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Sample records for brevis natural chemical

  1. Harmful algal toxins of the Florida red tide (Karenia brevis): natural chemical stressors in South Florida coastal ecosystems

    OpenAIRE

    Pierce, R. H.; Henry, M S

    2008-01-01

    The Florida red tide is a descriptive name for high concentrations of the harmful marine alga, Karenia brevis. Although most prevalent along the south-west Florida coast, periodic blooms have occurred throughout the entire US and Mexico Gulf coasts and the Atlantic coast to North Carolina. This dinoflagellate produces a suite of polyether neurotoxins, called brevetoxins, that cause severe impacts to natural resources, as well as public health. These naturally produced biotoxins may represent ...

  2. 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...... vulnerability to the toxicant which acts in a size selective manner. Moreover, population vulnerability to the toxicant increases with predator size and predation intensity whereas indirect trait-mediated interactions via predator kairomones may buffer chemical effects to a certain extent. Our study...... 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...

  3. 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...... vulnerability to the toxicant which acts in a size selective manner. Moreover, population vulnerability to the toxicant increases with predator size and predation intensity whereas indirect trait-mediated interactions via predator kairomones may buffer chemical effects to a certain extent. Our study...

  4. 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.

  5. [Demodex folliculorum and demodex brevis].

    Science.gov (United States)

    Marcinowska, Zuzanna; Kosik-Bogacka, Danuta; Lanocha-Arendarczyk, Natalia; Czepita, Damian; Lanocha, Aleksandra

    2015-01-01

    Demodex are cosmopolitan mites occurring in many species of mammals. Two morphologically distinct Demodex species parasitize on humans: Demodexfolliculorum (Simon, 1842) and Demodex brevis (Akbulatova, 1963). Until recently, these species have been regarded as commensals; now they are considered as parasitic organisms. In people, Demodex spp. can be found mainly in the sebaceous glands of the skin (mainly in the area of the forehead, cheeks, nose, behind ears and neck), in hearing aids, and on the scalp, covered with hair. Infection with demodex happens through direct contact with infected bed linen, towels, creams and other cosmetics. Despite the high prevalence of Demodex spp. in the human population, symptoms of demodecosis are not common, and can be found mainly in people with weakened immune systems due to aging or a number of diseases. PMID:27116866

  6. Inhibitory mechanism of phthalate esters on Karenia brevis.

    Science.gov (United States)

    Liu, Ning; Wen, Fuling; Li, Fengmin; Zheng, Xiang; Liang, Zhi; Zheng, Hao

    2016-07-01

    The occurrence of phthalate esters (PAEs), a class of widely used and environmentally prevalent chemicals, raises concern to environmental and human health globally. The PAEs have been demonstrated to inhibit algae growth, but the underlying mechanisms remain unclear. In this research, diethyl ortho-phthalate (DEP), diallyl phthalate (DAP), di-n-butyl ortho-phthalate (DBP), di-iso-butyl ortho-phthalate, and benzyl-n-butyl ortho-phthalate (BBP) were screened from 11 species of PAEs to study their inhibitory effects on Karenia brevis and determine their target sites on algae. With increasing the alkyl chains of these five PAEs, the values of EC50,96h decreased. The content of malondialdehyde increased with the continuous accumulation of reactive oxygen species (ROS) in the algae cells. Moreover, the superoxide dismutase and catalase contents were first activated and then inhibited. The ultrastructures of Karenia brevis cells were detected by transmission electron microscopy, and cells treated with PAEs exhibiting distorted shapes and large vacuoles. Thus, the algae were damaged by ROS accumulation, resulting in lipid oxidation and algal growth inhibition. The inhibitors of the electron transport chain showed that the sites of ROS production and accumulation in K. brevis cells under DEP and BBP were the mitochondria and chloroplast, respectively. Moreover, the target sites of DAP and DBP were both the chloroplast and mitochondria. These results are useful for controlling PAEs contamination in and revealing the fate of PAEs in aquatic ecosystem. PMID:27151426

  7. Chemical osmosis in natural clayey materials

    NARCIS (Netherlands)

    Keijzer, T.J.S.

    2000-01-01

    Semipenneable properties of clayey natural materials can have a significant impact on a range of geological and geochemical processes on laboratory and field scale. The importance of chemical osmosis in semipenneable natural clays for transport of contaminants was first discussed in the Netherlands

  8. Natural radiation, nuclear wastes and chemical pollutants

    International Nuclear Information System (INIS)

    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

  9. Storage features of Lactobacillus Brevis strain 9

    Directory of Open Access Journals (Sweden)

    Utemurat Sagyndykov

    2013-03-01

    Full Text Available Current article presents the results of the research conducted on storing lactic bacteria. On the basis of results of experiments on liophilization of the culture of lactic bacteria Lactobacillus brevis strain №9, it has been concluded that the optimum way of storing the given culture is the method of liophilic drying with the vacuum soldering.

  10. Chemical deacetylation natural xanthan (Jungbunzlauer®)

    OpenAIRE

    Ellen P. Pinto; Lígia Furlan; Claire T. Vendruscolo

    2011-01-01

    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 ...

  11. Effects of the dinoflagellate Karenia brevis on larval development in three species of bivalve mollusc from Florida.

    Science.gov (United States)

    Leverone, Jay R; Blake, Norman J; Pierce, Richard H; Shumway, Sandra E

    2006-07-01

    The effects of Karenia brevis (Wilson clone) on larval survival and development of the northern quahog, Mercenaria mercenaria, eastern oyster, Crassostrea virginica and bay scallop, Argopecten irradians, were studied in the laboratory. Larvae were exposed to cultures of whole and lysed cells, with mean total brevetoxin concentrations of 53.8 and 68.9 microgL(-1), respectively. Survival of early (3-day-old) larvae was generally over 85% for all shellfish species at K. brevis densities of 100 cells ml(-1) or less, and not significantly different between whole and lysed culture. At 1000 cells ml(-1), survival was significantly less in lysed culture than whole culture for both M. mercenaria and C. virginica. Survival of late (7-day-old) larvae in all three species was not significantly affected by K. brevis densities of 1000 cells ml(-1) or less. At 5000 cells ml(-1), however, survival was reduced to 37%, 26% and 19% for A. irradians, M. mercenaria and C. virginica, respectively. Development of C. virginica and M. mercenaria larvae was protracted at K. brevis densities of 1000 cells ml(-1). These results suggest that blooms of K. brevis, and particularly their associated brevetoxins, may have detrimental consequences for Florida's shellfisheries by disrupting critical larval processes. Special attention should be paid to blooms of K. brevis where these shellfish occur naturally or where aquaculture and restoration activities are either ongoing or planned.

  12. Antitumor activity of chemical modified natural compounds

    Directory of Open Access Journals (Sweden)

    Marilda Meirelles de Oliveira

    1991-01-01

    Full Text Available Search of new activity substances starting from chemotherapeutic agents, continously appears in international literature. Perhaps this search has been done more frequently in the field of anti-tumor chemotherapy on account of the unsuccess in saving advanced stage patients. The new point in this matter during the last decade was computer aid in planning more rational drugs. In near future "the accessibility of supercomputers and emergence of computer net systems, willopen new avenues to rational drug design" (Portoghese, P. S. J. Med. Chem. 1989, 32, 1. Unknown pharmacological active compounds synthetized by plants can be found even without this eletronic devices, as tradicional medicine has pointed out in many contries, and give rise to a new drug. These compounds used as found in nature or after chemical modifications have produced successful experimental medicaments as FAA, "flavone acetic acid" with good results as inibitors of slow growing animal tumors currently in preclinical evaluation for human treatment. In this lecture some international contributions in the field of chemical modified compounds as antineoplasic drugs will be examined, particularly those done by Brazilian researches.

  13. 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.

  14. 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.

  15. 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.

  16. Characterization of brevetoxin metabolism in Karenia brevis bloom-exposed clams (Mercenaria sp.) by LC-MS/MS.

    Science.gov (United States)

    Abraham, Ann; Wang, Yuesong; El Said, Kathleen R; Plakas, Steven M

    2012-11-01

    Brevetoxin metabolites were identified and characterized in the hard clam (Mercenaria sp.) after natural exposure to Karenia brevis blooms by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Principal brevetoxins BTX-1 and BTX-2 produced by K. brevis were not detectable in clams. Metabolites of these brevetoxins found in clams included products of oxidation, reduction, hydrolysis and amino acid/fatty acid conjugation. Of highest abundance were cysteine and taurine conjugates. We also found glutathione, glycine-cysteine, and γ-glutamyl-cysteine conjugates. A series of fatty acid derivatives of cysteine-brevetoxin conjugates were also identified. PMID:22884629

  17. DOUBLE-BELLIED EXTENSOR DIGITORUM BREVIS MANUS

    Directory of Open Access Journals (Sweden)

    Lydia S. Quadros

    2014-10-01

    Full Text Available Most of the anatomical variations are noted during the cadaveric dissections. A rare variation of the Extensor digitorum brevis manus was observed on the dorsal aspect of the right hand of a 69-year-old male cadaver. This atavistic muscle had two bellies which originated from the dorsal aspect of the lower end of radius and the capsule of the wrist joint respectively. The two bellies fused to form a single tendon which inserted into the ulnar side of the dorsal digital expansion of the middle finger. Posterior interosseous nerve innervated the two bellies. This muscle may be involved in the wrist pain or may be misinterpreted as a ganglion or a nodule upon radiological examination. This muscle may be used for reconstructive purposes.

  18. 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. PMID:24598940

  19. 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.

  20. Chemical nature and sequence of alamethicin.

    Science.gov (United States)

    Martin, D R; Williams, R J

    1976-02-01

    An n.m.r. spectroscopy study of pure alamethicin shows it to be a linear polypeptide of 19 residues. The N-terminus is blocked by an acetyl group, and the eighteenth residue, glutamic acid, is linked by an amide bond on its side chain to phenylalaninol (Fig. 6). The new formula is confirmed by a comparison between pure chemical compounds and the products of partial hydrolysis. PMID:1275883

  1. Arginine specific aminopeptidase from Lactobacillus brevis

    Directory of Open Access Journals (Sweden)

    Arya Nandan

    2010-12-01

    Full Text Available The proteolytic system of lactic acid bacteria contribute to the development of flavor during the ripening of cheese through the generation of short peptides and free amino acids, which directly or indirectly act as flavor precursors. Newly isolated lactic acid bacteria (LAB as well as those procured from culture collection centers were screened for the production of various substrate specific aminopeptidases. Among all the strains screened, L. brevis (NRRL B-1836 was found to produce quantifiable amount of intracellular arginine specific aminopeptidase (EC 3.4.11.6. The productivity of arginine aminopeptidase in 5 L fermentor was 36 IU/L/h. The Luedeking and Piret model was tested for intracellular production of aminopeptidase and the data seemed to fit well, as the correlation coefficient was 0.9964 for MRS. The αAP and βAP was 0.4865 and 0.0046, respectively in MRS medium indicating that the yield was predominantly depended on growth. The culture produced lactic acid and also tolerated pH 2.0-3.0 and 0.3-0.5% bile salts, the most important probiotic features.

  2. Atlantic Forest. A natural reservoir of chemical elements

    International Nuclear Information System (INIS)

    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)

  3. Zinc in soybeans. Chemical nature and bioavilability

    International Nuclear Information System (INIS)

    Soybeans were grown hydroponically and intrinsically labeled with 65Zn through root absorption, stem injection and foliar application. Stem injection resulted in the greatest accumulation of 65Zn. Regardless of the labeling technique, approximately 40-45% of the seed 65Zn was associated with the subcellular organelles. The pattern of 65Zn incorporation into soybeans did not change appreciably as a result of the labelling technique. The major portion of the soluble 65Zn 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 65Zn from both casein and soy than rats adapted to a soy basal diet

  4. Zooplankton and Karenia brevis in the Gulf of Mexico

    Science.gov (United States)

    Lester, Kristen M.; Heil, Cynthia A.; Neely, Merry B.; Spence, Danylle N.; Murasko, Susan; Hopkins, Thomas L.; Sutton, Tracey T.; Burghart, Scott E.; Bohrer, Richard N.; Remsen, Andrew W.; Vargo, Gabriel A.; Walsh, John J.

    2008-01-01

    Blooms of the toxic dinoflagellate Karenia brevis are common in the Gulf of Mexico, yet no in situ studies of zooplankton and K. brevis have been conducted there. Zooplankton abundance and taxonomic composition at non-bloom and K. brevis bloom stations within the Ecology of Harmful Algal Blooms (ECOHAB) study area were compared. At non-bloom stations, the most abundant species of zooplankton were Parvocalanus crassirostris, Oithona colcarva, and Paracalanus quasimodo at the 5-m isobath and P. quasimodo, O. colcarva, and Oikopleura dioica at the 25-m isobath. There was considerable overlap in dominance of zooplankton species between the 5 and 25-m isobaths, with nine species contributing to 90% of abundance at both isobaths. At stations within K. brevis blooms however, Acartia tonsa, Centropages velificatus, Temora turbinata, Evadne tergestina, O. colcarva, O. dioica, and P. crassirostris were dominant. Variations in abundance between non-bloom and bloom assemblages were evident, including the reduction in abundance of three key species within K. brevis blooms.

  5. Chemical osmosis in natural clayey materials. Geologica Ultraiectina (196)

    NARCIS (Netherlands)

    Keijzer, T.J.S.

    2000-01-01

    Semipenneable properties of clayey natural materials can have a significant impact on a range of geological and geochemical processes on laboratory and field scale. The importance of chemical osmosis in semipenneable natural clays for transport of contaminants was first discussed in the Netherlands

  6. 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.

  7. The thermodynamic natural path in chemical reaction kinetics

    Directory of Open Access Journals (Sweden)

    Moishe garfinkle

    2000-01-01

    Full Text Available The Natural Path approach to chemical reaction kinetics was developed to bridge the considerable gap between the Mass Action mechanistic approach and the non-mechanistic irreversible thermodynamic approach. The Natural Path approach can correlate empirical kinetic data with a high degree precision, as least equal to that achievable by the Mass-Action rate equations, but without recourse mechanistic considerations. The reaction velocities arising from the particular rate equation chosen by kineticists to best represent the kinetic behavior of a chemical reaction are the natural outcome of the Natural Path approach. Moreover, by virtue of its thermodynamic roots, equilibrium thermodynamic functions can be extracted from reaction kinetic data with considerable accuracy. These results support the intrinsic validity of the Natural Path approach.

  8. Lactobacillus brevis Strains from Fermented Aloe vera Survive Gastroduodenal Environment and Suppress Common Food Borne Enteropathogens

    OpenAIRE

    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. Al...

  9. 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.

  10. 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 biotechnologica

  11. "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…

  12. Anatomical variation of the flexor digitorum brevis muscle revisited: a case report from South Indian population

    Directory of Open Access Journals (Sweden)

    Thangarajan R

    2010-12-01

    Full Text Available We observed a variation in the flexor digitorum brevis muscle of a 50-year-old female cadaver in our routine dissection. In the sole of right foot, we found that flexor digitorum brevis was giving only three tendons for middle three toes. The tendon of flexor digitorum brevis for the little toe was missing. The absent 4th tendon of the flexor digitorum brevis to little toe in the right foot was replaced by an isolated flexor muscle arising from the medial margin of the tendinous plate of the flexor digitorum brevis. The tendon of isolated flexor muscles inserted in to base of distal phalanx of the little toe. Variation of the flexor digitorum brevis may be important to plastic surgeons because of reconstruction of the heel pad by flexor digitorum brevis musculocutaneous flap transfer.

  13. Development of Natural Gas Chemical Engineering in China

    Institute of Scientific and Technical Information of China (English)

    Yuan Qingmin

    1996-01-01

    @@ The equivalent ratio of natural gas to oil has reached 0.73:1 worldwide by 1994. The Chinese output of natural gas and oil ranks the 22nd and 5th respectively in the world's oil and gas production. The quantity equivalent ratio of gas to oil in China is only 0.11:1, which can not meet the needs of future economic development. Since the beginning of the 1990s, the discovery and expansion of natural gas reserves in Sichuan, Shaanxi, Xinjiang and Hainan Provinces and offshore area have brought about a solid foundation for the rapid development of the country's natural gas industry. It is sure that a new era of the development of China's natural gas chemical engineering is coming.

  14. Chemical behaviour of transuranic elements in the natural environment

    International Nuclear Information System (INIS)

    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

  15. The nature of chemical innovation: new enzymes by evolution.

    Science.gov (United States)

    Arnold, Frances H

    2015-11-01

    I describe how we direct the evolution of non-natural enzyme activities, using chemical intuition and information on structure and mechanism to guide us to the most promising reaction/enzyme systems. With synthetic reagents to generate new reactive intermediates and just a few amino acid substitutions to tune the active site, a cytochrome P450 can catalyze a variety of carbene and nitrene transfer reactions. The cyclopropanation, N-H insertion, C-H amination, sulfimidation, and aziridination reactions now demonstrated are all well known in chemical catalysis but have no counterparts in nature. The new enzymes are fully genetically encoded, assemble and function inside of cells, and can be optimized for different substrates, activities, and selectivities. We are learning how to use nature's innovation mechanisms to marry some of the synthetic chemists' favorite transformations with the exquisite selectivity and tunability of enzymes.

  16. ANOTHER NITROGEN-FIXING MICROORGANISM IN SUGARCANE STALKS: Bacillus brevis?

    Directory of Open Access Journals (Sweden)

    Lorelí de los A. Mirabal

    2000-01-01

    Full Text Available Con el objetivo de identificar un microorganismo formador de colonias blancas en medio de cultivo LGI, prove- niente de savia apoplástica del tallo de la caña de azúcar, se realizaron diferentes experimentos en los que se utilizó la variedad ML-318. De la misma se extrajo savia apoplástica, de la cual se aisló el microorganismo de interés, al que se le realizaron pruebas morfológicas, culturales y bioquímicas, las que revelaron un 65 % de probabilidad de que el microorganismo de interés se corresponde con Bacillus brevis. Se detectó actividad nitrogenasa por la reducción de acetileno a etileno. Además, los resultados indican interacción entre Acetobacter diazotrophicus y el microorganismo formador de colonias blancas identificado como Bacillus brevis.

  17. EARLY ONTOGENETIC DEVELOPMENT OF Prochilodus brevis (STEINDACHNER, 1875 (CHARACIFORMES

    Directory of Open Access Journals (Sweden)

    Divana Eliva Oliveira Alves

    2016-03-01

    Full Text Available The study analyzed the stages of the embryonic development of the curimatã Prochilodus brevis, endemic fish of the northeast Brazilian, belonging the family Prochilodontidae (Characiformes. The embryos were obtained of the Estação de Piscicultura Estevão de Oliveira (DNOCS – Caicó, RN, Brazil. The collections were accomplished after the beginning of the spawning and fertilization of the oocytes, in intervals of one hour to the appearance of the larvae. The samples were fixed in 10% formaldehyde for morphological analysis and in Bouin's solution during a period of twelve hours, after they were processed through routine histological techniques. The eggs of P. brevis are spherical, transparent and non-adhesive. The main events reported during embryogenesis were: zygote, cleavage, morula, blastula, gastrula, organogenesis, hatching and larvae. These events are common to several species of teleost fish, the variation found are related to the chronology of each phase and the specific characteristics of oocytes and eggs. The characterization of the embryonic development of fish such as P. brevis, it is essential to suit the growing conditions to the biological needs of these animals. The data from this study agree with studies of species endemic to the northeastern region and expand the possibilities for their cultivation. Keywords: Embryogenesis; reproduction; aquaculture; developmental biology; curimatã.

  18. Characterization of Tamulamides A and B: Polyethers Isolated from the Marine Dinoflagellate Karenia brevis

    OpenAIRE

    Truxal, Laura T; Bourdelais, Andrea J.; Jacocks, Henry; Abraham, William M.; Baden, Daniel G.

    2010-01-01

    Florida red tides occur as the result of blooms of the marine dinoflagellate Karenia brevis. K. brevis is known to produce several families of fused polyether ladder compounds. The most notable compounds are the brevetoxins, potent neurotoxins that activate mammalian sodium channels. Additional fused polyether ladder compounds produced by K. brevis include brevenal, brevisin, and hemi-brevetoxin B, all with varying affinities for the same binding site on voltage sensitive sodium channels. The...

  19. 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).

  20. Influence of temperature on natural and chemically modified zeolites

    International Nuclear Information System (INIS)

    Zeolites from Nizny Hrabovec (Slovak Republic) were modified with solutions of NaOH. The changes of zeolites in the temperature range 20-1200 deg C were studied by thermal analysis (DTA, TG, ETA), X-ray analysis and REM analysis. Thermal analysis showed that the process of dehydration started between temperatures 20 and 600 deg C, over this temperature the dealumination and structural changes have taken place. X-ray analysis and REM analysis showed the structural changes of natural zeolites and gradual loss of cristallinity of the chemically modified zeolites. (author)

  1. 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.

  2. Redefining the vascular anatomy of the peroneus brevis muscle flap.

    Science.gov (United States)

    Ensat, Florian; Weitgasser, Laurenz; Hladik, Michaela; Larcher, Lorenz; Heinrich, Klemens; Skreiner, Anna; Russe, Elisabeth; Fuerntrath, Frank; Kamp, Jonas; Cotofana, Sebastian; Wechselberger, Gottfried

    2015-01-01

    The peroneus brevis flap can be used as either proximally or distally based flap for coverage of small to medium-sized defects in the lower leg. The purpose of this study was to clarify the vascular anatomy of the peroneus brevis muscle. An anatomical dissection was performed on 17 fixed adult cadaver lower legs. Altogether, 87 segmental branches (mean 5.1 ± 1.6 per leg) either from the fibular or anterior tibial artery to the muscle were identified. Sixty-two were branches from the fibular artery (mean 3.4 ± 1.1 per fibular artery), whereas 25 (mean 1.4 ± 0.9 per anterior tibial artery) originated from the anterior tibial artery. The distance between the most distal vascular branch and the malleolar tip averaged 4.3 ± 0.6 cm. An axial vascular bundle to the muscle could be identified in all cadavers; in one leg two axial supplying vessels were found. Their average length was 5.5 ± 2.4 cm and the average arterial diameter was 1.1 ± 0.5 mm, the average venous diameter was 1.54 ± 0.7 mm. The constant blood supply to the peroneus brevis muscle by segmental branches from the fibular and tibial artery make this muscle a viable option for proximally or distally pedicled flap transfer. The location of the most proximal and distal branches to the muscle and conclusively the pivot points for flap transfer could be determined. Furthermore, a constant proximal axial vascular pedicle to the muscle may enlarge the clinical applications. Perfusion studies should be conducted to confirm these findings. PMID:25046821

  3. Recurrent hypertrophic peroneal tubercle associated with peroneus brevis tendon tear.

    Science.gov (United States)

    Ochoa, Leah M; Banerjee, Rahul

    2007-01-01

    Stenosing peroneal tenosynovitis resulting from hypertrophy of the peroneal tubercle has been well described. Successful surgical treatment addresses the hypertrophied peroneal tubercle as well as any intrinsic tendon pathology. We report a case of recurrent foot pain caused by stenosing peroneal tenosynovitis in a 16-year-old woman. Four months after excision of a hypertrophic peroneal tubercle, the patient developed a recurrence of symptoms. Imaging studies, repeat operative exploration, and pathologic specimen demonstrated a recurrence of the peroneal tubercle hypertrophy associated with a longitudinal tear of the peroneus brevis tendon. Re-resection of the hypertrophied tubercle and peroneal tendon repair resulted in a resolution of symptoms. PMID:17761327

  4. Gramicidin S production by Bacillus brevis in simulated microgravity

    Science.gov (United States)

    Fang, A.; Pierson, D. L.; Mishra, S. K.; Koenig, D. W.; Demain, A. L.

    1997-01-01

    In a continuing study of microbial secondary metabolism in simulated microgravity, we have examined gramicidin S (GS) production by Bacillus brevis strain Nagano in NASA High Aspect Rotating Vessels (HARVs), which are designed to simulate some aspects of microgravity. Growth and GS production were found to occur under simulated microgravity. When performance under simulated microgravity was compared with that under normal gravity conditions in the bioreactors, GS production was found to be unaffected by simulated microgravity. The repressive effect of glycerol in flask fermentations was not observed in the HARV. Thus the negative effect of glycerol on specific GS formation is dependent on shear and/or vessel geometry, not gravity.

  5. 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 exten

  6. 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 ...

  7. Chemical evolution and nature of Damped Lyman-Alpha systems

    CERN Document Server

    Calura, F; Vladilo, G

    2003-01-01

    We study the nature of Damped Lyman -Alpha systems (DLAs) by means of a comparison between observed abundances and models of chemical evolution of galaxies of different morphological type. In particular, we compare for the first time the abundance ratios as functions of metallicity and redshift with dust-corrected data. We have developed detailed models following the evolution of several chemical elements (H, D, He, C, N, O, Ne, Mg, Si, S, Fe, Ni and Zn) for elliptical, spiral and irregular galaxies. Each of the models is calibrated to reproduce the main features of a massive elliptical, the Milky Way and the LMC, respectively. In addition, we run some models also for dwarf irregular starburst galaxies. All the models share the same uptodate nucleosynthesis prescriptions but differ in their star formation histories. The role of SNe of different type (II, Ia) is studied in each galaxy model together with detailed and up to date nucleosynthesis prescriptions. Our main conclusions are: 1) when dust depletion is ...

  8. `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.

  9. Extensor digitorum brevis and extensor hallusis brevis transplantation for treatment of long-standing facial pa-ralysis

    Institute of Scientific and Technical Information of China (English)

    HUANG Wei-qing; FANG Bai-rong; FANG Xue-quan; WANG Chang-jun

    2009-01-01

    Objective: To evaluate the efficacy of free transplan-tation of denervated muscles and vessels in the treatment of long-standing facial paralysis.Methods: A total of 26 patients with facial paralysis (10 males and 16 females, aged 16-65 years, mean: 47 years) were enrolled in this study to receive transplantation of denervated extensor digitorum brevis (EDB) and extensor hallusis brevis (EHB). The muscle tendon was slung to the ala nasi, the middle point of the nasolabial sulcus, the angu-lus otis and the chin to correct the nasal and oral deformity. The muscle belly was buried around the nerves that inner-vated the masseter muscle. Microsurgery was applied to anastomosing the tarsus lateral vessels to the superficial temporalis vessels.Results: After operation, all the patients immediately obtained satisfied static appearance. The movement of the paralyzed comer of the mouth could be obtained one month later and the smile of the paralyzed side could be restored after 3 months of training. And 88% patients achieved per-fect results, 8% obtained satisfactory results, and 4% got improvement 6 months after operation according to Stennert's paresis scoring system.Conclusions: Free transplantation of denervated muscles and vessels for the treatment of long-standing fa-cial paralysis, which seldom causes atrophy or liquefaction of the transferred muscles, can maintain muscle viability and induce reliable nerve regeneration. Therefore, it is a safe and efficient treatment method for the patients suffer-ing from facial paralysis.

  10. Conversion chimique du gaz naturel Chemical Conversion of Natural Gas

    Directory of Open Access Journals (Sweden)

    Chaumette P.

    2006-11-01

    Full Text Available Dans cet article sont passés en revue les travaux de recherche et développement et les procédés existants dans le domaine de la conversion chimique du gaz naturel. Les deux voies possibles, conversion directe du méthane et conversion indirecte, via le gaz de synthèse, sont présentées. Tant la préparation d'hydrocarbures utilisables comme carburants, que celle des composés de bases pour la pétrochimie ou la chimie sont évoquées. L'accent est mis sur l'étape clé du développement de chaque procédé qui, selon le produit visé, consiste en la mise au point d'un nouveau système catalytique, en un changement de la technologie du réacteur, ou en la mise au point d'une section fractionnement moins complexe. This article reviews the research and development work and the existing processes in the area of chemical conversion of natural gas. The two possible methods, direct conversion of methane and indirect conversion via synthesis gas, are discussed. The preparation of hydrocarbons that can be used as fuels and the production of building blocks for the petrochemical and chemical industries are both dealt with. The accent is placed on the key step in developing each process. Depending on the target product, this key step consists in working out a new catalytic system, changing reactor technology or engineering a less complex fractionation section.

  11. Extensor digitorum brevis manus: Its clinical significance and morphology

    Directory of Open Access Journals (Sweden)

    Bolla SR

    2008-12-01

    Full Text Available Anomalous muscles are often a matter of concern to clinicians as they mislead the diagnosis. Knowledge of such variant muscles is important clinically to avoid misdiagnosis. In this report we present an anomalous muscle on the dorsum of hand, extensor digitorum brevis manus an uncommon variation present as a swelling on the dorsum. It is originated from the dorsal wrist capsule within the compartment deep to the extensor retinaculum for the extensor digitorum and inserted into the extensor hood of the index finger, this variant muscle often cause dorsal wrist pain and often confused as ganglion, soft tissue tumor, synovial cyst or tenovaginitis. The presence of such variant muscles on dorsum of hand, their clinical significance and literature has been reviewed.

  12. Biosynthesis of isotopically labeled gramicidins and tyrocidins by Bacillus brevis

    Energy Technology Data Exchange (ETDEWEB)

    Vogt, T.C. Bas; Schinzel, Susan [Max-Planck-Institut fuer Biochemie (Germany); Bechinger, Burkhard [Universite Strasbourg, Faculte de chimie, Institut Le Bel (France)], E-mail: bechinger@chimie.u-strasbg.fr

    2003-05-15

    The three-dimensional structure of bilayer-associated gramicidin A is available from a structural data base. This and related peptides are, therefore, ideal model compounds to use during the implementation and development of new NMR techniques for the structural investigations of membrane proteins. As these methods rely on the isotopic labelling of single, selected or all sites, we have, investigated and optimised biochemical protocols using different strains of the Gram-positive bacterium Bacillus brevis. With newly developed schemes for isotopic labelling large amounts of gramicidin and tyrocidin enriched with stable isotopes such as {sup 15}N or {sup 15}N/{sup 13}C have been obtained at low cost. A variety of analytical and spectroscopic techniques, including HPLC, mass spectrometry and NMR spectroscopy are used to characterise the resulting products.

  13. Unusual location of a posttraumatic ganglion and rupture of the peroneus brevis tendon: a case report.

    Science.gov (United States)

    Waldecker, Ute

    2005-01-01

    The typical location of a peroneus brevis tendon tear has been described at the posterior margin of the fibula due to an entrapment mechanism or repetitive anterior subluxation of the tendon. A case of a posttraumatic intratendinous ganglion of the peroneus brevis tendon in the distal third of the peroneus brevis is reported. The ganglion developed from a longitudinal tear in the tendon substance after an inversion ankle sprain. This case is reported because of the unusual location. The clinical course and surgical treatment is also discussed. PMID:15768368

  14. Lipid Class, Carotenoid, and Toxin Dynamics of Karenia Brevis (Dinophyceae) During Diel Vertical Migration

    Science.gov (United States)

    Karenia brevis’ (Hansen and Moestrup) internal lipid, carotenoid, and toxin concentrations are influenced by its ability to use ambient light and nutrients for growth and reproduction. This project investigated changes of K. brevis toxicity, lipid class and carotenoid concentrat...

  15. Controversies in Surgical Management of Recalcitrant Enthesopathy of the Extensor Carpi Radialis Brevis.

    Science.gov (United States)

    Gregory, Bonnie P; Wysocki, Robert W; Cohen, Mark S

    2016-08-01

    Enthesopathy of the extensor carpi radialis brevis, often referred to as "tennis elbow," is common and responds to nonsurgical treatment in 80% to 90% of patients within 1 year. For those who proceed with surgery, much remains unclear regarding the ideal treatment. This paper discusses controversies in surgical management of extensor carpi radialis brevis enthesopathy including clinical outcomes of open versus arthroscopic techniques, the relevance of concomitant pathology addressed arthroscopically, and avenues for assessing comparative cost data. PMID:27491631

  16. Alternative Reproductive Tactics in the Shell-Brooding Lake Tanganyika Cichlid Neolamprologus brevis

    OpenAIRE

    Kazutaka Ota; Mitsuto Aibara; Masaya Morita; Satoshi Awata; Michio Hori; Masanori Kohda

    2012-01-01

    Alternative reproductive tactics (ARTs) are found in several Lake Tanganyika shell-brooding cichlids. Field studies were conducted in the Wonzye population to examine reproductive ecology and ARTs in the Lake Tanganyika shell-brooding cichlid Neolamprologus brevis. We discovered that this fish occurred in both rocky- and sandy-bottom habitats, but in rocky habitats, brood-caring females exclusively occurred in shell-patches that another cichlid species created. All N. brevis of both sexes in ...

  17. Summarizing Statement of Insecticidal Effect on Vegetables and Application Techniques of Pesticide Empedobacter Brevis%短稳杆菌对蔬菜应用技术综述

    Institute of Scientific and Technical Information of China (English)

    吴铭忻; 周晶; 王亚超; 殷逸能; 万鑫

    2011-01-01

    短稳杆菌农药是我国自主创制的一种生物杀虫剂,对小菜蛾、斜纹夜蛾及其他鳞翅目害虫有很好的杀虫效果,对蔬菜本身及害虫天敌无不良影响,对人畜禽安全性好。100亿孢子/mL短稳杆菌悬浮剂用于蔬菜大田害虫防治,应当准确掌握用药对象、用药时期及用药方法。%Pesticide Empedobacter brevis is our own creation of a biological insecticide.It has very good insecticidal effect on diamondback moth,Prodenia litura and other Lepidoptera pests.It has no adversely affection on vegetables and natural enemies of pests,and it's safe for people、livestock and poultry.10 000 000 000 spores / mL Empedobacter brevis Suspending agent is used on Prevention of vegetable pests.We should have accurately master of Control object,time and method of pesticide Empedobacter brevis.

  18. 75 FR 38092 - The Dow Chemical Company; Application for Blanket Authorization To Export Liquefied Natural Gas

    Science.gov (United States)

    2010-07-01

    ... The Dow Chemical Company (Dow), requesting blanket authorization to export liquefied natural gas (LNG... with its principal place of business in Midland, Michigan. Dow is an international chemical and...\\ The Dow Chemical Company, DOE/FE Order No. 2754 issued February 25, 2010. Current Application In...

  19. Capturing Biological Activity in Natural Product Fragments by Chemical Synthesis.

    Science.gov (United States)

    Crane, Erika A; Gademann, Karl

    2016-03-14

    Natural products have had an immense influence on science and have directly led to the introduction of many drugs. Organic chemistry, and its unique ability to tailor natural products through synthesis, provides an extraordinary approach to unlock the full potential of natural products. In this Review, an approach based on natural product derived fragments is presented that can successfully address some of the current challenges in drug discovery. These fragments often display significantly reduced molecular weights, reduced structural complexity, a reduced number of synthetic steps, while retaining or even improving key biological parameters such as potency or selectivity. Examples from various stages of the drug development process up to the clinic are presented. In addition, this process can be leveraged by recent developments such as genome mining, antibody-drug conjugates, and computational approaches. All these concepts have the potential to identify the next generation of drug candidates inspired by natural products.

  20. Compositional changes in neurotoxins and their oxidative derivatives from the dinoflagellate, Karenia brevis, in seawater and marine aerosol

    OpenAIRE

    Pierce, Richard H.; Henry, Michael S.; Blum, Patricia C.; Osborn, Shannon E.; Cheng, Yung-Sung; Zhou, Yue; Irvin, Clinton M.; Bourdelais, Andrea J.; Naar, Jerome; Baden, Daniel G.

    2010-01-01

    The harmful alga, Karenia brevis, produces a suite of polyether neurotoxins, brevetoxins or PbTx, that cause marine animal mortality and neurotoxic shellfish poisoning (NSP). A characteristic of K. brevis blooms is associated airborne toxins that result in severe respiratory problems. This study was undertaken to determine the composition of aerosolized brevetoxins and oxidative derivatives to which beachgoers are exposed during a K. brevis bloom. The suite of brevetoxins and derivatives in s...

  1. Use of Natural Products as Chemical Library for Drug Discovery and Network Pharmacology

    OpenAIRE

    Jiangyong Gu; Yuanshen Gui; Lirong Chen; Gu Yuan; Hui-Zhe Lu; Xiaojie Xu

    2013-01-01

    BACKGROUND: Natural products have been an important source of lead compounds for drug discovery. How to find and evaluate bioactive natural products is critical to the achievement of drug/lead discovery from natural products. METHODOLOGY: We collected 19,7201 natural products structures, reported biological activities and virtual screening results. Principal component analysis was employed to explore the chemical space, and we found that there was a large portion of overlap between natural pr...

  2. Compound Activity Mapping: Integrating Chemical and Biological Profiling for the Functional Annotation of Natural Product Libraries

    OpenAIRE

    Kurita, Kenji Long

    2015-01-01

    Natural products research has had a significant impact on human-health and our understanding of the natural world as a pillar of pharmacognosy, organic chemistry, ecology, and chemical biology. But while this science has yielded countless discoveries such as penicillin, taxol, and artimesinin and will continue to improve quality of life around the world, the idea that natural products is a panacea of chemical diversity has been challenged by problems including the endless rediscovery of known...

  3. Secondary metabolites from natural sources: chemical and pharmacological characterization

    OpenAIRE

    Festa, Carmen

    2010-01-01

    Natural products have long been a source of bioactive metabolites utilized for the treatment of human disease. In spite the impressive progress of new competing methodologies, as for example, combinatorial chemistry and high-throughput screening or genetic engineering, natural products remain a valuable source of bioactive compounds with therapeutic potential. In recent years, the marine environment has been seen as a vast resource for the discovery of structurally unique bioactive secon...

  4. On the Nature of "Context" in Chemical Education

    Science.gov (United States)

    Gilbert, John K.

    2006-01-01

    Some of the most pressing problems currently facing chemical education throughout the world are rehearsed. It is suggested that if the notion of "context" is to be used as the basis for an address to these problems, it must enable a number of challenges to be met. Four generic models of "context" are identified that are currently used or that may…

  5. Natural product diversity and its role in chemical biology and drug discovery

    OpenAIRE

    Hong, Jiyong

    2011-01-01

    Through the natural selection process, natural products possess a unique and vast chemical diversity and have been evolved for optimal interactions with biological macromolecules. Owing to their diversity, target affinity, and specificity, natural products have demonstrated enormous potential as modulators of biomolecular function, been an essential source for drug discovery, and provided design principles for combinatorial library development.

  6. Use of natural products as chemical library for drug discovery and network pharmacology.

    Directory of Open Access Journals (Sweden)

    Jiangyong Gu

    Full Text Available BACKGROUND: Natural products have been an important source of lead compounds for drug discovery. How to find and evaluate bioactive natural products is critical to the achievement of drug/lead discovery from natural products. METHODOLOGY: We collected 19,7201 natural products structures, reported biological activities and virtual screening results. Principal component analysis was employed to explore the chemical space, and we found that there was a large portion of overlap between natural products and FDA-approved drugs in the chemical space, which indicated that natural products had large quantity of potential lead compounds. We also explored the network properties of natural product-target networks and found that polypharmacology was greatly enriched to those compounds with large degree and high betweenness centrality. In order to make up for a lack of experimental data, high throughput virtual screening was employed. All natural products were docked to 332 target proteins of FDA-approved drugs. The most potential natural products for drug discovery and their indications were predicted based on a docking score-weighted prediction model. CONCLUSIONS: Analysis of molecular descriptors, distribution in chemical space and biological activities of natural products was conducted in this article. Natural products have vast chemical diversity, good drug-like properties and can interact with multiple cellular target proteins.

  7. Biosynthesis and Chemical Synthesis of Presilphiperfolanol Natural Products**

    OpenAIRE

    Hong, Allen Y.; Stoltz, Brian M.

    2014-01-01

    Presilphiperfolanols constitute a family of biosynthetically important sesquiterpenes that can rearrange to diverse sesquiterpenoid skeletons. While the origin of these natural products can be traced to simple linear terpene precursors, the details of the enzymatic cyclization mechanism that form the stereochemically dense tricyclic skeleton have required extensive biochemical, computational, and synthetic investigation. Parallel efforts to prepare the unique and intriguing structures of thes...

  8. 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 rea

  9. Chemical proteomics approaches for identifying the cellular targets of natural products.

    Science.gov (United States)

    Wright, M H; Sieber, S A

    2016-05-01

    Covering: 2010 up to 2016Deconvoluting the mode of action of natural products and drugs remains one of the biggest challenges in chemistry and biology today. Chemical proteomics is a growing area of chemical biology that seeks to design small molecule probes to understand protein function. In the context of natural products, chemical proteomics can be used to identify the protein binding partners or targets of small molecules in live cells. Here, we highlight recent examples of chemical probes based on natural products and their application for target identification. The review focuses on probes that can be covalently linked to their target proteins (either via intrinsic chemical reactivity or via the introduction of photocrosslinkers), and can be applied "in situ" - in living systems rather than cell lysates. We also focus here on strategies that employ a click reaction, the copper-catalysed azide-alkyne cycloaddition reaction (CuAAC), to allow minimal functionalisation of natural product scaffolds with an alkyne or azide tag. We also discuss 'competitive mode' approaches that screen for natural products that compete with a well-characterised chemical probe for binding to a particular set of protein targets. Fuelled by advances in mass spectrometry instrumentation and bioinformatics, many modern strategies are now embracing quantitative proteomics to help define the true interacting partners of probes, and we highlight the opportunities this rapidly evolving technology provides in chemical proteomics. Finally, some of the limitations and challenges of chemical proteomics approaches are discussed.

  10. Polycyclic Xanthone Natural Products: Structure, Biological Activity and Chemical Synthesis

    OpenAIRE

    Winter, Dana K.; Sloman, David L.; Porco, John A.

    2013-01-01

    Polycyclic xanthone natural products are a family of polyketides which are characterized by highly oxygenated, angular hexacyclic frameworks. In the last decade, this novel class of molecules has attracted noticeable attention from the synthetic and biological communities due to emerging reports of their potential use as antitumour agents. The aim of this article is to highlight the most recent developments of this subset of the xanthone family by detailing the innate challenges of the constr...

  11. A New `Idea of Nature' for Chemical Education

    Science.gov (United States)

    Earley, Joseph E.

    2013-07-01

    "The idea of nature" (general model of how things work) that is accepted in a society strongly influences that group's social and technological progress. Currently, science education concentrates on analysis of stable pre-existing items to minimum constituents. This emphasis is consistent with an outlook that has been widely accepted since the late Renaissance—that characteristics of individuals depend exclusively on the properties of their microscopic components. Much of 19th and 20th century science seems compatible with that now-traditional outlook. But major parts of contemporary science (and fundamental technological problems) deal with open- system dynamic coherences that display novel and important characteristics. These important entities are not adequately treated by the presently-dominant idea of nature. In contrast, the notion of how the world works that contemporary science and current technological practice generate emphasizes synthesis and self- organization of far-from-equilibrium "dissipative structures." Arguably, eventual success in meeting the severe technological and social challenges occasioned by increasing world population will require general diffusion and appreciation of that newer overall outlook. Chemistry educators have been important in developing and disseminating the earlier worldview—they can and should provide leadership for widespread adoption of the alternative idea of nature.

  12. 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.

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

    Science.gov (United States)

    Sharma, Deepak; Patel, Ankur; Soni, Priyanka; Sharma, Pradeep; Gupta, Basudev

    2016-01-01

    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. PMID:27648334

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

    Science.gov (United States)

    Patel, Ankur; Soni, Priyanka; Sharma, Pradeep; Gupta, Basudev

    2016-01-01

    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. PMID:27648334

  15. 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.

  16. Effect of Lactobacillus brevis ATCC 8287 as a feeding supplement on the performance and immune function of piglets

    Science.gov (United States)

    Lactobacillus brevis ATCC 8287, a surface (S-layer) strain, possesses a variety of functional properties that make it both a potential probiotic and a good vaccine vector candidate. With this in mind, our aim was to study the survival of L. brevis in the porcine gut and investigate the effect of th...

  17. Draft Genome Sequence of Brevibacillus brevis DZQ7, a Plant Growth-Promoting Rhizobacterium with Broad-Spectrum Antimicrobial Activity

    OpenAIRE

    Hou, Qihui; Wang, Chengqiang; Hou, Xiaoyang; Xia, Zhilin; Ye, Jiangping; Liu, Kai; Liu, Hu; Wang, Jun; Guo, Haimeng; Yu, Xiaoning; Yang, Yanan; Du, Binghai; Ding, Yanqin

    2015-01-01

    Brevibacillus brevis DZQ7 is a plant growth-promoting rhizobacterium (PGPR) isolated from tobacco rhizosphere. Here, we report the draft genome sequence of B. brevis DZQ7. Several functional genes related to antimicrobial activity were identified in the genome.

  18. Draft Genome Sequence of Brevibacillus brevis DZQ7, a Plant Growth-Promoting Rhizobacterium with Broad-Spectrum Antimicrobial Activity.

    Science.gov (United States)

    Hou, Qihui; Wang, Chengqiang; Hou, Xiaoyang; Xia, Zhilin; Ye, Jiangping; Liu, Kai; Liu, Hu; Wang, Jun; Guo, Haimeng; Yu, Xiaoning; Yang, Yanan; Du, Binghai; Ding, Yanqin

    2015-01-01

    Brevibacillus brevis DZQ7 is a plant growth-promoting rhizobacterium (PGPR) isolated from tobacco rhizosphere. Here, we report the draft genome sequence of B. brevis DZQ7. Several functional genes related to antimicrobial activity were identified in the genome. PMID:26294619

  19. Chemical and pharmacological significance of natural guanidines from marine invertebrates.

    Science.gov (United States)

    Ebada, S S; Proksch, P

    2011-03-01

    Natural Guanidines from marine invertebrates represent a group of bioactive secondary metabolites that revealed prominent pharmacological activities such as antimicrobial, antiproliferative, analgesic, and anti-coagulant properties. Acyclovir (Zovirax(®)), the first guanidine-derived pharmaceutical for the treatment of herpes infections since late 1970s, was synthesized based on a marine arabinosyl nucleoside, spongosine. Recently, ziconotide (Prialt(®)), a synthetic form of the marine-derived peptide (ω-conotoxin MVIIA) comprising a guanidine moiety, has been approved for the treatment of chronic pain. This review surveys over 130 compounds of guanidine-containing secondary metabolites from marine invertebrates with emphasis on their pharmacological significance and structure-activity relationships. PMID:21534931

  20. Organics. [Nature and analysis of chemical species in water systems

    Energy Technology Data Exchange (ETDEWEB)

    DeWalle, F.B. (Univ. of Washington, Seattle); Lo, C.; Sung, J.; Kalman, D.; Chian, E.S.K.; Giabbai, M.; Ghosal, M.

    1982-01-01

    This literature review presents an overview of nonspecific methods, followed by group and compound specific methods used in the analysis of detergents, aliphatic and aromatic hydrocarbons, pesticides and herbicides, and in process and industrially related compounds. Many studies are focused on polychlorinated biphenyls (PCB) because of their persistant character in nature even after a substantial decrease in usage. Their presence in sediments is correlated with organic matter and clay owing to their adsorption to these materials. They are also observed in effluents from combustion processes and in sludges from treatment units. Bacteria have been identified that degrade PCBs and give higher rates than the 1-year turnover rate observed in coastal waters. Industrially derived organics have been detected in surface and ground water, drinking water and waste water. Coal conversion processes can lead to releases of toxic nitrogen-containing compounds such as pyridines and sulfur heterocyclics. Included are 8 tables and 242 references. (JMT)

  1. Isolated bilateral absence of abductor pollicis brevis and opponens pollicis muscles: A case report

    Directory of Open Access Journals (Sweden)

    Cihan Sahin

    2016-04-01

    Full Text Available We report a rare case of a 21-year-old man with a bilateral absence of abductor pollicis brevis and opponens pollicis muscles, which has not been previously reported. He presented with weakness in both of his hands. On physical examination there was atrophy on the thenar eminences of both of his hands and there was an absence of gross functional impairment in his hand functions. On magnetic resonance imaging, abductor pollicis brevis and opponens pollicis muscles were bilaterally absent. [Hand Microsurg 2016; 5(1.000: 29-31

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

    OpenAIRE

    Babu Bajantri; Ravindra Bharathi; Sanjai Ramkumar; Latheesh Latheef; Smitha Dhane; S Raja Sabapathy

    2013-01-01

    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...

  3. The diet of Enoplus brevis (Nematoda) in a supralittoral salt marsh of the North Sea

    Science.gov (United States)

    Hellwig-Armonies, Monika; Armonies, Werner; Lorenzen, Sievert

    1991-09-01

    The gut content of nearly 2000 specimens of Enoplus brevis was quantitatively analysed. E. brevis is an opportunistic omnivore. Main food categories found were cyanobacteria, diatoms, oligochaetes, nematodes, and rotifers. With a few exceptions, the diet of females and males was identical. Predominantly, juveniles fed on cyanobacteria and adults on animal prey. Experiments revealed that living oligochaetes are attacked and preyed upon. The quantities of the food categories eaten by Enoplus varied according to their ambient abundance, both temporarily and spatially on a small scale. At least the nematode prey was strongly selected: some species were significantly preferred and others avoided.

  4. Chemically sulfated natural galactomannans with specific antiviral and anticoagulant activities.

    Science.gov (United States)

    Muschin, Tegshi; Budragchaa, Davaanyam; Kanamoto, Taisei; Nakashima, Hideki; Ichiyama, Koji; Yamamoto, Naoki; Shuqin, Han; Yoshida, Takashi

    2016-08-01

    Naturally occurring galactomannans were sulfated to give sulfated galactomannans with degrees of substitution of 0.7-1.4 per sugar unit and molecular weights of M¯n=0.6×10(4)-2.4×10(4). Sulfated galactomannans were found to have specific biological activities in vitro such as anticoagulant, anti-HIV and anti-Dengue virus activities. The biological activities were compared with those of standard dextran and curdlan sulfates, which are polysaccharides with potent antiviral activity and low cytotoxicity. It was found that sulfated galactomannans had moderate to high anticoagulant activity, 13.4-36.6unit/mg, compared to that of dextran and curdlan sulfates, 22.7 and 10.0unit/mg, and high anti-HIV and anti-Dengue virus activities, 0.04-0.8μg/mL and 0.2-1.1μg/mL, compared to those curdlan sulfates, 0.1μg/mL, respectively. The cytotoxicity on MT-4 and LCC-MK2 cells was low. Surface plasmon resonance (SPR) of sulfated galactomannans revealed strong interaction with poly-l-lysine as a model compound of virus proteins, and suggested that the specific biological activities might originate in the electrostatic interaction of negatively charged sulfate groups of sulfated galactomannans and positively charged amino groups of surface proteins of viruses. These results suggest that sulfated galactomannans effectively prevented the infection of cells by viruses and the degree of substitution and molecular weights played important roles in the biological activities. PMID:27154517

  5. 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...

  6. Alternative Reproductive Tactics in the Shell-Brooding Lake Tanganyika Cichlid Neolamprologus brevis

    Directory of Open Access Journals (Sweden)

    Kazutaka Ota

    2012-01-01

    Full Text Available Alternative reproductive tactics (ARTs are found in several Lake Tanganyika shell-brooding cichlids. Field studies were conducted in the Wonzye population to examine reproductive ecology and ARTs in the Lake Tanganyika shell-brooding cichlid Neolamprologus brevis. We discovered that this fish occurred in both rocky- and sandy-bottom habitats, but in rocky habitats, brood-caring females exclusively occurred in shell-patches that another cichlid species created. All N. brevis of both sexes in the patches were sexually mature, whereas immature males and females with unripe eggs were found frequently in sandy-bottom habitats. Males in sandy-bottom habitats were smaller, but fed more frequently and were in better somatic condition than males in the patches. Similar tendency was found in females. This indicates that N. brevis uses different habitats depending on the stage of its life history, with migration from sandy-bottom habitats to the shell-patches for reproduction. Males in the patches exhibited different behavior patterns: floating above the patches and lying in the patches. The former was larger, more aggressive, and invested less in gonads (relative to body size than the latter. These results accord with those of other shell-brooding Lake Tanganyika cichlids with ARTs, and they therefore suggest the presence of ARTs in N. brevis.

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

    Energy Technology Data Exchange (ETDEWEB)

    McPherson, G.; Pintauro, P.; O`Connor, S. [and others

    1996-05-02

    This project focuses on the chemical aspects of remediation, with the underlying theme that chemical remediation does occur naturally. Included are studies on the fate of heavy metal and organic contaminants discharged into aquatic environments; accurate assay metal contaminants partitioned into soils, water and tissue; development of novel polymeric membranes and microporous solids for the entrapment of heavy metals; and the development of hybrid chemo-enzymatic oxidative schemes for aromatics decontamination. 49 refs.

  9. Treatment of Actual Chemical Wastewater by a Heterogeneous Fenton Process Using Natural Pyrite

    OpenAIRE

    Liang Sun; Yan Li; Aimin Li

    2015-01-01

    Wastewater from chemical plants has remarkable antibiotic effects on the microorganisms in traditional biological treatment processes. An enhanced Fenton system catalyzed by natural pyrite was developed to degrade this kind of wastewater. Approximately 30% chemical oxygen demand (COD) was removed within 120 min when 50 mmol/L H2O2 and 10 g/L natural pyrite were used at initial pH from 1.8 to 7. A BOD5/COD enhancement efficiency of 210% and an acute biotoxicity removal efficiency of 84% were a...

  10. Utilisation of coal and natural gas for the production of synfuels and chemicals in South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Scott, R.H.; Marriott, J.N.; Stones, J.D.A. (Department of Mineral and Energy Affairs, Lynwood Ridge (South Africa). Energy Branch)

    1992-01-01

    Initially, the paper discusses coal, natural gas, condensate and crude-oil resources in South Africa. Aspects of the utilisation of coal for synfuels and chemicals manufacture discussed include: background; strategic and economic considerations; and technological developments. Aspects of the utilisation of natural gas and condensate for synfuels manufacture discussed include: continuation of synfuels programme in the eighties; financing principles and economic viability. Other aspects of synfuels manufacture in general covered are: macro-economics of the synfuels programme; chemicals production from coal; environmental considerations and future prospects. 7 refs., 4 figs.

  11. BIO-DIAGNOSTICS OF STABILITY OF BROWN CALCAREOUS SOIL OF UTRISH NATURAL RESERVE TO CHEMICAL POLLUTION

    OpenAIRE

    Kolesnikov S. I.; Vernigorova N. A.; Kuzina A. A.; Laptinova A. S.; Kazeev K. S.

    2015-01-01

    In this article, we have presented a number of modeling experiments to investigate the chemical pollution of brown calcareous soil. It assesses the stability of brown calcareous soil of a nature reserve called Utrish to contamination with heavy metals in biological parameters. Pollution of brown calcareous soil with Cr, Cu, Ni, Pb and oil causes a significant reduction in biological parameters. The degree of reduction depends on the nature of the contaminant and its concentration in the soil....

  12. 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…

  13. Leachability of cobalt and cesium from natural and chemically treated zeolites

    International Nuclear Information System (INIS)

    The determination of leachability of radioisotopes of cesium and cobalt from preloaded zeolites in distilled water, base solution and acid solution has been studied. For the experiment, we used natural and chemically treated zeolites. The zeolites before leaching were calcined at different temperatures. (author). 8 refs., 5 figs., 2 tabs

  14. Production of gamma-aminobutyric acid by Lactobacillus brevis NCL912 using fed-batch fermentation

    Directory of Open Access Journals (Sweden)

    Huang Guidong

    2010-11-01

    Full Text Available Abstract Background Gamma-aminobutyric acid is a major inhibitory neurotransmitter in mammalian brains, and has several well-known physiological functions. Lactic acid bacteria possess special physiological activities and are generally regarded as safe. Therefore, using lactic acid bacteria as cell factories for gamma-aminobutyric acid production is a fascinating project and opens up a vast range of prospects for making use of GABA and LAB. We previously screened a high GABA-producer Lactobacillus brevis NCL912 and optimized its fermentation medium composition. The results indicated that the strain showed potential in large-scale fermentation for the production of gamma-aminobutyric acid. To increase the yielding of GABA, further study on the fermentation process is needed before the industrial application in the future. In this article we investigated the impacts of pyridoxal-5'-phosphate, pH, temperature and initial glutamate concentration on gamma-aminobutyric acid production by Lactobacillus brevis NCL912 in flask cultures. According to the data obtained in the above, a simple and effective fed-batch fermentation method was developed to highly efficiently convert glutamate to gamma-aminobutyric acid. Results Pyridoxal-5'-phosphate did not affect the cell growth and gamma-aminobutyric acid production of Lb. brevis NCL912. Temperature, pH and initial glutamate concentration had significant effects on the cell growth and gamma-aminobutyric acid production of Lb. brevis NCL912. The optimal temperature, pH and initial glutamate concentration were 30-35°C, 5.0 and 250-500 mM. In the following fed-batch fermentations, temperature, pH and initial glutamate concentration were fixed as 32°C, 5.0 and 400 mM. 280.70 g (1.5 mol and 224.56 g (1.2 mol glutamate were supplemented into the bioreactor at 12 h and 24 h, respectively. Under the selected fermentation conditions, gamma-aminobutyric acid was rapidly produced at the first 36 h and almost not

  15. 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

    2014-07-01

    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. PMID:24939725

  16. Advances in identification and validation of protein targets of natural products without chemical modification.

    Science.gov (United States)

    Chang, J; Kim, Y; Kwon, H J

    2016-05-01

    Covering: up to February 2016Identification of the target proteins of natural products is pivotal to understanding the mechanisms of action to develop natural products for use as molecular probes and potential therapeutic drugs. Affinity chromatography of immobilized natural products has been conventionally used to identify target proteins, and has yielded good results. However, this method has limitations, in that labeling or tagging for immobilization and affinity purification often result in reduced or altered activity of the natural product. New strategies have recently been developed and applied to identify the target proteins of natural products and synthetic small molecules without chemical modification of the natural product. These direct and indirect methods for target identification of label-free natural products include drug affinity responsive target stability (DARTS), stability of proteins from rates of oxidation (SPROX), cellular thermal shift assay (CETSA), thermal proteome profiling (TPP), and bioinformatics-based analysis of connectivity. This review focuses on and reports case studies of the latest advances in target protein identification methods for label-free natural products. The integration of newly developed technologies will provide new insights and highlight the value of natural products for use as biological probes and new drug candidates. PMID:26964663

  17. 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.

  18. Mining Natural-Products Screening Data for Target-Class Chemical Motifs.

    Science.gov (United States)

    Coma, Isabel; Bandyopadhyay, Deepak; Diez, Emilio; Ruiz, Emilio Alvarez; de los Frailes, Maria Teresa; Colmenarejo, Gonzalo

    2014-06-01

    In this article, we describe two complementary data-mining approaches used to characterize the GlaxoSmithKline (GSK) natural-products set (NPS) based on information from the high-throughput screening (HTS) databases. Both methods rely on the aggregation and analysis of a large set of single-shot screening data for a number of biological assays, with the goal to reveal natural-product chemical motifs. One of them is an established method based on the data-driven clustering of compounds using a wide range of descriptors,(1)whereas the other method partitions and hierarchically clusters the data to identify chemical cores.(2,3)Both methods successfully find structural scaffolds that significantly hit different groups of discrete drug targets, compared with their relative frequency of demonstrating inhibitory activity in a large number of screens. We describe how these methods can be applied to unveil hidden information in large single-shot HTS data sets. Applied prospectively, this type of information could contribute to the design of new chemical templates for drug-target classes and guide synthetic efforts for lead optimization of tractable hits that are based on natural-product chemical motifs. Relevant findings for 7TM receptors (7TMRs), ion channels, class-7 transferases (protein kinases), hydrolases, and oxidoreductases will be discussed. PMID:24518065

  19. NITROGEN LIMITATION INCREASES BREVETOXINS IN KARENIA BREVIS (DINOPHYCEAE): IMPLICATIONS FOR BLOOM TOXICITY(1).

    Science.gov (United States)

    Ransom Hardison, D; Sunda, William G; Wayne Litaker, R; Shea, Damian; Tester, Patricia A

    2012-08-01

    Laboratory and field measurements of the toxin content in Karenia brevis cells vary by >4-fold. These differences have been largely attributed to genotypic variations in toxin production among strains. We hypothesized that nutrient limitation of growth rate is equally or more important in controlling the toxicity of K. brevis, as has been documented for other toxic algae. To test this hypothesis, we measured cellular growth rate, chlorophyll a, cellular carbon and nitrogen, cell volume, and brevetoxins in four strains of K. brevis grown in nutrient-replete and nitrogen (N)-limited semi-continuous cultures. N-limitation resulted in reductions of chlorophyll a, growth rate, volume per cell and nirtogen:carbon (N:C) ratios as well as a two-fold increase (1%-4% to 5%-9%) in the percentage of cellular carbon present as brevetoxins. The increase in cellular brevetoxin concentrations was consistent among genetically distinct strains. Normalizing brevetoxins to cellular volume instead of per cell eliminated much of the commonly reported toxin variability among strains. These results suggest that genetically linked differences in cellular volume may affect the toxin content of K. brevis cells as much or more than innate genotypic differences in cellular toxin content per unit of biomass. Our data suggest at least some of the >4-fold difference in toxicity per cell reported from field studies can be explained by limitation by nitrogen or other nutrients and by differences in cell size. The observed increase in brevetoxins in nitrogen limited cells is consistent with the carbon:nutrient balance hypothesis for increases in toxins and other plant defenses under nutrient limitation. PMID:27008996

  20. Stenosing tenosynovitis of the peroneus brevis tendon associated with hypertrophy of the peroneal tubercle.

    Science.gov (United States)

    Boya, Hakan; Pinar, Halit

    2010-01-01

    Stenosing peroneal tenosynovitis is not an uncommon ailment. It has a number of different causes, one of which is hypertrophy of the peroneal tubercle. In this report, we present a case of stenosing tenosynovitis of the peroneus brevis tendon associated with hypertrophy of the peroneal tubercle without involvement of the peroneus longus tendon. The condition was fully resolved by means of operative treatment. PMID:20188282

  1. Prediction of the pull-out strength of chemical anchors in natural stone

    Directory of Open Access Journals (Sweden)

    L. Contrafatto

    2014-07-01

    Full Text Available The applicability of some numerical models for the prediction of the failure mechanism and of the bearing capacity of post-installed threaded rods chemically anchored in basalt, sandstone and limestone is investigated, as well as the reliability of theoretical formulations conceived for concrete. The numerical predictions, performed by means of engineering structural analysis software and advanced numerical codes, are compared with the results of an experimental research related to chemical anchors in natural stone. The minimum embedment depth for such fastening system is identified.

  2. Restoration of thumb opposition by transposing the flexsor pollicis brevis muscle: thirteen-year clinical application

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Background To repair late median nerve injury, many methods have been used in the past years. The aim of this study was to review a thirteen-year experience in restoration of thumb opposition by transposing flexor pollicis brevis muscle.Methods From July 1992 to August 2005, 63 patients without thumb opposition because of late median never injury were treated by transposing the flexor pollicis brevis muscle. All the patients had received primary nerve repair after the jnjury. The interval between the injury and the second operation was (1.87±2.31) years (6 months to 4.2 years). The patients were followed up for 3 to 48 [months mean (22.93±2.31) months]. A functional evaluation system designed in 1992 were used to estimate the outcomes of the patients. Results All the patients gained excellent functional results without complications and disabilities during follow-up.Conclusions Restoration of thumb opposition by transposing flexsor pollicis brevis muscle has the following advantages: 1. Operative trauma is minimal; 2. It is not necessary to transpose other tendons; 3. Except for the thumb in opposition, movements of other fingers and the wrist are not restricted postoperatively.

  3. Osmotic stress does not trigger brevetoxin production in the dinoflagellate Karenia brevis.

    Science.gov (United States)

    Sunda, William G; Burleson, Cheska; Hardison, D Ransom; Morey, Jeanine S; Wang, Zhihong; Wolny, Jennifer; Corcoran, Alina A; Flewelling, Leanne J; Van Dolah, Frances M

    2013-06-18

    With the global proliferation of toxic harmful algal bloom species, there is a need to identify the environmental and biological factors that regulate toxin production. One such species, Karenia brevis, forms nearly annual blooms that threaten coastal regions throughout the Gulf of Mexico. This dinoflagellate produces brevetoxins, which are potent neurotoxins that cause neurotoxic shellfish poisoning and respiratory illness in humans, as well as massive fish kills. A recent publication reported that a rapid decrease in salinity increased cellular toxin quotas in K. brevis and hypothesized that brevetoxins serve a role in osmoregulation. This finding implied that salinity shifts could significantly alter the toxic effects of blooms. We repeated the original experiments separately in three different laboratories and found no evidence for increased brevetoxin production in response to low-salinity stress in any of the eight K. brevis strains we tested, including three used in the original study. Thus, we find no support for an osmoregulatory function of brevetoxins. The original publication also stated that there was no known cellular function for brevetoxins. However, there is increasing evidence that brevetoxins promote survival of the dinoflagellates by deterring grazing by zooplankton. Whether they have other as-yet-unidentified cellular functions is currently unknown.

  4. 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. PMID:27386392

  5. Biosorption and biodegradation of pyrene by Brevibacillus brevis and cellular responses to pyrene treatment.

    Science.gov (United States)

    Liao, Liping; Chen, Shuona; Peng, Hui; Yin, Hua; Ye, Jinshao; Liu, Zehua; Dang, Zhi; Liu, Zhichen

    2015-05-01

    Biodegradation has been proposed as an effective approach to remove pyrene, however, the information regarding cellular responses to pyrene treatment is limited thus far. In this study, the biodegradation and biosorption of pyrene by Brevibacillus brevis, along with cellular responses caused by pollutant were investigated by means of flow cytometry assay and scanning electron microscopy. The experimental results showed that pyrene was initially adsorbed by B. brevis and subsequently transported and intracellularly degraded. During this process, pyrene removal was primarily dependent on biodegradation. Cell invagination and cell surface corrugation occurred due to pyrene exposure. Nevertheless, cell regrowth after 96h treatment was observed, and the proportion of necrotic cell was only 2.8% after pyrene exposure for 120h, confirming that B. brevis could utilize pyrene as a sole carbon source for growth. The removal and biodegradation amount of pyrene (1mg/L) at 168h were 0.75 and 0.69mg/L, respectively, and the biosorption amount by inactivated cells was 0.41mg/L at this time.

  6. 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. PMID:26187837

  7. Polyphosphate Derived from Lactobacillus brevis Inhibits Colon Cancer Progression Through Induction of Cell Apoptosis.

    Science.gov (United States)

    Sakatani, Aki; Fujiya, Mikihiro; Ueno, Nobuhiro; Kashima, Shin; Sasajima, Junpei; Moriichi, Kentaro; Ikuta, Katsuya; Tanabe, Hiroki; Kohgo, Yutaka

    2016-02-01

    Although probiotics are known to have antitumor activity, few bacteria-derived antitumor molecules have been identified. The present study explored an antitumor molecule derived from Lactobacillus brevis SBL8803 (L. brevis 8803) and the mechanisms that underlie its effects. Cell viability and apoptosis were assessed by a sulforhodamine B assay and terminal deoxynucleotidyl transferase dUTP staining, respectively. Phosphorylated extracellular signal-regulated kinase (ERK) and cleaved poly ADP-ribose polymerase (PARP) expression were detected by western blotting. The conditioned medium of L. brevis 8803 inhibited SW620 cells viability and the effect was reduced by the degradation of polyphosphate (poly P) in the conditioned medium. A xenograft model showed that poly P inhibited the growth of SW620 cells. Poly P induced the apoptosis of SW620 cells through activation of the ERK pathway. In contrast, in primary cultured cells derived from normal mouse, poly P did not affect cell viability. Probiotic-derived poly P is expected to be an antitumor drug with fewer adverse effects than conventional drugs. PMID:26851013

  8. Survey of marine natural product structure revisions: a synergy of spectroscopy and chemical synthesis.

    Science.gov (United States)

    Suyama, Takashi L; Gerwick, William H; McPhail, Kerry L

    2011-11-15

    The structural assignment of new natural product molecules supports research in a multitude of disciplines that may lead to new therapeutic agents and or new understanding of disease biology. However, reports of numerous structural revisions, even of recently elucidated natural products, inspired the present survey of techniques used in structural misassignments and subsequent revisions in the context of constitutional or configurational errors. Given the comparatively recent development of marine natural products chemistry, coincident with modern spectroscopy, it is of interest to consider the relative roles of spectroscopy and chemical synthesis in the structure elucidation and revision of those marine natural products that were initially misassigned. Thus, a tabulated review of all marine natural product structural revisions from 2005 to 2010 is organized according to structural motif revised. Misassignments of constitution are more frequent than perhaps anticipated by reliance on HMBC and other advanced NMR experiments, especially when considering the full complement of all natural products. However, these techniques also feature prominently in structural revisions, specifically of marine natural products. Nevertheless, as is the case for revision of relative and absolute configuration, total synthesis is a proven partner for marine, as well as terrestrial, natural products structure elucidation. It also becomes apparent that considerable 'detective work' remains in structure elucidation, in spite of the spectacular advances in spectroscopic techniques.

  9. A study of suitability of some conventional chemical preservatives and natural antimicrobial compounds in allelopathic research

    Directory of Open Access Journals (Sweden)

    Plamen Marinov-Serafimov

    2015-12-01

    Full Text Available The impact of three conventional chemical preservatives (sodium benzoate, potassium sorbate and salicylic acid and a natural antimicrobial compound (thymol on germination, dynamics of growth and accumulation of fresh biomass (g per seedling of Lactuca sativa L., cultivar Great Lakes, was studied under laboratory conditions. The tested conventional chemical preservatives demonstrated strong inhibitory effects (GI 27.1-0.0% on germination and initial development of L. sativa, and they cannot be used in allelopathic studies in the laboratory. An addition of thymol at 0.5-1.0 ‰ concentration showed no inhibitory effect (GI varied 81.7-84.6% on germination and initial development of L. sativa. Thymol can therefore be used as a natural antimicrobial compound in allelopathic studies in the laboratory.

  10. 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.

  11. Comparative study of synthesised hydroxyapatite from pure chemicals and Malaysian natural limestone precursors

    International Nuclear Information System (INIS)

    Hydroxyapatite, (HA; Ca10(PO4)6(OH)2) has been successfully applied in medical and dental applications for several years due to its excellent biocompatibility. The usage of HA in Malaysia, however, is limited due to the lack of availability. Therefore the aim of this work is to produce HA materials from both pure chemicals and from Malaysian natural limestone precursors, and to compare their bulk properties. However, parts of Malaysian natural limestone deposits actually consist of a combination of Ca(OH)2 and CaCO3. In order to utilise the limestone to produce HA material, the combination of these commercially pure chemicals as HA precursors should still work. In order to test this hypothesis, two HAs were produced by wet synthesis technique utilising (a) combination of Ca(OH)2 + CaCO3 from pure commercial chemicals [WCCj and (b) a local natural limestone [WLI precursors. The HAs produced; WCC and WL, were compacted into discs and sintered at 1250 degree C. The characterisations and evaluations conducted were XRD, SEM-EDX, FTIR and shrinkage factor. The results indicate that WL gives slightly better bulk properties compared to WCC. (Author)

  12. Magnesium isotope fractionation by chemical diffusion in natural settings and in laboratory analogues

    Science.gov (United States)

    Chopra, Rahul; Richter, Frank M.; Bruce Watson, E.; Scullard, Christian R.

    2012-07-01

    Laboratory experiments are used to document isotopic fractionation of magnesium by chemical diffusion in a silicate melt and the results compared to the magnesium isotopic composition across contacts between igneous rocks of different composition in natural settings. The natural samples are from transects from felsic to mafic rocks at Vinal Cove in the Vinalhaven Intrusive Complex, Maine and from the Aztec Wash pluton in Nevada. Two laboratory diffusion couples made by juxtaposing melts made from powders of the felsic and mafic compositions sampled at Vinal Cove were annealed at about 1500 °C for 22.5 and 10 h, respectively. The transport of magnesium in the diffusion couples resulted in easily measured magnesium isotopic fractionations at the interface (δ26Mg∼1.5‰). These isotopic fractionations provide a distinctive isotopic “fingerprint” that we use to determine whether chemical gradients in natural settings where melts of different composition were juxtaposed were due to chemical diffusion. The magnesium isotopic fractionation along one profile at Vinal Cove is exactly what one would expect based on the fractionations found in the laboratory experiments. This is an important result in that it shows that the isotope fractionation by chemical diffusion found in highly controlled laboratory experiments can be found in a natural setting. This correspondence implies that chemical diffusion was the dominant process responsible for the transport of magnesium across this particular contact at Vinal Cove. A second Vinal Cove profile has a very similar gradient in magnesium concentration but with significantly less magnesium isotopic fractionation than expected. This suggests that mass transport at this location was only partly by diffusion and that some other mass transport mechanism such as mechanical mixing must have also played a role. The magnesium isotopic composition of samples from Aztec Wash shows no resolvable isotopic fractionation across the contact

  13. Non-Natural Sugar Analogues: Chemical Probes for Metabolic Oligosaccharide Engineering

    Science.gov (United States)

    Aich, Udayanath; Yarema, Kevin J.

    Metabolic oligosaccharide engineering (MOE) is a rapidly growing technology emerging from the field of chemical biology that allows novel chemical functionalities to be biosynthetically installed into the carbohydrates of living cells and animals. Since pioneering efforts to modulate sialic acid display through the use of non-natural N-acetyl-D-mannosamine (ManNAc) analogues were reported 15 years ago, monosaccharide probes have been developed to manipulate N-acetyl-D-galactosamine (GalNAc), N-acetyl-D-glucosamine (GlcNAc), and fucose-containing glycans. The 'first generation' of analogues, comprised of a series of ManNAc derivatives with elongated N-acyl chains, demonstrated pathway permissivity and the ability of this methodology to impinge on biological processes ranging from pathogen binding to gene expression and cell adhesion. Later analogues have incorporated chemical function groups including ketones, azides, thiols, and alkyne not normally found in carbohydrates. These groups serve as 'tags' for the subsequent use of chemoselective ligation reactions to further elaborate the chemical properties of the cell surface and thereby greatly expand the potential of MOE technology to offer control over biological processes.

  14. Sorption and desorption of Fe(III) on natural and chemically modified zeolite

    International Nuclear Information System (INIS)

    The Fe(III) uptake from aqueous solutions by natural and chemically modified zeolites was investigated using a gradual radioexchange method and AAS technique. The leachability of Fe(III) from loaded zeolites was studied too. The Fe-uptake reached the value of 60 mg x g-1 for the zeolite chemically treated with 6 mol x l-1 solution of NaOH and it is more than twelve times higher than that of the raw zeolite. The leachability of the loaded zeolite samples in water and alkaline solution was up 5%. The leachability of the same zeolites in acid solution depended on the concentration of modifying solution. The leachability at pH = 2.6 in the range 2-20% at pH = 1.9 was many times higher. The results of the radioexchange and AAS methods were compared. (author)

  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. Chemical Potential and the Nature of the Dark Energy: The case of phantom

    CERN Document Server

    Lima, J A S

    2008-01-01

    The influence of a possible non zero chemical potential $\\mu$ on the nature of dark energy is investigated by assuming that the dark energy is a relativistic perfect simple fluid obeying the equation of state (EoS), $p=\\omega \\rho$ ($\\omega 0$, the $\\omega$-parameter must be greater than -1 (vacuum is forbidden) while for $\\mu 0$ are permmited only if $-1 < \\omega < -1/2$. The thermodynamics and statistical arguments constrain the EoS parameter to be $\\omega < -1/2$, a result surprisingly close to the maximal value required to accelerate a FRW type universe dominated by matter and dark energy ($\\omega \\lesssim -10/21$).

  17. Form and function of the fibularis brevis muscle in some passerine birds

    OpenAIRE

    Moreno Mañas, Eulalia

    1990-01-01

    The morphology of the fibularis brevis muscle was analysed in 29 passerine species. As expected, most of them showed onl y one point of origin, the head arising crani all y from the f ibul a and th e adj acent tibiotarsus. However, Panurus hiarmicus, Regulus regulus. Parusater. P. caeruleus. Cerrhiafamiliaris and C. hrach)'dacty/a showed an extra point 01' ori gin, with fl eshy fibres ari s ing from the outer cnemial crest of the tibiotarsus. The occurrence of such a tibi al head was compared...

  18. Transcriptomic response of the red tide dinoflagellate, Karenia brevis, to nitrogen and phosphorus depletion and addition

    Directory of Open Access Journals (Sweden)

    Johnson Jillian G

    2011-07-01

    Full Text Available Abstract Background The role of coastal nutrient sources in the persistence of Karenia brevis red tides in coastal waters of Florida is a contentious issue that warrants investigation into the regulation of nutrient responses in this dinoflagellate. In other phytoplankton studied, nutrient status is reflected by the expression levels of N- and P-responsive gene transcripts. In dinoflagellates, however, many processes are regulated post-transcriptionally. All nuclear encoded gene transcripts studied to date possess a 5' trans-spliced leader (SL sequence suggestive, based on the trypanosome model, of post-transcriptional regulation. The current study therefore sought to determine if the transcriptome of K. brevis is responsive to nitrogen and phosphorus and is informative of nutrient status. Results Microarray analysis of N-depleted K. brevis cultures revealed an increase in the expression of transcripts involved in N-assimilation (nitrate and ammonium transporters, glutamine synthetases relative to nutrient replete cells. In contrast, a transcriptional signal of P-starvation was not apparent despite evidence of P-starvation based on their rapid growth response to P-addition. To study transcriptome responses to nutrient addition, the limiting nutrient was added to depleted cells and changes in global gene expression were assessed over the first 48 hours following nutrient addition. Both N- and P-addition resulted in significant changes in approximately 4% of genes on the microarray, using a significance cutoff of 1.7-fold and p ≤ 10-4. By far, the earliest responding genes were dominated in both nutrient treatments by pentatricopeptide repeat (PPR proteins, which increased in expression up to 3-fold by 1 h following nutrient addition. PPR proteins are nuclear encoded proteins involved in chloroplast and mitochondria RNA processing. Correspondingly, other functions enriched in response to both nutrients were photosystem and ribosomal genes

  19. [Electrically induced cutaneo-muscular reflex from the m. extensor digitorum brevis].

    Science.gov (United States)

    Piepenbrock, N; Hess, C W; Ludin, H P; Mumenthaler, M

    1987-06-01

    We recorded the cutaneo-muscular reflexes in 90 normal subjects from the extensor digitorum brevis muscle following electrical stimulation at the second toe. In 88 subjects an early and a late EMG response were obtained. The mean latency of the second reflex response was 91.9 +/- 12.1 ms and the mean duration was 27.3 +/- 11.6 ms. However, there was considerable variability of the interindividual amplitudes. Comparison of the age related changes in the latencies of the first and second reflexes yielded results consistent with the transcortical or spino-bulbo-spinal hypothesis. PMID:3111831

  20. Radiometric-microbiologic assay of niacin using Kloeckera brevis: analysis of human blood and food

    Energy Technology Data Exchange (ETDEWEB)

    Guilarte, T.R.; Pravlik, K.

    1983-12-01

    Kloeckera brevis, a yeast, was used as the test organism for the development of a radiometric-microbiologic (RMA) assay for niacin. The assay was determined to be sensitive to the 2 ng niacin per vial level and specific for the biologically active forms of this vitamin. The method was shown to be simple, accurate, and precise in the analysis of niacin in human blood and food. The application of the radiometric technique eliminates some of the problems encountered with conventional turbidimetric-microbiologic assay.

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

    Directory of Open Access Journals (Sweden)

    Michael Poulsen

    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.

  2. The effect of natural weathering on the chemical and isotopic compositions of biotites

    Science.gov (United States)

    Clauer, Norbert; O'Neil, J.R.; Bonnot-Courtois, C.

    1982-01-01

    The effect of progressive natural weathering on the isotopic (Rb-Sr, K-Ar, ??D, ??18O) and chemical (REE, H2O+) 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 1. (a) "protominerals" may form within the biotite structure during the initial period of weathering, and 2. (b) only when chemical equilibrium is approached in the weathering profile are new minerals able to form. ?? 1982.

  3. 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.

  4. 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…

  5. Resistance of pine, australian red cedar woods and their derivate products to Cryptotermes brevis attack

    Directory of Open Access Journals (Sweden)

    Marcelo Xisto Ribeiro

    2014-09-01

    Full Text Available The aim of this work was to compare the resistance of Australian red cedar (Toona ciliata and pine (Pinus sp. woods and particleboards made from these species to dry-wood termite Cryptotermes brevis attack, as much as to quantify the mortality of the insects. 30 termite pseudo-workers were put in each 9,5 cm-diameter Petri dishes containing the samples (1,5 x 1,5 x 0,5 cm and cotton sheets positioned on the perforated covers, daily moisturized with 5 ml of water. The dishes were maintained in BOD (Biological Oxygen Demand at 24±5 ºC and 24 h of escotophase. A control sample without any feed source was included in the bioassay. The deterioration index (ID and mortality of the insects were evaluated after 60 days. Termites from the control sample presented higher termite mortality than the other treatments, which did not differ among each other. Toona ciliata wood was more resistant than Pinus sp. wood to Cryptotermes brevis attack. The average deterioration indexes were 1.74% and 6.62% respectively for those woods. The average deterioration index of the panels made with 100% Toona ciliata (ID=1.58% was similar to the deterioration index of particleboards made with this specie mixed with Pinus sp. (ID=1.87%.

  6. 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.

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

    Science.gov (United States)

    Zhao, Yu; Knøchel, Susanne; Siegumfeldt, Henrik

    2014-01-01

    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 de Man Rogosa Sharpe (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 Lactobacillus brevis strains. The results suggest that aerobic cultivation increased the oxidative stress tolerance in Lactobacillus 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. PMID:25505451

  8. Accuracy, Precision, and Reliability of Chemical Measurements in Natural Products Research

    Science.gov (United States)

    Betz, Joseph M.; Brown, Paula N.; Roman, Mark C.

    2010-01-01

    Natural products chemistry is the discipline that lies at the heart of modern pharmacognosy. The field encompasses qualitative and quantitative analytical tools that range from spectroscopy and spectrometry to chromatography. Among other things, modern research on crude botanicals is engaged in the discovery of the phytochemical constituents necessary for therapeutic efficacy, including the synergistic effects of components of complex mixtures in the botanical matrix. In the phytomedicine field, these botanicals and their contained mixtures are considered the active pharmaceutical ingredient (API), and pharmacognosists are increasingly called upon to supplement their molecular discovery work by assisting in the development and utilization of analytical tools for assessing the quality and safety of these products. Unlike single-chemical entity APIs, botanical raw materials and their derived products are highly variable because their chemistry and morphology depend on the genotypic and phenotypic variation, geographical origin and weather exposure, harvesting practices, and processing conditions of the source material. Unless controlled, this inherent variability in the raw material stream can result in inconsistent finished products that are under-potent, over-potent, and/or contaminated. Over the decades, natural products chemists have routinely developed quantitative analytical methods for phytochemicals of interest. Quantitative methods for the determination of product quality bear the weight of regulatory scrutiny. These methods must be accurate, precise, and reproducible. Accordingly, this review discusses the principles of accuracy (relationship between experimental and true value), precision (distribution of data values), and reliability in the quantitation of phytochemicals in natural products. PMID:20884340

  9. Antimycobacterial activity of chemically defined natural substances from the Caribbean flora in Guadeloupe.

    Science.gov (United States)

    Rastogi, N; Abaul, J; Goh, K S; Devallois, A; Philogène, E; Bourgeois, P

    1998-04-01

    Eight chemically defined, naturally occurring compounds were extracted from the tropical flora of the Caribbean island of Guadeloupe: pilocarpine, an alkaloid from Pilocarpus racemosus; heraclenol and isomeranzin, coumarins from Triphasia trifolia; lochnerin, an indole alkaloid from Rauwolfia biauriculata; ibogaine and voacangine, indole alkaloids from Tabernaemontana citrifolia; texalin, an oxazole from Amyris elemifera; and canellal, a sesquiterpene dialdehyde from Canella winterana. An essential oil fraction from Canella winterana was also tested. The antimycobacterial activity of these substances was tested against Mycobacterium tuberculosis, M. avium and M. kansasii using the Middlebrook 7H11 agar medium, the Bactec 460-TB radiometric methodology, and determination of bacterial viable counts. Three compounds, namely ibogaine, voacangine and texalin, showed antimycobacterial activity. Investigations on the structure-modification and structure-activity relationships of these compounds may help determine new targets for future drug development. PMID:9626931

  10. Adsorption and desorption of Cr(III) on natural and chemically modified Slovak zeolites

    International Nuclear Information System (INIS)

    Natural and chemically modified zeolites from the Slovak Republic and Ukraine have been investigated as the adsorbents for the uptake of Cr(III). Model water solution of low radioactivity was used. The adsorption and desorption kinetics of chromium were established with the gradual radioexchange technique (tracer 51Cr) and flame AAS. The effect of the factors studied are examined and explained. The sorption coefficient μ, distribution coefficient KD, sorption capacity Γ, sorption rate S, and leachability of Cr were calculated in neutral, alkaline and acidic aqueous solutions. The sorption capacity of the modified zeolites was found to be greater by a factor of 2 to 16 than that of the unmodified ones depending on the modifying solution applied. The leachability of chromium from loaded zeolites into the neutral solution was negligible. The leachability into alkaline and acidic solutions increased over 40%. (author)

  11. Fuel for thought: chemically powered nanomotors out-swim nature's flagellated bacteria.

    Science.gov (United States)

    Mirkovic, Tihana; Zacharia, Nicole S; Scholes, Gregory D; Ozin, Geoffrey A

    2010-04-27

    Half a century ago, Richard Feynman envisioned tiny machines able to perform chemistry by mechanical manipulation of atoms. While this vision has not yet been realized in practice, researchers have recently discovered how to use chemistry to drive tiny engines and to operate tiny machines in the liquid phase, in much the same way Nature uses biochemistry to power a myriad of biological motors and machines. Herein, we provide a brief Perspective on the rapidly growing research activity in the emerging field of chemically powered nanomotors and nanomachines, consider some of the challenges facing its continued rapid development, and imagine a future in which these tiny motors and machines can get down to doing some serious work.

  12. Susceptibility of gametes and embryos of the eastern oyster, Crassostrea virginica, to Karenia brevis and its toxins.

    Science.gov (United States)

    Rolton, Anne; Soudant, Philippe; Vignier, Julien; Pierce, Richard; Henry, Michael; Shumway, Sandra E; Bricelj, V Monica; Volety, Aswani K

    2015-06-01

    The bivalve mollusc, Crassostrea virginica, is frequently exposed to blooms of Karenia brevis along the west coast of Florida during periods of spawning and early larval development. A continuous 4-day exposure of gametes and 2-4 cell stage embryos of C. virginica to whole-cell and culture filtrate of K. brevis at 500 and 5000 cells mL(-1), was followed by a 4-day 'recovery' period. Larval growth, percent of normal, abnormal and dead larvae, and the presence of food in the larval gut were measured throughout the exposure period. Results suggest that negative effects mainly occur during embryogenesis and early development. Damage to feeding apparatus/gut may occur during embryonic development or exposure to toxins may act as a feeding deterrent on non-toxic algae. Following 2-h in vitro exposure of gametes, differences in oocyte and sperm cell parameters were investigated using flow cytometry. The reduced sperm viability in the whole-cell 5000 cells mL(-1) treatment suggests the involvement of extracellular brevetoxins (PbTx) and perhaps other harmful, uncharacterized compounds associated with the K. brevis cell membrane. The cumulative effects of reduced sperm viability, fertilization success, embryonic and larval survival, and the near-annual exposure to blooms of K. brevis could cause significant bottlenecks on oyster recruitment. PMID:25771241

  13. 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...

  14. 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...

  15. Contaminant and nutrient concentrations of natural ingredient rat and mouse diet used in chemical toxicology studies.

    Science.gov (United States)

    Rao, G N; Knapka, J J

    1987-08-01

    The NIH-07 open formula natural ingredient rat and mouse ration is the standard diet for chemical toxicity and carcinogenicity studies conducted for the National Toxicology Program (NTP). Contaminant and nutrient concentrations were determined in 2 to 94 lots of this diet used in the NTP toxicology studies. All nutrient concentrations were equivalent to or greater than the requirements for rats and mice as set forth by the National Research Council. Aflatoxins, Hg, chlorinated hydrocarbons except methoxychlor, organophosphates except malathion, estrogenic activity, and Salmonella sp. were not present at the detectable levels. Fluorine, As, Cd, Pb, Se, N-nitrosodimethylamine, N-nitrosopyrrolidine, N-nitrosomorpholine, nitrate, nitrite, butylated hydroxyanisole, butylated hydroxytoluene, ethylene dibromide, methoxychlor, malathion, and trypsin inhibitor activity were present at or above the detectable levels. Five lots of diet had nitrosamine content of 100 to 273 ppb and 7 lots had 2.08 to 3.37 ppm of Pb. All other lots of NIH-07 diet used for NTP toxicology studies contained low levels of the contaminants. After determination of the contaminant concentrations in the 94 lots of diet and the contaminant concentrations in natural ingredients used in formulating NIH-07 diet, maximum allowable levels of contaminants were established and a flexible scoring system for acceptability of each lot of diet for chemical toxicology studies was developed. By prescreening ingredients such as fish meal for heavy metals and nitrosamines, and applying the flexible scoring system proposed, more than 95% of the lots of NIH-07 diet produced during the last 3 years had scores of greater than or equal to 95 out of 100 points and were considered acceptable for toxicology studies.

  16. Porous chitosan scaffold cross-linked by chemical and natural procedure applied to investigate cell regeneration

    International Nuclear Information System (INIS)

    Highlights: ► Polymeric scaffolds, made from chitosan-based films fixed by chemical (citrate) or natural method (genipin), were developed. ► Nano-indentation with a constant harmonic frequency was applied on porous scaffolds to explore their surface mechanics. ► The relationship between surface mechanical property and cell-surface interactions of scaffold materials was demonstrated. ► Porous scaffolds cross-linked by genipin showed adequate cell affinity, non-toxicity, and suitable mechanical properties. - Abstract: Porous chitosan scaffold is used for tissue engineering and drug delivery, but is limited as a scaffold material due to its mechanical weakness, which restrains cell adhesion on the surface. In this study, a chemical reagent (citrate) and a natural reagent (genipin) are used as cross-linkers for the formation of chitosan-based films. Nanoindentation technique with a continuous stiffness measurement system is particularly applied on the porous scaffold surface to examine the characteristic modulus and nanohardness of a porous scaffold surface. The characteristic modulus of a genipin-cross-linked chitosan surface is ≈2.325 GPa, which is significantly higher than that of an uncross-linked one (≈1.292 GPa). The cell-scaffold surface interaction is assessed. The cell morphology and results of an MTS assay of 3T3-fibroblast cells of a genipin-cross-linked chitosan surface indicate that the enhancement of mechanical properties induced cell adhesion and proliferation on the modified porous scaffold surface. The pore size and mechanical properties of porous chitosan film can be tuned for specific applications such as tissue regeneration.

  17. Increased toxicity of Karenia brevis during phosphate limited growth: ecological and evolutionary implications.

    Directory of Open Access Journals (Sweden)

    Donnie Ransom Hardison

    Full Text Available Karenia brevis is the dominant toxic red tide algal species in the Gulf of Mexico. It produces potent neurotoxins (brevetoxins [PbTxs], which negatively impact human and animal health, local economies, and ecosystem function. Field measurements have shown that cellular brevetoxin contents vary from 1-68 pg/cell but the source of this variability is uncertain. Increases in cellular toxicity caused by nutrient-limitation and inter-strain differences have been observed in many algal species. This study examined the effect of P-limitation of growth rate on cellular toxin concentrations in five Karenia brevis strains from different geographic locations. Phosphorous was selected because of evidence for regional P-limitation of algal growth in the Gulf of Mexico. Depending on the isolate, P-limited cells had 2.3- to 7.3-fold higher PbTx per cell than P-replete cells. The percent of cellular carbon associated with brevetoxins (%C-PbTx was ~ 0.7 to 2.1% in P-replete cells, but increased to 1.6-5% under P-limitation. Because PbTxs are potent anti-grazing compounds, this increased investment in PbTxs should enhance cellular survival during periods of nutrient-limited growth. The %C-PbTx was inversely related to the specific growth rate in both the nutrient-replete and P-limited cultures of all strains. This inverse relationship is consistent with an evolutionary tradeoff between carbon investment in PbTxs and other grazing defenses, and C investment in growth and reproduction. In aquatic environments where nutrient supply and grazing pressure often vary on different temporal and spatial scales, this tradeoff would be selectively advantageous as it would result in increased net population growth rates. The variation in PbTx/cell values observed in this study can account for the range of values observed in the field, including the highest values, which are not observed under N-limitation. These results suggest P-limitation is an important factor regulating

  18. Chemical and isotopic compositions of natural gases from the Japanese major oil and gas fields

    International Nuclear Information System (INIS)

    Carbon isotopic ratios (13C/12C) and chemical compositions of methane (C1), ethane (C2), propane (C3), i-butane (i-C4) and n-butane (n-C4) were measured for natural gases from the Japanese major oil and gas fields. The C1/(C2+C3) vs. δ13C(C1) plot suggests that most samples analyzed in the present study are of thermogenic origin with a minor contribution of biogenic gases. Some gases show unusually high ratios of C2/C3 and i-C4/n-C4, and low ratios cf C3/i-C4 (Unusual-Hydrocarbon-Ratio gases: UHR gases). The carbon isotopic ratios and hydrocarbon compositions strongly suggest that these unusual ratios were caused by the chromatographic effect of sediments during migration of the gases. By comparing hydrocarbon ratios (C1/C2, C2/C3, C2/i-C4, C2/n-C4, C3/i-C4, C3/n-C4 and i-C4/n-C4) of the UHR and normal gases, it was found that the natural gases tend to lose their hydrocarbons during migration in the order: n-C4 ≅ C3 > C2 ≅ i-C4 > C1. (author)

  19. 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.

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

    Science.gov (United States)

    Ramos, Cíntia Lacerda; Thorsen, Line; Schwan, Rosane Freitas; Jespersen, Lene

    2013-10-01

    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 fermentum (34 isolates), Lactobacillus plantarum (10) and Lactobacillus brevis (7). Based on being either highly tolerant to bile, showing an ability for auto-aggregation and/or hydrophobic properties, one L. fermentum (CH58), three L. plantarum (CH3, CH41 and SAU96) and two L. brevis (SAU105 and FFC199) were selected. The highest co-aggregation ability with Escherichia coli was observed to L. plantarum CH41. L. brevis SAU105 and FFC199 and L. fermentum CH58 exhibited antagonistic activity towards the pathogens Listeria monocytogenes and Staphylococcus aureus. L. plantarum CH3 and CH41 and L. brevis 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 < 0.05). The present work showed 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.

  1. Treatment of Cryptotermes brevis infestations in furniture with heat, solid fumigants and inert gases

    OpenAIRE

    Borges, Annabella; Guerreiro, Orlando; Ferreira, Maria T.; Myles, Timothy G.; Borges, Paulo A.V.

    2007-01-01

    A Cryptotermes brevis é uma térmita extraordinária na sua capacidade única de atacar madeira extremamente seca. É, igualmente, extraordinária na capacidade de atacar uma grande variedade de tipos de madeira, o que nos leva a concluir como sendo a única espécie de térmitas que é facilmente encontrada em mobílias. Como tal, é muito fácil a sua dispersão aquando do transporte de mobílias infestadas, de lugar para lugar, e esta é uma das principais razões pela qual esta térmita consegue ter uma d...

  2. 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.

  3. 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.

  4. Chemical constituents of Chinese natural medicine, morindae radix, the dried roots of morinda officinalis how.: structures of morindolide and morofficinaloside.

    Science.gov (United States)

    Yoshikawa, M; Yamaguchi, S; Nishisaka, H; Yamahara, J; Murakami, N

    1995-09-01

    A new iridoid lactone, morindolide, and a new iridoid glucoside, morofficinaloside, have been isolated from a Chinese natural medicine, Morindae Radix, the dried root of Morinda officinalis How. together with a number of known compounds: five anthraquinones, four iridoid glucosides, a monoterpene glycoside, two sterols, an ursane-type triterpene, and a lactone compound. The chemical structures of the new compounds were determined on the basis of chemical and physicochemical evidence. PMID:7586069

  5. Chemical nature of boron and nitrogen dopant atoms in graphene strongly influences its electronic properties.

    Science.gov (United States)

    Lazar, Petr; Zbořil, Radek; Pumera, Martin; Otyepka, Michal

    2014-07-21

    Boron and nitrogen doped graphenes are highly promising materials for electrochemical applications, such as energy storage, generation and sensing. The doped graphenes can be prepared by a broad variety of chemical approaches. The substitution of a carbon atom should induce n-type behavior in the case of nitrogen and p-type behavior in the case of boron-doped graphene; however, the real situation is more complex. The electrochemical experiments show that boron-doped graphene prepared by hydroboration reaction exhibits similar properties as the nitrogen doped graphene; according to theory, the electrochemical behavior of B and N doped graphenes should be opposite. Here we analyze the electronic structure of N/B-doped graphene (at ∼5% coverage) by theoretical calculations. We consider graphene doped by both substitution and addition reactions. The density of states (DOS) plots show that graphene doped by substitution of the carbon atom by N/B behaves as expected, i.e., as an n/p-doped material. N-doped graphene also has a lower value of the workfunction (3.10 eV) with respect to that of the pristine graphene (4.31 eV), whereas the workfunction of B-doped graphene is increased to the value of 5.57 eV. On the other hand, the workfunctions of graphene doped by addition of -NH2 (4.77 eV) and -BH2 (4.54 eV) groups are both slightly increased and therefore the chemical nature of the dopant is less distinguishable. This shows that mode of doping depends significantly on the synthesis method used, as it leads to different types of behaviour, and, in turn, different electronic and electrochemical properties of doped graphene, as observed in electrocatalytic experiments. This study has a tremendous impact on the design of doped graphene systems from the point of view of synthetic chemistry.

  6. Runoff rates, chemical speciation and bioavailability of copper released from naturally patinated copper.

    Science.gov (United States)

    Karlén, C; Wallinder, I Odnevall; Heijerick, D; Leygraf, C

    2002-01-01

    The release of copper, induced by atmospheric corrosion, from naturally patinated copper of varying age (0 and 30 years) has been investigated together with its potential ecotoxic effect. Results were generated in an interdisciplinary research effort in which corrosion science and ecotoxicology aspects were combined. The aim of the investigation was to elucidate the situation when copper-containing rainwater leaves a roof in terms of runoff rate, chemical speciation, bioavailability and ecotoxicity effects. Data have been collected during a three-year field exposure conducted in the urban environment of Stockholm, Sweden. The potential environmental effects have been evaluated using a combination of a copper specific biosensor test with the bacterium Alcaligenes eutrophus and the conventional 72-h growth inhibition test with the green alga Raphidocelis subcapitata. The results show annual runoff rates between 1.0 and 1.5 g/m2 year for naturally patinated copper of varying age. The runoff rate increased slightly with patina age, which mainly is attributed to the enhanced first flush effect observed on thicker patina layers. The total copper concentration in investigated runoff samplings ranged from 0.9 to 9.7 mg/l. Both computer modeling and experimental studies revealed that the majority (60-100%) of released copper was present as the free hydrated cupric ion, Cu(H2O)6(2+), the most bioavailable copper species. However, other copper species in the runoff water, such as, e.g. Cu(OH)+ and Cu2(OH)2(2+), were also bioavailable. The copper-containing runoff water, sampled directly after release from the roof, caused significant reduction in growth rate of the green alga. It should be emphasized that the results describe the runoff situation immediately after release from the copper roof and not the real environmental ecotoxicity. Therefore the data should only be used as an initial assessment of the potential environmental effect of copper runoff from building

  7. Electronic structure and chemical bond nature in Cs2PuO2Cl4

    Directory of Open Access Journals (Sweden)

    Teterin Yury A.

    2015-01-01

    Full Text Available X-ray photoelectron spectral analysis of dicaesiumtetrachlorodioxoplutonate (Cs2PuO2Cl4 single crystal was done in the binding energy range 0-~35 eV on the basis of binding energies and structure of the core electronic shells (~35 eV-1250 eV, as well as the relativistic discrete variation calculation results for the PuO2Cl4 (D4h. This cluster reflects Pu close environment in Cs2PuO2Cl4 containing the plutonyl group PuO2. The many-body effects due to the presence of cesium and chlorine were shown to contribute to the outer valence (0-~15 eV binding energy spectral structure much less than to the inner valence (~15 eV- ~35 eV binding energy one. The filled Pu 5f electronic states were theoretically calculated and experimentally con- firmed to present in the valence band of Cs2PuO2Cl4. It corroborates the suggestion on the direct participation of the Pu 5f electrons in the chemical bond. The Pu 6p atomic orbitals were shown to participate in formation of both the inner and the outer valence molecular orbitals (bands, while the filled Pu 6p and O 2s, Cl 3s electronic shells were found to take the largest part in formation of the inner valence molecular orbitals. The composition of molecular orbitals and the sequence order in the binding energy range 0-~35 eV in Cs2PuO2Cl4 were established. The quantitative scheme of molecular orbitals for Cs2PuO2Cl4 in the binding energy range 0-~15 eV was built on the basis of the experimental and theoretical data. It is fundamental for both understanding the chemical bond nature in Cs2PuO2Cl4 and the interpretation of other X-ray spectra of Cs2PuO2Cl4. The contributions to the chemical binding for the PuO2Cl4 cluster were evaluated to be: the contribution of the outer valence molecular orbitals -66 %, the contribution of the inner valence molecular orbitals -34 %.

  8. Chemical features of soils in a natural forest of West Hungary

    Science.gov (United States)

    Hofmann, Eszter; Bidló, András

    2015-04-01

    The present research focuses on the chemical results of soils formed on miocene carbonate rocks in a natural forest of West Hungary. Soil profiles derived from the Szárhalom Forest, located near the Lake Fertő, next to the city of Sopron. Six soil profiles were opened and analysed in this area. In the field the following physical parameters were evaluated from the soil profiles: transition, structure, compactness, roots, skeletal percent, colour, physical assortment, concretion and soil defect. Laboratory analysis involved the measurement of acidity, particle distribution, carbonated lime content, humus content, ammonium lactate-acetic acid soluble phosphorus- and potassium content, potassium chloride soluble calcium- and magnesium content, ethylene-diamine-tetraacetic-acid (EDTA) and diethylene-triamine-pentaacetic-acid (DTPA) soluble copper-, iron-, manganese- and zinc contents. These soils formed under a hornbeam-oak forest climate mainly and under a beech forest climate diffusely. The location and climate of the sites forms a basis of the comparison of the soils with similar base rock. The formation of the acidic and humus-rich upper layer of the soil profiles is influenced by the mineral composition and the weathering of the rocks. X-ray diffraction (Philips P W3710/PW1050 type X-ray diffractometer), thermoanalytical measurements (Mettler Toledo TGA/DSC 1 type thermogravimeter) and ICP-OES (Thermo Scientific iCAP 7000 Series) were also carried out to determine the mineral composition of the soils and the content of heavy metals. The soil samples were collected with both traditional and undisturbed (using the Kubiena box) sampling methods to enable further micromorphological investigations as well. The research is supported by the "Agroclimate-2" (VKSZ_12-1-2013-0034) joint EU-national research project. Key words: Natural forest, Miocene limestone, Mineral composition, Thermal analysis, Micromorphology

  9. Comparison of Some Chemical Contents of Ganoderma lucidum (Curtis P. Karst Collected from Nature and Cultured on Orange Stump

    Directory of Open Access Journals (Sweden)

    Nezahat Turfan

    2016-03-01

    Full Text Available Ganoderma lucidum (Curtis P. Karst (Reishi mushroom is one of medicinal mushroom species. The chemical content of the mushrooms shows significant changes depending on the physical and chemical properties of their growing place. In this study; total soluble protein, total soluble carbohydrate (glucose, fructose and sucrose and some mineral elements (P, K, Mg, Mn, S, Fe, Zn, Ca and Na of Ganoderma lucidum collected from the nature and cultured on orange stump were investigated. According to the results; total protein, glucose, fructose, sucrose and starch content of the G. lucidum cultured on orange stump were found higher than G. lucidum collected from nature. Phosphorus, iron, sodium, potassium and sulfur content were determined to be higher in mushroom samples cultured on orange stump. Calcium, magnesium, manganese and zinc values were found as higher in mushroom samples collected from nature. According to these results, G. lucidum cultured on orange stump had higher nutritional value than mushrooms collected from nature.

  10. 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.

  11. Chemical Reactivity Probes for Assessing Abiotic Natural Attenuation by Reducing Iron Minerals.

    Science.gov (United States)

    Fan, Dimin; Bradley, Miranda J; Hinkle, Adrian W; Johnson, Richard L; Tratnyek, Paul G

    2016-02-16

    Increasing recognition that abiotic natural attenuation (NA) of chlorinated solvents can be important has created demand for improved methods to characterize the redox properties of the aquifer materials that are responsible for abiotic NA. This study explores one promising approach: using chemical reactivity probes (CRPs) to characterize the thermodynamic and kinetic aspects of contaminant reduction by reducing iron minerals. Assays of thermodynamic CRPs were developed to determine the reduction potentials (ECRP) of suspended minerals by spectrophotometric determination of equilibrium CRP speciation and calculations using the Nernst equation. ECRP varied as expected with mineral type, mineral loading, and Fe(II) concentration. Comparison of ECRP with reduction potentials measured potentiometrically using a Pt electrode (EPt) showed that ECRP was 100-150 mV more negative than EPt. When EPt was measured with small additions of CRPs, the systematic difference between EPt and ECRP was eliminated, suggesting that these CRPs are effective mediators of electron transfer between mineral and electrode surfaces. Model contaminants (4-chloronitrobenzene, 2-chloroacetophenone, and carbon tetrachloride) were used as kinetic CRPs. The reduction rate constants of kinetic CRPs correlated well with the ECRP for mineral suspensions. Using the rate constants compiled from literature for contaminants and relative mineral reduction potentials based on ECRP measurements, qualitatively consistent trends were obtained, suggesting that CRP-based assays may be useful for estimating abiotic NA rates of contaminants in groundwater. PMID:26814150

  12. Freeze-thaw performance of chemically stabilized natural and recycled highway materials

    Institute of Scientific and Technical Information of China (English)

    Tuncer B Edil; Bora Cetin

    2015-01-01

    This article provides an overview of several previous studies that investigated the stiffness and strength performance of chemically stabilized roadway materials under winter conditions (freeze-thaw cycling). The objective of this research was to understand the behavior of different materials stabilized with different type of binders when they were subjected to freeze-thaw cycling. Nine different materials including natural soils (organic soil, clay, silt, sand, and road surface gravel), reclaimed pavement material, and recycled asphalt pavement stabilized with nine different binders (five different fly ashes, lime, cement, lime kiln dust, cement kiln dust) were discussed. This article investigated how the volume, resilient modulus and unconfined compressive strength of soils/materials stabilized with different binders change in response to freeze-thaw cycling. Overall, the review results indicate that the stiffness and strength of all stabilized materials decrease somewhat with freeze-thaw cycling. However, the reduced strength and stiffness of stabilized materials after freeze-thaw cycling was still higher than that of unstabilized-unfrozen original soils and materials. In addition, materials stabilized with cement kiln dust provided the best performance against freeze-thaw cycling.

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

    Science.gov (United States)

    Latorraca, João V F; Dünisch, Oliver; Koch, Gerald

    2011-09-01

    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. PMID:21779654

  14. Efficacy of Rodent Control in Alfalfa and Wheat Crops Using Chemical and Natural Rodenticides

    Directory of Open Access Journals (Sweden)

    Suzana Đedović

    2007-01-01

    Full Text Available Biological efficacy of chemical and natural rodenticides in controlling rodents in alfalfa and wheat crops was investigated. The experiment was set up using a randomized block design with four replicates and 400 m2 plots in compliace with a standard OEPP/EPPO method. Examination was based on the average number of active holes and rodenticide efficacy was measured three, seven, 14 and 28 days after treatment. Rodent numbers were computed from the number of active holes, and rodenticide efficacy using Abbott’s formula.The appearance and arrangement of active holes indicated the presence of common vole (Microtus arvalis Pall and striped field mouse (Apodemus agrarius in the plots. The products tested demonstrated satisfactory efficacy in controlling rodents in alfalfa and wheatcrops. Products based on vitamin D3 achieved 87-90% efficacy in both crops. The efficacy of a bromadiolone-based product ranged from 84% to 90%, while a cellulose product displayed the highest variation in efficacy, ranging from 86% to 98%.

  15. EPR study into the nature of Cu(2)-anion chemical bond in glass

    International Nuclear Information System (INIS)

    Alkali-borate glasses with copper additions were the subject of the investigation. An attempt was made to trace the characteristics of copper surroundings and also to find out the possibility for chlorine to enter the first coordination sphere of paramagnetic ion. Substitution of Na2O for B2O3 was done changing the Na2O/B2O3 ratio from 1:3 to 1:19. Concentration of copper was constant and equal to 0.14 mass.%. Copper and chlorine were added to glass above the 100% of the main glass composition. The nature of the chemical bond Cu(2)-anion was studied by EPR method. It was established that the degree of covalence bond Cu-O increased with equimolecular substitution of glass-forming oxides in P2O5-B2O3-SiO2-GeO2 series and with increasing concentration of sodium oxide in alkali-borate glasses. Additions of chlorine to the glass lead to the formation mixed chlorine-oxygen complexes of copper. The probability of chlorine entry into the first coordination sphere of copper depends on the sodium oxide concentration in glass and increases with the decrease of the last

  16. Chemical nature of phytic acid conversion coating on AZ61 magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Pan Fusheng [College of Materials Science and Engineering, Chongqing University, Chongqing, 400044 (China); Yang Xu, E-mail: yangxu2524@yahoo.com.cn [College of Materials Science and Engineering, Chongqing University, Chongqing, 400044 (China); Chemistry Department, Third Military Medical University, Chongqing, 400038 (China); Zhang Dingfei [College of Materials Science and Engineering, Chongqing University, Chongqing, 400044 (China)

    2009-07-30

    Phytic acid (PA) conversion coating on AZ61 magnesium alloy was prepared by the method of deposition. The influences of pH, time and PA concentration on the formation process, microstructure and properties of the conversion coating were investigated. Scanning electron microscopy (SEM) was used to observe the microstructure. The chemical nature of conversion coating was investigated by energy dispersive X-ray spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR) techniques. The corrosion resistance was examined by means of potentiodynamic polarization method. The adhesive ability was tested by score experiments. The results showed that the growth and microstructure of the conversion coatings were all obviously affected by pH, time and PA concentration. In 0.5 mg/ml PA solution with a pH of 5, an optimization conversion coating formed after 20 min immersion time by deposition of PA on AZ61 magnesium alloy surface through chelating with Al{sup 3+}. It made the corrosion potential E{sub corr} of sample shifted positively about 171 mV than that of the untreated sample, and the adhesive ability reached to Grade 1 (in accordance with GB/T 9286).

  17. Chemical nature of phytic acid conversion coating on AZ61 magnesium alloy

    International Nuclear Information System (INIS)

    Phytic acid (PA) conversion coating on AZ61 magnesium alloy was prepared by the method of deposition. The influences of pH, time and PA concentration on the formation process, microstructure and properties of the conversion coating were investigated. Scanning electron microscopy (SEM) was used to observe the microstructure. The chemical nature of conversion coating was investigated by energy dispersive X-ray spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR) techniques. The corrosion resistance was examined by means of potentiodynamic polarization method. The adhesive ability was tested by score experiments. The results showed that the growth and microstructure of the conversion coatings were all obviously affected by pH, time and PA concentration. In 0.5 mg/ml PA solution with a pH of 5, an optimization conversion coating formed after 20 min immersion time by deposition of PA on AZ61 magnesium alloy surface through chelating with Al3+. It made the corrosion potential Ecorr of sample shifted positively about 171 mV than that of the untreated sample, and the adhesive ability reached to Grade 1 (in accordance with GB/T 9286).

  18. Chemical nature of phytic acid conversion coating on AZ61 magnesium alloy

    Science.gov (United States)

    Pan, Fusheng; Yang, Xu; Zhang, Dingfei

    2009-07-01

    Phytic acid (PA) conversion coating on AZ61 magnesium alloy was prepared by the method of deposition. The influences of pH, time and PA concentration on the formation process, microstructure and properties of the conversion coating were investigated. Scanning electron microscopy (SEM) was used to observe the microstructure. The chemical nature of conversion coating was investigated by energy dispersive X-ray spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR) techniques. The corrosion resistance was examined by means of potentiodynamic polarization method. The adhesive ability was tested by score experiments. The results showed that the growth and microstructure of the conversion coatings were all obviously affected by pH, time and PA concentration. In 0.5 mg/ml PA solution with a pH of 5, an optimization conversion coating formed after 20 min immersion time by deposition of PA on AZ61 magnesium alloy surface through chelating with Al 3+. It made the corrosion potential Ecorr of sample shifted positively about 171 mV than that of the untreated sample, and the adhesive ability reached to Grade 1 (in accordance with GB/T 9286).

  19. 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

  20. Surgical technique: hemi-extensor carpi radialis brevis tenodesis for stabilizing the midcarpal joint in Ehlers-Danlos syndrome.

    Science.gov (United States)

    Krijgh, David D; Harley, Oliver J; Hovius, Steven E; Coert, J Henk; Walbeehm, Erik T

    2014-10-01

    Patients with the hypermobility type of Ehlers-Danlos (EDS-HT) often complain of wrist pain, usually originating from subluxations. As a result of the laxity, wrist function in these patients can be highly limited. This paper presents a surgical technique that stabilizes the lunocapitate joint with the use of an extensor carpi radialis brevis strip. Five patients with confirmed EDS-HT were treated with an extensor carpi radialis brevis tenodesis for their midcarpal instability. Two patients presented with complications following surgery, one major and one minor. This paper presents a potentially satisfactory surgical solution to recurrent midcarpal instability in EDS-HT patients and demonstrates that the use of an autologous tendon might be feasible in spite of a background of abnormal collagen metabolism. PMID:25194773

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

    DEFF Research Database (Denmark)

    Zhao, Yu; Knøchel, Susanne; Siegumfeldt, Henrik

    2014-01-01

    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...... resistance was observed between and within the tested Lactobacillus brevis strains. The results suggest that aerobic cultivation increased the oxidative stress tolerance in Lactobacillus brevis. The results also show that dead cells are randomly distributed in a microcolony and the majority of non...... 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 de Man Rogosa Sharpe (MRS...

  2. 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...... fermentum (34 isolates), Lactobacillus plantarum (10) and Lactobacillus brevis (7). Based on being either highly tolerant to bile, showing an ability for auto-aggregation and/or hydrophobic properties, one L. fermentum (CH58), three L. plantarum (CH3, CH41 and SAU96) and two L. brevis (SAU105 and FFC199...... 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

  3. Origin of the conformational modulation of the 13C NMR chemical shift of methoxy groups in aromatic natural compounds.

    Science.gov (United States)

    Toušek, Jaromír; Straka, Michal; Sklenář, Vladimír; Marek, Radek

    2013-01-24

    The interpretation of nuclear magnetic resonance (NMR) parameters is essential to understanding experimental observations at the molecular and supramolecular levels and to designing new and more efficient molecular probes. In many aromatic natural compounds, unusual (13)C NMR chemical shifts have been reported for out-of-plane methoxy groups bonded to the aromatic ring (~62 ppm as compared to the typical value of ~56 ppm for an aromatic methoxy group). Here, we analyzed this phenomenon for a series of aromatic natural compounds using Density Functional Theory (DFT) calculations. First, we checked the methodology used to optimize the structure and calculate the NMR chemical shifts in aromatic compounds. The conformational effects of the methoxy group on the (13)C NMR chemical shift then were interpreted by the Natural Bond Orbital (NBO) and Natural Chemical Shift (NCS) approaches, and by excitation analysis of the chemical shifts, breaking down the total nuclear shielding tensor into the contributions from the different occupied orbitals and their magnetic interactions with virtual orbitals. We discovered that the atypical (13)C NMR chemical shifts observed are not directly related to a different conjugation of the lone pair of electrons of the methoxy oxygen with the aromatic ring, as has been suggested. Our analysis indicates that rotation of the methoxy group induces changes in the virtual molecular orbital space, which, in turn, correlate with the predominant part of the contribution of the paramagnetic deshielding connected with the magnetic interactions of the BD(CMet-H)→BD*(CMet-OMet) orbitals, resulting in the experimentally observed deshielding of the (13)C NMR resonance of the out-of-plane methoxy group.

  4. Sulphur isotopic and chemical compositions of the natural waters in the Chuncheon area, Korea

    International Nuclear Information System (INIS)

    The contribution of Chinese sources to the acid deposition in neighbouring countries in Far East Asia has been disputed. This study is to examine the isotopic composition of the S in the natural waters in the Chuncheon area to see if the isotopic composition can be an indicator of the pollution sources in the area. Meteoric water sampled between September 2000 and July 2001 and surface water sampled in December 2000 and April 2001 in the area were collected to examine their chemical and isotopic compositions. The pH values of the meteoric water lie between 4.02 and 6.89, but mostly lower than 5.6, indicating considerable acid deposition. The pH of the surface water is generally higher than that of the atmospheric water. Factor analysis on the concentrations of the dissolved components suggests that the surface water chemistry depends principally on the chemistry of the atmospheric water. The dissolution of carbonate minerals and silicate-water interaction plays a rather minor role in affecting the water chemistry. δ18O and δD of all the natural water samples align fairly well along the global meteoric water line. The δ34S of the dissolved SO4 in the meteoric water has values ranging from 3.4 to 8.2 per mille, showing little seasonal difference. The contribution from sea-salt to the total atmospheric S is estimated to be less than 10%. The δ34S of the anthropogenic S in the Chuncheon atmosphere is calculated to be 2.5 to 7.2 per mille, which partly overlaps the reported values of S in Chinese coal, Chinese rainfall, and Japanese fallout. Appropriate tracking and quantitative estimation of the contribution from possible pollution sources to the local S concentrations requires more information on the isotopic compositions of the potential pollution sources. The δ34S of the dissolved SO4 in the surface water has values ranging from 3.2 to 6.2 per mille, which is a little narrower than that of the meteoric water. The δ34S and the concentration range of the

  5. 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

  6. Brevenal, a brevetoxin antagonist from Karenia brevis, binds to a previously unreported site on mammalian sodium channels.

    Science.gov (United States)

    Gold, Elena P; Jacocks, Henry M; Bourdelais, Andrea J; Baden, Daniel G

    2013-06-01

    Brevetoxins are a family of ladder-frame polyether toxins produced by the marine dinoflagellate Karenia brevis. During blooms of K. brevis, inhalation of brevetoxins aerosolized by wind and wave action can lead to asthma-like symptoms in persons at the beach. Consumption of either shellfish or finfish contaminated by K. brevis blooms can lead to the development of neurotoxic shellfish poisoning. The toxic effects of brevetoxins are due to binding at a defined site on, and subsequent activation of, voltage-sensitive sodium channels (VSSCs) in cell membranes (site 5). In addition to brevetoxins, K. brevis produces several other ladder-frame compounds. One of these compounds, brevenal, has been shown to antagonize the effects of brevetoxin. In an effort to further characterize to effects of brevenal, a radioactive analog ([(3)H]-brevenol) was produced by reducing the side-chain terminal aldehyde moiety of brevenal to an alcohol using tritiated sodium borohydride. A KD of 67 nM and Bmax of 7.1 pmol/mg protein were obtained for [(3)H]-brevenol in rat brain synaptosomes, suggesting a 1:1 matching with VSSCs. Brevenal and brevenol competed for [(3)H]-brevenol binding with Ki values of 75 nM and 56 nM, respectively. However, although both brevenal and brevenol can inhibit brevetoxin binding, brevetoxin was completely ineffective at competition for [(3)H]-brevenol binding. After examining other site-specific compounds, it was determined that [(3)H]-brevenol binds to a site that is distinct from the other known sites including the brevetoxin site (site 5) although some interaction with site 5 is apparent. PMID:23789024

  7. Serological Correlate of Protection in Guinea Pigs for a Recombinant Protective Antigen Anthrax Vaccine Produced from Bacillus brevis

    OpenAIRE

    Chun, Jeong-Hoon; Choi, On-Jee; Cho, Min-Hee; Hong, Kee-Jong; Seong, Won Keun; Oh, Hee-Bok; Rhie, Gi-eun

    2012-01-01

    Objective Recombinant protective antigen (rPA) is the active pharmaceutical ingredient of a second generation anthrax vaccine undergoing clinical trials both in Korea and the USA. By using the rPA produced from Bacillus brevis pNU212 expression system, correlations of serological immune response to anthrax protection efficacy were analyzed in a guinea pig model. Methods Serological responses of rPA anthrax vaccine were investigated in guinea pigs that were given single or two injections (inte...

  8. 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.

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

    Science.gov (United States)

    Jääskeläinen, Pentti; Engelhardt, Peter; Hynönen, Ulla; Torkkeli, Mika; Palva, Airi; Serimaa, Ritva

    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 Å and 435 Å.

  10. The oligolectic bee Osmia brevis sonicates Penstemon flowers for pollen: a newly documented behavior for the Megachilidae

    OpenAIRE

    Cane, James

    2014-01-01

    Flowers with poricidally dehiscent anthers are typically nectarless but are avidly visited and often solely pollinated by bees that sonicate the flowers to harvest pollen. Sonication results from shivering the thoracic flight muscles. Honey bees (Apis) and the 4,000+ species of Megachilidae are enigmatic in their seeming inability to sonicate flowers. The oligolectic megachilid bee Osmia brevis was found audibly sonicating two of its beardtongue pollen hosts, Penstemon radicosus and P. cyanan...

  11. Physical-Chemical Factors Affecting the Low Quality of Natural Water in the Khibiny Massif

    Science.gov (United States)

    Mazukhina, Svetlana; Masloboev, Vladimir; Chudnenko, Konstantin; Maksimova, Viktoriia; Belkina, Natalia

    2014-05-01

    One peculiarity of the Khibiny Massif is its spatial location. Rising over 1000 m above the surrounding hilly land and thus obstructing the passage of air masses, it promotes condensation and accumulation of surface and underground water. Annual precipitation here amounts to 600-700 mm in the valleys and up to 1600 mm on mountainous plateaus. Using this water for drinking and household purposes is problematic due to excess Al and F concentrations and high pH values. Now it is known that in its profile, the Massif is represented by three hydrogeological subzones: the upper (aerated), medium and lower ones. The upper subzone spreads throughout the Massif and is affected by the local drainage network and climatic conditions. The medium subzone is permanently saturated with underground water flowing horizontally to sites of discharge at the level of local river valleys and lakes. The fissure-vein water in the lower subzone is confined to tectonic fractures and faults in the so far underexplored, deeper parts of the Massif. Being abundant, this water ascends under high pressure. At places, water has been observed spurting from as deep as 700 m, and even 960 m. In the latter case, the temperature of ascending water was higher than 18 centigrade (Hydrogeology of the USSR, V. 27, 1971). This work was undertaken to reveal the nature of the low quality of water in the Khibiny by using physical-chemical modeling (software package Selector, Chudnenko, 2010). Processes of surface and underground water formation in the Khibiny were examined within a physical-chemical model (PCM) of the "water-rock-atmosphere-hydrogen" system. In a multi-vessel model used, each vessel represented a geochemical level of the process interpreted as spatiotemporal data - ξ (Karpov, 1981). The flow reactor consisted of 4 tanks. In the first tank, water of the Kuniok River (1000 L) interacted with atmosphere and an organic substance. The resulting solution proceeded to tanks 2-4 containing with

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

    International Nuclear Information System (INIS)

    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.

  13. 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. PMID:24062062

  14. 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

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

    Directory of Open Access Journals (Sweden)

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

    2014-01-01

    Full Text Available 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 production of silage is considered safe for livestock species, for consumers of products from animals fed the treated silage and for the environment. The additive should be regarded as a skin and eye irritant and a potential skin and respiratory sensitiser and should be treated accordingly. The FEEDAP Panel concluded that L. brevis has the potential to increase aerobic stability of the treated silage at the minimum recommended dose of 1.0 × 108 CFU/kg fresh material. This was demonstrated in forage materials with a dry matter content of 29–46 %.

  16. Variation in Chemical Defense Among Natural Populations of Common Toad, Bufo bufo, Tadpoles: the Role of Environmental Factors.

    Science.gov (United States)

    Bókony, Veronika; Móricz, Ágnes M; Tóth, Zsófia; Gál, Zoltán; Kurali, Anikó; Mikó, Zsanett; Pásztor, Katalin; Szederkényi, Márk; Tóth, Zoltán; Ujszegi, János; Üveges, Bálint; Krüzselyi, Dániel; Capon, Robert J; Hoi, Herbert; Hettyey, Attila

    2016-04-01

    Defensive toxins are widespread in nature, yet we know little about how various environmental factors shape the evolution of chemical defense, especially in vertebrates. In this study we investigated the natural variation in the amount and composition of bufadienolide toxins, and the relative importance of ecological factors in predicting that variation, in larvae of the common toad, Bufo bufo, an amphibian that produces toxins de novo. We found that tadpoles' toxin content varied markedly among populations, and the number of compounds per tadpole also differed between two geographical regions. The most consistent predictor of toxicity was the strength of competition, indicating that tadpoles produced more compounds and larger amounts of toxins when coexisting with more competitors. Additionally, tadpoles tended to contain larger concentrations of bufadienolides in ponds that were less prone to desiccation, suggesting that the costs of toxin production can only be afforded by tadpoles that do not need to drastically speed up their development. Interestingly, this trade-off was not alleviated by higher food abundance, as periphyton biomass had negligible effect on chemical defense. Even more surprisingly, we found no evidence that higher predation risk enhances chemical defenses, suggesting that low predictability of predation risk and high mortality cost of low toxicity might select for constitutive expression of chemical defense irrespective of the actual level of predation risk. Our findings highlight that the variation in chemical defense may be influenced by environmental heterogeneity in both the need for, and constraints on, toxicity as predicted by optimal defense theory. PMID:27059330

  17. 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

    2016-04-01

    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.

  18. 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

    2016-01-01

    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. PMID:27118640

  19. Poly(ADP-ribose)--a unique natural polymer structural features, biological role and approaches to the chemical synthesis.

    Science.gov (United States)

    Drenichev, Mikhail S; Mikhailov, Sergey N

    2015-01-01

    Poly(ADP-ribose) (PAR) is a natural polymer, taking part in numerous important cellular processes. Several enzymes are involved in biosynthesis and degradation of PAR. One of them, poly(ADP-ribose)polymerase-1 (PARP-1) is considered to be a perspective target for the design of new drugs, affecting PAR metabolism. The structure of PAR was established by enzymatic hydrolysis and further analysis of the products, but total chemical synthesis of PAR hasn't been described yet. Several approaches have been developed on the way to chemical synthesis of this unique biopolymer.

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

    International Nuclear Information System (INIS)

    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

  1. Extensor Pollicis Brevis tendon damage presenting as de Quervain’s disease following kettlebell training

    Science.gov (United States)

    2013-01-01

    Kettlebell exercises are more efficient for an athlete to increase his or her muscle strength. However it carries the risk of injury especially in the beginners. A 39 year old gentleman came to our clinic with radial sided wrist pain following kettlebell exercises. Clinically patient had swelling and tenderness over the tendons in the first dorsal wrist compartment, besides Finklesten test was positive. Patient had a decreased excursion of the thumb when compared to the opposite side. Ultrasound/MRI scan revealed asymmetric thickening of the 1st compartment extensors extending from the base of the thumb to the wrist joint. Besides injury to the Extensor Pollicis Brevis (EPB) tendon by repetitive impact from kettlebell, leading to its split was identified. Detailed history showed that the injury might be due to off-centre handle holding during triceps strengthening exercises. Our report stresses the fact that kettlebell users should be taught about problems of off-center handle holding to avoid wrist injuries. Also, in Kettlebell users with De Quervains disease clinical and radiological evaluation should be done before steroid injection as this might lead to complete tendon rupture. PMID:23731737

  2. Extensor Pollicis Brevis tendon damage presenting as de Quervain's disease following kettlebell training.

    Science.gov (United States)

    Karthik, Karuppaiah; Carter-Esdale, Charles William; Vijayanathan, Sanjay; Kochhar, Tony

    2013-01-01

    Kettlebell exercises are more efficient for an athlete to increase his or her muscle strength. However it carries the risk of injury especially in the beginners. A 39 year old gentleman came to our clinic with radial sided wrist pain following kettlebell exercises. Clinically patient had swelling and tenderness over the tendons in the first dorsal wrist compartment, besides Finklesten test was positive. Patient had a decreased excursion of the thumb when compared to the opposite side. Ultrasound/MRI scan revealed asymmetric thickening of the 1st compartment extensors extending from the base of the thumb to the wrist joint. Besides injury to the Extensor Pollicis Brevis (EPB) tendon by repetitive impact from kettlebell, leading to its split was identified. Detailed history showed that the injury might be due to off-centre handle holding during triceps strengthening exercises. Our report stresses the fact that kettlebell users should be taught about problems of off-center handle holding to avoid wrist injuries. Also, in Kettlebell users with De Quervains disease clinical and radiological evaluation should be done before steroid injection as this might lead to complete tendon rupture. PMID:23731737

  3. Efficient production of artificially designed gelatins with a Bacillus brevis system.

    Science.gov (United States)

    Kajino, T; Takahashi, H; Hirai, M; Yamada, Y

    2000-01-01

    Artificially designed gelatins comprising tandemly repeated 30-amino-acid peptide units derived from human alphaI collagen were successfully produced with a Bacillus brevis system. The DNA encoding the peptide unit was synthesized by taking into consideration the codon usage of the host cells, but no clones having a tandemly repeated gene were obtained through the above-mentioned strategy. Minirepeat genes could be selected in vivo from a mixture of every possible sequence encoding an artificial gelatin by randomly ligating the mixed sequence unit and transforming it into Escherichia coli. Larger repeat genes constructed by connecting minirepeat genes obtained by in vivo selection were also stable in the expression host cells. Gelatins derived from the eight-unit and six-unit repeat genes were extracellularly produced at the level of 0.5 g/liter and easily purified by ammonium sulfate fractionation and anion-exchange chromatography. The purified artificial gelatins had the predicted N-terminal sequences and amino acid compositions and a solgel property similar to that of the native gelatin. These results suggest that the selection of a repeat unit sequence stable in an expression host is a shortcut for the efficient production of repetitive proteins and that it can conveniently be achieved by the in vivo selection method. This study revealed the possible industrial application of artificially designed repetitive proteins. PMID:10618240

  4. Steric vs. electronic effects in the Lactobacillus brevis ADH-catalyzed bioreduction of ketones.

    Science.gov (United States)

    Rodríguez, Cristina; Borzęcka, Wioleta; Sattler, Johann H; Kroutil, Wolfgang; Lavandera, Iván; Gotor, Vicente

    2014-01-28

    Lactobacillus brevis ADH (LBADH) is an alcohol dehydrogenase that is commonly employed to reduce alkyl or aryl ketones usually bearing a methyl, an ethyl or a chloromethyl as a small ketone substituent to the corresponding (R)-alcohols. Herein we have tested a series of 24 acetophenone derivatives differing in their size and electronic properties for their reduction employing LBADH. After plotting the relative activity against the measured substrate volumes we observed that apart from the substrate size other effects must be responsible for the activity obtained. Compared to acetophenone (100% relative activity), other small substrates such as propiophenone, α,α,α-trifluoroacetophenone, α-hydroxyacetophenone, and benzoylacetonitrile had relative activities lower than 30%, while medium-sized ketones such as α-bromo-, α,α-dichloro-, and α,α-dibromoacetophenone presented relative activities between 70% and 550%. Moreover, the comparison between the enzymatic activity and the obtained final conversions using an excess or just 2.5 equiv. of the hydrogen donor 2-propanol, denoted again deviations between them. These data supported that these hydrogen transfer (HT) transformations are mainly thermodynamically controlled. For instance, bulky α-halogenated derivatives could be quantitatively reduced by LBADH even employing 2.5 equiv. of 2-propanol independently of their kinetic values. Finally, we found good correlations between the IR absorption band of the carbonyl groups and the degrees of conversion obtained in these HT processes, making this simple method a convenient tool to predict the success of these transformations.

  5. Enhancing the Activity of Glutamate Decarboxylase from Lactobacillus brevis by Directed Evolution☆

    Institute of Scientific and Technical Information of China (English)

    Ling Lin; Sheng Hu; Kai Yu; Jun Huang; Shanjing Yao; Yinlin Lei; Guixiang Hu; Lehe Mei

    2014-01-01

    Glutamate decarboxylase (GAD, EC4.1.1.15) can catalyze the decarboxylation of L-glutamate to form γ-aminobutyrate (GABA), which is in great demand in some foods and pharmaceuticals. In our previous study, gad, the gene coding glutamate decarboxylase from Lactobacil us brevis CGMCC 1306, was cloned and its soluble expression was realized. In this study, error-prone PCR was conducted to improve its activity, followed by a screening. Mutant Q51H with high activity [55.4 mmol·L−1·min−1·(mg protein)−1, 120%higher than that of the wild type at pH 4.8] was screened out from the mutant library. In order to investigate the potential role of this site in the regulation of enzymatic activity, site-directed saturation mutagenesis at site 51 was carried out, and three specific mutants, N-terminal truncated GAD, Q51P, and Q51L, were identified. The kinetic parameters of the three mutants and Q51H were characterized. The results reveal that aspartic acid at site 88 and N-terminal domain are essential to the activity as well as correct folding of GAD. This study not only improves the activity of GAD, but also sheds new light on the structure–function relationship of GAD.

  6. 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

  7. Direct chemical characterization of natural wood resins by temperature-resolved and space-resolved Fourier transform infrared spectroscopy

    Science.gov (United States)

    Chen, Jian-bo; Zhou, Qun; Sun, Su-qin

    2016-07-01

    Wood resins are valuable natural products with wide utilizations. Either in the form of resin exudates or in the form of resin-containing woods, natural wood resins are usually complex mixtures consisting of various compounds. Therefore, effective chemical characterization methods are necessary for the research and quality control of natural wood resins. No need for separation or labeling, wood resin samples can be measured directly by Fourier transform infrared (FT-IR) spectroscopy, which reduces the testing costs and avoids the possible distortions caused by the pretreatments. However, the absorption bands of various compositions in the resin sample are assembled in a single spectrum by the separation-free measurement, which makes it difficult to identify the compounds of interest and decreases the limits of detection. In this research, the temperature-resolved and space-resolved FT-IR techniques are proposed to resolve the overlapped signals for the direct, selective, and sensitive characterization of natural wood resins. For resin exudates, the temperature-resolved FT-IR spectroscopy and two-dimensional correlation analysis can resolve the absorption bands of different compounds according to their responses to the thermal perturbations. For resin-containing woods, the FT-IR microspectroscopic imaging and principal component analysis can resolve the absorption bands of different compounds according to their positions. The study of six kinds of wood resins proves the feasibility of temperature-resolved and space-resolved FT-IR techniques for the direct, selective, and sensitive chemical characterization of natural wood resins.

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

    International Nuclear Information System (INIS)

    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

    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.

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

    International Nuclear Information System (INIS)

    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 (CH3Cl), 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

  11. 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. PMID:24794812

  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. 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.

  14. Effects of the red tide dinoflagellate, Karenia brevis, on early development of the eastern oyster Crassostrea virginica and northern quahog Mercenaria mercenaria.

    Science.gov (United States)

    Rolton, Anne; Vignier, Julien; Soudant, Philippe; Shumway, Sandra E; Bricelj, V Monica; Volety, Aswani K

    2014-10-01

    The brevetoxin-producing dinoflagellate, Karenia brevis, adversely affects many shellfish species including the commercially and ecologically important bivalve molluscs, the northern quahog (=hard clam) Mercenaria mercenaria and eastern oyster Crassostrea virginica, in the Gulf of Mexico, USA. This study assessed the effects of exposure of these bivalves to K. brevis during their early development. In separate experiments, embryos of 2-4 cell stage of M. mercenaria and C. virginica were exposed to both whole and lysed K. brevis cells isolated from Manasota Key, Florida. Low bloom concentrations of 500 to 3000 cells mL(-1) were simulated for 96 h. Shell length, percent abnormality (and normality), and percent mortality of resulting larvae were measured. Percentages were recorded after 6, 24, and 96 h of exposure; larval shell length was measured at 24 and 96 h. For both quahogs and oysters, the effects of exposing embryos to K. brevis on all larval responses were generally dose- and time-dependent. Percent mortalities and abnormalities of both clam and oyster embryos increased significantly after only 6h of exposure to whole cells of K. brevis. For clams, these parameters were significantly higher in whole and lysed treatments (at 3000 cells mL(-1)) than in controls. Percent mortalities of oysters were significantly higher in the whole-cell treatment (3000 cells mL(-1)) than under control conditions. After 24h of exposure, mean larval shell length of both bivalve species was significantly reduced relative to controls. This was evident for clam larvae in both the lysed treatment at 1500 cells mL(-1) and in whole and lysed treatments at 3000 cells mL(-1), and for oyster larvae in the lysed treatment at 3000 cells mL(-1). After 96 h, both species exposed to the lysed cell treatment at 3000 cells mL(-1) had significantly smaller larvae compared to those in the control. Overall, lysed cells of K. brevis had a more pronounced effect on shell length, percent abnormality

  15. A novel power generation system based on moderate conversion of chemical energy of coal and natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Wei Han; Hongguang Jin; Rumou Lin [Chinese Academy of Sciences, Beijing (China). Institute of Engineering Thermophysics

    2011-01-15

    This paper proposes a novel power generation system that implements mutually beneficial use of natural gas and coal. In conventional power plants fossil fuels are usually directly burned with air to convert the chemical energy to thermal energy for power generation. In combustion processes, about 30% of exergy of fuels is destructed, and the decrease in the irreversibility of combustion processes has large potential to improve the performance of power plants. The new system attempts to use chemical exergy of fuels before combustion through coordinated use of coal and natural gas. First approximate 60% of coal is gasified in a gasifier with air and steam as oxidant, then, the unconverted residuals (char) and natural gas are utilized synthetically based on the method of char-fired reforming to generate syngas, in which the combustion of char will drive the methane/steam-reforming reaction. The fuel gas from the partial gasification of coal and syngas from char-fired reforming are mixed together and fed into a combined cycle for power generation. As a result, the overall thermal efficiency of the new system is about 51.5% based on the current turbine technologies and the net thermal efficiency of coal to electricity of the new system can reach near 48.6%. The results obtained here may provide a new way of using coal and natural gas more efficiently and economically. 28 refs., 6 figs., 6 tabs., 1 app.

  16. [Effect of physico-chemical characteristics of activated carbon on the adsorption of organic pollutants in natural water].

    Science.gov (United States)

    Zhang, Jing-Yi; Shi, Bao-You; Xie, Jian-Kun; Yuan, Hong-Lin; Wang, Dong-Sheng

    2011-02-01

    In this paper, the adsorption characteristics of two synthetic organic compounds (SOCs), i. e., methyl parathion(MP) and trichloroethylene (TCE), and natural organic matter (NOM) on powdered activated carbons (PAC) in natural water were studied. On the basis of fully characterizing the physical and chemical characteristics of PAC, the effect of physical and chemical properties of PAC on the adsorption of low molecular weight SOCs in natural water was studied by correlation analysis. The effect of molecular weight fractionation on the adsorption of NOM on PAC was investigated using high performance size exclusion chromatography (HPSEC). It was found that, compared to the surface chemistry, the physical property (pore properties) of PAC was the critical factor to determine its adsorption capacity of MP and TCE in natural water. The adsorption of the low molecular weight SOC and NOM with apparent molecular weight (AMW) < 500 on PAC was primarily impacted by the micropore surface area, and that of NOM with 500 < AMW < 3 000 was affected by the mesopore surface area combined with the mesopore size distribution. PMID:21528573

  17. The Synergic Anti-inflammatory Impact of Gleditsia sinensis Lam. and Lactobacillus brevis KY21 on Intestinal Epithelial Cells in a DSS-induced Colitis Model.

    Science.gov (United States)

    Kim, Younghoon; Koh, Ji Hoon; Ahn, Young Jun; Oh, Sejong; Kim, Sea Hun

    2015-01-01

    We investigated the synergic anti-inflammatory activity of Gleditsia sinensis Lam. (GS) extract and Lactobacillus brevis KY21 both in vitro and in vivo. Western blot analysis and immunostaining showed that AKT phosphorylation that increased by the exposure of LPS were significantly decreased by the presence of either GS extract or L. brevis KY21. In addition, p65 intracellular transport was critically inhibited by GS extract and L. brevis KY21. We further studied these effects using an in vivo dextran sulfate sodium (DSS)-induced mouse model. Body weight, food intake, and clinical scores were dramatically decreased after treatment with DSS, whereas these effects were palliated by the addition of GS extract and L. brevis KY21. Importantly, transcription of genes encoding pro-inflammatory cytokines including IL-1β, TNF-α, and IFN-γ in mesenteric lymph nodes (MLN) and the spleen were increased by DSS treatment, whereas they were inhibited by the presence of GS extract and L. brevis KY21.

  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. Migration of humus substances from soil to water and the main chemical reaction (in different natural zone of Russian Federation)

    Science.gov (United States)

    Dinu, Marina; Moiseenko, Tatiana; Gashkina, Natalia; Kremleva, Tatiana

    2014-05-01

    Migration of humus substances (HS) from soil to natural water has zonal specificity. Soil HS of different natural areas characterized by specific functional features, different molecular weight (MW) distribution and other physicochemical parameters. Due to the specifics of formation, waters in Russia widely distributed colored water with high concentrations of humus substances. HS involved in many chemical reactions in natural waters/soil. The most important: 1.Dissociation, association and same destruction - reactions are particularly important for assessing the acidification of natural waters 2.Complexation with metals - reactions reduce the toxicity of most metals We researched the differences in the qualitative and quantitative composition of soil HS catchment and HS in natural waters of some climatic zones. Samples were taking: the mixing zone forests (sod-podzolic soils) and the steppe zone (black earth) European Territory of Russia (ETR). In order to examine process of migration humus substances from soil to water have been performed HPLC, IR spectrometry and mass spectrometry analyses. We funded change of HS structure and MW in soil/water. The water HS of the mixed forest characterized as same ratio of functional groups as soil catchments. The molecular weight distribution in water - predominate medium (500-1000 kDa), and low molecular weight fractions (soils. In HS catchment soils predominate nitrogen- and sulfur- functional group and in HS water - nitrogen-, oxygen- functional group. The molecular weight of HS in natural waters is macromolecular fractions ( > 1000 kDa). For evaluating of the acidification effect on structures of humic substances in natural waters/soil we used date of survey more than 300 lakes on the European Russia (ETP) and Western Siberia (WS) for assessing chemical parameters. Chemical analyzes of water samples were performed by a single method in accordance with the recommendations ICP-Water report 105/2010, 2010. We researched HS

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

    Science.gov (United States)

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

    2005-06-01

    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 architecture and natural product inspired compound library design. Domains and proteins identified as being structurally similar in their ligand-sensing cores are grouped in a protein structure similarity cluster (PSSC). Natural products can be considered as evolutionary pre-validated ligands for multiple proteins and therefore natural products that are known to interact with one of the PSSC member proteins are selected as guiding structures for compound library synthesis. Application of this novel strategy for compound library design provided enhanced hit rates in small compound libraries for structurally similar proteins.

  1. Polyphosphate, an active molecule derived from probiotic Lactobacillus brevis, improves the fibrosis in murine colitis.

    Science.gov (United States)

    Kashima, Shin; Fujiya, Mikihiro; Konishi, Hiroaki; Ueno, Nobuhiro; Inaba, Yuhei; Moriichi, Kentaro; Tanabe, Hiroki; Ikuta, Katsuya; Ohtake, Takaaki; Kohgo, Yutaka

    2015-08-01

    Inflammatory bowel disease frequently causes intestinal obstruction because of extensive fibrosis. This study investigated whether polyphosphate (poly P), an active molecule derived from Lactobacillus brevis, could improve the fibrosis in a model of chronic colitis. In this study, dextran sodium sulfate (DSS)-induced chronic colitis models and trinitrobenzene sulfonic acid (TNBS)-induced colitis models were used as models of fibrosis. To clarify the mechanism responsible for the observed effects, Caco-2/brush border epithelial (BBE) and naive T helper lymphocyte (THP)-1 cells were treated with lipopolysaccharide (LPS) to induce inflammation. Non-cancer human colon fibroblast (CCD-18) cells were treated with transforming growth factor beta 1 (TGF-β1) to induce fibrosis. The expression levels of fibrosis- and inflammation-associated molecules were evaluated by both a Western blotting analysis and reverse transcriptase-polymerase chain reaction (RT-PCR). The histologic inflammation and fibrosis were significantly improved in the group administered poly P in both the DSS and TNBS colitis models. The levels of interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α) were significantly decreased by poly P treatment. The expression levels of TGF-β1 and collagens in the colitis mice were decreased by poly P. The LPS-induced expressions of IL-1β and TGF-β1 in Caco-2/BBE cells and of TNF-α in THP-1 cells were reduced by poly P treatment. Poly P did not affect the expression of collagens and connective tissue growth factor in the CCD-18 cells. In conclusion, poly P suppresses intestinal inflammation and fibrosis by downregulating the expression of inflammation- and fibrosis-associated molecules in the intestinal epithelium. The administration of poly P is therefore a novel option to treat fibrosis because of chronic intestinal inflammation. PMID:25766132

  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. 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

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

    Science.gov (United States)

    Jaouadi, Nadia Zaraî; Rekik, Hatem; Badis, Abdelmalek; Trabelsi, Sahar; Belhoul, Mouna; Yahiaoui, Amina Benkiar; Ben Aicha, Houda; Toumi, Abdessatar; Bejar, Samir; Jaouadi, Bassem

    2013-01-01

    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 chemicals

  5. 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.

  6. Bone as a Possible Target of Chemical Toxicity of Natural Uranium in Drinking Water

    OpenAIRE

    Kurttio, Päivi; Komulainen, Hannu; Leino, Aila; Salonen, Laina; Auvinen, Anssi; Saha, Heikki

    2004-01-01

    Uranium accumulates in bone, affects bone metabolism in laboratory animals, and when ingested in drinking water increases urinary excretion of calcium and phosphate, important components in the bone structure. However, little is known about bone effects of ingested natural uranium in humans. We studied 146 men and 142 women 26–83 years of age who for an average of 13 years had used drinking water originating from wells drilled in bedrock, in areas with naturally high uranium content. Biochemi...

  7. Survey of marine natural product structure revisions: a synergy of spectroscopy and chemical synthesis

    OpenAIRE

    Suyama, Takashi L.; Gerwick, William H.; McPhail, Kerry L.

    2011-01-01

    The structural assignment of new natural product molecules supports research in a multitude of disciplines that may lead to new therapeutic agents and or new understanding of disease biology. However, reports of numerous structural revisions, even of recently elucidated natural products, inspired the present survey of techniques used in structural misassignments and subsequent revisions in the context of constitutional or configurational errors. Given the comparatively recent development of m...

  8. [The disturbances of the thyroid hormone homeostasis caused by chemical substances occurring in natural environment].

    Science.gov (United States)

    Kiałka, Marta; Doroszewska, Katarzyna; Mrozińska, Sandra; Milewicz, Tomasz; Stochmal, Ewa; Krzysiek, Józef

    2014-01-01

    The thyroid is an endocrine gland synthesizing, storaging and secreting thyroxine (T4) and triiodothyronine (T3). Currently, there are more and more reports and evidences that various chemical contaminants present in the environment, mainly polychlorinated biphenyls, interfere with stages of regulation, synthesis, secretion, transport of thyroid hormones. That can have a significant negative impact on the human body's endocrine homeostasis.

  9. Cerebral Palsy Tendon Transfers: Flexor Carpi Ulnaris to Extensor Carpi Radialis Brevis and Extensor Pollicis Longus Reroutement.

    Science.gov (United States)

    Bansal, Anchal; Wall, Lindley B; Goldfarb, Charles A

    2016-08-01

    The flexor carpi ulnaris to extensor carpi radialis brevis transfer and extensor pollicis longus rerouting combined with thenar release are 2 successful surgical interventions for children with spastic cerebral palsy. The goal of both procedures is to improve quality of life for patients who have previously failed conservative management, and the degree of expected improvement is predicated on several patient variables, making careful patient selection crucial for ensuring successful outcomes. Here, surgical technique is described; risk factors are discussed, and outcomes related to both procedures are presented. PMID:27387086

  10. Morphostructural investigation of the female reproductive system and molecular evidence for Wolbachia in Balclutha brevis Lindberg 1954 (Hemiptera, Cicadellidae).

    Science.gov (United States)

    Pappalardo, A M; D'Urso, V; Viscuso, R; Ferrito, V; Giunta, M C; Cupani, S; Vitale, D G M

    2016-02-01

    Balclutha brevis Lindberg 1954 (Homoptera, Cicadellidae) is an allochthonous species that is rapidly spreading in Sicily and in mainland Europe due to the wide spread of its host plant and therefore could also compete with populations of native species. Considering these ecological implications, based on the lacking ultrastructural data about the reproductive systems of the Auchenorrhyncha and since previous investigations on the male reproductive system of B. brevis have shown some interesting features, we carried out morphostructural investigations on the female reproductive system of this alien leafhopper. Moreover, given the high interest in literature on Wolbachia entomoparasite and based on our previous studies, we provided a contribution to further investigations in applied sciences. For this aim we performed a molecular analysis on males and females of B. brevis to detect the possible presence of strains of the bacterium known to alter host reproductive biology. The female reproductive system has a morphological organization comparable to the general anatomical features of most of the Auchenorrhyncha species; however, comparing our data with the literature, some considerations are discussed. As for the histological and ultrastructural investigations, our results show a secretory activity of the various examined structures. In the spermatheca of B. brevis, in particular, the secretory activity is more marked in the sac-shaped tract, where histochemical investigations showed a lipid component of the secretion; possible origin of this component is discussed. Moreover, mainly free spermatozoa are found in the sac-shaped tract of the spermatheca and in the common oviduct. As for the latter, an interesting findings is the lack of cuticular intima on the epithelial surface of the common oviduct; furthermore, the observed features and the literature in this regards led us to review the significance of the structure called as spermatheca. The molecular screening

  11. Influência do campo eletromagnético no comportamento de cupins de madeira seca (Cryptotermes brevis)

    OpenAIRE

    Giovanella, Rodrigo

    2013-01-01

    Resumo: Este trabalho teve como objetivo determinar a relação e influência do campo eletromagnético sobre o organismo de cupins da espécie Cryptotermes brevis, ordem Isoptera, família Kalotermitidae, tendo como base o funcionamento fisiológico de seus sistemas. Para isto diferentes cupins foram submetidos a um campo eletromagnético máximo sob distintas temperaturas ambientes para avaliar a relação deste campo com o potencial elétrico biológico (teoria envolvida no desenvolvimento da equação d...

  12. Longitudinal splitting to the peroneus brevis tendon. Diagnosis and MRI staging; Syndrome fissuraire du tendon court fibulaire

    Energy Technology Data Exchange (ETDEWEB)

    Tavernier, T. [Clinique de la Sauvegarde, 69 - Lyon (France); Bonnin, M. [Clinique Charcot, 69 - Sainte-Foy-les-Lyon (France); Bouysset, M. [Centre hospitalier Lyon-Sud, 69 Pierre-Benite (France)

    1997-05-01

    We present a series of 38 cases of longitudinal splitting of the peroneus brevis tendon revealed by MR imaging (12 lesions were confirmed at surgery). MRI enabled classification in four surgical grades.The frequency of such lesions in chronic ankle instability as observed in our series is often reported in the literature. Bilateral cases are common. Asymptomatic cases do occur, especially in grades I and II. MRI has been shown to be a very effective investigation for demonstrating this tendinous lesion: the proton density weighted sequence in the axial plane is the most adequate sequence. (authors). 15 refs.

  13. 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

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

    Science.gov (United States)

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

    2012-05-15

    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

  15. Synergistic effect of ionizing radiation on chemical disinfectant treatments for reduction of natural microflora on seafood

    Science.gov (United States)

    Kim, Hyunjoo; Ha, Ji-Hyoung; Lee, Ju-Woon; Jo, Cheorun; Ha, Sang-Do

    2012-08-01

    The purpose of this study was to determine whether combined treatments would produce synergistic disinfection effects on seafood products such as mussel and squid compared with single treatments. We investigated the bactericidal effects of chlorine and ionizing radiation on the natural microflora of mussel and squid. Total aerobic bacteria initially ranged from 102 to 104 Log CFU/g. More than 100 ppm of chlorine and irradiation at 1 kGy were sufficient to reduce the total aerobic bacteria on mussel and squid to a level lower than detection limit (10 CFU/g). Synergistic effects against natural microflora were observed for all combined treatment. These results suggest that a significant synergistic benefit results from combine chlorine-ionizing radiation treatment against natural microflora on mussel and squid.

  16. Morphological and chemical nature of fiber strands of oil palm empty-fruit-bunch (OPEFB)

    OpenAIRE

    Wan Rosli Wan Daud; Kwei-Nam Law; Arniza Ghazali,

    2007-01-01

    In this work we examined the morphological and chemical characteristics of the fibrous strands of oil palm empty-fruit-bunch which were left behind after being stripped of their fruits used for oil production. The empty-fruit-bunches were mechanically loosened to yield the fibrous strands, which can be used in paper and board making. We found that the fibrous strands had unique structure by having several large-diameter, long vessel elements in their core region, surrounded by vascular fibers...

  17. Improving postharvest vase-life and quality of cut gerbera flowers using natural and chemical preservatives

    OpenAIRE

    Mehrdad Jafarpour; Ahmad Golparvar; Omid Askari-Khorasgani; Shima Amini

    2015-01-01

    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 comprise...

  18. A new way for chemical degradation of plastic by natural volatile constituents of Ledum palustre

    Institute of Scientific and Technical Information of China (English)

    XIU Zhilong; ZHU Xiuling; ZHANG Daijia; YIN Jianzhong; WANG Dehe; AN Lijia

    2003-01-01

    A novel phenomenon of degradation of polypropylene plastic by volatile constituents of Ledum palustre is reported in this study. The characteristic of degradation is described by tensile strength, melting point, and scanning electron micrographs as well as optical micrographs. The chemical composition of volatile oil of Ledum palustre is analyzed by gas chrography and mass spectrometry. The mechanism of degradation and problems needed to be solved are also discussed.

  19. Chemical constituents of peppers (Piper spp.) and application to food preservation: naturally occurring antioxidative compounds.

    Science.gov (United States)

    Nakatani, N; Inatani, R; Ohta, H; Nishioka, A

    1986-08-01

    In a structure analysis of the compounds of the genus Piper (Family Piperaceae), we identified five phenolic amides from Piper nigrum, seven compounds from P. retrofractum, and two compounds from P. baccatum. All the phenolic amides possess significant antioxidant activities that are more effective than the naturally occurring antioxidant, alpha-tocopherol. One amide, feruperine, has antioxidant activity as high as the synthetic antioxidants, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). Naturally occurring antioxidants, therefore, may surpass BHA and BHT in their ability to inactivate mutagens in food. PMID:3757949

  20. 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 (Prats. Diabetes induced by STZ injection decreased body weight (Pglucose was increased (Pglucose levels was observed in diabetic rats receiving L. brevis DPC 6108, compared with diabetic-controls. Both the composition and diversity of the intestinal microbiota were affected by diabetes. Microbial diversity in diabetic rats supplemented with low GABA was not reduced (P>0.05), 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. PMID:27013462

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

    International Nuclear Information System (INIS)

    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)

  2. Synergistic effect of ionizing radiation on chemical disinfectant treatments for reduction of natural microflora on seafood

    International Nuclear Information System (INIS)

    The purpose of this study was to determine whether combined treatments would produce synergistic disinfection effects on seafood products such as mussel and squid compared with single treatments. We investigated the bactericidal effects of chlorine and ionizing radiation on the natural microflora of mussel and squid. Total aerobic bacteria initially ranged from 102 to 104 Log CFU/g. More than 100 ppm of chlorine and irradiation at 1 kGy were sufficient to reduce the total aerobic bacteria on mussel and squid to a level lower than detection limit (10 CFU/g). Synergistic effects against natural microflora were observed for all combined treatment. These results suggest that a significant synergistic benefit results from combine chlorine-ionizing radiation treatment against natural microflora on mussel and squid. - Highlights: ► Synergistic effect of combined treatments of chlorine and irradiation was tested using seafood. ► Synergistic effect against natural microflora was observed for all combined treatments. ► Therefore, it is recommended that industry use the combined treatment for better effect.

  3. Spectroscopic and quantum chemical analysis of a natural product - Hayatin hydrochloride

    Science.gov (United States)

    Mishra, Rashmi; Srivastava, Anubha; Tandon, Poonam; Jain, Sudha

    2015-08-01

    Majority of drugs in use today are natural products, natural product mimics or semi synthetic derivatives. Therefore in recent times, focus on plant research has increased all over the world and large body of evidence has been collected to show immense potential of medicinal plants used in various traditional systems. Therefore, in the present communication to aid that research, structural and spectroscopic analysis of a natural product, an alkaloid Hayatin hydrochloride was performed. Both ab initio Hartree-Fock and density functional theory employing B3LYP with complete relaxation in the potential energy surface using 6-311G (d,p) basis set were used for the calculations. The vibrational frequencies were calculated and scaled values were compared with experimental FT-IR and micro-Raman spectra. The complete assignments were performed on the basis of potential energy distribution. The structure-activity relationship has also been interpreted by mapping electrostatic potential surface, which are valuable information for the quality control of medicines and drug-receptor interactions. Electronic properties have been analysed employing TD-DFT for both gaseous and solvent phase. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analyzed using natural bond orbital (NBO) analysis.

  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.

  5. Chemical composition of natural waters of contaminated area: The case for the Imandra Lake catchment (the Kola Peninsula)

    Science.gov (United States)

    Evtyugina, Z. A.; Guseva, N. V.; Kopylova, J. G.; A, Vorobeva D.

    2016-03-01

    The study of the current chemical composition of natural waters in the eastern and western parts of the Imandra Lake catchment was performed using ion chromatography, potentiometry and inductively coupled plasma mass spectrometry. It was found that the content of trace elements in the surface water is considerably higher than that in the groundwater. The nickel and copper concentrations exceed the background levels over 19 and 2 times respectively in groundwater, and 175 and 61 times in the surface waters. These data show that the Severonikel influences negatively air and surface water.

  6. Marked influence of the nature of the chemical bond on CP-violating signature in molecular ions HBr+ and HI+

    International Nuclear Information System (INIS)

    Heavy polar molecules offer a great sensitivity to the electron electric dipole moment (EDM). To guide emerging searches for EDMs with molecular ions, we estimate the EDM-induced energy corrections for hydrogen halide ions HBr+ and HI+ in their respective ground X 2Π3/2 states. We find that the energy corrections due to EDM for the two ions differ by an unexpectedly large factor of 15. We demonstrate that a major part of this enhancement is due to a dissimilarity in the nature of the chemical bond for the two ions: the bond that is nearly of ionic character in HBr+ exhibits predominantly a covalent nature in HI+. We conclude that because of this enhancement the HI+ ion may be a potentially competitive candidate for the EDM search

  7. Nature

    OpenAIRE

    Ferretti, Federico; Schmidt Di Friedberg, Marcella

    2012-01-01

    International audience From the ancient times to the present debates on nature and environment, the idea of Nature has been one of the main concepts which interested Geographers. This paper deals with the representations of this idea in the works of thinkers who played a major role in shaping modern Geography, with a special focus on the Mediterranean world. It aims to clarify how Nature was important in defining heuristic strategies of the geographical sciences and their explications of r...

  8. 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.

  9. Probing the nature of phases across the phase transition at finite isospin chemical potential

    CERN Document Server

    Bali, Gunnar S; Gavai, Rajiv V; Mathur, N

    2016-01-01

    We compare the low eigenvalue spectra of the Overlap Dirac operator on two sets of configurations at $\\mu_I/\\mu_I^c$ = 0.5 and 1.5 generated with dynamical staggered fermions at these isospin chemical potential on $24^3 \\times 6$ lattices. We find very small changes in the number of zero modes and low lying modes which is in stark contrast with those across the corresponding finite temperature phases where one sees a drop across the phase transition. Possible consequences are discussed.

  10. Application of density functional theory (DFT) to study the properties and degradation of natural estrogen hormones with chemical oxidizers

    Energy Technology Data Exchange (ETDEWEB)

    Rokhina, Ekaterina V.; Suri, Rominder P.S., E-mail: rominder.suri@temple.edu

    2012-02-15

    Estrone (E1), 17{beta}-estradiol (E2), estriol (E3), equilin (EQ) and 17{alpha}-estradiol (17{alpha}) estrogen hormones are released by humans and animals and have been detected in the environment and municipal wastewater treatment plants. The structural and electronic properties of natural hormone molecules are investigated by performing density functional theory calculations and used to predict their properties and chemical behavior. Quantitative structure property relationship (QSPR) approach is applied to correlate the estrogenicity associated with the natural estrogen hormones according to their molecular properties. The obtained relationship reveals the importance of the frontier molecular orbital energy in the interpretation of estrogenic activity of hormones, which is consistent with the previous research. Moreover, the obtained molecular descriptors also aid determination of the degradability of hormones, and to rationalize degradation pathways, with chemical oxidizers such as ozone and hydroxyl radical. Both types of interactions belong to the orbital-controlled reactions. The active sites determined by Fukui functions for the estrogen hormone molecules confirm the reaction pattern that initiates the attack of the aromatic ring for both ozone and hydroxyl radical. The reactive sites of the molecules are mapped with subsequent reaction intermediates and compared with experimental data obtained from the literature. - Highlights: Black-Right-Pointing-Pointer DFT methods described in this paper are suitable for predicting the degradation behavior of natural estrogen hormones. Black-Right-Pointing-Pointer Using QSAR, the estrogenicity of natural hormones was determined by DFT descriptors. Black-Right-Pointing-Pointer The sites of primary ozone and hydroxyl radical attack were predicted using DFT, and findings confirmed by experimental data.

  11. Epoxidized natural rubber toughened aqueous resole type liquefied EFB resin: Physical and chemical characterization

    Science.gov (United States)

    Amran, Umar Adli; Zakaria, Sarani; Chia, Chin Hua

    2013-11-01

    A preliminary study on the reaction between aqueous resole type resinified liquefied palm oil empty fruit bunches fibres (RLEFB) with epoxidized natural rubber (ENR). Liquefaction of empty fruit bunches (EFB) is carried out at different ratio of phenol to EFB (P:EFB). Resole type phenolic resin is prepared using sodium hydroxide (NaOH) as the catalyst with the ratio of liquefied EFB (LEFB) to formaldehyde (LEFB:F) of 1:1.8. 50% epoxidation of epoxidized natural rubber (ENR-50) is used to react with resole resin by mixing with ENR with aqueous resole resin. The cured resin is characterized with FT-IR and SEM. Aqueous system have been found to be unsuitable medium in the reaction between resin and ENR. This system produced a highly porous product when RLEFB/ENR resin is cured.

  12. Protein structure similarity clustering and natural product structure as guiding principles for chemical genomics.

    Science.gov (United States)

    Koch, M A; Waldmann, H

    2006-01-01

    The majority of all proteins are modularly built from a limited set of approximately 1,000 structural domains. The knowledge of a common protein fold topology in the ligand-sensing cores of protein domains can be exploited for the design of small-molecule libraries in the development of inhibitors and ligands. Thus, a novel strategy of clustering protein domain cores based exclusively on structure similarity considerations (protein structure similarity clustering, PSSC) has been successfully applied to the development of small-molecule inhibitors of acetylcholinesterase and the 11beta-hydroxysteroid dehydrogenases based on the structure of a naturally occurring Cdc25 inhibitor. The efficiency of making use of the scaffolds of natural products as biologically prevalidated starting points for the design of compound libraries is further highlighted by the development of benzopyran-based FXR ligands.

  13. Coumarin and Cinnamaldehyde in Cinnamon Marketed in Italy: a Natural Chemical Hazard?

    OpenAIRE

    Lungarini, Silvia; Aureli, Federica; Coni, Ettore

    2008-01-01

    Abstract Some plants that are processed into foods often contain natural substances that may be dangerous. One example is coumarin that is known to cause liver and kidney damage in rats, mice and probably in humans. The main source of coumarin in diet is surely cinnamon. The name cinnamon is correctly used to refer to Ceylon Cinnamon, also known as ?true cinnamon?. However, other plant species are sometimes sold with the label of cinnamon. This is the case of Cinnamomun aromaticum ...

  14. Chemical constituents of peppers (Piper spp.) and application to food preservation: naturally occurring antioxidative compounds.

    OpenAIRE

    Nakatani, N; Inatani, R; Ohta, H; Nishioka, A.

    1986-01-01

    In a structure analysis of the compounds of the genus Piper (Family Piperaceae), we identified five phenolic amides from Piper nigrum, seven compounds from P. retrofractum, and two compounds from P. baccatum. All the phenolic amides possess significant antioxidant activities that are more effective than the naturally occurring antioxidant, alpha-tocopherol. One amide, feruperine, has antioxidant activity as high as the synthetic antioxidants, butylated hydroxyanisole (BHA) and butylated hydro...

  15. 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.

  16. Luminescence and tenebrescence of natural sodalites: a chemical and structural study

    Science.gov (United States)

    Zahoransky, Teresa; Friis, Henrik; Marks, Michael A. W.

    2016-07-01

    Sodalite (Na8Al6Si6O24Cl2) shows a wide range of colours and may exhibit a variety of optical properties including cathodoluminescence, photoluminescence and tenebrescence. These optical peculiarities are not yet fully understood but are of key interest for industry. We provide a detailed study on the photochromic properties of natural sodalite, and we show that S is crucially influencing luminescence of sodalites. A reduced intensity in cathodoluminescence was observed at high S contents for some samples, showing that S can act as cathodoluminescence quencher. Photoluminescent sodalites are generally enriched in S compared to non-photoluminescent samples, although few samples being very low in S still show photoluminescence. Additionally, S was found to enlarge the unit cell in natural sodalites which might have a crucial impact on their photochromic properties. The most efficient tenebrescent samples were found to be low in Fe, Mn and S. They showed the smallest unit-cell dimensions, and a strong link between the atomic structure and the formation of F-centres is proposed. Tenebrescence in natural sodalites appears to be enhanced (1) by S but saturated at too high S concentrations and (2) by a stoichiometry and structure close to the ideal sodalite composition. In contrast to the term self-quenching for luminescence, we propose a saturation of F-centres to explain tenebrescence at different S contents.

  17. Chemical fractionation of some natural radionuclides in a soil contaminated by slags

    International Nuclear Information System (INIS)

    To investigate the chemical fractionation of 238U, 226Ra, 210Pb, and 228Ra in soils contaminated by slags from coal firing and from pyrite roasting, a sequential extraction method (modified Tessier procedure) has been applied. The following fractions were each extracted: 1, easily exchangeable; 2, bound to carbonates; 3, bound to iron-manganese oxides; 4; bound to organic matter; 5, persistently bound; 6, residual. In addition, the extractants were also analyzed for the insoluble matrix elements Al and Fe to provide some information on the effect of each extraction step on the dissolution of the matrix. The results show that the percentage amounts of these radio-nuclide in fractions 1 (238U and 210Pb released from the slag by the iron-manganese oxide extractant are subsequently reabsorbed rapidly to a considerable extent by soil minerals and thus do not appear in the iron-manganese oxide fraction 3 but rather in fractions 4 and 6. As a result of such redistribution processes, it will be almost impossible to predict quantitatively the chemical fractionation of radionuclides in contaminated soils by investigating pure slags only. 24 refs., 2 figs., 2 tabs

  18. Processes controlling the chemical composition of natural waters in the Hreppar-Land in Southern Iceland

    International Nuclear Information System (INIS)

    This contribution describes the processes controlling the chemical and isotopic composition of cold and geothermal waters (5-150 deg. C) in the Hreppar-Land area in southern Iceland. The chemical composition of surface-and cold groundwaters are controlled by the salt content of the precipitation, rock dissolution and organic CO2 from the soil. The dissolved solids content of the geothermal waters is higher than that of the cold waters and it increases with temperature. The cause is increased rock dissolution. Chloride and boron are considered to act as essentially mobile elements in the Icelandic surface- and ground water environment. The Cl-B relationships in the waters are considered to reflect that the geothermal water represents local precipitation. Yet, the δ 2H values of these waters tend to be lower than that of local waters. This difference is not considered to reflect a distant recharge areas to the geothermal systems on higher ground inland but due to the presence of a small component of ''ice-age water'' in the geothermal water that entered the bedrock during the deglaciation period, even earlier, when the δ 2H of meteoric water in Iceland was much lower than that of today's precipitation. 26 refs, 11 figs, 3 tabs

  19. The nature of chemical bond in trioxide Mi-UO3

    Directory of Open Access Journals (Sweden)

    Teterin Yury A.

    2002-01-01

    Full Text Available Low-energy X-ray photoelectron and conversion electron spectra from uranium trioxide were measured, and calculations were done for the [UO2O4]-6 (D4b cluster which reflects the structure of uranium close environment in MI-UO3 in the non-relativistic and relativistic Xa-DVM approximation. This enabled a satisfactory qualitative and in some cases quantitative agreement between the experimental and theoretical data, and interpretation of such spectra. Despite the traditional opinion that before participation in the chemical binding, the U5f electrons could be promoted to the higher (for example - U6d levels, it was theoretically proved and experimentally confirmed that the U5f electrons (about two U5f electrons are able to participate directly in the chemical bond formation in uranium trioxide. The filled U5f states proved to be localized in the outer valence molecular orbitals energy range 4-9 eV, while the vacant U5f states were generally localized in the low-energy range (0-6 eV above zero. It was experimentally shown that U6p electrons not only participate effectively in the inner valence molecular orbital formation but also participate strongly (more than 1 U6p electron in the formation of die filled outer valence molecular orbitals.

  20. Chemical nature of alkaline polyphosphate boundary film at heated rubbing surfaces

    Science.gov (United States)

    Wan, Shanhong; Tieu, A. Kiet; Zhu, Qiang; Zhu, Hongtao; Cui, Shaogang; Mitchell, David R. G.; Kong, Charlie; Cowie, Bruce; Denman, John A.; Liu, Rong

    2016-05-01

    Alkaline polyphosphate has been demonstrated to be able to reduce significant wear and friction of sliding interfaces under heavy loads (>1 GPa) and elevated temperature (800 °C and above) conditions, e.g. hot metal manufacturing. The chemical composition and fine structure of polyphosphate lubricating film is not well understood as well as the role of alkaline elements within the reaction film at hot rubbing surface. This work makes use of the coupling surface analytical techniques on the alkaline polyphosphate tribofilm, XANES, TOF-SIMS and FIB/TEM. The data show the composition in gradient distribution and trilaminar structure of tribofilm: a shorter chain phosphate overlying a long chain polyphosphate that adheres onto oxide steel base through a short chain phosphate. The chemical hardness model well explains the anti-abrasive mechanism of alkaline polyphosphate at elevated temperatures and also predicts a depolymerisation and simultaneous cross-linking of the polyphosphate glass. The role of alkaline elements in the lubrication mechanism is especially explained. This work firstly serves as a basis for a detailed study of alkaline polyphosphate tribofilm at temperature over 600 °C.

  1. Chemical structures and reactivities of coal as an organic natural product

    Energy Technology Data Exchange (ETDEWEB)

    Collins, C J; Hombach, H P; Benjamin, B M; Roark, W H; Maxwell, B; Raaen, V F

    1979-01-01

    Some chemical reactions involved in coal liquefaction have been studied using carbon 14 labelled compounds and nuclear magnetic resonance. On the basis of these studies it is concluded that the role of tetralin during coal conversion is (1) to act as a dispersion vehicle; (2) to supply hydrogen radicals, when needed, to trap coal radicals, and (3) in a very minor way to undergo intermolecular reaction with the coal through making and breaking of C--C (and possibly other) bonds. As a result of other experiments it is concluded that to the methods previously employed for breaking bonds in coal molecules and thereby lowering their molecular weights, must now be added the use of solvated-electrons for breaking -CH/sub 2/--CH/sub 2/- linkages. A possible mechanism for the cleavage of bibenzyl (used as a model compound for coal) is given. (LTN)

  2. Natural products as lead structures: chemical transformations to create lead-like libraries.

    Science.gov (United States)

    Pascolutti, Mauro; Quinn, Ronald J

    2014-03-01

    In this review, we analyze and illustrate the variation of the two main lead-like descriptors [molecular weight (MW) and the partition coefficient (logP)] in the generation of libraries in which a natural product (NP) is used as the guiding structure. Despite the different approaches used to create NP-like libraries, controlling these descriptors during the synthetic process is important to generate lead-like libraries. From this analysis, we present a schematic approach to the generation of lead-like libraries that can be applied to any starting NP. PMID:24171951

  3. 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

  4. The use of isolated natural products as scaffolds for the generation of chemically diverse screening libraries for drug discovery.

    Science.gov (United States)

    Barnes, Emma C; Kumar, Rohitesh; Davis, Rohan A

    2016-03-01

    A diverse range of strategies leading to natural product derived or inspired screening libraries aims to increase the number of new chemical entities emerging per year. However, the use of isolated natural products as scaffolds for the semi-synthesis of larger biological screening libraries remains rare. This particular method avoids the time-consuming and resource intensive de novo synthetic strategy for scaffold production, and has become more feasible through improvements to synthetic and isolation methodologies. This Highlight examines the increasing popularity of small- to large-sized screening libraries generated directly from isolated natural products. Several of the examples detailed herein show how this strategy can lead to improvements in not only potency but also other important (and often forgotten) drug discovery parameters such as toxicity, selectivity, lipophilicity and bioavailability. However, there are still improvements to be made to this method, particularly in the choice of the natural product scaffold and the derivatising reagents used. Avoidance of known nuisance compounds or structural alert motifs (e.g. PAINS) that interfere with bioactivity screens, and impact downstream drug development will play a significant role in the future success of this methodology. Incorporation of rational design strategies that take into account the physicochemical parameters (e.g. log P, MW, HBA, HBD) of the final semi-synthetic library analogues will also facilitate the discovery and development of leads and drugs. A multi-pronged approach to drug discovery that incorporates the use of isolated natural product scaffolds for library generation will surely be beneficial. PMID:26739749

  5. 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.

  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

    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...... 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...

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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 Kd 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)

  9. Partitioning of naturally-occurring radionuclides (NORM) in Marcellus Shale produced fluids influenced by chemical matrix.

    Science.gov (United States)

    Nelson, Andrew W; Johns, Adam J; Eitrheim, Eric S; Knight, Andrew W; Basile, Madeline; Bettis, E Arthur; Schultz, Michael K; Forbes, Tori Z

    2016-04-01

    Naturally-occurring radioactive materials (NORM) associated with unconventional drilling produced fluids from the Marcellus Shale have raised environmental concerns. However, few investigations into the fundamental chemistry of NORM in Marcellus Shale produced fluids have been performed. Thus, we performed radiochemical experiments with Marcellus Shale produced fluids to understand the partitioning behavior of major radioelements of environmental health concern (uranium (U), thorium (Th), radium (Ra), lead (Pb), and polonium (Po)). We applied a novel radiotracer, (203)Pb, to understand the behavior of trace-levels of (210)Pb in these fluids. Ultrafiltration experiments indicated U, Th, and Po are particle reactive in Marcellus Shale produced fluids and Ra and Pb are soluble. Sediment partitioning experiments revealed that >99% of Ra does not adsorb to sediments in the presence of Marcellus Shale produced fluids. Further experiments indicated that although Ra adsorption is related to ionic strength, the concentrations of heavier alkaline earth metals (Ba, Sr) are stronger predictors of Ra solubility. PMID:26952871

  10. 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)

  11. Morphological and chemical nature of fiber strands of oil palm empty-fruit-bunch (OPEFB

    Directory of Open Access Journals (Sweden)

    Wan Rosli Wan Daud

    2007-01-01

    Full Text Available In this work we examined the morphological and chemical characteristics of the fibrous strands of oil palm empty-fruit-bunch which were left behind after being stripped of their fruits used for oil production. The empty-fruit-bunches were mechanically loosened to yield the fibrous strands, which can be used in paper and board making. We found that the fibrous strands had unique structure by having several large-diameter, long vessel elements in their core region, surrounded by vascular fibers. They had numerous silica-bodies attached to craters on their surfaces; the craters were perforated at the bottom. Many other minerals were also present in the strands. Our microscopic observations suggested that the silica-bodies are connected to a network of siliceous pathway within the fibrous matrix, and minerals tend to concentrate adjacent to the silica-bodies. Our findings could be useful in identifying suitable techniques for processing the oil palm fiber strands into value-added products.

  12. 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.

  13. 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.

  14. Plaque biofilms: the effect of chemical environment on natural human plaque biofilm architecture.

    Science.gov (United States)

    Robinson, C; Strafford, S; Rees, G; Brookes, S J; Kirkham, J; Shore, R C; Watson, P S; Wood, S

    2006-11-01

    The architecture of microbial biofilms especially the outer regions have an important influence on the interaction between biofilm and local environment particularly on the flux of materials into and out of biofilm compartments and as a consequence, biofilm metabolic behaviour. In the case of dental plaque biofilms, architecture will determine access of nutrients including acidogenic substrates and therapeutic materials to the microbial biomass and to the underlying tooth surface. Manipulation of this architecture may offer a means of altering mass transfer into the whole biofilm and biomass and raises the possibility of improving access of therapeutics. Plaque biofilms formed in vivo on human enamel were subjected to a number of different chemical conditions while under observation by confocal laser scanning microscopy in reflection mode. In this way the outer 50-100 microm or so of the biofilms was examined. Density and distribution of biomass were recorded as degree of reflectance. The amount and density of biofilm biomass increased from the plaque saliva interface towards the interior. Plaque biofilms were robust and little affected by mechanical manipulation, high ionic strength or low pH (2.5). Detergent (SLS), however, often appeared to either remove biomass and/or dramatically reduce its density.

  15. 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.

  16. Molecular cloning and functional expression in Lactobacillus plantarum 80 of xylT, encoding the D-xylose-H+ symporter of Lactobacillus brevis

    NARCIS (Netherlands)

    Chaillou, S.; Bor, Y.-C.; Batt, C.A.; Postma, P.W.; Pouwels, P.H.

    1998-01-01

    A 3-kb region, located downstream of the Lactobacillus brevis xylA gene (encoding D-xylose isomerase), was cloned in Escherichia coli TG1. The sequence revealed two open reading frames which could code for the D-xylulose kinase gene (xylB) and another gene (xylT) encoding a protein of 457 amino acid

  17. A NUMERICAL ANALYSIS OF LANDFALL OF THE 1979 RED TIDE OF KARENIA BREVIS ALONG THE WEST COAST OF FLORIDA. (R827085)

    Science.gov (United States)

    AbstractA simple ecological model, coupled to a primitive equation circulation model, is able to replicate the observed alongshore transport of the toxic dinoflagellate Karenia brevis on the West Florida shelf during a fall red tide in 1979. Initial land fall o...

  18. Natural and Derivative Brevetoxins: Historical Background, Multiplicity, and Effects

    OpenAIRE

    Baden, Daniel G.; Bourdelais, Andrea J.; Jacocks, Henry; Michelliza, Sophie; Naar, Jerome

    2005-01-01

    Symptoms consistent with inhalation toxicity have long been associated with Florida red tides, and various causal agents have been proposed. Research since 1981 has centered on a group of naturally occurring trans-fused cyclic polyether compounds called brevetoxins that are produced by a marine dinoflagellate known as Karenia brevis. Numerous individual brevetoxins have been identified from cultures as well as from natural bloom events. A spectrum of brevetoxin derivatives produced by chemica...

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

    International Nuclear Information System (INIS)

    Hydrolysis and redox reactions of the Am(III) and Am(V) ions have been investigated in NaClO4 and NaCl solutions as well as in natural saline groundwaters. The hydrolysis constants of Am(OH)n3-n species and the solubility product of Am(OH)3(s) have been determined in 0.1 M NaClO4, 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 Cl2, 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 AmO2(OH)n1-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.)

  20. Chemically modified natural polysaccharide as green corrosion inhibitor for mild steel in acidic medium

    International Nuclear Information System (INIS)

    Highlights: ► Polyacrylamide grafted with Okra mucilage is a biodegradable co-polymer. ► It is an effective green corrosion inhibitor for mild steel in 0.5 M H2SO4. ► The inhibition efficiency is both concentration and time dependent. ► It acts as a predominantly cathodic inhibitor. ► Physically adsorbed polymer film on the metal surface restricts the corrosion. - Abstract: A new green polymeric material, polyacrylamide grafted with Okra mucilage, a natural grade polysaccharide, was tested as corrosion inhibitor for mild steel in 0.5 M H2SO4 using gravimetric and electrochemical techniques. The inhibition efficiency was found to increase with increasing inhibitor concentration up to maximum 96.6% for 100 ppm at 25 °C. The effects of immersion time (3–72 h) and temperature (25–65 °C) on the inhibition of corrosion have also been discussed. The adsorption of this inhibitor on the mild steel surface obeys a Langmuir adsorption isotherm. The scanning electron micrographs of the inhibited specimens show smoothening of the surface.

  1. 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.

  2. Evaluation of conceptual models of natural organic matter (humus) from a consideration of the chemical and biochemical processes of humification

    Science.gov (United States)

    Wershaw, Robert L.

    2004-01-01

    Natural organic matter (NOM) has been studied for more than 200 years because of its importance in enhancing soil fertility, soil structure, and water-holding capacity and as a carbon sink in the global carbon cycle. Two different types of models have been proposed for NOM: (1) the humic polymer models and (2) the molecular aggregate models. In the humic polymer models, NOM molecules are depicted as large (humic) polymers that have unique chemical structures that are different from those of the precursor plant degradation products. In the molecular aggregate models, NOM is depicted as being composed of molecular aggregates (supramolecular aggregates) of plant degradation products held together by non-covalent bonds. The preponderance of evidence favors the supramolecular aggregate models. These models were developed by studying the properties of NOM extracted from soils and natural waters, and as such, they provide only a very generalized picture of the structure of NOM aggregates in soils and natural waters prior to extraction. A compartmental model, in which the structure of the NOM in each of the compartments is treated separately, should provide a more accurate representation of NOM in soil and sediment systems. The proposed NOM compartments are: (1) partially degraded plant tissue, (2) biomass from microorganisms, (3) organic coatings on mineral grains, (4) pyrolytic carbon, (5) organic precipitates, and (6) dissolved organic matter (DOM) in interstitial water. Within each of these compartments there are NOM supramolecular aggregates that will be dissolved by the solvent systems that are used by researchers for extraction of NOM from soils and sediments. In natural water systems DOM may be considered as existing in two subcompartments: (1) truly dissolved DOM and (2) colloidal DOM.

  3. Chemical Compounds in Natural Medicines That Affect Macropharges and Adipocyte Cells.

    Science.gov (United States)

    Kitanaka, Susumu

    2016-01-01

    Macrophages play major roles in inflammation, immunity and host defense mechanisms. Once activated they produce and release cytokines, oxygen and nitrogen species, and eicosanoids. The best characterized stimuli to induce the transcription of genes encoding pro-inflammatory proteins in macrophages in vitro is bacterial lipopolysaccharide (LPS). LPS could be used alone or in combination with recombinant mouse interferon-γ (IFN-γ). Such stimulation results in cytokine release and the synthesis of enzymes such as cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). The nitric oxide (NO) radical is known to play a central role in inflammatory and immune reactions for self-protection. However, the excessive production of NO may lead to tissue damage. In inflammatory diseases such as rheumatoid arthritis, excessive NO production by activated macrophages has been observed. Adipose tissue is composed of various cell types such as mature adipocytes, preadipocytes, fibroblasts, endothelial cells, vascular cells, and macrophages. Recent studies indicate that obesity is associated with low-grade chronic inflammation of adipose tissues, and that such inflammation is one of the potential mechanisms leading to the insulin resistance. It has been demonstrated that obese adipose tissue is characterized by the increased infiltration of macrophages. Therefore, we attempted to identify natural anti-inflammatory compounds that not only inhibit the secretion of NO from RAW 264.7 cells, but also inhibit triglyceride accumulation in 3T3-L1 adipocytes. This review describes the NO prpduction inhibitory activity or the TG accumulation inhibitory activity of the compounds obtained from 18 plants and a fungi that have been used as traditional medicines. PMID:27592825

  4. Selenium Nanoparticle-Enriched Lactobacillus Brevis Causes More Efficient Immune Responses In Vivo And Reduces The Liver Metastasis In Metastatic Form Of Mouse Breast Cancer

    Directory of Open Access Journals (Sweden)

    Mohammad Esfandyar

    2013-04-01

    Full Text Available Background and the purpose of the study:Selenium enriched Lactobacillus has been reported as an immunostimulatory agent which can be used to increase the life span of cancer bearing animals. Lactic acid bacteria can reduce selenium ions to elemental selenium nanoparticles (SeNPs and deposit them in intracellular spaces. In this strategy two known immunostimulators, lactic acid bacteria (LAB and SeNPs, are concomitantly administered for enhancing of immune responses in cancer bearing mice.Methods:Forty five female inbred BALB/c mice were divided into three groups of tests and control, each containing 15 mice. Test mice were orally administered with SeNP-enriched Lactobacillus brevis or Lactobacillus brevis alone for 3 weeks before tumor induction. After that the administration was followed in three cycles of seven days on/three days off. Control group received phosphate buffer saline (PBS at same condition. During the study the tumor growth was monitored using caliper method. At the end of study the spleen cell culture was carried out for both NK cytotoxicity assay and cytokines measurement. Delayed type hypersensitivity (DTH responses were also assayed after 72h of tumor antigen recall. Serum lactate dehydrogenase (LDH and alkaline phosphatase (ALP levels were measured, the livers of mice were removed and prepared for histopathological analysis.Results:High level of IFN-γ and IL-17 besides the significant raised in NK cytotoxicity and DTH responses were observed in SeNP-enriched L. brevis administered mice and the extended life span and decrease in the tumor metastasis to liver were also recorded in this group compared to the control mice or L.brevis alone administered mice.Conclusion:Our results suggested that the better prognosis could be achieved by oral administration of SeNP-enriched L. brevis in highly metastatic breast cancer mice model.

  5. Chemical profiling of the major components in natural waxes to elucidate their role in liquid oil structuring.

    Science.gov (United States)

    Doan, Chi Diem; To, Chak Ming; De Vrieze, Mike; Lynen, Frederic; Danthine, Sabine; Brown, Allison; Dewettinck, Koen; Patel, Ashok R

    2017-01-01

    Elucidating the composition of waxes is of utmost importance to explain their behavior in liquid oil structuring. The chemical components (hydrocarbons - HCs, free fatty acids - FFAs, free fatty alcohols - FALs and wax esters - WEs) of natural waxes were analyzed using HPLC-ELSD and GC-MS followed by evaluation of their oil structuring properties. The gel strength, including the average storage modulus and oscillation yield stress, displayed a negative correlation with FALs and a positive correlation with HCs, FFAs and WEs. The components dictating the gel strength are HCs, FFAs and WEs in a descending order of importance. The consistency of the oleogels increased with the increasing amount of FFAs and HCs and the decreasing amount of WEs and FALs. The presence of more WEs results in a strong but brittle gel with a high initial flow yield stress. We believe these results might be useful in selecting the right waxes to combine in certain fat-based food products. PMID:27507530

  6. Targeting apoptosis pathways by natural compounds in cancer: marine compounds as lead structures and chemical tools for cancer therapy.

    Science.gov (United States)

    von Schwarzenberg, Karin; Vollmar, Angelika M

    2013-05-28

    Natural compounds derived from marine organisms have shown a wide variety of anti-tumor effects and a lot of attention has been drawn to further development of the isolated compounds. A vast quantity of individual chemical structures from different organisms has shown a variety of apoptosis inducing mechanisms in a variety of tumor cells. The bis-steroidal cephalostatin 1 for example, induces apoptosis via activation of caspases whereas the polyketide discodermolide inhibits cell growth by binding to and stabilizing microtubule and salisporamide A, the product of an actinobacterial strain, is an inhibitor of the proteasome. This great variety of mechanisms of action can help to overcome the multitude of resistances exhibited by different tumor specimens. Products from marine organisms and their synthetic derivates are therefore an important source for new therapeutics for single agent or combined therapy with other chemotherapeutics to support the struggle against cancer.

  7. 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.

  8. Plasma-chemical treatment of hydrogen sulfide in natural gas processing. Final report, May 1991--December 1992

    Energy Technology Data Exchange (ETDEWEB)

    Harkness, J.B.L.; Doctor, R.D. [Argonne National Lab., IL (United States)

    1993-05-01

    A new process for the treatment of hydrogen sulfide waste that uses microwave plasma-chemical technology has been under development in Russia and the United States. Whereas the present waste-treatment technology, at best, only recovers sulfur, this novel process recovers both hydrogen and sulfur by dissociating hydrogen sulfide in a plasma by means of a microwave or radio-frequency reactor. A research project has been undertaken to determine the suitability of the plasma process in natural gas processing applications. The experiments tested acid-gas compositions with 30--65% carbon dioxide, 0--7% water, and 0--0.2% of a standard mixture of pipeline gas. The balance gas in all cases was hydrogen sulfide. The reactor pressure for the experiments was 50 torr, and the microwave power was 1.0 kW. Conversions of hydrogen sulfide ranged from 80 to 100%, while 35--50% of the carbon dioxide was converted to carbon monoxide. This conversion of carbon dioxide resulted in a loss of hydrogen production and an energy loss from a hydrogen sulfide waste-treatment perspective. Tests of a direct natural gas treatment concept showed that hydrocarbon losses were unacceptably high; consequently, the concept would not be economically viable.

  9. 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

  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)

    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. 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.

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

    International Nuclear Information System (INIS)

    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.

  13. 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.

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

    International Nuclear Information System (INIS)

    Graphical abstract: Display Omitted -- Highlights: • In4Se2.85@graphene nanocomposite is easily prepared by high energy mechanical milling process. • The bond covalency of In4Se2.85 is notably changed upon the composite formation with graphene. • In4Se2.85@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 In4Se2.85@graphene and In4Se2.85@carbon-black are synthesized via a solid state reaction between In and Se elements, and the following high energy mechanical milling of In4Se2.85 with graphene and carbon-black, respectively. The high energy mechanical milling (HEMM) of In4Se2.85 with carbon species gives rise to a decrease of particle size with a significant depression of the crystallinity of In4Se2.85 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 In4Se2.85. Both the nanocomposites of In4Se2.85@graphene and In4Se2.85@carbon-black show much better anode performance for lithium ion batteries with larger discharge capacity and better cyclability than does the pristine In4Se2.85 material, indicating the beneficial effect of composite formation on the electrochemical activity of indium selenide. Between the present nanocomposites, the electrode performance of the In4Se2.85@graphene nanocomposite is superior to that of the In4Se2.85@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 In4Se2.85 and graphene. The present study clearly demonstrates that the composite formation with graphene has strong influence on the chemical bonds and electrode activity of indium

  15. Aerosol-halogen interaction: Change of physico-chemical properties of SOA by naturally released halogen species

    Science.gov (United States)

    Ofner, J.; Balzer, N.; Buxmann, J.; Grothe, H.; Krüger, H.; Platt, U.; Schmitt-Kopplin, P.; Zetzsch, C.

    2011-12-01

    Reactive halogen species are released by various sources like photo-activated sea-salt aerosol or salt pans and salt lakes. These heterogeneous release mechanisms have been overlooked so far, although their potential of interaction with organic aerosols like Secondary Organic Aerosol (SOA), Biomass Burning Organic Aerosol (BBOA) or Atmospheric Humic LIke Substances (HULIS) is completely unknown. Such reactions can constitute sources of gaseous organo-halogen compounds or halogenated organic particles in the atmospheric boundary layer. To study the interaction of organic aerosols with reactive halogen species (RHS), SOA was produced from α-pinene, catechol and guaiacol using an aerosol smog-chamber. The model SOAs were characterized in detail using a variety of physico-chemical methods (Ofner et al., 2011). Those aerosols were exposed to molecular halogens in the presence of UV/VIS irradiation and to halogens, released from simulated natural halogen sources like salt pans, in order to study the complex aerosol-halogen interaction. The heterogeneous reaction of RHS with those model aerosols leads to different gaseous species like CO2, CO and small reactive/toxic molecules like phosgene (COCl2). Hydrogen containing groups on the aerosol particles are destroyed to form HCl or HBr, and a significant formation of C-Br bonds could be verified in the particle phase. Carbonyl containing functional groups of the aerosol are strongly affected by the halogenation process. While changes of functional groups and gaseous species were visible using FTIR spectroscopy, optical properties were studied using Diffuse Reflectance UV/VIS spectroscopy. Overall, the optical properties of the processed organic aerosols are significantly changed. While chlorine causes a "bleaching" of the aerosol particles, bromine shifts the maximum of UV/VIS absorption to the red end of the UV/VIS spectrum. Further physico-chemical changes were recognized according to the aerosol size-distributions or the

  16. Effects of Synthetic and Natural Extraction Chemicals on Functional Properties, Polyphenol Content and Antioxidant Activity of Soy Protein Isolates Extracted from Full-Fat and Defatted Flours

    Directory of Open Access Journals (Sweden)

    Moses Vernonxious Madalitso Chamba

    2013-11-01

    Full Text Available The number of consumers preferring natural and organic foods to those that involve synthetic chemicals has recently shown dramatic growth. As such, a native isoelectrically precipitated soy protein isolates (SPIs were prepared from full-fat and defatted flours using amaranth (Amaranthus tricolor L. lye (pH>12.5 and lemon extract (pH<2.5 as natural food-plant-based chemicals, replacing the conventional synthetic ones (NaOH and HCl, respectively. Functional properties, total polyphenol content and antioxidant activity of the natural SPIs were compared to those of synthetic ones. All the SPI samples qualified to be soy protein isolates with a minimum protein content of 91.21%. The natural SPI showed significant increase in emulsion stability (p≤0.05. While higher values with narrow margins were shown by the synthetic than the natural SPIs in oil absorption (0.66±0.02, 0.50±0.01%, respectively, emulsion capacity (56.53±0.57, 55.50±0.39%, foam stability (11.33±0.61, 10.40±0.40%. No significant difference was observed in water absorption capacity. The DPPH assay showed increased antioxidant activity in the natural SPI although its total polyphenol content was lower. Thus, SPI with functional properties similar to those of conventional ones can be naturally processed using amaranth ash and lemon extracts as alternative chemicals to addressing the fear of consuming synthetic chemical by health-conscious natural and organic food consumers.

  17. Structure and function of natural sulphide-oxidizing microbial mats under dynamic input of light and chemical energy.

    Science.gov (United States)

    Klatt, Judith M; Meyer, Steffi; Häusler, Stefan; Macalady, Jennifer L; de Beer, Dirk; Polerecky, Lubos

    2016-04-01

    We studied the interaction between phototrophic and chemolithoautotrophic sulphide-oxidizing microorganisms in natural microbial mats forming in sulphidic streams. The structure of these mats varied between two end-members: one characterized by a layer dominated by large sulphur-oxidizing bacteria (SOB; mostly Beggiatoa-like) on top of a cyanobacterial layer (B/C mats) and the other with an inverted structure (C/B mats). C/B mats formed where the availability of oxygen from the water column was limited (45 μM) and continuously present. Here SOB were independent of the photosynthetic activity of cyanobacteria and outcompeted the cyanobacteria in the uppermost layer of the mat where energy sources for both functional groups were concentrated. Outcompetition of photosynthetic microbes in the presence of light was facilitated by the decoupling of aerobic chemolithotrophy and oxygenic phototrophy. Remarkably, the B/C mats conserved much less energy than the C/B mats, although similar amounts of light and chemical energy were available. Thus ecosystems do not necessarily develop towards optimal energy usage. Our data suggest that, when two independent sources of energy are available, the structure and activity of microbial communities is primarily determined by the continuous rather than the intermittent energy source, even if the time-integrated energy flux of the intermittent energy source is greater. PMID:26405833

  18. Dormancy in potato tuber meristems: chemically induced cessation in dormancy matches the natural process based on transcript profiles.

    Science.gov (United States)

    Campbell, Michael; Segear, Erika; Beers, Lee; Knauber, Donna; Suttle, Jeffrey

    2008-11-01

    Meristem dormancy in perennial plants is a developmental process that results in repression of metabolism and growth. The cessation of dormancy results in rapid growth and should be associated with the production of nascent transcripts that encode for gene products controlling for cell division and growth. Dormancy cessation was allowed to progress normally or was chemically induced using bromoethane (BE), and microarray analysis was used to demonstrate changes in specific transcripts in response to dormancy cessation before a significant increase in cell division. Comparison of normal dormancy cessation to BE-induced dormancy cessation revealed a commonality in both up and downregulated transcripts. Many transcripts that decrease as dormancy terminates are inducible by abscisic acid particularly in the conserved BURP domain proteins, which include the RD22 class of proteins and in the storage protein patatin. Transcripts that are associated with an increase in expression encoded for proteins in the oxoglutarate-dependent oxygenase family. We conclude that BE-induced cessation of dormancy initiates transcript profiles similar to the natural processes that control dormancy. PMID:18317824

  19. The evolution of chemical nature on U–0.79 wt.%Ti surface during vacuum annealing

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Peng [China Academy of Engineering Physics, Mianyang 621900 (China); Luo, Lizhu [Science and Technology on Surface Physics and Chemistry Laboratory, P.O. Box 718-35, Mianyang 621907 (China); Zhao, Yawen; Fu, Xiaoguo [China Academy of Engineering Physics, Mianyang 621900 (China); Ao, Bingyun; Bai, Bin [Science and Technology on Surface Physics and Chemistry Laboratory, P.O. Box 718-35, Mianyang 621907 (China); Wang, Xiaolin, E-mail: xlwang@caep.cn [China Academy of Engineering Physics, Mianyang 621900 (China)

    2015-07-15

    Graphical abstract: The evolution of the U–0.79Ti alloy surface character during vacuum annealing. - Highlights: • The evolution of surface character of U–0.79Ti during vacuum annealing was in situ studied by XPS. • The formation and later decomposition of an oxycarbide layer were observed during the vacuum annealing from R.T. to 700 °C. • A surface segregation of titanium was noticed during high-T heat-treatment in vacuum. - Abstract: The evolution of the oxide-overlayer's chemical nature on the surface of U–0.79 wt.%Ti alloy during vacuum annealing has been examined in situ by X-ray photoelectron spectroscopy (XPS). A specimen sheet of the alloy covered by oxide films is heated from room temperature to 700 °C in vacuum. It is found that the UO{sub 2+x} outer oxide layer starts to be reduced to UO{sub 2} at 200 °C. Between 300 and 400 °C, an oxycarbide (UO{sub x}C{sub y}) layer is observed due to the reaction between UO{sub 2} and carbon. Above 500 °C, UO{sub x}C{sub y} decomposes and the surface covered oxide layer starts to be reduced to the metallic state, meanwhile, a thermal driven segregation of Ti to the surface is also observed.

  20. Taxonomy of Pimelodus brevis Marini, Nichols & La Monte, 1933 (Siluriformes: Pimelodidae, an uncertain species from the rio Paraná basin

    Directory of Open Access Journals (Sweden)

    Marcelo Salles Rocha

    2014-12-01

    Full Text Available Pimelodus brevisMarini, Nichols & La Monte, 1933 was described from the río de la Plata, Departamento San Fernando, Argentina, based only on the holotype, which is missing since 1960s. This species has been cited in the literature and is considered valid despite of no voucher specimen has been found in museum. A taxonomic analysis comprising material from the rio Paraná basin provided additional specimens that made it possible to demonstrate the identity of P. brevis. Based on the original description and illustration of the holotype, we performed an allometric analysis and then we were able to compare the data with the similar sympatric congeners. Those comparisons allowed us to conclude that P. brevisis a junior synonym of P. argenteusPerugia, 1891, described from the río Paraná, Colonia Resistencia, Argentina. Comments on the status of congeners and taxonomic recommendations are provided.

  1. Prevalencia de Demodex folliculorum e Demodex brevis em uma amostra da população de Botucatu, São Paulo, Brasil

    Directory of Open Access Journals (Sweden)

    N.G. Madeira

    1993-12-01

    Full Text Available Pela primeira vez no Brasil foi realizado um levantamento para se conhecer a distribuição do D. folliculorum e D. brevis no homem. Uma amostra de 100 pessoas atendida em clínica estética foi examinada, procurando-se estudar a associação entre a presença de ácaros e fatores como idade, raça e sexo do hospedeiro. O material colhido da região facial dos indivíduos foi montado em lâminas com o meio de Berlese. Das 100 pessoas examinadas, 72 % foram positivas. Dos casos positivos, 51 % estavam infestados pelo D. folliculorum, 2% pelo D. brevis e 19% apresentaram-se parasitados por ambas as espécies.

  2. A 1-D simulation analysis of the development and maintenance of the 2001 red tide of the ichthyotoxic dinoflagellate Karenia brevis on the West Florida shelf

    Science.gov (United States)

    Lenes, J. M.; Darrow, B. P.; Walsh, J. J.; Jolliff, J. K.; Chen, F. R.; Weisberg, R. H.; Zheng, L.

    2012-06-01

    A one-dimensional (1-D) ecological model, HABSIM, examined the initiation and maintenance of the 2001 red tide on the West Florida shelf (WFS). Phytoplankton competition among toxic dinoflagellates (Karenia brevis), nitrogen fixing cyanophytes (Trichodesmium erythraeum), large siliceous phytoplankton (diatoms), and small non-siliceous phytoplankton (microflagellates) explored the sequence of events required to support the observed red tide from August to December 2001. The ecological model contained 24 state variables within five submodels: circulation, atmospheric (iron deposition), bio-optics, pelagic (phytoplankton, nutrients, bacteria, zooplankton, and fish), and benthic (nutrient regeneration). The 2001 model results reaffirmed that diazotrophs are the basis for initiation of red tides of K. brevis on the WFS. A combination of selective grazing pressure, iron fertilization, low molar nitrogen to phosphorus ratios, and eventual silica limitation of fast-growing diatoms set the stage for dominance of nitrogen fixers. "New" nitrogen was made available for subsequent blooms of K. brevis through the release of ammonium and urea during nitrogen fixation, as well as during cell lysis, by the Trichodesmium population. Once K. brevis biomass reached ichthyotoxic levels, rapid decay of subsequent fish kills supplied additional organic nutrients for utilization by these opportunistic toxic algae. Both nutrient vectors represented organic non-siliceous sources of nitrogen and phosphorus, further exacerbating silica limitation of the diatom population. The model reproduced this spring transition from a simple estuarine-driven, diatom-based food chain to a complex summer-fall system of Trichodesmium and toxic dinoflagellates. While the model was able to replicate the initiation and maintenance of the 2001 red tide, bloom termination was not captured by this 1-D form on the WFS. Here, horizontal advection and perhaps cell lysis loss terms might play a significant role, to be

  3. Prevalencia de Demodex folliculorum e Demodex brevis em uma amostra da população de Botucatu, São Paulo, Brasil

    Directory of Open Access Journals (Sweden)

    N.G. Madeira

    1993-12-01

    Full Text Available Pela primeira vez no Brasil foi realizado um levantamento para se conhecer a distribuição do D. folliculorum e D. brevis no homem. Uma amostra de 100 pessoas atendida em clínica estética foi examinada, procurando-se estudar a associação entre a presença de ácaros e fatores como idade, raça e sexo do hospedeiro. O material colhido da região facial dos indivíduos foi montado em lâminas com o meio de Berlese. Das 100 pessoas examinadas, 72 % foram positivas. Dos casos positivos, 51 % estavam infestados pelo D. folliculorum, 2% pelo D. brevis e 19% apresentaram-se parasitados por ambas as espécies.A survey was conduced to determine the prevalence of D. folliculorum and D. brevis for the first time in Brazil. In this study, association between the presence of mites and hostfactors (age, sex and race were anatysed. Samples were obtained from 100 individuals submitted to a facial cleaning in an aesthetic clinic in Botucatu city. All the samples were mounted in Berleses medium and examined by dark-field phase microscopy. From 100 studied individuais, 72 were positive, among the positive cases, 51% showed D. folliculorum, 2% showed D. brevis and 19% both species. The parasite distribution in realtion to sex was not taken in account because the sex ratio tavoured females (90%. According to age, prevalence was high in all age groups. The factors influencing this distribution could be due. 1. the examination of extensive skin areas, 2. the group examined composed of individuals in treatment in an anaesthetic clinic could be more infested than a normal population, 3. the fact that in tropics, the prevalence is often high in all ages.

  4. A Harmful Algal Bloom of Karenia brevis in the Northeastern Gulf of Mexico as Revealed by MODIS and VIIRS: A Comparison

    OpenAIRE

    Chuanmin Hu; Barnes, Brian B.; Lin Qi; Corcoran, Alina A.

    2015-01-01

    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 i...

  5. 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.

  6. Multi-Sensor Approach for the Monitoring of Halitosis Treatment via Lactobacillus brevis (CD2)-Containing Lozenges--A Randomized, Double-Blind Placebo-Controlled Clinical Trial.

    Science.gov (United States)

    Marchetti, Enrico; Tecco, Simona; Santonico, Marco; Vernile, Chiara; Ciciarelli, Daniele; Tarantino, Ester; Marzo, Giuseppe; Pennazza, Giorgio

    2015-01-01

    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. PMID:26266414

  7. 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

    2013-01-01

    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…

  8. 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.

  9. 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.

  10. 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. PMID:26938082

  11. 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.

  12. VirtualToxLab - a platform for estimating the toxic potential of drugs, chemicals and natural products.

    Science.gov (United States)

    Vedani, Angelo; Dobler, Max; Smieško, Martin

    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.

  13. The effect of chemical treatment on adsorption of natural gas by multi-walled carbon nanotubes: Sorption equilibria and thermodynamic studies

    Directory of Open Access Journals (Sweden)

    Delavar M.

    2012-01-01

    Full Text Available In this study, adsorption of methane as the main constituent of natural gas was firstly studied on the pristine multi-walled carbon nanotubes (MWCNTs and then purification and chemical treatments of MWCNTs was performed to enhance the natural gas adsorption capacity. MWCNTs were chemically treated using different methods in this research. The results revealed that chemical treatment of the MWCNTs in presence of H2SO4/HNO3 acidic mixture in 3:1 volume ratio, enhanced considerably natural gas adsorption capacity (an optimal up to 45 mmol/g at temperature of 298.15 K and the pressure of 50 bar compared to the pristine MWCNTs (about 27 mmol/g at the same operating conditions. This effect can be attributed to the opening of the nanotubes caps with a major alteration in its structural properties due to chemical treatment. The experimental data of adsorption were almost equally well described by Langmuir, Freundlich and Sips equations to determine the model isotherms. The best fit was obtained by the Sips model isotherm with the r-squared value near to unity. Furthermore, using the experimental data obtained in different temperatures the isosteric heat of natural gas adsorption onto pristine MWCNTs was also calculated in the interested range of pressures and temperatures using the thermodynamic-based Clausius-Clapeyron equation from the Sips isotherm model. The results revealed an energetically heterogeneous surface of MWCNTs in natural gas adsorption. Also the natural gas adsorption process was kinetically studied through pseudo-second order and intra-particle diffusion models which indicated the intra-particular diffusion is rate limiting step in adsorption of methane on MWCNTs.

  14. Biosorption and degradation of decabromodiphenyl ether by Brevibacillus brevis and the influence of decabromodiphenyl ether on cellular metabolic responses.

    Science.gov (United States)

    Wang, Linlin; Tang, Litao; Wang, Ran; Wang, Xiaoya; Ye, Jinshao; Long, Yan

    2016-03-01

    There is global concern about the effects of decabromodiphenyl ether (BDE209) on environmental and public health. The molecular properties, biosorption, degradation, accumulation, and cellular metabolic effects of BDE209 were investigated in this study to identify the mechanisms involved in the aerobic biodegradation of BDE209. BDE209 is initially absorbed by wall teichoic acid and N-acetylglucosamine side chains in peptidoglycan, and then, BDE209 is transported and debrominated through three pathways, giving tri-, hepta-, octa-, and nona-bromodiphenyl ethers. The C-C bond energies decrease as the number of bromine atoms on the diphenyl decreases. Polybrominated diphenyl ethers (PBDEs) inhibit protein expression or accelerate protein degradation and increase membrane permeability and the release of Cl(-), Na(+), NH4 (+), arabinose, proteins, acetic acid, and oxalic acid. However, PBDEs increase the amounts of K(+), Mg(2+), PO4 (3-), SO4 (2-), and NO3 (-) assimilated. The biosorption, degradation, accumulation, and removal efficiencies when Brevibacillus brevis (1 g L(-1)) was exposed to BDE209 (0.5 mg L(-1)) for 7 days were 7.4, 69.5, 16.3, and 94.6 %, respectively. PMID:26555880

  15. Potential distribution and cost estimation of the damage caused by Cryptotermes brevis (Isoptera: Kalotermitidae) in the Azores.

    Science.gov (United States)

    Guerreiro, O; Cardoso, P; Ferreira, J M; Ferreira, M T; Borges, P A V

    2014-08-01

    In the Azores archipelago, a significant proportion of buildings are infested with the urban exotic drywood termite Cryptotermes brevis (Walker), causing major economical and patrimonial losses. This work aims to understand the potential spread of this termite species in the Azores and estimate the costs for both treatment and reconstruction of infested buildings in the entire archipelago. A maximum entropy niche modeling process was used to determine the potential occurrence of the species on each island. Different scenarios were built using independent global and regional incidence and environmental data. Both projections reveal the same pattern. Generally, the probability of occurrence is higher near the coast line, where, in Azores, the majority of the towns and villages are located. We also predict that the infestation has potential to spread to yet unaffected towns and islands. It is estimated that the cost of treating all currently infested buildings in the archipelago is Euro 51 million, while reconstruction of the same buildings would rise the costs to Euro 175 million. We predict that the absence of a control strategy will cause a further expansion of the pest to more localities in the Azores. An estimate to future scenarios implies higher costs, with treatment and rebuilding values rising up to eight times the current values.

  16. A study of chemical composition and radiation attenuation properties in clinoptilolite-rich natural zeolite from Turkey

    International Nuclear Information System (INIS)

    Clinoptilolite, a type of natural zeolite, has been commonly used as pozzolanic additive in concrete. This type of natural zeolite is generally used as a mineral admixture by substitution in Portland cement to produce high performance concretes. In the present study, the major, minor and trace element levels present in the clinoptilolite-rich natural zeolite (CRNZ) have been determined using a wavelength dispersive X-ray fluorescence spectrometer. Also, the clinoptilolite-rich natural zeolite has been compared with Portland cement with respect to the radiation attenuation properties. From the results it can be concluded that due to the natural radioactive content of clinoptilolite-rich natural zeolite (CRNZ) even if it is in trace level and also due to the poorer X-ray attenuation compared with Portland cement, special care should be taken to use this type of natural zeolite as blend materials in cements, etc.

  17. [The sanitary status of natural waters on the territory of Moscow (according to the results of the examination of chemical and radionuclide composition)].

    Science.gov (United States)

    Klimenko, I A; Poliakov, V A; Sokolovskiĭ, L G; Aksenova, O I; Skvortsova, O Iu; Okhrimenko, S E

    2003-01-01

    The paper presents the results of examination of the chemical and radionuclide composition of natural waters and snow cover in Moscow. Areas with abnormal contents of tritium are found in the underground and surface waters and snow cover. The high concentrations of strontium, boron, fluorine, and barium are ascertained to be associated with natural factors. Areas of technogenically polluted underground waters are identified. Recommendations are given for further studies. Particular emphasis is laid on that the artesian wells that are a reservoir source of water supply under emergency are to be revised.

  18. TREATMENT OF HYDROCARBON, ORGANIC RESIDUE AND PRODUCTION CHEMICAL DAMAGE MECHANISMS THROUGH THE APPLICATION OF CARBON DIOXIDE IN NATURAL GAS STORAGE WELLS

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence J. Pekot; Ron Himes

    2004-05-31

    Core specimens and several material samples were collected from two natural gas storage reservoirs. Laboratory studies were performed to characterize the samples that were believed to be representative of a reservoir damage mechanism previously identified as arising from the presence of hydrocarbons, organic residues or production chemicals. A series of laboratory experiments were performed to identify the sample materials, use these materials to damage the flow capacity of the core specimens and then attempt to remove or reduce the induced damage using either carbon dioxide or a mixture of carbon dioxide and other chemicals. Results of the experiments showed that pure carbon dioxide was effective in restoring flow capacity to the core specimens in several different settings. However, in settings involving asphaltines as the damage mechanism, both pure carbon dioxide and mixtures of carbon dioxide and other chemicals provided little effectiveness in damage removal.

  19. Dalian Institute of Chemical Physics/Chinese Academy of Sciences and Elsevier Signed a Publishing Agreement of the Journal of Natural Gas Chemistry

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ Dalian Institute of Chemical Physics (DICP)/Chinese Academy of Sciences (CAS) and Elsevier have concluded a publishing agreement for the Journal of Natural Gas Chemistry (JNGC) on June 07, 2005. Beginning from 2006, Elsevier will publish JNGC on ScienceDirect, the online full text and bibliographic information resource, and take care of JNGC's international institutional print subscriptions. JNGC will also be covered in Elsevier's EI Compendex.

  20. The equidosimetric approach to comparing the action of radioactive and chemical pollutions on natural populations of hydrobionts

    International Nuclear Information System (INIS)

    For the equidosimetric assessment of ionizing radiation and chemical pollutants, it is proposed to compare effects in mutagenically equivalent doses (i.e., those inducing the equal number of cells with chromosome aberrations) by using such criteria as the distribution of chromosome aberrations in cells and the number of aberrations per aberrant cell. On the basis of this approach, the equidosimetric assessment of radioactive and chemical pollution in two water bodies from the ChNPP zone is made

  1. The structure of Lactobacillus brevis surface layer reassembled on liposomes differs from native structure as revealed by SAXS.

    Science.gov (United States)

    Kontro, Inkeri; Wiedmer, Susanne K; Hynönen, Ulla; Penttilä, Paavo A; Palva, Airi; Serimaa, Ritva

    2014-08-01

    The reassembly of the S-layer protein SlpA of Lactobacillus brevis ATCC 8287 on positively charged liposomes was studied by small angle X-ray scattering (SAXS) and zeta potential measurements. SlpA was reassembled on unilamellar liposomes consisting of 1-palmitoyl-2-oleyl-sn-glycero-3-phosphocholine and 1,2-dioleoyl-3-trimethylammonium-propane, prepared by extrusion through membranes with pore sizes of 50nm and 100nm. Similarly extruded samples without SlpA were used as a reference. The SlpA-containing samples showed clear diffraction peaks in their SAXS intensities. The lattice constants were calculated from the diffraction pattern and compared to those determined for SlpA on native cell wall fragments. Lattice constants for SlpA reassembled on liposomes (a=9.29nm, b=8.03nm, and γ=84.9°) showed a marked change in the lattice constants b and γ when compared to those determined for SlpA on native cell wall fragments (a=9.41nm, b=6.48nm, and γ=77.0°). The latter are in good agreement with values previously determined by electron microscopy. This indicates that the structure formed by SlpA is stable on the bacterial cell wall, but SlpA reassembles into a different structure on cationic liposomes. From the (10) reflection, the lower limit of crystallite size of SlpA on liposomes was determined to be 92nm, corresponding to approximately ten aligned lattice planes. PMID:24796504

  2. Commentary on effects of anthropogenic and natural organic chemicals on development, swimming behavior, and reproduction of Daphnia, a key member of aquatic ecosystems.

    Science.gov (United States)

    Dodson, S I; Hanazato, T

    1995-05-01

    Because of their trophodynamic role, small invertebrates are often critical components of ecosystems. An especially important group of freshwater invertebrates is the water fleas of the genus Daphnia. These animals are often the dominant herbivores in lakes and ponds. They play a key role in determining water clarity (by grazing on algae) and they are an important part of the diet of fish. Natural chemical signals (kairomones) produced by predators affect the development, life history strategy, and behavior of zooplankton. Laboratory studies of anthropogenic chemicals that have biological activity (xenobiotics), such as the insecticide carbaryl, have demonstrated effects of concentrations in the 1 to 5 ppb range on Daphnia development, growth rate, and swimming behavior in our laboratory experiments. Low concentrations of carbaryl inhibit growth and reproduction and delay maturation, whereas survivorship was not effected. These sublethal exposures to carbaryl reduced Daphnia population growth rate (productivity) by about 15% (at 5 ppb), enough to have significant ecological effects on the rest of the lake community. The insecticide carbaryl showed synergistic interactions with natural chemicals associated with predators (kairomones) that modify Daphnia development and life history characteristic. In addition, there were complex synergisms between carbaryl, the predator odors, and oxygen concentration (low oxygen concentration can be either a natural environmental stress or an anthropogenic stress). Daphnia produce males facultatively, usually in late fall; at other times, reproduction is asexual.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7556027

  3. Brevicompanine C, cyclo-(D-Ile-L-Trp), and cyclo-(D-Leu-L-Trp), plant growth regulators from Penicillium brevi-compactum.

    Science.gov (United States)

    Kimura, Yasuo; Sawada, Aya; Kuramata, Masato; Kusano, Miyako; Fujioka, Shozo; Kawano, Tsuyoshi; Shimada, Atsumi

    2005-02-01

    New plant growth regulators, named brevicompanine C (1), cyclo-(D-Ile-L-Trp) (2), and cyclo-(D-Leu-L-Trp) (3), have been isolated from Penicillium brevi-compactum Dierckx, and their structures have been established by spectroscopic methods including 2D NMR and chiral TLC analysis. Plant growth activities of 1, 2, and 3 have been examined using lettuce seedling bioassay methods. All compounds accelerated the root growth of the seedlings in proportion to their concentration from 1 to 100 mg/L.

  4. Molecular cloning of an ornithine-activating fragment of the gramicidin S synthetase 2 gene from Bacillus brevis and its expression in Escherichia coli.

    OpenAIRE

    Krause, M.; Marahiel, M A; von Döhren, H; Kleinkauf, H

    1985-01-01

    Partially digested chromosomal DNA of Bacillus brevis ATCC 9999, a producer of the cyclic peptide antibiotic gramicidin S, was ligated into the BamHI site of the Escherichia coli expression vector pUR2-Bam. The ligated molecules were used to transfer E. coli to ampicillin resistance. Of 5 X 10(3) colonies tested by in situ immunoassay for a cross-reaction with antibodies against the gramicidin S synthetase 2, 6 colonies were found to be immunoreactive. A clone designated MK2, which had a 3.9-...

  5. Study of the influence on radiation, chemical and thermic treatment in Cesium and Cobalt absorption in natural zeolites

    International Nuclear Information System (INIS)

    The influence of radiation and thermic treatment of zeolites from El Piojillo (Villa Clara), Orozco (Pinar del Rio) and Palmarito (Santiago de Cuba) deposits in the absorption of cesium-137 is studied. It was verified that as it generally occurs in zeolites, the thermic treatment influences negatively the absorption and the radiation treatment with dose up to 105 Gy does not affect it. Alternatives to chemical and chemical-thermic treatment for zeolite from El Piojillo are also applied. It was noted that previous treatment with NH4OH at 2000C in the vacuum stove and its contact in dynamic regime with NaNO3 improves its capacity of cobalt absorption

  6. Long-term effects of oral tea polyphenols and Lactobacillus brevis M8 on biochemical parameters, digestive enzymes, and cytokines expression in broilers

    Institute of Scientific and Technical Information of China (English)

    Hua-li LI; Zong-jun LI; Zhong-shan WEI; Ting LIU; Xiao-zuo ZOU; Yong LIAO; Yu LUO

    2015-01-01

    This study investigates the long-term effects of oral tea polyphenols (TPs) and Lactobacillus brevis M8 (LB) on biochemical parameters, digestive enzymes, and cytokines expression in broilers. In experiment 1, 240 broiler chickens were selected to investigate the effects of 0.06 g/kg body weight (BW) TP and 1.0 ml/kg BW LB on broilers;in experiment 2, 180 broiler chickens were assigned randomly to three groups to investigate the effects of different dosages of TP (0.03, 0.06, and 0.09 g/kg BW) combined with 1.0 ml/kg BW LB on broilers;in experiment 3, 180 broiler chickens were assigned randomly to three groups to investigate the effects of different dosages of LB (0.5, 1.0, and 1.5 ml/kg BW) combined with 0.06 g/kg BW TP on broilers. The results showed that TP and LB affected serum bio-chemical parameters, and TP reduced serum cholesterol (CHO) and low-density lipoprotein cholesterol (LDL-C) abundances in a dosage-dependent manner (P  目的:茶多酚和乳酸菌在动物营养上的作用已经得到广泛的验证,但是关于二者联合作用的研究鲜有报道。本文采用肉鸡作为试验模型,研究了茶多酚和乳酸菌联合灌喂对肉鸡血液生化、消化酶以及肠道细胞因子表达的影响。  创新点:本研究首次采用联合灌喂茶多酚和乳酸菌,探讨了二者联合作用对肉鸡的影响,并通过模拟生产,长期观察了茶多酚和乳酸菌对肉鸡的影响。  方法:对肉仔鸡灌喂不同浓度的茶多酚和乳酸菌,在第56和84天随机屠宰取样。收集血液检查血液生化指标,并测定消化酶活性。取肠道样品提取RNA,采用反转录聚合酶链反应(RT-PCR)检测细胞因子的表达以及相关信号通路的激活。  结论:长期灌喂茶多酚和乳酸菌改善了肉鸡脂质代谢、消化酶活性以及炎症反应,其机制可能是通过影响了NF-κB信号通路。

  7. Chemical structural studies of natural lignin by dipolar dephasing solid-state 13C nuclear magnetic resonance

    Science.gov (United States)

    Hatcher, P.G.

    1987-01-01

    Two natural lignins, one from a gymnosperm wood the other from angiosperm wood, were examined by conventional solid-state and dipolar dephasing 13C nuclear magnetic resonance (NMR) techniques. The results obtained from both techniques show that the structure of natural lignins is consistent with models of softwood and hardwood lignin. The dipolar dephasing NMR data provide a measure of the degree of substitution on aromatic rings which is consistent with the models. ?? 1987.

  8. "To Improve Our Knowledge in Nature and Arts": A History of Chemical Education in the United States.

    Science.gov (United States)

    Lewenstein, Bruce V.

    1989-01-01

    Discusses a history exhibit of the American Chemical Society, now on national tour. Focuses on lecture to laboratory, chemistry in early America, the Civil War era, the research model, the early twentieth century, the post-war era, textbooks, and the recent past. (MVL)

  9. Revisiting the Chemistry Triplet: Drawing upon the Nature of Chemical Knowledge and the Psychology of Learning to Inform Chemistry Education

    Science.gov (United States)

    Taber, Keith S.

    2013-01-01

    Much scholarship in chemical education draws upon the model of there being three "levels" at which the teaching and learning of chemistry operates, a notion which is often represented graphically in terms of a triangle with the apices labelled as macroscopic, submicroscopic and symbolic. This model was proposed by Johnstone who argued that…

  10. 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

    2005-01-01

    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 architec

  11. Unifying natural and laboratory chemical weathering with interfacial dissolution-reprecipitation: A study based on the nanometer-scale chemistry of fluid-silicate interfaces

    International Nuclear Information System (INIS)

    Chemical weathering reactions of rocks at Earth's surface play a major role in the chemical cycle of elements, and represent one of the major abiotic sinks for atmospheric CO2. Because natural chemical weathering reactions occur at different and more complex chemical conditions than laboratory-based weathering experiments, it has long been thought that the underlying fluid-mineral interaction mechanisms are different. In contrast to most previous studies that have relied on ion, electron, and X-ray beam techniques (characterized by pm to mm lateral spatial resolution) to obtain chemical depth profiles of altered mineral surfaces, we have used high resolution and energy filtered transmission electron microscopy (HRTEM, EFTEM) to study mineral-fluid interfaces using TEM foils cut directly across the reaction boundaries. This allowed measurements to be made directly in cross section at nanometer to sub-nanometer-resolution. Our measurements of the surface chemistry and structure of a large suite of laboratory-altered and field-weathered silicate minerals indicate the general presence of surface layers composed of amorphous, hydrated silica. In each case, the boundary between the parent mineral and the corresponding silica layer is characterized by sharp, nanometer-scale chemical concentration jumps that are spatially coincident with a very sharp crystalline-amorphous interfacial boundary. TEM, atomic force microscopy (AFM), and aqueous chemistry data suggest that the surface layers are permeable to fluids. Taken together, our measurements are not in agreement with currently accepted models for chemical weathering, in particular the leached layer theory. Most importantly, our data provide critical evidence for a single mechanism based on interfacial dissolution-reprecipitation. This concept not only unifies weathering processes for the first time, but we also suggest that nanoscale-surface processes can have a potentially negative impact on CO2 uptake associated with

  12. 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

  13. Geochemical and fluid dynamic investigations into the nature of chemical heterogeneity in the earth's mantle. Doctoral thesis

    Energy Technology Data Exchange (ETDEWEB)

    Hauri, E.H.

    1992-09-01

    Variations in the abundances of elements and radiogenic isotopes in mantle derived periodotites and volcanic rocks are chemical integrals over time, space, and process, which ultimately contain information about the role of convection in the earth's mantle in creating, maintaining, and destroying geochemical heterogeneities. Successful inversion of these integrals extensive of these integrals requires extensive knowledge of the geochemical behavior of elements, the length scales of chemical variability, the evolution with time of geologic systems, the physical properties of mantle rocks, and the driving forces of phenomena which govern heat and mass transport in a dynamic earth. This dissertation attempts to add to this knowledge by examining the trace element and isotope geochemistry of mantle periodotites and oceanic island basalts, and by studying aspects of the flow of viscous fluids driven by thermal buoyancy.

  14. TREATMENT OF HYDROCARBON, ORGANIC RESIDUE AND PRODUCTION CHEMICAL DAMAGE MECHANISMS THROUGH THE APPLICATION OF CARBON DIOXIDE IN NATURAL GAS STORAGE WELLS

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence J. Pekot

    2004-06-30

    Two gas storage fields were studied for this project. Overisel field, operated by Consumer's Energy, is located near the town of Holland, Michigan. Huntsman Storage Unit, operated by Kinder Morgan, is located in Cheyenne County, Nebraska near the town of Sidney. Wells in both fields experienced declining performance over several years of their annual injection/production cycle. In both fields, the presence of hydrocarbons, organic materials or production chemicals was suspected as the cause of progressive formation damage leading to the performance decline. Core specimens and several material samples were collected from these two natural gas storage reservoirs. Laboratory studies were performed to characterize the samples that were believed to be representative of a reservoir damage mechanism previously identified as arising from the presence of hydrocarbons, organic residues or production chemicals. A series of laboratory experiments were performed to identify the sample materials, use these materials to damage the flow capacity of the core specimens and then attempt to remove or reduce the induced damage using either carbon dioxide or a mixture of carbon dioxide and other chemicals. Results of the experiments showed that pure carbon dioxide was effective in restoring flow capacity to the core specimens in several different settings. However, in settings involving asphaltines as the damage mechanism, both pure carbon dioxide and mixtures of carbon dioxide and other chemicals provided little effectiveness in damage removal.

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

    International Nuclear Information System (INIS)

    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

  16. 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 (p<0.05). These results indicate that a relatively low electric-field strength of 10 kV/cm can be used to pasteurize low-fat milk. PMID:26877640

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

    Science.gov (United States)

    Ramos, Cíntia Lacerda; Thorsen, Line; Ryssel, Mia; Nielsen, Dennis S; Siegumfeldt, Henrik; Schwan, Rosane Freitas; Jespersen, Lene

    2014-04-01

    In the present work, an in vitro model of the gastrointestinal tract (GIT) was developed to obtain real-time observations of the pH homeostasis of single cells of probiotic Lactobacillus spp. strains as a measure of their physiological state. Changes in the intracellular pH (pHi) were determined 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 (pH 6.4), gastric (pH 3.5) and intestinal juices (pH 6.4), respectively. When nutrients were added to gastric juice, the isolate L. brevis significantly decreased its pH(i) closer to the extracellular pH (pH(ex)) than in gastric juice without nutrients. This was not the case for L. plantarum. This study is the first to produce an in vitro GIT model enabling real-time monitoring of pH homeostasis of single cells in response to the wide range of pH(ex) of the GIT. Furthermore, it was possible to observe the heterogeneous response of single cells. The technique can be used to determine the survival and physiological conditions of potential probiotics and other microorganisms during passage through the GIT.

  18. Survival of the biocontrol agents Brevibacillus brevis ZJY-1 and Bacillus subtilis ZJY-116 on the spikes of barley in the field

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xin; ZHANG Bing-xin; ZHANG Zhen; SHEN Wei-feng; YANG Ching-hong; YU Jing-quan; ZHAO Yu-hua

    2005-01-01

    Fusarium head blight (FHB) caused by Fusarium graminearum is a devastating disease that results in extensive yield losses to wheat and barley. A green fluorescent protein (GFP) expressing plasmid pRP22-GFP was constructed for monitoring the colonization of two biocontrol agents, Brevibacillus brevis ZJY-1 and Bacillus subtilis ZJY-116, on the spikes of barley and their effect on suppression of FHB. Survival and colonization of the Brevibacillus brevis ZJY- 1 and Bacillus subtilis ZJY- 116 strains on spikes of barley were observed by tracking the bacterial transformants with GFP expression. Our field study revealed that plasmid pRP22-GFP was stably maintained in the bacterial strains without selective pressure. The retrieved GFP-tagged strains showed that the bacterial population fluctuation accorded with that of the rain events. Furthermore, both biocontrol strains gave significant protection against FHB on spikes of barley in fields. The greater suppression of barley FHB disease was resulted from the treatment of barley spikes with biocontrol agents before inoculation with F. graminearum.

  19. On the chemical nature of boundary lubrication of stainless steel by chlorine - and sulfur-containing EP-additives

    DEFF Research Database (Denmark)

    Petrushina, Irina; Christensen, Erik; Bergqvist, Rene Stig;

    2000-01-01

    The nature of the extreme pressure CEP) effect of the dialkylpolysulfides and chlorinated paraffins during the ironing of stainless steel AISI 304 has been studied. A strip reduction test was used in combination with differential thermal analysis (DTA), profilometry, X-ray photoelectron...

  20. Effects of bioleaching on the chemical, mineralogical and morphological properties of natural and waste-derived alkaline materials

    OpenAIRE

    Chiang, Yi Wai; Santos, Rafael; Monballiu, Annick; Ghyselbrecht, Karel; Martens, Johan; Mattos, Maria Laura T.; Van Gerven, Tom; Meesschaert, Boudewijn

    2013-01-01

    Bioleaching is a potential route for the valorisation of low value natural and waste alkaline materials. It may serve as a pre-treatment stage to mineral carbonation and sorbent synthesis processes by increasing the surface area and altering the mineralogy of the solid material and by generating an alkaline rich (Ca and Mg) aqueous stream. It may also aid the extraction of high value metals from these materials (e.g. Ni), transforming them into valuable ore reserves. The bioleaching potential...

  1. 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.

  2. 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.

  3. 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...

  4. “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.

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

    International Nuclear Information System (INIS)

    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

  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. Sequential chemical treatment of radium species in TENORM waste sludge produced from oil and natural gas production

    Energy Technology Data Exchange (ETDEWEB)

    El Afifi, E.M. [Analytical Chemistry and Environmental Control Department, Hot Laboratories and Waste Management Center (HLWMC), Atomic Energy Authority, Post Office No. 13759, Cairo (Egypt); Awwad, N.S. [Analytical Chemistry and Environmental Control Department, Hot Laboratories and Waste Management Center (HLWMC), Atomic Energy Authority, Post Office No. 13759, Cairo (Egypt)], E-mail: nsawwad20@yahoo.com; Hilal, M.A. [Analytical Chemistry and Environmental Control Department, Hot Laboratories and Waste Management Center (HLWMC), Atomic Energy Authority, Post Office No. 13759, Cairo (Egypt)

    2009-01-30

    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 {approx}91 {+-} 3.5, 87 {+-} 4.1 and 90 {+-} 6.2%, respectively.

  8. Sequential chemical treatment of radium species in TENORM waste sludge produced from oil and natural gas production.

    Science.gov (United States)

    El Afifi, E M; Awwad, N S; Hilal, M A

    2009-01-30

    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 approximately 91+/-3.5, 87+/-4.1 and 90+/-6.2%, respectively.

  9. 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)

    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)

  10. 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.

  11. The Natural Activation Ability of Subsurface Media During In-Situ Chemical Oxidation of 1,4-Dioxane

    Science.gov (United States)

    Yan, N.; Brusseau, M. L. L.; Zhong, H.; Li, M.

    2015-12-01

    The ability of soils and sediments to produce in-situ activation of persulfate was investigated for treatment of 1,4-dioxane (dioxane). Experiments were conducted with both batch-reactor and column systems to examine reaction rates and activation mechanisms. Four soils and aquifer sediments were used. ICP-MS, SEM-EDS, and XRD analyses were used to characterize geochemical properties. For the batch experiments, degradation of dioxane was significantly greater in the presence of each of the four subsurface geomedia compared to the controls with no geomedia. This indicates that all four geomedia induced persulfate activation. The use of a binary oxidant system, with the addition of hydrogen peroxide, further enhanced dioxane degradation. It is hypothesized that iron associated with the geomedia is primarily responsible for activation, and that the degree of degradation enhancement relates in part to iron content. For the miscible-displacement experiments, slight retardation and minimal mass loss of persulfate was observed for transport in the column packed with the selected soil. And no dioxane degradation was observed, likely due to the low hydraulic residence time. Conversely, oxidant decomposition, sulfate generation, and dioxane degradation were observed upon injection of persulfate and H2O2. The results of this study indicate that geomedia can induce activation of persulfate to enhance in-situ chemical oxidation applications.

  12. 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.

  13. Effect of the nature the carbon precursor on the physico-chemical characteristics of the resulting activated carbon materials

    International Nuclear Information System (INIS)

    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 N2/77 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 H2 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.

  14. The Nature of the Chemical Process; 1, Symmetry Evolution - Revised Information Theory, Similarity Principle and Ugly Symmetry

    CERN Document Server

    Lin, S K

    2001-01-01

    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. Some examples in chemical physics have been given. Spontaneous processes of all kinds of molecular interactio...

  15. Effects of Cutting Intensity on Soil Physical and Chemical Properties in a Mixed Natural Forest in Southeastern China

    Directory of Open Access Journals (Sweden)

    Xinnian Zhou

    2015-12-01

    Full Text Available The mixed Chinese fir (Cunninghamia lanceolata (Lamb. Hook., Masson’s pine (Pinus massoniana Lamb., and hardwood forest is a major forest type in China and of national and international importance in terms of its provision of both timber and ecosystem services. However, over-harvesting has threatened its long-term productivity and sustainability. We examined the impacts of timber harvesting intensity on soil physical and chemical properties 10 and 15 years after cutting using the research plots established with a randomized block design. We considered five treatments, including clear cutting and low (13.0% removal of growing stock volume, medium (29.1%, high (45.8%, and extra-high (67.1 intensities of selective cutting with non-cutting as the control. The impact on overall soil properties derived from principal component analysis showed increasing with a rise in cutting intensity, and the most critical impact was on soil nutrients, P and K in particular. Soil nutrient loss associated with timber harvesting even at a low cutting intensity could lead to nutrient deficits in this forest although most of the soil physical properties could be recovered under the low and medium intensities of cutting. These results indicate that clear cutting and the selective cutting of extra-high and high intensities should be avoided in this type of forest in the region.

  16. Determination of the mycotoxin moniliformin in cultures of Fusarium subglutinans and in naturally contaminated maize by high-performance liquid chromatography-atmospheric pressure chemical ionization mass spectrometry.

    Science.gov (United States)

    Sewram, V; Nieuwoudt, T W; Marasas, W F; Shephard, G S; Ritieni, A

    1999-07-01

    A LC-MS method employing triethylamine as ion-pairing reagent for the determination of moniliformin in culture material and naturally contaminated maize samples is described. Mass spectrometric detection of moniliformin was accomplished following atmospheric pressure chemical ionization to yield the deprotonated molecular ion [M-H]- at m/z 97. The moniliformin response was found to be linear over the injected range 10 ng to 700 ng and a detection limit of 10 ng was attainable at a signal-to-noise (S/N) ratio of 4. Five South African strains of Fusarium subglutinans were grown on maize kernels and moniliformin extracted with an acetonitrile-water (95:5) mixture. Following sample clean up with reversed-phase (C18) solid-phase extraction cartridges, the extracts were subjected to LC-MS analysis. Triethylamine was used as an ion-pair reagent and found to improve the retention characteristics of moniliformin without any detrimental effects to the instrument. Moniliformin concentrations ranged between 130 mg/kg and 1460 mg/kg culture. Application of this method to naturally contaminated maize samples from Transkei showed that it was capable of measuring moniliformin levels down to 10 micrograms/kg in selected moldy maize cobs. This is the first report on the application of LC-MS to the analysis of moniliformin in cultures of F. subglutinans and in naturally contaminated maize. PMID:10427758

  17. Natural Alkali Shifts to the Methanol Business

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Inner Mongolia Yuanxing Natural Alkali Co., Ltd. (Natural Alkali SZ: 000683) established in 1997 is a large chemical enterprise with new energy as its leading business and natural gas chemicals and natural alkali chemicals as the supplement business.

  18. Chemical Synthesis of Uncommon Natural Bile Acids: The 9α-Hydroxy Derivatives of Chenodeoxycholic and Lithocholic Acids.

    Science.gov (United States)

    Iida, Takashi; Namegawa, Kazunari; Nakane, Naoya; Iida, Kyoko; Hofmann, Alan Frederick; Omura, Kaoru

    2016-09-01

    The chemical synthesis of the 9α-hydroxy derivatives of chenodeoxycholic and lithocholic acids is reported. For initiating the synthesis of the 9α-hydroxy derivative of chenodeoxycholic acid, cholic acid was used; for the synthesis of the 9α-hydroxy derivative of lithocholic acid, deoxycholic acid was used. The principal reactions involved were (1) decarbonylation of conjugated 12-oxo-Δ(9(11))-derivatives using in situ generated monochloroalane (AlH2Cl) prepared from LiAlH4 and AlCl3, (2) epoxidation of the deoxygenated Δ(9(11))-enes using m-chloroperbenzoic acid catalyzed by 4,4'-thiobis-(6-tert-butyl-3-methylphenol), (3) subsequent Markovnikov 9α-hydroxylation of the Δ(9(11))-enes with AlH2Cl, and (4) selective oxidation of the primary hydroxyl group at C-24 in the resulting 3α,9α,24-triol and 3α,7α,9α,24-tetrol to the corresponding C-24 carboxylic acids using sodium chlorite (NaClO2) in the presence of a catalytic amount of 2,2,6,6-tetramethylpiperidine 1-oxyl free radical (TEMPO) and sodium hypochlorite (NaOCl). The (1)H- and (13)C-NMR spectra are reported. The 3α,7α,9α-trihydroxy-5β-cholan-24-oic acid has been reported to be present in the bile of the Asian bear, and its 7-deoxy derivative is likely to be a bacterial metabolite. These bile acids are now available as authentic reference standards, permitting their identification in vertebrate bile acids. PMID:27319285

  19. 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. PMID:22407402

  20. Ability of structurally diverse natural products and synthetic chemicals to induce gene expression mediated by estrogen receptors from various species.

    Science.gov (United States)

    Matthews, J B; Fertuck, K C; Celius, T; Huang, Y-W; Fong, C J; Zacharewski, T R

    2002-10-01

    The ability of 14 structurally diverse estrogenic compounds to induce reporter gene expression mediated by estrogen receptors (ERs) from different species was examined. MCF-7 cells were transiently transfected with a Gal4-regulated luciferase reporter gene (17m5-G-Luc) and Gal4-ER chimeric receptors containing the D, E and F domains of the human alpha (Gal4-hERalphadef), mouse alpha (Gal4-mERalphadef), mouse beta (Gal4-mERbetadef), chicken (Gal4-cERalphadef), green anole (Gal4-aERalphadef), Xenopus (Gal4-xERdef) or rainbow trout alpha ERs (Gal4-rtERalphadef). The efficacy of 17beta-estradiol (E2) in inducing reporter gene expression was similar among the different constructs overall, with EC(50) values ranging from 0.05 to 0.7nM. However, Gal4-rtERalphadef had an EC(50) value at 37 degrees C of 28nM, though at 20 degrees C an EC(50) value of 1nM was observed. Despite a similar response to E2 treatment among the ERs, many differences were observed in the magnitude of the response to other structurally diverse chemicals. For example, coumestrol induced Gal4-mERbetadef- and Gal4-aERdef-mediated reporter gene expression 164- and 8-fold greater, respectively, than mediated with the other Gal4-ERs. As well, in contrast to results with other Gal4-ERs, alpha-zearalenol consistently induced Gal4-rtERalphadef-mediated reporter gene activity at lower concentrations than did E2. Overall, the results demonstrate that selected estrogenic compounds exhibit a differential ability to induce reporter gene activity mediated by ERs from different vertebrate species. These data also highlight the importance of incubation temperature when examining rtERalpha-mediated activity. PMID:12477484

  1. Extensor pollicis brevis tendon can hyperextend thumb interphalangeal joint in absence of extensor pollicis longus: Case report and review of the literature

    Science.gov (United States)

    Strauch, Robert J; Strauch, Carolyn B

    2016-01-01

    We are reporting a case of extensor pollicis longus tendon rupture which did not require tendon transfer owing to the ability of the intact extensor pollicis brevis (EPB) to fully hyperextend the thumb interphalangeal joint. The thumb metacarpophalangeal joint was also able to be fully actively extended by the EPB. Previous anatomical studies have demonstrated that the insertional anatomy of the EPB tendon is highly variable and sometimes inserts onto the extensor hood and distal phalanx, which is likely the mechanism by which our patient was able to fully extend the thumb interphalangeal joint. Despite the potential for the EPB to extend the IP joint of the thumb, virtually all previously reported cases of extensor pollicis longus (EPL) tendon rupture had deficits of thumb IP extension requiring tendon transfer. This case highlights the potential ability of the EPB tendon to completely substitute for the function of the EPL tendon in providing thumb IP joint extension. PMID:27458556

  2. Extensor pollicis brevis tendon can hyperextend thumb interphalangeal joint in absence of extensor pollicis longus: Case report and review of the literature.

    Science.gov (United States)

    Strauch, Robert J; Strauch, Carolyn B

    2016-07-18

    We are reporting a case of extensor pollicis longus tendon rupture which did not require tendon transfer owing to the ability of the intact extensor pollicis brevis (EPB) to fully hyperextend the thumb interphalangeal joint. The thumb metacarpophalangeal joint was also able to be fully actively extended by the EPB. Previous anatomical studies have demonstrated that the insertional anatomy of the EPB tendon is highly variable and sometimes inserts onto the extensor hood and distal phalanx, which is likely the mechanism by which our patient was able to fully extend the thumb interphalangeal joint. Despite the potential for the EPB to extend the IP joint of the thumb, virtually all previously reported cases of extensor pollicis longus (EPL) tendon rupture had deficits of thumb IP extension requiring tendon transfer. This case highlights the potential ability of the EPB tendon to completely substitute for the function of the EPL tendon in providing thumb IP joint extension. PMID:27458556

  3. Spectrum of Ultrasound Pathologies of Achilles Tendon, Plantar Aponeurosis and Flexor Digiti Brevis Tendon Heel Entheses in Patients with Clinically Suspected Enthesitis

    International Nuclear Information System (INIS)

    Enthesitis is considered a characteristic presentation of the second most common group of rheumatoid disorders, i.e. spondyloarthropathies (SpAs), particularly peripheral spondyloarthropathies. At the initial stages, enthesitis may be the only symptom of SpA, particularly in patients lacking the HLA-B27 receptor. In light of diagnostic difficulties with detecting enthesitis in clinical examinations and laboratory investigations, many studies point out the high specificity of imaging studies, and particularly ultrasonography. A total of 20% Achilles tendon entheses, 45% plantar aponeurosis entheses and 89.5% of flexor digiti brevis tendon entheses were unremarkable. In the remaining cases, the presentation of pathological lesions was not specific to enthesitis and might more likely correspond to degeneration or microinjuries of the entheses, beside the most obvious cases of achillobursitis or Kager’s fat pad inflammation. The studies demonstrated that ultrasound scans rarely confirm the clinical diagnosis of enthesitis

  4. ["The Society for letters and natural science" The young Ole H. Mynster and the chemical revolution around 1800].

    Science.gov (United States)

    Hansen, Sven Erik

    2015-01-01

    Ole H. Mynster (1772-1818) was a stepson of the leading physician at the Royal Frederik Hospital in Copenhagen. At an early age he became fond of zoology and mineralogy. He created "societies" in Enlightenment-style for boys and young people with lectures and collections. Later on a circle of talented young students, scientists and poets met in his small room at the hospital. Some of them with Ole Mynster as the head set up a modern scientific journal, Physicalsk, oeconomisk og medicochirurgisk Bibliotek for Danmark og Norge which encouraged the introduction of antiphlogistic chemistry. Ole Mynster became physician at the Royal Frederik Hospital and lecturer in clinical pharmacology. He wrote the first book in Danish on pharmacology based upon chemistry. In their memoirs, prominent members of his circle have told about him, and his son F.L. Mynster has written a draft for a biography. An overview of the activities within natural science and medicine of the young Ole Hieronymus Mynster is presented.

  5. 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.

  6. The time-variant nature of catchment travel time pdf's: implications for the intepretation of hydro-chemical signals

    Science.gov (United States)

    Benettin, P.; Botter, G.; Bertuzzo, E.; Rinaldo, A.

    2012-12-01

    Catchments are highly dynamical systems forced by stochastic precipitation, and characterized by time-variable transpiration rates and discharges. Despite this, streamflow hydrochemical signals have been frequently interpreted through stationary convolutions between rainfall concentrations and time-invariant transfer functions, on the basis of which the properties of the travel time pdf were inferred. In this contribution we define the intrinsic dynamical nature of travel and residence time distributions, which explains the variability of the mechanisms through which catchments retain and release old and event water, transporting solutes and pollutants to receiving water bodies. General expressions for travel and residence time pdf's are derived as a function of the underlying rainfall-soil-vegetation dynamics and the mixing processes occurring along streamflow production and plant uptake. The work highlights the dependence of water/solute travel times on key eco-hydrological processes (especially transpiration and uptake), and investigates the impact of the time variance in terms of the identification of travel time pdfs and catchment functioning. This is done by means of numerical experiments, and through real-world applications based on the analysis of stream concentrations of chlorides/pesticides in agricultural catchments.

  7. Biological and chemical evaluation of sewage water pollution in the Rietvlei nature reserve wetland area, South Africa

    International Nuclear Information System (INIS)

    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

  8. Synthetic fluid inclusions in natural quartz. IV. Chemical analyses of fluid inclusions by SEM/EDA: Evaluation of method

    Energy Technology Data Exchange (ETDEWEB)

    Haynes, F.M. (Univ. of Michigan, Ann Arbor (USA)); Sterner, S.M.; Bodnar, R.J. (Virginia Polytechnic Institute, Blacksburg (USA))

    1988-05-01

    The compositions of individual synthetic fluid inclusions in the systems NaCl-KCl, NaCl-CaCl{sub 2} and NaCl-KCl-CaCl{sub 2} have been semi-quantitatively determined by energy dispersive analysis of precipitates produced during thermal decrepitation. Inclusions containing known mixtures of 20 wt.% total salinity were synthesized by healing fractures in natural quartz at 600-700{degree}C and 5-7 kbars for 7-10 days. The two-phase, daughter-free inclusions homogenized at 170-250{degree}C, began to decrepitate after about 100{degree} of overheating and by 360-420{degree}C a significant number of decrepitates had formed on the polished surface. Peak heights generated by EDA (raster mode) of these decrepitates were standardized using both single and mixed salt standards evaporated to dryness in a vacuum. Although the mixed salt standards better approximated the decrepitate compositions, difficulties were encountered in producing micron-scale homogeneity and the single salts yielded more reliable results.

  9. Gene expression in Florida red tide dinoflagellate Karenia brevis: analysis of an expressed sequence tag library and development of DNA microarray.

    Science.gov (United States)

    Lidie, Kristy B; Ryan, James C; Barbier, Michele; Van Dolah, Frances M

    2005-01-01

    Karenia brevis (Davis) is the dinoflagellate responsible for nearly annual red tides in the Gulf of Mexico. Although the mechanisms regulating the growth and toxicity of this problematic organism are of considerable interest, little information is available on its molecular biology. We therefore constructed a complementary DNA library from which to gain insight into its expressed genome and to develop tools for studying its gene expression. Large-scale sequencing yielded 7001 high-quality expressed sequence tags (ESTs), which clustered into 5280 unique gene groups. The vast majority of genes expressed fell into a low-abundance class, with the highest expressed gene accounting for only 1% of the total ESTs. Approximately 29% of genes were found to have similarity to known sequences in other organisms after BLAST similarity comparisons to the GenBank public protein database using a cutoff of P < 10e(-4). We identified for the first time in a dinoflagellate a suite of conserved eukaryotic genes involved in cell cycle control, intracellular signaling, and the transcription and translation machinery. At least 40% of gene clusters displayed single nucleotide polymorphisms, suggesting the presence of multiple gene copies. The average GC content of ESTs was 51%, with a slight preference for G or C in the third codon position (53.5%). The ESTs were used to develop an oligonucleotide microarray containing 4629 unique features and 3462 replicate probes. Microarray labeling has been optimized, and the microarray has been validated for probe specificity and reproducibility. This is the first information to be developed on the expressed genome of K. brevis and provides the basis from which to begin functional genomic studies on this harmful algal bloom species. PMID:15976935

  10. A Two-stage pH and Temperature Control with Substrate Feeding Strategy for Production of Gamma-aminobutyric Acid by Lactobacillus brevis CGMCC 1306

    Institute of Scientific and Technical Information of China (English)

    彭春龙; 黄俊; 胡升; 赵伟睿; 姚善泾; 梅乐和

    2013-01-01

    Methods to optimize the production of gamma-aminobutyric acid (GABA) by Lactobacillus brevis CGMCC 1306 were investigated. Results indicated that cell growth was maximal at pH 5.0, while pH 4.5 was pref-erable to GABA formation. The optimal temperature for cell growth (35 °C) was lower than that for GABA forma-tion (40 °C). In a two-stage pH and temperature control fermentation, cultures were maintained at pH 5.0 and 35 °C for 32 h, then adjusted to pH 4.5 and 40 °C, GABA production increased remarkably and reached 474.79 mmol·L-1 at 72 h, while it was 398.63 mmol·L-1 with one stage pH and temperature control process, in which cultivation con-ditions were constantly controlled at pH 5.0 and 35 °C. In order to avoid the inhibition of cell growth at higher L-monosodium glutamate (L-MSG) concentrations, the two-stage control fermentation with substrate feeding strat-egy was applied to GABA production, with 106.87 mmol (20 g) L-MSG supplemented into the shaking-flask at 32 h and 56 h post-inoculation separately. The GABA concentration reached 526.33 mmol·L-1 at 72 h with the fer-mentation volume increased by 38%. These results will provide primary data to realize large-scale production of GABA by L. brevis CGMCC 1306.

  11. Coyote (Canis latrans) and domestic dog (Canis familiaris) mortality and morbidity due to a Karenia brevis red tide in the Gulf of Mexico.

    Science.gov (United States)

    Castle, Kevin T; Flewelling, Leanne J; Bryan, John; Kramer, Adam; Lindsay, James; Nevada, Cheyenne; Stablein, Wade; Wong, David; Landsberg, Jan H

    2013-10-01

    In October 2009, during a Karenia brevis red tide along the Texas coast, millions of dead fish washed ashore along the 113-km length of Padre Island National Seashore (PAIS). Between November 2009 and January 2010, at least 12 coyotes (Canis latrans) and three domestic dogs (Canis familiaris) died or were euthanized at PAIS or local veterinary clinics because of illness suspected to be related to the red tide. Another red tide event occurred during autumn 2011 and, although fewer dead fish were observed relative to the 2009 event, coyotes again were affected. Staff at PAIS submitted carcasses of four coyotes and one domestic dog from November 2009 to February 2010 and six coyotes from October to November 2011 for necropsy and ancillary testing. High levels of brevetoxins (PbTxs) were measured by enzyme-linked immunosorbent assay in seven of the coyotes and the dog, with concentrations up to 634 ng PbTx-3 eq/g in stomach contents, 545 ng PbTx-3 eq/g in liver, 195 ng PbTx-3 eq/g in kidney, and 106 ng PbTx-3 eq/mL in urine samples. Based on red tide presence, clinical signs, and postmortem findings, brevetoxicosis caused by presumptive ingestion of toxic dead fish was the likely cause of canid deaths at PAIS. These findings represent the first confirmed report of terrestrial mammalian wildlife mortalities related to a K. brevis bloom. The implications for red tide impacts on terrestrial wildlife populations are a potentially significant but relatively undocumented phenomenon.

  12. 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 pesticide concentrations in water from POCIS deployed in stagnant and turbulent environmental systems without correction for NOM.

  13. Applied Anatomy of the Repair of the First Metatarsal Transverse Ligament Utilizing Tendon Extensor Hallucis Brevis%?母短伸肌腱修复第一跖骨深横韧带的应用解剖

    Institute of Scientific and Technical Information of China (English)

    王谦军; 孙海燕; 王英胜

    2013-01-01

    目的:为?母短伸肌腱转位修复第一跖骨深横韧带提供解剖学基础。方法对48例新鲜尸体足和足趾移植再造手指手术55足?母短伸肌进行解剖、测量。利用?母短伸肌腱修复第一跖骨深横韧带。结果?母短伸肌及腱全长,男性(14.10±0.77)cm,女性(12.89±0.38)cm;肌腱长度,男性(9.40±0.51)cm,女性(8.59±0.25)cm;肌腱厚度(1.10±0.08)mm;宽度(3.90±0.12)mm,其长度足能成双股连结于第一跖骨头与第三跖骨头之间。结论?母短伸肌腱在长度、厚度、宽度等方面完全能够用来修复第一跖骨深横韧带。%Objective To offer anatomy basis for displacing the tendon extensor hallucis brevis to repair metatarsal transverse ligament .Methods Dissect and measure the muscular extensor hallucis brevis of 48 cases of corpse feet and 55 feet of 49 patients of toe-to finger transfer to repair metatarsal transverse ligament with tendon extensor hallucis brevis.Results The length of musculus and tendon extensor hallucis brevis:male (14.10 ±0.77) cm,female (12.89 ±0.38)cm;the length of musculus extensor hallucis brevis:male (4.70 ±0.26)cm,female (4.30 ±0.13)cm;the length of tendon extensor hallucis brevis:male (9.40 ±0.51)cm,female (8.59 ±0.25)cm;The thickness of the tendon extensor hallucis brevis:(1.10 ±0.08)mm;The breadth of the tendon extensor hallucis brevis:(3.90 ±0.12) mm;The tendon was long enough linking the first metatarsal bone head and the third with two strands .Conclusion Ten-don extensor hallucis brevis was completely used to repair metatarsal transverse ligament in respects of length ,thickness and breadth .

  14. Interim report task 2: performance testing - task 2.4: natural mineral analog studies physical and chemical characteristics of brannerite in natural systems to Lawrence Livermore National Laboratory under contract B345772

    Energy Technology Data Exchange (ETDEWEB)

    Lumpkin, G R; Colella, M; Leung, S H F

    2000-04-30

    To investigate the long-term alteration behavior of brannerite, we have undertaken a study of 13 natural samples from various geological environments, including granites, granitic pegmatites, quartz veins, and placer deposits. Literature data and U-Th-Pb chemical dating carried out in this work indicate that the samples range in age from approximately 20 Ma to 1580 Ma. Where independent age data or estimates are available for comparison, the U-Th-Pb chemical ages are in reasonable agreement for the younger samples, but the older samples tend to show evidence for Pb loss (up to about 80%), a common feature of metamict Nb, Ta, and Ti oxide minerals. Our results show that many of the samples exhibit only minor alteration, usually within small patches, microfractures, or around the rims of the brannerite crystals. Other samples consist of variable amounts of unaltered and altered brannerite. Heavily altered samples may contain anatase and thorite as fine-grained alteration products. Certain samples exhibited fracturing of the associated rock matrix or mineral phase in the immediate vicinity of the brannerite grains. These fractures contain U bearing material and indicate that some U migrated locally from the source brannerite.

  15. Experimental device for chemical osmosis measurement on natural clay-rock samples maintained at in situ conditions: implications for formation pressure interpretations.

    Science.gov (United States)

    Rousseau-Gueutin, Pauline; de Greef, Vincent; Gonçalvès, Julio; Violette, Sophie; Chanchole, Serge

    2009-09-01

    In order to characterize the so-called coupled processes occurring in compacted clay rocks, the coupling coefficients must be identified. For this purpose, an original device which allows such measurement for undisturbed (natural) samples in their in situ conditions was developed. The present experimental device minimizes the fluid leaks improving the accuracy of the coupling parameter determination. Three chemical osmotic tests were performed on a cylindrical sample of Callovo-Oxfordian argilite. Room temperature variations during the chemical osmosis experiments required the implementation of temperature effects in the numerical model used for the interpretations. These variations offered the opportunity of an alternative method to estimate the compressibility of the fluid in the circuit connected to a measurement chamber located in the center of the sample. An osmotic efficiency of almost 0.2 for a concentration of 0.094 mol L(-1) is obtained for the Callovo-Oxfordian argilite. This value would explain only some part (approximately 0.10-0.15 MPa) of the overpressures (0.5-0.6 MPa) relative to the surrounding reservoirs measured in this formation. Others processes, such as thermo-osmosis, hydrodynamic boundary condition changes due to climate variations or creep behavior of the shale, could explain the remainder of the overpressures. PMID:19527907

  16. Utilization of wastewater originated from naturally fermented virgin coconut oil manufacturing process for bioextract production: physico-chemical and microbial evolution.

    Science.gov (United States)

    Tripetchkul, Sudarut; Kusuwanwichid, Sasithorn; Koonsrisuk, Songpon; Akeprathumchai, Saengchai

    2010-08-01

    Production of virgin coconut oil via natural fermentation has led to large amount of wastes being generated, i.e., coconut pulp and wastewater containing coconut crème. Objective of this study is to gain more insight into the feasibility of utilization of such wastes as raw materials together with several types of wastes such as fish waste and/or pineapple peel for bioextract production. Chemical, physico-chemical and biological changes including phytotoxicity of the fermented mixture were closely monitored. Physical observation suggested that fermentation of bioextract obtained with fish waste appeared to be complete within the first month of fermentation while bioextract obtained using pineapple waste seemed to be complete after 8 months post-fermentation. Fermentation broth is of blackish color with alcoholic as well as acidic odour with no gas bubble and/or yeast film present on top of the surface. During the whole fermentation interval, several attributes of both bioextracts, e.g., pH, chemical oxygen demand (COD) and organic acids, were statistically different. Further, the total bacteria and lactic acid bacteria present in pineapple bioextract were statistically higher than those of the fish bioextract (ppineapple bioextracts, respectively. In addition, qualities of both bioextracts conformed well with those specified by the Thai standard for liquid biofertilizer after 1 month fermentation. Results further showed that wastewater derived from virgin coconut oil manufacturing process could effectively be employed together with other types of wastes such as fish waste and pineapple peel for bioextract production. However, for the best bioextract quality, fermentation should be carefully planned since over fermentation led to bioextract of low qualities. PMID:20362440

  17. Effects of natural and chemical stressors on Enchytraeus albidus: can oxidative stress parameters be used as fast screening tools for the assessment of different stress impacts in soils?

    Science.gov (United States)

    Howcroft, C F; Amorim, M J B; Gravato, C; Guilhermino, L; Soares, A M V M

    2009-02-01

    Enchytraeids are important organisms of the soil biocenosis. They improve the soil pore structure and the degradation of organic matter. These organisms are used in standardized testing, using survival and reproduction (6 weeks) as endpoints. The use of biomarkers, linked to ecologically relevant alterations at higher levels of biological organization, is a promising tool for Environmental Risk Assessment. Here, enchytraeids were exposed for different time periods (two days and three weeks) to different soils (OECD artificial soil, different compositions in its organic matter, clay or pH value, and LUFA 2.2 natural soil) and different chemicals (Phenmedipham and copper). The main question addressed in the present study was if the effects of chemicals and different soil properties are preceded by alterations at the sub-cellular level, and if these endpoints may be used reliantly as faster screening tools for the assessment of different stress conditions in soils. The parameters measured in E. albidus whole body were: lipid peroxidation (LPO), total glutathione (TG), as well as the enzymatic activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione S-transferase (GST). The results showed that biomarker responses in E. albidus were significantly affected by the soil type (GST, CAT, GPx, GR and LPO) and the duration of exposure in OECD artificial soil (GST, GPx, GR, CAT and LPO) but not in LUFA 2.2 natural soil. For the abiotic factors studied, after 2 days, low pH decreased significantly the TG levels and the activities of CAT and GR,and low OM also significantly decreased CAT and GR activities. After 3 weeks, differences in soil properties caused a decrease in GR and GPx activities, whereas increased GST activity was observed due to low organic matter and pH. Copper significantly increased the activities of CAT, GPx and GR, and decreased the activity of GST after 2 days as well as inscreasing

  18. Hygienic and microbiological influences exerted on natural water biotopes by algae and the growth of water plants. 2. Communication: improvement of the chemical and bacteriological water quality by the natural growth of aquatic plants (author's transl)

    Energy Technology Data Exchange (ETDEWEB)

    Graef, W.; Kersch, D.; Pawlofsky, C.M.

    1981-12-01

    For a natural pond, whose waters are used for recreational purposes (swimming) and are subject to waste water inflow, the biological purifying function of a zone overgrown with reeds and aquatic plants was ascertained by means of chemical and bacteriological water quality parameters. In the years from 1975 to 1980 the contents of ammonia, nitrites, nitrates, phosphates and chlorides as well as the colony counts (CFU/ml), the coli titres and the content of fruiting myxobacteria were determined from water samples, both during the lush-growth summer period and the low-growth winter season. The location of the 6 sampling points systematically extended from the sewage outlet via the tributary ditch, in front of and behind the natural growth zone as far as the swimming waters. The test series showed - that in the tributary ditch and especially during the passage through the upper water zone densely overgrown with aquatic plants, the proportion of degradable nitrogen compounds and phosphates is distinctly reduced beyond the extent of reduction by dilution processes, - that the colony counts in the effluent water as well as the content of E. coli and of the fruiting myxobacteria, which act as indirect faecal indicator, are also reduced considerably, - that the biological purifying of the vegetation zone is definitely higher in summer than during the low-growth winter months. From this the conclusion can be drawn that for maintaining and furthering an adequate water quality of recreational waters compromised by waste water, the preservation of the naturally growing aquatic plants both in the water itself and on the banks is absolutely necessary.

  19. 短乳杆菌JH-1体外降胆固醇机理的初步探讨%Mechanism of Cholesterol-Degrading Activity of Lactobacillus brevis JH-1 in vitro

    Institute of Scientific and Technical Information of China (English)

    姜华; 陆兆新

    2015-01-01

    [目的]为了初步阐明短乳杆菌Lactobacillus brevis JH-1体外降胆固醇机理.[方法]分析乳酸菌降胆固醇作用的3种可能的机理(同化作用、共沉淀作用和掺入细胞膜).[结果] Lactobacillus brevis JH-1体外降胆固醇与同化作用和掺入细胞膜有关.[结论]初步判定短乳杆菌JH-1体处降胆固醇是同化作用和掺入细胞膜共同作用的结果.

  20. 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)

    Measurements of aerosol were made in August and October 2001, and January 2002, at Dunhuang, China (40o00'N, 94o30'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

  1. Multi-Sensor Approach for the Monitoring of Halitosis Treatment via Lactobacillus brevis (CD2)—Containing Lozenges—A Randomized, Double-Blind Placebo-Controlled Clinical Trial

    OpenAIRE

    Enrico Marchetti; Simona Tecco; Marco Santonico; Chiara Vernile; Daniele Ciciarelli; Ester Tarantino; Giuseppe Marzo; Giorgio Pennazza

    2015-01-01

    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 trea...

  2. Influence of meteorology and anthropogenic pollution on chemical flux divergence of the NO-NO2-O3 triad above and within a natural grassland canopy

    Directory of Open Access Journals (Sweden)

    D. Plake

    2014-07-01

    Full Text Available The detailed understanding of surface–atmosphere exchange of reactive trace gas species is a crucial precondition for reliable modeling of processes in atmospheric chemistry. Plant canopies significantly impact the atmospheric budget of trace gases. In the past, many studies focused on taller forest canopies or crops, where the bulk plant material is concentrated in the uppermost canopy layer. However, within grasslands, a land-cover class that globally covers vast terrestrial areas, the canopy structure is fundamentally different, as the main biomass is concentrated in the lowest canopy part. This has obvious implications for aerodynamic in-canopy transport, and consequently also impacts on global budgets of key species in atmospheric chemistry such as nitric oxide (NO, nitrogen dioxide (NO2 and ozone (O3. This study presents for the first time a~comprehensive data set of directly measured in-canopy transport times and aerodynamic resistances, chemical timescales, Damköhler numbers, trace gas and micrometeorological measurements for a natural grassland canopy (canopy height = 0.6 m. Special attention is paid to the impact of contrasting meteorological and air chemical conditions on in-canopy transport and chemical flux divergence. Our results show that the grassland canopy is decoupled throughout the day. In the lower canopy, the measured transport times are fastest during nighttime, which is due to convection during nighttime and stable stratification during daytime in this layer. The inverse was found in the layers above. During periods of low wind speed and high NOx (NO+NO2 levels, the effect of canopy decoupling on trace gas transport was found especially distinct. The aerodynamic resistance in the lower canopy (0.04–0.2 m was around 1000 s m−1, thus as high as values from literature representing the lowest meter of an Amazonian rain forest canopy. The aerodynamic resistance representing the bulk canopy was found to be more than 3

  3. Influence of meteorology and anthropogenic pollution on chemical flux divergence of the NO-NO2-O3 triad above and within a natural grassland canopy

    Science.gov (United States)

    Plake, D.; Sörgel, M.; Stella, P.; Held, A.; Trebs, I.

    2015-02-01

    The detailed understanding of surface-atmosphere exchange fluxes of reactive trace gases is a crucial precondition for reliable modelling of processes in atmospheric chemistry. Plant canopies significantly impact the atmospheric budget of trace gases. In the past, many studies focused on taller forest canopies or crops, where the bulk plant material is concentrated in the uppermost canopy layer. However, within grasslands, a land-cover class that globally covers vast terrestrial areas, the canopy structure is fundamentally different, as the main biomass is concentrated in the lowest part of the canopy. This has obvious implications for aerodynamic in-canopy transport, and consequently also impacts on global budgets of key species in atmospheric chemistry such as nitric oxide (NO), nitrogen dioxide (NO2) and ozone (O3). This study presents for the first time a comprehensive data set of directly measured in-canopy transport times and aerodynamic resistances, chemical timescales, Damköhler numbers, trace gas and micrometeorological measurements for a natural grassland canopy (canopy height = 0.6 m). Special attention is paid to the impact of contrasting meteorological and air chemical conditions on in-canopy transport and chemical flux divergence. Our results show that the grassland canopy is decoupled throughout the day. In the lowermost canopy layer, the measured transport times are fastest during nighttime, which is due to convection during nighttime and a stable stratification during daytime in this layer. The inverse was found in the layers above. During periods of low wind speed and high NOx (NO+NO2) levels, the effect of canopy decoupling on trace gas transport was found to be especially distinct. The aerodynamic resistance in the lowermost canopy layer (0.04-0.2 m) was around 1000 s m-1, which is as high as values determined previously for the lowest metre of an Amazonian rain forest canopy. The aerodynamic resistance representing the bulk canopy was found to

  4. Chemical and microbiological characteristics of sugar cane silages treated with microbial inoculants Características químicas e microbiológicas de silagens de cana-de-açúcar tratada com inoculantes microbianos

    OpenAIRE

    Carla Luiza da Silva Ávila; Alexandre Rocha Valeriano; José Cardoso Pinto; Henrique César Pereira Figueiredo; Adauton Vilela Rezende; Rosane Freitas Schwan

    2010-01-01

    The aim of this research was to evaluate the effect of microbial additives containing heterofermentative or homofermentative bacteria on the chemical and microbiological characteristics of sugar cane (Saccharum spp) silages. Sugar cane was inoculated with Lactobacillus plantarum, L. paracasei, L. brevis or L. buchneri previously isolated from sugar cane silages or commercial inoculants containing L. buchneri or L. plantarum. Silages were produced in laboratory silos (10 × 60 cm PVC tubes...

  5. A natural orbital analysis of the long range behavior of chemical bonding and van der Waals interaction in singlet H2: the issue of zero natural orbital occupation numbers.

    Science.gov (United States)

    Sheng, X W; Mentel, Ł M; Gritsenko, O V; Baerends, E J

    2013-04-28

    This paper gives a natural orbital (NO) based analysis of the van der Waals interaction in (singlet) H2 at long distance. The van der Waals interaction, even if not leading to a distinct van der Waals well, affects the shape of the interaction potential in the van der Waals distance range of 5-9 bohrs and can be clearly distinguished from chemical bonding effects. In the NO basis the van der Waals interaction can be quantitatively covered with, apart from the ground state configurations (1σ(g))(2) and (1σ(u))(2), just the 4 configurations (2σ(g))(2) and (2σ(u))(2), and (1π(u))(2) and (1π(g))(2). The physics of the dispersion interaction requires and explains the peculiar relatively large positive CI coefficients of the doubly excited electron configurations (2σ(u))(2) and (1π(g))(2) (the occupancy amplitudes of the 2σ(u) and 1π(gx, y) NOs) in the distance range 5-9 bohrs, which have been observed before by Cioslowski and Pernal [Chem. Phys. Lett. 430, 188 (2006)]. We show that such positive occupancy amplitudes do not necessarily lead to the existence of zero occupation numbers at some H-H distances.

  6. 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.

  7. Deciphering the "chemical" nature of the exotic isotopes of Hydrogen by the MC-QTAIM analysis: Positive Muon and Muonic Helium as new members of The Periodic Table

    CERN Document Server

    Goli, Mohammad

    2013-01-01

    This report is a primarily survey on the chemical nature of the positively charged muon and muonic Helium (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. To perform the analysis, the non-Born-Oppenhiemer (non-BO) ab initio methodology termed the fully variational multi-component molecular orbital method (FV-MC_MO) is used to deduce non-BO wavefunctions of various three and four-component molecular systems, as isotopomers of the orthodox hydrogen molecule, replacing proton(s) with muon, deuterium, tritium and muonic Helium. The derived three-component non-BO wavefunctions then are used for the "atoms in molecules" analysis within the context of the MC-QTAIM framework. Using various asymmetric isotopomers of hydrogen molecule, it is demonstrated that both the positively charged muon and muonic Helium are capable to form atoms in molecules in the considered molecules; thus, they reta...

  8. The chemical nature of the carbon-14- labelled organic matter released into soil from growing wheat roots. Effects of soil micro-organisms

    International Nuclear Information System (INIS)

    Individual wheat plants were grown in a sandy soil under an atmosphere of 14CO2 for 21 days with the plant roots maintained under sterile or non-sterile conditions. A comparison has been made of the chemical nature of the 14C-labelled organic matter present in root-free soil from the sterile and non-sterile treatments, based on solubility, molecular size and ion-exchange chromatography of soil extracts and acid hydrolysates of whole soil. There was little difference between sterile and non-sterile soils for the values from any of these determinations. It is proposed that a major part of the organic 14C present in soils from both treatments resulted from autolysis of root tissue, particularly in localized zones where low water availability may have limited microbial decomposition of sugars and amino acids released from the roots. About 15% of the 14C in both soil treatments was present in humic acid fractions with a molecular weight, estimated from ultrafiltration of >5X104. These experiments show that there can be a significant formation of soil organic matter during active root growth, much of it directly from root tissue without the intervention of soil microflora or microfauna. Such reactions would be important in nutrient cycling in permanent pastures and forests, and in the interchange of nutrients in grass/legume associations. (author)

  9. Fertilization Effects on the Chemical Composition and In vitro Organic Matter Digestibility of Semi-natural Meadows as Predicted by NIR Spectrometry

    Directory of Open Access Journals (Sweden)

    Laura M. DALE

    2013-05-01

    Full Text Available Management of livestock grazing in highly-productive mountain meadows is an important aspect for the economic viability and the environmental impact of a grassland-based farm. The main aim of this study was to build near infrared models to determine the chemical composition and in vitro organic matter digestibility of Romanian meadow forages. The treatments were organic and mineral fertilizer combinations, and forage samples were obtained from three fertilization experiments conducted in the Apuseni Mountains; these samples were analysed using classical and NIR methods. The samples were scanned in the NIR wavelength band. The CRA-W Gembloux ‘local’ calibration models were validated with Romanian meadow forages and then used in order to predict the forage quality of samples. A second objective of the study was to determine the effects of fertilization on forage quality. The results showed a decrease in crude protein content from the NPK treatment (150:75:75, which can be explained by a reduction of Fabaceae plants with this treatment from 17.25% of the populations in the control (semi-natural meadow not fertilized to 6.25% in the fertilized plots. The decrease in protein content and in vitro organic matter digestibility was related to a reduced Fabaceae presence. Our recommendation is to use mineral fertilization with NPK doses less than 100:50:50 to improve meadow productivity; meanwhile organic fertilization can also be used to complement and maintain biodiversity and forage quality.

  10. 短乳杆菌谷氨酸脱羧酶的生物信息学分析%Bioinformatics Analysis of Glutamate Decarboxylase from Lactobacillus brevis

    Institute of Scientific and Technical Information of China (English)

    齐育平; 孙蕾; 刘琴英; 蒋冬花

    2014-01-01

    以短乳杆菌(Lactobacillus brevis)Lb-2菌株cDNA为模板克隆了谷氨酸脱羧酶(Glutamate decarboxylase,GAD)基因.采用在线分析工具及相应软件分析预测了GAD基因核苷酸和氨基酸序列的组成、理化性质、信号肽以及高级结构等,并构建系统发育树.该基因序列全长1 407 bp,为一个完整的阅读框,编码468个氨基酸.GAD相对分子量理论预测值和等电点分别是53 517.8 u和5.42,没有跨膜区,没有其他亚细胞定位序列,为亲水性蛋白,与植物乳杆菌(Lactobacillus plantarum)和德氏乳酸杆菌(Lactobacillus delbrueckii)的GAD进化关系最近.

  11. Partial Purification and Characterization of a Bacteriocin DT24 Produced by Probiotic Vaginal Lactobacillus brevis DT24 and Determination of its Anti-Uropathogenic Escherichia coli Potential.

    Science.gov (United States)

    Trivedi, Disha; Jena, Prasant Kumar; Patel, Jignesh Kumar; Seshadri, Sriram

    2013-06-01

    The emergence of antibiotic resistance has increased the interest for finding new antimicrobials in the past decade. Probiotic Lactic acid bacteria producing antimicrobial proteins like bacteriocin can be excellent agents for development as novel therapeutic agents and complement to conventional antibiotic therapy. Uropathogenic Escherichia coli, most causative agent of Urinary tract infection, has developed resistance to various antibiotics. In the present investigation, antibacterial substance like bacteriocin (Bacteriocin DT24) produced by probiotic Lactobacillus brevis DT24 from vaginal sample of healthy Indian woman was partially purified and characterized. It was efficiently working against various pathogens, that is, Uropathogenic E. coli, Enterococcus faecium, Enterococcus faecalis and Staphylococcus aureus. The antimicrobial peptide was relatively heat resistant and also active over a broad range of pH 2-10. It has been partially purified by ammonium sulfate precipitation and gel filtration chromatography and checked on reverse-phase high-performance liquid chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of bacteriocin DT24 was approximately 7-kDa protein. The peptide is inactivated by proteolytic enzymes, trypsin and lipase but not when treated with catalase, α-amylase and pepsin. It showed bacteriostatic mode of action against uropathogenic E. coli. Such characteristics indicate that this bacteriocin-producing probiotic may be a potential candidate for alternative agents to control urinary tract infections and other pathogens. PMID:26782739

  12. Annulotrema (Monogenea: Dactylogyridae) from Hydrocynus brevis (Characiformes: Alestidae) in Senegal, with descriptions of two new species and remarks on Annulotrema pikei.

    Science.gov (United States)

    Řehulková, Eva; Musilová, Naďa; Gelnar, Milan

    2014-09-01

    Two new species of Annulotrema Paperna & Thurston, 1969 were collected from the gills of the African tiger fish, Hydrocynus brevis, from the Gambia River basin in the Niokolo-Koba National Park, Senegal. Annulotrema besalis n. sp. is characterized by having a male copulatory organ (MCO) composed of an arcuate copulatory tube articulated to an eight-shaped accessory piece with terminal claw. The new species resembles Annulotrema pikei (Price, Peebles & Bamford, 1969) in having morphologically similar types of haptoral sclerites and MCO. As a result of the differential diagnosis made for A. besalis n. sp., new information on taxonomically important features of A. pikei is provided based on illustrations of the sclerotized parts of the holotype from Hydrocynus vittatus. The report of A. pikei on the gills of Hydrocynus forskahlii by Paperna in 1979 is shown to be erroneous. Annulotrema uncata n. sp. is similar to Annulotrema alestesimberi Paperna, 1973 in its possession of a coiled copulatory tube with about two and a half rings. Features distinguishing the new species include the sharply curved shaft of the ventral anchor, the base of the copulatory tube extending to a sock-like structure and a leech-shaped vagina. The necessity of emending the generic diagnosis of Annulotrema is briefly discussed. PMID:24972586

  13. A Review of Research on the Chemical Structures of Natural Perfume and Their Bioactivities%天然香料的化学结构和功能研究进展

    Institute of Scientific and Technical Information of China (English)

    邱明华

    2013-01-01

    This paper gives a brief review of the progress of research on the chemical structures of natural perfume and its bioactivity.%该文对近年一些天然香料化学成分的结构、生物活性、提取方法等研究结果进行了简要评论.

  14. Study on the Combination of OdorTheory about Material Basis of Chemical Medicine and Natural Medicine%从检测中西药气味物质基础探中西药理论会通

    Institute of Scientific and Technical Information of China (English)

    王光耀; 盛良; 王兴华; 汪宇; TeKian Keong; TheSiew Hoon; OoiCiat Hui

    2015-01-01

    Chemicals are chemical, and the natural medicine is also a chemical. Odor is produced by the chemical constituents of the medicine, so the testing "smell" is one of the basic methods to detect the chemical composition of drugs. It should pay attention to the relationship between the composition, smell, character and effect of both chemical medicine and natural medicine. The technology of electronic nose and electronic tongue can detect the smell of chemical medicine and natural medicine. Simple and fast asit is, thistechnologycan be used for the comparison and identification ofthe smell of medicine via studying the graphics that reflectchemical basis. The Pkavalue of chemicals can also be used to quantify the smell of natural medicine. By detecting the odor of chemical agents and nature medicines, the common material basis can be studied for the innovation and fusion of modern medicine and traditional Chinese medicine theory.%西药和中药都有化学成分,气味是由药品的化学成分产生的,气味检测是研究药品物质成分的基本方法之一.中西药研究都应该重视药品成分、气味、性质与疗效之间的关系,寻找两者物质基础与化学成分的共同规律.应用电子鼻与电子舌技术,能够检测中西药的气味,该技术检测所得到的图形,可视可辨,能够用于二者之间的比较与鉴别,方法简单快速.量化西药的Pka值,也可以用于量化中药气味.通过检测中西药气味,研究二者之间物质基础的共同点,实现中西药理论会通,以促进中西药理论的结合与创新.

  15. Chemical nature of soil humified fractions and their bioactivity Natureza química do húmus do solo e sua bioatividade

    Directory of Open Access Journals (Sweden)

    Luciano Pasqualoto Canellas

    2004-03-01

    Full Text Available The aim of this work was to evaluate the humus composition from an Ultisol from Campos dos Goytacazes, RJ, Brazil. Soil samples of four depths (0-0.05, 0.05-0.10, 0.10-0.20 and 0.20-0.40 m and its chemical nature were analysed by elemental composition, E4/E6 ratios and Fourier transformed infrared spectroscopy. The bioactivity of these humified substances was evaluated through their action on maize root growth and H+-ATPase activity of roots microsomes. In topsoil, the content of high condensed alkaline soluble humic substances is greater than that found in the subsuperficial layers. The chemical nature of humic and fulvic acids also varied with the soil depth. The humic acids isolated from the soil samples exhibited higher bioactivity compared with the fulvic acids. Moreover, the results suggest that more condensed humic substances can promote highest stimulation of the microsomal H+-ATPases from maize roots. These data reinforce the concept that the activity of the H+ pumps can be used as a biochemical marker for evaluation of humic substances bioactivity.O objetivo deste trabalho foi avaliar a composição do húmus de um Argissolo Amarelo de Campos dos Goytacazes, RJ, Brasil. Amostras de solo de quatro profundidades (0-0,05, 0,05-0,10, 0,10-0,20 e 0,20-0,40 m foram analisados mediante o fracionamento químico da matéria orgânica. As frações ácidos húmicos e fúlvicos foram extraídas e sua natureza química avaliada por meio da composição elementar, relação E4/E6 e espectroscopia de infravermelho transformada de Fourier. A bioatividade das substâncias húmicas foi avaliada mediante sua ação sobre o crescimento radicular de plântulas de milho e atividade da H+-ATPase da fração microssomal das raízes. Os resultados mostraram que é maior o conteúdo de substâncias húmicas alcalino solúveis mais condensadas na camada superficial do solo. A natureza química dos ácidos húmicos e fúlvicos também variou com a profundidade

  16. The chemical life(1).

    Science.gov (United States)

    Hodges, Nathan

    2015-01-01

    You write this narrative autoethnography to open up a conversation about our chemical lives. You go through your day with chemical mindfulness, questioning taken-for-granted ideas about natural and artificial, healthy and unhealthy, dependency and addiction, trying to understand the chemical messages we consume through the experiences of everyday life. You reflect on how messages about chemicals influence and structure our lives and why some chemicals are celebrated and some are condemned. Using a second-person narrative voice, you show how the personal is relational and the chemical is cultural. You write because you seek a connection, a chemical bond. PMID:24905820

  17. The chemical life(1).

    Science.gov (United States)

    Hodges, Nathan

    2015-01-01

    You write this narrative autoethnography to open up a conversation about our chemical lives. You go through your day with chemical mindfulness, questioning taken-for-granted ideas about natural and artificial, healthy and unhealthy, dependency and addiction, trying to understand the chemical messages we consume through the experiences of everyday life. You reflect on how messages about chemicals influence and structure our lives and why some chemicals are celebrated and some are condemned. Using a second-person narrative voice, you show how the personal is relational and the chemical is cultural. You write because you seek a connection, a chemical bond.

  18. 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. PMID:25475307

  19. Coupling chemical oxidation and biostimulation: Effects on the natural attenuation capacity and resilience of the native microbial community in alkylbenzene-polluted soil

    NARCIS (Netherlands)

    Martínez-Pascual, E.; Grotenhuis, J.T.C.; Solanas, A.M.; Viñas, M.

    2015-01-01

    Coupling chemical oxidation with bioremediation could be a cost-effective system to cope with soil and groundwater pollution. However, the effects of chemical oxidation on autochthonous microbial communities are scarcely known. A detailed analysis that considers both the efficiency of the two techno

  20. RT-qPCR analysis of putative beer-spoilage gene expression during growth of Lactobacillus brevis BSO 464 and Pediococcus claussenii ATCC BAA-344(T) in beer.

    Science.gov (United States)

    Bergsveinson, Jordyn; Pittet, Vanessa; Ziola, Barry

    2012-10-01

    Lactic acid bacteria (LAB) contamination of beer presents a continual economic threat to brewers. Interestingly, only certain isolates of LAB can grow in the hostile beer environment (e.g., as studied here, Lactobacillus brevis BSO 464 (Lb464) and a non-ropy isolate of Pediococcus claussenii ATCC BAA-344(T) (Pc344NR)), indicating that significant genetic specialization is required. The genes hitA, horA, horB, horC, and bsrA, which have been proposed to confer beer-spoiling ability to an organism, are suspected of counteracting the antimicrobial effects of hops. However, these genes are not present in the same combination (if at all) across beer-spoiling organisms. As such, we sought to investigate the extent to which these genes participate during Lb464 and Pc344NR mid-logarithmic growth in beer through reverse transcription quantitative PCR analysis. We first determined the optimal reference gene set needed for data normalization and, for each bacterium, established that two genes were needed for accurate assessment of gene expression. Following this, we found that horA expression was induced for Pc344NR, but not for Lb464, during growth in beer. Instead, horC expression was dramatically increased in Lb464 when growing in beer, whereas no change was detected for the other putative beer-spoilage-related genes. This indicates that HorC may be one of the principle mediators enabling growth of Lb464 in beer, whereas in Pc344NR, this may be attributable to HorA. These findings not only reveal that Lb464 and Pc344NR are unique in their beer-specific genetic expression profile but also indicate that a range of genetic specialization exists among beer-spoilage bacteria.

  1. 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.

  2. Satellite Retrievals of Karenia brevis Harmful Algal Blooms in the West Florida Shelf Using Neural Networks and Comparisons with Other Techniques

    Directory of Open Access Journals (Sweden)

    Ahmed El-habashi

    2016-05-01

    Full Text Available We describe the application of a Neural Network (NN previously developed by us, to the detection and tracking, of Karenia brevis Harmful Algal Blooms (KB HABs that plague the coasts of the West Florida Shelf (WFS using Visible Infrared Imaging Radiometer Suite (VIIRS satellite observations. Previous approaches for the detection of KB HABs in the WFS primarily used observations from the Moderate Resolution Imaging Spectroradiometer Aqua (MODIS-A satellite. They depended on the remote sensing reflectance signal at the 678 nm chlorophyll fluorescence band (Rrs678 needed for both the normalized fluorescence height (nFLH and Red Band Difference algorithms (RBD currently used. VIIRS which has replaced MODIS-A, unfortunately does not have a 678 nm fluorescence channel so we customized the NN approach to retrieve phytoplankton absorption at 443 nm (aph443 using only Rrs measurements from existing VIIRS channels at 486, 551 and 671 nm. The aph443 values in these retrieved VIIRS images, can in turn be correlated to chlorophyll-a concentrations [Chla] and KB cell counts. To retrieve KB values, the VIIRS NN retrieved aph443 images are filtered by applying limiting constraints, defined by (i low backscatter at Rrs 551 nm and (ii a minimum aph443 value known to be associated with KB HABs in the WFS. The resulting filtered residual images, are then used to delineate and quantify the existing KB HABs. Comparisons with KB HABs satellite retrievals obtained using other techniques, including nFLH, as well as with in situ measurements reported over a four year period, confirm the viability of the NN technique, when combined with the filtering constraints devised, for effective detection of KB HABs.

  3. Chemical, mineralogical and molecular biological characterization of the rocks and fluids from a natural gas storage deep reservoir as a baseline for the effects of geological hydrogen storage

    Science.gov (United States)

    Morozova, Daria; Kasina, Monika; Weigt, Jennifer; Merten, Dirk; Pudlo, Dieter; Würdemann, Hilke

    2014-05-01

    Planned transition to renewable energy production from nuclear and CO2-emitting power generation brings the necessity for large scale energy storage capacities. One possibility to store excessive energy produced is to transfer it to chemical forms like hydrogen which can be subsequently injected and stored in subsurface porous rock formations like depleted gas reservoirs and presently used gas storage sites. In order to investigate the feasibility of the hydrogen storage in the subsurface, the collaborative project H2STORE ("hydrogen to store") was initiated. In the scope of this project, potential reactions between microorganism, fluids and rocks induced by hydrogen injection are studied. For the long-term experiments, fluids of natural gas storage are incubated together with rock cores in the high pressure vessels under 40 bar pressure and 40° C temperature with an atmosphere containing 5.8% He as a tracer gas, 3.9% H2 and 90.3% N2. The reservoir is located at a depth of about 2 000 m, and is characterized by a salinity of 88.9 g l-1 NaCl and a temperature of 80° C and therefore represents an extreme environment for microbial life. First geochemical analyses showed a relatively high TOC content of the fluids (about 120 mg l-1) that were also rich in sodium, potassium, calcium, magnesium and iron. Remarkable amounts of heavy metals like zinc and strontium were also detected. XRD analyses of the reservoir sandstones revealed the major components: quartz, plagioclase, K-feldspar, anhydrite and analcime. The sandstones were intercalated by mudstones, consisting of quartz, plagioclase, K-feldspar, analcime, chlorite, mica and carbonates. Genetic profiling of amplified 16S rRNA genes was applied to characterize the microbial community composition by PCR-SSCP (PCR-Single-Strand-Conformation Polymorphism) and DGGE (Denaturing Gradient Gel Electrophoresis). First results indicate the presence of microorganisms belonging to the phylotypes alfa-, beta- and gamma

  4. Chemical composition of inks of diverse marine molluscs suggests convergent chemical defenses.

    Science.gov (United States)

    Derby, Charles D; Kicklighter, Cynthia E; Johnson, P M; Zhang, Xu

    2007-05-01

    Some marine molluscs, notably sea hares, cuttlefish, squid, and octopus, release ink when attacked by predators. The sea hare Aplysia californica releases secretions from the ink gland and opaline gland that protect individuals from injury or death from predatory spiny lobsters through a combination of mechanisms that include chemical deterrence, sensory disruption, and phagomimicry. The latter two mechanisms are facilitated by millimolar concentrations of free amino acids (FAA) in sea hare ink and opaline, which stimulate the chemosensory systems of predators, ultimately leading to escape by sea hares. We hypothesize that other inking molluscs use sensory disruption and/or phagomimicry as a chemical defense. To investigate this, we examined concentrations of 21 FAA and ammonium in the defensive secretions of nine species of inking molluscs: three sea hares (Aplysia californica, Aplysia dactylomela, Aplysia juliana) and six cephalopods (cuttlefish: Sepia officinalis; squid: Loligo pealei, Lolliguncula brevis, Dosidicus gigas; octopus: Octopus vulgaris, Octopus bimaculoides). We found millimolar levels of total FAA and ammonium in these secretions, and the FAA in highest concentration were taurine, aspartic acid, glutamic acid, alanine, and lysine. Crustaceans and fish, which are major predators of these molluscs, have specific receptor systems for these FAA. Our chemical analysis supports the hypothesis that inking molluscs have the potential to use sensory disruption and/or phagomimicry as a chemical defense. PMID:17393278

  5. 环介导恒温扩增技术快速检测短凯伦藻%Rapid Detection of Karenia brevis (Dinophyceae) by Loop-mediated Isothermal Amplification (LAMP)

    Institute of Scientific and Technical Information of China (English)

    张凤英; 石彦红; 马凌波; 徐兆礼

    2012-01-01

    短凯伦藻(Karenia brevis)是一种有毒赤潮微藻,所产生的短藻毒素对海洋生物乃至人类都有毒害作用,为加强对短凯伦藻赤潮的监控,建立了稳定的短凯伦藻环介导恒温扩增(LAMP)鉴定体系,在此基础上进行了特异性和灵敏性验证.特异性实验结果显示只有短凯伦藻或者含短凯伦藻的模板呈现阳性反应,其他微藻为阴性反应,从而验证了该LAMP方法的特异性;同时,对短凯伦藻的基因组DNA进行一系列10倍稀释作为敏感度实验的模板,并与常规PCR做了对比,结果表明:短凯伦藻的LAMP方法最低检测限度为50 pg,敏感度比常规PCR高10倍.LAMP产物鉴定不需要常规的胶电泳过程,直接采用肉眼观察的方法,在含有短凯伦藻的阳性反应管中会出现白色混浊,加入syBRò Green I染料呈现绿色,而未含有短凯伦藻的阴性管为澄清,染色后仍为原来的橙色.因此,该方法操作简便、特异性强、灵敏度高而成本低,在赤潮原因种检测监控方面具有良好的应用前景.%Karenia brevis (Gymnodinium breve) is an unarmored, non-peridinin-containing dinoflagellate. It produces lipophilic brevetoxin that can harm many marine animals, eg. fish, birds and shellfish. As for human, brevetoxin can cause respiratory distress by inhalation and food poisoning by consumption of contaminated shellfish. Previous methods for the detection of A', brevis depend on microscopy analysis, which is time-consuming and requires a considerable amount of expertise and skill. Molecular methods have also been applied to detect K. brevis, e.g. real-time PCR and DNA hybridization assay. However, there are some inevitable disadvantages for the two methods, such as expensive reagents and equipment, or fussy approaches. Loop-mediated isothermal amplification (LAMP) is a specific nucleic acid amplification method that is easy to perform. The LAMP method can amplify nucleic acids under isothermal conditions at

  6. Direct High-Precision Measurements of the (87)Sr/(86)Sr Isotope Ratio in Natural Water without Chemical Separation Using Thermal Ionization Mass Spectrometry Equipped with 10(12) Ω Resistors.

    Science.gov (United States)

    Li, Chao-Feng; Guo, Jing-Hui; Chu, Zhu-Yin; Feng, Lian-Jun; Wang, Xuan-Ce

    2015-07-21

    Thermal ionization mass spectrometry (TIMS) allows excellent precision for determining Sr isotope ratios in natural water samples. Traditionally, a chemical separation procedure using cation exchange resin has been employed to obtain a high purity Sr fraction from natural water, which makes sample preparation time-consuming. In this study, we present a rapid and precise method for the direct determination of the Sr isotope ratio of natural water using TIMS equipped with amplifiers with two 10(12) Ω resistors. To eliminate the (87)Rb isobaric interference, Re ribbons are used as filaments, providing a significant advantage over W ribbons in the inhibition of Rb(+) emission, based on systematically examining a series of NIST SRM987 standard doping with various amounts of Rb using Re and W ribbons. To validate the applicability of our method, twenty-two natural water samples, including different water types (rain, snow, river, lake and drinking water), that show a large range in Sr content variations (2.54-922.8 ppb), were collected and analyzed from North and South China. Analytical results show good precision (0.003-0.005%, 2 RSE) and the method was further validated by comparative analysis of the same water with and without chemical separation. The method is simple and rapid, eliminates sample preparation time, and prevents potential contamination during complicated sample-preparation procedures. Therefore, a high sample throughput inherent to the TIMS can be fully utilized.

  7. Coexpression of Lactobacillus brevis ADH with GDH or G6PDH in Arxula adeninivorans for the synthesis of 1-(R)-phenylethanol.

    Science.gov (United States)

    Rauter, Marion; Prokoph, Alexandra; Kasprzak, Jakub; Becker, Karin; Baronian, Keith; Bode, Rüdiger; Kunze, Gotthard; Vorbrodt, H- Matthias

    2015-06-01

    The yeast Arxula adeninivorans was used for the overexpression of an ADH gene of Lactobacillus brevis coding for (R)-specific alcohol dehydrogenase (LbADH) to synthesise enantiomerically pure 1-(R)-phenylethanol. Glucose dehydrogenase gene from Bacillus megaterium (BmGDH) or glucose 6-phosphate dehydrogenase of Bacillus pumilus (BpG6PDH) were coexpressed in Arxula to regenerate the cofactor NADPH by oxidising glucose or glucose 6-phosphate. The yeast strain expressing LbADH and BpG6PDH produced 5200 U l(-1) ADH and 370 U l(-1) G6PDH activity, whereas the strain expressing LbADH and BmGDH produced 2700 U l(-1) ADH and 170 U l(-1) GDH activity. However, the crude extract of both strains reduced 40 mM acetophenone to pure 1-(R)-phenylethanol with an enantiomeric excess (ee) of >99 % in 60 min without detectable by-products. An increase in yield was achieved using immobilised crude extracts (IEs), Triton X-100 permeabilised cells (PCs) and permeabilised immobilised cells (PICs) with PICs being most stable with GDH regeneration over 52 cycles. Even though the activity and synthesis rate of 1-(R)-phenylethanol with the BpG6PDH and LbADH coexpressing strain was higher, the BmGDH-LbADH strain was more stable over successive reaction cycles. This, combined with its higher total turnover number (TTN) of 391 mol product per mole NADP(+), makes it the preferred strain for continuous reaction systems. The initial non-optimised semi-continuous reaction produced 9.74 g l(-1) day(-1) or 406 g kg(-1) dry cell weight (dcw) day(-1) isolated 1-(R)-phenylethanol with an ee of 100 % and a TTN of 206 mol product per mole NADP(+). In conclusion, A. adeninivorans is a promising host for LbADH and BpG6PDH or BmGDH production and offers a simple method for the production of enantiomerically pure alcohols.

  8. Pharmaceuticals may disrupt natural chemical information flows and species interactions in aquatic systems: ideas and perspectives on a hidden global change

    NARCIS (Netherlands)

    Donk, van E.; Peacor, S.; Grosser, K.; Senerpont Domis, de L.N.; Lürling, M.F.L.L.W.

    2015-01-01

    Over the last decades, anthropogenic activities have discharged into the environment many manmade chemicals. There is a rising concern regarding pharmaceutical products and their spread into the environment (e.g. Kümmerer 2008). Due to the enormous quantities consumed, anti-inflammatories, antibioti

  9. Pharmaceuticals may disrupt natural chemical information flows and species interactions in aquatic systems: ideas and perspectives on a hidden global change

    NARCIS (Netherlands)

    Donk, van E.; Peacor, S.; Grosser, K.; Senerpont Domis, de L.N.; Lürling, M.F.L.L.W.

    2016-01-01

    Over the last decades, anthropogenic activities have discharged into the environment many manmade chemicals. There is a rising concern regarding pharmaceutical products and their spread into the environment (e.g. Kümmerer 2008). Due to the enormous quantities consumed, anti-inflammatories, antibioti

  10. Pharmaceuticals may disrupt the natural chemical information flows and species interactions in aquatic systems: ideas and perspectives on a hidden global change

    NARCIS (Netherlands)

    van Donk, E.; Peacor, S.; Grosser, K.; De Senerpont Domis, Lisette; Lurling, M.; de Voogt, Pim

    2016-01-01

    Over the last decades, anthropogenic activities have discharged into the environment many manmade chemicals. There is a rising concern regarding pharmaceutical products and their spread into the environment (e.g. Kümmerer 2008). Due to the enormous quantities consumed, anti-inflammatories, antibioti

  11. 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.

  12. Chemicals from coal

    Energy Technology Data Exchange (ETDEWEB)

    Harold A. Wittcoff; Bryan G. Reuben; Jeffrey S. Plotkin

    2004-12-01

    This chapter contains sections titled: Chemicals from Coke Oven Distillate; The Fischer-Tropsch Reaction; Coal Hydrogenation; Substitute Natural Gas (SNG); Synthesis Gas Technology; Calcium Carbide; Coal and the Environment; and Notes and References

  13. Pharmaceuticals may disrupt the natural chemical information flows and species interactions in aquatic systems: ideas and perspectives on a hidden global change

    OpenAIRE

    Van Donk, E.; Peacor, S.; Grosser, K; de Senerpont Domis, Lisette; Lurling, M.; De Voogt, Pim

    2016-01-01

    Over the last decades, anthropogenic activities have discharged into the environment many manmade chemicals. There is a rising concern regarding pharmaceutical products and their spread into the environment (e.g. Kümmerer 2008). Due to the enormous quantities consumed, anti-inflammatories, antibiotics, anti-depressives, hormones and blood lipid regulators are found in almost all aquatic environments (Kolpin et al. 2002; Loos et al. 2009). Most pharmaceuticals tend to enter the aquatic environ...

  14. 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.; Isabel C. F. R. Ferreira; 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...

  15. 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 ...

  16. 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.

  17. Improved method for the determination of nonpurgeable suspended organic carbon in natural water by silver filter filtration, wet chemical oxidation, and infrared spectrometry

    Science.gov (United States)

    Burkhardt, M.R.; Brenton, R.W.; Kammer, J.A.; Jha, V.K.; O'Mara-Lopez, P. G.; Woodworth, M.T.

    1999-01-01

    Precision and accuracy are reported for the first time for the analysis of nonpurgeable suspended organic carbon by silver membrane filtration followed by wet chemical oxidation. A water sample is pressure filtered through a 0.45-??m-pore-size, 47-mm-diameter silver membrane filter. The silver membrane filter then is cut into ribbons and placed in a flame-sealable glass ampule. The organic material trapped on the membrane filter strips is acidified, purged with oxygen to remove inorganic carbonates and volatile organic compounds, and oxidized to carbon dioxide (CO2) using phosphoric acid and potassium persulfate in the sealed glass ampule. The resulting CO2 is measured by a nondispersive infrared CO2 detector. The amount of CO2 is proportional to the concentration of chemically oxidizable nonpurgeable organic carbon in the environmental water sample. The quantitation and method detection limit for routine analysis is 0.2 mg/L. The average percent recovery in five representative matrices was 97 ?? 11%. The errors associated with sampling and sample preparation of nonpurgeable suspended organic carbon are also described.Precision and accuracy are reported for the first time for the analysis of nonpurgeable suspended organic carbon by silver membrane filtration followed by wet chemical oxidation. A water sample is pressure filtered through a 0.45-??m-pore-size, 47-mm-diameter silver membrane filter. The silver membrane filter then is cut into ribbons and placed in a flame-sealable glass ampule. The organic material trapped on the membrane filter strips is acidified, purged with oxygen to remove inorganic carbonates and volatile organic compounds, and oxidized to carbon dioxide (CO2) using phosphoric acid and potassium persulfate in the sealed glass ampule. The resulting CO2 is measured by a nondispersive infrared CO2 detector. The amount of CO2 is proportional to the concentration of chemically oxidizable nonpurgeable organic carbon in the environmental water sample

  18. Comparison between physico-chemical properties of the technical Cashew Nut Shell Liquid (CNSL and those natural extracted from solvent and pressing

    Directory of Open Access Journals (Sweden)

    Francisco H. A Rodrigues

    2011-01-01

    Full Text Available Cashew nut shell liquid (CNSL is a by-product of the cashew kernel industry, applied mainly to produce polymeric derivatives. The technical CNSL (CNSLT was obtained industrially, extracted by roasting the cashew nut shells at temperatures between 180 and 200 ºC. Two methods were used to produce natural CNSL. For the extraction of CNSLNP, the cashew nut shells were pressed at room temperature. CNSLNS was extracted in hexane at room temperature and recovered at 50 ºC. A comparison was made of the composition determined by HPLC and properties generated by viscosity measurements and also by TG, DSC and IPDT (integral procedural decomposition temperature. Natural CNSLs displayed higher content of cardol and anacardic acid and lower percentage of cardanol than CNSLT. The higher content of cardanol in CNSLNS was the major difference between natural CNSLs. CNSLNP had higher levels of impurity, higher viscosity, lower thermoxidative stabilities and lower ebullition temperature. The CNSL obtained by cold solvent extraction and recovery at 50 ºC better preserves the original properties of the liquid.

  19. Fluid dynamics, particulate segregation, chemical processes, and natural ore analog discussions that relate to the potential for criticality in Hanford tanks

    Energy Technology Data Exchange (ETDEWEB)

    Barney, G.S.

    1996-09-27

    This report presents an in-depth review of the potential for nuclear criticality to occur in Hanford defense waste tanks during past, current and future safe storage and maintenance operations. The report also briefly discusses the potential impacts of proposed retrieval activities, although retrieval was not a main focus of scope. After thorough review of fluid dynamic aspects that focus on particle segregation, chemical aspects that focus on solubility and adsorption processes that might concentrate plutonium and/or separate plutonium from the neutron absorbers in the tank waste, and ore-body formation and mining operations, the interdisciplinary team has come to the conclusion that there is negligible risk of nuclear critically under existing storage conditions in Hanford site underground waste storage tanks. Further, for the accident scenarios considered an accidental criticality is incredible.

  20. Chemically optimized antimyosin Fab conjugates with chelating polymers: importance of the nature of the protein-polymer single site covalent bond for biodistribution and infarction localization.

    Science.gov (United States)

    Trubetskoy, V S; Narula, J; Khaw, B A; Torchilin, V P

    1993-01-01

    Murine antimyosin Fab fragment was conjugated with 111In-labeled N-terminal-modified DTPA-polylysine using three bifunctional reagents: N-hydroxysuccinimide esters of 3-(2-pyridyldithio)propionic acid (SPDP conjugate), 4-(maleimidomethyl)cyclohexanecarboxylic acid (SMCC conjugate) and bromoacetic acid (BrAc conjugate) for potential localization of experimental myocardial infarction. Using various antibody preparations and a rabbit acute myocardial infarction model the following parameters were observed: (1) an in vitro antigen binding activity of SPDP conjugate = SMCC conjugate > BrAc conjugate, (2) a blood clearance rate of SPDP conjugate > BrAc conjugate > SMCC conjugate, (3) a liver and splenic accumulation of SPDP conjugate > BrAc conjugate > SMCC conjugate, and (4) the infarcted tissue activity showed an accumulation of SMCC conjugate > SPDP conjugate > BrAc conjugate. This study exemplifies the importance of rational chemical design of antimyosin Fab-chelating polymer conjugate for improved target tissue localization in vivo.

  1. The Nature of the Chemical Bond in Linear Three-Body Systems: From I3– to Mixed Chalcogen/Halogen and Trichalcogen Moieties

    Directory of Open Access Journals (Sweden)

    M. Carla Aragoni

    2007-01-01

    Full Text Available The 3 centre-4 electrons (3c-4e and the donor/acceptor or charge-transfer models for the description of the chemical bond in linear three-body systems, such as I3– and related electron-rich (22 shell electrons systems, are comparatively discussed on the grounds of structural data from a search of the Cambridge Structural Database (CSD. Both models account for a total bond order of 1 in these systems, and while the former fits better symmetric systems, the latter describes better strongly asymmetric situations. The 3c-4e MO scheme shows that any linear system formed by three aligned closed-shell species (24 shell electrons overall has reason to exist provided that two electrons are removed from it to afford a 22 shell electrons three-body system: all combinations of three closed-shell halides and/or chalcogenides are considered here. A survey of the literature shows that most of these three-body systems exist. With some exceptions, their structural features vary continuously from the symmetric situation showing two equal bonds to very asymmetric situations in which one bond approaches to the value corresponding to a single bond and the second one to the sum of the van der Waals radii of the involved atoms. This indicates that the potential energy surface of these three-body systems is fairly flat, and that the chemical surrounding of the chalcogen/halogen atoms can play an important role in freezing different structural situations; this is well documented for the I3– anion. The existence of correlations between the two bond distances and more importantly the linearity observed for all these systems, independently on the degree of their asymmetry, support the state of hypervalency of the central atom.

  2. Biocide tolerance, phenotypic and molecular response of lactic acid bacteria isolated from naturally-fermented Aloreña table to different physico-chemical stresses.

    Science.gov (United States)

    Casado Muñoz, María Del Carmen; Benomar, Nabil; Lavilla Lerma, Leyre; Knapp, Charles W; Gálvez, Antonio; Abriouel, Hikmate

    2016-12-01

    Lactic acid bacteria (LAB) isolated throughout the fermentation process of Aloreña table olives were found to be resistant at least to three antibiotics (Casado Muñoz et al., 2014); however, most were sensitive to the biocides tested in this study (with minimum inhibitory concentrations [MIC] below the epidemiological cut-off values). 2-15% of the isolates were found to be biocide resistant: Leuconostoc Pseudomesenteroides, which were resistant to hexachlorophene, and Lactobacillus pentosus to cetrimide and hexadecylpiridinium. We analyzed the effect of different physico-chemical stresses, including antimicrobials, on the phenotypic and genotypic responses of LAB, providing new insights on how they become resistant in a changing environment. Results indicated that similar phenotypic responses were obtained under three stress conditions: antimicrobials, chemicals and UV light. Susceptibility patterns to antibiotics changed: increasing MICs for ampicillin, chloramphenicol, ciprofloxacin, teicoplanin and tetracycline, and decreasing the MICs for clindamycin, erythromycin, streptomycin and trimethoprim in most strains. Statistically, cross resistance between different antibiotics was detected in all stress conditions. However, expression profiles of selected genes involved in stress/resistance response (rpsL, recA, uvrB and srtA) differed depending on the stress parameter, LAB species and strain, and the target gene. We conclude that, despite the uniform phenotypic response to stresses, the repertoire of induced and repressed genes differs. So, a search for a target to improve stress tolerance of LAB, especially those of importance as starter/protective cultures or probiotics, may depend on the individual screening of each strain, even though we could predict the antibiotic phenotypic response to all stresses. PMID:27554140

  3. Comparison between physico-chemical properties of the technical Cashew Nut Shell Liquid (CNSL) and those natural extracted from solvent and pressing

    OpenAIRE

    Francisco H. A Rodrigues; Francisco C. F França; de Souza, José R. R.; Nágila M. P. S. Ricardo; Judith P. de A. Feitosa

    2011-01-01

    Cashew nut shell liquid (CNSL) is a by-product of the cashew kernel industry, applied mainly to produce polymeric derivatives. The technical CNSL (CNSLT) was obtained industrially, extracted by roasting the cashew nut shells at temperatures between 180 and 200 ºC. Two methods were used to produce natural CNSL. For the extraction of CNSLNP, the cashew nut shells were pressed at room temperature. CNSLNS was extracted in hexane at room temperature and recovered at 50 ºC. A comparison was made of...

  4. 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.

  5. Accumulation of Dechlorane Plus flame retardant in terrestrial passerines from a nature reserve in South China: the influences of biological and chemical variables.

    Science.gov (United States)

    Peng, Ying; Wu, Jiang-Ping; Tao, Lin; Mo, Ling; Zheng, Xiao-Bo; Tang, Bin; Luo, Xiao-Jun; Mai, Bi-Xian

    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 fanti values (the isomer fractions of anti-DP) in the red-whiskered bulbul and the oriental magpie-robin. Additionally, the fanti values were significantly negatively correlated to ∑DP concentrations for the individual bird samples, suggesting the influence of DP concentrations on the isomeric profiles. PMID:25666277

  6. Chemical modifications of a natural xanthone and antimicrobial activity against multidrug resistant Staphylococcus aureus and cytotoxicity against human tumor cell lines

    Directory of Open Access Journals (Sweden)

    Ana Camila Micheletti

    2011-01-01

    Full Text Available A series of 15 ω-aminoalkoxylxanthones containing methyl, ethyl, propyl, tert-butylamino and piperidinyl moieties were synthesized from a natural xanthone isolated from a lichen species. These compounds were tested for their in vitro antibacterial properties against Gram-positive and Gram-negative bacteria and cytotoxicity against a number of human tumor cell lines was too evaluated. The newly synthesized derivatives revealed selective activity against Staphylococcus aureus (Gram-positive, and the most promising results are for a multidrug resistant strain, for which six of these compounds showed good activity (MICs 4 µg/mL. Many derivatives inhibited tumor cells growth and most compounds were active on multiple lines.

  7. Chemical modifications of a natural xanthone and antimicrobial activity against multidrug resistant Staphylococcus aureus and cytotoxicity against human tumor cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Micheletti, Ana Camila; Honda, Neli Kika; Lima, Denis Pires de; Beatriz, Adilson [Universidade Federal de Mato Grosso do Sul (DQ/UFMS), Campo Grande, MS (Brazil). Dept. de Quimica; Sant' ana, Maria Rita; Carvalho, Nadia Cristina Pereira [Universidade Federal de Mato Grosso do Sul (SAC/UFMS), Campo Grande, MS (Brazil). Secao de Analises Clinicas; Matos, Maria de Fatima Cepa; Queiroz, Lyara Meira Marinho; Bogo, Danielle [Universidade Federal de Mato Grosso do Sul (DFB/UFMS), Campo Grande, MS (Brazil). Dept. de Farmacia-Bioquimica; Zorzatto, Jose Roberto [Universidade Federal de Mato Grosso do Sul (DQ/UFMS), Campo Grande, MS (Brazil). Faculdade de Computacao

    2011-07-01

    A series of 15 {omega}-aminoalkoxylxanthones containing methyl, ethyl, propyl, tert-butylamino and piperidinyl moieties were synthesized from a natural xanthone isolated from a lichen species. These compounds were tested for their in vitro antibacterial properties against Gram-positive and Gram-negative bacteria and cytotoxicity against a number of human tumor cell lines was too evaluated. The newly synthesized derivatives revealed selective activity against Staphylococcus aureus (Gram-positive), and the most promising results are for a multidrug resistant strain, for which six of these compounds showed good activity (MICs 4 {mu}g/mL). Many derivatives inhibited tumor cells growth and most compounds were active on multiple lines. (author)

  8. 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.

  9. 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.

  10. Can Small Chemical Modifications of Natural Pan-inhibitors Modulate the Biological Selectivity? The Case of Curcumin Prenylated Derivatives Acting as HDAC or mPGES-1 Inhibitors.

    Science.gov (United States)

    Iranshahi, Mehrdad; Chini, Maria Giovanna; Masullo, Milena; Sahebkar, Amirhossein; Javidnia, Azita; Chitsazian Yazdi, Mahsa; Pergola, Carlo; Koeberle, Andreas; Werz, Oliver; Pizza, Cosimo; Terracciano, Stefania; Piacente, Sonia; Bifulco, Giuseppe

    2015-12-24

    Curcumin, or diferuloylmethane, a polyphenolic molecule isolated from the rhizome of Curcuma longa, is reported to modulate multiple molecular targets involved in cancer and inflammatory processes. On the basis of its pan-inhibitory characteristics, here we show that simple chemical modifications of the curcumin scaffold can regulate its biological selectivity. In particular, the curcumin scaffold was modified with three types of substituents at positions C-1, C-8, and/or C-8' [C5 (isopentenyl, 5-8), C10 (geranyl, 9-12), and C15 (farnesyl, 13, 14)] in order to make these molecules more selective than the parent compound toward two specific targets: histone deacetylase (HDAC) and microsomal prostaglandin E2 synthase-1 (mPGES-1). From combined in silico and in vitro analyses, three selective inhibitors by proper substitution at position 8 were revealed. Compound 13 has improved HDAC inhibitory activity and selectivity with respect to the parent compound, while 5 and 9 block the mPGES-1 enzyme. We hypothesize about the covalent interaction of curcumin, 5, and 9 with the mPGES-1 binding site.

  11. Can Small Chemical Modifications of Natural Pan-inhibitors Modulate the Biological Selectivity? The Case of Curcumin Prenylated Derivatives Acting as HDAC or mPGES-1 Inhibitors.

    Science.gov (United States)

    Iranshahi, Mehrdad; Chini, Maria Giovanna; Masullo, Milena; Sahebkar, Amirhossein; Javidnia, Azita; Chitsazian Yazdi, Mahsa; Pergola, Carlo; Koeberle, Andreas; Werz, Oliver; Pizza, Cosimo; Terracciano, Stefania; Piacente, Sonia; Bifulco, Giuseppe

    2015-12-24

    Curcumin, or diferuloylmethane, a polyphenolic molecule isolated from the rhizome of Curcuma longa, is reported to modulate multiple molecular targets involved in cancer and inflammatory processes. On the basis of its pan-inhibitory characteristics, here we show that simple chemical modifications of the curcumin scaffold can regulate its biological selectivity. In particular, the curcumin scaffold was modified with three types of substituents at positions C-1, C-8, and/or C-8' [C5 (isopentenyl, 5-8), C10 (geranyl, 9-12), and C15 (farnesyl, 13, 14)] in order to make these molecules more selective than the parent compound toward two specific targets: histone deacetylase (HDAC) and microsomal prostaglandin E2 synthase-1 (mPGES-1). From combined in silico and in vitro analyses, three selective inhibitors by proper substitution at position 8 were revealed. Compound 13 has improved HDAC inhibitory activity and selectivity with respect to the parent compound, while 5 and 9 block the mPGES-1 enzyme. We hypothesize about the covalent interaction of curcumin, 5, and 9 with the mPGES-1 binding site. PMID:26588603

  12. Natural gas; Gas Natural

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Carlos A.; Moraes, Claudia C.D. [Eletricidade de Sao Paulo S.A. (ELETROPAULO), Sao Paulo, SP (Brazil); Fonseca, Carlos H.F. [Centrais Eletricas de Santa Catarina S.A., Florianopolis, SC (Brazil); Silva, Clecio Fabricio da; Alves, Ricardo P. [Companhia Paranaense de Energia (COPEL), Curitiba, PR (Brazil); Sposito, Edivaldo Soares; Hulle, Lutero [Espirito Santo Centrais Eletricas S.A. (ESCELSA), Vitoria, ES (Brazil); S. Martins, Icaro da [Centrais Eletricas do Norte do Brasil S.A. (ELETRONORTE), Belem, PA (Brazil); Vilhena, Joao Luiz S. de [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil); Fagundes, Zaluar Aquino [Companhia Estadual de Energia Eletrica do Estado do Rio Grande do Sul, Porto Alegre, RS (Brazil)

    1996-12-31

    An increase in the consumption of natural gas in Brazil is an expected fact in what concerns energetic planning. This work presents the existing situation in what concerns natural gas utilization in the main world economies, as well as an analysis of the participation of this fuel among the energy final consumption per sources. The Brazilian consumption of natural gas is also analysed as well as the international agreement between Brazil and Bolivia for natural gas commercialization. Some legal, institutional and political aspects related to natural gas commercialization are also discussed. Finally, several benefits to be brought by the utilization of natural gas are presented 10 refs., 3 tabs.

  13. Solution-phase parallel synthesis of a pharmacophore library of HUN-7293 analogues: a general chemical mutagenesis approach to defining structure-function properties of naturally occurring cyclic (depsi)peptides.

    Science.gov (United States)

    Chen, Yan; Bilban, Melitta; Foster, Carolyn A; Boger, Dale L

    2002-05-15

    HUN-7293 (1), a naturally occurring cyclic heptadepsipeptide, is a potent inhibitor of cell adhesion molecule expression (VCAM-1, ICAM-1, E-selectin), the overexpression of which is characteristic of chronic inflammatory diseases. Representative of a general approach to defining structure-function relationships of such cyclic (depsi)peptides, the parallel synthesis and evaluation of a complete library of key HUN-7293 analogues are detailed enlisting solution-phase techniques and simple acid-base liquid-liquid extractions for isolation and purification of intermediates and final products. Significant to the design of the studies and unique to solution-phase techniques, the library was assembled superimposing a divergent synthetic strategy onto a convergent total synthesis. An alanine scan and N-methyl deletion of each residue of the cyclic heptadepsipeptide identified key sites responsible for or contributing to the biological properties. The simultaneous preparation of a complete set of individual residue analogues further simplifying the structure allowed an assessment of each structural feature of 1, providing a detailed account of the structure-function relationships in a single study. Within this pharmacophore library prepared by systematic chemical mutagenesis of the natural product structure, simplified analogues possessing comparable potency and, in some instances, improved selectivity were identified. One potent member of this library proved to be an additional natural product in its own right, which we have come to refer to as HUN-7293B (8), being isolated from the microbial strain F/94-499709.

  14. Parallels with nature

    Science.gov (United States)

    2014-10-01

    Adam Nelson and Stuart Warriner, from the University of Leeds, talk with Nature Chemistry about their work to develop viable synthetic strategies for preparing new chemical structures in parallel with the identification of desirable biological activity.

  15. 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.

  16. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. 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)

  18. 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

  19. 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

  20. Chemical-mechanical coupling observed for depleted oil reservoirs subjected to long-term CO2-exposure - A case study of the Werkendam natural CO2 analogue field

    Science.gov (United States)

    Hangx, Suzanne; Bakker, Elisenda; Bertier, Pieter; Nover, Georg; Busch, Andreas

    2015-10-01

    Geological storage of CO2 is one of the most promising technologies to rapidly reduce anthropogenic emissions of carbon dioxide. In order to ensure storage integrity, it is important to understand the effect of long-term CO2/brine/rock interactions on the mechanical behaviour of a storage complex. As most of these reactions are too slow to reproduce on laboratory timescales, we studied a natural CO2 analogue reservoir (the Röt Fringe Sandstone, Werkendam field, the Netherlands; 125-135 Ma of CO2-exposure) and its unreacted counterpart. We focused on CO2-induced mineralogical and porosity-permeability changes, and their effect on mechanical behaviour of both intact rock and simulated fault gouge. Overall, CO2-exposure did not lead to drastic mineralogical changes. The CO2-exposed material shows a stronger dependence of permeability on porosity, which is attributed to differences in diagenesis (closed-system diagenesis and hydrocarbon emplacement) taking place before CO2 charging. The limited extent of reaction was in part the result of bitumen coatings protecting specific mineral phases from reaction. In local, mm-sized zones displaying significant anhydrite cement dissolution, enhanced porosity was observed. For most of the reservoir the long-term mechanical behaviour after CO2-exposure could be described by the behaviour of the unreacted sandstone, while these more 'porous' zones had a lower rock strength. In addition, CO2-exposure did not affect the fault friction behaviour, and slip is expected to result in stable sliding. Simple stress path calculations predict that reservoir failure due to depletion and injection is unlikely, even for the 'porous' zones, nor will fault reactivation occur for realistic injection scenarios.

  1. Chemical reactions of actinides with groundwater colloids. Studies of transferability of laboratory data to natural conditions. The aquiferous system in Gorleben. Interim report. Reported period: 1.2.1993-31.12.1993

    International Nuclear Information System (INIS)

    This study deals with the chemical interreaction between actinides and groundwater-colloids in selected aquiferes in the overburden of the planned final storage site for radioactive matter near Gorleben (Lower Saxony). As colloids have other transport properties than dissolved metal ions the interaction of actinides and groundwater-colloids has an important influence on their migration and is therefore essentially important for longterm-safety analyses. In order to study interaction of actinides with groundwater-colloids selected groundwaters were conditioned with trace concentrations of the actinides TH, Np, Pu, Am and Cm. For hexavalent actinides one used the analytical data of natural uranium in the groundwaters. In order to determine the humic-colloid-bound parts of the actinides the conditioned ground waters were filtered with a pore width of 1 nm and actinide concentration was determined with radiometry. (orig./EF)

  2. 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

  3. Hypothesis on Building of Chemical Constituent Element System of Cold-Heat Nature Based on Study of "Nature-Structure Relationship" of Traditional Chinese Medicine%从中药“性-构关系”探索构建寒热药性成分要素表征体系的研究构想

    Institute of Scientific and Technical Information of China (English)

    付先军; 王鹏; 王振国

    2011-01-01

    Nature theory of Chinese herbal medicine is a major constituent part of traditional Chinese medicine (TCM) theory. Modern study on nature theory of Chinese herbal medicine has been turned into a hotspot and leading edge in the research field of TCM. The hypothesis of "Nature-Structure Relationship" of TCM was proposed based on the hypothesis of "Nature-Effect-Material Trialism", so as to build the Chemical Constituent Element System (CCES) of cold-heat nature. Technical problems in the study of "Nature-Structure Relationship" were analyzed and the resolve methods were also discussed. A preliminary study implied that some Molecular Structural Characterization (MSC), such as Gibbs free energy, showed strong relationship with cold-heat nature of the herbals in the study. It proved that a functional relationship may exist between herbal medicine and MSC of its chemical constituent. It implied that CCES of cold-heat nature can be built based on the study of "Nature-Structure Relation ship". The study of "Nature-Structure Relationship" may explore a new research approach for the study and scientific explanation of nature theory of Chinese herbal medicine.%中药药性理论是中医药理论体系中的重要组成部分,中药药性理论的物质基础研究一直是中医药科学研究领域中的热点,也面临一些困境.本文在中药药性“性-效-物质三元论”假说基础上,进一步探讨中药药性及其成分结构之间的关联关系,提出中药“性-构关系”研究的构想,讨论在分子结构层次利用系统论的思想与信息论的科学方法从宏观角度解析中药药性,以期从中药“性-构关系”研究中探索寒热药性成分要素表征体系的构建,并对其研究方法做了分析.研究结果显示,Gibbs Free Energy等结构参数与中药寒热药性间存在非常强的关联关系,提示中药药性与相关成分的结构之间可能存在一定的关联关系,从中药“性-构关系”探索构建寒

  4. CHEMICAL TOXICITY OF URANIUM

    OpenAIRE

    2007-01-01

    Uranium, occurs naturally in the earth’s crust, is an alpha emitter radioactive element from the actinide group. For this reason, U-235 and U-238, are uranium isotopes with long half lives, have got radiological toxicity. But, for natural-isotopic-composition uranium (NatU), there is greater risk from chemical toxicity than radiological toxicity. When uranium is get into the body with anyway, also its chemical toxicity must be thought. [TAF Prev Med Bull 2007; 6(3.000): 215-220

  5. CHEMICAL TOXICITY OF URANIUM

    Directory of Open Access Journals (Sweden)

    Sermin Cam

    2007-06-01

    Full Text Available Uranium, occurs naturally in the earth’s crust, is an alpha emitter radioactive element from the actinide group. For this reason, U-235 and U-238, are uranium isotopes with long half lives, have got radiological toxicity. But, for natural-isotopic-composition uranium (NatU, there is greater risk from chemical toxicity than radiological toxicity. When uranium is get into the body with anyway, also its chemical toxicity must be thought. [TAF Prev Med Bull 2007; 6(3.000: 215-220

  6. Study on Chemical Compositions and Infrared Absorption Spectra of Natural and Synthetic Emeralds%天然祖母绿与合成祖母绿的成分及红外吸收光谱研究

    Institute of Scientific and Technical Information of China (English)

    申柯娅

    2011-01-01

    祖母绿是一种高档名贵的宝石,其矿物学名称为绿柱石,化学成分为铍铝硅酸盐.鉴别天然祖母绿和人工合成祖母绿,已成为祖母绿宝石鉴定中的一个重要课题.文章采用常规宝石学研究方法、激光剥蚀-电感耦合等离子体质谱法和红外光谱技术对天然祖母绿(包括哥伦比亚祖母绿和巴西祖母绿)、合成祖母绿(包括助熔剂法合成祖母绿和水热法合成祖母绿)样品进行了系统的分析和研究.结果表明,天然祖母绿与合成祖母绿的主要致色微量元素Cr的含量越高,祖母绿的绿色越浓艳;天然祖母绿与合成祖母绿的红外吸收光谱特征具有明显的差异;根据祖母绿中是否含水、水的赋存状态以及氯的吸收峰,可作为准确鉴别天然祖母绿和合成祖母绿的重要依据.等离子体质谱法化学成分分析不能确定祖母绿是天然形成还是人工合成,需在常规宝石学检测的基础上,综合研究祖母绿的红外吸收光谱特征及内含物特征,才能准确地鉴别天然祖母绿、水热法合成祖母绿和助熔剂法合成祖母绿.%As a top-grade and rare gemstone, emerald is a variety of the mineral beryl with the chemical composition Be3 Al2 (SiO3) 6. It is a significant research project to identify natural emerald as opposed to synthetic emerald. The routine gemological methods, laser ablation-inductively coupled plasma mass spectrometry ( LA-ICP-MS) and Fourier Transform Infrared Spectroscopy (FTIR) absorption techniques were used to study natural emeralds from Colombia and Brazil and synthetic emeralds made by flux-grown and hydrothermal synthetic methods. The green color of emerald was closely related to the concentration of the trace element Cr( Ⅲ). The infrared absorption spectra characteristics indicated obvious differences between natural and synthetic emeralds. This technique can provide important information for identifying natural and synthetic emeralds, combined

  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. 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)

    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 CCl4 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

  9. 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

  10. Chemical use

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a summary of research and activities related to chemical use on Neal Smith National Wildlife Refuge between 1992 and 2009. The chemicals used on the Refuge...

  11. Chemical Reactors.

    Science.gov (United States)

    Kenney, C. N.

    1980-01-01

    Describes a course, including content, reading list, and presentation on chemical reactors at Cambridge University, England. A brief comparison of chemical engineering education between the United States and England is also given. (JN)

  12. 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.

  13. Overall View of Chemical and Biochemical Weapons

    OpenAIRE

    Vladimír Pitschmann

    2014-01-01

    This article describes a brief history of chemical warfare, which culminated in the signing of the Chemical Weapons Convention. It describes the current level of chemical weapons and the risk of using them. Furthermore, some traditional technology for the development of chemical weapons, such as increasing toxicity, methods of overcoming chemical protection, research on natural toxins or the introduction of binary technology, has been described. In accordance with many parameters, chemical we...

  14. Chemical Leukoderma.

    Science.gov (United States)

    Bonamonte, Domenico; Vestita, Michelangelo; Romita, Paolo; Filoni, Angela; Foti, Caterina; Angelini, Gianni

    2016-01-01

    Chemical leukoderma, often clinically mimicking idiopathic vitiligo and other congenital and acquired hypopigmentation, is an acquired form of cutaneous pigment loss caused by exposure to a variety of chemicals that act through selective melanocytotoxicity. Most of these chemicals are phenols and aromatic or aliphatic catechols derivatives. These chemicals, however, are harmful for melanocytes in individuals with an individual susceptibility. Nowadays, chemical leukoderma is fairly common, caused by common domestic products. The presence of numerous acquired confetti- or pea-sized macules is clinically characteristic of chemical leukoderma, albeit not diagnostic. Other relevant diagnostic elements are a history of repeated exposure to a known or suspected depigmenting agent at the sites of onset and a macules distribution corresponding to sites of chemical exposure. Spontaneous repigmentation has been reported when the causative agent is avoided; the repigmentation process is perifollicular and gradual, taking place for a variable period of weeks to months. PMID:27172302

  15. Biochemical and Molecular Characterization of a Serine Keratinase from Brevibacillus brevis US575 with Promising Keratin-Biodegradation and Hide-Dehairing Activities

    OpenAIRE

    Nadia Zaraî Jaouadi; Hatem Rekik; Abdelmalek Badis; Sahar Trabelsi; Mouna Belhoul; Amina Benkiar Yahiaoui; Houda Ben Aicha; Abdessatar Toumi; Samir Bejar; Bassem Jaouadi

    2013-01-01

    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...

  16. 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.

  17. 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”.

  18. Chemical networks*

    OpenAIRE

    Thi Wing-Fai

    2015-01-01

    This chapter discusses the fundamental ideas of how chemical networks are build, their strengths and limitations. The chemical reactions that occur in disks combine the cold phase reactions used to model cold molecular clouds with the hot chemistry applied to planetary atmosphere models. With a general understanding of the different types of reactions that can occur, one can proceed in building a network of chemical reactions and use it to explain the abundance of species seen in disks. One o...

  19. 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

  20. Chemical Evolution in Omega Centauri

    OpenAIRE

    Smith, Verne V.

    2003-01-01

    The globular cluster Omega Centauri displays evidence of a complex star formation history and peculiar internal chemical evolution, setting it apart from essentially all other globular clusters of the Milky Way. In this review we discuss the nature of the chemical evolution that has occurred within Omega Cen and attempt to construct a simple scenario to explain its chemistry.

  1. Errors in Chemical Sensor Measurements

    Directory of Open Access Journals (Sweden)

    Artur Dybko

    2001-06-01

    Full Text Available Various types of errors during the measurements of ion-selective electrodes, ionsensitive field effect transistors, and fibre optic chemical sensors are described. The errors were divided according to their nature and place of origin into chemical, instrumental and non-chemical. The influence of interfering ions, leakage of the membrane components, liquid junction potential as well as sensor wiring, ambient light and temperature is presented.

  2. Chemical sensors

    Science.gov (United States)

    Lowell, J.R. Jr.; Edlund, D.J.; Friesen, D.T.; Rayfield, G.W.

    1991-07-02

    Sensors responsive to small changes in the concentration of chemical species are disclosed. The sensors comprise a mechanochemically responsive polymeric film capable of expansion or contraction in response to a change in its chemical environment. They are operatively coupled to a transducer capable of directly converting the expansion or contraction to a measurable electrical response. 9 figures.

  3. Chemical Radioprotectors

    Directory of Open Access Journals (Sweden)

    S. N. Upadhyay

    2005-10-01

    Full Text Available Protection of biological systems against radiation damage is of paramount importance during accidental and unavoidable exposure to radiation. Several physico-chemical and biological factors collectively contribute to the damage caused by radiation and are, therefore, targets for developing radioprotectors. Work on the development of chemicals capable of protecting biological systemsfrom radiation damage was initiated nearly six decades ago with cysteine being the first molecule to be reported. Chemicals capable of scavenging free radicals, inducing oxygen depletion,antioxidants and modulators of immune response have been some of the radioprotectors extensively investigated with limited success. Mechanism of action of some chemical radioprotectors and their combinations have been elucidated, while further understanding is required in many instances. The present review elaborates on structure-activity relationship of some of the chemical radioprotectors, their evaluation, and assessment, limitation, and future prospects.

  4. 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.

  5. 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

  6. Effect of Fresh-keeping Microorganism, Brevibacillus brevis, on Retaining Fruit Freshness under High Temperature and Humidity%保鲜功能微生物对不同鲜切水果保鲜效果的研究

    Institute of Scientific and Technical Information of China (English)

    车建美; 郑雪芳; 林抗美; 刘波

    2011-01-01

    A Fresh-keeping microorganism, Brevibacillus brevis, was isolated from the rhizosphere soil of watermelon and identified by Institute of Microbiology, Chinese Academy of Sciences, which was used for producing the product of “GUO LI XIAN”. The effect of “GUO LI XIAN” on preventing the decay of fresh fruits under high temperature and humidity was studied to Taiwan Green-jujube, Longan, Watermelon, Apple, Pear and Strawberry. Decay rates of various fruits treated by the product were differed from 32.67% to 72. 72% while related control was 100%. Initial decaying observed in fruits was postponed by treatment for about 1 or 2 days. Their weight loss rates were decreased from 1.14% to 24.90% while the control was from 4. 8% to 29.63% relatively. Results suggest that the effect of “GUO LI XIAN” on keeping fruit sensory quality was result of inhibiting pathogenic growth and maintaining the total soluble solid.%从西瓜根际土壤中分离得到保鲜功能微生物,经中科院微生物研究所鉴定为短短芽孢杆菌(Brevibacillus brevis),生产出微生物保鲜剂"果立鲜",孢子含量为10×108CFU·mL-1,稀释50倍后将其喷施于不同水果上进行保鲜效果观察.结果表明,在高温高湿条件下,"果立鲜"对龙眼、台湾大青枣、西瓜、苹果、皇冠梨和草莓具有一定的保鲜效果,降低不同水果的腐烂率,当对照组腐烂率为100%时,处理组不同水果的腐烂率在32.67%~72.72%之间.同时,"果立鲜"可将不同水果的腐烂时间推迟1~2 d,降低果实失重率,当对照组失重率在29.63%~4.8%之间时,处理组的在24.90%~1.14%之间."果立鲜"还可抑制台湾大青枣、西瓜、草莓和龙眼果实表面霉菌的生长,维持不同水果可溶性固形物含量和果实硬度,保持果实感官品质.

  7. Chemical Peels

    Science.gov (United States)

    ... pills, who subsequently become pregnant or have a history of brownish facial discoloration. Scarring Reactivation of cold sores What can I expect after having a chemical peel? All peels require some follow-up care: ...

  8. Unnecessary Chemicals

    Science.gov (United States)

    Johnson, Anita

    1978-01-01

    Discusses the health hazards resulting from chemical additions of many common products such as cough syrups, food dyes, and cosmetics. Steps being taken to protect consumers from these health hazards are included. (MDR)

  9. Amostragem e variabilidade espacial de atributos químicos do solo em área de vegetação natural em regeneração Sampling and spatial variability of chemical attributes of a soil under regenerating natural vegetation

    Directory of Open Access Journals (Sweden)

    Julião Soares de Souza Lima

    2010-02-01

    Full Text Available Este trabalho teve como objetivos estimar o número de subamostras de solo, considerando-se métodos de estatística clássica e geoestatística, e determinar a variabilidade espacial dos atributos de fertilidade de um Argissolo Vermelho-Amarelo, textura argilosa, em uma área de vegetação natural em processo de regeneração, no Município de Alegre, ES. Amostras de solo foram coletadas na profundidade de 0-0,20 m, nos pontos de cruzamento de uma malha com intervalos regulares de 10 m, perfazendo um total de 64 pontos. Observouse baixo nível de fertilidade do solo. Considerando uma variação de 5% em torno da média no método da estatística clássica, necessita-se de maior número de amostras em relação à geoestatística. Todos os atributos químicos apresentaram dependência espacial de moderada a alta, com exceção da capacidade efetiva de troca catiônica (CTCe, que apresentou efeito pepita puro. O modelo de semivariograma que mais se ajustou aos dados foi o esférico. Os mapas de isolinhas permitiram visualizar a distribuição espacial diferenciada dos teores dos atributos químicos do solo.The objectives of this work was to estimate the number of soil subsamples considering the classical statistics and geostatistics and determine the spatial variability of soil fertility attributes of an Ultisol, with clay texture, in an area of regenerating natural vegetation in Alegre - ES. Soil samples were collected in a depth of 0.0-0.2 m, at the crossing points of a regular grid, comprising a total of 64 points located at 10 m-intervals. The area presented low fertility soil. Considering a variation of 5% around the mean in the classic statistics, it is necessary a larger number of samples in relation to geostatistics. All the chemical attributes showed moderate to high spatial dependence, except for the effective cation exchange capacity (CECe, which showed pure nugget effect. The spherical semivariogram model gave the best fit to the

  10. 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

  11. Impacts of Close-to-Nature Management on Soil Chemical Properties of Korean Pine Forest in Northeastern China%近自然经营技术对红松林土壤化学性质的影响

    Institute of Scientific and Technical Information of China (English)

    吴瑶; 李凤日; 秦凯伦; 张明华; 张金富

    2014-01-01

    以“近自然林业”为指导思想,对凉水自然保护区早期做过林隙透光试验的红松人工林的土壤化学性质进行分析,同时与红松天然林、红松人工纯林、红松人工针阔叶混交林的土壤化学性质进行对比研究。结果表明:林隙透光抚育有利于提高土壤中各养分的质量分数,林隙透光试验地(土壤深度0<H≤20cm)的水解氮、速效磷、速效钾、全氮和全磷的质量分数分别为640.28 mg· kg-1、7.54 mg· kg-1、275.91 mg· kg-1、1.114%和0.075%,与其他林分相比都是最高的,且为平均值的1.1、1.4、1.3、1.6、1.2倍;对于同一林分类型的红松林来说,不同层次的土壤养分存在着明显的差异,由0<H≤20 cm到20 cm<H≤40 cm,土壤各养分指标都呈现不同程度的下降趋势,其中,下降幅度最大的是有机质质量分数,下降了170.64%,下降幅度最小的是pH值,下降了4.66%。%With “close-to-nature forestry” theory, the experiment was conducted to analyze the soil chemical properties of Kore-an pine ( Pinus koraiensis) plantation forest by crevice diaphanous tending experiment in Liangshui Nature Reserve and compare the results with those of nature Korean pine forest, artificial pure Korean pine forest, Korean pine planatation and the broadleaved mixed forest.The nurture of forestry crevice diaphanous tending can improve the soil nutrient contents and significant differences of soil nutrients in different levels of soil for the same forest type of Korean pine.At 0

  12. RECONSTRUCTION OF THUMB OPPOSITION FUNCTION BY TRANSFERRING EXTENSOR CARPI ULNARIS AND EXTENSOR POLLICIS BREVIS MUSCLE TENDONS%尺侧腕伸肌联合拇短伸肌腱转移重建拇指对掌功能

    Institute of Scientific and Technical Information of China (English)

    崔岩; 李均; 陈波; 童哲

    2011-01-01

    目的 评价尺侧腕伸肌联合拇短伸肌腱转移重建拇指对掌功能的临床疗效. 方法 2006年3月-2009年8月,采用尺侧腕伸肌联合拇短伸肌腱转移重建20例单纯腕部正中神经损伤、15例正中神经合并尺神经损伤患者的拇指对掌功能.其中男25例,女10例;年龄20~53岁,平均33.5岁.致伤原因:锐器伤24例,钝器伤9例,热压伤2例.合并尺、桡骨远端骨折6例.患者均于伤后1~3 h行神经修复术,平均2 h.受伤至该次入院时间为6~14个月,平均7.5个月.35例患者除2例单纯正中神经损伤拇外展功能不完全消失、尢对掌功能外,其余拇外展及主动对掌功能完全消失. 结果 术后切口均Ⅰ期愈合.患者均获随访,随访时间12~18个月,平均14个月.腕关节屈伸、拇指末节背伸活动正常.20例单纯正中神经损伤患者均恢复正常拇外展及对掌功能.15例合并尺神经损伤患者中,13例恢复正常对掌功能,2例对掌功能不全;拇外展功能均恢复良好.术后12个月,根据赵书强等拇指对掌功能评定标准,患者拇对掌功能测量值均在正常范围. 结论 对单纯正中神经损伤或合并尺神经损伤患者,尺侧腕伸肌联合拇短伸肌腱转移是一种操作简便且有效的手术方法.%Objective To evaluate the results of thumb opposition function by transferring the extensor carpi ulnaris and the extensor pollicis brevis muscle tendons.Methods Between March 2006 and August 2009, 35 patients with dysfunction of thumb opposition were treated and the thumb opposition function was reconstruced by transferring the extensor carpi ulnaris and the extensor pollicis brevis muscle tendons.There were 25 males and 10 females with an average age of 33.5 years (range, 20-53 years); 20 had median nerve injury in the wrist and 15 had median nerve injury with ulnar nerve injury.The causes were sharp instrument injury in 24 cases, blunt injury in 9 cases, and hot crush injury in 2 cases

  13. Natural food additives: Quo vadis?

    OpenAIRE

    Carocho, Márcio; Morales, Patricia; Isabel C. F. R. Ferreira

    2015-01-01

    In a time where the public is more aware and interested with what they eat, natural additives have been gaining interest both from the food industries and the consumers. Some studies show that consumers prefer food prepared with natural additives rather than chemical ones, due to health reasons. Although quite promising, natural additives still face some drawbacks and limitations as well as conflicting information. In this manuscript, the most important natural additives are overviewed, as we...

  14. [Cutaneous absorption of chemicals].

    Science.gov (United States)

    Schröder, J

    1986-09-01

    Chemicals have become indispensible for the maintenance of health in animals and man. The route of administration of each medicament is decided by factors such as site of desired action, chemistry of the active ingredient, age and species of the patient, and frequency of administration (or desired duration of activity). In situations where the oral and hypodermic routes, which are used most frequently, are inadequate or unsatisfactory, dermal application can provide a valuable alternative method to achieve systemic activity. Examples of formulations currently available for dermal application contain diverse chemicals and are intended for a variety of purposes, such as crufomate against cattle grubs, fenthion against cattle lice, levamisole against gastrointestinal nematodes, nitroglycerine for angina pectoris, and scopolamine for motion sickness. The skin acts as a barrier to penetration by chemicals and micro-organisms by virtue of its morphology and chemical composition. Chemicals which do penetrate, do not necessarily pass through the appendages (hair follicles and gland ducts), but mostly penetrate through the interjacent epidermis, either through the cells, or via the intracellular spaces. These spaces have recently been shown by electron microscopy to be filled by an amorphous substance which exudes on the skin surface in convex ridges. This substance has a lipid nature, but is not hydrophobic as is often accepted. For a chemical to be able to penetrate the skin, it must be partially water and lipid soluble, polar, and weakly ionizing. A variety of factors can possibly affect the permeability of skin for a chemical. These include species differences in morphology (skin thickness, tightness of intercellular junctions, density of hair follicles and other appendages), biochemistry, and physiology; seasonal and climatic variations; and differences between breeds and genders. Species differences in skin permeability are largely unpredictable and inconsistent. An

  15. Biofouling: lessons from nature.

    Science.gov (United States)

    Bixler, Gregory D; Bhushan, Bharat

    2012-05-28

    Biofouling is generally undesirable for many applications. An overview of the medical, marine and industrial fields susceptible to fouling is presented. Two types of fouling include biofouling from organism colonization and inorganic fouling from non-living particles. Nature offers many solutions to control fouling through various physical and chemical control mechanisms. Examples include low drag, low adhesion, wettability (water repellency and attraction), microtexture, grooming, sloughing, various miscellaneous behaviours and chemical secretions. A survey of nature's flora and fauna was taken in order to discover new antifouling methods that could be mimicked for engineering applications. Antifouling methods currently employed, ranging from coatings to cleaning techniques, are described. New antifouling methods will presumably incorporate a combination of physical and chemical controls.

  16. 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…

  17. 海南霸王岭五唇兰生境土壤特性分析%Soil Physical and Chemical Properties in Phalaenopsis pulcherrima (Orchidaceae) Habitat in Bawangling Natural Reserve, Hainan Island

    Institute of Scientific and Technical Information of China (English)

    杨琪; 宋希强; 胡新文; 朱国鹏

    2013-01-01

    The soil is the matric which can directly impact on the growth and development of plants, hi order to uncover the characteristics of soil in Phalaenopsis pulcherrima habitats and the difference between the two different ecotypes distributed, we set six quadrats in Bawangling nature reserve in Hainan island, where there are P. pulcherrima. We analyzed the water content, pH and contents of nitrogen, phosphorus and potassium of each soil sample, we also classified size index of P. pulcherrima individuals according to clonal ramets and biological properties, which indicates the plant biomass. We also analyzed correlation size index and the characteristics of soil, and compared these physical and chemical properties between the two ecotypes. The results revealed that the soil was acidic and rich in nutrient contents. There are remarkable difference in physical and chemical properties between different samples; and there are also difference in size index of P. pulcherrima between different quadrats. Besides, size index and soil properties showed positive correlation. All the indexes of the soil sample which P. pulcherrima grew in with red leaf dorsal are higher than that with green leaf dorsal. These results may have important value for guiding cultivation of tissue culture seedling and exploring spatial-temporal dynamics of P. pulcherrima population.%土壤是植物生长繁殖的重要环境因子,直接影响着植物的生长发育.本研究旨在揭示五唇兰自然分布区域土壤理化性质及五唇兰生态型的相关性.在海南霸王岭王下设置6个样方,测定其内土壤含水量、pH值、氮磷钾含量等理化指标;根据五唇兰的克隆分株特性和生物学特性建立五唇兰龄级指数,并分析龄级指数与土壤的相关性;比较五唇兰两种生态型其生境土壤的理化指标.结果表明:五唇兰样方内的土壤呈酸性,有机质含量较高,氮、磷、钾营养成分丰富.五唇兰根系附近的土壤理化

  18. Chemical Mahjong

    Science.gov (United States)

    Cossairt, Travis J.; Grubbs, W. Tandy

    2011-01-01

    An open-access, Web-based mnemonic game is described whereby introductory chemistry knowledge is tested using mahjong solitaire game play. Several tile sets and board layouts are included that are themed upon different chemical topics. Introductory tile sets can be selected that prompt the player to match element names to symbols and metric…

  19. Chemical Peels

    Science.gov (United States)

    ... resources Meet our partners Español Donate Diseases and treatments Acne and rosacea Bumps and growths Color problems Contagious skin diseases ... Chemical peels public SPOT Skin Cancer™ Diseases and treatments Acne and rosacea Bumps and growths Color problems Contagious skin diseases ...

  20. Chemical pressure

    OpenAIRE

    Hauser, Andreas; Amstutz, Nahid; Delahaye, Sandra; Sadki, Asmaâ; Schenker, Sabine; Sieber, Regula; Zerara, Mohamed

    2002-01-01

    The physical and photophysical properties of three classic transition metal complexes, namely [Fe(bpy)3]2+, [Ru(bpy)3]2+, and [Co(bpy)3]2+, can be tuned by doping them into a variety of inert crystalline host lattices. The underlying guest-host interactions are discussed in terms of a chemical pressure.

  1. 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 biodeg

  2. Aproveitamento sustentável de biomassa e de recursos naturais na inovação química Sustainable use fo biomass and natural resources for chemical innovation

    OpenAIRE

    Fernando Galembeck; César Augusto Sales Barbosa; Rafael Arromba Sousa

    2009-01-01

    Increased production of biomass is currently the only immediately accessible alternative for large-scale carbon sequestration and it can produce large amounts of food, fuel and raw materials for the chemical industry that can in turn growingly replace oil as a source of organic building blocks and also of hydrogen and sulfur. Development of processes for biomass and abundant minerals transformation into chemical raw materials should now benefit from large inputs from nanotechnologies, biotech...

  3. Metabolomics in chemical ecology.

    Science.gov (United States)

    Kuhlisch, Constanze; Pohnert, Georg

    2015-07-01

    Chemical ecology elucidates the nature and role of natural products as mediators of organismal interactions. The emerging techniques that can be summarized under the concept of metabolomics provide new opportunities to study such environmentally relevant signaling molecules. Especially comparative tools in metabolomics enable the identification of compounds that are regulated during interaction situations and that might play a role as e.g. pheromones, allelochemicals or in induced and activated defenses. This approach helps overcoming limitations of traditional bioassay-guided structure elucidation approaches. But the power of metabolomics is not limited to the comparison of metabolic profiles of interacting partners. Especially the link to other -omics techniques helps to unravel not only the compounds in question but the entire biosynthetic and genetic re-wiring, required for an ecological response. This review comprehensively highlights successful applications of metabolomics in chemical ecology and discusses existing limitations of these novel techniques. It focuses on recent developments in comparative metabolomics and discusses the use of metabolomics in the systems biology of organismal interactions. It also outlines the potential of large metabolomics initiatives for model organisms in the field of chemical ecology.

  4. 牛奶中分离的乳酸菌GGMCC1306中谷氨酸脱羧酶的分离纯化及酶学性质研究%Purification and Characterization of Glutamate Decarboxylase of Lactobacillus brevis CGMCC 1306 Isolated from Fresh Milk

    Institute of Scientific and Technical Information of China (English)

    黄俊; 梅乐和; 盛清; 姚善泾; 林东强

    2007-01-01

    A Lactobacillus brevis CGMCC 1306 isolated from fresh milk without pasteurization was found to have higher glutamate decarboxylase (GAD) activity. An effective isolation and purification procedure of GAD from a cell-free extract of Lactobacillus brevis was developed, and the procedure included four steps: 30%-90% saturation (NH4)2SO4 fractional precipitation,Q sepharose FF anion-exchange chromatography,sephacryl S-200 gel filtration,and resource Q anion-exchange chromatography.Using this protocol,the purified GAD was demonstrated to possess electrophoretic homogeneity via SDS-PAGE. The purificaton fold and activity recovery of GAD were 43.78 and 16.95%, respectively. The molecular weight of the purified GAD was estimated to be approximately 62 kDa via SDS-PAGE. The optimum pH and temperature of the purified GAD were 4.4 and 37℃,respecively.The purified GAD had a half-life of 50minat 45℃ and the Km value of the enzyme from Lineweaver-Burk polt was found to be 8.22.5'-pyridoxal phosphate (PLP) had little effect on the regulation of its activity.

  5. ERDA's Chemical Energy Storage Program

    Science.gov (United States)

    Swisher, J. H.; Kelley, J. H.

    1977-01-01

    The Chemical Energy Storage Program is described with emphasis on hydrogen storage. Storage techniques considered include pressurized hydrogen gas storage, cryogenic liquid hydrogen storage, storage in hydride compounds, and aromatic-alicyclic hydrogen storage. Some uses of energy storage are suggested. Information on hydrogen production and hydrogen use is also presented. Applications of hydrogen energy systems include storage of hydrogen for utilities load leveling, industrial marketing of hydrogen both as a chemical and as a fuel, natural gas supplementation, vehicular applications, and direct substitution for natural gas.

  6. Displaying Nature

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Beijing Museum of Natural History is located in Chongwen District, close to the Temple of Heaven and Tianqiao Theater. It was founded in 1951 and formally named Beijing Museum of Natural History in 1962.

  7. Natural gas

    OpenAIRE

    Bakar, Wan Azelee Wan Abu; Ali, Rusmidah

    2015-01-01

    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.

  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. Natural Products as Aromatase Inhibitors

    OpenAIRE

    Balunas, Marcy J.; Su, Bin; Brueggemeier, Robert W.; Kinghorn, A. Douglas

    2008-01-01

    With the clinical success of several synthetic aromatase inhibitors (AIs) in the treatment of postmenopausal estrogen receptor-positive breast cancer, researchers have also been investigating also the potential of natural products as AIs. Natural products from terrestrial and marine organisms provide a chemically diverse array of compounds not always available through current synthetic chemistry techniques. Natural products that have been used traditionally for nutritional or medicinal purpos...

  10. Biocatalysis for Biobased Chemicals

    Directory of Open Access Journals (Sweden)

    Rubén de Regil

    2013-10-01

    Full Text Available The design and development of greener processes that are safe and friendly is an irreversible trend that is driven by sustainable and economic issues. The use of Biocatalysis as part of a manufacturing process fits well in this trend as enzymes are themselves biodegradable, require mild conditions to work and are highly specific and well suited to carry out complex reactions in a simple way. The growth of computational capabilities in the last decades has allowed Biocatalysis to develop sophisticated tools to understand better enzymatic phenomena and to have the power to control not only process conditions but also the enzyme’s own nature. Nowadays, Biocatalysis is behind some important products in the pharmaceutical, cosmetic, food and bulk chemicals industry. In this review we want to present some of the most representative examples of industrial chemicals produced in vitro through enzymatic catalysis.

  11. Biocatalysis for biobased chemicals.

    Science.gov (United States)

    de Regil, Rubén; Sandoval, Georgina

    2013-01-01

    The design and development of greener processes that are safe and friendly is an irreversible trend that is driven by sustainable and economic issues. The use of Biocatalysis as part of a manufacturing process fits well in this trend as enzymes are themselves biodegradable, require mild conditions to work and are highly specific and well suited to carry out complex reactions in a simple way. The growth of computational capabilities in the last decades has allowed Biocatalysis to develop sophisticated tools to understand better enzymatic phenomena and to have the power to control not only process conditions but also the enzyme's own nature. Nowadays, Biocatalysis is behind some important products in the pharmaceutical, cosmetic, food and bulk chemicals industry. In this review we want to present some of the most representative examples of industrial chemicals produced in vitro through enzymatic catalysis. PMID:24970192

  12. Chemical durability of zircon

    Science.gov (United States)

    Trocellier, Patrick; Delmas, Robert

    2001-07-01

    Zircon (ZrSiO 4) exhibits a strong structural affinity for uranium and thorium together with a very high chemical durability. This makes it a potential crystalline host matrix to immobilize actinides issued from separation of nuclear wastes. Irradiation induces amorphization of the crystalline structure (the metamictization process) and thus may decrease the chemical durability of the material. Leaching tests have been conducted on natural zircons from Brazil and Madagascar at 96°C for a period of 1 month, using deionized water. Leachates have been analysed by inductively coupled plasma mass spectrometry (ICP-MS) and UV-visible spectrophotometry. Zircon solid surfaces have been investigated by coupling scanning electron microscopy and X-ray microanalysis (SEM-EDX) with nuclear microprobe analysis ( μPIXE, μRBS and μERDA). From the mass balance between leachates and hydrated surfaces, the probable mechanisms of zircon aqueous alteration are presented and discussed.

  13. Physical and Chemical Property of Forest Soil of Xishui Nature Reserve in Guizhou province%贵州习水国家级自然保护区森林土壤理化性状研究

    Institute of Scientific and Technical Information of China (English)

    吴鹏; 朱军; 陈骏; 姜霞

    2011-01-01

    在贵州习水国家级自然保护区内,根据不同的森林植被分布状况及相应海拔高度设置了13个具有代表性的标准调查样地,分别采集土壤测定其理化性状,结果表明:(1)自然保护区森林土壤容重为1.07~2.06g/cm3;土壤总孔隙度为34.9%~83.4%;森林土壤的最大蓄水量为1479.00 t.hm-2~5517.00 t.hm-2;土壤的平均初渗速率和稳渗速率分别为9.05mm.min-1和3.32mm.min-1。(2)自然保护区森林土壤主要为酸性土壤,pH值在3.72~5.97之间变动;土壤有机质的含量为74.83g/kg;土壤全N和有效N分别为2.01g/kg和215.09mg/kg;土壤的全P含量为0.33g/kg;土壤速效磷含量在1.10~84.92mg/kg之间波动,平均含量为8.02mg/kg;土壤的全K和有效K含量分别为11.81g/kg和64.37mg/kg。(3)习水自然保护区所分布的森林植被类型在改良其森林土壤的物理特性,提高土壤的贮水能力,丰富土壤有机质及其N、P、K的含量,增强和维护土壤肥力等方面都具有较显著的生态功能。%According to the distribution of forest vegetation and the corresponding elevation,13 sample plots were set in forest of Xishui Nature Reserve in Guizhou province,and assayed the physical and chemical property of the soil.The study results are as follows:⑴The soil bulk densities were 1.07~2.06g/cm3;Soil total porosities were 34.9~83.4%;Maximum water storage capacity were 1479.00 t·hm-2~5517.00 t·hm-2;The initial penetration rate and stable penetration rate were 9.05 mm·min-1 and 3.32 mm·min-1.⑵The soil pH values were 3.72~5.97;Organic matter contents were 74.83g/kg;Total nitrogen content and rapidly available content were 2.01g/kg and 215.09mg/kg;Total nitrogen phosphorus and rapidly available phosphorus were 0.33g/kg and 1.10~84.92mg/kg;Total nitrogen potassium and rapidly available potassium were 11.81g/kg and 64.37mg/kg;⑶The forests in Xishui Nature Reserve had significant ecological function on improving physical

  14. Chemical carcinogenesis

    Directory of Open Access Journals (Sweden)

    Paula A. Oliveira

    2007-12-01

    Full Text Available The use of chemical compounds benefits society in a number of ways. Pesticides, for instance, enable foodstuffs to be produced in sufficient quantities to satisfy the needs of millions of people, a condition that has led to an increase in levels of life expectancy. Yet, at times, these benefits are offset by certain disadvantages, notably the toxic side effects of the chemical compounds used. Exposure to these compounds can have varying effects, ranging from instant death to a gradual process of chemical carcinogenesis. There are three stages involved in chemical carcinogenesis. These are defined as initiation, promotion and progression. Each of these stages is characterised by morphological and biochemical modifications and result from genetic and/or epigenetic alterations. These genetic modifications include: mutations in genes that control cell proliferation, cell death and DNA repair - i.e. mutations in proto-oncogenes and tumour suppressing genes. The epigenetic factors, also considered as being non-genetic in character, can also contribute to carcinogenesis via epigenetic mechanisms which silence gene expression. The control of responses to carcinogenesis through the application of several chemical, biochemical and biological techniques facilitates the identification of those basic mechanisms involved in neoplasic development. Experimental assays with laboratory animals, epidemiological studies and quick tests enable the identification of carcinogenic compounds, the dissection of many aspects of carcinogenesis, and the establishment of effective strategies to prevent the cancer which results from exposure to chemicals.A sociedade obtém numerosos benefícios da utilização de compostos químicos. A aplicação dos pesticidas, por exemplo, permitiu obter alimento em quantidade suficiente para satisfazer as necessidades alimentares de milhões de pessoas, condição relacionada com o aumento da esperança de vida. Os benefícios estão, por

  15. Aproveitamento sustentável de biomassa e de recursos naturais na inovação química Sustainable use fo biomass and natural resources for chemical innovation

    Directory of Open Access Journals (Sweden)

    Fernando Galembeck

    2009-01-01

    Full Text Available Increased production of biomass is currently the only immediately accessible alternative for large-scale carbon sequestration and it can produce large amounts of food, fuel and raw materials for the chemical industry that can in turn growingly replace oil as a source of organic building blocks and also of hydrogen and sulfur. Development of processes for biomass and abundant minerals transformation into chemical raw materials should now benefit from large inputs from nanotechnologies, biotechnologies, information and micro-reactor technologies. Success in R&D&Innovation along this line can yield new products and processes needed to perform desirable functions within a sustainable development paradigm.

  16. Chemical cosmology

    CERN Document Server

    Boeyens, Jan CA

    2010-01-01

    The composition of the most remote objects brought into view by the Hubble telescope can no longer be reconciled with the nucleogenesis of standard cosmology and the alternative explanation, in terms of the LAMBDA-Cold-Dark-Matter model, has no recognizable chemical basis. A more rational scheme, based on the chemistry and periodicity of atomic matter, opens up an exciting new interpretation of the cosmos in terms of projective geometry and general relativity. The response of atomic structure to environmental pressure predicts non-Doppler cosmical redshifts and equilibrium nucleogenesis by alp

  17. 植物类中药寒热药性与有机成分化合物次级基团相关性的文献研究%Literature study on the relationship between the cold-heat nature of Chinese medicine and the secondary structure groups of chemical constituents

    Institute of Scientific and Technical Information of China (English)

    杨波; 王振国

    2012-01-01

    目的:探寻植物类中药中有机成分化合物次级基团与植物类中药寒热属性的相关性.方法:利用现有文献提供的信息资料,通过文献检索收集植物类中药化学成分信息,利用化学信息学对资料进行整理,运用多种数据统计分析与挖掘方法分析化学信息数据,建立Logistic回归方程,对植物类中药寒热属性进行判别.结果:以有机成分化合物次级基团建立的Logistic回归方程,可以对植物类中药的寒热属性进行判别.结论:植物类中药寒热药性与有机成分具有相关性.%Objectives: Study on the relationship between the cold-heat nature of Chinese medicine and the secondary structure groups of chemical constituents. Methods: Use the information from existing literatures; Collect chemical information of herbal medicine by document retrieval. Then use chemical informatics to collate the data and analyze it. Establish Logistic regression equation based on the secondary structure groups of chemical constituents. Use the regression equation to distinguish cold-heat nature of herbs. Results: The Logistic regression equation could distinguish cold and heat of herbs. Conclusion: There is a correlation between cold-heat nature of Chinese medicine and organic constituents.

  18. Naturally Full Functors in Nature

    Institute of Scientific and Technical Information of China (English)

    A. ARDIZZONI; C. MENINI; S. CAENEPEEL; G. MILITARU

    2006-01-01

    We introduce and discuss the notion of a naturally full functor. The definition is similar to the definition of a separable functor; a naturally full functor is a functorial version of a full functor,while a separable functor is a functorial version of a faithful functor. We study the general properties of naturally full functors. We also discuss when functors between module categories and between categories of comodules over a coring are naturally full.

  19. Chemical spectroscopy

    International Nuclear Information System (INIS)

    The purpose of chemical spectroscopy with neutrons is to utilize the dependence of neutron scattering cross-sections on isotope and on momentum transfer (which probes the spatial extent of the excitation) to understand fundamental and applied aspects of the dynamics of molecules and fluids. Chemical spectroscopy is divided into three energy ranges: vibrational spectroscopy, 25-500 MeV, for which much of the work is done on Be-filter analyzer instruments; low energy spectroscopy, less than 25 MeV; and high resolution spectroscopy, less than 1 MeV, which typically is performed on backscattering spectrometers. Representative examples of measurements of the Q-depenence of vibrational spectra, higher energy resolution as well as extension of the Q-range to lower values at high energy transfers, and provisions of higher sensitivities in vibrational spectroscopy are discussed. High resolution, high sensitivity, and polarization analysis studies in low energy spectroscopy are discussed. Applications of very high resolution spectroscopy are also discussed

  20. Ars longa, vita brevis... / Leelo Tamm

    Index Scriptorium Estoniae

    Tamm, Leelo

    1998-01-01

    16. veebr. 1998 avati Aegviidu rahvamajas maalikunstnik Valdur Ohaka 65 taiesest koosnev õlimaalide näitus, kus on töid aastaist 1943-1998. Samal päeval asus manalateele teoste looja. Aegviidu olulisusest Valdur Ohaka jaoks. Kunstniku viimastest maalidest.

  1. 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...

  2. Nature pieces

    OpenAIRE

    N. Armstrong

    2013-01-01

    Nature pieces was commissioned by Plus-Minus Ensemble, and premiered at Kings Place, London. The work stems from a long-held fascination with the ways in which nature is represented and evoked in music. Specifically, the core technical concerns are addressed to idioms and topics which have historically been put to use in musical 'appeals to nature'; i.e., in constructions and evocations of the idyllic, the folkloric, the archaic, and the hieratic. Topics that are directly engaged include: ped...

  3. Apparent tunneling in chemical reactions

    DEFF Research Database (Denmark)

    Henriksen, Niels Engholm; Hansen, Flemming Yssing; Billing, G. D.

    2000-01-01

    A necessary condition for tunneling in a chemical reaction is that the probability of crossing a barrier is non-zero, when the energy of the reactants is below the potential energy of the barrier. Due to the non-classical nature (i.e, momentum uncertainty) of vibrational states this is, however...

  4. 同种异体肌腱及自体腓骨短肌重建踝关节外侧副韧带的比较%Autologous peroneus brevis and allogeneic tendon to reconstruct lateral collateral ligament of the ankle joint

    Institute of Scientific and Technical Information of China (English)

    王成伟; 郭鹏超; 王雪; 帕尔哈提; 李璐兵; 白靖平

    2015-01-01

    BACKGROUND:Autologous peroneus brevis and alogeneic tendon are often used for reconstruction of lateral colateral ligament of the ankle joint, but these two kinds of materials have different histological and biomechanical properties. OBJECTIVE:To compare the clinical effects of autologous peroneus brevis and alogeneic tendon to reconstruct lateral colateral ligament of the ankle joint. METHODS: Sixty-six patients with chronic external ankle instability caused by old injury to lateral colateral ligament of the ankle joint were enroled, aged 15-63 years. The 34 of 66 patients underwent lateral ligament reconstruction using autologous peroneus brevis and the rest 32 patients received lateral ligament reconstruction using alogeneic tendon. After reconstruction, reaction time of the peroneous brevis, talar tilt angle and anterior talar translation, visual analog scale score and the American Orthopaedic Foot and Ankle Society (AOFAS) score were compared between the two groups. RESULTS AND CONCLUSION:At the last folow-up, the visual analog scale score, tilt angle and anterior talar translation were lowered in the two groups compared with the previous (P < 0.05), and the AOFAS scores were increased significantly in the two groups (P < 0.05); the reaction time of the peroneous brevis was increased inthe autologous peroneus brevis group (P < 0.05) and decreased in the alogeneic tendon group (P < 0.05); the above-mentioned indexes had no difference between the two groups. These findings indicate that autologous peroneus brevis and alogeneic tendon have similar effects on the lateral ligament reconstruction in terms of postoperative ankle function, stability and activity levels, but the alogeneic tendon shows advantages on less trauma and shorter operation time.%背景:目前临床多采用自体腓骨短肌或同种异体肌腱移植重建踝关节外侧副韧带,但两种材料的组织学和生物力学特性不同.目的:对比自体腓骨短肌与同种异体肌腱重建

  5. Chemical intolerance

    DEFF Research Database (Denmark)

    Dantoft, Thomas Meinertz; Andersson, Linus; Nordin, Steven;

    2015-01-01

    are available, the presence of the condition can only be established in accordance to criteria definitions. Numerous modes of action have been suggested to explain CI, with the most commonly discussed theories involving the immune system, central nervous system, olfactory and respiratory systems as well...... chemical sensitivity (MCS). The symptoms reported by CI subjects are manifold, involving symptoms from multiple organs systems. In severe cases of CI, the condition can cause considerable life-style limitations with severe social, occupational and economic consequences. As no diagnostic tools for CI...... or offered health care solutions with limited or no effect, and they experience being met with mistrust and doubt by health care professionals, the social care system and by friends and relatives. Evidence-based treatment options are currently unavailable, however, a person-centered care model based...

  6. 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.

  7. Chemical composition of water extracts from shungite and shungite water

    International Nuclear Information System (INIS)

    Chemical analysis of water extracts from shungite-3 of Zagozhino deposit (Karelia) and natural water contacting with shungite rocks are done. Chemical composition and bactericide properties of shungite water are studied

  8. Antibiosis of the ferment of the endophyte Brevibacillus brevis strain 011%内生短短芽胞杆菌011菌发酵滤液抑菌活性研究

    Institute of Scientific and Technical Information of China (English)

    王宇婷; 易有金; 夏菠; 杨建奎; 曾静

    2013-01-01

    为明确短短芽胞杆菌011菌株在植物病害生物防治中的应用潜力,采用平皿打孔法测定011菌发酵滤液抗菌谱及其活性稳定性;采用孢子萌发法测定011菌发酵滤液对番茄早疫病菌最低抑菌浓度MIC及EC50;并显微观察其对番茄早疫病菌菌丝及孢子抑制作用.结果表明:011菌发酵滤液对8种植物病原真菌均有抑制作用,其中对番茄早疫病菌抑制作用较强,抑菌带宽度为5.5 mm;对番茄早疫病菌菌丝及孢子均有致畸作用;对番茄早疫病菌最低抑菌浓度MIC为30%,有效抑菌中浓度EC50为9.64%;其活性具有较好的热稳定性(100℃处理1h活性保持在95%0),耐酸性及抗紫外线(pH2.0处理及紫外20 W,30 cm照射120 min,活性保持不变).%To investigate the utilization potential of the strain 011 of Brevibacillus brevis in biocontrol of plant diseases,antibiosis spectrum and stability of its ferment were evaluated by plate-perforation method.MIC and EC50 of the ferment against Alternaria solani were determined by spore germination assay,and its inhibitive effects on both hyphae and spores of A.solani were validated by microscopy.The results suggested that the ferment of the strain 011 had an inhibitive effect on 8 fungal plant pathogens,and the strongest inhibition was observed in A.solani,with a 5.5 mm width of inhibition band.Moreover,the ferment had a teratogenic effect on both hyphae and spores of A.solani ; the MIC and EC50 were 30% and 9.64%,respectively; the ferment had considerable heat stability (with 95% bioactivity reserved after treatment at 100 ℃ for 1 h),acid tolerance and anti-UV property (bioactivity was unaffected by pre-treatment at pH2.0 or 20 W UV radiation from a distance of 30 cm for 120 min).

  9. Chemically treated kola nut pod as low-cost natural adsorbent for the removal of 2,4-dinitrophenol from synthetic wastewater: batch equilibrium, kinetic, and thermodynamic modelling studies

    OpenAIRE

    AGARRY, Samuel; OGUNLEYE, Oladipupo

    2014-01-01

    The feasibility of using chemically treated kola nut pod to remove 2,4-dinitrophenol from its aqueous solutions under batch mode was investigated. The results showed that biosorption of 2,4-dinitrophenol was dependent on initial concentration, contact time, pH, biosorbent particle size, biosorbent dosage, and temperature. The batch equilibrium biosorption data were analyzed by 2 two-parameter (Langmuir and Freundlich) and 2 three-parameter (Redlich--Peterson and Sips) adsorption isother...

  10. Effect of A Polymer Chemical Agent on Natural Settlement of Dredged Soil%一种高分子化学剂对疏浚土自然沉降的影响

    Institute of Scientific and Technical Information of China (English)

    张骞; 董志良; 鲍树峰

    2013-01-01

    在疏浚土的化学加固研究中,化学剂的加入会直接影响疏浚土的沉降过程.以不同剂量、含水量、疏浚土组成为影响因素,观测并推算了各组试样的沉降过程中泥面高度、沉降速率、孔隙比、含水量、湿密度等参数随时间的变化情况,试验研究结果表明:化学剂在沉降速率和沉降稳定时间方面有很大的提高;化学剂的作用效果,随粘粒含量增加而降低.%In the study of dredged soil being reinforced by chemical process,adding chemical agent will affect the settlement of the soil directly.As agent consumption,water content and composition of dredged soil are the affecting factors,how the parameters of each group of sample,including mud surface height,settlement velocity,void ratio,water content,wet density,change with the time was observed and calculated.The study result shows that chemical agent could improve the settlement velocity and stabilization time but its effect will decrease with increase of clay content.

  11. Nature Detectives

    Science.gov (United States)

    Harr, Natalie; Lee, Richard E.; Jr.

    2010-01-01

    Richard Louv's "Last Child in the Woods" (2008) added to a growing consensus to get children outside and experiencing nature. Using ideas from place-based education, the authors present a simple year-long project that brings science, nature, and other curriculum standards to life right in your school yard. With a focus on journaling, this project…

  12. 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…

  13. Natur formet

    DEFF Research Database (Denmark)

    Søberg, Martin

    2011-01-01

    Anmeldelse af Malene Hauxner, "Fra naturlig natur til SUPERNATUR – Europæisk landskabsarkitektur 1967-2007 set fra Danmark", Risskov: Ikaros Press, 2011.......Anmeldelse af Malene Hauxner, "Fra naturlig natur til SUPERNATUR – Europæisk landskabsarkitektur 1967-2007 set fra Danmark", Risskov: Ikaros Press, 2011....

  14. 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 exemplified by the Skjern River Restoration Project (1999-2003), one interpretation of the landscape sometimes suppresses other valid interpretations neglecting its diverse history. Landscape architecture might, however, provide an alternative approach to nature restoration that is more site specific...... 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....

  15. How to evaluate the environmental safety of plant protection products of natural origin - Proposals for decision trees for microbial, semio-chemical, and plant-derived biopesticides: version 1.0

    NARCIS (Netherlands)

    Mensink BJWG; SEC

    2004-01-01

    The environmental safety of crop protection products of natural origin (biopesticides) is to be re-evaluated within a few years' time by the European Union. Also, new biopesticides will enter the EU market, due to the increasing importance of sustainable agriculture. There is, however, almost no gui

  16. Programmability of Chemical Reaction Networks

    Science.gov (United States)

    Cook, Matthew; Soloveichik, David; Winfree, Erik; Bruck, Jehoshua

    Motivated by the intriguing complexity of biochemical circuitry within individual cells we study Stochastic Chemical Reaction Networks (SCRNs), a formal model that considers a set of chemical reactions acting on a finite number of molecules in a well-stirred solution according to standard chemical kinetics equations. SCRNs have been widely used for describing naturally occurring (bio)chemical systems, and with the advent of synthetic biology they become a promising language for the design of artificial biochemical circuits. Our interest here is the computational power of SCRNs and how they relate to more conventional models of computation. We survey known connections and give new connections between SCRNs and Boolean Logic Circuits, Vector Addition Systems, Petri nets, Gate Implementability, Primitive Recursive Functions, Register Machines, Fractran, and Turing Machines. A theme to these investigations is the thin line between decidable and undecidable questions about SCRN behavior.

  17. Chemical information science coverage in Chemical Abstracts.

    Science.gov (United States)

    Wiggins, G

    1987-02-01

    For many years Chemical Abstracts has included in its coverage publications on chemical documentation or chemical information science. Although the bulk of those publications can be found in section 20 of Chemical Abstracts, many relevant articles were found scattered among 39 other sections of CA in 1984-1985. In addition to the scattering of references in CA, the comprehensiveness of Chemical Abstracts as a secondary source for chemical information science is called into question. Data are provided on the journals that contributed the most references on chemical information science and on the languages of publication of relevant articles.

  18. Standardized chemical synthesis of Pseudomonas aeruginosa pyocyanin

    Directory of Open Access Journals (Sweden)

    Rajkumar Cheluvappa

    2014-01-01

    As we have extracted pyocyanin both from P. aeruginosa cultures, and via chemical synthesis; we know the procedural and product-quality differences. We endorse the relative ease, safety, and convenience of using the chemical synthesis described here. Crucially, our “naturally endotoxin-free” pyocyanin can be extracted easily without using infectious bacteria.

  19. Chemical Mechanism Solvers in Air Quality Models

    OpenAIRE

    Linford, John C.; Adrian Sandu; Rolf Sander; Hong Zhang

    2011-01-01

    The solution of chemical kinetics is one of the most computationally intensive tasks in atmospheric chemical transport simulations. Due to the stiff nature of the system, implicit time stepping algorithms which repeatedly solve linear systems of equations are necessary. This paper reviews the issues and challenges associated with the construction of efficient chemical solvers, discusses several families of algorithms, presents strategies for increasing computational efficiency, and gives insi...

  20. Smart Chemical Sensors: Concepts and Application

    OpenAIRE

    Udina Oliva, Sergi

    2012-01-01

    This PhD thesis introduces basic concepts of smart chemical sensors design, which are afterwards applied to a particular application: the analysis of natural gas. The thesis addresses thus two sets of objective, a first set of objectives related to the conceptual design of a smart chemical sensor using smart sensor standards: - The design of an optimal smart chemical sensor architecture - The novel combination in a working prototype of the highly complementary smart sensor stan...