve in South China: The influences of biological and chemical variables

    International Nuclear Information System (INIS)

    Peng, Ying; Wu, Jiang-Ping; Tao, Lin; Mo, Ling; Zheng, Xiao-Bo; Tang, Bin; Luo, Xiao-Jun; Mai, Bi-Xian

    2015-01-01

    Although a number of studies have addressed the bioaccumulation of Dechlorane Plus (DP) flame retardant in wildlife, few data are available on terrestrial organisms. This study examined the presence of DP isomers in the muscle tissue of seven terrestrial resident passerine species, i.e., the great tit (Parus major), the oriental magpie-robin (Copsychus saularis), the red-whiskered bulbul (Pycnonotus jocosus), the light-vented bulbul (Pycnonotus sinensis), the streak-breasted scimitar babbler (Pomatorhinus ruficollis), the long-tailed shrike (Lanius schach), and the orange-headed thrush (Zoothera citrina), from a national nature reserve located in South China. The ∑DP (sum of syn-DP and anti-DP) concentrations ranged from 1.2 to 104 ng/g lipid weight, with significantly higher levels in insectivorous birds than in omnivorous birds. The overall exposure to DP isomers of the current passerines may be attributed to the intensive release of this pollutant from electronic waste recycling sites and industrial zones in the vicinity of the nature reserve. Species-specific DP isomeric profiles were also found, with significantly greater f anti values (the isomer fractions of anti-DP) in the red-whiskered bulbul and the oriental magpie-robin. Additionally, the f anti values were significantly negatively correlated to ∑DP concentrations for the individual bird samples, suggesting the influence of DP concentrations on the isomeric profiles. - Highlights: • We investigated the occurrence of DP in seven species of terrestrial passerines. • Insectivorous birds accumulated higher ∑DP concentrations than omnivorous birds. • Inter-species differences in the f anti values were observed. • The f anti values were significantly correlated to DP concentrations

  7. A theory for the origin of a self-replicating chemical system. I - Natural selection of the autogen from short, random oligomers

    Science.gov (United States)

    White, D. H.

    1980-01-01

    A general theory is presented for the origin of a self-replicating chemical system, termed an autogen, which is capable of both crude replication and translation (protein synthesis). The theory requires the availability of free energy and monomers to the system, a significant background low-yield synthesis of kinetically stable oligopeptides and oligonucleotides, the localization of the oligomers, crude oligonucleotide selectivity of amino acids during oligopeptide synthesis, crude oligonucleotide replication, and two short peptide families which catalyze replication and translation, to produce a localized group of at least one copy each of two protogenes and two protoenzymes. The model posits a process of random oligomerization, followed by the random nucleation of functional components and the rapid autocatalytic growth of the functioning autogen to macroscopic amounts, to account for the origin of the first self-replicating system. Such a process contains steps of such high probability and short time periods that it is suggested that the emergence of an autogen in a laboratory experiment of reasonable time scale may be possible.

  8. A comprehensive study of the toxicity of natural multi-contaminated sediments: New insights brought by the use of a combined approach using the medaka embryo-larval assay and physico-chemical analyses.

    Science.gov (United States)

    Barjhoux, Iris; Clérandeau, Christelle; Menach, Karyn Le; Anschutz, Pierre; Gonzalez, Patrice; Budzinski, Hélène; Morin, Bénédicte; Baudrimont, Magalie; Cachot, Jérôme

    2017-08-01

    Sediment compartment is a long term sink for pollutants and a secondary source of contamination for aquatic species. The abiotic factors controlling the bioavailability and thus the toxicity of complex mixtures of pollutants accumulated in sediments are poorly documented. To highlight the different factors influencing sediment toxicity, we identified and analyzed the physico-chemical properties, micro-pollutant contents, and toxicity level of six contrasted sediments in the Lot-Garonne continuum. Sediment toxicity was evaluated using the recently described Japanese medaka (Oryzias latipes) embryo-larval assay with direct exposure to whole sediment (MELAc). Multiple toxicity endpoints including embryotoxicity, developmental defects and DNA damage were analyzed in exposed embryos. Chemical analyses revealed significant variations in the nature and contamination profile of sediments, mainly impacted by metallic trace elements and, unexpectedly, polycyclic aromatic hydrocarbons. Exposure to sediments induced different toxic impacts on medaka early life stages when compared with the reference site. Principal component analysis showed that the toxic responses following exposure to sediments from the Lot River and its tributary were associated with micro-pollutant contamination: biometric measurements, hatching success, genotoxicity, craniofacial deformities and yolk sac malabsorption were specifically correlated to metallic and organic contaminants. Conversely, the main biological responses following exposure to the Garonne River sediments were more likely related to their physico-chemical properties than to their contamination level. Time to hatch, cardiovascular injuries and spinal deformities were correlated to organic matter content, fine particles and dissolved oxygen levels. These results emphasize the necessity of combining physico-chemical analysis of sediment with toxicity assessment to accurately evaluate the environmental risks associated with sediment

  9. 'Pharmaceutical and chemical personal care products determination in natural and residual waters; Determinaciond e farmacos y productos quimicos de cuidado personal (PPcps) en aguas naturales y residuales

    Energy Technology Data Exchange (ETDEWEB)

    Jordi, R.; Gomez, M.; Vazquez, M. J.

    2004-07-01

    A quantitative, selected and sensitive method on liquid-liquid extraction (LLE)coupled to analysis by gas chromatography/mass spectrometry (GC/MS) is described for analysis of a selected group of chemicals compounds used as pharmaceuticals and personal care products (PPcPs). They are considered as persistent-emergent pollutants in natural and residual waters. The studied PPCPs- ibuprofen, diclofenac, benzafibrate, diazepan, carbamazepine, galaxolide, tonalide, celestolide, traseolide and cashmeran-are representative for three categories of PPCPs: acids and neutrals pahrmaceuticals and polycyclic synthetic musk, all of them with wide use. The effectiveness of the proposed method was higher than 90% in three different matrix, quantification limits, were at order of ng/L range. The estimated uncertainty was about 23% for all compounds. to asses the performance of the method, natural and wastewaters were analyzed. the obtained results showed that galaxolide, tonalide, ibuprofen, benzafibrate are the most frequently PPCP identified in these waters. Currently, concentrations found in the wastewater are ten times higher than those found in natural waters. No PPCP or very low concentrations were found in the tap water samples analyzed. (Author) 13 refs.

  10. Chemical Analysis of Reaction Rims on Olivine Crystals in Natural Samples of Black Dacite Using Energy-Dispersive X-Ray Spectroscopy, Lassen Peak, CA.

    Science.gov (United States)

    Graham, N. A.

    2014-12-01

    Lassen Volcanic Center is the southernmost volcanic region in the Cascade volcanic arc formed by the Cascadia Subduction Zone. Lassen Peak last erupted in 1915 in an arc related event producing a black dacite material containing xenocrystic olivine grains with apparent orthopyroxene reaction rims. The reaction rims on these olivine grains are believed to have formed by reactions that ensued from a mixing/mingling event that occurred prior to eruption between the admixed mafic andesitic magma and a silicic dacite host material. Natural samples of the 1915 black dacite from Lassen Peak, CA were prepared into 15 polished thin sections and carbon coated for analysis using a FEI Quanta 250 Scanning Electron Microscope (SEM) to identify and measure mineral textures and disequilibrium reaction rims. Observed mineralogical textures related to magma mixing include biotite and amphibole grains with apparent dehydration/breakdown rims, pyroxene-rimmed quartz grains, high concentration of microlites in glass matrix, and pyroxene/amphibole reaction rims on olivine grains. Olivine dissolution is evidenced as increased iron concentration toward convolute edges of olivine grains as observed by Backscatter Electron (BSE) imagery and elemental mapping using NSS spectral imaging software. In an attempt to quantify the area of reaction rim growth on olivine grains within these samples, high-resolution BSE images of 30 different olivine grains were collected along with Energy-Dispersive X-Ray Spectroscopy (EDS) of different phases. Olivine cores and rims were extracted from BSE images using Photoshop and saved as separate image files. ImageJ software was used to calculate the area (μm2) of the core and rim of these grains. Average pyroxene reaction rim width for 30 grains was determined to be 11.68+/-1.65 μm. Rim widths of all 30 grains were averaged together to produce an overall average rim width for the Lassen Peak black dacite. By quantifying the reaction rims on olivine grains

  11. Effect of different drying techniques on flowability characteristics and chemical properties of natural carbohydrate-protein Gum from durian fruit seed

    Directory of Open Access Journals (Sweden)

    Mirhosseini Hamed

    2013-01-01

    Full Text Available Abstract Background A natural carbohydrate biopolymer was extracted from the agricultural biomass waste (durian seed. Subsequently, the crude biopolymer was purified by using the saturated barium hydroxide to minimize the impurities. Finally, the effect of different drying techniques on the flow characteristics and functional properties of the purified biopolymer was investigated. The present study elucidated the main functional characteristics such as flow characteristics, water- and oil-holding capacity, solubility, and foaming capacity. Results In most cases except for oven drying, the bulk density decreased, thus increasing the porosity. This might be attributed to the increase in the inter-particle voids of smaller sized particles with larger contact surface areas per unit volume. The current study revealed that oven-dried gum and freeze-dried gum had the highest and lowest compressibility index, thus indicating the weakest and strongest flowability among all samples. In the present work, the freeze-dried gum showed the lowest angle of repose, bulk, tapped and true density. This indicates the highest porosity degree of freeze dried gum among dried seed gums. It also exhibited the highest solubility, and foaming capacity thus providing the most desirable functional properties and flow characteristics among all drying techniques. Conclusion The present study revealed that freeze drying among all drying techniques provided the most desirable functional properties and flow characteristics for durian seed gum.

  12. The influence of oscillating electromagnetic fields on membrane structure and function: Synthetic liposome and natural membrane bilayer systems with direct application to the controlled delivery of chemical agents

    International Nuclear Information System (INIS)

    Liburdy, R.P.; de Manincor, D.; Fingado, B.

    1989-09-01

    Investigations have been conducted to determine if an imposed electromagnetic field can influence membrane transport, and ion and drug permeability in both synthetic and natural cell membrane systems. Microwave fields enhance accumulation of sodium in the lymphocyte and induce protein shedding at Tc. Microwaves also trigger membrane permeability of liposome systems under specific field exposure conditions. Sensitivity varies in a defined way in bilayers displaying a membrane structural phase transition temperature, Tc; maximal release was observed at or near Tc. Significantly, liposome systems without a membrane phase transition were also found to experience permeability increases but, in contrast, this response was temperature independent. The above results indicate that field-enhanced drug release occurs in liposome vesicles that possess a Tc as well as non-Tc liposomes. Additional studies extend non-Tc liposome responses to the in vivo case in which microwaves trigger Gentamicin release from a liposome ''depot'' placed subcutaneously in the rat hind leg. In addition, evidence is provided that cell surface sequestered liposomes can be triggered by microwave fields to release drugs directly into target cells. 24 refs., 6 figs

  13. [Determination of the Plant Origin of Licorice Oil Extract, a Natural Food Additive, by Principal Component Analysis Based on Chemical Components].

    Science.gov (United States)

    Tada, Atsuko; Ishizuki, Kyoko; Sugimoto, Naoki; Yoshimatsu, Kayo; Kawahara, Nobuo; Suematsu, Takako; Arifuku, Kazunori; Fukai, Toshio; Tamura, Yukiyoshi; Ohtsuki, Takashi; Tahara, Maiko; Yamazaki, Takeshi; Akiyama, Hiroshi

    2015-01-01

    "Licorice oil extract" (LOE) (antioxidant agent) is described in the notice of Japanese food additive regulations as a material obtained from the roots and/or rhizomes of Glycyrrhiza uralensis, G. inflata or G. glabra. In this study, we aimed to identify the original Glycyrrhiza species of eight food additive products using LC/MS. Glabridin, a characteristic compound in G. glabra, was specifically detected in seven products, and licochalcone A, a characteristic compound in G. inflata, was detected in one product. In addition, Principal Component Analysis (PCA) (a kind of multivariate analysis) using the data of LC/MS or (1)H-NMR analysis was performed. The data of thirty-one samples, including LOE products used as food additives, ethanol extracts of various Glycyrrhiza species and commercially available Glycyrrhiza species-derived products were assessed. Based on the PCA results, the majority of LOE products was confirmed to be derived from G. glabra. This study suggests that PCA using (1)H-NMR analysis data is a simple and useful method to identify the plant species of origin of natural food additive products.

  14. Taking advantage of natural gas for the energy and fuel supply for the Brazilian energy intensive industries: aluminium, siderurgy and chemical products; O aproveitamento do gas natural para o suprimento de energia e combustivel para as industrias energointensivas brasileiras: aluminio, siderurgia e produtos quimicos

    Energy Technology Data Exchange (ETDEWEB)

    Romero, Jose Fernando Leme [Universidade Sao Paulo (USP), SP (Brazil). Programa Interunidades de Pos Graduacao em Energia]. E-mail: romero@iee.usp.br

    2006-07-01

    This work intend to analyse natural gas success in the energy generation for siderurgy industry, aluminium and basic organic chemical products. There is a necessity to inform economy-policy and the energy policy relationship, showing the Brazilian State actuation in the economic development mechanism and electric energy supply. Cast iron and iron, metals and no-irons are considered as electric intensives and energy intensives industry activities. These are sectors that produce merchandises for exportation and spend many quantities of electrical energy for each produced physical unity of law aggregate economic value. (author)

  15. Repeated applications of compost and manure mainly affect the size and chemical nature of particulate organic matter in a loamy soil after 8 years

    Science.gov (United States)

    Peltre, Clement; Dignac, Marie-France; Doublet, Jeremy; Plante, Alain; Houot, Sabine

    2013-04-01

    Land application of exogenous organic matter (EOM) of residual origin can help to maintain or increase soil organic carbon (SOC) stocks. However, it remains necessary to quantify and predict the soil C accumulation and to determine under which form the C accumulates. Changes to the chemical composition of soil organic matter (SOM) after repeated applications of composts and farmyard manure were investigated in a field experiment (Qualiagro experiment, Ile-de-France) after 8 years of applications of green waste and sludge compost (GWS), municipal solid waste compost (MSW), biowaste compost (BIOW) or farmyard manure (FYM). The soil was fractionated into particulate organic matter >50 µm (POM), a heavy fraction >50 µm and a 0-50 µm fraction demineralized with hydrofluoric acid (HF). Repeated EOM applications significantly increased total SOC stocks, the C amount in the POM fraction and to a less extent in the 0-50 µm fraction compared to the reference treatment. Compost applications accumulated C preferentially under the form of coarse organic matter of size >50 µm, whereas the FYM accumulated similar C proportions of size >50 µm and 0-50 µm, which was attributed to the presence in the FYM of a fraction of labile C stimulating microbial activity and producing humified by-products together with a fraction of stabilized C directly alimenting the humified fraction of SOC. Pyrolysis-GC/MS and DRIFT spectroscopy revealed enrichment in lignin in the POM fractions of amended soils with GWS, BIOW and FYM. In the soil receiving MSW compost, the pyrolysate of the POM fraction revealed the presence of plastics originating from the MSW compost. A lower C mineralization during laboratory incubation was found for the POM fractions of amended soils compared with the POM from reference soil. This feature was related to a lower ratio of (furfural+acetic acid) / pyrole pyrolysis products in POM of amended vs. reference plots, indicating a higher degree of recalcitrance.. The POM

  16. The Nature of the Chemical Process. 1. Symmetry Evolution – Revised Information Theory, Similarity Principle and Ugly Symmetry

    Directory of Open Access Journals (Sweden)

    Shu-Kun Lin

    2001-03-01

    Full Text Available Abstract: Symmetry is a measure of indistinguishability. Similarity is a continuous measure of imperfect symmetry. Lewis' remark that “gain of entropy means loss of information” defines the relationship of entropy and information. Three laws of information theory have been proposed. Labeling by introducing nonsymmetry and formatting by introducing symmetry are defined. The function L ( L=lnw, w is the number of microstates, or the sum of entropy and information, L=S+I of the universe is a constant (the first law of information theory. The entropy S of the universe tends toward a maximum (the second law law of information theory. For a perfect symmetric static structure, the information is zero and the static entropy is the maximum (the third law law of information theory. Based on the Gibbs inequality and the second law of the revised information theory we have proved the similarity principle (a continuous higher similarity−higher entropy relation after the rejection of the Gibbs paradox and proved the Curie-Rosen symmetry principle (a higher symmetry−higher stability relation as a special case of the similarity principle. The principles of information minimization and potential energy minimization are compared. Entropy is the degree of symmetry and information is the degree of nonsymmetry. There are two kinds of symmetries: dynamic and static symmetries. Any kind of symmetry will define an entropy and, corresponding to the dynamic and static symmetries, there are static entropy and dynamic entropy. Entropy in thermodynamics is a special kind of dynamic entropy. Any spontaneous process will evolve towards the highest possible symmetry, either dynamic or static or both. Therefore the revised information theory can be applied to characterizing all kinds of structural stability and process spontaneity. Some examples in chemical physics have been given. Spontaneous processes of all kinds of molecular

  17. Natural Colorants: Food Colorants from Natural Sources.

    Science.gov (United States)

    Sigurdson, Gregory T; Tang, Peipei; Giusti, M Mónica

    2017-02-28

    The color of food is often associated with the flavor, safety, and nutritional value of the product. Synthetic food colorants have been used because of their high stability and low cost. However, consumer perception and demand have driven the replacement of synthetic colorants with naturally derived alternatives. Natural pigment applications can be limited by lower stability, weaker tinctorial strength, interactions with food ingredients, and inability to match desired hues. Therefore, no single naturally derived colorant can serve as a universal alternative for a specified synthetic colorant in all applications. This review summarizes major environmental and biological sources for natural colorants as well as nature-identical counterparts. Chemical characteristics of prevalent pigments, including anthocyanins, carotenoids, betalains, and chlorophylls, are described. The possible applications and hues (warm, cool, and achromatic) of currently used natural pigments, such as anthocyanins as red and blue colorants, and possible future alternatives, such as purple violacein and red pyranoanthocyanins, are also discussed.

  18. Hyphenation of ultra high performance supercritical fluid chromatography with atmospheric pressure chemical ionisation high resolution mass spectrometry: Part 1. Study of the coupling parameters for the analysis of natural non-polar compounds.

    Science.gov (United States)

    Duval, Johanna; Colas, Cyril; Pecher, Virginie; Poujol, Marion; Tranchant, Jean-François; Lesellier, Eric

    2017-08-04

    An analytical method based on Ultra-High-Performance Supercritical Fluid Chromatography (UHPSFC) coupled with Atmospheric Pressure Chemical Ionization - High-resolution mass spectrometry (APCI-Q-TOF-HRMS) was developed for compounds screening from oily samples. The hyphenation was made using a commercial UHPLC device coupled to a CO 2 pump in order to perform the chromatographic analysis. An adaptation of the injection system for compressible fluids was accomplished for this coupling: this modification of the injection sequence was achieved to prevent unusual variations of the injected volume related to the use of a compressible fluid. UHPSFC-HRMS hyphenation was optimized to enhance the response of the varied compounds from a seed extract (anthraquinones, free fatty acids, diacylglycerols, hydroxylated triacylglycerols and triacylglycerols). No split was used prior to the APCI ionization source, allowing introducing all the compounds in the spectrometer, ensuring a better sensitivity for minor compounds. The effects of a mechanical make-up (T-piece) added before this ionization source was discussed in terms of standard deviation of response, response intensity and fragmentation percentage. The location of the T-piece with regards to the backpressure regulator (BPR), the flow rate and the nature of the make-up solvent were studied. Results show that the effects of the studied parameters depend on the nature of the compounds, whereas the make-up addition favours the robustness of the mass response (quantitative aspect). Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Non disturbing characterization and quantification of natural organic matter (NOM) contained in clay rock pore water by mass spectrometry using electro-spray and atmospheric pressure chemical ionization modes

    International Nuclear Information System (INIS)

    Huclier-Markai, S.; Landesman, C.; Grambow, B.; Rogniaux, H.; Monteau, F.; Vinsot, A.

    2010-01-01

    Document available in extended abstract form only. The Callovo-Oxfordian formation (COx) rock may contain up to 1% w/w of organic Carbon. Most of the Organic Matter (OM) is attached to the mineral particles whereas a small portion is present as Dissolved Organic Matter (DOM) in the pore water. In environmental studies, Natural Organic Matter (NOM) plays a key role on the bioavailability and the toxicity of metallic compounds. It is necessary to know the structure of any organic substance in order to assess which chemical and biological reactions occur under environmentally relevant conditions. The 150 Myears solid-bound organic matter of the COx (kerogen) has been already investigated in several studies and originates from a mixture of marine and terrestrial sources. In addition to this, the CCl 4 soluble organic fraction (bitumen) has been already characterized by liquid and gas chromatography coupled to mass spectrometry. It allows proportion and distribution of biological markers to be determined as polar compounds with aromatic and saturated hydrocarbons. DOM was extracted from a crushed clay rock of the COx formation with a high rock/water ratio of about 1500 g/L. Part of the OM from the COx is known to be sensitive to air oxidation which can significantly modify the nature of the bitumen by an overall shift towards lower molecular weight compounds. Therefore, the characteristics of the DOM must be determined in in-situ like conditions if one wants to assess the mobility of DOM in the clay pore space and to evaluate the mobility of heavy metals/ radionuclides. Due to their high binding capacity with metal ions and their colloidal sizes in natural waters, these macromolecules, through complexation reactions, might either enhance the mobility of trace elements, or reduce their migration rates by sorption processes in relation with their size and that of the porous medium. Consequently, the characterization of DOM in anoxic pore water samples from the COx

  20. γ-Aminobutyric Acid (GABA) Production and Angiotensin-I Converting Enzyme (ACE) Inhibitory Activity of Fermented Soybean Containing Sea Tangle by the Co-Culture of Lactobacillus brevis with Aspergillus oryzae.

    Science.gov (United States)

    Jang, Eun Kyeong; Kim, Nam Yeun; Ahn, Hyung Jin; Ji, Geun Eog

    2015-08-01

    To enhance the γ-aminobutyric acid (GABA) content, the optimized fermentation of soybean with added sea tangle extract was evaluated at 30°C and pH 5.0. The medium was first inoculated with Aspergillus oryzae strain FMB S46471 and fermented for 3 days, followed by the subsequent inoculation with Lactobacillus brevis GABA 100. After fermentation for 7 days, the fermented soybean showed approximately 1.9 g/kg GABA and exhibited higher ACE inhibitory activity than the traditional soybean product. Furthermore, several peptides in the fraction containing the highest ACE inhibitory activity were identified. The novel fermented soybean enriched with GABA and ACE inhibitory components has great pharmaceutical and functional food values.

  1. “Mais feliz que Augusto, melhor que Trajano” (Eutrópio, Breviário, viii. 5. 3): a construção do ideal de Optimus Princeps em Tácito e Plinio, o jovem.

    OpenAIRE

    FREITAS, João Victor Lanna de

    2015-01-01

    Programa de Pós-Graduação em História. Departamento de História, Instituto de Ciências Humanas e Sociais, Universidade Federal de Ouro Preto. Lanna, João Victor. “Mais feliz que Augusto, melhor que Trajano” (Eutrópio, Breviário, VIII.5.3): a construção do ideal de Optimus Princeps em Tácito e Plínio, o Jovem. João Victor Lanna de Freitas. Dissertação (Mestrado) Universidade Federal de Ouro Preto. Instituto de Ciências Humanas e Sociais. Programa de Pós-Graduação em História. Mariana, 2015....

  2. Chemical and Biological Significance of Naturally Occurring ...

    African Journals Online (AJOL)

    PROF HORSFALL

    ABSTRACT: The potassium ester (C11H23COO-K+) commonly known as African black soap was prepared by the action of palm kernel oil on cocoa pods. This was divided into four portions. Sample A contained the African Black soap without any modification, sample B was black soap modified with honey, sample C and ...

  3. Environmental applications of chemically pure natural ferrihydrite

    Czech Academy of Sciences Publication Activity Database

    Filip, J.; Zbořil, R.; Schneeweiss, Oldřich; Zeman, J.; Černík, M.; Kvapil, P.; Otyepka, M.

    2007-01-01

    Roč. 41, č. 12 (2007), s. 4367-4374 ISSN 0013-936X R&D Projects: GA MŠk 1M0512 Institutional research plan: CEZ:AV0Z20410507 Keywords : hydrous ferric-oxide * acid - mine drainage * iron-oxide Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 4.363, year: 2007

  4. Natural radionuclides from U-238 and Th-232 series and inorganic chemical characterization of soil profiles and sediment cores of the TaiaÇUpeba Reservoir, SÃO Paulo, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Souza, J.M.; Damatto, S.R.; Surkov, A.M.; Silva, A.R.; Maduar, M.F.; Gonçalves, P.N., E-mail: jmarques@ipen.br, E-mail: damatto@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil); Leonardo, L. [Centro Universitário São Camilo (Campus Ipiranga), São Paulo, SP (Brazil)

    2017-07-01

    Taiaçupeba reservoir, located in the state of São Paulo, Brazil, belongs to Producer System of Alto Tietê (Sistema Produtor Alto Tietê) and it is responsible for water supply for about 3.1million of people. The water quality of a reservoir is very important, but this is reduced by the increase of environmental degradation of the soil around the reservoir and its different uses. The study of soil profiles and sediment cores is an important tool for understanding the geophysical and geochemical aspects of an aquatic ecosystem. The objective of this work was to present the natural radionuclides {sup 238}U, {sup 226}Ra, {sup 210}Pb, {sup 232}Th, {sup 228}Th,{sup 228}Ra and {sup 40}K activity concentrations and also the inorganic chemical characterization of four soil profiles and four sediment cores collected in the area of influence area of Taiaçupeba reservoir. The analytical techniques, gamma spectrometry and instrumental neutron activation analysis were used in the determination. In the soil profiles the highest activity concentrations were obtained for the radionuclides {sup 40}K and {sup 228}Th and the lowest for {sup 210}Pb; in the sediment cores the highest activity concentrations were obtained for the radionuclide {sup 210}Pb and the lowest for {sup 226}Ra and {sup 228}Ra. For the inorganic chemical characterization the highest values obtained were for Na, As and Sb; in a sediment core a very high concentration was obtained for the element Zn indicating a probable accumulation of this element inside the reservoir; enrichment factor was used to evaluate a possible anthropic contamination in the soil and sediment at the margins of Taiaçupeba reservoir. (author)

  5. Natural radionuclides from U-238 and Th-232 series and inorganic chemical characterization of soil profiles and sediment cores of the TaiaÇUpeba Reservoir, SÃO Paulo, Brazil

    International Nuclear Information System (INIS)

    Souza, J.M.; Damatto, S.R.; Surkov, A.M.; Silva, A.R.; Maduar, M.F.; Gonçalves, P.N.; Leonardo, L.

    2017-01-01

    Taiaçupeba reservoir, located in the state of São Paulo, Brazil, belongs to Producer System of Alto Tietê (Sistema Produtor Alto Tietê) and it is responsible for water supply for about 3.1million of people. The water quality of a reservoir is very important, but this is reduced by the increase of environmental degradation of the soil around the reservoir and its different uses. The study of soil profiles and sediment cores is an important tool for understanding the geophysical and geochemical aspects of an aquatic ecosystem. The objective of this work was to present the natural radionuclides 238 U, 226 Ra, 210 Pb, 232 Th, 228 Th, 228 Ra and 40 K activity concentrations and also the inorganic chemical characterization of four soil profiles and four sediment cores collected in the area of influence area of Taiaçupeba reservoir. The analytical techniques, gamma spectrometry and instrumental neutron activation analysis were used in the determination. In the soil profiles the highest activity concentrations were obtained for the radionuclides 40 K and 228 Th and the lowest for 210 Pb; in the sediment cores the highest activity concentrations were obtained for the radionuclide 210 Pb and the lowest for 226 Ra and 228 Ra. For the inorganic chemical characterization the highest values obtained were for Na, As and Sb; in a sediment core a very high concentration was obtained for the element Zn indicating a probable accumulation of this element inside the reservoir; enrichment factor was used to evaluate a possible anthropic contamination in the soil and sediment at the margins of Taiaçupeba reservoir. (author)

  6. Siderophores of Stenotrophomonas maltophilia: detection and determination of their chemical nature Sideróforos de Stenotrophomonas maltophilia: detección y determinación de su naturaleza química

    Directory of Open Access Journals (Sweden)

    Carlos A. García

    2012-09-01

    Full Text Available Stenotrophomonas maltophilia is an emerging nosocomial pathogen. Despite the broad spectrum of syndromes associated with S. maltophilia infections, little is known about its virulence factors, including siderophore production. The aims of this work were to detect S. maltophilia siderophores and to determine their chemical nature. We studied 31 S. maltophilia isolates from device-associated infections, recovered over the period 2006-2011 at Hospital de Clínicas José de San Martin, Buenos Aires, Argentina, and the strain K279a, whose genome has been fully sequenced. The production of siderophores was screened by the chrome azurol S (CAS agar assay, previously modified to detect siderophores in this species. When grown on modified CAS agar plates, all the clinical isolates and K279a were CAS-positive for siderophore production. In order to determine the chemical nature of siderophores, the Csáky (hydroxamate-type and Arnow (catechol-type assays were used. All S. maltophilia isolates produced catechol-type siderophores, but hydroxamate-type siderophores were not detected.Stenotrophomonas maltophilia es un patógeno nosocomial emergente. A pesar de la variedad de infecciones que produce, poco se conoce acerca de sus factores de virulencia, incluida la producción de sideróforos. Nuestros objetivos fueron detectar sideróforos de S. maltophilia y determinar su naturaleza química. Se estudiaron 31 aislamientos provenientes de infecciones asociadas al uso de dispositivos médicos y la cepa K279a, cuyo genoma ha sido completamente secuenciado. Los aislamientos provenientes de infecciones se obtuvieron de pacientes asistidos en el Hospital de Clínicas José de San Martín (Buenos Aires, Argentina en el período 2006- 2011. Como método de tamizaje se empleó la técnica chrome azurol S (CAS en placa, luego de implementar una modificación para detectar sideróforos en esta especie. Dicha modificación permitió detectar la producción de sider

  7. Chemical ecology of fungi.

    Science.gov (United States)

    Spiteller, Peter

    2015-07-01

    Fungi are widespread in nature and have conquered nearly every ecological niche. Fungi occur not only in terrestrial but also in freshwater and marine environments. Moreover, fungi are known as a rich source of secondary metabolites. Despite these facts, the ecological role of many of these metabolites is still unknown and the chemical ecology of fungi has not been investigated systematically so far. This review intends to present examples of the various chemical interactions of fungi with other fungi, plants, bacteria and animals and to give an overview of the current knowledge of fungal chemical ecology.

  8. CHEMICAL EVOLUTION

    Energy Technology Data Exchange (ETDEWEB)

    Calvin, Melvin

    1965-06-01

    How did life come to be on the surface of the earth? Darwin himself recognized that his basic idea of evolution by variation and natural selection must be a continuous process extending backward in time through that period in which the first living things arose and into the period of 'Chemical Evolution' which preceded it. We are approaching the examination of these events by two routes. One is to seek for evidence in the ancient rocks of the earth which were laid down prior to that time in which organisms capable of leaving their skeletons in the rocks to be fossilized were in existence. This period is sometime prior to approximately 600 million years ago. The earth is believed to have taken its present form approximately 4700 million years ago. We have found in rocks whose age is about 1000 million years certain organic molecules which are closely related to the green pigment of plants, chlorophyll. This seems to establish that green plants were already fluorishing prior to that time. We have now found in rocks of still greater age, namely, 2500 million years, the same kinds of molecules mentioned above which can be attributed to the presence of living organisms. If these molecules are as old as the rocks, we have thus shortened the time available for the generation of the complex biosynthetic sequences which give rise to these specific hydrocarbons (polyisoprenoids) to less than 2000 million years.

  9. Chemical Peels

    Science.gov (United States)

    ... for Every Season How to Choose the Best Skin Care Products In This Section Dermatologic Surgery What is dermatologic ... for Every Season How to Choose the Best Skin Care Products Chemical Peels Uses for Chemical Peels Learn more ...

  10. Chemical Oscillations

    Indian Academy of Sciences (India)

    IMTECH),. Chandigarh. Praveen Kumar is pursuing his PhD in chemical dynamics at. Panjab University,. Chandigarh. Keywords. Chemical oscillations, autoca-. talYSis, Lotka-Volterra model, bistability, hysteresis, Briggs-. Rauscher reaction.

  11. Chemical ecotoxicology

    International Nuclear Information System (INIS)

    Paasivirta, J.

    1991-01-01

    This book discusses risk assessment, chemical cycles, structure-activity relations, organohalogens, oil residues, mercury, sampling and analysis of trace chemicals, and emissions from the forestry industry. Topics include: Cycles of chemicals in the environment. Rick assessment and management, strucuture and toxicity, sampling and analysis of trace chemicals in environment, interpretation of the environmental analysis results, mercury in the environment, organohalogen compounds in the environment, emissions from forestry industry, oil residues in the environment: oil spills in the marine environment

  12. Anatomía arterial de los colgajos musculares de extensor carpi radialis longus y extensor carpi radialis brevis para su uso en transferencia muscular funcional libre Arterial anatomy of the extensor carpi radialis longus and extensor carpi radialis brevis muscle flaps related to its use in free functioning muscle transfer

    Directory of Open Access Journals (Sweden)

    A. Rodríguez Lorenzo

    2008-09-01

    Full Text Available El objetivo de este trabajo es documentar el aporte arterial y el patrón vascular intramuscular de los músculos Extensor Carpi Radialis Longus (ECRL y Extensor Carpi Radialis Brevis (ECRB para analizar su utilización como colgajos libres en transferencia muscular funcional para reanimación facial. Realizamos un estudio anatómico en 29 brazos humanos en fresco. Las técnicas de inyección utilizadas fueron la modificada de oxido de plomo y gelatina en 11 cadáveres y la de inyección pulsátil de látex color en 18. Disecamos los músculos ECRL y ECRB y sus pedículos, los fotodocumentamos y radiografiamos valorando los resultados en función del patrón vascular intramuscular, relaciones anatómicas, calibres y longitud de pedículos. Encontramos dos patrones vasculares diferentes en las 29 disecciones siguiendo la clasificación de Mathes y Nahai de la anatomía vascular de los músculos (en función del número de pedículos vasculares y su dominancia: Tipo I( 37,9% ECRL y 20,7% ECRB y Tipo II(62,1% del ECRL y 79,3% del ECRB. El pedículo principal del ECRL (de diámetro medio 1,73 mm y longitud de pedículo media de 32,32 mm es en el 100% de los casos rama de la arteria recurrente radial y el pedículo principal del ECRB (de diámetro medio 1,11 mm y longitud de pedículo media de 27,77 mm es rama de la arteria radial en el 68,9% de los casos y de la arteria recurrente radial en el 31,1% de los casos. Concluimos que El ECRL y ECRB presentan dos tipos de patrones vasculares: tipo I y tipo II, siendo más frecuente en nuestro trabajo el tipo II, que hacen que ambos puedan ser transferidos como colgajos libres por su pedículo principal. Ambos músculos presentan un tamaño, contorno, contenido fascial importante para el anclaje de suturas y una longitud de pedículo y calibre vascular adecuados para su transferencia microvascular libre en reanimación facial. De los dos, el más realizable como colgajo libre es el ECRB ya que la relaci

  13. Chemical sensor

    Science.gov (United States)

    Rauh, R. David (Inventor)

    1990-01-01

    A sensor for detecting a chemical substance includes an insertion element having a structure which enables insertion of the chemical substance with a resulting change in the bulk electrical characteristics of the insertion element under conditions sufficient to permit effective insertion; the change in the bulk electrical characteristics of the insertion element is detected as an indication of the presence of the chemical substance.

  14. Effect of the natural and artificial drying of leaf biomass Piper hispidinervum on the chemical composition of the essential oilEfeito da secagem natural e artificial da biomassa foliar de Piper hispidinervum na composição química do óleo essencial

    Directory of Open Access Journals (Sweden)

    Marília Pereira Machado

    2013-03-01

    Full Text Available Piper hispidinervum C.DC. is a plant native to the Amazon region, produces an essential oil rich in safrole. The aim of this study was to evaluate the effect of different methods of drying biomass in chemical composition of the essential oil of P. hispidinervum cultivated in Morretes (PR. The treatments were: fresh leaves; natural drying for 6 and 12 days; oven drying at 40°C for 6 and 12 days. The essential oil was extracted by hydrodistillation from samples of 50 g of each treatment in triplicate. The chemical composition of essential oil was performed by gas chromatography coupled to mass spectrometer (GC/ MS. The experimental design was completely randomized design with three replication and four plants per plot. Data were subjected to analysis of variance. The type and drying time changes the chemical composition of the essential oil of P. hispidinervum. The dried at 40°C for 12 days reduce the amount of essential oil components, but with increasing content of safrole. Piper hispidinervum C.DC. é uma planta nativa da Amazônia, produtora de óleo essencial rico em safrol. O objetivo do presente trabalho foi avaliar o efeito de diferentes métodos de secagem da biomassa folia de pimenta longa (P. hispidinervum, cultivada em Morretes (PR, na composição química do óleo essencial. Os tratamentos avaliados foram: folhas frescas; secagem natural por 6 e 12 dias; secagem em estufa à 40°C por 6 e 12 dias. O óleo essencial foi extraído por hidrodestilação a partir de amostras de 50 g de cada tratamento em triplicata. A determinação da composição química do óleo essencial foi realizada por cromatografia gasosa acoplada ao espectrômetro de massa (GC/MS. O delineamento experimental foi inteiramente casualizado, com três repetições e quatro plantas por parcela. Os dados obtidos foram submetidos à análise de variância. O tipo e tempo de secagem alteram a constituição química do óleo essencial de pimenta-longa. A secagem em

  15. FY 1998 annual report on the research on the possibility of introducing a usable chemical substance manufacturing system by utilizing natural gas containing CO2; CO{sub 2} gan'yu tennen gas den katsuyo ni yoru yuyo kagaku busshitsu seizo system donyu kanosei ni kansuru chosa kenkyu 1998 nendo chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    The trends of effective use of gas containing CO2 from natural gas fields are surveyed, and usable chemical substance manufacturing systems which utilize natural energy are investigated, evaluated and analyzed, to extract promising systems for effective use of CO2-containing natural gas and thereby to promote its effective use. Chapter 1 outlines possibility of integrated use of gas containing CO2 from natural gas fields and natural gas energy. Chapter 2 describes the research trends in the CO2 conversion reactions for using unexploited CO2 as the carbon source. Chapter 3 describes natural energy utilization technology applicable to gas containing CO2 from natural gas fields. Chapter 4 describes performance of chemical manufacturing systems utilizing natural gas containing CO2. The energy balances and CO2 emission coefficients are estimated, based on the above. The evaluation is implemented in the order of (1) conventional steam reforming, (2) steam reforming in which heat is supplied by a solar furnace, (3) examination of the exhaust gases from a methanol synthesis process, and (4) examination of CO2-mixed reforming. Chapter 5 describes summary and proposals. (NEDO)

  16. FY 1998 annual report on the research on the possibility of introducing a usable chemical substance manufacturing system by utilizing natural gas containing CO2; CO{sub 2} gan'yu tennen gas den katsuyo ni yoru yuyo kagaku busshitsu seizo system donyu kanosei ni kansuru chosa kenkyu 1998 nendo chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    The trends of effective use of gas containing CO2 from natural gas fields are surveyed, and usable chemical substance manufacturing systems which utilize natural energy are investigated, evaluated and analyzed, to extract promising systems for effective use of CO2-containing natural gas and thereby to promote its effective use. Chapter 1 outlines possibility of integrated use of gas containing CO2 from natural gas fields and natural gas energy. Chapter 2 describes the research trends in the CO2 conversion reactions for using unexploited CO2 as the carbon source. Chapter 3 describes natural energy utilization technology applicable to gas containing CO2 from natural gas fields. Chapter 4 describes performance of chemical manufacturing systems utilizing natural gas containing CO2. The energy balances and CO2 emission coefficients are estimated, based on the above. The evaluation is implemented in the order of (1) conventional steam reforming, (2) steam reforming in which heat is supplied by a solar furnace, (3) examination of the exhaust gases from a methanol synthesis process, and (4) examination of CO2-mixed reforming. Chapter 5 describes summary and proposals. (NEDO)

  17. Chemical modification of wood

    Science.gov (United States)

    Roger M. Rowell

    2007-01-01

    After millions of years of evolution, wood was designed to perform in a wet environment, and nature is programmed to recycle it, in a timely way, back to the basic building blocks of carbon dioxide and water through biological, thermal, aqueous, photochemical, chemical, and mechanical degradation. The properties of wood are, for the most part, a result of the chemistry...

  18. Mini-open reconstruction of lateral collateral ligaments of ankle with partial tendon of its peroneus brevis%小切口取部分腓骨短肌腱重建踝关节外侧副韧带

    Institute of Scientific and Technical Information of China (English)

    陈前博; 唐康来; 吴雪晖; 徐格; 谭晓康; 周兵华; 周运平; 许建中

    2008-01-01

    Objective To describe a new technique with mini-open reconstruction of lateral ligaments of ankle with partial tendon of its peroneus brevis and evaluate its effect in treatment of chronic lateral ankle instability. Methods A total of 11 cases of chronic lateral ankle instability;at mean age of 27.6 years(16-42 years),were treated with mini-open reconstruction of the lateral ligaments of the ankle with partial tendon of its peroneus brevis.The mean delay between the initial episode of ankle sprain and the surgery was 10.3 months(4-32 months).Postoperatively,all cases were examined with MRI,stress X-rays and comparative stability of bilateral ankle inspection at clinical follow-up.The function of the ankle were evaluated bv American Orthopaedic Foot & Ankle Society (AOFAS)score and ankle-hind foot scale. Results The average duration of follow-up was 17.5 months(12-37 months).The mean AOFAS ankle-hindfoot score was 88.3 points(72-96 points)at the time of the latest follow-up,including excellent result in 6 cases(55%),good in 4(36%)and fair in 1(9%).MRI results showed that the ruptured lateral collateral ligaments of the ankle were repaired and remodeled very well in all patients.There was no recurrence of the ankle instability or other complications. Conclusion Mini-open reconstruction of the lateral ligaments of ankle with partial tendon of its peroneus brevis is safe and effective for treatment of chronic lateral ankle instability.%目的 介绍小切口取部分腓骨短肌腱解剖重建外侧副韧带治疗慢性踝关节外侧不稳的疗效.方法 11例慢性踝关节外侧不稳患者接受小切口取部分腓骨短肌腱解剖重建踝关节外侧副韧带的手术治疗,年龄16~42岁,平均27.6岁.术前病程4~32个月,平均10.3个月.术后定期行双侧踝关节对比稳定检查、应力位X线片及MRI检查,并按美国足踝外科协会(AOFAS)踝-后足功能评分表进行功能评分.结果 11例患者术后平均随访17.5个月(12~37

  19. [Chemical weapons and chemical terrorism].

    Science.gov (United States)

    Nakamura, Katsumi

    2005-10-01

    Chemical Weapons are kind of Weapons of Mass Destruction (WMD). They were used large quantities in WWI. Historically, large quantities usage like WWI was not recorded, but small usage has appeared now and then. Chemical weapons are so called "Nuclear weapon for poor countrys" because it's very easy to produce/possession being possible. They are categorized (1) Nerve Agents, (2) Blister Agents, (3) Cyanide (blood) Agents, (4) Pulmonary Agents, (5) Incapacitating Agents (6) Tear Agents from the viewpoint of human body interaction. In 1997 the Chemical Weapons Convention has taken effect. It prohibits chemical weapons development/production, and Organization for the Prohibition of Chemical Weapons (OPCW) verification regime contributes to the chemical weapons disposal. But possibility of possession/use of weapons of mass destruction by terrorist group represented in one by Matsumoto and Tokyo Subway Sarin Attack, So new chemical terrorism countermeasures are necessary.

  20. Avaliação da composição química de milho seco e armazenado em silo tipo alambrado com ar natural forçado Evaluation of chemical composition of corn dried and stored with forced natural air

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Gutkoski

    2009-12-01

    Full Text Available O trabalho objetivou estudar o efeito da umidade de colheita e do tempo de armazenamento em grãos de milho secos e armazenados em silos com ar natural forçado. Grãos de milho colhidos com 17,8; 18,9 e 20,5% de água foram acondicionados em silos tipo alambrado com fundo falso perfurado e com ventiladores ligados ininterruptamente até a secagem. Amostras de milho foram coletadas nos tempos zero, 4, 8, 22 e 112 dias, em seis alturas de camada de cada silo (10, 60, 110, 160, 210 e 260 cm. A composição química foi determinada pelo uso de Espectrofotômetro do Infravermelho Proximal (NIR e os resultados expressos em porcentagem e em base seca. Os dados foram analisados estatisticamente (Anova e nas interações significativas, elaborados os gráficos de regressão. Nas determinações de proteínas, lipídios, matéria seca e fibra em detergente neutro as interações foram significativas ao nível de 5% de probabilidade de erro, enquanto que em cinzas, umidade e carboidratos não foram verificadas diferenças significativas. A aeração natural forçada é capaz de reduzir a umidade do milho para 13%, sendo tecnicamente viável em propriedades familiares.The aim of this work was to study the effects of moisture at harvest and time of storage upon grains of corn dried and stored in bins with forced natural air. Grains of corn harvested with 17.8; 18.9, and 20.5% of water were stored in drying bins with false floor with fans working full-time until drying. Samples of corn were collected at zero, 4, 8, 22, and 112 days from six different heights in each bin (10, 60, 110, 160, 210 and 260 cm. The chemical composition was determined through Near-Infrared Spectrophotometer (NIR and the results were expressed in percentage at dry basis. The data were statistically analyzed (Anova and for the significant interactions graphics of regression were provided. In the process of determination of protein, fat, dry matter, and neutral detergent fiber the

  1. Volatile chemical interaction between undamaged plants

    OpenAIRE

    Glinwood, Robert

    2010-01-01

    This chapter discusses whether plant chemical communication is a mechanism by which plant genetic diversity can affect the natural enemies of herbivores. Plant genetic diversity influences natural enemies, and these insects use volatile chemical cues to locate suitable habitats. However, the importance of chemical communication for these interactions has not been considered. In this chapter, the latest research on chemical communication between undamaged plants is reviewed. ...

  2. Chemical evolution and life

    Directory of Open Access Journals (Sweden)

    Malaterre Christophe

    2015-01-01

    Full Text Available In research on the origins of life, the concept of “chemical evolution” aims at explaining the transition from non-living matter to living matter. There is however strong disagreement when it comes to defining this concept more precisely, and in particular with reference to a chemical form of Darwinian evolution: for some, chemical evolution is nothing but Darwinian evolution applied to chemical systems before life appeared; yet, for others, it is the type of evolution that happened before natural selection took place, the latter being the birthmark of living systems. In this contribution, I review the arguments defended by each side and show how both views presuppose a dichotomous definition of “life”.

  3. Hazardous Chemicals

    Centers for Disease Control (CDC) Podcasts

    Chemicals are a part of our daily lives, providing many products and modern conveniences. With more than three decades of experience, The Centers for Disease Control and Prevention (CDC) has been in the forefront of efforts to protect and assess people's exposure to environmental and hazardous chemicals. This report provides information about hazardous chemicals and useful tips on how to protect you and your family from harmful exposure.

  4. A Chemically Modified Curcumin (CMC 2.24) Inhibits Nuclear Factor κB Activation and Inflammatory Bone Loss in Murine Models of LPS-Induced Experimental Periodontitis and Diabetes-Associated Natural Periodontitis.

    Science.gov (United States)

    Elburki, Muna S; Rossa, Carlos; Guimarães-Stabili, Morgana R; Lee, Hsi-Ming; Curylofo-Zotti, Fabiana A; Johnson, Francis; Golub, Lorne M

    2017-08-01

    The purpose of this study was to assess the effect of a novel chemically modified curcumin (CMC 2.24) on NF-κB and MAPK signaling and inflammatory cytokine production in two experimental models of periodontal disease in rats. Experimental model I: Periodontitis was induced by repeated injections of LPS into the gingiva (3×/week, 3 weeks); control rats received vehicle injections. CMC 2.24, or the vehicle, was administered by daily oral gavage for 4 weeks. Experimental model II: Diabetes was induced in adult male rats by streptozotocin injection; periodontal breakdown then results as a complication of uncontrolled hyperglycemia. Non-diabetic rats served as controls. CMC 2.24, or the vehicle, was administered by oral gavage daily for 3 weeks to the diabetics. Hemimaxillae and gingival tissues were harvested, and bone loss was assessed radiographically. Gingival tissues were pooled according to the experimental conditions and processed for the analysis of matrix metalloproteinases (MMPs) and bone-resorptive cytokines. Activation of p38 MAPK and NF-κB signaling pathways was assessed by western blot. Both LPS and diabetes induced an inflammatory process in the gingival tissues associated with excessive alveolar bone resorption and increased activation of p65 (NF-κB) and p38 MAPK. In both models, the administration of CMC 2.24 produced a marked reduction of inflammatory cytokines and MMPs in the gingival tissues, decreased bone loss, and decreased activation of p65 (NF-κB) and p38 MAPK. Inhibition of these cell signaling pathways by this novel tri-ketonic curcuminoid (natural curcumin is di-ketonic) may play a role in its therapeutic efficacy in locally and systemically associated periodontitis.

  5. Alarms, Chemical

    Science.gov (United States)

    cited in applicable qualitative materiel requirements, small development requirements, technical characteristics, and other requirements and documentation that pertain to automatic chemical agent alarms.

  6. Chemical oceanography

    National Research Council Canada - National Science Library

    Millero, F.J

    1996-01-01

    Chemical Oceanography presents a comprehensive examination of the chemistry of oceans through discussions of such topics as descriptive physical oceanography, the composition of seawater and the major...

  7. Inter-annual chemical stratification in Brazilian natural lakes: meromixis and hypolimnetic memory Estratificação química em lagos naturais brasileiros: meromixia e memória hipolimnética

    Directory of Open Access Journals (Sweden)

    Luciana Gomes Barbosa

    2012-06-01

    Full Text Available AIM: chemical stratification and the patterns of light limitation and nutrients of two natural lakes, one shallow and the other one deep, were comparatively evaluated, both lakes located in the southeast Brazil. METHODS: pH, electrical conductivity, dissolved oxygen, total dissolved solids and nutrients were monthly collected during 5 consecutive years at the vertical profile of the two lakes. RESULTS: multivariate analysis indicated that the long thermal stratification period favored the occurrence of chemical stratification in the two lakes. However, in the deeper lake the stratified thermal profile with high hypolimnetic nutrient concentration, electrical conductivity, total dissolved solids and redox potential indicated that the mixing was not complete even during the annual circulation period, suggesting a slight meromixis and a high chemical stability at the hypolimnion. In the shallower lake, high light attenuation and high availability of nitrogen forms (mainly N-NH4 and phosphorus was observed along the water column, even during stratification. In the deeper lake, N and P co-limitation and low light attenuation coefficients were detected. CONCLUSION: thermal and chemical stratification patterns indicated that the Carioca lake is a shallow, turbid, nutrient rich, whereas the Dom Helvecio lake is a deep, clear, oligotrophic system with a tendency towards meromixis and the isolation of solutes in the hypolimnion. Consequently, meromixis was compared to a "hypolimnetic memory", which was defined, in the case of the deeper lake, as the maintenance of the chemical stratification along the years, during the lake thermal circulation period.OBJETIVO: a estratificação química e os padrões de limitação por luz e nutrientes foram avaliados comparativamente em dois lagos naturais, sendo um raso e o outro profundo no sudeste do Brasil. MÉTODOS: as amostragens de pH, condutividade elétrica, oxigênio dissolvido, sólidos totais dissolvidos e

  8. Vieillissement du polyamide 11 utilisé dans les conduites flexibles : influence de la composition du fluide transporté Influence of the Chemical Nature of the Environment on the Aging of Polyamide 11 Used for Offshore Flexible Pipes

    Directory of Open Access Journals (Sweden)

    Ubrich E.

    2006-11-01

    émontrée et a pu être attribuée à certains types d'hydrocarbures dont la nature a été précisée. Les résultats obtenus ont permis de conclure que le phénomène principal mis en jeu au cours du vieillissement est une hydrolyse causée par l'eau absorbée dans le matériau et qui entraîne une coupure des chaînes macromoléculaires et la fragilisation du polymère. 3 D'étendre l'application du modèle établi avec des coupes gazoles au cas d'un vieillissement dans un pétrole brut et de vérifier son caractère prédictif. Polyamide 11 is used as a leakproof sheath inside flexible flowlines for petroleum products. Under some operating conditions, this polymer undergoes a degradation of its original physicochemical and mechanical properties, which may be assimilated with a phenomenon of aging. Material exchanges occur between polyamide 11 and the fluid transported. The components present in the fluid (water, hydrocarbons may be absorbed, and the principal additive of the material (the plasticizer is extracted. This study was carried out to determine the influence of the composition of the chemical environment of aging on the properties of polyamide 11. In the first phase, a new analysis method was developed for quantifying diffusing materials in polyamide 11. Effectively, several techniques can be used for determining such materials. However, interference problems may be encountered when the polymer is in contact with oil containing sulfur-bearing products. Likewise, none of these techniques is capable of simultaneously making a complete analysis of all the materials. The principle of the method developed consists in performing a thermodesorption of the different materials present in the polymer and in analyzing them on line by medium-resolution mass spectrometry (resolution = 3000. This resolution is also capable of determining the distribution, by chemical families, of the hydrocarbons absorbed. The method was checked with aged polyamide 11 samples containing either

  9. Chemical Emergencies - Multiple Languages

    Science.gov (United States)

    ... Chemical Emergencies - bosanski (Bosnian) PDF Chemical Emergencies - English MP3 Chemical Emergencies - bosanski (Bosnian) MP3 Chemical Emergencies - English MP4 Chemical Emergencies - bosanski (Bosnian) ...

  10. Determining physiological cross-sectional area of extensor carpi radialis longus and brevis as a whole and by regions using 3D computer muscle models created from digitized fiber bundle data.

    Science.gov (United States)

    Ravichandiran, Kajeandra; Ravichandiran, Mayoorendra; Oliver, Michele L; Singh, Karan S; McKee, Nancy H; Agur, Anne M R

    2009-09-01

    Architectural parameters and physiological cross-sectional area (PCSA) are important determinants of muscle function. Extensor carpi radialis longus (ECRL) and brevis (ECRB) are used in muscle transfers; however, their regional architectural differences have not been investigated. The aim of this study is to develop computational algorithms to quantify and compare architectural parameters (fiber bundle length, pennation angle, and volume) and PCSA of ECRL and ECRB. Fiber bundles distributed throughout the volume of ECRL (75+/-20) and ECRB (110+/-30) were digitized in eight formalin embalmed cadaveric specimens. The digitized data was reconstructed in Autodesk Maya with computational algorithms implemented in Python. The mean PCSA and fiber bundle length were significantly different between ECRL and ECRB (p < or = 0.05). Superficial ECRL had significantly longer fiber bundle length than the deep region, whereas the PCSA of superficial ECRB was significantly larger than the deep region. The regional quantification of architectural parameters and PCSA provides a framework for the exploration of partial tendon transfers of ECRL and ECRB.

  11. Synthesizing Novel Anthraquinone Natural Product-Like Compounds to Investigate Protein-Ligand Interactions in Both an in Vitro and in Vivo Assay: An Integrated Research-Based Third-Year Chemical Biology Laboratory Course

    Science.gov (United States)

    McKenzie, Nancy; McNulty, James; McLeod, David; McFadden, Meghan; Balachandran, Naresh

    2012-01-01

    A new undergraduate program in chemical biology was launched in 2008 to provide a unique learning experience for those students interested in this interdisciplinary science. An innovative undergraduate chemical biology laboratory course at the third-year level was developed as a key component of the curriculum. The laboratory course introduces…

  12. Natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Fraser, J W

    1967-08-01

    This report on the natural gas industry of Canada includes: composition and uses of natural gas, production statistics, exploration and development, reserve estimates, natural gas processing, transportation, and marketing. For the Canadian natural gas industry, 1966 was a year of moderate expansion in all phases, with a strong demand continuing for sulfur and liquid hydrocarbons produced as by-products of gas processing. Value of natural gas production increased to $199 million and ranked sixth in terms of value of mineral ouput in Canada. Currently, natural gas provides over 70% of Canada's energy requirements. Proved remaining marketable reserves are estimated to be in excess of a 29-yr supply.

  13. Hazardous Chemicals

    Centers for Disease Control (CDC) Podcasts

    2007-04-10

    Chemicals are a part of our daily lives, providing many products and modern conveniences. With more than three decades of experience, The Centers for Disease Control and Prevention (CDC) has been in the forefront of efforts to protect and assess people's exposure to environmental and hazardous chemicals. This report provides information about hazardous chemicals and useful tips on how to protect you and your family from harmful exposure.  Created: 4/10/2007 by CDC National Center for Environmental Health.   Date Released: 4/13/2007.

  14. Natural Gas

    OpenAIRE

    Bakar, Wan Azelee Wan Abu; Ali, Rusmidah

    2010-01-01

    Natural gas fuel is a green fuel and becoming very demanding because it is environmental safe and clean. Furthermore, this fuel emits lower levels of potentially harmful by-products into the atmosphere. Most of the explored crude natural gas is of sour gas and yet, very viable and cost effective technology is still need to be developed. Above all, methanation technology is considered a future potential treatment method for converting the sour natural gas to sweet natural gas.

  15. Chemical Peel

    Science.gov (United States)

    ... your expectations. Talk with your doctor about your motivations and expectations, as well as the potential risks. ... the sun permanently to prevent changes in skin color. Keep in mind that chemical peel results might ...

  16. Chemical carcinogens

    National Research Council Canada - National Science Library

    Searle, Charles E

    1976-01-01

    Cancer causing agents are now known to exist throughout the environment-in polluted air and tobacco smoke, in various plants and foods, and in many chemicals that are used in industry and laboratories...

  17. Chemical sensors

    International Nuclear Information System (INIS)

    Hubbard, C.W.; Gordon, R.L.

    1987-05-01

    The revolution in analytical chemistry promised by recent developments in the field of chemical sensors has potential for significant positive impact on both research and production activities conducted by and for the Department of Energy. Analyses which were, in the past, performed only with a roomful of expensive equipment can now be performed with miniature solid-state electronic devices or small optical probes. Progress in the development of chemical sensors has been rapid, and the field is currently growing at a great rate. In accordance, Pacific Northwest Laboratory initiated a survey of recent literature so that contributors to active programs in research on analytical methods could be made aware of principles and applications of this new technology. This report presents the results of that survey. The sensors discussed here are divided into three types: micro solid-state devices, optical sensors, and piezoelectric crystal devices. The report is divided into three corresponding sections. The first section, ''Micro Solid-State Devices,'' discusses the design, operation, and application of electronic sensors that are produced in much the same way as standard solid-state electronic devices. The second section, ''Optrodes,'' covers the design and operation of chemical sensors that use fiber optics to detect chemically induced changes in optical properties. The final section, ''Piezoelectric Crystal Detectors,'' discusses two types of chemical sensors that depend on the changes in the properties of an oscillating piezoelectric crystal to detect the presence of certain materials. Advantages and disadvantages of each type of sensor are summarized in each section

  18. PLURALIZING NATURE

    DEFF Research Database (Denmark)

    Clemmensen, Thomas Juel

    2014-01-01

    Denmark is widely recognised for its democratic approach to planning and the idea of planning for the common good. This interest in the common good and common values seems also to be reflected in the way which nature restoration is planned and managed – one common nature directed by the public...... authorities. But nature restoration is far from being a neural undertaking. Just like any other type of heritage production it can be the source of dissonance – ‘our’ nature is not necessary ‘their’ nature. Often this dissonance is managed in ways, which are not particular sensitive to site......-specificity. As exemplified by the Skjern River Restoration Project (1999-2003), one interpretation of the landscape sometimes suppresses other valid interpretations neglecting its diverse history. However, evidence from Switzerland suggests that planning for the common good, in the case of nature restoration, does...

  19. Natural Philosophy

    OpenAIRE

    Blair, Ann M.

    2006-01-01

    Natural philosophy” is often used by European historians as an umbrella term to designate the study of nature before it can easily be identified with what we call “science” today, to avoid the modern and potentially anachronistic connotations of that term. But “natural philosophy” (and its equivalents in different languages) was also an actor's category, a term commonly used throughout the early modern period and typically defined quite broadly as the study of natural bodies. As the central ...

  20. Dissonant Nature

    DEFF Research Database (Denmark)

    Clemmensen, Thomas Juel

    2013-01-01

    Nature restoration is far from being a neural undertaking. Just like any other type of heritage production it can be the source of dissonance – ‘our’ nature is not necessary ‘their’ nature. Often this dissonance is managed in ways, which are not particular sensitive to site-specificity. As exempl...... and allows for multiple interpretations to coexist. Evidence can be found in the Re-naturalization of River Aire (2002-2015), a restoration project, which reveals approaches that could be labelled landscape architecture specific....

  1. Temporal naturalism

    Science.gov (United States)

    Smolin, Lee

    2015-11-01

    Two people may claim both to be naturalists, but have divergent conceptions of basic elements of the natural world which lead them to mean different things when they talk about laws of nature, or states, or the role of mathematics in physics. These disagreements do not much affect the ordinary practice of science which is about small subsystems of the universe, described or explained against a background, idealized to be fixed. But these issues become crucial when we consider including the whole universe within our system, for then there is no fixed background to reference observables to. I argue here that the key issue responsible for divergent versions of naturalism and divergent approaches to cosmology is the conception of time. One version, which I call temporal naturalism, holds that time, in the sense of the succession of present moments, is real, and that laws of nature evolve in that time. This is contrasted with timeless naturalism, which holds that laws are immutable and the present moment and its passage are illusions. I argue that temporal naturalism is empirically more adequate than the alternatives, because it offers testable explanations for puzzles its rivals cannot address, and is likely a better basis for solving major puzzles that presently face cosmology and physics. This essay also addresses the problem of qualia and experience within naturalism and argues that only temporal naturalism can make a place for qualia as intrinsic qualities of matter.

  2. The detection of the capsular tear at the undersurface of the extensor carpi radialis brevis tendon in chronic tennis elbow: the value of magnetic resonance imaging and computed tomography arthrography.

    Science.gov (United States)

    Sasaki, Koichi; Tamakawa, Mitsuharu; Onda, Kazunori; Iba, Kosuke; Sonoda, Tomoko; Yamashita, Toshihiko; Wada, Takuro

    2011-04-01

    This study compared the diagnostic efficacy of magnetic resonance imaging (MRI) and computed tomography arthrography (CTA) in the assessment of capsular tears at the undersurface of the extensor carpi radials brevis tendon in chronic tennis elbow using arthroscopy as a gold standard. Because of the higher spatial resolution of CT, we hypothesized that CTA is superior to MRI for assessing capsular tears. We retrospectively reviewed 19 consecutive patients with chronic tennis elbow with preoperative MRI and CTA studies who underwent arthroscopic surgery. Three observers with different levels of training and experience (musculoskeletal radiologist, experienced elbow surgeon, and hand fellow) evaluated the capsular tear by MRI and CTA in a blinded manner. The results of the MRI and CTA were compared and the agreement among the 3 observers was determined using an intraclass correlation coefficient (ICC). Then, the results of the MRI and CTA examinations were compared with the intraoperative findings of the arthroscopic examination. The sensitivity, specificity, and κ value were calculated. The ICC of CTA (0.855) was superior to MRI (0.645). The sensitivity, specificity, and κ value of CTA were superior to those of MRI in each of the 3 observers. The κ value was 0.79, 0.89, and 0.79 for CTA, and 0.48, 0.48, and 0.27 for MRI for the radiologist, surgeon, and fellow, respectively. CTA was a reliable and accurate diagnostic modality compared with MRI to detect the capsular tear in patients with chronic tennis elbow. CTA was less influenced by the observer's experience. Copyright © 2011 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  3. Effect of simultaneous stretching of the wrist and finger extensors for lateral epicondylitis: a gross anatomical study of the tendinous origins of the extensor carpi radialis brevis and extensor digitorum communis.

    Science.gov (United States)

    Shirato, Rikiya; Wada, Takuro; Aoki, Mitsuhiro; Iba, Kousuke; Kanaya, Kohei; Fujimiya, Mineko; Yamashita, Toshihiko

    2015-11-01

    Pulling the wrist into flexion with the elbow in extension and forearm in pronation has been used as the stretching technique of wrist extensors for lateral epicondylitis. Simultaneous stretching of the fingers in addition to the wrist flexion has also been applied. However, the mechanism of this simultaneous stretching has not been clarified. This study is designed to clarify the mechanism underlying this simultaneous stretching technique based on the anatomical features of the origins of the extensor carpi radialis brevis (ECRB) and extensor digitorum communis (EDC). Thirty-nine arms from formalin-embalmed Japanese human specimens were dissected. The features of the origins of the ECRB and EDC were macroscopically observed, and the locations of each origin on the lateral epicondyle were measured. The ECRB had a long and wide, purely tendinous origin which originated from the anterior slope of the lateral epicondyle. The tendinous origin of the index finger of the EDC (EDC-IF) arose from the posterior aspect of the ECRB tendinous origin, with a coexisting muscular portion observed at the level of the proximal forearm. The middle finger of the EDC (EDC-MF) had a short tendinous origin with an associated muscular portion and originated proximo-laterally to the origin of the ECRB on the lateral epicondyle. In addition, the muscular origin of the EDC-MF arose on the superficial and posterior aspect of the ECRB tendinous origin. In contrast, the ring and little fingers of the EDC originated from the tendinous septum of the extensor digiti minimi and extensor carpi ulnaris, and had no connection with the ECRB tendinous origin. On the basis of our anatomical findings, simultaneous stretching of the wrist extensors by wrist, index and middle fingers flexion could provide stretching force to both the tendinous origins of the ECRB and EDC through the EDC-IF and EDC-MF.

  4. Chemical behaviour of trivalent and pentavalent americium in saline NaCl-solutions. Studies of transferability of laboratory data to natural conditions. Interim report. Reported period: 1.2.1993-31.12.1993

    International Nuclear Information System (INIS)

    Runde, W.; Kim, J.I.

    1994-09-01

    In order to clarify the chemical behaviour of Americium in saline aqueous systems relevant for final storage this study deals with the chemical reactions of trivalent and pentavalent Americium in NaCl-solutions under the influence of radiolysis from its own alpha radiation. The focus of the study was on investigating the geologically relevant reactions, such as hydrolysis or carbonate- and chloride complexing in solid-liquid equilibriums. Comprehensive measurements on solubility and spectroscopic studies in NaCl-solutions were carried out in a CO 2 -free atmosphere and 10 -2 atm CO 2 partial pressure. Identification and characterisation of the AM (III) and AM(V) solid phases were supplemented by structural research with the chemically analogue EU (III) and Np(V) compounds. The alpha-radiation induced radiolysis in saline NaCl solutions and the redox behaviour of Americium which was influenced thereby were spectroscopically quantified. (orig.) [de

  5. Chemical pneumonitis

    Science.gov (United States)

    ... cleaning materials such as chlorine bleach, during industrial accidents, or near swimming pools) Grain and fertilizer dust ... and the A.D.A.M. Editorial team. Chemical Emergencies ... about A.D.A.M.'s editorial policy , editorial process and privacy policy . A.D.A.M. is ...

  6. Chemical dispersants

    NARCIS (Netherlands)

    Rahsepar, Shokouhalsadat; Smit, Martijn P.J.; Murk, Albertinka J.; Rijnaarts, Huub H.M.; Langenhoff, Alette A.M.

    2016-01-01

    Chemical dispersants were used in response to the Deepwater Horizon oil spill in the Gulf of Mexico, both at the sea surface and the wellhead. Their effect on oil biodegradation is unclear, as studies showed both inhibition and enhancement. This study addresses the effect of Corexit on oil

  7. Chemical Graph Transformation with Stereo-Information

    DEFF Research Database (Denmark)

    Andersen, Jakob Lykke; Flamm, Christoph; Merkle, Daniel

    2017-01-01

    Double Pushout graph transformation naturally facilitates the modelling of chemical reactions: labelled undirected graphs model molecules and direct derivations model chemical reactions. However, the most straightforward modelling approach ignores the relative placement of atoms and their neighbo......Double Pushout graph transformation naturally facilitates the modelling of chemical reactions: labelled undirected graphs model molecules and direct derivations model chemical reactions. However, the most straightforward modelling approach ignores the relative placement of atoms...... and their neighbours in space. Stereoisomers of chemical compounds thus cannot be distinguished, even though their chemical activity may differ substantially. In this contribution we propose an extended chemical graph transformation system with attributes that encode information about local geometry. The modelling...... of graph transformation, but we here propose a framework that also allows for partially specified stereoinformation. While there are several stereochemical configurations to be considered, we focus here on the tetrahedral molecular shape, and suggest general principles for how to treat all other chemically...

  8. Changes in amino acid profile of alfalfa silage preserved by chemical and biological additives during fermentation

    Directory of Open Access Journals (Sweden)

    Jaroslava Michálková

    2009-01-01

    Full Text Available Changes in amino acid profile of alfalfa silage preserved with chemical or biological additives were studied in fresh and wilted silage. The chemical additive was formic acid and the biological additive consisted of Lactobacillus rhamnosus, L. plantarum, L. brevis, L. buchneri and Pediococcus pentosaceus. Second cut alfalfa (Medicago sativa L. was harvested at the bloom stage, ensiled in mini silos (15 dm3 and fermented at 20–23 °C for 12 weeks. The dry matter of the fresh silage was 228 g . kg−1 and 281.6 g . kg−1 for the wilted before ensiling. The amino acid content was estimated by using an automatic amino acid analyzer AAA (INGOS Prague. The results of the experiments indicated that amino acid breakdown was inhibited by increased dry matter and the use of chemical and biological additive. Additionally, the content of amino acids was found to change in relation to the degree of wilting and formic acid treatment yielded the lowest amino acid breakdown. The amino acid breakdown was also reduced by biological preservative especially in the silage with a higher level of dry matter content.

  9. Matematica Natural.

    Science.gov (United States)

    Lozano, Patricia; Medearis, Linda

    Matematica Natural (Natural Mathematics) is a mathematics curriculum for young children based on the assumption that they learn mathematics through concrete, real life, relevant experiences and that educational differences rather than cultural differences influence math achievement. The curriculum uses hands-on materials and activities to teach…