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Sample records for julibrissin fabaceae electronic

  1. Identification and quantification of glycoside flavonoids in the energy crop Albizia julibrissin

    Energy Technology Data Exchange (ETDEWEB)

    Lau, C.S.; Beitle, R.R.; Clausen, E.C. [University of Arkansas, Fayetteville (United States). Department of Chemical Engineering; Carrier, D.J. [University of Arkansas, Fayetteville (United States). Department of Biological and Agricultural Engineering; Bransby, D.I. [Auburn University, AL (United States). Department of Agronomy and Soils; Howard, L.R. [University of Arkansas, Fayetteville (United States). Department of Food Science; Lay, J.O. Jr.; Liyanage, R. [University of Arkansas, Fayetteville (United States). Department of Chemistry and Biochemistry

    2007-01-15

    Oxygen radical absorbance capacity (ORAC) values showed that methanolic extracts of Albizia julibrissin foliage displayed antioxidant activity. High performance liquid chromatography (HPLC) and mass spectrometry (MS) techniques were utilized in the identification of the compounds. The analysis conformed the presence of three compounds in A. julibrissin foliage methanolic extract: an unknown quercetin derivative with mass of 610 Da, hyperoside (quercetin-3-O-galactoside), and quercitrin quercetin-3-O-rhamnoside). Fast performance liquid chromatography (FPLC) was employed to fractionate the crude A. julibrissin foliage methanolic extract into its individual flavonoid components. The flavonoids were quantified in terms of mass and their respective contribution to the overall ORAC value. Quercetin glycosides accounted for 2.0% of total foliage. (author)

  2. D-Pinitol in Fabaceae: an Oviposition Stimulant for the Common Grass Yellow Butterfly, Eurema mandarina.

    Science.gov (United States)

    Mukae, Shin-Ya; Ohashi, Toshiki; Matsumoto, Yuika; Ohta, Shinji; Ômura, Hisashi

    2016-11-01

    The common grass yellow butterfly, Eurema mandarina (formerly Eurema hecabe mandarina) (Lepidoptera, Pieridae), recently has been separated taxonomically from a subtropical population of Eurema hecabe in Japan. This species is widely distributed in the temperate region of Japan, and feeds mainly on various ligneous plants within the Fabaceae. We attempted to identify an oviposition stimulant for E. mandarina from its primary hosts, Albizia julibrissin and Lespedeza cuneata. In both hosts, crude extract and an aqueous fraction elicited oviposition responses from gravid females. A polar subfraction of the aqueous fraction also stimulated high oviposition-stimulatory activity, comparable to the original aqueous fraction, suggesting that E. mandarina females use water-soluble compounds for host recognition. Subsequent activity-directed fractionation by ion exchange chromatography indicated that one of the key substances was contained in the neutral/amphoteric fraction. Chemical analyses revealed that the active fractions of both hosts contained D-(+)-pinitol as the major component. We examined female responses to authentic D-pinitol and found that it induced oviposition responses at concentrations greater than 0.1 %. Since this cyclitol is omnipresent in Fabaceae, we conclude that D-pinitol plays a role in mediating oviposition of E. mandarina on fabaceous plants.

  3. Anti-Anxiety Effect of (-)-Syringaresnol-4-O-β-d-apiofuranosyl-(1→2)-β-d-glucopyranoside from Albizzia julibrissin Durazz (Leguminosae).

    Science.gov (United States)

    Liu, Jie; Lv, Yue-Wei; Shi, Jin-Li; Ma, Xiao-Jie; Chen, Yi; Zheng, Zhi-Quan; Wang, Sheng-Nan; Guo, Jian-You

    2017-08-11

    Albizzia julibrissin Durazz, a Chinese Medicine, is commonly used for its anti-anxiety effects. (-)-syringaresnol-4- O -β-d-apiofuranosyl-(1→2)-β-d-glucopyranoside (SAG) is the main ingredient of Albizzia julibrissin Durazz. The present study investigated the anxiolytic effect and potential mechanisms on the HPA axis and monoaminergic systems of SAG on acute restraint-stressed rats. The anxiolytic effect of SAG was examined through an open field test and an elevated plus maze test. The concentration of CRF, ACTH, and CORT in plasma was examined by an enzyme-linked immune sorbent assay (ELISA) kit while neurotransmitters in the cerebral cortex and hippocampus of the brain were examined by High Performance Liquid Chromatography (HPLC). We show that repeated treatment with SAG (3.6 mg/kg, p.o.) significantly increased the number and time spent on the central entries in the open-field test when compared to the vehicle/stressed group. In the elevated plus maze test, 3.6 mg/kg SAG could increase the percentage of entries into and time spent on the open arms of the elevated plus maze. In addition, the concentration of CRF, ACTH, and CORT in plasma and neurotransmitters (NE, 5-HT, DA and their metabolites 5-HIAA, DOPAC, and HVA) in the cerebral cortex and hippocampus of the brain were decreased after SAG treatment, as compared to the repeated acute restraint-stressed rats. These results suggest that SAG is a potential anti-anxiety drug candidate.

  4. New Records of Bruchidius Spermaphagous Species in Albizia julibrissin and Laburnum anagyroides and Their Parasitoid Complex in Serbia

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    Renata Gagić Serdar

    2014-12-01

    Full Text Available Background and Purpose: Bruchidius villosus feeding in seed of Laburnum anagyroides, and Bruchidius terrenus seed pest of Albizia julibrissin are first recorded and completely new seed-beetle to Serbian Bruchinae fauna. This Chrysomelids which were found in Republic of Serbia during intensive studies from 2012 to 2014 are likely related to a mostly Paleotropical group, including also members of genera Bruchidius, Megabruchidius and Acanthoscellides. These seed-beetles develop in pods of these two woody legumes, widely grown ornamental trees and shrubs. Several recent reports reveal that this species are well established in France, Hungary, and Bulgaria. Materials and Methods: Bruchine and their legume hosts were observed by extensive field sampling throughout Serbia over three years and by rearing the beetles from the samples in the laboratory. Bruchines and the parasitoids were mass-reared in climate controled rooms under conditions close to those of their area of origin: 12:12 L:D, 3-23 °C and ≤80 % RH (depends of host plant ongoing phenology or experimental needs-proof of weevil monophagous feeding preferences. For the purpose of analyzing the observed phenomena (its intensity and relevance, some of the standard methods of statistical analysis and conclusion have been used. Results: Levels of seeds infestation still in the pods were high and comparable to other studies. Bruchine beetle infestation in the dehiscent fruits of host plants may be greater after the seeds and pods drop to the ground, as bivoltine generation occurs, but this has yet to be tested. Hypotheses on the geographic origin of this new species are also discussed. The effect of native parasitoids occurrence could potentially be interesting, given that their appearance suggest their specialization on the Bruchidius beetle species which is a common seed-predator on the leguminous seeds. Conclusions: The establishment of this new species is investigated using both

  5. Révision du genre Eurypetalum Harms (Fabaceae, Caesalpinioideae)

    NARCIS (Netherlands)

    Obiang-Mbomio, D.; Breteler, F.J.

    2007-01-01

    Revision of the genus Eurypetalum Harms (Fabaceae, Caesalpinioideae). Th e African genus Eurypetalum Harms (Fabaceae, Caesalpinioideae) of Lower Guinea is revised. Two species, E. tessmannii and E. unijugum, are recognized. Th ey are illustrated and their distributions are mapped. Eurypetalum

  6. Screening of the anticonvulsant activity of some plants from Fabaceae family in experimental seizure models in mice

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    S Sardari

    2011-10-01

    Full Text Available "n  Background and purpose of the study: Fabaceae is the third largest family of flowering plants. Lack of essential oils in the plants of this family can be an advantage in search for safe and effective medicines. In this study the anticonvulsant effect of the leaves of Albizzia julibrissin, Acacia juliflora, Acacia nubica and aerial parts of Astragalus obtusifolius was evaluated in pentylenetetrazole (PTZ and maximal electroshock (MES seizure tests. "n  Methods: The hydroalcoholic extracts of the plants were obtained by percolation. Different doses of the extracts were injected to the mice intraperitoneally (i.p. and occurrence of clonic seizures induced by PTZ (60 mg/kg, i.p. or tonic seizures induced by MES (50 mA, 50Hz, 1sec were monitored up to 30 min after administration. Acute toxicity of the extracts was also assessed. The safe and effective extract was then fractionated by dichloromethane and anticonvulsant activity of the fractions was determined. Finally, the constituents of the extract and the fractions were screened by thin layer chromatography. "n  Results: Among the extracts, only A. obtusifolius extract showed low toxicity and protective effect against clonic seizures with ED50 value of 3.97 g/kg. Fractionation of the extract led to increase in anticonvulsant activity and ED50 value of 2.86 g/kg was obtained for the aqueous fraction. Phytochemical screening revealed the presence of alkaloids, flavonoids, anthrones and saponins in the aqueous fraction. "n  Major conclusion: The presence of anticonvulsant compounds in A. obtusifolius suggests further activity-guided fractionation and analytical studies to find out the potential of this plant as a source of anticonvulsant agent.

  7. Antraquinonas de Vatairea guianensis Aubl. (Fabaceae)

    OpenAIRE

    Piedade, Luiz Rubens; Wolter Filho, Wilson

    1988-01-01

    As antraquinonas crisofanol, fisciona, emodina e os triterpenos conhecidos como ácido oleanótico e a lactona do ácido diidromacaerinico foram isolados do extrato metanólico das cascas do caule de Vatairea guianensis Aubl., (Fabaceae). A ocorrência das fis-ciona e da forma lactônica do ácido diidromacaerínico no gênero Vataireanão havia ainda sido descrita na literatura. The metanolic extracts from the bark of Vatairea guianensis Aubl. (Fabaceae) yieded physcion, emodin, chrysophanol, oleoa...

  8. Molecular systematics of Indian Alysicarpus (Fabaceae) based

    Indian Academy of Sciences (India)

    Alysicarpus Necker ex Desvaux (Fabaceae, Desmodieae) consists of ∼30 species that are distributed in tropical and subtropical regions of theworld. In India, the genus is represented by ca. 18 species, ofwhich seven are endemic. Sequences of the nuclear Internal transcribed spacer from38 accessions representing 16 ...

  9. Volatile constituents from Samanae saman (Jacq.) Merr. Fabaceae

    African Journals Online (AJOL)

    AJB SERVER

    2006-10-16

    Oct 16, 2006 ... Key words: Samanae saman, Fabaceae, volatile oil, fatty acids, terpenoids, palmitic acid, 1,8-cineole. .... Gas chromatography – mass spectrometry analyses (GC/MS) ... this study, is an important constituent of most vegetable.

  10. Hierarchical traits distances explain grassland Fabaceae species' ecological niches distances

    Science.gov (United States)

    Fort, Florian; Jouany, Claire; Cruz, Pablo

    2015-01-01

    Fabaceae species play a key role in ecosystem functioning through their capacity to fix atmospheric nitrogen via their symbiosis with Rhizobium bacteria. To increase benefits of using Fabaceae in agricultural systems, it is necessary to find ways to evaluate species or genotypes having potential adaptations to sub-optimal growth conditions. We evaluated the relevance of phylogenetic distance, absolute trait distance and hierarchical trait distance for comparing the adaptation of 13 grassland Fabaceae species to different habitats, i.e., ecological niches. We measured a wide range of functional traits (root traits, leaf traits, and whole plant traits) in these species. Species phylogenetic and ecological distances were assessed from a species-level phylogenetic tree and species' ecological indicator values, respectively. We demonstrated that differences in ecological niches between grassland Fabaceae species were related more to their hierarchical trait distances than to their phylogenetic distances. We showed that grassland Fabaceae functional traits tend to converge among species with the same ecological requirements. Species with acquisitive root strategies (thin roots, shallow root systems) are competitive species adapted to non-stressful meadows, while conservative ones (coarse roots, deep root systems) are able to tolerate stressful continental climates. In contrast, acquisitive species appeared to be able to tolerate low soil-P availability, while conservative ones need high P availability. Finally we highlight that traits converge along the ecological gradient, providing the assumption that species with similar root-trait values are better able to coexist, regardless of their phylogenetic distance. PMID:25741353

  11. Hierarchical traits distances explain grassland Fabaceae species’ ecological niches distances

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    Florian eFort

    2015-02-01

    Full Text Available Fabaceae species play a key role in ecosystem functioning through their capacity to fix atmospheric nitrogen via their symbiosis with Rhizobium bacteria. To increase benefits of using Fabaceae in agricultural systems, it is necessary to find ways to evaluate species or genotypes having potential adaptations to sub-optimal growth conditions. We evaluated the relevance of phylogenetic distance, absolute trait distance and hierarchical trait distance for comparing the adaptation of 13 grassland Fabaceae species to different habitats, i.e. ecological niches. We measured a wide range of functional traits (root traits, leaf traits and whole plant traits in these species. Species phylogenetic and ecological distances were assessed from a species-level phylogenetic tree and species’ ecological indicator values, respectively. We demonstrated that differences in ecological niches between grassland Fabaceae species were related more to their hierarchical trait distances than to their phylogenetic distances. We showed that grassland Fabaceae functional traits tend to converge among species with the same ecological requirements. Species with acquisitive root strategies (thin roots, shallow root systems are competitive species adapted to non-stressful meadows, while conservative ones (coarse roots, deep root systems are able to tolerate stressful continental climates. In contrast, acquisitive species appeared to be able to tolerate low soil-P availability, while conservative ones need high P availability. Finally we highlight that traits converge along the ecological gradient, providing the assumption that species with similar root-trait values are better able to coexist, regardless of their phylogenetic distance.

  12. Hydrocarbon phytoremediation in the family Fabaceae--a review.

    Science.gov (United States)

    Hall, Jessica; Soole, Kathleen; Bentham, Richard

    2011-04-01

    Currently, studies often focus on the use of Poaceae species (grasses) for phytoremediation of hydrocarbon-contaminated soils. Research into the use of Fabaceae species (legumes) to remediate hydrocarbons in soils has been conducted, but these plants are commonly overlooked due to slower recorded rates of degradation compared with many grass species. Evidence in the literature suggests that in some cases Fabaceae species may increase total degradation of hydrocarbons and stimulate degradative capacity of the soil microbial community, particularly for contaminants which are normally more recalcitrant to degradation. As many recalcitrant hydrocarbons have negative impacts on human and ecosystem health, development of remediation options is crucial. Reconsideration of Fabaceae species for removal of such contaminants may lead to environmentally and economically sustainable technologies for remediation of contaminated sites.

  13. Fatty acid profiles of some Fabaceae seed oils

    Science.gov (United States)

    The fatty acid profiles of six seed oils of the Fabaceae (Leguminosae) family are reported and discussed. These are the seed oils of Centrosema pubescens, Clitoria ternatea, Crotalaria mucronata, Macroptilium lathyroides, Pachyrhizus erosus, and Senna alata. The most common fatty acid in the fatty a...

  14. Hypoglycemic Effects of Clitoria ternatea Linn. (Fabaceae) in ...

    African Journals Online (AJOL)

    Purpose: This study aims to investigate the therapeutic effects of the aqueous extract of Clitoria ternatea Linn. Fabaceae leaves and flowers on alloxan-induced diabetes in rats. Methods: The effect of orally administered aqueous extracts (400 mg/kg body weight) of Clitoria ternatea leaves and flowers on serum glucose, ...

  15. New chromosome numbers in the genus Trigonella L. ( Fabaceae ...

    African Journals Online (AJOL)

    Somatic chromosome numbers of 45 Trigonella L. (Fabaceae), collected from different localities in Turkey was examined. Chromosome numbers were determined as 2n = 14, 16, 30 and 46. B chromosome was also observed in somatic cells of some taxa (Trigonella arcuata C.A. Meyer and Trigonella procumbens (Besser) ...

  16. Molecular and phylogenetic characterization of the sieve element occlusion gene family in Fabaceae and non-Fabaceae plants.

    Science.gov (United States)

    Rüping, Boris; Ernst, Antonia M; Jekat, Stephan B; Nordzieke, Steffen; Reineke, Anna R; Müller, Boje; Bornberg-Bauer, Erich; Prüfer, Dirk; Noll, Gundula A

    2010-10-08

    The phloem of dicotyledonous plants contains specialized P-proteins (phloem proteins) that accumulate during sieve element differentiation and remain parietally associated with the cisternae of the endoplasmic reticulum in mature sieve elements. Wounding causes P-protein filaments to accumulate at the sieve plates and block the translocation of photosynthate. Specialized, spindle-shaped P-proteins known as forisomes that undergo reversible calcium-dependent conformational changes have evolved exclusively in the Fabaceae. Recently, the molecular characterization of three genes encoding forisome components in the model legume Medicago truncatula (MtSEO1, MtSEO2 and MtSEO3; SEO = sieve element occlusion) was reported, but little is known about the molecular characteristics of P-proteins in non-Fabaceae. We performed a comprehensive genome-wide comparative analysis by screening the M. truncatula, Glycine max, Arabidopsis thaliana, Vitis vinifera and Solanum phureja genomes, and a Malus domestica EST library for homologs of MtSEO1, MtSEO2 and MtSEO3 and identified numerous novel SEO genes in Fabaceae and even non-Fabaceae plants, which do not possess forisomes. Even in Fabaceae some SEO genes appear to not encode forisome components. All SEO genes have a similar exon-intron structure and are expressed predominantly in the phloem. Phylogenetic analysis revealed the presence of several subgroups with Fabaceae-specific subgroups containing all of the known as well as newly identified forisome component proteins. We constructed Hidden Markov Models that identified three conserved protein domains, which characterize SEO proteins when present in combination. In addition, one common and three subgroup specific protein motifs were found in the amino acid sequences of SEO proteins. SEO genes are organized in genomic clusters and the conserved synteny allowed us to identify several M. truncatula vs G. max orthologs as well as paralogs within the G. max genome. The unexpected

  17. Biflavonoids and other phenolics from Caesalpinia pyramidalis (Fabaceae)

    OpenAIRE

    Bahia, Marcus V.; Santos, Jamile B. dos; David, Juceni P.; David, Jorge M.

    2005-01-01

    The chloroform extract of the leaves of Caesalpinia pyramidalis (Caesalpinioidea, Fabaceae) yielded the new biflavonoid named caesalflavone, as well as podocarpusflavone A, agathisflavone, apigenin and kaempferol. The chloroform extract of the trunk wood gave 4,4'-dihydroxy-2'-methoxychalcone, (-)-syringaresinol, and methyl gallate. Biflavonoids were not found in trunk wood. Until now, C. pyramidalis is the first species in the genus to present biflavonoids. The structural elucidation of the ...

  18. A taxonomic revision of the genus Rafnia Thunb. (Fabaceae, Crotalarieae)

    OpenAIRE

    2012-01-01

    M.Sc. A taxonomic revision of the genus Rafnia Thunb. (= Oedmannia Thunb., Vascoa DC., Pelecynthis E. Mey), a relatively poorly known papilionoid legume genus, is presented. Rafnia (family Fabaceae, tribe Crotalarieae) is subendemic to the fynbos region of the Western and Eastern Cape Provinces of South Africa, with one species having a distribution area reaching into KwaZulu-Natal. The species delimitation has been unsatisfactory, and the relationships among the taxa uncertain. Rafnia is ...

  19. 7 CFR 201.56-6 - Legume or pea family, Fabaceae (Leguminosae).

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Legume or pea family, Fabaceae (Leguminosae). 201.56-6 Section 201.56-6 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL...-6 Legume or pea family, Fabaceae (Leguminosae). Kinds of seed: Alfalfa, alyceclover, asparagusbean...

  20. Biflavonoids and other phenolics from Caesalpinia pyramidalis (Fabaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Bahia, Marcus V.; Santos, Jamile B. dos; David, Jorge M. [Bahia Univ., Salvador, BA (Brazil). Inst. de Quimica; David, Juceni P. [Bahia Univ., Salvador, BA (Brazil). Faculdade de Farmacia

    2005-11-15

    The chloroform extract of the leaves of Caesalpinia pyramidalis (Caesalpinioidea, Fabaceae) yielded the new biflavonoid named caesalflavone, as well as podocarpusflavone A, agathisflavone, apigenin and kaempferol. The chloroform extract of the trunk wood gave 4,4'-dihydroxy-2'-methoxychalcone, (-)-syringaresinol, and methyl gallate. Biflavonoids were not found in trunk wood. Until now, C. pyramidalis is the first species in the genus to present biflavonoids. The structural elucidation of the isolated compounds and their derivatives were based on MS, IR, UV, 1D and 2D NMR spectral analyses. (au)

  1. Biflavonoids and other phenolics from Caesalpinia pyramidalis (Fabaceae)

    International Nuclear Information System (INIS)

    Bahia, Marcus V.; Santos, Jamile B. dos; David, Jorge M.; David, Juceni P.

    2005-01-01

    The chloroform extract of the leaves of Caesalpinia pyramidalis (Caesalpinioidea, Fabaceae) yielded the new biflavonoid named caesalflavone, as well as podocarpusflavone A, agathisflavone, apigenin and kaempferol. The chloroform extract of the trunk wood gave 4,4'-dihydroxy-2'-methoxychalcone, (-)-syringaresinol, and methyl gallate. Biflavonoids were not found in trunk wood. Until now, C. pyramidalis is the first species in the genus to present biflavonoids. The structural elucidation of the isolated compounds and their derivatives were based on MS, IR, UV, 1D and 2D NMR spectral analyses. (author)

  2. Chemical constituents from Piptadenia rigida Benth., Fabaceae, "angico"

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    Mário G. de Carvalho

    2011-06-01

    Full Text Available The phytochemical investigation of the roots of Piptadenia rigida Benth., Fabaceae, known as "angico", afforded sitosterol, lupeol, betuline, the chalcone isoliquiritigenin, the flavonoids, 7,4'-dihydroxyflavone, 7,3',4'-trihydroxyflavone, 7,8,3',4'-tetrahydroxyflavanone, 4-hydroxy-3,5-dimethoxybenzaldehyde and methyl-3,4-dihydroxy-benzoate. Both flavones were also isolated from the branches of this plant. Five derivatives of the aldehyde were obtained by diazomethane treatment. The structures of compounds were identified by IR, NMR and mass spectral data analysis of natural compounds and some derivatives, and by comparison with literature data.

  3. Chemical constituents from Piptadenia rigida Benth., Fabaceae, "angico"

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    Mário G. de Carvalho

    2010-03-01

    Full Text Available The phytochemical investigation of the roots of Piptadenia rigida Benth., Fabaceae, known as "angico", afforded sitosterol, lupeol, betuline, the chalcone isoliquiritigenin, the flavonoids, 7,4'-dihydroxyflavone, 7,3',4'-trihydroxyflavone, 7,8,3',4'-tetrahydroxyflavanone, 4-hydroxy-3,5-dimethoxybenzaldehyde and methyl-3,4-dihydroxy-benzoate. Both flavones were also isolated from the branches of this plant. Five derivatives of the aldehyde were obtained by diazomethane treatment. The structures of compounds were identified by IR, NMR and mass spectral data analysis of natural compounds and some derivatives, and by comparison with literature data.

  4. Biflavonoids and other phenolics from Caesalpinia pyramidalis (Fabaceae)

    OpenAIRE

    Bahia, Marcus Vinicius; Santos, Jamile Batista dos; David, Juceni Pereira de Lima; David, Jorge Mauricio

    2005-01-01

    p. 1402-1405 O reestudo do extrato clorofórmico das folhas de Caesalpinia pyramidalis (Caesalpinioidea, Fabaceae) forneceu, além do novo biflavonóide denominado caesalflavona, podocarpusflavona A, agathisflavona, apigenina, kaempferol, sitosterol e lupeol. Por outro lado, a partir do extrato clorofórmico do caule foram obtidos 4, 4'-diidroxi-2'-metoxi-chalcona, (-)-siringaresinol e galato de metila. Não foram encontrados biflavonóides nesta parte da planta. Até o presente, C. pyramidalis é...

  5. Reproductive biology of Bowdichia virgilioides Kunth (Fabaceae = Biologia reprodutiva de Bowdichia virgilioides Kunth (Fabaceae

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    André Luiz Gomes da Silva

    2011-09-01

    Full Text Available The aim of this study was to investigate the reproductive biology of Bowdichia virgilioides in an area of Cerrado (Brazilian Savanna. The study was carried out in Chapadinha, State of Maranhão in northeastern Brazil. Bowdichia virgilioides has cornucopia flowering and annual pattern. Flowering occurred at the beginning of the dry season, between June and August; and fruiting in the middle of this season, between July and October. The anthesis of B. virgilioides is diurnal, and the main flower resource is the nectar. During the flower opening, the anthers becomes dehiscent and thus pollen grains are deposited at the stigma, promoting automatic selfpollination. The species is self-compatible and apomitic. In the study area, they were visited by nine species of bees, four butterflies, two wasps, and two hummingbirds. The visits began in early morning and persisted throughout the day, with a peak of activity between 8:00 and 9:00hours. Species of Centris were the main visitors of B. virgilioides. The butterfly and wasp species were considered resource robbers, and other floral visitors were considered occasional visitors. Although the flowers of B. virgilioides are widely visited, the species shows a high rate of inbreeding because of automatic self-pollination.Este trabalho teve como objetivo estudar a biologia reprodutiva de Bowdichia virgilioides Kunth (Fabaceae e avaliar o papel dos visitantes florais em seu sucesso reprodutivo. Bowdichia virgilioides apresenta padrão de floração anual e do tipo cornucópica. A floração ocorre no início da estação seca, entre os meses de junho e agosto e a frutificação no meio desta estação, entre os meses de julho e outubro. Suas flores são de antese diurna e apresentam néctar como recurso floral. Durante a abertura floral, as anteras se encontram deiscentes e por esta razão há a adesão dos grãos de pólen no estigma da própria flor, promovendo o processo de autopolinização passiva. A esp

  6. Plant antiherbivore defenses in Fabaceae species of the Chaco.

    Science.gov (United States)

    Lima, T E; Sartori, A L B; Rodrigues, M L M

    2017-01-01

    The establishment and maintenance of plant species in the Chaco, one of the widest continuous areas of forests in the South American with sharp climatic variations, are possibly related to biological features favoring plants with particular defenses. This study assesses the physical and chemical defenses mechanisms against herbivores of vegetative and reproductive organs. Its analyses of 12 species of Fabaceae (Leguminosae) collected in remnants of Brazilian Chaco shows that 75% present structural defense characters and 50% have chemical defense - defense proteins in their seeds, like protease inhibitors and lectins. Physical defenses occur mainly on branches (78% of the species), leaves (67%), and reproductive organs (56%). The most common physical characters are trichomes and thorns, whose color represents a cryptic character since it does not contrast with the other plant structures. Defense proteins occur in different concentrations and molecular weight classes in the seeds of most species. Protease inhibitors are reported for the first time in seeds of: Albizia niopoides, Anadenanthera colubrina, Mimosa glutinosa, Prosopis rubriflora, and Poincianella pluviosa. The occurrence of physical and chemical defenses in members of Fabaceae indicate no associations between defense characters in these plant species of the Chaco.

  7. Molecular systematics of selected genera of subfamily mimosoidae-fabaceae

    International Nuclear Information System (INIS)

    Shinwari, Z.K.; Jamil, K.; Zahra, N.B.

    2014-01-01

    Family Mimosoidae-Fabaceae is of economic importance to local communities for its medicinal usage. It has commercial value, but the parts sold in the market are difficult to identify on the basis of morphological characters and therefore needs molecular systematics approaches. Hence, the utility of potential DNA barcodes for selected Acacia and Albizia species by using three cpDNA regions rbcL, matK and trnH-psbA was tested in this study. Our study suggests that the rbcL region can be used to identify these species and discriminate among them more effectively than matK and trnH-psbA. The latter regions proved to be less successful in sequencing particularly trnH-psbA. Therefore, rbcL is an improved and efficient tool for species identification of these medicinal plants and may be recommended for a broad series of subfamily Mimosoideae (Family: Fabaceae) plants, making it a potential DNA barcode for these taxa. Sequence data obtained from rbcL and matK also indicated that Acacia and Albizia are polyphyletic. The phylogenetic analysis on the basis of rbcL proved that Acacia nilotica and Acacia nilotica ssp. hemispherica are closely related as they form the sister groups. (author)

  8. Checklist of Fabaceae Lindley in Balaghat Ranges of Maharashtra, India

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    Ramchandra Gore

    2015-03-01

    Full Text Available The present paper provides an enumeration of leguminous taxa of Balaghat Ranges of Maharashtra along with their habits, phenological deta and voucher specimen numbers. During the present work, a total of 123 species, 4 subspecies and 17 varieties of Fabaceae have been recorded for Balaghat Ranges of Maharashtra, of which 119 taxa are occurring in wild while 25 are under cultivation. The members of Fabaceae are dominant in herbaceous vegetation of the Balaghat Ranges. There are more species in genera like Crotalaria (23 taxa, Indigofera (16 taxa, Alysicarpus (14 taxa, Vigna (11 taxa and Desmodium (8 taxa. Twelve taxa are endemic to India of which Indigofera deccanensis falls into Critically Endangered IUCN Red data category. The legumes of Balaghat Ranges have many actual and potential uses such as food, fodder and sources of edible oil, natural dyes, industrial lubricants, timber and medicines. About 19 leguminous taxa are wild relatives of food and fodder crops have resistance to pests and diseases, and abiotic stresses such as drought and salinity, can be used for crop improvement.

  9. Identification of Fabaceae plants using the DNA barcode matK.

    Science.gov (United States)

    Gao, Ting; Sun, Zhiying; Yao, Hui; Song, Jingyuan; Zhu, Yingjie; Ma, Xinye; Chen, Shilin

    2011-01-01

    In this study, we tested the applicability of the core DNA barcode MATK for identifying species within the Fabaceae family. Based on an evaluation of genetic variation, DNA barcoding gaps, and species discrimination power, MATK is a useful barcode for Fabaceae species. Of 1355 plant samples collected from 1079 species belonging to 409 diverse genera, MATK precisely identified approximately 80 % and 96 % of them at the species and genus levels, respectively. Therefore, our research indicates that the MATK region is a valuable marker for plant species within Fabaceae. © Georg Thieme Verlag KG Stuttgart · New York.

  10. Astragalus friederikeanus Kit Tan & Zeitlinger (Fabaceae), a new species from south Anatolia, Turkey

    DEFF Research Database (Denmark)

    Tan, Kit; Zeitlinger, Jörg

    2007-01-01

    A new species from south Anatolia, Turkey, Astragalus friederikeanus Kit Tan & Zeitlinger (Fabaceae), is described and illustrated. The diagnostic morphological characters separating it from other members of sect. Onobrychium Boiss. are listed.......A new species from south Anatolia, Turkey, Astragalus friederikeanus Kit Tan & Zeitlinger (Fabaceae), is described and illustrated. The diagnostic morphological characters separating it from other members of sect. Onobrychium Boiss. are listed....

  11. Urease inhibitory isoflavonoids from different parts of Calopogonium mucunoides (Fabaceae).

    Science.gov (United States)

    Ndemangou, Brigitte; Sielinou, Valerie Tedjon; Vardamides, Juliette Catherine; Ali, Muhammad Shaiq; Lateef, Mehreen; Iqbal, Lubna; Afza, Nigaht; Nkengfack, Augustin Ephrem

    2013-12-01

    The dichloromethane-methanol (1:1) soluble part of Calopogonium mucunoides (Fabaceae) resulted in the isolation of 10 isoflavones (4'-O-methylalpinumisoflavone, 4'-O-methylderrone, alpinumisoflavone, daidzeine, Calopogonium isoflavone A, atalantoflavone, 2',4',5',7-tetramethoxyisoflavone, 7-O-methylcuneantin, cabreuvin and 7-O-methylpseudobaptigenin) and a rotenoid (6a,12a-dehydroxydegueline). Among these, daidzeine, 7-O-methylcuneantin, atalantoflavone and 6a, 12a-dehydroxydegueline have been isolated for the first time from C. mucunoides while remaining are already reported from this source. Structures of all the isolated constituents were elucidated with the aid of NMR spectroscopic and mass spectrometric techniques. Among all the isolated constituents, nine were evaluated for their urease inhibitory potential. However, six were found potent. These include 4'-O-methylderrone, daidzeine, atalantoflavone, 2',4',5',7-tetramethoxyisoflavone, 7-O-methylcuneantin and 6a, 12a-dehydroxydegueline.

  12. Pollen Viability and Autogamy Fitness in Bauhinia forficata Link (Fabaceae

    Directory of Open Access Journals (Sweden)

    Luana Camila Capitani

    2018-05-01

    Full Text Available ABSTRACT Bauhinia forficata (Fabaceae occurs in many phytophysiognomies of southern Brazil, however its ecological relevance is not well understood. The present study was developed in the Central Depression of Rio Grande do Sul and aimed to determine variations in pollen viability along flowering, ability to perform autogamy and dye efficiency for the viability test. Pollen viability was determined by colorimetry as well as the ability to perform autogamy by isolating floral buds, being evaluated in eleven matrices. Average pollen viability was 81.43%, with the highest average value obtained with the dye 2,3,5- Triphenyltetrazolium Chloride (TTC (84.11%. Safranin was not a good indicator at the tested concentration. No correlation was found between pollen viability and flowering time. The species demonstrated an inability to perform autogamy.

  13. Use of the psbA-trnH region to authenticate medicinal species of Fabaceae.

    Science.gov (United States)

    Gao, Ting; Ma, Xinye; Zhu, Xunzhi

    2013-01-01

    Fabaceae is a huge family that contains a large number of medicinal plants, many of which are commonly used in Chinese traditional medicine. However, traditional taxonomy has not been able to meet the complicated demands of species discrimination within Fabaceae. Thus, we employed a famous DNA barcode, the psbA-trnH region, to discriminate commonly used medicinal species of the family Fabaceae. Here, the psbA-trnH regions derived from 152 samples were amplified. These samples represented 104 Fabaceae medicinal species from 60 genera, including 25 authentic Fabaceae species listed in the Chinese pharmacopoeia and common adulterant species. The results indicate that the psbA-trnH region performed well in terms of its universality and high variability in length and composition. Species discriminative power analysis of the psbA-trnH region showed that 91.3% of species could be identified successfully by the BLAST1 method in conjunction with the nearest distance method. And, the species resolution rate of the TaxonGap method exceeded 93%. The results provide support for the use of the psbA-trnH plastid region as a sensitive marker to the authentication of Fabaceae medicinal plants.

  14. Developmental and morphological studies of the suspensor and coleorhizae in some taxa of the subfamily mimosoideae (fabaceae)

    International Nuclear Information System (INIS)

    Shi, C.Q.; Liu, M.; Zhang, X.X.; Cheng, X.Y.; Wang, C.

    2015-01-01

    The embryo development of Mimosa pudica and the seedling development of Acacia farnesiana, Albizzia julibrissin, Leucaena glauca and Mimosa pudica were studied by wax method in this paper. The results showed that M. pudica has a suspensor composed of about ten cells which degenerate and integrate into the embryo proper during the cotyledons development. The coleorhiza in M. pudica is from the residual suspensor cells and the cells produced by periclinal and anticlinal divisions of the meristematic cells in the embryo development. The coleorhiza in the four studied taxa is broken by the elongation of the primary root, withdraws and finally falls off during the seedling development. (author)

  15. A New Aggreceride analogue and a peltogynoid isolated from the stem bark of Entada abyssinica (Fabaceae).

    Science.gov (United States)

    Melong, Raduis; Kapche, Deccaux G F W; Feussia, Michel T; Laatsch, Hartmut

    2014-10-01

    A new monoglyceride, l',26'-bis-[(S)-2,3-dihydroxypropyl] hexacosanedioate (1a) and the new peltogynoid, entadanin (3), along with eight known compounds, were isolated from the stem bark of Entada abyssinica (Fabaceae). The structures of the new compounds were determined by detailed analyses of 1D and 2D NMR spectra, in combination with high-resolution mass spectrometry data, and by comparison with related data from the literature. The stereochemistry of la was derived by comparison of the optical rotation with reference data. Peltogynoids have been reported previously from other Fabaceae, however this is the first report ofa peltogynoid from the genus Entada.

  16. Ultrastructure and post-floral secretion of the pericarpial nectaries of Erythrina speciosa (Fabaceae).

    Science.gov (United States)

    Paiva, Elder Antônio Sousa

    2009-10-01

    The occurrence of nectaries in fruits is restricted to a minority of plant families and consistent reports of their occurrence are not found associated with Fabaceae, mainly showing cellular details. The present study aims to describe the anatomical organization and ultrastructure of the pericarpial nectaries (PNs) in Erythrina speciosa, a bird-pollinated species, discussing functional aspects of these unusual structures. Samples of floral buds, ovaries of flowers at anthesis and fruits at several developmental stages were fixed and processed by the usual methods for studies using light, and scanning and transmission electron microscopy. Nectar samples collected by filter paper wicks were subjected to chemical analysis using thin-layer chromatography. The PNs are distributed in isolation on the exocarp. Each PN is represented by a single hyaline trichome that consists of a basal cell at epidermal level, stalk cell(s) and a small secretory multicellular head. The apical stalk cell shows inner periclinal and anticlinal walls impregnated by lipids and lignin and has dense cytoplasm with a prevalence of mitochondria and endoplasmic reticulum. The secretory cells show voluminous nuclei and dense cytoplasm, which predominantly has dictyosomes, rough endoplasmic reticulum, plastids, mitochondria and free ribosomes. At the secretory stage the periplasmic space is prominent and contains secretion residues. Tests for sugar indicate the presence of non-reducing sugars in the secretory cells. Nectar samples from PNs contained sucrose, glucose and fructose. The secretory stage of these PNs extends until fruit maturation and evidence suggests that the energetic source of nectar production is based on pericarp photosynthesis. Patrolling ants were seen foraging on fruits during all stages of fruit development, which suggests that the PNs mediate a symbiotic relationship between ants and plant, similar to the common role of many extrafloral nectaries.

  17. Breeding biology of the threadstalk milkvetch, Astragalus filipes (Fabaceae), with a review of the genus

    Science.gov (United States)

    Astragalus L. (Fabaceae) is an enormous and diverse plant genus with a cosmopolitan distribution, but relatively few breeding biologies are known for its member species. Threadstalk (or basalt) milkvetch, Astragalus filipes Torrey ex. A. Gray, is common and widespread throughout the US Intermountai...

  18. Bioacoustics of Acanthoscelides obtectus (Coleoptera: Chrysomelidae: Bruchinae) on Phaseolus vulgaris (Fabaceae)

    Science.gov (United States)

    Acanthoscelides obtectus (Say) (Coleoptera: Chrysomelidae), is an economically important pest of common bean Phaseolus vulgaris L. (Fabaceae) in the tropics and subtropics. It is difficult to detect the presence of A. obtectus because the larvae are cryptic and spend most of their developmental time...

  19. Breeding biology of the threadstalk milkvetch, Astragalus filipes (Fabaceae), with a review of the genus

    Science.gov (United States)

    Kristal M. Watrous; James H. Cane

    2011-01-01

    Astragalus L. (Fabaceae) is an enormous and diverse plant genus with a cosmopolitan distribution, but relatively few breeding biologies are known for its member species. Threadstalk (or basalt) milkvetch, Astragalus filipes Torrey ex. A. Gray, is common and widespread throughout the U.S. Intermountain West, including the Great Basin. It is being studied and ultimately...

  20. Rationale for using Peltophorum africanum (Fabaceae extracts in veterinary medicine

    Directory of Open Access Journals (Sweden)

    S.E. Bizimenyera

    2005-06-01

    Full Text Available Peltophorum africanum (Fabaceae is a deciduous tree widespread in southern Africa. The plant has many ethnomedical and ethnoveterinary uses. Root and bark decoctions are used to treat diarrhoea, dysentery, sore throat, wounds, back and joint pains, HIV-AIDS, venereal diseases and infertility. Pastoralists and rural farmers use the root and bark extracts to treat diarrhoea, dysentery, infertility, and to promote well-being and resistance to diseases in cattle. To evaluate these ethnobotanical leads, dried leaves, stem bark and root bark were extracted with ethanol, acetone, dichloromethane and hexane. Polyphenols in the extract were determined by the Folin-Ciocalteu method with gallic acid as standard. Qualitative antioxidant activity was screened by spraying thin layer chromatograms (TLC of the extracts with 0.2 % 1, 1-diphenyl-2-picryl hydrazyl (DPPH, and quantified with Trolox equivalent antioxidant capacity (TEAC assay. Minimum inhibitory concentration (MIC and total antibacterial activity (TAA were determined by serial microplate dilution for Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Enterococcus faecalis, with gentamicin as standard and tetrazolium violet as growth indicator. Acetone and ethanol extracted the largest quantity of material. Polyphenols concentration was 49.2% in acetone extract of the root and 3.8 % in dichloromethane extract of the leaf. Antioxidant activity of at least 5 antioxidant compounds as measured by TEAC ranged from 1.34 (ethanol extract of the root to 0.01 (hexane extract of the leaf. The total antibacterial activity (volume to which active compounds present in 1 g plant material can be diluted and still inhibit bacterial growth was 1263 mℓ/g for ethanol extract of the root against S. aureus, and 800 mℓ/g for acetone extract of the root against P. aeruginosa. There was substantial activity against both Gram-positive and Gram-negative bacteria, with MIC values of 0.08 mg/mℓ for S

  1. The Usefulness of Edible and Medicinal Fabaceae in Argentine and Chilean Patagonia: Environmental Availability and Other Sources of Supply

    OpenAIRE

    Molares, Soledad; Ladio, Ana

    2011-01-01

    Fabaceae is of great ethnobotanical importance in indigenous and urban communities throughout the world. This work presents a revision of the use of Fabaceae as a food and/or medicinal resource in Argentine-Chilean Patagonia. It is based on a bibliographical analysis of 27 ethnobotanical sources and catalogues of regional flora. Approximately 234 wild species grow in Patagonia, mainly (60%) in arid environments, whilst the remainder belong to Sub-Antarctic forest. It was found that 12.8% (30 ...

  2. Dormancy-breaking requirements of Sophora tomentosa and Erythrina speciosa (Fabaceae seeds

    Directory of Open Access Journals (Sweden)

    Carolina Maria Luzia Delgado

    2015-03-01

    Full Text Available The physical dormancy of seeds has been poorly studied in species from tropical forests, such as the Atlantic Forest. This study aimed to examine the effect of moderate alternating temperatures on breaking the physical dormancy of seeds, the morphoanatomy and histochemistry of seed coats, and to locate the structure/region responsible for water entrance into the seed, after breaking the physical dormancy of seeds of two woody Fabaceae (subfamily Faboideae species that occur in the Brazilian Atlantic Forest: Sophora tomentosa and Erythrina speciosa. To assess temperature effect, seeds were incubated in several temperature values that occur in the Atlantic Forest. For morphological and histochemical studies, sections of fixed seeds were subjected to different reagents, and were observed using light or epifluorescence microscopy, to analyze the anatomy and histochemistry of the seed coat. Treated and non-treated seeds were also analyzed using a scanning electron microscope (SEM to observe the morphology of the seed coat. To localize the specific site of water entrance, the seeds were blocked with glue in different regions and also immersed in ink. In the present work a maximum temperature fluctuation of 15ºC was applied during a period of 20 days and these conditions did not increase the germination of S. tomentosa or E. speciosa. These results may indicate that these seeds require larger fluctuation of temperature than the applied or/and longer period of exposition to the temperature fluctuation. Blocking experiments water inlet combined with SEM analysis of the structures of seed coat for both species showed that besides the lens, the hilum and micropyle are involved in water absorption in seeds scarified with hot water. In seeds of E. speciosa the immersion of scarified seeds into an aniline aqueous solution showed that the solution first entered the seed through the hilum. Both species showed seed morphological and anatomical features for seed

  3. The complete chloroplast genomes of two Wisteria species, W. floribunda and W. sinensis (Fabaceae).

    Science.gov (United States)

    Kim, Na-Rae; Kim, Kyunghee; Lee, Sang-Choon; Lee, Jung-Hoon; Cho, Seong-Hyun; Yu, Yeisoo; Kim, Young-Dong; Yang, Tae-Jin

    2016-11-01

    Wisteria floribunda and Wisteria sinensis are ornamental woody vines in the Fabaceae. The complete chloroplast genome sequences of the two species were generated by de novo assembly using whole genome next generation sequences. The chloroplast genomes of W. floribunda and W. sinensis were 130 960 bp and 130 561 bp long, respectively, and showed inverted repeat (IR)-lacking structures as those reported in IRLC in the Fabaceae. The chloroplast genomes of both species contained same number of protein-coding sequences (77), tRNA genes (30), and rRNA genes (4). The phylogenetic analysis with the reported chloroplast genomes confirmed close taxonomical relationship of W. floribunda and W. sinensis.

  4. Chemical constituents from Astragalus annularis Forssk. and A. trimestris L., Fabaceae

    Directory of Open Access Journals (Sweden)

    Amr M. El-Hawiet

    2010-11-01

    Full Text Available The phytochemical investigation of the aerial parts of Astragalus annularis Forssk. and A. trimestris L., Fabaceae, growing in Egypt, resulted in the isolation of eight compounds, for the first time from these two species. These compounds were identified by chemical methods, NMR spectroscopy, UV spectroscopy as well as MS analysis. The antimicrobial activity of the isolated compounds were tested against Staphylococcus aureus, Esherichia coli and Candida albicans.

  5. The genus Machaerium (Fabaceae): taxonomy, phytochemistry, traditional uses and biological activities.

    Science.gov (United States)

    Amen, Yhiya M; Marzouk, Amani M; Zaghloul, Mona G; Afifi, Mohamed S

    2015-01-01

    Machaerium, in the family Fabaceae, predominantly is a genus of a Neotropical distribution of trees, shrubs, and lianas occurring from southern Mexico to Brazil and northern Argentina and as far as South America. Several Machaerium species are widely used in traditional medicine and are considered to have multiple medicinal properties. This review aims to provide up-to-date and comprehensive information on the taxonomy, phytochemistry, traditional uses and biological activities of plants in the genus Machaerium.

  6. Neolasioptera pantaneira, a new species of Cecidomyiidae (Diptera) associated with Aeschynomene denticulata (Fabaceae) from Brazil.

    Science.gov (United States)

    Maia, V C; Catian, G; Leme, F M

    2017-03-01

    A new species of gall midge that induces stem galls on Aeschynomene denticulata (Fabaceae) is described based on material collected in Pantanal (Mato Grosso do Sul, Brazil). This species is unique among the Brazilian congeners in having spatula with three convex teeth, cruciate, with defined anterolateral extensions, four lateral papillae on each side of the spatula, and three pairs of terminal papillae (larva), four-segmented palpi (adult), 17 flagellomeres (female), ovipositor about 11 times length of seventh tergite.

  7. Chloroplast and mitochondrial microsatellites for Millettia pinnata (Fabaceae) and cross-amplification in related species 1

    OpenAIRE

    Wang, Yanling; Xie, Hongxian; Yang, Yi; Huang, Yelin; Wang, Jianwu; Tan, Fengxiao

    2017-01-01

    Premise of the study: Chloroplast and mitochondrial microsatellites were identified to study the population genetics of Millettia pinnata (Fabaceae). Methods and Results: Based on publicly available plastid genome sequence data of M. pinnata, 42 primer pairs were developed, of which 17 displayed polymorphisms across 89 individuals from four populations. For chloroplast loci, two to six alleles were recovered and the unbiased haploid diversity per locus ranged from 0.391 to 0.857. For mitochon...

  8. Nectar robbing in Collaea cipoensis (Fabaceae), an endemic shrub of the Brazilian rupestrian grasslands

    OpenAIRE

    Gelvez-Zúñiga, Irene; Aguirre, Armando; Martén-Rodríguez, Silvana; Matos-Gomes, Vanessa; Barbosa, Arleu; Bordignon, Leandra; Rocha, Rosana; Fernandes, Geraldo W.

    2016-01-01

    Abstract: Nectar robbery is common in flowering plants with tubular corollas and can affect plant reproductive success. Our study characterized the interaction between potential pollinators and nectar robbers, and assessed the effects on flower abortion in a population of the restricted endemic Collaea cipoensis (Fabaceae) at Serra do Cipó, Brazil. We conducted observations of floral visitors to identify potential pollinators from nectar robbers and described visitor behavior. We also analyze...

  9. A review on phytochemical, ethnomedical and pharmacological studies on genus Sophora, Fabaceae

    Directory of Open Access Journals (Sweden)

    Panthati Murali Krishna

    2012-10-01

    Full Text Available Sophora is a genus of the Fabaceae family, contains about 52 species, nineteen varieties, and seven forms that are widely distributed in Asia, Oceanica, and the Pacific islands, in the family Fabaceae of herbaceous (Sophora flavescens Aiton to trees (Sophora japonica L.. More than fifteen species in this genus have a long history of use in traditional Chinese medicines. In the last decades the use of this genus in traditional Chinese drugs has led to rapid increase in the information available on active components and reported to posses various pharmacological/therapeutic properties. The paper reviews the ethnopharmacology, the biological activities and the correlated chemical compounds of genus Sophora, Fabaceae. More than 300 compounds has been isolated, among them major are quinolizidine alkaloids particularly matrine and oxymatrine and flavonoids particularly prenylated and isoprenylated flavonoids. Modern pharmacological studies and clinical studies demonstrated that these chemical constituens possess wide reaching pharmacological actions like anti oxidant, anticancer, anti-asthamatic, anti-neoplastic, antimicrobial, antiviral, antidote, anti pyretic, cardiotonic, antinflammatory, diuretic and in the treatment of skin diseases like eczema, colitis and psoriasis.

  10. Assessing universality of DNA barcoding in geographically isolated selected desert medicinal species of Fabaceae and Poaceae

    Science.gov (United States)

    Hussain, Fatma; Ahmed, Nisar; Ghorbani, Abdolbaset

    2018-01-01

    In pursuit of developing fast and accurate species-level molecular identification methods, we tested six DNA barcodes, namely ITS2, matK, rbcLa, ITS2+matK, ITS2+rbcLa, matK+rbcLa and ITS2+matK+rbcLa, for their capacity to identify frequently consumed but geographically isolated medicinal species of Fabaceae and Poaceae indigenous to the desert of Cholistan. Data were analysed by BLASTn sequence similarity, pairwise sequence divergence in TAXONDNA, and phylogenetic (neighbour-joining and maximum-likelihood trees) methods. Comparison of six barcode regions showed that ITS2 has the highest number of variable sites (209/360) for tested Fabaceae and (106/365) Poaceae species, the highest species-level identification (40%) in BLASTn procedure, distinct DNA barcoding gap, 100% correct species identification in BM and BCM functions of TAXONDNA, and clear cladding pattern with high nodal support in phylogenetic trees in both families. ITS2+matK+rbcLa followed ITS2 in its species-level identification capacity. The study was concluded with advocating the DNA barcoding as an effective tool for species identification and ITS2 as the best barcode region in identifying medicinal species of Fabaceae and Poaceae. Current research has practical implementation potential in the fields of pharmaco-vigilance, trade of medicinal plants and biodiversity conservation. PMID:29576968

  11. A review on phytochemical, ethnomedical and pharmacological studies on genus Sophora, Fabaceae

    Directory of Open Access Journals (Sweden)

    Panthati Murali Krishna

    2012-04-01

    Full Text Available Sophora is a genus of the Fabaceae family, contains about 52 species, nineteen varieties, and seven forms that are widely distributed in Asia, Oceanica, and the Pacific islands, in the family Fabaceae of herbaceous (Sophora flavescens Aiton to trees (Sophora japonica L.. More than fifteen species in this genus have a long history of use in traditional Chinese medicines. In the last decades the use of this genus in traditional Chinese drugs has led to rapid increase in the information available on active components and reported to posses various pharmacological/therapeutic properties. The paper reviews the ethnopharmacology, the biological activities and the correlated chemical compounds of genus Sophora, Fabaceae. More than 300 compounds has been isolated, among them major are quinolizidine alkaloids particularly matrine and oxymatrine and flavonoids particularly prenylated and isoprenylated flavonoids. Modern pharmacological studies and clinical studies demonstrated that these chemical constituens possess wide reaching pharmacological actions like anti oxidant, anticancer, anti-asthamatic, anti-neoplastic, antimicrobial, antiviral, antidote, anti pyretic, cardiotonic, antinflammatory, diuretic and in the treatment of skin diseases like eczema, colitis and psoriasis.

  12. OCORRÊNCIA DE FABACEAE DA ÁREA DE PROTEÇÃO AMBIENTAL DA FAZENDINHA, MACAPÁ, AMAPÁ, BRASIL

    Directory of Open Access Journals (Sweden)

    Patrick de Castro Cantuária

    2017-06-01

    Full Text Available A família Fabaceae é considerada, por diversos autores, como uma das três maiores famílias de plantas em número de espécies, estando distribuídas por todo o planeta. O presente trabalho tem como objetivo investigar a diversidade de espécies da família Fabaceae na Área de Proteção Ambiental (APA da Fazendinha, localizada no Estado do Amapá, Município de Macapá, em que o ecossistema predominante é a floresta de várzea. As coletas e a herborização das Fabaceae foram realizadas mediante técnicas usuais em botânica e informações ecológicas. Dessa forma, verificou-se no levantamento que a família Fabaceae, o gênero Mora Benth. com maior frequência de espécimes. Tais informações podem auxiliar tanto a elaboração do plano de manejo da unidade de conservação quanto o entendimento do seu nível de perturbação. Palavras-chave: Fabaceae, Fitossociologia, Unidade de Conservação.

  13. Seed Carotenoid and Tocochromanol Composition of Wild Fabaceae Species Is Shaped by Phylogeny and Ecological Factors

    Science.gov (United States)

    Fernández-Marín, Beatriz; Míguez, Fátima; Méndez-Fernández, Leire; Agut, Agustí; Becerril, José M.; García-Plazaola, José I.; Kranner, Ilse; Colville, Louise

    2017-01-01

    Carotenoids distribution and function in seeds have been very scarcely studied, notwithstanding their pivotal roles in plants that include photosynthesis and phytohormone synthesis, pigmentation, membrane stabilization and antioxidant activity. Their relationship with tocochromanols, whose critical role in maintaining seed viability has already been evidenced, and with chlorophylls, whose retention in mature seed is thought to have negative effects on storability, remain also unexplored. Here, we aimed at elucidating seed carotenoids relationship with tocochromanols and chlorophylls with regard to phylogenetic and ecological traits and at understanding their changes during germination. The composition and distribution of carotenoids were investigated in seeds of a wide range of wild species across the Fabaceae (the second-most economically important family after the Poaceae). Photosynthetic pigments and tocochromanols were analyzed by HPLC in mature dry seeds of 50 species representative of 5 subfamilies within the Fabaceae (including taxa that represent all continents, biomes and life forms within the family) and at key timepoints during seedling establishment in three species representative of distinct clades. Total-carotenoids content positively correlated with tocopherols in the basal subfamilies Detarioideae, Cercidoideae, and Dialioideae, and with chlorophylls in the Papilionoideae. Papilionoideae lacked tocotrienols and had the highest total-carotenoids, chlorophyll and γ-tocopherol contents. Interestingly, lutein epoxide was present in 72% of the species including several herbs from different subfamilies. Overall, species original from temperate biomes presented higher carotenoids and lower tocochromanols levels than those from tropical biomes. Also shrub species showed higher carotenoids content than herbs and trees. During germination, total content of photosynthetic pigments increased in parallel to changes in relative abundance of carotenoids

  14. Identification of medicinal plants in the family Fabaceae using a potential DNA barcode ITS2.

    Science.gov (United States)

    Gao, Ting; Yao, Hui; Song, Jingyuan; Liu, Chang; Zhu, Yingjie; Ma, Xinye; Pang, Xiaohui; Xu, Hongxi; Chen, Shilin

    2010-07-06

    To test whether the ITS2 region is an effective marker for use in authenticating of the family Fabaceae which contains many important medicinal plants. The ITS2 regions of 114 samples in Fabaceae were amplified. Sequence assembly was assembled by CodonCode Aligner V3.0. In combination with sequences from public database, the sequences were aligned by Clustal W, and genetic distances were computed using MEGA V4.0. The intra- vs. inter-specific variations were assessed by six metrics, wilcoxon two-sample tests and "barcoding gaps". Species identification was accomplished using TaxonGAP V2.4, BLAST1 and the nearest distance method. ITS2 sequences had considerable variation at the genus and species level. The intra-specific divergence ranged from 0% to 14.4%, with an average of 1.7%, and the inter-specific divergence ranged from 0% to 63.0%, with an average of 8.6%. Twenty-four species found in the Chinese Pharmacopoeia, along with another 66 species including their adulterants, were successfully identified based on ITS2 sequences. In addition, ITS2 worked well, with over 80.0% of species and 100% of genera being correctly differentiated for the 1507 sequences derived from 1126 species belonging to 196 genera. Our findings support the notion that ITS2 can be used as an efficient and powerful marker and a potential barcode to distinguish various species in Fabaceae. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

  15. Antioxidant activity of nine Fabaceae species growing in Serbia and Montenegro.

    Science.gov (United States)

    Godevac, Dejan; Zdunić, Gordana; Savikin, Katarina; Vajs, Vlatka; Menković, Nebojsa

    2008-04-01

    The aim of this study was to investigate antioxidant capacity of nine Fabaceae species collected on the mountains of Serbia and Montenegro. Antioxidant assays with various reaction mechanisms were used, including total phenolic content by Folin-Ciocalteu, DPPH radical scavenging capacity, Trolox equivalent antioxidant capacity (TEAC) values by ABTS radical cation and inhibition of liposome peroxidation. The investigated plants exhibited strong antioxidant capacity in all the tested methods, and among them, Lathyrus binatus, Trifolium pannonicum, and Anthyllis aurea were found to be the most active.

  16. The rediscovery of Astragalus autranii (Fabaceae) on Mt Tomor, south central Albania

    DEFF Research Database (Denmark)

    Tan, Kit; Shuka, Lulezim; Gjeta, Ermelinda

    2015-01-01

    Astragalus autranii (Fabaceae) placed by Sytin & Podlech in a section of its own (A. sect. Baldaccia) was described from a single specimen in the Barbey-Boissier Herbarium at Geneva. Our observations show that its placement in A. sect. Hololeuce would also be appropriate. The species was first co...... by Markgraf. Information on habitat, ecology and threat status are also detailed for the first time. Mt Tomor is designated as a protected National Park; however, some of the Astragalus populations may be affected by future road construction....

  17. A new species of Astragalus (Fabaceae from west coast of Baikal Lake (Irkutsk Oblast

    Directory of Open Access Journals (Sweden)

    N. V. Stepantsova

    2015-05-01

    Full Text Available A new species, Astragalus rytyensis Stepantsova (Fabaceae, growing on the west coast of the lake Baikal, is described. Morphological differences from related taxa – A. versicolor Pall., A. austrosibiricus Schischk., and A. inopinatus Boriss., are discussed and uncertain position of the new species in the system of the genus is emphasized which is intermediate between subg. Phaca (L. Bunge sect. Hemiphaca Bunge and subg. Cercidothrix Bunge sect. Onobrychium Bunge. Ecological and phonological features of A. rytyensis are reported and chromosome numbers of the new (2n = 6x = 48 and related species are counted.

  18. SUKU FABACEAE DI KAMPUS UNIVERSITAS ISLAM NEGERI SYARIF HIDAYATULLAH, JAKARTA, BAGIAN 2: TUMBUHAN POLONG BERPERAWAKAN TERNA

    Directory of Open Access Journals (Sweden)

    Priyanti Priyanti

    2017-04-01

    Full Text Available Abstrak Suku Fabaceae adalah tetumbuhan yang memiliki buah bertipe polong. Suku tersebut selain berperawakan pohon juga berupa terna. Anggota suku Fabaceae (polong banyak ditemukan di sekitar lingkungan manusia termasuk di Kampus Universitas Islam Negeri (UIN Syarif Hidayatullah, Jakarta. Informasi mengenai keanekaragaman tumbuhan polong yang berupa terna di Kampus UIN Syarif Hidayatullah belum tersedia. Penelitian dilakukan menggunakan metode jelajah di kampus I dan II serta studi pustaka. Sebanyak 3 jenis tumbuhan polong berperawakan terna telah didapatkan di lingkungan kampus, yaitu Arachis pintoi Krapov. & W. C. Greg., Mimosa diplotricha C. Wright ex Sauvalle, dan M. pudica L. Jenis-jenis tersebut termasuk ke dalam 2 anak suku (Faboideae, Mimosoideae dan 2 puak (Aeschynomeneae, Mimoseae. Jenis-jenis tersebut tumbuh di lokasi yang berbeda-beda. Tumbuhan polong yang hanya ditemukan di Fakultas Kedokteran dan Ilmu Keshatan (FKIK adalah A. pintoi. Mimosa diplotricha ditemukan tumbuh di Pusat Laboratorium Terpadu Fakultas Sains dan Teknologi, Perpustakaan Utama, FKIK, Fakultas Sosial dan Ilmu Politik (FISIP, Wisma Syahida, Pusat Bahasa, dan Sekolah Pascasarjana, sedangkan M. pudica ditemukan Perpustakaan Utama, FISIP, dan Wisma Syahida. Kelengkapan data tentang tumbuhan polong di Kampus UIN Syarif Hidayatullah ini dapat digunakan oleh para mahasiswa untuk mempelajari keanekaragamnnya. Abstract Fabaceae is a plant with a pod-type fruit. A Habit of this family is not only trees but also herb. Fabaceae (legumes is often found on the human environment around campus included in the State Islamic University (UIN Syarif Hidayatullah, Jakarta. The Information about the legume herbs diversity on the UIN Syarif Hidayatullah yet available. The study was conducted using survey and literature methods. There were 3 species legume herbs in the campus, viz. Arachis pintoi Krapov. & W. C. Greg., Mimosa diplotricha C. Wright ex Sauvalle, and M. pudica L. All

  19. Novelties in secretory structures and anatomy of Rhynchosia (Fabaceae).

    Science.gov (United States)

    De Vargas, Wanderleia; Sartori, Ângela L B; Dias, Edna S

    2015-03-01

    A comparative anatomical study was carried out on the secretory structures of leaflets from taxa belonging to the genus Rhynchosia - taxa difficult to delimit because of uncertain interspecific relations - in order to evaluate the potential diagnostic value of these anatomical traits for taxonomic assignment. A further objective was to establish consensual denomination for these secretory structures. The new anatomical features found in these taxa were sufficiently consistent to separate the species evaluated. The presence and localization of glandular-punctate structures bulbous-based trichomes, the number of layers in the palisade parenchyma and the arrangement of vascular units distinguish the taxa investigated and these characteristics can be extended to other species of Papilionoideae. The trichomes analyzed were described and classified into five types. Depicted in diagrams, photomicrographs, and by scanning electron microscopy, and listed for the first time at the genus and species levels. The information obtained served to effectively distinguish the taxa investigated among species of Papilonoideae.

  20. Determination of a-glucosidase inhibitory activity from selected Fabaceae plants.

    Science.gov (United States)

    Dej-Adisai, Sukanya; Pitakbut, Thanet

    2015-09-01

    Nineteen plants from Fabaceae family, which were used in Thai traditional medicine for treatment of diabetes, were determined of α-glucosidase inhibitory activity via enzymatic reaction. In this reaction, α-glucosidase was used as enzyme, which, reacted with the substrate, p-nitrophenol-D-glucopyranoside (pNPG). After that the product, p-nitro phenol (pNP) will be occurred and observed the yellow colour at 405 nm. In this study, acarbose was used as positive standard which, inhibited this enzyme with IC₅₀ as 331 ± 4.73 μg/ml. Caesalpinia pulcherrima leaves showed the highest activity with IC₅₀ as 436.97 ± 9.44 μg/ml. Furthermore, Bauhinia malabarica leaves presented moderately activity with IC₅₀ as 745.08 ± 11.15 μg/ml. However, the other plants showed mild to none activity of α-glucosidase inhibition. Accordingly, this study can support anti-diabetes of these plants in traditional medicine and it will be the database of the biological activity of Fabaceae plant.

  1. The single evolutionary origin of chlorinated auxin provides a phylogenetically informative trait in the Fabaceae.

    Science.gov (United States)

    Lam, Hong Kiat; Ross, John J; McAdam, Erin L; McAdam, Scott A M

    2016-07-02

    Chlorinated auxin (4-chloroindole-3-acetic acid, 4-Cl-IAA), a highly potent plant hormone, was once thought to be restricted to species of the tribe Fabeae within the Fabaceae, until we recently detected this hormone in the seeds of Medicago, Melilotus and Trifolium species. The absence of 4-Cl-IAA in the seeds of the cultivated species Cicer aeritinum from the Cicerae tribe, immediately basal to the Fabeae and Trifolieae tribes, suggested a single evolutionary origin of 4-Cl-IAA. Here, we provide a more robust phylogenetic placement of the ability to produce chlorinated auxin by screening key species spanning this evolutionary transition. We report no detectable level of 4-Cl-IAA in Cicer echinospermum (a wild relative of C. aeritinum) and 4 species (Galega officinalis, Parochetus communis, Astragalus propinquus and A. sinicus) from tribes or clades more basal or sister to the Cicerae tribe. We did detect 4-Cl-IAA in the dry seeds of 4 species from the genus Ononis that are either basal to the genera Medicago, Melilotus and Trigonella or basal to, but still within, the Fabeae and Trifolieae (ex. Parochetus) clades. We conclude that the single evolutionary origin of this hormone in seeds can be used as a phylogenetically informative trait within the Fabaceae.

  2. Vicia vulcanorum (Fabaceae a new species from the island of Lanzarote (Canary Islands

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    Morales-Mateos, J. B.

    2012-12-01

    Full Text Available Vicia vulcanorum J. Gil & M. L. Gil (Fabaceae, a new species of subg. Cracca (Dumort. Peterm., sect. Cracca Dumort. is described and illustrated from the island of Lanzarote, Canary Islands, north-west of Africa. It is related to and compared with Vicia cirrhosa C. Sm. ex Webb & Berthel. and Vicia filicaulis Webb & Berthel., two endemic species from the western and central group of the Canary Islands, and Vicia ferreirensis Goyder, an endemic species from Porto Santo Island, Madeira Archipelago.Se describe e ilustra Vicia vulcanorum J. Gil & M. L. Gil (Fabaceae, una nueva especie y endemismo de la isla de Lanzarote, Islas Canarias, perteneciente al subg. Cracca (Dumort. Peterm., sect. Cracca Dumort. Se encuentra relacionada y es comparada con Vicia cirrhosa C. Sm. ex Webb & Berthel. y Vicia filicaulis Webb & Berthel., especies endémicas de las islas centrales y occidentales del archipiélago canario, y con Vicia ferreirensis Goyder, especie endémica de la isla de Porto Santo, en el archipiélago de Madeira.

  3. Biological activity and LC-MS/MS profiling of extracts from the Australian medicinal plant Acacia ligulata (Fabaceae)

    DEFF Research Database (Denmark)

    Knudsen, Diana Jæger; Simpson, Bradley S.; Ndi, Chi P.

    2018-01-01

    Acacia ligulata A.Cunn. ex Benth. (Fabaceae: Mimosoideae) is a native Australian plant used traditionally by Australian Aboriginal groups. This study was undertaken to investigate the bioactivity of A. ligulata extracts and to evaluate their chemical composition. Potential antibacterial, cytotoxic...

  4. Is induction ability of seed germination of Phelipanche ramosa phylogenetically structured among hosts? A case study on Fabaceae species.

    Science.gov (United States)

    Perronne, Rémi; Gibot-Leclerc, Stéphanie; Dessaint, Fabrice; Reibel, Carole; Le Corre, Valérie

    2017-12-01

    Phelipanche ramosa is a major root-holoparasitic damaging weed characterized by a broad host range, including numerous Fabaceae species. In France, the agricultural threat posed by P. ramosa has increased over two decades due to the appearance of a genetically differentiated pathovar presenting a clear host specificity for oilseed rape. The new pathovar has led to a massive expansion of P. ramosa in oilseed rape fields. The germination rate of P. ramosa seeds is currently known to vary among P. ramosa pathovars and host species. However, only a few studies have investigated whether phylogenetic relatedness among potential host species is a predictor of the ability of these species to induce the seed germination of parasitic weeds by testing for phylogenetic signal. We focused on a set of 12 Fabaceae species and we assessed the rate of induction of seed germination by these species for two pathovars based on in vitro co-cultivation experiments. All Fabaceae species tested induced the germination of P. ramosa seeds. The germination rate of P. ramosa seeds varied between Fabaceae species and tribes studied, while pathovars appeared non-influential. Considering oilseed rape as a reference species, we also highlighted a significant phylogenetic signal. Phylogenetically related species therefore showed more similar rates of induction of seed germination than species drawn at random from a phylogenetic tree. In in vitro conditions, only Lotus corniculatus induced a significantly higher germination rate than oilseed rape, and could potentially be used as a catch crop after confirmation of these results under field conditions.

  5. The position of prenylation of isoflavonoids and stilbenoids from legumes (Fabaceae) modulates the antimicrobial activity against Gram positive pathogens

    NARCIS (Netherlands)

    Araya-Cloutier, Carla; Besten, den Heidy M.W.; Aisyah, Siti; Gruppen, Harry; Vincken, Jean Paul

    2017-01-01

    The legume plant family (Fabaceae) is a potential source of antimicrobial phytochemicals. Molecular diversity in phytochemicals of legume extracts was enhanced by germination and fungal elicitation of seven legume species, as established by RP-UHPLC–UV–MS. The relationship between phytochemical

  6. Evaluation Introduction Albizia julibrissin Durazz in Kherson City

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    Boiko Tatiana

    2017-01-01

    Full Text Available The article raised questions diversification of ornamental plants for landscaping of Kherson city. We consider the effectiveness of widespread use in gardening Kherson city highly ornamental exotic species albutsiya lankaran. The rapid growth of plants, indiscriminateness to soil fertility, the ability to abundant seed and coppice restoration, resistance to the conditions of urban areas makes albutsiya promising for widespread use in gardening. In the course of the studies found that albutsiya lankaran rated as mild winter-hardy and moderately drought-resistant species, in desert climate conditions regularly damaged but recovered. Maximum decorative displays at the correct location: maximum light and moderate soil moisture. The plant shows high resistance to diseases and pests.

  7. Electronics

    Science.gov (United States)

    2001-01-01

    International Acer Incorporated, Hsin Chu, Taiwan Aerospace Industrial Development Corporation, Taichung, Taiwan American Institute of Taiwan, Taipei, Taiwan...Singapore and Malaysia .5 - 4 - The largest market for semiconductor products is the high technology consumer electronics industry that consumes up...Singapore, and Malaysia . A new semiconductor facility costs around $3 billion to build and takes about two years to become operational

  8. Seed storage protein gene promoters contain conserved DNA motifs in Brassicaceae, Fabaceae and Poaceae

    Science.gov (United States)

    Fauteux, François; Strömvik, Martina V

    2009-01-01

    Background Accurate computational identification of cis-regulatory motifs is difficult, particularly in eukaryotic promoters, which typically contain multiple short and degenerate DNA sequences bound by several interacting factors. Enrichment in combinations of rare motifs in the promoter sequence of functionally or evolutionarily related genes among several species is an indicator of conserved transcriptional regulatory mechanisms. This provides a basis for the computational identification of cis-regulatory motifs. Results We have used a discriminative seeding DNA motif discovery algorithm for an in-depth analysis of 54 seed storage protein (SSP) gene promoters from three plant families, namely Brassicaceae (mustards), Fabaceae (legumes) and Poaceae (grasses) using backgrounds based on complete sets of promoters from a representative species in each family, namely Arabidopsis (Arabidopsis thaliana (L.) Heynh.), soybean (Glycine max (L.) Merr.) and rice (Oryza sativa L.) respectively. We have identified three conserved motifs (two RY-like and one ACGT-like) in Brassicaceae and Fabaceae SSP gene promoters that are similar to experimentally characterized seed-specific cis-regulatory elements. Fabaceae SSP gene promoter sequences are also enriched in a novel, seed-specific E2Fb-like motif. Conserved motifs identified in Poaceae SSP gene promoters include a GCN4-like motif, two prolamin-box-like motifs and an Skn-1-like motif. Evidence of the presence of a variant of the TATA-box is found in the SSP gene promoters from the three plant families. Motifs discovered in SSP gene promoters were used to score whole-genome sets of promoters from Arabidopsis, soybean and rice. The highest-scoring promoters are associated with genes coding for different subunits or precursors of seed storage proteins. Conclusion Seed storage protein gene promoter motifs are conserved in diverse species, and different plant families are characterized by a distinct combination of conserved motifs

  9. Seed storage protein gene promoters contain conserved DNA motifs in Brassicaceae, Fabaceae and Poaceae

    Directory of Open Access Journals (Sweden)

    Fauteux François

    2009-10-01

    Full Text Available Abstract Background Accurate computational identification of cis-regulatory motifs is difficult, particularly in eukaryotic promoters, which typically contain multiple short and degenerate DNA sequences bound by several interacting factors. Enrichment in combinations of rare motifs in the promoter sequence of functionally or evolutionarily related genes among several species is an indicator of conserved transcriptional regulatory mechanisms. This provides a basis for the computational identification of cis-regulatory motifs. Results We have used a discriminative seeding DNA motif discovery algorithm for an in-depth analysis of 54 seed storage protein (SSP gene promoters from three plant families, namely Brassicaceae (mustards, Fabaceae (legumes and Poaceae (grasses using backgrounds based on complete sets of promoters from a representative species in each family, namely Arabidopsis (Arabidopsis thaliana (L. Heynh., soybean (Glycine max (L. Merr. and rice (Oryza sativa L. respectively. We have identified three conserved motifs (two RY-like and one ACGT-like in Brassicaceae and Fabaceae SSP gene promoters that are similar to experimentally characterized seed-specific cis-regulatory elements. Fabaceae SSP gene promoter sequences are also enriched in a novel, seed-specific E2Fb-like motif. Conserved motifs identified in Poaceae SSP gene promoters include a GCN4-like motif, two prolamin-box-like motifs and an Skn-1-like motif. Evidence of the presence of a variant of the TATA-box is found in the SSP gene promoters from the three plant families. Motifs discovered in SSP gene promoters were used to score whole-genome sets of promoters from Arabidopsis, soybean and rice. The highest-scoring promoters are associated with genes coding for different subunits or precursors of seed storage proteins. Conclusion Seed storage protein gene promoter motifs are conserved in diverse species, and different plant families are characterized by a distinct combination

  10. Tortricid moths (Lepidopotera: Tortricidae) reared from the invasive weed Parkinsonia aculeta (Fabaceae), with comments on their host specificity, biology, and geographic distribution

    Science.gov (United States)

    During efforts to identify native herbivores of Parkinsonia aculeata L. (Fabaceae: Caesalpiniodeae) as potential biological control agents against this invasive weed in Australia, seven species of Tortricidae were reared in Mexico, Guatemala, Nicaragua, and Venezuela: Amorbia concavana (Zeller), Pla...

  11. Seed storage-mediated dormancy alleviation in Fabaceae from campo rupestre

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    Naïla Nativel

    2015-09-01

    Full Text Available ABSTRACTWe studied the effects of seed storage on germination and dormancy alleviation in three species of Fabaceae endemic to campo rupestrein southeastern Brazil. Fresh seeds of Collaea cipoensis, Mimosa maguirei and Mimosa foliolosawere set to germinate and germination of seeds after four, five and 13 years of storage was tested. Seed viability was maintained for all species after the full storage period. Seed storage significantly increased germination percentage and decreased germination time for C. cipoensisand M. foliolosa, suggesting the alleviation of physical dormancy with storage. However, we did not find evidence of dormancy alleviation in M. maguirei since stored seeds showed a decrease in germination in comparison to that of fresh seeds. Our data indicate species-specific storage-mediated dormancy alleviation, which will have important implications for restoration of campo rupestre.

  12. Molecular systematics of Indian Alysicarpus (Fabaceae) based on analyses of nuclear ribosomal DNA sequences.

    Science.gov (United States)

    Gholami, Akram; Subramaniam, Shweta; Geeta, R; Pandey, Arun K

    2017-06-01

    Alysicarpus Necker ex Desvaux (Fabaceae, Desmodieae) consists of ~30 species that are distributed in tropical and subtropical regions of theworld. In India, the genus is represented by ca. 18 species, ofwhich seven are endemic. Sequences of the nuclear Internal transcribed spacer from38 accessions representing 16 Indian specieswere subjected to phylogenetic analyses. The ITS sequence data strongly support the monophyly of the genus Alysicarpus. Analyses revealed four major well-supported clades within Alysicarpus. Ancestral state reconstructions were done for two morphological characters, namely calyx length in relation to pod (macrocalyx and microcalyx) and pod surface ornamentation (transversely rugose and nonrugose). The present study is the first report on molecular systematics of Indian Alysicarpus.

  13. Evidence That Chlorinated Auxin Is Restricted to the Fabaceae But Not to the Fabeae1[OPEN

    Science.gov (United States)

    McAdam, Scott A.M.; McAdam, Erin L.

    2015-01-01

    Auxin is a pivotal plant hormone, usually occurring in the form of indole-3-acetic acid (IAA). However, in maturing pea (Pisum sativum) seeds, the level of the chlorinated auxin, 4-chloroindole-3-acetic acid (4-Cl-IAA), greatly exceeds that of IAA. A key issue is how plants produce halogenated compounds such as 4-Cl-IAA. To better understand this topic, we investigated the distribution of the chlorinated auxin. We show for the first time, to our knowledge, that 4-Cl-IAA is found in the seeds of Medicago truncatula, Melilotus indicus, and three species of Trifolium. Furthermore, we found no evidence that Pinus spp. synthesize 4-Cl-IAA in seeds, contrary to a previous report. The evidence indicates a single evolutionary origin of 4-Cl-IAA synthesis in the Fabaceae, which may provide an ideal model system to further investigate the action and activity of halogenating enzymes in plants. PMID:25971549

  14. Chloroplast and mitochondrial microsatellites for Millettia pinnata (Fabaceae) and cross-amplification in related species.

    Science.gov (United States)

    Wang, Yanling; Xie, Hongxian; Yang, Yi; Huang, Yelin; Wang, Jianwu; Tan, Fengxiao

    2017-05-01

    Chloroplast and mitochondrial microsatellites were identified to study the population genetics of Millettia pinnata (Fabaceae). Based on publicly available plastid genome sequence data of M. pinnata , 42 primer pairs were developed, of which 17 displayed polymorphisms across 89 individuals from four populations. For chloroplast loci, two to six alleles were recovered and the unbiased haploid diversity per locus ranged from 0.391 to 0.857. For mitochondrial loci, two to four alleles were recovered and the unbiased haploid diversity ranged from 0.264 to 0.740. Sixteen of the 17 screened markers could be successfully amplified in the related species M. pulchra . The 17 microsatellite markers developed here exhibited variation in M. pinnata and 16 presented transferability in the related species M. pulchra , suggesting that these markers will be valuable for genetic studies across M. pinnata and its related species.

  15. Chloroplast and mitochondrial microsatellites for Millettia pinnata (Fabaceae) and cross-amplification in related species1

    Science.gov (United States)

    Wang, Yanling; Xie, Hongxian; Yang, Yi; Huang, Yelin; Wang, Jianwu; Tan, Fengxiao

    2017-01-01

    Premise of the study: Chloroplast and mitochondrial microsatellites were identified to study the population genetics of Millettia pinnata (Fabaceae). Methods and Results: Based on publicly available plastid genome sequence data of M. pinnata, 42 primer pairs were developed, of which 17 displayed polymorphisms across 89 individuals from four populations. For chloroplast loci, two to six alleles were recovered and the unbiased haploid diversity per locus ranged from 0.391 to 0.857. For mitochondrial loci, two to four alleles were recovered and the unbiased haploid diversity ranged from 0.264 to 0.740. Sixteen of the 17 screened markers could be successfully amplified in the related species M. pulchra. Conclusions: The 17 microsatellite markers developed here exhibited variation in M. pinnata and 16 presented transferability in the related species M. pulchra, suggesting that these markers will be valuable for genetic studies across M. pinnata and its related species. PMID:28529836

  16. Cytisus scoparius (Fam. Fabaceae in southern Brazil - first step of an invasion process?

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    Rodrigo León Cordero

    2016-03-01

    Full Text Available The occurrence of Scotch broom Cytisus scoparius (L. Link (Fabaceae, is reported for the first time in Brazil. The species has been registered in the species-rich Campos Sulinos grasslands, in the Campos de Cima da Serra, and in the Serra do Sudeste. Naturalizing populations were frequently formed in natural habitats near to human settlements, where prevailing land uses and disturbances facilitate dispersal and establishment. The plant is an invasive species that has globally caused significant damage to biodiversity and economic losses. In Brazil, the species has a strong potential for spreading into a wide range of ecosystems. The Atlantic Forest biome and part of the Pampa biome, together known as the Campos Sulinos, represent optimal areas for the species. Features of the observed populations and recommendations for management are presented.

  17. The genus Desmodium (Fabaceae)-traditional uses in Chinese medicine, phytochemistry and pharmacology.

    Science.gov (United States)

    Ma, Xueqin; Zheng, Chengjian; Hu, Changling; Rahman, Khalid; Qin, Luping

    2011-11-18

    Plants of the genus Desmodium (Fabaceae), such as Desmodium styracifolium (Osbeck) Merr. and Desmodium gyrans (L. f.) DC., have a long history of medical use in Traditional Chinese Medicine to treat various ailments including rheumatism, pyrexia, dysentery, wounds, cough, malaria, hepatitis, hemoptysis, etc. In the theory of Traditional Chinese Medicine, most species have the effect of relieving internal heat or fever, neutralizing toxins, inhibiting pain, invigorating blood circulation, suppressing cough and alleviating dyspnea. A bibliographic investigation was accomplished by analyzing secondary sources including Chinese Herbal Classics, and worldwide accepted scientific databases (Pubmed, Scopus and Web of Science, SciFinder) were scrutinized for the available information on the ethnopharmacological uses in Chinese medicine, phytochemistry, pharmacology and toxicology of Desmodium species. The genus Desmodium is a large member of the Papilionaceae (Fabaceae) family. It contains about 350 plant species used for both feeding stuffs and herbal medicines, of which only about 30 species have been phytochemically or pharmacologically investigated. Desmodium plant extracts, as well as the active principles, have been experimentally studied for their anti-inflammatory, cytotoxic, antidiabetic, antinephrolithic, antibacterial, and nootropic activities in vitro or in vivo. And so far, a total of 212 compounds have been isolated from 15 Desmodium species and characterized mainly as flavonoids and alkaloids, followed by terpenoids, steroids, phenols, phenylpropanoids, glycosides and a number of volatile oils. The remaining unrevealed species are recorded chiefly in Asia and Africa being used in empirical treatment for various diseases. Desmodium species have long been used in TCM to treat various ailments. Available scientific references revealed that the traditional medical uses of some important Desmodium species in TCM have been evaluated by modern pharmacological

  18. No evidence for Fabaceae Gametophytic self-incompatibility being determined by Rosaceae, Solanaceae, and Plantaginaceae S-RNase lineage genes.

    Science.gov (United States)

    Aguiar, Bruno; Vieira, Jorge; Cunha, Ana E; Vieira, Cristina P

    2015-06-02

    Fabaceae species are important in agronomy and livestock nourishment. They have a long breeding history, and most cultivars have lost self-incompatibility (SI), a genetic barrier to self-fertilization. Nevertheless, to improve legume crop breeding, crosses with wild SI relatives of the cultivated varieties are often performed. Therefore, it is fundamental to characterize Fabaceae SI system(s). We address the hypothesis of Fabaceae gametophytic (G)SI being RNase based, by recruiting the same S-RNase lineage gene of Rosaceae, Solanaceae or Plantaginaceae SI species. We first identify SSK1 like genes (described only in species having RNase based GSI), in the Trifolium pratense, Medicago truncatula, Cicer arietinum, Glycine max, and Lupinus angustifolius genomes. Then, we characterize the S-lineage T2-RNase genes in these genomes. In T. pratense, M. truncatula, and C. arietinum we identify S-RNase lineage genes that in phylogenetic analyses cluster with Pyrinae S-RNases. In M. truncatula and C. arietinum genomes, where large scaffolds are available, these sequences are surrounded by F-box genes that in phylogenetic analyses also cluster with S-pollen genes. In T. pratense the S-RNase lineage genes show, however, expression in tissues not involved in GSI. Moreover, levels of diversity are lower than those observed for other S-RNase genes. The M. truncatula and C. arietinum S-RNase and S-pollen like genes phylogenetically related to Pyrinae S-genes, are also expressed in tissues other than those involved in GSI. To address if other T2-RNases could be determining Fabaceae GSI, here we obtained a style with stigma transcriptome of Cytisus striatus, a species that shows significant difference on the percentage of pollen growth in self and cross-pollinations. Expression and polymorphism analyses of the C. striatus S-RNase like genes revealed that none of these genes, is the S-pistil gene. We find no evidence for Fabaceae GSI being determined by Rosaceae, Solanaceae, and

  19. Anti-inflammatory activity of Adenanthera pavonina L., Fabaceae, in experimental animals Atividade anti-inflamatória de Adenanthera pavonina L., Fabaceae, em animais experimentais

    Directory of Open Access Journals (Sweden)

    Arzumand Ara

    2010-12-01

    Full Text Available Adenanthera pavonina L, Fabaceae alt. Leguminosae, Bengali name 'rakta kombol', is an Indian medicinal plant. It is endemic to Southern China and India, and widely naturalized in Malaysia, Western and Eastern Africa as well as in most islands of both the Pacific and Caribbean regions. This plant has been used in traditional medicine for the treatment of asthma, boil, diarrhoea, gout, inflammations, rheumatism, tumour and ulcers, and as a tonic. The dried and ground bark of A. pavonina L. was extracted, successively, with petroleum ether (PE, dichloromethane (DCM, ethyl acetate (EtOAc and methanol (MeOH, and the resulting extracts were assessed in vivo for anti-inflammatory activity on carrageenan-induced rat hind paw oedema as a model of inflammation. The extracts were administered orally at the doses of 200 and 400 mg/kg body weight, and statistically significant (pAdenanthera pavonina L, Fabaceae, conhecida na região de Bengala por "rakta kombol", é uma planta medicinal endêmica do sul da China e da Índia e amplamente difundida na Malásia, África Ocidental e Oriental, bem como na maioria das ilhas de ambas as regiões do Pacífico e Caribe. Esta planta tem sido utilizada na medicina tradicional para o tratamento da asma, febre, diarréia, gota, inflamações, reumatismo tumor, úlceras, e como tônico. Cascas secas e moídas de A. pavonina foi submetida a extração sucessiva com éter de petróleo (PE, diclorometano (DCM, acetato de etila (AcOEt e metanol (MeOH, e os extratos foram avaliados in vivo para atividade anti-inflamatória induzida por carragenina tendo como ensaio modelo de inflamação edema de pata em ratos.. Os extratos foram administrados por via oral em doses de 200 e 400 mg/kg de peso corporal, e foram observadas efeitos anti-inflamatórios de maneira dose-dependente, estatisticamente significativos (p<0,001. O extrato metanólico (400 mg/kg apresentou 37,10% (p<0,01 de inibição da inflamação na primeira hora do

  20. Review of the Eriococcidae (Hemiptera: Coccomorpha) infesting Fabaceae in Argentina, with descriptions of three new species of Acanthococcus Signoret.

    Science.gov (United States)

    González, Patricia; Claps, Lucía E; Juárez, Andrea; Moreno, Diego

    2017-02-15

    Three new species of Eriococcidae from Argentina, namely Acanthococcus haywardi Juárez & González sp. nov., A. punctatae Juárez & González sp. nov. and A. riojensis Juárez & González sp. nov., are described and illustrated, bringing the total number of eriococcid species now known from Argentina to 12, of which six belong to Acanthococcus Signoret and six to Hempelicoccus Kozár. They are found on 11 species of Fabaceae (subfamilies Mimosoideae and Caesalpinioidae), are widely distributed and are all restricted to the Neotropical region and the South American Transitional Zone. A key to the 12 Eriococcidae species now known on Fabaceae in Argentina is included.

  1. New species of Lopesia Rübsaamen (Diptera: Cecidomyiidae associated with Andira humilis Mart. ex Benth. (Fabaceae

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    Carolina de Almeida Garcia

    2017-07-01

    Full Text Available A new species of Lopesia Rübsaamen, 1908 induces leaf galls on Andira humilis (Fabaceae in the Cerrado biome (Brazilian savanna of Bahia, Mato Grosso and São Paulo states, Brazil. Larva, pupa, female, and male of this new species of gall midge are described and illustrated in this paper. Keywords: Cerrado, Gall maker, Insect–plant interaction, Neotropical region, Taxonomy

  2. The Usefulness of Edible and Medicinal Fabaceae in Argentine and Chilean Patagonia: Environmental Availability and Other Sources of Supply

    Directory of Open Access Journals (Sweden)

    Soledad Molares

    2012-01-01

    Full Text Available Fabaceae is of great ethnobotanical importance in indigenous and urban communities throughout the world. This work presents a revision of the use of Fabaceae as a food and/or medicinal resource in Argentine-Chilean Patagonia. It is based on a bibliographical analysis of 27 ethnobotanical sources and catalogues of regional flora. Approximately 234 wild species grow in Patagonia, mainly (60% in arid environments, whilst the remainder belong to Sub-Antarctic forest. It was found that 12.8% (30 species, mainly woody, conspicuous plants, are collected for food or medicines. Most of the species used grow in arid environments. Cultivation and purchase/barter enrich the Fabaceae offer, bringing it up to a total of 63 species. The richness of native and exotic species, and the existence of multiple strategies for obtaining these plants, indicates hybridization of knowledge and practices. Only 22% of the total species used are mentioned in bothcontexts of food and medicine, reflecting low-use complementation. This study suggests a significant ecological appearance and a high level of availability in shops and exchange networks in Patagonia, highlighting the need to consider the full set of environmental and socioeconomic factors in research related to the use and cultural importance of plants in regional contexts.

  3. The Usefulness of Edible and Medicinal Fabaceae in Argentine and Chilean Patagonia: Environmental Availability and Other Sources of Supply

    Science.gov (United States)

    Molares, Soledad; Ladio, Ana

    2012-01-01

    Fabaceae is of great ethnobotanical importance in indigenous and urban communities throughout the world. This work presents a revision of the use of Fabaceae as a food and/or medicinal resource in Argentine-Chilean Patagonia. It is based on a bibliographical analysis of 27 ethnobotanical sources and catalogues of regional flora. Approximately 234 wild species grow in Patagonia, mainly (60%) in arid environments, whilst the remainder belong to Sub-Antarctic forest. It was found that 12.8% (30 species), mainly woody, conspicuous plants, are collected for food or medicines. Most of the species used grow in arid environments. Cultivation and purchase/barter enrich the Fabaceae offer, bringing it up to a total of 63 species. The richness of native and exotic species, and the existence of multiple strategies for obtaining these plants, indicates hybridization of knowledge and practices. Only 22% of the total species used are mentioned in bothcontexts of food and medicine, reflecting low-use complementation. This study suggests a significant ecological appearance and a high level of availability in shops and exchange networks in Patagonia, highlighting the need to consider the full set of environmental and socioeconomic factors in research related to the use and cultural importance of plants in regional contexts. PMID:22194774

  4. Evaluation of the immunotoxicological effects of Dimorphandra mollis Benth., Fabaceae, in rats

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    Cássia A. O. Feres

    Full Text Available Dimorphandra mollis Benth., Fabaceae, also known as "faveira" or "fava-d'anta", is a plant common to the central woodsy meadow region of Brazil. It is well known for its antioxidant, antiplatelet and, principally, vasoprotective properties. Its principal component is rutin. The objective of this study is the evaluation of the safety of the use of the dried D. mollis extract in rodents. The rutin content of the standardized extract was 76.0±3%. With respect to the biochemical and hematological parameters evaluated, no alterations in the groups of rats that received 1000 and 2000 mg/kg doses of D. mollis were observed, but an increase in eosinophiles occurred. Hyperactivity of the white splenic pulp was detected in the group that received the 2000 mg/kg dose of D. mollis. In the evaluation of the lymphproliferative response with 1000 and 2000 mg/kg, no alterations were observed, and a decrease in IgG was only observed in the studies with a 2000 mg/kg dose. The results obtained with rodents suggest that no toxicity exists with the administration of dried D. mollis extract in a 1000 mg/kg dose.

  5. Evidence That Chlorinated Auxin Is Restricted to the Fabaceae But Not to the Fabeae.

    Science.gov (United States)

    Lam, Hong Kiat; McAdam, Scott A M; McAdam, Erin L; Ross, John J

    2015-07-01

    Auxin is a pivotal plant hormone, usually occurring in the form of indole-3-acetic acid (IAA). However, in maturing pea (Pisum sativum) seeds, the level of the chlorinated auxin, 4-chloroindole-3-acetic acid (4-Cl-IAA), greatly exceeds that of IAA. A key issue is how plants produce halogenated compounds such as 4-Cl-IAA. To better understand this topic, we investigated the distribution of the chlorinated auxin. We show for the first time, to our knowledge, that 4-Cl-IAA is found in the seeds of Medicago truncatula, Melilotus indicus, and three species of Trifolium. Furthermore, we found no evidence that Pinus spp. synthesize 4-Cl-IAA in seeds, contrary to a previous report. The evidence indicates a single evolutionary origin of 4-Cl-IAA synthesis in the Fabaceae, which may provide an ideal model system to further investigate the action and activity of halogenating enzymes in plants. © 2015 American Society of Plant Biologists. All Rights Reserved.

  6. Morphofunctional Traits and Pollination Mechanisms of Coronilla emerus L. Flowers (Fabaceae)

    Science.gov (United States)

    Aronne, Giovanna; Giovanetti, Manuela; De Micco, Veronica

    2012-01-01

    It is accepted that the papilionaceous corolla of the Fabaceae evolved under the selective pressure of bee pollinators. Morphology and function of different parts of Coronilla emerus L. flowers were related to their role in the pollination mechanism. The corolla has a vexillum with red nectar lines, a keel hiding stamens and pistil, and two wing petals fasten to the keel with two notched folds. Pollinators land on the complex of keel and wings, trigger the protrusion of pollen and finally of the stigma from the keel tip. Data on pollen viability and stigma receptivity prove that flowers are proterandrous. The results of hand-pollination experiments confirmed that insects are fundamental to set seed. Interaction with pollinators allows not only the transport of pollen but also the rupture of the stigmatic cuticle, necessary to achieve both allogamy and autogamy. Field observations showed that Hymenoptera, Lepidoptera, and Diptera visited the flowers. Only some of the Hymenoptera landed on the flowers from the front and elicited pollination mechanisms. Most of the insects sucked the nectar from the back without any pollen transfer. Finally, morphological and functional characteristics of C. emerus flowers are discussed in terms of floral larceny and reduction in pollination efficiency. PMID:22666114

  7. Anticonvulsant effect of the ethanol extract of Caesalpiniapulcherrima (L. Sw., Fabaceae, leaves

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    Dinesh Kumar

    2010-08-01

    Full Text Available In this study, ethanol extract of Caesalpinia pulcherrima (L. Sw., Fabaceae, leaves (CPEE was investigated for anticonvulsant effect against maximal electroshock (MES and pentylenetetrazole (PTZ induced seizures in rats and mice at dose levels 200 and 400 mg/kg, i.p. respectively. Diazepam (3 mg/kg, i.p. was used as a standard anticonvulsant drug for comparison. CPEE was found to be safe up to the dose of 4000 mg/kg in mice, when administered intraperitoneally. The extract at 400 mg/kg dose produced significant (p<0.01 anticonvulsant effect w.r.t. control against PTZ-induced clonic seizures. In MES-induced seizure model, there were no significant alterations in the onset as well as duration of hind limb extension seizures as compared to control at a dose of 200 mg/kg when administered intraperitoneally. However, the extract (CPEE, 400 mg/kg i.p. significantly (p<0.01 delayed the onset as well as decreased the duration of hind limb extension seizures (HLES as compared to control. However, the extract, CPEE, percentage protection of the animals was increased at higher dose (200 mg/kg in both the models. The results of the study suggest that ethanol extract of Caesalpinia pulcherrima (L. Sw. leaves possess anticonvulsant effect.

  8. Molecular Phylogeny of Gueldenstaedtia and Tibetia (Fabaceae) and Their Biogeographic Differentiation within Eastern Asia.

    Science.gov (United States)

    Xie, Yan-Ping; Meng, Ying; Sun, Hang; Nie, Ze-Long

    2016-01-01

    Tibetia and Gueldenstaedtia are two morphologically similar and small genera in Fabaceae, with distributions largely corresponding to the Sino-Himalayan and Sino-Japanese subkingdoms in eastern Asia, respectively. These two genera have confusing relationships based on morphology; therefore, we aimed to provide a clear understanding of their phylogenetic and biogeographic evolution within eastern Asia. In our investigations we included 88 samples representing five Gueldenstaedtia species, five Tibetia species, and outgroup species were sequenced using five markers (nuclear: ITS; chloroplast: matK, trnL-F, psbA-trnH and rbcL). Our phylogenetic results support (1) the monophyly of Tibetia and of Gueldenstaedtia, respectively; and (2) that Tibetia and Gueldenstaedtia are sister genera. Additionally, our data identified that Tibetia species had much higher sequence variation than Gueldenstaedtia species. Our results suggest that the two genera were separated from each other about 17.23 million years ago, which is congruent with the Himalayan orogeny and the uplift of the Tibetan Plateau in the mid Miocene. The divergence of Tibetia and Gueldenstaedtia is strongly supported by the separation of the Sino-Himalayan and Sino-Japanese region within eastern Asia. In addition, the habitat heterogeneity may accelerate the molecular divergence of Tibetia in the Sino-Himalayan region.

  9. Enantiostyly in Chamaecrista ramosa (Fabaceae-Caesalpinioideae): floral morphology, pollen transfer dynamics and breeding system.

    Science.gov (United States)

    Almeida, N M de; Castro, C C de; Leite, A V de Lima; Novo, R R; Machado, I C

    2013-03-01

    Enantiostyly is a form of reciprocal herkogamy, in which floral morphs present reciprocal differences in the position of sexual elements, and occurs in monomorphic and dimorphic forms. This polymorphism maximises cross-pollination and reduces self-pollination, being very common within the subtribe Cassiinae (Fabaceae). Nevertheless, few studies have investigated the functionality of enantiostyly, particularly in this plant group. The present study aimed to investigate enantiostyly and its functionality in Chamaecrista ramosa, a monomorphic enantiostylous shrub, in an area of coastal vegetation in northeast Brazil. Pollen deposition and capture on the body of floral visitors, the relationship of these data with floral biology and breeding system, and morph ratio were evaluated. Pollen deposition and capture occurred in specific sites of the floral visitor body, showing the functionality of enantiostyly. The floral architecture, associated with the floral visitor behaviour, resulted in indirect pollen deposition on the floral visitor body. This occurred through a loop made by the pollen upon the inner petal surface, similar that generally reported for other Cassiinae. Chamaecrista ramosa is self-compatible, although no fruit set was observed through spontaneous self-pollination. The occurrence and number of floral morphs was similar within clumps. Enantiostyly seems to be advantageous for this species, as it results in efficient pollen capture and deposition, reduces the chances of autogamy and maximises intermorph pollen flow. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  10. Potent microbial and tyrosinase inhibitors from stem bark of Bauhinia rufescens (Fabaceae).

    Science.gov (United States)

    Muhammad, Aminu; Sirat, Hasnah Mohd

    2013-10-01

    The stem bark extracts of Bauhinia rufescens Lam. (Fabaceae) yielded 6-methoxy-7-methyl-8-hydroxydibenz[b,f]oxepin, alpha-amyrin acetate, beta-sitosterol 3-O-beta-D-xylopyranoside, 4-(2'-Hydroxyphenethyl)-5-methoxy-2-methylphenol, menisdaurin and sequoyitol. Their structures were determined using spectroscopic methods and comparisons with the literature data. For the antimicrobial assay Gram-positive and Gram-negative bacterial and fungal strains were tested, while the tyrosinase inhibition assay utilized L-DOPA as a substrate for the tyrosinase enzyme. 6-Methoxy-7-methyl-8-hydroxydibenz[b,f]oxepin, a-amyrin acetate, beta-sitosterol 3-O-D-xylopyranoside, menisdaurin and sequoyitol showed weak to moderate activities with minimum inhibition concentration (MIC) values in the range of 112.5-900 microg/mL against all bacterial strains, while the MIC values for the fungal strains were in the range of 28.1-450 microg/mL. In the tyrosinase inhibition assay, a-amyrin acetate was found to be moderately active against tyrosinase with an inhibition of 62% at 0.1 mg/mL. This activity was lower than that of the positive control, kojic acid (85%).

  11. Reproduction of Amorpha canescens (Fabaceae) and diversity of its bee community in a fragmented landscape.

    Science.gov (United States)

    Slagle, Malinda W; Hendrix, Stephen D

    2009-10-01

    Loss of insect pollinators due to habitat fragmentation often results in negative effects on plant reproduction, but few studies have simultaneously examined variation in the bee community, site characteristics and plant community characteristics to evaluate their relative effects on plant reproduction in a fragmented habitat. We examined the reproduction of a common tallgrass prairie forb, Amorpha canescens (Fabaceae), in large (>40 ha) and small (level characteristics can influence the bee community visiting any one species. Site size, a common predictor of plant reproduction in fragmented habitats did not contribute to any models of fruit set and was only marginally related to bee diversity one year. Andrena quintilis, one of the three oligolectic bee species associated with A. canescens, was abundant at all sites, suggesting it has not been significantly affected by fragmentation. Our results show that the diversity of bees visiting A. canescens is important for maintaining fruit set and that bee visitation is still sufficient for at least some fruit set in all populations, suggesting these small remnants act as floral resource oases for bees in landscapes often dominated by agriculture.

  12. Evolution in the Amphi-Atlantic tropical genus Guibourtia (Fabaceae, Detarioideae), combining NGS phylogeny and morphology.

    Science.gov (United States)

    Tosso, Félicien; Hardy, Olivier J; Doucet, Jean-Louis; Daïnou, Kasso; Kaymak, Esra; Migliore, Jérémy

    2018-03-01

    Tropical rain forests support a remarkable diversity of tree species, questioning how and when this diversity arose. The genus Guibourtia (Fabaceae, Detarioideae), characterized by two South American and 13 African tree species growing in various tropical biomes, is an interesting model to address the role of biogeographic processes and adaptation to contrasted environments on species diversification. Combining whole plastid genome sequencing and morphological characters analysis, we studied the timing of speciation and diversification processes in Guibourtia through molecular dating and ancestral habitats reconstruction. All species except G. demeusei and G. copallifera appear monophyletic. Dispersal from Africa to America across the Atlantic Ocean is the most plausible hypothesis to explain the occurrence of Neotropical Guibourtia species, which diverged ca. 11.8 Ma from their closest African relatives. The diversification of the three main clades of African Guibourtia is concomitant to Miocene global climate changes, highlighting pre-Quaternary speciation events. These clades differ by their reproductive characters, which validates the three subgenera previously described: Pseudocopaiva, Guibourtia and Gorskia. Within most monophyletic species, plastid lineages start diverging from each other during the Pliocene or early Pleistocene, suggesting that these species already arose during this period. The multiple transitions between rain forests and dry forests/savannahs inferred here through the plastid phylogeny in each Guibourtia subgenus address thus new questions about the role of phylogenetic relationships in shaping ecological niche and morphological similarity among taxa. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Anti-inflammatory activity of Adenanthera pavonina L., Fabaceae, in experimental animals

    Directory of Open Access Journals (Sweden)

    Arzumand Ara

    2010-11-01

    Full Text Available Adenanthera pavonina L, Fabaceae alt. Leguminosae, Bengali name 'rakta kombol', is an Indian medicinal plant. It is endemic to Southern China and India, and widely naturalized in Malaysia, Western and Eastern Africa as well as in most islands of both the Pacific and Caribbean regions. This plant has been used in traditional medicine for the treatment of asthma, boil, diarrhoea, gout, inflammations, rheumatism, tumour and ulcers, and as a tonic. The dried and ground bark of A. pavonina L. was extracted, successively, with petroleum ether (PE, dichloromethane (DCM, ethyl acetate (EtOAc and methanol (MeOH, and the resulting extracts were assessed in vivo for anti-inflammatory activity on carrageenan-induced rat hind paw oedema as a model of inflammation. The extracts were administered orally at the doses of 200 and 400 mg/kg body weight, and statistically significant (p<0.001 anti-inflammatory effects were observed in a dose dependant manner. The MeOH extract (400 mg/kg showed 37.10% (p<0.01 inhibition of inflammation at the first hour of the study and, the DCM extract (400 mg/kg exhibited 33.11% (p<0.001 inhibition of inflammation at the third hour of the study which was comparable with that of reference standard drug dichlofenac sodium. The results of this study supported some of the traditional medicinal uses of this plant.

  14. Molecular Phylogeny of Gueldenstaedtia and Tibetia (Fabaceae) and Their Biogeographic Differentiation within Eastern Asia

    Science.gov (United States)

    Xie, Yan-Ping; Meng, Ying; Sun, Hang; Nie, Ze-Long

    2016-01-01

    Tibetia and Gueldenstaedtia are two morphologically similar and small genera in Fabaceae, with distributions largely corresponding to the Sino-Himalayan and Sino-Japanese subkingdoms in eastern Asia, respectively. These two genera have confusing relationships based on morphology; therefore, we aimed to provide a clear understanding of their phylogenetic and biogeographic evolution within eastern Asia. In our investigations we included 88 samples representing five Gueldenstaedtia species, five Tibetia species, and outgroup species were sequenced using five markers (nuclear: ITS; chloroplast: matK, trnL-F, psbA-trnH and rbcL). Our phylogenetic results support (1) the monophyly of Tibetia and of Gueldenstaedtia, respectively; and (2) that Tibetia and Gueldenstaedtia are sister genera. Additionally, our data identified that Tibetia species had much higher sequence variation than Gueldenstaedtia species. Our results suggest that the two genera were separated from each other about 17.23 million years ago, which is congruent with the Himalayan orogeny and the uplift of the Tibetan Plateau in the mid Miocene. The divergence of Tibetia and Gueldenstaedtia is strongly supported by the separation of the Sino-Himalayan and Sino-Japanese region within eastern Asia. In addition, the habitat heterogeneity may accelerate the molecular divergence of Tibetia in the Sino-Himalayan region. PMID:27632535

  15. Anatomical characters of the phyllode and stem of Acacia podalyriifolia A. Cunn. ex G. Don (Fabaceae

    Directory of Open Access Journals (Sweden)

    M.R. Duarte

    Full Text Available The Acacia genus has presented various secondary metabolites, such as tannins, flavonoids, alkaloids and gums. Preparations from different species have been applied for diabetes, gastrointestinal disorders and inflammatory diseases in the traditional medicine and have demonstrated cytotoxic, antimicrobial and antiparasitic activities. Acacia podalyriifolia A. Cunn. ex G. Don (Fabaceae is a small wood, indigenous to Australia and cultivated worldwide for its ornamental feature. This work aimed to characterize the anatomy of the phyllode and stem, in order to contribute to the species identification. The botanical material was fixed, sectioned and prepared according to usual light and scanning microtechniques. The epidermal cells, in surface view, are polygonal and coated with striate and thick cuticle, and filaments of epicuticular wax. Paracytic stomata and unicellular non-glandular trichomes are seen. Palisade and ground parenchymas, and minor collateral bundles with xylem directed alternately to upper and lower sides occur in the blade. The midrib shows two collateral bundles facing each other. The stem, in incipient secondary growth, exhibits epidermis, annular collenchyma, sclerenchymatic sheath and collateral vascular organization. Cells containing phenolic compounds and prisms of calcium oxalate are observed.

  16. Metabolite fingerprinting, pathway analyses, and bioactivity correlations for plant species belonging to the Cornaceae, Fabaceae, and Rosaceae families.

    Science.gov (United States)

    Son, Su Young; Kim, Na Kyung; Lee, Sunmin; Singh, Digar; Kim, Ga Ryun; Lee, Jong Seok; Yang, Hee-Sun; Yeo, Joohong; Lee, Sarah; Lee, Choong Hwan

    2016-09-01

    A multi-parallel approach gauging the mass spectrometry-based metabolite fingerprinting coupled with bioactivity and pathway evaluations could serve as an efficacious tool for inferring plant taxonomic orders. Thirty-four species from three plant families, namely Cornaceae (7), Fabaceae (9), and Rosaceae (18) were subjected to metabolite profiling using gas chromatography-time-of-flight-mass spectrometry (GC-TOF-MS) and ultrahigh performance liquid chromatography-linear trap quadrupole-ion trap-mass spectrometry (UHPLC-LTQ-IT-MS/MS), followed by multivariate analyses to determine the metabolites characteristic of these families. The partial least squares discriminant analysis (PLS-DA) revealed the distinct clustering pattern of metabolites for each family. The pathway analysis further highlighted the relatively higher proportions of flavonols and ellagitannins in the Cornaceae family than in the other two families. Higher levels of phenolic acids and flavan-3-ols were observed among species from the Rosaceae family, while amino acids, flavones, and isoflavones were more abundant among the Fabaceae family members. The antioxidant activities of plant extracts were measured using ABTS, DPPH, and FRAP assays, and indicated that extracts from the Rosaceae family had the highest activity, followed by those from Cornaceae and Fabaceae. The correlation map analysis positively links the proportional concentration of metabolites with their relative antioxidant activities, particularly in Cornaceae and Rosaceae. This work highlights the pre-eminence of the multi-parallel approach involving metabolite profiling and bioactivity evaluations coupled with metabolic pathways as an efficient methodology for the evaluation of plant phylogenies.

  17. Discovery of cyclotides in the fabaceae plant family provides new insights into the cyclization, evolution, and distribution of circular proteins.

    Science.gov (United States)

    Poth, Aaron G; Colgrave, Michelle L; Philip, Reynold; Kerenga, Bomai; Daly, Norelle L; Anderson, Marilyn A; Craik, David J

    2011-04-15

    Cyclotides are plant proteins whose defining structural features are a head-to-tail cyclized backbone and three interlocking disulfide bonds, which in combination are known as a cyclic cystine knot. This unique structural motif confers cyclotides with exceptional resistance to proteolysis. Their endogenous function is thought to be as plant defense agents, associated with their insecticidal and larval growth-inhibitory properties. However, in addition, an array of pharmaceutically relevant biological activities has been ascribed to cyclotides, including anti-HIV, anthelmintic, uterotonic, and antimicrobial effects. So far, >150 cyclotides have been elucidated from members of the Rubiaceae, Violaceae, and Cucurbitaceae plant families, but their wider distribution among other plant families remains unclear. Clitoria ternatea (Butterfly pea) is a member of plant family Fabaceae and through its usage in traditional medicine to aid childbirth bears similarity to Oldenlandia affinis, from which many cyclotides have been isolated. Using a combination of nanospray and matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) analyses, we examined seed extracts of C. ternatea and discovered cyclotides in the Fabaceae, the third-largest family of flowering plants. We characterized 12 novel cyclotides, thus expanding knowledge of cyclotide distribution and evolution within the plant kingdom. The discovery of cyclotides containing novel sequence motifs near the in planta cyclization site has provided new insights into cyclotide biosynthesis. In particular, MS analyses of the novel cyclotides from C. ternatea suggest that Asn to Asp variants at the cyclization site are more common than previously recognized. Moreover, this study provides impetus for the examination of other economically and agriculturally significant species within Fabaceae, now the largest plant family from which cyclotides have been described.

  18. Three new species of Horismenus Walker (Hymenoptera: Eulophidae) associated with seed pods of Pithecellobium dulce (Fabaceae).

    Science.gov (United States)

    Pikart, Tiago G; Costa, Valmir A; Hansson, Christer; Zanuncio, José C; Serrão, José E

    2015-08-04

    Horismenus abnormicaulis sp. nov., H. patensis sp. nov. and H. zuleidae sp. nov. (Hymenoptera: Eulophidae), all authored by Pikart, Costa & Hansson, are described from material obtained from seed pods of Pithecellobium dulce (Roxb.) Benth. (Fabaceae) collected in Northeastern Brazil. The seed pods were infested with larvae of Coleoptera (Chrysomelidae (Bruchinae) and Curculionidae). The associations of the Horismenus species and the beetle larvae have not been established. Morphological similarities between these new species and previously described species with host known suggest that H. patensis and H. zuleidae are primary parasitoids of Bruchinae, whereas H. abnormicaulis may act as a hyperparasitoid on other Horismenus species. The three species are compared with similar species of Horismenus.

  19. Eriosema (Fabaceae) Species Represent a Rich Source of Flavonoids with Interesting Pharmacological Activities.

    Science.gov (United States)

    Awouafack, Maurice Ducret; Tane, Pierre; Spiteller, Michael; Eloff, Jacobus Nicolaas

    2015-07-01

    Many flavonoids have so far been isolated as main secondary metabolites in plant species of the genus Eriosema (Fabaceae), which contains approximately 160 species. A total of 52 flavonoids including isoflavones, dihydroflavonols, flavonols, flavanones, dihydrochalcones, isoflavanone and their pyrano or glucoside derivatives were isolated and characterized from the five species of this genus investigated to date. Total synthesis and semi-synthesis (acetylation, methylation, hydrogenation, and cyclization) of some isolated flavonoids were reported. Due to several significant pharmacological properties (antimicrobial, cytotoxicity, anti-mycobacterial, antioxidant, antiviral, erectile-dysfunction, vasodilatory and hypoglycemic) of the isolated flavonoids and derivatives, more scientists should be interested in investigating Eriosema species. The present review is the first to document all flavonoids that have been reported from the genus Eriosema to date together with their synthetic and semi-synthetic derivatives, and their pharmacological properties. Dihydrochalcones, which are precursors of other classes of flavonoids, are very rare in natural sources and their isolation from Eriosema species may explain the large number of flavonoids found in this genus. It appears that isoflavone could be a marker for species in this genus. The 83 flavonoids (1-83) documented include 52 isolates, 31 semi-synthetic and 3 totally synthetic derivatives. Data were obtained from Google scholar, Pubmed, Scifinder, Sciencedirect, and Scopus. With 52 different flavonoids isolated from only 5 of the approximately 160 species it shows the remarkable chemical diversity of this genus. This compilation of the biological activities and chemical composition may renew the interest of pharmacologists and phytochemists in this genus.

  20. Role of the lens in controlling physical dormancy break and germination of Delonix regia (Fabaceae: Caesalpinioideae).

    Science.gov (United States)

    Jaganathan, G K; Wu, G-R; Han, Y-Y; Liu, B L

    2017-01-01

    Physical dormancy occurs in all three subfamilies of Fabaceae, namely Mimosoideae, Papilionoideae and Caesalpinioideae, making it one of the largest plant families in terms of number of species with physical dormancy. However, little is known about the water gap structure and germination ecology of species in Caesalpinioideae. Freshly collected seeds of Delonix regia (Caesalpinioideae) did not imbibe water, thus they had physical dormancy. Both dry heat and wet heat were effective in breaking dormancy, however, longer duration was required at 80 °C and shorter duration at 90 °C. Seeds buried in the field for 2 years germinated to 21% and 42% after the first and second summer, respectively, compared with 3% germination in seeds at the time of maturity. Seeds incubated at 15/60 °C in the laboratory (mimicking summer conditions) for 3 months supported this conclusion, as dormancy was relieved in 18% and 24% of seeds stored dry and watered intermediately, respectively. All the dormancy breaking treatments resulted in lifting of palisade layers in the lens region to form a circular lid-like opening, i.e. water gap (Type II simple). Blocking experiments confirmed that water entered only through the lens and no secondary water entry point was observed. No apparent changes in morphology/anatomy of the hilum region were noted in dormant and non-dormant (water permeable) seeds. These results suggest that summer temperatures could open the lens in a proportion of seeds every year and that germination occurs during the subsequent wet season in the tropics. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  1. Large-scale phylogeography of the disjunct Neotropical tree species Schizolobium parahyba (Fabaceae-Caesalpinioideae).

    Science.gov (United States)

    Turchetto-Zolet, Andreia C; Cruz, Fernanda; Vendramin, Giovanni G; Simon, Marcelo F; Salgueiro, Fabiano; Margis-Pinheiro, Marcia; Margis, Rogerio

    2012-10-01

    Neotropical rainforests exhibit high levels of endemism and diversity. Although the evolutionary genetics of plant diversification has garnered increased interest, phylogeographic studies of widely distributed species remain scarce. Here we describe chloroplast and nuclear variation patterns in Schizolobium parahyba (Fabaceae), a widespread tree in Neotropical rainforests that harbor two varieties with a disjunct distribution. Chloroplast and nuclear sequence analyses yielded 21 and 4 haplotypes, respectively. Two genetic diversity centers that correlate with the two known varieties were identified: the Southeastern Atlantic forest and the Amazonian basin. In contrast, the populations from southern and northeastern Atlantic forests and Andean-Central American forests exhibited low levels of genetic diversity and divergent haplotypes, likely related to historical processes that impact the flora and fauna in these regions, such as a founder's effect after dispersion and demographic expansion. Phylogeographic and demographic patterns suggest that episodes of genetic isolation and dispersal events have shaped the evolutionary history for this species, and different patterns have guided the evolution of S. parahyba. Moreover, the results of this study suggest that the dry corridor formed by Cerrado and Caatinga ecoregions and the Andean uplift acted as barriers to this species' gene flow, a picture that may be generalized to most of the plant biodiversity tropical woodlands and forests. These results also reinforce the importance of evaluating multiple genetic markers for a more comprehensive understanding of population structure and history. Our results provide insight into the conservation efforts and ongoing work on the genetics of population divergence and speciation in these Neotropical rainforests. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Endoreduplication intensity as a marker of seed developmental stage in the Fabaceae.

    Science.gov (United States)

    Rewers, Monika; Sliwinska, Elwira

    2012-12-01

    Flow cytometry (FCM) can be used to study cell cycle activity in developing, mature and germinating seeds. It provides information about a seed's physiological state and therefore can be used by seed growers for assessing optimal harvest times and presowing treatments. Because an augmented proportion of 4C nuclei usually is indicative of high mitotic activity, the 4C/2C ratio is commonly used to follow the progress of seed development and germination. However, its usefulness for polysomatic (i.e., containing cells with different DNA content) seeds is questioned. Changes in cell cycle/endoreduplication activity in developing seeds of five members of the Fabaceae were studied to determine a more suitable marker of seed developmental stages for polysomatic species based on FCM measurements. Seeds of Phaseolus vulgaris, Medicago sativa, Pisum sativum, Vicia sativa, and Vicia faba var. minor were collected 20, 30, 40, 50, and 60 days after flowering (DAF), embryos were isolated and the proportion of nuclei with different DNA contents in the embryo axis and cotyledon was established. The ratios 4C/2C and (Σ>2C)/2C were calculated. Dried seeds were subjected to laboratory germination tests following international seed testing association (ISTA) rules. Additionally, the absolute nuclear DNA content was estimated in the leaves of the studied species. During seed development nuclei with DNA contents from 2C to 128C were detected; the endopolyploidy pattern depended on the species, seed organ and developmental stage. The cell cycle/endoreduplication parameters correlated negatively with genome size. The (Σ>2C)/2C ratio in the cotyledons reflected the seed developmental stage and corresponded with seed germinability. Therefore, this ratio is recommended as a marker in polysomatic seed research and production instead of the 4C/2C ratio, which does not consider the occurrence of endopolyploid cells. Copyright © 2012 International Society for Advancement of Cytometry.

  3. Leishmanicidal Metabolites from Cochliobolus sp., an Endophytic Fungus Isolated from Piptadenia adiantoides (Fabaceae)

    Science.gov (United States)

    Campos, Fernanda Fraga; Rosa, Luiz Henrique; Cota, Betania Barros; Caligiorne, Rachel Basques; Teles Rabello, Ana Lúcia; Alves, Tânia Maria Almeida; Rosa, Carlos Augusto; Zani, Carlos Leomar

    2008-01-01

    Protozoan parasites belonging to genera Leishmania and Trypanosoma are the etiological agents of severe neglected tropical diseases (NTDs) that cause enormous social and economic impact in many countries of tropical and sub-tropical areas of the world. In our screening program for new drug leads from natural sources, we found that the crude extract of the endophytic fungus Cochliobolus sp. (UFMGCB-555) could kill 90% of the amastigote-like forms of Leishmania amazonensis and inhibit by 100% Ellman's reagent reduction in the trypanothione reductase (TryR) assay, when tested at 20 µg mL−1. UFMGCB-555 was isolated from the plant Piptadenia adiantoides J.F. Macbr (Fabaceae) and identified based on the sequence of the internally transcribed spacer (ITS) regions of its ribosomal DNA. The chromatographic fractionation of the extract was guided by the TryR assay and resulted in the isolation of cochlioquinone A and isocochlioquinone A. Both compounds were active in the assay with L. amazonensis, disclosing EC50 values (effective concentrations required to kill 50% of the parasite) of 1.7 µM (95% confidence interval = 1.6 to 1.9 µM) and 4.1 µM (95% confidence interval = 3.6 to 4.7 µM), respectively. These compounds were not active against three human cancer cell lines (MCF-7, TK-10, and UACC-62), indicating some degree of selectivity towards the parasites. These results suggest that cochlioquinones are attractive lead compounds that deserve further investigation aiming at developing new drugs to treat leishmaniasis. The findings also reinforce the role of endophytic fungi as an important source of compounds with potential to enter the pipeline for drug development against NTDs. PMID:19079599

  4. Effects of Retama raetam (Forssk. Webb & Berthel. (Fabaceae on the central nervous system in experimental animals

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    Al-Tubuly Rida A.

    2011-01-01

    Full Text Available Retama raetam (Forssk. Webb & Berthel. (Fabaceae, commonly known as ‘raetam’ or ‘broom bush’, is a desert shrub that grows abundantly in North-African countries, Palestine and Syria. Traditionally, this plant has been used as an abortifacient, a purgative and a vermifuge. In the present study, the effect of the methanol (MeOH extract of the aerial parts of R. raetam on the central nervous system (CNS has been evaluated using a mice model. In the photoelectrical cell test, the extract of R. raetam (ERR at a dose of 125 mg/kg body weight did not exhibit any effect on the spontaneous motor activity in mice. At a dose of 250 mg/kg body weight, ERR increased ambulatory movement, but had no effect on the non-ambulatory movement, while a dose of 375 mg/kg body weight decreased both ambulatory and non-ambulatory movements. The effect of ERR on the anxiety levels and behaviors of mice was investigated using the elevated plus-maze test. At doses of 125, 250 and 375 mg/kg body weight, ERR decreased anxiety levels without showing an effect on the total activity; it did not affect anxiety levels but increased the total activity; it increased anxiety levels and decreased the total activity, respectively. In the diazepam-induced sleep test, ERR increased the onset of sleep without affecting the duration of sleep at the dose of 250 mg/kg body weight. The dose of 375 mg/kg body weight decreased the onset of sleep while increasing the duration of sleep. ERR did not exhibit any effect on the diazepam-induced sleep in the presence of flumazenil or picrotoxin.

  5. A review of the taxonomy, ethnobotany, chemistry and pharmacology of Sutherlandia frutescens (Fabaceae).

    Science.gov (United States)

    van Wyk, B-E; Albrecht, C

    2008-10-28

    Sutherlandia frutescens (tribe Galegeae, Fabaceae), a popular plant in traditional medicine, is indigenous to South Africa, Lesotho, southern Namibia and southeastern Botswana. It is chemically, genetically and geographically extremely variable and has been divided into three subspecies and several regional forms. A second species, Sutherlandia tomentosa, is localized along the Cape coast. Sutherlandia is sometimes treated as part of the genus Lessertia. There are numerous vernacular names and a wide diversity of uses, including poor appetite, indigestion, stomach complaints, dysentery, colds, influenza, kidney conditions, fever, diabetes, internal cancers, uterine troubles, liver conditions, backache, rheumatoid arthritis, urinary tract infections, stress and anxiety, dropsy and heart failure. Notable is the use as a bitter tonic ("blood purifier"), anti-stress medication ('musa-pelo) and, at least since 1895, specifically as a cancer tonic (both as treatment and as prophylaxis). Externally it is applied to haemorrhoids, inflamed wounds and eye infections. Recent in vitro and in vivo studies have shown antiproliferative, anti-HIV, anti-diabetic, anti-inflammatory, analgesic, antibacterial, anti-stress, anticonvulsant and antithrombotic activities. Aqueous extracts often differ in activity from organic solvent extracts. The presence of high levels of free amino acids, non-protein amino acids such as canavanine and GABA, the cyclitol pinitol, flavonols and triterpenes (including SU1, a cycloartane-type triterpene saponin) provide plausible hypotheses on how these compounds, individually or collectively, may be responsible for the reputed efficacy in a wide range of ailments. Results of animal studies, as well as a phase I clinical study, have shown no indications of toxicity. Sufficient preclinical data are now available to justify controlled clinical studies.

  6. Ecology and management of Pericopsis elata (Harms Meeuwen (Fabaceae populations: a review

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    Bourland, N.

    2012-01-01

    Full Text Available Pericopsis elata (Fabaceae is a valuable timber species occurring in moist semi-deciduous African forests. While it is at present substantially reduced, the tree's natural distribution previously covered several distinct areas from Côte d'Ivoire to the Democratic Republic of Congo. This species has been logged since the second half of the 20th century. Because it suffers from a lack of regeneration, P. elata is now included in CITES Appendix II and is recorded as "Endangered A1cd" on the IUCN Red List. As with other long-lived light-demanding species, the survival of P. elata may have been favored by important disturbances that occurred in the Congo Basin during the last millennia. While both international trade and industrial uses of the wood of P. elata are well documented, information about its ecology are very sparse or contradictory, and even absent in some cases (e.g., regarding its effective flowering diameter. Furthermore, data describing the management of P. elata are scarce, including potential solutions to compensate for the deficit of natural regeneration. Along the same lines, genetic studies still remain at an early stage and only vague hypotheses have been offered to explain the origins of the tree's populations. We emphasize the need for new research on those topics. Further studies would be useful in deciding whether P. elata populations can continue to be logged without the species being threatened with extinction. Finally, such research needs to target effective and inexpensive management procedures that could secure the future of the species in a logging context.

  7. Insect Seed Predators in Erythrina falcata (Fabaceae): Identification of Predatory Species and Ecological Consequences of Asynchronous Flowering.

    Science.gov (United States)

    Pereira, C M; Moura, M O; Da-Silva, P R

    2014-06-01

    Seed predation by insects exerts negative effects on plant reproduction by limiting the supply of seeds and preventing germination. Seed predators of the family Fabaceae are usually generalists, which increases the rate of predation. One strategy to minimize seed predation, developed by plants from temperate regions, is "escape in time," i.e., flowering before or after the peak of predation. For tropical species, few studies have investigated the strategies used by plants to minimize seed predation. Here, using Erythrina falcata, a tropical species of Fabaceae, we test three main hypotheses: (i) escape in time is a mechanism used by E. falcata to minimize seed predation, (ii) the predators of E. falcata seeds are generalists, and (iii) the biometric variables of the pods can influence seed predation. In order to test these hypotheses, we determined the flowering time of E. falcata, rate of seed predation, the predators insects, and biometric variables of the pods. The analyzed trees were grouped into three classes: "early," "peak," and "late" flowering. The average seed predation rates on trees in the early and late classes were 65% and 50%, respectively, and in the peak class, 80%; thus, our first hypothesis can be accepted. Three species of Lepidoptera and two of Coleoptera were found preying on E. falcata seeds. These species were observed to be generalist predators; thus, our second hypothesis can be accepted. The biometric variables of the pods cannot influence seed predation rate. The ecological consequences of asynchronous flowering on plants and insects are discussed.

  8. Hedysarum L. (Fabaceae: Hedysareae) Is Not Monophyletic - Evidence from Phylogenetic Analyses Based on Five Nuclear and Five Plastid Sequences.

    Science.gov (United States)

    Liu, Pei-Liang; Wen, Jun; Duan, Lei; Arslan, Emine; Ertuğrul, Kuddisi; Chang, Zhao-Yang

    2017-01-01

    The legume family (Fabaceae) exhibits a high level of species diversity and evolutionary success worldwide. Previous phylogenetic studies of the genus Hedysarum L. (Fabaceae: Hedysareae) showed that the nuclear and the plastid topologies might be incongruent, and the systematic position of the Hedysarum sect. Stracheya clade was uncertain. In this study, phylogenetic relationships of Hedysarum were investigated based on the nuclear ITS, ETS, PGDH, SQD1, TRPT and the plastid psbA-trnH, trnC-petN, trnL-trnF, trnS-trnG, petN-psbM sequences. Both nuclear and plastid data support two major lineages in Hedysarum: the Hedysarum s.s. clade and the Sartoria clade. In the nuclear tree, Hedysarum is biphyletic with the Hedysarum s.s. clade sister to the Corethrodendron + Eversmannia + Greuteria + Onobrychis clade (the CEGO clade), whereas the Sartoria clade is sister to the genus Taverniera DC. In the plastid tree, Hedysarum is monophyletic and sister to Taverniera. The incongruent position of the Hedysarum s.s. clade between the nuclear and plastid trees may be best explained by a chloroplast capture hypothesis via introgression. The Hedysarum sect. Stracheya clade is resolved as sister to the H. sect. Hedysarum clade in both nuclear and plastid trees, and our analyses support merging Stracheya into Hedysarum. Based on our new evidence from multiple sequences, Hedysarum is not monophyletic, and its generic delimitation needs to be reconsidered.

  9. Carbon and nutrient stocks of three Fabaceae trees used for forest restoration and subjected to fertilization in Amazonia.

    Science.gov (United States)

    Jaquetti, Roberto K; Gonçalves, José Francisco C

    2017-01-01

    Amazonia is crucial to global carbon cycle. Deforestation continues to be one of the main causes of the release of C into the atmosphere, but forest restoration plantations can reverse this scenario. However, there is still diffuse information about the C and nutrient stocks in the vegetation biomass. We investigated the carbon and nutrient stocks of Fabaceae trees (Inga edulis, Schizolobium amazonicum and Dipteryx odorata) subjected to fertilization treatments (T1 - no fertilization; T2 - chemical; T3 - organic; and T4 - organic and chemical fertilization) in a degraded area of the Balbina Hydroelectric Dam, AM - Brazil. As an early successional species, I. edulis stocked more C and nutrients than the other two species independent of the fertilization treatment, and S. amazonicum stocked more C than D. odorata under T1 and T4. The mixed species plantation had the potential to stock 4.1 Mg C ha-1 year-1, while I. edulis alone could stock 9.4 Mg C ha-1 year-1. Mixing species that rapidly assimilate C and are of significant ecological and commercial value (e.g., Fabaceae trees) represents a good way to restore degraded areas. Our results suggest that the tested species be used for forest restoration in Amazonia.

  10. Pollen grain morphology of Fabaceae in the Special Protection Area (SPA) Pau-de-Fruta, Diamantina, Minas Gerais, Brazil.

    Science.gov (United States)

    Luz, Cynthia F P da; Maki, Erica S; Horák-Terra, Ingrid; Vidal-Torrado, Pablo; Mendonça Filho, Carlos Victor

    2013-01-01

    The presented paper considered the pollen morphology of thirteen species belonging to seven genera of the Fabaceae family occurring in the Pau-de-Fruta Special Protection Area (SPA), Diamantina, state of Minas Gerais, Brazil. The pollen grains of six species of Chamaecrista [C. cathartica (Mart.) H.S. Irwin & Barneby, C. debilis Vogel, C. flexuosa (L.) Greene, C. hedysaroides (Vogel) H.S. Irwin & Barneby, C. glandulosa (L.) Greene, and C. papillata H.S. Irwin & Barneby] have a similar morphology, characterized by three long colporated apertures with a central constriction. The species share specific morphological features regarding pollen size, endoaperture type (circular, lalongate or lolongate) and SEM ornamentation patterns of the exine (rugulate with perforations or perforate). Andira fraxinifolia Benth., Dalbergia miscolobium Benth, Galactia martii DC, Periandra mediterranea (Vell.) Taub., Senna rugosa (G.Don) H.S. Irwin & Barneby and Zornia diphylla (L.) Pers showed different pollen types in small to large size; oblate spheroidal to prolate form; colpus or colporus apertures; circular, lalongate or lolongate endoapertures and distinctive SEM ornamentation patterns of the exine (perforate, microreticulate, reticulate or rugulate with perforations). Only Stryphnodendron adstringens (Mart.) Coville presents polyads. The pollen morphology variation of these species allowed the Fabaceae family to be characterized as eurypalynous in the SPA Pau-de-Fruta.

  11. Hedysarum L. (Fabaceae: Hedysareae) Is Not Monophyletic – Evidence from Phylogenetic Analyses Based on Five Nuclear and Five Plastid Sequences

    Science.gov (United States)

    Liu, Pei-Liang; Wen, Jun; Duan, Lei; Arslan, Emine; Ertuğrul, Kuddisi; Chang, Zhao-Yang

    2017-01-01

    The legume family (Fabaceae) exhibits a high level of species diversity and evolutionary success worldwide. Previous phylogenetic studies of the genus Hedysarum L. (Fabaceae: Hedysareae) showed that the nuclear and the plastid topologies might be incongruent, and the systematic position of the Hedysarum sect. Stracheya clade was uncertain. In this study, phylogenetic relationships of Hedysarum were investigated based on the nuclear ITS, ETS, PGDH, SQD1, TRPT and the plastid psbA-trnH, trnC-petN, trnL-trnF, trnS-trnG, petN-psbM sequences. Both nuclear and plastid data support two major lineages in Hedysarum: the Hedysarum s.s. clade and the Sartoria clade. In the nuclear tree, Hedysarum is biphyletic with the Hedysarum s.s. clade sister to the Corethrodendron + Eversmannia + Greuteria + Onobrychis clade (the CEGO clade), whereas the Sartoria clade is sister to the genus Taverniera DC. In the plastid tree, Hedysarum is monophyletic and sister to Taverniera. The incongruent position of the Hedysarum s.s. clade between the nuclear and plastid trees may be best explained by a chloroplast capture hypothesis via introgression. The Hedysarum sect. Stracheya clade is resolved as sister to the H. sect. Hedysarum clade in both nuclear and plastid trees, and our analyses support merging Stracheya into Hedysarum. Based on our new evidence from multiple sequences, Hedysarum is not monophyletic, and its generic delimitation needs to be reconsidered. PMID:28122062

  12. Carbon and nutrient stocks of three Fabaceae trees used for forest restoration and subjected to fertilization in Amazonia

    Directory of Open Access Journals (Sweden)

    ROBERTO K. JAQUETTI

    2017-08-01

    Full Text Available ABSTRACT Amazonia is crucial to global carbon cycle. Deforestation continues to be one of the main causes of the release of C into the atmosphere, but forest restoration plantations can reverse this scenario. However, there is still diffuse information about the C and nutrient stocks in the vegetation biomass. We investigated the carbon and nutrient stocks of Fabaceae trees (Inga edulis, Schizolobium amazonicum and Dipteryx odorata subjected to fertilization treatments (T1 - no fertilization; T2 - chemical; T3 - organic; and T4 - organic and chemical fertilization in a degraded area of the Balbina Hydroelectric Dam, AM - Brazil. As an early successional species, I. edulis stocked more C and nutrients than the other two species independent of the fertilization treatment, and S. amazonicum stocked more C than D. odorata under T1 and T4. The mixed species plantation had the potential to stock 4.1 Mg C ha-1 year-1, while I. edulis alone could stock 9.4 Mg C ha-1 year-1. Mixing species that rapidly assimilate C and are of significant ecological and commercial value (e.g., Fabaceae trees represents a good way to restore degraded areas. Our results suggest that the tested species be used for forest restoration in Amazonia.

  13. Andiroxylon Thanobolensis Sp.Nov. A New Species of Fossil Wood of Family Fabaceae from Manchar Formation Exposed Near Thanobola Khan, District Jamshoro, Sindh, Pakistan

    International Nuclear Information System (INIS)

    Khan, S. A.; Ahmed, B.; Tahir, S. S.

    2016-01-01

    Andiroxylon thanobolensis sp. nov., a new silicified wood has been described and identified from Tertiary Manchar formation exposed near Thanobola Khan, district Jamshoro, Sindh, Pakistan. The xylotomical features of present fossil shows close resemblance with the genus Andira of the Family Fabaceae. The absence of growth ring indicated that plants were growing in tropical type of climate. (author)

  14. Description of the early stages of Eccopsis galapagana Razowski & Landry (Lepidoptera: Tortricidae), a defoliator of Prosopis juliflora (Sw.) DC (Fabaceae) in Colombia

    Science.gov (United States)

    The biology and early stages of Eccopsis galapagana Razowski & Landry are described and illustrated for the first time; details of the adults also are provided. Under outbreak conditions, the species has become a serious pest of algarrobo tree (Prosopis juliflora (Sw.) DC.; Fabaceae) in Colombia. Al...

  15. Divergence and diversification in North American Psoraleeae (Fabaceae) due to climate change

    Science.gov (United States)

    Egan, Ashley N; Crandall, Keith A

    2008-01-01

    Background Past studies in the legume family (Fabaceae) have uncovered several evolutionary trends including differential mutation and diversification rates across varying taxonomic levels. The legume tribe Psoraleeae is shown herein to exemplify these trends at the generic and species levels. This group includes a sizable diversification within North America dated at approximately 6.3 million years ago with skewed species distribution to the most recently derived genus, Pediomelum, suggesting a diversification rate shift. We estimate divergence dates of North American (NAm) Psoraleeae using Bayesian MCMC sampling in BEAST based on eight DNA regions (ITS, waxy, matK, trnD-trnT, trnL-trnF, trnK, trnS-trnG, and rpoB-trnC). We also test the hypothesis of a diversification rate shift within NAm Psoraleeae using topological and temporal methods. We investigate the impact of climate change on diversification in this group by (1) testing the hypothesis that a shift from mesic to xeric habitats acted as a key innovation and (2) investigating diversification rate shifts along geologic time, discussing the impact of Quaternary climate oscillations on diversification. Results NAm Psoraleeae represents a recent, rapid radiation with several genera originating during the Pleistocene, 1 to 2 million years ago. A shift in diversification rate is supported by both methods with a 2.67-fold increase suggested around 2 million years ago followed by a 8.73-fold decrease 440,000 years ago. The hypothesis that a climate regime shift from mesic to xeric habitats drove increased diversification in affected taxa was not supported. Timing of the diversification rate increase supports the hypothesis that glaciation-induced climate changes during the Quaternary influenced diversification of the group. Nonrandom spatial diversification also exists, with greater species richness in the American Southwest. Conclusion This study outlines NAm Psoraleeae as a model example of a recent, rapid

  16. Assessment of cadmium accumulation, toxicity, and tolerance in Brassicaceae and Fabaceae plants--implications for phytoremediation.

    Science.gov (United States)

    Anjum, Naser A; Umar, Shahid; Iqbal, Muhammad

    2014-09-01

    This study, based on a greenhouse pot culture experiment conducted with 15-day-old rapeseed (Brassica campestris L. cv. Pusa Gold; family Brassicaceae) and moong bean (Vigna radiata L. Wilczek cv. Pusa Ratna; family Fabaceae) plants treated with cadmium (Cd) concentrations (0, 50, and 100 mg kg(-1) soil), investigates their potential for Cd accumulation and tolerance, and dissects the underlying basic physiological/biochemical mechanisms. In both species, plant dry mass decreased, while Cd concentration of both root and shoot increased with increase in soil Cd. Roots harbored a higher amount of Cd (vs. shoot) in B. campestris, while the reverse applied to V. radiata. By comparison, root Cd concentration was higher in B. campestris than in V. radiata. The high Cd concentrations in B. campestris roots and V. radiata shoots led to significant elevation in oxidative indices, as measured in terms of electrolyte leakage, H2O2 content, and lipid peroxidation. Both plants displayed differential adaptation strategies to counteract the Cd burden-caused anomalies in their roots and shoots. In B. campestris, increasing Cd burden led to a significantly decreased reduced glutathione (GSH) content but a significant increase in activities of GSH reductase (GR), GSH peroxidase (GPX), and GSH sulfotransferase (GST). However, in V. radiata, increasing Cd burden caused significant increase in GSH content and GR activity, but a significant decline in activities of GPX and GST. Cross talks on Cd burden of tissues and the adapted Cd tolerance strategies against Cd burden-accrued toxicity indicated that B. campestris and V. radiata are good Cd stabilizer and Cd extractor, respectively, wherein a fine tuning among the major components (GR, GPX, GST, GSH) of the GSH redox system helped the plants to counteract differentially the Cd load-induced anomalies in tissues. On the whole, the physiological/biochemical characterization of the B. campestris and V. radiata responses to varying Cd

  17. Biogeochemistry and biodiversity interact to govern N2 fixers (Fabaceae) across Amazon tropical forests

    Science.gov (United States)

    Batterman, Sarah; Hedin, Lars; Lloyd, Jon; Quesada, Beto

    2015-04-01

    Dinitrogen (N2)-fixing trees in the Fabaceae fulfill a central role in tropical rainforests by supplying nitrogen from the atmosphere, yet whether they will support a forest CO2 sink in the future by alleviating nitrogen limitation may depend on whether and how they are controlled by local environmental conditions. Theory predicts that soil nutrients govern the function of N2 fixers, yet there have been no large-scale field-based tests of this idea. Moreover, recent findings indicate that N2-fixing species behave differently in biogeochemical cycles, suggesting that any environmental control may differ by species, and that the diversity of N2-fixing trees may be critical for ensuring tropical forest function. In this talk, we will use the RAINFOR dataset of 108 (~1.0 ha) lowland tropical rainforest plots from across the Amazon Basin to test whether the abundance and diversity of N2-fixing trees are controlled by soil nutrient availability (i.e., increasing with phosphorus and decreasing with nitrogen), or if fixer abundance and diversity simply follow the dynamics of all tree species. We also test an alternative - but not mutually exclusive - hypothesis that the governing factor for fixers is forest disturbance. Results show a surprising lack of control by local nutrients or disturbance on the abundance or diversity of N2 fixers. The dominant driver of fixer diversity was the total number of tree species, with fixers comprising 10% of all species in a forest plot (R2 = 0.75, linear regression). When considering the dominant taxa of N2 fixers (Inga, Swartzia, Tachigali) alone, environmental factors (nitrogen, phosphorus and disturbance) became important and clearly governed their abundance. These taxa, which contain >60% of N2-fixing trees in the data set, appear to have evolved to specialize in different local environmental conditions. The strong biogeochemistry-by-biodiversity interaction observed here points to a need to consider individual species or taxa of N2

  18. Divergence and diversification in North American Psoraleeae (Fabaceae due to climate change

    Directory of Open Access Journals (Sweden)

    Crandall Keith A

    2008-12-01

    Full Text Available Abstract Background Past studies in the legume family (Fabaceae have uncovered several evolutionary trends including differential mutation and diversification rates across varying taxonomic levels. The legume tribe Psoraleeae is shown herein to exemplify these trends at the generic and species levels. This group includes a sizable diversification within North America dated at approximately 6.3 million years ago with skewed species distribution to the most recently derived genus, Pediomelum, suggesting a diversification rate shift. We estimate divergence dates of North American (NAm Psoraleeae using Bayesian MCMC sampling in BEAST based on eight DNA regions (ITS, waxy, matK, trnD-trnT, trnL-trnF, trnK, trnS-trnG, and rpoB-trnC. We also test the hypothesis of a diversification rate shift within NAm Psoraleeae using topological and temporal methods. We investigate the impact of climate change on diversification in this group by (1 testing the hypothesis that a shift from mesic to xeric habitats acted as a key innovation and (2 investigating diversification rate shifts along geologic time, discussing the impact of Quaternary climate oscillations on diversification. Results NAm Psoraleeae represents a recent, rapid radiation with several genera originating during the Pleistocene, 1 to 2 million years ago. A shift in diversification rate is supported by both methods with a 2.67-fold increase suggested around 2 million years ago followed by a 8.73-fold decrease 440,000 years ago. The hypothesis that a climate regime shift from mesic to xeric habitats drove increased diversification in affected taxa was not supported. Timing of the diversification rate increase supports the hypothesis that glaciation-induced climate changes during the Quaternary influenced diversification of the group. Nonrandom spatial diversification also exists, with greater species richness in the American Southwest. Conclusion This study outlines NAm Psoraleeae as a model example

  19. Ormosioxylon chinjiensis sp. nov., a new fossil wood of family Fabaceae from the Chinji formation Salt Range Punjab, Pakistan

    International Nuclear Information System (INIS)

    Soomro, N.; Arain, B. A.; Rajput, T. M.; Tahir, S. S.

    2016-01-01

    The present work deals with anatomical study of fossil wood collected from the Chinji formation (72 degree 22 min E, 32 degree 4 min N) of Miocene age exposed at the Chinji National Reserve at salt Range Punjab, Pakistan. The material consisted of a single piece of petrified wood. Taxonomical characters of the fossil wood were compared with modern and fossil wood. The sample wood was found comparable to the family Fabaceae. The closest resemblance of the fossil wood was with the wood of Ormosia. The fossil wood under investigation showed close resemblance of vessels, fibers, parenchyma and xylem rays, with the genus Ormosia but shows differences from already reported species of this genus. Hence it is described as a new species as Ormosioxylon chinjiensis sp. nov. The specific epithet refers to Chinji Formation from which the fossil wood is collected. (author)

  20. The position of prenylation of isoflavonoids and stilbenoids from legumes (Fabaceae) modulates the antimicrobial activity against Gram positive pathogens.

    Science.gov (United States)

    Araya-Cloutier, Carla; den Besten, Heidy M W; Aisyah, Siti; Gruppen, Harry; Vincken, Jean-Paul

    2017-07-01

    The legume plant family (Fabaceae) is a potential source of antimicrobial phytochemicals. Molecular diversity in phytochemicals of legume extracts was enhanced by germination and fungal elicitation of seven legume species, as established by RP-UHPLC-UV-MS. The relationship between phytochemical composition, including different types of skeletons and substitutions, and antibacterial properties of extracts was investigated. Extracts rich in prenylated isoflavonoids and stilbenoids showed potent antibacterial activity against Listeria monocytogenes and methicillin-resistant Staphylococcus aureus at concentrations between 0.05 and 0.1% (w/v). Prenylated phenolic compounds were significantly (p<0.01) correlated with the antibacterial properties of the extracts. Furthermore, the position of the prenyl group within the phenolic skeleton also influenced the antibacterial activity. Overall, prenylated phenolics from legume seedlings can serve multiple purposes, e.g. as phytoestrogens they can provide health benefits and as natural antimicrobials they offer preservation of foods. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. The concept of ’Musa-pelo and the medicinal use of shrubby legumes (Fabaceae in Lesotho

    Directory of Open Access Journals (Sweden)

    A. Moteetee

    2007-08-01

    Full Text Available In the Kingdom of Lesotho, 20 plant species are commonly known as  'Musa-pelo. The term literally means ‘the one who brings back or tums around the heart’.  'Musa-pelo is traditionally used as a sedative and is given as a first aid treatment to bereaved people who are under severe psychological duress or stress. Of the 20 species known as  'Musa-pelo, 17 belong to nine genera of the Fabaceae  (Argyrolobium, Crotalaria, Indigofera, Lessertia, Lotononis, Melolobium, Sutherlandia, Tephrosia and  Trifolium. The three remaining species namely Cleome monophylla, Heliophila carnosa and  Cysticapnos pruinosa, belong to the families Capparaceae, Brassicaceae and Fumariaceae, respectively. In this paper, the concept of 'Musa-pelo in traditional medicine is explored.

  2. GERMINAÇÃO DE SEMENTES DE Platymiscium floribundum VOG. (FABACEAE SOB A INFLUÊNCIA DA LUZ E TEMPERATURAS

    Directory of Open Access Journals (Sweden)

    Magnólia Martins Alves

    2016-01-01

    Full Text Available ABSTRACT Platymiscium floribundum Vog., a forest species belonging to the family Fabaceae, has great potential for economic exploitation and can be used both in landscape and in reforestation, in the restoration of degraded areas and permanent preservation.given its importance, this work was, it was aimed to study the influence of light and temperature on seed germination of Platymiscium floribundum . We evaluate the germination and vigor Under constant and alternate temperatures of 25 and 30 0 C in different light regimes: White (LB, green (LV, red-far (LVD, red (LV and absence light (A. The experimental design was completely randomized in a factorial 3 x 5 with four replications of 25 seeds. The variables analyzed were: germination, first count of germination, germination speed index (IGV, length and seedling dry weight (root length, shoot length of seedlings. The seeds of Platymiscium floribundum express their maximum force in illuminated environment independent of the temperature.

  3. Caracterização farmacognóstica da espécie Erythrina falcata Benth., Fabaceae

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    Emanuel Eustáquio Almeida

    Full Text Available Erythrina falcata Benth., Fabaceae, conhecida popularmente no Brasil pelos nomes de mulungu, sapatinho-de-judeu, corticeira-da-serra, muchoco, é usada pela população como planta medicinal indicada como sedativo, ansiolítico ou para doenças do aparelho respiratório. Seu uso indiscriminado, no entanto, pode trazer consequências graves à saúde, devido à forte presença de alcaloides, particularmente nas sementes e na casca. O presente trabalho tem como objetivo estudos fitoquímicos para identificação dos principais grupos de substâncias existentes na espécie, além de estudos morfológicos e histológicos para diferenciação entre outras espécies do gênero.

  4. Tolerancia a la desecación de semillas de Prosopis ferox y Pterogyne nitens (Fabaceae

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    Marcelo Nahuel Morandini

    2013-03-01

    Full Text Available La elevada diversidad de especies y endemismos, conjuntamente con la acelerada pérdida de biodiversidad por deforestaciones, destaca la importancia de emprender acciones combinadas de conservación in situ y ex situ. El objetivo de este trabajo fue estudiar la tolerancia a la desecación de las semillas de Prosopis ferox y Pterogyne nitens, para su conservación ex situ a largo plazo en el BGEN. El contenido de humedad (CH se determinó colocando las semillas de cada población en estufa a 103°C y pesando las muestras a intervalos regulares hasta peso constante. Se realizaron ensayos de germinación en distintos CH: semillas frescas, 10-12%, 3-5%, y en semillas mantenidas seis meses a -20ºC y a 3-5% de CH. El CH de las semillas frescas de P. ferox fue de 14.2% y el de P. nitens de 10% para las dos poblaciones estudiadas. Las semillas de P. ferox llegaron a peso constante a las 17hr y las de P. nitens a las 3hr de secado. La germinación de las semillas de P. ferox fue mayor en los tratamientos con escarificación y la diferencia aumento con la reducción del CH y el almacenamiento. Las semillas de P. nitens con el CH reducido, requieren escarificación. Se concluye que las semillas de ambas especies son probablemente ortodoxas ya que la germinación superó el 80% en las semillas desecadas al 3-5% CH y almacenadas durante seis meses a -20°C.Desiccation tolerance in seeds of Prosopis ferox and Pterogyne nitens (Fabaceae. The high number of endemisms and species diversity together with the accelerated biodiversity loss by deforestation, especially in North Western Argentina, points out the need to work on species conservation combining ex situ and in situ strategies. The aim of this work was to study the desiccation tolerance in seeds of P. ferox and P. nitens for long term ex situ conservation at the Germplasm Bank of Native Species (BGEN of the National University of Salta (Argentina. The fruits were collected from ten individuals in P

  5. Anti-methicillin-resistant Staphylococcus aureus (MRSA) activity of Rubiaceae, Fabaceae and Poaceae plants: A search for new sources of useful alternative antibacterials against MRSA infections.

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    Sharifi-Rad, M; Iriti, M; Sharifi-Rad, M; Gibbons, S; Sharifi-Rad, J

    2016-08-29

    In this study, we evaluated the effects of the extracts of the leaves of species from the Rubiaceae (Galium aparine L. and Asperula arvensis L.), Fabaceae (Lathyrus aphaca L. and Vicia narbonensis L.) and Poaceae (Digitaria sanguinalis (L.) Scop. and Hordeum murinum L.) plant families on a wide and extensive panel of isolated methicillin-resistant Staphylococcus aureus strains (MRSA). The effects of the methanolic leaf extracts of Rubiaceae, Fabaceae and Poaceae plants on MRSA were evaluated by the disc diffusion assay and the broth dilution method. Among a total of 177 S. aureus isolates, 92 (51.97%) were found to be methicillin-resistant in an antibiogram and this was confirmed by the presence of the mecA gene in polymerase chain reaction method. All MRSA isolates were sensitive to all extracts. There were dose-dependent inhibitions on tested microorganisms for all plant extracts which showed maximum inhibition zones at a concentration of 300 mg/L. L. aphaca, G. aparine and H. murinum exhibited the highest antibacterial activity on the MRSA strains compared to the positive control (P Fabaceae), G. aparine (Rubiaceae), and H. murinum (Poaceae) proved to have high antibacterial activity on MRSA isolates, thus representing promising antimicrobial agents in clinical settings.

  6. Aves explorando flores de Erythrina fusca (Leguminosae, Fabaceae durante a estação seca no Pantanal de Mato Grosso Exploitation of Erythrina fusca (Leguminosae, Fabaceae flowers by birds during the dry season in Pantanal of Mato Grosso, Brazil

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    Ricardo Parrini

    2010-06-01

    Full Text Available Estudos recentes têm evidenciado a importância de flores como recurso alimentar de diversas espécies de aves neotropicais. Este estudo teve o objetivo de listar espécies e descrever o comportamento das aves que se alimentaram de recursos florais de Erythrina fusca (Fabaceae no Pantanal Mato-Grossense. Para isso, foram acompanhadas aves que se alimentaram em 14 árvores floridas dessa espécie em um total de cerca de 25 horas de observação. Como resultados, 20 espécies de aves pertencentes a sete famílias taxonômicas foram observadas alimentando-se de recursos florais de E. fusca. Apesar de várias espécies de aves terem apresentado comportamentos destrutivos em maior proporção, algumas espécies, sobretudo das famílias Trochilidae e Icteridae, apresentaram estratégias alimentares compatíveis com o transporte de pólen. O cruzamento dos dados obtidos neste estudo com os da literatura indicam que a família Icteridae pode ter relevante papel na polinização dessa espécie vegetal.Recent studies reported the importance of flowers in the diet of many Neotropical bird species. In this paper we identify and describe the feeding behaviour of bird species that feed on flower resources of Erythrina fusca (Fabaceae in the Pantanal Mato-Grossense, Brazil. We recorded birds foraging in 14 flowered individuals of E. fusca during 25 hours of observation. We recorded 20 bird species belonging to seven families feeding on the flowers. Several of the observed behaviours were destructive, despite some species, especially the Trochilidae and Icteridae, showed feeding strategies that preserve the integrity of the flowers and are compatible with pollen transportation. The comparison of the data gathered in this study with the available literature indicates that the Icteridae may play an important role in pollination of this tree species.

  7. A study of the fatty acid and tocochromanol patterns of some Fabaceae (Leguminosae plants from Turkey I

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    Sahim, Ahmet

    2004-12-01

    Full Text Available In this study, the fatty acid, tocopherol, tocotrienol and plastochromanol-8 contents of some selected Fabaceae (Leguminosae species belonging to different genera (Colutea, Vicia, Lathyrus, Gonocytisus, Lupinus, Hedysarum, Onobrychis, Trigonella from Turkey were determined by using GLC and HPLC techniques. Some of the studied species are endemic to Turkey. The seed oils of different Leguminous taxa contained linoleic, oleic and linolenic acids as their major components. The ratios of these fatty acids in the Leguminous genera were found to be highly variable. Palmitic and stearic acids are the major saturated fatty acids in the seed oils. Vicia and Onobrychis patterns showed high similarity in means of qualitative fatty acid concentration. The tocopherol and tocochromanol patterns of the seed oils were also found to be highly variable among the genera investigated here. The total tocopherols was higher than the total tocotrienols. Alpha and gamma tocopherols were also the highest tocopherols present in the whole species. Beta, gamma and delta-tocotrienols were not found in most of the studied leguminous patterns. The results are discussed in view of renewable sources and chemotaxonomy.En este estudio, los contenidos en ácidos grasos, tocoferoles, tocotrienoles y plastocromanol-8 de algunas especies seleccionadas de Fabaceae (Leguminosae, pertenecientes a diferentes géneros (Colutea, Vicia, Lathyrus, Gonocytisus, Lupinus, Hedysarum, Onobrychis, Trigonella de Turquía, fueron determinadas usando técnicas de GLC y HPLC. Algunas de las especies estudiadas son endémicas de Turquía. Los aceites de semillas de los diferentes taxones de leguminosas contenían los ácidos linoleico, oleico y linolénico como principales componentes. Las proporciones de estos ácidos grasos fueron muy variables entre los géneros de leguminosas. Los ácidos palmítico y esteárico son los principales ácidos grasos saturados en los aceites de semillas. Los patrones

  8. Antifeedant activity of botanical crude extracts and their fractions on Bemisia tabaci (Homoptera: Aleyrodidae adults: I. Gliricidia sepium (Fabaceae

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    Guillermo Flores

    2008-12-01

    Full Text Available Bemisia tabaci is an important virus vector on a number of crops worldwide. Therefore, a preventive approach to deal with viral epidemics may be the deployment of repellents or phagodeterrents at earlier stages of plant development (critical period. Thus, the crude extract and four fractions thereof (water, water:methanol, methanol, and diethyl ether of mother-of-cocoa (Gliricidia sepium, Fabaceae were tested for phagodeterrence to B. tabaci adults under greenhouse conditions, on tomato plants, in Costa Rica. Both restricted-choice and unrestricted-choice experiments showed that the crude extract and some fractions exerted such effect on the insect. In the former (in sleeve cages, three fractions caused deterrence at doses as low as 0.1% (methanol, 0.5% (water:methanol and 1.5% (diethyl ether. However, in the latter (plants exposed in a greenhouse no one of the fractions performed well, suggesting that the deterrent principles somehow decomposed under the experimental conditions. Rev. Biol. Trop. 56 (4: 2099-2113. Epub 2008 December 12.Mundialmente, Bemisia tabaci es un importante vector de virus en numerosos cultivos. Por tanto, un enfoque preventivo para enfrentar las epidemias virales podría ser el empleo de sustancias repelentes o fagodisuasivas en las etapas tempranas del desarrollo de las plantas (período crítico. Así, tanto el extracto crudo como cuatro fracciones (agua, agua:metanol, metanol y éter dietílico del madero negro (Gliricidia sepium, Fabaceae fueron evaluadas en cuanto a su actividad fagodisuasiva sobre los adultos de B. tabaci en condiciones de invernadero, utilizando plantas de tomate, en Turrialba, Costa Rica. Tanto los experimentos de escogencia restringida como los de escogencia irrestricta revelaron que el extracto crudo y algunas fracciones mostraron dicha actividad. En los primeros experimentos (en jaulas de manga, tres fracciones causaron fagodisuasión a dosis tan bajas como 0.1% (metanol, 0.5% (agua:metanol y

  9. Anatomía foliar y del pecíolo de cuatro especies de Lupinus (Fabaceae Foliar and petiole anatomy of four species of Lupinus (Fabaceae

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    Juan Francisco Zamora-Natera

    2012-09-01

    Full Text Available Se describe y compara la anatomía foliar y del pecíolo de 4 especies del género Lupinus (L. aschenbornii S.Schauer, L. exaltatus Zucc., L. montanus Kunth y L. reflexus Rose que se distribuyen en un gradiente altitudinal en el Parque Nacional Nevado de Colima. Las hojas se fijaron en campo y se procesaron mediante la técnica de inclusión en parafina. Parte de las láminas se deshidrataron para caracterizar la superficie foliar por medio del microscopio electrónico de barrido. Las especies comparten la epidermis papilosa de paredes anticlinales con diferentes grados de ondulación, estomas anomocíticos, tricomas simples lineares y mesofilo bifacial. Los folíolos de L. montanus son glabros en la superficie abaxial, las estrías cuticulares sobre las células localizadas en la base de los tricomas es un rasgo característico de L. montanus y de L. reflexus. Las diferencias encontradas en espesor de la lámina y del mesofilo así como la abundancia de ceras epicuticulares pueden estar influenciadas por el ambiente. Distintivamente, el número y distribución de haces vasculares en los pecíolos difieren entre las 4 especies y podrían ser de utilidad para diferenciarlas si estos resultados se confirman al estudiar un mayor número de especies de Lupinus.The aims of this study were to describe and compare the foliar and petiole anatomy of 4 species of Lupinus (L. aschenbornii S.Schauer, L. exaltatus Zucc., L. montanus Kunth, and L. reflexus Rose distributed in an elevation gradient at Parque Nacional Nevado de Colima. Leaves were fixed in the field and prepared using the paraffin embedding technique. In addition, part of the blades was dehydrated to describe leaf surface through the scanning electron microscope. The 4 species shared a papillose epidermis with undulated anticlinal walls in different degrees, stomata anomocytic, simple unicellular trichomes, and bifacial mesophyll. Leaflets of L. montanus are glabrous on the abaxial surface

  10. Geographical isolation caused the diversification of the Mediterranean thorny cushion-like Astragalus L. sect. Tragacantha DC. (Fabaceae).

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    Hardion, Laurent; Dumas, Pierre-Jean; Abdel-Samad, Farah; Bou Dagher Kharrat, Magda; Surina, Bostjan; Affre, Laurence; Médail, Frédéric; Bacchetta, Gianluigi; Baumel, Alex

    2016-04-01

    Understanding the origin and evolution of Mediterranean vascular flora within the long-term context of climate change requires a continuous study of historical biogeography supported by molecular phylogenetic approaches. Here we provide new insights into the fascinating but often overlooked diversification of Mediterranean xerophytic plants. Growing in some of the most stressing Mediterranean environments, i.e. coastal and mountainous opened habitats, the circum-Mediterranean Astragalus L. sect. Tragacantha DC. (Fabaceae) gathers several thorny cushion-like taxa. These have been the subjects of recent taxonomical studies, but they have not yet been investigated within a comprehensive molecular framework. Bayesian phylogenetics applied to rDNA ITS sequences reveal that the diversification of A. sect. Tragacantha has roots dating back to the Pliocene, and the same data also indicate an eastern-western split giving rise to the five main lineages that exist today. In addition, AFLP fingerprinting supports an old east-west pattern of vicariance that completely rules out the possibility of a recent eastern origin for western taxa. The observed network of genetic relationships implies that contrary to what is widely claimed in the taxonomic literature, it is range fragmentation, as opposed to a coastal-to-mountain ecological shift, that is likely the main driver of diversification. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Gelatinous fibers and variant secondary growth related to stem undulation and contraction in a monkey ladder vine, Bauhinia glabra (Fabaceae).

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    Fisher, Jack B; Blanco, Mario A

    2014-04-01

    Some of the most striking stem shapes occur in species of Bauhinia (Fabaceae) known as monkey ladder vines. Their mature stems are flattened and develop regular undulations. Although stems have variant (anomalous) secondary growth, the mechanism causing the undulations is unknown. We measured stem segments over time (20 mo), described stem development using light microscopy, and correlated the changes in stem shape with anatomy. Growing stems are initially straight and bear tendrils on short axillary branches. The inner secondary xylem has narrow vessels and lignified fibers. As stems age, they become flattened and increasingly undulated with the production of two lobes of outer secondary xylem (OX) with wide vessels and only gelatinous fibers (G-fibers). Similar G-fibers are present in the secondary phloem and the cortical sclerified layer. In transverse sections, the concave side of each undulation has a greater area and quantity of G-fibers than the opposite convex side. Some older stems are not undulated and have less lobing of OX. Undulation causes a shortening of the stem segments: up to 28% of the original length. Uneven distribution of G-fibers produces tensions that are involved in the protracted development of undulations. While young extending shoots attach by lateral branch tendrils, older stems may maintain their position in the canopy using undulations and persistent branch bases as gripping devices. Flattened and undulated stems with G-fibers produce flexible woody stems.

  12. An acyltransferase gene that putatively functions in anthocyanin modification was horizontally transferred from Fabaceae into the genus Cuscuta

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    Ting Sun

    2016-06-01

    Full Text Available Horizontal gene transfer (HGT refers to the flow of genetic materials to non-offspring, and occasionally HGT in plants can improve the adaptation of organisms in new niches due to expanded metabolic capability. Anthocyanins are an important group of water-soluble red, purple, or blue secondary metabolites, whose diversity results from modification after the main skeleton biosynthesis. Cuscuta is a stem holoparasitic genus, whose members form direct connection with hosts to withdraw water, nutrients, and macromolecules. Such intimate association is thought to increase the frequency of HGT. By transcriptome screening for foreign genes in Cuscuta australis, we discovered that one gene encoding a putative anthocyanin acyltransferase gene of the BAHD family, which is likely to be involved in anthocyanin modification, was acquired by C. australis from Fabaceae through HGT. The anthocyanin acyltransferase-like (AT-like gene was confirmed to be present in the genome assembly of C. australis and the transcriptomes of Cuscuta pentagona. The higher transcriptional level in old stems is consistent with its putative function in secondary metabolism by stabilizing anthocyanin at neutral pH and thus HGT of this AT-like gene may have improved biotic and abiotic resistance of Cuscuta.

  13. Effects of the hydroethanolic extract of Mucuna pruriens (L.) DC (Fabaceae) on haematological profile in normal and haloperidol treated rats.

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    Akindele, Abidemi J; Busayo, Fadeyibi I

    2011-01-01

    Mucuna pruriens (L.) DC (Fabaceae) is a climbing plant claimed in traditional medicine to possess anti-anaemic effect. The study is to investigate the effects of the hydroethanolic extract of M. pruriens (MP) on haematological profile in normal and haloperidol treated rats. MP was administered p.o. at doses of 50, 100, 200, and 400 mg/kg to groups of rats daily for 28 days. Control animals received distilled water. Rats were sacrificed on the 28th day and blood samples collected for evaluation of haematological parameters and serum iron. Another set of animals received MP p.o. at same doses but along with haloperidol (0.2 mg/kg, i.p.) daily for 4 days. Three other groups of rats received distilled water, haloperidol, and MP at 400 mg/kg alone. Haematological parameters and serum iron were determined. Extract iron content, phytochemical analysis and acute toxicity studies were also carried out. MP administered to normal rats for 28 days significantly (p Mucuna pruriens possibly possess beneficial effects in anaemic conditions especially associated with iron deficiency.

  14. EVALUATION OF DIFFERENT PRE-GERMINATIVE METHODS FOR THREE TREE SPECIES OF THE FABACEAE FAMILY IN DIFFERENT ENVIRONMENTS

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    R N Costa

    2018-02-01

    Full Text Available The Sesbania virgata (Cav. Pers., Mimosa caesalpiniifolia Benth. and Cassia grandis L.f. species belong to the Fabaceae family, are characterized by their seeds present a dormant state, which limits the germination. The aim of this study was to evaluate the efficiency of pre-germination treatments to overcome dormancy these species. Seeds were collected from matrix trees, located in Agreste of Alagoas and the research developed at the Federal University of Alagoas – Campus de Arapiraca. Overcoming of dormancy was studied in laboratory and greenhouse, where they were employed eight treatments with four replications of 25 seeds, in a completely randomized design: immersion in sulfuric acid (in three periods of immersion, depending on species, scarification with sandpaper, immersion in hot water at 80 °C (2.5 and 5 minutes, imbibition for 24 hours in distilled water and control (seeds without the application of any treatment. The evaluation of the results was made through of germination and emergence percentage; germination and emergence speed index and germination and emergence average time. The pre-germination treatments, mechanical scarification with sandpaper and chemical scarification with sulfuric acid in different immersion times were the most efficient to overcome the seeds dormancy of Sesbania virgata, Mimosa caesalpiniifolia and Cassia grandis Independent of the studied environments.

  15. Aspectos étnicos, biológicos e químicos de Senna occidentalis (Fabaceae

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    T. M. KANEKO

    2009-08-01

    Full Text Available Senna occidentalis (sin. Cassia occidentalis é um arbusto perene nativo da América do Sul e distribuída em regiões tropicais ao redor do mundo, frequentemente contaminando pastos e culturas de cereais. Inúmeros estudos demonstraram que esta planta é tóxica para animais. Na medicina popular, tribos americanas, africanas e indianas usam preparações da S. occidentalis como tônico, estomáquico, febrífugo, laxante e antimicrobiano. Diversas propriedades biológicas da espécie já foram comprovadas, tais como a antibacteriana, antifúngica, antimalárica, antitumoral e hepatoprotetora. As análises fitoquímicas evidenciaram que as antraquinonas, os flavonóides e outros derivados fenólicos são os seus principais constituintes. Esta revisão apresenta dados etnofarmacológicos, químicos e biológicos publicados na literatura sobre S. occidentalis. Palavras-chave: Senna occidentalis. Cassia occidentalis. Fabaceae. Leguminosae. Caesalpinioideae. Fedegoso.

  16. Transferencia de algunos marcadores moleculares microsatélites de la familia Fabaceae en tarwi (Lupinus mutabilis Sweet

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    Michelle C. Chirinos-Arias

    2015-01-01

    Full Text Available Con el objetivo de analizar la transferencia de 15 iniciadores microsatélites de la familia Fabaceae en Lupinus mutabilis Sweet “tarwi”, escogidos por presentar transferibilidad entre especies y géneros, por su alto índice de contenido polimórfico (PIC y alto grado de heterocigosidad observada y esperada. Se extrajo el ADN de 300 plantas de tarwi, se estandarizaron las condiciones PCR haciendo gradientes de los diferentes componentes del master mix. Para el screening se corrieron los iniciadores en gel de agarosa 3% con algunas muestras. Finalmente se amplificó la población y se corrieron en gel de poliacrilamida 6% por su mayor resolución. Sólo el 6,67% de iniciadores amplificaron pero resultaron ser monomórficos, por lo que no pueden usarse en caracterización molecular. Se propone ocho iniciadores microsatélites para tarwi, los cuales deben ser probados en condiciones de laboratorio.

  17. Distribution of the endophytic fungi community in leaves of Bauhinia brevipes (Fabaceae Distribuição da comunidade de fungos endofíticos em folhas de Bauhinia brevipes (Fabaceae

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    Mariana Patrícia Amorim Hilarino

    2011-12-01

    Full Text Available Endophytic fungi represent large, yet unexplored components of biodiversity. This work evaluated the richness and the distribution of endophytes in the leaves of Bauhinia brevipes (Fabaceae. A total of 1110 colonies were recovered from the samples and grouped by their morphological traits into 126 taxa. The total number of taxa according to leaf development was: 102 in mature leaves, 93 in recently expanded leaves and 79 for unfolded leaves. The major endophyte genera were Phomopsis, followed by Dothiorella, Pestalotiopsis and Acremonium. The richness and the isolate numbers of endophytes were not statistically affected by leaf region. However, some taxa were leaf-age specific; six were isolated only from unfolded leaves, nine from recently expanded leaves and 17 were exclusively found in mature leaves. The composition of endophytes varied with leaf region; the similarities (Jaccard's Index among the leaf regions of different leaf ages ranged from 0.36 to 0.46, indicating a high spatial variation in the community of endophytic fungi inside the leaves. The high richness of endophytes in this host plant highlights a significant contribution of fungi to tropical biodiversity and the need for further research in this area.Fungos endofíticos representam um grande e ainda pouco explorado componente da biodiversidade. O trabalho avaliou a riqueza e a distribuição endofítica nas folhas de Bauhinia brevipes (Fabaceae. Foram obtidas 1110 colônias que foram agrupadas, por suas características morfológicas em 126 táxons. O número total de táxons por estágio foliar foi: 102 em folhas maduras, 93 em folhas recém-expandidas e 79 em não expandidas. O principal gênero de endofítico encontrado foi Phomopsis, seguido por Dothiorella, Pestalotiopsis e Acremonium. A riqueza e o número de isolados não foram estatisticamente influenciadas pela região foliar. Contudo, alguns táxons foram específicas de um estágio foliar; seis foram isoladas apenas

  18. Chrysoperla externa (Neuroptera: Chrysopidae and Utetheisa ornatrix (Lepidoptera: Arctiidae on organically grown Crotalaria juncea (Fabaceae Chrysoperla externa (Neuroptera: Chrysopidae e Utetheisa ornatrix (Lepidoptera: Arctiidae sobre Crotalaria juncea (Fabaceae cultivada organicamente

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    M.A. Costa

    2012-09-01

    Full Text Available Chrysoperla externa (Neuroptera: Chrysopidae larvae can avoid foraging on plants of Crotalaria juncea (Fabaceae after the issuance of floral buds, when the prey of Utetheisa ornatrix (Lepidoptera: Arctiidae incorporate toxic pyrrolizidine alkaloids from this plant. This reduces the predation and favors increasing the number of adults and eggs of this defoliator on crops of this plant. The aim of the present paper was to evaluate some biological and ecological aspects of C. externa and U. ornatrix on the organic crop of C. juncea in the EMBRAPA Maize and Sorghum in Sete Lagoas, Minas Gerais State, Brazil. Chrysoperla externa and U. ornatrix were more abundant in the vegetative and flowering stages of C. juncea, respectively, with caterpillars of this defoliator feeding on leaves and seeds of this plant. The duration of the stages/instars, survival, lifetime fecundity, and oviposition showed that the branches of C. juncea are a suitable food for U. ornatrix. The abundance of adults and larvae of C. externa was lower in the flowering and pods stages of C. juncea, respectively, when the postures of U. ornatrix are present, probably due to the toxicity of the eggs of this prey to this predator. During these stages, C. externa may be reared with alternative hosts, and when the crops of C. juncea are scarce, an artificial diet should be used for rearing this defoliator in the laboratory for biological research and the development of biological control tactics.Larvas de Chrysoperla externa (Neuroptera: Chrysopidae podem evitar o forrageamento sobre plantas de Crotalaria juncea (Fabaceae após a emissão de botões florais, quando presas de Utetheisa ornatrix (Lepidoptera: Arctiidae incorporam alcalóides pirrolizidínicos tóxicos dessa planta. Isso reduz a predação e favorece o aumento do número de adultos e ovos desse desfolhador sobre cultivos dessa planta. O objetivo deste trabalho foi avaliar alguns aspectos biológicos e ecológicos de C

  19. Impact of a gall midge Parkiamyia paraensis (Diptera, Cecidomyiidae on the Amazonian plant Parkia pendula (Fabaceae Impacto do galhador Parkiamyia paraensis (Diptera, Cecidomyiidae sobre a planta da Amazônia Parkia pendula Benth. ex Walp. (Fabaceae

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    G. Wilson Fernandes

    2007-12-01

    Full Text Available We observed the occurrence of large numbers of galls induced by Parkiamyia paraensis (Diptera, Cecidomyiidae on the leaflets of Parkia pendula (Fabaceae in northern Para, Brazil. We addressed two questions in this study: i what is the proportion of attacked plants in the field, and nursery conditions?; and ii what is the impact of galls on the host plant? An average of 86% of the plants were galled in the field. Galled P. pendula were distinct from healthy individuals due to their prostrated architecture and death of terminal shoots. Approximately 50% of the total available leaves and 35% leaflets were attacked by P. paraensis on saplings under nursery conditions. Each one-year old plant supported an average of 1,300 galls, and an average of 60g allocated to galled tissue. Otherwise, attacked individuals were taller and heavier than healthy plants. Attacked plants weighed five times more than healthy plants. When the weight of the galls was removed, the total weight (aerial part without galls of attacked plants was drastically reduced, indicating that most of the biomass of attacked plants was due to the attack by P. paraensis galls. Although the data indicate a paradox, as young plants attacked by the galling herbivore appear to develop more vigorously than unattacked plants, we suggest that P. paraensis negatively affect P. pendula development.Observou-se a ocorrência de um grande número de galhas induzidas por Parkiamyia paraensis (Diptera, Cecidomyiidae nos folíolos de Parkia pendula (Fabaceae no norte do Pará, Brasil. Este estudo foi direcionado para responder duas perguntas: i qual é a proporção de plantas atacadas no campo e em condições de estufa? e ii qual é o impacto das galhas na planta hospedeira? Uma média de 86% das plantas apresentaram galhas no campo. Indivíduos com galhas de P. pendula eram distintos dos indivíduos saudáveis devido à arquitetura curvada e pela morte dos ramos terminais. Aproximadamente 50% do

  20. Discovery and Characterization of Novel Cyclotides Originated from Chimeric Precursors Consisting of Albumin-1 Chain a and Cyclotide Domains in the Fabaceae Family*

    Science.gov (United States)

    Nguyen, Giang Kien Truc; Zhang, Sen; Nguyen, Ngan Thi Kim; Nguyen, Phuong Quoc Thuc; Chiu, Ming Sheau; Hardjojo, Antony; Tam, James P.

    2011-01-01

    The tropical plant Clitoria ternatea is a member of the Fabaceae family well known for its medicinal values. Heat extraction of C. ternatea revealed that the bioactive fractions contained heat-stable cysteine-rich peptides (CRPs). The CRP family of A1b (Albumin-1 chain b/leginsulins), which is a linear cystine knot CRP, has been shown to present abundantly in the Fabaceae. In contrast, the cyclotide family, which also belongs to the cystine knot CRPs but with a cyclic structure, is commonly found in the Rubiaceae, Violaceae, and Cucurbitaceae families. In this study, we report the discovery of a panel of 15 heat-stable CRPs, of which 12 sequences (cliotide T1–T12) are novel. We show unambiguously that the cliotides are cyclotides and not A1bs, as determined by their sequence homology, disulfide connectivity, and membrane active properties indicated by their antimicrobial activities against Escherichia coli and cytotoxicities to HeLa cells. We also show that cliotides are prevalent in C. ternatea and are found in every plant tissue examined, including flowers, seeds, and nodules. In addition, we demonstrate that their precursors are chimeras, half from cyclotide and the other half from Albumin-1, with the cyclotide domain displacing the A1b domain in the precursor. Their chimeric structures likely originate from either horizontal gene transfer or convergent evolution in plant nuclear genomes, which are exceedingly rare events. Such atypical genetic arrangement also implies a different mechanism of biosynthetic processing of cyclotides in the Fabaceae and provides new understanding of their evolution in plants. PMID:21596752

  1. Importance of nickel in Fabaceae. Pt. 1. Comparative studies on the content of nickel and certain other elements in vegetative parts and seeds

    Energy Technology Data Exchange (ETDEWEB)

    Horak, O

    1985-02-28

    Vegetative parts and seeds of 15 Fabaceae were analyzed with respect to concentrations of Ni as well as K, Ca, Mg, Fe, Mn, Zn, Cu and Mo. The distribution pattern of the examined elements is different. For the macronutrients and iron mostly a significant higher concentration could be found in the shoot, whilst micronutrients frequently were accumulated in the seed. Nickel is that element, which is accumulated relatively highest in the seed. This is a criterion for a specific importance of nickel, which is a compound of urease and in this function could be involved in the mobilization of nitrogen storage substances of the seed.

  2. Phylogeny, biogeography and character evolution in the tribe Desmodieae (Fabaceae: Papilionoideae), with special emphasis on the New Caledonian endemic genera.

    Science.gov (United States)

    Jabbour, Florian; Gaudeul, Myriam; Lambourdière, Josie; Ramstein, Guillaume; Hassanin, Alexandre; Labat, Jean-Noël; Sarthou, Corinne

    2018-01-01

    The nearly cosmopolitan tribe Desmodieae (Fabaceae) includes many important genera for medicine and forage. However, the phylogenetic relationships among the infratribal groups circumscribed using morphological traits are still poorly known. In this study, we used chloroplast (rbcL, psbA-trnH) and nuclear (ITS-1) DNA sequences to investigate the molecular phylogeny and historical biogeography of Desmodieae, and infer ancestral states for several vegetative and reproductive traits. Three groups, corresponding to the Desmodium, Lespedeza, and Phyllodium groups sensu Ohashi were retrieved in the phylogenetic analyses. Conflicts in the topologies inferred from the chloroplast and nuclear datasets were detected. For instance, the Lespedeza clade was sister to the groups Phyllodium+Desmodium based on chloroplast DNA, but nested within the Desmodium group based on ITS-1. Moreover, the New Caledonian endemic genera Arthroclianthus and Nephrodesmus were not monophyletic but together formed a clade, which also included Hanslia and Ohwia based on chloroplast DNA. The hypothetical common ancestor of Desmodieae was dated to the Middle Oligocene (ca. 28.3Ma) and was likely an Asian shrub or tree producing indehiscent loments. Several colonization events towards Oceania, America, and Africa occurred (all less than ca. 17.5Ma), most probably through long distance dispersal. The fruits of Desmodieae repeatedly evolved from indehiscence to dehiscence. We also showed that indehiscent loments allow for more variability in the number of seeds per fruit than indehiscent legumes. Modularity seems here to allow variability in the number of ovules produced in a single ovary. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Seed colour affects light and temperature requirements during germination in two Lotus species (Fabaceae) of the Arabian subtropical deserts.

    Science.gov (United States)

    Bhatt, Arvind; Gairola, Sanjay; El-Keblawy, Ali A

    2016-06-01

    Heterogeneity in seeds mostly occurs due to physiological, environmental and genetic factors, and these could affect seed dormancy and germination. Therefore, the aim of our study was to assess the effect of seed colour on germination behavior. For this, both light and temperature requirements were assessed in Lotus glinoides and Lotus halophilus (Fabaceae) from the hyper-arid deserts of the United Arab Emirates. Germination was assessed in terms of both final germination level (percentage) and germination rate, as expressed by Timson’s germination velocity index. Lotus glinoides produces black and yellow-colored seeds, and L. halophilus produces green and yellow seeds. Different seed lots were germinated in both light and darkness at different temperatures. Yellow seeds of the two species attained significantly lower germination, compared to black and green seeds. There was no specific light or temperature requirements for the germination of the two coloured seeds of L. glinoides; the effect of interactions between seed colour and both light and incubation temperature, were not significant on the final germination percentage. In L. halophilus, green seeds germinated significantly more in both light and darkness at lower temperatures (15/25 °C) and in light at higher temperatures (25/35 °C), compared to yellow seeds. Yellow seeds germinated faster, compared to black at 15/25 °C in L. glinoides and compared to green seeds at 15/25 °C and 25/35 °C in L. halophilus. Seed colour variation, at least in L. halophilus, could be a survival strategy that would determine the time of germination throughout the year in the unpredictable desert environment.

  4. Lack of divergence in seed ecology of two Amphicarpaea (Fabaceae) species disjunct between eastern Asia and eastern North America.

    Science.gov (United States)

    Zhang, Keliang; Baskin, Jerry M; Baskin, Carol C; Yang, Xuejun; Huang, Zhenying

    2015-06-01

    Many congeneric species are disjunct between eastern Asia and eastern North America. No previous study has compared the seed biology of closely related disjunct taxa of legumes or of a diaspore-heteromorphic species. Our objective was to compare seed dormancy in two such sister species in the genus Amphicarpaea (Fabaceae). We investigated the ecology and ecophysiology of aerial and subterranean seeds of the amphicarpic species Amphicarpaea edgeworthii from China and compared the results to those published for its sister species A. bracteata from eastern North America. The seed coat of aerial seeds of A. edgeworthii is well developed, whereas the seed coat of subterranean seeds is not. Aerial seeds have combinational dormancy (physical dormancy [PY] + physiological dormancy [PD]) broken by scarification followed by cold stratification or by after-ripening and scarification; whereas subterranean seeds have PD broken by cold stratification. Aerial seeds formed a persistent soil seed bank, and subterranean seeds a transient soil seed bank. Aerial seeds of A. bracteata also have PY+PD and subterranean seeds PD. Subterranean seeds of both species are desiccation intolerant. Dormancy in neither aerial nor subterranean seeds of both species has diverged over geological time. Compared to subterranean seeds, aerial seeds of both species dispersed over longer distances. Seed dispersal ability and degree of dormancy of neither species fits the high-risk/low-risk (H-H/L-L) strategy found in many diaspore-dimorphic species. Rather, both species have an H-L/L-H strategy for these two life history traits. © 2015 Botanical Society of America, Inc.

  5. Population Genetic Structure of Glycyrrhiza inflata B. (Fabaceae) Is Shaped by Habitat Fragmentation, Water Resources and Biological Characteristics.

    Science.gov (United States)

    Yang, Lulu; Chen, Jianjun; Hu, Weiming; Yang, Tianshun; Zhang, Yanjun; Yukiyoshi, Tamura; Zhou, Yanyang; Wang, Ying

    2016-01-01

    Habitat fragmentation, water resources and biological characteristics are important factors that shape the genetic structure and geographical distribution of desert plants. Analysis of the relationships between these factors and population genetic variation should help to determine the evolutionary potential and conservation strategies for genetic resources for desert plant populations. As a traditional Chinese herb, Glycyrrhiza inflata B. (Fabaceae) is restricted to the fragmented desert habitat in China and has undergone a dramatic decline due to long-term over-excavation. Determining the genetic structure of the G. inflata population and identifying a core collection could help with the development of strategies to conserve this species. We investigated the genetic variation of 25 G. inflata populations based on microsatellite markers. A high level of population genetic divergence (FST = 0.257), population bottlenecks, reduced gene flow and moderate genetic variation (HE = 0.383) were detected. The genetic distances between the populations significantly correlated with the geographical distances, and this suggests that habitat fragmentation has driven a special genetic structure of G. inflata in China through isolation by distance. STRUCTURE analysis showed that G. inflata populations were structured into three clusters and that the populations belonged to multiple water systems, which suggests that water resources were related to the genetic structure of G. inflata. In addition, the biological characteristics of the perennial species G. inflata, such as its long-lived seeds, asexual reproduction, and oasis ecology, may be related to its resistance to habitat fragmentation. A core collection of G. inflata, that included 57 accessions was further identified, which captured the main allelic diversity of G. inflata. Recent habitat fragmentation has accelerated genetic divergence. The population genetic structure of G. inflata has been shaped by habitat

  6. Phylogeography of the Tree Hymenaea stigonocarpa (Fabaceae: Caesalpinioideae) and the Influence of Quaternary Climate Changes in the Brazilian Cerrado

    Science.gov (United States)

    Ramos, Ana Carolina Simões; Lemos-Filho, José Pires; Ribeiro, Renata Acácio; Santos, Fabrício Rodrigues; Lovato, Maria Bernadete

    2007-01-01

    Background and Aims Hymenaea stigonocarpa (Fabaceae: Caesalpinioideae) is an endemic tree from the Brazilian cerrado (savanna vegetation), a biome classified as a hotspot for conservation priority. This study investigates the phylogeographic structure of H. stigonocarpa, in order to understand the processes that have led to its current spatial genetic pattern. Methods The polymorphism level and spatial distribution of variants of the plastid non-coding region between the genes psbC and trnS were investigated in 175 individuals from 17 populations, covering the greater part of the total distribution of the species. Molecular diversity indices were calculated and intra-specific relationships were inferred by the construction of haplotype networks using the median-joining method. Genetic differentiation among populations and main geographical groups was evaluated using spatial analysis of molecular variance (SAMOVA). Key Results Twenty-three different haplotypes were identified. The level of differentiation among the populations analysed was relatively high (FST = 0·692). Phylogeographic analyses showed a clear association between the haplotype network and geographic distribution of populations, revealing three main geographical groups: western, central and eastern. SAMOVA corroborated this finding, indicating that most of the variation can be attributed to differences among these three groups (58·8 %), with little difference among populations within groups (FSC = 0·252). Conclusions The subdivision of the geographic distribution of H. stigonocarpa populations into three genetically differentiated groups can be associated with Quaternary climatic changes. The data suggest that during glacial times H. stigonocarpa populations became extinct in most parts of the southern present-day cerrado area. Milder climatic conditions in the north and eastern portions of the cerrado resulted in maintenance of populations in these regions. Thus it is inferred that the most

  7. Density dependent interactions between VA mycorrhizal fungi and even-aged seedlings of two perennial Fabaceae species.

    Science.gov (United States)

    Allsopp, N; Stock, W D

    1992-08-01

    The interaction of density and mycorrhizal effects on the growth, mineral nutrition and size distribution of seedlings of two perennial members of the Fabaceae was investigated in pot culture. Seedlings of Otholobium hirtum and Aspalathus linearis were grown at densities of 1, 4, 8 and 16 plants per 13-cm pot with or without vesicular-arbuscular (VA) mycorrhizal inoculum for 120 days. Plant mass, relative growth rates, height and leaf number all decreased with increasing plant density. This was ascribed to the decreasing availability of phosphorus per plant as density increased. O. hirtum was highly dependent on mycorrhizas for P uptake but both mycorrhizal and non-mycorrhizal A. linearis seedlings were able to extract soil P with equal ease. Plant size distribution as measured by the coefficient of variation (CV) of shoot mass was greater at higher densities. CVs of mycorrhizal O. hirtum plants were higher than those of non-mycorrhizal plants. CVs of the facultatively mycorrhizal A. linearis were similar for both mycorrhizal and non-mycorrhizal plants. Higher CVs are attributed to resource preemption by larger individuals. Individuals in populations with high CVs will probably survive stress which would result in the extinction of populations with low CVs. Mass of mycorrhizal plants of both species decreased more rapidly with increasing density than did non-mycorrhizal plant mass. It is concluded that the cost of being mycorrhizal increases as plant density increases, while the benefit decreases. The results suggest that mycorrhizas will influence density-dependent population processes of faculative and obligate mycorrhizal species.

  8. Current Status of the Systematics of Astragalus L. (Fabaceae with Special Reference to the Himalayan Species in India

    Directory of Open Access Journals (Sweden)

    Lal Babu Chaudhary

    2008-12-01

    Full Text Available Astragalus is considered one of the most diverse genera in the family Leguminosae (nom. alt. Fabaceae. Although a large number of works have been carried out on the genus, no monograph is available except some regional accounts and revisions chiefly at sectional level. It may be due to the sheer size of the genus (ca. 3000 spp. and diverse nature, the genus is quite variable in habit and habitats, size of the plants, nature of indumentums, stipules, leaf rachis, types of inflorescence, relative length of petals, pods etc. Usually, genus is divided into eight to ten subgenera and more than 245 sections. In recently conducted molecular phylogenetic studies it has been shown that none of the subgenera and large sections are monophyletic. However, it has been clearly demonstrated that Astragalus is monophyletic except some outlier species. The chromosome numbers are also quite interesting and significant in Astragalus for its phylogenetic studies. There is a strong correlation between its geographic distribution and chromosome numbers. Currently about 80 species have been recorded from India chiefly from the Himalayas. Except some of our recent publications, not much studies have been carried out on the genus in India after 'The Flora of British India'. Astragalus is not of much economic importance, however, some of its species are well known for commercial gum tragacanth production especially in Iran and China. In India, A. candolleanus is a well known drug as ‘Rudanti’ or ‘Rudravanti’used for tuberculosis, skin diseases, coughs and blood purifier. The aim of this article is to review the entire work carried out on Astragalus and to bring out scattered information at one place for better understanding of the subject and to find out the future prospective of the research in India on the genus.

  9. Tolerância à inundação: aspectos da anatomia ecológica e do desenvolvimento de Sesbania virgata (Cav. Pers. (Fabaceae

    Directory of Open Access Journals (Sweden)

    Viviane M. Davanso-Fabro

    1998-08-01

    Full Text Available Plantas de Sebania virgata (Cav. Pers. (Fabaceae cultivadas em casa de vegetação foram alagadas por 40 dias. Plantas alagadas apresentaram aumento do peso da matéria seca e comprimento, acentuadas rachaduras corticais e intumescimento cortical esponjoso em caules e raízes, raízes superficiais e raízes adventícias. É possível que a plasticidade morfo-anatômica apresentada por esta espécie esteja contribuindo para o seu estabelecimento em solos hipóxicos.Twenty days seedlings of Sesbania virgata (Cav. Pers. (Fabaceae cultivated in green house were flooded by forty days. Flooded plants presented increasing of dry weight and lenght, evident cortical fissures and spongy cortical swelling on the stem basis and root, superficial roots on the soil and adventitious roots. It is possible that the morpho-anatomic plasticity presented by this specie is contribuiting for its hipoxic soils stablishment.

  10. Alkaloid profile, antibacterial and allelopathic activities of Lupinus jaimehintoniana B.L. Turner (Fabaceae

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    Ruiz-González Nancy

    2012-01-01

    Full Text Available Herein we describe some aspects of the ethnobotanical use and the first alkaloid profile of Lupinus jaimehintoniana, the 5 to 8 m high arboreous lupine. Five quinolizidine alkaloids identified as sparteine, 5,6-dehydrolupanine, lupanine, nuttalline, and d-thermopsine, were characterized by the respective elution order according to their electronic impact spectra, lupanine being the most abundant in the four different tissues analyzed. Simultaneously, an antibacterial assessment of the four corresponding crude methanolic extracts, as well as the four semi-purified alkaloids was performed on specific Escherichia coli and Agrobacterium tumefaciens strains. These experiments resulted in MIC ranges of 37-61 µg mL-1 and 130-146 µg mL-1, respectively. for both bacterial species. Finally, the allelopathic activity of these extracts on the germination of Lactuca sativa seeds was demonstrated to be in the range of 50-300 µg mL-1 for both semi-purified alkaloid and methanolic extracts.

  11. Anatomical, biochemical, and photosynthetic responses to recent allopolyploidy in Glycine dolichocarpa (Fabaceae).

    Science.gov (United States)

    Coate, Jeremy E; Luciano, Amelia K; Seralathan, Vasu; Minchew, Kevin J; Owens, Tom G; Doyle, Jeff J

    2012-01-01

    Previous studies have shown that polyploidy has pronounced effects on photosynthesis. Most of these studies have focused on synthetic or recently formed autopolyploids, and comparatively little is known about the integrated effects of natural allopolyploidy, which involves hybridity and genome doubling and often incorporates multiple genotypes through recurrent origins and lineage recombination. Glycine dolichocarpa (designated T2) is a natural allotetraploid with multiple origins. We quantified 21 anatomical, biochemical, and physiological phenotypes relating to photosynthesis in T2 and its diploid progenitors, G. tomentella (D3) and G. syndetika (D4). To assess how direction of cross affects these phenotypes, we included three T2 accessions having D3-like plastids (T2(D3)) and two accessions having D4-like plastids (T2(D4)). T2 accessions were transgressive (more extreme than any diploid accession) for 17 of 21 phenotypes, and species means differed significantly in T2 vs. both progenitors for four of 21 phenotypes (higher for guard cell length, electron transport capacity [J(max)] per palisade cell, and J(max) per mesophyll cell; lower for palisade cells per unit leaf area). Within T2, four of 21 parameters differed significantly between T2(D3) and T2(D4) (palisade cell volume; chloroplast number and volume per unit leaf area; and J(max) per unit leaf area). T2 is characterized by transgressive photosynthesis-related phenotypes (including an ca. 2-fold increase in J(max) per cell), as well as by significant intraspecies variation correlating with plastid type. These data indicate prominent roles for both nucleotypic effects and cytoplasmic factors in photosynthetic responses to allopolyploidy.

  12. Morpho-anatomy, imbibition, viability and germination of the seed of Anadenanthera colubrina var. cebil (Fabaceae).

    Science.gov (United States)

    Varela, Rodolfo Omar; Albornoz, Patricia Liliana

    2013-09-01

    Seed biology is a relevant aspect of tropical forests because it is central to the understanding of processes of plant establishment, succession and natural regeneration. Anadenanthera colubrina var. cebil is a timber tree from South America that produces large seeds with thin weak teguments, which is uncommon among legumes. This study describes the morphology and anatomy of the seed coat, the viability, imbibition, and germination in this species. Seeds used during the essays came from 10 trees that grow naturally in Horco Molle, province of Tucumán, Argentina. Seed morphology was described from a sample of 20 units. The seed coat surface was examined with a scanning electron microscope. Transverse sections of hydrated and non-hydrated seeds were employed to describe the histological structure of the seed coat. Hydration, viability and germination experiments were performed under laboratory controlled conditions; and the experimental design consisted of 10 replicas of 10 seeds each. Viability and germination tests were conducted using freshly fallen seeds and seeds stored for five months. Morphologically the seeds of A. colubrina var. cebil are circular to subcircular, laterally compressed, smooth, bright brown and have a horseshoe fissure line (= pleurogram) on both sides. The seed coat comprises five tissue layers and a double (external and internal) cuticle. The outer cuticle (on the epidermis) is smooth and interrupted by microcracks and pores of variable depth. The epidermis consists of macroesclereids with non-lignified secondary walls. This layer is separated from the underlying ones during seed hydration. The other layers of internal tissues are comprised of osteosclereids, parenchyma, osteosclereids, and macrosclereids. The percentage of viable seeds was 93%, decreasing to 75% in seeds with five months old. Seed mass increased 76% after the first eight hours of hydration. Germination percentage was 75% after 76 hours. Germination of seeds stored for five

  13. Aberration of mitosis by hexavalent chromium in some Fabaceae members is mediated by species-specific microtubule disruption.

    Science.gov (United States)

    Eleftheriou, Eleftherios P; Michalopoulou, Vasiliki A; Adamakis, Ioannis-Dimosthenis S

    2015-05-01

    Because the detrimental effects of chromium (Cr) to higher plants have been poorly investigated, the present study was undertaken to verify the toxic attributes of hexavalent chromium [Cr(VI)] to plant mitotic microtubules (MTs), to determine any differential disruption of MTs during mitosis of taxonomically related species and to clarify the relationship between the visualized chromosomal aberrations and the Cr(VI)-induced MT disturbance. For this purpose, 5-day-old uniform seedlings of Vicia faba, Pisum sativum, Vigna sinensis and Vigna angularis, all belonging to the Fabaceae family, were exposed to 250 μM Cr(VI) supplied as potassium dichromate (K₂Cr₂O₇) for 24, 72 and 120 h and others in distilled water serving as controls. Root tip samples were processed for tubulin immunolabelling (for MT visualization) and DNA fluorescent staining (for chromosomal visualization). Microscopic preparations of cell squashes were then examined and photographed by confocal laser scanning microscopy (CLSM). Cr(VI) halted seedling growth turning roots brown and necrotic. Severe chromosomal abnormalities and differential disturbance of the corresponding MT arrays were found in all mitotic phases. In particular, in V. faba MTs were primarily depolymerized and replaced by atypical tubulin conformations, whereas in P. sativum, V. sinensis and V. angularis they became bundled in a time-dependent manner. In P. sativum, the effects were milder compared to those of the other species, but in all cases MT disturbance adversely affected the proper aggregation of chromosomes on the metaphase plate, their segregation at anaphase and organization of the new nuclei at telophase. Cr(VI) is very toxic to seedling growth. The particular effect depends on the exact stage the cell is found at the time of Cr(VI) entrance and is species-specific. Mitotic MT arrays are differentially deranged by Cr(VI) in the different species examined, even if they are taxonomically related, while their

  14. The inhibitory potential of the condensed-tannin-rich fraction of Plathymenia reticulata Benth. (Fabaceae) against Bothrops atrox envenomation.

    Science.gov (United States)

    de Moura, Valéria Mourão; da Silva, Wania Cristina Rodrigues; Raposo, Juliana D A; Freitas-de-Sousa, Luciana A; Dos-Santos, Maria Cristina; de Oliveira, Ricardo Bezerra; Veras Mourão, Rosa Helena

    2016-05-13

    Ethnobotanical studies have shown that Plathymenia reticulata Benth. (Fabaceae) has been widely used in cases of snake envenomation, particularly in Northern Brazil. In light of this, the aim of this study was to evaluate the inhibitory potential of the condensed-tannin-rich fraction obtained from the bark of P. reticulata against the main biological activities induced by Bothrops atrox venom (BaV). The chemical composition of the aqueous extract of P. reticulata (AEPr) was first investigated by thin-layer chromatography (TLC) and the extract was then fractionated by column chromatography on Sephadex LH-20. This yielded five main fractions (Pr1, Pr2, Pr3, Pr4 and Pr5), which were analyzed by colorimetry to determine their concentrations of total phenolics, total tannins and condensed tannins and to assess their potential for blocking the phospholipase activity of BaV. The Pr5 fraction was defined as the fraction rich in condensed tannins (CTPr), and its inhibitory potential against the activities of the venom was evaluated. CTPr was evaluated in different in vivo and in vitro experimental protocols. The in vivo protocols consisted of (1) pre-incubation (venom:CTPr, w/w), (2) pre-treatment (orally administered) and (3) post-treatment (orally administered) to evaluate the effect on the hemorrhagic and edematogenic activities of BaV; in the in vitro protocol the effect on phospholipase and coagulant activity using pre-incubation in both tests was evaluated. There was statistically significant inhibition (p<0.05) of hemorrhagic activity by CTPr when the pre-incubation protocol was used [55% (1:5, w/w) and 74% (1:10, w/w)] and when pre-treatment with doses of 50 and 100mg/kg was used (19% and 13%, respectively). However, for the concentrations tested, there was no statistically significant inhibition in the group subjected to post-treatment administered orally. CTPr blocked 100% of phospholipase activity and 63.3% (1:10, w/w) of coagulant activity when it was pre

  15. Toxicity of Millettia ferruginea darasana (family: Fabaceae) against the larvae and adult ticks of Amblyomma variegatum Fabricius a three-host tick in cattle.

    Science.gov (United States)

    Choudhury, Manash Kumar; Shiferaw, Yoseph; Hussen, Ahmed

    2015-06-01

    The in vitro toxicity of Millettia ferruginea darasana (family: Fabaceae) was tested against the larvae adult male and female of a three-host tick, Amblyomma variegatum Fabricius (family: Ixodidae or hard tick), known as 'tropical bont tick' parasitic mainly to cattle found in Ethiopia and other equatorial Africa. The 20, 40, 60, 80 and 100 % concentrations of the seed oil extracted with petroleum ether were found to kill all (100 % mortality) larvae after 12, 9, 6, 3 and 1.5 h respectively. The results summarized in the Table 1 was found to be statistically significant at the probability level of p = 0.05. The 100 % concentration of the oil caused 100 % mortality of adult male, adult female and fully engorged female tick after 5, 7 and 12 h respectively. The root and root bark showed less toxicity. The leaves did not show any toxicity. [Table: see text].

  16. Differentiation in a geographical mosaic of plants coevolving with ants: phylogeny of the Leonardoxa africana complex (Fabaceae: Caesalpinioideae) using amplified fragment length polymorphism markers.

    Science.gov (United States)

    Brouat, C; McKey, D; Douzery, E J P

    2004-05-01

    Comprising four allopatric subspecies that exhibit various grades of ant-plant interactions, from diffuse to obligate and symbiotic associations, the Leonardoxa africana complex (Fabaceae, Caesalpinioideae) provides a good opportunity to investigate the evolutionary history of ant-plant mutualisms. A previous study of the L. africana complex based on chloroplast DNA noncoding sequences revealed a lack of congruence between clades suggested by morphological and plastid characters. In this study, we analysed phylogenetic relationships within the L. africana complex using a Bayesian probability approach on amplified fragment length polymorphism markers. The results reported permit partial validation of the four subspecies of L. africana previously defined by morphological and ecological markers. Incongruences between phylogenies based on chloroplast DNA and amplified fragment length polymorphism markers are discussed in the light of morphological and ecological data, and confronted with hypotheses of convergence, lineage sorting and introgression.

  17. Avaliação da toxicidade aguda e potencial neurotóxico do óleo-resina de copaíba (Copaifera reticulata Ducke, Fabaceae

    Directory of Open Access Journals (Sweden)

    Camile Giaretta Sachetti

    Full Text Available O óleo-resina de copaíba obtido do gênero Copaifera L., Fabaceae, é largamente utilizado na medicina popular como antiinflamatório, antimicrobiano e antitumoral. Porém, informações sobre seu potencial tóxico são escassos na literatura. O objetivo deste estudo foi estabelecer a toxicidade oral aguda e os possíveis efeitos neurotóxicos relacionados à ingestão do óleo-resina de Copaifera reticulata Ducke, Fabaceae, em ratas Wistar. O estudo foi conduzido com quinze ratas nulíparas distribuídas nos grupos de doses 300 e 2000 mg/kg pc de óleo-resina administrado por gavagem. Os resultados obtidos mostraram que nestas doses não houve sinais clínicos de toxicidade ou neurotoxicidade, alteração no consumo de ração ou alteração no peso corpóreo. A dose letal aguda foi estimada como maior que 2000 mg/kg pc e classificada como categoria 5, segundo o Guia OECD 423. Estes resultados indicam que existe uma relativa margem de segurança para o uso do óleo-resina de copaíba como agente terapêutico, embora estudos toxicológicos adicionais sejam ainda necessários, principalmente com a administração repetida de baixas doses.

  18. Electronics and electronic systems

    CERN Document Server

    Olsen, George H

    1987-01-01

    Electronics and Electronic Systems explores the significant developments in the field of electronics and electronic devices. This book is organized into three parts encompassing 11 chapters that discuss the fundamental circuit theory and the principles of analog and digital electronics. This book deals first with the passive components of electronic systems, such as resistors, capacitors, and inductors. These topics are followed by a discussion on the analysis of electronic circuits, which involves three ways, namely, the actual circuit, graphical techniques, and rule of thumb. The remaining p

  19. Asociación Thysanoptera (Insecta-Vicia faba (Fabaceae en la Prepuna y Puna de Jujuy, Argentina Thysanoptera (Insecta-Vicia faba (Fabaceae association in Prepuna and Puna in Jujuy, Argentina

    Directory of Open Access Journals (Sweden)

    María Inés Zamar

    2012-03-01

    . occidentalis utilizan la planta en forma temporal y oportunista en Prepuna, mientras que la presencia de F. gemina en Puna es esporádica. Se amplía el número de especies de tisanópteros asociadas al cultivo de haba en ArgentinaThysanoptera (Insecta-Vicia faba (Fabaceae association in Prepuna and Puna in Jujuy, Argentina. The different phenological stages of Vicia faba provide food resources and substrates for the development of a significant diversity of insects. This study aimed to identify the complex of anthophyllous thrips, analyze the species population fluctuations, to obtain some bioecological aspects and the role they play in this association. The study and sampling was conducted during the flowering-fruiting bean crop stages in two phytogeographical regions of Jujuy: Prepuna (2 479m asl on a weekly basis, from October-December 1995-1996 and Puna (3 367m asl every two weeks, from December 2007-March 2008. Each sample consisted of 25 flowers taken at random; only at Prepuna a complementary sampling of three hits per plant (n=10 plants was conducted. Observations were made on oviposition sites, admission to the flower, pupation sites, feeding behavior and injuries caused. In Prepuna, the Thysanoptera complex consisted of Frankliniella australis, F. occidentalis, F. gemina, F. schultzei and Thrips tabaci; in Puna, the specific diversity was restricted to F. australis and F. gemina. Although the planting-harvest period in both areas did not match, the fluctuations in populations showed the same pattern: as flowering progressed, the number of thrips coincided with the availability of food resources. In both areas, F. australis was the dominant species and maintained successive populations; it layed eggs in flower buds, and larvae hatched when flowers opened; feeding larvae and adults brought about silvery stains with black spots. In Prepuna, F. australis went through the mobile immature stages on flowers, while quiescent stages were on the ground; in the Puna, all

  20. Estudo químico de duas plantas medicinais da amazônia: Philodendron scabrum k. Krause (araceae e Vatairea guianensis aubl. (fabaceae Chemical study of two Amazonian medicinal plants: Philodendron scabrum K. Krause (Araceae and Vatairea guianensis Aubl. (Fabaceae

    Directory of Open Access Journals (Sweden)

    Ivonei Ottobelli

    2011-01-01

    Full Text Available Este trabalho relata o estudo químico de duas plantas medicinais da Amazônia: Philodendron scabrum K. krause (Araceae e Vatairea guianensis Aubl. (Fabaceae. As composições dos óleos essenciais dos cipós de P. scabrum e dos frutos de V. guianensis, respectivamente, foram analisadas em CG-DIC e CG-EM. Os constituintes majoritários dos cipós de P. scabrum foram óxido de cariofileno (19,42%, α-copaeno (16,08% e β-bisaboleno (10,01%; e nos frutos de V. guianensis foram o ácido (9Z-octadecenoico (24,95% e o ácido docosahexaenoico (24,17%. β-sitosterol e o alquilresorcinol 1-hexadecanoil-2,6-dihidroxibenzeno foram isolados do extrato etanólico dos cipós de P. scabrum; e do extrato etanólico dos frutos de V. guianensis, foram isoladas as antraquinonas crisofanol e fisciona. As determinações estruturais foram baseadas em dados de RMN de ¹H e 13C. RMN, uni e bidimensional e comparação com dados da literatura.This work describes the chemical study of two medicinal plants of the Amazon Philodendron scabrum K. Krause (Araceae and Vatairea guianensis Aubl. (Fabaceae. Essential oils composition from stems of Philodendron scabrum K. Krause (Araceae and fruits of Vatairea guianensis Aubl. (Fabaceae, respectively were analyzed in GC-FID and GC-MS. The major constituents from stems of P. scarabum were caryophyllene oxide (22.42%, α-copaene (16.08% and β-bisabolene (12.01% and from fruits of V. guianensis were (9Z-octadecenoic acid (24.95% and docosahexenoic acid (24.17%. β-sitosterol and alkylresorcinol 1-hexadecanoyl-2,6-dihydroxybenzene were isolated from ethanolic extracts from stems of P. scabrum and from ethanolic extracts from fruits of V. guianensis, the athraquinones chrysophanol and physcion were isolated. The structure of isolated compounds we determinate wered based on data from ¹H and 13C NMR, including two dimensional analyses and comparison with literature data.

  1. Seasonal variation of phenolic content in galled and non-galled tissues of Calliandra brevipes Benth (Fabaceae: Mimosoidae Variação sazonal do conteúdo fenólico em tecidos galhados e não-galhados de Calliandra brevipes Benth (Fabaceae: Mimosoidae

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    Michelle de Lima Detoni

    2011-09-01

    Full Text Available Two species, Tanaostigmodes ringueleti and T. mecanga, induce distinct galls on Calliandra brevipes Benth (Fabaceae: Mimosoidae, a globose and a fusiform gall morphotype. Seasonal changes of phenolic content in the tissues of the two distinct galls were compared to those of non-galled leaves and stems of the host plants over one year. The variation in the phenolic content profiles was similar in both non-galled and galled tissues, and was primarily associated with changes in the levels of rainfall, indicating a direct response to hydric stress. In periods of drastic changes in water precipitation, the alterations were significantly higher in non-galled than in galled tissues suggesting that the gall inducers might limit the variation in the phenolic concentration for their own benefit.Duas espécies, Tanaostigmodes ringueleti e T. mecanga, induzem galhas distintas em Calliandra brevipes Benth (Fabaceae: Mimosoidae, um morfotipo globoso e um fusiforme. Mudanças sazonais no conteúdo fenólico nos tecidos das duas galhas foram comparadas àquelas de folha e caule não galhados das plantas hospedeiras por um ano. A variação no perfil de conteúdo fenólico foi similar em tecidos galhados e não galhados, sendo associada primariamente às mudanças nos níveis de chuva, constituindo uma resposta direta ao estresse hídrico. Nos períodos de mudanças drásticas na precipitação de água, as alterações foram significativamente maiores em tecido não galhados do que em tecidos galhados, sugerindo que os galhadores estariam limitando a variação do conteúdo fenólico em seu próprio benefício.

  2. Reproductive phenology and sharing of floral resource among hummingbirds (Trochilidae) in inflorescences of Dahlstedtia pinnata (Benth.) Malme. (Fabaceae) in the Atlantic forest.

    Science.gov (United States)

    Missagia, Caio C C; Verçoza, Fábio C; Alves, Maria Alice S

    2014-12-01

    The purpose of this study was to investigate the reproductive phenology and sharing of floral resource (nectar) of Dahlstedtia pinnata (Benth.) Malme. (Fabaceae), endemic of Atlantic forest, among hummingbirds. For the phenology, we looked at the presence of reproductive structures in the plants, and for floral resource sharing, the frequency of potential pollinators and foraging behaviors were examined. This study was conducted in Pedra Branca State Park, in state of Rio de Janeiro, in a dense ombrophilous forest, between August 2010 and August 2011. Flowering occurred between December 2010 and March 2011, and fruiting between April and June 2011. Hummingbirds' foraging schedules differed significantly, with legitimate visits to the flowers occurring in the morning and illegitimate visits occurring during late morning and the afternoon. Five species visited flowers, three of which were legitimate visitors: Phaethornis ruber, P. pretrei, and Ramphodon naevius. Amazilia fimbriata and Thalurania glaucopis females only visited illegitimately. Phaethornis ruber robbed nectar (78% of illegitimate visits, n=337). Ramphodon naevius, with a territorial foraging behavior and a body size bigger than that of other observed hummingbird species, dominated the floral visits, which suggests that D. pinnata is an important nourishing resource for this endemic bird of the Atlantic forest, currently globally categorized as Near Threatened.

  3. Effects of Aqueous Extracts of Copaifera langsdorffii (Fabaceae) on the Growth and Reproduction of Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Sâmia, R R; de Oliveira, R L; Moscardini, V F; Carvalho, G A

    2016-10-01

    Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) is considered a pest of maize crops throughout the Western Hemisphere. We report on the effects of aqueous extracts of leaves and bark of Copaifera langsdorffii (Fabaceae) on the biology of S. frugiperda, as an alternative source of natural bioactive molecules for the sustainable management of this pest. Second instars were sprayed with aqueous extracts prepared with 5% (w/v) plant material and/or fed on an artificial diet containing extracts at a concentration equivalent to 0.25% (w/v) for 17 days. Both leaf and bark extracts of C. langsdorffii significantly reduced S. frugiperda food intake, feces, and larval weight and caused a delay in larval development. Additionally, C. langsdorffii-based extracts increased the oviposition period; induced morphological changes in the eggs, including deformation of the corium and malformation of the micropylar and aeropylar regions; and reduced egg viability. But, aqueous extracts of C. langsdorffii exhibited no negative effects on larval and pupal survival, duration of the pupal stage, survival of pupae, sex ratio, longevity, duration of pre-oviposition period, and female fecundity. Aqueous extracts of leaves and bark of C. langsdorffii are promising alternatives for the control of S. frugiperda in maize crops.

  4. Selective fishing and analysis of xanthine oxidase binders from two Fabaceae species by coupling enzyme functionalized core-shell magnetic nanoparticles with HPLC-MS.

    Science.gov (United States)

    Liu, Liangliang; Shi, Shuyun; Zhao, Huading; Yu, Jingang; Jiang, Xinyu; Chen, Xiaoqing

    2014-01-15

    Xanthine oxidase (XOD) immobilized core-shell magnetic silica (Fe3O4@SiO2-XOD) nanoparticles coupled with high performance liquid chromatography-mass spectrometry (HPLC-MS) was developed to fish out and analyze XOD binders from two Fabaceae species, Puerariae lobata flower and Glycyrrhiza uralensis root. The prepared Fe3O4@SiO2-XOD nanoparticles exhibited good specificity for XOD binders, better dispersion in aqueous solution and reusability than those of Fe3O4-XOD nanoparticles. The amount of XOD immobilized onto Fe3O4@SiO2 nanoparticles was 339.9μg/mg and the activity of Fe3O4@SiO2-XOD nanoparticles remained 95% after ten times usage. The optimum conditions of selective fishing were optimized, and finally incubating pH was set at 7, incubating temperature at 25°C and adsorption time at 30min. Twelve XOD binders were successfully identified from ethyl acetate extract of P. lobata flower and G. uralensis root. The developed method provides a rapid, purposeful and effective way to identify active compounds from natural complex mixtures. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Análise da pluviosidade e do efeito de borda sobre os teores de flavonóides em Bauhinia cheilantha (Bong. Steud., Fabaceae

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    Tadeu J. da S. Peixoto Sobrinho

    Full Text Available Este estudo avaliou a influência do efeito de borda e da pluviosidade sobre a produção de flavonóides em indivíduos de Bauhinia cheilantha (Bong. Steud., Fabaceae, em uma área de caatinga no estado de Pernambuco, Nordeste do Brasil. Foi utilizada metodologia analítica por complexação com cloreto de alumínio para quantificar a concentração de flavonóides contidos nos extratos foliares de B. cheilantha, por meio de espectrofotometria no visível. De forma geral, o efeito de borda afeta a produção de flavonóides, entretanto, não foi possível correlacionar a produção de flavonóides e a pluviosidade, demonstrando que a espécie avaliada utiliza outra estratégia como resposta às pressões ambientais.

  6. Reproductive phenology and sharing of floral resource among hummingbirds (Trochilidae in inflorescences of Dahlstedtia pinnata (Benth. Malme. (Fabaceae in the Atlantic forest

    Directory of Open Access Journals (Sweden)

    CAIO C.C. MISSAGIA

    2014-12-01

    Full Text Available The purpose of this study was to investigate the reproductive phenology and sharing of floral resource (nectar of Dahlstedtia pinnata (Benth. Malme. (Fabaceae, endemic of Atlantic forest, among hummingbirds. For the phenology, we looked at the presence of reproductive structures in the plants, and for floral resource sharing, the frequency of potential pollinators and foraging behaviors were examined. This study was conducted in Pedra Branca State Park, in state of Rio de Janeiro, in a dense ombrophilous forest, between August 2010 and August 2011. Flowering occurred between December 2010 and March 2011, and fruiting between April and June 2011. Hummingbirds' foraging schedules differed significantly, with legitimate visits to the flowers occurring in the morning and illegitimate visits occurring during late morning and the afternoon. Five species visited flowers, three of which were legitimate visitors: Phaethornis ruber, P. pretrei, and Ramphodon naevius. Amazilia fimbriata and Thalurania glaucopis females only visited illegitimately. Phaethornis ruber robbed nectar (78% of illegitimate visits, n=337. Ramphodon naevius, with a territorial foraging behavior and a body size bigger than that of other observed hummingbird species, dominated the floral visits, which suggests that D. pinnata is an important nourishing resource for this endemic bird of the Atlantic forest, currently globally categorized as Near Threatened.

  7. Efecto de las arañas (Arachnida: Araneae como depredadoras de insectos plaga en cultivos de alfalfa (Medicago sativa (Fabaceae en Argentina

    Directory of Open Access Journals (Sweden)

    Andrea Armendano

    2011-12-01

    Full Text Available Effect of spiders (Arachnida: Araneae as predators of insect pest in alfalfa crops (Medicago sativa (Fabaceae in Argentina. Spiders are predators that reduce insect pest populations in agroecosystems. Trials were conducted to measure the selectivity against different insect preys, the daily consumption, effect of predators alone and together with a known number of preys, and the indirect effect of predators on vegetation. For this, experimental units (1x1m were used covered with a fine plastic mesh. Misumenops pallidus, Oxyopes salticus and Araneus sp. were used as generalist predators, and aphids, weevils, locusts, chrysomelids and Lepidoptera larvae as their potential preys. Among the preys offered, the spiders preferred Lepidoptera larvae compared to the other two pests groups (weevils and aphids. The maximum consumption rate was of 93.33% for Lepidoptera larvae, 25.33% for aphids and 11.67% for weevils. The Q Index values for the three species of spiders showed a positive selectivity only for defoliating larvae. O. salticus showed the highest values of consumption rates while Rachiplusia nu was the most consumed. The maximum value of consumption in 24 hours was showed by O. salticus on R. nu (C=2.8. The association of several species of predatory spiders increased the total number of insects captured, and also showed that the addition of spiders caused a decrease in the number of leaves damaged by the effect of lepidopterous larvae. Rev. Biol. Trop. 59 (4: 1651-1662. Epub 2011 December 01

  8. Taxonomic study of Onobrychis transcaspica V. Nikitin (Fabaceae in northeastern of Iran with emphasis on altitudinal effect on morphological characters using floristic marker

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    Zeinab Toluei

    2010-07-01

    Full Text Available Onobrychis Miller is the second largest genus of Fabaceae in Iran with nearly 60 species. These species are used as valuable forage plants. Onobrychis sect. Onobrychis with nearly 15 species in Iran is one of the important sections of the genus. Onobrychis transcaspica V. Nikitin, is one of the species of this section that is distributed in NE of Iran. To determine intraspecific variations in O. transcaspica from taxonomic point of view and effective ecological factor, data were collected using special station method. In this way, four special stations were recognized for O. transcaspica in NE of Iran. Results from floristic data (Floristic composition of each special station analysis with MVSP software by PCO method, led to identification of 3 separate groups that was indicative of existence of intraspecific diversity. Morphometric data analysis of individual collected from each special station, by using 65 vegetative and reproductive characters, with PCO and UPGMA methods, confirmed 3 mentioned floristic groups. Ecologic data analysis with CCA Method showed the presence of 3 phenoecodeme based on 3 morphologic groups resulting from altitudinal variations.

  9. Co-processed extracts of Cassia angustifolia Vahl, Fabaceae, and Maytenus ilicifolia (Schrad. Planch., Celastraceae, for production of high load tablets

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    Verônica M. L. Alves

    2011-06-01

    Full Text Available The aim of this study was to investigate the feasibility of a co-processing technique for improving the manufacturing properties of Maytenus ilicifolia (Schrad. Planch., Celastraceae, and Cassia angustifolia Vahl, Fabaceae, extracts in order to obtain tablets containing a high dose of such extracts. An experimental mixture design was used to optimise the formulation composition. Flowability parameters, such as compressibility index, time flow and angle of repose, were determined. Additional important industrial parameters, such as granulometry, bulk density and moisture stability, were also studied. The results demonstrated that co-processing technique was able to improve the flowability of vegetal extracts, making these materials suitable for a direct compression process. The contour plots revealed that formulations with a higher amount of lactose produced the best flow results as well as a larger particle size and a greater bulk density. Tablets from co-processed extracts containing lactose as majority diluent showed appropriate physical-chemical characteristics and presented a more stable moisture sorption behaviour compared to commercial gelatine capsules.

  10. Characterization of Proanthocyanidins from Parkia biglobosa (Jacq. G. Don. (Fabaceae by Flow Injection Analysis — Electrospray Ionization Ion Trap Tandem Mass Spectrometry and Liquid Chromatography/Electrospray Ionization Mass Spectrometry

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    Wagner Vilegas

    2013-03-01

    Full Text Available The present study investigates the chemical composition of the African plant Parkia biglobosa (Fabaceae roots and barks by Liquid Chromatography - Electrospray Ionization and Direct Injection Tandem Mass Spectrometry analysis. Mass spectral data indicated that B-type oligomers are present, namely procyanidins and prodelphinidins, with their gallate and glucuronide derivatives, some of them in different isomeric forms. The analysis evidenced the presence of up to 40 proanthocyanidins, some of which are reported for the first time. In this study, the antiradical activity of extracts of roots and barks from Parkia biglobosa was evaluated using DPPH method and they showed satisfactory activities.

  11. Electronic technology

    International Nuclear Information System (INIS)

    Kim, Jin Su

    2010-07-01

    This book is composed of five chapters, which introduces electronic technology about understanding of electronic, electronic component, radio, electronic application, communication technology, semiconductor on its basic, free electron and hole, intrinsic semiconductor and semiconductor element, Diode such as PN junction diode, characteristic of junction diode, rectifier circuit and smoothing circuit, transistor on structure of transistor, characteristic of transistor and common emitter circuit, electronic application about electronic equipment, communication technology and education, robot technology and high electronic technology.

  12. Hexavalent chromium-induced differential disruption of cortical microtubules in some Fabaceae species is correlated with acetylation of α-tubulin.

    Science.gov (United States)

    Eleftheriou, Eleftherios P; Adamakis, Ioannis-Dimosthenis S; Michalopoulou, Vasiliki A

    2016-03-01

    The effects of hexavalent chromium [Cr(VI)] on the cortical microtubules (MTs) of five species of the Fabaceae family (Vicia faba, Pisum sativum, Vigna sinensis, Vigna angularis, and Medicago sativa) were investigated by confocal laser scanning microscopy after immunolocalization of total tubulin with conventional immunofluorescence techniques and of acetylated α-tubulin with the specific 6-11B-1 monoclonal antibody. Moreover, total α-tubulin and acetylated α-tubulin were quantified by Western immunoblotting and scanning densitometry. Results showed the universality of Cr(VI) detrimental effects to cortical MTs, which proved to be a sensitive and reliable subcellular marker for monitoring Cr(VI) toxicity in plant cells. However, a species-specific response was recorded, and a correlation of MT disturbance with the acetylation status of α-tubulin was demonstrated. In V. faba, MTs were depolymerized at the gain of cytoplasmic tubulin background and displayed low α-tubulin acetylation, while in P. sativum, V. sinensis, V. angularis, and M. sativa, MTs became bundled and changed orientation from perpendicular to oblique or longitudinal. Bundled MTs were highly acetylated as determined by both immunofluorescence and Western immunoblotting. Tubulin acetylation in P. sativum and M. sativa preceded MT bundling; in V. sinensis it followed MT derangement, while in V. angularis the two phenomena coincided. Total α-tubulin remained constant in all treatments. Should acetylation be an indicator of MT stabilization, it is deduced that bundled MTs became stabilized, lost their dynamic properties, and were rendered inactive. Results of this report allow the conclusion that Cr(VI) toxicity disrupts MTs and deranges the MT-mediated functions either by depolymerizing or stabilizing them.

  13. Phylogeny of palaeotropic Derris-like taxa (Fabaceae) based on chloroplast and nuclear DNA sequences shows reorganization of (infra)generic classifications is needed.

    Science.gov (United States)

    Sirichamorn, Yotsawate; Adema, Frits A C B; Gravendeel, Barbara; van Welzen, Peter C

    2012-11-01

    Palaeotropic Derris-like taxa (family Fabaceae, tribe Millettieae) comprise 6-9 genera. They are well known as important sources of rotenone toxin, which are used as organic insecticide and fish poison. However, their phylogenetic relationships and classification are still problematic due to insufficient sampling and high morphological variability. Fifty species of palaeotropic Derris-like taxa were sampled, which is more than in former studies. Three chloroplast genes (trnK-matK, trnL-F IGS, and psbA-trnH IGS) and nuclear ribosomal ITS /5.8S were analyzed using parsimony and Bayesian methods. Parsimony and Bayesian analyses of individual and combined markers show more or less similar tree topologies (only varying in terminal branches). The old-world monophyletic genera Aganope, Brachypterum, and Leptoderris are distinct from Derris s.s., and their generic status is here confirmed. Aganope may be classified into two or three subgeneric taxa. Paraderris has to be included in Derris s.s. to form a monophyletic group. The genera Philenoptera, Deguelia, and Lonchocarpus are monophyletic and distinct from each other and clearly separate from Derris s.s. Morphologically highly similar species of Derris s.s. are shown to be unrelated. Our study shows that previous infrageneric classifications of Derris are incorrect. Paraderris elliptica may contain several cryptic lineages that need further investigation. The concept of the genus Derris s.s. should be reorganized with a new generic circumscription by including Paraderris but excluding Brachypterum. Synapomorphic morphological features will be examined in future studies, and the status of the newly defined Derris and its closely related taxa will be formalized.

  14. Antihypertensive activity of 80% methanol seed extract of Calpurnia aurea (Ait.) Benth. subsp. aurea (Fabaceae) is mediated through calcium antagonism induced vasodilation.

    Science.gov (United States)

    Getiye, Yohannes; Tolessa, Tesfaye; Engidawork, Ephrem

    2016-08-02

    Calpurnia aurea (Ait.) Benth. subsp. aurea (CASA) (Fabaceae) seeds are used to treat hypertension in Ethiopian folklore medicine, particularly by Shinasha, Agew-awi and Amhara people in northwest Ethiopia. However, the claim has so far not been substantiated scientifically. The study was conducted to evaluate the antihypertensive activity of 80% methanol extract of CASA in animal model of hypertension as well as its vasorelaxant effect and possible underlying mechanisms in isolated guinea pig aorta. Hypotensive and antihypertensive effect of CASA extract was determined in vivo through the intravenous (iv) route in normotensive and hypertensive anesthetized rats using 2-kidney-1-clip (2K1C) rat model. Ex vivo, guinea pig thoracic aortic rings were isolated and suspended in organ bath, and the vasodepressor effects as well as the mechanism of action of the extract were studied by means of isometric tension recording experiments. The blood pressure fell dose-dependently and significantly in renal hypertensive and normotensive rats following i.v. administration, suggesting that the hydroalcoholic extract possesses hypotensive and antihypertensive effects. The extract also caused a dose-dependent relaxation of aorta pre-contracted with KCl at a concentration of 5-250mg/L, with a maximum relaxation of 92.1% achieved at 250mg/L. The relaxation mechanism was found to be independent of the muscarinic receptors, histamine receptors, ATP dependent K(+) channels, cyclooxygenase enzymes, cGMP/NO pathway and the endothelium system. The extract caused rightward shift of the Ca(++) dose-response curves, similar to that caused by verapamil, indicating that it produced vasorelaxation by inhibiting extracellular Ca(2+) influx. The findings demonstrate that the plant is endowed with antihypertensive effect, providing evidence for its traditional use. The effect may be, at least in part, due to dilation of blood vessels through blockage of Ca(2+) channels. Copyright © 2016 Elsevier

  15. Observations préliminaires de la variabilité entre quelques morphotypes de voandzou (Vigna subterranea L. Verdc., Fabaceae de Côte d'Ivoire

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    Zoro Bi IA.

    2005-01-01

    Full Text Available Preliminary observations of variability between some morphotypes of bambara groundnut (Vigna subterranea L. Verdc., Fabaceae from Côte d’Ivoire. Bambara groundnut (Vigna subterranea L. Verdc., is a food legume mainly cultivated by women for whom it represents a source of income for the household. In Côte d’Ivoire, the cultivation of bambara groundnut is located in the western and northern parts of the country. These zones are characterised by contrasted agroecology including tropical rain forest and dry savanna. In these zones, bambara groundnut plays a key role in both food and culture of peoples. Four morphotypes of Côte d’Ivoire (ICU, BPR, RBU, NFU were used in a preliminary study to assess the phenotypic variability between morphotypes. For each morphotype, 100 individuals were sampled to analyse 26 agromorphological traits selected from the list of bambara groundnut descriptors. Results of statistical analyses showed an important variability among morphotypes suggesting that 22 of these characters could be powerful to distinguish diversity among bambara groundnut morphotypes of Côte d’Ivoire. Three morphotypes (ICU, BPR and RBU show a shorter reproductive cycle than the other (NFU. In our experimental conditions, morphotypes with a shorter reproductive cycle give a higher percentage of matured pods (87 to 95%, compared to morphotype NFU (60%. The morphotype ICU was particularly earlier, maturing 90 days after sowing (DAS, whereas the long reproductive cycle morphotype (NFU required about 137 days. Based on the analysed agronomic traits, possibilities to improve bambara groundnut yield and to promote its cultivation in Côte d’Ivoire are discussed.

  16. Ecologie et gestion des espèces multi-usages du genre Erythrophleum (Fabaceae-Caesalpinioideae en Afrique (synthèse bibliographique

    Directory of Open Access Journals (Sweden)

    Gorel, AP.

    2015-01-01

    Full Text Available Ecology and management of the multipurpose Erythrophleum species (Fabaceae-Caesalpinioideae in Africa. A review. Introduction. Widespread in Africa, the Erythrophleum genus includes four tropical tree species with a high economic and socio-cultural value: Erythrophleum ivorense, Erythrophleum suaveolens, Erythrophleum africanum and Erythrophleum lasianthum. Appropriate knowledge of the ecology and the distribution of these species is required for their sustainable management. This paper is based on an extensive literature review and summarizes the available information on the African Erythrophleum species in terms of botany, phylogeography, ecology, forestry and ethnobotany. Literature. Erythrophleum ivorense, E. suaveolens, E. africanum and E. lasianthum are morphologically different and occur in distinct climatic areas. They are non-pioneer light demander (E. ivorense and E. suaveolens or pioneer species (E. africanum. Their primary mode of dispersal is via ballochore. The seeds have a dormancy period and can remain in the soil for several years. Their reproductive and foliar phenologies are regular and annual. Growth rate varies between species, ranging from 0.65 cm per year for E. ivorense to 0.16 cm per year for E. africanum. These trees are used in traditional medicine. Only E. ivorense and E. suaveolens (Tali are mainly logged for timber. Conclusions. Erythrophleum species ecological data are better informed for E. ivorense and E. suaveolens because of their economic importance. This review highlights the existing lack of knowledge regarding the phenology (effects of climate, fructification periods, the minimum diameter of fructification and the mechanisms of natural seed dormancy breakage. Targeting such weaknesses is required to create or re-evaluate methods of conservation and/or enhancement of populations and logging practices.

  17. The Electron

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, George

    1972-01-01

    Electrons are elementary particles of atoms that revolve around and outside the nucleus and have a negative charge. This booklet discusses how electrons relate to electricity, some applications of electrons, electrons as waves, electrons in atoms and solids, the electron microscope, among other things.

  18. Hard electronics; Hard electronics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Hard material technologies were surveyed to establish the hard electronic technology which offers superior characteristics under hard operational or environmental conditions as compared with conventional Si devices. The following technologies were separately surveyed: (1) The device and integration technologies of wide gap hard semiconductors such as SiC, diamond and nitride, (2) The technology of hard semiconductor devices for vacuum micro- electronics technology, and (3) The technology of hard new material devices for oxides. The formation technology of oxide thin films made remarkable progress after discovery of oxide superconductor materials, resulting in development of an atomic layer growth method and mist deposition method. This leading research is expected to solve such issues difficult to be easily realized by current Si technology as high-power, high-frequency and low-loss devices in power electronics, high temperature-proof and radiation-proof devices in ultimate electronics, and high-speed and dense- integrated devices in information electronics. 432 refs., 136 figs., 15 tabs.

  19. Effects of the parasitism of Struthanthus flexicaulis (Mart. Mart. (Loranthaceae on the fitness of Mimosa calodendron Mart. (Fabaceae, an endemic shrub from rupestrian fields over ironstone outcrops, Minas Gerais State, Brazil Efeitos do parasitismo de Struthanthus flexicaulis (Mart. Mart. (Loranthaceae na aptidão de Mimosa calodendron Mart. (Fabaceae, um arbusto endêmico dos campos rupestres sobre canga, em Minas Gerais, Brasil

    Directory of Open Access Journals (Sweden)

    Fabiana Alves Mourão

    2009-09-01

    Full Text Available Parasitic plants (mistletoes may alter the growth, reproduction and physiology of their hosts. Mimosa calodendron (Fabaceae is a legume abundant in rupestrian fields on ironstone outcrops, frequently attacked by the hemiparasite Struthanthus flexicaulis (Loranthaceae. The objective of this study was to evaluate the consequences of parasitism by S. flexicaulis on the fitness of M. calodendron. The intensity of parasitism and mortality on hosts of different sizes was evaluated, and foliage cover, fruit and seed set in parasitized and non-parasitized individuals were compared. More than 65% of a population of 1820 individuals was attacked. Host density positively influenced parasitism. The mortality and number of attacked hosts increased with their crown diameter. Heavily parasitized individuals showed 75 to 95% reduction of leaf cover and fruit production of 25% of those non-parasitized. Although no statistical difference was detected between the number of seeds per fruit, seed weight was lower in attacked plants. Parasitism by S. flexicaulis on M. calodendron may alter its population structure and dynamics, by reducing survival and fecundity rates.As plantas parasitas (ervas-de-passarinho podem alterar o crescimento, reprodução e fisiologia das hospedeiras. Mimosa calodendron (Fabaceae é uma leguminosa abundante nos campos rupestres sobre canga, freqüentemente atacada pela hemiparasita Struthanthus flexicaulis (Loranthaceae. O objetivo deste trabalho foi avaliar as conseqüências do parasitismo de S. flexicaulis na aptidão de M. calodendron. Foram avaliadas a intensidade de parasitismo e mortalidade em mimosas de diferentes tamanhos, e comparadas a cobertura foliar e a produção de frutos e sementes em indivíduos parasitados e não parasitados. Mais de 65% da população de 1.820 indivíduos estavam parasitados. A densidade de mimosas influenciou positivamente o parasitismo. As taxas de parasitismo e de mortalidade foram maiores nas

  20. Feeding behavior of hummingbirds and perching birds on Erythrina speciosa Andrews (Fabaceae flowers in an urban area, Londrina, Paraná, Brazil Comportamento alimentar de beija-flores e Passeriformes nas flores de Erytrhina speciosa Andrews (Fabaceae em uma área urbana de Londrina, Paraná, Brasil

    Directory of Open Access Journals (Sweden)

    Luciana Baza Mendonça

    2006-03-01

    Full Text Available Nine species of birds - seven hummingbirds (Trochilidae and two Passeriformes - were observed visiting the flowers of Erythrina speciosa Andrews (Fabaceae, a hummingbird-pollinated species present on the campus of Londrina State University, Paraná State, Brazil. Nectar in bagged flowers bore little relationship with nectar in flowers opened to foragers either regarding quantity or diurnal pattern of availability. Birds were more frequent early in the morning and their activity on flowers further declined, apparently following the pattern of nectar availability. The manner to which birds probed the flowers and, in consequence, their role on pollination were greatly determined by morphological traits and approaching behavior of birds. E. speciosa seemed best suited for pollination by long-billed hummingbirds but some short to medium-billed species may play some role on its pollination.Nove espécies de aves - sete beija-flores (Trochilidae e duas aves Passeriformes - foram observados visitando as flores de Erythrina speciosa Andrews (Fabaceae, uma espécie polinizada por beija-flores presente no campus da Universidade Estadual de Londrina, Paraná, Brasil. O néctar em flores ensacadas apresentou pouca relação com aquele em flores expostas aos visitantes, tanto em termos de quantidade como em temos de padrão diurno de disponibilidade. As aves foram mais freqüentes de manhã e sua atividade nas flores diminuiu no transcorrer do dia, coincidindo com o padrão de disponibilidade de néctar. O comportamento de visita das aves e, em conseqüência, sua atuação na polinização da espécie foram em grande parte determinadas por características morfológicas e comportamentais destas. E. speciosa parece ser adaptada para polinização por beija-flores de bicos longos, embora espécies com bicos de comprimento curto a médio possam ter algum papel em sua polinização.

  1. Impactos da invasão de Prosopis juliflora (sw. DC. (Fabaceae sobre o estrato arbustivo-arbóreo em áreas de Caatinga no Estado da Paraíba, Brasil = Impact of the invasion of Prosopis juliflora (Sw. DC. (Fabaceae in areas of Caatinga in the state of Paraíba, Brazil

    Directory of Open Access Journals (Sweden)

    Leonaldo Alves de Andrade

    2010-07-01

    Full Text Available Estima-se que as áreas invadidas por algaroba – Prosopis juliflora (Sw. DC. (Fabaceae no semi-árido nordestino já ultrapassam um milhão de hectares. O presente trabalho objetivou estudar os impactos da invasão de P. juliflora sobre a fitodiversidade e a estrutura do componente arbustivo-arbóreo, em remanescentes de caatinga no Estado da Paraíba. Usando-se o método de parcelas, foram amostrados quatro ambientes, nos quais os indivíduos de todas as espécies arbustivas e arbóreas foram inventariados e medidos, estimando-se os parâmetros estruturais das comunidades. Também foi calculada a diversidade, pelo índice de Shannon-Wiener (H’ e o índice de impacto ambiental deexóticas (IIAE. No total, foram amostradas 19 famílias, 35 gêneros e 39 espécies. A invasora foi responsável por mais de 70% de toda a estrutura dos ambientes inventariados. A baixa diversidade e o elevado valor de impacto ambiental obtidos para os ambientes invadidosrevelaram, conjuntamente com os dados de estrutura das populações, os graves impactos que P. juliflora provoca nas comunidades invadidas. Evidencia-se com isso a formação de sistemas monodominados pela espécie invasora, o que revela a necessidade de controle efetivo de P. juliflora para se proteger o patrimônio genético autóctone.It is estimated that invader populations of algaroba Prosopis juliflora (Sw. DC. (Fabaceae in the northeastern semi-arid, Brazil, cover more than one million ha. This study aimed to study the impacts of P. juliflora invasion on phytodiversity and on the structure of the shrub-tree component in caatinga fragments in Paraiba state. Four environments were sampled by plots in which all shrubtree individuals were surveyed and measured, estimating structural parameters of thecommunities. Diversity was estimated by the Shannon-Wiener index (H', and the index of environmental impacts of exotic species (IIAE was also calculated. A total of 19 families, 35 genera and 39

  2. Electron radiography

    Science.gov (United States)

    Merrill, Frank E.; Morris, Christopher

    2005-05-17

    A system capable of performing radiography using a beam of electrons. Diffuser means receive a beam of electrons and diffuse the electrons before they enter first matching quadrupoles where the diffused electrons are focused prior to the diffused electrons entering an object. First imaging quadrupoles receive the focused diffused electrons after the focused diffused electrons have been scattered by the object for focusing the scattered electrons. Collimator means receive the scattered electrons and remove scattered electrons that have scattered to large angles. Second imaging quadrupoles receive the collimated scattered electrons and refocus the collimated scattered electrons and map the focused collimated scattered electrons to transverse locations on an image plane representative of the electrons' positions in the object.

  3. Superação de dormência e influência da temperatura, substrato e fotoperíodo na germinação de sementes de Erythrina crista-galli L. (FABACEAE

    Directory of Open Access Journals (Sweden)

    Luciano Moura de Mello

    2016-11-01

    Full Text Available Erythrina crista-galli L. (FABACEAE é uma árvore nativa do Brasil, Uruguai, Paraguai, Bolívia e Argentina. As Regras de Análises de Sementes - RAS não possuem orientações para a realização de testes de germinação para a espécie. O objetivo deste trabalho foi testar o desempenho de tratamentos para a superação de dormência das sementes e recomendar condições adequadas de substrato, temperatura e fotoperíodo para a realização de testes de germinação. O tratamento indicado para a superação da dormência foi a escarificação mecânica e a temperatura ótima para os testes de germinação de 30ºC constantes. Não houve diferença entre tratamentos em relação aos substratos testados nem quanto aos fotoperíodos indicando-se assim o substrato entre papel e com 8h de luz por sua praticidade e economia. Superação de dormência e influência da temperatura, substrato e fotoperíodo na germinação de sementes de Erythrina crista-galli L. (FABACEAE

  4. Ontogênese, anatomia e ultra-estrutura dos nectários extraflorais de Hymenaea stigonocarpa Mart. ex Hayne (Fabaceae - Caesalpinioideae Ontogenesis, anatomy, and ultrastructure of Hymenaea stigonocarpa Mart. ex Hayne (Fabaceae - Caesalpinioideae extrafloral nectaries

    Directory of Open Access Journals (Sweden)

    Élder Antônio Sousa Paiva

    2006-06-01

    Full Text Available O jatobá-do-cerrado (Hymenaea stigonocarpa Mart. ex Hayne apresenta nectários extraflorais (NEFs, os quais são descritos pela primeira vez no gênero. Neste trabalho foram estudadas a distribuição, ontogênese, estrutura e ultra-estrutura dos nectários extraflorais (NEFs. Amostras de folhas em várias fases de desenvolvimento foram coletadas, fixadas e processadas para estudos em microscopia de luz e eletrônica de transmissão e varredura, segundo técnicas convencionais. Testes histoquímicos foram empregados para determinar a natureza química da secreção. Os NEFs estão distribuídos por todo o limbo, sendo mais concentrados nos terços basal e médio de cada folíolo. Estes nectários são embutidos no mesofilo, apresentam tecido secretor envolvido por uma endoderme e são vascularizados por xilema e floema. A atividade secretora dos NEFs é limitada à fase juvenil da folha. Nas folhas mais velhas, os NEFs tornam-se não funcionais. O tecido secretor dos NEFs é formado a partir da protoderme, enquanto a endoderme tem origem no meristema fundamental. No tecido secretor de nectários funcionais as células apresentam citoplasma denso, núcleo volumoso, mitocôndrias, plastídios com sistema de membranas pouco desenvolvido, gotas de óleo dispersas no citosol, dictiossomos e segmentos de retículo endoplasmático liso. A secreção é liberada por meio de rupturas cuticulares e apresenta polissacarídeos e lipídios.Hymenaea stigonocarpa Mart. ex Hayne, known as "jatobá-do-cerrado" has extrafloral nectaries (EFNs, which are reported for the first time in Hymenaea genus. In this research the origin, distribution, structure, and ultrastructure of the EFNs were studied. Samples of leaflets at different developmental stages were collected, fixed and processed by standard methods for analyses at light and electronic microscopes; histochemical tests were employed to determine the nature of secretion products. EFNs are distributed all over

  5. Electrons, Electronic Publishing, and Electronic Display.

    Science.gov (United States)

    Brownrigg, Edwin B.; Lynch, Clifford A.

    1985-01-01

    Provides a perspective on electronic publishing by distinguishing between "Newtonian" publishing and "quantum-mechanical" publishing. Highlights include media and publishing, works delivered through electronic media, electronic publishing and the printed word, management of intellectual property, and recent copyright-law issues…

  6. ST proteins, a new family of plant tandem repeat proteins with a DUF2775 domain mainly found in Fabaceae and Asteraceae.

    Science.gov (United States)

    Albornos, Lucía; Martín, Ignacio; Iglesias, Rebeca; Jiménez, Teresa; Labrador, Emilia; Dopico, Berta

    2012-11-07

    Many proteins with tandem repeats in their sequence have been described and classified according to the length of the repeats: I) Repeats of short oligopeptides (from 2 to 20 amino acids), including structural cell wall proteins and arabinogalactan proteins. II) Repeats that range in length from 20 to 40 residues, including proteins with a well-established three-dimensional structure often involved in mediating protein-protein interactions. (III) Longer repeats in the order of 100 amino acids that constitute structurally and functionally independent units. Here we analyse ShooT specific (ST) proteins, a family of proteins with tandem repeats of unknown function that were first found in Leguminosae, and their possible similarities to other proteins with tandem repeats. ST protein sequences were only found in dicotyledonous plants, limited to several plant families, mainly the Fabaceae and the Asteraceae. ST mRNAs accumulate mainly in the roots and under biotic interactions. Most ST proteins have one or several Domain(s) of Unknown Function 2775 (DUF2775). All deduced ST proteins have a signal peptide, indicating that these proteins enter the secretory pathway, and the mature proteins have tandem repeat oligopeptides that share a hexapeptide (E/D)FEPRP followed by 4 partially conserved amino acids, which could determine a putative N-glycosylation signal, and a fully conserved tyrosine. In a phylogenetic tree, the sequences clade according to taxonomic group. A possible involvement in symbiosis and abiotic stress as well as in plant cell elongation is suggested, although different STs could play different roles in plant development. We describe a new family of proteins called ST whose presence is limited to the plant kingdom, specifically to a few families of dicotyledonous plants. They present 20 to 40 amino acid tandem repeat sequences with different characteristics (signal peptide, DUF2775 domain, conservative repeat regions) from the described group of 20 to 40

  7. Humidity-regulated dormancy onset in the Fabaceae: a conceptual model and its ecological implications for the Australian wattle Acacia saligna

    Science.gov (United States)

    Tozer, Mark G.; Ooi, Mark K. J.

    2014-01-01

    Background and aims Seed dormancy enhances fitness by preventing seeds from germinating when the probability of seedling survival and recruitment is low. The onset of physical dormancy is sensitive to humidity during ripening; however, the implications of this mechanism for seed bank dynamics have not been quantified. This study proposes a model that describes how humidity-regulated dormancy onset may control the accumulation of a dormant seed bank, and seed experiments are conducted to calibrate the model for an Australian Fabaceae, Acacia saligna. The model is used to investigate the impact of climate on seed dormancy and to forecast the ecological implications of human-induced climate change. Methods The relationship between relative humidity and dormancy onset was quantified under laboratory conditions by exposing freshly matured non-dormant seeds to constant humidity levels for fixed durations. The model was field-calibrated by measuring the response of seeds exposed to naturally fluctuating humidity. The model was applied to 3-hourly records of humidity spanning the period 1972–2007 in order to estimate both temporal variability in dormancy and spatial variability attributable to climatic differences among populations. Climate change models were used to project future changes in dormancy onset. Key Results A sigmoidal relationship exists between dormancy and humidity under both laboratory and field conditions. Seeds ripened under field conditions became dormant following very short exposure to low humidity (<20 %). Prolonged exposure at higher humidity did not increase dormancy significantly. It is predicted that populations growing in a temperate climate produce 33–55 % fewer dormant seeds than those in a Mediterranean climate; however, dormancy in temperate populations is predicted to increase as a result of climate change. Conclusions Humidity-regulated dormancy onset may explain observed variation in physical dormancy. The model offers a systematic

  8. La semilla de Campsiandra angustifolia (Fabaceae:Caesalpiniodeaecomo un reflejo de las presiones selectivas sobre su dispersión y establecimiento

    Directory of Open Access Journals (Sweden)

    Alejandro G Farji-Brener

    2005-06-01

    Full Text Available Evaluamos indirectamente las presiones selectivas sobre la dispersión y el establecimiento en Campsiandra angustifolia, un árbol de la Amazonía Peruana dispersado por agua, analizando variaciones de la relación entre el volumen ocupado por las estructuras de dispersión y de establecimiento en sus semillas. Medimos un total de 535 semillas de 13 árboles ubicados en tres hábitats diferentes, las cuales presentaron una gran variación en su volumen total. Independientemente del tamaño de la semilla y de la ubicación del árbol de origen, la relación entre el volumen asignado a estructuras de establecimiento y a estructuras de dispersión fue relativamente constante (~1 y presentó una distribución normal con baja asimetría, indicando selección estabilizante. Este resultado sugiere que los procesos de dispersión y establecimiento poseen una importancia relativa similar para C.angustifolia en los hábitats estudiados. En especies con semillas empaquetadas, el volumen relativo ocupado por estructuras relacionadas con la dispersión o el establecimiento podría ser una medida más adecuada de la solución de compromiso entre estos dos procesos que la variación del tamaño de la semillaThe seeds of Campsiandra angustifolia (Fabaceae:Caesalpiniodeae as a reflex of selective pressures on dispersal and establishment. We indirectly evaluated the selective pressures on dispersal and establishment of Campsiandra angustifolia, a common water-dispersed tree from the Peruvian Amazon, analyzing the variation in the relationship between the volume occupied by dispersal and establishment structures in a total of 535 seeds from 13 trees located at three different habitats. The seeds differed one order of magnitude in their total volume. However, independently of their size and the location of the maternal tree, the relationship between the volume occupied by dispersal and establishment structures was relatively constant (~1 and showed a normal

  9. Humidity-regulated dormancy onset in the Fabaceae: a conceptual model and its ecological implications for the Australian wattle Acacia saligna.

    Science.gov (United States)

    Tozer, Mark G; Ooi, Mark K J

    2014-09-01

    Seed dormancy enhances fitness by preventing seeds from germinating when the probability of seedling survival and recruitment is low. The onset of physical dormancy is sensitive to humidity during ripening; however, the implications of this mechanism for seed bank dynamics have not been quantified. This study proposes a model that describes how humidity-regulated dormancy onset may control the accumulation of a dormant seed bank, and seed experiments are conducted to calibrate the model for an Australian Fabaceae, Acacia saligna. The model is used to investigate the impact of climate on seed dormancy and to forecast the ecological implications of human-induced climate change. The relationship between relative humidity and dormancy onset was quantified under laboratory conditions by exposing freshly matured non-dormant seeds to constant humidity levels for fixed durations. The model was field-calibrated by measuring the response of seeds exposed to naturally fluctuating humidity. The model was applied to 3-hourly records of humidity spanning the period 1972-2007 in order to estimate both temporal variability in dormancy and spatial variability attributable to climatic differences among populations. Climate change models were used to project future changes in dormancy onset. A sigmoidal relationship exists between dormancy and humidity under both laboratory and field conditions. Seeds ripened under field conditions became dormant following very short exposure to low humidity (humidity did not increase dormancy significantly. It is predicted that populations growing in a temperate climate produce 33-55 % fewer dormant seeds than those in a Mediterranean climate; however, dormancy in temperate populations is predicted to increase as a result of climate change. Humidity-regulated dormancy onset may explain observed variation in physical dormancy. The model offers a systematic approach to modelling this variation in population studies. Forecast changes in climate have

  10. Electron detector

    International Nuclear Information System (INIS)

    Hashimoto, H.; Mogami, A.

    1975-01-01

    A device for measuring electron densities at a given energy level in an electron beam or the like having strong background noise, for example, in the detection of Auger electric energy spectrums is described. An electron analyzer passes electrons at the given energy level and at the same time electrons of at least one adjacent energy level. Detecting means associated therewith produce signals indicative of the densities of the electrons at each energy level and combine these signals to produce a signal indicative of the density of the electrons of the given energy level absent background noise

  11. Anatomia dos órgãos vegetativos de Hymenaea martiana Hayne (Caesalpinioideae-Fabaceae: espécie de uso medicinal em Caetité-BA Anatomy of vegetative organs of Hymenaea martiana Hayne (Fabaceae-Caesalpinioideae: a species of medicinal use in Caetité-Bahia State, Brazil

    Directory of Open Access Journals (Sweden)

    M.S. Silva

    2012-01-01

    Full Text Available Hymenaea martiana Hayne (Fabaceae-Caesalpinioideae apresenta grande valor na medicina popular em Caetité. A casca, entrecasca do caule e a resina, são utilizadas no tratamento de diversos males. Neste estudo são apresentadas a caracterização anatômica e histoquímica dos órgãos vegetativos. Amostras foram coletadas e processadas segundo técnicas usuais em anatomia vegetal e histoquímica. Todos os órgãos apresentam, em visão transversal, epiderme unisseriada e cavidades secretoras. Cutícula espessa ocorre em todos os órgãos aéreos. A raiz é tetrarca. Colênquima lacunar foi encontrado no caule. Bainha de fibras esclerenquimáticas envolve os feixes vasculares dos órgãos aéreos. Células pétreas ocorrem no pecíolo. Tricomas tectores ocorrem em ambas as faces da folha. A folha é hipoestomática com estômatos paracíticos e o mesofilo é dorsiventral. Cristais de oxalato de cálcio ocorrem no caule, pecíolo e lâmina foliar. Compostos fenólicos ocorrem na raiz, pecíolo e nervura central da folha. Grãos de amido ocorrem na raiz, caule e pecíolo. Lipídios ocorrem em todos os órgãos. Acredita-se que compostos fenólicos e cavidades secretoras de resina podem justificar a utilidade medicinal da espécie pela população de Caetité.Hymenaea martiana Hayne (Fabaceae-Caesalpinioideae shows a great value in folk medicine in Caetité. Its bark, stem-bark and resin are used to treat various ailments. In this study, the anatomical and histochemical characterization of vegetative organs is reported. Samples were collected and processed according to usual techniques of plant anatomy and histochemistry. All organs have, by cross-sectional view, uniseriate epidermis and secretory cavities. Thick cuticle occurs in all aerial organs. The root is tetrarch. Lacunar collenchyma was found in the stem. Sclerenchymatic sheath of fibers surrounds the vascular bundles of the aerial organs. Stone cells occur in the petiole. Trichomes occur

  12. Soil organisms associated to the weed suppressant Crotalaria juncea (fabaceae and its importance as a refuge for natural enemies Organismos de solo associados à supressora de plantas daninhas Crotalaria juncea (fabaceae e sua importância como refúgio para inimigos naturais

    Directory of Open Access Journals (Sweden)

    W.S Tavares

    2011-09-01

    Full Text Available Soil organisms play an important role in organic crops of Crotalaria juncea (Fabaceae and are associated with the natural conservation of the environment. The present study was aimed to investigate the population of soil organisms in the organic culture of C. juncea, as well as its importance as a refuge for natural enemies. Dalbulus maidis (Hemiptera: Cicadellidae, Diabrotica sp. (Coleoptera: Chrysomelidae, Doru luteipes (Dermaptera: Forficulidae, Gryllus assimilis (Orthoptera: Gryllidae, Lagria villosa (Coleoptera: Lagriidae, Melanotus sp. (Coleoptera: Elateridae, Meloidogyne incognita (Tylenchida: Heteroderidae, Nephila clavipes (Araneae: Nephilidae, Orius insidiosus (Hemiptera: Anthocoridae, Pheidole sp. (Hymenoptera: Myrmicidae, Phyllophaga sp. (Coleoptera: Scarabeidae, Procornitermes sp. (Isoptera: Termitidae, Solenopsis sp. (Hymenoptera: Formicidae, and Utetheisa ornatrix (Lepidoptera: Arctiidae were identified in C. juncea. The organisms that were found during a 3-month period in 144 trenches in C. juncea were pest species (84.47% and natural enemies (15.53% as well. Natural enemies had an average of 11.89 individuals per 1.08 m³ of soil cultivated with C. juncea. The abundance of organisms in the pod stage (5.49% of C. juncea was lower than that in the vegetative (83.50% and flowering (11.01% stages. Crotalaria juncea plants can be used as part of a crop system for Integrated Pest Management.Organismos de solo desempenham um importante papel em cultivos orgânicos de Crotalaria juncea (Fabaceae e estão associados com a conservação natural do ambiente. O presente estudo teve como objetivo investigar a população de organismos de solo no cultivo orgânico de C. juncea, bem como sua importância como um refúgio para inimigos naturais. Dalbulus maidis (Hemiptera: Cicadellidae, Diabrotica sp. (Coleoptera: Chrysomelidae, Doru luteipes (Dermaptera: Forficulidae, Gryllus assimilis (Orthoptera: Gryllidae, Lagria villosa (Coleoptera

  13. Electron/electron acoustic instability

    International Nuclear Information System (INIS)

    Gary, S.P.

    1987-01-01

    The electron acoustic wave becomes a normal mode of an unmagnetized collisionless plasma in the presence of two electron components with similar densities, but strongly disparate temperatures. The characteristic frequency of this mode is the plasma frequency of the cooler electron component. If these two electron components have a relative drift speed several times the thermal speed of the cooler component, the electron/electron acoustic instability may arise. This paper describes the parametric dependences of the threshold drift speed and maximum growth rate of this instability, and compares these with the same properties of the electron/ion acoustic instability. Under the condition of zero current, the electron/ion acoustic instability typically has the lower threshold drift speed, so that observation of the electron/electron acoustic instability is a strong indication of the presence of an electrical current in the plasma

  14. Efecto de las arañas (Arachnida: Araneae como depredadoras de insectos plaga en cultivos de alfalfa (Medicago sativa (Fabaceae en Argentina

    Directory of Open Access Journals (Sweden)

    Andrea Armendano

    2011-12-01

    Full Text Available Effect of spiders (Arachnida: Araneae as predators of insect pest in alfalfa crops (Medicago sativa (Fabaceae in Argentina. Spiders are predators that reduce insect pest populations in agroecosystems. Trials were conducted to measure the selectivity against different insect preys, the daily consumption, effect of predators alone and together with a known number of preys, and the indirect effect of predators on vegetation. For this, experimental units (1x1m were used covered with a fine plastic mesh. Misumenops pallidus, Oxyopes salticus and Araneus sp. were used as generalist predators, and aphids, weevils, locusts, chrysomelids and Lepidoptera larvae as their potential preys. Among the preys offered, the spiders preferred Lepidoptera larvae compared to the other two pests groups (weevils and aphids. The maximum consumption rate was of 93.33% for Lepidoptera larvae, 25.33% for aphids and 11.67% for weevils. The Q Index values for the three species of spiders showed a positive selectivity only for defoliating larvae. O. salticus showed the highest values of consumption rates while Rachiplusia nu was the most consumed. The maximum value of consumption in 24 hours was showed by O. salticus on R. nu (C=2.8. The association of several species of predatory spiders increased the total number of insects captured, and also showed that the addition of spiders caused a decrease in the number of leaves damaged by the effect of lepidopterous larvae. Rev. Biol. Trop. 59 (4: 1651-1662. Epub 2011 December 01Las arañas son depredadoras capaces de reducir las poblaciones de insectos plaga en agroecosistemas. Para medir la selectividad frente a distintas presas, se realizaron ensayos de consumo diario, efecto de los depredadores aisladamente y en conjunto sobre el número de presas y efecto indirecto de los depredadores sobre la vegetación; se utilizaron jaulas experimentales de 1x1m cubiertas con una fina malla plástica. Misumenops pallidus, Oxyopes salticus y

  15. Caracterización y variación espacio-temporal del néctar en anarthrophyllum desideratum (Fabaceae: Influencia del clima y los polinizadores

    Directory of Open Access Journals (Sweden)

    Valeria Paiaro

    2012-12-01

    Full Text Available En este trabajo se caracterizó el volumen, la concentración y la composición de azúcares del néctar floral en Anarthrophyllum desideratum (DC Benth., un arbusto endémico de la estepa Patagónica polinizado por aves Passeriformes, y se evaluó su variación espacio-temporal. Se analizaron las diferencias entre áreas ecológicas, poblaciones, plantas y años, y las relaciones entre rasgos, la temperatura, precipitación y tasa de visitas de las poblaciones. El néctar mostró un volumen promedio de 8,1 µl, una concentración de 28% y estuvo dominado por hexosas, como en otras especies ornitófilas. Los atributos del néctar estuvieron correlacionados a nivel poblacional, y las diferencias entre poblaciones explicaron la mayor parte de su variabilidad espacial. El volumen y la concentración variaron entre años, mientras que la composición de azúcares se mantuvo constante. La proporción de glucosa disminuyó con el aumento de la temperatura, pero el resto de los caracteres no se asoció con las variaciones climáticas de la región. El volumen de néctar disminuyó a medida que aumentó la tasa de visitas de las poblaciones. Los resultados sugieren la existencia de una importante variación espacio-temporal del néctar en A. desideratum que no respondería a gradientes ambientales simples sino a un escenario complejo con múltiples factores.Characterization and spatio-temporal variation of nectar in Anarthrophyllum desideratum (Fabaceae: Influence of climate and pollinators. In this study we characterized the volume, concentration and sugar composition of floral nectar in Anarthrophyllum desideratum (DC Benth., an endemic shrub from the Patagonian steppe pollinated by Passerine birds, and we evaluated it spatio-temporal variation. We analyzed the differences among ecological areas, populations, plants and years, and the relationships between traits, the temperature, rainfall and visitation rate of populations. Nectar showed an average

  16. Electronic emission and electron guns

    International Nuclear Information System (INIS)

    Roy, Amitava

    2010-01-01

    This paper reviews the process of electron emission from metal surface. Although electrons move freely in conductors like metals, they normally do not leave the metal without some manipulation. In fact, heating and bombardment are the two primary ways in which electrons are emitted through the use of a heating element behind the cathode (termed thermionic emission) or as a result of bombardment with a beam of electrons, ions, or metastable atoms (termed secondary emission). Another important emission mechanism called Explosive Electron Emission (EEE) is also often used in various High Voltage Pulse Power Systems to generate very high current (few hundreds of kA) pulsed electron beams. The electron gun is the device in that it shoots off a continuous (or pulsed) stream of electrons. A brief idea about the evolution of the electron gun components and their basis of functioning are also discussed. (author)

  17. Sticker electronics

    KAUST Repository

    Hussain, Muhammad Mustafa; Torres Sevilla, Galo Andres; Diaz Cordero, Marlon Steven

    2017-01-01

    Electronic stickers may be manufactured on flexible substrates (110, 120, 130) as layers and packaged together. The package may then have an adhesive applied to one side to provide capability for sticking the electronic devices to surfaces

  18. ELECTRONIC SIGNATURES

    African Journals Online (AJOL)

    10332324

    "[to] promote the understanding and, acceptance of and growth in the number of electronic transactions .... Chapter III of the ECT Act is based on the UNCITRAL Model Law on Electronic. Commerce ... Communications Technology Law 146. 22.

  19. Electronic components

    CERN Document Server

    Colwell, Morris A

    1976-01-01

    Electronic Components provides a basic grounding in the practical aspects of using and selecting electronics components. The book describes the basic requirements needed to start practical work on electronic equipment, resistors and potentiometers, capacitance, and inductors and transformers. The text discusses semiconductor devices such as diodes, thyristors and triacs, transistors and heat sinks, logic and linear integrated circuits (I.C.s) and electromechanical devices. Common abbreviations applied to components are provided. Constructors and electronics engineers will find the book useful

  20. Understand electronics

    CERN Document Server

    Bishop, Owen

    2013-01-01

    Understand Electronics provides a readable introduction to the exciting world of electronics for the student or enthusiast with little previous knowledge. The subject is treated with the minimum of mathematics and the book is extensively illustrated.This is an essential guide for the newcomer to electronics, and replaces the author's best-selling Beginner's Guide to Electronics.The step-by-step approach makes this book ideal for introductory courses such as the Intermediate GNVQ.

  1. Electronic Commerce

    OpenAIRE

    Slavko Đerić

    2016-01-01

    Electronic commerce can be defined in different ways. Any definition helps to understand and explain that concept as better as possible.. Electronic commerce is a set of procedures and technologies that automate the tasks of financial transactions using electronic means. Also, according to some authors, electronic commerce is defined as a new concept, which is being developed and which includes process of buying and selling or exchanging products, services or information via computer networks...

  2. Electronic Publishing.

    Science.gov (United States)

    Lancaster, F. W.

    1989-01-01

    Describes various stages involved in the applications of electronic media to the publishing industry. Highlights include computer typesetting, or photocomposition; machine-readable databases; the distribution of publications in electronic form; computer conferencing and electronic mail; collaborative authorship; hypertext; hypermedia publications;…

  3. Vigna subterranea (L.) Verdc. Fabaceae

    African Journals Online (AJOL)

    PR BOKO

    Désinfection en surface des graines et préparation de l'explant. Les graines ont subi un trempage rapide (1min) dans l'éthanol 70 % (v/v), suivi de l'immersion pendant 30 min dans l'hypochlorite de calcium 7 % (m/v). Elles ont ensuite été abondamment rincées dans de l'eau distillée stérile. Après 48 heures d'imbibition à ...

  4. IN Hedysarum coronarium L. (FABACEAE)

    African Journals Online (AJOL)

    Figure 1 : A picture showing an erect plant of H. coronarium at flowering stage. This phenotype is ... LOS : mean height of principal stem at the end of plant development (cm) ;. LHS : mean length of ..... classification factor. Mahalanobis distan-.

  5. and Rooibos (Aspalathus linearis Fabaceae)

    African Journals Online (AJOL)

    0.05) increased the activity of pyruvate kinase in the liver when compared with the diabetic control group. Conclusion: ... include single ring phenolic acids and monomeric flavonoids ... antioxidant properties. The present ..... such as ALT indicates the concentration of .... Joubert E, Gelderblom WC, Louw A, de Beer D. South.

  6. Spectrum of allergenic pollen in Karachi and their characterization using conventional and electron microscopy: Potential candidates for allergy vaccines

    International Nuclear Information System (INIS)

    Parveen, A.; Noori, M.Y.; Qureshi, M.A.

    2015-01-01

    Objective: To study the distribution of naturally growing plants with possible allergenic potential and study their pollen morphology in Karachi, Pakistan. Methodology: We performed field surveys of naturally growing plants with possible allergenic potential and studied their pollen morphology using conventional (light) as well as scanning electron microscopy. Results: About 80 allergenic pollen producing species were identified which are distributed in 45 genera and 9 angiospermic families. Grasses belonging to Graminae are most abundant followed by plants from family Fabaceae (Leguminosae). Highly allergenic weeds were also found widely growing in the city areas belonging to Amaranthaceae/Chenopodiaceae family. Conclusion: Our study provides an updated information about the allergenic plants growing in Karachi city. All desensitization efforts should be designed in accordance to the available information regarding the prevalent allergens in the environment so that appropriate therapy can be given to the affected population. (author)

  7. Sticker electronics

    KAUST Repository

    Hussain, Muhammad Mustafa

    2017-09-08

    Electronic stickers may be manufactured on flexible substrates (110, 120, 130) as layers and packaged together. The package may then have an adhesive applied to one side to provide capability for sticking the electronic devices to surfaces. The stickers can be wrappable, placed on surfaces, glued on walls or mirrors or wood or stone, and have electronics (112, 122, 132) which may or may not be ultrathin. Packaging for the electronic sticker can use polymer on cellulose manufacturing and/or three dimensional (3-D) printing. The electronic stickers may provide lighting capability, sensing capability, and/or recharging capabilities.

  8. Basic electronics

    CERN Document Server

    Holbrook, Harold D

    1971-01-01

    Basic Electronics is an elementary text designed for basic instruction in electricity and electronics. It gives emphasis on electronic emission and the vacuum tube and shows transistor circuits in parallel with electron tube circuits. This book also demonstrates how the transistor merely replaces the tube, with proper change of circuit constants as required. Many problems are presented at the end of each chapter. This book is comprised of 17 chapters and opens with an overview of electron theory, followed by a discussion on resistance, inductance, and capacitance, along with their effects on t

  9. Electronic Commerce and Electronic Business

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    This special issue is motivated by the recent upsurge of research activity in the areas of electronic commerce and electronic business both in India and all over the world. The current ... Monte Carlo methods for pricing financial options are then.

  10. Electronic Government and Electronic Participation

    NARCIS (Netherlands)

    Tambouris, E; Scholl, H.J.; Janssen, M.F.W.H.A.; Wimmer, M.A.; Tarabanis, K; Gascó, M; Klievink, A.J.; Lindgren, I; Milano, M; Panagiotopoulos, P; Pardo, T.A.; Parycek, P; Sæbø, Ø

    2016-01-01

    Electronic government and electronic participation continue to transform the public sector and society worldwide and are constantly being transformed themselves by emerging information and communication technologies.This book presents papers from the 14th International Federation for Information

  11. Electronic Government and Electronic Participation

    NARCIS (Netherlands)

    Tambouris, E.; Scholl, H.J.; Janssen, M.F.W.H.A.; Wimmer, M.A.; Tarabanis, K.; Gascó, M.; Klievink, A.J.; Lindgren, I.; Milano, M.; Panagiotopoulos, P.; Pardo, T.A.; Parycek, P.; Sæbø, O.

    2015-01-01

    Electronic government and electronic participation continue to transform the public sector and society worldwide and are constantly being transformed themselves by emerging information and communication technologies. This book presents papers from the 14th International Federation for Information

  12. Electron Tree

    DEFF Research Database (Denmark)

    Appelt, Ane L; Rønde, Heidi S

    2013-01-01

    The photo shows a close-up of a Lichtenberg figure – popularly called an “electron tree” – produced in a cylinder of polymethyl methacrylate (PMMA). Electron trees are created by irradiating a suitable insulating material, in this case PMMA, with an intense high energy electron beam. Upon discharge......, during dielectric breakdown in the material, the electrons generate branching chains of fractures on leaving the PMMA, producing the tree pattern seen. To be able to create electron trees with a clinical linear accelerator, one needs to access the primary electron beam used for photon treatments. We...... appropriated a linac that was being decommissioned in our department and dismantled the head to circumvent the target and ion chambers. This is one of 24 electron trees produced before we had to stop the fun and allow the rest of the accelerator to be disassembled....

  13. `Twisted' electrons

    Science.gov (United States)

    Larocque, Hugo; Kaminer, Ido; Grillo, Vincenzo; Leuchs, Gerd; Padgett, Miles J.; Boyd, Robert W.; Segev, Mordechai; Karimi, Ebrahim

    2018-04-01

    Electrons have played a significant role in the development of many fields of physics during the last century. The interest surrounding them mostly involved their wave-like features prescribed by the quantum theory. In particular, these features correctly predict the behaviour of electrons in various physical systems including atoms, molecules, solid-state materials, and even in free space. Ten years ago, new breakthroughs were made, arising from the new ability to bestow orbital angular momentum (OAM) to the wave function of electrons. This quantity, in conjunction with the electron's charge, results in an additional magnetic property. Owing to these features, OAM-carrying, or twisted, electrons can effectively interact with magnetic fields in unprecedented ways and have motivated materials scientists to find new methods for generating twisted electrons and measuring their OAM content. Here, we provide an overview of such techniques along with an introduction to the exciting dynamics of twisted electrons.

  14. Caracterização de solos de duas formações de restinga e sua influência na constituição química foliar de Passiflora mucronata Lam. (Passifloraceaee Canavalia rosea (Sw. DC. (Fabaceae Soil characterization of two restinga formations and its influence on leaf chemistry in Passiflora mucronata Lam. (Passifloraceae and Canavalia rosea (Sw. DC. (Fabaceae

    Directory of Open Access Journals (Sweden)

    Jehová Lourenço Junior

    2009-03-01

    Full Text Available As hipóteses sobre o posicionamento das formações de restinga são diversas sendo o gradiente salino e a fertilidade do solo as mais difundidas. Buscando elucidar essas questões, foram analisadas as propriedades dos solos das formações psamófila-reptante (FPR e Palmae (FP bem como a constituição química foliar de C. rosea (Sw. DC. restrita à FPR e P. mucronata Lam., na FP. O solo da FP destacou-se pela maior fertilidade. Maiores teores dos metais Fe, Zn e ISNa foram encontrados em solos da FPR. Não foi detectada a presença de Al nas duas formações. O pH dos solos é alcalino sem diferenças entre as duas formações. Os elementos químicos P, S, Cu e Zn acumulam-se em maiores concentrações em folhas de P. mucronata. C. rosea destacou-se pelos maiores teores foliares de N, Fe e B. Essa Fabaceae mostrou valores superiores do fator de concentração para o Ca, Mg, Fe, Cu e B enquanto que P. mucronata, para o P e Zn. Os resultados obtidos sugerem que as características pedológicas têm papel chave no estabelecimento de C. rosea na FPRe de P. mucronata na FP.Hypotheses as to the position of restinga formations are many, the most widespread being the salinity gradient and soil fertility. In order to elucidate these questions, soil properties of the creeping psammophyte (CPF and Palmae formations (PF as well as leaf chemistry of C. rosea (Sw. DC. restricted to the former and P. mucronata Lam. in the latter were analyzed. The PF soil was more fertile. Higher content of Fe, Zn and ISNa was found in CPF soil. The presence of Al in these two formations was not detected. Soil pH is alkaline, with no difference found between the two formations. The chemical elements P, S, Cu and Zn accumulate in greater concentrations in P. mucronata leaves. C. rosea was distinguished by a higher leaf content of N, Fe and B. This legume showed greater factor of concentration values for Ca, Mg, Fe, Cu and B whereas P. mucronata, for P and Zn. The results

  15. Electronic Commerce

    Directory of Open Access Journals (Sweden)

    Slavko Đerić

    2016-12-01

    Full Text Available Electronic commerce can be defined in different ways. Any definition helps to understand and explain that concept as better as possible.. Electronic commerce is a set of procedures and technologies that automate the tasks of financial transactions using electronic means. Also, according to some authors, electronic commerce is defined as a new concept, which is being developed and which includes process of buying and selling or exchanging products, services or information via computer networks, including the Internet. Electronic commerce is not limited just to buying and selling, but it also includes all pre-sales and after-sales ongoing activities along the supply chain. Introducing electronic commerce, using the Internet and Web services in business, realizes the way to a completely new type of economy - internet economy.

  16. Advanced Electronics

    Science.gov (United States)

    2017-07-21

    AFRL-RV-PS- AFRL-RV-PS- TR-2017-0114 TR-2017-0114 ADVANCED ELECTRONICS Ashwani Sharma 21 Jul 2017 Interim Report APPROVED FOR PUBLIC RELEASE...NUMBER Advanced Electronics 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 62601F 6. AUTHOR(S) 5d. PROJECT NUMBER 4846 Ashwani Sharma 5e. TASK NUMBER...Approved for public release; distribution is unlimited. (RDMX-17-14919 dtd 20 Mar 2018) 13. SUPPLEMENTARY NOTES 14. ABSTRACT The Space Electronics

  17. Electron spectroscopy

    International Nuclear Information System (INIS)

    Hegde, M.S.

    1979-01-01

    An introduction to the various techniques in electron spectroscopy is presented. These techniques include: (1) UV Photoelectron spectroscopy, (2) X-ray Photoelectron spectroscopy, (3) Auger electron spectroscopy, (4) Electron energy loss spectroscopy, (5) Penning ionization spectroscopy and (6) Ion neutralization spectroscopy. The radiations used in each technique, the basis of the technique and the special information obtained in structure determination in atoms and molecules by each technique are summarised. (A.K.)

  18. Polymer electronics

    CERN Document Server

    Hsin-Fei, Meng

    2013-01-01

    Polymer semiconductor is the only semiconductor that can be processed in solution. Electronics made by these flexible materials have many advantages such as large-area solution process, low cost, and high performance. Researchers and companies are increasingly dedicating time and money in polymer electronics. This book focuses on the fundamental materials and device physics of polymer electronics. It describes polymer light-emitting diodes, polymer field-effect transistors, organic vertical transistors, polymer solar cells, and many applications based on polymer electronics. The book also disc

  19. Electronics Industry

    National Research Council Canada - National Science Library

    Bell, Robert; Carroll-Garrison, Martina; Donovan, Daniel; Fisher, John; Guemmer, Paul; Harms, Robert; Kelly, Timothy; Love, Mattie; McReynolds, James; Ward, Ralph

    2006-01-01

    .... Government action to preserve strategic access to semiconductor producers is clearly needed to ensure DoD electronic systems can be built without compromising sensitive technology, though every...

  20. Microfluidic electronics.

    Science.gov (United States)

    Cheng, Shi; Wu, Zhigang

    2012-08-21

    Microfluidics, a field that has been well-established for several decades, has seen extensive applications in the areas of biology, chemistry, and medicine. However, it might be very hard to imagine how such soft microfluidic devices would be used in other areas, such as electronics, in which stiff, solid metals, insulators, and semiconductors have previously dominated. Very recently, things have radically changed. Taking advantage of native properties of microfluidics, advances in microfluidics-based electronics have shown great potential in numerous new appealing applications, e.g. bio-inspired devices, body-worn healthcare and medical sensing systems, and ergonomic units, in which conventional rigid, bulky electronics are facing insurmountable obstacles to fulfil the demand on comfortable user experience. Not only would the birth of microfluidic electronics contribute to both the microfluidics and electronics fields, but it may also shape the future of our daily life. Nevertheless, microfluidic electronics are still at a very early stage, and significant efforts in research and development are needed to advance this emerging field. The intention of this article is to review recent research outcomes in the field of microfluidic electronics, and address current technical challenges and issues. The outlook of future development in microfluidic electronic devices and systems, as well as new fabrication techniques, is also discussed. Moreover, the authors would like to inspire both the microfluidics and electronics communities to further exploit this newly-established field.

  1. Electron holography

    CERN Document Server

    Tonomura, Akira

    1993-01-01

    Holography was devised for breaking through the resolution limit of electron microscopes The advent of a "coherent" field emission electron beam has enabled the use of Electron Holography in various areas of magnetic domain structures observation, fluxon observation in superconductors, and fundamental experiments in physics which have been inaccessible using other techniques After examining the fundamentals of electron holography and its applications to the afore mentioned fields, a detailed discussion of the Aharonov-Bohm effect and the related experiments is presented Many photographs and illustrations are included to elucidate the text

  2. The electron

    International Nuclear Information System (INIS)

    Hestenes, David; Weingartshofer, Antonio

    1991-01-01

    The stupendous successes of the Dirac equation and quantum electro-dynamics have established the electron as the best understood of the fundamental constituents of matter. Nevertheless, physicists agree that the electron still has secrets to reveal. Moreover, powerful new theoretical and experimental tools for probing those secrets have been sharpened during the last decade. This workshop was organized to bring theorists and experimentalists together to discuss their common goal of knowing the electron. Present state and future prospects for progress toward that goal are here described. The theoretical papers encompass a wide range of views on the electron. Several argue that the 'Zitter-bewegung' is more than a mathematical peculiarity of the Dirac equation, that it may well be a real physical phenomenon and worthy of serious study, theoretically and experimentally. Besides generating the electron spin and magnetic moment, the 'Zitterbewegung' may be a vital clue to electron structure and self-interaction. Some of the papers employ a radical new formulation of the Dirac theory which reveals a hidden geo-metric structure in the theory that supports a 'Zitterbewegung' inter-pretation. For the last half century the properties of electrons have been probed primarily by scattering experiments at ever higher energies. Recently, however, two powerful new experimental techniques have emerged capable of giving alternative experimental views of the electron. First, techniques for confining single electrons for long term study have led to the most accurate measurements of the electron magnetic moment. Second, the interaction of high intensity laser fields with atoms and electrons have revealed striking new phenomena such as multiphoton ionization. refs.; figs.; tabs

  3. Printed Electronics

    Science.gov (United States)

    Korkut, Sibel (Inventor); Chiang, Katherine S. (Inventor); Crain, John M. (Inventor); Aksay, Ilhan A. (Inventor); Lettow, John S. (Inventor); Chen, Chuan-Hua (Inventor); Prud'Homme, Robert K. (Inventor)

    2018-01-01

    Printed electronic device comprising a substrate onto at least one surface of which has been applied a layer of an electrically conductive ink comprising functionalized graphene sheets and at least one binder. A method of preparing printed electronic devices is further disclosed.

  4. In vitro antibacterial, antioxidant and cytotoxic activity of acetone leaf extracts of nine under-investigated Fabaceae tree species leads to potentially useful extracts in animal health and productivity.

    Science.gov (United States)

    Dzoyem, Jean P; McGaw, Lyndy J; Eloff, Jacobus N

    2014-05-05

    The Fabaceae family is the second largest family of medicinal plants, containing more than 490 species which are being used as traditional medicine. The aim of this study was to determine the antioxidant and antibacterial activity as well as the cytotoxicity of acetone leaf extracts of nine tree species from the Fabaceae family that have not been investigated well previously for possible use in animal health and production. The antibacterial activity was determined by a serial microdilution method against three Gram-positive and three Gram-negative bacteria. Antioxidant activity was determined using free-radical scavenging assays. The safety of the extracts was ascertained using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay on Vero African green monkey kidney cells. Six of the nine acetone extracts had significant antibacterial activity against at least one of the six bacterial species with (MIC 20-80 μg/mL). The Crotalaria capensis extract had the highest activity against Salmonella typhimurium, followed by Indigofera cylindrica with MICs of 20 μg/mL and 40 μg/mL respectively. The Dalbergia nitidula extract had free radical scavenging capacity (IC50 of 9.31±2.14 μg/mL) close to that of the positive control Trolox in the DPPH assay. The Xylia torreana extract also had high activity (IC50 of 14.56±3.96 μg/mL) in the ABTS assay. There was a good correlation between antioxidant activity and total phenolic content (R2 values>0.8). The extracts had weak or no toxicity to Vero cells, compared to the positive control doxorubicin with the LC50 varying from 10.70±3.47 to 131.98±24.87 μg/mL at the concentrations tested. Extracts of D. nitidula, X. torreana, C. capensis and I. cylindrica had a low cytotoxicity and high antimicrobial and/or antioxidant activity. These species are therefore promising candidates for the development of useful antimicrobial/antioxidant preparations with a low cytotoxicity that may be useful in promoting

  5. Digital electronics

    CERN Document Server

    Morris, John

    2013-01-01

    An essential companion to John C Morris's 'Analogue Electronics', this clear and accessible text is designed for electronics students, teachers and enthusiasts who already have a basic understanding of electronics, and who wish to develop their knowledge of digital techniques and applications. Employing a discovery-based approach, the author covers fundamental theory before going on to develop an appreciation of logic networks, integrated circuit applications and analogue-digital conversion. A section on digital fault finding and useful ic data sheets completes th

  6. Electronic diagrams

    CERN Document Server

    Colwell, Morris A

    1976-01-01

    Electronic Diagrams is a ready reference and general guide to systems and circuit planning and in the preparation of diagrams for both newcomers and the more experienced. This book presents guidelines and logical procedures that the reader can follow and then be equipped to tackle large complex diagrams by recognition of characteristic 'building blocks' or 'black boxes'. The goal is to break down many of the barriers that often seem to deter students and laymen in learning the art of electronics, especially when they take up electronics as a spare time occupation. This text is comprised of nin

  7. Polymer electronics

    CERN Document Server

    Geoghegan, Mark

    2013-01-01

    Polymer electronics is the science behind many important new developments in technology, such as the flexible electronic display (e-ink) and many new developments in transistor technology. Solar cells, light-emitting diodes, and transistors are all areas where plastic electronics is likely to, or is already having, a serious impact on our daily lives. With polymer transistors and light-emitting diodes now being commercialised, there is a clear need for a pedagogic text thatdiscusses the subject in a clear and concise fashion suitable for senior undergraduate and graduate students. The content

  8. Starting electronics

    CERN Document Server

    Brindley, Keith

    2005-01-01

    Starting Electronics is unrivalled as a highly practical introduction for hobbyists, students and technicians. Keith Brindley introduces readers to the functions of the main component types, their uses, and the basic principles of building and designing electronic circuits. Breadboard layouts make this very much a ready-to-run book for the experimenter; and the use of multimeter, but not oscilloscopes, puts this practical exploration of electronics within reach of every home enthusiast's pocket. The third edition has kept the simplicity and clarity of the original. New material

  9. Stretchable electronics

    CERN Document Server

    Someya, Takao

    2012-01-01

    With its comprehensive coverage this handbook and ready reference brings together some of the most outstanding scientists in the field to lay down the undisputed knowledge on how to make electronics stretchable.As such, it focuses on gathering and evaluating the materials, designs, models and technologies that enable the fabrication of fully elastic electronic devices which can sustain high strain. Furthermore, it provides a review of those specific applications that directly benefit from highly compliant electronics, including transistors, photonic devices and sensors. In addition to stre

  10. Electron optics

    CERN Document Server

    Grivet, Pierre; Bertein, F; Castaing, R; Gauzit, M; Septier, Albert L

    1972-01-01

    Electron Optics, Second English Edition, Part I: Optics is a 10-chapter book that begins by elucidating the fundamental features and basic techniques of electron optics, as well as the distribution of potential and field in electrostatic lenses. This book then explains the field distribution in magnetic lenses; the optical properties of electrostatic and magnetic lenses; and the similarities and differences between glass optics and electron optics. Subsequent chapters focus on lens defects; some electrostatic lenses and triode guns; and magnetic lens models. The strong focusing lenses and pris

  11. Electronic identity

    CERN Document Server

    de Andrade, Norberto Nuno Gomes; Argles, David

    2014-01-01

    With the increasing availability of electronic services, security and a reliable means by which identity is verified is essential.Written by Norberto Andrade the first chapter of this book provides an overview of the main legal and regulatory aspects regarding electronic identity in Europe and assesses the importance of electronic identity for administration (public), business (private) and, above all, citizens. It also highlights the role of eID as a key enabler of the economy.In the second chapter Lisha Chen-Wilson, David Argles, Michele Schiano di Zenise and Gary Wills discuss the user-cent

  12. Power Electronics

    DEFF Research Database (Denmark)

    Iov, Florin; Ciobotaru, Mihai; Blaabjerg, Frede

    2008-01-01

    is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss the most...... emerging renewable energy sources, wind energy, which by means of power electronics are changing from being a minor energy source to be acting as an important power source in the energy system. Power electronics is the enabling technology and the presentation will cover the development in wind turbine...... technology from kW to MW, discuss which power electronic solutions are most feasible and used today....

  13. Paper electronics.

    Science.gov (United States)

    Tobjörk, Daniel; Österbacka, Ronald

    2011-05-03

    Paper is ubiquitous in everyday life and a truly low-cost substrate. The use of paper substrates could be extended even further, if electronic applications would be applied next to or below the printed graphics. However, applying electronics on paper is challenging. The paper surface is not only very rough compared to plastics, but is also porous. While this is detrimental for most electronic devices manufactured directly onto paper substrates, there are also approaches that are compatible with the rough and absorptive paper surface. In this review, recent advances and possibilities of these approaches are evaluated and the limitations of paper electronics are discussed. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Electron Microprobe

    Data.gov (United States)

    Federal Laboratory Consortium — The JEOL JXA-8600 is a conventional hairpin filament thermal emission electron microprobe that is more than 20 years old. It is capable of performing qualitative and...

  15. Electronic Aggression

    Centers for Disease Control (CDC) Podcasts

    Aggression is no longer limited to the school yard. New forms of electronic media, such as blogs, instant messaging, chat rooms, email, text messaging, and the internet are providing new arenas for youth violence to occur.

  16. Electron Emitters

    National Research Council Canada - National Science Library

    Tzeng, Yonhua

    2002-01-01

    When two carbon-nanotube coated electrodes are placed at a small distance from each other, electron emission from carbon nanotubes allows a DC or AC electrical current to flow between these two electrodes...

  17. Electronic plants

    Science.gov (United States)

    Stavrinidou, Eleni; Gabrielsson, Roger; Gomez, Eliot; Crispin, Xavier; Nilsson, Ove; Simon, Daniel T.; Berggren, Magnus

    2015-01-01

    The roots, stems, leaves, and vascular circuitry of higher plants are responsible for conveying the chemical signals that regulate growth and functions. From a certain perspective, these features are analogous to the contacts, interconnections, devices, and wires of discrete and integrated electronic circuits. Although many attempts have been made to augment plant function with electroactive materials, plants’ “circuitry” has never been directly merged with electronics. We report analog and digital organic electronic circuits and devices manufactured in living plants. The four key components of a circuit have been achieved using the xylem, leaves, veins, and signals of the plant as the template and integral part of the circuit elements and functions. With integrated and distributed electronics in plants, one can envisage a range of applications including precision recording and regulation of physiology, energy harvesting from photosynthesis, and alternatives to genetic modification for plant optimization. PMID:26702448

  18. Electronic Elections

    DEFF Research Database (Denmark)

    Schürmann, Carsten

    2009-01-01

    Electronic voting technology is a two edged sword. It comes with many risks but brings also many benefits. Instead of flat out rejecting the technology as uncontrollably dangerous, we advocate in this paper a different technological angle that renders electronic elections trustworthy beyond...... the usual levels of doubt. We exploit the trust that voters currently have into the democratic process and model our techniques around that observation accordingly. In particular, we propose a technique of trace emitting computations to record the individual steps of an electronic voting machine...... for a posteriori validation on an acceptably small trusted computing base. Our technology enables us to prove that an electronic elections preserves the voter’s intent, assuming that the voting machine and the trace verifier are independent....

  19. Electronic commerce

    OpenAIRE

    Zvolánková, Pavla

    2010-01-01

    The thesis deals with a description of electronic commerce from its beginning up to present situation in this area. It explains basic terms connected with electronic commerce and it summarizes the relevant legislation. Moreover it describes e-contracts and rights and duties of both contractual parties. The main view is the view of Internet retailer, which is reflected in the practical part focused on concrete problems of retailers.

  20. Impactos da invasão de Prosopis juliflora (sw. DC. (Fabaceae sobre o estrato arbustivo-arbóreo em áreas de Caatinga no Estado da Paraíba, Brasil - doi: 10.4025/actascibiolsci.v32i3.4535 Impact of the invasion of Prosopis juliflora (Sw. DC. (Fabaceae in areas of Caatinga in the state of Paraiba, Brazil - doi: 10.4025/actascibiolsci.v32i3.4535

    Directory of Open Access Journals (Sweden)

    Juliano Ricardo Fabricante

    2010-09-01

    Full Text Available Estima-se que as áreas invadidas por algaroba – Prosopis juliflora (Sw. DC. (Fabaceae no semi-árido nordestino já ultrapassam um milhão de hectares. O presente trabalho objetivou estudar os impactos da invasão de P. juliflora sobre a fitodiversidade e a estrutura do componente arbustivo-arbóreo, em remanescentes de caatinga no Estado da Paraíba. Usando-se o método de parcelas, foram amostrados quatro ambientes, nos quais os indivíduos de todas as espécies arbustivas e arbóreas foram inventariados e medidos, estimando-se os parâmetros estruturais das comunidades. Também foi calculada a diversidade, pelo índice de Shannon-Wiener (H’ e o índice de impacto ambiental de exóticas (IIAE. No total, foram amostradas 19 famílias, 35 gêneros e 39 espécies. A invasora foi responsável por mais de 70% de toda a estrutura dos ambientes inventariados. A baixa diversidade e o elevado valor de impacto ambiental obtidos para os ambientes invadidos revelaram, conjuntamente com os dados de estrutura das populações, os graves impactos que P. juliflora provoca nas comunidades invadidas. Evidencia-se com isso a formação de sistemas monodominados pela espécie invasora, o que revela a necessidade de controle efetivo de P. juliflora para se proteger o patrimônio genético autóctone.It is estimated that invader populations of algaroba Prosopis juliflora (Sw. DC. (Fabaceae in the northeastern semi-arid, Brazil, cover more than one million ha. This study aimed to study the impacts of P. juliflora invasion on phytodiversity and on the structure of the shrub-tree component in caatinga fragments in Paraiba state. Four environments were sampled by plots in which all shrub-tree individuals were surveyed and measured, estimating structural parameters of the communities. Diversity was estimated by the Shannon-Wiener index (H', and the index of environmental impacts of exotic species (IIAE was also calculated. A total of 19 families, 35 genera and 39

  1. Printed Electronics

    Science.gov (United States)

    Wade, Jessica; Hollis, Joseph Razzell; Wood, Sebastian

    2018-04-01

    The combination of printing technology with manufacturing electronic devices enables a new paradigm of printable electronics, where 'smart' functionality can be readily incorporated into almost any product at low cost. Over recent decades, rapid progress has been made in this field, which is now emerging into the industrial andcommercial realm. However, successful development and commercialisation on a large scale presents some significant technical challenges. For fully-printable electronic systems, all the component parts must be deposited from solutions (inks), requiring the development of new inorganic, organic and hybrid materials.A variety of traditional printing techniques are being explored and adapted forprinting these new materials in ways that result in the best performing electronicdevices. Whilst printed electronics research has initially focused on traditional typesof electronic device such as light-emitting diodes, transistors, and photovoltaics, it is increasingly apparent that a much wider range of applications can be realised. The soft and stretchable nature of printable materials makes them perfect candidates forbioelectronics, resulting in a wealth of research looking at biocompatible printable inks and biosensors. Regardless of application, the properties of printed electronicmaterials depend on the chemical structures, processing conditions, device architecture,and operational conditions, the complex inter-relationships of which aredriving ongoing research. We focus on three particular 'hot topics', where attention is currently focused: novel materials, characterisation techniques, and device stability. With progress advancing very rapidly, printed electronics is expected to grow over the next decade into a key technology with an enormous economic and social impact.

  2. Molecular Electronics

    DEFF Research Database (Denmark)

    Jennum, Karsten Stein

    This thesis includes the synthesis and characterisation of organic compounds designed for molecular electronics. The synthesised organic molecules are mainly based on two motifs, the obigo(phenyleneethynylenes) (OPE)s and tetrathiafulvalene (TTF) as shown below. These two scaffolds (OPE and TTF......) are chemically merged together to form cruciform-like structures that are an essential part of the thesis. The cruciform molecules were subjected to molecular conductance measurements to explore their capability towards single-crystal field-effect transistors (Part 1), molecular wires, and single electron......, however, was obtained by a study of a single molecular transistor. The investigated OPE5-TTF compound was captured in a three-terminal experiment, whereby manipulation of the molecule’s electronic spin was possible in different charge states. Thus, we demonstrated how the cruciform molecules could...

  3. Electron tube

    Science.gov (United States)

    Suyama, Motohiro [Hamamatsu, JP; Fukasawa, Atsuhito [Hamamatsu, JP; Arisaka, Katsushi [Los Angeles, CA; Wang, Hanguo [North Hills, CA

    2011-12-20

    An electron tube of the present invention includes: a vacuum vessel including a face plate portion made of synthetic silica and having a surface on which a photoelectric surface is provided, a stem portion arranged facing the photoelectric surface and made of synthetic silica, and a side tube portion having one end connected to the face plate portion and the other end connected to the stem portion and made of synthetic silica; a projection portion arranged in the vacuum vessel, extending from the stem portion toward the photoelectric surface, and made of synthetic silica; and an electron detector arranged on the projection portion, for detecting electrons from the photoelectric surface, and made of silicon.

  4. Spin electronics

    CERN Document Server

    Buhrman, Robert; Daughton, James; Molnár, Stephan; Roukes, Michael

    2004-01-01

    This report is a comparative review of spin electronics ("spintronics") research and development activities in the United States, Japan, and Western Europe conducted by a panel of leading U.S. experts in the field. It covers materials, fabrication and characterization of magnetic nanostructures, magnetism and spin control in magnetic nanostructures, magneto-optical properties of semiconductors, and magnetoelectronics and devices. The panel's conclusions are based on a literature review and a series of site visits to leading spin electronics research centers in Japan and Western Europe. The panel found that Japan is clearly the world leader in new material synthesis and characterization; it is also a leader in magneto-optical properties of semiconductor devices. Europe is strong in theory pertaining to spin electronics, including injection device structures such as tunneling devices, and band structure predictions of materials properties, and in development of magnetic semiconductors and semiconductor heterost...

  5. Electronic Commerce

    Energy Technology Data Exchange (ETDEWEB)

    Laird, N. [NRG Information Services Inc., Calgary, AB (Canada)

    1995-11-01

    The concept of electronic commerce in the gas industry was discussed. It was defined as the integration of communication technology, advanced information processing capability and business standards, to improve effectiveness of the business process. Examples of electronic data interchange from the automotive, airline, and banking industry were given. The objective of using this technology in the gas industry was described as the provision of one electronic facility to make seamless contractual and operational arrangements for moving natural gas across participating pipelines. The benefit of seamless integration - one readily available standard system used by several companies - was highlighted. A list of value-added services such as the free movement of bulletins, directories, nominations,and other documents was provided.

  6. Electron accelerator

    International Nuclear Information System (INIS)

    Abramyan.

    1981-01-01

    The USSR produces an electron accelerator family of a simple design powered straight from the mains. The specifications are given of accelerators ELITA-400, ELITA-3, ELT-2, TEUS-3 and RIUS-5 with maximum electron energies of 0.3 to 5 MeV, a mean power of 10 to 70 kW operating in both the pulsed and the continuous (TEUS-3) modes. Pulsed accelerators ELITA-400 and ELITA-3 and RIUS-5 in which TESLA resonance transformers are used are characterized by their compact size. (Ha)

  7. Electronic cigarette

    OpenAIRE

    Wang, Tao

    2016-01-01

    As we know E-cigarette is becoming increasingly popular all over the world. It is a new product that the most of smoking people would like to buy and use. However, we are not realizing advantages and disadvantages of e-cigarette clearly. My objective was to research the development of electronic cigarette whether it is under control or a good way of marketing. The thesis has two main parts. They include answers to questions what is electronic cigarette and how to manage the whole industry...

  8. Electronic School.

    Science.gov (United States)

    Executive Educator, 1994

    1994-01-01

    This issue of "The Electronic School" features a special forum on computer networking. Articles specifically focus on network operating systems, cabling requirements, and network architecture. Tom Wall argues that virtual reality is not yet ready for classroom use. B.J. Novitsky profiles two high schools experimenting with CD-ROM…

  9. Electronic Government

    DEFF Research Database (Denmark)

    Wimmer, Maria A.; Traunmüller, Roland; Grönlund, Åke

    This book constitutes the refereed proceedings of the 4th International Conference on Electronic Government, EGOV 2005, held in Copenhagen, Denmark, in August 2005. The 30 revised papers presented were carefully reviewed and selected from numerous submissions, and assess the state-of-the-art in e-government/e-governance...

  10. Electronics department

    International Nuclear Information System (INIS)

    1979-01-01

    This report summarizes the activities in 1978 of some of the groups within the Electronics Department. The work covered includes plant protection and operator studies, reliability techniques, application of nuclear techniques to mineral exploration, applied laser physics, computing and, lastly, research instrumentation. (author)

  11. Power electronics

    Indian Academy of Sciences (India)

    Kishore Chatterjee

    This special issue of Sadhana is a compilation of papers selected from those presented at the 7th National Power. Electronics Conference (NPEC), held at the Indian Institute of Technology, Bombay, on 21–23 December 2015. From among the papers presented in NPEC-2017, selected papers were peer-reviewed for ...

  12. Electron linacs

    Energy Technology Data Exchange (ETDEWEB)

    Loew, G A; Schriber, S O [ed.

    1976-11-01

    A study was made of the present status of the thousand or so electron linacs in the world, and future trends in the field. These machines were classified according to their use: medical, industrial, and nuclear physics. In the medical category, two types of electron linacs are discussed: the conventional ones which are used for x-ray and electron therapy, and those which may in the future be used for negative pion therapy. Industrial machines discussed include linacs for radiographic and other specialized applications. In the nuclear physics category, the status of conventional low- and medium-energy as well as high duty cycle linacs is reviewed. The question of how one might obtain a c-w, 1 GeV, 100..mu..A electron linac is raised, and various options using recirculation and stretchers are examined. In this connection, the status of rf superconductivity is summarized. A review is given of linacs for injectors into synchrotrons and e/sup +-/ storage rings, and recent work done to upgrade the only multi-GeV linac, namely SLAC, is described.

  13. Greening Electronics

    DEFF Research Database (Denmark)

    Pizzol, Massimo; Søes Kokborg, Morten; Thomsen, Marianne

    Based on a literature review with focus on hazardous substances in waste electric and electronic equipment (WEEE) and numbers from a Danish treatment facility a flow analysis for specific substances has been conducted. Further, the accessible knowledge on human and environmental effects due...

  14. Electronic seal

    International Nuclear Information System (INIS)

    Musyck, E.

    1981-01-01

    An electronic seal is presented for a volume such as container for fissile materials. The seal encloses a lock for barring the space as well as a device for the detection and the recording of the intervention of the lock. (AF)

  15. Nuclear electronics

    International Nuclear Information System (INIS)

    Friese, T.

    1981-09-01

    A short survey is given on nuclear radiation detectors and nuclear electronics. It is written for newcomers and those, who are not very familiar with this technique. Some additional information is given on typical failures in nuclear measurement systems. (orig.) [de

  16. Electron linacs

    International Nuclear Information System (INIS)

    Loew, G.A.

    1976-01-01

    To study the present status of the thousand or so electron linacs in the world, and future trends in the field, we have classified these machines according to their use: medical, industrial, and nuclear physics. In the medical category, two types of electron linacs are discussed: the conventional ones which are used for X-ray and electron therapy, and those which may in the future be used for negative pion therapy. The section on industrial machines includes linacs for radiographic and other specialized applications. In the nuclear physics category, the status of conventional low- and medium-energy as well as high duty cycle linacs is reviewed. The question of how one might obtain a C.W., 1 GeV, 100 μA electron linac is raised and various options using recirculation and stretchers are examined. In this connection, the status of RF superconductivity is summarized. Following, there is a review of linacs for injectors into synchrotrons and e +- storage rings. The paper ends with a description of recent work done to upgrade the only multi-GeV linac, namely SLAC. (author)

  17. Electronic Nose and Electronic Tongue

    Science.gov (United States)

    Bhattacharyya, Nabarun; Bandhopadhyay, Rajib

    Human beings have five senses, namely, vision, hearing, touch, smell and taste. The sensors for vision, hearing and touch have been developed for several years. The need for sensors capable of mimicking the senses of smell and taste have been felt only recently in food industry, environmental monitoring and several industrial applications. In the ever-widening horizon of frontier research in the field of electronics and advanced computing, emergence of electronic nose (E-Nose) and electronic tongue (E-Tongue) have been drawing attention of scientists and technologists for more than a decade. By intelligent integration of multitudes of technologies like chemometrics, microelectronics and advanced soft computing, human olfaction has been successfully mimicked by such new techniques called machine olfaction (Pearce et al. 2002). But the very essence of such research and development efforts has centered on development of customized electronic nose and electronic tongue solutions specific to individual applications. In fact, research trends as of date clearly points to the fact that a machine olfaction system as versatile, universal and broadband as human nose and human tongue may not be feasible in the decades to come. But application specific solutions may definitely be demonstrated and commercialized by modulation in sensor design and fine-tuning the soft computing solutions. This chapter deals with theory, developments of E-Nose and E-Tongue technology and their applications. Also a succinct account of future trends of R&D efforts in this field with an objective of establishing co-relation between machine olfaction and human perception has been included.

  18. Electronics Industry

    Science.gov (United States)

    2007-01-01

    countries in developing market nations in Asia (such as Korea, Taiwan, Singapore, Malaysia , China and Vietnam). The competition for the knowledge, economic...Intel, Infineon Technologies, STMicroelectronics, Samsung Electronics, Texas Instruments, AMD Spansion, Philips Semiconductor, Freescale... Samsung ($19.7B), #5 Toshiba ($9.8B), #6 TSMC ($9.7B), #7 Hynix ($8.0B) and #8 Renesas ($7.9B) (McGrath, 2007, p. 3). Samsung , headquartered in

  19. Electronic banking

    OpenAIRE

    Gradišnik, Monika

    2017-01-01

    The development of information and communication technology is one of the most important reasons for the incredibly fast changes in business. Electronic commerce is spreading unstoppably in the operations of companies. The creation of new models, such as online banking, online shopping and the like, has sped up the development of the World Wide Web. Owing to the rapid progress of the World Wide Web and technologies for secure business operations, we can barely imagine life today without e...

  20. Electronic Aggression

    Centers for Disease Control (CDC) Podcasts

    2007-11-20

    Aggression is no longer limited to the school yard. New forms of electronic media, such as blogs, instant messaging, chat rooms, email, text messaging, and the internet are providing new arenas for youth violence to occur.  Created: 11/20/2007 by National Center for Injury Prevention and Control, Division of Violence Prevention.   Date Released: 11/28/2007.

  1. ELECTRON GUN

    Science.gov (United States)

    Christofilos, N.C.; Ehlers, K.W.

    1960-04-01

    A pulsed electron gun capable of delivering pulses at voltages of the order of 1 mv and currents of the order of 100 amperes is described. The principal novelty resides in a transformer construction which is disposed in the same vacuum housing as the electron source and accelerating electrode structure of the gun to supply the accelerating potential thereto. The transformer is provided by a plurality of magnetic cores disposed in circumferentially spaced relation and having a plurality of primary windings each inductively coupled to a different one of the cores, and a helical secondary winding which is disposed coaxially of the cores and passes therethrough in circumferential succession. Additional novelty resides in the disposition of the electron source cathode filament input leads interiorly of the transformer secondary winding which is hollow, as well as in the employment of a half-wave filament supply which is synchronously operated with the transformer supply such that the transformer is pulsed during the zero current portions of the half-wave cycle.

  2. Electronic sputtering

    International Nuclear Information System (INIS)

    Johnson, R.E.

    1989-01-01

    Electronic sputtering covers a range of phenomena from electron and photon stimulated desorption from multilayers to fast heavy ion-induced desorption (sputtering) of biomolecules. In this talk the author attempted. Therefore, to connect the detailed studies of argon ejection from solid argon by MeV ions and keV electrons to the sputtering of low temperatures molecular ices by MeV ions then to biomolecule ejection from organic solids. These are related via changing (dE/dx) e , molecular size, and transport processes occurring in materials. In this regard three distinct regions of (dE/dx) e have been identified. Since the talk this picture has been made explicit using a simple spike model for individual impulsive events in which spike interactions are combined linearly. Since that time also the molecular dynamics programs (at Virginia and Uppsala) have quantified both single atom and dimer processes in solid Ar and the momentum transport in large biomolecule sputtering. 5 refs

  3. Detectors - Electronics

    International Nuclear Information System (INIS)

    Bregeault, J.; Gabriel, J.L.; Hierle, G.; Lebotlan, P.; Leconte, A.; Lelandais, J.; Mosrin, P.; Munsch, P.; Saur, H.; Tillier, J.

    1998-01-01

    The reports presents the main results obtained in the fields of radiation detectors and associated electronics. In the domain of X-ray gas detectors for the keV range efforts were undertaken to rise the detector efficiency. Multiple gap parallel plate chambers of different types as well as different types of X → e - converters were tested to improve the efficiency (values of 2.4% at 60 KeV were reached). In the field of scintillators a study of new crystals has been carried out (among which Lutetium orthosilicate). CdTe diode strips for obtaining X-ray imaging were studied. The complete study of a linear array of 8 CdTe pixels has been performed and certified. The results are encouraging and point to this method as a satisfying solution. Also, a large dimension programmable chamber was used to study the influence of temperature on the inorganic scintillators in an interval from -40 deg. C to +150 deg. C. Temperature effects on other detectors and electronic circuits were also investigated. In the report mentioned is also the work carried out for the realization of the DEMON neutron multidetector. For neutron halo experiments different large area Si detectors associated with solid and gas position detectors were realized. In the frame of a contract with COGEMA a systematic study of Li doped glasses was undertaken aiming at replacing with a neutron probe the 3 He counters presently utilized in pollution monitoring. An industrial prototype has been realised. Other studies were related to integrated analog chains, materials for Cherenkov detectors, scintillation probes for experiments on fundamental processes, gas position sensitive detectors, etc. In the field of associated electronics there are mentioned the works related to the multidetector INDRA, data acquisition, software gamma spectrometry, automatic gas pressure regulation in detectors, etc

  4. Electronic materials

    CERN Document Server

    Kwok, H L

    2010-01-01

    The electronic properties of solids have become of increasing importance in the age of information technology. The study of solids and materials, while having originated from the disciplines of physics and chemistry, has evolved independently over the past few decades. The classical treatment of solid-state physics, which emphasized classifications, theories and fundamental physical principles, is no longer able to bridge the gap between materials advances and applications. In particular, the more recent developments in device physics and technology have not necessarily been driven by new conc

  5. Electronic wastes

    Science.gov (United States)

    Regel-Rosocka, Magdalena

    2018-03-01

    E-waste amount is growing at about 4% annually, and has become the fastest growing waste stream in the industrialized world. Over 50 million tons of e-waste are produced globally each year, and some of them end up in landfills causing danger of toxic chemicals leakage over time. E-waste is also sent to developing countries where informal processing of waste electrical and electronic equipment (WEEE) causes serious health and pollution problems. A huge interest in recovery of valuable metals from WEEE is clearly visible in a great number of scientific, popular scientific publications or government and industrial reports.

  6. Electron gun

    International Nuclear Information System (INIS)

    Chen, H.-Y.; Hughes, R.H.

    1979-01-01

    The invention described relates to cathode ray tubes, and particularly to color picture tubes of the type useful in home television receivers and therefore to electron guns. The invention is especially applicable to self-converging tube-yoke combinations with shadow mask tubes of the type having plural-beam in-line guns disposed in a horizontal plane, an apertured mask with vertically oriented slit-shaped apertures, and a screen with vertically oriented phosphor stripes. The invention is not, however, limited to use in such tubes and may in fact be used, e.g., in dot-type shadow mask tubes and index-type tubes. (Auth.)

  7. Bolometer electronics

    International Nuclear Information System (INIS)

    Groenig, D.E.

    1981-01-01

    High quality is required to the electronic which works with bolometer made of metal for measuring the radiation power in plasmaphysical experiments. If the bandwidth is to be 1 kHz, and the time constant of the bolometer is about 160 ms by high overall gain the critical parameters are the noise of the amplifier, pick up to the system, stability and decoupling of common mode signals. The high overall gain is necessary to be able to measure lowest radiation power. The design made is a good approach to the desired property. (orig.) [de

  8. Basic electronics

    CERN Document Server

    Tayal, DC

    2010-01-01

    The second edition of this book incorporates the comments and suggestions of my friends and students who have critically studied the first edition. In this edition the changes and additions have been made and subject matter has been rearranged at some places. The purpose of this text is to provide a comprehensive and up-to-date study of the principles of operation of solid state devices, their basic circuits and application of these circuits to various electronic systems, so that it can serve as a standard text not only for universities and colleges but also for technical institutes. This book

  9. Nuclear electronics

    International Nuclear Information System (INIS)

    Lucero B, E.

    1989-01-01

    The rapid technical development of Colombia over the past years, resulted among others, a considerable increase in the number of measuring instrumentation and testing laboratories, scientific research and metrology centers, in industry, agriculture, public health, education on the nuclear field, etc. IAN is a well organized institution with qualified management, trained staff and reasonably equipped laboratories to carry out tasks as: Metrology, standardization, quality control and maintenance and repair of nuclear instruments. The government of Colombia has adopted a policy to establish and operate through the country maintenance and repair facilities for nuclear instrumentation. This policy is reflected in the organization of electronic laboratories in Bogota-IAN

  10. Practical electronics handbook

    CERN Document Server

    Sinclair, Ian R

    2013-01-01

    Practical Electronics Handbook, Third Edition provides the frequently used and highly applicable principles of electronics and electronic circuits.The book contains relevant information in electronics. The topics discussed in the text include passive and active discrete components; linear and digital I.C.s; microprocessors and microprocessor systems; digital-analogue conversions; computer aids in electronics design; and electronic hardware components.Electronic circuit constructors, service engineers, electronic design engineers, and anyone with an interest in electronics will find the book ve

  11. Electron foreshock

    International Nuclear Information System (INIS)

    Klimas, A.J.

    1985-01-01

    ISEE particle and wave data are noted to furnish substantial support for the basic features of the velocity dispersed model at the foreshock boundary that was proposed by Filbert and Kellogg (1979). Among many remaining discrepancies between this model and observation, it is noted that unstable reduced velocity distributions have been discovered behind the thin boundary proposed by the model, and that these are at suprathermal energies lying far below those explainable in terms of an oscillating, two-stream instability. Although the long-theorized unstable beam of electrons has been found in the foreshock, there is still no ready explanation of the means by which it could have gotten there. 16 references

  12. Sustainable Management of Electronics

    Science.gov (United States)

    To provide information on EPAs strategy for electronics stewardship, certified electronics recyclers and the Challenge; as well as where to donate unwanted electronics, how to calculate benefits, and what's going on with electronics mgmt in their states.

  13. Advanced electron beam techniques

    International Nuclear Information System (INIS)

    Hirotsu, Yoshihiko; Yoshida, Yoichi

    2007-01-01

    After 100 years from the time of discovery of electron, we now have many applications of electron beam in science and technology. In this report, we review two important applications of electron beam: electron microscopy and pulsed-electron beam. Advanced electron microscopy techniques to investigate atomic and electronic structures, and pulsed-electron beam for investigating time-resolved structural change are described. (author)

  14. EDITORIAL: Synaptic electronics Synaptic electronics

    Science.gov (United States)

    Demming, Anna; Gimzewski, James K.; Vuillaume, Dominique

    2013-09-01

    Conventional computers excel in logic and accurate scientific calculations but make hard work of open ended problems that human brains handle easily. Even von Neumann—the mathematician and polymath who first developed the programming architecture that forms the basis of today's computers—was already looking to the brain for future developments before his death in 1957 [1]. Neuromorphic computing uses approaches that better mimic the working of the human brain. Recent developments in nanotechnology are now providing structures with very accommodating properties for neuromorphic approaches. This special issue, with guest editors James K Gimzewski and Dominique Vuillaume, is devoted to research at the serendipitous interface between the two disciplines. 'Synaptic electronics', looks at artificial devices with connections that demonstrate behaviour similar to synapses in the nervous system allowing a new and more powerful approach to computing. Synapses and connecting neurons respond differently to incident signals depending on the history of signals previously experienced, ultimately leading to short term and long term memory behaviour. The basic characteristics of a synapse can be replicated with around ten simple transistors. However with the human brain having around 1011 neurons and 1015 synapses, artificial neurons and synapses from basic transistors are unlikely to accommodate the scalability required. The discovery of nanoscale elements that function as 'memristors' has provided a key tool for the implementation of synaptic connections [2]. Leon Chua first developed the concept of the 'The memristor—the missing circuit element' in 1971 [3]. In this special issue he presents a tutorial describing how memristor research has fed into our understanding of synaptic behaviour and how they can be applied in information processing [4]. He also describes, 'The new principle of local activity, which uncovers a minuscule life-enabling "Goldilocks zone", dubbed the

  15. Acute and sub-chronic toxicity studies of three plants used in Cameroonian ethnoveterinary medicine: Aloe vera (L.) Burm. f. (Xanthorrhoeaceae) leaves, Carica papaya L. (Caricaceae) seeds or leaves, and Mimosa pudica L. (Fabaceae) leaves in Kabir chicks.

    Science.gov (United States)

    Nghonjuyi, Ndaleh Wozerou; Tiambo, Christian Keambou; Taïwe, Germain Sotoing; Toukala, Jean Paul; Lisita, Frederico; Juliano, Raquel Soares; Kimbi, Helen Kuokuo

    2016-02-03

    Aloe vera (L.) Burm. f. (Xanthorrhoeaceae), Carica papaya L. (Caricaceae) and Mimosa pudica L. (Fabaceae) are widely used in the Cameroonian ethnoveterinary medicine as a panacea, and specifically for gastrointestinal disorders as well as an anthelmintic and antibacterial. The present study evaluated the potential toxicity of the hydroalcoholic extracts of Aloe vera leaves, Carica papaya leaves or seeds, and Mimosa pudica leaves after acute and sub-chronic administration in chicks. For the acute toxicity test a single administration of each of the four hydroalcoholic extracts was given orally at doses ranging from 40 to 5120 mg/kg (n=5/group/sex). In the sub-chronic study, these extracts were given orally as a single administration to chicks at doses of 80, 160, 320 and 640 mg/kg/day for 42 days. The anti-angiogenic properties of these extracts (5-320 µg/mg) were investigated in the chick chorioallantoic membrane in vivo. In the acute toxicity test, none of the four studied hydroalcoholic extracts induced mortality or significant behavioural changes. The sub-acute treatment with the four plant extracts did not alter either the body weight gain or the food and water consumption. However, the results indicated that Aloe vera leaf extract acute treatment by oral route at doses up to 2560 mg/kg did not produce death in 50% (5/10) of chicks during 24h or 14 days of observation, but 20% (2/10) chicks died. The haematological and biochemical analyses did not show significant differences in any of the parameters examined in female or male groups, with the exception of a transient rise in white blood cell counts at high doses (640 mg/kg). Additionally, these extracts did not have the potential for anti-angiogenic effects through the inhibition of neo-angiogenesis in the chick chorioallantoic membrane in vivo. The results showed that the therapeutic use of the hydroalcoholic extracts of Aloe vera leaves, Carica papaya leaves or seeds and Mimosa pudica leaves had very low

  16. Large-scale pattern of genetic differentiation within African rainforest trees: insights on the roles of ecological gradients and past climate changes on the evolution of Erythrophleum spp (Fabaceae).

    Science.gov (United States)

    Duminil, Jerome; Brown, Richard P; Ewédjè, Eben-Ezer B K; Mardulyn, Patrick; Doucet, Jean-Louis; Hardy, Olivier J

    2013-09-12

    The evolutionary events that have shaped biodiversity patterns in the African rainforests are still poorly documented. Past forest fragmentation and ecological gradients have been advocated as important drivers of genetic differentiation but their respective roles remain unclear. Using nuclear microsatellites (nSSRs) and chloroplast non-coding sequences (pDNA), we characterised the spatial genetic structure of Erythrophleum (Fabaceae) forest trees in West and Central Africa (Guinea Region, GR). This widespread genus displays a wide ecological amplitude and taxonomists recognize two forest tree species, E. ivorense and E. suaveolens, which are difficult to distinguish in the field and often confused. Bayesian-clustering applied on nSSRs of a blind sample of 648 specimens identified three major gene pools showing no or very limited introgression. They present parapatric distributions correlated to rainfall gradients and forest types. One gene pool is restricted to coastal evergreen forests and corresponds to E. ivorense; a second one is found in gallery forests from the dry forest zone of West Africa and North-West Cameroon and corresponds to West-African E. suaveolens; the third gene pool occurs in semi-evergreen forests and corresponds to Central African E. suaveolens. These gene pools have mostly unique pDNA haplotypes but they do not form reciprocally monophyletic clades. Nevertheless, pDNA molecular dating indicates that the divergence between E. ivorense and Central African E. suaveolens predates the Pleistocene. Further Bayesian-clustering applied within each major gene pool identified diffuse genetic discontinuities (minor gene pools displaying substantial introgression) at a latitude between 0 and 2°N in Central Africa for both species, and at a longitude between 5° and 8°E for E. ivorense. Moreover, we detected evidence of past population declines which are consistent with historical habitat fragmentation induced by Pleistocene climate changes. Overall

  17. Efeito da temperatura e luz na germinação de sementes de Luetzelburgia auriculata (Alemão Ducke - Fabaceae The effect of temperature and light on Luetzelburgia auriculata (Alemão Ducke seed germination

    Directory of Open Access Journals (Sweden)

    Francisco Carlos Barboza Nogueira

    2012-12-01

    Full Text Available Luetzelburgia auriculata (Alemão Ducke é uma espécie arbórea nativa do Brasil, pertencente à família das Fabaceae, importante pela utilidade econômica de sua madeira na construção civil, marcenaria e produção de lenha e carvão. O experimento foi conduzido em laboratório para avaliar o processo germinativo de suas sementes, na ausência e presença de luz, submetido às temperaturas constantes de 20, 25, 30, 35, 40 °C e alternada de 20-40 °C, sob fotoperíodo de 12 horas e escuro contínuo. As variáveis avaliadas foram porcentagem, velocidade e tempo médio de germinação. As sementes germinaram na presença e na ausência de luz, com as maiores médias alcançadas em 20-40 °C, 20 °C, 25 °C, 30 °C e 35 °C e as menores em 40 °C. Suas sementes são indiferentes à luz. A faixa ótima de temperatura entre 25 a 30 °C possibilitou alta germinabilidade e menor tempo médio de germinação.Luetzelburgia auriculata (Alemão Ducke is a native tree species in Brazil with wood that is economically important in construction, carpentry and production of firewood and charcoal. A laboratory experiment was carried out to analyze seed germination of L. auriculata in the presence and absence of light, as well as constant temperatures of 20, 25, 30, 35, 40 °C and alternating temperatures of 20-45 °C, all under a photoperiod of 12 hours and continuous darkness. The variables evaluated were: percentage, speed and medium time of germination. The seeds germinated in the presence and absence of light, the highest percentages of germination were at 20-40, 20, 25, 30 and 35 °C and the lowest at 40 °C. The seeds were indifferent to light. The optimum temperature range was between 25 and 30 °C, which promoted a high germination rate and a lower average germination time.

  18. Carbon Nanotube Electron Gun

    Science.gov (United States)

    Nguyen, Cattien V. (Inventor); Ribaya, Bryan P. (Inventor)

    2013-01-01

    An electron gun, an electron source for an electron gun, an extractor for an electron gun, and a respective method for producing the electron gun, the electron source and the extractor are disclosed. Embodiments provide an electron source utilizing a carbon nanotube (CNT) bonded to a substrate for increased stability, reliability, and durability. An extractor with an aperture in a conductive material is used to extract electrons from the electron source, where the aperture may substantially align with the CNT of the electron source when the extractor and electron source are mated to form the electron gun. The electron source and extractor may have alignment features for aligning the electron source and the extractor, thereby bringing the aperture and CNT into substantial alignment when assembled. The alignment features may provide and maintain this alignment during operation to improve the field emission characteristics and overall system stability of the electron gun.

  19. Electron-electron Bremsstrahlung for bound target electrons

    International Nuclear Information System (INIS)

    Haug, E.

    2008-01-01

    For the process of electron-electron (e-e) Bremsstrahlung the momentum and energy distributions of the recoiling electrons are calculated in the laboratory frame. In order to get the differential cross section and the photon spectrum for target electrons which are bound to an atom, these formulae are multiplied by the incoherent scattering function and numerically integrated over the recoil energy. The effect of atomic binding is most pronounced at low energies of the incident electrons and for target atoms of high atomic numbers. The results are compared to those of previous calculations. (authors)

  20. Descripción, distribución, anatomía, composición química y usos de Mimosa tenuiflora (Fabaceae-Mimosoideae en México

    Directory of Open Access Journals (Sweden)

    Sara Lucía Camargo-Ricalde

    2000-12-01

    Full Text Available A partir de una serie de catástrofes ocurridas en México durante la década de 1980, se popularizó el uso de la corteza del "tepescohuite" contra heridas y quemaduras de la piel. Los medios de comunicación masiva manejaron la escasa información hasta entonces conocida y desinformaron a la sociedad, propagando una serie de mitos alrededor de esta planta. El objetivo de este trabajo fue determinar la identidad taxonómica e investigar la distribución y anatomía de la corteza y de la madera de esta especie. También se investigaron sus usos actuales e históricos y se recopiló información sobre la farmacología y toxicidad de la corteza. Su identidad taxonómica se determina como Mimosa tenuiflora (Willd. Poir. (Fabaceae-Mimosoideae. Florece y fructifica de noviembre a junio y se localiza en México (estados de Oaxaca y Chiapas, Guatemala, Honduras, El Salvador, Nicaragua, Panamá, Colombia, Venezuela y Brasil, en altitudes de 0-1110 (-1520 msnm. En México se establece en selvas bajas, matorrales espinosos, en bosques de Pinus y de Pinus-Quercus, pudiendo formar matorrales casi puros de esta especie, así como a la orilla de caminos y en terrenos de cultivo en descanso o abandonados. Su distribución es agregada en los bosques y en las selvas y uniforme en los matorrales. Presenta una densidad promedio de 9 individuos por m², con 0.45 individuos de frecuencia por cuadrante y una cobertura promedio de 1.69 m²; además, tiene una gran amplitud de tolerancia a factores climáticos y edáficos, ratificando que es una especie de carácter oportunista y típicamente secundaria. Regionalmente, se utiliza como fuente de madera para combustible y postes para cercas, en medicina popular se usa contra heridas y quemaduras de la piel (infusión, polvo y/o pomada a partir de la corteza; además, se comercializan diversos productos como champúes, cremas, cápsulas, jabones, etc. La corteza es rugosa, de color café rojizo a grisácea, de textura

  1. Electron Beam Generation in Tevatron Electron Lenses

    International Nuclear Information System (INIS)

    Kamerdzhiev, V.; Kuznetsov, G.; Shiltsev, V.; Solyak, N.; Tiunov, M.

    2006-01-01

    New type of high perveance electron guns with convex cathode has been developed. Three guns described in this article are built to provide transverse electron current density distributions needed for Electron Lenses for beam-beam compensation in the Tevatron collider. The current distribution can be controlled either by the gun geometry or by voltage on a special control electrode located near cathode. We present the designs of the guns and report results of beam measurements on the test bench. Because of their high current density and low transverse temperature of electrons, electron guns of this type can be used in electron cooling and beam-beam compensation devices

  2. Electron beam generation in Tevatron electron lenses

    International Nuclear Information System (INIS)

    Kamerdzhiev, V.; Kuznetsov, G.; Shiltsev, V.; Solyak, N.; Tiunov, M.

    2006-01-01

    New type of high perveance electron guns with convex cathode has been developed. Three guns described in this article are built to provide transverse electron current density distributions needed for Electron Lenses for beam-beam compensation in the Tevatron collider. The current distribution can be controlled either by the gun geometry or by voltage on a special control electrode located near cathode. We present the designs of the guns and report results of beam measurements on the test bench. Because of their high current density and low transverse temperature of electrons, electron guns of this type can be used in electron cooling and beam-beam compensation devices

  3. Interplay between electron-phonon and electron-electron interactions

    International Nuclear Information System (INIS)

    Roesch, O.; Gunnarsson, O.; Han, J.E.; Crespi, V.H.

    2005-01-01

    We discuss the interplay between electron-electron and electron-phonon interactions for alkali-doped fullerides and high temperature superconductors. Due to the similarity of the electron and phonon energy scales, retardation effects are small for fullerides. This raises questions about the origin of superconductivity, since retardation effects are believed to be crucial for reducing effects of the Coulomb repulsion in conventional superconductors. We demonstrate that by treating the electron-electron and electron-phonon interactions on an equal footing, superconductivity can be understood in terms of a local pairing. The Jahn-Teller character of the important phonons in fullerides plays a crucial role for this result. To describe effects of phonons in cuprates, we derive a t-J model with phonons from the three-band model. Using exact diagonalization for small clusters, we find that the anomalous softening of the half-breathing phonon as well as its doping dependence can be explained. By comparing the solution of the t-J model with the Hartree-Fock approximation for the three-band model, we address results obtained in the local-density approximation for cuprates. We find that genuine many-body results, due to the interplay between the electron-electron and electron-phonon interactions, play an important role for the the results in the t-J model. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  4. Electronics for LHC Experiments

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This document gathers the abstracts of most presentations made at this workshop on electronics for the large hadron collider (LHC) experiments. The presentations were arranged into 6 sessions: 1) electronics for tracker, 2) trigger electronics, 3) detector control systems, 4) data acquisition, 5) electronics for calorimeters and electronics for muons, and 6) links, power systems, grounding and shielding, testing and quality assurance.

  5. Electronics for LHC Experiments

    International Nuclear Information System (INIS)

    2004-01-01

    This document gathers the abstracts of most presentations made at this workshop on electronics for the large hadron collider (LHC) experiments. The presentations were arranged into 6 sessions: 1) electronics for tracker, 2) trigger electronics, 3) detector control systems, 4) data acquisition, 5) electronics for calorimeters and electronics for muons, and 6) links, power systems, grounding and shielding, testing and quality assurance

  6. Electronics and Information

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Previously founded as CCPITMachinery and Electronics Sub-council and CCOIC Machinery and Electronics Chamber of Corn-merce in June, 1988, CCPIT Electronics Sub-Council and CCOIC Electronics Chamber of Commerce were established in May, 1993, and then renamed as CCPIT Electronics and Information Industry Sub-council and CCOIC Electronics and Infor-mation Industry Chamber of Commerce (CCPITECC) in September 1999.

  7. Electron-electron coincidence spectroscopies at surfaces

    International Nuclear Information System (INIS)

    Stefani, G.; Iacobucci, S.; Ruocco, A.; Gotter, R.

    2002-01-01

    In the past 20 years, a steadily increasing number of electron-electron coincidence experiments on atoms and molecules have contributed to a deeper understanding of electron-electron correlation effects. In more recent years this technique has been extended to the study of solid surfaces. This class of one photon IN two electrons OUT experiments will be discussed with an emphasis on grazing incidence geometry, that is expected to be particularly suited for studying surfaces. The crucial question of which is the dominant mechanism that leads to ejection of pairs of electron from the surface will be addressed. It will be shown that, depending on the kinematics chosen, the correlated behaviour of the pairs of electrons detected might be singled out from independent particle one

  8. Electron Microscopy Center (EMC)

    Data.gov (United States)

    Federal Laboratory Consortium — The Electron Microscopy Center (EMC) at Argonne National Laboratory develops and maintains unique capabilities for electron beam characterization and applies those...

  9. Steroids isolated from Millettia versicolor Baker (Fabaceae)

    African Journals Online (AJOL)

    STORAGESEVER

    2008-06-03

    Jun 3, 2008 ... African Journal of Biotechnology Vol. 7 (11), pp. ... Full Length Research Paper ... of Millettia versicolor Baker, a medicinal plant used in the traditional ... The spectral analysis enabled us to identify 4 known .... evidence for participation of protein kinase C and protein kinase A ... Neoplasma 51(6): 407-414.

  10. Rhizobial infection in Adesmia bicolor (Fabaceae) roots.

    Science.gov (United States)

    Bianco, Luciana

    2014-09-01

    The native legume Adesmia bicolor shows nitrogen fixation efficiency via symbiosis with soil rhizobia. The infection mechanism by means of which rhizobia infect their roots has not been fully elucidated to date. Therefore, the purpose of the present study was to identify the infection mechanism in Adesmia bicolor roots. To this end, inoculated roots were processed following conventional methods as part of our root anatomy study, and the shape and distribution of root nodules were analyzed as well. Neither root hairs nor infection threads were observed in the root system, whereas infection sites-later forming nodules-were observed in the longitudinal sections. Nodules were found to form between the main root and the lateral roots. It can be concluded that in Adesmia bicolor, a bacterial crack entry infection mechanism prevails and that such mechanism could be an adaptive strategy of this species which is typical of arid environments.

  11. Indigofera tinctoria Linn (Fabaceae) attenuates cognitive and ...

    African Journals Online (AJOL)

    The cognitive-enhancing activity of the ITE (5, 10 and 20 μg/mL) was studied by passive avoidance response, elevated plus ... preserving brain functions and forestalling ... °C until use. Animals .... scopolamine-induced decreased percentage.

  12. The legume manifesto: (Networkers on Fabaceae, unite!

    Directory of Open Access Journals (Sweden)

    Mikić Aleksandar

    2011-01-01

    Full Text Available Legumes have been an important part of cropping systems since the dawn of agriculture. The shift in Europe from draught animals to meat animals coincided with the increasing availability of soybean meal from North and South America, and the Common Agricultural Policy of the European Union promoted the growing of cereals and oilseeds at the expense of other crops so legumes fell out of favour with farmers and decision-makers. Continental concerns about food and feed security, high prices of oil and soybean meal and advances in the application of fundamental molecular genetics to crop species, all mean that now is a good opportunity to promote the return of legumes to European cropping systems by enhancing the efficiency of research and development on this family. Hence we propose the establishment of a Legume Society that will promote information exchange and scientific productivity by uniting the various legume research communities.

  13. Indigofera tinctoria Linn (Fabaceae) attenuates cognitive and ...

    African Journals Online (AJOL)

    Results: Scopolamine-induced cognitive deficits were significantly reversed by ITE (p < 0.001 at 20 mg/kg) in a dose-dependent fashion in all the behavioral paradigms tested. Furthermore, ITE dosedependently scavenged lipid peroxide, superoxide and hydroxyl free radicals with 50 % inhibition concentration (IC50) of 7.28 ...

  14. Plasmaspheric electron content

    International Nuclear Information System (INIS)

    Hartmann, G.K.

    1978-01-01

    Measurements of the plasmaspheric electron content are reviewed with particular reference to the ATS-6 radio beacon experiment. From the review, it appears likely that measurement of the plasmaspheric electron content is the only one capable of monitoring electron fluxes continuously between L 1 and L 2. Some recent important results deduced from plasmaspheric electron content measurements are discussed

  15. Introduction to electronics

    CERN Multimedia

    CERN. Geneva

    2005-01-01

    Electronics in HEP experiments: specificities and evolution The Art of Electronics: is there something beyond Ohm's law? Basic building blocks of Analog electronics: quickly understanding a schematic Charge preamps, current preamps and future preamps, shaping and the rest Electronics noise: fundamental and practical Evolution of technology: ASICs, FPGAs...

  16. Introduction to Electronics course

    CERN Multimedia

    CERN. Geneva HR-RFA

    2006-01-01

    Electronics in HEP experiments: specificities and evolution The Art of Electronics: is there something beyond Ohm's law? Basic building blocks of Analog electronics: quickly understanding a schematic Charge preamps, current preamps and future preamps, shaping and the rest Electronics noise: fundamental and practical Evolution of technology: ASICs, FPGAs...

  17. Electronics engineer's reference book

    CERN Document Server

    Mazda, F F

    1989-01-01

    Electronics Engineer's Reference Book, Sixth Edition is a five-part book that begins with a synopsis of mathematical and electrical techniques used in the analysis of electronic systems. Part II covers physical phenomena, such as electricity, light, and radiation, often met with in electronic systems. Part III contains chapters on basic electronic components and materials, the building blocks of any electronic design. Part IV highlights electronic circuit design and instrumentation. The last part shows the application areas of electronics such as radar and computers.

  18. Electron transfer reactions

    CERN Document Server

    Cannon, R D

    2013-01-01

    Electron Transfer Reactions deals with the mechanisms of electron transfer reactions between metal ions in solution, as well as the electron exchange between atoms or molecules in either the gaseous or solid state. The book is divided into three parts. Part 1 covers the electron transfer between atoms and molecules in the gas state. Part 2 tackles the reaction paths of oxidation states and binuclear intermediates, as well as the mechanisms of electron transfer. Part 3 discusses the theories and models of the electron transfer process; theories and experiments involving bridged electron transfe

  19. Electron-electron interactions in artificial graphene

    Science.gov (United States)

    Rasanen, Esa

    2013-03-01

    Recent advances in the creation and modulation of graphenelike systems are introducing a science of ``designer Dirac materials.'' In its original definition, artificial graphene is a man-made nanostructure that consists of identical potential wells (quantum dots) arranged in an adjustable honeycomb lattice in the two-dimensional electron gas. As our ability to control the quality of artificial graphene samples improves, so grows the need for an accurate theory of its electronic properties, including the effects of electron-electron interactions. Here we determine those effects on the band structure and on the emergence of Dirac points, and discuss future investigations and challenges in this field.

  20. Electronic payment systems

    OpenAIRE

    Mláka, Michal

    2010-01-01

    This bachelor thesis analysis issue of electronic payment systems. It discusses their use for payments on the internet and sending funds via e-mail. The first part is devoted to the theoretical definition and legislation of the issuance of electronic money and activities of electronic money institutions. The main part of the work clearly focuses on the use of e-wallets, which is an integral part of electronic payment systems. E-wallet of electronic payment system Moneybookers is considered as...

  1. Electronics engineer's reference book

    CERN Document Server

    Turner, L W

    1976-01-01

    Electronics Engineer's Reference Book, 4th Edition is a reference book for electronic engineers that reviews the knowledge and techniques in electronics engineering and covers topics ranging from basics to materials and components, devices, circuits, measurements, and applications. This edition is comprised of 27 chapters; the first of which presents general information on electronics engineering, including terminology, mathematical equations, mathematical signs and symbols, and Greek alphabet and symbols. Attention then turns to the history of electronics; electromagnetic and nuclear radiatio

  2. Practical microwave electron devices

    CERN Document Server

    Meurant, Gerard

    2013-01-01

    Practical Microwave Electron Devices provides an understanding of microwave electron devices and their applications. All areas of microwave electron devices are covered. These include microwave solid-state devices, including popular microwave transistors and both passive and active diodes; quantum electron devices; thermionic devices (including relativistic thermionic devices); and ferrimagnetic electron devices. The design of each of these devices is discussed as well as their applications, including oscillation, amplification, switching, modulation, demodulation, and parametric interactions.

  3. Neutrinos in the Electron

    International Nuclear Information System (INIS)

    Koschmieder, E. L.

    2007-01-01

    I will show that one half of the rest mass of the electron consists of electron neutrinos and that the other half of the rest mass of the electron consists of the mass in the energy of electric oscillations. With this composition we can explain the rest mass of the electron, its charge, its spin and its magnetic moment We have also determined the rest masses of the muon neutrino and the electron neutrino

  4. Electron-electron interactions in disordered systems

    CERN Document Server

    Efros, AL

    1985-01-01

    ``Electron-Electron Interactions in Disordered Systems'' deals with the interplay of disorder and the Coulomb interaction. Prominent experts give state-of-the-art reviews of the theoretical and experimental work in this field and make it clear that the interplay of the two effects is essential, especially in low-dimensional systems.

  5. VIRTUAL ELECTRONIC COMPONENTS OF THE ELECTRONIC EQUIPMENT

    Directory of Open Access Journals (Sweden)

    E. Lazarevich

    2013-01-01

    Full Text Available The article is present new idea of the creation, developments and improvements of the electronic equipment of complex systems by means of the virtual electronic components. The idea of the virtual electronic components is a presentation and perception of the creation and developments of the equipment on two forming: real – in the manner of standard marketed block of the intellectual property and image – in the manner of virtual component. The real component in most cases slows the development of the electronic equipment. The imaginary component is the «locomotive» of development of the electronic equipment. The Imaginary component contains the scientific has brushed against developer. The scientific has brushed against developer reveals of itself in the manner of virtual component on the modern level of the design rates of microelectronics.

  6. Practical XHV electron gun

    International Nuclear Information System (INIS)

    Urata, Tomohiro; Ishikawa, Tsuyoshi; Cho, Boklae; Oshima, Chuhei

    2008-01-01

    We have developed practical XHV chambers of a electron gun, of which the operating pressures are 1x10 -9 Pa in a stainless-steel one and 4x10 -9 Pa in a permalloy one. By mounting a noble single-atom electron source with high brightness and high spatial coherence on the electron gun including electron optics, we demonstrated highly collimated electron-beam emission: ∼80% of the total emission current entered the electron optics. This ratio was two or three orders of magnitude higher than those of the conventional electron sources. In XHV, in addition, we confirmed stable electron emission up to 20 nA, which results in the specimen current high enough for scanning electron microscopes. (author)

  7. A superconducting electron spectrometer

    International Nuclear Information System (INIS)

    Guttormsen, M.; Huebel, H.; Grumbkow, A. von

    1983-03-01

    The set-up and tests of an electron spectrometer for in-beam conversion electron measurements are described. A superconducting solenoid is used to transport the electrons from the target to cooled Si(Li) detectors. The solenoid is designed to produce either a homogeneous axially symmetric field of up to 2 Tesla or a variety of field profiles by powering the inner and outer set of coils of the solenoid separately. The electron trajectories resulting for various field profiles are discussed. In-beam electron spectra taken in coincidence with electrons, gammas and alpha-particles are shown. (Auth.)

  8. Electronics for dummies

    CERN Document Server

    Shamieh

    2015-01-01

    Explore the basic concepts of electronics, build your electronics workbench, and begin creating fun electronics projects right away! Electronics For Dummies, 3rd Edition is your guide to the world of electronics. Spanning circuitry, wiring, robotics, transmitters, amplifiers, and more, this book demystifies electricity basics and beyond. The third edition offers new content revised to reflect the latest advancements in the electronics field, and it offers full color project examples to spark your creativity and inspire you to put your new skills to use! Packed with projects that can be comple

  9. RHIC electron lenses upgrades

    Energy Technology Data Exchange (ETDEWEB)

    Gu, X. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Altinbas, Z. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Bruno, D. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Binello, S. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Costanzo, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Drees, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Gassner, D. M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Hock, J. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Hock, K. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Harvey, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Luo, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Marusic, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Mi, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Mernick, K. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Michnoff, R. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Miller, T. A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Pikin, A. I. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Robert-Demolaize, G. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Samms, T. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Shrey, T. C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Schoefer, V. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Tan, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Than, R. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Thieberger, P. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; White, S. M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2015-05-03

    In the Relativistic Heavy Ion Collider (RHIC) 100 GeV polarized proton run in 2015, two electron lenses were used to partially compensate for the head-on beam-beam effect for the first time. Here, we describe the design of the current electron lens, detailing the hardware modifications made after the 2014 commissioning run with heavy ions. A new electron gun with 15-mm diameter cathode is characterized. The electron beam transverse profile was measured using a YAG screen and fitted with a Gaussian distribution. During operation, the overlap of the electron and proton beams was achieved using the electron backscattering detector in conjunction with an automated orbit control program.

  10. Electron emitting filaments for electron discharge devices

    International Nuclear Information System (INIS)

    Leung, K.N.; Pincosy, P.A.; Ehlers, K.W.

    1988-01-01

    This patent describes an electron emitting device for use in an electron discharge system. It comprises: a filament having a pair of terminal ends, electrical supply means for supplying electrical power to the terminal ends of the filament for directly heating the filament by the passage of an electrical current along the filament between the terminal ends, the filament being substantially tapered in cross section continuously in one direction from one of its pair of terminal ends to another of its pair of terminal ends to achieve uniform heating of the filament along the length thereof by compensating for the nonuniform current along the filament due to the emission of electrons therefrom

  11. Narrow electron injector for ballistic electron spectroscopy

    International Nuclear Information System (INIS)

    Kast, M.; Pacher, C.; Strasser, G.; Gornik, E.

    2001-01-01

    A three-terminal hot electron transistor is used to measure the normal energy distribution of ballistic electrons generated by an electron injector utilizing an improved injector design. A triple barrier resonant tunneling diode with a rectangular transmission function acts as a narrow (1 meV) energy filter. An asymmetric energy distribution with its maximum on the high-energy side with a full width at half maximum of ΔE inj =10 meV is derived. [copyright] 2001 American Institute of Physics

  12. Electronic Submission of Labels

    Science.gov (United States)

    Pesticide registrants can provide draft and final labels to EPA electronically for our review as part of the pesticide registration process. The electronic submission of labels by registrants is voluntary but strongly encouraged.

  13. Electron scattering from pyrimidine

    International Nuclear Information System (INIS)

    Colmenares, Rafael; Fuss, Martina C; García, Gustavo; Oller, Juan C; Muñoz, Antonio; Blanco, Francisco; Almeida, Diogo; Limão-Vieira, Paulo

    2014-01-01

    Electron scattering from pyrimidine (C 4 H 4 N 2 ) was investigated over a wide range of energies. Following different experimental and theoretical approaches, total, elastic and ionization cross sections as well as electron energy loss distributions were obtained.

  14. THE ELECTRONIC SIGNATURE

    Directory of Open Access Journals (Sweden)

    Voiculescu Madalina Irena

    2009-05-01

    Full Text Available Article refers to significance and the digital signature in electronic commerce. Internet and electronic commerce open up many new opportunities for the consumer, yet, the security (or perceived lack of security of exchanging personal and financial data

  15. Laboratory Handbook Electronics

    CERN Multimedia

    1966-01-01

    Laboratory manual 1966 format A3 with the list of equipment cables, electronic tubes, chassis, diodes transistors etc. One of CERN's first material catalogue for construction components for mechanical and electronic chassis.

  16. Presidential Electronic Records Library

    Data.gov (United States)

    National Archives and Records Administration — PERL (Presidential Electronic Records Library) used to ingest and provide internal access to the Presidential electronic Records of the Reagan, Bush, and Clinton...

  17. Chapter 9: Electronics

    International Nuclear Information System (INIS)

    Grupen, Claus; Shwartz, Boris A.

    2006-01-01

    Sophisticated front-end electronics are a key part of practically all modern radiation detector systems. This chapter introduces the basic principles and their implementation. Topics include signal acquisition, electronic noise, pulse shaping (analog and digital), and data readout techniques

  18. Certified Electronics Recyclers

    Science.gov (United States)

    Learn how EPA encourages all electronics recyclers become certified by demonstrating to an accredited, independent third-party auditor and that they meet specific standards to safely recycle and manage electronics.

  19. Reversibly Bistable Flexible Electronics

    KAUST Repository

    Alfaraj, Nasir

    2015-01-01

    Introducing the notion of transformational silicon electronics has paved the way for integrating various applications with silicon-based, modern, high-performance electronic circuits that are mechanically flexible and optically semitransparent

  20. Electronic Signature Policy

    Science.gov (United States)

    Establishes the United States Environmental Protection Agency's approach to adopting electronic signature technology and best practices to ensure electronic signatures applied to official Agency documents are legally valid and enforceable

  1. Electronics Industry Study Report

    National Research Council Canada - National Science Library

    Belt, David; Fellows, John R; Kameru, Philip; Nazaroff, Boris-Frank A; Pauroso, Anthony; Schulz, Frederick; Ballew, Bob; Bond, Thomas; Demers, Stephy; Kirkpatrick, Steve

    2005-01-01

    This paper provides a national strategy for the US electronics industry. Electronics is one of the largest industries in the US and plays a critical role in almost every aspect of national security...

  2. Electron microscopy for Engineers

    International Nuclear Information System (INIS)

    Jones, I P

    2009-01-01

    This paper reviews the application of (mainly) Transmission Electron Microscopy (TEM) in an engineering context. The first two sections are TEM and chemical in nature; the final three sections are more general and include aspects of Scanning Electron Microscopy (SEM).

  3. ELSA electron stretcher devices

    International Nuclear Information System (INIS)

    1979-10-01

    The use of an electron stretcher ring at the Bonn electron synchrotron is discussed. The construction of the proposed ring is described, and the costs are estimated. Possible experiments using this ring are discussed. (HSI)

  4. Electron shuttles in biotechnology.

    Science.gov (United States)

    Watanabe, Kazuya; Manefield, Mike; Lee, Matthew; Kouzuma, Atsushi

    2009-12-01

    Electron-shuttling compounds (electron shuttles [ESs], or redox mediators) are essential components in intracellular electron transfer, while microbes also utilize self-produced and naturally present ESs for extracellular electron transfer. These compounds assist in microbial energy metabolism by facilitating electron transfer between microbes, from electron-donating substances to microbes, and/or from microbes to electron-accepting substances. Artificially supplemented ESs can create new routes of electron flow in the microbial energy metabolism, thereby opening up new possibilities for the application of microbes to biotechnology processes. Typical examples of such processes include halogenated-organics bioremediation, azo-dye decolorization, and microbial fuel cells. Herein we suggest that ESs can be applied widely to create new microbial biotechnology processes.

  5. Electronic Science Seminar

    Directory of Open Access Journals (Sweden)

    Geidarov P.Sh.

    2015-09-01

    Full Text Available The structure of electronic scientific seminar, which provides a high level of quality of the objectivity in the evaluation of scientific papers, including dissertations, is described. Conditions for the implementation of electronic scientific seminar are also considered.

  6. Copyright of Electronic Publishing.

    Science.gov (United States)

    Dong, Elaine; Wang, Bob

    2002-01-01

    Analyzes the importance of copyright, considers the main causes of copyright infringement in electronic publishing, discusses fair use of a copyrighted work, and suggests methods to safeguard copyrighted electronic publishing, including legislation, contracts, and technology. (Author/LRW)

  7. Paleoclassical electron heat transport

    International Nuclear Information System (INIS)

    Callen, J.D.

    2005-01-01

    Radial electron heat transport in low collisionality, magnetically-confined toroidal plasmas is shown to result from paleoclassical Coulomb collision processes (parallel electron heat conduction and magnetic field diffusion). In such plasmas the electron temperature equilibrates along magnetic field lines a long length L, which is the minimum of the electron collision length and a maximum effective half length of helical field lines. Thus, the diffusing field lines induce a radial electron heat diffusivity M ≅ L/(πR 0q ) ∼ 10 >> 1 times the magnetic field diffusivity η/μ 0 ≅ ν e (c/ω p ) 2 . The paleoclassical electron heat flux model provides interpretations for many features of 'anomalous' electron heat transport: magnitude and radial profile of electron heat diffusivity (in tokamaks, STs, and RFPs), Alcator scaling in high density plasmas, transport barriers around low order rational surfaces and near a separatrix, and a natural heat pinch (or minimum temperature gradient) heat flux form. (author)

  8. Extreme environment electronics

    CERN Document Server

    Cressler, John D

    2012-01-01

    Unfriendly to conventional electronic devices, circuits, and systems, extreme environments represent a serious challenge to designers and mission architects. The first truly comprehensive guide to this specialized field, Extreme Environment Electronics explains the essential aspects of designing and using devices, circuits, and electronic systems intended to operate in extreme environments, including across wide temperature ranges and in radiation-intense scenarios such as space. The Definitive Guide to Extreme Environment Electronics Featuring contributions by some of the world's foremost exp

  9. Electronic theodolite intersection systems

    OpenAIRE

    Bingley, R. M.

    1990-01-01

    The development of electronic surveying instruments, such as electronic theodolites, and concurrent advances in computer technology, has revolutionised engineering surveying; one of the more recent examples being the introduction of Electronic Theodolite Intersection Systems (ETISs). An ETIS consists of two or more electronic theodolites and a computer, with peripheral hardware and suitable software. The theoretical principles on which they are based have been known for a long time, but ...

  10. Electron-attachment processes

    International Nuclear Information System (INIS)

    Christophorou, L.G.; McCorkle, D.L.; Christodoulides, A.A.

    1982-01-01

    Topics covered include: (1) modes of production of negative ions, (2) techniques for the study of electron attachment processes, (3) dissociative electron attachment to ground-state molecules, (4) dissociative electron attachment to hot molecules (effects of temperature on dissociative electron attachment), (5) molecular parent negative ions, and (6) negative ions formed by ion-pair processes and by collisions of molecules with ground state and Rydberg atoms

  11. Handbook on electronic commerce

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, M. [Illinois Univ., Urbana, IL (United States). Beckman Inst. for Advanced Science and Technology; Blanning, R. [Vanderbilt Univ., Nashville, TN (United States). Owen Graduate School of Management; Strader, T. [Iowa State Univ., Ames, IA (United States). Management Information Systems; Whinston, A. [eds.] [Texas Univ., Austin, TX (United States). Dept. of Management Science and Information Systems

    2000-07-01

    The world is undergoing a revolution to a digital economy, with pronounced implications for corporate strategy, marketing, operations, information systems, customer services, global supply-chain management, and product distribution. This handbook examines the aspects of electronic commerce, including electronic storefront, on-line business, consumer interface, business-to-business networking, digital payment, legal issues, information product development, and electronic business models. Indispensable for academics, students and professionals who are interested in Electronic Commerce and Internet Business. (orig.)

  12. Electron Cyclotron Resonances in Electron Cloud Dynamics

    International Nuclear Information System (INIS)

    Celata, Christine; Celata, C.M.; Furman, Miguel A.; Vay, J.-L.; Yu, Jennifer W.

    2008-01-01

    We report a previously unknown resonance for electron cloud dynamics. The 2D simulation code 'POSINST' was used to study the electron cloud buildup at different z positions in the International Linear Collider positron damping ring wiggler. An electron equilibrium density enhancement of up to a factor of 3 was found at magnetic field values for which the bunch frequency is an integral multiple of the electron cyclotron frequency. At low magnetic fields the effects of the resonance are prominent, but when B exceeds ∼(2 pi mec/(elb)), with lb = bunch length, effects of the resonance disappear. Thus short bunches and low B fields are required for observing the effect. The reason for the B field dependence, an explanation of the dynamics, and the results of the 2D simulations and of a single-particle tracking code used to elucidate details of the dynamics are discussed

  13. Syringe injectable electronics

    Science.gov (United States)

    Hong, Guosong; Zhou, Tao; Jin, Lihua; Duvvuri, Madhavi; Jiang, Zhe; Kruskal, Peter; Xie, Chong; Suo, Zhigang; Fang, Ying; Lieber, Charles M.

    2015-01-01

    Seamless and minimally-invasive three-dimensional (3D) interpenetration of electronics within artificial or natural structures could allow for continuous monitoring and manipulation of their properties. Flexible electronics provide a means for conforming electronics to non-planar surfaces, yet targeted delivery of flexible electronics to internal regions remains difficult. Here, we overcome this challenge by demonstrating syringe injection and subsequent unfolding of submicrometer-thick, centimeter-scale macroporous mesh electronics through needles with a diameter as small as 100 micrometers. Our results show that electronic components can be injected into man-made and biological cavities, as well as dense gels and tissue, with > 90% device yield. We demonstrate several applications of syringe injectable electronics as a general approach for interpenetrating flexible electronics with 3D structures, including (i) monitoring of internal mechanical strains in polymer cavities, (ii) tight integration and low chronic immunoreactivity with several distinct regions of the brain, and (iii) in vivo multiplexed neural recording. Moreover, syringe injection enables delivery of flexible electronics through a rigid shell, delivery of large volume flexible electronics that can fill internal cavities and co-injection of electronics with other materials into host structures, opening up unique applications for flexible electronics. PMID:26053995

  14. Syringe-injectable electronics.

    Science.gov (United States)

    Liu, Jia; Fu, Tian-Ming; Cheng, Zengguang; Hong, Guosong; Zhou, Tao; Jin, Lihua; Duvvuri, Madhavi; Jiang, Zhe; Kruskal, Peter; Xie, Chong; Suo, Zhigang; Fang, Ying; Lieber, Charles M

    2015-07-01

    Seamless and minimally invasive three-dimensional interpenetration of electronics within artificial or natural structures could allow for continuous monitoring and manipulation of their properties. Flexible electronics provide a means for conforming electronics to non-planar surfaces, yet targeted delivery of flexible electronics to internal regions remains difficult. Here, we overcome this challenge by demonstrating the syringe injection (and subsequent unfolding) of sub-micrometre-thick, centimetre-scale macroporous mesh electronics through needles with a diameter as small as 100 μm. Our results show that electronic components can be injected into man-made and biological cavities, as well as dense gels and tissue, with >90% device yield. We demonstrate several applications of syringe-injectable electronics as a general approach for interpenetrating flexible electronics with three-dimensional structures, including (1) monitoring internal mechanical strains in polymer cavities, (2) tight integration and low chronic immunoreactivity with several distinct regions of the brain, and (3) in vivo multiplexed neural recording. Moreover, syringe injection enables the delivery of flexible electronics through a rigid shell, the delivery of large-volume flexible electronics that can fill internal cavities, and co-injection of electronics with other materials into host structures, opening up unique applications for flexible electronics.

  15. Electrons in Condensed Matter

    Indian Academy of Sciences (India)

    three freely moving electrons. The value at room temperature is 3.1 k B; the electronic specific heat is missing! The next stage in the electronic theory of solids clears up ..... a big dog? We do not know the reasons yet. As it turns out for many fundamentally interesting phenomena, colossal magneto- resistance may also find ...

  16. Arduino electronics blueprints

    CERN Document Server

    Wilcher, Don

    2015-01-01

    This book is intended for those who want to learn about electronics and coding by building amazing devices and gadgets with Arduino. If you are an experienced developer who understands the basics of electronics, then you can quickly learn how to build smart devices using Arduino. The only experience needed is a desire to learn about electronics, circuit breadboarding, and coding.

  17. EFFECTIVE ELECTRONIC TUTORIAL

    Directory of Open Access Journals (Sweden)

    Andrei A. Fedoseev

    2014-01-01

    Full Text Available The article analyzes effective electronic tutorials creation and application based on the theory of pedagogy. Herewith the issues of necessary electronic tutorial functional, ways of the educational process organization with the use of information and communication technologies and the logistics of electronic educational resources are touched upon. 

  18. Embracing Electronic Publishing.

    Science.gov (United States)

    Wills, Gordon

    1996-01-01

    Electronic publishing is the grandest revolution in the capture and dissemination of academic and professional knowledge since Caxton developed the printing press. This article examines electronic publishing, describes different electronic publishing scenarios (authors' cooperative, consolidator/retailer/agent oligopsony, publisher oligopoly), and…

  19. Soldering in electronics assembly

    CERN Document Server

    Judd, Mike

    2013-01-01

    Soldering in Electronics Assembly discusses several concerns in soldering of electronic assemblies. The book is comprised of nine chapters that tackle different areas in electronic assembly soldering. Chapter 1 discusses the soldering process itself, while Chapter 2 covers the electronic assemblies. Chapter 3 talks about solders and Chapter 4 deals with flux. The text also tackles the CS and SC soldering process. The cleaning of soldered assemblies, solder quality, and standards and specifications are also discussed. The book will be of great use to professionals who deal with electronic assem

  20. Quantitative secondary electron detection

    Science.gov (United States)

    Agrawal, Jyoti; Joy, David C.; Nayak, Subuhadarshi

    2018-05-08

    Quantitative Secondary Electron Detection (QSED) using the array of solid state devices (SSD) based electron-counters enable critical dimension metrology measurements in materials such as semiconductors, nanomaterials, and biological samples (FIG. 3). Methods and devices effect a quantitative detection of secondary electrons with the array of solid state detectors comprising a number of solid state detectors. An array senses the number of secondary electrons with a plurality of solid state detectors, counting the number of secondary electrons with a time to digital converter circuit in counter mode.

  1. Electron distribution function in electron-beam-excited plasmas

    International Nuclear Information System (INIS)

    Brau, C.A.

    1976-01-01

    In monatomic plasmas excited by high-intensity relativistic electron beams, the electron secondary distribution function is dominated by elastic electron-electron collisions at low electron energies and by inelastic electron-atom collisions at high electron energies (above the excitation threshold). Under these conditions, the total rate of excitation by inelastic collisions is limited by the rate at which electron-electron collisions relax the distribution function in the neighborhood of the excitation threshold. To describe this effect quantitatively, an approximate analytic solution of the electron Boltzmann equation is obtained, including both electron-electron and inelastic collisions. The result provides a simple formula for the total rate of excitation

  2. Molecular electron affinities

    International Nuclear Information System (INIS)

    Fukuda, E.K.

    1983-01-01

    Molecular electron affinities have historically been difficult quantities to measure accurately. These difficulties arise from differences in structure between the ion and neutral as well as the existence of excited negative ion states. To circumvent these problems, relative electron affinities were determined in this dissertation by studying equilibrium electron transfer reactions using a pulsed ion cyclotron resonance (ICR) spectrometer. Direct measurement of ion and neutral concentrations for reactions of the general type, A - + B = B - + A, allow calculation of the equilibrium constant and, therefore, the free energy change. The free energy difference is related to the difference in electron affinities between A and B. A relative electron affinity scale covering a range of about 45 kcal/mol was constructed with various substituted p-benzoquinones, nitrobenzenes, anhydrides, and benzophenones. To assign absolute electron affinities, various species with accurately known electron affinities are tied to the scale via ion-cyclotron double resonance bracketing techniques. After the relative scale is anchored to these species with well-known electron affinities, the scale is then used as a check on other electron affinity values as well as generating new electron affinity values. Many discrepancies were found between the electron affinities measured using the ICR technique and previous literature determinations

  3. Nonambipolar electron source

    International Nuclear Information System (INIS)

    Longmier, B.; Baalrud, S.; Hershkowitz, N.

    2006-01-01

    A radio frequency (rf) plasma-based electron source that does not rely on electron emission at a cathode surface has been constructed. All of the random electron flux incident on an exit aperture is extracted through an electron sheath resulting in total nonambipolar flow within the device when the ratio of the ion loss area to the electron loss area is approximately equal to the square root of the ratio of the ion mass to the electron mass, and the ion sheath potential drop at the chamber walls is much larger than T e /e. The nonambipolar electron source (NES) has an axisymmetric magnetic field of 100 G at the extraction aperture that results in a uniform plasma potential across the aperture, allowing the extraction of all the incident electron flux without the use of grids. A prototype NES has produced 15 A of continuous electron current, using 15 SCCM (SCCM denotes cubic centimeter per minute at STP) Ar, 1200 W rf power at 13.56 MHz, and 6 times gas utilization. Alternatively 8 A of electron current can be produced, using 3 SCCM Ar at 1200 W rf and 20 times gas utilization. NES could replace hollow cathode electron sources in a wide variety of applications

  4. High brightness electron accelerator

    International Nuclear Information System (INIS)

    Sheffield, R.L.; Carlsten, B.E.; Young, L.M.

    1994-01-01

    A compact high brightness linear accelerator is provided for use, e.g., in a free electron laser. The accelerator has a first plurality of accelerating cavities having end walls with four coupling slots for accelerating electrons to high velocities in the absence of quadrupole fields. A second plurality of cavities receives the high velocity electrons for further acceleration, where each of the second cavities has end walls with two coupling slots for acceleration in the absence of dipole fields. The accelerator also includes a first cavity with an extended length to provide for phase matching the electron beam along the accelerating cavities. A solenoid is provided about the photocathode that emits the electrons, where the solenoid is configured to provide a substantially uniform magnetic field over the photocathode surface to minimize emittance of the electrons as the electrons enter the first cavity. 5 figs

  5. Electronic equipment packaging technology

    CERN Document Server

    Ginsberg, Gerald L

    1992-01-01

    The last twenty years have seen major advances in the electronics industry. Perhaps the most significant aspect of these advances has been the significant role that electronic equipment plays in almost all product markets. Even though electronic equipment is used in a broad base of applications, many future applications have yet to be conceived. This versatility of electron­ ics has been brought about primarily by the significant advances that have been made in integrated circuit technology. The electronic product user is rarely aware of the integrated circuits within the equipment. However, the user is often very aware of the size, weight, mod­ ularity, maintainability, aesthetics, and human interface features of the product. In fact, these are aspects of the products that often are instrumental in deter­ mining its success or failure in the marketplace. Optimizing these and other product features is the primary role of Electronic Equipment Packaging Technology. As the electronics industry continues to pr...

  6. Automotive electronics design fundamentals

    CERN Document Server

    Zaman, Najamuz

    2015-01-01

    This book explains the topology behind automotive electronics architectures and examines how they can be profoundly augmented with embedded controllers. These controllers serve as the core building blocks of today’s vehicle electronics. Rather than simply teaching electrical basics, this unique resource focuses on the fundamental concepts of vehicle electronics architecture, and details the wide variety of Electronic Control Modules (ECMs) that enable the increasingly sophisticated "bells & whistles" of modern designs.  A must-have for automotive design engineers, technicians working in automotive electronics repair centers and students taking automotive electronics courses, this guide bridges the gap between academic instruction and industry practice with clear, concise advice on how to design and optimize automotive electronics with embedded controllers.

  7. Ion plasma electron gun

    International Nuclear Information System (INIS)

    Wakalopulos, G.

    1976-01-01

    In the disclosed electron gun positive ions generated by a hollow cathode plasma discharge in a first chamber are accelerated through control and shield grids into a second chamber containing a high voltage cold cathode. These positive ions bombard a surface of the cathode causing the cathode to emit secondary electrons which form an electron beam having a distribution adjacent to the cathode emissive surface substantially the same as the distribution of the ion beam impinging upon the cathode. After passing through the grids and the plasma discharge chamber, the electron beam exits from the electron gun via a foil window. Control of the generated electron beam is achieved by applying a relatively low control voltage between the control grid and the electron gun housing (which resides at ground potential) to control the density of the positive ions bombarding the cathode

  8. Seeing with electrons

    International Nuclear Information System (INIS)

    Nellist, P.

    2006-01-01

    Commercially available lens correctors are extending the reach of electron microscopes to unprecedented atomic scales, as Peter Nellist describes. The electron microscope was invented in 1933 and is based on the principle that electrons have a wavelength that is inversely proportional to their momentum. There are two basic types: transmission electron microscopes and scanning electron microscopes, plus a hybrid of the two. The lenses in an electron microscope are provided by electromagnetic fields, but they suffer from spherical aberration. The addition of octupole and quadrupole corrector fields has improved the resolution of the electron microscope to better than 0.1 nm in the last decade. The next step is to correct for chromatic aberration, after which the resolution of the microscope will probably be limited by the size of the atom itself. (U.K.)

  9. Engineered phages for electronics.

    Science.gov (United States)

    Cui, Yue

    2016-11-15

    Phages are traditionally widely studied in biology and chemistry. In recent years, engineered phages have attracted significant attentions for functionalization or construction of electronic devices, due to their specific binding, catalytic, nucleating or electronic properties. To apply the engineered phages in electronics, these are a number of interesting questions: how to engineer phages for electronics? How are the engineered phages characterized? How to assemble materials with engineered phages? How are the engineered phages micro or nanopatterned? What are the strategies to construct electronics devices with engineered phages? This review will highlight the early attempts to address these questions and explore the fundamental and practical aspects of engineered phages in electronics, including the approaches for selection or expression of specific peptides on phage coat proteins, characterization of engineered phages in electronics, assembly of electronic materials, patterning of engineered phages, and construction of electronic devices. It provides the methodologies and opens up ex-cit-ing op-por-tu-ni-ties for the development of a variety of new electronic materials and devices based on engineered phages for future applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Decal electronics for printed high performance cmos electronic systems

    KAUST Repository

    Hussain, Muhammad Mustafa; Sevilla, Galo Torres; Cordero, Marlon Diaz; Kutbee, Arwa T.

    2017-01-01

    High performance complementary metal oxide semiconductor (CMOS) electronics are critical for any full-fledged electronic system. However, state-of-the-art CMOS electronics are rigid and bulky making them unusable for flexible electronic applications

  11. Electronic Publishing or Electronic Information Handling?

    Science.gov (United States)

    Heck, A.

    The current dramatic evolution in information technology is bringing major modifications in the way scientists communicate. The concept of 'electronic publishing' is too restrictive and has often different, sometimes conflicting, interpretations. It is thus giving way to the broader notion of 'electronic information handling' encompassing the diverse types of information, the different media, as well as the various communication methodologies and technologies. New problems and challenges result also from this new information culture, especially on legal, ethical, and educational grounds. The procedures for validating 'published material' and for evaluating scientific activities will have to be adjusted too. 'Fluid' information is becoming a common concept. Electronic publishing cannot be conceived without link to knowledge bases nor without intelligent information retrieval tools.

  12. Electron transfer in proteins

    DEFF Research Database (Denmark)

    Farver, O; Pecht, I

    1991-01-01

    Electron migration between and within proteins is one of the most prevalent forms of biological energy conversion processes. Electron transfer reactions take place between active centers such as transition metal ions or organic cofactors over considerable distances at fast rates and with remarkable...... specificity. The electron transfer is attained through weak electronic interaction between the active sites, so that considerable research efforts are centered on resolving the factors that control the rates of long-distance electron transfer reactions in proteins. These factors include (in addition......-containing proteins. These proteins serve almost exclusively in electron transfer reactions, and as it turns out, their metal coordination sites are endowed with properties uniquely optimized for their function....

  13. Electrons in Nanostructures

    DEFF Research Database (Denmark)

    Flindt, Christian

    2007-01-01

    in the possibilities o®ered by the quantum mechanical behavior of electrons when it comes to informa- tion processing. This branch of research is also concerned with fundamental questions in physics. Besides an introduction to the above-mentioned subjects, the thesis con- tains a number of contributions to the ¯elds...... of coherent electron manip- ulation and the statistical description of electron transport through nano- devices. The physics of the electrons are described with a combination of numerical methods, developed and applied in the thesis, and more analytical approaches, which are also discussed. The thesis......-based communication. The statistical description of electron transport through nanostructures is based on rate equations, and the primary contribution of the thesis in that respect is the development of a method that allows for the calculation of the distribution of electrons passing through a device. The method...

  14. Transition to electronic publishing

    Science.gov (United States)

    Bowning, Sam

    Previous communications have described some of the many changes that will occur in the next few months as AGU makes the transition to fully electronic publishing. With the advent of the new AGU electronic publishing system, manuscripts will be submitted, edited, reviewed, and published in electronic formats. This piece discusses how the electronic journals will differ from the print journals. Electronic publishing will require some adjustments to the ways we currently think about journals from our perspective of standard print versions. Visiting the Web site of AGU's Geochemistry, Geophysics, Geosystems (G-Cubed) is a great way to get familiar with the look and feel of electronic publishing. However, protocols, especially for citations of articles, are still evolving. Some of the biggest changes for users of AGU publications may be the lack of page numbers, the use of a unique identifier (DOI),and changes in citation style.

  15. Electron microscopy of surfaces

    International Nuclear Information System (INIS)

    Venables, J.A.

    1981-01-01

    Electron beam techniques used to study clean surfaces and surface processes on a microscopic scale are reviewed. Recent experimental examples and possible future developments are discussed. Special emphasis is given to (i) transmission diffraction and microscopy techniques, including atomic imaging; (ii) Auger microscopy on bulk and thin film samples; (iii) secondary electron microscopy, especially low energy secondaries for work-function imaging and photoelectron imaging; and (iv) reflection electron microscopy and diffraction. (orig.)

  16. New electronics stuff chemistry

    International Nuclear Information System (INIS)

    Byeon, Su Il

    2003-04-01

    The first part of this book is about equilibrium electrochemistry on electric thermo dynamic equilibrium state of electrochemistry, crystal defect of solid, thermodynamics on defect electron and election in semiconductor, Gawani potential, volta potential and equilibrium potential and thermodynamics application in Gawani battery. The second part deals with dynamic electrochemistry electrode reaction kinetics and corrosion potential in normal state, diffusion and transport of ion and electron and current impedance spectroscopy. It also mentions industrial electrochemistry and laboratory works in electronics chemistry course.

  17. Ceramic Electron Multiplier

    International Nuclear Information System (INIS)

    Comby, G.

    1996-01-01

    The Ceramic Electron Multipliers (CEM) is a compact, robust, linear and fast multi-channel electron multiplier. The Multi Layer Ceramic Technique (MLCT) allows to build metallic dynodes inside a compact ceramic block. The activation of the metallic dynodes enhances their secondary electron emission (SEE). The CEM can be used in multi-channel photomultipliers, multi-channel light intensifiers, ion detection, spectroscopy, analysis of time of flight events, particle detection or Cherenkov imaging detectors. (auth)

  18. Organizing the Electronic Century

    OpenAIRE

    Richard N. Langlois

    2007-01-01

    This paper's title is an echo of Alfred Chandler's (2001) chronicle of the electronics industry, Inventing the Electronic Century. The paper attempts (A) a general reinterpretation of the pattern of technological advance in (American) electronics over the twentieth century and (B) a somewhat revisionist account of the role of organization and institution in that advance. The paper stresses the complex effects of product architecture and intellectual property regime on industrial organization ...

  19. Introduction to printed electronics

    CERN Document Server

    Suganuma, Katsuaki

    2014-01-01

    This book describes in detail modern technologies for printed electronics, explaining how nanotechnology and modern printing technology are merging to revolutionize electronics fabrication of thin, lightweight, large, and inexpensive products. Readers will benefit from the explanations of materials, devices and circuits used to design and implement the latest applications of printed electronics, such as thin flexible OLED displays, organic solar cells, OLED lighting, smart wallpaper, sensors, logic, memory and more.

  20. Interoperability for electronic ID

    OpenAIRE

    Zygadlo, Zuzanna

    2009-01-01

    Electronic Business, including eBanking, eCommerce and eGovernmental services, is today based on a large variety of security solutions, comprising electronic IDs provided by a broad community of Public Key Infrastructure (PKI) vendors. Significant differences in implementations of those solutions introduce a problem of lack of interoperability in electronic business, which have not yet been resolved by standardization and interoperability initiatives based on existing PKI trust models. It i...

  1. TRANSIENT ELECTRONICS CATEGORIZATION

    Science.gov (United States)

    2017-08-24

    AFRL-RY-WP-TR-2017-0169 TRANSIENT ELECTRONICS CATEGORIZATION Dr. Burhan Bayraktaroglu Devices for Sensing Branch Aerospace Components & Subsystems...SUBTITLE TRANSIENT ELECTRONICS CATEGORIZATION 5a. CONTRACT NUMBER In-house 5b. GRANT NUMBER N/A 5c. PROGRAM ELEMENT NUMBER N/A 6. AUTHOR(S) Dr. Burhan...88ABW-2017-3747, Clearance Date 31 July 2017. Paper contains color. 14. ABSTRACT Transient electronics is an emerging technology area that lacks proper

  2. Introduction to electronics

    CERN Document Server

    Korneff, Theodore

    1966-01-01

    Introduction to Electronics focuses on the study of electronics and electronic devices. Composed of 14 chapters, the book starts with discussions on dc circuits, including resistance, voltmeter, ammeter, galvanometer, internal resistance, and positive and negative currents. This topic is followed by discussions on ac circuits, particularly addressing voltage and current, average power, resistive load, complex plane, and parallel circuits. Discussions also focus on filters and tuned circuits, diodes, and power supplies. Particularly given attention are the processes, diagrams, and analyses

  3. Modern electronic materials

    CERN Document Server

    Watkins, John B

    2013-01-01

    Modern Electronic Materials focuses on the development of electronic components. The book first discusses the history of electronic components, including early developments up to 1900, developments up to World War II, post-war developments, and a comparison of present microelectric techniques. The text takes a look at resistive materials. Topics include resistor requirements, basic properties, evaporated film resistors, thick film resistors, and special resistors. The text examines dielectric materials. Considerations include basic properties, evaporated dielectric materials, ceramic dielectri

  4. Electron-beam lithography

    International Nuclear Information System (INIS)

    Harriott, L.; Liddle, A.

    1997-01-01

    As part of a commemorative series of articles to mark the hundredth anniversary of the discovery of the electron, this article describes the use of electron beams to write features on silicon wafers. Recent advances in electron beam lithography, as it is known, could enable this technology to be used for the mass manufacture of silicon chips. The validation of space-charge optimization and evaluation of printing techniques is underway. (UK)

  5. Electron beam lithography

    International Nuclear Information System (INIS)

    Harriott, L.; Liddle, A.

    1997-01-01

    As part of a commemorative series of articles to mark the hundredth anniversary of the discovery of the electron, this article describes the use of electron beams to write features on silicon wafers. Recent advances in electron beam lithography, as it is known, could enable this technology to be used for the mass manufacture of silicon chips. The validation of space-charge optimization and evaluation of printing techniques is underway. 5 figs

  6. Electron microscopy and diffraction

    International Nuclear Information System (INIS)

    Gjoennes, J.; Olsen, A.

    1986-01-01

    This report is a description of research activities and plans at the electron microscopy laboratorium, Physics Department, University of Oslo. Since the first electron microscope was installed in 1968, the research has covered inorganic structures, physical metallurgy, as well as theory of electron scattering and the development of methods in this field. The current plans involve efforts in the development of crystallographic and spectroscopic methods

  7. The Electronic Notebook Ontology

    OpenAIRE

    Chalk, Stuart

    2016-01-01

    Science is rapidly being brought into the electronic realm and electronic laboratory notebooks (ELN) are a big part of this activity. The representation of the scientific process in the context of an ELN is an important component to making the data recorded in ELNs semantically integrated. This presentation will outline initial developments of an Electronic Notebook Ontology (ENO) that will help tie together the ExptML ontology, HCLS Community Profile data descriptions, and the VIVO-ISF ontol...

  8. Electronics Environmental Benefits Calculator

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Electronics Environmental Benefits Calculator (EEBC) was developed to assist organizations in estimating the environmental benefits of greening their purchase,...

  9. Electronics circuits and systems

    CERN Document Server

    Bishop, Owen

    2007-01-01

    The material in Electronics - Circuits and Systems is a truly up-to-date textbook, with coverage carefully matched to the electronics units of the 2007 BTEC National Engineering and the latest AS and A Level specifications in Electronics from AQA, OCR and WJEC. The material has been organized with a logical learning progression, making it ideal for a wide range of pre-degree courses in electronics. The approach is student-centred and includes: numerous examples and activities; web research topics; Self Test features, highlighted key facts, formulae and definitions. Each chapter ends with a set

  10. High-power electronics

    CERN Document Server

    Kapitsa, Petr Leonidovich

    1966-01-01

    High-Power Electronics, Volume 2 presents the electronic processes in devices of the magnetron type and electromagnetic oscillations in different systems. This book explores the problems of electronic energetics.Organized into 11 chapters, this volume begins with an overview of the motion of electrons in a flat model of the magnetron, taking into account the in-phase wave and the reverse wave. This text then examines the processes of transmission of electromagnetic waves of various polarization and the wave reflection from grids made of periodically distributed infinite metal conductors. Other

  11. The auroral electron accelerator

    International Nuclear Information System (INIS)

    Bryant, D.A.; Hall, D.S.

    1989-01-01

    A model of the auroral electron acceleration process is presented in which the electrons are accelerated resonantly by lower-hybrid waves. The essentially stochastic acceleration process is approximated for the purposes of computation by a deterministic model involving an empirically derived energy transfer function. The empirical function, which is consistent with all that is known of electron energization by lower-hybrid waves, allows many, possibly all, observed features of the electron distribution to be reproduced. It is suggested that the process occurs widely in both space and laboratory plasmas. (author)

  12. Analytical Electron Microscope

    Data.gov (United States)

    Federal Laboratory Consortium — The Titan 80-300 is a transmission electron microscope (TEM) equipped with spectroscopic detectors to allow chemical, elemental, and other analytical measurements to...

  13. Two electron Rydberg states

    International Nuclear Information System (INIS)

    Cooke, W.E.

    1981-01-01

    This paper addresses the study of two-electron Rydberg atoms. With Multichannel Quantum Defect Theory (MQDT), there is a technique for characterizing a spectra in terms of a small number of parameters. A survey of some important effects specific to two-electon Rydberg states, using primarily the alkaline earth atoms for examples, is made. The remainder of the paper deals with a discussion of the electron-electron interaction, including some of the basic points of MQDT. Energy exchange between two electrons is also addressed

  14. Fundamentals of electronics

    CERN Document Server

    Schubert, Thomas F

    2015-01-01

    This book, Electronic Devices and Circuit Application, is the first of four books of a larger work, Fundamentals of Electronics. It is comprised of four chapters describing the basic operation of each of the four fundamental building blocks of modern electronics: operational amplifiers, semiconductor diodes, bipolar junction transistors, and field effect transistors. Attention is focused on the reader obtaining a clear understanding of each of the devices when it is operated in equilibrium. Ideas fundamental to the study of electronic circuits are also developed in the book at a basic level to

  15. Electronic signal conditioning

    CERN Document Server

    NEWBY, BRUCE

    1994-01-01

    At technician level, brief references to signal conditioning crop up in a fragmented way in various textbooks, but there has been no single textbook, until now!More advanced texts do exist but they are more mathematical and presuppose a higher level of understanding of electronics and statistics. Electronic Signal Conditioning is designed for HNC/D students and City & Guilds Electronics Servicing 2240 Parts 2 & 3. It will also be useful for BTEC National, Advanced GNVQ, A-level electronics and introductory courses at degree level.

  16. Electronics pocket book

    CERN Document Server

    Parr, E A

    1981-01-01

    Electronics Pocket Book, Fourth Edition is a nonmathematical presentation of the many varied topics covered by electronics. The book tackles electron physics, electronic components (i.e. resistors, capacitors, and conductors), integrated circuits, and the principles of a.c. and d.c. amplifiers. The text also discusses oscillators, digital circuits, digital computers, and optoelectronics (i.e., sensors, emitters, and devices that utilize light). Communications (such as line and radio communications, transmitters, receivers, and digital techniques); the principles and examples of servosystems; a

  17. Electron beam welding

    International Nuclear Information System (INIS)

    Schwartz, M.M.

    1974-01-01

    Electron-beam equipment is considered along with fixed and mobile electron-beam guns, questions of weld environment, medium and nonvacuum welding, weld-joint designs, tooling, the economics of electron-beam job shops, aspects of safety, quality assurance, and repair. The application of the process in the case of individual materials is discussed, giving attention to aluminum, beryllium, copper, niobium, magnesium, molybdenum, tantalum, titanium, metal alloys, superalloys, and various types of steel. Mechanical-property test results are examined along with the areas of application of electron-beam welding

  18. Flying Electronic Warfare Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Provides NP-3D aircraft host platforms for Effectiveness of Navy Electronic Warfare Systems (ENEWS) Program antiship missile (ASM) seeker simulators used...

  19. Free electron laser

    International Nuclear Information System (INIS)

    Ortega, J.M.; Billardon, M.

    1986-01-01

    Operation principle of a laser and an oscillator are recalled together with the klystron one. In the free electron laser, electrons go through an undulator or an optical klystron. Principles of the last one are given. The two distinct ways of producing coherent radiation with an undulator and an optical klystron are presented. The first one is the use of the free electron laser, the second is to make use of the spontaneous emission generation (harmonics generation). The different current types of free electron lasers are presented (Stanford, Los Alamos, Aco at Orsay). Prospects and applications are given in conclusion [fr

  20. Electronic circuits fundamentals & applications

    CERN Document Server

    Tooley, Mike

    2015-01-01

    Electronics explained in one volume, using both theoretical and practical applications.New chapter on Raspberry PiCompanion website contains free electronic tools to aid learning for students and a question bank for lecturersPractical investigations and questions within each chapter help reinforce learning Mike Tooley provides all the information required to get to grips with the fundamentals of electronics, detailing the underpinning knowledge necessary to appreciate the operation of a wide range of electronic circuits, including amplifiers, logic circuits, power supplies and oscillators. The

  1. Flexible Electronics Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Flexible Electronics Research Facility designs, synthesizes, tests, and fabricates materials and devices compatible with flexible substrates for Army information...

  2. Electronics circuits and systems

    CERN Document Server

    Bishop, Owen

    2011-01-01

    The material in Electronics - Circuits and Systems is a truly up-to-date textbook, with coverage carefully matched to the electronics units of the 2007 BTEC National Engineering and the latest AS and A Level specifications in Electronics from AQA, OCR and WJEC. The material has been organized with a logical learning progression, making it ideal for a wide range of pre-degree courses in electronics. The approach is student-centred and includes: numerous examples and activities; web research topics; Self Test features, highlighted key facts, formulae and definitions. Ea

  3. Reproductive biology of Bowdichia virgilioides Kunth (Fabaceae) = Biologia reprodutiva de Bowdichia virgilioides Kunth (Fabaceae)

    OpenAIRE

    André Luiz Gomes da Silva; Samyra Ramos Chaves; Jéfferson Mesquita Brito

    2011-01-01

    The aim of this study was to investigate the reproductive biology of Bowdichia virgilioides in an area of Cerrado (Brazilian Savanna). The study was carried out in Chapadinha, State of Maranhão in northeastern Brazil. Bowdichia virgilioides has cornucopia flowering and annual pattern. Flowering occurred at the beginning of the dry season, between June and August; and fruiting in the middle of this season, between July and October. The anthesis of B. virgilioides is diurnal, and the main flowe...

  4. Electrons in water radiolysis

    International Nuclear Information System (INIS)

    Laverne, J.A.; Pimblott, S.M.

    2006-01-01

    The hydrated electron is the main reducing species produced in the radiolysis of water. Many studies have examined its reactivity using pulsed radiolysis techniques and competition kinetics. Data bases list hundreds of rate coefficients for reaction of the hydrated electron with substances ranging from inorganic ions like nitrate to biopolymers like DNA. Although the chemistry of the hydrated electron is often examined, its mechanism of formation and variation in yield are considerable less known, especially under extreme conditions such as in high temperature water or with heavy ion radiolysis. This work will examine various aspects of the radiation chemistry of the hydrated electron beginning with the generation of secondary electrons in primary energy loss events during the passage of ionizing radiation to the radiolytic yields of the hydrated electron produced by different types of radiation. Ion radiation is a 'white light source.' Energy losses range from the minimum excitation energy of the medium up to the kinematic maximum determined by the collision parameters. However, certain energy loss events are more probable than others. The dipole oscillator strength distributions of media essentially give the probability of energy loss events in collisions with no momentum transfer. Dipole oscillator distributions have been constructed from experimental data for a wide variety of materials including all the phases of water. Calculations using cross sections based on dipole oscillator distributions show that the most probable energy loss event in water is only about 20 eV with an average value closer to 60 eV. The preponderance of energy loss events of less than 100 eV means that many low energy electrons are formed by the passage of a single ion. Low energy electrons have short mean free paths and they remain in the vicinity of the primary energy loss events. The spatial distribution of these low energy electrons defines the radial track structure of the incident

  5. INDRA. Electronic Architecture

    International Nuclear Information System (INIS)

    Ganil Team.

    1993-01-01

    The INDRA multidetector electronics is described. The system is a set of 17 rings consisting of 96 ionization chambers and 180 silicon detectors plus 324 cesium iodide and 12 Phoswich scintillators. Their integrated electronic lines, the trigger modules, the control and data acquisition units are presented briefly. (R.P.) 6 figs

  6. Recycling of electronic scrap

    DEFF Research Database (Denmark)

    Legarth, Jens Brøbech

    This Ph.D. thesis deals with the growingly important field of electronics recycling with special attention to the problem of printed circuit board recycling. A literature survey of contemporary electronics recycling and printed circuit board recycling is presented.Further, an analysis of the role...

  7. Cooling of electronic equipment

    DEFF Research Database (Denmark)

    A. Kristensen, Anders Schmidt

    2003-01-01

    Cooling of electronic equipment is studied. The design size of electronic equipment decrease causing the thermal density to increase. This affect the cooling which can cause for example failures of critical components due to overheating or thermal induced stresses. Initially a pin fin heat sink...

  8. Scanning electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Cox, B. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    1970-05-15

    The JSM-11 scanning electron microscope at CRNL has been used extensively for topographical studies of oxidized metals, fracture surfaces, entomological and biological specimens. A non-dispersive X-ray attachment permits the microanalysis of the surface features. Techniques for the production of electron channeling patterns have been developed. (author)

  9. Electron scattering from tetrahydrofuran

    International Nuclear Information System (INIS)

    Fuss, M C; Sanz, A G; García, G; Muñoz, A; Oller, J C; Blanco, F; Do, T P T; Brunger, M J; Almeida, D; Limão-Vieira, P

    2012-01-01

    Electron scattering from Tetrahydrofuran (C 4 H 8 O) was investigated over a wide range of energies. Following a mixed experimental and theoretical approach, total scattering, elastic scattering and ionization cross sections as well as electron energy loss distributions were obtained.

  10. Paradoxes of unstable electron

    International Nuclear Information System (INIS)

    Okun, L.B.; Zeldovich, Ya.B.

    1978-01-01

    The hypothesis that electron is unstable - when it is consistent with the vanishing mass of the photon- leads to a number of paradoxical statements. The lifetime of the electron is determined by emission of a huge number of longitudinal photons and exponentially depends on the amount of emitted energy. This suggests to discuss searches for charge nonconservation in experiments with high energy particles

  11. Electron scattering violates parity

    CERN Multimedia

    2004-01-01

    Parity violation has been observed in collisions between electrons at the Stanford Linear Accelerator Center (SLAC) in the US. The resuls, which are in agreement with the Stanford Model of particle physics, also provide a new measurement of the weak charge of the electron (½ page)

  12. Electronically Controlled Resistor Bank

    Science.gov (United States)

    Ross, Walter L.

    1987-01-01

    Resistance quickly varied in small steps over wide range. Device with no moving parts provides variable electrical resistance. Used with analog or digital circuity to provide electronic selection of large number of resistance values for testing, simulation, control, or other purposes. Nearest electromechanical equivalent of all-electronic device is potentiometer driven by servomotor.

  13. Voltmeter with Compton electrons

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, N R; Gorbics, S G; Weidenheimer, D M [Berkeley Research Associates, Springfield, VA (United States)

    1997-12-31

    A technique to measure the electron end point energy of bremsstrahlung in the MV regime using only two detectors is described. One of the detector measures the total radiation, the other filters out all except the hardest photons by looking only at their Compton electrons, whose average energy is determined with a magnetic field. (author). 4 figs., 2 refs.

  14. Advances in Opto Electronics

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Advances in Opto Electronics. Optoelectronics is where electronics was 15 years back. All Optical Amplifiers and Semiconductor Amplifiers. Fastest Semiconductor (InP) switch is at 170GHz- where is terrabit ? MEMS based switches that route traffic at wavelength level ...

  15. Electron beam welding

    International Nuclear Information System (INIS)

    Gabbay, M.

    1972-01-01

    The bead characteristics and the possible mechanisms of the electron beam penetration are presented. The different welding techniques are exposed and the main parts of an electron beam welding equipment are described. Some applications to nuclear, spatial and other industries are cited [fr

  16. Electron beam simulation applicators

    International Nuclear Information System (INIS)

    Purdy, J.A.

    1983-01-01

    A system for simulating electron beam treatment portals using low-temperature melting point alloy is described. Special frames having the same physical dimensions as the electron beam applicators used on the Varian Clinac 20 linear accelerator were designed and constructed

  17. Radiative electron capture

    International Nuclear Information System (INIS)

    Biggerstaff, J.A.; Appleton, B.R.; Datz, S.; Moak, C.D.; Neelavathi, V.N.; Noggle, T.S.; Ritchie, R.H.; VerBeek, H.

    1975-01-01

    Some data are presented for radiative electron capture by fast moving ions. The radiative electron capture spectrum is shown for O 8+ in Ag, along with the energy dependence of the capture cross-section. A discrepancy between earlier data, theoretical prediction, and the present data is pointed out. (3 figs) (U.S.)

  18. Electronics and Lithuanian Terminology

    Directory of Open Access Journals (Sweden)

    Stasys Zajankauskas

    2011-04-01

    Full Text Available It is found that the vacuum triode, transistor, monolithic circuit and microprocessor were the most important inventions of traditional electronics. Thus, the origins of the traditional electronics should be associated with the invention of the vacuum triode, but not with the invention of vacuum diode. It is shown that the science of electronics is not as young as computer science or up-to-date information technologies: electronics, including active electronics, had already celebrated the centenary, and the period of 2004–2008 is the period of numerous already solid jubilees. Thus, the terminology of electronics is not at initial stage of evolution as well – general terms should be already systematized and normalized. However, Lithuanian terms for electronic devices invented before tens of years and terms for old-defined notions associated with these devices are still varying, some are worsened. Especially, the incorrectly motivated terms used for variations of transistors and microcircuits are analyzed in the article. It is motivated which terms are preferable, systematic and exact. The paper is dedicated to the 50th anniversary of monolithic circuit, as well as the 60th anniversary of transistor, the 40th jubilee of microprocessor and centenary of electronics.

  19. Electron tunneling in chemistry

    International Nuclear Information System (INIS)

    Zamaraev, K.I.; Khajrutdinov, R.F.; Zhdanov, V.P.; Molin, Yu.N.

    1985-01-01

    Results of experimental and theoretical investigations are outlined systematically on electron tunnelling in chemical reactions. Mechanism of electron transport to great distances is shown to be characteristic to chemical compounds of a wide range. The function of tunnel reactions is discussed for various fields of chemistry, including radiation chemistry, electrochemistry, chemistry of solids, chemistry of surface and catalysis

  20. Managing electronic records

    CERN Document Server

    McLeod, Julie

    2005-01-01

    For records management courses, this book covers the theory and practice of managing electronic records as business and information assets. It focuses on the strategies, systems and procedures necessary to ensure that electronic records are appropriately created, captured, organized and retained over time to meet business and legal requirements.

  1. ELECTRON COOLING FOR RHIC

    International Nuclear Information System (INIS)

    BEN-ZVI, I.; AHRENS, L.; BRENNAN, M.; HARRISON, M.; KEWISCH, J.; MACKAY, W.; PEGGS, S.; ROSER, T.; SATOGATA, T.; TRBOJEVIC, D.; YAKIMENKO, V.

    2001-01-01

    We introduce plans for electron-cooling of the Relativistic Heavy Ion Collider (RHIC). This project has a number of new features as electron coolers go: It will cool 100 GeV/nucleon ions with 50 MeV electrons; it will be the first attempt to cool a collider at storage-energy; and it will be the first cooler to use a bunched beam and a linear accelerator as the electron source. The linac will be superconducting with energy recovery. The electron source will be based on a photocathode gun. The project is carried out by the Collider-Accelerator Department at BNL in collaboration with the Budker Institute of Nuclear Physics

  2. Electron - proton colliders

    International Nuclear Information System (INIS)

    Wiik, B.H.

    1985-01-01

    Electron-proton storage rings allow us to study the interaction between the two basic constituents of matter, electrons and quarks at very short distances. Such machines were first discussed in connection with the ISR but the idea was abandoned because of the anticipated low counting rate. The interest in electron-proton storage rings was rekindeled by the discovery of large pointlike cross sections in lepton-hardon interactions and several/sup 2-15/ projects have been discussed during the past decade. However, despite a glorious past, which includes the discovery of quarks and neutral currents, and a multitude of proposals no electron-proton storage ring has ever been built. What we might learn by studying electron-proton collisions at high energies is discussed. After some brief comments on present proposals the proposed DESY ep project HERA is described as an example of how to realize such a machine

  3. Electron: Cluster interactions

    International Nuclear Information System (INIS)

    Scheidemann, A.A.; Knight, W.D.

    1994-02-01

    Beam depletion spectroscopy has been used to measure absolute total inelastic electron-sodium cluster collision cross sections in the energy range from E ∼ 0.1 to E ∼ 6 eV. The investigation focused on the closed shell clusters Na 8 , Na 20 , Na 40 . The measured cross sections show an increase for the lowest collision energies where electron attachment is the primary scattering channel. The electron attachment cross section can be understood in terms of Langevin scattering, connecting this measurement with the polarizability of the cluster. For energies above the dissociation energy the measured electron-cluster cross section is energy independent, thus defining an electron-cluster interaction range. This interaction range increases with the cluster size

  4. Practical electronics for inventors

    CERN Document Server

    Scherz, Paul

    2013-01-01

    Spark your creativity and gain the electronics skills required to transform your innovative ideas into functioning gadgets. This hands-on, updated guide outlines electrical principles and provides thorough, easy-to-follow instructions, schematics, and illustrations. Findout how to select components, safely assemble circuits, perform error tests, and build plug-and-play prototypes. Practical Electronics for Inventors, Third Edition, features all-new chapters on sensors, microcontrollers, modular electronics, and the latest software tools. Coverage includes: Resistors, capacitors, inductors, and transformers Diodes, transistors, and integrated circuits Optoelectronics, solar cells, and phototransistors Sensors, GPS modules, and touch screens Op amps, regulators, and power supplies Digital electronics, LCD displays, and logic gates Microcontrollers and prototyping platforms, including Arduino DC motors, RC servos, and stepper motors Microphones, audio amps, and speakers Modular electronics and prototyping.

  5. Electronically cloaked nanoparticles

    Science.gov (United States)

    Shen, Wenqing

    The concept of electronic cloaking is to design objects invisible to conduction electrons. The approach of electronic cloaking has been recently suggested to design invisible nanoparticle dopants with electronic scattering cross section smaller than 1% of the physical cross section (pi a2), and therefore to enhance the carrier mobility of bulk materials. The proposed nanoparticles have core-shell structures. The dopants are incorporated inside the core, while the shell layer serves both as a spacer to separate the charge carriers from their parent atoms and as a cloaking shell to minimize the scattering cross section of the electrons from the ionized nanoparticles. Thermoelectric materials are usually highly doped to have enough carrier density. Using invisible dopants could achieve larger thermoelectric power factors by enhancing the electronic mobility. Core-shell nanoparticles show an advantage over one-layer nanoparticles, which are proposed in three-dimensional modulation doping. However designing such nanoparticles is not easy as there are too many parameters to be considered. This thesis first shows an approach to design hollow nanoparticles by applying constrains on variables. In the second part, a simple mapping approach is introduced where one can identify possible core-shell particles by comparing the dimensionless parameters of chosen materials with provided maps. In both parts of this work, several designs with realistic materials were made and proven to achieve electronic cloaking. Improvement in the thermoelectric power factor compared to the traditional impurity doping method was demonstrated in several cases.

  6. Electron Cooling of RHIC

    CERN Document Server

    Ben-Zvi, Ilan; Barton, Donald; Beavis, Dana; Blaskiewicz, Michael; Bluem, Hans; Brennan, Joseph M; Bruhwiler, David L; Burger, Al; Burov, Alexey; Burrill, Andrew; Calaga, Rama; Cameron, Peter; Chang, Xiangyun; Cole, Michael; Connolly, Roger; Delayen, Jean R; Derbenev, Yaroslav S; Eidelman, Yury I; Favale, Anthony; Fedotov, Alexei V; Fischer, Wolfram; Funk, L W; Gassner, David M; Hahn, Harald; Harrison, Michael; Hershcovitch, Ady; Holmes, Douglas; Hseuh Hsiao Chaun; Johnson, Peter; Kayran, Dmitry; Kewisch, Jorg; Kneisel, Peter; Koop, Ivan; Lambiase, Robert; Litvinenko, Vladimir N; MacKay, William W; Mahler, George; Malitsky, Nikolay; McIntyre, Gary; Meng, Wuzheng; Merminga, Lia; Meshkov, Igor; Mirabella, Kerry; Montag, Christoph; Nagaitsev, Sergei; Nehring, Thomas; Nicoletti, Tony; Oerter, Brian; Parkhomchuk, Vasily; Parzen, George; Pate, David; Phillips, Larry; Preble, Joseph P; Rank, Jim; Rao, Triveni; Rathke, John; Roser, Thomas; Russo, Thomas; Scaduto, Joseph; Schultheiss, Tom; Sekutowicz, Jacek; Shatunov, Yuri; Sidorin, Anatoly O; Skrinsky, Aleksander Nikolayevich; Smirnov, Alexander V; Smith, Kevin T; Todd, Alan M M; Trbojevic, Dejan; Troubnikov, Grigory; Wang, Gang; Wei, Jie; Williams, Neville; Wu, Kuo-Chen; Yakimenko, Vitaly; Zaltsman, Alex; Zhao, Yongxiang; ain, Animesh K

    2005-01-01

    We report progress on the R&D program for electron-cooling of the Relativistic Heavy Ion Collider (RHIC). This electron cooler is designed to cool 100 GeV/nucleon at storage energy using 54 MeV electrons. The electron source will be a superconducting RF photocathode gun. The accelerator will be a superconducting energy recovery linac. The frequency of the accelerator is set at 703.75 MHz. The maximum electron bunch frequency is 9.38 MHz, with bunch charge of 20 nC. The R&D program has the following components: The photoinjector and its photocathode, the superconducting linac cavity, start-to-end beam dynamics with magnetized electrons, electron cooling calculations including benchmarking experiments and development of a large superconducting solenoid. The photoinjector and linac cavity are being incorporated into an energy recovery linac aimed at demonstrating ampere class current at about 20 MeV. A Zeroth Order Design Report is in an advanced draft state, and can be found on the web at http://www.ags...

  7. Coherent electron cooling

    Energy Technology Data Exchange (ETDEWEB)

    Litvinenko,V.

    2009-05-04

    Cooling intense high-energy hadron beams remains a major challenge in modern accelerator physics. Synchrotron radiation is still too feeble, while the efficiency of two other cooling methods, stochastic and electron, falls rapidly either at high bunch intensities (i.e. stochastic of protons) or at high energies (e-cooling). In this talk a specific scheme of a unique cooling technique, Coherent Electron Cooling, will be discussed. The idea of coherent electron cooling using electron beam instabilities was suggested by Derbenev in the early 1980s, but the scheme presented in this talk, with cooling times under an hour for 7 TeV protons in the LHC, would be possible only with present-day accelerator technology. This talk will discuss the principles and the main limitations of the Coherent Electron Cooling process. The talk will describe the main system components, based on a high-gain free electron laser driven by an energy recovery linac, and will present some numerical examples for ions and protons in RHIC and the LHC and for electron-hadron options for these colliders. BNL plans a demonstration of the idea in the near future.

  8. Dose calculation for electrons

    International Nuclear Information System (INIS)

    Hirayama, Hideo

    1995-01-01

    The joint working group of ICRP/ICRU is advancing the works of reviewing the ICRP publication 51 by investigating the data related to radiation protection. In order to introduce the 1990 recommendation, it has been demanded to carry out calculation for neutrons, photons and electrons. As for electrons, EURADOS WG4 (Numerical Dosimetry) rearranged the data to be calculated at the meeting held in PTB Braunschweig in June, 1992, and the question and request were presented by Dr. J.L. Chartier, the responsible person, to the researchers who are likely to undertake electron transport Monte Carlo calculation. The author also has carried out the requested calculation as it was the good chance to do the mutual comparison among various computation codes regarding electron transport calculation. The content that the WG requested to calculate was the absorbed dose at depth d mm when parallel electron beam enters at angle α into flat plate phantoms of PMMA, water and ICRU4-element tissue, which were placed in vacuum. The calculation was carried out by the versatile electron-photon shower computation Monte Carlo code, EGS4. As the results, depth dose curves and the dependence of absorbed dose on electron energy, incident angle and material are reported. The subjects to be investigated are pointed out. (K.I.)

  9. Polarized electron sources

    International Nuclear Information System (INIS)

    Prepost, R.

    1994-01-01

    The fundamentals of polarized electron sources are described with particular application to the Stanford Linear Accelerator Center. The SLAC polarized electron source is based on the principle of polarized photoemission from Gallium Arsenide. Recent developments using epitaxially grown, strained Gallium Arsenide cathodes have made it possible to obtain electron polarization significantly in excess of the conventional 50% polarization limit. The basic principles for Gallium and Arsenide polarized photoemitters are reviewed, and the extension of the basic technique to strained cathode structures is described. Results from laboratory measurements of strained photocathodes as well as operational results from the SLAC polarized source are presented

  10. Electronic devices and circuits

    CERN Document Server

    Pridham, Gordon John

    1968-01-01

    Electronic Devices and Circuits, Volume 1 deals with the design and applications of electronic devices and circuits such as passive components, diodes, triodes and transistors, rectification and power supplies, amplifying circuits, electronic instruments, and oscillators. These topics are supported with introductory network theory and physics. This volume is comprised of nine chapters and begins by explaining the operation of resistive, inductive, and capacitive elements in direct and alternating current circuits. The theory for some of the expressions quoted in later chapters is presented. Th

  11. Electron collisions with biomolecules

    International Nuclear Information System (INIS)

    McKoy, V; Winstead, C

    2008-01-01

    We report on results of recent studies of collisions of low-energy electrons with nucleobases and other DNA constituents. A particular focus of these studies has been the identification and characterization of resonances that play a role in electron attachment leading to strand breaks in DNA. Comparison of the calculated resonance positions with results of electron transmission measurements is quite encouraging. However, the higher-lying π* resonances of the nucleobases appear to be of mixed elastic and core-excited character. Such resonant channel coupling raises the interesting possibility that the higher π*resonances in the nucleobases may promote dissociation of DNA by providing doorway states to triplet excited states.

  12. Field emission electronics

    CERN Document Server

    Egorov, Nikolay

    2017-01-01

    This book is dedicated to field emission electronics, a promising field at the interface between “classic” vacuum electronics and nanotechnology. In addition to theoretical models, it includes detailed descriptions of experimental and research techniques and production technologies for different types of field emitters based on various construction principles. It particularly focuses on research into and production of field cathodes and electron guns using recently developed nanomaterials and carbon nanotubes. Further, it discusses the applications of field emission cathodes in new technologies such as light sources, flat screens, microwave and X-ray devices.

  13. Quantum electronics basic theory

    CERN Document Server

    Fain, V M; Sanders, J H

    1969-01-01

    Quantum Electronics, Volume 1: Basic Theory is a condensed and generalized description of the many research and rapid progress done on the subject. It is translated from the Russian language. The volume describes the basic theory of quantum electronics, and shows how the concepts and equations followed in quantum electronics arise from the basic principles of theoretical physics. The book then briefly discusses the interaction of an electromagnetic field with matter. The text also covers the quantum theory of relaxation process when a quantum system approaches an equilibrium state, and explai

  14. Power Electronics for Microgrids

    DEFF Research Database (Denmark)

    Dragicevic, Tomislav; Blaabjerg, Frede

    2016-01-01

    A microgrid (MG) is a stand-alone or grid-connected hybrid renewable system that uses distributed renewable and nonrenewable energy sources and energy storage systems (ESSs) to supply power to local loads. The system is ordinarily based on power electronics, with interface converters allowing...... a continuous supply of power in the presence of variable RES production. This chapter describes some specific features of DC MGs in terms of power architecture, control, and protection. It also reviews several uncommon power electronic interfaces. Regarding control, operation without critical communication...... are explained in this chapter. The chapter concludes with a review of power electronic intensive protection solutions for DC MGs....

  15. Polarized electron sources

    Energy Technology Data Exchange (ETDEWEB)

    Prepost, R. [Univ. of Wisconsin, Madison, WI (United States)

    1994-12-01

    The fundamentals of polarized electron sources are described with particular application to the Stanford Linear Accelerator Center. The SLAC polarized electron source is based on the principle of polarized photoemission from Gallium Arsenide. Recent developments using epitaxially grown, strained Gallium Arsenide cathodes have made it possible to obtain electron polarization significantly in excess of the conventional 50% polarization limit. The basic principles for Gallium and Arsenide polarized photoemitters are reviewed, and the extension of the basic technique to strained cathode structures is described. Results from laboratory measurements of strained photocathodes as well as operational results from the SLAC polarized source are presented.

  16. BEPCII electronic logbook system

    International Nuclear Information System (INIS)

    Liu Shu; Zhao Jijiu; Wang Chunhong

    2007-01-01

    According to demands of BEPCII construction and future operation, we are going to supply an open electronic logbook platform for people to record their message in developing and running BEPCII, and browse the log-book on website. That gives people an open and transparent logbook, rather than traditional paper notebook. With the template of DESY's Elogbook, the BEPCII electronic logbook was developed, using the popular JSP technology to develop dynamic Web applications. This paper will introduce the development of BEPCII electronic logbook system. (authors)

  17. Electronic components and systems

    CERN Document Server

    Dennis, W H

    2013-01-01

    Electronic Components and Systems focuses on the principles and processes in the field of electronics and the integrated circuit. Covered in the book are basic aspects and physical fundamentals; different types of materials involved in the field; and passive and active electronic components such as capacitors, inductors, diodes, and transistors. Also covered in the book are topics such as the fabrication of semiconductors and integrated circuits; analog circuitry; digital logic technology; and microprocessors. The monograph is recommended for beginning electrical engineers who would like to kn

  18. A simple electron multiplexer

    International Nuclear Information System (INIS)

    Dobrzynski, L; Akjouj, A; Djafari-Rouhani, B; Al-Wahsh, H; Zielinski, P

    2003-01-01

    We present a simple multiplexing device made of two atomic chains coupled by two other transition metal atoms. We show that this simple atomic device can transfer electrons at a given energy from one wire to the other, leaving all other electron states unaffected. Closed-form relations between the transmission coefficients and the inter-atomic distances are given to optimize the desired directional electron ejection. Such devices can be adsorbed on insulating substrates and characterized by current surface technologies. (letter to the editor)

  19. Electron paramagnetic resonance

    CERN Document Server

    Al'tshuler, S A

    2013-01-01

    Electron Paramagnetic Resonance is a comprehensive text on the field of electron paramagnetic resonance, covering both the theoretical background and the results of experiment. This book is composed of eight chapters that cover theoretical materials and experimental data on ionic crystals, since these are the materials that have been most extensively studied by the methods of paramagnetic resonance. The opening chapters provide an introduction to the basic principles of electron paramagnetic resonance and the methods of its measurement. The next chapters are devoted to the theory of spectra an

  20. Semiconductor opto-electronics

    CERN Document Server

    Moss, TS; Ellis, B

    1972-01-01

    Semiconductor Opto-Electronics focuses on opto-electronics, covering the basic physical phenomena and device behavior that arise from the interaction between electromagnetic radiation and electrons in a solid. The first nine chapters of this book are devoted to theoretical topics, discussing the interaction of electromagnetic waves with solids, dispersion theory and absorption processes, magneto-optical effects, and non-linear phenomena. Theories of photo-effects and photo-detectors are treated in detail, including the theories of radiation generation and the behavior of semiconductor lasers a

  1. Auger electron spectroscopy

    International Nuclear Information System (INIS)

    Gopalaraman, C.P.

    1975-01-01

    General features of electron excited Auger electron spectroscopy (AES) which is a nondestructive technique for the analysis of surfaces upto about 15 Adeg depth with a detection limit of about 0.1% of a monolayer. Methods of measuring the Auger electron energies and recent improvements in the instrumentation are reviewed. Typical energy resolution is found to be about 0.5% which is specially suited for the detection of light elements. It is widely used in metallurgy, surface chemistry and thin film studies. (K.B.)

  2. Modern dictionary of electronics

    CERN Document Server

    Graf, Rudolf F

    1999-01-01

    Included in this fully revised classic are well over 28,000 terms, phrases, acronyms, and abbreviations from the ever-expanding worlds of consumer electronics, optics, microelectronics, computers, communications, and medical electronics. From the basic elements of theory to the most cutting-edge circuit technology, this book explains it all in both words and pictures.For easy reference, the author has provided definitions for standard abbreviations and equations as well as tables of SI (International System of Units) units, measurements, and schematic symbolsModern Dictionary of Electronics is

  3. VLSI electronics microstructure science

    CERN Document Server

    1982-01-01

    VLSI Electronics: Microstructure Science, Volume 4 reviews trends for the future of very large scale integration (VLSI) electronics and the scientific base that supports its development.This book discusses the silicon-on-insulator for VLSI and VHSIC, X-ray lithography, and transient response of electron transport in GaAs using the Monte Carlo method. The technology and manufacturing of high-density magnetic-bubble memories, metallic superlattices, challenge of education for VLSI, and impact of VLSI on medical signal processing are also elaborated. This text likewise covers the impact of VLSI t

  4. Single Electron Tunneling

    International Nuclear Information System (INIS)

    Ruggiero, Steven T.

    2005-01-01

    Financial support for this project has led to advances in the science of single-electron phenomena. Our group reported the first observation of the so-called ''Coulomb Staircase'', which was produced by tunneling into ultra-small metal particles. This work showed well-defined tunneling voltage steps of width e/C and height e/RC, demonstrating tunneling quantized on the single-electron level. This work was published in a now well-cited Physical Review Letter. Single-electron physics is now a major sub-field of condensed-matter physics, and fundamental work in the area continues to be conducted by tunneling in ultra-small metal particles. In addition, there are now single-electron transistors that add a controlling gate to modulate the charge on ultra-small photolithographically defined capacitive elements. Single-electron transistors are now at the heart of at least one experimental quantum-computer element, and single-electron transistor pumps may soon be used to define fundamental quantities such as the farad (capacitance) and the ampere (current). Novel computer technology based on single-electron quantum dots is also being developed. In related work, our group played the leading role in the explanation of experimental results observed during the initial phases of tunneling experiments with the high-temperature superconductors. When so-called ''multiple-gap'' tunneling was reported, the phenomenon was correctly identified by our group as single-electron tunneling in small grains in the material. The main focus throughout this project has been to explore single electron phenomena both in traditional tunneling formats of the type metal/insulator/particles/insulator/metal and using scanning tunneling microscopy to probe few-particle systems. This has been done under varying conditions of temperature, applied magnetic field, and with different materials systems. These have included metals, semi-metals, and superconductors. Amongst a number of results, we have

  5. Consulting in Electronic Commerce

    Directory of Open Access Journals (Sweden)

    Florentina Loredana Tache

    2010-10-01

    Full Text Available Economic development of electronic services provide advice and many agents of existingreferral systems to recommend and provide products, information and customized views of thecommunity through a personalized interaction in real time. Distributed systems of autonomous agentsare becoming increasingly important in electronic comet because the basic decisions of agents adviceon trust and reputation are taken in a similar way human society. If these decisions will be as a realconsumer protection, when new aspects of online consumer legislation will become usefulinformation in advice and consulting of electronic commerce.

  6. Coding for Electronic Mail

    Science.gov (United States)

    Rice, R. F.; Lee, J. J.

    1986-01-01

    Scheme for coding facsimile messages promises to reduce data transmission requirements to one-tenth current level. Coding scheme paves way for true electronic mail in which handwritten, typed, or printed messages or diagrams sent virtually instantaneously - between buildings or between continents. Scheme, called Universal System for Efficient Electronic Mail (USEEM), uses unsupervised character recognition and adaptive noiseless coding of text. Image quality of resulting delivered messages improved over messages transmitted by conventional coding. Coding scheme compatible with direct-entry electronic mail as well as facsimile reproduction. Text transmitted in this scheme automatically translated to word-processor form.

  7. The art of electronics

    CERN Document Server

    Horowitz, Paul

    2015-01-01

    At long last, here is the thoroughly revised and updated third edition of the hugely successful Art of Electronics. It is widely accepted as the best single authoritative book on electronic circuit design. In addition to new or enhanced coverage of many topics, the Third Edition includes: 90 oscilloscope screenshots illustrating the behavior of working circuits; dozens of graphs giving highly useful measured data of the sort that's often buried or omitted in datasheets but which you need when designing circuits; 80 tables (listing some 1650 active components), enabling intelligent choice of circuit components by listing essential characteristics (both specified and measured) of available parts. The new Art of Electronics ​​retains the feeling of informality and easy access that helped make the earlier editions so successful and popular. It is an indispensable reference and the gold standard​​ for anyone, student or researcher, professional or amateur, who works with electronic circuits.

  8. Electron and Photon ID

    CERN Document Server

    Hryn'ova, Tetiana; The ATLAS collaboration

    2017-01-01

    The identification of prompt photons and the rejection of background coming mostly from photons from hadron decays relies on the high granularity of the ATLAS calorimeter. The electron identification used in ATLAS for run 2 is based on a likelihood discrimination to separate isolated electron candidates from candidates originating from photon conversions, hadron misidentification and heavy flavor decays. In addition, isolation variables are used as further handles to separate signal and background. Several methods are used to measure with data the efficiency of the photon identification requirements, to cover a broad energy spectrum. At low energy, photons from radiative Z decays are used. In the medium energy range, similarities between electrons and photon showers are exploited using Z->ee decays. At high energy, inclusive photon samples are used. The measurement of the efficiencies of the electron identification and isolation cuts are performed with the data using tag and probe techniques with large statis...

  9. Channel electron multipliers

    International Nuclear Information System (INIS)

    Seidman, A.; Avrahami, Z.; Sheinfux, B.; Grinberg, J.

    1976-01-01

    A channel electron multiplier is described having a tubular wall coated with a secondary-electron emitting material and including an electric field for accelerating the electrons, the electric field comprising a plurality of low-resistive conductive rings each alternating with a high-resistive insulating ring. The thickness of the low-resistive rings is many times larger than that of the high-resistive rings, being in the order of tens of microns for the low-resistive rings and at least one order of magnitude lower for the high-resistive rings; and the diameter of the channel tubular walls is also many times larger than the thickness of the high-resistive rings. Both single-channel and multiple-channel electron multipliers are described. A very important advantage, particularly in making multiple-channel multipliers, is the simplicity of the procedure that may be used in constructing such multipliers. Other operational advantages are described

  10. Typewriting by Electronics

    Science.gov (United States)

    Etier, Faborn

    1971-01-01

    By using the electronic typewriting teaching aid, it is believed by those closely associated with its use in teaching typing that as much can be accomplished in one semester as in two semesters using the conventional method of teaching. (Editor)

  11. Electron identification at CDF

    International Nuclear Information System (INIS)

    Kim, Shinhong

    1990-01-01

    Electron identification at CDF is performed using the information of lateral and longitudinal shower spread, the track-cluster position match and the energy-momentum match. The tracking chamber with a solenoidal magnetic field at CDF is powerful for rejecting the backgrounds such as the π ± - π 0 overlaps, the π 0 /γ conversions and interactive π ± in electromagnetic calorimeter: The energy- momentum match cut can decrease the background due to the π ± - π 0 overlaps for non-isolated electrons with Et above 10 GeV by a factor of 20. The conversion electrons are identified using track information with an efficiency of 80 ± 3%. The charge of electrons from W decay can be determined in the pseudorapidity range of |η| < 1.7 at CDF. The charge determination is useful for background estimation of Drell-Yan physics and heavy flavor physics. 5 refs., 5 figs

  12. The electron accelerator Ridgetron

    International Nuclear Information System (INIS)

    Hayashizaki, N.; Hattori, T.; Odera, M.; Fujisawa, T.

    1999-01-01

    Many electron accelerators of DC or RF type have been widely used for electron beam irradiation (curing, crosslinking of polymers, sterilization of medical disposables, preservation of food, etc.). Regardless of the acceleration energy, the accelerators to be installed in industrial facilities, have to satisfy the requires of compact size, low power consumption and stable operation. The DC accelerator is realized very compact in the energy under 300 keV, however, it is large to prevent the discharge of an acceleration column in the energy over 300 keV. The RF electron accelerator Ridgetron has been developed to accelerate the continuous beam of the 0.5-10 MeV range in compact space. It is the first example as an electron accelerator incorporated a ridged RF cavity. A prototype system of final energy of 2.5 MeV has been studied to confirm the feasibility at present

  13. Advanced Electron Linacs

    Energy Technology Data Exchange (ETDEWEB)

    Siemann, R.

    2005-02-14

    The research into advanced acceleration concepts for electron linear accelerators being pursued at SLAC is reviewed. This research includes experiments in laser acceleration, plasma wakefield acceleration, and mmwavelength RF driven accelerators.

  14. Electronic Universal Vote

    Directory of Open Access Journals (Sweden)

    Cristian USCATU

    2008-01-01

    Full Text Available In the days of informational society everything is going online. Most aspects of our lives have online components. Since democracy is a big issue, it could not escape this trend. Governments themselves are moving to the online environment for the purpose of improving their internal efficiency and their availability to the citizens, businesses and other parties interested. Since governments are the result of elections, elections have also been touched by the electronic fever. New electronic voting solutions arise and each one brings new debates with many arguments in their favor and against them. Accessibility and ease of use leads the arguments in favor of electronic voting over the internet, while fear of fraud is the main reason people are avoiding electronics and clinging on classic paper ballots.

  15. ORELA electron guns

    International Nuclear Information System (INIS)

    Christian, O.W.; Lewis, T.A.

    1981-09-01

    The most recent information concerning the production and performance of ORELA electron guns is presented. Included are descriptions of procedures for gun fabrication, cathode conditioning and high voltage processing. Highlights of the performance characteristics are also included

  16. Corrosion in Electronics

    DEFF Research Database (Denmark)

    Ambat, Rajan; Gudla, Helene Virginie Conseil; Verdingovas, Vadimas

    2017-01-01

    Electronic control units, power modules, and consumer electronics are used today in a wide variety of varying climatic conditions. Varying external climatic conditions of temperature and humidity can cause an uncontrolled local climate inside the device enclosure. Uncontrolled humidity together...... and high density packing combined with the use of several materials, which can undergo electrochemical corrosion in the presence of water film formed due to humidity exposure and bias conditions on the PCBA surface. This article provides a short review of the corrosion reliability issues of electronics due...... to the use of electronics under varying humidity conditions. Important PCBA aspects, which are fundamental to the corrosion cell formation under humid conditions, are discussed. Effect of hygroscopic residues from the process and service and their role in assisting water film build up and corrosion...

  17. Paper based electronics platform

    KAUST Repository

    Nassar, Joanna Mohammad; Sevilla, Galo Andres Torres; Hussain, Muhammad Mustafa

    2017-01-01

    A flexible and non-functionalized low cost paper-based electronic system platform fabricated from common paper, such as paper based sensors, and methods of producing paper based sensors, and methods of sensing using the paper based sensors

  18. Electronic personal dosemeters

    International Nuclear Information System (INIS)

    Marshall, T.O.; Bartlett, D.T.; Burgess, P.H.; Cranston, C.S.; Higginbottom, D.J.; Sutton, K.W.

    1990-01-01

    Personal dosimetry services approved by their national authorities for category A workers, invariably use passive dosemeters incorporating photographic film or thermoluminescent detectors. However, the performance characteristics of electronic dosemeters has improved substantially over the past decade to such an extent that in the opening lecture of the Solid State Dosimetry Conference at Oxford in 1986 the development of an electronic 'smart card' based on a silicon detector was briefly discussed. This idea has been taken up and at least one development programme is in progress aimed at the production of an electronic dosemeter suitable for use as a legal device. The more important performance requirements of personal dosemeters for this purpose are discussed and the earlier electronic dosemeter designs and the latest devices under development to meet this specification are compared. (author)

  19. Scanning Auger Electron Microscope

    Data.gov (United States)

    Federal Laboratory Consortium — A JEOL model 7830F field emission source, scanning Auger microscope.Specifications / Capabilities:Ultra-high vacuum (UHV), electron gun range from 0.1 kV to 25 kV,...

  20. Issues in Electronic Publishing.

    Science.gov (United States)

    Meadow, Charles T.

    1997-01-01

    Discusses issues related to electronic publishing. Topics include writing; reading; production, distribution, and commerce; copyright and ownership of intellectual property; archival storage; technical obsolescence; control of content; equality of access; and cultural changes. (Author/LRW)

  1. Modular Lego-Electronics

    KAUST Repository

    Shaikh, Sohail F.; Ghoneim, Mohamed T.; Bahabry, Rabab R.; Khan, Sherjeel M.; Hussain, Muhammad Mustafa

    2017-01-01

    . Here, a generic manufacturable method of converting state-of-the-art complementary metal oxide semiconductor-based ICs into modular Lego-electronics is shown with unique geometry that is physically identifiable to ease manufacturing and enhance

  2. Electron linac injector developments

    International Nuclear Information System (INIS)

    Fraser, J.S.

    1986-01-01

    There is a continuing demand for improved injectors for electron linacs. Free-electron laser (FEL) oscillators require pulse trains of high brightness and, in some applications, high average power at the same time. Wakefield-accelerator and laser-acceleration experiments require isolated bunches of high peak brightness. Experiments with alkali-halide photoemissive and thermionic electron sources in rf cavities for injector applications are described. For isolated pulses, metal photocathodes (illuminated by intense laser pulses) are being employed. Reduced emittance growth in high-peak-current electron injectors may be achieved by linearizing the cavity electric field's radial component and by using high field strengths at the expense of lower shunt impedance. Harmonically excited cavities have been proposed for enlarging the phase acceptance of linac cavities and thereby reducing the energy spread produced in the acceleration process. Operation of injector linacs at a subharmonic of the main linac frequency is also proposed for enlarging the phase acceptance

  3. Electronics for guitarists

    CERN Document Server

    Dailey, Denton J

    2014-01-01

    Electronics for Guitarists focuses on analog circuitry, and is written for the guitarist interested in transistor and vacuum tube-based amplifiers. Topics include discrete transistors and diodes, classical filter circuits, and vacuum tube-based amplifiers.

  4. Nemo-3 calorimeter electronics

    International Nuclear Information System (INIS)

    Bernaudin, P.; Cheikali, C.; Lavigne, B.; Richard, A.; Lebris, J.

    2000-11-01

    The calorimeter electronics of the NEMO-3 double beta decay experiment fulfills three functions: -energy measurement of the electrons by measuring the charge of the pulses, - time measurement, - fast first level triggering. The electronics of the 1940 Scintillator-PM modules is implemented as 40 '9U x 400 mm VME' boards of up to 51 channels. For each channel the analog signals conditioning is implemented as one SMD daughter board. Each board performs 12 bit charge measurements with 0.35 pC charge resolution, 12 bit time measurements with 50 ps time resolution and a fast analog multiplicity level for triggering. The total handling and conversion time for all the channels is less than 100 μs. The electronics will be presented as well as the test system. (authors)

  5. Novel electron gas systems

    International Nuclear Information System (INIS)

    Senatore, G.; Rapisarda, F.; Conti, S.

    1998-01-01

    We review recent progress on the physics of electrons in the bilayered electron gas, relevant to coupled quantum wells in GaAs/AIGaAs heterostructures. First we focus on the phase diagram of a symmetric bilayer at T = B = 0, obtained by diffusion Monte Carlo (DMC) simulations. It is found that inter-layer correlations stabilize crystalline structures at intermediate inter-layer separation, while favoring a liquid phase at smaller distance. Also, the available DMC evidence is in contrast with the recently (Hartree-Fock) predicted total charge transfer (TCT), whereby all the electron spontaneously jump in one layer. In fact, one can show that such a TCT state is never stable in the ideal bilayer with no tunneling. We finally comment on ongoing DMC investigations on the electron-hole bilayer, where excitonic condensation is expected to take place. (Copyright (1998) World Scientific Publishing Co. Pte. Ltd)

  6. Improved electron transport layer

    DEFF Research Database (Denmark)

    2012-01-01

    The present invention provides: a method of preparing a coating ink for forming a zinc oxide electron transport layer, comprising mixing zinc acetate and a wetting agent in water or methanol; a coating ink comprising zinc acetate and a wetting agent in aqueous solution or methanolic solution......; a method of preparing a zinc oxide electron transporting layer, which method comprises: i) coating a substrate with the coating ink of the present invention to form a film; ii) drying the film; and iii) heating the dry film to convert the zinc acetate substantially to ZnO; a method of preparing an organic...... photovoltaic device or an organic LED having a zinc oxide electron transport layer, the method comprising, in this order: a) providing a substrate bearing a first electrode layer; b) forming an electron transport layer according to the following method: i) coating a coating ink comprising an ink according...

  7. Magnetic electron scattering

    International Nuclear Information System (INIS)

    Peterson, G.A.

    1989-01-01

    We briefly review some of the motivations, early results, and techniques of magnetic elastic and inelastic electron-nucleus scattering. We then discuss recent results, especially those acquired at high momentum transfers. 50 refs., 19 figs

  8. Advances in electron dosimetry

    International Nuclear Information System (INIS)

    Harder, D.

    1980-04-01

    Starting from the two most important interactions of electrons with matter, energy loss and scattering, a review is given of a number of effects which are important in electron dosimetry. For determining the absorbed dose in a phantom by means of ionization chambers, imformation is required on the electron spectrum at the location of the measurement, on the stopping powers of different materials and on disturbances such as the displacement of the effective point of measurements from the centre of the chamber. By means of figures and photographs of electron traces in bubble chambers, the origin of the formation of the absorbed dose maximum in a phantom is explained. It is shown, how by multiple scattering, the similarity of dose distributions in different media can be explained and how by Monte-Carlo calculations absorbed dose distributions in the surroundings of inhomogeneities (e.g. cavities) in a phantom can be determined. (orig.) [de

  9. Electron gun for SSRF

    International Nuclear Information System (INIS)

    Sheng Shugang; Lin Guoqiang; Gu Qiang; Li Deming

    2003-01-01

    A 100 kV triode-electron-gun has been designed and manufactured for the Linac of Shanghai Synchrotron Radiation Facility (SSRF). In this paper the performance of the gun and some key components are described

  10. PREFACE: Spin Electronics

    Science.gov (United States)

    Dieny, B.; Sousa, R.; Prejbeanu, L.

    2007-04-01

    Conventional electronics has in the past ignored the spin on the electron, however things began to change in 1988 with the discovery of giant magnetoresistance in metallic thin film stacks which led to the development of a new research area, so called spin-electronics. In the last 10 years, spin-electronics has achieved a number of breakthroughs from the point of view of both basic science and application. Materials research has led to several major discoveries: very large tunnel magnetoresistance effects in tunnel junctions with crystalline barriers due to a new spin-filtering mechanism associated with the spin-dependent symmetry of the electron wave functions new magnetic tunnelling barriers leading to spin-dependent tunnelling barrier heights and acting as spin-filters magnetic semiconductors with increasingly high ordering temperature. New phenomena have been predicted and observed: the possibility of acting on the magnetization of a magnetic nanostructure with a spin-polarized current. This effect, due to a transfer of angular momentum between the spin polarized conduction electrons and the local magnetization, can be viewed as the reciprocal of giant or tunnel magnetoresistance. It can be used to switch the magnetization of a magnetic nanostructure or to generate steady magnetic excitations in the system. the possibility of generating and manipulating spin current without charge current by creating non-equilibrium local accumulation of spin up or spin down electrons. The range of applications of spin electronics materials and phenomena is expanding: the first devices based on giant magnetoresistance were the magnetoresistive read-heads for computer disk drives. These heads, introduced in 1998 with current-in plane spin-valves, have evolved towards low resistance tunnel magnetoresistice heads in 2005. Besides magnetic recording technology, these very sensitive magnetoresistive sensors are finding applications in other areas, in particular in biology. magnetic

  11. ELECTRONIC BANKING AND ELECTRONIC COMMERCE IN SERBIA

    Directory of Open Access Journals (Sweden)

    Ivana B. Petrevska

    2014-10-01

    Full Text Available Nowadays, we may witness to dramatic and visible changes in our life environment. Business ambient for companies is different every day, and it is very hard to predict a direction of future changes. There is an environment characterized by sharp competition and increasing number of competitors, fast technological improvements and highly sophisticated and informed costumers. Technological process influences the humanity strongly, changing the way that people live, work and spend. Electronic commerce and electronic banking has become incontinent, and makes a great part of today's total transactions. There are an increasing number of companies that perform their business that way and make profit. Social networks are proven to be the least expensive way of information exchange, and they are present in almost every part of the world. The globalization has reached the most distant parts of the Earth. Every resistance to new technologies is dangerous and may lead to bankruptcy. Due to the EU expansion, Internet users are to be expected, and prosperity of the e-commerce business models at the same time. In Serbia, electronic commerce is present, but not as developed as in EU countries. E-commerce, however it might be successful throughout the world, it is somewhat slow in its growth in Serbia. The reasons are numerous, and main obstacles are the lack of trust, still limited usage of banking cards, avoiding of e-payments by older population etc. Also, the recent scandals over the misuse of personal data, and e-crime are discouraging factors for the growth of e-trade and ebanking. The younger generations are ever more ready to use e-commerce, since they are open to new technologies and do not have the defensive attitude towards it. E-commerce and e-banking has growing potential even among older population, if the society prevents them from fear and mistrust.

  12. Thermionics basic principles of electronics

    CERN Document Server

    Jenkins, J; Ashhurst, W

    2013-01-01

    Basic Principles of Electronics, Volume I : Thermionics serves as a textbook for students in physics. It focuses on thermionic devices. The book covers topics on electron dynamics, electron emission, and the themionic vacuum diode and triode. Power amplifiers, oscillators, and electronic measuring equipment are studied as well. The text will be of great use to physics and electronics students, and inventors.

  13. Low emittance thermionic electron guns

    International Nuclear Information System (INIS)

    Herrmannsfeldt, W.B.

    1989-01-01

    The author discusses self-field effects and external field effects for electron guns. He also discusses designs of electron guns and their uses in electron cooling systems and as an injector for electrostatic free electron lasers. He closes by looking at electron guns for linear accelerators. 20 references, 3 figures

  14. A new stage of nuclear electronics-particle electronics

    International Nuclear Information System (INIS)

    Xi Deming

    1987-01-01

    The rapid development of high energy physics experiments has pushed the nuclear electronics to a new stage, i.e. the particle electronics. In this paper the background, main features and recent trends of the particle electronics are expounded

  15. Electron attachment cross sections obtained from electron attachment spectroscopy

    International Nuclear Information System (INIS)

    Popp, P.; Baumbach, J.I.; Leonhardt, J.W.; Mothes, S.

    1988-01-01

    Electron capture detectors have a high sensitivity for substances with high thermal electron attachment cross sections. The electron attachment spectroscopy makes it possible to change the mean electron energy in such a way that the maximum for dissociative electron attachment is reached. Thus, best operation modes of the detection system as well as significant dependencies of electron attachment coefficients are available. Cross sections for electron attachment as a function of the electron energy are obtained with the knowledge of electron energy distribution functions from Boltzmann equation analysis by a special computer code. A disadvantage of this electron attachment spectroscopy is the superposition of space charge effects due to the decrease of the electron drift velocity with increasing mean electron energy. These influences are discussed. (author)

  16. Auroal electron distribution function

    International Nuclear Information System (INIS)

    Kaufmann, R.L.; Dusenbery, P.B.; Thomas, B.J.; Arnoldy, R.L.

    1978-01-01

    The electron velocity distribution function is presented in the energy range 25 eV 8 cm/s (E=300 eV) are nearly isotropic in pitch angle throughout the flight. Upgoing electrons show almost no pitch angle dependence beyond 120 0 , and their fluxes decline smoothly as energy increases, with little or no evidence of a plateau. Preliminary results of numerical integrations, to study bulk properties and stability of the plasma are presented

  17. Mathematics for electronic technology

    CERN Document Server

    Howson, D P

    1975-01-01

    Mathematics for Electronic Technology is a nine-chapter book that begins with the elucidation of the introductory concepts related to use of mathematics in electronic engineering, including differentiation, integration, partial differentiation, infinite series, vectors, vector algebra, and surface, volume and line integrals. Subsequent chapters explore the determinants, differential equations, matrix analysis, complex variable, topography, graph theory, and numerical analysis used in this field. The use of Fourier method for harmonic analysis and the Laplace transform is also described. The ma

  18. Electricity electron measurement

    International Nuclear Information System (INIS)

    Kim, Sang Jin; Sung, Rak Jin

    1985-11-01

    This book deals with measurement of electricity and electron. It is divided into fourteen chapters, which depicts basic of electricity measurement, unit and standard, important electron circuit for measurement, instrument of electricity, impedance measurement, power and power amount measurement, frequency and time measurement, waveform measurement, record instrument and direct viewing instrument, super high frequency measurement, digital measurement on analog-digital convert, magnetic measurement on classification by principle of measurement, measurement of electricity application with principle sensors and systematization of measurement.

  19. Electron affinities: theoretical

    International Nuclear Information System (INIS)

    Kaufman, J.J.

    1976-01-01

    A brief description is given of the conceptual background and formalism of the various ab-initio and semi-ab-initio quantum computational techniques for calculating atomic and molecular electron affinities: Hartree--Fock--Roothaan SCF, configuration interaction (CI), multiconfiguration SCF (MC-SCF), Bethe--Goldstone, superposition of configurations (SOC), ab-initio effective core model potentials, Xα-MS, plus other less common methods. Illustrative and comparative examples of electron affinities calculated by these various methods are presented

  20. Electronics practice technology

    International Nuclear Information System (INIS)

    1995-01-01

    This book concentrates on electronic technology. It deals with kinds of terminal and mounting such as teflon terminal, steatite terminal, and harmonica terminal, small parts like connector, plug jack, vernier dial, and coupling, termination of wiring, kinds of switch and mounting, a condenser, fixed resistor, trance coil, loading of semiconductor, mounting of high input impedance circuit, mounting of electric power circuit, manufacturing of print substrate and practice of manufacturing for print substrate. This is one of series books on electronic technology.

  1. Electron-ion collisions

    International Nuclear Information System (INIS)

    Crandall, D.H.

    1982-01-01

    This discussion concentrates on basic physics aspects of inelastic processes of excitation, ionization, and recombination that occur during electron-ion collisions. Except for cases of illustration along isoelectronic sequences, only multicharged (at least +2) ions will be specifically discussed with some emphasis of unique physics aspects associated with ionic charge. The material presented will be discussed from a primarily experimental viewpoint with most attention to electron-ion interacting beams experiments

  2. Newnes electronics toolkit

    CERN Document Server

    Phillips, Geoff

    2013-01-01

    Newnes Electronics Toolkit brings together fundamental facts, concepts, and applications of electronic components and circuits, and presents them in a clear, concise, and unambiguous format, to provide a reference book for engineers. The book contains 10 chapters that discuss the following concepts: resistors, capacitors, inductors, semiconductors, circuit concepts, electromagnetic compatibility, sound, light, heat, and connections. The engineer's job does not end when the circuit diagram is completed; the design for the manufacturing process is just as important if volume production is to be

  3. Electronic states of myricetin

    DEFF Research Database (Denmark)

    Vojta, Danijela; Karlsen, Eva; Spanget-Larsen, Jens

    2017-01-01

    Myricetin (3,3',4',5,5',7'-hexahydroxyflavone) was investigated by linear dichroism spectroscopy on molecular samples partially aligned in stretched poly(vinyl alcohol) (PVA). At least five electronic transitions in the range 40000 – 20000 cm–1 were characterized with respect to their wavenumbers......, relative intensities, and transition moment directions. The observed bands were assigned to electronic transitions predicted with TD-B3LYP/6-31+G(d,p)....

  4. Newnes electronics assembly handbook

    CERN Document Server

    Brindley, Keith

    2013-01-01

    Newnes Electronics Assembly Handbook: Techniques, Standards and Quality Assurance focuses on the aspects of electronic assembling. The handbook first looks at the printed circuit board (PCB). Base materials, basic mechanical properties, cleaning of assemblies, design, and PCB manufacturing processes are then explained. The text also discusses surface mounted assemblies and packaging of electromechanical assemblies, as well as the soldering process. Requirements for the soldering process; solderability and protective coatings; cleaning of PCBs; and mass solder/component reflow soldering are des

  5. The Recycler Electron Cooler

    Energy Technology Data Exchange (ETDEWEB)

    Shemyakin, A. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Prost, L. R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2013-03-19

    The Recycler Electron cooler was the first (and so far, the only) cooler working at a relativistic energy (γ = 9.5). It was successfully developed in 1995-2004 and was in operation at Fermilab in 2005-2011, providing cooling of antiprotons in the Recycler ring. This paper describes the cooler, difficulties in achieving the required electron beam parameters and the ways to overcome them, cooling measurements, and details of operation.

  6. Weakly oval electron lense

    International Nuclear Information System (INIS)

    Daumenov, T.D.; Alizarovskaya, I.M.; Khizirova, M.A.

    2001-01-01

    The method of the weakly oval electrical field getting generated by the axially-symmetrical field is shown. Such system may be designed with help of the cylindric form coaxial electrodes with the built-in quadrupole duplet. The singularity of the indicated weakly oval lense consists of that it provides the conducting both mechanical and electronic adjustment. Such lense can be useful for elimination of the near-axis astigmatism in the electron-optical system

  7. Electronics 3 checkbook

    CERN Document Server

    Knight, S A; May, A J C

    2013-01-01

    Electronics 3 Checkbook provides a concise coverage of the theories and definitions of concepts in electronics. The book provides problems and worked examples to supplement fuller textbooks of the same subject. The coverage of the text includes decibel measurement, operational amplifiers, DA and AD converters, controlled rectifiers, triggering devices, optoelectronic devices, fiber optics, and power amplifiers. The text will be of great use to electrical engineering students who wish to enhance their understanding of the basics of mechanical and electrical science.

  8. Antifragile Electronic Warfare

    OpenAIRE

    Lichtman, Marc

    2014-01-01

    This letter introduces the concept of antifragile electronic warfare (EW), which we define as the ability to allow a communications link to improve performance due to the presence of a jammer. This concept should not be confused with jamming countermeasures (a.k.a. anti-jamming or electronic protection). Rather, antifragile EW can be thought of as the next step beyond simply avoiding or mitigating jamming. After introducing the concept we narrow down the subset of jammers this concept can be ...

  9. Electrical and electronic principles

    CERN Document Server

    Knight, SA

    1988-01-01

    Electrical and Electronic Principles, 3 focuses on the principles involved in electrical and electronic circuits, including impedance, inductance, capacitance, and resistance.The book first deals with circuit elements and theorems, D.C. transients, and the series circuits of alternating current. Discussions focus on inductance and resistance in series, resistance and capacitance in series, power factor, impedance, circuit magnification, equation of charge, discharge of a capacitor, transfer of power, and decibels and attenuation. The manuscript then examines the parallel circuits of alternatin

  10. Nuclear electronics laboratory manual

    International Nuclear Information System (INIS)

    1984-05-01

    The Nuclear Electronics Laboratory Manual is a joint product of several electronics experts who have been associated with IAEA activity in this field for many years. The manual does not include experiments of a basic nature, such as characteristics of different active electronics components. It starts by introducing small electronics blocks, employing one or more active components. The most demanding exercises instruct a student in the design and construction of complete circuits, as used in commercial nuclear instruments. It is expected that a student who completes all the experiments in the manual should be in a position to design nuclear electronics units and also to understand the functions of advanced commercial instruments which need to be repaired or maintained. The future tasks of nuclear electronics engineers will be increasingly oriented towards designing and building the interfaces between a nuclear experiment and a computer. The manual pays tribute to this development by introducing a number of experiments which illustrate the principles and the technology of interfacing

  11. Auroral electron energies

    International Nuclear Information System (INIS)

    McEwan, D.J.; Duncan, C.N.; Montalbetti, R.

    1981-01-01

    Auroral electron characteristic energies determined from ground-based photometer measurements of the ratio of 5577 A OI and 4278 A N 2 + emissions are compared with electron energies measured during two rocket flights into pulsating aurora. Electron spectra with Maxwellian energy distributions were observed in both flights with an increase in characteristic energy during each pulsation. During the first flight on February 15, 1980 values of E 0 ranging from 1.4 keV at pulsation minima to 1.8 keV at pulsation maxima were inferred from the 5577/4278 ratios, in good agreement with rocket measurements. During the second flight on February 23, direct electron energy measurements yielded E 0 values of 1.8 keV rising to 2.1 keV at pulsation maxima. The photometric ratio measurements in this case gave inferred E 0 values about 0.5 keV lower. This apparent discrepancy is considered due to cloud cover which impaired the absolute emission intensity measurements. It is concluded that the 5577/4278 ratio does yield a meaningful measure of the characteristic energy of incoming electrons. This ratio technique, when added to the more sensitive 6300/4278 ratio technique usable in stable auroras can now provide more complete monitoring of electron influx characteristics. (auth)

  12. Netiquette in Electronic Communication

    Directory of Open Access Journals (Sweden)

    Tomáš Kozík

    2014-06-01

    Full Text Available Electronic mail and electronic communications systems are considered significant and effective tools of communication. One of the most widespread electronic communication tools is e - mail communication. In order to avoid misinterpretation of the report on the side of the recipient, it is need to pay attention to the writing of e - mail messages as well as to their content. With the continuous expansion of the use of electronic communication there have gradually developed certain rules of etiquette in electronic communications. The existing rules of the propriety ones are expressed in the term " etiqutte " and are not automatically applied in the new communications environment - media. For electronic communication, the new rules of etiquette have been stabilised into a term NETIQUETTE. The word netiquette was created by combining words NET (net and ETIKETA (a set of rules of social behavior and habits. Netiquette constitutes the rules of the behavior of users on a network. Although the netiquette is merely "an unwritten set of rules", their not using can be understood as a type of disrespect. Analysis of knowledge of domestic and foreign sources as well as results of a survey confirmed the justification of paying attention to the education of individuals in NETIQUETTE, irrespective of the degree of education.

  13. HDTV versus electronic cinema

    Science.gov (United States)

    Tinker, Michael

    1998-12-01

    We are on the brink of transforming the movie theatre with electronic cinema. Technologies are converging to make true electronic cinema, with a 'film look,' possible for the first time. In order to realize the possibilities, we must leverage current technologies in video compression, electronic projection, digital storage, and digital networks. All these technologies have only recently improved sufficiently to make their use in the electronic cinema worthwhile. Video compression, such as MPEG-2, is designed to overcome the limitations of video, primarily limited bandwidth. As a result, although HDTV offers a serious challenge to film-based cinema, it falls short in a number of areas, such as color depth. Freed from the constraints of video transmission, and using the recently improved technologies available, electronic cinema can move beyond video; Although movies will have to be compressed for some time, what is needed is a concept of 'cinema compression,' rather than video compression. Electronic cinema will open up vast new possibilities for viewing experiences at the theater, while at the same time offering up the potential for new economies in the movie industry.

  14. Transformational III-V Electronics

    KAUST Repository

    Nour, Maha A.

    2014-01-01

    Flexible electronics using III-V materials for nano-electronics with high electron mobility and optoelectronics with direct band gap are attractive for many applications. This thesis describes a complementary metal oxide semiconductor (CMOS

  15. Beginning analog electronics through projects

    CERN Document Server

    Singmin, Andrew

    2001-01-01

    Analog electronics is the simplest way to start a fun, informative, learning program. Beginning Analog Electronics Through Projects, Second Edition was written with the needs of beginning hobbyists and students in mind. This revision of Andrew Singmin's popular Beginning Electronics Through Projects provides practical exercises, building techniques, and ideas for useful electronics projects. Additionally, it features new material on analog and digital electronics, and new projects for troubleshooting test equipment.Published in the tradition of Beginning Electronics Through Projects an

  16. Electron Accumulative Molecules.

    Science.gov (United States)

    Buades, Ana B; Sanchez Arderiu, Víctor; Olid-Britos, David; Viñas, Clara; Sillanpää, Reijo; Haukka, Matti; Fontrodona, Xavier; Paradinas, Markos; Ocal, Carmen; Teixidor, Francesc

    2018-02-28

    With the goal to produce molecules with high electron accepting capacity and low reorganization energy upon gaining one or more electrons, a synthesis procedure leading to the formation of a B-N(aromatic) bond in a cluster has been developed. The research was focused on the development of a molecular structure able to accept and release a specific number of electrons without decomposing or change in its structural arrangement. The synthetic procedure consists of a parallel decomposition reaction to generate a reactive electrophile and a synthesis reaction to generate the B-N(aromatic) bond. This procedure has paved the way to produce the metallacarboranylviologen [M(C 2 B 9 H 11 )(C 2 B 9 H 10 )-NC 5 H 4 -C 5 H 4 N-M'(C 2 B 9 H 11 )(C 2 B 9 H 10 )] (M = M' = Co, Fe and M = Co and M' = Fe) and semi(metallacarboranyl)viologen [3,3'-M(8-(NC 5 H 4 -C 5 H 4 N-1,2-C 2 B 9 H 10 )(1',2'-C 2 B 9 H 11 )] (M = Co, Fe) electron cumulative molecules. These molecules are able to accept up to five electrons and to donate one in single electron steps at accessible potentials and in a reversible way. By targeted synthesis and corresponding electrochemical tests each electron transfer (ET) step has been assigned to specific fragments of the molecules. The molecules have been carefully characterized, and the electronic communication between both metal centers (when this situation applies) has been definitely observed through the coplanarity of both pyridine fragments. The structural characteristics of these molecules imply a low reorganization energy that is a necessary requirement for low energy ET processes. This makes them electronically comparable to fullerenes, but on their side, they have a wide range of possible solvents. The ET from one molecule to another has been clearly demonstrated as well as their self-organizing capacity. We consider that these molecules, thanks to their easy synthesis, ET, self-organizing capacity, wide range of solubility, and easy processability, can

  17. Electronic Submissions of Pesticide Applications

    Science.gov (United States)

    Applications for pesticide registration can be submitted electronically, including forms, studies, and draft product labeling. Applicants need not submit multiple electronic copies of any pieces of their applications.

  18. Electron beams and applications

    International Nuclear Information System (INIS)

    Haouat, G.; Couillaud, C.

    1998-01-01

    Studies of the physical properties of the ELSA-linac electron beam are presented. They include measurements of the characteristic beam parameter and analyzes of the beam transport using simulation codes. The aim of these studies is to determine the best conditions for production of intense and very short electron bunches and to optimize the transport of space-charge dominated beams. Precise knowledge of the transport dynamics allows to produce beams with the required characteristics for light production in Free-Electron Laser (FEL), and to give a good description of energy-transfer phenomena between electrons and photons in the wriggler. The particular features of ELSA authorize studies of high-intensity, high-brightness beam properties, especially the halo surrounding the dense core of the electron bunches, which is formed by the space charge effects. It is also shown that the ELSA facility is well suited for the fabrication of very short γ and X-rays sources for applied research in nuclear and plasma physics, or for time response studies of fast detectors. (author)

  19. Auroral electron time dispersion

    International Nuclear Information System (INIS)

    Kletzing, C.A.

    1989-01-01

    A sounding rocket flight was launched from Greenland in 1985 to study high latitude, early morning auroral physics. The payload was instrumented with electron and ion detectors, AC and DC electric field experiments, a plasma density experiment, and a magnetometer to measure the ambient field. The rocket was launched during disturbed conditions, when the polar cap was in a contracted state with visible aurora overhead. The electron data contained numerous signatures indicative of time-of-flight energy dispersion characterized by a coherent structure in which lower energy electrons arrived at the rocket after higher energy electrons. A model was constructed to explain this phenomena by the sudden application of a region of parallel electric field along a length of magnetic field line above the rocket. The model incorporates detector response and uses an altitudinal density profile based on auroral zone measurements. Three types of potential structures were tried: linear, quadratic and cubic. Of the three it was found that the cubic (electric field growing in a quadratic manner moving up the field line) produced the best fit to the data. The potential region was found to be approximately 1-2 R e in extent with the lower edge 3000-4000 km away from the rocket. The background electron temperature in the model which produced the best fit to the data was of the order of 15 eV

  20. Electron irradiation of zeolites

    International Nuclear Information System (INIS)

    Wang, S.X.; Wang, L.M.; Ewing, R.C.

    1999-01-01

    Three different zeolites (analcime, natrolite, and zeolite-Y) were irradiated with 200 keV and 400 keV electrons. All zeolites amorphized under a relatively low electron fluence. The transformation from the crystalline-to-amorphous state was continuous and homogeneous. The electron fluences for amorphization of the three zeolites at room temperature were: 7.0 x 10 19 e - /cm 2 (analcime), 1.8 x 10 20 e - /cm 2 (natrolite), and 3.4 x 10 20 e - /cm 2 (zeolite-Y). The different susceptibilities to amorphization are attributed to the different channel sizes in the structures which are the pathways for the release of water molecules and Na + . Natrolite formed bubbles under electron irradiation, even before complete amorphization. Analcime formed bubbles after amorphization. Zeolite-Y did not form bubbles under irradiation. The differences in bubble formation are attributed to the different channel sizes of the three zeolites. The amorphization dose was also measured at different temperatures. An inverse temperature dependence of amorphization dose was observed for all three zeolites: electron dose for amorphization decreased with increasing temperature. This unique temperature effect is attributed to the fact that zeolites are thermally unstable. A semi-empirical model was derived to describe the temperature effect of amorphization in these zeolites

  1. Politics Under Electronic Simultaneity

    Directory of Open Access Journals (Sweden)

    Valery P. Terin

    2014-01-01

    Full Text Available In contradistinction to the book and the other typographic products, the electronic media operates on a 24-hour-a-day basis evoking simultaneity as the guiding mode of perception and thinking for all those under its influence. The discovery of this fact manifested itself in the formation and development of the managerial technologies operating by means of the electronic information environment and following the principle of simultaneity in the first place. Thus, at the end of the 1960s already the election campaigns in the U.S.A. began to operate on the basis of the final cause as the guiding principle of the country's mass consciousness motivating to carry out each particular event as if already rejoicing at the victory. With this in mind, there emerged a problem of applying this approach with its enormous managerial potential elsewhere. To add, simultaneity as a norm of perception and thinking turned out to be increasingly important with the advent of the electrical telegraph and the press relying on its short disconnected messages instantaneously arriving from all parts of the world. All the other media, which emerged in the wake of this development, has served to fortify this mode of thought as governing in the electronic information environment. The potential of the electronically operating global managerial technologies is quickly growing. The article also deals with the information overload and pattern recognition problem understood in managerial terms as well as mythologization and demythologization processes as they are necessitated by the electronic media coverage worldwide.

  2. Reversibly Bistable Flexible Electronics

    KAUST Repository

    Alfaraj, Nasir

    2015-05-01

    Introducing the notion of transformational silicon electronics has paved the way for integrating various applications with silicon-based, modern, high-performance electronic circuits that are mechanically flexible and optically semitransparent. While maintaining large-scale production and prototyping rapidity, this flexible and translucent scheme demonstrates the potential to transform conventionally stiff electronic devices into thin and foldable ones without compromising long-term performance and reliability. In this work, we report on the fabrication and characterization of reversibly bistable flexible electronic switches that utilize flexible n-channel metal-oxide-semiconductor field-effect transistors. The transistors are fabricated initially on rigid (100) silicon substrates before they are peeled off. They can be used to control flexible batches of light-emitting diodes, demonstrating both the relative ease of scaling at minimum cost and maximum reliability and the feasibility of integration. The peeled-off silicon fabric is about 25 µm thick. The fabricated devices are transferred to a reversibly bistable flexible platform through which, for example, a flexible smartphone can be wrapped around a user’s wrist and can also be set back to its original mechanical position. Buckling and cyclic bending of such host platforms brings a completely new dimension to the development of flexible electronics, especially rollable displays.

  3. Theory of runaway electrons

    Energy Technology Data Exchange (ETDEWEB)

    Dreicer, H [Los Alamos Scientific Laboratory, University of California, Los Alamos, NM (United States)

    1958-07-01

    This paper treats the problem of electrons moving through an infinite gas of positive ions under the influence of a static uniform electric field of arbitrary strength. In evaluating the electrical conductivity of such a gas the conventional treatment involves a perturbation solution of the time-independent Boltzmann equation, and results in the well-known (temperature){sup 3/2} law. Two assumptions are basic to these treatments: 1) that a steady state electron velocity distribution is attained several mean-free collision times after the electric field is applied, and 2) that the terminal electron drift velocity is small compared to the average random electron speed. Both assumptions are avoided in this paper. In the next section the problem is formulated starting with the Boltzmann equation and a review of approximate analytic solutions appropriate to the weak and strong electric field cases is presented. We then describe a time-dependent numerical solution to the Boltzmann equation and compare these results with the approximate solutions. All of these treatments lead to the conclusion that this problem does not admit a time-independent solution. Because of the strong energy dependence of the Rutherford scattering law, the electron drift velocity is not bounded by a terminal value, rather it grows monotonically with time. This is the so-called runaway effect predicted by Giovanelli. Collective effects, or plasma oscillations, are ignored in this work, although these undoubtedly play an important role in the conduction of electricity through the plasma.

  4. Microfluidic stretchable RF electronics.

    Science.gov (United States)

    Cheng, Shi; Wu, Zhigang

    2010-12-07

    Stretchable electronics is a revolutionary technology that will potentially create a world of radically different electronic devices and systems that open up an entirely new spectrum of possibilities. This article proposes a microfluidic based solution for stretchable radio frequency (RF) electronics, using hybrid integration of active circuits assembled on flex foils and liquid alloy passive structures embedded in elastic substrates, e.g. polydimethylsiloxane (PDMS). This concept was employed to implement a 900 MHz stretchable RF radiation sensor, consisting of a large area elastic antenna and a cluster of conventional rigid components for RF power detection. The integrated radiation sensor except the power supply was fully embedded in a thin elastomeric substrate. Good electrical performance of the standalone stretchable antenna as well as the RF power detection sub-module was verified by experiments. The sensor successfully detected the RF radiation over 5 m distance in the system demonstration. Experiments on two-dimensional (2D) stretching up to 15%, folding and twisting of the demonstrated sensor were also carried out. Despite the integrated device was severely deformed, no failure in RF radiation sensing was observed in the tests. This technique illuminates a promising route of realizing stretchable and foldable large area integrated RF electronics that are of great interest to a variety of applications like wearable computing, health monitoring, medical diagnostics, and curvilinear electronics.

  5. Electron guns for accelerators

    International Nuclear Information System (INIS)

    Rangarajan, L.M.; Mahadevan, S.; Ramamurthi, S.S.

    1995-01-01

    The high voltage, high current electron guns developed elsewhere for Linacs are based on cathode pulsing with direct emitting cathodes. Our grid pulsed triode gun employs indirect emitting cathode pellet under electron bombardment or a direct cathode emitter. Electron beam from the gun is injected to the accelerator guide at 40 kV and pulse duration is 2.8μsec. The gun is limited to axially symmetric geometry and electron optical design is optimized by computer programming. The gun with a water cooled Faraday cup is connected to a vacuum system comprising of a sputter ion pump and sorption pump. Working pressure is 1x10 -6 Pa. Gun is designed to be baked as an assembly at temperatures of 400 degC while vacuum processing. Materials are therefore restricted to refractory metals, SS, OFHC copper and all the electrodes are housed inside a ceramic tube. Lower Z graphite is used as a base material of Faraday cup. Grid is non-intercepting modulator anode, a new feature introduced, as compared to meshed grid system by others. CAT gun delivers 160 mA current pulses at 40 kV and its working characteristics such as perveance, emittance and beam radius compare well with SLAC and Hermosa guns. The above guns can be used for electron beam machines such as medical Linacs, industrial accelerators and EB welding equipment. (author). 2 refs., 2 figs

  6. Electron microscope phase enhancement

    Science.gov (United States)

    Jin, Jian; Glaeser, Robert M.

    2010-06-15

    A microfabricated electron phase shift element is used for modifying the phase characteristics of an electron beam passing though its center aperture, while not affecting the more divergent portion of an incident beam to selectively provide a ninety-degree phase shift to the unscattered beam in the back focal plan of the objective lens, in order to realize Zernike-type, in-focus phase contrast in an electron microscope. One application of the element is to increase the contrast of an electron microscope for viewing weakly scattering samples while in focus. Typical weakly scattering samples include biological samples such as macromolecules, or perhaps cells. Preliminary experimental images demonstrate that these devices do apply a ninety degree phase shift as expected. Electrostatic calculations have been used to determine that fringing fields in the region of the scattered electron beams will cause a negligible phase shift as long as the ratio of electrode length to the transverse feature-size aperture is about 5:1. Calculations are underway to determine the feasibility of aspect smaller aspect ratios of about 3:1 and about 2:1.

  7. Electron-molecule collisions

    International Nuclear Information System (INIS)

    Shimamura, I.; Takayanagi, K.

    1984-01-01

    The study of collision processes plays an important research role in modern physics. Many significant discoveries have been made by means of collision experiments. Based on theoretical, experimental, and computational studies, this volume presents an overview detailing the basic processes of electron-molecule collisions. The editors have collected papers-written by a group of international experts-that consider a diverse range of phenomena occurring in electronmolecule collisions. The volume discusses first the basic formulation for scattering problems and then gives an outline of the physics of electron-molecule collisions. The main topics covered are rotational transitions, vibrational transitions, dissociation of molecules in slow collisions, the electron-molecule collision as a spectroscopic tool for studying molecular electronic structures, and experimental and computational techniques for determining the cross sections. These well-referenced chapters are self-contained and can be read independently or consecutively. Authoritative and up-to-date, Electron-Molecule Collisions is a useful addition to the libraries of students and researchers in the fields of atomic, molecular, and chemical physics, and physical chemistry

  8. Electronic Commerce user manual

    Energy Technology Data Exchange (ETDEWEB)

    1992-04-10

    This User Manual supports the Electronic Commerce Standard System. The Electronic Commerce Standard System is being developed for the Department of Defense of the Technology Information Systems Program at the Lawrence Livermore National Laboratory, operated by the University of California for the Department of Energy. The Electronic Commerce Standard System, or EC as it is known, provides the capability for organizations to conduct business electronically instead of through paper transactions. Electronic Commerce and Computer Aided Acquisition and Logistics Support, are two major projects under the DoD`s Corporate Information Management program, whose objective is to make DoD business transactions faster and less costly by using computer networks instead of paper forms and postage. EC runs on computers that use the UNIX operating system and provides a standard set of applications and tools that are bound together by a common command and menu system. These applications and tools may vary according to the requirements of the customer or location and may be customized to meet the specific needs of an organization. Local applications can be integrated into the menu system under the Special Databases & Applications option on the EC main menu. These local applications will be documented in the appendices of this manual. This integration capability provides users with a common environment of standard and customized applications.

  9. Electronic Commerce user manual

    Energy Technology Data Exchange (ETDEWEB)

    1992-04-10

    This User Manual supports the Electronic Commerce Standard System. The Electronic Commerce Standard System is being developed for the Department of Defense of the Technology Information Systems Program at the Lawrence Livermore National Laboratory, operated by the University of California for the Department of Energy. The Electronic Commerce Standard System, or EC as it is known, provides the capability for organizations to conduct business electronically instead of through paper transactions. Electronic Commerce and Computer Aided Acquisition and Logistics Support, are two major projects under the DoD's Corporate Information Management program, whose objective is to make DoD business transactions faster and less costly by using computer networks instead of paper forms and postage. EC runs on computers that use the UNIX operating system and provides a standard set of applications and tools that are bound together by a common command and menu system. These applications and tools may vary according to the requirements of the customer or location and may be customized to meet the specific needs of an organization. Local applications can be integrated into the menu system under the Special Databases Applications option on the EC main menu. These local applications will be documented in the appendices of this manual. This integration capability provides users with a common environment of standard and customized applications.

  10. Electronic Materials Science

    Science.gov (United States)

    Irene, Eugene A.

    2005-02-01

    A thorough introduction to fundamental principles and applications From its beginnings in metallurgy and ceramics, materials science now encompasses such high- tech fields as microelectronics, polymers, biomaterials, and nanotechnology. Electronic Materials Science presents the fundamentals of the subject in a detailed fashion for a multidisciplinary audience. Offering a higher-level treatment than an undergraduate textbook provides, this text benefits students and practitioners not only in electronics and optical materials science, but also in additional cutting-edge fields like polymers and biomaterials. Readers with a basic understanding of physical chemistry or physics will appreciate the text's sophisticated presentation of today's materials science. Instructive derivations of important formulae, usually omitted in an introductory text, are included here. This feature offers a useful glimpse into the foundations of how the discipline understands such topics as defects, phase equilibria, and mechanical properties. Additionally, concepts such as reciprocal space, electron energy band theory, and thermodynamics enter the discussion earlier and in a more robust fashion than in other texts. Electronic Materials Science also features: An orientation towards industry and academia drawn from the author's experience in both arenas Information on applications in semiconductors, optoelectronics, photocells, and nanoelectronics Problem sets and important references throughout Flexibility for various pedagogical needs Treating the subject with more depth than any other introductory text, Electronic Materials Science prepares graduate and upper-level undergraduate students for advanced topics in the discipline and gives scientists in associated disciplines a clear review of the field and its leading technologies.

  11. Need for accelerating electrons

    International Nuclear Information System (INIS)

    Kerst, D.W.

    1987-01-01

    Photons for nuclear disintegration experiments were not abundantly available in the early days of nuclear physics, whereas accelerated ions led the way. When electrons could be accelerated into the 20--30 MeV range, they found application not only to nuclear disintegration of the elements of the periodic table but also to x-ray radiography and to deep therapy. Energies of interest for probing nuclear structure by electron scattering and for meson production followed soon after. The elementary nature of the electron has now made it a valuable tool for present day particle physics; and the synchrotron radiation, which is an obstacle for some accelerating processes, has become a much sought after source of photons for experiments at atomic structure energies

  12. Electronic structure of silicene

    International Nuclear Information System (INIS)

    Voon, L. C. Lew Yan

    2015-01-01

    In this topical review, we discuss the electronic structure of free-standing silicene by comparing results obtained using different theoretical methods. Silicene is a single atomic layer of silicon similar to graphene. The interest in silicene is the same as for graphene, in being two-dimensional and possessing a Dirac cone. One advantage of silicene is due to its compatibility with current silicon electronics. Both empirical and first-principles techniques have been used to study the electronic properties of silicene. We will provide a brief overview of the parameter space for first-principles calculations. However, since the theory is standard, no extensive discussion will be included. Instead, we will emphasize what empirical methods can provide to such investigations and the current state of these theories. Finally, we will review the properties computed using both types of theories for free-standing silicene, with emphasis on areas where we have contributed. Comparisons to graphene is provided throughout. (topical review)

  13. Electron microscopy in metallurgy

    International Nuclear Information System (INIS)

    Loretto, M.H.

    1980-01-01

    The aim of this paper is to review briefly the contribution which (TEM) transmission electron microscopy (including high voltage electron microscopy (HVEM)) has made to metallurgy. Since it is straightforward with modern electron microscopes to extract the crystallographic information which provides the basis for any interpretation, the major problem in most metallurgical work lies in assessing how the structure (which TEM has characterised) has arisen and which properties of the specimen can be understood in terms of this structure. Radiation damage, quenching, phase transformations, grain boundaries and plastic deformation have been the main fields in which TEM has contributed significantly. After briefly summarising the role of TEM in each field, examples of recent work will be used to indicate current TEM activity in physical metallurgy. (author)

  14. Wireless Biological Electronic Sensors.

    Science.gov (United States)

    Cui, Yue

    2017-10-09

    The development of wireless biological electronic sensors could open up significant advances for both fundamental studies and practical applications in a variety of areas, including medical diagnosis, environmental monitoring, and defense applications. One of the major challenges in the development of wireless bioelectronic sensors is the successful integration of biosensing units and wireless signal transducers. In recent years, there are a few types of wireless communication systems that have been integrated with biosensing systems to construct wireless bioelectronic sensors. To successfully construct wireless biological electronic sensors, there are several interesting questions: What types of biosensing transducers can be used in wireless bioelectronic sensors? What types of wireless systems can be integrated with biosensing transducers to construct wireless bioelectronic sensors? How are the electrical sensing signals generated and transmitted? This review will highlight the early attempts to address these questions in the development of wireless biological electronic sensors.

  15. Beam electron microprobe

    CERN Document Server

    Stoller, D; Muterspaugh, M W; Pollock, R E

    1999-01-01

    A beam profile monitor based on the deflection of a probe electron beam by the electric field of a stored, electron-cooled proton beam is described and first results are presented. Electrons were transported parallel to the proton beam by a uniform longitudinal magnetic field. The probe beam may be slowly scanned across the stored beam to determine its intensity, position, and size. Alternatively, it may be scanned rapidly over a narrow range within the interior of the stored beam for continuous observation of the changing central density during cooling. Examples of a two dimensional charge density profile obtained from a raster scan and of a cooling alignment study illustrate the scope of measurements made possible by this device.

  16. Noncovalent Molecular Electronics.

    Science.gov (United States)

    Gryn'ova, G; Corminboeuf, C

    2018-05-03

    Molecular electronics covers several distinctly different conducting architectures, including organic semiconductors and single-molecule junctions. The noncovalent interactions, abundant in the former, are also often found in the latter, i.e., the dimer junctions. In the present work, we draw the parallel between the two types of noncovalent molecular electronics for a range of π-conjugated heteroaromatic molecules. In silico modeling allows us to distill the factors that arise from the chemical nature of their building blocks and from their mutual arrangement. We find that the same compounds are consistently the worst and the best performers in the two types of electronic assemblies, emphasizing the universal imprint of the underlying chemistry of the molecular cores on their diverse charge transport characteristics. The interplay between molecular and intermolecular factors creates a spectrum of noncovalent conductive architectures, which can be manipulated using the design strategies based upon the established relationships between chemistry and transport.

  17. PHERMEX electron gun development

    International Nuclear Information System (INIS)

    Builta, L.A.; Elliott, J.C.; Moir, D.C.; Starke, T.P.; Vecere, C.A.

    1983-01-01

    The PHERMEX facility is a 50-MHz standing-wave linear accelerator. Electrons are injected, accelerated, and transported to a tungsten target where bremsstrahlung x rays are generated for flash radiography of hydrodynamic systems. The purpose of this article is to describe the progress of PHERMEX electron gun development. The goal of this program is to generate and transport a 200-ns, 1-MV, 1-kA electron beam into the first PHERMEX accelerating cavity. The standard gun is operated at a pulse voltage of 550 kV, which is the limit determined by internal breakdown of the vacuum insulator. This insulator has been redesigned, and the gun has been pulsed at 750 kV without internal breakdown. At present, the current output is not limited by voltage but by a phenomenon called pulse shortening, which occurs at a pulse voltage of approximately 650 kV. The phenomenon has been investigated and the results are presented

  18. Phasor power electronics

    CERN Document Server

    Rim, Chun T

    2016-01-01

    This book presents a comprehensive introduction to the principles of power electronics, focusing on the switched transformer concept and phasor transformation techniques as employed in the analysis and design of power electronic circuits. Phasor transformations, as introduced in this book, make the time-varying nature of a switching converter simple and easy to handle, transforming it into an equivalent time-invariant circuit. The book starts with an introduction to the philosophy and fundamental principles of power electronics. The switched transformer concept, which is applicable to any switching converter, is introduced, and it is shown how DC-DC converters analyses are then so straightforward that very little equational manipulation is needed. Then the phasor transformation techniques are comprehensively explained over three parts. Single phase and multi-phase AC systems are dealt with through the single phase phasor transformation and circuit DQ transformation, respectively. A general unified phasor tran...

  19. Polarized electron sources

    International Nuclear Information System (INIS)

    Clendenin, J.E.

    1995-05-01

    Polarized electron sources for high energy accelerators took a significant step forward with the introduction of a new laser-driven photocathode source for the SLC in 1992. With an electron beam polarization of >80% and with ∼99% uptime during continuous operation, this source is a key factor in the success of the current SLC high-energy physics program. The SLC source performance is used to illustrate both the capabilities and the limitations of solid-state sources. The beam requirements for future colliders are similar to that of the SLC with the addition in most cases of multiple-bunch operation. A design for the next generation accelerator source that can improve the operational characteristics and at least minimize some of the inherent limitations of present sources is presented. Finally, the possibilities for producing highly polarized electron beams for high-duty-factor accelerators are discussed

  20. Plasma relativistic microwave electronics

    International Nuclear Information System (INIS)

    Kuzelev, M.V.; Loza, O.T.; Rukhadze, A.A.; Strelkov, P.S.; Shkvarunets, A.G.

    2001-01-01

    One formulated the principles of plasma relativistic microwave electronics based on the induced Cherenkov radiation of electromagnetic waves at interaction of a relativistic electron beam with plasma. One developed the theory of plasma relativistic generators and accelerators of microwave radiation, designed and studied the prototypes of such devices. One studied theoretically the mechanisms of radiation, calculated the efficiencies and the frequency spectra of plasma relativistic microwave generators and accelerators. The theory findings are proved by the experiment: intensity of the designed sources of microwave radiation is equal to 500 μW, the frequency of microwave radiation is increased by 7 times (from 4 up to 28 GHz), the width of radiation frequency band may vary from several up to 100%. The designed sources of microwave radiation are no else compared in the electronics [ru